diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/Makefile | 11 | ||||
| -rw-r--r-- | drivers/char/n_gsm.c | 2763 | ||||
| -rw-r--r-- | drivers/char/n_hdlc.c | 1007 | ||||
| -rw-r--r-- | drivers/char/n_r3964.c | 1264 | ||||
| -rw-r--r-- | drivers/char/n_tty.c | 2121 | ||||
| -rw-r--r-- | drivers/char/pty.c | 777 | ||||
| -rw-r--r-- | drivers/char/sysrq.c | 811 | ||||
| -rw-r--r-- | drivers/char/tty_audit.c | 358 | ||||
| -rw-r--r-- | drivers/char/tty_buffer.c | 524 | ||||
| -rw-r--r-- | drivers/char/tty_io.c | 3263 | ||||
| -rw-r--r-- | drivers/char/tty_ioctl.c | 1179 | ||||
| -rw-r--r-- | drivers/char/tty_ldisc.c | 915 | ||||
| -rw-r--r-- | drivers/char/tty_mutex.c | 47 | ||||
| -rw-r--r-- | drivers/char/tty_port.c | 446 |
14 files changed, 1 insertions, 15485 deletions
diff --git a/drivers/char/Makefile b/drivers/char/Makefile index 3a9c014..f308494 100644 --- a/drivers/char/Makefile +++ b/drivers/char/Makefile @@ -7,19 +7,13 @@ # FONTMAPFILE = cp437.uni -obj-y += mem.o random.o tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o tty_buffer.o tty_port.o - -obj-y += tty_mutex.o -obj-$(CONFIG_LEGACY_PTYS) += pty.o -obj-$(CONFIG_UNIX98_PTYS) += pty.o +obj-y += mem.o random.o obj-$(CONFIG_TTY_PRINTK) += ttyprintk.o obj-y += misc.o obj-$(CONFIG_VT) += vt_ioctl.o vc_screen.o selection.o keyboard.o obj-$(CONFIG_BFIN_JTAG_COMM) += bfin_jtag_comm.o obj-$(CONFIG_CONSOLE_TRANSLATIONS) += consolemap.o consolemap_deftbl.o obj-$(CONFIG_HW_CONSOLE) += vt.o defkeymap.o -obj-$(CONFIG_AUDIT) += tty_audit.o -obj-$(CONFIG_MAGIC_SYSRQ) += sysrq.o obj-$(CONFIG_MVME147_SCC) += generic_serial.o vme_scc.o obj-$(CONFIG_MVME162_SCC) += generic_serial.o vme_scc.o obj-$(CONFIG_BVME6000_SCC) += generic_serial.o vme_scc.o @@ -41,8 +35,6 @@ obj-$(CONFIG_ISI) += isicom.o obj-$(CONFIG_SYNCLINK) += synclink.o obj-$(CONFIG_SYNCLINKMP) += synclinkmp.o obj-$(CONFIG_SYNCLINK_GT) += synclink_gt.o -obj-$(CONFIG_N_HDLC) += n_hdlc.o -obj-$(CONFIG_N_GSM) += n_gsm.o obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o obj-$(CONFIG_SX) += sx.o generic_serial.o obj-$(CONFIG_RIO) += rio/ generic_serial.o @@ -74,7 +66,6 @@ obj-$(CONFIG_PRINTER) += lp.o obj-$(CONFIG_APM_EMULATION) += apm-emulation.o obj-$(CONFIG_DTLK) += dtlk.o -obj-$(CONFIG_R3964) += n_r3964.o obj-$(CONFIG_APPLICOM) += applicom.o obj-$(CONFIG_SONYPI) += sonypi.o obj-$(CONFIG_RTC) += rtc.o diff --git a/drivers/char/n_gsm.c b/drivers/char/n_gsm.c deleted file mode 100644 index 04ef3ef..0000000 --- a/drivers/char/n_gsm.c +++ /dev/null @@ -1,2763 +0,0 @@ -/* - * n_gsm.c GSM 0710 tty multiplexor - * Copyright (c) 2009/10 Intel Corporation - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - * - * * THIS IS A DEVELOPMENT SNAPSHOT IT IS NOT A FINAL RELEASE * - * - * TO DO: - * Mostly done: ioctls for setting modes/timing - * Partly done: hooks so you can pull off frames to non tty devs - * Restart DLCI 0 when it closes ? - * Test basic encoding - * Improve the tx engine - * Resolve tx side locking by adding a queue_head and routing - * all control traffic via it - * General tidy/document - * Review the locking/move to refcounts more (mux now moved to an - * alloc/free model ready) - * Use newest tty open/close port helpers and install hooks - * What to do about power functions ? - * Termios setting and negotiation - * Do we need a 'which mux are you' ioctl to correlate mux and tty sets - * - */ - -#include <linux/types.h> -#include <linux/major.h> -#include <linux/errno.h> -#include <linux/signal.h> -#include <linux/fcntl.h> -#include <linux/sched.h> -#include <linux/interrupt.h> -#include <linux/tty.h> -#include <linux/ctype.h> -#include <linux/mm.h> -#include <linux/string.h> -#include <linux/slab.h> -#include <linux/poll.h> -#include <linux/bitops.h> -#include <linux/file.h> -#include <linux/uaccess.h> -#include <linux/module.h> -#include <linux/timer.h> -#include <linux/tty_flip.h> -#include <linux/tty_driver.h> -#include <linux/serial.h> -#include <linux/kfifo.h> -#include <linux/skbuff.h> -#include <linux/gsmmux.h> - -static int debug; -module_param(debug, int, 0600); - -#define T1 (HZ/10) -#define T2 (HZ/3) -#define N2 3 - -/* Use long timers for testing at low speed with debug on */ -#ifdef DEBUG_TIMING -#define T1 HZ -#define T2 (2 * HZ) -#endif - -/* Semi-arbitary buffer size limits. 0710 is normally run with 32-64 byte - limits so this is plenty */ -#define MAX_MRU 512 -#define MAX_MTU 512 - -/* - * Each block of data we have queued to go out is in the form of - * a gsm_msg which holds everything we need in a link layer independant - * format - */ - -struct gsm_msg { - struct gsm_msg *next; - u8 addr; /* DLCI address + flags */ - u8 ctrl; /* Control byte + flags */ - unsigned int len; /* Length of data block (can be zero) */ - unsigned char *data; /* Points into buffer but not at the start */ - unsigned char buffer[0]; -}; - -/* - * Each active data link has a gsm_dlci structure associated which ties - * the link layer to an optional tty (if the tty side is open). To avoid - * complexity right now these are only ever freed up when the mux is - * shut down. - * - * At the moment we don't free DLCI objects until the mux is torn down - * this avoid object life time issues but might be worth review later. - */ - -struct gsm_dlci { - struct gsm_mux *gsm; - int addr; - int state; -#define DLCI_CLOSED 0 -#define DLCI_OPENING 1 /* Sending SABM not seen UA */ -#define DLCI_OPEN 2 /* SABM/UA complete */ -#define DLCI_CLOSING 3 /* Sending DISC not seen UA/DM */ - - /* Link layer */ - spinlock_t lock; /* Protects the internal state */ - struct timer_list t1; /* Retransmit timer for SABM and UA */ - int retries; - /* Uplink tty if active */ - struct tty_port port; /* The tty bound to this DLCI if there is one */ - struct kfifo *fifo; /* Queue fifo for the DLCI */ - struct kfifo _fifo; /* For new fifo API porting only */ - int adaption; /* Adaption layer in use */ - u32 modem_rx; /* Our incoming virtual modem lines */ - u32 modem_tx; /* Our outgoing modem lines */ - int dead; /* Refuse re-open */ - /* Flow control */ - int throttled; /* Private copy of throttle state */ - int constipated; /* Throttle status for outgoing */ - /* Packetised I/O */ - struct sk_buff *skb; /* Frame being sent */ - struct sk_buff_head skb_list; /* Queued frames */ - /* Data handling callback */ - void (*data)(struct gsm_dlci *dlci, u8 *data, int len); -}; - -/* DLCI 0, 62/63 are special or reseved see gsmtty_open */ - -#define NUM_DLCI 64 - -/* - * DLCI 0 is used to pass control blocks out of band of the data - * flow (and with a higher link priority). One command can be outstanding - * at a time and we use this structure to manage them. They are created - * and destroyed by the user context, and updated by the receive paths - * and timers - */ - -struct gsm_control { - u8 cmd; /* Command we are issuing */ - u8 *data; /* Data for the command in case we retransmit */ - int len; /* Length of block for retransmission */ - int done; /* Done flag */ - int error; /* Error if any */ -}; - -/* - * Each GSM mux we have is represented by this structure. If we are - * operating as an ldisc then we use this structure as our ldisc - * state. We need to sort out lifetimes and locking with respect - * to the gsm mux array. For now we don't free DLCI objects that - * have been instantiated until the mux itself is terminated. - * - * To consider further: tty open versus mux shutdown. - */ - -struct gsm_mux { - struct tty_struct *tty; /* The tty our ldisc is bound to */ - spinlock_t lock; - - /* Events on the GSM channel */ - wait_queue_head_t event; - - /* Bits for GSM mode decoding */ - - /* Framing Layer */ - unsigned char *buf; - int state; -#define GSM_SEARCH 0 -#define GSM_START 1 -#define GSM_ADDRESS 2 -#define GSM_CONTROL 3 -#define GSM_LEN 4 -#define GSM_DATA 5 -#define GSM_FCS 6 -#define GSM_OVERRUN 7 - unsigned int len; - unsigned int address; - unsigned int count; - int escape; - int encoding; - u8 control; - u8 fcs; - u8 *txframe; /* TX framing buffer */ - - /* Methods for the receiver side */ - void (*receive)(struct gsm_mux *gsm, u8 ch); - void (*error)(struct gsm_mux *gsm, u8 ch, u8 flag); - /* And transmit side */ - int (*output)(struct gsm_mux *mux, u8 *data, int len); - - /* Link Layer */ - unsigned int mru; - unsigned int mtu; - int initiator; /* Did we initiate connection */ - int dead; /* Has the mux been shut down */ - struct gsm_dlci *dlci[NUM_DLCI]; - int constipated; /* Asked by remote to shut up */ - - spinlock_t tx_lock; - unsigned int tx_bytes; /* TX data outstanding */ -#define TX_THRESH_HI 8192 -#define TX_THRESH_LO 2048 - struct gsm_msg *tx_head; /* Pending data packets */ - struct gsm_msg *tx_tail; - - /* Control messages */ - struct timer_list t2_timer; /* Retransmit timer for commands */ - int cretries; /* Command retry counter */ - struct gsm_control *pending_cmd;/* Our current pending command */ - spinlock_t control_lock; /* Protects the pending command */ - - /* Configuration */ - int adaption; /* 1 or 2 supported */ - u8 ftype; /* UI or UIH */ - int t1, t2; /* Timers in 1/100th of a sec */ - int n2; /* Retry count */ - - /* Statistics (not currently exposed) */ - unsigned long bad_fcs; - unsigned long malformed; - unsigned long io_error; - unsigned long bad_size; - unsigned long unsupported; -}; - - -/* - * Mux objects - needed so that we can translate a tty index into the - * relevant mux and DLCI. - */ - -#define MAX_MUX 4 /* 256 minors */ -static struct gsm_mux *gsm_mux[MAX_MUX]; /* GSM muxes */ -static spinlock_t gsm_mux_lock; - -/* - * This section of the driver logic implements the GSM encodings - * both the basic and the 'advanced'. Reliable transport is not - * supported. - */ - -#define CR 0x02 -#define EA 0x01 -#define PF 0x10 - -/* I is special: the rest are ..*/ -#define RR 0x01 -#define UI 0x03 -#define RNR 0x05 -#define REJ 0x09 -#define DM 0x0F -#define SABM 0x2F -#define DISC 0x43 -#define UA 0x63 -#define UIH 0xEF - -/* Channel commands */ -#define CMD_NSC 0x09 -#define CMD_TEST 0x11 -#define CMD_PSC 0x21 -#define CMD_RLS 0x29 -#define CMD_FCOFF 0x31 -#define CMD_PN 0x41 -#define CMD_RPN 0x49 -#define CMD_FCON 0x51 -#define CMD_CLD 0x61 -#define CMD_SNC 0x69 -#define CMD_MSC 0x71 - -/* Virtual modem bits */ -#define MDM_FC 0x01 -#define MDM_RTC 0x02 -#define MDM_RTR 0x04 -#define MDM_IC 0x20 -#define MDM_DV 0x40 - -#define GSM0_SOF 0xF9 -#define GSM1_SOF 0x7E -#define GSM1_ESCAPE 0x7D -#define GSM1_ESCAPE_BITS 0x20 -#define XON 0x11 -#define XOFF 0x13 - -static const struct tty_port_operations gsm_port_ops; - -/* - * CRC table for GSM 0710 - */ - -static const u8 gsm_fcs8[256] = { - 0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75, - 0x0E, 0x9F, 0xED, 0x7C, 0x09, 0x98, 0xEA, 0x7B, - 0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A, 0xF8, 0x69, - 0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67, - 0x38, 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D, - 0x36, 0xA7, 0xD5, 0x44, 0x31, 0xA0, 0xD2, 0x43, - 0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0, 0x51, - 0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F, - 0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05, - 0x7E, 0xEF, 0x9D, 0x0C, 0x79, 0xE8, 0x9A, 0x0B, - 0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA, 0x88, 0x19, - 0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17, - 0x48, 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D, - 0x46, 0xD7, 0xA5, 0x34, 0x41, 0xD0, 0xA2, 0x33, - 0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0, 0x21, - 0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F, - 0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95, - 0xEE, 0x7F, 0x0D, 0x9C, 0xE9, 0x78, 0x0A, 0x9B, - 0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A, 0x18, 0x89, - 0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87, - 0xD8, 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD, - 0xD6, 0x47, 0x35, 0xA4, 0xD1, 0x40, 0x32, 0xA3, - 0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20, 0xB1, - 0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF, - 0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5, - 0x9E, 0x0F, 0x7D, 0xEC, 0x99, 0x08, 0x7A, 0xEB, - 0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A, 0x68, 0xF9, - 0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7, - 0xA8, 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD, - 0xA6, 0x37, 0x45, 0xD4, 0xA1, 0x30, 0x42, 0xD3, - 0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50, 0xC1, - 0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF -}; - -#define INIT_FCS 0xFF -#define GOOD_FCS 0xCF - -/** - * gsm_fcs_add - update FCS - * @fcs: Current FCS - * @c: Next data - * - * Update the FCS to include c. Uses the algorithm in the specification - * notes. - */ - -static inline u8 gsm_fcs_add(u8 fcs, u8 c) -{ - return gsm_fcs8[fcs ^ c]; -} - -/** - * gsm_fcs_add_block - update FCS for a block - * @fcs: Current FCS - * @c: buffer of data - * @len: length of buffer - * - * Update the FCS to include c. Uses the algorithm in the specification - * notes. - */ - -static inline u8 gsm_fcs_add_block(u8 fcs, u8 *c, int len) -{ - while (len--) - fcs = gsm_fcs8[fcs ^ *c++]; - return fcs; -} - -/** - * gsm_read_ea - read a byte into an EA - * @val: variable holding value - * c: byte going into the EA - * - * Processes one byte of an EA. Updates the passed variable - * and returns 1 if the EA is now completely read - */ - -static int gsm_read_ea(unsigned int *val, u8 c) -{ - /* Add the next 7 bits into the value */ - *val <<= 7; - *val |= c >> 1; - /* Was this the last byte of the EA 1 = yes*/ - return c & EA; -} - -/** - * gsm_encode_modem - encode modem data bits - * @dlci: DLCI to encode from - * - * Returns the correct GSM encoded modem status bits (6 bit field) for - * the current status of the DLCI and attached tty object - */ - -static u8 gsm_encode_modem(const struct gsm_dlci *dlci) -{ - u8 modembits = 0; - /* FC is true flow control not modem bits */ - if (dlci->throttled) - modembits |= MDM_FC; - if (dlci->modem_tx & TIOCM_DTR) - modembits |= MDM_RTC; - if (dlci->modem_tx & TIOCM_RTS) - modembits |= MDM_RTR; - if (dlci->modem_tx & TIOCM_RI) - modembits |= MDM_IC; - if (dlci->modem_tx & TIOCM_CD) - modembits |= MDM_DV; - return modembits; -} - -/** - * gsm_print_packet - display a frame for debug - * @hdr: header to print before decode - * @addr: address EA from the frame - * @cr: C/R bit from the frame - * @control: control including PF bit - * @data: following data bytes - * @dlen: length of data - * - * Displays a packet in human readable format for debugging purposes. The - * style is based on amateur radio LAP-B dump display. - */ - -static void gsm_print_packet(const char *hdr, int addr, int cr, - u8 control, const u8 *data, int dlen) -{ - if (!(debug & 1)) - return; - - printk(KERN_INFO "%s %d) %c: ", hdr, addr, "RC"[cr]); - - switch (control & ~PF) { - case SABM: - printk(KERN_CONT "SABM"); - break; - case UA: - printk(KERN_CONT "UA"); - break; - case DISC: - printk(KERN_CONT "DISC"); - break; - case DM: - printk(KERN_CONT "DM"); - break; - case UI: - printk(KERN_CONT "UI"); - break; - case UIH: - printk(KERN_CONT "UIH"); - break; - default: - if (!(control & 0x01)) { - printk(KERN_CONT "I N(S)%d N(R)%d", - (control & 0x0E) >> 1, (control & 0xE)>> 5); - } else switch (control & 0x0F) { - case RR: - printk("RR(%d)", (control & 0xE0) >> 5); - break; - case RNR: - printk("RNR(%d)", (control & 0xE0) >> 5); - break; - case REJ: - printk("REJ(%d)", (control & 0xE0) >> 5); - break; - default: - printk(KERN_CONT "[%02X]", control); - } - } - - if (control & PF) - printk(KERN_CONT "(P)"); - else - printk(KERN_CONT "(F)"); - - if (dlen) { - int ct = 0; - while (dlen--) { - if (ct % 8 == 0) - printk(KERN_CONT "\n "); - printk(KERN_CONT "%02X ", *data++); - ct++; - } - } - printk(KERN_CONT "\n"); -} - - -/* - * Link level transmission side - */ - -/** - * gsm_stuff_packet - bytestuff a packet - * @ibuf: input - * @obuf: output - * @len: length of input - * - * Expand a buffer by bytestuffing it. The worst case size change - * is doubling and the caller is responsible for handing out - * suitable sized buffers. - */ - -static int gsm_stuff_frame(const u8 *input, u8 *output, int len) -{ - int olen = 0; - while (len--) { - if (*input == GSM1_SOF || *input == GSM1_ESCAPE - || *input == XON || *input == XOFF) { - *output++ = GSM1_ESCAPE; - *output++ = *input++ ^ GSM1_ESCAPE_BITS; - olen++; - } else - *output++ = *input++; - olen++; - } - return olen; -} - -static void hex_packet(const unsigned char *p, int len) -{ - int i; - for (i = 0; i < len; i++) { - if (i && (i % 16) == 0) - printk("\n"); - printk("%02X ", *p++); - } - printk("\n"); -} - -/** - * gsm_send - send a control frame - * @gsm: our GSM mux - * @addr: address for control frame - * @cr: command/response bit - * @control: control byte including PF bit - * - * Format up and transmit a control frame. These do not go via the - * queueing logic as they should be transmitted ahead of data when - * they are needed. - * - * FIXME: Lock versus data TX path - */ - -static void gsm_send(struct gsm_mux *gsm, int addr, int cr, int control) -{ - int len; - u8 cbuf[10]; - u8 ibuf[3]; - - switch (gsm->encoding) { - case 0: - cbuf[0] = GSM0_SOF; - cbuf[1] = (addr << 2) | (cr << 1) | EA; - cbuf[2] = control; - cbuf[3] = EA; /* Length of data = 0 */ - cbuf[4] = 0xFF - gsm_fcs_add_block(INIT_FCS, cbuf + 1, 3); - cbuf[5] = GSM0_SOF; - len = 6; - break; - case 1: - case 2: - /* Control frame + packing (but not frame stuffing) in mode 1 */ - ibuf[0] = (addr << 2) | (cr << 1) | EA; - ibuf[1] = control; - ibuf[2] = 0xFF - gsm_fcs_add_block(INIT_FCS, ibuf, 2); - /* Stuffing may double the size worst case */ - len = gsm_stuff_frame(ibuf, cbuf + 1, 3); - /* Now add the SOF markers */ - cbuf[0] = GSM1_SOF; - cbuf[len + 1] = GSM1_SOF; - /* FIXME: we can omit the lead one in many cases */ - len += 2; - break; - default: - WARN_ON(1); - return; - } - gsm->output(gsm, cbuf, len); - gsm_print_packet("-->", addr, cr, control, NULL, 0); -} - -/** - * gsm_response - send a control response - * @gsm: our GSM mux - * @addr: address for control frame - * @control: control byte including PF bit - * - * Format up and transmit a link level response frame. - */ - -static inline void gsm_response(struct gsm_mux *gsm, int addr, int control) -{ - gsm_send(gsm, addr, 0, control); -} - -/** - * gsm_command - send a control command - * @gsm: our GSM mux - * @addr: address for control frame - * @control: control byte including PF bit - * - * Format up and transmit a link level command frame. - */ - -static inline void gsm_command(struct gsm_mux *gsm, int addr, int control) -{ - gsm_send(gsm, addr, 1, control); -} - -/* Data transmission */ - -#define HDR_LEN 6 /* ADDR CTRL [LEN.2] DATA FCS */ - -/** - * gsm_data_alloc - allocate data frame - * @gsm: GSM mux - * @addr: DLCI address - * @len: length excluding header and FCS - * @ctrl: control byte - * - * Allocate a new data buffer for sending frames with data. Space is left - * at the front for header bytes but that is treated as an implementation - * detail and not for the high level code to use - */ - -static struct gsm_msg *gsm_data_alloc(struct gsm_mux *gsm, u8 addr, int len, - u8 ctrl) -{ - struct gsm_msg *m = kmalloc(sizeof(struct gsm_msg) + len + HDR_LEN, - GFP_ATOMIC); - if (m == NULL) - return NULL; - m->data = m->buffer + HDR_LEN - 1; /* Allow for FCS */ - m->len = len; - m->addr = addr; - m->ctrl = ctrl; - m->next = NULL; - return m; -} - -/** - * gsm_data_kick - poke the queue - * @gsm: GSM Mux - * - * The tty device has called us to indicate that room has appeared in - * the transmit queue. Ram more data into the pipe if we have any - * - * FIXME: lock against link layer control transmissions - */ - -static void gsm_data_kick(struct gsm_mux *gsm) -{ - struct gsm_msg *msg = gsm->tx_head; - int len; - int skip_sof = 0; - - /* FIXME: We need to apply this solely to data messages */ - if (gsm->constipated) - return; - - while (gsm->tx_head != NULL) { - msg = gsm->tx_head; - if (gsm->encoding != 0) { - gsm->txframe[0] = GSM1_SOF; - len = gsm_stuff_frame(msg->data, - gsm->txframe + 1, msg->len); - gsm->txframe[len + 1] = GSM1_SOF; - len += 2; - } else { - gsm->txframe[0] = GSM0_SOF; - memcpy(gsm->txframe + 1 , msg->data, msg->len); - gsm->txframe[msg->len + 1] = GSM0_SOF; - len = msg->len + 2; - } - - if (debug & 4) { - printk("gsm_data_kick: \n"); - hex_packet(gsm->txframe, len); - } - - if (gsm->output(gsm, gsm->txframe + skip_sof, - len - skip_sof) < 0) - break; - /* FIXME: Can eliminate one SOF in many more cases */ - gsm->tx_head = msg->next; - if (gsm->tx_head == NULL) - gsm->tx_tail = NULL; - gsm->tx_bytes -= msg->len; - kfree(msg); - /* For a burst of frames skip the extra SOF within the - burst */ - skip_sof = 1; - } -} - -/** - * __gsm_data_queue - queue a UI or UIH frame - * @dlci: DLCI sending the data - * @msg: message queued - * - * Add data to the transmit queue and try and get stuff moving - * out of the mux tty if not already doing so. The Caller must hold - * the gsm tx lock. - */ - -static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) -{ - struct gsm_mux *gsm = dlci->gsm; - u8 *dp = msg->data; - u8 *fcs = dp + msg->len; - - /* Fill in the header */ - if (gsm->encoding == 0) { - if (msg->len < 128) - *--dp = (msg->len << 1) | EA; - else { - *--dp = (msg->len >> 6) | EA; - *--dp = (msg->len & 127) << 1; - } - } - - *--dp = msg->ctrl; - if (gsm->initiator) - *--dp = (msg->addr << 2) | 2 | EA; - else - *--dp = (msg->addr << 2) | EA; - *fcs = gsm_fcs_add_block(INIT_FCS, dp , msg->data - dp); - /* Ugly protocol layering violation */ - if (msg->ctrl == UI || msg->ctrl == (UI|PF)) - *fcs = gsm_fcs_add_block(*fcs, msg->data, msg->len); - *fcs = 0xFF - *fcs; - - gsm_print_packet("Q> ", msg->addr, gsm->initiator, msg->ctrl, - msg->data, msg->len); - - /* Move the header back and adjust the length, also allow for the FCS - now tacked on the end */ - msg->len += (msg->data - dp) + 1; - msg->data = dp; - - /* Add to the actual output queue */ - if (gsm->tx_tail) - gsm->tx_tail->next = msg; - else - gsm->tx_head = msg; - gsm->tx_tail = msg; - gsm->tx_bytes += msg->len; - gsm_data_kick(gsm); -} - -/** - * gsm_data_queue - queue a UI or UIH frame - * @dlci: DLCI sending the data - * @msg: message queued - * - * Add data to the transmit queue and try and get stuff moving - * out of the mux tty if not already doing so. Take the - * the gsm tx lock and dlci lock. - */ - -static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) -{ - unsigned long flags; - spin_lock_irqsave(&dlci->gsm->tx_lock, flags); - __gsm_data_queue(dlci, msg); - spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); -} - -/** - * gsm_dlci_data_output - try and push data out of a DLCI - * @gsm: mux - * @dlci: the DLCI to pull data from - * - * Pull data from a DLCI and send it into the transmit queue if there - * is data. Keep to the MRU of the mux. This path handles the usual tty - * interface which is a byte stream with optional modem data. - * - * Caller must hold the tx_lock of the mux. - */ - -static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci) -{ - struct gsm_msg *msg; - u8 *dp; - int len, size; - int h = dlci->adaption - 1; - - len = kfifo_len(dlci->fifo); - if (len == 0) - return 0; - - /* MTU/MRU count only the data bits */ - if (len > gsm->mtu) - len = gsm->mtu; - - size = len + h; - - msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); - /* FIXME: need a timer or something to kick this so it can't - get stuck with no work outstanding and no buffer free */ - if (msg == NULL) - return -ENOMEM; - dp = msg->data; - switch (dlci->adaption) { - case 1: /* Unstructured */ - break; - case 2: /* Unstructed with modem bits. Always one byte as we never - send inline break data */ - *dp += gsm_encode_modem(dlci); - len--; - break; - } - WARN_ON(kfifo_out_locked(dlci->fifo, dp , len, &dlci->lock) != len); - __gsm_data_queue(dlci, msg); - /* Bytes of data we used up */ - return size; -} - -/** - * gsm_dlci_data_output_framed - try and push data out of a DLCI - * @gsm: mux - * @dlci: the DLCI to pull data from - * - * Pull data from a DLCI and send it into the transmit queue if there - * is data. Keep to the MRU of the mux. This path handles framed data - * queued as skbuffs to the DLCI. - * - * Caller must hold the tx_lock of the mux. - */ - -static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, - struct gsm_dlci *dlci) -{ - struct gsm_msg *msg; - u8 *dp; - int len, size; - int last = 0, first = 0; - int overhead = 0; - - /* One byte per frame is used for B/F flags */ - if (dlci->adaption == 4) - overhead = 1; - - /* dlci->skb is locked by tx_lock */ - if (dlci->skb == NULL) { - dlci->skb = skb_dequeue(&dlci->skb_list); - if (dlci->skb == NULL) - return 0; - first = 1; - } - len = dlci->skb->len + overhead; - - /* MTU/MRU count only the data bits */ - if (len > gsm->mtu) { - if (dlci->adaption == 3) { - /* Over long frame, bin it */ - kfree_skb(dlci->skb); - dlci->skb = NULL; - return 0; - } - len = gsm->mtu; - } else - last = 1; - - size = len + overhead; - msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); - - /* FIXME: need a timer or something to kick this so it can't - get stuck with no work outstanding and no buffer free */ - if (msg == NULL) - return -ENOMEM; - dp = msg->data; - - if (dlci->adaption == 4) { /* Interruptible framed (Packetised Data) */ - /* Flag byte to carry the start/end info */ - *dp++ = last << 7 | first << 6 | 1; /* EA */ - len--; - } - memcpy(dp, skb_pull(dlci->skb, len), len); - __gsm_data_queue(dlci, msg); - if (last) - dlci->skb = NULL; - return size; -} - -/** - * gsm_dlci_data_sweep - look for data to send - * @gsm: the GSM mux - * - * Sweep the GSM mux channels in priority order looking for ones with - * data to send. We could do with optimising this scan a bit. We aim - * to fill the queue totally or up to TX_THRESH_HI bytes. Once we hit - * TX_THRESH_LO we get called again - * - * FIXME: We should round robin between groups and in theory you can - * renegotiate DLCI priorities with optional stuff. Needs optimising. - */ - -static void gsm_dlci_data_sweep(struct gsm_mux *gsm) -{ - int len; - /* Priority ordering: We should do priority with RR of the groups */ - int i = 1; - - while (i < NUM_DLCI) { - struct gsm_dlci *dlci; - - if (gsm->tx_bytes > TX_THRESH_HI) - break; - dlci = gsm->dlci[i]; - if (dlci == NULL || dlci->constipated) { - i++; - continue; - } - if (dlci->adaption < 3) - len = gsm_dlci_data_output(gsm, dlci); - else - len = gsm_dlci_data_output_framed(gsm, dlci); - if (len < 0) - break; - /* DLCI empty - try the next */ - if (len == 0) - i++; - } -} - -/** - * gsm_dlci_data_kick - transmit if possible - * @dlci: DLCI to kick - * - * Transmit data from this DLCI if the queue is empty. We can't rely on - * a tty wakeup except when we filled the pipe so we need to fire off - * new data ourselves in other cases. - */ - -static void gsm_dlci_data_kick(struct gsm_dlci *dlci) -{ - unsigned long flags; - - spin_lock_irqsave(&dlci->gsm->tx_lock, flags); - /* If we have nothing running then we need to fire up */ - if (dlci->gsm->tx_bytes == 0) - gsm_dlci_data_output(dlci->gsm, dlci); - else if (dlci->gsm->tx_bytes < TX_THRESH_LO) - gsm_dlci_data_sweep(dlci->gsm); - spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); -} - -/* - * Control message processing - */ - - -/** - * gsm_control_reply - send a response frame to a control - * @gsm: gsm channel - * @cmd: the command to use - * @data: data to follow encoded info - * @dlen: length of data - * - * Encode up and queue a UI/UIH frame containing our response. - */ - -static void gsm_control_reply(struct gsm_mux *gsm, int cmd, u8 *data, - int dlen) -{ - struct gsm_msg *msg; - msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->ftype); - msg->data[0] = (cmd & 0xFE) << 1 | EA; /* Clear C/R */ - msg->data[1] = (dlen << 1) | EA; - memcpy(msg->data + 2, data, dlen); - gsm_data_queue(gsm->dlci[0], msg); -} - -/** - * gsm_process_modem - process received modem status - * @tty: virtual tty bound to the DLCI - * @dlci: DLCI to affect - * @modem: modem bits (full EA) - * - * Used when a modem control message or line state inline in adaption - * layer 2 is processed. Sort out the local modem state and throttles - */ - -static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci, - u32 modem) -{ - int mlines = 0; - u8 brk = modem >> 6; - - /* Flow control/ready to communicate */ - if (modem & MDM_FC) { - /* Need to throttle our output on this device */ - dlci->constipated = 1; - } - if (modem & MDM_RTC) { - mlines |= TIOCM_DSR | TIOCM_DTR; - dlci->constipated = 0; - gsm_dlci_data_kick(dlci); - } - /* Map modem bits */ - if (modem & MDM_RTR) - mlines |= TIOCM_RTS | TIOCM_CTS; - if (modem & MDM_IC) - mlines |= TIOCM_RI; - if (modem & MDM_DV) - mlines |= TIOCM_CD; - - /* Carrier drop -> hangup */ - if (tty) { - if ((mlines & TIOCM_CD) == 0 && (dlci->modem_rx & TIOCM_CD)) - if (!(tty->termios->c_cflag & CLOCAL)) - tty_hangup(tty); - if (brk & 0x01) - tty_insert_flip_char(tty, 0, TTY_BREAK); - } - dlci->modem_rx = mlines; -} - -/** - * gsm_control_modem - modem status received - * @gsm: GSM channel - * @data: data following command - * @clen: command length - * - * We have received a modem status control message. This is used by - * the GSM mux protocol to pass virtual modem line status and optionally - * to indicate break signals. Unpack it, convert to Linux representation - * and if need be stuff a break message down the tty. - */ - -static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen) -{ - unsigned int addr = 0; - unsigned int modem = 0; - struct gsm_dlci *dlci; - int len = clen; - u8 *dp = data; - struct tty_struct *tty; - - while (gsm_read_ea(&addr, *dp++) == 0) { - len--; - if (len == 0) - return; - } - /* Must be at least one byte following the EA */ - len--; - if (len <= 0) - return; - - addr >>= 1; - /* Closed port, or invalid ? */ - if (addr == 0 || addr >= NUM_DLCI || gsm->dlci[addr] == NULL) - return; - dlci = gsm->dlci[addr]; - - while (gsm_read_ea(&modem, *dp++) == 0) { - len--; - if (len == 0) - return; - } - tty = tty_port_tty_get(&dlci->port); - gsm_process_modem(tty, dlci, modem); - if (tty) { - tty_wakeup(tty); - tty_kref_put(tty); - } - gsm_control_reply(gsm, CMD_MSC, data, clen); -} - -/** - * gsm_control_rls - remote line status - * @gsm: GSM channel - * @data: data bytes - * @clen: data length - * - * The modem sends us a two byte message on the control channel whenever - * it wishes to send us an error state from the virtual link. Stuff - * this into the uplink tty if present - */ - -static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen) -{ - struct tty_struct *tty; - unsigned int addr = 0 ; - u8 bits; - int len = clen; - u8 *dp = data; - - while (gsm_read_ea(&addr, *dp++) == 0) { - len--; - if (len == 0) - return; - } - /* Must be at least one byte following ea */ - len--; - if (len <= 0) - return; - addr >>= 1; - /* Closed port, or invalid ? */ - if (addr == 0 || addr >= NUM_DLCI || gsm->dlci[addr] == NULL) - return; - /* No error ? */ - bits = *dp; - if ((bits & 1) == 0) - return; - /* See if we have an uplink tty */ - tty = tty_port_tty_get(&gsm->dlci[addr]->port); - - if (tty) { - if (bits & 2) - tty_insert_flip_char(tty, 0, TTY_OVERRUN); - if (bits & 4) - tty_insert_flip_char(tty, 0, TTY_PARITY); - if (bits & 8) - tty_insert_flip_char(tty, 0, TTY_FRAME); - tty_flip_buffer_push(tty); - tty_kref_put(tty); - } - gsm_control_reply(gsm, CMD_RLS, data, clen); -} - -static void gsm_dlci_begin_close(struct gsm_dlci *dlci); - -/** - * gsm_control_message - DLCI 0 control processing - * @gsm: our GSM mux - * @command: the command EA - * @data: data beyond the command/length EAs - * @clen: length - * - * Input processor for control messages from the other end of the link. - * Processes the incoming request and queues a response frame or an - * NSC response if not supported - */ - -static void gsm_control_message(struct gsm_mux *gsm, unsigned int command, - u8 *data, int clen) -{ - u8 buf[1]; - switch (command) { - case CMD_CLD: { - struct gsm_dlci *dlci = gsm->dlci[0]; - /* Modem wishes to close down */ - if (dlci) { - dlci->dead = 1; - gsm->dead = 1; - gsm_dlci_begin_close(dlci); - } - } - break; - case CMD_TEST: - /* Modem wishes to test, reply with the data */ - gsm_control_reply(gsm, CMD_TEST, data, clen); - break; - case CMD_FCON: - /* Modem wants us to STFU */ - gsm->constipated = 1; - gsm_control_reply(gsm, CMD_FCON, NULL, 0); - break; - case CMD_FCOFF: - /* Modem can accept data again */ - gsm->constipated = 0; - gsm_control_reply(gsm, CMD_FCOFF, NULL, 0); - /* Kick the link in case it is idling */ - gsm_data_kick(gsm); - break; - case CMD_MSC: - /* Out of band modem line change indicator for a DLCI */ - gsm_control_modem(gsm, data, clen); - break; - case CMD_RLS: - /* Out of band error reception for a DLCI */ - gsm_control_rls(gsm, data, clen); - break; - case CMD_PSC: - /* Modem wishes to enter power saving state */ - gsm_control_reply(gsm, CMD_PSC, NULL, 0); - break; - /* Optional unsupported commands */ - case CMD_PN: /* Parameter negotiation */ - case CMD_RPN: /* Remote port negotation */ - case CMD_SNC: /* Service negotation command */ - default: - /* Reply to bad commands with an NSC */ - buf[0] = command; - gsm_control_reply(gsm, CMD_NSC, buf, 1); - break; - } -} - -/** - * gsm_control_response - process a response to our control - * @gsm: our GSM mux - * @command: the command (response) EA - * @data: data beyond the command/length EA - * @clen: length - * - * Process a response to an outstanding command. We only allow a single - * control message in flight so this is fairly easy. All the clean up - * is done by the caller, we just update the fields, flag it as done - * and return - */ - -static void gsm_control_response(struct gsm_mux *gsm, unsigned int command, - u8 *data, int clen) -{ - struct gsm_control *ctrl; - unsigned long flags; - - spin_lock_irqsave(&gsm->control_lock, flags); - - ctrl = gsm->pending_cmd; - /* Does the reply match our command */ - command |= 1; - if (ctrl != NULL && (command == ctrl->cmd || command == CMD_NSC)) { - /* Our command was replied to, kill the retry timer */ - del_timer(&gsm->t2_timer); - gsm->pending_cmd = NULL; - /* Rejected by the other end */ - if (command == CMD_NSC) - ctrl->error = -EOPNOTSUPP; - ctrl->done = 1; - wake_up(&gsm->event); - } - spin_unlock_irqrestore(&gsm->control_lock, flags); -} - -/** - * gsm_control_transmit - send control packet - * @gsm: gsm mux - * @ctrl: frame to send - * - * Send out a pending control command (called under control lock) - */ - -static void gsm_control_transmit(struct gsm_mux *gsm, struct gsm_control *ctrl) -{ - struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 1, - gsm->ftype|PF); - if (msg == NULL) - return; - msg->data[0] = (ctrl->cmd << 1) | 2 | EA; /* command */ - memcpy(msg->data + 1, ctrl->data, ctrl->len); - gsm_data_queue(gsm->dlci[0], msg); -} - -/** - * gsm_control_retransmit - retransmit a control frame - * @data: pointer to our gsm object - * - * Called off the T2 timer expiry in order to retransmit control frames - * that have been lost in the system somewhere. The control_lock protects - * us from colliding with another sender or a receive completion event. - * In that situation the timer may still occur in a small window but - * gsm->pending_cmd will be NULL and we just let the timer expire. - */ - -static void gsm_control_retransmit(unsigned long data) -{ - struct gsm_mux *gsm = (struct gsm_mux *)data; - struct gsm_control *ctrl; - unsigned long flags; - spin_lock_irqsave(&gsm->control_lock, flags); - ctrl = gsm->pending_cmd; - if (ctrl) { - gsm->cretries--; - if (gsm->cretries == 0) { - gsm->pending_cmd = NULL; - ctrl->error = -ETIMEDOUT; - ctrl->done = 1; - spin_unlock_irqrestore(&gsm->control_lock, flags); - wake_up(&gsm->event); - return; - } - gsm_control_transmit(gsm, ctrl); - mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100); - } - spin_unlock_irqrestore(&gsm->control_lock, flags); -} - -/** - * gsm_control_send - send a control frame on DLCI 0 - * @gsm: the GSM channel - * @command: command to send including CR bit - * @data: bytes of data (must be kmalloced) - * @len: length of the block to send - * - * Queue and dispatch a control command. Only one command can be - * active at a time. In theory more can be outstanding but the matching - * gets really complicated so for now stick to one outstanding. - */ - -static struct gsm_control *gsm_control_send(struct gsm_mux *gsm, - unsigned int command, u8 *data, int clen) -{ - struct gsm_control *ctrl = kzalloc(sizeof(struct gsm_control), - GFP_KERNEL); - unsigned long flags; - if (ctrl == NULL) - return NULL; -retry: - wait_event(gsm->event, gsm->pending_cmd == NULL); - spin_lock_irqsave(&gsm->control_lock, flags); - if (gsm->pending_cmd != NULL) { - spin_unlock_irqrestore(&gsm->control_lock, flags); - goto retry; - } - ctrl->cmd = command; - ctrl->data = data; - ctrl->len = clen; - gsm->pending_cmd = ctrl; - gsm->cretries = gsm->n2; - mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100); - gsm_control_transmit(gsm, ctrl); - spin_unlock_irqrestore(&gsm->control_lock, flags); - return ctrl; -} - -/** - * gsm_control_wait - wait for a control to finish - * @gsm: GSM mux - * @control: control we are waiting on - * - * Waits for the control to complete or time out. Frees any used - * resources and returns 0 for success, or an error if the remote - * rejected or ignored the request. - */ - -static int gsm_control_wait(struct gsm_mux *gsm, struct gsm_control *control) -{ - int err; - wait_event(gsm->event, control->done == 1); - err = control->error; - kfree(control); - return err; -} - - -/* - * DLCI level handling: Needs krefs - */ - -/* - * State transitions and timers - */ - -/** - * gsm_dlci_close - a DLCI has closed - * @dlci: DLCI that closed - * - * Perform processing when moving a DLCI into closed state. If there - * is an attached tty this is hung up - */ - -static void gsm_dlci_close(struct gsm_dlci *dlci) -{ - del_timer(&dlci->t1); - if (debug & 8) - printk("DLCI %d goes closed.\n", dlci->addr); - dlci->state = DLCI_CLOSED; - if (dlci->addr != 0) { - struct tty_struct *tty = tty_port_tty_get(&dlci->port); - if (tty) { - tty_hangup(tty); - tty_kref_put(tty); - } - kfifo_reset(dlci->fifo); - } else - dlci->gsm->dead = 1; - wake_up(&dlci->gsm->event); - /* A DLCI 0 close is a MUX termination so we need to kick that - back to userspace somehow */ -} - -/** - * gsm_dlci_open - a DLCI has opened - * @dlci: DLCI that opened - * - * Perform processing when moving a DLCI into open state. - */ - -static void gsm_dlci_open(struct gsm_dlci *dlci) -{ - /* Note that SABM UA .. SABM UA first UA lost can mean that we go - open -> open */ - del_timer(&dlci->t1); - /* This will let a tty open continue */ - dlci->state = DLCI_OPEN; - if (debug & 8) - printk("DLCI %d goes open.\n", dlci->addr); - wake_up(&dlci->gsm->event); -} - -/** - * gsm_dlci_t1 - T1 timer expiry - * @dlci: DLCI that opened - * - * The T1 timer handles retransmits of control frames (essentially of - * SABM and DISC). We resend the command until the retry count runs out - * in which case an opening port goes back to closed and a closing port - * is simply put into closed state (any further frames from the other - * end will get a DM response) - */ - -static void gsm_dlci_t1(unsigned long data) -{ - struct gsm_dlci *dlci = (struct gsm_dlci *)data; - struct gsm_mux *gsm = dlci->gsm; - - switch (dlci->state) { - case DLCI_OPENING: - dlci->retries--; - if (dlci->retries) { - gsm_command(dlci->gsm, dlci->addr, SABM|PF); - mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); - } else - gsm_dlci_close(dlci); - break; - case DLCI_CLOSING: - dlci->retries--; - if (dlci->retries) { - gsm_command(dlci->gsm, dlci->addr, DISC|PF); - mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); - } else - gsm_dlci_close(dlci); - break; - } -} - -/** - * gsm_dlci_begin_open - start channel open procedure - * @dlci: DLCI to open - * - * Commence opening a DLCI from the Linux side. We issue SABM messages - * to the modem which should then reply with a UA, at which point we - * will move into open state. Opening is done asynchronously with retry - * running off timers and the responses. - */ - -static void gsm_dlci_begin_open(struct gsm_dlci *dlci) -{ - struct gsm_mux *gsm = dlci->gsm; - if (dlci->state == DLCI_OPEN || dlci->state == DLCI_OPENING) - return; - dlci->retries = gsm->n2; - dlci->state = DLCI_OPENING; - gsm_command(dlci->gsm, dlci->addr, SABM|PF); - mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); -} - -/** - * gsm_dlci_begin_close - start channel open procedure - * @dlci: DLCI to open - * - * Commence closing a DLCI from the Linux side. We issue DISC messages - * to the modem which should then reply with a UA, at which point we - * will move into closed state. Closing is done asynchronously with retry - * off timers. We may also receive a DM reply from the other end which - * indicates the channel was already closed. - */ - -static void gsm_dlci_begin_close(struct gsm_dlci *dlci) -{ - struct gsm_mux *gsm = dlci->gsm; - if (dlci->state == DLCI_CLOSED || dlci->state == DLCI_CLOSING) - return; - dlci->retries = gsm->n2; - dlci->state = DLCI_CLOSING; - gsm_command(dlci->gsm, dlci->addr, DISC|PF); - mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); -} - -/** - * gsm_dlci_data - data arrived - * @dlci: channel - * @data: block of bytes received - * @len: length of received block - * - * A UI or UIH frame has arrived which contains data for a channel - * other than the control channel. If the relevant virtual tty is - * open we shovel the bits down it, if not we drop them. - */ - -static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int len) -{ - /* krefs .. */ - struct tty_port *port = &dlci->port; - struct tty_struct *tty = tty_port_tty_get(port); - unsigned int modem = 0; - - if (debug & 16) - printk("%d bytes for tty %p\n", len, tty); - if (tty) { - switch (dlci->adaption) { - /* Unsupported types */ - /* Packetised interruptible data */ - case 4: - break; - /* Packetised uininterruptible voice/data */ - case 3: - break; - /* Asynchronous serial with line state in each frame */ - case 2: - while (gsm_read_ea(&modem, *data++) == 0) { - len--; - if (len == 0) - return; - } - gsm_process_modem(tty, dlci, modem); - /* Line state will go via DLCI 0 controls only */ - case 1: - default: - tty_insert_flip_string(tty, data, len); - tty_flip_buffer_push(tty); - } - tty_kref_put(tty); - } -} - -/** - * gsm_dlci_control - data arrived on control channel - * @dlci: channel - * @data: block of bytes received - * @len: length of received block - * - * A UI or UIH frame has arrived which contains data for DLCI 0 the - * control channel. This should contain a command EA followed by - * control data bytes. The command EA contains a command/response bit - * and we divide up the work accordingly. - */ - -static void gsm_dlci_command(struct gsm_dlci *dlci, u8 *data, int len) -{ - /* See what command is involved */ - unsigned int command = 0; - while (len-- > 0) { - if (gsm_read_ea(&command, *data++) == 1) { - int clen = *data++; - len--; - /* FIXME: this is properly an EA */ - clen >>= 1; - /* Malformed command ? */ - if (clen > len) - return; - if (command & 1) - gsm_control_message(dlci->gsm, command, - data, clen); - else - gsm_control_response(dlci->gsm, command, - data, clen); - return; - } - } -} - -/* - * Allocate/Free DLCI channels - */ - -/** - * gsm_dlci_alloc - allocate a DLCI - * @gsm: GSM mux - * @addr: address of the DLCI - * - * Allocate and install a new DLCI object into the GSM mux. - * - * FIXME: review locking races - */ - -static struct gsm_dlci *gsm_dlci_alloc(struct gsm_mux *gsm, int addr) -{ - struct gsm_dlci *dlci = kzalloc(sizeof(struct gsm_dlci), GFP_ATOMIC); - if (dlci == NULL) - return NULL; - spin_lock_init(&dlci->lock); - dlci->fifo = &dlci->_fifo; - if (kfifo_alloc(&dlci->_fifo, 4096, GFP_KERNEL) < 0) { - kfree(dlci); - return NULL; - } - - skb_queue_head_init(&dlci->skb_list); - init_timer(&dlci->t1); - dlci->t1.function = gsm_dlci_t1; - dlci->t1.data = (unsigned long)dlci; - tty_port_init(&dlci->port); - dlci->port.ops = &gsm_port_ops; - dlci->gsm = gsm; - dlci->addr = addr; - dlci->adaption = gsm->adaption; - dlci->state = DLCI_CLOSED; - if (addr) - dlci->data = gsm_dlci_data; - else - dlci->data = gsm_dlci_command; - gsm->dlci[addr] = dlci; - return dlci; -} - -/** - * gsm_dlci_free - release DLCI - * @dlci: DLCI to destroy - * - * Free up a DLCI. Currently to keep the lifetime rules sane we only - * clean up DLCI objects when the MUX closes rather than as the port - * is closed down on both the tty and mux levels. - * - * Can sleep. - */ -static void gsm_dlci_free(struct gsm_dlci *dlci) -{ - struct tty_struct *tty = tty_port_tty_get(&dlci->port); - if (tty) { - tty_vhangup(tty); - tty_kref_put(tty); - } - del_timer_sync(&dlci->t1); - dlci->gsm->dlci[dlci->addr] = NULL; - kfifo_free(dlci->fifo); - kfree(dlci); -} - - -/* - * LAPBish link layer logic - */ - -/** - * gsm_queue - a GSM frame is ready to process - * @gsm: pointer to our gsm mux - * - * At this point in time a frame has arrived and been demangled from - * the line encoding. All the differences between the encodings have - * been handled below us and the frame is unpacked into the structures. - * The fcs holds the header FCS but any data FCS must be added here. - */ - -static void gsm_queue(struct gsm_mux *gsm) -{ - struct gsm_dlci *dlci; - u8 cr; - int address; - /* We have to sneak a look at the packet body to do the FCS. - A somewhat layering violation in the spec */ - - if ((gsm->control & ~PF) == UI) - gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf, gsm->len); - if (gsm->fcs != GOOD_FCS) { - gsm->bad_fcs++; - if (debug & 4) - printk("BAD FCS %02x\n", gsm->fcs); - return; - } - address = gsm->address >> 1; - if (address >= NUM_DLCI) - goto invalid; - - cr = gsm->address & 1; /* C/R bit */ - - gsm_print_packet("<--", address, cr, gsm->control, gsm->buf, gsm->len); - - cr ^= 1 - gsm->initiator; /* Flip so 1 always means command */ - dlci = gsm->dlci[address]; - - switch (gsm->control) { - case SABM|PF: - if (cr == 0) - goto invalid; - if (dlci == NULL) - dlci = gsm_dlci_alloc(gsm, address); - if (dlci == NULL) - return; - if (dlci->dead) - gsm_response(gsm, address, DM); - else { - gsm_response(gsm, address, UA); - gsm_dlci_open(dlci); - } - break; - case DISC|PF: - if (cr == 0) - goto invalid; - if (dlci == NULL || dlci->state == DLCI_CLOSED) { - gsm_response(gsm, address, DM); - return; - } - /* Real close complete */ - gsm_response(gsm, address, UA); - gsm_dlci_close(dlci); - break; - case UA: - case UA|PF: - if (cr == 0 || dlci == NULL) - break; - switch (dlci->state) { - case DLCI_CLOSING: - gsm_dlci_close(dlci); - break; - case DLCI_OPENING: - gsm_dlci_open(dlci); - break; - } - break; - case DM: /* DM can be valid unsolicited */ - case DM|PF: - if (cr) - goto invalid; - if (dlci == NULL) - return; - gsm_dlci_close(dlci); - break; - case UI: - case UI|PF: - case UIH: - case UIH|PF: -#if 0 - if (cr) - goto invalid; -#endif - if (dlci == NULL || dlci->state != DLCI_OPEN) { - gsm_command(gsm, address, DM|PF); - return; - } - dlci->data(dlci, gsm->buf, gsm->len); - break; - default: - goto invalid; - } - return; -invalid: - gsm->malformed++; - return; -} - - -/** - * gsm0_receive - perform processing for non-transparency - * @gsm: gsm data for this ldisc instance - * @c: character - * - * Receive bytes in gsm mode 0 - */ - -static void gsm0_receive(struct gsm_mux *gsm, unsigned char c) -{ - switch (gsm->state) { - case GSM_SEARCH: /* SOF marker */ - if (c == GSM0_SOF) { - gsm->state = GSM_ADDRESS; - gsm->address = 0; - gsm->len = 0; - gsm->fcs = INIT_FCS; - } - break; /* Address EA */ - case GSM_ADDRESS: - gsm->fcs = gsm_fcs_add(gsm->fcs, c); - if (gsm_read_ea(&gsm->address, c)) - gsm->state = GSM_CONTROL; - break; - case GSM_CONTROL: /* Control Byte */ - gsm->fcs = gsm_fcs_add(gsm->fcs, c); - gsm->control = c; - gsm->state = GSM_LEN; - break; - case GSM_LEN: /* Length EA */ - gsm->fcs = gsm_fcs_add(gsm->fcs, c); - if (gsm_read_ea(&gsm->len, c)) { - if (gsm->len > gsm->mru) { - gsm->bad_size++; - gsm->state = GSM_SEARCH; - break; - } - gsm->count = 0; - gsm->state = GSM_DATA; - } - break; - case GSM_DATA: /* Data */ - gsm->buf[gsm->count++] = c; - if (gsm->count == gsm->len) - gsm->state = GSM_FCS; - break; - case GSM_FCS: /* FCS follows the packet */ - gsm->fcs = c; - gsm_queue(gsm); - /* And then back for the next frame */ - gsm->state = GSM_SEARCH; - break; - } -} - -/** - * gsm0_receive - perform processing for non-transparency - * @gsm: gsm data for this ldisc instance - * @c: character - * - * Receive bytes in mode 1 (Advanced option) - */ - -static void gsm1_receive(struct gsm_mux *gsm, unsigned char c) -{ - if (c == GSM1_SOF) { - /* EOF is only valid in frame if we have got to the data state - and received at least one byte (the FCS) */ - if (gsm->state == GSM_DATA && gsm->count) { - /* Extract the FCS */ - gsm->count--; - gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->buf[gsm->count]); - gsm->len = gsm->count; - gsm_queue(gsm); - gsm->state = GSM_START; - return; - } - /* Any partial frame was a runt so go back to start */ - if (gsm->state != GSM_START) { - gsm->malformed++; - gsm->state = GSM_START; - } - /* A SOF in GSM_START means we are still reading idling or - framing bytes */ - return; - } - - if (c == GSM1_ESCAPE) { - gsm->escape = 1; - return; - } - - /* Only an unescaped SOF gets us out of GSM search */ - if (gsm->state == GSM_SEARCH) - return; - - if (gsm->escape) { - c ^= GSM1_ESCAPE_BITS; - gsm->escape = 0; - } - switch (gsm->state) { - case GSM_START: /* First byte after SOF */ - gsm->address = 0; - gsm->state = GSM_ADDRESS; - gsm->fcs = INIT_FCS; - /* Drop through */ - case GSM_ADDRESS: /* Address continuation */ - gsm->fcs = gsm_fcs_add(gsm->fcs, c); - if (gsm_read_ea(&gsm->address, c)) - gsm->state = GSM_CONTROL; - break; - case GSM_CONTROL: /* Control Byte */ - gsm->fcs = gsm_fcs_add(gsm->fcs, c); - gsm->control = c; - gsm->count = 0; - gsm->state = GSM_DATA; - break; - case GSM_DATA: /* Data */ - if (gsm->count > gsm->mru ) { /* Allow one for the FCS */ - gsm->state = GSM_OVERRUN; - gsm->bad_size++; - } else - gsm->buf[gsm->count++] = c; - break; - case GSM_OVERRUN: /* Over-long - eg a dropped SOF */ - break; - } -} - -/** - * gsm_error - handle tty error - * @gsm: ldisc data - * @data: byte received (may be invalid) - * @flag: error received - * - * Handle an error in the receipt of data for a frame. Currently we just - * go back to hunting for a SOF. - * - * FIXME: better diagnostics ? - */ - -static void gsm_error(struct gsm_mux *gsm, - unsigned char data, unsigned char flag) -{ - gsm->state = GSM_SEARCH; - gsm->io_error++; -} - -/** - * gsm_cleanup_mux - generic GSM protocol cleanup - * @gsm: our mux - * - * Clean up the bits of the mux which are the same for all framing - * protocols. Remove the mux from the mux table, stop all the timers - * and then shut down each device hanging up the channels as we go. - */ - -void gsm_cleanup_mux(struct gsm_mux *gsm) -{ - int i; - struct gsm_dlci *dlci = gsm->dlci[0]; - struct gsm_msg *txq; - - gsm->dead = 1; - - spin_lock(&gsm_mux_lock); - for (i = 0; i < MAX_MUX; i++) { - if (gsm_mux[i] == gsm) { - gsm_mux[i] = NULL; - break; - } - } - spin_unlock(&gsm_mux_lock); - WARN_ON(i == MAX_MUX); - - del_timer_sync(&gsm->t2_timer); - /* Now we are sure T2 has stopped */ - if (dlci) { - dlci->dead = 1; - gsm_dlci_begin_close(dlci); - wait_event_interruptible(gsm->event, - dlci->state == DLCI_CLOSED); - } - /* Free up any link layer users */ - for (i = 0; i < NUM_DLCI; i++) - if (gsm->dlci[i]) - gsm_dlci_free(gsm->dlci[i]); - /* Now wipe the queues */ - for (txq = gsm->tx_head; txq != NULL; txq = gsm->tx_head) { - gsm->tx_head = txq->next; - kfree(txq); - } - gsm->tx_tail = NULL; -} -EXPORT_SYMBOL_GPL(gsm_cleanup_mux); - -/** - * gsm_activate_mux - generic GSM setup - * @gsm: our mux - * - * Set up the bits of the mux which are the same for all framing - * protocols. Add the mux to the mux table so it can be opened and - * finally kick off connecting to DLCI 0 on the modem. - */ - -int gsm_activate_mux(struct gsm_mux *gsm) -{ - struct gsm_dlci *dlci; - int i = 0; - - init_timer(&gsm->t2_timer); - gsm->t2_timer.function = gsm_control_retransmit; - gsm->t2_timer.data = (unsigned long)gsm; - init_waitqueue_head(&gsm->event); - spin_lock_init(&gsm->control_lock); - spin_lock_init(&gsm->tx_lock); - - if (gsm->encoding == 0) - gsm->receive = gsm0_receive; - else - gsm->receive = gsm1_receive; - gsm->error = gsm_error; - - spin_lock(&gsm_mux_lock); - for (i = 0; i < MAX_MUX; i++) { - if (gsm_mux[i] == NULL) { - gsm_mux[i] = gsm; - break; - } - } - spin_unlock(&gsm_mux_lock); - if (i == MAX_MUX) - return -EBUSY; - - dlci = gsm_dlci_alloc(gsm, 0); - if (dlci == NULL) - return -ENOMEM; - gsm->dead = 0; /* Tty opens are now permissible */ - return 0; -} -EXPORT_SYMBOL_GPL(gsm_activate_mux); - -/** - * gsm_free_mux - free up a mux - * @mux: mux to free - * - * Dispose of allocated resources for a dead mux. No refcounting - * at present so the mux must be truely dead. - */ -void gsm_free_mux(struct gsm_mux *gsm) -{ - kfree(gsm->txframe); - kfree(gsm->buf); - kfree(gsm); -} -EXPORT_SYMBOL_GPL(gsm_free_mux); - -/** - * gsm_alloc_mux - allocate a mux - * - * Creates a new mux ready for activation. - */ - -struct gsm_mux *gsm_alloc_mux(void) -{ - struct gsm_mux *gsm = kzalloc(sizeof(struct gsm_mux), GFP_KERNEL); - if (gsm == NULL) - return NULL; - gsm->buf = kmalloc(MAX_MRU + 1, GFP_KERNEL); - if (gsm->buf == NULL) { - kfree(gsm); - return NULL; - } - gsm->txframe = kmalloc(2 * MAX_MRU + 2, GFP_KERNEL); - if (gsm->txframe == NULL) { - kfree(gsm->buf); - kfree(gsm); - return NULL; - } - spin_lock_init(&gsm->lock); - - gsm->t1 = T1; - gsm->t2 = T2; - gsm->n2 = N2; - gsm->ftype = UIH; - gsm->initiator = 0; - gsm->adaption = 1; - gsm->encoding = 1; - gsm->mru = 64; /* Default to encoding 1 so these should be 64 */ - gsm->mtu = 64; - gsm->dead = 1; /* Avoid early tty opens */ - - return gsm; -} -EXPORT_SYMBOL_GPL(gsm_alloc_mux); - - - - -/** - * gsmld_output - write to link - * @gsm: our mux - * @data: bytes to output - * @len: size - * - * Write a block of data from the GSM mux to the data channel. This - * will eventually be serialized from above but at the moment isn't. - */ - -static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len) -{ - if (tty_write_room(gsm->tty) < len) { - set_bit(TTY_DO_WRITE_WAKEUP, &gsm->tty->flags); - return -ENOSPC; - } - if (debug & 4) { - printk("-->%d bytes out\n", len); - hex_packet(data, len); - } - gsm->tty->ops->write(gsm->tty, data, len); - return len; -} - -/** - * gsmld_attach_gsm - mode set up - * @tty: our tty structure - * @gsm: our mux - * - * Set up the MUX for basic mode and commence connecting to the - * modem. Currently called from the line discipline set up but - * will need moving to an ioctl path. - */ - -static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) -{ - int ret; - - gsm->tty = tty_kref_get(tty); - gsm->output = gsmld_output; - ret = gsm_activate_mux(gsm); - if (ret != 0) - tty_kref_put(gsm->tty); - return ret; -} - - -/** - * gsmld_detach_gsm - stop doing 0710 mux - * @tty: tty atttached to the mux - * @gsm: mux - * - * Shutdown and then clean up the resources used by the line discipline - */ - -static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) -{ - WARN_ON(tty != gsm->tty); - gsm_cleanup_mux(gsm); - tty_kref_put(gsm->tty); - gsm->tty = NULL; -} - -static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) -{ - struct gsm_mux *gsm = tty->disc_data; - const unsigned char *dp; - char *f; - int i; - char buf[64]; - char flags; - - if (debug & 4) { - printk("Inbytes %dd\n", count); - hex_packet(cp, count); - } - - for (i = count, dp = cp, f = fp; i; i--, dp++) { - flags = *f++; - switch (flags) { - case TTY_NORMAL: - gsm->receive(gsm, *dp); - break; - case TTY_OVERRUN: - case TTY_BREAK: - case TTY_PARITY: - case TTY_FRAME: - gsm->error(gsm, *dp, flags); - break; - default: - printk(KERN_ERR "%s: unknown flag %d\n", - tty_name(tty, buf), flags); - break; - } - } - /* FASYNC if needed ? */ - /* If clogged call tty_throttle(tty); */ -} - -/** - * gsmld_chars_in_buffer - report available bytes - * @tty: tty device - * - * Report the number of characters buffered to be delivered to user - * at this instant in time. - * - * Locking: gsm lock - */ - -static ssize_t gsmld_chars_in_buffer(struct tty_struct *tty) -{ - return 0; -} - -/** - * gsmld_flush_buffer - clean input queue - * @tty: terminal device - * - * Flush the input buffer. Called when the line discipline is - * being closed, when the tty layer wants the buffer flushed (eg - * at hangup). - */ - -static void gsmld_flush_buffer(struct tty_struct *tty) -{ -} - -/** - * gsmld_close - close the ldisc for this tty - * @tty: device - * - * Called from the terminal layer when this line discipline is - * being shut down, either because of a close or becsuse of a - * discipline change. The function will not be called while other - * ldisc methods are in progress. - */ - -static void gsmld_close(struct tty_struct *tty) -{ - struct gsm_mux *gsm = tty->disc_data; - - gsmld_detach_gsm(tty, gsm); - - gsmld_flush_buffer(tty); - /* Do other clean up here */ - gsm_free_mux(gsm); -} - -/** - * gsmld_open - open an ldisc - * @tty: terminal to open - * - * Called when this line discipline is being attached to the - * terminal device. Can sleep. Called serialized so that no - * other events will occur in parallel. No further open will occur - * until a close. - */ - -static int gsmld_open(struct tty_struct *tty) -{ - struct gsm_mux *gsm; - - if (tty->ops->write == NULL) - return -EINVAL; - - /* Attach our ldisc data */ - gsm = gsm_alloc_mux(); - if (gsm == NULL) - return -ENOMEM; - - tty->disc_data = gsm; - tty->receive_room = 65536; - - /* Attach the initial passive connection */ - gsm->encoding = 1; - return gsmld_attach_gsm(tty, gsm); -} - -/** - * gsmld_write_wakeup - asynchronous I/O notifier - * @tty: tty device - * - * Required for the ptys, serial driver etc. since processes - * that attach themselves to the master and rely on ASYNC - * IO must be woken up - */ - -static void gsmld_write_wakeup(struct tty_struct *tty) -{ - struct gsm_mux *gsm = tty->disc_data; - unsigned long flags; - - /* Queue poll */ - clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); - gsm_data_kick(gsm); - if (gsm->tx_bytes < TX_THRESH_LO) { - spin_lock_irqsave(&gsm->tx_lock, flags); - gsm_dlci_data_sweep(gsm); - spin_unlock_irqrestore(&gsm->tx_lock, flags); - } -} - -/** - * gsmld_read - read function for tty - * @tty: tty device - * @file: file object - * @buf: userspace buffer pointer - * @nr: size of I/O - * - * Perform reads for the line discipline. We are guaranteed that the - * line discipline will not be closed under us but we may get multiple - * parallel readers and must handle this ourselves. We may also get - * a hangup. Always called in user context, may sleep. - * - * This code must be sure never to sleep through a hangup. - */ - -static ssize_t gsmld_read(struct tty_struct *tty, struct file *file, - unsigned char __user *buf, size_t nr) -{ - return -EOPNOTSUPP; -} - -/** - * gsmld_write - write function for tty - * @tty: tty device - * @file: file object - * @buf: userspace buffer pointer - * @nr: size of I/O - * - * Called when the owner of the device wants to send a frame - * itself (or some other control data). The data is transferred - * as-is and must be properly framed and checksummed as appropriate - * by userspace. Frames are either sent whole or not at all as this - * avoids pain user side. - */ - -static ssize_t gsmld_write(struct tty_struct *tty, struct file *file, - const unsigned char *buf, size_t nr) -{ - int space = tty_write_room(tty); - if (space >= nr) - return tty->ops->write(tty, buf, nr); - set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); - return -ENOBUFS; -} - -/** - * gsmld_poll - poll method for N_GSM0710 - * @tty: terminal device - * @file: file accessing it - * @wait: poll table - * - * Called when the line discipline is asked to poll() for data or - * for special events. This code is not serialized with respect to - * other events save open/close. - * - * This code must be sure never to sleep through a hangup. - * Called without the kernel lock held - fine - */ - -static unsigned int gsmld_poll(struct tty_struct *tty, struct file *file, - poll_table *wait) -{ - unsigned int mask = 0; - struct gsm_mux *gsm = tty->disc_data; - - poll_wait(file, &tty->read_wait, wait); - poll_wait(file, &tty->write_wait, wait); - if (tty_hung_up_p(file)) - mask |= POLLHUP; - if (!tty_is_writelocked(tty) && tty_write_room(tty) > 0) - mask |= POLLOUT | POLLWRNORM; - if (gsm->dead) - mask |= POLLHUP; - return mask; -} - -static int gsmld_config(struct tty_struct *tty, struct gsm_mux *gsm, - struct gsm_config *c) -{ - int need_close = 0; - int need_restart = 0; - - /* Stuff we don't support yet - UI or I frame transport, windowing */ - if ((c->adaption !=1 && c->adaption != 2) || c->k) - return -EOPNOTSUPP; - /* Check the MRU/MTU range looks sane */ - if (c->mru > MAX_MRU || c->mtu > MAX_MTU || c->mru < 8 || c->mtu < 8) - return -EINVAL; - if (c->n2 < 3) - return -EINVAL; - if (c->encapsulation > 1) /* Basic, advanced, no I */ - return -EINVAL; - if (c->initiator > 1) - return -EINVAL; - if (c->i == 0 || c->i > 2) /* UIH and UI only */ - return -EINVAL; - /* - * See what is needed for reconfiguration - */ - - /* Timing fields */ - if (c->t1 != 0 && c->t1 != gsm->t1) - need_restart = 1; - if (c->t2 != 0 && c->t2 != gsm->t2) - need_restart = 1; - if (c->encapsulation != gsm->encoding) - need_restart = 1; - if (c->adaption != gsm->adaption) - need_restart = 1; - /* Requires care */ - if (c->initiator != gsm->initiator) - need_close = 1; - if (c->mru != gsm->mru) - need_restart = 1; - if (c->mtu != gsm->mtu) - need_restart = 1; - - /* - * Close down what is needed, restart and initiate the new - * configuration - */ - - if (need_close || need_restart) { - gsm_dlci_begin_close(gsm->dlci[0]); - /* This will timeout if the link is down due to N2 expiring */ - wait_event_interruptible(gsm->event, - gsm->dlci[0]->state == DLCI_CLOSED); - if (signal_pending(current)) - return -EINTR; - } - if (need_restart) - gsm_cleanup_mux(gsm); - - gsm->initiator = c->initiator; - gsm->mru = c->mru; - gsm->encoding = c->encapsulation; - gsm->adaption = c->adaption; - - if (c->i == 1) - gsm->ftype = UIH; - else if (c->i == 2) - gsm->ftype = UI; - - if (c->t1) - gsm->t1 = c->t1; - if (c->t2) - gsm->t2 = c->t2; - - /* FIXME: We need to separate activation/deactivation from adding - and removing from the mux array */ - if (need_restart) - gsm_activate_mux(gsm); - if (gsm->initiator && need_close) - gsm_dlci_begin_open(gsm->dlci[0]); - return 0; -} - -static int gsmld_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - struct gsm_config c; - struct gsm_mux *gsm = tty->disc_data; - - switch (cmd) { - case GSMIOC_GETCONF: - memset(&c, 0, sizeof(c)); - c.adaption = gsm->adaption; - c.encapsulation = gsm->encoding; - c.initiator = gsm->initiator; - c.t1 = gsm->t1; - c.t2 = gsm->t2; - c.t3 = 0; /* Not supported */ - c.n2 = gsm->n2; - if (gsm->ftype == UIH) - c.i = 1; - else - c.i = 2; - printk("Ftype %d i %d\n", gsm->ftype, c.i); - c.mru = gsm->mru; - c.mtu = gsm->mtu; - c.k = 0; - if (copy_to_user((void *)arg, &c, sizeof(c))) - return -EFAULT; - return 0; - case GSMIOC_SETCONF: - if (copy_from_user(&c, (void *)arg, sizeof(c))) - return -EFAULT; - return gsmld_config(tty, gsm, &c); - default: - return n_tty_ioctl_helper(tty, file, cmd, arg); - } -} - - -/* Line discipline for real tty */ -struct tty_ldisc_ops tty_ldisc_packet = { - .owner = THIS_MODULE, - .magic = TTY_LDISC_MAGIC, - .name = "n_gsm", - .open = gsmld_open, - .close = gsmld_close, - .flush_buffer = gsmld_flush_buffer, - .chars_in_buffer = gsmld_chars_in_buffer, - .read = gsmld_read, - .write = gsmld_write, - .ioctl = gsmld_ioctl, - .poll = gsmld_poll, - .receive_buf = gsmld_receive_buf, - .write_wakeup = gsmld_write_wakeup -}; - -/* - * Virtual tty side - */ - -#define TX_SIZE 512 - -static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk) -{ - u8 modembits[5]; - struct gsm_control *ctrl; - int len = 2; - - if (brk) - len++; - - modembits[0] = len << 1 | EA; /* Data bytes */ - modembits[1] = dlci->addr << 2 | 3; /* DLCI, EA, 1 */ - modembits[2] = gsm_encode_modem(dlci) << 1 | EA; - if (brk) - modembits[3] = brk << 4 | 2 | EA; /* Valid, EA */ - ctrl = gsm_control_send(dlci->gsm, CMD_MSC, modembits, len + 1); - if (ctrl == NULL) - return -ENOMEM; - return gsm_control_wait(dlci->gsm, ctrl); -} - -static int gsm_carrier_raised(struct tty_port *port) -{ - struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); - /* Not yet open so no carrier info */ - if (dlci->state != DLCI_OPEN) - return 0; - if (debug & 2) - return 1; - return dlci->modem_rx & TIOCM_CD; -} - -static void gsm_dtr_rts(struct tty_port *port, int onoff) -{ - struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port); - unsigned int modem_tx = dlci->modem_tx; - if (onoff) - modem_tx |= TIOCM_DTR | TIOCM_RTS; - else - modem_tx &= ~(TIOCM_DTR | TIOCM_RTS); - if (modem_tx != dlci->modem_tx) { - dlci->modem_tx = modem_tx; - gsmtty_modem_update(dlci, 0); - } -} - -static const struct tty_port_operations gsm_port_ops = { - .carrier_raised = gsm_carrier_raised, - .dtr_rts = gsm_dtr_rts, -}; - - -static int gsmtty_open(struct tty_struct *tty, struct file *filp) -{ - struct gsm_mux *gsm; - struct gsm_dlci *dlci; - struct tty_port *port; - unsigned int line = tty->index; - unsigned int mux = line >> 6; - - line = line & 0x3F; - - if (mux >= MAX_MUX) - return -ENXIO; - /* FIXME: we need to lock gsm_mux for lifetimes of ttys eventually */ - if (gsm_mux[mux] == NULL) - return -EUNATCH; - if (line == 0 || line > 61) /* 62/63 reserved */ - return -ECHRNG; - gsm = gsm_mux[mux]; - if (gsm->dead) - return -EL2HLT; - dlci = gsm->dlci[line]; - if (dlci == NULL) - dlci = gsm_dlci_alloc(gsm, line); - if (dlci == NULL) - return -ENOMEM; - port = &dlci->port; - port->count++; - tty->driver_data = dlci; - tty_port_tty_set(port, tty); - - dlci->modem_rx = 0; - /* We could in theory open and close before we wait - eg if we get - a DM straight back. This is ok as that will have caused a hangup */ - set_bit(ASYNCB_INITIALIZED, &port->flags); - /* Start sending off SABM messages */ - gsm_dlci_begin_open(dlci); - /* And wait for virtual carrier */ - return tty_port_block_til_ready(port, tty, filp); -} - -static void gsmtty_close(struct tty_struct *tty, struct file *filp) -{ - struct gsm_dlci *dlci = tty->driver_data; - if (dlci == NULL) - return; - if (tty_port_close_start(&dlci->port, tty, filp) == 0) - return; - gsm_dlci_begin_close(dlci); - tty_port_close_end(&dlci->port, tty); - tty_port_tty_set(&dlci->port, NULL); -} - -static void gsmtty_hangup(struct tty_struct *tty) -{ - struct gsm_dlci *dlci = tty->driver_data; - tty_port_hangup(&dlci->port); - gsm_dlci_begin_close(dlci); -} - -static int gsmtty_write(struct tty_struct *tty, const unsigned char *buf, - int len) -{ - struct gsm_dlci *dlci = tty->driver_data; - /* Stuff the bytes into the fifo queue */ - int sent = kfifo_in_locked(dlci->fifo, buf, len, &dlci->lock); - /* Need to kick the channel */ - gsm_dlci_data_kick(dlci); - return sent; -} - -static int gsmtty_write_room(struct tty_struct *tty) -{ - struct gsm_dlci *dlci = tty->driver_data; - return TX_SIZE - kfifo_len(dlci->fifo); -} - -static int gsmtty_chars_in_buffer(struct tty_struct *tty) -{ - struct gsm_dlci *dlci = tty->driver_data; - return kfifo_len(dlci->fifo); -} - -static void gsmtty_flush_buffer(struct tty_struct *tty) -{ - struct gsm_dlci *dlci = tty->driver_data; - /* Caution needed: If we implement reliable transport classes - then the data being transmitted can't simply be junked once - it has first hit the stack. Until then we can just blow it - away */ - kfifo_reset(dlci->fifo); - /* Need to unhook this DLCI from the transmit queue logic */ -} - -static void gsmtty_wait_until_sent(struct tty_struct *tty, int timeout) -{ - /* The FIFO handles the queue so the kernel will do the right - thing waiting on chars_in_buffer before calling us. No work - to do here */ -} - -static int gsmtty_tiocmget(struct tty_struct *tty, struct file *filp) -{ - struct gsm_dlci *dlci = tty->driver_data; - return dlci->modem_rx; -} - -static int gsmtty_tiocmset(struct tty_struct *tty, struct file *filp, - unsigned int set, unsigned int clear) -{ - struct gsm_dlci *dlci = tty->driver_data; - unsigned int modem_tx = dlci->modem_tx; - - modem_tx &= clear; - modem_tx |= set; - - if (modem_tx != dlci->modem_tx) { - dlci->modem_tx = modem_tx; - return gsmtty_modem_update(dlci, 0); - } - return 0; -} - - -static int gsmtty_ioctl(struct tty_struct *tty, struct file *filp, - unsigned int cmd, unsigned long arg) -{ - return -ENOIOCTLCMD; -} - -static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old) -{ - /* For the moment its fixed. In actual fact the speed information - for the virtual channel can be propogated in both directions by - the RPN control message. This however rapidly gets nasty as we - then have to remap modem signals each way according to whether - our virtual cable is null modem etc .. */ - tty_termios_copy_hw(tty->termios, old); -} - -static void gsmtty_throttle(struct tty_struct *tty) -{ - struct gsm_dlci *dlci = tty->driver_data; - if (tty->termios->c_cflag & CRTSCTS) - dlci->modem_tx &= ~TIOCM_DTR; - dlci->throttled = 1; - /* Send an MSC with DTR cleared */ - gsmtty_modem_update(dlci, 0); -} - -static void gsmtty_unthrottle(struct tty_struct *tty) -{ - struct gsm_dlci *dlci = tty->driver_data; - if (tty->termios->c_cflag & CRTSCTS) - dlci->modem_tx |= TIOCM_DTR; - dlci->throttled = 0; - /* Send an MSC with DTR set */ - gsmtty_modem_update(dlci, 0); -} - -static int gsmtty_break_ctl(struct tty_struct *tty, int state) -{ - struct gsm_dlci *dlci = tty->driver_data; - int encode = 0; /* Off */ - - if (state == -1) /* "On indefinitely" - we can't encode this - properly */ - encode = 0x0F; - else if (state > 0) { - encode = state / 200; /* mS to encoding */ - if (encode > 0x0F) - encode = 0x0F; /* Best effort */ - } - return gsmtty_modem_update(dlci, encode); -} - -static struct tty_driver *gsm_tty_driver; - -/* Virtual ttys for the demux */ -static const struct tty_operations gsmtty_ops = { - .open = gsmtty_open, - .close = gsmtty_close, - .write = gsmtty_write, - .write_room = gsmtty_write_room, - .chars_in_buffer = gsmtty_chars_in_buffer, - .flush_buffer = gsmtty_flush_buffer, - .ioctl = gsmtty_ioctl, - .throttle = gsmtty_throttle, - .unthrottle = gsmtty_unthrottle, - .set_termios = gsmtty_set_termios, - .hangup = gsmtty_hangup, - .wait_until_sent = gsmtty_wait_until_sent, - .tiocmget = gsmtty_tiocmget, - .tiocmset = gsmtty_tiocmset, - .break_ctl = gsmtty_break_ctl, -}; - - - -static int __init gsm_init(void) -{ - /* Fill in our line protocol discipline, and register it */ - int status = tty_register_ldisc(N_GSM0710, &tty_ldisc_packet); - if (status != 0) { - printk(KERN_ERR "n_gsm: can't register line discipline (err = %d)\n", status); - return status; - } - - gsm_tty_driver = alloc_tty_driver(256); - if (!gsm_tty_driver) { - tty_unregister_ldisc(N_GSM0710); - printk(KERN_ERR "gsm_init: tty allocation failed.\n"); - return -EINVAL; - } - gsm_tty_driver->owner = THIS_MODULE; - gsm_tty_driver->driver_name = "gsmtty"; - gsm_tty_driver->name = "gsmtty"; - gsm_tty_driver->major = 0; /* Dynamic */ - gsm_tty_driver->minor_start = 0; - gsm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL; - gsm_tty_driver->subtype = SERIAL_TYPE_NORMAL; - gsm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV - | TTY_DRIVER_HARDWARE_BREAK; - gsm_tty_driver->init_termios = tty_std_termios; - /* Fixme */ - gsm_tty_driver->init_termios.c_lflag &= ~ECHO; - tty_set_operations(gsm_tty_driver, &gsmtty_ops); - - spin_lock_init(&gsm_mux_lock); - - if (tty_register_driver(gsm_tty_driver)) { - put_tty_driver(gsm_tty_driver); - tty_unregister_ldisc(N_GSM0710); - printk(KERN_ERR "gsm_init: tty registration failed.\n"); - return -EBUSY; - } - printk(KERN_INFO "gsm_init: loaded as %d,%d.\n", gsm_tty_driver->major, gsm_tty_driver->minor_start); - return 0; -} - -static void __exit gsm_exit(void) -{ - int status = tty_unregister_ldisc(N_GSM0710); - if (status != 0) - printk(KERN_ERR "n_gsm: can't unregister line discipline (err = %d)\n", status); - tty_unregister_driver(gsm_tty_driver); - put_tty_driver(gsm_tty_driver); - printk(KERN_INFO "gsm_init: unloaded.\n"); -} - -module_init(gsm_init); -module_exit(gsm_exit); - - -MODULE_LICENSE("GPL"); -MODULE_ALIAS_LDISC(N_GSM0710); diff --git a/drivers/char/n_hdlc.c b/drivers/char/n_hdlc.c deleted file mode 100644 index 47d3228..0000000 --- a/drivers/char/n_hdlc.c +++ /dev/null @@ -1,1007 +0,0 @@ -/* generic HDLC line discipline for Linux - * - * Written by Paul Fulghum paulkf@microgate.com - * for Microgate Corporation - * - * Microgate and SyncLink are registered trademarks of Microgate Corporation - * - * Adapted from ppp.c, written by Michael Callahan <callahan@maths.ox.ac.uk>, - * Al Longyear <longyear@netcom.com>, - * Paul Mackerras <Paul.Mackerras@cs.anu.edu.au> - * - * Original release 01/11/99 - * - * This code is released under the GNU General Public License (GPL) - * - * This module implements the tty line discipline N_HDLC for use with - * tty device drivers that support bit-synchronous HDLC communications. - * - * All HDLC data is frame oriented which means: - * - * 1. tty write calls represent one complete transmit frame of data - * The device driver should accept the complete frame or none of - * the frame (busy) in the write method. Each write call should have - * a byte count in the range of 2-65535 bytes (2 is min HDLC frame - * with 1 addr byte and 1 ctrl byte). The max byte count of 65535 - * should include any crc bytes required. For example, when using - * CCITT CRC32, 4 crc bytes are required, so the maximum size frame - * the application may transmit is limited to 65531 bytes. For CCITT - * CRC16, the maximum application frame size would be 65533. - * - * - * 2. receive callbacks from the device driver represents - * one received frame. The device driver should bypass - * the tty flip buffer and call the line discipline receive - * callback directly to avoid fragmenting or concatenating - * multiple frames into a single receive callback. - * - * The HDLC line discipline queues the receive frames in separate - * buffers so complete receive frames can be returned by the - * tty read calls. - * - * 3. tty read calls returns an entire frame of data or nothing. - * - * 4. all send and receive data is considered raw. No processing - * or translation is performed by the line discipline, regardless - * of the tty flags - * - * 5. When line discipline is queried for the amount of receive - * data available (FIOC), 0 is returned if no data available, - * otherwise the count of the next available frame is returned. - * (instead of the sum of all received frame counts). - * - * These conventions allow the standard tty programming interface - * to be used for synchronous HDLC applications when used with - * this line discipline (or another line discipline that is frame - * oriented such as N_PPP). - * - * The SyncLink driver (synclink.c) implements both asynchronous - * (using standard line discipline N_TTY) and synchronous HDLC - * (using N_HDLC) communications, with the latter using the above - * conventions. - * - * This implementation is very basic and does not maintain - * any statistics. The main point is to enforce the raw data - * and frame orientation of HDLC communications. - * - * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED - * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE - * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, - * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES - * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR - * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, - * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) - * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED - * OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -#define HDLC_MAGIC 0x239e - -#include <linux/module.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/types.h> -#include <linux/fcntl.h> -#include <linux/interrupt.h> -#include <linux/ptrace.h> - -#undef VERSION -#define VERSION(major,minor,patch) (((((major)<<8)+(minor))<<8)+(patch)) - -#include <linux/poll.h> -#include <linux/in.h> -#include <linux/ioctl.h> -#include <linux/slab.h> -#include <linux/tty.h> -#include <linux/errno.h> -#include <linux/smp_lock.h> -#include <linux/string.h> /* used in new tty drivers */ -#include <linux/signal.h> /* used in new tty drivers */ -#include <linux/if.h> -#include <linux/bitops.h> - -#include <asm/system.h> -#include <asm/termios.h> -#include <asm/uaccess.h> - -/* - * Buffers for individual HDLC frames - */ -#define MAX_HDLC_FRAME_SIZE 65535 -#define DEFAULT_RX_BUF_COUNT 10 -#define MAX_RX_BUF_COUNT 60 -#define DEFAULT_TX_BUF_COUNT 3 - -struct n_hdlc_buf { - struct n_hdlc_buf *link; - int count; - char buf[1]; -}; - -#define N_HDLC_BUF_SIZE (sizeof(struct n_hdlc_buf) + maxframe) - -struct n_hdlc_buf_list { - struct n_hdlc_buf *head; - struct n_hdlc_buf *tail; - int count; - spinlock_t spinlock; -}; - -/** - * struct n_hdlc - per device instance data structure - * @magic - magic value for structure - * @flags - miscellaneous control flags - * @tty - ptr to TTY structure - * @backup_tty - TTY to use if tty gets closed - * @tbusy - reentrancy flag for tx wakeup code - * @woke_up - FIXME: describe this field - * @tbuf - currently transmitting tx buffer - * @tx_buf_list - list of pending transmit frame buffers - * @rx_buf_list - list of received frame buffers - * @tx_free_buf_list - list unused transmit frame buffers - * @rx_free_buf_list - list unused received frame buffers - */ -struct n_hdlc { - int magic; - __u32 flags; - struct tty_struct *tty; - struct tty_struct *backup_tty; - int tbusy; - int woke_up; - struct n_hdlc_buf *tbuf; - struct n_hdlc_buf_list tx_buf_list; - struct n_hdlc_buf_list rx_buf_list; - struct n_hdlc_buf_list tx_free_buf_list; - struct n_hdlc_buf_list rx_free_buf_list; -}; - -/* - * HDLC buffer list manipulation functions - */ -static void n_hdlc_buf_list_init(struct n_hdlc_buf_list *list); -static void n_hdlc_buf_put(struct n_hdlc_buf_list *list, - struct n_hdlc_buf *buf); -static struct n_hdlc_buf *n_hdlc_buf_get(struct n_hdlc_buf_list *list); - -/* Local functions */ - -static struct n_hdlc *n_hdlc_alloc (void); - -/* debug level can be set by insmod for debugging purposes */ -#define DEBUG_LEVEL_INFO 1 -static int debuglevel; - -/* max frame size for memory allocations */ -static int maxframe = 4096; - -/* TTY callbacks */ - -static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file, - __u8 __user *buf, size_t nr); -static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file, - const unsigned char *buf, size_t nr); -static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg); -static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp, - poll_table *wait); -static int n_hdlc_tty_open(struct tty_struct *tty); -static void n_hdlc_tty_close(struct tty_struct *tty); -static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *cp, - char *fp, int count); -static void n_hdlc_tty_wakeup(struct tty_struct *tty); - -#define bset(p,b) ((p)[(b) >> 5] |= (1 << ((b) & 0x1f))) - -#define tty2n_hdlc(tty) ((struct n_hdlc *) ((tty)->disc_data)) -#define n_hdlc2tty(n_hdlc) ((n_hdlc)->tty) - -static void flush_rx_queue(struct tty_struct *tty) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc(tty); - struct n_hdlc_buf *buf; - - while ((buf = n_hdlc_buf_get(&n_hdlc->rx_buf_list))) - n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, buf); -} - -static void flush_tx_queue(struct tty_struct *tty) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc(tty); - struct n_hdlc_buf *buf; - unsigned long flags; - - while ((buf = n_hdlc_buf_get(&n_hdlc->tx_buf_list))) - n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, buf); - spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock, flags); - if (n_hdlc->tbuf) { - n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, n_hdlc->tbuf); - n_hdlc->tbuf = NULL; - } - spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags); -} - -static struct tty_ldisc_ops n_hdlc_ldisc = { - .owner = THIS_MODULE, - .magic = TTY_LDISC_MAGIC, - .name = "hdlc", - .open = n_hdlc_tty_open, - .close = n_hdlc_tty_close, - .read = n_hdlc_tty_read, - .write = n_hdlc_tty_write, - .ioctl = n_hdlc_tty_ioctl, - .poll = n_hdlc_tty_poll, - .receive_buf = n_hdlc_tty_receive, - .write_wakeup = n_hdlc_tty_wakeup, - .flush_buffer = flush_rx_queue, -}; - -/** - * n_hdlc_release - release an n_hdlc per device line discipline info structure - * @n_hdlc - per device line discipline info structure - */ -static void n_hdlc_release(struct n_hdlc *n_hdlc) -{ - struct tty_struct *tty = n_hdlc2tty (n_hdlc); - struct n_hdlc_buf *buf; - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_release() called\n",__FILE__,__LINE__); - - /* Ensure that the n_hdlcd process is not hanging on select()/poll() */ - wake_up_interruptible (&tty->read_wait); - wake_up_interruptible (&tty->write_wait); - - if (tty->disc_data == n_hdlc) - tty->disc_data = NULL; /* Break the tty->n_hdlc link */ - - /* Release transmit and receive buffers */ - for(;;) { - buf = n_hdlc_buf_get(&n_hdlc->rx_free_buf_list); - if (buf) { - kfree(buf); - } else - break; - } - for(;;) { - buf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list); - if (buf) { - kfree(buf); - } else - break; - } - for(;;) { - buf = n_hdlc_buf_get(&n_hdlc->rx_buf_list); - if (buf) { - kfree(buf); - } else - break; - } - for(;;) { - buf = n_hdlc_buf_get(&n_hdlc->tx_buf_list); - if (buf) { - kfree(buf); - } else - break; - } - kfree(n_hdlc->tbuf); - kfree(n_hdlc); - -} /* end of n_hdlc_release() */ - -/** - * n_hdlc_tty_close - line discipline close - * @tty - pointer to tty info structure - * - * Called when the line discipline is changed to something - * else, the tty is closed, or the tty detects a hangup. - */ -static void n_hdlc_tty_close(struct tty_struct *tty) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc (tty); - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_close() called\n",__FILE__,__LINE__); - - if (n_hdlc != NULL) { - if (n_hdlc->magic != HDLC_MAGIC) { - printk (KERN_WARNING"n_hdlc: trying to close unopened tty!\n"); - return; - } -#if defined(TTY_NO_WRITE_SPLIT) - clear_bit(TTY_NO_WRITE_SPLIT,&tty->flags); -#endif - tty->disc_data = NULL; - if (tty == n_hdlc->backup_tty) - n_hdlc->backup_tty = NULL; - if (tty != n_hdlc->tty) - return; - if (n_hdlc->backup_tty) { - n_hdlc->tty = n_hdlc->backup_tty; - } else { - n_hdlc_release (n_hdlc); - } - } - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_close() success\n",__FILE__,__LINE__); - -} /* end of n_hdlc_tty_close() */ - -/** - * n_hdlc_tty_open - called when line discipline changed to n_hdlc - * @tty - pointer to tty info structure - * - * Returns 0 if success, otherwise error code - */ -static int n_hdlc_tty_open (struct tty_struct *tty) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc (tty); - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_open() called (device=%s)\n", - __FILE__,__LINE__, - tty->name); - - /* There should not be an existing table for this slot. */ - if (n_hdlc) { - printk (KERN_ERR"n_hdlc_tty_open:tty already associated!\n" ); - return -EEXIST; - } - - n_hdlc = n_hdlc_alloc(); - if (!n_hdlc) { - printk (KERN_ERR "n_hdlc_alloc failed\n"); - return -ENFILE; - } - - tty->disc_data = n_hdlc; - n_hdlc->tty = tty; - tty->receive_room = 65536; - -#if defined(TTY_NO_WRITE_SPLIT) - /* change tty_io write() to not split large writes into 8K chunks */ - set_bit(TTY_NO_WRITE_SPLIT,&tty->flags); -#endif - - /* flush receive data from driver */ - tty_driver_flush_buffer(tty); - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_open() success\n",__FILE__,__LINE__); - - return 0; - -} /* end of n_tty_hdlc_open() */ - -/** - * n_hdlc_send_frames - send frames on pending send buffer list - * @n_hdlc - pointer to ldisc instance data - * @tty - pointer to tty instance data - * - * Send frames on pending send buffer list until the driver does not accept a - * frame (busy) this function is called after adding a frame to the send buffer - * list and by the tty wakeup callback. - */ -static void n_hdlc_send_frames(struct n_hdlc *n_hdlc, struct tty_struct *tty) -{ - register int actual; - unsigned long flags; - struct n_hdlc_buf *tbuf; - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_send_frames() called\n",__FILE__,__LINE__); - check_again: - - spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock, flags); - if (n_hdlc->tbusy) { - n_hdlc->woke_up = 1; - spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags); - return; - } - n_hdlc->tbusy = 1; - n_hdlc->woke_up = 0; - spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags); - - /* get current transmit buffer or get new transmit */ - /* buffer from list of pending transmit buffers */ - - tbuf = n_hdlc->tbuf; - if (!tbuf) - tbuf = n_hdlc_buf_get(&n_hdlc->tx_buf_list); - - while (tbuf) { - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)sending frame %p, count=%d\n", - __FILE__,__LINE__,tbuf,tbuf->count); - - /* Send the next block of data to device */ - tty->flags |= (1 << TTY_DO_WRITE_WAKEUP); - actual = tty->ops->write(tty, tbuf->buf, tbuf->count); - - /* rollback was possible and has been done */ - if (actual == -ERESTARTSYS) { - n_hdlc->tbuf = tbuf; - break; - } - /* if transmit error, throw frame away by */ - /* pretending it was accepted by driver */ - if (actual < 0) - actual = tbuf->count; - - if (actual == tbuf->count) { - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)frame %p completed\n", - __FILE__,__LINE__,tbuf); - - /* free current transmit buffer */ - n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, tbuf); - - /* this tx buffer is done */ - n_hdlc->tbuf = NULL; - - /* wait up sleeping writers */ - wake_up_interruptible(&tty->write_wait); - - /* get next pending transmit buffer */ - tbuf = n_hdlc_buf_get(&n_hdlc->tx_buf_list); - } else { - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)frame %p pending\n", - __FILE__,__LINE__,tbuf); - - /* buffer not accepted by driver */ - /* set this buffer as pending buffer */ - n_hdlc->tbuf = tbuf; - break; - } - } - - if (!tbuf) - tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); - - /* Clear the re-entry flag */ - spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock, flags); - n_hdlc->tbusy = 0; - spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags); - - if (n_hdlc->woke_up) - goto check_again; - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_send_frames() exit\n",__FILE__,__LINE__); - -} /* end of n_hdlc_send_frames() */ - -/** - * n_hdlc_tty_wakeup - Callback for transmit wakeup - * @tty - pointer to associated tty instance data - * - * Called when low level device driver can accept more send data. - */ -static void n_hdlc_tty_wakeup(struct tty_struct *tty) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc(tty); - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_wakeup() called\n",__FILE__,__LINE__); - - if (!n_hdlc) - return; - - if (tty != n_hdlc->tty) { - tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); - return; - } - - n_hdlc_send_frames (n_hdlc, tty); - -} /* end of n_hdlc_tty_wakeup() */ - -/** - * n_hdlc_tty_receive - Called by tty driver when receive data is available - * @tty - pointer to tty instance data - * @data - pointer to received data - * @flags - pointer to flags for data - * @count - count of received data in bytes - * - * Called by tty low level driver when receive data is available. Data is - * interpreted as one HDLC frame. - */ -static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, - char *flags, int count) -{ - register struct n_hdlc *n_hdlc = tty2n_hdlc (tty); - register struct n_hdlc_buf *buf; - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_receive() called count=%d\n", - __FILE__,__LINE__, count); - - /* This can happen if stuff comes in on the backup tty */ - if (!n_hdlc || tty != n_hdlc->tty) - return; - - /* verify line is using HDLC discipline */ - if (n_hdlc->magic != HDLC_MAGIC) { - printk("%s(%d) line not using HDLC discipline\n", - __FILE__,__LINE__); - return; - } - - if ( count>maxframe ) { - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d) rx count>maxframesize, data discarded\n", - __FILE__,__LINE__); - return; - } - - /* get a free HDLC buffer */ - buf = n_hdlc_buf_get(&n_hdlc->rx_free_buf_list); - if (!buf) { - /* no buffers in free list, attempt to allocate another rx buffer */ - /* unless the maximum count has been reached */ - if (n_hdlc->rx_buf_list.count < MAX_RX_BUF_COUNT) - buf = kmalloc(N_HDLC_BUF_SIZE, GFP_ATOMIC); - } - - if (!buf) { - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d) no more rx buffers, data discarded\n", - __FILE__,__LINE__); - return; - } - - /* copy received data to HDLC buffer */ - memcpy(buf->buf,data,count); - buf->count=count; - - /* add HDLC buffer to list of received frames */ - n_hdlc_buf_put(&n_hdlc->rx_buf_list, buf); - - /* wake up any blocked reads and perform async signalling */ - wake_up_interruptible (&tty->read_wait); - if (n_hdlc->tty->fasync != NULL) - kill_fasync (&n_hdlc->tty->fasync, SIGIO, POLL_IN); - -} /* end of n_hdlc_tty_receive() */ - -/** - * n_hdlc_tty_read - Called to retrieve one frame of data (if available) - * @tty - pointer to tty instance data - * @file - pointer to open file object - * @buf - pointer to returned data buffer - * @nr - size of returned data buffer - * - * Returns the number of bytes returned or error code. - */ -static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file, - __u8 __user *buf, size_t nr) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc(tty); - int ret; - struct n_hdlc_buf *rbuf; - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_read() called\n",__FILE__,__LINE__); - - /* Validate the pointers */ - if (!n_hdlc) - return -EIO; - - /* verify user access to buffer */ - if (!access_ok(VERIFY_WRITE, buf, nr)) { - printk(KERN_WARNING "%s(%d) n_hdlc_tty_read() can't verify user " - "buffer\n", __FILE__, __LINE__); - return -EFAULT; - } - - tty_lock(); - - for (;;) { - if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) { - tty_unlock(); - return -EIO; - } - - n_hdlc = tty2n_hdlc (tty); - if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC || - tty != n_hdlc->tty) { - tty_unlock(); - return 0; - } - - rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list); - if (rbuf) - break; - - /* no data */ - if (file->f_flags & O_NONBLOCK) { - tty_unlock(); - return -EAGAIN; - } - - interruptible_sleep_on (&tty->read_wait); - if (signal_pending(current)) { - tty_unlock(); - return -EINTR; - } - } - - if (rbuf->count > nr) - /* frame too large for caller's buffer (discard frame) */ - ret = -EOVERFLOW; - else { - /* Copy the data to the caller's buffer */ - if (copy_to_user(buf, rbuf->buf, rbuf->count)) - ret = -EFAULT; - else - ret = rbuf->count; - } - - /* return HDLC buffer to free list unless the free list */ - /* count has exceeded the default value, in which case the */ - /* buffer is freed back to the OS to conserve memory */ - if (n_hdlc->rx_free_buf_list.count > DEFAULT_RX_BUF_COUNT) - kfree(rbuf); - else - n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,rbuf); - tty_unlock(); - return ret; - -} /* end of n_hdlc_tty_read() */ - -/** - * n_hdlc_tty_write - write a single frame of data to device - * @tty - pointer to associated tty device instance data - * @file - pointer to file object data - * @data - pointer to transmit data (one frame) - * @count - size of transmit frame in bytes - * - * Returns the number of bytes written (or error code). - */ -static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file, - const unsigned char *data, size_t count) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc (tty); - int error = 0; - DECLARE_WAITQUEUE(wait, current); - struct n_hdlc_buf *tbuf; - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_write() called count=%Zd\n", - __FILE__,__LINE__,count); - - /* Verify pointers */ - if (!n_hdlc) - return -EIO; - - if (n_hdlc->magic != HDLC_MAGIC) - return -EIO; - - /* verify frame size */ - if (count > maxframe ) { - if (debuglevel & DEBUG_LEVEL_INFO) - printk (KERN_WARNING - "n_hdlc_tty_write: truncating user packet " - "from %lu to %d\n", (unsigned long) count, - maxframe ); - count = maxframe; - } - - tty_lock(); - - add_wait_queue(&tty->write_wait, &wait); - set_current_state(TASK_INTERRUPTIBLE); - - /* Allocate transmit buffer */ - /* sleep until transmit buffer available */ - while (!(tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list))) { - if (file->f_flags & O_NONBLOCK) { - error = -EAGAIN; - break; - } - schedule(); - - n_hdlc = tty2n_hdlc (tty); - if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC || - tty != n_hdlc->tty) { - printk("n_hdlc_tty_write: %p invalid after wait!\n", n_hdlc); - error = -EIO; - break; - } - - if (signal_pending(current)) { - error = -EINTR; - break; - } - } - - set_current_state(TASK_RUNNING); - remove_wait_queue(&tty->write_wait, &wait); - - if (!error) { - /* Retrieve the user's buffer */ - memcpy(tbuf->buf, data, count); - - /* Send the data */ - tbuf->count = error = count; - n_hdlc_buf_put(&n_hdlc->tx_buf_list,tbuf); - n_hdlc_send_frames(n_hdlc,tty); - } - tty_unlock(); - return error; - -} /* end of n_hdlc_tty_write() */ - -/** - * n_hdlc_tty_ioctl - process IOCTL system call for the tty device. - * @tty - pointer to tty instance data - * @file - pointer to open file object for device - * @cmd - IOCTL command code - * @arg - argument for IOCTL call (cmd dependent) - * - * Returns command dependent result. - */ -static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc (tty); - int error = 0; - int count; - unsigned long flags; - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_ioctl() called %d\n", - __FILE__,__LINE__,cmd); - - /* Verify the status of the device */ - if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC) - return -EBADF; - - switch (cmd) { - case FIONREAD: - /* report count of read data available */ - /* in next available frame (if any) */ - spin_lock_irqsave(&n_hdlc->rx_buf_list.spinlock,flags); - if (n_hdlc->rx_buf_list.head) - count = n_hdlc->rx_buf_list.head->count; - else - count = 0; - spin_unlock_irqrestore(&n_hdlc->rx_buf_list.spinlock,flags); - error = put_user(count, (int __user *)arg); - break; - - case TIOCOUTQ: - /* get the pending tx byte count in the driver */ - count = tty_chars_in_buffer(tty); - /* add size of next output frame in queue */ - spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock,flags); - if (n_hdlc->tx_buf_list.head) - count += n_hdlc->tx_buf_list.head->count; - spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock,flags); - error = put_user(count, (int __user *)arg); - break; - - case TCFLSH: - switch (arg) { - case TCIOFLUSH: - case TCOFLUSH: - flush_tx_queue(tty); - } - /* fall through to default */ - - default: - error = n_tty_ioctl_helper(tty, file, cmd, arg); - break; - } - return error; - -} /* end of n_hdlc_tty_ioctl() */ - -/** - * n_hdlc_tty_poll - TTY callback for poll system call - * @tty - pointer to tty instance data - * @filp - pointer to open file object for device - * @poll_table - wait queue for operations - * - * Determine which operations (read/write) will not block and return info - * to caller. - * Returns a bit mask containing info on which ops will not block. - */ -static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp, - poll_table *wait) -{ - struct n_hdlc *n_hdlc = tty2n_hdlc (tty); - unsigned int mask = 0; - - if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_tty_poll() called\n",__FILE__,__LINE__); - - if (n_hdlc && n_hdlc->magic == HDLC_MAGIC && tty == n_hdlc->tty) { - /* queue current process into any wait queue that */ - /* may awaken in the future (read and write) */ - - poll_wait(filp, &tty->read_wait, wait); - poll_wait(filp, &tty->write_wait, wait); - - /* set bits for operations that won't block */ - if (n_hdlc->rx_buf_list.head) - mask |= POLLIN | POLLRDNORM; /* readable */ - if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) - mask |= POLLHUP; - if (tty_hung_up_p(filp)) - mask |= POLLHUP; - if (!tty_is_writelocked(tty) && - n_hdlc->tx_free_buf_list.head) - mask |= POLLOUT | POLLWRNORM; /* writable */ - } - return mask; -} /* end of n_hdlc_tty_poll() */ - -/** - * n_hdlc_alloc - allocate an n_hdlc instance data structure - * - * Returns a pointer to newly created structure if success, otherwise %NULL - */ -static struct n_hdlc *n_hdlc_alloc(void) -{ - struct n_hdlc_buf *buf; - int i; - struct n_hdlc *n_hdlc = kmalloc(sizeof(*n_hdlc), GFP_KERNEL); - - if (!n_hdlc) - return NULL; - - memset(n_hdlc, 0, sizeof(*n_hdlc)); - - n_hdlc_buf_list_init(&n_hdlc->rx_free_buf_list); - n_hdlc_buf_list_init(&n_hdlc->tx_free_buf_list); - n_hdlc_buf_list_init(&n_hdlc->rx_buf_list); - n_hdlc_buf_list_init(&n_hdlc->tx_buf_list); - - /* allocate free rx buffer list */ - for(i=0;i<DEFAULT_RX_BUF_COUNT;i++) { - buf = kmalloc(N_HDLC_BUF_SIZE, GFP_KERNEL); - if (buf) - n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,buf); - else if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_alloc(), kalloc() failed for rx buffer %d\n",__FILE__,__LINE__, i); - } - - /* allocate free tx buffer list */ - for(i=0;i<DEFAULT_TX_BUF_COUNT;i++) { - buf = kmalloc(N_HDLC_BUF_SIZE, GFP_KERNEL); - if (buf) - n_hdlc_buf_put(&n_hdlc->tx_free_buf_list,buf); - else if (debuglevel >= DEBUG_LEVEL_INFO) - printk("%s(%d)n_hdlc_alloc(), kalloc() failed for tx buffer %d\n",__FILE__,__LINE__, i); - } - - /* Initialize the control block */ - n_hdlc->magic = HDLC_MAGIC; - n_hdlc->flags = 0; - - return n_hdlc; - -} /* end of n_hdlc_alloc() */ - -/** - * n_hdlc_buf_list_init - initialize specified HDLC buffer list - * @list - pointer to buffer list - */ -static void n_hdlc_buf_list_init(struct n_hdlc_buf_list *list) -{ - memset(list, 0, sizeof(*list)); - spin_lock_init(&list->spinlock); -} /* end of n_hdlc_buf_list_init() */ - -/** - * n_hdlc_buf_put - add specified HDLC buffer to tail of specified list - * @list - pointer to buffer list - * @buf - pointer to buffer - */ -static void n_hdlc_buf_put(struct n_hdlc_buf_list *list, - struct n_hdlc_buf *buf) -{ - unsigned long flags; - spin_lock_irqsave(&list->spinlock,flags); - - buf->link=NULL; - if (list->tail) - list->tail->link = buf; - else - list->head = buf; - list->tail = buf; - (list->count)++; - - spin_unlock_irqrestore(&list->spinlock,flags); - -} /* end of n_hdlc_buf_put() */ - -/** - * n_hdlc_buf_get - remove and return an HDLC buffer from list - * @list - pointer to HDLC buffer list - * - * Remove and return an HDLC buffer from the head of the specified HDLC buffer - * list. - * Returns a pointer to HDLC buffer if available, otherwise %NULL. - */ -static struct n_hdlc_buf* n_hdlc_buf_get(struct n_hdlc_buf_list *list) -{ - unsigned long flags; - struct n_hdlc_buf *buf; - spin_lock_irqsave(&list->spinlock,flags); - - buf = list->head; - if (buf) { - list->head = buf->link; - (list->count)--; - } - if (!list->head) - list->tail = NULL; - - spin_unlock_irqrestore(&list->spinlock,flags); - return buf; - -} /* end of n_hdlc_buf_get() */ - -static char hdlc_banner[] __initdata = - KERN_INFO "HDLC line discipline maxframe=%u\n"; -static char hdlc_register_ok[] __initdata = - KERN_INFO "N_HDLC line discipline registered.\n"; -static char hdlc_register_fail[] __initdata = - KERN_ERR "error registering line discipline: %d\n"; -static char hdlc_init_fail[] __initdata = - KERN_INFO "N_HDLC: init failure %d\n"; - -static int __init n_hdlc_init(void) -{ - int status; - - /* range check maxframe arg */ - if (maxframe < 4096) - maxframe = 4096; - else if (maxframe > 65535) - maxframe = 65535; - - printk(hdlc_banner, maxframe); - - status = tty_register_ldisc(N_HDLC, &n_hdlc_ldisc); - if (!status) - printk(hdlc_register_ok); - else - printk(hdlc_register_fail, status); - - if (status) - printk(hdlc_init_fail, status); - return status; - -} /* end of init_module() */ - -static char hdlc_unregister_ok[] __exitdata = - KERN_INFO "N_HDLC: line discipline unregistered\n"; -static char hdlc_unregister_fail[] __exitdata = - KERN_ERR "N_HDLC: can't unregister line discipline (err = %d)\n"; - -static void __exit n_hdlc_exit(void) -{ - /* Release tty registration of line discipline */ - int status = tty_unregister_ldisc(N_HDLC); - - if (status) - printk(hdlc_unregister_fail, status); - else - printk(hdlc_unregister_ok); -} - -module_init(n_hdlc_init); -module_exit(n_hdlc_exit); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Paul Fulghum paulkf@microgate.com"); -module_param(debuglevel, int, 0); -module_param(maxframe, int, 0); -MODULE_ALIAS_LDISC(N_HDLC); diff --git a/drivers/char/n_r3964.c b/drivers/char/n_r3964.c deleted file mode 100644 index 88dda0c..0000000 --- a/drivers/char/n_r3964.c +++ /dev/null @@ -1,1264 +0,0 @@ -/* r3964 linediscipline for linux - * - * ----------------------------------------------------------- - * Copyright by - * Philips Automation Projects - * Kassel (Germany) - * ----------------------------------------------------------- - * This software may be used and distributed according to the terms of - * the GNU General Public License, incorporated herein by reference. - * - * Author: - * L. Haag - * - * $Log: n_r3964.c,v $ - * Revision 1.10 2001/03/18 13:02:24 dwmw2 - * Fix timer usage, use spinlocks properly. - * - * Revision 1.9 2001/03/18 12:52:14 dwmw2 - * Merge changes in 2.4.2 - * - * Revision 1.8 2000/03/23 14:14:54 dwmw2 - * Fix race in sleeping in r3964_read() - * - * Revision 1.7 1999/28/08 11:41:50 dwmw2 - * Port to 2.3 kernel - * - * Revision 1.6 1998/09/30 00:40:40 dwmw2 - * Fixed compilation on 2.0.x kernels - * Updated to newly registered tty-ldisc number 9 - * - * Revision 1.5 1998/09/04 21:57:36 dwmw2 - * Signal handling bug fixes, port to 2.1.x. - * - * Revision 1.4 1998/04/02 20:26:59 lhaag - * select, blocking, ... - * - * Revision 1.3 1998/02/12 18:58:43 root - * fixed some memory leaks - * calculation of checksum characters - * - * Revision 1.2 1998/02/07 13:03:34 root - * ioctl read_telegram - * - * Revision 1.1 1998/02/06 19:21:03 root - * Initial revision - * - * - */ - -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/types.h> -#include <linux/fcntl.h> -#include <linux/interrupt.h> -#include <linux/ptrace.h> -#include <linux/ioport.h> -#include <linux/in.h> -#include <linux/slab.h> -#include <linux/smp_lock.h> -#include <linux/tty.h> -#include <linux/errno.h> -#include <linux/string.h> /* used in new tty drivers */ -#include <linux/signal.h> /* used in new tty drivers */ -#include <linux/ioctl.h> -#include <linux/n_r3964.h> -#include <linux/poll.h> -#include <linux/init.h> -#include <asm/uaccess.h> - -/*#define DEBUG_QUEUE*/ - -/* Log successful handshake and protocol operations */ -/*#define DEBUG_PROTO_S*/ - -/* Log handshake and protocol errors: */ -/*#define DEBUG_PROTO_E*/ - -/* Log Linediscipline operations (open, close, read, write...): */ -/*#define DEBUG_LDISC*/ - -/* Log module and memory operations (init, cleanup; kmalloc, kfree): */ -/*#define DEBUG_MODUL*/ - -/* Macro helpers for debug output: */ -#define TRACE(format, args...) printk("r3964: " format "\n" , ## args) - -#ifdef DEBUG_MODUL -#define TRACE_M(format, args...) printk("r3964: " format "\n" , ## args) -#else -#define TRACE_M(fmt, arg...) do {} while (0) -#endif -#ifdef DEBUG_PROTO_S -#define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args) -#else -#define TRACE_PS(fmt, arg...) do {} while (0) -#endif -#ifdef DEBUG_PROTO_E -#define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args) -#else -#define TRACE_PE(fmt, arg...) do {} while (0) -#endif -#ifdef DEBUG_LDISC -#define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args) -#else -#define TRACE_L(fmt, arg...) do {} while (0) -#endif -#ifdef DEBUG_QUEUE -#define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args) -#else -#define TRACE_Q(fmt, arg...) do {} while (0) -#endif -static void add_tx_queue(struct r3964_info *, struct r3964_block_header *); -static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code); -static void put_char(struct r3964_info *pInfo, unsigned char ch); -static void trigger_transmit(struct r3964_info *pInfo); -static void retry_transmit(struct r3964_info *pInfo); -static void transmit_block(struct r3964_info *pInfo); -static void receive_char(struct r3964_info *pInfo, const unsigned char c); -static void receive_error(struct r3964_info *pInfo, const char flag); -static void on_timeout(unsigned long priv); -static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg); -static int read_telegram(struct r3964_info *pInfo, struct pid *pid, - unsigned char __user * buf); -static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, - int error_code, struct r3964_block_header *pBlock); -static struct r3964_message *remove_msg(struct r3964_info *pInfo, - struct r3964_client_info *pClient); -static void remove_client_block(struct r3964_info *pInfo, - struct r3964_client_info *pClient); - -static int r3964_open(struct tty_struct *tty); -static void r3964_close(struct tty_struct *tty); -static ssize_t r3964_read(struct tty_struct *tty, struct file *file, - unsigned char __user * buf, size_t nr); -static ssize_t r3964_write(struct tty_struct *tty, struct file *file, - const unsigned char *buf, size_t nr); -static int r3964_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg); -static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old); -static unsigned int r3964_poll(struct tty_struct *tty, struct file *file, - struct poll_table_struct *wait); -static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count); - -static struct tty_ldisc_ops tty_ldisc_N_R3964 = { - .owner = THIS_MODULE, - .magic = TTY_LDISC_MAGIC, - .name = "R3964", - .open = r3964_open, - .close = r3964_close, - .read = r3964_read, - .write = r3964_write, - .ioctl = r3964_ioctl, - .set_termios = r3964_set_termios, - .poll = r3964_poll, - .receive_buf = r3964_receive_buf, -}; - -static void dump_block(const unsigned char *block, unsigned int length) -{ - unsigned int i, j; - char linebuf[16 * 3 + 1]; - - for (i = 0; i < length; i += 16) { - for (j = 0; (j < 16) && (j + i < length); j++) { - sprintf(linebuf + 3 * j, "%02x ", block[i + j]); - } - linebuf[3 * j] = '\0'; - TRACE_PS("%s", linebuf); - } -} - -/************************************************************* - * Driver initialisation - *************************************************************/ - -/************************************************************* - * Module support routines - *************************************************************/ - -static void __exit r3964_exit(void) -{ - int status; - - TRACE_M("cleanup_module()"); - - status = tty_unregister_ldisc(N_R3964); - - if (status != 0) { - printk(KERN_ERR "r3964: error unregistering linediscipline: " - "%d\n", status); - } else { - TRACE_L("linediscipline successfully unregistered"); - } -} - -static int __init r3964_init(void) -{ - int status; - - printk("r3964: Philips r3964 Driver $Revision: 1.10 $\n"); - - /* - * Register the tty line discipline - */ - - status = tty_register_ldisc(N_R3964, &tty_ldisc_N_R3964); - if (status == 0) { - TRACE_L("line discipline %d registered", N_R3964); - TRACE_L("flags=%x num=%x", tty_ldisc_N_R3964.flags, - tty_ldisc_N_R3964.num); - TRACE_L("open=%p", tty_ldisc_N_R3964.open); - TRACE_L("tty_ldisc_N_R3964 = %p", &tty_ldisc_N_R3964); - } else { - printk(KERN_ERR "r3964: error registering line discipline: " - "%d\n", status); - } - return status; -} - -module_init(r3964_init); -module_exit(r3964_exit); - -/************************************************************* - * Protocol implementation routines - *************************************************************/ - -static void add_tx_queue(struct r3964_info *pInfo, - struct r3964_block_header *pHeader) -{ - unsigned long flags; - - spin_lock_irqsave(&pInfo->lock, flags); - - pHeader->next = NULL; - - if (pInfo->tx_last == NULL) { - pInfo->tx_first = pInfo->tx_last = pHeader; - } else { - pInfo->tx_last->next = pHeader; - pInfo->tx_last = pHeader; - } - - spin_unlock_irqrestore(&pInfo->lock, flags); - - TRACE_Q("add_tx_queue %p, length %d, tx_first = %p", - pHeader, pHeader->length, pInfo->tx_first); -} - -static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code) -{ - struct r3964_block_header *pHeader; - unsigned long flags; -#ifdef DEBUG_QUEUE - struct r3964_block_header *pDump; -#endif - - pHeader = pInfo->tx_first; - - if (pHeader == NULL) - return; - -#ifdef DEBUG_QUEUE - printk("r3964: remove_from_tx_queue: %p, length %u - ", - pHeader, pHeader->length); - for (pDump = pHeader; pDump; pDump = pDump->next) - printk("%p ", pDump); - printk("\n"); -#endif - - if (pHeader->owner) { - if (error_code) { - add_msg(pHeader->owner, R3964_MSG_ACK, 0, - error_code, NULL); - } else { - add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length, - error_code, NULL); - } - wake_up_interruptible(&pInfo->read_wait); - } - - spin_lock_irqsave(&pInfo->lock, flags); - - pInfo->tx_first = pHeader->next; - if (pInfo->tx_first == NULL) { - pInfo->tx_last = NULL; - } - - spin_unlock_irqrestore(&pInfo->lock, flags); - - kfree(pHeader); - TRACE_M("remove_from_tx_queue - kfree %p", pHeader); - - TRACE_Q("remove_from_tx_queue: tx_first = %p, tx_last = %p", - pInfo->tx_first, pInfo->tx_last); -} - -static void add_rx_queue(struct r3964_info *pInfo, - struct r3964_block_header *pHeader) -{ - unsigned long flags; - - spin_lock_irqsave(&pInfo->lock, flags); - - pHeader->next = NULL; - - if (pInfo->rx_last == NULL) { - pInfo->rx_first = pInfo->rx_last = pHeader; - } else { - pInfo->rx_last->next = pHeader; - pInfo->rx_last = pHeader; - } - pInfo->blocks_in_rx_queue++; - - spin_unlock_irqrestore(&pInfo->lock, flags); - - TRACE_Q("add_rx_queue: %p, length = %d, rx_first = %p, count = %d", - pHeader, pHeader->length, - pInfo->rx_first, pInfo->blocks_in_rx_queue); -} - -static void remove_from_rx_queue(struct r3964_info *pInfo, - struct r3964_block_header *pHeader) -{ - unsigned long flags; - struct r3964_block_header *pFind; - - if (pHeader == NULL) - return; - - TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", - pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); - TRACE_Q("remove_from_rx_queue: %p, length %u", - pHeader, pHeader->length); - - spin_lock_irqsave(&pInfo->lock, flags); - - if (pInfo->rx_first == pHeader) { - /* Remove the first block in the linked list: */ - pInfo->rx_first = pHeader->next; - - if (pInfo->rx_first == NULL) { - pInfo->rx_last = NULL; - } - pInfo->blocks_in_rx_queue--; - } else { - /* Find block to remove: */ - for (pFind = pInfo->rx_first; pFind; pFind = pFind->next) { - if (pFind->next == pHeader) { - /* Got it. */ - pFind->next = pHeader->next; - pInfo->blocks_in_rx_queue--; - if (pFind->next == NULL) { - /* Oh, removed the last one! */ - pInfo->rx_last = pFind; - } - break; - } - } - } - - spin_unlock_irqrestore(&pInfo->lock, flags); - - kfree(pHeader); - TRACE_M("remove_from_rx_queue - kfree %p", pHeader); - - TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", - pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); -} - -static void put_char(struct r3964_info *pInfo, unsigned char ch) -{ - struct tty_struct *tty = pInfo->tty; - /* FIXME: put_char should not be called from an IRQ */ - tty_put_char(tty, ch); - pInfo->bcc ^= ch; -} - -static void flush(struct r3964_info *pInfo) -{ - struct tty_struct *tty = pInfo->tty; - - if (tty == NULL || tty->ops->flush_chars == NULL) - return; - tty->ops->flush_chars(tty); -} - -static void trigger_transmit(struct r3964_info *pInfo) -{ - unsigned long flags; - - spin_lock_irqsave(&pInfo->lock, flags); - - if ((pInfo->state == R3964_IDLE) && (pInfo->tx_first != NULL)) { - pInfo->state = R3964_TX_REQUEST; - pInfo->nRetry = 0; - pInfo->flags &= ~R3964_ERROR; - mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); - - spin_unlock_irqrestore(&pInfo->lock, flags); - - TRACE_PS("trigger_transmit - sent STX"); - - put_char(pInfo, STX); - flush(pInfo); - - pInfo->bcc = 0; - } else { - spin_unlock_irqrestore(&pInfo->lock, flags); - } -} - -static void retry_transmit(struct r3964_info *pInfo) -{ - if (pInfo->nRetry < R3964_MAX_RETRIES) { - TRACE_PE("transmission failed. Retry #%d", pInfo->nRetry); - pInfo->bcc = 0; - put_char(pInfo, STX); - flush(pInfo); - pInfo->state = R3964_TX_REQUEST; - pInfo->nRetry++; - mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); - } else { - TRACE_PE("transmission failed after %d retries", - R3964_MAX_RETRIES); - - remove_from_tx_queue(pInfo, R3964_TX_FAIL); - - put_char(pInfo, NAK); - flush(pInfo); - pInfo->state = R3964_IDLE; - - trigger_transmit(pInfo); - } -} - -static void transmit_block(struct r3964_info *pInfo) -{ - struct tty_struct *tty = pInfo->tty; - struct r3964_block_header *pBlock = pInfo->tx_first; - int room = 0; - - if (tty == NULL || pBlock == NULL) { - return; - } - - room = tty_write_room(tty); - - TRACE_PS("transmit_block %p, room %d, length %d", - pBlock, room, pBlock->length); - - while (pInfo->tx_position < pBlock->length) { - if (room < 2) - break; - - if (pBlock->data[pInfo->tx_position] == DLE) { - /* send additional DLE char: */ - put_char(pInfo, DLE); - } - put_char(pInfo, pBlock->data[pInfo->tx_position++]); - - room--; - } - - if ((pInfo->tx_position == pBlock->length) && (room >= 3)) { - put_char(pInfo, DLE); - put_char(pInfo, ETX); - if (pInfo->flags & R3964_BCC) { - put_char(pInfo, pInfo->bcc); - } - pInfo->state = R3964_WAIT_FOR_TX_ACK; - mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); - } - flush(pInfo); -} - -static void on_receive_block(struct r3964_info *pInfo) -{ - unsigned int length; - struct r3964_client_info *pClient; - struct r3964_block_header *pBlock; - - length = pInfo->rx_position; - - /* compare byte checksum characters: */ - if (pInfo->flags & R3964_BCC) { - if (pInfo->bcc != pInfo->last_rx) { - TRACE_PE("checksum error - got %x but expected %x", - pInfo->last_rx, pInfo->bcc); - pInfo->flags |= R3964_CHECKSUM; - } - } - - /* check for errors (parity, overrun,...): */ - if (pInfo->flags & R3964_ERROR) { - TRACE_PE("on_receive_block - transmission failed error %x", - pInfo->flags & R3964_ERROR); - - put_char(pInfo, NAK); - flush(pInfo); - if (pInfo->nRetry < R3964_MAX_RETRIES) { - pInfo->state = R3964_WAIT_FOR_RX_REPEAT; - pInfo->nRetry++; - mod_timer(&pInfo->tmr, jiffies + R3964_TO_RX_PANIC); - } else { - TRACE_PE("on_receive_block - failed after max retries"); - pInfo->state = R3964_IDLE; - } - return; - } - - /* received block; submit DLE: */ - put_char(pInfo, DLE); - flush(pInfo); - del_timer_sync(&pInfo->tmr); - TRACE_PS(" rx success: got %d chars", length); - - /* prepare struct r3964_block_header: */ - pBlock = kmalloc(length + sizeof(struct r3964_block_header), - GFP_KERNEL); - TRACE_M("on_receive_block - kmalloc %p", pBlock); - - if (pBlock == NULL) - return; - - pBlock->length = length; - pBlock->data = ((unsigned char *)pBlock) + - sizeof(struct r3964_block_header); - pBlock->locks = 0; - pBlock->next = NULL; - pBlock->owner = NULL; - - memcpy(pBlock->data, pInfo->rx_buf, length); - - /* queue block into rx_queue: */ - add_rx_queue(pInfo, pBlock); - - /* notify attached client processes: */ - for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { - if (pClient->sig_flags & R3964_SIG_DATA) { - add_msg(pClient, R3964_MSG_DATA, length, R3964_OK, - pBlock); - } - } - wake_up_interruptible(&pInfo->read_wait); - - pInfo->state = R3964_IDLE; - - trigger_transmit(pInfo); -} - -static void receive_char(struct r3964_info *pInfo, const unsigned char c) -{ - switch (pInfo->state) { - case R3964_TX_REQUEST: - if (c == DLE) { - TRACE_PS("TX_REQUEST - got DLE"); - - pInfo->state = R3964_TRANSMITTING; - pInfo->tx_position = 0; - - transmit_block(pInfo); - } else if (c == STX) { - if (pInfo->nRetry == 0) { - TRACE_PE("TX_REQUEST - init conflict"); - if (pInfo->priority == R3964_SLAVE) { - goto start_receiving; - } - } else { - TRACE_PE("TX_REQUEST - secondary init " - "conflict!? Switching to SLAVE mode " - "for next rx."); - goto start_receiving; - } - } else { - TRACE_PE("TX_REQUEST - char != DLE: %x", c); - retry_transmit(pInfo); - } - break; - case R3964_TRANSMITTING: - if (c == NAK) { - TRACE_PE("TRANSMITTING - got NAK"); - retry_transmit(pInfo); - } else { - TRACE_PE("TRANSMITTING - got invalid char"); - - pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY; - mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); - } - break; - case R3964_WAIT_FOR_TX_ACK: - if (c == DLE) { - TRACE_PS("WAIT_FOR_TX_ACK - got DLE"); - remove_from_tx_queue(pInfo, R3964_OK); - - pInfo->state = R3964_IDLE; - trigger_transmit(pInfo); - } else { - retry_transmit(pInfo); - } - break; - case R3964_WAIT_FOR_RX_REPEAT: - /* FALLTHROUGH */ - case R3964_IDLE: - if (c == STX) { - /* Prevent rx_queue from overflow: */ - if (pInfo->blocks_in_rx_queue >= - R3964_MAX_BLOCKS_IN_RX_QUEUE) { - TRACE_PE("IDLE - got STX but no space in " - "rx_queue!"); - pInfo->state = R3964_WAIT_FOR_RX_BUF; - mod_timer(&pInfo->tmr, - jiffies + R3964_TO_NO_BUF); - break; - } -start_receiving: - /* Ok, start receiving: */ - TRACE_PS("IDLE - got STX"); - pInfo->rx_position = 0; - pInfo->last_rx = 0; - pInfo->flags &= ~R3964_ERROR; - pInfo->state = R3964_RECEIVING; - mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); - pInfo->nRetry = 0; - put_char(pInfo, DLE); - flush(pInfo); - pInfo->bcc = 0; - } - break; - case R3964_RECEIVING: - if (pInfo->rx_position < RX_BUF_SIZE) { - pInfo->bcc ^= c; - - if (c == DLE) { - if (pInfo->last_rx == DLE) { - pInfo->last_rx = 0; - goto char_to_buf; - } - pInfo->last_rx = DLE; - break; - } else if ((c == ETX) && (pInfo->last_rx == DLE)) { - if (pInfo->flags & R3964_BCC) { - pInfo->state = R3964_WAIT_FOR_BCC; - mod_timer(&pInfo->tmr, - jiffies + R3964_TO_ZVZ); - } else { - on_receive_block(pInfo); - } - } else { - pInfo->last_rx = c; -char_to_buf: - pInfo->rx_buf[pInfo->rx_position++] = c; - mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); - } - } - /* else: overflow-msg? BUF_SIZE>MTU; should not happen? */ - break; - case R3964_WAIT_FOR_BCC: - pInfo->last_rx = c; - on_receive_block(pInfo); - break; - } -} - -static void receive_error(struct r3964_info *pInfo, const char flag) -{ - switch (flag) { - case TTY_NORMAL: - break; - case TTY_BREAK: - TRACE_PE("received break"); - pInfo->flags |= R3964_BREAK; - break; - case TTY_PARITY: - TRACE_PE("parity error"); - pInfo->flags |= R3964_PARITY; - break; - case TTY_FRAME: - TRACE_PE("frame error"); - pInfo->flags |= R3964_FRAME; - break; - case TTY_OVERRUN: - TRACE_PE("frame overrun"); - pInfo->flags |= R3964_OVERRUN; - break; - default: - TRACE_PE("receive_error - unknown flag %d", flag); - pInfo->flags |= R3964_UNKNOWN; - break; - } -} - -static void on_timeout(unsigned long priv) -{ - struct r3964_info *pInfo = (void *)priv; - - switch (pInfo->state) { - case R3964_TX_REQUEST: - TRACE_PE("TX_REQUEST - timeout"); - retry_transmit(pInfo); - break; - case R3964_WAIT_ZVZ_BEFORE_TX_RETRY: - put_char(pInfo, NAK); - flush(pInfo); - retry_transmit(pInfo); - break; - case R3964_WAIT_FOR_TX_ACK: - TRACE_PE("WAIT_FOR_TX_ACK - timeout"); - retry_transmit(pInfo); - break; - case R3964_WAIT_FOR_RX_BUF: - TRACE_PE("WAIT_FOR_RX_BUF - timeout"); - put_char(pInfo, NAK); - flush(pInfo); - pInfo->state = R3964_IDLE; - break; - case R3964_RECEIVING: - TRACE_PE("RECEIVING - timeout after %d chars", - pInfo->rx_position); - put_char(pInfo, NAK); - flush(pInfo); - pInfo->state = R3964_IDLE; - break; - case R3964_WAIT_FOR_RX_REPEAT: - TRACE_PE("WAIT_FOR_RX_REPEAT - timeout"); - pInfo->state = R3964_IDLE; - break; - case R3964_WAIT_FOR_BCC: - TRACE_PE("WAIT_FOR_BCC - timeout"); - put_char(pInfo, NAK); - flush(pInfo); - pInfo->state = R3964_IDLE; - break; - } -} - -static struct r3964_client_info *findClient(struct r3964_info *pInfo, - struct pid *pid) -{ - struct r3964_client_info *pClient; - - for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { - if (pClient->pid == pid) { - return pClient; - } - } - return NULL; -} - -static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg) -{ - struct r3964_client_info *pClient; - struct r3964_client_info **ppClient; - struct r3964_message *pMsg; - - if ((arg & R3964_SIG_ALL) == 0) { - /* Remove client from client list */ - for (ppClient = &pInfo->firstClient; *ppClient; - ppClient = &(*ppClient)->next) { - pClient = *ppClient; - - if (pClient->pid == pid) { - TRACE_PS("removing client %d from client list", - pid_nr(pid)); - *ppClient = pClient->next; - while (pClient->msg_count) { - pMsg = remove_msg(pInfo, pClient); - if (pMsg) { - kfree(pMsg); - TRACE_M("enable_signals - msg " - "kfree %p", pMsg); - } - } - put_pid(pClient->pid); - kfree(pClient); - TRACE_M("enable_signals - kfree %p", pClient); - return 0; - } - } - return -EINVAL; - } else { - pClient = findClient(pInfo, pid); - if (pClient) { - /* update signal options */ - pClient->sig_flags = arg; - } else { - /* add client to client list */ - pClient = kmalloc(sizeof(struct r3964_client_info), - GFP_KERNEL); - TRACE_M("enable_signals - kmalloc %p", pClient); - if (pClient == NULL) - return -ENOMEM; - - TRACE_PS("add client %d to client list", pid_nr(pid)); - spin_lock_init(&pClient->lock); - pClient->sig_flags = arg; - pClient->pid = get_pid(pid); - pClient->next = pInfo->firstClient; - pClient->first_msg = NULL; - pClient->last_msg = NULL; - pClient->next_block_to_read = NULL; - pClient->msg_count = 0; - pInfo->firstClient = pClient; - } - } - - return 0; -} - -static int read_telegram(struct r3964_info *pInfo, struct pid *pid, - unsigned char __user * buf) -{ - struct r3964_client_info *pClient; - struct r3964_block_header *block; - - if (!buf) { - return -EINVAL; - } - - pClient = findClient(pInfo, pid); - if (pClient == NULL) { - return -EINVAL; - } - - block = pClient->next_block_to_read; - if (!block) { - return 0; - } else { - if (copy_to_user(buf, block->data, block->length)) - return -EFAULT; - - remove_client_block(pInfo, pClient); - return block->length; - } - - return -EINVAL; -} - -static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, - int error_code, struct r3964_block_header *pBlock) -{ - struct r3964_message *pMsg; - unsigned long flags; - - if (pClient->msg_count < R3964_MAX_MSG_COUNT - 1) { -queue_the_message: - - pMsg = kmalloc(sizeof(struct r3964_message), - error_code ? GFP_ATOMIC : GFP_KERNEL); - TRACE_M("add_msg - kmalloc %p", pMsg); - if (pMsg == NULL) { - return; - } - - spin_lock_irqsave(&pClient->lock, flags); - - pMsg->msg_id = msg_id; - pMsg->arg = arg; - pMsg->error_code = error_code; - pMsg->block = pBlock; - pMsg->next = NULL; - - if (pClient->last_msg == NULL) { - pClient->first_msg = pClient->last_msg = pMsg; - } else { - pClient->last_msg->next = pMsg; - pClient->last_msg = pMsg; - } - - pClient->msg_count++; - - if (pBlock != NULL) { - pBlock->locks++; - } - spin_unlock_irqrestore(&pClient->lock, flags); - } else { - if ((pClient->last_msg->msg_id == R3964_MSG_ACK) - && (pClient->last_msg->error_code == R3964_OVERFLOW)) { - pClient->last_msg->arg++; - TRACE_PE("add_msg - inc prev OVERFLOW-msg"); - } else { - msg_id = R3964_MSG_ACK; - arg = 0; - error_code = R3964_OVERFLOW; - pBlock = NULL; - TRACE_PE("add_msg - queue OVERFLOW-msg"); - goto queue_the_message; - } - } - /* Send SIGIO signal to client process: */ - if (pClient->sig_flags & R3964_USE_SIGIO) { - kill_pid(pClient->pid, SIGIO, 1); - } -} - -static struct r3964_message *remove_msg(struct r3964_info *pInfo, - struct r3964_client_info *pClient) -{ - struct r3964_message *pMsg = NULL; - unsigned long flags; - - if (pClient->first_msg) { - spin_lock_irqsave(&pClient->lock, flags); - - pMsg = pClient->first_msg; - pClient->first_msg = pMsg->next; - if (pClient->first_msg == NULL) { - pClient->last_msg = NULL; - } - - pClient->msg_count--; - if (pMsg->block) { - remove_client_block(pInfo, pClient); - pClient->next_block_to_read = pMsg->block; - } - spin_unlock_irqrestore(&pClient->lock, flags); - } - return pMsg; -} - -static void remove_client_block(struct r3964_info *pInfo, - struct r3964_client_info *pClient) -{ - struct r3964_block_header *block; - - TRACE_PS("remove_client_block PID %d", pid_nr(pClient->pid)); - - block = pClient->next_block_to_read; - if (block) { - block->locks--; - if (block->locks == 0) { - remove_from_rx_queue(pInfo, block); - } - } - pClient->next_block_to_read = NULL; -} - -/************************************************************* - * Line discipline routines - *************************************************************/ - -static int r3964_open(struct tty_struct *tty) -{ - struct r3964_info *pInfo; - - TRACE_L("open"); - TRACE_L("tty=%p, PID=%d, disc_data=%p", - tty, current->pid, tty->disc_data); - - pInfo = kmalloc(sizeof(struct r3964_info), GFP_KERNEL); - TRACE_M("r3964_open - info kmalloc %p", pInfo); - - if (!pInfo) { - printk(KERN_ERR "r3964: failed to alloc info structure\n"); - return -ENOMEM; - } - - pInfo->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL); - TRACE_M("r3964_open - rx_buf kmalloc %p", pInfo->rx_buf); - - if (!pInfo->rx_buf) { - printk(KERN_ERR "r3964: failed to alloc receive buffer\n"); - kfree(pInfo); - TRACE_M("r3964_open - info kfree %p", pInfo); - return -ENOMEM; - } - - pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL); - TRACE_M("r3964_open - tx_buf kmalloc %p", pInfo->tx_buf); - - if (!pInfo->tx_buf) { - printk(KERN_ERR "r3964: failed to alloc transmit buffer\n"); - kfree(pInfo->rx_buf); - TRACE_M("r3964_open - rx_buf kfree %p", pInfo->rx_buf); - kfree(pInfo); - TRACE_M("r3964_open - info kfree %p", pInfo); - return -ENOMEM; - } - - spin_lock_init(&pInfo->lock); - pInfo->tty = tty; - init_waitqueue_head(&pInfo->read_wait); - pInfo->priority = R3964_MASTER; - pInfo->rx_first = pInfo->rx_last = NULL; - pInfo->tx_first = pInfo->tx_last = NULL; - pInfo->rx_position = 0; - pInfo->tx_position = 0; - pInfo->last_rx = 0; - pInfo->blocks_in_rx_queue = 0; - pInfo->firstClient = NULL; - pInfo->state = R3964_IDLE; - pInfo->flags = R3964_DEBUG; - pInfo->nRetry = 0; - - tty->disc_data = pInfo; - tty->receive_room = 65536; - - setup_timer(&pInfo->tmr, on_timeout, (unsigned long)pInfo); - - return 0; -} - -static void r3964_close(struct tty_struct *tty) -{ - struct r3964_info *pInfo = tty->disc_data; - struct r3964_client_info *pClient, *pNext; - struct r3964_message *pMsg; - struct r3964_block_header *pHeader, *pNextHeader; - unsigned long flags; - - TRACE_L("close"); - - /* - * Make sure that our task queue isn't activated. If it - * is, take it out of the linked list. - */ - del_timer_sync(&pInfo->tmr); - - /* Remove client-structs and message queues: */ - pClient = pInfo->firstClient; - while (pClient) { - pNext = pClient->next; - while (pClient->msg_count) { - pMsg = remove_msg(pInfo, pClient); - if (pMsg) { - kfree(pMsg); - TRACE_M("r3964_close - msg kfree %p", pMsg); - } - } - put_pid(pClient->pid); - kfree(pClient); - TRACE_M("r3964_close - client kfree %p", pClient); - pClient = pNext; - } - /* Remove jobs from tx_queue: */ - spin_lock_irqsave(&pInfo->lock, flags); - pHeader = pInfo->tx_first; - pInfo->tx_first = pInfo->tx_last = NULL; - spin_unlock_irqrestore(&pInfo->lock, flags); - - while (pHeader) { - pNextHeader = pHeader->next; - kfree(pHeader); - pHeader = pNextHeader; - } - - /* Free buffers: */ - wake_up_interruptible(&pInfo->read_wait); - kfree(pInfo->rx_buf); - TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf); - kfree(pInfo->tx_buf); - TRACE_M("r3964_close - tx_buf kfree %p", pInfo->tx_buf); - kfree(pInfo); - TRACE_M("r3964_close - info kfree %p", pInfo); -} - -static ssize_t r3964_read(struct tty_struct *tty, struct file *file, - unsigned char __user * buf, size_t nr) -{ - struct r3964_info *pInfo = tty->disc_data; - struct r3964_client_info *pClient; - struct r3964_message *pMsg; - struct r3964_client_message theMsg; - int ret; - - TRACE_L("read()"); - - tty_lock(); - - pClient = findClient(pInfo, task_pid(current)); - if (pClient) { - pMsg = remove_msg(pInfo, pClient); - if (pMsg == NULL) { - /* no messages available. */ - if (file->f_flags & O_NONBLOCK) { - ret = -EAGAIN; - goto unlock; - } - /* block until there is a message: */ - wait_event_interruptible_tty(pInfo->read_wait, - (pMsg = remove_msg(pInfo, pClient))); - } - - /* If we still haven't got a message, we must have been signalled */ - - if (!pMsg) { - ret = -EINTR; - goto unlock; - } - - /* deliver msg to client process: */ - theMsg.msg_id = pMsg->msg_id; - theMsg.arg = pMsg->arg; - theMsg.error_code = pMsg->error_code; - ret = sizeof(struct r3964_client_message); - - kfree(pMsg); - TRACE_M("r3964_read - msg kfree %p", pMsg); - - if (copy_to_user(buf, &theMsg, ret)) { - ret = -EFAULT; - goto unlock; - } - - TRACE_PS("read - return %d", ret); - goto unlock; - } - ret = -EPERM; -unlock: - tty_unlock(); - return ret; -} - -static ssize_t r3964_write(struct tty_struct *tty, struct file *file, - const unsigned char *data, size_t count) -{ - struct r3964_info *pInfo = tty->disc_data; - struct r3964_block_header *pHeader; - struct r3964_client_info *pClient; - unsigned char *new_data; - - TRACE_L("write request, %d characters", count); -/* - * Verify the pointers - */ - - if (!pInfo) - return -EIO; - -/* - * Ensure that the caller does not wish to send too much. - */ - if (count > R3964_MTU) { - if (pInfo->flags & R3964_DEBUG) { - TRACE_L(KERN_WARNING "r3964_write: truncating user " - "packet from %u to mtu %d", count, R3964_MTU); - } - count = R3964_MTU; - } -/* - * Allocate a buffer for the data and copy it from the buffer with header prepended - */ - new_data = kmalloc(count + sizeof(struct r3964_block_header), - GFP_KERNEL); - TRACE_M("r3964_write - kmalloc %p", new_data); - if (new_data == NULL) { - if (pInfo->flags & R3964_DEBUG) { - printk(KERN_ERR "r3964_write: no memory\n"); - } - return -ENOSPC; - } - - pHeader = (struct r3964_block_header *)new_data; - pHeader->data = new_data + sizeof(struct r3964_block_header); - pHeader->length = count; - pHeader->locks = 0; - pHeader->owner = NULL; - - tty_lock(); - - pClient = findClient(pInfo, task_pid(current)); - if (pClient) { - pHeader->owner = pClient; - } - - memcpy(pHeader->data, data, count); /* We already verified this */ - - if (pInfo->flags & R3964_DEBUG) { - dump_block(pHeader->data, count); - } - -/* - * Add buffer to transmit-queue: - */ - add_tx_queue(pInfo, pHeader); - trigger_transmit(pInfo); - - tty_unlock(); - - return 0; -} - -static int r3964_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - struct r3964_info *pInfo = tty->disc_data; - if (pInfo == NULL) - return -EINVAL; - switch (cmd) { - case R3964_ENABLE_SIGNALS: - return enable_signals(pInfo, task_pid(current), arg); - case R3964_SETPRIORITY: - if (arg < R3964_MASTER || arg > R3964_SLAVE) - return -EINVAL; - pInfo->priority = arg & 0xff; - return 0; - case R3964_USE_BCC: - if (arg) - pInfo->flags |= R3964_BCC; - else - pInfo->flags &= ~R3964_BCC; - return 0; - case R3964_READ_TELEGRAM: - return read_telegram(pInfo, task_pid(current), - (unsigned char __user *)arg); - default: - return -ENOIOCTLCMD; - } -} - -static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old) -{ - TRACE_L("set_termios"); -} - -/* Called without the kernel lock held - fine */ -static unsigned int r3964_poll(struct tty_struct *tty, struct file *file, - struct poll_table_struct *wait) -{ - struct r3964_info *pInfo = tty->disc_data; - struct r3964_client_info *pClient; - struct r3964_message *pMsg = NULL; - unsigned long flags; - int result = POLLOUT; - - TRACE_L("POLL"); - - pClient = findClient(pInfo, task_pid(current)); - if (pClient) { - poll_wait(file, &pInfo->read_wait, wait); - spin_lock_irqsave(&pInfo->lock, flags); - pMsg = pClient->first_msg; - spin_unlock_irqrestore(&pInfo->lock, flags); - if (pMsg) - result |= POLLIN | POLLRDNORM; - } else { - result = -EINVAL; - } - return result; -} - -static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) -{ - struct r3964_info *pInfo = tty->disc_data; - const unsigned char *p; - char *f, flags = 0; - int i; - - for (i = count, p = cp, f = fp; i; i--, p++) { - if (f) - flags = *f++; - if (flags == TTY_NORMAL) { - receive_char(pInfo, *p); - } else { - receive_error(pInfo, flags); - } - - } -} - -MODULE_LICENSE("GPL"); -MODULE_ALIAS_LDISC(N_R3964); diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c deleted file mode 100644 index 428f4fe..0000000 --- a/drivers/char/n_tty.c +++ /dev/null @@ -1,2121 +0,0 @@ -/* - * n_tty.c --- implements the N_TTY line discipline. - * - * This code used to be in tty_io.c, but things are getting hairy - * enough that it made sense to split things off. (The N_TTY - * processing has changed so much that it's hardly recognizable, - * anyway...) - * - * Note that the open routine for N_TTY is guaranteed never to return - * an error. This is because Linux will fall back to setting a line - * to N_TTY if it can not switch to any other line discipline. - * - * Written by Theodore Ts'o, Copyright 1994. - * - * This file also contains code originally written by Linus Torvalds, - * Copyright 1991, 1992, 1993, and by Julian Cowley, Copyright 1994. - * - * This file may be redistributed under the terms of the GNU General Public - * License. - * - * Reduced memory usage for older ARM systems - Russell King. - * - * 2000/01/20 Fixed SMP locking on put_tty_queue using bits of - * the patch by Andrew J. Kroll <ag784@freenet.buffalo.edu> - * who actually finally proved there really was a race. - * - * 2002/03/18 Implemented n_tty_wakeup to send SIGIO POLL_OUTs to - * waiting writing processes-Sapan Bhatia <sapan@corewars.org>. - * Also fixed a bug in BLOCKING mode where n_tty_write returns - * EAGAIN - */ - -#include <linux/types.h> -#include <linux/major.h> -#include <linux/errno.h> -#include <linux/signal.h> -#include <linux/fcntl.h> -#include <linux/sched.h> -#include <linux/interrupt.h> -#include <linux/tty.h> -#include <linux/timer.h> -#include <linux/ctype.h> -#include <linux/mm.h> -#include <linux/string.h> -#include <linux/slab.h> -#include <linux/poll.h> -#include <linux/bitops.h> -#include <linux/audit.h> -#include <linux/file.h> -#include <linux/uaccess.h> -#include <linux/module.h> - -#include <asm/system.h> - -/* number of characters left in xmit buffer before select has we have room */ -#define WAKEUP_CHARS 256 - -/* - * This defines the low- and high-watermarks for throttling and - * unthrottling the TTY driver. These watermarks are used for - * controlling the space in the read buffer. - */ -#define TTY_THRESHOLD_THROTTLE 128 /* now based on remaining room */ -#define TTY_THRESHOLD_UNTHROTTLE 128 - -/* - * Special byte codes used in the echo buffer to represent operations - * or special handling of characters. Bytes in the echo buffer that - * are not part of such special blocks are treated as normal character - * codes. - */ -#define ECHO_OP_START 0xff -#define ECHO_OP_MOVE_BACK_COL 0x80 -#define ECHO_OP_SET_CANON_COL 0x81 -#define ECHO_OP_ERASE_TAB 0x82 - -static inline int tty_put_user(struct tty_struct *tty, unsigned char x, - unsigned char __user *ptr) -{ - tty_audit_add_data(tty, &x, 1); - return put_user(x, ptr); -} - -/** - * n_tty_set__room - receive space - * @tty: terminal - * - * Called by the driver to find out how much data it is - * permitted to feed to the line discipline without any being lost - * and thus to manage flow control. Not serialized. Answers for the - * "instant". - */ - -static void n_tty_set_room(struct tty_struct *tty) -{ - /* tty->read_cnt is not read locked ? */ - int left = N_TTY_BUF_SIZE - tty->read_cnt - 1; - - /* - * If we are doing input canonicalization, and there are no - * pending newlines, let characters through without limit, so - * that erase characters will be handled. Other excess - * characters will be beeped. - */ - if (left <= 0) - left = tty->icanon && !tty->canon_data; - tty->receive_room = left; -} - -static void put_tty_queue_nolock(unsigned char c, struct tty_struct *tty) -{ - if (tty->read_cnt < N_TTY_BUF_SIZE) { - tty->read_buf[tty->read_head] = c; - tty->read_head = (tty->read_head + 1) & (N_TTY_BUF_SIZE-1); - tty->read_cnt++; - } -} - -/** - * put_tty_queue - add character to tty - * @c: character - * @tty: tty device - * - * Add a character to the tty read_buf queue. This is done under the - * read_lock to serialize character addition and also to protect us - * against parallel reads or flushes - */ - -static void put_tty_queue(unsigned char c, struct tty_struct *tty) -{ - unsigned long flags; - /* - * The problem of stomping on the buffers ends here. - * Why didn't anyone see this one coming? --AJK - */ - spin_lock_irqsave(&tty->read_lock, flags); - put_tty_queue_nolock(c, tty); - spin_unlock_irqrestore(&tty->read_lock, flags); -} - -/** - * check_unthrottle - allow new receive data - * @tty; tty device - * - * Check whether to call the driver unthrottle functions - * - * Can sleep, may be called under the atomic_read_lock mutex but - * this is not guaranteed. - */ -static void check_unthrottle(struct tty_struct *tty) -{ - if (tty->count) - tty_unthrottle(tty); -} - -/** - * reset_buffer_flags - reset buffer state - * @tty: terminal to reset - * - * Reset the read buffer counters, clear the flags, - * and make sure the driver is unthrottled. Called - * from n_tty_open() and n_tty_flush_buffer(). - * - * Locking: tty_read_lock for read fields. - */ - -static void reset_buffer_flags(struct tty_struct *tty) -{ - unsigned long flags; - - spin_lock_irqsave(&tty->read_lock, flags); - tty->read_head = tty->read_tail = tty->read_cnt = 0; - spin_unlock_irqrestore(&tty->read_lock, flags); - - mutex_lock(&tty->echo_lock); - tty->echo_pos = tty->echo_cnt = tty->echo_overrun = 0; - mutex_unlock(&tty->echo_lock); - - tty->canon_head = tty->canon_data = tty->erasing = 0; - memset(&tty->read_flags, 0, sizeof tty->read_flags); - n_tty_set_room(tty); - check_unthrottle(tty); -} - -/** - * n_tty_flush_buffer - clean input queue - * @tty: terminal device - * - * Flush the input buffer. Called when the line discipline is - * being closed, when the tty layer wants the buffer flushed (eg - * at hangup) or when the N_TTY line discipline internally has to - * clean the pending queue (for example some signals). - * - * Locking: ctrl_lock, read_lock. - */ - -static void n_tty_flush_buffer(struct tty_struct *tty) -{ - unsigned long flags; - /* clear everything and unthrottle the driver */ - reset_buffer_flags(tty); - - if (!tty->link) - return; - - spin_lock_irqsave(&tty->ctrl_lock, flags); - if (tty->link->packet) { - tty->ctrl_status |= TIOCPKT_FLUSHREAD; - wake_up_interruptible(&tty->link->read_wait); - } - spin_unlock_irqrestore(&tty->ctrl_lock, flags); -} - -/** - * n_tty_chars_in_buffer - report available bytes - * @tty: tty device - * - * Report the number of characters buffered to be delivered to user - * at this instant in time. - * - * Locking: read_lock - */ - -static ssize_t n_tty_chars_in_buffer(struct tty_struct *tty) -{ - unsigned long flags; - ssize_t n = 0; - - spin_lock_irqsave(&tty->read_lock, flags); - if (!tty->icanon) { - n = tty->read_cnt; - } else if (tty->canon_data) { - n = (tty->canon_head > tty->read_tail) ? - tty->canon_head - tty->read_tail : - tty->canon_head + (N_TTY_BUF_SIZE - tty->read_tail); - } - spin_unlock_irqrestore(&tty->read_lock, flags); - return n; -} - -/** - * is_utf8_continuation - utf8 multibyte check - * @c: byte to check - * - * Returns true if the utf8 character 'c' is a multibyte continuation - * character. We use this to correctly compute the on screen size - * of the character when printing - */ - -static inline int is_utf8_continuation(unsigned char c) -{ - return (c & 0xc0) == 0x80; -} - -/** - * is_continuation - multibyte check - * @c: byte to check - * - * Returns true if the utf8 character 'c' is a multibyte continuation - * character and the terminal is in unicode mode. - */ - -static inline int is_continuation(unsigned char c, struct tty_struct *tty) -{ - return I_IUTF8(tty) && is_utf8_continuation(c); -} - -/** - * do_output_char - output one character - * @c: character (or partial unicode symbol) - * @tty: terminal device - * @space: space available in tty driver write buffer - * - * This is a helper function that handles one output character - * (including special characters like TAB, CR, LF, etc.), - * doing OPOST processing and putting the results in the - * tty driver's write buffer. - * - * Note that Linux currently ignores TABDLY, CRDLY, VTDLY, FFDLY - * and NLDLY. They simply aren't relevant in the world today. - * If you ever need them, add them here. - * - * Returns the number of bytes of buffer space used or -1 if - * no space left. - * - * Locking: should be called under the output_lock to protect - * the column state and space left in the buffer - */ - -static int do_output_char(unsigned char c, struct tty_struct *tty, int space) -{ - int spaces; - - if (!space) - return -1; - - switch (c) { - case '\n': - if (O_ONLRET(tty)) - tty->column = 0; - if (O_ONLCR(tty)) { - if (space < 2) - return -1; - tty->canon_column = tty->column = 0; - tty->ops->write(tty, "\r\n", 2); - return 2; - } - tty->canon_column = tty->column; - break; - case '\r': - if (O_ONOCR(tty) && tty->column == 0) - return 0; - if (O_OCRNL(tty)) { - c = '\n'; - if (O_ONLRET(tty)) - tty->canon_column = tty->column = 0; - break; - } - tty->canon_column = tty->column = 0; - break; - case '\t': - spaces = 8 - (tty->column & 7); - if (O_TABDLY(tty) == XTABS) { - if (space < spaces) - return -1; - tty->column += spaces; - tty->ops->write(tty, " ", spaces); - return spaces; - } - tty->column += spaces; - break; - case '\b': - if (tty->column > 0) - tty->column--; - break; - default: - if (!iscntrl(c)) { - if (O_OLCUC(tty)) - c = toupper(c); - if (!is_continuation(c, tty)) - tty->column++; - } - break; - } - - tty_put_char(tty, c); - return 1; -} - -/** - * process_output - output post processor - * @c: character (or partial unicode symbol) - * @tty: terminal device - * - * Output one character with OPOST processing. - * Returns -1 when the output device is full and the character - * must be retried. - * - * Locking: output_lock to protect column state and space left - * (also, this is called from n_tty_write under the - * tty layer write lock) - */ - -static int process_output(unsigned char c, struct tty_struct *tty) -{ - int space, retval; - - mutex_lock(&tty->output_lock); - - space = tty_write_room(tty); - retval = do_output_char(c, tty, space); - - mutex_unlock(&tty->output_lock); - if (retval < 0) - return -1; - else - return 0; -} - -/** - * process_output_block - block post processor - * @tty: terminal device - * @buf: character buffer - * @nr: number of bytes to output - * - * Output a block of characters with OPOST processing. - * Returns the number of characters output. - * - * This path is used to speed up block console writes, among other - * things when processing blocks of output data. It handles only - * the simple cases normally found and helps to generate blocks of - * symbols for the console driver and thus improve performance. - * - * Locking: output_lock to protect column state and space left - * (also, this is called from n_tty_write under the - * tty layer write lock) - */ - -static ssize_t process_output_block(struct tty_struct *tty, - const unsigned char *buf, unsigned int nr) -{ - int space; - int i; - const unsigned char *cp; - - mutex_lock(&tty->output_lock); - - space = tty_write_room(tty); - if (!space) { - mutex_unlock(&tty->output_lock); - return 0; - } - if (nr > space) - nr = space; - - for (i = 0, cp = buf; i < nr; i++, cp++) { - unsigned char c = *cp; - - switch (c) { - case '\n': - if (O_ONLRET(tty)) - tty->column = 0; - if (O_ONLCR(tty)) - goto break_out; - tty->canon_column = tty->column; - break; - case '\r': - if (O_ONOCR(tty) && tty->column == 0) - goto break_out; - if (O_OCRNL(tty)) - goto break_out; - tty->canon_column = tty->column = 0; - break; - case '\t': - goto break_out; - case '\b': - if (tty->column > 0) - tty->column--; - break; - default: - if (!iscntrl(c)) { - if (O_OLCUC(tty)) - goto break_out; - if (!is_continuation(c, tty)) - tty->column++; - } - break; - } - } -break_out: - i = tty->ops->write(tty, buf, i); - - mutex_unlock(&tty->output_lock); - return i; -} - -/** - * process_echoes - write pending echo characters - * @tty: terminal device - * - * Write previously buffered echo (and other ldisc-generated) - * characters to the tty. - * - * Characters generated by the ldisc (including echoes) need to - * be buffered because the driver's write buffer can fill during - * heavy program output. Echoing straight to the driver will - * often fail under these conditions, causing lost characters and - * resulting mismatches of ldisc state information. - * - * Since the ldisc state must represent the characters actually sent - * to the driver at the time of the write, operations like certain - * changes in column state are also saved in the buffer and executed - * here. - * - * A circular fifo buffer is used so that the most recent characters - * are prioritized. Also, when control characters are echoed with a - * prefixed "^", the pair is treated atomically and thus not separated. - * - * Locking: output_lock to protect column state and space left, - * echo_lock to protect the echo buffer - */ - -static void process_echoes(struct tty_struct *tty) -{ - int space, nr; - unsigned char c; - unsigned char *cp, *buf_end; - - if (!tty->echo_cnt) - return; - - mutex_lock(&tty->output_lock); - mutex_lock(&tty->echo_lock); - - space = tty_write_room(tty); - - buf_end = tty->echo_buf + N_TTY_BUF_SIZE; - cp = tty->echo_buf + tty->echo_pos; - nr = tty->echo_cnt; - while (nr > 0) { - c = *cp; - if (c == ECHO_OP_START) { - unsigned char op; - unsigned char *opp; - int no_space_left = 0; - - /* - * If the buffer byte is the start of a multi-byte - * operation, get the next byte, which is either the - * op code or a control character value. - */ - opp = cp + 1; - if (opp == buf_end) - opp -= N_TTY_BUF_SIZE; - op = *opp; - - switch (op) { - unsigned int num_chars, num_bs; - - case ECHO_OP_ERASE_TAB: - if (++opp == buf_end) - opp -= N_TTY_BUF_SIZE; - num_chars = *opp; - - /* - * Determine how many columns to go back - * in order to erase the tab. - * This depends on the number of columns - * used by other characters within the tab - * area. If this (modulo 8) count is from - * the start of input rather than from a - * previous tab, we offset by canon column. - * Otherwise, tab spacing is normal. - */ - if (!(num_chars & 0x80)) - num_chars += tty->canon_column; - num_bs = 8 - (num_chars & 7); - - if (num_bs > space) { - no_space_left = 1; - break; - } - space -= num_bs; - while (num_bs--) { - tty_put_char(tty, '\b'); - if (tty->column > 0) - tty->column--; - } - cp += 3; - nr -= 3; - break; - - case ECHO_OP_SET_CANON_COL: - tty->canon_column = tty->column; - cp += 2; - nr -= 2; - break; - - case ECHO_OP_MOVE_BACK_COL: - if (tty->column > 0) - tty->column--; - cp += 2; - nr -= 2; - break; - - case ECHO_OP_START: - /* This is an escaped echo op start code */ - if (!space) { - no_space_left = 1; - break; - } - tty_put_char(tty, ECHO_OP_START); - tty->column++; - space--; - cp += 2; - nr -= 2; - break; - - default: - /* - * If the op is not a special byte code, - * it is a ctrl char tagged to be echoed - * as "^X" (where X is the letter - * representing the control char). - * Note that we must ensure there is - * enough space for the whole ctrl pair. - * - */ - if (space < 2) { - no_space_left = 1; - break; - } - tty_put_char(tty, '^'); - tty_put_char(tty, op ^ 0100); - tty->column += 2; - space -= 2; - cp += 2; - nr -= 2; - } - - if (no_space_left) - break; - } else { - if (O_OPOST(tty) && - !(test_bit(TTY_HW_COOK_OUT, &tty->flags))) { - int retval = do_output_char(c, tty, space); - if (retval < 0) - break; - space -= retval; - } else { - if (!space) - break; - tty_put_char(tty, c); - space -= 1; - } - cp += 1; - nr -= 1; - } - - /* When end of circular buffer reached, wrap around */ - if (cp >= buf_end) - cp -= N_TTY_BUF_SIZE; - } - - if (nr == 0) { - tty->echo_pos = 0; - tty->echo_cnt = 0; - tty->echo_overrun = 0; - } else { - int num_processed = tty->echo_cnt - nr; - tty->echo_pos += num_processed; - tty->echo_pos &= N_TTY_BUF_SIZE - 1; - tty->echo_cnt = nr; - if (num_processed > 0) - tty->echo_overrun = 0; - } - - mutex_unlock(&tty->echo_lock); - mutex_unlock(&tty->output_lock); - - if (tty->ops->flush_chars) - tty->ops->flush_chars(tty); -} - -/** - * add_echo_byte - add a byte to the echo buffer - * @c: unicode byte to echo - * @tty: terminal device - * - * Add a character or operation byte to the echo buffer. - * - * Should be called under the echo lock to protect the echo buffer. - */ - -static void add_echo_byte(unsigned char c, struct tty_struct *tty) -{ - int new_byte_pos; - - if (tty->echo_cnt == N_TTY_BUF_SIZE) { - /* Circular buffer is already at capacity */ - new_byte_pos = tty->echo_pos; - - /* - * Since the buffer start position needs to be advanced, - * be sure to step by a whole operation byte group. - */ - if (tty->echo_buf[tty->echo_pos] == ECHO_OP_START) { - if (tty->echo_buf[(tty->echo_pos + 1) & - (N_TTY_BUF_SIZE - 1)] == - ECHO_OP_ERASE_TAB) { - tty->echo_pos += 3; - tty->echo_cnt -= 2; - } else { - tty->echo_pos += 2; - tty->echo_cnt -= 1; - } - } else { - tty->echo_pos++; - } - tty->echo_pos &= N_TTY_BUF_SIZE - 1; - - tty->echo_overrun = 1; - } else { - new_byte_pos = tty->echo_pos + tty->echo_cnt; - new_byte_pos &= N_TTY_BUF_SIZE - 1; - tty->echo_cnt++; - } - - tty->echo_buf[new_byte_pos] = c; -} - -/** - * echo_move_back_col - add operation to move back a column - * @tty: terminal device - * - * Add an operation to the echo buffer to move back one column. - * - * Locking: echo_lock to protect the echo buffer - */ - -static void echo_move_back_col(struct tty_struct *tty) -{ - mutex_lock(&tty->echo_lock); - - add_echo_byte(ECHO_OP_START, tty); - add_echo_byte(ECHO_OP_MOVE_BACK_COL, tty); - - mutex_unlock(&tty->echo_lock); -} - -/** - * echo_set_canon_col - add operation to set the canon column - * @tty: terminal device - * - * Add an operation to the echo buffer to set the canon column - * to the current column. - * - * Locking: echo_lock to protect the echo buffer - */ - -static void echo_set_canon_col(struct tty_struct *tty) -{ - mutex_lock(&tty->echo_lock); - - add_echo_byte(ECHO_OP_START, tty); - add_echo_byte(ECHO_OP_SET_CANON_COL, tty); - - mutex_unlock(&tty->echo_lock); -} - -/** - * echo_erase_tab - add operation to erase a tab - * @num_chars: number of character columns already used - * @after_tab: true if num_chars starts after a previous tab - * @tty: terminal device - * - * Add an operation to the echo buffer to erase a tab. - * - * Called by the eraser function, which knows how many character - * columns have been used since either a previous tab or the start - * of input. This information will be used later, along with - * canon column (if applicable), to go back the correct number - * of columns. - * - * Locking: echo_lock to protect the echo buffer - */ - -static void echo_erase_tab(unsigned int num_chars, int after_tab, - struct tty_struct *tty) -{ - mutex_lock(&tty->echo_lock); - - add_echo_byte(ECHO_OP_START, tty); - add_echo_byte(ECHO_OP_ERASE_TAB, tty); - - /* We only need to know this modulo 8 (tab spacing) */ - num_chars &= 7; - - /* Set the high bit as a flag if num_chars is after a previous tab */ - if (after_tab) - num_chars |= 0x80; - - add_echo_byte(num_chars, tty); - - mutex_unlock(&tty->echo_lock); -} - -/** - * echo_char_raw - echo a character raw - * @c: unicode byte to echo - * @tty: terminal device - * - * Echo user input back onto the screen. This must be called only when - * L_ECHO(tty) is true. Called from the driver receive_buf path. - * - * This variant does not treat control characters specially. - * - * Locking: echo_lock to protect the echo buffer - */ - -static void echo_char_raw(unsigned char c, struct tty_struct *tty) -{ - mutex_lock(&tty->echo_lock); - - if (c == ECHO_OP_START) { - add_echo_byte(ECHO_OP_START, tty); - add_echo_byte(ECHO_OP_START, tty); - } else { - add_echo_byte(c, tty); - } - - mutex_unlock(&tty->echo_lock); -} - -/** - * echo_char - echo a character - * @c: unicode byte to echo - * @tty: terminal device - * - * Echo user input back onto the screen. This must be called only when - * L_ECHO(tty) is true. Called from the driver receive_buf path. - * - * This variant tags control characters to be echoed as "^X" - * (where X is the letter representing the control char). - * - * Locking: echo_lock to protect the echo buffer - */ - -static void echo_char(unsigned char c, struct tty_struct *tty) -{ - mutex_lock(&tty->echo_lock); - - if (c == ECHO_OP_START) { - add_echo_byte(ECHO_OP_START, tty); - add_echo_byte(ECHO_OP_START, tty); - } else { - if (L_ECHOCTL(tty) && iscntrl(c) && c != '\t') - add_echo_byte(ECHO_OP_START, tty); - add_echo_byte(c, tty); - } - - mutex_unlock(&tty->echo_lock); -} - -/** - * finish_erasing - complete erase - * @tty: tty doing the erase - */ - -static inline void finish_erasing(struct tty_struct *tty) -{ - if (tty->erasing) { - echo_char_raw('/', tty); - tty->erasing = 0; - } -} - -/** - * eraser - handle erase function - * @c: character input - * @tty: terminal device - * - * Perform erase and necessary output when an erase character is - * present in the stream from the driver layer. Handles the complexities - * of UTF-8 multibyte symbols. - * - * Locking: read_lock for tty buffers - */ - -static void eraser(unsigned char c, struct tty_struct *tty) -{ - enum { ERASE, WERASE, KILL } kill_type; - int head, seen_alnums, cnt; - unsigned long flags; - - /* FIXME: locking needed ? */ - if (tty->read_head == tty->canon_head) { - /* process_output('\a', tty); */ /* what do you think? */ - return; - } - if (c == ERASE_CHAR(tty)) - kill_type = ERASE; - else if (c == WERASE_CHAR(tty)) - kill_type = WERASE; - else { - if (!L_ECHO(tty)) { - spin_lock_irqsave(&tty->read_lock, flags); - tty->read_cnt -= ((tty->read_head - tty->canon_head) & - (N_TTY_BUF_SIZE - 1)); - tty->read_head = tty->canon_head; - spin_unlock_irqrestore(&tty->read_lock, flags); - return; - } - if (!L_ECHOK(tty) || !L_ECHOKE(tty) || !L_ECHOE(tty)) { - spin_lock_irqsave(&tty->read_lock, flags); - tty->read_cnt -= ((tty->read_head - tty->canon_head) & - (N_TTY_BUF_SIZE - 1)); - tty->read_head = tty->canon_head; - spin_unlock_irqrestore(&tty->read_lock, flags); - finish_erasing(tty); - echo_char(KILL_CHAR(tty), tty); - /* Add a newline if ECHOK is on and ECHOKE is off. */ - if (L_ECHOK(tty)) - echo_char_raw('\n', tty); - return; - } - kill_type = KILL; - } - - seen_alnums = 0; - /* FIXME: Locking ?? */ - while (tty->read_head != tty->canon_head) { - head = tty->read_head; - - /* erase a single possibly multibyte character */ - do { - head = (head - 1) & (N_TTY_BUF_SIZE-1); - c = tty->read_buf[head]; - } while (is_continuation(c, tty) && head != tty->canon_head); - - /* do not partially erase */ - if (is_continuation(c, tty)) - break; - - if (kill_type == WERASE) { - /* Equivalent to BSD's ALTWERASE. */ - if (isalnum(c) || c == '_') - seen_alnums++; - else if (seen_alnums) - break; - } - cnt = (tty->read_head - head) & (N_TTY_BUF_SIZE-1); - spin_lock_irqsave(&tty->read_lock, flags); - tty->read_head = head; - tty->read_cnt -= cnt; - spin_unlock_irqrestore(&tty->read_lock, flags); - if (L_ECHO(tty)) { - if (L_ECHOPRT(tty)) { - if (!tty->erasing) { - echo_char_raw('\\', tty); - tty->erasing = 1; - } - /* if cnt > 1, output a multi-byte character */ - echo_char(c, tty); - while (--cnt > 0) { - head = (head+1) & (N_TTY_BUF_SIZE-1); - echo_char_raw(tty->read_buf[head], tty); - echo_move_back_col(tty); - } - } else if (kill_type == ERASE && !L_ECHOE(tty)) { - echo_char(ERASE_CHAR(tty), tty); - } else if (c == '\t') { - unsigned int num_chars = 0; - int after_tab = 0; - unsigned long tail = tty->read_head; - - /* - * Count the columns used for characters - * since the start of input or after a - * previous tab. - * This info is used to go back the correct - * number of columns. - */ - while (tail != tty->canon_head) { - tail = (tail-1) & (N_TTY_BUF_SIZE-1); - c = tty->read_buf[tail]; - if (c == '\t') { - after_tab = 1; - break; - } else if (iscntrl(c)) { - if (L_ECHOCTL(tty)) - num_chars += 2; - } else if (!is_continuation(c, tty)) { - num_chars++; - } - } - echo_erase_tab(num_chars, after_tab, tty); - } else { - if (iscntrl(c) && L_ECHOCTL(tty)) { - echo_char_raw('\b', tty); - echo_char_raw(' ', tty); - echo_char_raw('\b', tty); - } - if (!iscntrl(c) || L_ECHOCTL(tty)) { - echo_char_raw('\b', tty); - echo_char_raw(' ', tty); - echo_char_raw('\b', tty); - } - } - } - if (kill_type == ERASE) - break; - } - if (tty->read_head == tty->canon_head && L_ECHO(tty)) - finish_erasing(tty); -} - -/** - * isig - handle the ISIG optio - * @sig: signal - * @tty: terminal - * @flush: force flush - * - * Called when a signal is being sent due to terminal input. This - * may caus terminal flushing to take place according to the termios - * settings and character used. Called from the driver receive_buf - * path so serialized. - * - * Locking: ctrl_lock, read_lock (both via flush buffer) - */ - -static inline void isig(int sig, struct tty_struct *tty, int flush) -{ - if (tty->pgrp) - kill_pgrp(tty->pgrp, sig, 1); - if (flush || !L_NOFLSH(tty)) { - n_tty_flush_buffer(tty); - tty_driver_flush_buffer(tty); - } -} - -/** - * n_tty_receive_break - handle break - * @tty: terminal - * - * An RS232 break event has been hit in the incoming bitstream. This - * can cause a variety of events depending upon the termios settings. - * - * Called from the receive_buf path so single threaded. - */ - -static inline void n_tty_receive_break(struct tty_struct *tty) -{ - if (I_IGNBRK(tty)) - return; - if (I_BRKINT(tty)) { - isig(SIGINT, tty, 1); - return; - } - if (I_PARMRK(tty)) { - put_tty_queue('\377', tty); - put_tty_queue('\0', tty); - } - put_tty_queue('\0', tty); - wake_up_interruptible(&tty->read_wait); -} - -/** - * n_tty_receive_overrun - handle overrun reporting - * @tty: terminal - * - * Data arrived faster than we could process it. While the tty - * driver has flagged this the bits that were missed are gone - * forever. - * - * Called from the receive_buf path so single threaded. Does not - * need locking as num_overrun and overrun_time are function - * private. - */ - -static inline void n_tty_receive_overrun(struct tty_struct *tty) -{ - char buf[64]; - - tty->num_overrun++; - if (time_before(tty->overrun_time, jiffies - HZ) || - time_after(tty->overrun_time, jiffies)) { - printk(KERN_WARNING "%s: %d input overrun(s)\n", - tty_name(tty, buf), - tty->num_overrun); - tty->overrun_time = jiffies; - tty->num_overrun = 0; - } -} - -/** - * n_tty_receive_parity_error - error notifier - * @tty: terminal device - * @c: character - * - * Process a parity error and queue the right data to indicate - * the error case if necessary. Locking as per n_tty_receive_buf. - */ -static inline void n_tty_receive_parity_error(struct tty_struct *tty, - unsigned char c) -{ - if (I_IGNPAR(tty)) - return; - if (I_PARMRK(tty)) { - put_tty_queue('\377', tty); - put_tty_queue('\0', tty); - put_tty_queue(c, tty); - } else if (I_INPCK(tty)) - put_tty_queue('\0', tty); - else - put_tty_queue(c, tty); - wake_up_interruptible(&tty->read_wait); -} - -/** - * n_tty_receive_char - perform processing - * @tty: terminal device - * @c: character - * - * Process an individual character of input received from the driver. - * This is serialized with respect to itself by the rules for the - * driver above. - */ - -static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c) -{ - unsigned long flags; - int parmrk; - - if (tty->raw) { - put_tty_queue(c, tty); - return; - } - - if (I_ISTRIP(tty)) - c &= 0x7f; - if (I_IUCLC(tty) && L_IEXTEN(tty)) - c = tolower(c); - - if (L_EXTPROC(tty)) { - put_tty_queue(c, tty); - return; - } - - if (tty->stopped && !tty->flow_stopped && I_IXON(tty) && - I_IXANY(tty) && c != START_CHAR(tty) && c != STOP_CHAR(tty) && - c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) && c != SUSP_CHAR(tty)) { - start_tty(tty); - process_echoes(tty); - } - - if (tty->closing) { - if (I_IXON(tty)) { - if (c == START_CHAR(tty)) { - start_tty(tty); - process_echoes(tty); - } else if (c == STOP_CHAR(tty)) - stop_tty(tty); - } - return; - } - - /* - * If the previous character was LNEXT, or we know that this - * character is not one of the characters that we'll have to - * handle specially, do shortcut processing to speed things - * up. - */ - if (!test_bit(c, tty->process_char_map) || tty->lnext) { - tty->lnext = 0; - parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0; - if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk - 1)) { - /* beep if no space */ - if (L_ECHO(tty)) - process_output('\a', tty); - return; - } - if (L_ECHO(tty)) { - finish_erasing(tty); - /* Record the column of first canon char. */ - if (tty->canon_head == tty->read_head) - echo_set_canon_col(tty); - echo_char(c, tty); - process_echoes(tty); - } - if (parmrk) - put_tty_queue(c, tty); - put_tty_queue(c, tty); - return; - } - - if (I_IXON(tty)) { - if (c == START_CHAR(tty)) { - start_tty(tty); - process_echoes(tty); - return; - } - if (c == STOP_CHAR(tty)) { - stop_tty(tty); - return; - } - } - - if (L_ISIG(tty)) { - int signal; - signal = SIGINT; - if (c == INTR_CHAR(tty)) - goto send_signal; - signal = SIGQUIT; - if (c == QUIT_CHAR(tty)) - goto send_signal; - signal = SIGTSTP; - if (c == SUSP_CHAR(tty)) { -send_signal: - /* - * Note that we do not use isig() here because we want - * the order to be: - * 1) flush, 2) echo, 3) signal - */ - if (!L_NOFLSH(tty)) { - n_tty_flush_buffer(tty); - tty_driver_flush_buffer(tty); - } - if (I_IXON(tty)) - start_tty(tty); - if (L_ECHO(tty)) { - echo_char(c, tty); - process_echoes(tty); - } - if (tty->pgrp) - kill_pgrp(tty->pgrp, signal, 1); - return; - } - } - - if (c == '\r') { - if (I_IGNCR(tty)) - return; - if (I_ICRNL(tty)) - c = '\n'; - } else if (c == '\n' && I_INLCR(tty)) - c = '\r'; - - if (tty->icanon) { - if (c == ERASE_CHAR(tty) || c == KILL_CHAR(tty) || - (c == WERASE_CHAR(tty) && L_IEXTEN(tty))) { - eraser(c, tty); - process_echoes(tty); - return; - } - if (c == LNEXT_CHAR(tty) && L_IEXTEN(tty)) { - tty->lnext = 1; - if (L_ECHO(tty)) { - finish_erasing(tty); - if (L_ECHOCTL(tty)) { - echo_char_raw('^', tty); - echo_char_raw('\b', tty); - process_echoes(tty); - } - } - return; - } - if (c == REPRINT_CHAR(tty) && L_ECHO(tty) && - L_IEXTEN(tty)) { - unsigned long tail = tty->canon_head; - - finish_erasing(tty); - echo_char(c, tty); - echo_char_raw('\n', tty); - while (tail != tty->read_head) { - echo_char(tty->read_buf[tail], tty); - tail = (tail+1) & (N_TTY_BUF_SIZE-1); - } - process_echoes(tty); - return; - } - if (c == '\n') { - if (tty->read_cnt >= N_TTY_BUF_SIZE) { - if (L_ECHO(tty)) - process_output('\a', tty); - return; - } - if (L_ECHO(tty) || L_ECHONL(tty)) { - echo_char_raw('\n', tty); - process_echoes(tty); - } - goto handle_newline; - } - if (c == EOF_CHAR(tty)) { - if (tty->read_cnt >= N_TTY_BUF_SIZE) - return; - if (tty->canon_head != tty->read_head) - set_bit(TTY_PUSH, &tty->flags); - c = __DISABLED_CHAR; - goto handle_newline; - } - if ((c == EOL_CHAR(tty)) || - (c == EOL2_CHAR(tty) && L_IEXTEN(tty))) { - parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) - ? 1 : 0; - if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk)) { - if (L_ECHO(tty)) - process_output('\a', tty); - return; - } - /* - * XXX are EOL_CHAR and EOL2_CHAR echoed?!? - */ - if (L_ECHO(tty)) { - /* Record the column of first canon char. */ - if (tty->canon_head == tty->read_head) - echo_set_canon_col(tty); - echo_char(c, tty); - process_echoes(tty); - } - /* - * XXX does PARMRK doubling happen for - * EOL_CHAR and EOL2_CHAR? - */ - if (parmrk) - put_tty_queue(c, tty); - -handle_newline: - spin_lock_irqsave(&tty->read_lock, flags); - set_bit(tty->read_head, tty->read_flags); - put_tty_queue_nolock(c, tty); - tty->canon_head = tty->read_head; - tty->canon_data++; - spin_unlock_irqrestore(&tty->read_lock, flags); - kill_fasync(&tty->fasync, SIGIO, POLL_IN); - if (waitqueue_active(&tty->read_wait)) - wake_up_interruptible(&tty->read_wait); - return; - } - } - - parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0; - if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk - 1)) { - /* beep if no space */ - if (L_ECHO(tty)) - process_output('\a', tty); - return; - } - if (L_ECHO(tty)) { - finish_erasing(tty); - if (c == '\n') - echo_char_raw('\n', tty); - else { - /* Record the column of first canon char. */ - if (tty->canon_head == tty->read_head) - echo_set_canon_col(tty); - echo_char(c, tty); - } - process_echoes(tty); - } - - if (parmrk) - put_tty_queue(c, tty); - - put_tty_queue(c, tty); -} - - -/** - * n_tty_write_wakeup - asynchronous I/O notifier - * @tty: tty device - * - * Required for the ptys, serial driver etc. since processes - * that attach themselves to the master and rely on ASYNC - * IO must be woken up - */ - -static void n_tty_write_wakeup(struct tty_struct *tty) -{ - if (tty->fasync && test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) - kill_fasync(&tty->fasync, SIGIO, POLL_OUT); -} - -/** - * n_tty_receive_buf - data receive - * @tty: terminal device - * @cp: buffer - * @fp: flag buffer - * @count: characters - * - * Called by the terminal driver when a block of characters has - * been received. This function must be called from soft contexts - * not from interrupt context. The driver is responsible for making - * calls one at a time and in order (or using flush_to_ldisc) - */ - -static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) -{ - const unsigned char *p; - char *f, flags = TTY_NORMAL; - int i; - char buf[64]; - unsigned long cpuflags; - - if (!tty->read_buf) - return; - - if (tty->real_raw) { - spin_lock_irqsave(&tty->read_lock, cpuflags); - i = min(N_TTY_BUF_SIZE - tty->read_cnt, - N_TTY_BUF_SIZE - tty->read_head); - i = min(count, i); - memcpy(tty->read_buf + tty->read_head, cp, i); - tty->read_head = (tty->read_head + i) & (N_TTY_BUF_SIZE-1); - tty->read_cnt += i; - cp += i; - count -= i; - - i = min(N_TTY_BUF_SIZE - tty->read_cnt, - N_TTY_BUF_SIZE - tty->read_head); - i = min(count, i); - memcpy(tty->read_buf + tty->read_head, cp, i); - tty->read_head = (tty->read_head + i) & (N_TTY_BUF_SIZE-1); - tty->read_cnt += i; - spin_unlock_irqrestore(&tty->read_lock, cpuflags); - } else { - for (i = count, p = cp, f = fp; i; i--, p++) { - if (f) - flags = *f++; - switch (flags) { - case TTY_NORMAL: - n_tty_receive_char(tty, *p); - break; - case TTY_BREAK: - n_tty_receive_break(tty); - break; - case TTY_PARITY: - case TTY_FRAME: - n_tty_receive_parity_error(tty, *p); - break; - case TTY_OVERRUN: - n_tty_receive_overrun(tty); - break; - default: - printk(KERN_ERR "%s: unknown flag %d\n", - tty_name(tty, buf), flags); - break; - } - } - if (tty->ops->flush_chars) - tty->ops->flush_chars(tty); - } - - n_tty_set_room(tty); - - if ((!tty->icanon && (tty->read_cnt >= tty->minimum_to_wake)) || - L_EXTPROC(tty)) { - kill_fasync(&tty->fasync, SIGIO, POLL_IN); - if (waitqueue_active(&tty->read_wait)) - wake_up_interruptible(&tty->read_wait); - } - - /* - * Check the remaining room for the input canonicalization - * mode. We don't want to throttle the driver if we're in - * canonical mode and don't have a newline yet! - */ - if (tty->receive_room < TTY_THRESHOLD_THROTTLE) - tty_throttle(tty); -} - -int is_ignored(int sig) -{ - return (sigismember(¤t->blocked, sig) || - current->sighand->action[sig-1].sa.sa_handler == SIG_IGN); -} - -/** - * n_tty_set_termios - termios data changed - * @tty: terminal - * @old: previous data - * - * Called by the tty layer when the user changes termios flags so - * that the line discipline can plan ahead. This function cannot sleep - * and is protected from re-entry by the tty layer. The user is - * guaranteed that this function will not be re-entered or in progress - * when the ldisc is closed. - * - * Locking: Caller holds tty->termios_mutex - */ - -static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old) -{ - int canon_change = 1; - BUG_ON(!tty); - - if (old) - canon_change = (old->c_lflag ^ tty->termios->c_lflag) & ICANON; - if (canon_change) { - memset(&tty->read_flags, 0, sizeof tty->read_flags); - tty->canon_head = tty->read_tail; - tty->canon_data = 0; - tty->erasing = 0; - } - - if (canon_change && !L_ICANON(tty) && tty->read_cnt) - wake_up_interruptible(&tty->read_wait); - - tty->icanon = (L_ICANON(tty) != 0); - if (test_bit(TTY_HW_COOK_IN, &tty->flags)) { - tty->raw = 1; - tty->real_raw = 1; - n_tty_set_room(tty); - return; - } - if (I_ISTRIP(tty) || I_IUCLC(tty) || I_IGNCR(tty) || - I_ICRNL(tty) || I_INLCR(tty) || L_ICANON(tty) || - I_IXON(tty) || L_ISIG(tty) || L_ECHO(tty) || - I_PARMRK(tty)) { - memset(tty->process_char_map, 0, 256/8); - - if (I_IGNCR(tty) || I_ICRNL(tty)) - set_bit('\r', tty->process_char_map); - if (I_INLCR(tty)) - set_bit('\n', tty->process_char_map); - - if (L_ICANON(tty)) { - set_bit(ERASE_CHAR(tty), tty->process_char_map); - set_bit(KILL_CHAR(tty), tty->process_char_map); - set_bit(EOF_CHAR(tty), tty->process_char_map); - set_bit('\n', tty->process_char_map); - set_bit(EOL_CHAR(tty), tty->process_char_map); - if (L_IEXTEN(tty)) { - set_bit(WERASE_CHAR(tty), - tty->process_char_map); - set_bit(LNEXT_CHAR(tty), - tty->process_char_map); - set_bit(EOL2_CHAR(tty), - tty->process_char_map); - if (L_ECHO(tty)) - set_bit(REPRINT_CHAR(tty), - tty->process_char_map); - } - } - if (I_IXON(tty)) { - set_bit(START_CHAR(tty), tty->process_char_map); - set_bit(STOP_CHAR(tty), tty->process_char_map); - } - if (L_ISIG(tty)) { - set_bit(INTR_CHAR(tty), tty->process_char_map); - set_bit(QUIT_CHAR(tty), tty->process_char_map); - set_bit(SUSP_CHAR(tty), tty->process_char_map); - } - clear_bit(__DISABLED_CHAR, tty->process_char_map); - tty->raw = 0; - tty->real_raw = 0; - } else { - tty->raw = 1; - if ((I_IGNBRK(tty) || (!I_BRKINT(tty) && !I_PARMRK(tty))) && - (I_IGNPAR(tty) || !I_INPCK(tty)) && - (tty->driver->flags & TTY_DRIVER_REAL_RAW)) - tty->real_raw = 1; - else - tty->real_raw = 0; - } - n_tty_set_room(tty); - /* The termios change make the tty ready for I/O */ - wake_up_interruptible(&tty->write_wait); - wake_up_interruptible(&tty->read_wait); -} - -/** - * n_tty_close - close the ldisc for this tty - * @tty: device - * - * Called from the terminal layer when this line discipline is - * being shut down, either because of a close or becsuse of a - * discipline change. The function will not be called while other - * ldisc methods are in progress. - */ - -static void n_tty_close(struct tty_struct *tty) -{ - n_tty_flush_buffer(tty); - if (tty->read_buf) { - kfree(tty->read_buf); - tty->read_buf = NULL; - } - if (tty->echo_buf) { - kfree(tty->echo_buf); - tty->echo_buf = NULL; - } -} - -/** - * n_tty_open - open an ldisc - * @tty: terminal to open - * - * Called when this line discipline is being attached to the - * terminal device. Can sleep. Called serialized so that no - * other events will occur in parallel. No further open will occur - * until a close. - */ - -static int n_tty_open(struct tty_struct *tty) -{ - if (!tty) - return -EINVAL; - - /* These are ugly. Currently a malloc failure here can panic */ - if (!tty->read_buf) { - tty->read_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL); - if (!tty->read_buf) - return -ENOMEM; - } - if (!tty->echo_buf) { - tty->echo_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL); - - if (!tty->echo_buf) - return -ENOMEM; - } - reset_buffer_flags(tty); - tty->column = 0; - n_tty_set_termios(tty, NULL); - tty->minimum_to_wake = 1; - tty->closing = 0; - return 0; -} - -static inline int input_available_p(struct tty_struct *tty, int amt) -{ - tty_flush_to_ldisc(tty); - if (tty->icanon && !L_EXTPROC(tty)) { - if (tty->canon_data) - return 1; - } else if (tty->read_cnt >= (amt ? amt : 1)) - return 1; - - return 0; -} - -/** - * copy_from_read_buf - copy read data directly - * @tty: terminal device - * @b: user data - * @nr: size of data - * - * Helper function to speed up n_tty_read. It is only called when - * ICANON is off; it copies characters straight from the tty queue to - * user space directly. It can be profitably called twice; once to - * drain the space from the tail pointer to the (physical) end of the - * buffer, and once to drain the space from the (physical) beginning of - * the buffer to head pointer. - * - * Called under the tty->atomic_read_lock sem - * - */ - -static int copy_from_read_buf(struct tty_struct *tty, - unsigned char __user **b, - size_t *nr) - -{ - int retval; - size_t n; - unsigned long flags; - - retval = 0; - spin_lock_irqsave(&tty->read_lock, flags); - n = min(tty->read_cnt, N_TTY_BUF_SIZE - tty->read_tail); - n = min(*nr, n); - spin_unlock_irqrestore(&tty->read_lock, flags); - if (n) { - retval = copy_to_user(*b, &tty->read_buf[tty->read_tail], n); - n -= retval; - tty_audit_add_data(tty, &tty->read_buf[tty->read_tail], n); - spin_lock_irqsave(&tty->read_lock, flags); - tty->read_tail = (tty->read_tail + n) & (N_TTY_BUF_SIZE-1); - tty->read_cnt -= n; - /* Turn single EOF into zero-length read */ - if (L_EXTPROC(tty) && tty->icanon && n == 1) { - if (!tty->read_cnt && (*b)[n-1] == EOF_CHAR(tty)) - n--; - } - spin_unlock_irqrestore(&tty->read_lock, flags); - *b += n; - *nr -= n; - } - return retval; -} - -extern ssize_t redirected_tty_write(struct file *, const char __user *, - size_t, loff_t *); - -/** - * job_control - check job control - * @tty: tty - * @file: file handle - * - * Perform job control management checks on this file/tty descriptor - * and if appropriate send any needed signals and return a negative - * error code if action should be taken. - * - * FIXME: - * Locking: None - redirected write test is safe, testing - * current->signal should possibly lock current->sighand - * pgrp locking ? - */ - -static int job_control(struct tty_struct *tty, struct file *file) -{ - /* Job control check -- must be done at start and after - every sleep (POSIX.1 7.1.1.4). */ - /* NOTE: not yet done after every sleep pending a thorough - check of the logic of this change. -- jlc */ - /* don't stop on /dev/console */ - if (file->f_op->write != redirected_tty_write && - current->signal->tty == tty) { - if (!tty->pgrp) - printk(KERN_ERR "n_tty_read: no tty->pgrp!\n"); - else if (task_pgrp(current) != tty->pgrp) { - if (is_ignored(SIGTTIN) || - is_current_pgrp_orphaned()) - return -EIO; - kill_pgrp(task_pgrp(current), SIGTTIN, 1); - set_thread_flag(TIF_SIGPENDING); - return -ERESTARTSYS; - } - } - return 0; -} - - -/** - * n_tty_read - read function for tty - * @tty: tty device - * @file: file object - * @buf: userspace buffer pointer - * @nr: size of I/O - * - * Perform reads for the line discipline. We are guaranteed that the - * line discipline will not be closed under us but we may get multiple - * parallel readers and must handle this ourselves. We may also get - * a hangup. Always called in user context, may sleep. - * - * This code must be sure never to sleep through a hangup. - */ - -static ssize_t n_tty_read(struct tty_struct *tty, struct file *file, - unsigned char __user *buf, size_t nr) -{ - unsigned char __user *b = buf; - DECLARE_WAITQUEUE(wait, current); - int c; - int minimum, time; - ssize_t retval = 0; - ssize_t size; - long timeout; - unsigned long flags; - int packet; - -do_it_again: - - BUG_ON(!tty->read_buf); - - c = job_control(tty, file); - if (c < 0) - return c; - - minimum = time = 0; - timeout = MAX_SCHEDULE_TIMEOUT; - if (!tty->icanon) { - time = (HZ / 10) * TIME_CHAR(tty); - minimum = MIN_CHAR(tty); - if (minimum) { - if (time) - tty->minimum_to_wake = 1; - else if (!waitqueue_active(&tty->read_wait) || - (tty->minimum_to_wake > minimum)) - tty->minimum_to_wake = minimum; - } else { - timeout = 0; - if (time) { - timeout = time; - time = 0; - } - tty->minimum_to_wake = minimum = 1; - } - } - - /* - * Internal serialization of reads. - */ - if (file->f_flags & O_NONBLOCK) { - if (!mutex_trylock(&tty->atomic_read_lock)) - return -EAGAIN; - } else { - if (mutex_lock_interruptible(&tty->atomic_read_lock)) - return -ERESTARTSYS; - } - packet = tty->packet; - - add_wait_queue(&tty->read_wait, &wait); - while (nr) { - /* First test for status change. */ - if (packet && tty->link->ctrl_status) { - unsigned char cs; - if (b != buf) - break; - spin_lock_irqsave(&tty->link->ctrl_lock, flags); - cs = tty->link->ctrl_status; - tty->link->ctrl_status = 0; - spin_unlock_irqrestore(&tty->link->ctrl_lock, flags); - if (tty_put_user(tty, cs, b++)) { - retval = -EFAULT; - b--; - break; - } - nr--; - break; - } - /* This statement must be first before checking for input - so that any interrupt will set the state back to - TASK_RUNNING. */ - set_current_state(TASK_INTERRUPTIBLE); - - if (((minimum - (b - buf)) < tty->minimum_to_wake) && - ((minimum - (b - buf)) >= 1)) - tty->minimum_to_wake = (minimum - (b - buf)); - - if (!input_available_p(tty, 0)) { - if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) { - retval = -EIO; - break; - } - if (tty_hung_up_p(file)) - break; - if (!timeout) - break; - if (file->f_flags & O_NONBLOCK) { - retval = -EAGAIN; - break; - } - if (signal_pending(current)) { - retval = -ERESTARTSYS; - break; - } - /* FIXME: does n_tty_set_room need locking ? */ - n_tty_set_room(tty); - timeout = schedule_timeout(timeout); - continue; - } - __set_current_state(TASK_RUNNING); - - /* Deal with packet mode. */ - if (packet && b == buf) { - if (tty_put_user(tty, TIOCPKT_DATA, b++)) { - retval = -EFAULT; - b--; - break; - } - nr--; - } - - if (tty->icanon && !L_EXTPROC(tty)) { - /* N.B. avoid overrun if nr == 0 */ - while (nr && tty->read_cnt) { - int eol; - - eol = test_and_clear_bit(tty->read_tail, - tty->read_flags); - c = tty->read_buf[tty->read_tail]; - spin_lock_irqsave(&tty->read_lock, flags); - tty->read_tail = ((tty->read_tail+1) & - (N_TTY_BUF_SIZE-1)); - tty->read_cnt--; - if (eol) { - /* this test should be redundant: - * we shouldn't be reading data if - * canon_data is 0 - */ - if (--tty->canon_data < 0) - tty->canon_data = 0; - } - spin_unlock_irqrestore(&tty->read_lock, flags); - - if (!eol || (c != __DISABLED_CHAR)) { - if (tty_put_user(tty, c, b++)) { - retval = -EFAULT; - b--; - break; - } - nr--; - } - if (eol) { - tty_audit_push(tty); - break; - } - } - if (retval) - break; - } else { - int uncopied; - /* The copy function takes the read lock and handles - locking internally for this case */ - uncopied = copy_from_read_buf(tty, &b, &nr); - uncopied += copy_from_read_buf(tty, &b, &nr); - if (uncopied) { - retval = -EFAULT; - break; - } - } - - /* If there is enough space in the read buffer now, let the - * low-level driver know. We use n_tty_chars_in_buffer() to - * check the buffer, as it now knows about canonical mode. - * Otherwise, if the driver is throttled and the line is - * longer than TTY_THRESHOLD_UNTHROTTLE in canonical mode, - * we won't get any more characters. - */ - if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE) { - n_tty_set_room(tty); - check_unthrottle(tty); - } - - if (b - buf >= minimum) - break; - if (time) - timeout = time; - } - mutex_unlock(&tty->atomic_read_lock); - remove_wait_queue(&tty->read_wait, &wait); - - if (!waitqueue_active(&tty->read_wait)) - tty->minimum_to_wake = minimum; - - __set_current_state(TASK_RUNNING); - size = b - buf; - if (size) { - retval = size; - if (nr) - clear_bit(TTY_PUSH, &tty->flags); - } else if (test_and_clear_bit(TTY_PUSH, &tty->flags)) - goto do_it_again; - - n_tty_set_room(tty); - return retval; -} - -/** - * n_tty_write - write function for tty - * @tty: tty device - * @file: file object - * @buf: userspace buffer pointer - * @nr: size of I/O - * - * Write function of the terminal device. This is serialized with - * respect to other write callers but not to termios changes, reads - * and other such events. Since the receive code will echo characters, - * thus calling driver write methods, the output_lock is used in - * the output processing functions called here as well as in the - * echo processing function to protect the column state and space - * left in the buffer. - * - * This code must be sure never to sleep through a hangup. - * - * Locking: output_lock to protect column state and space left - * (note that the process_output*() functions take this - * lock themselves) - */ - -static ssize_t n_tty_write(struct tty_struct *tty, struct file *file, - const unsigned char *buf, size_t nr) -{ - const unsigned char *b = buf; - DECLARE_WAITQUEUE(wait, current); - int c; - ssize_t retval = 0; - - /* Job control check -- must be done at start (POSIX.1 7.1.1.4). */ - if (L_TOSTOP(tty) && file->f_op->write != redirected_tty_write) { - retval = tty_check_change(tty); - if (retval) - return retval; - } - - /* Write out any echoed characters that are still pending */ - process_echoes(tty); - - add_wait_queue(&tty->write_wait, &wait); - while (1) { - set_current_state(TASK_INTERRUPTIBLE); - if (signal_pending(current)) { - retval = -ERESTARTSYS; - break; - } - if (tty_hung_up_p(file) || (tty->link && !tty->link->count)) { - retval = -EIO; - break; - } - if (O_OPOST(tty) && !(test_bit(TTY_HW_COOK_OUT, &tty->flags))) { - while (nr > 0) { - ssize_t num = process_output_block(tty, b, nr); - if (num < 0) { - if (num == -EAGAIN) - break; - retval = num; - goto break_out; - } - b += num; - nr -= num; - if (nr == 0) - break; - c = *b; - if (process_output(c, tty) < 0) - break; - b++; nr--; - } - if (tty->ops->flush_chars) - tty->ops->flush_chars(tty); - } else { - while (nr > 0) { - c = tty->ops->write(tty, b, nr); - if (c < 0) { - retval = c; - goto break_out; - } - if (!c) - break; - b += c; - nr -= c; - } - } - if (!nr) - break; - if (file->f_flags & O_NONBLOCK) { - retval = -EAGAIN; - break; - } - schedule(); - } -break_out: - __set_current_state(TASK_RUNNING); - remove_wait_queue(&tty->write_wait, &wait); - if (b - buf != nr && tty->fasync) - set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); - return (b - buf) ? b - buf : retval; -} - -/** - * n_tty_poll - poll method for N_TTY - * @tty: terminal device - * @file: file accessing it - * @wait: poll table - * - * Called when the line discipline is asked to poll() for data or - * for special events. This code is not serialized with respect to - * other events save open/close. - * - * This code must be sure never to sleep through a hangup. - * Called without the kernel lock held - fine - */ - -static unsigned int n_tty_poll(struct tty_struct *tty, struct file *file, - poll_table *wait) -{ - unsigned int mask = 0; - - poll_wait(file, &tty->read_wait, wait); - poll_wait(file, &tty->write_wait, wait); - if (input_available_p(tty, TIME_CHAR(tty) ? 0 : MIN_CHAR(tty))) - mask |= POLLIN | POLLRDNORM; - if (tty->packet && tty->link->ctrl_status) - mask |= POLLPRI | POLLIN | POLLRDNORM; - if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) - mask |= POLLHUP; - if (tty_hung_up_p(file)) - mask |= POLLHUP; - if (!(mask & (POLLHUP | POLLIN | POLLRDNORM))) { - if (MIN_CHAR(tty) && !TIME_CHAR(tty)) - tty->minimum_to_wake = MIN_CHAR(tty); - else - tty->minimum_to_wake = 1; - } - if (tty->ops->write && !tty_is_writelocked(tty) && - tty_chars_in_buffer(tty) < WAKEUP_CHARS && - tty_write_room(tty) > 0) - mask |= POLLOUT | POLLWRNORM; - return mask; -} - -static unsigned long inq_canon(struct tty_struct *tty) -{ - int nr, head, tail; - - if (!tty->canon_data) - return 0; - head = tty->canon_head; - tail = tty->read_tail; - nr = (head - tail) & (N_TTY_BUF_SIZE-1); - /* Skip EOF-chars.. */ - while (head != tail) { - if (test_bit(tail, tty->read_flags) && - tty->read_buf[tail] == __DISABLED_CHAR) - nr--; - tail = (tail+1) & (N_TTY_BUF_SIZE-1); - } - return nr; -} - -static int n_tty_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - int retval; - - switch (cmd) { - case TIOCOUTQ: - return put_user(tty_chars_in_buffer(tty), (int __user *) arg); - case TIOCINQ: - /* FIXME: Locking */ - retval = tty->read_cnt; - if (L_ICANON(tty)) - retval = inq_canon(tty); - return put_user(retval, (unsigned int __user *) arg); - default: - return n_tty_ioctl_helper(tty, file, cmd, arg); - } -} - -struct tty_ldisc_ops tty_ldisc_N_TTY = { - .magic = TTY_LDISC_MAGIC, - .name = "n_tty", - .open = n_tty_open, - .close = n_tty_close, - .flush_buffer = n_tty_flush_buffer, - .chars_in_buffer = n_tty_chars_in_buffer, - .read = n_tty_read, - .write = n_tty_write, - .ioctl = n_tty_ioctl, - .set_termios = n_tty_set_termios, - .poll = n_tty_poll, - .receive_buf = n_tty_receive_buf, - .write_wakeup = n_tty_write_wakeup -}; - -/** - * n_tty_inherit_ops - inherit N_TTY methods - * @ops: struct tty_ldisc_ops where to save N_TTY methods - * - * Used by a generic struct tty_ldisc_ops to easily inherit N_TTY - * methods. - */ - -void n_tty_inherit_ops(struct tty_ldisc_ops *ops) -{ - *ops = tty_ldisc_N_TTY; - ops->owner = NULL; - ops->refcount = ops->flags = 0; -} -EXPORT_SYMBOL_GPL(n_tty_inherit_ops); diff --git a/drivers/char/pty.c b/drivers/char/pty.c deleted file mode 100644 index 923a485..0000000 --- a/drivers/char/pty.c +++ /dev/null @@ -1,777 +0,0 @@ -/* - * linux/drivers/char/pty.c - * - * Copyright (C) 1991, 1992 Linus Torvalds - * - * Added support for a Unix98-style ptmx device. - * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998 - * - * When reading this code see also fs/devpts. In particular note that the - * driver_data field is used by the devpts side as a binding to the devpts - * inode. - */ - -#include <linux/module.h> - -#include <linux/errno.h> -#include <linux/interrupt.h> -#include <linux/tty.h> -#include <linux/tty_flip.h> -#include <linux/fcntl.h> -#include <linux/sched.h> -#include <linux/string.h> -#include <linux/major.h> -#include <linux/mm.h> -#include <linux/init.h> -#include <linux/smp_lock.h> -#include <linux/sysctl.h> -#include <linux/device.h> -#include <linux/uaccess.h> -#include <linux/bitops.h> -#include <linux/devpts_fs.h> -#include <linux/slab.h> - -#include <asm/system.h> - -#ifdef CONFIG_UNIX98_PTYS -static struct tty_driver *ptm_driver; -static struct tty_driver *pts_driver; -#endif - -static void pty_close(struct tty_struct *tty, struct file *filp) -{ - BUG_ON(!tty); - if (tty->driver->subtype == PTY_TYPE_MASTER) - WARN_ON(tty->count > 1); - else { - if (tty->count > 2) - return; - } - wake_up_interruptible(&tty->read_wait); - wake_up_interruptible(&tty->write_wait); - tty->packet = 0; - if (!tty->link) - return; - tty->link->packet = 0; - set_bit(TTY_OTHER_CLOSED, &tty->link->flags); - wake_up_interruptible(&tty->link->read_wait); - wake_up_interruptible(&tty->link->write_wait); - if (tty->driver->subtype == PTY_TYPE_MASTER) { - set_bit(TTY_OTHER_CLOSED, &tty->flags); -#ifdef CONFIG_UNIX98_PTYS - if (tty->driver == ptm_driver) - devpts_pty_kill(tty->link); -#endif - tty_unlock(); - tty_vhangup(tty->link); - tty_lock(); - } -} - -/* - * The unthrottle routine is called by the line discipline to signal - * that it can receive more characters. For PTY's, the TTY_THROTTLED - * flag is always set, to force the line discipline to always call the - * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE - * characters in the queue. This is necessary since each time this - * happens, we need to wake up any sleeping processes that could be - * (1) trying to send data to the pty, or (2) waiting in wait_until_sent() - * for the pty buffer to be drained. - */ -static void pty_unthrottle(struct tty_struct *tty) -{ - tty_wakeup(tty->link); - set_bit(TTY_THROTTLED, &tty->flags); -} - -/** - * pty_space - report space left for writing - * @to: tty we are writing into - * - * The tty buffers allow 64K but we sneak a peak and clip at 8K this - * allows a lot of overspill room for echo and other fun messes to - * be handled properly - */ - -static int pty_space(struct tty_struct *to) -{ - int n = 8192 - to->buf.memory_used; - if (n < 0) - return 0; - return n; -} - -/** - * pty_write - write to a pty - * @tty: the tty we write from - * @buf: kernel buffer of data - * @count: bytes to write - * - * Our "hardware" write method. Data is coming from the ldisc which - * may be in a non sleeping state. We simply throw this at the other - * end of the link as if we were an IRQ handler receiving stuff for - * the other side of the pty/tty pair. - */ - -static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c) -{ - struct tty_struct *to = tty->link; - - if (tty->stopped) - return 0; - - if (c > 0) { - /* Stuff the data into the input queue of the other end */ - c = tty_insert_flip_string(to, buf, c); - /* And shovel */ - if (c) { - tty_flip_buffer_push(to); - tty_wakeup(tty); - } - } - return c; -} - -/** - * pty_write_room - write space - * @tty: tty we are writing from - * - * Report how many bytes the ldisc can send into the queue for - * the other device. - */ - -static int pty_write_room(struct tty_struct *tty) -{ - if (tty->stopped) - return 0; - return pty_space(tty->link); -} - -/** - * pty_chars_in_buffer - characters currently in our tx queue - * @tty: our tty - * - * Report how much we have in the transmit queue. As everything is - * instantly at the other end this is easy to implement. - */ - -static int pty_chars_in_buffer(struct tty_struct *tty) -{ - return 0; -} - -/* Set the lock flag on a pty */ -static int pty_set_lock(struct tty_struct *tty, int __user *arg) -{ - int val; - if (get_user(val, arg)) - return -EFAULT; - if (val) - set_bit(TTY_PTY_LOCK, &tty->flags); - else - clear_bit(TTY_PTY_LOCK, &tty->flags); - return 0; -} - -/* Send a signal to the slave */ -static int pty_signal(struct tty_struct *tty, int sig) -{ - unsigned long flags; - struct pid *pgrp; - - if (tty->link) { - spin_lock_irqsave(&tty->link->ctrl_lock, flags); - pgrp = get_pid(tty->link->pgrp); - spin_unlock_irqrestore(&tty->link->ctrl_lock, flags); - - kill_pgrp(pgrp, sig, 1); - put_pid(pgrp); - } - return 0; -} - -static void pty_flush_buffer(struct tty_struct *tty) -{ - struct tty_struct *to = tty->link; - unsigned long flags; - - if (!to) - return; - /* tty_buffer_flush(to); FIXME */ - if (to->packet) { - spin_lock_irqsave(&tty->ctrl_lock, flags); - tty->ctrl_status |= TIOCPKT_FLUSHWRITE; - wake_up_interruptible(&to->read_wait); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - } -} - -static int pty_open(struct tty_struct *tty, struct file *filp) -{ - int retval = -ENODEV; - - if (!tty || !tty->link) - goto out; - - retval = -EIO; - if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) - goto out; - if (test_bit(TTY_PTY_LOCK, &tty->link->flags)) - goto out; - if (tty->link->count != 1) - goto out; - - clear_bit(TTY_OTHER_CLOSED, &tty->link->flags); - set_bit(TTY_THROTTLED, &tty->flags); - retval = 0; -out: - return retval; -} - -static void pty_set_termios(struct tty_struct *tty, - struct ktermios *old_termios) -{ - tty->termios->c_cflag &= ~(CSIZE | PARENB); - tty->termios->c_cflag |= (CS8 | CREAD); -} - -/** - * pty_do_resize - resize event - * @tty: tty being resized - * @ws: window size being set. - * - * Update the termios variables and send the necessary signals to - * peform a terminal resize correctly - */ - -int pty_resize(struct tty_struct *tty, struct winsize *ws) -{ - struct pid *pgrp, *rpgrp; - unsigned long flags; - struct tty_struct *pty = tty->link; - - /* For a PTY we need to lock the tty side */ - mutex_lock(&tty->termios_mutex); - if (!memcmp(ws, &tty->winsize, sizeof(*ws))) - goto done; - - /* Get the PID values and reference them so we can - avoid holding the tty ctrl lock while sending signals. - We need to lock these individually however. */ - - spin_lock_irqsave(&tty->ctrl_lock, flags); - pgrp = get_pid(tty->pgrp); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - - spin_lock_irqsave(&pty->ctrl_lock, flags); - rpgrp = get_pid(pty->pgrp); - spin_unlock_irqrestore(&pty->ctrl_lock, flags); - - if (pgrp) - kill_pgrp(pgrp, SIGWINCH, 1); - if (rpgrp != pgrp && rpgrp) - kill_pgrp(rpgrp, SIGWINCH, 1); - - put_pid(pgrp); - put_pid(rpgrp); - - tty->winsize = *ws; - pty->winsize = *ws; /* Never used so will go away soon */ -done: - mutex_unlock(&tty->termios_mutex); - return 0; -} - -/* Traditional BSD devices */ -#ifdef CONFIG_LEGACY_PTYS - -static int pty_install(struct tty_driver *driver, struct tty_struct *tty) -{ - struct tty_struct *o_tty; - int idx = tty->index; - int retval; - - o_tty = alloc_tty_struct(); - if (!o_tty) - return -ENOMEM; - if (!try_module_get(driver->other->owner)) { - /* This cannot in fact currently happen */ - free_tty_struct(o_tty); - return -ENOMEM; - } - initialize_tty_struct(o_tty, driver->other, idx); - - /* We always use new tty termios data so we can do this - the easy way .. */ - retval = tty_init_termios(tty); - if (retval) - goto free_mem_out; - - retval = tty_init_termios(o_tty); - if (retval) { - tty_free_termios(tty); - goto free_mem_out; - } - - /* - * Everything allocated ... set up the o_tty structure. - */ - driver->other->ttys[idx] = o_tty; - tty_driver_kref_get(driver->other); - if (driver->subtype == PTY_TYPE_MASTER) - o_tty->count++; - /* Establish the links in both directions */ - tty->link = o_tty; - o_tty->link = tty; - - tty_driver_kref_get(driver); - tty->count++; - driver->ttys[idx] = tty; - return 0; -free_mem_out: - module_put(o_tty->driver->owner); - free_tty_struct(o_tty); - return -ENOMEM; -} - -static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - switch (cmd) { - case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ - return pty_set_lock(tty, (int __user *) arg); - case TIOCSIG: /* Send signal to other side of pty */ - return pty_signal(tty, (int) arg); - } - return -ENOIOCTLCMD; -} - -static int legacy_count = CONFIG_LEGACY_PTY_COUNT; -module_param(legacy_count, int, 0); - -/* - * The master side of a pty can do TIOCSPTLCK and thus - * has pty_bsd_ioctl. - */ -static const struct tty_operations master_pty_ops_bsd = { - .install = pty_install, - .open = pty_open, - .close = pty_close, - .write = pty_write, - .write_room = pty_write_room, - .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, - .unthrottle = pty_unthrottle, - .set_termios = pty_set_termios, - .ioctl = pty_bsd_ioctl, - .resize = pty_resize -}; - -static const struct tty_operations slave_pty_ops_bsd = { - .install = pty_install, - .open = pty_open, - .close = pty_close, - .write = pty_write, - .write_room = pty_write_room, - .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, - .unthrottle = pty_unthrottle, - .set_termios = pty_set_termios, - .resize = pty_resize -}; - -static void __init legacy_pty_init(void) -{ - struct tty_driver *pty_driver, *pty_slave_driver; - - if (legacy_count <= 0) - return; - - pty_driver = alloc_tty_driver(legacy_count); - if (!pty_driver) - panic("Couldn't allocate pty driver"); - - pty_slave_driver = alloc_tty_driver(legacy_count); - if (!pty_slave_driver) - panic("Couldn't allocate pty slave driver"); - - pty_driver->owner = THIS_MODULE; - pty_driver->driver_name = "pty_master"; - pty_driver->name = "pty"; - pty_driver->major = PTY_MASTER_MAJOR; - pty_driver->minor_start = 0; - pty_driver->type = TTY_DRIVER_TYPE_PTY; - pty_driver->subtype = PTY_TYPE_MASTER; - pty_driver->init_termios = tty_std_termios; - pty_driver->init_termios.c_iflag = 0; - pty_driver->init_termios.c_oflag = 0; - pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; - pty_driver->init_termios.c_lflag = 0; - pty_driver->init_termios.c_ispeed = 38400; - pty_driver->init_termios.c_ospeed = 38400; - pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW; - pty_driver->other = pty_slave_driver; - tty_set_operations(pty_driver, &master_pty_ops_bsd); - - pty_slave_driver->owner = THIS_MODULE; - pty_slave_driver->driver_name = "pty_slave"; - pty_slave_driver->name = "ttyp"; - pty_slave_driver->major = PTY_SLAVE_MAJOR; - pty_slave_driver->minor_start = 0; - pty_slave_driver->type = TTY_DRIVER_TYPE_PTY; - pty_slave_driver->subtype = PTY_TYPE_SLAVE; - pty_slave_driver->init_termios = tty_std_termios; - pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; - pty_slave_driver->init_termios.c_ispeed = 38400; - pty_slave_driver->init_termios.c_ospeed = 38400; - pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS | - TTY_DRIVER_REAL_RAW; - pty_slave_driver->other = pty_driver; - tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); - - if (tty_register_driver(pty_driver)) - panic("Couldn't register pty driver"); - if (tty_register_driver(pty_slave_driver)) - panic("Couldn't register pty slave driver"); -} -#else -static inline void legacy_pty_init(void) { } -#endif - -/* Unix98 devices */ -#ifdef CONFIG_UNIX98_PTYS -/* - * sysctl support for setting limits on the number of Unix98 ptys allocated. - * Otherwise one can eat up all kernel memory by opening /dev/ptmx repeatedly. - */ -int pty_limit = NR_UNIX98_PTY_DEFAULT; -static int pty_limit_min; -static int pty_limit_max = NR_UNIX98_PTY_MAX; -static int pty_count; - -static struct cdev ptmx_cdev; - -static struct ctl_table pty_table[] = { - { - .procname = "max", - .maxlen = sizeof(int), - .mode = 0644, - .data = &pty_limit, - .proc_handler = proc_dointvec_minmax, - .extra1 = &pty_limit_min, - .extra2 = &pty_limit_max, - }, { - .procname = "nr", - .maxlen = sizeof(int), - .mode = 0444, - .data = &pty_count, - .proc_handler = proc_dointvec, - }, - {} -}; - -static struct ctl_table pty_kern_table[] = { - { - .procname = "pty", - .mode = 0555, - .child = pty_table, - }, - {} -}; - -static struct ctl_table pty_root_table[] = { - { - .procname = "kernel", - .mode = 0555, - .child = pty_kern_table, - }, - {} -}; - - -static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - switch (cmd) { - case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ - return pty_set_lock(tty, (int __user *)arg); - case TIOCGPTN: /* Get PT Number */ - return put_user(tty->index, (unsigned int __user *)arg); - case TIOCSIG: /* Send signal to other side of pty */ - return pty_signal(tty, (int) arg); - } - - return -ENOIOCTLCMD; -} - -/** - * ptm_unix98_lookup - find a pty master - * @driver: ptm driver - * @idx: tty index - * - * Look up a pty master device. Called under the tty_mutex for now. - * This provides our locking. - */ - -static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver, - struct inode *ptm_inode, int idx) -{ - struct tty_struct *tty = devpts_get_tty(ptm_inode, idx); - if (tty) - tty = tty->link; - return tty; -} - -/** - * pts_unix98_lookup - find a pty slave - * @driver: pts driver - * @idx: tty index - * - * Look up a pty master device. Called under the tty_mutex for now. - * This provides our locking. - */ - -static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, - struct inode *pts_inode, int idx) -{ - struct tty_struct *tty = devpts_get_tty(pts_inode, idx); - /* Master must be open before slave */ - if (!tty) - return ERR_PTR(-EIO); - return tty; -} - -static void pty_unix98_shutdown(struct tty_struct *tty) -{ - /* We have our own method as we don't use the tty index */ - kfree(tty->termios); -} - -/* We have no need to install and remove our tty objects as devpts does all - the work for us */ - -static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) -{ - struct tty_struct *o_tty; - int idx = tty->index; - - o_tty = alloc_tty_struct(); - if (!o_tty) - return -ENOMEM; - if (!try_module_get(driver->other->owner)) { - /* This cannot in fact currently happen */ - free_tty_struct(o_tty); - return -ENOMEM; - } - initialize_tty_struct(o_tty, driver->other, idx); - - tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL); - if (tty->termios == NULL) - goto free_mem_out; - *tty->termios = driver->init_termios; - tty->termios_locked = tty->termios + 1; - - o_tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL); - if (o_tty->termios == NULL) - goto free_mem_out; - *o_tty->termios = driver->other->init_termios; - o_tty->termios_locked = o_tty->termios + 1; - - tty_driver_kref_get(driver->other); - if (driver->subtype == PTY_TYPE_MASTER) - o_tty->count++; - /* Establish the links in both directions */ - tty->link = o_tty; - o_tty->link = tty; - /* - * All structures have been allocated, so now we install them. - * Failures after this point use release_tty to clean up, so - * there's no need to null out the local pointers. - */ - tty_driver_kref_get(driver); - tty->count++; - pty_count++; - return 0; -free_mem_out: - kfree(o_tty->termios); - module_put(o_tty->driver->owner); - free_tty_struct(o_tty); - kfree(tty->termios); - return -ENOMEM; -} - -static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty) -{ - pty_count--; -} - -static const struct tty_operations ptm_unix98_ops = { - .lookup = ptm_unix98_lookup, - .install = pty_unix98_install, - .remove = pty_unix98_remove, - .open = pty_open, - .close = pty_close, - .write = pty_write, - .write_room = pty_write_room, - .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, - .unthrottle = pty_unthrottle, - .set_termios = pty_set_termios, - .ioctl = pty_unix98_ioctl, - .shutdown = pty_unix98_shutdown, - .resize = pty_resize -}; - -static const struct tty_operations pty_unix98_ops = { - .lookup = pts_unix98_lookup, - .install = pty_unix98_install, - .remove = pty_unix98_remove, - .open = pty_open, - .close = pty_close, - .write = pty_write, - .write_room = pty_write_room, - .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, - .unthrottle = pty_unthrottle, - .set_termios = pty_set_termios, - .shutdown = pty_unix98_shutdown -}; - -/** - * ptmx_open - open a unix 98 pty master - * @inode: inode of device file - * @filp: file pointer to tty - * - * Allocate a unix98 pty master device from the ptmx driver. - * - * Locking: tty_mutex protects the init_dev work. tty->count should - * protect the rest. - * allocated_ptys_lock handles the list of free pty numbers - */ - -static int ptmx_open(struct inode *inode, struct file *filp) -{ - struct tty_struct *tty; - int retval; - int index; - - nonseekable_open(inode, filp); - - /* find a device that is not in use. */ - tty_lock(); - index = devpts_new_index(inode); - tty_unlock(); - if (index < 0) - return index; - - mutex_lock(&tty_mutex); - tty_lock(); - tty = tty_init_dev(ptm_driver, index, 1); - mutex_unlock(&tty_mutex); - - if (IS_ERR(tty)) { - retval = PTR_ERR(tty); - goto out; - } - - set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ - - retval = tty_add_file(tty, filp); - if (retval) - goto out; - - retval = devpts_pty_new(inode, tty->link); - if (retval) - goto out1; - - retval = ptm_driver->ops->open(tty, filp); - if (retval) - goto out2; -out1: - tty_unlock(); - return retval; -out2: - tty_unlock(); - tty_release(inode, filp); - return retval; -out: - devpts_kill_index(inode, index); - tty_unlock(); - return retval; -} - -static struct file_operations ptmx_fops; - -static void __init unix98_pty_init(void) -{ - ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX); - if (!ptm_driver) - panic("Couldn't allocate Unix98 ptm driver"); - pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX); - if (!pts_driver) - panic("Couldn't allocate Unix98 pts driver"); - - ptm_driver->owner = THIS_MODULE; - ptm_driver->driver_name = "pty_master"; - ptm_driver->name = "ptm"; - ptm_driver->major = UNIX98_PTY_MASTER_MAJOR; - ptm_driver->minor_start = 0; - ptm_driver->type = TTY_DRIVER_TYPE_PTY; - ptm_driver->subtype = PTY_TYPE_MASTER; - ptm_driver->init_termios = tty_std_termios; - ptm_driver->init_termios.c_iflag = 0; - ptm_driver->init_termios.c_oflag = 0; - ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; - ptm_driver->init_termios.c_lflag = 0; - ptm_driver->init_termios.c_ispeed = 38400; - ptm_driver->init_termios.c_ospeed = 38400; - ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW | - TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM; - ptm_driver->other = pts_driver; - tty_set_operations(ptm_driver, &ptm_unix98_ops); - - pts_driver->owner = THIS_MODULE; - pts_driver->driver_name = "pty_slave"; - pts_driver->name = "pts"; - pts_driver->major = UNIX98_PTY_SLAVE_MAJOR; - pts_driver->minor_start = 0; - pts_driver->type = TTY_DRIVER_TYPE_PTY; - pts_driver->subtype = PTY_TYPE_SLAVE; - pts_driver->init_termios = tty_std_termios; - pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; - pts_driver->init_termios.c_ispeed = 38400; - pts_driver->init_termios.c_ospeed = 38400; - pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW | - TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM; - pts_driver->other = ptm_driver; - tty_set_operations(pts_driver, &pty_unix98_ops); - - if (tty_register_driver(ptm_driver)) - panic("Couldn't register Unix98 ptm driver"); - if (tty_register_driver(pts_driver)) - panic("Couldn't register Unix98 pts driver"); - - register_sysctl_table(pty_root_table); - - /* Now create the /dev/ptmx special device */ - tty_default_fops(&ptmx_fops); - ptmx_fops.open = ptmx_open; - - cdev_init(&ptmx_cdev, &ptmx_fops); - if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) || - register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0) - panic("Couldn't register /dev/ptmx driver\n"); - device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); -} - -#else -static inline void unix98_pty_init(void) { } -#endif - -static int __init pty_init(void) -{ - legacy_pty_init(); - unix98_pty_init(); - return 0; -} -module_init(pty_init); diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c deleted file mode 100644 index eaa5d3e..0000000 --- a/drivers/char/sysrq.c +++ /dev/null @@ -1,811 +0,0 @@ -/* - * Linux Magic System Request Key Hacks - * - * (c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz> - * based on ideas by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz> - * - * (c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com> - * overhauled to use key registration - * based upon discusions in irc://irc.openprojects.net/#kernelnewbies - * - * Copyright (c) 2010 Dmitry Torokhov - * Input handler conversion - */ - -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - -#include <linux/sched.h> -#include <linux/interrupt.h> -#include <linux/mm.h> -#include <linux/fs.h> -#include <linux/mount.h> -#include <linux/kdev_t.h> -#include <linux/major.h> -#include <linux/reboot.h> -#include <linux/sysrq.h> -#include <linux/kbd_kern.h> -#include <linux/proc_fs.h> -#include <linux/nmi.h> -#include <linux/quotaops.h> -#include <linux/perf_event.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/suspend.h> -#include <linux/writeback.h> -#include <linux/buffer_head.h> /* for fsync_bdev() */ -#include <linux/swap.h> -#include <linux/spinlock.h> -#include <linux/vt_kern.h> -#include <linux/workqueue.h> -#include <linux/hrtimer.h> -#include <linux/oom.h> -#include <linux/slab.h> -#include <linux/input.h> - -#include <asm/ptrace.h> -#include <asm/irq_regs.h> - -/* Whether we react on sysrq keys or just ignore them */ -static int __read_mostly sysrq_enabled = 1; -static bool __read_mostly sysrq_always_enabled; - -static bool sysrq_on(void) -{ - return sysrq_enabled || sysrq_always_enabled; -} - -/* - * A value of 1 means 'all', other nonzero values are an op mask: - */ -static bool sysrq_on_mask(int mask) -{ - return sysrq_always_enabled || - sysrq_enabled == 1 || - (sysrq_enabled & mask); -} - -static int __init sysrq_always_enabled_setup(char *str) -{ - sysrq_always_enabled = true; - pr_info("sysrq always enabled.\n"); - - return 1; -} - -__setup("sysrq_always_enabled", sysrq_always_enabled_setup); - - -static void sysrq_handle_loglevel(int key) -{ - int i; - - i = key - '0'; - console_loglevel = 7; - printk("Loglevel set to %d\n", i); - console_loglevel = i; -} -static struct sysrq_key_op sysrq_loglevel_op = { - .handler = sysrq_handle_loglevel, - .help_msg = "loglevel(0-9)", - .action_msg = "Changing Loglevel", - .enable_mask = SYSRQ_ENABLE_LOG, -}; - -#ifdef CONFIG_VT -static void sysrq_handle_SAK(int key) -{ - struct work_struct *SAK_work = &vc_cons[fg_console].SAK_work; - schedule_work(SAK_work); -} -static struct sysrq_key_op sysrq_SAK_op = { - .handler = sysrq_handle_SAK, - .help_msg = "saK", - .action_msg = "SAK", - .enable_mask = SYSRQ_ENABLE_KEYBOARD, -}; -#else -#define sysrq_SAK_op (*(struct sysrq_key_op *)NULL) -#endif - -#ifdef CONFIG_VT -static void sysrq_handle_unraw(int key) -{ - struct kbd_struct *kbd = &kbd_table[fg_console]; - - if (kbd) - kbd->kbdmode = default_utf8 ? VC_UNICODE : VC_XLATE; -} -static struct sysrq_key_op sysrq_unraw_op = { - .handler = sysrq_handle_unraw, - .help_msg = "unRaw", - .action_msg = "Keyboard mode set to system default", - .enable_mask = SYSRQ_ENABLE_KEYBOARD, -}; -#else -#define sysrq_unraw_op (*(struct sysrq_key_op *)NULL) -#endif /* CONFIG_VT */ - -static void sysrq_handle_crash(int key) -{ - char *killer = NULL; - - panic_on_oops = 1; /* force panic */ - wmb(); - *killer = 1; -} -static struct sysrq_key_op sysrq_crash_op = { - .handler = sysrq_handle_crash, - .help_msg = "Crash", - .action_msg = "Trigger a crash", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; - -static void sysrq_handle_reboot(int key) -{ - lockdep_off(); - local_irq_enable(); - emergency_restart(); -} -static struct sysrq_key_op sysrq_reboot_op = { - .handler = sysrq_handle_reboot, - .help_msg = "reBoot", - .action_msg = "Resetting", - .enable_mask = SYSRQ_ENABLE_BOOT, -}; - -static void sysrq_handle_sync(int key) -{ - emergency_sync(); -} -static struct sysrq_key_op sysrq_sync_op = { - .handler = sysrq_handle_sync, - .help_msg = "Sync", - .action_msg = "Emergency Sync", - .enable_mask = SYSRQ_ENABLE_SYNC, -}; - -static void sysrq_handle_show_timers(int key) -{ - sysrq_timer_list_show(); -} - -static struct sysrq_key_op sysrq_show_timers_op = { - .handler = sysrq_handle_show_timers, - .help_msg = "show-all-timers(Q)", - .action_msg = "Show clockevent devices & pending hrtimers (no others)", -}; - -static void sysrq_handle_mountro(int key) -{ - emergency_remount(); -} -static struct sysrq_key_op sysrq_mountro_op = { - .handler = sysrq_handle_mountro, - .help_msg = "Unmount", - .action_msg = "Emergency Remount R/O", - .enable_mask = SYSRQ_ENABLE_REMOUNT, -}; - -#ifdef CONFIG_LOCKDEP -static void sysrq_handle_showlocks(int key) -{ - debug_show_all_locks(); -} - -static struct sysrq_key_op sysrq_showlocks_op = { - .handler = sysrq_handle_showlocks, - .help_msg = "show-all-locks(D)", - .action_msg = "Show Locks Held", -}; -#else -#define sysrq_showlocks_op (*(struct sysrq_key_op *)NULL) -#endif - -#ifdef CONFIG_SMP -static DEFINE_SPINLOCK(show_lock); - -static void showacpu(void *dummy) -{ - unsigned long flags; - - /* Idle CPUs have no interesting backtrace. */ - if (idle_cpu(smp_processor_id())) - return; - - spin_lock_irqsave(&show_lock, flags); - printk(KERN_INFO "CPU%d:\n", smp_processor_id()); - show_stack(NULL, NULL); - spin_unlock_irqrestore(&show_lock, flags); -} - -static void sysrq_showregs_othercpus(struct work_struct *dummy) -{ - smp_call_function(showacpu, NULL, 0); -} - -static DECLARE_WORK(sysrq_showallcpus, sysrq_showregs_othercpus); - -static void sysrq_handle_showallcpus(int key) -{ - /* - * Fall back to the workqueue based printing if the - * backtrace printing did not succeed or the - * architecture has no support for it: - */ - if (!trigger_all_cpu_backtrace()) { - struct pt_regs *regs = get_irq_regs(); - - if (regs) { - printk(KERN_INFO "CPU%d:\n", smp_processor_id()); - show_regs(regs); - } - schedule_work(&sysrq_showallcpus); - } -} - -static struct sysrq_key_op sysrq_showallcpus_op = { - .handler = sysrq_handle_showallcpus, - .help_msg = "show-backtrace-all-active-cpus(L)", - .action_msg = "Show backtrace of all active CPUs", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; -#endif - -static void sysrq_handle_showregs(int key) -{ - struct pt_regs *regs = get_irq_regs(); - if (regs) - show_regs(regs); - perf_event_print_debug(); -} -static struct sysrq_key_op sysrq_showregs_op = { - .handler = sysrq_handle_showregs, - .help_msg = "show-registers(P)", - .action_msg = "Show Regs", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; - -static void sysrq_handle_showstate(int key) -{ - show_state(); -} -static struct sysrq_key_op sysrq_showstate_op = { - .handler = sysrq_handle_showstate, - .help_msg = "show-task-states(T)", - .action_msg = "Show State", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; - -static void sysrq_handle_showstate_blocked(int key) -{ - show_state_filter(TASK_UNINTERRUPTIBLE); -} -static struct sysrq_key_op sysrq_showstate_blocked_op = { - .handler = sysrq_handle_showstate_blocked, - .help_msg = "show-blocked-tasks(W)", - .action_msg = "Show Blocked State", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; - -#ifdef CONFIG_TRACING -#include <linux/ftrace.h> - -static void sysrq_ftrace_dump(int key) -{ - ftrace_dump(DUMP_ALL); -} -static struct sysrq_key_op sysrq_ftrace_dump_op = { - .handler = sysrq_ftrace_dump, - .help_msg = "dump-ftrace-buffer(Z)", - .action_msg = "Dump ftrace buffer", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; -#else -#define sysrq_ftrace_dump_op (*(struct sysrq_key_op *)NULL) -#endif - -static void sysrq_handle_showmem(int key) -{ - show_mem(); -} -static struct sysrq_key_op sysrq_showmem_op = { - .handler = sysrq_handle_showmem, - .help_msg = "show-memory-usage(M)", - .action_msg = "Show Memory", - .enable_mask = SYSRQ_ENABLE_DUMP, -}; - -/* - * Signal sysrq helper function. Sends a signal to all user processes. - */ -static void send_sig_all(int sig) -{ - struct task_struct *p; - - for_each_process(p) { - if (p->mm && !is_global_init(p)) - /* Not swapper, init nor kernel thread */ - force_sig(sig, p); - } -} - -static void sysrq_handle_term(int key) -{ - send_sig_all(SIGTERM); - console_loglevel = 8; -} -static struct sysrq_key_op sysrq_term_op = { - .handler = sysrq_handle_term, - .help_msg = "terminate-all-tasks(E)", - .action_msg = "Terminate All Tasks", - .enable_mask = SYSRQ_ENABLE_SIGNAL, -}; - -static void moom_callback(struct work_struct *ignored) -{ - out_of_memory(node_zonelist(0, GFP_KERNEL), GFP_KERNEL, 0, NULL); -} - -static DECLARE_WORK(moom_work, moom_callback); - -static void sysrq_handle_moom(int key) -{ - schedule_work(&moom_work); -} -static struct sysrq_key_op sysrq_moom_op = { - .handler = sysrq_handle_moom, - .help_msg = "memory-full-oom-kill(F)", - .action_msg = "Manual OOM execution", - .enable_mask = SYSRQ_ENABLE_SIGNAL, -}; - -#ifdef CONFIG_BLOCK -static void sysrq_handle_thaw(int key) -{ - emergency_thaw_all(); -} -static struct sysrq_key_op sysrq_thaw_op = { - .handler = sysrq_handle_thaw, - .help_msg = "thaw-filesystems(J)", - .action_msg = "Emergency Thaw of all frozen filesystems", - .enable_mask = SYSRQ_ENABLE_SIGNAL, -}; -#endif - -static void sysrq_handle_kill(int key) -{ - send_sig_all(SIGKILL); - console_loglevel = 8; -} -static struct sysrq_key_op sysrq_kill_op = { - .handler = sysrq_handle_kill, - .help_msg = "kill-all-tasks(I)", - .action_msg = "Kill All Tasks", - .enable_mask = SYSRQ_ENABLE_SIGNAL, -}; - -static void sysrq_handle_unrt(int key) -{ - normalize_rt_tasks(); -} -static struct sysrq_key_op sysrq_unrt_op = { - .handler = sysrq_handle_unrt, - .help_msg = "nice-all-RT-tasks(N)", - .action_msg = "Nice All RT Tasks", - .enable_mask = SYSRQ_ENABLE_RTNICE, -}; - -/* Key Operations table and lock */ -static DEFINE_SPINLOCK(sysrq_key_table_lock); - -static struct sysrq_key_op *sysrq_key_table[36] = { - &sysrq_loglevel_op, /* 0 */ - &sysrq_loglevel_op, /* 1 */ - &sysrq_loglevel_op, /* 2 */ - &sysrq_loglevel_op, /* 3 */ - &sysrq_loglevel_op, /* 4 */ - &sysrq_loglevel_op, /* 5 */ - &sysrq_loglevel_op, /* 6 */ - &sysrq_loglevel_op, /* 7 */ - &sysrq_loglevel_op, /* 8 */ - &sysrq_loglevel_op, /* 9 */ - - /* - * a: Don't use for system provided sysrqs, it is handled specially on - * sparc and will never arrive. - */ - NULL, /* a */ - &sysrq_reboot_op, /* b */ - &sysrq_crash_op, /* c & ibm_emac driver debug */ - &sysrq_showlocks_op, /* d */ - &sysrq_term_op, /* e */ - &sysrq_moom_op, /* f */ - /* g: May be registered for the kernel debugger */ - NULL, /* g */ - NULL, /* h - reserved for help */ - &sysrq_kill_op, /* i */ -#ifdef CONFIG_BLOCK - &sysrq_thaw_op, /* j */ -#else - NULL, /* j */ -#endif - &sysrq_SAK_op, /* k */ -#ifdef CONFIG_SMP - &sysrq_showallcpus_op, /* l */ -#else - NULL, /* l */ -#endif - &sysrq_showmem_op, /* m */ - &sysrq_unrt_op, /* n */ - /* o: This will often be registered as 'Off' at init time */ - NULL, /* o */ - &sysrq_showregs_op, /* p */ - &sysrq_show_timers_op, /* q */ - &sysrq_unraw_op, /* r */ - &sysrq_sync_op, /* s */ - &sysrq_showstate_op, /* t */ - &sysrq_mountro_op, /* u */ - /* v: May be registered for frame buffer console restore */ - NULL, /* v */ - &sysrq_showstate_blocked_op, /* w */ - /* x: May be registered on ppc/powerpc for xmon */ - NULL, /* x */ - /* y: May be registered on sparc64 for global register dump */ - NULL, /* y */ - &sysrq_ftrace_dump_op, /* z */ -}; - -/* key2index calculation, -1 on invalid index */ -static int sysrq_key_table_key2index(int key) -{ - int retval; - - if ((key >= '0') && (key <= '9')) - retval = key - '0'; - else if ((key >= 'a') && (key <= 'z')) - retval = key + 10 - 'a'; - else - retval = -1; - return retval; -} - -/* - * get and put functions for the table, exposed to modules. - */ -struct sysrq_key_op *__sysrq_get_key_op(int key) -{ - struct sysrq_key_op *op_p = NULL; - int i; - - i = sysrq_key_table_key2index(key); - if (i != -1) - op_p = sysrq_key_table[i]; - - return op_p; -} - -static void __sysrq_put_key_op(int key, struct sysrq_key_op *op_p) -{ - int i = sysrq_key_table_key2index(key); - - if (i != -1) - sysrq_key_table[i] = op_p; -} - -void __handle_sysrq(int key, bool check_mask) -{ - struct sysrq_key_op *op_p; - int orig_log_level; - int i; - unsigned long flags; - - spin_lock_irqsave(&sysrq_key_table_lock, flags); - /* - * Raise the apparent loglevel to maximum so that the sysrq header - * is shown to provide the user with positive feedback. We do not - * simply emit this at KERN_EMERG as that would change message - * routing in the consumers of /proc/kmsg. - */ - orig_log_level = console_loglevel; - console_loglevel = 7; - printk(KERN_INFO "SysRq : "); - - op_p = __sysrq_get_key_op(key); - if (op_p) { - /* - * Should we check for enabled operations (/proc/sysrq-trigger - * should not) and is the invoked operation enabled? - */ - if (!check_mask || sysrq_on_mask(op_p->enable_mask)) { - printk("%s\n", op_p->action_msg); - console_loglevel = orig_log_level; - op_p->handler(key); - } else { - printk("This sysrq operation is disabled.\n"); - } - } else { - printk("HELP : "); - /* Only print the help msg once per handler */ - for (i = 0; i < ARRAY_SIZE(sysrq_key_table); i++) { - if (sysrq_key_table[i]) { - int j; - - for (j = 0; sysrq_key_table[i] != - sysrq_key_table[j]; j++) - ; - if (j != i) - continue; - printk("%s ", sysrq_key_table[i]->help_msg); - } - } - printk("\n"); - console_loglevel = orig_log_level; - } - spin_unlock_irqrestore(&sysrq_key_table_lock, flags); -} - -void handle_sysrq(int key) -{ - if (sysrq_on()) - __handle_sysrq(key, true); -} -EXPORT_SYMBOL(handle_sysrq); - -#ifdef CONFIG_INPUT - -/* Simple translation table for the SysRq keys */ -static const unsigned char sysrq_xlate[KEY_MAX + 1] = - "\000\0331234567890-=\177\t" /* 0x00 - 0x0f */ - "qwertyuiop[]\r\000as" /* 0x10 - 0x1f */ - "dfghjkl;'`\000\\zxcv" /* 0x20 - 0x2f */ - "bnm,./\000*\000 \000\201\202\203\204\205" /* 0x30 - 0x3f */ - "\206\207\210\211\212\000\000789-456+1" /* 0x40 - 0x4f */ - "230\177\000\000\213\214\000\000\000\000\000\000\000\000\000\000" /* 0x50 - 0x5f */ - "\r\000/"; /* 0x60 - 0x6f */ - -static bool sysrq_down; -static int sysrq_alt_use; -static int sysrq_alt; -static DEFINE_SPINLOCK(sysrq_event_lock); - -static bool sysrq_filter(struct input_handle *handle, unsigned int type, - unsigned int code, int value) -{ - bool suppress; - - /* We are called with interrupts disabled, just take the lock */ - spin_lock(&sysrq_event_lock); - - if (type != EV_KEY) - goto out; - - switch (code) { - - case KEY_LEFTALT: - case KEY_RIGHTALT: - if (value) - sysrq_alt = code; - else { - if (sysrq_down && code == sysrq_alt_use) - sysrq_down = false; - - sysrq_alt = 0; - } - break; - - case KEY_SYSRQ: - if (value == 1 && sysrq_alt) { - sysrq_down = true; - sysrq_alt_use = sysrq_alt; - } - break; - - default: - if (sysrq_down && value && value != 2) - __handle_sysrq(sysrq_xlate[code], true); - break; - } - -out: - suppress = sysrq_down; - spin_unlock(&sysrq_event_lock); - - return suppress; -} - -static int sysrq_connect(struct input_handler *handler, - struct input_dev *dev, - const struct input_device_id *id) -{ - struct input_handle *handle; - int error; - - sysrq_down = false; - sysrq_alt = 0; - - handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL); - if (!handle) - return -ENOMEM; - - handle->dev = dev; - handle->handler = handler; - handle->name = "sysrq"; - - error = input_register_handle(handle); - if (error) { - pr_err("Failed to register input sysrq handler, error %d\n", - error); - goto err_free; - } - - error = input_open_device(handle); - if (error) { - pr_err("Failed to open input device, error %d\n", error); - goto err_unregister; - } - - return 0; - - err_unregister: - input_unregister_handle(handle); - err_free: - kfree(handle); - return error; -} - -static void sysrq_disconnect(struct input_handle *handle) -{ - input_close_device(handle); - input_unregister_handle(handle); - kfree(handle); -} - -/* - * We are matching on KEY_LEFTALT instead of KEY_SYSRQ because not all - * keyboards have SysRq key predefined and so user may add it to keymap - * later, but we expect all such keyboards to have left alt. - */ -static const struct input_device_id sysrq_ids[] = { - { - .flags = INPUT_DEVICE_ID_MATCH_EVBIT | - INPUT_DEVICE_ID_MATCH_KEYBIT, - .evbit = { BIT_MASK(EV_KEY) }, - .keybit = { BIT_MASK(KEY_LEFTALT) }, - }, - { }, -}; - -static struct input_handler sysrq_handler = { - .filter = sysrq_filter, - .connect = sysrq_connect, - .disconnect = sysrq_disconnect, - .name = "sysrq", - .id_table = sysrq_ids, -}; - -static bool sysrq_handler_registered; - -static inline void sysrq_register_handler(void) -{ - int error; - - error = input_register_handler(&sysrq_handler); - if (error) - pr_err("Failed to register input handler, error %d", error); - else - sysrq_handler_registered = true; -} - -static inline void sysrq_unregister_handler(void) -{ - if (sysrq_handler_registered) { - input_unregister_handler(&sysrq_handler); - sysrq_handler_registered = false; - } -} - -#else - -static inline void sysrq_register_handler(void) -{ -} - -static inline void sysrq_unregister_handler(void) -{ -} - -#endif /* CONFIG_INPUT */ - -int sysrq_toggle_support(int enable_mask) -{ - bool was_enabled = sysrq_on(); - - sysrq_enabled = enable_mask; - - if (was_enabled != sysrq_on()) { - if (sysrq_on()) - sysrq_register_handler(); - else - sysrq_unregister_handler(); - } - - return 0; -} - -static int __sysrq_swap_key_ops(int key, struct sysrq_key_op *insert_op_p, - struct sysrq_key_op *remove_op_p) -{ - int retval; - unsigned long flags; - - spin_lock_irqsave(&sysrq_key_table_lock, flags); - if (__sysrq_get_key_op(key) == remove_op_p) { - __sysrq_put_key_op(key, insert_op_p); - retval = 0; - } else { - retval = -1; - } - spin_unlock_irqrestore(&sysrq_key_table_lock, flags); - return retval; -} - -int register_sysrq_key(int key, struct sysrq_key_op *op_p) -{ - return __sysrq_swap_key_ops(key, op_p, NULL); -} -EXPORT_SYMBOL(register_sysrq_key); - -int unregister_sysrq_key(int key, struct sysrq_key_op *op_p) -{ - return __sysrq_swap_key_ops(key, NULL, op_p); -} -EXPORT_SYMBOL(unregister_sysrq_key); - -#ifdef CONFIG_PROC_FS -/* - * writing 'C' to /proc/sysrq-trigger is like sysrq-C - */ -static ssize_t write_sysrq_trigger(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) -{ - if (count) { - char c; - - if (get_user(c, buf)) - return -EFAULT; - __handle_sysrq(c, false); - } - - return count; -} - -static const struct file_operations proc_sysrq_trigger_operations = { - .write = write_sysrq_trigger, - .llseek = noop_llseek, -}; - -static void sysrq_init_procfs(void) -{ - if (!proc_create("sysrq-trigger", S_IWUSR, NULL, - &proc_sysrq_trigger_operations)) - pr_err("Failed to register proc interface\n"); -} - -#else - -static inline void sysrq_init_procfs(void) -{ -} - -#endif /* CONFIG_PROC_FS */ - -static int __init sysrq_init(void) -{ - sysrq_init_procfs(); - - if (sysrq_on()) - sysrq_register_handler(); - - return 0; -} -module_init(sysrq_init); diff --git a/drivers/char/tty_audit.c b/drivers/char/tty_audit.c deleted file mode 100644 index f64582b..0000000 --- a/drivers/char/tty_audit.c +++ /dev/null @@ -1,358 +0,0 @@ -/* - * Creating audit events from TTY input. - * - * Copyright (C) 2007 Red Hat, Inc. All rights reserved. This copyrighted - * material is made available to anyone wishing to use, modify, copy, or - * redistribute it subject to the terms and conditions of the GNU General - * Public License v.2. - * - * Authors: Miloslav Trmac <mitr@redhat.com> - */ - -#include <linux/audit.h> -#include <linux/slab.h> -#include <linux/tty.h> - -struct tty_audit_buf { - atomic_t count; - struct mutex mutex; /* Protects all data below */ - int major, minor; /* The TTY which the data is from */ - unsigned icanon:1; - size_t valid; - unsigned char *data; /* Allocated size N_TTY_BUF_SIZE */ -}; - -static struct tty_audit_buf *tty_audit_buf_alloc(int major, int minor, - int icanon) -{ - struct tty_audit_buf *buf; - - buf = kmalloc(sizeof(*buf), GFP_KERNEL); - if (!buf) - goto err; - buf->data = kmalloc(N_TTY_BUF_SIZE, GFP_KERNEL); - if (!buf->data) - goto err_buf; - atomic_set(&buf->count, 1); - mutex_init(&buf->mutex); - buf->major = major; - buf->minor = minor; - buf->icanon = icanon; - buf->valid = 0; - return buf; - -err_buf: - kfree(buf); -err: - return NULL; -} - -static void tty_audit_buf_free(struct tty_audit_buf *buf) -{ - WARN_ON(buf->valid != 0); - kfree(buf->data); - kfree(buf); -} - -static void tty_audit_buf_put(struct tty_audit_buf *buf) -{ - if (atomic_dec_and_test(&buf->count)) - tty_audit_buf_free(buf); -} - -static void tty_audit_log(const char *description, struct task_struct *tsk, - uid_t loginuid, unsigned sessionid, int major, - int minor, unsigned char *data, size_t size) -{ - struct audit_buffer *ab; - - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_TTY); - if (ab) { - char name[sizeof(tsk->comm)]; - uid_t uid = task_uid(tsk); - - audit_log_format(ab, "%s pid=%u uid=%u auid=%u ses=%u " - "major=%d minor=%d comm=", description, - tsk->pid, uid, loginuid, sessionid, - major, minor); - get_task_comm(name, tsk); - audit_log_untrustedstring(ab, name); - audit_log_format(ab, " data="); - audit_log_n_hex(ab, data, size); - audit_log_end(ab); - } -} - -/** - * tty_audit_buf_push - Push buffered data out - * - * Generate an audit message from the contents of @buf, which is owned by - * @tsk with @loginuid. @buf->mutex must be locked. - */ -static void tty_audit_buf_push(struct task_struct *tsk, uid_t loginuid, - unsigned int sessionid, - struct tty_audit_buf *buf) -{ - if (buf->valid == 0) - return; - if (audit_enabled == 0) - return; - tty_audit_log("tty", tsk, loginuid, sessionid, buf->major, buf->minor, - buf->data, buf->valid); - buf->valid = 0; -} - -/** - * tty_audit_buf_push_current - Push buffered data out - * - * Generate an audit message from the contents of @buf, which is owned by - * the current task. @buf->mutex must be locked. - */ -static void tty_audit_buf_push_current(struct tty_audit_buf *buf) -{ - uid_t auid = audit_get_loginuid(current); - unsigned int sessionid = audit_get_sessionid(current); - tty_audit_buf_push(current, auid, sessionid, buf); -} - -/** - * tty_audit_exit - Handle a task exit - * - * Make sure all buffered data is written out and deallocate the buffer. - * Only needs to be called if current->signal->tty_audit_buf != %NULL. - */ -void tty_audit_exit(void) -{ - struct tty_audit_buf *buf; - - spin_lock_irq(¤t->sighand->siglock); - buf = current->signal->tty_audit_buf; - current->signal->tty_audit_buf = NULL; - spin_unlock_irq(¤t->sighand->siglock); - if (!buf) - return; - - mutex_lock(&buf->mutex); - tty_audit_buf_push_current(buf); - mutex_unlock(&buf->mutex); - - tty_audit_buf_put(buf); -} - -/** - * tty_audit_fork - Copy TTY audit state for a new task - * - * Set up TTY audit state in @sig from current. @sig needs no locking. - */ -void tty_audit_fork(struct signal_struct *sig) -{ - spin_lock_irq(¤t->sighand->siglock); - sig->audit_tty = current->signal->audit_tty; - spin_unlock_irq(¤t->sighand->siglock); -} - -/** - * tty_audit_tiocsti - Log TIOCSTI - */ -void tty_audit_tiocsti(struct tty_struct *tty, char ch) -{ - struct tty_audit_buf *buf; - int major, minor, should_audit; - - spin_lock_irq(¤t->sighand->siglock); - should_audit = current->signal->audit_tty; - buf = current->signal->tty_audit_buf; - if (buf) - atomic_inc(&buf->count); - spin_unlock_irq(¤t->sighand->siglock); - - major = tty->driver->major; - minor = tty->driver->minor_start + tty->index; - if (buf) { - mutex_lock(&buf->mutex); - if (buf->major == major && buf->minor == minor) - tty_audit_buf_push_current(buf); - mutex_unlock(&buf->mutex); - tty_audit_buf_put(buf); - } - - if (should_audit && audit_enabled) { - uid_t auid; - unsigned int sessionid; - - auid = audit_get_loginuid(current); - sessionid = audit_get_sessionid(current); - tty_audit_log("ioctl=TIOCSTI", current, auid, sessionid, major, - minor, &ch, 1); - } -} - -/** - * tty_audit_push_task - Flush task's pending audit data - * @tsk: task pointer - * @loginuid: sender login uid - * @sessionid: sender session id - * - * Called with a ref on @tsk held. Try to lock sighand and get a - * reference to the tty audit buffer if available. - * Flush the buffer or return an appropriate error code. - */ -int tty_audit_push_task(struct task_struct *tsk, uid_t loginuid, u32 sessionid) -{ - struct tty_audit_buf *buf = ERR_PTR(-EPERM); - unsigned long flags; - - if (!lock_task_sighand(tsk, &flags)) - return -ESRCH; - - if (tsk->signal->audit_tty) { - buf = tsk->signal->tty_audit_buf; - if (buf) - atomic_inc(&buf->count); - } - unlock_task_sighand(tsk, &flags); - - /* - * Return 0 when signal->audit_tty set - * but tsk->signal->tty_audit_buf == NULL. - */ - if (!buf || IS_ERR(buf)) - return PTR_ERR(buf); - - mutex_lock(&buf->mutex); - tty_audit_buf_push(tsk, loginuid, sessionid, buf); - mutex_unlock(&buf->mutex); - - tty_audit_buf_put(buf); - return 0; -} - -/** - * tty_audit_buf_get - Get an audit buffer. - * - * Get an audit buffer for @tty, allocate it if necessary. Return %NULL - * if TTY auditing is disabled or out of memory. Otherwise, return a new - * reference to the buffer. - */ -static struct tty_audit_buf *tty_audit_buf_get(struct tty_struct *tty) -{ - struct tty_audit_buf *buf, *buf2; - - buf = NULL; - buf2 = NULL; - spin_lock_irq(¤t->sighand->siglock); - if (likely(!current->signal->audit_tty)) - goto out; - buf = current->signal->tty_audit_buf; - if (buf) { - atomic_inc(&buf->count); - goto out; - } - spin_unlock_irq(¤t->sighand->siglock); - - buf2 = tty_audit_buf_alloc(tty->driver->major, - tty->driver->minor_start + tty->index, - tty->icanon); - if (buf2 == NULL) { - audit_log_lost("out of memory in TTY auditing"); - return NULL; - } - - spin_lock_irq(¤t->sighand->siglock); - if (!current->signal->audit_tty) - goto out; - buf = current->signal->tty_audit_buf; - if (!buf) { - current->signal->tty_audit_buf = buf2; - buf = buf2; - buf2 = NULL; - } - atomic_inc(&buf->count); - /* Fall through */ - out: - spin_unlock_irq(¤t->sighand->siglock); - if (buf2) - tty_audit_buf_free(buf2); - return buf; -} - -/** - * tty_audit_add_data - Add data for TTY auditing. - * - * Audit @data of @size from @tty, if necessary. - */ -void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, - size_t size) -{ - struct tty_audit_buf *buf; - int major, minor; - - if (unlikely(size == 0)) - return; - - if (tty->driver->type == TTY_DRIVER_TYPE_PTY - && tty->driver->subtype == PTY_TYPE_MASTER) - return; - - buf = tty_audit_buf_get(tty); - if (!buf) - return; - - mutex_lock(&buf->mutex); - major = tty->driver->major; - minor = tty->driver->minor_start + tty->index; - if (buf->major != major || buf->minor != minor - || buf->icanon != tty->icanon) { - tty_audit_buf_push_current(buf); - buf->major = major; - buf->minor = minor; - buf->icanon = tty->icanon; - } - do { - size_t run; - - run = N_TTY_BUF_SIZE - buf->valid; - if (run > size) - run = size; - memcpy(buf->data + buf->valid, data, run); - buf->valid += run; - data += run; - size -= run; - if (buf->valid == N_TTY_BUF_SIZE) - tty_audit_buf_push_current(buf); - } while (size != 0); - mutex_unlock(&buf->mutex); - tty_audit_buf_put(buf); -} - -/** - * tty_audit_push - Push buffered data out - * - * Make sure no audit data is pending for @tty on the current process. - */ -void tty_audit_push(struct tty_struct *tty) -{ - struct tty_audit_buf *buf; - - spin_lock_irq(¤t->sighand->siglock); - if (likely(!current->signal->audit_tty)) { - spin_unlock_irq(¤t->sighand->siglock); - return; - } - buf = current->signal->tty_audit_buf; - if (buf) - atomic_inc(&buf->count); - spin_unlock_irq(¤t->sighand->siglock); - - if (buf) { - int major, minor; - - major = tty->driver->major; - minor = tty->driver->minor_start + tty->index; - mutex_lock(&buf->mutex); - if (buf->major == major && buf->minor == minor) - tty_audit_buf_push_current(buf); - mutex_unlock(&buf->mutex); - tty_audit_buf_put(buf); - } -} diff --git a/drivers/char/tty_buffer.c b/drivers/char/tty_buffer.c deleted file mode 100644 index cc1e985..0000000 --- a/drivers/char/tty_buffer.c +++ /dev/null @@ -1,524 +0,0 @@ -/* - * Tty buffer allocation management - */ - -#include <linux/types.h> -#include <linux/errno.h> -#include <linux/tty.h> -#include <linux/tty_driver.h> -#include <linux/tty_flip.h> -#include <linux/timer.h> -#include <linux/string.h> -#include <linux/slab.h> -#include <linux/sched.h> -#include <linux/init.h> -#include <linux/wait.h> -#include <linux/bitops.h> -#include <linux/delay.h> -#include <linux/module.h> - -/** - * tty_buffer_free_all - free buffers used by a tty - * @tty: tty to free from - * - * Remove all the buffers pending on a tty whether queued with data - * or in the free ring. Must be called when the tty is no longer in use - * - * Locking: none - */ - -void tty_buffer_free_all(struct tty_struct *tty) -{ - struct tty_buffer *thead; - while ((thead = tty->buf.head) != NULL) { - tty->buf.head = thead->next; - kfree(thead); - } - while ((thead = tty->buf.free) != NULL) { - tty->buf.free = thead->next; - kfree(thead); - } - tty->buf.tail = NULL; - tty->buf.memory_used = 0; -} - -/** - * tty_buffer_alloc - allocate a tty buffer - * @tty: tty device - * @size: desired size (characters) - * - * Allocate a new tty buffer to hold the desired number of characters. - * Return NULL if out of memory or the allocation would exceed the - * per device queue - * - * Locking: Caller must hold tty->buf.lock - */ - -static struct tty_buffer *tty_buffer_alloc(struct tty_struct *tty, size_t size) -{ - struct tty_buffer *p; - - if (tty->buf.memory_used + size > 65536) - return NULL; - p = kmalloc(sizeof(struct tty_buffer) + 2 * size, GFP_ATOMIC); - if (p == NULL) - return NULL; - p->used = 0; - p->size = size; - p->next = NULL; - p->commit = 0; - p->read = 0; - p->char_buf_ptr = (char *)(p->data); - p->flag_buf_ptr = (unsigned char *)p->char_buf_ptr + size; - tty->buf.memory_used += size; - return p; -} - -/** - * tty_buffer_free - free a tty buffer - * @tty: tty owning the buffer - * @b: the buffer to free - * - * Free a tty buffer, or add it to the free list according to our - * internal strategy - * - * Locking: Caller must hold tty->buf.lock - */ - -static void tty_buffer_free(struct tty_struct *tty, struct tty_buffer *b) -{ - /* Dumb strategy for now - should keep some stats */ - tty->buf.memory_used -= b->size; - WARN_ON(tty->buf.memory_used < 0); - - if (b->size >= 512) - kfree(b); - else { - b->next = tty->buf.free; - tty->buf.free = b; - } -} - -/** - * __tty_buffer_flush - flush full tty buffers - * @tty: tty to flush - * - * flush all the buffers containing receive data. Caller must - * hold the buffer lock and must have ensured no parallel flush to - * ldisc is running. - * - * Locking: Caller must hold tty->buf.lock - */ - -static void __tty_buffer_flush(struct tty_struct *tty) -{ - struct tty_buffer *thead; - - while ((thead = tty->buf.head) != NULL) { - tty->buf.head = thead->next; - tty_buffer_free(tty, thead); - } - tty->buf.tail = NULL; -} - -/** - * tty_buffer_flush - flush full tty buffers - * @tty: tty to flush - * - * flush all the buffers containing receive data. If the buffer is - * being processed by flush_to_ldisc then we defer the processing - * to that function - * - * Locking: none - */ - -void tty_buffer_flush(struct tty_struct *tty) -{ - unsigned long flags; - spin_lock_irqsave(&tty->buf.lock, flags); - - /* If the data is being pushed to the tty layer then we can't - process it here. Instead set a flag and the flush_to_ldisc - path will process the flush request before it exits */ - if (test_bit(TTY_FLUSHING, &tty->flags)) { - set_bit(TTY_FLUSHPENDING, &tty->flags); - spin_unlock_irqrestore(&tty->buf.lock, flags); - wait_event(tty->read_wait, - test_bit(TTY_FLUSHPENDING, &tty->flags) == 0); - return; - } else - __tty_buffer_flush(tty); - spin_unlock_irqrestore(&tty->buf.lock, flags); -} - -/** - * tty_buffer_find - find a free tty buffer - * @tty: tty owning the buffer - * @size: characters wanted - * - * Locate an existing suitable tty buffer or if we are lacking one then - * allocate a new one. We round our buffers off in 256 character chunks - * to get better allocation behaviour. - * - * Locking: Caller must hold tty->buf.lock - */ - -static struct tty_buffer *tty_buffer_find(struct tty_struct *tty, size_t size) -{ - struct tty_buffer **tbh = &tty->buf.free; - while ((*tbh) != NULL) { - struct tty_buffer *t = *tbh; - if (t->size >= size) { - *tbh = t->next; - t->next = NULL; - t->used = 0; - t->commit = 0; - t->read = 0; - tty->buf.memory_used += t->size; - return t; - } - tbh = &((*tbh)->next); - } - /* Round the buffer size out */ - size = (size + 0xFF) & ~0xFF; - return tty_buffer_alloc(tty, size); - /* Should possibly check if this fails for the largest buffer we - have queued and recycle that ? */ -} - -/** - * tty_buffer_request_room - grow tty buffer if needed - * @tty: tty structure - * @size: size desired - * - * Make at least size bytes of linear space available for the tty - * buffer. If we fail return the size we managed to find. - * - * Locking: Takes tty->buf.lock - */ -int tty_buffer_request_room(struct tty_struct *tty, size_t size) -{ - struct tty_buffer *b, *n; - int left; - unsigned long flags; - - spin_lock_irqsave(&tty->buf.lock, flags); - - /* OPTIMISATION: We could keep a per tty "zero" sized buffer to - remove this conditional if its worth it. This would be invisible - to the callers */ - if ((b = tty->buf.tail) != NULL) - left = b->size - b->used; - else - left = 0; - - if (left < size) { - /* This is the slow path - looking for new buffers to use */ - if ((n = tty_buffer_find(tty, size)) != NULL) { - if (b != NULL) { - b->next = n; - b->commit = b->used; - } else - tty->buf.head = n; - tty->buf.tail = n; - } else - size = left; - } - - spin_unlock_irqrestore(&tty->buf.lock, flags); - return size; -} -EXPORT_SYMBOL_GPL(tty_buffer_request_room); - -/** - * tty_insert_flip_string_fixed_flag - Add characters to the tty buffer - * @tty: tty structure - * @chars: characters - * @flag: flag value for each character - * @size: size - * - * Queue a series of bytes to the tty buffering. All the characters - * passed are marked with the supplied flag. Returns the number added. - * - * Locking: Called functions may take tty->buf.lock - */ - -int tty_insert_flip_string_fixed_flag(struct tty_struct *tty, - const unsigned char *chars, char flag, size_t size) -{ - int copied = 0; - do { - int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE); - int space = tty_buffer_request_room(tty, goal); - struct tty_buffer *tb = tty->buf.tail; - /* If there is no space then tb may be NULL */ - if (unlikely(space == 0)) - break; - memcpy(tb->char_buf_ptr + tb->used, chars, space); - memset(tb->flag_buf_ptr + tb->used, flag, space); - tb->used += space; - copied += space; - chars += space; - /* There is a small chance that we need to split the data over - several buffers. If this is the case we must loop */ - } while (unlikely(size > copied)); - return copied; -} -EXPORT_SYMBOL(tty_insert_flip_string_fixed_flag); - -/** - * tty_insert_flip_string_flags - Add characters to the tty buffer - * @tty: tty structure - * @chars: characters - * @flags: flag bytes - * @size: size - * - * Queue a series of bytes to the tty buffering. For each character - * the flags array indicates the status of the character. Returns the - * number added. - * - * Locking: Called functions may take tty->buf.lock - */ - -int tty_insert_flip_string_flags(struct tty_struct *tty, - const unsigned char *chars, const char *flags, size_t size) -{ - int copied = 0; - do { - int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE); - int space = tty_buffer_request_room(tty, goal); - struct tty_buffer *tb = tty->buf.tail; - /* If there is no space then tb may be NULL */ - if (unlikely(space == 0)) - break; - memcpy(tb->char_buf_ptr + tb->used, chars, space); - memcpy(tb->flag_buf_ptr + tb->used, flags, space); - tb->used += space; - copied += space; - chars += space; - flags += space; - /* There is a small chance that we need to split the data over - several buffers. If this is the case we must loop */ - } while (unlikely(size > copied)); - return copied; -} -EXPORT_SYMBOL(tty_insert_flip_string_flags); - -/** - * tty_schedule_flip - push characters to ldisc - * @tty: tty to push from - * - * Takes any pending buffers and transfers their ownership to the - * ldisc side of the queue. It then schedules those characters for - * processing by the line discipline. - * - * Locking: Takes tty->buf.lock - */ - -void tty_schedule_flip(struct tty_struct *tty) -{ - unsigned long flags; - spin_lock_irqsave(&tty->buf.lock, flags); - if (tty->buf.tail != NULL) - tty->buf.tail->commit = tty->buf.tail->used; - spin_unlock_irqrestore(&tty->buf.lock, flags); - schedule_delayed_work(&tty->buf.work, 1); -} -EXPORT_SYMBOL(tty_schedule_flip); - -/** - * tty_prepare_flip_string - make room for characters - * @tty: tty - * @chars: return pointer for character write area - * @size: desired size - * - * Prepare a block of space in the buffer for data. Returns the length - * available and buffer pointer to the space which is now allocated and - * accounted for as ready for normal characters. This is used for drivers - * that need their own block copy routines into the buffer. There is no - * guarantee the buffer is a DMA target! - * - * Locking: May call functions taking tty->buf.lock - */ - -int tty_prepare_flip_string(struct tty_struct *tty, unsigned char **chars, - size_t size) -{ - int space = tty_buffer_request_room(tty, size); - if (likely(space)) { - struct tty_buffer *tb = tty->buf.tail; - *chars = tb->char_buf_ptr + tb->used; - memset(tb->flag_buf_ptr + tb->used, TTY_NORMAL, space); - tb->used += space; - } - return space; -} -EXPORT_SYMBOL_GPL(tty_prepare_flip_string); - -/** - * tty_prepare_flip_string_flags - make room for characters - * @tty: tty - * @chars: return pointer for character write area - * @flags: return pointer for status flag write area - * @size: desired size - * - * Prepare a block of space in the buffer for data. Returns the length - * available and buffer pointer to the space which is now allocated and - * accounted for as ready for characters. This is used for drivers - * that need their own block copy routines into the buffer. There is no - * guarantee the buffer is a DMA target! - * - * Locking: May call functions taking tty->buf.lock - */ - -int tty_prepare_flip_string_flags(struct tty_struct *tty, - unsigned char **chars, char **flags, size_t size) -{ - int space = tty_buffer_request_room(tty, size); - if (likely(space)) { - struct tty_buffer *tb = tty->buf.tail; - *chars = tb->char_buf_ptr + tb->used; - *flags = tb->flag_buf_ptr + tb->used; - tb->used += space; - } - return space; -} -EXPORT_SYMBOL_GPL(tty_prepare_flip_string_flags); - - - -/** - * flush_to_ldisc - * @work: tty structure passed from work queue. - * - * This routine is called out of the software interrupt to flush data - * from the buffer chain to the line discipline. - * - * Locking: holds tty->buf.lock to guard buffer list. Drops the lock - * while invoking the line discipline receive_buf method. The - * receive_buf method is single threaded for each tty instance. - */ - -static void flush_to_ldisc(struct work_struct *work) -{ - struct tty_struct *tty = - container_of(work, struct tty_struct, buf.work.work); - unsigned long flags; - struct tty_ldisc *disc; - - disc = tty_ldisc_ref(tty); - if (disc == NULL) /* !TTY_LDISC */ - return; - - spin_lock_irqsave(&tty->buf.lock, flags); - - if (!test_and_set_bit(TTY_FLUSHING, &tty->flags)) { - struct tty_buffer *head; - while ((head = tty->buf.head) != NULL) { - int count; - char *char_buf; - unsigned char *flag_buf; - - count = head->commit - head->read; - if (!count) { - if (head->next == NULL) - break; - tty->buf.head = head->next; - tty_buffer_free(tty, head); - continue; - } - /* Ldisc or user is trying to flush the buffers - we are feeding to the ldisc, stop feeding the - line discipline as we want to empty the queue */ - if (test_bit(TTY_FLUSHPENDING, &tty->flags)) - break; - if (!tty->receive_room) { - schedule_delayed_work(&tty->buf.work, 1); - break; - } - if (count > tty->receive_room) - count = tty->receive_room; - char_buf = head->char_buf_ptr + head->read; - flag_buf = head->flag_buf_ptr + head->read; - head->read += count; - spin_unlock_irqrestore(&tty->buf.lock, flags); - disc->ops->receive_buf(tty, char_buf, - flag_buf, count); - spin_lock_irqsave(&tty->buf.lock, flags); - } - clear_bit(TTY_FLUSHING, &tty->flags); - } - - /* We may have a deferred request to flush the input buffer, - if so pull the chain under the lock and empty the queue */ - if (test_bit(TTY_FLUSHPENDING, &tty->flags)) { - __tty_buffer_flush(tty); - clear_bit(TTY_FLUSHPENDING, &tty->flags); - wake_up(&tty->read_wait); - } - spin_unlock_irqrestore(&tty->buf.lock, flags); - - tty_ldisc_deref(disc); -} - -/** - * tty_flush_to_ldisc - * @tty: tty to push - * - * Push the terminal flip buffers to the line discipline. - * - * Must not be called from IRQ context. - */ -void tty_flush_to_ldisc(struct tty_struct *tty) -{ - flush_delayed_work(&tty->buf.work); -} - -/** - * tty_flip_buffer_push - terminal - * @tty: tty to push - * - * Queue a push of the terminal flip buffers to the line discipline. This - * function must not be called from IRQ context if tty->low_latency is set. - * - * In the event of the queue being busy for flipping the work will be - * held off and retried later. - * - * Locking: tty buffer lock. Driver locks in low latency mode. - */ - -void tty_flip_buffer_push(struct tty_struct *tty) -{ - unsigned long flags; - spin_lock_irqsave(&tty->buf.lock, flags); - if (tty->buf.tail != NULL) - tty->buf.tail->commit = tty->buf.tail->used; - spin_unlock_irqrestore(&tty->buf.lock, flags); - - if (tty->low_latency) - flush_to_ldisc(&tty->buf.work.work); - else - schedule_delayed_work(&tty->buf.work, 1); -} -EXPORT_SYMBOL(tty_flip_buffer_push); - -/** - * tty_buffer_init - prepare a tty buffer structure - * @tty: tty to initialise - * - * Set up the initial state of the buffer management for a tty device. - * Must be called before the other tty buffer functions are used. - * - * Locking: none - */ - -void tty_buffer_init(struct tty_struct *tty) -{ - spin_lock_init(&tty->buf.lock); - tty->buf.head = NULL; - tty->buf.tail = NULL; - tty->buf.free = NULL; - tty->buf.memory_used = 0; - INIT_DELAYED_WORK(&tty->buf.work, flush_to_ldisc); -} - diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c deleted file mode 100644 index c05c5af..0000000 --- a/drivers/char/tty_io.c +++ /dev/null @@ -1,3263 +0,0 @@ -/* - * linux/drivers/char/tty_io.c - * - * Copyright (C) 1991, 1992 Linus Torvalds - */ - -/* - * 'tty_io.c' gives an orthogonal feeling to tty's, be they consoles - * or rs-channels. It also implements echoing, cooked mode etc. - * - * Kill-line thanks to John T Kohl, who also corrected VMIN = VTIME = 0. - * - * Modified by Theodore Ts'o, 9/14/92, to dynamically allocate the - * tty_struct and tty_queue structures. Previously there was an array - * of 256 tty_struct's which was statically allocated, and the - * tty_queue structures were allocated at boot time. Both are now - * dynamically allocated only when the tty is open. - * - * Also restructured routines so that there is more of a separation - * between the high-level tty routines (tty_io.c and tty_ioctl.c) and - * the low-level tty routines (serial.c, pty.c, console.c). This - * makes for cleaner and more compact code. -TYT, 9/17/92 - * - * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines - * which can be dynamically activated and de-activated by the line - * discipline handling modules (like SLIP). - * - * NOTE: pay no attention to the line discipline code (yet); its - * interface is still subject to change in this version... - * -- TYT, 1/31/92 - * - * Added functionality to the OPOST tty handling. No delays, but all - * other bits should be there. - * -- Nick Holloway <alfie@dcs.warwick.ac.uk>, 27th May 1993. - * - * Rewrote canonical mode and added more termios flags. - * -- julian@uhunix.uhcc.hawaii.edu (J. Cowley), 13Jan94 - * - * Reorganized FASYNC support so mouse code can share it. - * -- ctm@ardi.com, 9Sep95 - * - * New TIOCLINUX variants added. - * -- mj@k332.feld.cvut.cz, 19-Nov-95 - * - * Restrict vt switching via ioctl() - * -- grif@cs.ucr.edu, 5-Dec-95 - * - * Move console and virtual terminal code to more appropriate files, - * implement CONFIG_VT and generalize console device interface. - * -- Marko Kohtala <Marko.Kohtala@hut.fi>, March 97 - * - * Rewrote tty_init_dev and tty_release_dev to eliminate races. - * -- Bill Hawes <whawes@star.net>, June 97 - * - * Added devfs support. - * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 13-Jan-1998 - * - * Added support for a Unix98-style ptmx device. - * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998 - * - * Reduced memory usage for older ARM systems - * -- Russell King <rmk@arm.linux.org.uk> - * - * Move do_SAK() into process context. Less stack use in devfs functions. - * alloc_tty_struct() always uses kmalloc() - * -- Andrew Morton <andrewm@uow.edu.eu> 17Mar01 - */ - -#include <linux/types.h> -#include <linux/major.h> -#include <linux/errno.h> -#include <linux/signal.h> -#include <linux/fcntl.h> -#include <linux/sched.h> -#include <linux/interrupt.h> -#include <linux/tty.h> -#include <linux/tty_driver.h> -#include <linux/tty_flip.h> -#include <linux/devpts_fs.h> -#include <linux/file.h> -#include <linux/fdtable.h> -#include <linux/console.h> -#include <linux/timer.h> -#include <linux/ctype.h> -#include <linux/kd.h> -#include <linux/mm.h> -#include <linux/string.h> -#include <linux/slab.h> -#include <linux/poll.h> -#include <linux/proc_fs.h> -#include <linux/init.h> -#include <linux/module.h> -#include <linux/smp_lock.h> -#include <linux/device.h> -#include <linux/wait.h> -#include <linux/bitops.h> -#include <linux/delay.h> -#include <linux/seq_file.h> -#include <linux/serial.h> - -#include <linux/uaccess.h> -#include <asm/system.h> - -#include <linux/kbd_kern.h> -#include <linux/vt_kern.h> -#include <linux/selection.h> - -#include <linux/kmod.h> -#include <linux/nsproxy.h> - -#undef TTY_DEBUG_HANGUP - -#define TTY_PARANOIA_CHECK 1 -#define CHECK_TTY_COUNT 1 - -struct ktermios tty_std_termios = { /* for the benefit of tty drivers */ - .c_iflag = ICRNL | IXON, - .c_oflag = OPOST | ONLCR, - .c_cflag = B38400 | CS8 | CREAD | HUPCL, - .c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK | - ECHOCTL | ECHOKE | IEXTEN, - .c_cc = INIT_C_CC, - .c_ispeed = 38400, - .c_ospeed = 38400 -}; - -EXPORT_SYMBOL(tty_std_termios); - -/* This list gets poked at by procfs and various bits of boot up code. This - could do with some rationalisation such as pulling the tty proc function - into this file */ - -LIST_HEAD(tty_drivers); /* linked list of tty drivers */ - -/* Mutex to protect creating and releasing a tty. This is shared with - vt.c for deeply disgusting hack reasons */ -DEFINE_MUTEX(tty_mutex); -EXPORT_SYMBOL(tty_mutex); - -/* Spinlock to protect the tty->tty_files list */ -DEFINE_SPINLOCK(tty_files_lock); - -static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *); -static ssize_t tty_write(struct file *, const char __user *, size_t, loff_t *); -ssize_t redirected_tty_write(struct file *, const char __user *, - size_t, loff_t *); -static unsigned int tty_poll(struct file *, poll_table *); -static int tty_open(struct inode *, struct file *); -long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); -#ifdef CONFIG_COMPAT -static long tty_compat_ioctl(struct file *file, unsigned int cmd, - unsigned long arg); -#else -#define tty_compat_ioctl NULL -#endif -static int __tty_fasync(int fd, struct file *filp, int on); -static int tty_fasync(int fd, struct file *filp, int on); -static void release_tty(struct tty_struct *tty, int idx); -static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty); -static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty); - -/** - * alloc_tty_struct - allocate a tty object - * - * Return a new empty tty structure. The data fields have not - * been initialized in any way but has been zeroed - * - * Locking: none - */ - -struct tty_struct *alloc_tty_struct(void) -{ - return kzalloc(sizeof(struct tty_struct), GFP_KERNEL); -} - -/** - * free_tty_struct - free a disused tty - * @tty: tty struct to free - * - * Free the write buffers, tty queue and tty memory itself. - * - * Locking: none. Must be called after tty is definitely unused - */ - -void free_tty_struct(struct tty_struct *tty) -{ - if (tty->dev) - put_device(tty->dev); - kfree(tty->write_buf); - tty_buffer_free_all(tty); - kfree(tty); -} - -static inline struct tty_struct *file_tty(struct file *file) -{ - return ((struct tty_file_private *)file->private_data)->tty; -} - -/* Associate a new file with the tty structure */ -int tty_add_file(struct tty_struct *tty, struct file *file) -{ - struct tty_file_private *priv; - - priv = kmalloc(sizeof(*priv), GFP_KERNEL); - if (!priv) - return -ENOMEM; - - priv->tty = tty; - priv->file = file; - file->private_data = priv; - - spin_lock(&tty_files_lock); - list_add(&priv->list, &tty->tty_files); - spin_unlock(&tty_files_lock); - - return 0; -} - -/* Delete file from its tty */ -void tty_del_file(struct file *file) -{ - struct tty_file_private *priv = file->private_data; - - spin_lock(&tty_files_lock); - list_del(&priv->list); - spin_unlock(&tty_files_lock); - file->private_data = NULL; - kfree(priv); -} - - -#define TTY_NUMBER(tty) ((tty)->index + (tty)->driver->name_base) - -/** - * tty_name - return tty naming - * @tty: tty structure - * @buf: buffer for output - * - * Convert a tty structure into a name. The name reflects the kernel - * naming policy and if udev is in use may not reflect user space - * - * Locking: none - */ - -char *tty_name(struct tty_struct *tty, char *buf) -{ - if (!tty) /* Hmm. NULL pointer. That's fun. */ - strcpy(buf, "NULL tty"); - else - strcpy(buf, tty->name); - return buf; -} - -EXPORT_SYMBOL(tty_name); - -int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, - const char *routine) -{ -#ifdef TTY_PARANOIA_CHECK - if (!tty) { - printk(KERN_WARNING - "null TTY for (%d:%d) in %s\n", - imajor(inode), iminor(inode), routine); - return 1; - } - if (tty->magic != TTY_MAGIC) { - printk(KERN_WARNING - "bad magic number for tty struct (%d:%d) in %s\n", - imajor(inode), iminor(inode), routine); - return 1; - } -#endif - return 0; -} - -static int check_tty_count(struct tty_struct *tty, const char *routine) -{ -#ifdef CHECK_TTY_COUNT - struct list_head *p; - int count = 0; - - spin_lock(&tty_files_lock); - list_for_each(p, &tty->tty_files) { - count++; - } - spin_unlock(&tty_files_lock); - if (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->driver->subtype == PTY_TYPE_SLAVE && - tty->link && tty->link->count) - count++; - if (tty->count != count) { - printk(KERN_WARNING "Warning: dev (%s) tty->count(%d) " - "!= #fd's(%d) in %s\n", - tty->name, tty->count, count, routine); - return count; - } -#endif - return 0; -} - -/** - * get_tty_driver - find device of a tty - * @dev_t: device identifier - * @index: returns the index of the tty - * - * This routine returns a tty driver structure, given a device number - * and also passes back the index number. - * - * Locking: caller must hold tty_mutex - */ - -static struct tty_driver *get_tty_driver(dev_t device, int *index) -{ - struct tty_driver *p; - - list_for_each_entry(p, &tty_drivers, tty_drivers) { - dev_t base = MKDEV(p->major, p->minor_start); - if (device < base || device >= base + p->num) - continue; - *index = device - base; - return tty_driver_kref_get(p); - } - return NULL; -} - -#ifdef CONFIG_CONSOLE_POLL - -/** - * tty_find_polling_driver - find device of a polled tty - * @name: name string to match - * @line: pointer to resulting tty line nr - * - * This routine returns a tty driver structure, given a name - * and the condition that the tty driver is capable of polled - * operation. - */ -struct tty_driver *tty_find_polling_driver(char *name, int *line) -{ - struct tty_driver *p, *res = NULL; - int tty_line = 0; - int len; - char *str, *stp; - - for (str = name; *str; str++) - if ((*str >= '0' && *str <= '9') || *str == ',') - break; - if (!*str) - return NULL; - - len = str - name; - tty_line = simple_strtoul(str, &str, 10); - - mutex_lock(&tty_mutex); - /* Search through the tty devices to look for a match */ - list_for_each_entry(p, &tty_drivers, tty_drivers) { - if (strncmp(name, p->name, len) != 0) - continue; - stp = str; - if (*stp == ',') - stp++; - if (*stp == '\0') - stp = NULL; - - if (tty_line >= 0 && tty_line < p->num && p->ops && - p->ops->poll_init && !p->ops->poll_init(p, tty_line, stp)) { - res = tty_driver_kref_get(p); - *line = tty_line; - break; - } - } - mutex_unlock(&tty_mutex); - - return res; -} -EXPORT_SYMBOL_GPL(tty_find_polling_driver); -#endif - -/** - * tty_check_change - check for POSIX terminal changes - * @tty: tty to check - * - * If we try to write to, or set the state of, a terminal and we're - * not in the foreground, send a SIGTTOU. If the signal is blocked or - * ignored, go ahead and perform the operation. (POSIX 7.2) - * - * Locking: ctrl_lock - */ - -int tty_check_change(struct tty_struct *tty) -{ - unsigned long flags; - int ret = 0; - - if (current->signal->tty != tty) - return 0; - - spin_lock_irqsave(&tty->ctrl_lock, flags); - - if (!tty->pgrp) { - printk(KERN_WARNING "tty_check_change: tty->pgrp == NULL!\n"); - goto out_unlock; - } - if (task_pgrp(current) == tty->pgrp) - goto out_unlock; - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - if (is_ignored(SIGTTOU)) - goto out; - if (is_current_pgrp_orphaned()) { - ret = -EIO; - goto out; - } - kill_pgrp(task_pgrp(current), SIGTTOU, 1); - set_thread_flag(TIF_SIGPENDING); - ret = -ERESTARTSYS; -out: - return ret; -out_unlock: - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - return ret; -} - -EXPORT_SYMBOL(tty_check_change); - -static ssize_t hung_up_tty_read(struct file *file, char __user *buf, - size_t count, loff_t *ppos) -{ - return 0; -} - -static ssize_t hung_up_tty_write(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) -{ - return -EIO; -} - -/* No kernel lock held - none needed ;) */ -static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait) -{ - return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM; -} - -static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - return cmd == TIOCSPGRP ? -ENOTTY : -EIO; -} - -static long hung_up_tty_compat_ioctl(struct file *file, - unsigned int cmd, unsigned long arg) -{ - return cmd == TIOCSPGRP ? -ENOTTY : -EIO; -} - -static const struct file_operations tty_fops = { - .llseek = no_llseek, - .read = tty_read, - .write = tty_write, - .poll = tty_poll, - .unlocked_ioctl = tty_ioctl, - .compat_ioctl = tty_compat_ioctl, - .open = tty_open, - .release = tty_release, - .fasync = tty_fasync, -}; - -static const struct file_operations console_fops = { - .llseek = no_llseek, - .read = tty_read, - .write = redirected_tty_write, - .poll = tty_poll, - .unlocked_ioctl = tty_ioctl, - .compat_ioctl = tty_compat_ioctl, - .open = tty_open, - .release = tty_release, - .fasync = tty_fasync, -}; - -static const struct file_operations hung_up_tty_fops = { - .llseek = no_llseek, - .read = hung_up_tty_read, - .write = hung_up_tty_write, - .poll = hung_up_tty_poll, - .unlocked_ioctl = hung_up_tty_ioctl, - .compat_ioctl = hung_up_tty_compat_ioctl, - .release = tty_release, -}; - -static DEFINE_SPINLOCK(redirect_lock); -static struct file *redirect; - -/** - * tty_wakeup - request more data - * @tty: terminal - * - * Internal and external helper for wakeups of tty. This function - * informs the line discipline if present that the driver is ready - * to receive more output data. - */ - -void tty_wakeup(struct tty_struct *tty) -{ - struct tty_ldisc *ld; - - if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) { - ld = tty_ldisc_ref(tty); - if (ld) { - if (ld->ops->write_wakeup) - ld->ops->write_wakeup(tty); - tty_ldisc_deref(ld); - } - } - wake_up_interruptible_poll(&tty->write_wait, POLLOUT); -} - -EXPORT_SYMBOL_GPL(tty_wakeup); - -/** - * __tty_hangup - actual handler for hangup events - * @work: tty device - * - * This can be called by the "eventd" kernel thread. That is process - * synchronous but doesn't hold any locks, so we need to make sure we - * have the appropriate locks for what we're doing. - * - * The hangup event clears any pending redirections onto the hung up - * device. It ensures future writes will error and it does the needed - * line discipline hangup and signal delivery. The tty object itself - * remains intact. - * - * Locking: - * BTM - * redirect lock for undoing redirection - * file list lock for manipulating list of ttys - * tty_ldisc_lock from called functions - * termios_mutex resetting termios data - * tasklist_lock to walk task list for hangup event - * ->siglock to protect ->signal/->sighand - */ -void __tty_hangup(struct tty_struct *tty) -{ - struct file *cons_filp = NULL; - struct file *filp, *f = NULL; - struct task_struct *p; - struct tty_file_private *priv; - int closecount = 0, n; - unsigned long flags; - int refs = 0; - - if (!tty) - return; - - - spin_lock(&redirect_lock); - if (redirect && file_tty(redirect) == tty) { - f = redirect; - redirect = NULL; - } - spin_unlock(&redirect_lock); - - tty_lock(); - - /* inuse_filps is protected by the single tty lock, - this really needs to change if we want to flush the - workqueue with the lock held */ - check_tty_count(tty, "tty_hangup"); - - spin_lock(&tty_files_lock); - /* This breaks for file handles being sent over AF_UNIX sockets ? */ - list_for_each_entry(priv, &tty->tty_files, list) { - filp = priv->file; - if (filp->f_op->write == redirected_tty_write) - cons_filp = filp; - if (filp->f_op->write != tty_write) - continue; - closecount++; - __tty_fasync(-1, filp, 0); /* can't block */ - filp->f_op = &hung_up_tty_fops; - } - spin_unlock(&tty_files_lock); - - tty_ldisc_hangup(tty); - - read_lock(&tasklist_lock); - if (tty->session) { - do_each_pid_task(tty->session, PIDTYPE_SID, p) { - spin_lock_irq(&p->sighand->siglock); - if (p->signal->tty == tty) { - p->signal->tty = NULL; - /* We defer the dereferences outside fo - the tasklist lock */ - refs++; - } - if (!p->signal->leader) { - spin_unlock_irq(&p->sighand->siglock); - continue; - } - __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p); - __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p); - put_pid(p->signal->tty_old_pgrp); /* A noop */ - spin_lock_irqsave(&tty->ctrl_lock, flags); - if (tty->pgrp) - p->signal->tty_old_pgrp = get_pid(tty->pgrp); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - spin_unlock_irq(&p->sighand->siglock); - } while_each_pid_task(tty->session, PIDTYPE_SID, p); - } - read_unlock(&tasklist_lock); - - spin_lock_irqsave(&tty->ctrl_lock, flags); - clear_bit(TTY_THROTTLED, &tty->flags); - clear_bit(TTY_PUSH, &tty->flags); - clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); - put_pid(tty->session); - put_pid(tty->pgrp); - tty->session = NULL; - tty->pgrp = NULL; - tty->ctrl_status = 0; - set_bit(TTY_HUPPED, &tty->flags); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - - /* Account for the p->signal references we killed */ - while (refs--) - tty_kref_put(tty); - - /* - * If one of the devices matches a console pointer, we - * cannot just call hangup() because that will cause - * tty->count and state->count to go out of sync. - * So we just call close() the right number of times. - */ - if (cons_filp) { - if (tty->ops->close) - for (n = 0; n < closecount; n++) - tty->ops->close(tty, cons_filp); - } else if (tty->ops->hangup) - (tty->ops->hangup)(tty); - /* - * We don't want to have driver/ldisc interactions beyond - * the ones we did here. The driver layer expects no - * calls after ->hangup() from the ldisc side. However we - * can't yet guarantee all that. - */ - set_bit(TTY_HUPPED, &tty->flags); - tty_ldisc_enable(tty); - - tty_unlock(); - - if (f) - fput(f); -} - -static void do_tty_hangup(struct work_struct *work) -{ - struct tty_struct *tty = - container_of(work, struct tty_struct, hangup_work); - - __tty_hangup(tty); -} - -/** - * tty_hangup - trigger a hangup event - * @tty: tty to hangup - * - * A carrier loss (virtual or otherwise) has occurred on this like - * schedule a hangup sequence to run after this event. - */ - -void tty_hangup(struct tty_struct *tty) -{ -#ifdef TTY_DEBUG_HANGUP - char buf[64]; - printk(KERN_DEBUG "%s hangup...\n", tty_name(tty, buf)); -#endif - schedule_work(&tty->hangup_work); -} - -EXPORT_SYMBOL(tty_hangup); - -/** - * tty_vhangup - process vhangup - * @tty: tty to hangup - * - * The user has asked via system call for the terminal to be hung up. - * We do this synchronously so that when the syscall returns the process - * is complete. That guarantee is necessary for security reasons. - */ - -void tty_vhangup(struct tty_struct *tty) -{ -#ifdef TTY_DEBUG_HANGUP - char buf[64]; - - printk(KERN_DEBUG "%s vhangup...\n", tty_name(tty, buf)); -#endif - __tty_hangup(tty); -} - -EXPORT_SYMBOL(tty_vhangup); - - -/** - * tty_vhangup_self - process vhangup for own ctty - * - * Perform a vhangup on the current controlling tty - */ - -void tty_vhangup_self(void) -{ - struct tty_struct *tty; - - tty = get_current_tty(); - if (tty) { - tty_vhangup(tty); - tty_kref_put(tty); - } -} - -/** - * tty_hung_up_p - was tty hung up - * @filp: file pointer of tty - * - * Return true if the tty has been subject to a vhangup or a carrier - * loss - */ - -int tty_hung_up_p(struct file *filp) -{ - return (filp->f_op == &hung_up_tty_fops); -} - -EXPORT_SYMBOL(tty_hung_up_p); - -static void session_clear_tty(struct pid *session) -{ - struct task_struct *p; - do_each_pid_task(session, PIDTYPE_SID, p) { - proc_clear_tty(p); - } while_each_pid_task(session, PIDTYPE_SID, p); -} - -/** - * disassociate_ctty - disconnect controlling tty - * @on_exit: true if exiting so need to "hang up" the session - * - * This function is typically called only by the session leader, when - * it wants to disassociate itself from its controlling tty. - * - * It performs the following functions: - * (1) Sends a SIGHUP and SIGCONT to the foreground process group - * (2) Clears the tty from being controlling the session - * (3) Clears the controlling tty for all processes in the - * session group. - * - * The argument on_exit is set to 1 if called when a process is - * exiting; it is 0 if called by the ioctl TIOCNOTTY. - * - * Locking: - * BTM is taken for hysterical raisins, and held when - * called from no_tty(). - * tty_mutex is taken to protect tty - * ->siglock is taken to protect ->signal/->sighand - * tasklist_lock is taken to walk process list for sessions - * ->siglock is taken to protect ->signal/->sighand - */ - -void disassociate_ctty(int on_exit) -{ - struct tty_struct *tty; - struct pid *tty_pgrp = NULL; - - if (!current->signal->leader) - return; - - tty = get_current_tty(); - if (tty) { - tty_pgrp = get_pid(tty->pgrp); - if (on_exit) { - if (tty->driver->type != TTY_DRIVER_TYPE_PTY) - tty_vhangup(tty); - } - tty_kref_put(tty); - } else if (on_exit) { - struct pid *old_pgrp; - spin_lock_irq(¤t->sighand->siglock); - old_pgrp = current->signal->tty_old_pgrp; - current->signal->tty_old_pgrp = NULL; - spin_unlock_irq(¤t->sighand->siglock); - if (old_pgrp) { - kill_pgrp(old_pgrp, SIGHUP, on_exit); - kill_pgrp(old_pgrp, SIGCONT, on_exit); - put_pid(old_pgrp); - } - return; - } - if (tty_pgrp) { - kill_pgrp(tty_pgrp, SIGHUP, on_exit); - if (!on_exit) - kill_pgrp(tty_pgrp, SIGCONT, on_exit); - put_pid(tty_pgrp); - } - - spin_lock_irq(¤t->sighand->siglock); - put_pid(current->signal->tty_old_pgrp); - current->signal->tty_old_pgrp = NULL; - spin_unlock_irq(¤t->sighand->siglock); - - tty = get_current_tty(); - if (tty) { - unsigned long flags; - spin_lock_irqsave(&tty->ctrl_lock, flags); - put_pid(tty->session); - put_pid(tty->pgrp); - tty->session = NULL; - tty->pgrp = NULL; - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - tty_kref_put(tty); - } else { -#ifdef TTY_DEBUG_HANGUP - printk(KERN_DEBUG "error attempted to write to tty [0x%p]" - " = NULL", tty); -#endif - } - - /* Now clear signal->tty under the lock */ - read_lock(&tasklist_lock); - session_clear_tty(task_session(current)); - read_unlock(&tasklist_lock); -} - -/** - * - * no_tty - Ensure the current process does not have a controlling tty - */ -void no_tty(void) -{ - struct task_struct *tsk = current; - tty_lock(); - disassociate_ctty(0); - tty_unlock(); - proc_clear_tty(tsk); -} - - -/** - * stop_tty - propagate flow control - * @tty: tty to stop - * - * Perform flow control to the driver. For PTY/TTY pairs we - * must also propagate the TIOCKPKT status. May be called - * on an already stopped device and will not re-call the driver - * method. - * - * This functionality is used by both the line disciplines for - * halting incoming flow and by the driver. It may therefore be - * called from any context, may be under the tty atomic_write_lock - * but not always. - * - * Locking: - * Uses the tty control lock internally - */ - -void stop_tty(struct tty_struct *tty) -{ - unsigned long flags; - spin_lock_irqsave(&tty->ctrl_lock, flags); - if (tty->stopped) { - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - return; - } - tty->stopped = 1; - if (tty->link && tty->link->packet) { - tty->ctrl_status &= ~TIOCPKT_START; - tty->ctrl_status |= TIOCPKT_STOP; - wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); - } - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - if (tty->ops->stop) - (tty->ops->stop)(tty); -} - -EXPORT_SYMBOL(stop_tty); - -/** - * start_tty - propagate flow control - * @tty: tty to start - * - * Start a tty that has been stopped if at all possible. Perform - * any necessary wakeups and propagate the TIOCPKT status. If this - * is the tty was previous stopped and is being started then the - * driver start method is invoked and the line discipline woken. - * - * Locking: - * ctrl_lock - */ - -void start_tty(struct tty_struct *tty) -{ - unsigned long flags; - spin_lock_irqsave(&tty->ctrl_lock, flags); - if (!tty->stopped || tty->flow_stopped) { - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - return; - } - tty->stopped = 0; - if (tty->link && tty->link->packet) { - tty->ctrl_status &= ~TIOCPKT_STOP; - tty->ctrl_status |= TIOCPKT_START; - wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); - } - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - if (tty->ops->start) - (tty->ops->start)(tty); - /* If we have a running line discipline it may need kicking */ - tty_wakeup(tty); -} - -EXPORT_SYMBOL(start_tty); - -/** - * tty_read - read method for tty device files - * @file: pointer to tty file - * @buf: user buffer - * @count: size of user buffer - * @ppos: unused - * - * Perform the read system call function on this terminal device. Checks - * for hung up devices before calling the line discipline method. - * - * Locking: - * Locks the line discipline internally while needed. Multiple - * read calls may be outstanding in parallel. - */ - -static ssize_t tty_read(struct file *file, char __user *buf, size_t count, - loff_t *ppos) -{ - int i; - struct inode *inode = file->f_path.dentry->d_inode; - struct tty_struct *tty = file_tty(file); - struct tty_ldisc *ld; - - if (tty_paranoia_check(tty, inode, "tty_read")) - return -EIO; - if (!tty || (test_bit(TTY_IO_ERROR, &tty->flags))) - return -EIO; - - /* We want to wait for the line discipline to sort out in this - situation */ - ld = tty_ldisc_ref_wait(tty); - if (ld->ops->read) - i = (ld->ops->read)(tty, file, buf, count); - else - i = -EIO; - tty_ldisc_deref(ld); - if (i > 0) - inode->i_atime = current_fs_time(inode->i_sb); - return i; -} - -void tty_write_unlock(struct tty_struct *tty) -{ - mutex_unlock(&tty->atomic_write_lock); - wake_up_interruptible_poll(&tty->write_wait, POLLOUT); -} - -int tty_write_lock(struct tty_struct *tty, int ndelay) -{ - if (!mutex_trylock(&tty->atomic_write_lock)) { - if (ndelay) - return -EAGAIN; - if (mutex_lock_interruptible(&tty->atomic_write_lock)) - return -ERESTARTSYS; - } - return 0; -} - -/* - * Split writes up in sane blocksizes to avoid - * denial-of-service type attacks - */ -static inline ssize_t do_tty_write( - ssize_t (*write)(struct tty_struct *, struct file *, const unsigned char *, size_t), - struct tty_struct *tty, - struct file *file, - const char __user *buf, - size_t count) -{ - ssize_t ret, written = 0; - unsigned int chunk; - - ret = tty_write_lock(tty, file->f_flags & O_NDELAY); - if (ret < 0) - return ret; - - /* - * We chunk up writes into a temporary buffer. This - * simplifies low-level drivers immensely, since they - * don't have locking issues and user mode accesses. - * - * But if TTY_NO_WRITE_SPLIT is set, we should use a - * big chunk-size.. - * - * The default chunk-size is 2kB, because the NTTY - * layer has problems with bigger chunks. It will - * claim to be able to handle more characters than - * it actually does. - * - * FIXME: This can probably go away now except that 64K chunks - * are too likely to fail unless switched to vmalloc... - */ - chunk = 2048; - if (test_bit(TTY_NO_WRITE_SPLIT, &tty->flags)) - chunk = 65536; - if (count < chunk) - chunk = count; - - /* write_buf/write_cnt is protected by the atomic_write_lock mutex */ - if (tty->write_cnt < chunk) { - unsigned char *buf_chunk; - - if (chunk < 1024) - chunk = 1024; - - buf_chunk = kmalloc(chunk, GFP_KERNEL); - if (!buf_chunk) { - ret = -ENOMEM; - goto out; - } - kfree(tty->write_buf); - tty->write_cnt = chunk; - tty->write_buf = buf_chunk; - } - - /* Do the write .. */ - for (;;) { - size_t size = count; - if (size > chunk) - size = chunk; - ret = -EFAULT; - if (copy_from_user(tty->write_buf, buf, size)) - break; - ret = write(tty, file, tty->write_buf, size); - if (ret <= 0) - break; - written += ret; - buf += ret; - count -= ret; - if (!count) - break; - ret = -ERESTARTSYS; - if (signal_pending(current)) - break; - cond_resched(); - } - if (written) { - struct inode *inode = file->f_path.dentry->d_inode; - inode->i_mtime = current_fs_time(inode->i_sb); - ret = written; - } -out: - tty_write_unlock(tty); - return ret; -} - -/** - * tty_write_message - write a message to a certain tty, not just the console. - * @tty: the destination tty_struct - * @msg: the message to write - * - * This is used for messages that need to be redirected to a specific tty. - * We don't put it into the syslog queue right now maybe in the future if - * really needed. - * - * We must still hold the BTM and test the CLOSING flag for the moment. - */ - -void tty_write_message(struct tty_struct *tty, char *msg) -{ - if (tty) { - mutex_lock(&tty->atomic_write_lock); - tty_lock(); - if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) { - tty_unlock(); - tty->ops->write(tty, msg, strlen(msg)); - } else - tty_unlock(); - tty_write_unlock(tty); - } - return; -} - - -/** - * tty_write - write method for tty device file - * @file: tty file pointer - * @buf: user data to write - * @count: bytes to write - * @ppos: unused - * - * Write data to a tty device via the line discipline. - * - * Locking: - * Locks the line discipline as required - * Writes to the tty driver are serialized by the atomic_write_lock - * and are then processed in chunks to the device. The line discipline - * write method will not be invoked in parallel for each device. - */ - -static ssize_t tty_write(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) -{ - struct inode *inode = file->f_path.dentry->d_inode; - struct tty_struct *tty = file_tty(file); - struct tty_ldisc *ld; - ssize_t ret; - - if (tty_paranoia_check(tty, inode, "tty_write")) - return -EIO; - if (!tty || !tty->ops->write || - (test_bit(TTY_IO_ERROR, &tty->flags))) - return -EIO; - /* Short term debug to catch buggy drivers */ - if (tty->ops->write_room == NULL) - printk(KERN_ERR "tty driver %s lacks a write_room method.\n", - tty->driver->name); - ld = tty_ldisc_ref_wait(tty); - if (!ld->ops->write) - ret = -EIO; - else - ret = do_tty_write(ld->ops->write, tty, file, buf, count); - tty_ldisc_deref(ld); - return ret; -} - -ssize_t redirected_tty_write(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) -{ - struct file *p = NULL; - - spin_lock(&redirect_lock); - if (redirect) { - get_file(redirect); - p = redirect; - } - spin_unlock(&redirect_lock); - - if (p) { - ssize_t res; - res = vfs_write(p, buf, count, &p->f_pos); - fput(p); - return res; - } - return tty_write(file, buf, count, ppos); -} - -static char ptychar[] = "pqrstuvwxyzabcde"; - -/** - * pty_line_name - generate name for a pty - * @driver: the tty driver in use - * @index: the minor number - * @p: output buffer of at least 6 bytes - * - * Generate a name from a driver reference and write it to the output - * buffer. - * - * Locking: None - */ -static void pty_line_name(struct tty_driver *driver, int index, char *p) -{ - int i = index + driver->name_base; - /* ->name is initialized to "ttyp", but "tty" is expected */ - sprintf(p, "%s%c%x", - driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name, - ptychar[i >> 4 & 0xf], i & 0xf); -} - -/** - * tty_line_name - generate name for a tty - * @driver: the tty driver in use - * @index: the minor number - * @p: output buffer of at least 7 bytes - * - * Generate a name from a driver reference and write it to the output - * buffer. - * - * Locking: None - */ -static void tty_line_name(struct tty_driver *driver, int index, char *p) -{ - sprintf(p, "%s%d", driver->name, index + driver->name_base); -} - -/** - * tty_driver_lookup_tty() - find an existing tty, if any - * @driver: the driver for the tty - * @idx: the minor number - * - * Return the tty, if found or ERR_PTR() otherwise. - * - * Locking: tty_mutex must be held. If tty is found, the mutex must - * be held until the 'fast-open' is also done. Will change once we - * have refcounting in the driver and per driver locking - */ -static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, - struct inode *inode, int idx) -{ - struct tty_struct *tty; - - if (driver->ops->lookup) - return driver->ops->lookup(driver, inode, idx); - - tty = driver->ttys[idx]; - return tty; -} - -/** - * tty_init_termios - helper for termios setup - * @tty: the tty to set up - * - * Initialise the termios structures for this tty. Thus runs under - * the tty_mutex currently so we can be relaxed about ordering. - */ - -int tty_init_termios(struct tty_struct *tty) -{ - struct ktermios *tp; - int idx = tty->index; - - tp = tty->driver->termios[idx]; - if (tp == NULL) { - tp = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL); - if (tp == NULL) - return -ENOMEM; - memcpy(tp, &tty->driver->init_termios, - sizeof(struct ktermios)); - tty->driver->termios[idx] = tp; - } - tty->termios = tp; - tty->termios_locked = tp + 1; - - /* Compatibility until drivers always set this */ - tty->termios->c_ispeed = tty_termios_input_baud_rate(tty->termios); - tty->termios->c_ospeed = tty_termios_baud_rate(tty->termios); - return 0; -} -EXPORT_SYMBOL_GPL(tty_init_termios); - -/** - * tty_driver_install_tty() - install a tty entry in the driver - * @driver: the driver for the tty - * @tty: the tty - * - * Install a tty object into the driver tables. The tty->index field - * will be set by the time this is called. This method is responsible - * for ensuring any need additional structures are allocated and - * configured. - * - * Locking: tty_mutex for now - */ -static int tty_driver_install_tty(struct tty_driver *driver, - struct tty_struct *tty) -{ - int idx = tty->index; - int ret; - - if (driver->ops->install) { - ret = driver->ops->install(driver, tty); - return ret; - } - - if (tty_init_termios(tty) == 0) { - tty_driver_kref_get(driver); - tty->count++; - driver->ttys[idx] = tty; - return 0; - } - return -ENOMEM; -} - -/** - * tty_driver_remove_tty() - remove a tty from the driver tables - * @driver: the driver for the tty - * @idx: the minor number - * - * Remvoe a tty object from the driver tables. The tty->index field - * will be set by the time this is called. - * - * Locking: tty_mutex for now - */ -static void tty_driver_remove_tty(struct tty_driver *driver, - struct tty_struct *tty) -{ - if (driver->ops->remove) - driver->ops->remove(driver, tty); - else - driver->ttys[tty->index] = NULL; -} - -/* - * tty_reopen() - fast re-open of an open tty - * @tty - the tty to open - * - * Return 0 on success, -errno on error. - * - * Locking: tty_mutex must be held from the time the tty was found - * till this open completes. - */ -static int tty_reopen(struct tty_struct *tty) -{ - struct tty_driver *driver = tty->driver; - - if (test_bit(TTY_CLOSING, &tty->flags)) - return -EIO; - - if (driver->type == TTY_DRIVER_TYPE_PTY && - driver->subtype == PTY_TYPE_MASTER) { - /* - * special case for PTY masters: only one open permitted, - * and the slave side open count is incremented as well. - */ - if (tty->count) - return -EIO; - - tty->link->count++; - } - tty->count++; - tty->driver = driver; /* N.B. why do this every time?? */ - - mutex_lock(&tty->ldisc_mutex); - WARN_ON(!test_bit(TTY_LDISC, &tty->flags)); - mutex_unlock(&tty->ldisc_mutex); - - return 0; -} - -/** - * tty_init_dev - initialise a tty device - * @driver: tty driver we are opening a device on - * @idx: device index - * @ret_tty: returned tty structure - * @first_ok: ok to open a new device (used by ptmx) - * - * Prepare a tty device. This may not be a "new" clean device but - * could also be an active device. The pty drivers require special - * handling because of this. - * - * Locking: - * The function is called under the tty_mutex, which - * protects us from the tty struct or driver itself going away. - * - * On exit the tty device has the line discipline attached and - * a reference count of 1. If a pair was created for pty/tty use - * and the other was a pty master then it too has a reference count of 1. - * - * WSH 06/09/97: Rewritten to remove races and properly clean up after a - * failed open. The new code protects the open with a mutex, so it's - * really quite straightforward. The mutex locking can probably be - * relaxed for the (most common) case of reopening a tty. - */ - -struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx, - int first_ok) -{ - struct tty_struct *tty; - int retval; - - /* Check if pty master is being opened multiple times */ - if (driver->subtype == PTY_TYPE_MASTER && - (driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok) { - return ERR_PTR(-EIO); - } - - /* - * First time open is complex, especially for PTY devices. - * This code guarantees that either everything succeeds and the - * TTY is ready for operation, or else the table slots are vacated - * and the allocated memory released. (Except that the termios - * and locked termios may be retained.) - */ - - if (!try_module_get(driver->owner)) - return ERR_PTR(-ENODEV); - - tty = alloc_tty_struct(); - if (!tty) - goto fail_no_mem; - initialize_tty_struct(tty, driver, idx); - - retval = tty_driver_install_tty(driver, tty); - if (retval < 0) { - free_tty_struct(tty); - module_put(driver->owner); - return ERR_PTR(retval); - } - - /* - * Structures all installed ... call the ldisc open routines. - * If we fail here just call release_tty to clean up. No need - * to decrement the use counts, as release_tty doesn't care. - */ - retval = tty_ldisc_setup(tty, tty->link); - if (retval) - goto release_mem_out; - return tty; - -fail_no_mem: - module_put(driver->owner); - return ERR_PTR(-ENOMEM); - - /* call the tty release_tty routine to clean out this slot */ -release_mem_out: - if (printk_ratelimit()) - printk(KERN_INFO "tty_init_dev: ldisc open failed, " - "clearing slot %d\n", idx); - release_tty(tty, idx); - return ERR_PTR(retval); -} - -void tty_free_termios(struct tty_struct *tty) -{ - struct ktermios *tp; - int idx = tty->index; - /* Kill this flag and push into drivers for locking etc */ - if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) { - /* FIXME: Locking on ->termios array */ - tp = tty->termios; - tty->driver->termios[idx] = NULL; - kfree(tp); - } -} -EXPORT_SYMBOL(tty_free_termios); - -void tty_shutdown(struct tty_struct *tty) -{ - tty_driver_remove_tty(tty->driver, tty); - tty_free_termios(tty); -} -EXPORT_SYMBOL(tty_shutdown); - -/** - * release_one_tty - release tty structure memory - * @kref: kref of tty we are obliterating - * - * Releases memory associated with a tty structure, and clears out the - * driver table slots. This function is called when a device is no longer - * in use. It also gets called when setup of a device fails. - * - * Locking: - * tty_mutex - sometimes only - * takes the file list lock internally when working on the list - * of ttys that the driver keeps. - * - * This method gets called from a work queue so that the driver private - * cleanup ops can sleep (needed for USB at least) - */ -static void release_one_tty(struct work_struct *work) -{ - struct tty_struct *tty = - container_of(work, struct tty_struct, hangup_work); - struct tty_driver *driver = tty->driver; - - if (tty->ops->cleanup) - tty->ops->cleanup(tty); - - tty->magic = 0; - tty_driver_kref_put(driver); - module_put(driver->owner); - - spin_lock(&tty_files_lock); - list_del_init(&tty->tty_files); - spin_unlock(&tty_files_lock); - - put_pid(tty->pgrp); - put_pid(tty->session); - free_tty_struct(tty); -} - -static void queue_release_one_tty(struct kref *kref) -{ - struct tty_struct *tty = container_of(kref, struct tty_struct, kref); - - if (tty->ops->shutdown) - tty->ops->shutdown(tty); - else - tty_shutdown(tty); - - /* The hangup queue is now free so we can reuse it rather than - waste a chunk of memory for each port */ - INIT_WORK(&tty->hangup_work, release_one_tty); - schedule_work(&tty->hangup_work); -} - -/** - * tty_kref_put - release a tty kref - * @tty: tty device - * - * Release a reference to a tty device and if need be let the kref - * layer destruct the object for us - */ - -void tty_kref_put(struct tty_struct *tty) -{ - if (tty) - kref_put(&tty->kref, queue_release_one_tty); -} -EXPORT_SYMBOL(tty_kref_put); - -/** - * release_tty - release tty structure memory - * - * Release both @tty and a possible linked partner (think pty pair), - * and decrement the refcount of the backing module. - * - * Locking: - * tty_mutex - sometimes only - * takes the file list lock internally when working on the list - * of ttys that the driver keeps. - * FIXME: should we require tty_mutex is held here ?? - * - */ -static void release_tty(struct tty_struct *tty, int idx) -{ - /* This should always be true but check for the moment */ - WARN_ON(tty->index != idx); - - if (tty->link) - tty_kref_put(tty->link); - tty_kref_put(tty); -} - -/** - * tty_release - vfs callback for close - * @inode: inode of tty - * @filp: file pointer for handle to tty - * - * Called the last time each file handle is closed that references - * this tty. There may however be several such references. - * - * Locking: - * Takes bkl. See tty_release_dev - * - * Even releasing the tty structures is a tricky business.. We have - * to be very careful that the structures are all released at the - * same time, as interrupts might otherwise get the wrong pointers. - * - * WSH 09/09/97: rewritten to avoid some nasty race conditions that could - * lead to double frees or releasing memory still in use. - */ - -int tty_release(struct inode *inode, struct file *filp) -{ - struct tty_struct *tty = file_tty(filp); - struct tty_struct *o_tty; - int pty_master, tty_closing, o_tty_closing, do_sleep; - int devpts; - int idx; - char buf[64]; - - if (tty_paranoia_check(tty, inode, "tty_release_dev")) - return 0; - - tty_lock(); - check_tty_count(tty, "tty_release_dev"); - - __tty_fasync(-1, filp, 0); - - idx = tty->index; - pty_master = (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->driver->subtype == PTY_TYPE_MASTER); - devpts = (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) != 0; - o_tty = tty->link; - -#ifdef TTY_PARANOIA_CHECK - if (idx < 0 || idx >= tty->driver->num) { - printk(KERN_DEBUG "tty_release_dev: bad idx when trying to " - "free (%s)\n", tty->name); - tty_unlock(); - return 0; - } - if (!devpts) { - if (tty != tty->driver->ttys[idx]) { - tty_unlock(); - printk(KERN_DEBUG "tty_release_dev: driver.table[%d] not tty " - "for (%s)\n", idx, tty->name); - return 0; - } - if (tty->termios != tty->driver->termios[idx]) { - tty_unlock(); - printk(KERN_DEBUG "tty_release_dev: driver.termios[%d] not termios " - "for (%s)\n", - idx, tty->name); - return 0; - } - } -#endif - -#ifdef TTY_DEBUG_HANGUP - printk(KERN_DEBUG "tty_release_dev of %s (tty count=%d)...", - tty_name(tty, buf), tty->count); -#endif - -#ifdef TTY_PARANOIA_CHECK - if (tty->driver->other && - !(tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)) { - if (o_tty != tty->driver->other->ttys[idx]) { - tty_unlock(); - printk(KERN_DEBUG "tty_release_dev: other->table[%d] " - "not o_tty for (%s)\n", - idx, tty->name); - return 0 ; - } - if (o_tty->termios != tty->driver->other->termios[idx]) { - tty_unlock(); - printk(KERN_DEBUG "tty_release_dev: other->termios[%d] " - "not o_termios for (%s)\n", - idx, tty->name); - return 0; - } - if (o_tty->link != tty) { - tty_unlock(); - printk(KERN_DEBUG "tty_release_dev: bad pty pointers\n"); - return 0; - } - } -#endif - if (tty->ops->close) - tty->ops->close(tty, filp); - - tty_unlock(); - /* - * Sanity check: if tty->count is going to zero, there shouldn't be - * any waiters on tty->read_wait or tty->write_wait. We test the - * wait queues and kick everyone out _before_ actually starting to - * close. This ensures that we won't block while releasing the tty - * structure. - * - * The test for the o_tty closing is necessary, since the master and - * slave sides may close in any order. If the slave side closes out - * first, its count will be one, since the master side holds an open. - * Thus this test wouldn't be triggered at the time the slave closes, - * so we do it now. - * - * Note that it's possible for the tty to be opened again while we're - * flushing out waiters. By recalculating the closing flags before - * each iteration we avoid any problems. - */ - while (1) { - /* Guard against races with tty->count changes elsewhere and - opens on /dev/tty */ - - mutex_lock(&tty_mutex); - tty_lock(); - tty_closing = tty->count <= 1; - o_tty_closing = o_tty && - (o_tty->count <= (pty_master ? 1 : 0)); - do_sleep = 0; - - if (tty_closing) { - if (waitqueue_active(&tty->read_wait)) { - wake_up_poll(&tty->read_wait, POLLIN); - do_sleep++; - } - if (waitqueue_active(&tty->write_wait)) { - wake_up_poll(&tty->write_wait, POLLOUT); - do_sleep++; - } - } - if (o_tty_closing) { - if (waitqueue_active(&o_tty->read_wait)) { - wake_up_poll(&o_tty->read_wait, POLLIN); - do_sleep++; - } - if (waitqueue_active(&o_tty->write_wait)) { - wake_up_poll(&o_tty->write_wait, POLLOUT); - do_sleep++; - } - } - if (!do_sleep) - break; - - printk(KERN_WARNING "tty_release_dev: %s: read/write wait queue " - "active!\n", tty_name(tty, buf)); - tty_unlock(); - mutex_unlock(&tty_mutex); - schedule(); - } - - /* - * The closing flags are now consistent with the open counts on - * both sides, and we've completed the last operation that could - * block, so it's safe to proceed with closing. - */ - if (pty_master) { - if (--o_tty->count < 0) { - printk(KERN_WARNING "tty_release_dev: bad pty slave count " - "(%d) for %s\n", - o_tty->count, tty_name(o_tty, buf)); - o_tty->count = 0; - } - } - if (--tty->count < 0) { - printk(KERN_WARNING "tty_release_dev: bad tty->count (%d) for %s\n", - tty->count, tty_name(tty, buf)); - tty->count = 0; - } - - /* - * We've decremented tty->count, so we need to remove this file - * descriptor off the tty->tty_files list; this serves two - * purposes: - * - check_tty_count sees the correct number of file descriptors - * associated with this tty. - * - do_tty_hangup no longer sees this file descriptor as - * something that needs to be handled for hangups. - */ - tty_del_file(filp); - - /* - * Perform some housekeeping before deciding whether to return. - * - * Set the TTY_CLOSING flag if this was the last open. In the - * case of a pty we may have to wait around for the other side - * to close, and TTY_CLOSING makes sure we can't be reopened. - */ - if (tty_closing) - set_bit(TTY_CLOSING, &tty->flags); - if (o_tty_closing) - set_bit(TTY_CLOSING, &o_tty->flags); - - /* - * If _either_ side is closing, make sure there aren't any - * processes that still think tty or o_tty is their controlling - * tty. - */ - if (tty_closing || o_tty_closing) { - read_lock(&tasklist_lock); - session_clear_tty(tty->session); - if (o_tty) - session_clear_tty(o_tty->session); - read_unlock(&tasklist_lock); - } - - mutex_unlock(&tty_mutex); - - /* check whether both sides are closing ... */ - if (!tty_closing || (o_tty && !o_tty_closing)) { - tty_unlock(); - return 0; - } - -#ifdef TTY_DEBUG_HANGUP - printk(KERN_DEBUG "freeing tty structure..."); -#endif - /* - * Ask the line discipline code to release its structures - */ - tty_ldisc_release(tty, o_tty); - /* - * The release_tty function takes care of the details of clearing - * the slots and preserving the termios structure. - */ - release_tty(tty, idx); - - /* Make this pty number available for reallocation */ - if (devpts) - devpts_kill_index(inode, idx); - tty_unlock(); - return 0; -} - -/** - * tty_open - open a tty device - * @inode: inode of device file - * @filp: file pointer to tty - * - * tty_open and tty_release keep up the tty count that contains the - * number of opens done on a tty. We cannot use the inode-count, as - * different inodes might point to the same tty. - * - * Open-counting is needed for pty masters, as well as for keeping - * track of serial lines: DTR is dropped when the last close happens. - * (This is not done solely through tty->count, now. - Ted 1/27/92) - * - * The termios state of a pty is reset on first open so that - * settings don't persist across reuse. - * - * Locking: tty_mutex protects tty, get_tty_driver and tty_init_dev work. - * tty->count should protect the rest. - * ->siglock protects ->signal/->sighand - */ - -static int tty_open(struct inode *inode, struct file *filp) -{ - struct tty_struct *tty = NULL; - int noctty, retval; - struct tty_driver *driver; - int index; - dev_t device = inode->i_rdev; - unsigned saved_flags = filp->f_flags; - - nonseekable_open(inode, filp); - -retry_open: - noctty = filp->f_flags & O_NOCTTY; - index = -1; - retval = 0; - - mutex_lock(&tty_mutex); - tty_lock(); - - if (device == MKDEV(TTYAUX_MAJOR, 0)) { - tty = get_current_tty(); - if (!tty) { - tty_unlock(); - mutex_unlock(&tty_mutex); - return -ENXIO; - } - driver = tty_driver_kref_get(tty->driver); - index = tty->index; - filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ - /* noctty = 1; */ - /* FIXME: Should we take a driver reference ? */ - tty_kref_put(tty); - goto got_driver; - } -#ifdef CONFIG_VT - if (device == MKDEV(TTY_MAJOR, 0)) { - extern struct tty_driver *console_driver; - driver = tty_driver_kref_get(console_driver); - index = fg_console; - noctty = 1; - goto got_driver; - } -#endif - if (device == MKDEV(TTYAUX_MAJOR, 1)) { - struct tty_driver *console_driver = console_device(&index); - if (console_driver) { - driver = tty_driver_kref_get(console_driver); - if (driver) { - /* Don't let /dev/console block */ - filp->f_flags |= O_NONBLOCK; - noctty = 1; - goto got_driver; - } - } - tty_unlock(); - mutex_unlock(&tty_mutex); - return -ENODEV; - } - - driver = get_tty_driver(device, &index); - if (!driver) { - tty_unlock(); - mutex_unlock(&tty_mutex); - return -ENODEV; - } -got_driver: - if (!tty) { - /* check whether we're reopening an existing tty */ - tty = tty_driver_lookup_tty(driver, inode, index); - - if (IS_ERR(tty)) { - tty_unlock(); - mutex_unlock(&tty_mutex); - return PTR_ERR(tty); - } - } - - if (tty) { - retval = tty_reopen(tty); - if (retval) - tty = ERR_PTR(retval); - } else - tty = tty_init_dev(driver, index, 0); - - mutex_unlock(&tty_mutex); - tty_driver_kref_put(driver); - if (IS_ERR(tty)) { - tty_unlock(); - return PTR_ERR(tty); - } - - retval = tty_add_file(tty, filp); - if (retval) { - tty_unlock(); - return retval; - } - - check_tty_count(tty, "tty_open"); - if (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->driver->subtype == PTY_TYPE_MASTER) - noctty = 1; -#ifdef TTY_DEBUG_HANGUP - printk(KERN_DEBUG "opening %s...", tty->name); -#endif - if (!retval) { - if (tty->ops->open) - retval = tty->ops->open(tty, filp); - else - retval = -ENODEV; - } - filp->f_flags = saved_flags; - - if (!retval && test_bit(TTY_EXCLUSIVE, &tty->flags) && - !capable(CAP_SYS_ADMIN)) - retval = -EBUSY; - - if (retval) { -#ifdef TTY_DEBUG_HANGUP - printk(KERN_DEBUG "error %d in opening %s...", retval, - tty->name); -#endif - tty_unlock(); /* need to call tty_release without BTM */ - tty_release(inode, filp); - if (retval != -ERESTARTSYS) - return retval; - - if (signal_pending(current)) - return retval; - - schedule(); - /* - * Need to reset f_op in case a hangup happened. - */ - tty_lock(); - if (filp->f_op == &hung_up_tty_fops) - filp->f_op = &tty_fops; - tty_unlock(); - goto retry_open; - } - tty_unlock(); - - - mutex_lock(&tty_mutex); - tty_lock(); - spin_lock_irq(¤t->sighand->siglock); - if (!noctty && - current->signal->leader && - !current->signal->tty && - tty->session == NULL) - __proc_set_tty(current, tty); - spin_unlock_irq(¤t->sighand->siglock); - tty_unlock(); - mutex_unlock(&tty_mutex); - return 0; -} - - - -/** - * tty_poll - check tty status - * @filp: file being polled - * @wait: poll wait structures to update - * - * Call the line discipline polling method to obtain the poll - * status of the device. - * - * Locking: locks called line discipline but ldisc poll method - * may be re-entered freely by other callers. - */ - -static unsigned int tty_poll(struct file *filp, poll_table *wait) -{ - struct tty_struct *tty = file_tty(filp); - struct tty_ldisc *ld; - int ret = 0; - - if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_poll")) - return 0; - - ld = tty_ldisc_ref_wait(tty); - if (ld->ops->poll) - ret = (ld->ops->poll)(tty, filp, wait); - tty_ldisc_deref(ld); - return ret; -} - -static int __tty_fasync(int fd, struct file *filp, int on) -{ - struct tty_struct *tty = file_tty(filp); - unsigned long flags; - int retval = 0; - - if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_fasync")) - goto out; - - retval = fasync_helper(fd, filp, on, &tty->fasync); - if (retval <= 0) - goto out; - - if (on) { - enum pid_type type; - struct pid *pid; - if (!waitqueue_active(&tty->read_wait)) - tty->minimum_to_wake = 1; - spin_lock_irqsave(&tty->ctrl_lock, flags); - if (tty->pgrp) { - pid = tty->pgrp; - type = PIDTYPE_PGID; - } else { - pid = task_pid(current); - type = PIDTYPE_PID; - } - get_pid(pid); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - retval = __f_setown(filp, pid, type, 0); - put_pid(pid); - if (retval) - goto out; - } else { - if (!tty->fasync && !waitqueue_active(&tty->read_wait)) - tty->minimum_to_wake = N_TTY_BUF_SIZE; - } - retval = 0; -out: - return retval; -} - -static int tty_fasync(int fd, struct file *filp, int on) -{ - int retval; - tty_lock(); - retval = __tty_fasync(fd, filp, on); - tty_unlock(); - return retval; -} - -/** - * tiocsti - fake input character - * @tty: tty to fake input into - * @p: pointer to character - * - * Fake input to a tty device. Does the necessary locking and - * input management. - * - * FIXME: does not honour flow control ?? - * - * Locking: - * Called functions take tty_ldisc_lock - * current->signal->tty check is safe without locks - * - * FIXME: may race normal receive processing - */ - -static int tiocsti(struct tty_struct *tty, char __user *p) -{ - char ch, mbz = 0; - struct tty_ldisc *ld; - - if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) - return -EPERM; - if (get_user(ch, p)) - return -EFAULT; - tty_audit_tiocsti(tty, ch); - ld = tty_ldisc_ref_wait(tty); - ld->ops->receive_buf(tty, &ch, &mbz, 1); - tty_ldisc_deref(ld); - return 0; -} - -/** - * tiocgwinsz - implement window query ioctl - * @tty; tty - * @arg: user buffer for result - * - * Copies the kernel idea of the window size into the user buffer. - * - * Locking: tty->termios_mutex is taken to ensure the winsize data - * is consistent. - */ - -static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) -{ - int err; - - mutex_lock(&tty->termios_mutex); - err = copy_to_user(arg, &tty->winsize, sizeof(*arg)); - mutex_unlock(&tty->termios_mutex); - - return err ? -EFAULT: 0; -} - -/** - * tty_do_resize - resize event - * @tty: tty being resized - * @rows: rows (character) - * @cols: cols (character) - * - * Update the termios variables and send the necessary signals to - * peform a terminal resize correctly - */ - -int tty_do_resize(struct tty_struct *tty, struct winsize *ws) -{ - struct pid *pgrp; - unsigned long flags; - - /* Lock the tty */ - mutex_lock(&tty->termios_mutex); - if (!memcmp(ws, &tty->winsize, sizeof(*ws))) - goto done; - /* Get the PID values and reference them so we can - avoid holding the tty ctrl lock while sending signals */ - spin_lock_irqsave(&tty->ctrl_lock, flags); - pgrp = get_pid(tty->pgrp); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - - if (pgrp) - kill_pgrp(pgrp, SIGWINCH, 1); - put_pid(pgrp); - - tty->winsize = *ws; -done: - mutex_unlock(&tty->termios_mutex); - return 0; -} - -/** - * tiocswinsz - implement window size set ioctl - * @tty; tty side of tty - * @arg: user buffer for result - * - * Copies the user idea of the window size to the kernel. Traditionally - * this is just advisory information but for the Linux console it - * actually has driver level meaning and triggers a VC resize. - * - * Locking: - * Driver dependant. The default do_resize method takes the - * tty termios mutex and ctrl_lock. The console takes its own lock - * then calls into the default method. - */ - -static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) -{ - struct winsize tmp_ws; - if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) - return -EFAULT; - - if (tty->ops->resize) - return tty->ops->resize(tty, &tmp_ws); - else - return tty_do_resize(tty, &tmp_ws); -} - -/** - * tioccons - allow admin to move logical console - * @file: the file to become console - * - * Allow the adminstrator to move the redirected console device - * - * Locking: uses redirect_lock to guard the redirect information - */ - -static int tioccons(struct file *file) -{ - if (!capable(CAP_SYS_ADMIN)) - return -EPERM; - if (file->f_op->write == redirected_tty_write) { - struct file *f; - spin_lock(&redirect_lock); - f = redirect; - redirect = NULL; - spin_unlock(&redirect_lock); - if (f) - fput(f); - return 0; - } - spin_lock(&redirect_lock); - if (redirect) { - spin_unlock(&redirect_lock); - return -EBUSY; - } - get_file(file); - redirect = file; - spin_unlock(&redirect_lock); - return 0; -} - -/** - * fionbio - non blocking ioctl - * @file: file to set blocking value - * @p: user parameter - * - * Historical tty interfaces had a blocking control ioctl before - * the generic functionality existed. This piece of history is preserved - * in the expected tty API of posix OS's. - * - * Locking: none, the open file handle ensures it won't go away. - */ - -static int fionbio(struct file *file, int __user *p) -{ - int nonblock; - - if (get_user(nonblock, p)) - return -EFAULT; - - spin_lock(&file->f_lock); - if (nonblock) - file->f_flags |= O_NONBLOCK; - else - file->f_flags &= ~O_NONBLOCK; - spin_unlock(&file->f_lock); - return 0; -} - -/** - * tiocsctty - set controlling tty - * @tty: tty structure - * @arg: user argument - * - * This ioctl is used to manage job control. It permits a session - * leader to set this tty as the controlling tty for the session. - * - * Locking: - * Takes tty_mutex() to protect tty instance - * Takes tasklist_lock internally to walk sessions - * Takes ->siglock() when updating signal->tty - */ - -static int tiocsctty(struct tty_struct *tty, int arg) -{ - int ret = 0; - if (current->signal->leader && (task_session(current) == tty->session)) - return ret; - - mutex_lock(&tty_mutex); - /* - * The process must be a session leader and - * not have a controlling tty already. - */ - if (!current->signal->leader || current->signal->tty) { - ret = -EPERM; - goto unlock; - } - - if (tty->session) { - /* - * This tty is already the controlling - * tty for another session group! - */ - if (arg == 1 && capable(CAP_SYS_ADMIN)) { - /* - * Steal it away - */ - read_lock(&tasklist_lock); - session_clear_tty(tty->session); - read_unlock(&tasklist_lock); - } else { - ret = -EPERM; - goto unlock; - } - } - proc_set_tty(current, tty); -unlock: - mutex_unlock(&tty_mutex); - return ret; -} - -/** - * tty_get_pgrp - return a ref counted pgrp pid - * @tty: tty to read - * - * Returns a refcounted instance of the pid struct for the process - * group controlling the tty. - */ - -struct pid *tty_get_pgrp(struct tty_struct *tty) -{ - unsigned long flags; - struct pid *pgrp; - - spin_lock_irqsave(&tty->ctrl_lock, flags); - pgrp = get_pid(tty->pgrp); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - - return pgrp; -} -EXPORT_SYMBOL_GPL(tty_get_pgrp); - -/** - * tiocgpgrp - get process group - * @tty: tty passed by user - * @real_tty: tty side of the tty pased by the user if a pty else the tty - * @p: returned pid - * - * Obtain the process group of the tty. If there is no process group - * return an error. - * - * Locking: none. Reference to current->signal->tty is safe. - */ - -static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) -{ - struct pid *pid; - int ret; - /* - * (tty == real_tty) is a cheap way of - * testing if the tty is NOT a master pty. - */ - if (tty == real_tty && current->signal->tty != real_tty) - return -ENOTTY; - pid = tty_get_pgrp(real_tty); - ret = put_user(pid_vnr(pid), p); - put_pid(pid); - return ret; -} - -/** - * tiocspgrp - attempt to set process group - * @tty: tty passed by user - * @real_tty: tty side device matching tty passed by user - * @p: pid pointer - * - * Set the process group of the tty to the session passed. Only - * permitted where the tty session is our session. - * - * Locking: RCU, ctrl lock - */ - -static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) -{ - struct pid *pgrp; - pid_t pgrp_nr; - int retval = tty_check_change(real_tty); - unsigned long flags; - - if (retval == -EIO) - return -ENOTTY; - if (retval) - return retval; - if (!current->signal->tty || - (current->signal->tty != real_tty) || - (real_tty->session != task_session(current))) - return -ENOTTY; - if (get_user(pgrp_nr, p)) - return -EFAULT; - if (pgrp_nr < 0) - return -EINVAL; - rcu_read_lock(); - pgrp = find_vpid(pgrp_nr); - retval = -ESRCH; - if (!pgrp) - goto out_unlock; - retval = -EPERM; - if (session_of_pgrp(pgrp) != task_session(current)) - goto out_unlock; - retval = 0; - spin_lock_irqsave(&tty->ctrl_lock, flags); - put_pid(real_tty->pgrp); - real_tty->pgrp = get_pid(pgrp); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); -out_unlock: - rcu_read_unlock(); - return retval; -} - -/** - * tiocgsid - get session id - * @tty: tty passed by user - * @real_tty: tty side of the tty pased by the user if a pty else the tty - * @p: pointer to returned session id - * - * Obtain the session id of the tty. If there is no session - * return an error. - * - * Locking: none. Reference to current->signal->tty is safe. - */ - -static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) -{ - /* - * (tty == real_tty) is a cheap way of - * testing if the tty is NOT a master pty. - */ - if (tty == real_tty && current->signal->tty != real_tty) - return -ENOTTY; - if (!real_tty->session) - return -ENOTTY; - return put_user(pid_vnr(real_tty->session), p); -} - -/** - * tiocsetd - set line discipline - * @tty: tty device - * @p: pointer to user data - * - * Set the line discipline according to user request. - * - * Locking: see tty_set_ldisc, this function is just a helper - */ - -static int tiocsetd(struct tty_struct *tty, int __user *p) -{ - int ldisc; - int ret; - - if (get_user(ldisc, p)) - return -EFAULT; - - ret = tty_set_ldisc(tty, ldisc); - - return ret; -} - -/** - * send_break - performed time break - * @tty: device to break on - * @duration: timeout in mS - * - * Perform a timed break on hardware that lacks its own driver level - * timed break functionality. - * - * Locking: - * atomic_write_lock serializes - * - */ - -static int send_break(struct tty_struct *tty, unsigned int duration) -{ - int retval; - - if (tty->ops->break_ctl == NULL) - return 0; - - if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK) - retval = tty->ops->break_ctl(tty, duration); - else { - /* Do the work ourselves */ - if (tty_write_lock(tty, 0) < 0) - return -EINTR; - retval = tty->ops->break_ctl(tty, -1); - if (retval) - goto out; - if (!signal_pending(current)) - msleep_interruptible(duration); - retval = tty->ops->break_ctl(tty, 0); -out: - tty_write_unlock(tty); - if (signal_pending(current)) - retval = -EINTR; - } - return retval; -} - -/** - * tty_tiocmget - get modem status - * @tty: tty device - * @file: user file pointer - * @p: pointer to result - * - * Obtain the modem status bits from the tty driver if the feature - * is supported. Return -EINVAL if it is not available. - * - * Locking: none (up to the driver) - */ - -static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p) -{ - int retval = -EINVAL; - - if (tty->ops->tiocmget) { - retval = tty->ops->tiocmget(tty, file); - - if (retval >= 0) - retval = put_user(retval, p); - } - return retval; -} - -/** - * tty_tiocmset - set modem status - * @tty: tty device - * @file: user file pointer - * @cmd: command - clear bits, set bits or set all - * @p: pointer to desired bits - * - * Set the modem status bits from the tty driver if the feature - * is supported. Return -EINVAL if it is not available. - * - * Locking: none (up to the driver) - */ - -static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int cmd, - unsigned __user *p) -{ - int retval; - unsigned int set, clear, val; - - if (tty->ops->tiocmset == NULL) - return -EINVAL; - - retval = get_user(val, p); - if (retval) - return retval; - set = clear = 0; - switch (cmd) { - case TIOCMBIS: - set = val; - break; - case TIOCMBIC: - clear = val; - break; - case TIOCMSET: - set = val; - clear = ~val; - break; - } - set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; - clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; - return tty->ops->tiocmset(tty, file, set, clear); -} - -static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) -{ - int retval = -EINVAL; - struct serial_icounter_struct icount; - memset(&icount, 0, sizeof(icount)); - if (tty->ops->get_icount) - retval = tty->ops->get_icount(tty, &icount); - if (retval != 0) - return retval; - if (copy_to_user(arg, &icount, sizeof(icount))) - return -EFAULT; - return 0; -} - -struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) -{ - if (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->driver->subtype == PTY_TYPE_MASTER) - tty = tty->link; - return tty; -} -EXPORT_SYMBOL(tty_pair_get_tty); - -struct tty_struct *tty_pair_get_pty(struct tty_struct *tty) -{ - if (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->driver->subtype == PTY_TYPE_MASTER) - return tty; - return tty->link; -} -EXPORT_SYMBOL(tty_pair_get_pty); - -/* - * Split this up, as gcc can choke on it otherwise.. - */ -long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) -{ - struct tty_struct *tty = file_tty(file); - struct tty_struct *real_tty; - void __user *p = (void __user *)arg; - int retval; - struct tty_ldisc *ld; - struct inode *inode = file->f_dentry->d_inode; - - if (tty_paranoia_check(tty, inode, "tty_ioctl")) - return -EINVAL; - - real_tty = tty_pair_get_tty(tty); - - /* - * Factor out some common prep work - */ - switch (cmd) { - case TIOCSETD: - case TIOCSBRK: - case TIOCCBRK: - case TCSBRK: - case TCSBRKP: - retval = tty_check_change(tty); - if (retval) - return retval; - if (cmd != TIOCCBRK) { - tty_wait_until_sent(tty, 0); - if (signal_pending(current)) - return -EINTR; - } - break; - } - - /* - * Now do the stuff. - */ - switch (cmd) { - case TIOCSTI: - return tiocsti(tty, p); - case TIOCGWINSZ: - return tiocgwinsz(real_tty, p); - case TIOCSWINSZ: - return tiocswinsz(real_tty, p); - case TIOCCONS: - return real_tty != tty ? -EINVAL : tioccons(file); - case FIONBIO: - return fionbio(file, p); - case TIOCEXCL: - set_bit(TTY_EXCLUSIVE, &tty->flags); - return 0; - case TIOCNXCL: - clear_bit(TTY_EXCLUSIVE, &tty->flags); - return 0; - case TIOCNOTTY: - if (current->signal->tty != tty) - return -ENOTTY; - no_tty(); - return 0; - case TIOCSCTTY: - return tiocsctty(tty, arg); - case TIOCGPGRP: - return tiocgpgrp(tty, real_tty, p); - case TIOCSPGRP: - return tiocspgrp(tty, real_tty, p); - case TIOCGSID: - return tiocgsid(tty, real_tty, p); - case TIOCGETD: - return put_user(tty->ldisc->ops->num, (int __user *)p); - case TIOCSETD: - return tiocsetd(tty, p); - /* - * Break handling - */ - case TIOCSBRK: /* Turn break on, unconditionally */ - if (tty->ops->break_ctl) - return tty->ops->break_ctl(tty, -1); - return 0; - case TIOCCBRK: /* Turn break off, unconditionally */ - if (tty->ops->break_ctl) - return tty->ops->break_ctl(tty, 0); - return 0; - case TCSBRK: /* SVID version: non-zero arg --> no break */ - /* non-zero arg means wait for all output data - * to be sent (performed above) but don't send break. - * This is used by the tcdrain() termios function. - */ - if (!arg) - return send_break(tty, 250); - return 0; - case TCSBRKP: /* support for POSIX tcsendbreak() */ - return send_break(tty, arg ? arg*100 : 250); - - case TIOCMGET: - return tty_tiocmget(tty, file, p); - case TIOCMSET: - case TIOCMBIC: - case TIOCMBIS: - return tty_tiocmset(tty, file, cmd, p); - case TIOCGICOUNT: - retval = tty_tiocgicount(tty, p); - /* For the moment allow fall through to the old method */ - if (retval != -EINVAL) - return retval; - break; - case TCFLSH: - switch (arg) { - case TCIFLUSH: - case TCIOFLUSH: - /* flush tty buffer and allow ldisc to process ioctl */ - tty_buffer_flush(tty); - break; - } - break; - } - if (tty->ops->ioctl) { - retval = (tty->ops->ioctl)(tty, file, cmd, arg); - if (retval != -ENOIOCTLCMD) - return retval; - } - ld = tty_ldisc_ref_wait(tty); - retval = -EINVAL; - if (ld->ops->ioctl) { - retval = ld->ops->ioctl(tty, file, cmd, arg); - if (retval == -ENOIOCTLCMD) - retval = -EINVAL; - } - tty_ldisc_deref(ld); - return retval; -} - -#ifdef CONFIG_COMPAT -static long tty_compat_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - struct inode *inode = file->f_dentry->d_inode; - struct tty_struct *tty = file_tty(file); - struct tty_ldisc *ld; - int retval = -ENOIOCTLCMD; - - if (tty_paranoia_check(tty, inode, "tty_ioctl")) - return -EINVAL; - - if (tty->ops->compat_ioctl) { - retval = (tty->ops->compat_ioctl)(tty, file, cmd, arg); - if (retval != -ENOIOCTLCMD) - return retval; - } - - ld = tty_ldisc_ref_wait(tty); - if (ld->ops->compat_ioctl) - retval = ld->ops->compat_ioctl(tty, file, cmd, arg); - tty_ldisc_deref(ld); - - return retval; -} -#endif - -/* - * This implements the "Secure Attention Key" --- the idea is to - * prevent trojan horses by killing all processes associated with this - * tty when the user hits the "Secure Attention Key". Required for - * super-paranoid applications --- see the Orange Book for more details. - * - * This code could be nicer; ideally it should send a HUP, wait a few - * seconds, then send a INT, and then a KILL signal. But you then - * have to coordinate with the init process, since all processes associated - * with the current tty must be dead before the new getty is allowed - * to spawn. - * - * Now, if it would be correct ;-/ The current code has a nasty hole - - * it doesn't catch files in flight. We may send the descriptor to ourselves - * via AF_UNIX socket, close it and later fetch from socket. FIXME. - * - * Nasty bug: do_SAK is being called in interrupt context. This can - * deadlock. We punt it up to process context. AKPM - 16Mar2001 - */ -void __do_SAK(struct tty_struct *tty) -{ -#ifdef TTY_SOFT_SAK - tty_hangup(tty); -#else - struct task_struct *g, *p; - struct pid *session; - int i; - struct file *filp; - struct fdtable *fdt; - - if (!tty) - return; - session = tty->session; - - tty_ldisc_flush(tty); - - tty_driver_flush_buffer(tty); - - read_lock(&tasklist_lock); - /* Kill the entire session */ - do_each_pid_task(session, PIDTYPE_SID, p) { - printk(KERN_NOTICE "SAK: killed process %d" - " (%s): task_session(p)==tty->session\n", - task_pid_nr(p), p->comm); - send_sig(SIGKILL, p, 1); - } while_each_pid_task(session, PIDTYPE_SID, p); - /* Now kill any processes that happen to have the - * tty open. - */ - do_each_thread(g, p) { - if (p->signal->tty == tty) { - printk(KERN_NOTICE "SAK: killed process %d" - " (%s): task_session(p)==tty->session\n", - task_pid_nr(p), p->comm); - send_sig(SIGKILL, p, 1); - continue; - } - task_lock(p); - if (p->files) { - /* - * We don't take a ref to the file, so we must - * hold ->file_lock instead. - */ - spin_lock(&p->files->file_lock); - fdt = files_fdtable(p->files); - for (i = 0; i < fdt->max_fds; i++) { - filp = fcheck_files(p->files, i); - if (!filp) - continue; - if (filp->f_op->read == tty_read && - file_tty(filp) == tty) { - printk(KERN_NOTICE "SAK: killed process %d" - " (%s): fd#%d opened to the tty\n", - task_pid_nr(p), p->comm, i); - force_sig(SIGKILL, p); - break; - } - } - spin_unlock(&p->files->file_lock); - } - task_unlock(p); - } while_each_thread(g, p); - read_unlock(&tasklist_lock); -#endif -} - -static void do_SAK_work(struct work_struct *work) -{ - struct tty_struct *tty = - container_of(work, struct tty_struct, SAK_work); - __do_SAK(tty); -} - -/* - * The tq handling here is a little racy - tty->SAK_work may already be queued. - * Fortunately we don't need to worry, because if ->SAK_work is already queued, - * the values which we write to it will be identical to the values which it - * already has. --akpm - */ -void do_SAK(struct tty_struct *tty) -{ - if (!tty) - return; - schedule_work(&tty->SAK_work); -} - -EXPORT_SYMBOL(do_SAK); - -static int dev_match_devt(struct device *dev, void *data) -{ - dev_t *devt = data; - return dev->devt == *devt; -} - -/* Must put_device() after it's unused! */ -static struct device *tty_get_device(struct tty_struct *tty) -{ - dev_t devt = tty_devnum(tty); - return class_find_device(tty_class, NULL, &devt, dev_match_devt); -} - - -/** - * initialize_tty_struct - * @tty: tty to initialize - * - * This subroutine initializes a tty structure that has been newly - * allocated. - * - * Locking: none - tty in question must not be exposed at this point - */ - -void initialize_tty_struct(struct tty_struct *tty, - struct tty_driver *driver, int idx) -{ - memset(tty, 0, sizeof(struct tty_struct)); - kref_init(&tty->kref); - tty->magic = TTY_MAGIC; - tty_ldisc_init(tty); - tty->session = NULL; - tty->pgrp = NULL; - tty->overrun_time = jiffies; - tty->buf.head = tty->buf.tail = NULL; - tty_buffer_init(tty); - mutex_init(&tty->termios_mutex); - mutex_init(&tty->ldisc_mutex); - init_waitqueue_head(&tty->write_wait); - init_waitqueue_head(&tty->read_wait); - INIT_WORK(&tty->hangup_work, do_tty_hangup); - mutex_init(&tty->atomic_read_lock); - mutex_init(&tty->atomic_write_lock); - mutex_init(&tty->output_lock); - mutex_init(&tty->echo_lock); - spin_lock_init(&tty->read_lock); - spin_lock_init(&tty->ctrl_lock); - INIT_LIST_HEAD(&tty->tty_files); - INIT_WORK(&tty->SAK_work, do_SAK_work); - - tty->driver = driver; - tty->ops = driver->ops; - tty->index = idx; - tty_line_name(driver, idx, tty->name); - tty->dev = tty_get_device(tty); -} - -/** - * tty_put_char - write one character to a tty - * @tty: tty - * @ch: character - * - * Write one byte to the tty using the provided put_char method - * if present. Returns the number of characters successfully output. - * - * Note: the specific put_char operation in the driver layer may go - * away soon. Don't call it directly, use this method - */ - -int tty_put_char(struct tty_struct *tty, unsigned char ch) -{ - if (tty->ops->put_char) - return tty->ops->put_char(tty, ch); - return tty->ops->write(tty, &ch, 1); -} -EXPORT_SYMBOL_GPL(tty_put_char); - -struct class *tty_class; - -/** - * tty_register_device - register a tty device - * @driver: the tty driver that describes the tty device - * @index: the index in the tty driver for this tty device - * @device: a struct device that is associated with this tty device. - * This field is optional, if there is no known struct device - * for this tty device it can be set to NULL safely. - * - * Returns a pointer to the struct device for this tty device - * (or ERR_PTR(-EFOO) on error). - * - * This call is required to be made to register an individual tty device - * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If - * that bit is not set, this function should not be called by a tty - * driver. - * - * Locking: ?? - */ - -struct device *tty_register_device(struct tty_driver *driver, unsigned index, - struct device *device) -{ - char name[64]; - dev_t dev = MKDEV(driver->major, driver->minor_start) + index; - - if (index >= driver->num) { - printk(KERN_ERR "Attempt to register invalid tty line number " - " (%d).\n", index); - return ERR_PTR(-EINVAL); - } - - if (driver->type == TTY_DRIVER_TYPE_PTY) - pty_line_name(driver, index, name); - else - tty_line_name(driver, index, name); - - return device_create(tty_class, device, dev, NULL, name); -} -EXPORT_SYMBOL(tty_register_device); - -/** - * tty_unregister_device - unregister a tty device - * @driver: the tty driver that describes the tty device - * @index: the index in the tty driver for this tty device - * - * If a tty device is registered with a call to tty_register_device() then - * this function must be called when the tty device is gone. - * - * Locking: ?? - */ - -void tty_unregister_device(struct tty_driver *driver, unsigned index) -{ - device_destroy(tty_class, - MKDEV(driver->major, driver->minor_start) + index); -} -EXPORT_SYMBOL(tty_unregister_device); - -struct tty_driver *alloc_tty_driver(int lines) -{ - struct tty_driver *driver; - - driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL); - if (driver) { - kref_init(&driver->kref); - driver->magic = TTY_DRIVER_MAGIC; - driver->num = lines; - /* later we'll move allocation of tables here */ - } - return driver; -} -EXPORT_SYMBOL(alloc_tty_driver); - -static void destruct_tty_driver(struct kref *kref) -{ - struct tty_driver *driver = container_of(kref, struct tty_driver, kref); - int i; - struct ktermios *tp; - void *p; - - if (driver->flags & TTY_DRIVER_INSTALLED) { - /* - * Free the termios and termios_locked structures because - * we don't want to get memory leaks when modular tty - * drivers are removed from the kernel. - */ - for (i = 0; i < driver->num; i++) { - tp = driver->termios[i]; - if (tp) { - driver->termios[i] = NULL; - kfree(tp); - } - if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) - tty_unregister_device(driver, i); - } - p = driver->ttys; - proc_tty_unregister_driver(driver); - driver->ttys = NULL; - driver->termios = NULL; - kfree(p); - cdev_del(&driver->cdev); - } - kfree(driver); -} - -void tty_driver_kref_put(struct tty_driver *driver) -{ - kref_put(&driver->kref, destruct_tty_driver); -} -EXPORT_SYMBOL(tty_driver_kref_put); - -void tty_set_operations(struct tty_driver *driver, - const struct tty_operations *op) -{ - driver->ops = op; -}; -EXPORT_SYMBOL(tty_set_operations); - -void put_tty_driver(struct tty_driver *d) -{ - tty_driver_kref_put(d); -} -EXPORT_SYMBOL(put_tty_driver); - -/* - * Called by a tty driver to register itself. - */ -int tty_register_driver(struct tty_driver *driver) -{ - int error; - int i; - dev_t dev; - void **p = NULL; - struct device *d; - - if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) { - p = kzalloc(driver->num * 2 * sizeof(void *), GFP_KERNEL); - if (!p) - return -ENOMEM; - } - - if (!driver->major) { - error = alloc_chrdev_region(&dev, driver->minor_start, - driver->num, driver->name); - if (!error) { - driver->major = MAJOR(dev); - driver->minor_start = MINOR(dev); - } - } else { - dev = MKDEV(driver->major, driver->minor_start); - error = register_chrdev_region(dev, driver->num, driver->name); - } - if (error < 0) { - kfree(p); - return error; - } - - if (p) { - driver->ttys = (struct tty_struct **)p; - driver->termios = (struct ktermios **)(p + driver->num); - } else { - driver->ttys = NULL; - driver->termios = NULL; - } - - cdev_init(&driver->cdev, &tty_fops); - driver->cdev.owner = driver->owner; - error = cdev_add(&driver->cdev, dev, driver->num); - if (error) { - unregister_chrdev_region(dev, driver->num); - driver->ttys = NULL; - driver->termios = NULL; - kfree(p); - return error; - } - - mutex_lock(&tty_mutex); - list_add(&driver->tty_drivers, &tty_drivers); - mutex_unlock(&tty_mutex); - - if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) { - for (i = 0; i < driver->num; i++) { - d = tty_register_device(driver, i, NULL); - if (IS_ERR(d)) { - error = PTR_ERR(d); - goto err; - } - } - } - proc_tty_register_driver(driver); - driver->flags |= TTY_DRIVER_INSTALLED; - return 0; - -err: - for (i--; i >= 0; i--) - tty_unregister_device(driver, i); - - mutex_lock(&tty_mutex); - list_del(&driver->tty_drivers); - mutex_unlock(&tty_mutex); - - unregister_chrdev_region(dev, driver->num); - driver->ttys = NULL; - driver->termios = NULL; - kfree(p); - return error; -} - -EXPORT_SYMBOL(tty_register_driver); - -/* - * Called by a tty driver to unregister itself. - */ -int tty_unregister_driver(struct tty_driver *driver) -{ -#if 0 - /* FIXME */ - if (driver->refcount) - return -EBUSY; -#endif - unregister_chrdev_region(MKDEV(driver->major, driver->minor_start), - driver->num); - mutex_lock(&tty_mutex); - list_del(&driver->tty_drivers); - mutex_unlock(&tty_mutex); - return 0; -} - -EXPORT_SYMBOL(tty_unregister_driver); - -dev_t tty_devnum(struct tty_struct *tty) -{ - return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index; -} -EXPORT_SYMBOL(tty_devnum); - -void proc_clear_tty(struct task_struct *p) -{ - unsigned long flags; - struct tty_struct *tty; - spin_lock_irqsave(&p->sighand->siglock, flags); - tty = p->signal->tty; - p->signal->tty = NULL; - spin_unlock_irqrestore(&p->sighand->siglock, flags); - tty_kref_put(tty); -} - -/* Called under the sighand lock */ - -static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty) -{ - if (tty) { - unsigned long flags; - /* We should not have a session or pgrp to put here but.... */ - spin_lock_irqsave(&tty->ctrl_lock, flags); - put_pid(tty->session); - put_pid(tty->pgrp); - tty->pgrp = get_pid(task_pgrp(tsk)); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - tty->session = get_pid(task_session(tsk)); - if (tsk->signal->tty) { - printk(KERN_DEBUG "tty not NULL!!\n"); - tty_kref_put(tsk->signal->tty); - } - } - put_pid(tsk->signal->tty_old_pgrp); - tsk->signal->tty = tty_kref_get(tty); - tsk->signal->tty_old_pgrp = NULL; -} - -static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty) -{ - spin_lock_irq(&tsk->sighand->siglock); - __proc_set_tty(tsk, tty); - spin_unlock_irq(&tsk->sighand->siglock); -} - -struct tty_struct *get_current_tty(void) -{ - struct tty_struct *tty; - unsigned long flags; - - spin_lock_irqsave(¤t->sighand->siglock, flags); - tty = tty_kref_get(current->signal->tty); - spin_unlock_irqrestore(¤t->sighand->siglock, flags); - return tty; -} -EXPORT_SYMBOL_GPL(get_current_tty); - -void tty_default_fops(struct file_operations *fops) -{ - *fops = tty_fops; -} - -/* - * Initialize the console device. This is called *early*, so - * we can't necessarily depend on lots of kernel help here. - * Just do some early initializations, and do the complex setup - * later. - */ -void __init console_init(void) -{ - initcall_t *call; - - /* Setup the default TTY line discipline. */ - tty_ldisc_begin(); - - /* - * set up the console device so that later boot sequences can - * inform about problems etc.. - */ - call = __con_initcall_start; - while (call < __con_initcall_end) { - (*call)(); - call++; - } -} - -static char *tty_devnode(struct device *dev, mode_t *mode) -{ - if (!mode) - return NULL; - if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) || - dev->devt == MKDEV(TTYAUX_MAJOR, 2)) - *mode = 0666; - return NULL; -} - -static int __init tty_class_init(void) -{ - tty_class = class_create(THIS_MODULE, "tty"); - if (IS_ERR(tty_class)) - return PTR_ERR(tty_class); - tty_class->devnode = tty_devnode; - return 0; -} - -postcore_initcall(tty_class_init); - -/* 3/2004 jmc: why do these devices exist? */ - -static struct cdev tty_cdev, console_cdev; - -/* - * Ok, now we can initialize the rest of the tty devices and can count - * on memory allocations, interrupts etc.. - */ -int __init tty_init(void) -{ - cdev_init(&tty_cdev, &tty_fops); - if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) || - register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0) - panic("Couldn't register /dev/tty driver\n"); - device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, - "tty"); - - cdev_init(&console_cdev, &console_fops); - if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) || - register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) - panic("Couldn't register /dev/console driver\n"); - device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL, - "console"); - -#ifdef CONFIG_VT - vty_init(&console_fops); -#endif - return 0; -} - diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c deleted file mode 100644 index 0c18899..0000000 --- a/drivers/char/tty_ioctl.c +++ /dev/null @@ -1,1179 +0,0 @@ -/* - * linux/drivers/char/tty_ioctl.c - * - * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds - * - * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines - * which can be dynamically activated and de-activated by the line - * discipline handling modules (like SLIP). - */ - -#include <linux/types.h> -#include <linux/termios.h> -#include <linux/errno.h> -#include <linux/sched.h> -#include <linux/kernel.h> -#include <linux/major.h> -#include <linux/tty.h> -#include <linux/fcntl.h> -#include <linux/string.h> -#include <linux/mm.h> -#include <linux/module.h> -#include <linux/bitops.h> -#include <linux/mutex.h> - -#include <asm/io.h> -#include <asm/uaccess.h> -#include <asm/system.h> - -#undef TTY_DEBUG_WAIT_UNTIL_SENT - -#undef DEBUG - -/* - * Internal flag options for termios setting behavior - */ -#define TERMIOS_FLUSH 1 -#define TERMIOS_WAIT 2 -#define TERMIOS_TERMIO 4 -#define TERMIOS_OLD 8 - - -/** - * tty_chars_in_buffer - characters pending - * @tty: terminal - * - * Return the number of bytes of data in the device private - * output queue. If no private method is supplied there is assumed - * to be no queue on the device. - */ - -int tty_chars_in_buffer(struct tty_struct *tty) -{ - if (tty->ops->chars_in_buffer) - return tty->ops->chars_in_buffer(tty); - else - return 0; -} -EXPORT_SYMBOL(tty_chars_in_buffer); - -/** - * tty_write_room - write queue space - * @tty: terminal - * - * Return the number of bytes that can be queued to this device - * at the present time. The result should be treated as a guarantee - * and the driver cannot offer a value it later shrinks by more than - * the number of bytes written. If no method is provided 2K is always - * returned and data may be lost as there will be no flow control. - */ - -int tty_write_room(struct tty_struct *tty) -{ - if (tty->ops->write_room) - return tty->ops->write_room(tty); - return 2048; -} -EXPORT_SYMBOL(tty_write_room); - -/** - * tty_driver_flush_buffer - discard internal buffer - * @tty: terminal - * - * Discard the internal output buffer for this device. If no method - * is provided then either the buffer cannot be hardware flushed or - * there is no buffer driver side. - */ -void tty_driver_flush_buffer(struct tty_struct *tty) -{ - if (tty->ops->flush_buffer) - tty->ops->flush_buffer(tty); -} -EXPORT_SYMBOL(tty_driver_flush_buffer); - -/** - * tty_throttle - flow control - * @tty: terminal - * - * Indicate that a tty should stop transmitting data down the stack. - * Takes the termios mutex to protect against parallel throttle/unthrottle - * and also to ensure the driver can consistently reference its own - * termios data at this point when implementing software flow control. - */ - -void tty_throttle(struct tty_struct *tty) -{ - mutex_lock(&tty->termios_mutex); - /* check TTY_THROTTLED first so it indicates our state */ - if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && - tty->ops->throttle) - tty->ops->throttle(tty); - mutex_unlock(&tty->termios_mutex); -} -EXPORT_SYMBOL(tty_throttle); - -/** - * tty_unthrottle - flow control - * @tty: terminal - * - * Indicate that a tty may continue transmitting data down the stack. - * Takes the termios mutex to protect against parallel throttle/unthrottle - * and also to ensure the driver can consistently reference its own - * termios data at this point when implementing software flow control. - * - * Drivers should however remember that the stack can issue a throttle, - * then change flow control method, then unthrottle. - */ - -void tty_unthrottle(struct tty_struct *tty) -{ - mutex_lock(&tty->termios_mutex); - if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && - tty->ops->unthrottle) - tty->ops->unthrottle(tty); - mutex_unlock(&tty->termios_mutex); -} -EXPORT_SYMBOL(tty_unthrottle); - -/** - * tty_wait_until_sent - wait for I/O to finish - * @tty: tty we are waiting for - * @timeout: how long we will wait - * - * Wait for characters pending in a tty driver to hit the wire, or - * for a timeout to occur (eg due to flow control) - * - * Locking: none - */ - -void tty_wait_until_sent(struct tty_struct *tty, long timeout) -{ -#ifdef TTY_DEBUG_WAIT_UNTIL_SENT - char buf[64]; - - printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf)); -#endif - if (!timeout) - timeout = MAX_SCHEDULE_TIMEOUT; - if (wait_event_interruptible_timeout(tty->write_wait, - !tty_chars_in_buffer(tty), timeout) >= 0) { - if (tty->ops->wait_until_sent) - tty->ops->wait_until_sent(tty, timeout); - } -} -EXPORT_SYMBOL(tty_wait_until_sent); - - -/* - * Termios Helper Methods - */ - -static void unset_locked_termios(struct ktermios *termios, - struct ktermios *old, - struct ktermios *locked) -{ - int i; - -#define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z))) - - if (!locked) { - printk(KERN_WARNING "Warning?!? termios_locked is NULL.\n"); - return; - } - - NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag); - NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag); - NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag); - NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag); - termios->c_line = locked->c_line ? old->c_line : termios->c_line; - for (i = 0; i < NCCS; i++) - termios->c_cc[i] = locked->c_cc[i] ? - old->c_cc[i] : termios->c_cc[i]; - /* FIXME: What should we do for i/ospeed */ -} - -/* - * Routine which returns the baud rate of the tty - * - * Note that the baud_table needs to be kept in sync with the - * include/asm/termbits.h file. - */ -static const speed_t baud_table[] = { - 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, - 9600, 19200, 38400, 57600, 115200, 230400, 460800, -#ifdef __sparc__ - 76800, 153600, 307200, 614400, 921600 -#else - 500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000, - 2500000, 3000000, 3500000, 4000000 -#endif -}; - -#ifndef __sparc__ -static const tcflag_t baud_bits[] = { - B0, B50, B75, B110, B134, B150, B200, B300, B600, - B1200, B1800, B2400, B4800, B9600, B19200, B38400, - B57600, B115200, B230400, B460800, B500000, B576000, - B921600, B1000000, B1152000, B1500000, B2000000, B2500000, - B3000000, B3500000, B4000000 -}; -#else -static const tcflag_t baud_bits[] = { - B0, B50, B75, B110, B134, B150, B200, B300, B600, - B1200, B1800, B2400, B4800, B9600, B19200, B38400, - B57600, B115200, B230400, B460800, B76800, B153600, - B307200, B614400, B921600 -}; -#endif - -static int n_baud_table = ARRAY_SIZE(baud_table); - -/** - * tty_termios_baud_rate - * @termios: termios structure - * - * Convert termios baud rate data into a speed. This should be called - * with the termios lock held if this termios is a terminal termios - * structure. May change the termios data. Device drivers can call this - * function but should use ->c_[io]speed directly as they are updated. - * - * Locking: none - */ - -speed_t tty_termios_baud_rate(struct ktermios *termios) -{ - unsigned int cbaud; - - cbaud = termios->c_cflag & CBAUD; - -#ifdef BOTHER - /* Magic token for arbitary speed via c_ispeed/c_ospeed */ - if (cbaud == BOTHER) - return termios->c_ospeed; -#endif - if (cbaud & CBAUDEX) { - cbaud &= ~CBAUDEX; - - if (cbaud < 1 || cbaud + 15 > n_baud_table) - termios->c_cflag &= ~CBAUDEX; - else - cbaud += 15; - } - return baud_table[cbaud]; -} -EXPORT_SYMBOL(tty_termios_baud_rate); - -/** - * tty_termios_input_baud_rate - * @termios: termios structure - * - * Convert termios baud rate data into a speed. This should be called - * with the termios lock held if this termios is a terminal termios - * structure. May change the termios data. Device drivers can call this - * function but should use ->c_[io]speed directly as they are updated. - * - * Locking: none - */ - -speed_t tty_termios_input_baud_rate(struct ktermios *termios) -{ -#ifdef IBSHIFT - unsigned int cbaud = (termios->c_cflag >> IBSHIFT) & CBAUD; - - if (cbaud == B0) - return tty_termios_baud_rate(termios); - - /* Magic token for arbitary speed via c_ispeed*/ - if (cbaud == BOTHER) - return termios->c_ispeed; - - if (cbaud & CBAUDEX) { - cbaud &= ~CBAUDEX; - - if (cbaud < 1 || cbaud + 15 > n_baud_table) - termios->c_cflag &= ~(CBAUDEX << IBSHIFT); - else - cbaud += 15; - } - return baud_table[cbaud]; -#else - return tty_termios_baud_rate(termios); -#endif -} -EXPORT_SYMBOL(tty_termios_input_baud_rate); - -/** - * tty_termios_encode_baud_rate - * @termios: ktermios structure holding user requested state - * @ispeed: input speed - * @ospeed: output speed - * - * Encode the speeds set into the passed termios structure. This is - * used as a library helper for drivers os that they can report back - * the actual speed selected when it differs from the speed requested - * - * For maximal back compatibility with legacy SYS5/POSIX *nix behaviour - * we need to carefully set the bits when the user does not get the - * desired speed. We allow small margins and preserve as much of possible - * of the input intent to keep compatibility. - * - * Locking: Caller should hold termios lock. This is already held - * when calling this function from the driver termios handler. - * - * The ifdefs deal with platforms whose owners have yet to update them - * and will all go away once this is done. - */ - -void tty_termios_encode_baud_rate(struct ktermios *termios, - speed_t ibaud, speed_t obaud) -{ - int i = 0; - int ifound = -1, ofound = -1; - int iclose = ibaud/50, oclose = obaud/50; - int ibinput = 0; - - if (obaud == 0) /* CD dropped */ - ibaud = 0; /* Clear ibaud to be sure */ - - termios->c_ispeed = ibaud; - termios->c_ospeed = obaud; - -#ifdef BOTHER - /* If the user asked for a precise weird speed give a precise weird - answer. If they asked for a Bfoo speed they many have problems - digesting non-exact replies so fuzz a bit */ - - if ((termios->c_cflag & CBAUD) == BOTHER) - oclose = 0; - if (((termios->c_cflag >> IBSHIFT) & CBAUD) == BOTHER) - iclose = 0; - if ((termios->c_cflag >> IBSHIFT) & CBAUD) - ibinput = 1; /* An input speed was specified */ -#endif - termios->c_cflag &= ~CBAUD; - - /* - * Our goal is to find a close match to the standard baud rate - * returned. Walk the baud rate table and if we get a very close - * match then report back the speed as a POSIX Bxxxx value by - * preference - */ - - do { - if (obaud - oclose <= baud_table[i] && - obaud + oclose >= baud_table[i]) { - termios->c_cflag |= baud_bits[i]; - ofound = i; - } - if (ibaud - iclose <= baud_table[i] && - ibaud + iclose >= baud_table[i]) { - /* For the case input == output don't set IBAUD bits - if the user didn't do so */ - if (ofound == i && !ibinput) - ifound = i; -#ifdef IBSHIFT - else { - ifound = i; - termios->c_cflag |= (baud_bits[i] << IBSHIFT); - } -#endif - } - } while (++i < n_baud_table); - - /* - * If we found no match then use BOTHER if provided or warn - * the user their platform maintainer needs to wake up if not. - */ -#ifdef BOTHER - if (ofound == -1) - termios->c_cflag |= BOTHER; - /* Set exact input bits only if the input and output differ or the - user already did */ - if (ifound == -1 && (ibaud != obaud || ibinput)) - termios->c_cflag |= (BOTHER << IBSHIFT); -#else - if (ifound == -1 || ofound == -1) { - printk_once(KERN_WARNING "tty: Unable to return correct " - "speed data as your architecture needs updating.\n"); - } -#endif -} -EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate); - -/** - * tty_encode_baud_rate - set baud rate of the tty - * @ibaud: input baud rate - * @obad: output baud rate - * - * Update the current termios data for the tty with the new speed - * settings. The caller must hold the termios_mutex for the tty in - * question. - */ - -void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud) -{ - tty_termios_encode_baud_rate(tty->termios, ibaud, obaud); -} -EXPORT_SYMBOL_GPL(tty_encode_baud_rate); - -/** - * tty_get_baud_rate - get tty bit rates - * @tty: tty to query - * - * Returns the baud rate as an integer for this terminal. The - * termios lock must be held by the caller and the terminal bit - * flags may be updated. - * - * Locking: none - */ - -speed_t tty_get_baud_rate(struct tty_struct *tty) -{ - speed_t baud = tty_termios_baud_rate(tty->termios); - - if (baud == 38400 && tty->alt_speed) { - if (!tty->warned) { - printk(KERN_WARNING "Use of setserial/setrocket to " - "set SPD_* flags is deprecated\n"); - tty->warned = 1; - } - baud = tty->alt_speed; - } - - return baud; -} -EXPORT_SYMBOL(tty_get_baud_rate); - -/** - * tty_termios_copy_hw - copy hardware settings - * @new: New termios - * @old: Old termios - * - * Propogate the hardware specific terminal setting bits from - * the old termios structure to the new one. This is used in cases - * where the hardware does not support reconfiguration or as a helper - * in some cases where only minimal reconfiguration is supported - */ - -void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old) -{ - /* The bits a dumb device handles in software. Smart devices need - to always provide a set_termios method */ - new->c_cflag &= HUPCL | CREAD | CLOCAL; - new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL); - new->c_ispeed = old->c_ispeed; - new->c_ospeed = old->c_ospeed; -} -EXPORT_SYMBOL(tty_termios_copy_hw); - -/** - * tty_termios_hw_change - check for setting change - * @a: termios - * @b: termios to compare - * - * Check if any of the bits that affect a dumb device have changed - * between the two termios structures, or a speed change is needed. - */ - -int tty_termios_hw_change(struct ktermios *a, struct ktermios *b) -{ - if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) - return 1; - if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) - return 1; - return 0; -} -EXPORT_SYMBOL(tty_termios_hw_change); - -/** - * change_termios - update termios values - * @tty: tty to update - * @new_termios: desired new value - * - * Perform updates to the termios values set on this terminal. There - * is a bit of layering violation here with n_tty in terms of the - * internal knowledge of this function. - * - * Locking: termios_mutex - */ - -static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) -{ - struct ktermios old_termios; - struct tty_ldisc *ld; - unsigned long flags; - - /* - * Perform the actual termios internal changes under lock. - */ - - - /* FIXME: we need to decide on some locking/ordering semantics - for the set_termios notification eventually */ - mutex_lock(&tty->termios_mutex); - old_termios = *tty->termios; - *tty->termios = *new_termios; - unset_locked_termios(tty->termios, &old_termios, tty->termios_locked); - - /* See if packet mode change of state. */ - if (tty->link && tty->link->packet) { - int extproc = (old_termios.c_lflag & EXTPROC) | - (tty->termios->c_lflag & EXTPROC); - int old_flow = ((old_termios.c_iflag & IXON) && - (old_termios.c_cc[VSTOP] == '\023') && - (old_termios.c_cc[VSTART] == '\021')); - int new_flow = (I_IXON(tty) && - STOP_CHAR(tty) == '\023' && - START_CHAR(tty) == '\021'); - if ((old_flow != new_flow) || extproc) { - spin_lock_irqsave(&tty->ctrl_lock, flags); - if (old_flow != new_flow) { - tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP); - if (new_flow) - tty->ctrl_status |= TIOCPKT_DOSTOP; - else - tty->ctrl_status |= TIOCPKT_NOSTOP; - } - if (extproc) - tty->ctrl_status |= TIOCPKT_IOCTL; - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - wake_up_interruptible(&tty->link->read_wait); - } - } - - if (tty->ops->set_termios) - (*tty->ops->set_termios)(tty, &old_termios); - else - tty_termios_copy_hw(tty->termios, &old_termios); - - ld = tty_ldisc_ref(tty); - if (ld != NULL) { - if (ld->ops->set_termios) - (ld->ops->set_termios)(tty, &old_termios); - tty_ldisc_deref(ld); - } - mutex_unlock(&tty->termios_mutex); -} - -/** - * set_termios - set termios values for a tty - * @tty: terminal device - * @arg: user data - * @opt: option information - * - * Helper function to prepare termios data and run necessary other - * functions before using change_termios to do the actual changes. - * - * Locking: - * Called functions take ldisc and termios_mutex locks - */ - -static int set_termios(struct tty_struct *tty, void __user *arg, int opt) -{ - struct ktermios tmp_termios; - struct tty_ldisc *ld; - int retval = tty_check_change(tty); - - if (retval) - return retval; - - mutex_lock(&tty->termios_mutex); - memcpy(&tmp_termios, tty->termios, sizeof(struct ktermios)); - mutex_unlock(&tty->termios_mutex); - - if (opt & TERMIOS_TERMIO) { - if (user_termio_to_kernel_termios(&tmp_termios, - (struct termio __user *)arg)) - return -EFAULT; -#ifdef TCGETS2 - } else if (opt & TERMIOS_OLD) { - if (user_termios_to_kernel_termios_1(&tmp_termios, - (struct termios __user *)arg)) - return -EFAULT; - } else { - if (user_termios_to_kernel_termios(&tmp_termios, - (struct termios2 __user *)arg)) - return -EFAULT; - } -#else - } else if (user_termios_to_kernel_termios(&tmp_termios, - (struct termios __user *)arg)) - return -EFAULT; -#endif - - /* If old style Bfoo values are used then load c_ispeed/c_ospeed - * with the real speed so its unconditionally usable */ - tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios); - tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios); - - ld = tty_ldisc_ref(tty); - - if (ld != NULL) { - if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) - ld->ops->flush_buffer(tty); - tty_ldisc_deref(ld); - } - - if (opt & TERMIOS_WAIT) { - tty_wait_until_sent(tty, 0); - if (signal_pending(current)) - return -EINTR; - } - - change_termios(tty, &tmp_termios); - - /* FIXME: Arguably if tmp_termios == tty->termios AND the - actual requested termios was not tmp_termios then we may - want to return an error as no user requested change has - succeeded */ - return 0; -} - -static void copy_termios(struct tty_struct *tty, struct ktermios *kterm) -{ - mutex_lock(&tty->termios_mutex); - memcpy(kterm, tty->termios, sizeof(struct ktermios)); - mutex_unlock(&tty->termios_mutex); -} - -static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm) -{ - mutex_lock(&tty->termios_mutex); - memcpy(kterm, tty->termios_locked, sizeof(struct ktermios)); - mutex_unlock(&tty->termios_mutex); -} - -static int get_termio(struct tty_struct *tty, struct termio __user *termio) -{ - struct ktermios kterm; - copy_termios(tty, &kterm); - if (kernel_termios_to_user_termio(termio, &kterm)) - return -EFAULT; - return 0; -} - - -#ifdef TCGETX - -/** - * set_termiox - set termiox fields if possible - * @tty: terminal - * @arg: termiox structure from user - * @opt: option flags for ioctl type - * - * Implement the device calling points for the SYS5 termiox ioctl - * interface in Linux - */ - -static int set_termiox(struct tty_struct *tty, void __user *arg, int opt) -{ - struct termiox tnew; - struct tty_ldisc *ld; - - if (tty->termiox == NULL) - return -EINVAL; - if (copy_from_user(&tnew, arg, sizeof(struct termiox))) - return -EFAULT; - - ld = tty_ldisc_ref(tty); - if (ld != NULL) { - if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) - ld->ops->flush_buffer(tty); - tty_ldisc_deref(ld); - } - if (opt & TERMIOS_WAIT) { - tty_wait_until_sent(tty, 0); - if (signal_pending(current)) - return -EINTR; - } - - mutex_lock(&tty->termios_mutex); - if (tty->ops->set_termiox) - tty->ops->set_termiox(tty, &tnew); - mutex_unlock(&tty->termios_mutex); - return 0; -} - -#endif - - -#ifdef TIOCGETP -/* - * These are deprecated, but there is limited support.. - * - * The "sg_flags" translation is a joke.. - */ -static int get_sgflags(struct tty_struct *tty) -{ - int flags = 0; - - if (!(tty->termios->c_lflag & ICANON)) { - if (tty->termios->c_lflag & ISIG) - flags |= 0x02; /* cbreak */ - else - flags |= 0x20; /* raw */ - } - if (tty->termios->c_lflag & ECHO) - flags |= 0x08; /* echo */ - if (tty->termios->c_oflag & OPOST) - if (tty->termios->c_oflag & ONLCR) - flags |= 0x10; /* crmod */ - return flags; -} - -static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) -{ - struct sgttyb tmp; - - mutex_lock(&tty->termios_mutex); - tmp.sg_ispeed = tty->termios->c_ispeed; - tmp.sg_ospeed = tty->termios->c_ospeed; - tmp.sg_erase = tty->termios->c_cc[VERASE]; - tmp.sg_kill = tty->termios->c_cc[VKILL]; - tmp.sg_flags = get_sgflags(tty); - mutex_unlock(&tty->termios_mutex); - - return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0; -} - -static void set_sgflags(struct ktermios *termios, int flags) -{ - termios->c_iflag = ICRNL | IXON; - termios->c_oflag = 0; - termios->c_lflag = ISIG | ICANON; - if (flags & 0x02) { /* cbreak */ - termios->c_iflag = 0; - termios->c_lflag &= ~ICANON; - } - if (flags & 0x08) { /* echo */ - termios->c_lflag |= ECHO | ECHOE | ECHOK | - ECHOCTL | ECHOKE | IEXTEN; - } - if (flags & 0x10) { /* crmod */ - termios->c_oflag |= OPOST | ONLCR; - } - if (flags & 0x20) { /* raw */ - termios->c_iflag = 0; - termios->c_lflag &= ~(ISIG | ICANON); - } - if (!(termios->c_lflag & ICANON)) { - termios->c_cc[VMIN] = 1; - termios->c_cc[VTIME] = 0; - } -} - -/** - * set_sgttyb - set legacy terminal values - * @tty: tty structure - * @sgttyb: pointer to old style terminal structure - * - * Updates a terminal from the legacy BSD style terminal information - * structure. - * - * Locking: termios_mutex - */ - -static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) -{ - int retval; - struct sgttyb tmp; - struct ktermios termios; - - retval = tty_check_change(tty); - if (retval) - return retval; - - if (copy_from_user(&tmp, sgttyb, sizeof(tmp))) - return -EFAULT; - - mutex_lock(&tty->termios_mutex); - termios = *tty->termios; - termios.c_cc[VERASE] = tmp.sg_erase; - termios.c_cc[VKILL] = tmp.sg_kill; - set_sgflags(&termios, tmp.sg_flags); - /* Try and encode into Bfoo format */ -#ifdef BOTHER - tty_termios_encode_baud_rate(&termios, termios.c_ispeed, - termios.c_ospeed); -#endif - mutex_unlock(&tty->termios_mutex); - change_termios(tty, &termios); - return 0; -} -#endif - -#ifdef TIOCGETC -static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars) -{ - struct tchars tmp; - - mutex_lock(&tty->termios_mutex); - tmp.t_intrc = tty->termios->c_cc[VINTR]; - tmp.t_quitc = tty->termios->c_cc[VQUIT]; - tmp.t_startc = tty->termios->c_cc[VSTART]; - tmp.t_stopc = tty->termios->c_cc[VSTOP]; - tmp.t_eofc = tty->termios->c_cc[VEOF]; - tmp.t_brkc = tty->termios->c_cc[VEOL2]; /* what is brkc anyway? */ - mutex_unlock(&tty->termios_mutex); - return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; -} - -static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars) -{ - struct tchars tmp; - - if (copy_from_user(&tmp, tchars, sizeof(tmp))) - return -EFAULT; - mutex_lock(&tty->termios_mutex); - tty->termios->c_cc[VINTR] = tmp.t_intrc; - tty->termios->c_cc[VQUIT] = tmp.t_quitc; - tty->termios->c_cc[VSTART] = tmp.t_startc; - tty->termios->c_cc[VSTOP] = tmp.t_stopc; - tty->termios->c_cc[VEOF] = tmp.t_eofc; - tty->termios->c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */ - mutex_unlock(&tty->termios_mutex); - return 0; -} -#endif - -#ifdef TIOCGLTC -static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) -{ - struct ltchars tmp; - - mutex_lock(&tty->termios_mutex); - tmp.t_suspc = tty->termios->c_cc[VSUSP]; - /* what is dsuspc anyway? */ - tmp.t_dsuspc = tty->termios->c_cc[VSUSP]; - tmp.t_rprntc = tty->termios->c_cc[VREPRINT]; - /* what is flushc anyway? */ - tmp.t_flushc = tty->termios->c_cc[VEOL2]; - tmp.t_werasc = tty->termios->c_cc[VWERASE]; - tmp.t_lnextc = tty->termios->c_cc[VLNEXT]; - mutex_unlock(&tty->termios_mutex); - return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; -} - -static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) -{ - struct ltchars tmp; - - if (copy_from_user(&tmp, ltchars, sizeof(tmp))) - return -EFAULT; - - mutex_lock(&tty->termios_mutex); - tty->termios->c_cc[VSUSP] = tmp.t_suspc; - /* what is dsuspc anyway? */ - tty->termios->c_cc[VEOL2] = tmp.t_dsuspc; - tty->termios->c_cc[VREPRINT] = tmp.t_rprntc; - /* what is flushc anyway? */ - tty->termios->c_cc[VEOL2] = tmp.t_flushc; - tty->termios->c_cc[VWERASE] = tmp.t_werasc; - tty->termios->c_cc[VLNEXT] = tmp.t_lnextc; - mutex_unlock(&tty->termios_mutex); - return 0; -} -#endif - -/** - * send_prio_char - send priority character - * - * Send a high priority character to the tty even if stopped - * - * Locking: none for xchar method, write ordering for write method. - */ - -static int send_prio_char(struct tty_struct *tty, char ch) -{ - int was_stopped = tty->stopped; - - if (tty->ops->send_xchar) { - tty->ops->send_xchar(tty, ch); - return 0; - } - - if (tty_write_lock(tty, 0) < 0) - return -ERESTARTSYS; - - if (was_stopped) - start_tty(tty); - tty->ops->write(tty, &ch, 1); - if (was_stopped) - stop_tty(tty); - tty_write_unlock(tty); - return 0; -} - -/** - * tty_change_softcar - carrier change ioctl helper - * @tty: tty to update - * @arg: enable/disable CLOCAL - * - * Perform a change to the CLOCAL state and call into the driver - * layer to make it visible. All done with the termios mutex - */ - -static int tty_change_softcar(struct tty_struct *tty, int arg) -{ - int ret = 0; - int bit = arg ? CLOCAL : 0; - struct ktermios old; - - mutex_lock(&tty->termios_mutex); - old = *tty->termios; - tty->termios->c_cflag &= ~CLOCAL; - tty->termios->c_cflag |= bit; - if (tty->ops->set_termios) - tty->ops->set_termios(tty, &old); - if ((tty->termios->c_cflag & CLOCAL) != bit) - ret = -EINVAL; - mutex_unlock(&tty->termios_mutex); - return ret; -} - -/** - * tty_mode_ioctl - mode related ioctls - * @tty: tty for the ioctl - * @file: file pointer for the tty - * @cmd: command - * @arg: ioctl argument - * - * Perform non line discipline specific mode control ioctls. This - * is designed to be called by line disciplines to ensure they provide - * consistent mode setting. - */ - -int tty_mode_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - struct tty_struct *real_tty; - void __user *p = (void __user *)arg; - int ret = 0; - struct ktermios kterm; - - if (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->driver->subtype == PTY_TYPE_MASTER) - real_tty = tty->link; - else - real_tty = tty; - - switch (cmd) { -#ifdef TIOCGETP - case TIOCGETP: - return get_sgttyb(real_tty, (struct sgttyb __user *) arg); - case TIOCSETP: - case TIOCSETN: - return set_sgttyb(real_tty, (struct sgttyb __user *) arg); -#endif -#ifdef TIOCGETC - case TIOCGETC: - return get_tchars(real_tty, p); - case TIOCSETC: - return set_tchars(real_tty, p); -#endif -#ifdef TIOCGLTC - case TIOCGLTC: - return get_ltchars(real_tty, p); - case TIOCSLTC: - return set_ltchars(real_tty, p); -#endif - case TCSETSF: - return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_OLD); - case TCSETSW: - return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_OLD); - case TCSETS: - return set_termios(real_tty, p, TERMIOS_OLD); -#ifndef TCGETS2 - case TCGETS: - copy_termios(real_tty, &kterm); - if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) - ret = -EFAULT; - return ret; -#else - case TCGETS: - copy_termios(real_tty, &kterm); - if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) - ret = -EFAULT; - return ret; - case TCGETS2: - copy_termios(real_tty, &kterm); - if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm)) - ret = -EFAULT; - return ret; - case TCSETSF2: - return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT); - case TCSETSW2: - return set_termios(real_tty, p, TERMIOS_WAIT); - case TCSETS2: - return set_termios(real_tty, p, 0); -#endif - case TCGETA: - return get_termio(real_tty, p); - case TCSETAF: - return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO); - case TCSETAW: - return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO); - case TCSETA: - return set_termios(real_tty, p, TERMIOS_TERMIO); -#ifndef TCGETS2 - case TIOCGLCKTRMIOS: - copy_termios_locked(real_tty, &kterm); - if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) - ret = -EFAULT; - return ret; - case TIOCSLCKTRMIOS: - if (!capable(CAP_SYS_ADMIN)) - return -EPERM; - copy_termios_locked(real_tty, &kterm); - if (user_termios_to_kernel_termios(&kterm, - (struct termios __user *) arg)) - return -EFAULT; - mutex_lock(&real_tty->termios_mutex); - memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios)); - mutex_unlock(&real_tty->termios_mutex); - return 0; -#else - case TIOCGLCKTRMIOS: - copy_termios_locked(real_tty, &kterm); - if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) - ret = -EFAULT; - return ret; - case TIOCSLCKTRMIOS: - if (!capable(CAP_SYS_ADMIN)) - return -EPERM; - copy_termios_locked(real_tty, &kterm); - if (user_termios_to_kernel_termios_1(&kterm, - (struct termios __user *) arg)) - return -EFAULT; - mutex_lock(&real_tty->termios_mutex); - memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios)); - mutex_unlock(&real_tty->termios_mutex); - return ret; -#endif -#ifdef TCGETX - case TCGETX: { - struct termiox ktermx; - if (real_tty->termiox == NULL) - return -EINVAL; - mutex_lock(&real_tty->termios_mutex); - memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox)); - mutex_unlock(&real_tty->termios_mutex); - if (copy_to_user(p, &ktermx, sizeof(struct termiox))) - ret = -EFAULT; - return ret; - } - case TCSETX: - return set_termiox(real_tty, p, 0); - case TCSETXW: - return set_termiox(real_tty, p, TERMIOS_WAIT); - case TCSETXF: - return set_termiox(real_tty, p, TERMIOS_FLUSH); -#endif - case TIOCGSOFTCAR: - copy_termios(real_tty, &kterm); - ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0, - (int __user *)arg); - return ret; - case TIOCSSOFTCAR: - if (get_user(arg, (unsigned int __user *) arg)) - return -EFAULT; - return tty_change_softcar(real_tty, arg); - default: - return -ENOIOCTLCMD; - } -} -EXPORT_SYMBOL_GPL(tty_mode_ioctl); - -int tty_perform_flush(struct tty_struct *tty, unsigned long arg) -{ - struct tty_ldisc *ld; - int retval = tty_check_change(tty); - if (retval) - return retval; - - ld = tty_ldisc_ref_wait(tty); - switch (arg) { - case TCIFLUSH: - if (ld && ld->ops->flush_buffer) - ld->ops->flush_buffer(tty); - break; - case TCIOFLUSH: - if (ld && ld->ops->flush_buffer) - ld->ops->flush_buffer(tty); - /* fall through */ - case TCOFLUSH: - tty_driver_flush_buffer(tty); - break; - default: - tty_ldisc_deref(ld); - return -EINVAL; - } - tty_ldisc_deref(ld); - return 0; -} -EXPORT_SYMBOL_GPL(tty_perform_flush); - -int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - unsigned long flags; - int retval; - - switch (cmd) { - case TCXONC: - retval = tty_check_change(tty); - if (retval) - return retval; - switch (arg) { - case TCOOFF: - if (!tty->flow_stopped) { - tty->flow_stopped = 1; - stop_tty(tty); - } - break; - case TCOON: - if (tty->flow_stopped) { - tty->flow_stopped = 0; - start_tty(tty); - } - break; - case TCIOFF: - if (STOP_CHAR(tty) != __DISABLED_CHAR) - return send_prio_char(tty, STOP_CHAR(tty)); - break; - case TCION: - if (START_CHAR(tty) != __DISABLED_CHAR) - return send_prio_char(tty, START_CHAR(tty)); - break; - default: - return -EINVAL; - } - return 0; - case TCFLSH: - return tty_perform_flush(tty, arg); - case TIOCPKT: - { - int pktmode; - - if (tty->driver->type != TTY_DRIVER_TYPE_PTY || - tty->driver->subtype != PTY_TYPE_MASTER) - return -ENOTTY; - if (get_user(pktmode, (int __user *) arg)) - return -EFAULT; - spin_lock_irqsave(&tty->ctrl_lock, flags); - if (pktmode) { - if (!tty->packet) { - tty->packet = 1; - tty->link->ctrl_status = 0; - } - } else - tty->packet = 0; - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - return 0; - } - default: - /* Try the mode commands */ - return tty_mode_ioctl(tty, file, cmd, arg); - } -} -EXPORT_SYMBOL(n_tty_ioctl_helper); diff --git a/drivers/char/tty_ldisc.c b/drivers/char/tty_ldisc.c deleted file mode 100644 index 412f977..0000000 --- a/drivers/char/tty_ldisc.c +++ /dev/null @@ -1,915 +0,0 @@ -#include <linux/types.h> -#include <linux/major.h> -#include <linux/errno.h> -#include <linux/signal.h> -#include <linux/fcntl.h> -#include <linux/sched.h> -#include <linux/interrupt.h> -#include <linux/tty.h> -#include <linux/tty_driver.h> -#include <linux/tty_flip.h> -#include <linux/devpts_fs.h> -#include <linux/file.h> -#include <linux/console.h> -#include <linux/timer.h> -#include <linux/ctype.h> -#include <linux/kd.h> -#include <linux/mm.h> -#include <linux/string.h> -#include <linux/slab.h> -#include <linux/poll.h> -#include <linux/proc_fs.h> -#include <linux/init.h> -#include <linux/module.h> -#include <linux/device.h> -#include <linux/wait.h> -#include <linux/bitops.h> -#include <linux/delay.h> -#include <linux/seq_file.h> - -#include <linux/uaccess.h> -#include <asm/system.h> - -#include <linux/kbd_kern.h> -#include <linux/vt_kern.h> -#include <linux/selection.h> - -#include <linux/smp_lock.h> /* For the moment */ - -#include <linux/kmod.h> -#include <linux/nsproxy.h> - -/* - * This guards the refcounted line discipline lists. The lock - * must be taken with irqs off because there are hangup path - * callers who will do ldisc lookups and cannot sleep. - */ - -static DEFINE_SPINLOCK(tty_ldisc_lock); -static DECLARE_WAIT_QUEUE_HEAD(tty_ldisc_wait); -/* Line disc dispatch table */ -static struct tty_ldisc_ops *tty_ldiscs[NR_LDISCS]; - -static inline struct tty_ldisc *get_ldisc(struct tty_ldisc *ld) -{ - if (ld) - atomic_inc(&ld->users); - return ld; -} - -static void put_ldisc(struct tty_ldisc *ld) -{ - unsigned long flags; - - if (WARN_ON_ONCE(!ld)) - return; - - /* - * If this is the last user, free the ldisc, and - * release the ldisc ops. - * - * We really want an "atomic_dec_and_lock_irqsave()", - * but we don't have it, so this does it by hand. - */ - local_irq_save(flags); - if (atomic_dec_and_lock(&ld->users, &tty_ldisc_lock)) { - struct tty_ldisc_ops *ldo = ld->ops; - - ldo->refcount--; - module_put(ldo->owner); - spin_unlock_irqrestore(&tty_ldisc_lock, flags); - - kfree(ld); - return; - } - local_irq_restore(flags); -} - -/** - * tty_register_ldisc - install a line discipline - * @disc: ldisc number - * @new_ldisc: pointer to the ldisc object - * - * Installs a new line discipline into the kernel. The discipline - * is set up as unreferenced and then made available to the kernel - * from this point onwards. - * - * Locking: - * takes tty_ldisc_lock to guard against ldisc races - */ - -int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc) -{ - unsigned long flags; - int ret = 0; - - if (disc < N_TTY || disc >= NR_LDISCS) - return -EINVAL; - - spin_lock_irqsave(&tty_ldisc_lock, flags); - tty_ldiscs[disc] = new_ldisc; - new_ldisc->num = disc; - new_ldisc->refcount = 0; - spin_unlock_irqrestore(&tty_ldisc_lock, flags); - - return ret; -} -EXPORT_SYMBOL(tty_register_ldisc); - -/** - * tty_unregister_ldisc - unload a line discipline - * @disc: ldisc number - * @new_ldisc: pointer to the ldisc object - * - * Remove a line discipline from the kernel providing it is not - * currently in use. - * - * Locking: - * takes tty_ldisc_lock to guard against ldisc races - */ - -int tty_unregister_ldisc(int disc) -{ - unsigned long flags; - int ret = 0; - - if (disc < N_TTY || disc >= NR_LDISCS) - return -EINVAL; - - spin_lock_irqsave(&tty_ldisc_lock, flags); - if (tty_ldiscs[disc]->refcount) - ret = -EBUSY; - else - tty_ldiscs[disc] = NULL; - spin_unlock_irqrestore(&tty_ldisc_lock, flags); - - return ret; -} -EXPORT_SYMBOL(tty_unregister_ldisc); - -static struct tty_ldisc_ops *get_ldops(int disc) -{ - unsigned long flags; - struct tty_ldisc_ops *ldops, *ret; - - spin_lock_irqsave(&tty_ldisc_lock, flags); - ret = ERR_PTR(-EINVAL); - ldops = tty_ldiscs[disc]; - if (ldops) { - ret = ERR_PTR(-EAGAIN); - if (try_module_get(ldops->owner)) { - ldops->refcount++; - ret = ldops; - } - } - spin_unlock_irqrestore(&tty_ldisc_lock, flags); - return ret; -} - -static void put_ldops(struct tty_ldisc_ops *ldops) -{ - unsigned long flags; - - spin_lock_irqsave(&tty_ldisc_lock, flags); - ldops->refcount--; - module_put(ldops->owner); - spin_unlock_irqrestore(&tty_ldisc_lock, flags); -} - -/** - * tty_ldisc_get - take a reference to an ldisc - * @disc: ldisc number - * - * Takes a reference to a line discipline. Deals with refcounts and - * module locking counts. Returns NULL if the discipline is not available. - * Returns a pointer to the discipline and bumps the ref count if it is - * available - * - * Locking: - * takes tty_ldisc_lock to guard against ldisc races - */ - -static struct tty_ldisc *tty_ldisc_get(int disc) -{ - struct tty_ldisc *ld; - struct tty_ldisc_ops *ldops; - - if (disc < N_TTY || disc >= NR_LDISCS) - return ERR_PTR(-EINVAL); - - /* - * Get the ldisc ops - we may need to request them to be loaded - * dynamically and try again. - */ - ldops = get_ldops(disc); - if (IS_ERR(ldops)) { - request_module("tty-ldisc-%d", disc); - ldops = get_ldops(disc); - if (IS_ERR(ldops)) - return ERR_CAST(ldops); - } - - ld = kmalloc(sizeof(struct tty_ldisc), GFP_KERNEL); - if (ld == NULL) { - put_ldops(ldops); - return ERR_PTR(-ENOMEM); - } - - ld->ops = ldops; - atomic_set(&ld->users, 1); - return ld; -} - -static void *tty_ldiscs_seq_start(struct seq_file *m, loff_t *pos) -{ - return (*pos < NR_LDISCS) ? pos : NULL; -} - -static void *tty_ldiscs_seq_next(struct seq_file *m, void *v, loff_t *pos) -{ - (*pos)++; - return (*pos < NR_LDISCS) ? pos : NULL; -} - -static void tty_ldiscs_seq_stop(struct seq_file *m, void *v) -{ -} - -static int tty_ldiscs_seq_show(struct seq_file *m, void *v) -{ - int i = *(loff_t *)v; - struct tty_ldisc_ops *ldops; - - ldops = get_ldops(i); - if (IS_ERR(ldops)) - return 0; - seq_printf(m, "%-10s %2d\n", ldops->name ? ldops->name : "???", i); - put_ldops(ldops); - return 0; -} - -static const struct seq_operations tty_ldiscs_seq_ops = { - .start = tty_ldiscs_seq_start, - .next = tty_ldiscs_seq_next, - .stop = tty_ldiscs_seq_stop, - .show = tty_ldiscs_seq_show, -}; - -static int proc_tty_ldiscs_open(struct inode *inode, struct file *file) -{ - return seq_open(file, &tty_ldiscs_seq_ops); -} - -const struct file_operations tty_ldiscs_proc_fops = { - .owner = THIS_MODULE, - .open = proc_tty_ldiscs_open, - .read = seq_read, - .llseek = seq_lseek, - .release = seq_release, -}; - -/** - * tty_ldisc_assign - set ldisc on a tty - * @tty: tty to assign - * @ld: line discipline - * - * Install an instance of a line discipline into a tty structure. The - * ldisc must have a reference count above zero to ensure it remains. - * The tty instance refcount starts at zero. - * - * Locking: - * Caller must hold references - */ - -static void tty_ldisc_assign(struct tty_struct *tty, struct tty_ldisc *ld) -{ - tty->ldisc = ld; -} - -/** - * tty_ldisc_try - internal helper - * @tty: the tty - * - * Make a single attempt to grab and bump the refcount on - * the tty ldisc. Return 0 on failure or 1 on success. This is - * used to implement both the waiting and non waiting versions - * of tty_ldisc_ref - * - * Locking: takes tty_ldisc_lock - */ - -static struct tty_ldisc *tty_ldisc_try(struct tty_struct *tty) -{ - unsigned long flags; - struct tty_ldisc *ld; - - spin_lock_irqsave(&tty_ldisc_lock, flags); - ld = NULL; - if (test_bit(TTY_LDISC, &tty->flags)) - ld = get_ldisc(tty->ldisc); - spin_unlock_irqrestore(&tty_ldisc_lock, flags); - return ld; -} - -/** - * tty_ldisc_ref_wait - wait for the tty ldisc - * @tty: tty device - * - * Dereference the line discipline for the terminal and take a - * reference to it. If the line discipline is in flux then - * wait patiently until it changes. - * - * Note: Must not be called from an IRQ/timer context. The caller - * must also be careful not to hold other locks that will deadlock - * against a discipline change, such as an existing ldisc reference - * (which we check for) - * - * Locking: call functions take tty_ldisc_lock - */ - -struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *tty) -{ - struct tty_ldisc *ld; - - /* wait_event is a macro */ - wait_event(tty_ldisc_wait, (ld = tty_ldisc_try(tty)) != NULL); - return ld; -} -EXPORT_SYMBOL_GPL(tty_ldisc_ref_wait); - -/** - * tty_ldisc_ref - get the tty ldisc - * @tty: tty device - * - * Dereference the line discipline for the terminal and take a - * reference to it. If the line discipline is in flux then - * return NULL. Can be called from IRQ and timer functions. - * - * Locking: called functions take tty_ldisc_lock - */ - -struct tty_ldisc *tty_ldisc_ref(struct tty_struct *tty) -{ - return tty_ldisc_try(tty); -} -EXPORT_SYMBOL_GPL(tty_ldisc_ref); - -/** - * tty_ldisc_deref - free a tty ldisc reference - * @ld: reference to free up - * - * Undoes the effect of tty_ldisc_ref or tty_ldisc_ref_wait. May - * be called in IRQ context. - * - * Locking: takes tty_ldisc_lock - */ - -void tty_ldisc_deref(struct tty_ldisc *ld) -{ - put_ldisc(ld); -} -EXPORT_SYMBOL_GPL(tty_ldisc_deref); - -static inline void tty_ldisc_put(struct tty_ldisc *ld) -{ - put_ldisc(ld); -} - -/** - * tty_ldisc_enable - allow ldisc use - * @tty: terminal to activate ldisc on - * - * Set the TTY_LDISC flag when the line discipline can be called - * again. Do necessary wakeups for existing sleepers. Clear the LDISC - * changing flag to indicate any ldisc change is now over. - * - * Note: nobody should set the TTY_LDISC bit except via this function. - * Clearing directly is allowed. - */ - -void tty_ldisc_enable(struct tty_struct *tty) -{ - set_bit(TTY_LDISC, &tty->flags); - clear_bit(TTY_LDISC_CHANGING, &tty->flags); - wake_up(&tty_ldisc_wait); -} - -/** - * tty_ldisc_flush - flush line discipline queue - * @tty: tty - * - * Flush the line discipline queue (if any) for this tty. If there - * is no line discipline active this is a no-op. - */ - -void tty_ldisc_flush(struct tty_struct *tty) -{ - struct tty_ldisc *ld = tty_ldisc_ref(tty); - if (ld) { - if (ld->ops->flush_buffer) - ld->ops->flush_buffer(tty); - tty_ldisc_deref(ld); - } - tty_buffer_flush(tty); -} -EXPORT_SYMBOL_GPL(tty_ldisc_flush); - -/** - * tty_set_termios_ldisc - set ldisc field - * @tty: tty structure - * @num: line discipline number - * - * This is probably overkill for real world processors but - * they are not on hot paths so a little discipline won't do - * any harm. - * - * Locking: takes termios_mutex - */ - -static void tty_set_termios_ldisc(struct tty_struct *tty, int num) -{ - mutex_lock(&tty->termios_mutex); - tty->termios->c_line = num; - mutex_unlock(&tty->termios_mutex); -} - -/** - * tty_ldisc_open - open a line discipline - * @tty: tty we are opening the ldisc on - * @ld: discipline to open - * - * A helper opening method. Also a convenient debugging and check - * point. - * - * Locking: always called with BTM already held. - */ - -static int tty_ldisc_open(struct tty_struct *tty, struct tty_ldisc *ld) -{ - WARN_ON(test_and_set_bit(TTY_LDISC_OPEN, &tty->flags)); - if (ld->ops->open) { - int ret; - /* BTM here locks versus a hangup event */ - WARN_ON(!tty_locked()); - ret = ld->ops->open(tty); - return ret; - } - return 0; -} - -/** - * tty_ldisc_close - close a line discipline - * @tty: tty we are opening the ldisc on - * @ld: discipline to close - * - * A helper close method. Also a convenient debugging and check - * point. - */ - -static void tty_ldisc_close(struct tty_struct *tty, struct tty_ldisc *ld) -{ - WARN_ON(!test_bit(TTY_LDISC_OPEN, &tty->flags)); - clear_bit(TTY_LDISC_OPEN, &tty->flags); - if (ld->ops->close) - ld->ops->close(tty); -} - -/** - * tty_ldisc_restore - helper for tty ldisc change - * @tty: tty to recover - * @old: previous ldisc - * - * Restore the previous line discipline or N_TTY when a line discipline - * change fails due to an open error - */ - -static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old) -{ - char buf[64]; - struct tty_ldisc *new_ldisc; - int r; - - /* There is an outstanding reference here so this is safe */ - old = tty_ldisc_get(old->ops->num); - WARN_ON(IS_ERR(old)); - tty_ldisc_assign(tty, old); - tty_set_termios_ldisc(tty, old->ops->num); - if (tty_ldisc_open(tty, old) < 0) { - tty_ldisc_put(old); - /* This driver is always present */ - new_ldisc = tty_ldisc_get(N_TTY); - if (IS_ERR(new_ldisc)) - panic("n_tty: get"); - tty_ldisc_assign(tty, new_ldisc); - tty_set_termios_ldisc(tty, N_TTY); - r = tty_ldisc_open(tty, new_ldisc); - if (r < 0) - panic("Couldn't open N_TTY ldisc for " - "%s --- error %d.", - tty_name(tty, buf), r); - } -} - -/** - * tty_ldisc_halt - shut down the line discipline - * @tty: tty device - * - * Shut down the line discipline and work queue for this tty device. - * The TTY_LDISC flag being cleared ensures no further references can - * be obtained while the delayed work queue halt ensures that no more - * data is fed to the ldisc. - * - * You need to do a 'flush_scheduled_work()' (outside the ldisc_mutex) - * in order to make sure any currently executing ldisc work is also - * flushed. - */ - -static int tty_ldisc_halt(struct tty_struct *tty) -{ - clear_bit(TTY_LDISC, &tty->flags); - return cancel_delayed_work_sync(&tty->buf.work); -} - -/** - * tty_set_ldisc - set line discipline - * @tty: the terminal to set - * @ldisc: the line discipline - * - * Set the discipline of a tty line. Must be called from a process - * context. The ldisc change logic has to protect itself against any - * overlapping ldisc change (including on the other end of pty pairs), - * the close of one side of a tty/pty pair, and eventually hangup. - * - * Locking: takes tty_ldisc_lock, termios_mutex - */ - -int tty_set_ldisc(struct tty_struct *tty, int ldisc) -{ - int retval; - struct tty_ldisc *o_ldisc, *new_ldisc; - int work, o_work = 0; - struct tty_struct *o_tty; - - new_ldisc = tty_ldisc_get(ldisc); - if (IS_ERR(new_ldisc)) - return PTR_ERR(new_ldisc); - - tty_lock(); - /* - * We need to look at the tty locking here for pty/tty pairs - * when both sides try to change in parallel. - */ - - o_tty = tty->link; /* o_tty is the pty side or NULL */ - - - /* - * Check the no-op case - */ - - if (tty->ldisc->ops->num == ldisc) { - tty_unlock(); - tty_ldisc_put(new_ldisc); - return 0; - } - - tty_unlock(); - /* - * Problem: What do we do if this blocks ? - * We could deadlock here - */ - - tty_wait_until_sent(tty, 0); - - tty_lock(); - mutex_lock(&tty->ldisc_mutex); - - /* - * We could be midstream of another ldisc change which has - * dropped the lock during processing. If so we need to wait. - */ - - while (test_bit(TTY_LDISC_CHANGING, &tty->flags)) { - mutex_unlock(&tty->ldisc_mutex); - tty_unlock(); - wait_event(tty_ldisc_wait, - test_bit(TTY_LDISC_CHANGING, &tty->flags) == 0); - tty_lock(); - mutex_lock(&tty->ldisc_mutex); - } - - set_bit(TTY_LDISC_CHANGING, &tty->flags); - - /* - * No more input please, we are switching. The new ldisc - * will update this value in the ldisc open function - */ - - tty->receive_room = 0; - - o_ldisc = tty->ldisc; - - tty_unlock(); - /* - * Make sure we don't change while someone holds a - * reference to the line discipline. The TTY_LDISC bit - * prevents anyone taking a reference once it is clear. - * We need the lock to avoid racing reference takers. - * - * We must clear the TTY_LDISC bit here to avoid a livelock - * with a userspace app continually trying to use the tty in - * parallel to the change and re-referencing the tty. - */ - - work = tty_ldisc_halt(tty); - if (o_tty) - o_work = tty_ldisc_halt(o_tty); - - /* - * Wait for ->hangup_work and ->buf.work handlers to terminate. - * We must drop the mutex here in case a hangup is also in process. - */ - - mutex_unlock(&tty->ldisc_mutex); - - flush_scheduled_work(); - - tty_lock(); - mutex_lock(&tty->ldisc_mutex); - if (test_bit(TTY_HUPPED, &tty->flags)) { - /* We were raced by the hangup method. It will have stomped - the ldisc data and closed the ldisc down */ - clear_bit(TTY_LDISC_CHANGING, &tty->flags); - mutex_unlock(&tty->ldisc_mutex); - tty_ldisc_put(new_ldisc); - tty_unlock(); - return -EIO; - } - - /* Shutdown the current discipline. */ - tty_ldisc_close(tty, o_ldisc); - - /* Now set up the new line discipline. */ - tty_ldisc_assign(tty, new_ldisc); - tty_set_termios_ldisc(tty, ldisc); - - retval = tty_ldisc_open(tty, new_ldisc); - if (retval < 0) { - /* Back to the old one or N_TTY if we can't */ - tty_ldisc_put(new_ldisc); - tty_ldisc_restore(tty, o_ldisc); - } - - /* At this point we hold a reference to the new ldisc and a - a reference to the old ldisc. If we ended up flipping back - to the existing ldisc we have two references to it */ - - if (tty->ldisc->ops->num != o_ldisc->ops->num && tty->ops->set_ldisc) - tty->ops->set_ldisc(tty); - - tty_ldisc_put(o_ldisc); - - /* - * Allow ldisc referencing to occur again - */ - - tty_ldisc_enable(tty); - if (o_tty) - tty_ldisc_enable(o_tty); - - /* Restart the work queue in case no characters kick it off. Safe if - already running */ - if (work) - schedule_delayed_work(&tty->buf.work, 1); - if (o_work) - schedule_delayed_work(&o_tty->buf.work, 1); - mutex_unlock(&tty->ldisc_mutex); - tty_unlock(); - return retval; -} - -/** - * tty_reset_termios - reset terminal state - * @tty: tty to reset - * - * Restore a terminal to the driver default state. - */ - -static void tty_reset_termios(struct tty_struct *tty) -{ - mutex_lock(&tty->termios_mutex); - *tty->termios = tty->driver->init_termios; - tty->termios->c_ispeed = tty_termios_input_baud_rate(tty->termios); - tty->termios->c_ospeed = tty_termios_baud_rate(tty->termios); - mutex_unlock(&tty->termios_mutex); -} - - -/** - * tty_ldisc_reinit - reinitialise the tty ldisc - * @tty: tty to reinit - * @ldisc: line discipline to reinitialize - * - * Switch the tty to a line discipline and leave the ldisc - * state closed - */ - -static void tty_ldisc_reinit(struct tty_struct *tty, int ldisc) -{ - struct tty_ldisc *ld; - - tty_ldisc_close(tty, tty->ldisc); - tty_ldisc_put(tty->ldisc); - tty->ldisc = NULL; - /* - * Switch the line discipline back - */ - ld = tty_ldisc_get(ldisc); - BUG_ON(IS_ERR(ld)); - tty_ldisc_assign(tty, ld); - tty_set_termios_ldisc(tty, ldisc); -} - -/** - * tty_ldisc_hangup - hangup ldisc reset - * @tty: tty being hung up - * - * Some tty devices reset their termios when they receive a hangup - * event. In that situation we must also switch back to N_TTY properly - * before we reset the termios data. - * - * Locking: We can take the ldisc mutex as the rest of the code is - * careful to allow for this. - * - * In the pty pair case this occurs in the close() path of the - * tty itself so we must be careful about locking rules. - */ - -void tty_ldisc_hangup(struct tty_struct *tty) -{ - struct tty_ldisc *ld; - int reset = tty->driver->flags & TTY_DRIVER_RESET_TERMIOS; - int err = 0; - - /* - * FIXME! What are the locking issues here? This may me overdoing - * things... This question is especially important now that we've - * removed the irqlock. - */ - ld = tty_ldisc_ref(tty); - if (ld != NULL) { - /* We may have no line discipline at this point */ - if (ld->ops->flush_buffer) - ld->ops->flush_buffer(tty); - tty_driver_flush_buffer(tty); - if ((test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) && - ld->ops->write_wakeup) - ld->ops->write_wakeup(tty); - if (ld->ops->hangup) - ld->ops->hangup(tty); - tty_ldisc_deref(ld); - } - /* - * FIXME: Once we trust the LDISC code better we can wait here for - * ldisc completion and fix the driver call race - */ - wake_up_interruptible_poll(&tty->write_wait, POLLOUT); - wake_up_interruptible_poll(&tty->read_wait, POLLIN); - /* - * Shutdown the current line discipline, and reset it to - * N_TTY if need be. - * - * Avoid racing set_ldisc or tty_ldisc_release - */ - mutex_lock(&tty->ldisc_mutex); - - /* - * this is like tty_ldisc_halt, but we need to give up - * the BTM before calling cancel_delayed_work_sync, - * which may need to wait for another function taking the BTM - */ - clear_bit(TTY_LDISC, &tty->flags); - tty_unlock(); - cancel_delayed_work_sync(&tty->buf.work); - mutex_unlock(&tty->ldisc_mutex); - - tty_lock(); - mutex_lock(&tty->ldisc_mutex); - - /* At this point we have a closed ldisc and we want to - reopen it. We could defer this to the next open but - it means auditing a lot of other paths so this is - a FIXME */ - if (tty->ldisc) { /* Not yet closed */ - if (reset == 0) { - tty_ldisc_reinit(tty, tty->termios->c_line); - err = tty_ldisc_open(tty, tty->ldisc); - } - /* If the re-open fails or we reset then go to N_TTY. The - N_TTY open cannot fail */ - if (reset || err) { - tty_ldisc_reinit(tty, N_TTY); - WARN_ON(tty_ldisc_open(tty, tty->ldisc)); - } - tty_ldisc_enable(tty); - } - mutex_unlock(&tty->ldisc_mutex); - if (reset) - tty_reset_termios(tty); -} - -/** - * tty_ldisc_setup - open line discipline - * @tty: tty being shut down - * @o_tty: pair tty for pty/tty pairs - * - * Called during the initial open of a tty/pty pair in order to set up the - * line disciplines and bind them to the tty. This has no locking issues - * as the device isn't yet active. - */ - -int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty) -{ - struct tty_ldisc *ld = tty->ldisc; - int retval; - - retval = tty_ldisc_open(tty, ld); - if (retval) - return retval; - - if (o_tty) { - retval = tty_ldisc_open(o_tty, o_tty->ldisc); - if (retval) { - tty_ldisc_close(tty, ld); - return retval; - } - tty_ldisc_enable(o_tty); - } - tty_ldisc_enable(tty); - return 0; -} -/** - * tty_ldisc_release - release line discipline - * @tty: tty being shut down - * @o_tty: pair tty for pty/tty pairs - * - * Called during the final close of a tty/pty pair in order to shut down - * the line discpline layer. On exit the ldisc assigned is N_TTY and the - * ldisc has not been opened. - */ - -void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty) -{ - /* - * Prevent flush_to_ldisc() from rescheduling the work for later. Then - * kill any delayed work. As this is the final close it does not - * race with the set_ldisc code path. - */ - - tty_unlock(); - tty_ldisc_halt(tty); - flush_scheduled_work(); - tty_lock(); - - mutex_lock(&tty->ldisc_mutex); - /* - * Now kill off the ldisc - */ - tty_ldisc_close(tty, tty->ldisc); - tty_ldisc_put(tty->ldisc); - /* Force an oops if we mess this up */ - tty->ldisc = NULL; - - /* Ensure the next open requests the N_TTY ldisc */ - tty_set_termios_ldisc(tty, N_TTY); - mutex_unlock(&tty->ldisc_mutex); - - /* This will need doing differently if we need to lock */ - if (o_tty) - tty_ldisc_release(o_tty, NULL); - - /* And the memory resources remaining (buffers, termios) will be - disposed of when the kref hits zero */ -} - -/** - * tty_ldisc_init - ldisc setup for new tty - * @tty: tty being allocated - * - * Set up the line discipline objects for a newly allocated tty. Note that - * the tty structure is not completely set up when this call is made. - */ - -void tty_ldisc_init(struct tty_struct *tty) -{ - struct tty_ldisc *ld = tty_ldisc_get(N_TTY); - if (IS_ERR(ld)) - panic("n_tty: init_tty"); - tty_ldisc_assign(tty, ld); -} - -void tty_ldisc_begin(void) -{ - /* Setup the default TTY line discipline. */ - (void) tty_register_ldisc(N_TTY, &tty_ldisc_N_TTY); -} diff --git a/drivers/char/tty_mutex.c b/drivers/char/tty_mutex.c deleted file mode 100644 index 1336975..0000000 --- a/drivers/char/tty_mutex.c +++ /dev/null @@ -1,47 +0,0 @@ -/* - * drivers/char/tty_lock.c - */ -#include <linux/tty.h> -#include <linux/module.h> -#include <linux/kallsyms.h> -#include <linux/semaphore.h> -#include <linux/sched.h> - -/* - * The 'big tty mutex' - * - * This mutex is taken and released by tty_lock() and tty_unlock(), - * replacing the older big kernel lock. - * It can no longer be taken recursively, and does not get - * released implicitly while sleeping. - * - * Don't use in new code. - */ -static DEFINE_MUTEX(big_tty_mutex); -struct task_struct *__big_tty_mutex_owner; -EXPORT_SYMBOL_GPL(__big_tty_mutex_owner); - -/* - * Getting the big tty mutex. - */ -void __lockfunc tty_lock(void) -{ - struct task_struct *task = current; - - WARN_ON(__big_tty_mutex_owner == task); - - mutex_lock(&big_tty_mutex); - __big_tty_mutex_owner = task; -} -EXPORT_SYMBOL(tty_lock); - -void __lockfunc tty_unlock(void) -{ - struct task_struct *task = current; - - WARN_ON(__big_tty_mutex_owner != task); - __big_tty_mutex_owner = NULL; - - mutex_unlock(&big_tty_mutex); -} -EXPORT_SYMBOL(tty_unlock); diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c deleted file mode 100644 index 33d37d2..0000000 --- a/drivers/char/tty_port.c +++ /dev/null @@ -1,446 +0,0 @@ -/* - * Tty port functions - */ - -#include <linux/types.h> -#include <linux/errno.h> -#include <linux/tty.h> -#include <linux/tty_driver.h> -#include <linux/tty_flip.h> -#include <linux/serial.h> -#include <linux/timer.h> -#include <linux/string.h> -#include <linux/slab.h> -#include <linux/sched.h> -#include <linux/init.h> -#include <linux/wait.h> -#include <linux/bitops.h> -#include <linux/delay.h> -#include <linux/module.h> - -void tty_port_init(struct tty_port *port) -{ - memset(port, 0, sizeof(*port)); - init_waitqueue_head(&port->open_wait); - init_waitqueue_head(&port->close_wait); - init_waitqueue_head(&port->delta_msr_wait); - mutex_init(&port->mutex); - mutex_init(&port->buf_mutex); - spin_lock_init(&port->lock); - port->close_delay = (50 * HZ) / 100; - port->closing_wait = (3000 * HZ) / 100; - kref_init(&port->kref); -} -EXPORT_SYMBOL(tty_port_init); - -int tty_port_alloc_xmit_buf(struct tty_port *port) -{ - /* We may sleep in get_zeroed_page() */ - mutex_lock(&port->buf_mutex); - if (port->xmit_buf == NULL) - port->xmit_buf = (unsigned char *)get_zeroed_page(GFP_KERNEL); - mutex_unlock(&port->buf_mutex); - if (port->xmit_buf == NULL) - return -ENOMEM; - return 0; -} -EXPORT_SYMBOL(tty_port_alloc_xmit_buf); - -void tty_port_free_xmit_buf(struct tty_port *port) -{ - mutex_lock(&port->buf_mutex); - if (port->xmit_buf != NULL) { - free_page((unsigned long)port->xmit_buf); - port->xmit_buf = NULL; - } - mutex_unlock(&port->buf_mutex); -} -EXPORT_SYMBOL(tty_port_free_xmit_buf); - -static void tty_port_destructor(struct kref *kref) -{ - struct tty_port *port = container_of(kref, struct tty_port, kref); - if (port->xmit_buf) - free_page((unsigned long)port->xmit_buf); - if (port->ops->destruct) - port->ops->destruct(port); - else - kfree(port); -} - -void tty_port_put(struct tty_port *port) -{ - if (port) - kref_put(&port->kref, tty_port_destructor); -} -EXPORT_SYMBOL(tty_port_put); - -/** - * tty_port_tty_get - get a tty reference - * @port: tty port - * - * Return a refcount protected tty instance or NULL if the port is not - * associated with a tty (eg due to close or hangup) - */ - -struct tty_struct *tty_port_tty_get(struct tty_port *port) -{ - unsigned long flags; - struct tty_struct *tty; - - spin_lock_irqsave(&port->lock, flags); - tty = tty_kref_get(port->tty); - spin_unlock_irqrestore(&port->lock, flags); - return tty; -} -EXPORT_SYMBOL(tty_port_tty_get); - -/** - * tty_port_tty_set - set the tty of a port - * @port: tty port - * @tty: the tty - * - * Associate the port and tty pair. Manages any internal refcounts. - * Pass NULL to deassociate a port - */ - -void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty) -{ - unsigned long flags; - - spin_lock_irqsave(&port->lock, flags); - if (port->tty) - tty_kref_put(port->tty); - port->tty = tty_kref_get(tty); - spin_unlock_irqrestore(&port->lock, flags); -} -EXPORT_SYMBOL(tty_port_tty_set); - -static void tty_port_shutdown(struct tty_port *port) -{ - mutex_lock(&port->mutex); - if (port->ops->shutdown && !port->console && - test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags)) - port->ops->shutdown(port); - mutex_unlock(&port->mutex); -} - -/** - * tty_port_hangup - hangup helper - * @port: tty port - * - * Perform port level tty hangup flag and count changes. Drop the tty - * reference. - */ - -void tty_port_hangup(struct tty_port *port) -{ - unsigned long flags; - - spin_lock_irqsave(&port->lock, flags); - port->count = 0; - port->flags &= ~ASYNC_NORMAL_ACTIVE; - if (port->tty) { - set_bit(TTY_IO_ERROR, &port->tty->flags); - tty_kref_put(port->tty); - } - port->tty = NULL; - spin_unlock_irqrestore(&port->lock, flags); - wake_up_interruptible(&port->open_wait); - wake_up_interruptible(&port->delta_msr_wait); - tty_port_shutdown(port); -} -EXPORT_SYMBOL(tty_port_hangup); - -/** - * tty_port_carrier_raised - carrier raised check - * @port: tty port - * - * Wrapper for the carrier detect logic. For the moment this is used - * to hide some internal details. This will eventually become entirely - * internal to the tty port. - */ - -int tty_port_carrier_raised(struct tty_port *port) -{ - if (port->ops->carrier_raised == NULL) - return 1; - return port->ops->carrier_raised(port); -} -EXPORT_SYMBOL(tty_port_carrier_raised); - -/** - * tty_port_raise_dtr_rts - Raise DTR/RTS - * @port: tty port - * - * Wrapper for the DTR/RTS raise logic. For the moment this is used - * to hide some internal details. This will eventually become entirely - * internal to the tty port. - */ - -void tty_port_raise_dtr_rts(struct tty_port *port) -{ - if (port->ops->dtr_rts) - port->ops->dtr_rts(port, 1); -} -EXPORT_SYMBOL(tty_port_raise_dtr_rts); - -/** - * tty_port_lower_dtr_rts - Lower DTR/RTS - * @port: tty port - * - * Wrapper for the DTR/RTS raise logic. For the moment this is used - * to hide some internal details. This will eventually become entirely - * internal to the tty port. - */ - -void tty_port_lower_dtr_rts(struct tty_port *port) -{ - if (port->ops->dtr_rts) - port->ops->dtr_rts(port, 0); -} -EXPORT_SYMBOL(tty_port_lower_dtr_rts); - -/** - * tty_port_block_til_ready - Waiting logic for tty open - * @port: the tty port being opened - * @tty: the tty device being bound - * @filp: the file pointer of the opener - * - * Implement the core POSIX/SuS tty behaviour when opening a tty device. - * Handles: - * - hangup (both before and during) - * - non blocking open - * - rts/dtr/dcd - * - signals - * - port flags and counts - * - * The passed tty_port must implement the carrier_raised method if it can - * do carrier detect and the dtr_rts method if it supports software - * management of these lines. Note that the dtr/rts raise is done each - * iteration as a hangup may have previously dropped them while we wait. - */ - -int tty_port_block_til_ready(struct tty_port *port, - struct tty_struct *tty, struct file *filp) -{ - int do_clocal = 0, retval; - unsigned long flags; - DEFINE_WAIT(wait); - int cd; - - /* block if port is in the process of being closed */ - if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) { - wait_event_interruptible_tty(port->close_wait, - !(port->flags & ASYNC_CLOSING)); - if (port->flags & ASYNC_HUP_NOTIFY) - return -EAGAIN; - else - return -ERESTARTSYS; - } - - /* if non-blocking mode is set we can pass directly to open unless - the port has just hung up or is in another error state */ - if (tty->flags & (1 << TTY_IO_ERROR)) { - port->flags |= ASYNC_NORMAL_ACTIVE; - return 0; - } - if (filp->f_flags & O_NONBLOCK) { - /* Indicate we are open */ - if (tty->termios->c_cflag & CBAUD) - tty_port_raise_dtr_rts(port); - port->flags |= ASYNC_NORMAL_ACTIVE; - return 0; - } - - if (C_CLOCAL(tty)) - do_clocal = 1; - - /* Block waiting until we can proceed. We may need to wait for the - carrier, but we must also wait for any close that is in progress - before the next open may complete */ - - retval = 0; - - /* The port lock protects the port counts */ - spin_lock_irqsave(&port->lock, flags); - if (!tty_hung_up_p(filp)) - port->count--; - port->blocked_open++; - spin_unlock_irqrestore(&port->lock, flags); - - while (1) { - /* Indicate we are open */ - if (tty->termios->c_cflag & CBAUD) - tty_port_raise_dtr_rts(port); - - prepare_to_wait(&port->open_wait, &wait, TASK_INTERRUPTIBLE); - /* Check for a hangup or uninitialised port. - Return accordingly */ - if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) { - if (port->flags & ASYNC_HUP_NOTIFY) - retval = -EAGAIN; - else - retval = -ERESTARTSYS; - break; - } - /* Probe the carrier. For devices with no carrier detect this - will always return true */ - cd = tty_port_carrier_raised(port); - if (!(port->flags & ASYNC_CLOSING) && - (do_clocal || cd)) - break; - if (signal_pending(current)) { - retval = -ERESTARTSYS; - break; - } - tty_unlock(); - schedule(); - tty_lock(); - } - finish_wait(&port->open_wait, &wait); - - /* Update counts. A parallel hangup will have set count to zero and - we must not mess that up further */ - spin_lock_irqsave(&port->lock, flags); - if (!tty_hung_up_p(filp)) - port->count++; - port->blocked_open--; - if (retval == 0) - port->flags |= ASYNC_NORMAL_ACTIVE; - spin_unlock_irqrestore(&port->lock, flags); - return retval; -} -EXPORT_SYMBOL(tty_port_block_til_ready); - -int tty_port_close_start(struct tty_port *port, - struct tty_struct *tty, struct file *filp) -{ - unsigned long flags; - - spin_lock_irqsave(&port->lock, flags); - if (tty_hung_up_p(filp)) { - spin_unlock_irqrestore(&port->lock, flags); - return 0; - } - - if (tty->count == 1 && port->count != 1) { - printk(KERN_WARNING - "tty_port_close_start: tty->count = 1 port count = %d.\n", - port->count); - port->count = 1; - } - if (--port->count < 0) { - printk(KERN_WARNING "tty_port_close_start: count = %d\n", - port->count); - port->count = 0; - } - - if (port->count) { - spin_unlock_irqrestore(&port->lock, flags); - if (port->ops->drop) - port->ops->drop(port); - return 0; - } - set_bit(ASYNCB_CLOSING, &port->flags); - tty->closing = 1; - spin_unlock_irqrestore(&port->lock, flags); - /* Don't block on a stalled port, just pull the chain */ - if (tty->flow_stopped) - tty_driver_flush_buffer(tty); - if (test_bit(ASYNCB_INITIALIZED, &port->flags) && - port->closing_wait != ASYNC_CLOSING_WAIT_NONE) - tty_wait_until_sent(tty, port->closing_wait); - if (port->drain_delay) { - unsigned int bps = tty_get_baud_rate(tty); - long timeout; - - if (bps > 1200) - timeout = max_t(long, - (HZ * 10 * port->drain_delay) / bps, HZ / 10); - else - timeout = 2 * HZ; - schedule_timeout_interruptible(timeout); - } - /* Flush the ldisc buffering */ - tty_ldisc_flush(tty); - - /* Drop DTR/RTS if HUPCL is set. This causes any attached modem to - hang up the line */ - if (tty->termios->c_cflag & HUPCL) - tty_port_lower_dtr_rts(port); - - /* Don't call port->drop for the last reference. Callers will want - to drop the last active reference in ->shutdown() or the tty - shutdown path */ - return 1; -} -EXPORT_SYMBOL(tty_port_close_start); - -void tty_port_close_end(struct tty_port *port, struct tty_struct *tty) -{ - unsigned long flags; - - spin_lock_irqsave(&port->lock, flags); - tty->closing = 0; - - if (port->blocked_open) { - spin_unlock_irqrestore(&port->lock, flags); - if (port->close_delay) { - msleep_interruptible( - jiffies_to_msecs(port->close_delay)); - } - spin_lock_irqsave(&port->lock, flags); - wake_up_interruptible(&port->open_wait); - } - port->flags &= ~(ASYNC_NORMAL_ACTIVE | ASYNC_CLOSING); - wake_up_interruptible(&port->close_wait); - spin_unlock_irqrestore(&port->lock, flags); -} -EXPORT_SYMBOL(tty_port_close_end); - -void tty_port_close(struct tty_port *port, struct tty_struct *tty, - struct file *filp) -{ - if (tty_port_close_start(port, tty, filp) == 0) - return; - tty_port_shutdown(port); - set_bit(TTY_IO_ERROR, &tty->flags); - tty_port_close_end(port, tty); - tty_port_tty_set(port, NULL); -} -EXPORT_SYMBOL(tty_port_close); - -int tty_port_open(struct tty_port *port, struct tty_struct *tty, - struct file *filp) -{ - spin_lock_irq(&port->lock); - if (!tty_hung_up_p(filp)) - ++port->count; - spin_unlock_irq(&port->lock); - tty_port_tty_set(port, tty); - - /* - * Do the device-specific open only if the hardware isn't - * already initialized. Serialize open and shutdown using the - * port mutex. - */ - - mutex_lock(&port->mutex); - - if (!test_bit(ASYNCB_INITIALIZED, &port->flags)) { - clear_bit(TTY_IO_ERROR, &tty->flags); - if (port->ops->activate) { - int retval = port->ops->activate(port, tty); - if (retval) { - mutex_unlock(&port->mutex); - return retval; - } - } - set_bit(ASYNCB_INITIALIZED, &port->flags); - } - mutex_unlock(&port->mutex); - return tty_port_block_til_ready(port, tty, filp); -} - -EXPORT_SYMBOL(tty_port_open); |
