diff options
Diffstat (limited to 'drivers/char/hvc_iucv.c')
| -rw-r--r-- | drivers/char/hvc_iucv.c | 420 |
1 files changed, 270 insertions, 150 deletions
diff --git a/drivers/char/hvc_iucv.c b/drivers/char/hvc_iucv.c index 5ea7d77..a534968 100644 --- a/drivers/char/hvc_iucv.c +++ b/drivers/char/hvc_iucv.c @@ -1,26 +1,30 @@ /* - * hvc_iucv.c - z/VM IUCV back-end for the Hypervisor Console (HVC) + * hvc_iucv.c - z/VM IUCV hypervisor console (HVC) device driver * - * This back-end for HVC provides terminal access via + * This HVC device driver provides terminal access using * z/VM IUCV communication paths. * - * Copyright IBM Corp. 2008. + * Copyright IBM Corp. 2008 * * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com> */ #define KMSG_COMPONENT "hvc_iucv" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt #include <linux/types.h> #include <asm/ebcdic.h> +#include <linux/delay.h> +#include <linux/init.h> #include <linux/mempool.h> #include <linux/module.h> #include <linux/tty.h> +#include <linux/wait.h> #include <net/iucv/iucv.h> #include "hvc_console.h" -/* HVC backend for z/VM IUCV */ +/* General device driver settings */ #define HVC_IUCV_MAGIC 0xc9e4c3e5 #define MAX_HVC_IUCV_LINES HVC_ALLOC_TTY_ADAPTERS #define MEMPOOL_MIN_NR (PAGE_SIZE / sizeof(struct iucv_tty_buffer)/4) @@ -33,14 +37,14 @@ #define MSG_TYPE_WINSIZE 0x08 /* Terminal window size update */ #define MSG_TYPE_DATA 0x10 /* Terminal data */ -#define MSG_SIZE(s) ((s) + offsetof(struct iucv_tty_msg, data)) struct iucv_tty_msg { u8 version; /* Message version */ u8 type; /* Message type */ -#define MSG_MAX_DATALEN (~(u16)0) +#define MSG_MAX_DATALEN ((u16)(~0)) u16 datalen; /* Payload length */ u8 data[]; /* Payload buffer */ } __attribute__((packed)); +#define MSG_SIZE(s) ((s) + offsetof(struct iucv_tty_msg, data)) enum iucv_state_t { IUCV_DISCONN = 0, @@ -54,19 +58,26 @@ enum tty_state_t { }; struct hvc_iucv_private { - struct hvc_struct *hvc; /* HVC console struct reference */ + struct hvc_struct *hvc; /* HVC struct reference */ u8 srv_name[8]; /* IUCV service name (ebcdic) */ + unsigned char is_console; /* Linux console usage flag */ enum iucv_state_t iucv_state; /* IUCV connection status */ enum tty_state_t tty_state; /* TTY status */ struct iucv_path *path; /* IUCV path pointer */ spinlock_t lock; /* hvc_iucv_private lock */ +#define SNDBUF_SIZE (PAGE_SIZE) /* must be < MSG_MAX_DATALEN */ + void *sndbuf; /* send buffer */ + size_t sndbuf_len; /* length of send buffer */ +#define QUEUE_SNDBUF_DELAY (HZ / 25) + struct delayed_work sndbuf_work; /* work: send iucv msg(s) */ + wait_queue_head_t sndbuf_waitq; /* wait for send completion */ struct list_head tty_outqueue; /* outgoing IUCV messages */ struct list_head tty_inqueue; /* incoming IUCV messages */ }; struct iucv_tty_buffer { struct list_head list; /* list pointer */ - struct iucv_message msg; /* store an incoming IUCV message */ + struct iucv_message msg; /* store an IUCV message */ size_t offset; /* data buffer offset */ struct iucv_tty_msg *mbuf; /* buffer to store input/output data */ }; @@ -78,11 +89,12 @@ static void hvc_iucv_msg_pending(struct iucv_path *, struct iucv_message *); static void hvc_iucv_msg_complete(struct iucv_path *, struct iucv_message *); -/* Kernel module parameters */ -static unsigned long hvc_iucv_devices; +/* Kernel module parameter: use one terminal device as default */ +static unsigned long hvc_iucv_devices = 1; /* Array of allocated hvc iucv tty lines... */ static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES]; +#define IUCV_HVC_CON_IDX (0) /* Kmem cache and mempool for iucv_tty_buffer elements */ static struct kmem_cache *hvc_iucv_buffer_cache; @@ -112,7 +124,7 @@ struct hvc_iucv_private *hvc_iucv_get_private(uint32_t num) } /** - * alloc_tty_buffer() - Returns a new struct iucv_tty_buffer element. + * alloc_tty_buffer() - Return a new struct iucv_tty_buffer element. * @size: Size of the internal buffer used to store data. * @flags: Memory allocation flags passed to mempool. * @@ -120,7 +132,6 @@ struct hvc_iucv_private *hvc_iucv_get_private(uint32_t num) * allocates an internal data buffer with the specified size @size. * Note: The total message size arises from the internal buffer size and the * members of the iucv_tty_msg structure. - * * The function returns NULL if memory allocation has failed. */ static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags) @@ -130,7 +141,7 @@ static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags) bufp = mempool_alloc(hvc_iucv_mempool, flags); if (!bufp) return NULL; - memset(bufp, 0, sizeof(struct iucv_tty_buffer)); + memset(bufp, 0, sizeof(*bufp)); if (size > 0) { bufp->msg.length = MSG_SIZE(size); @@ -149,9 +160,6 @@ static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags) /** * destroy_tty_buffer() - destroy struct iucv_tty_buffer element. * @bufp: Pointer to a struct iucv_tty_buffer element, SHALL NOT be NULL. - * - * The destroy_tty_buffer() function frees the internal data buffer and returns - * the struct iucv_tty_buffer element back to the mempool for freeing. */ static void destroy_tty_buffer(struct iucv_tty_buffer *bufp) { @@ -161,11 +169,7 @@ static void destroy_tty_buffer(struct iucv_tty_buffer *bufp) /** * destroy_tty_buffer_list() - call destroy_tty_buffer() for each list element. - * @list: List head pointer to a list containing struct iucv_tty_buffer - * elements. - * - * Calls destroy_tty_buffer() for each struct iucv_tty_buffer element in the - * list @list. + * @list: List containing struct iucv_tty_buffer elements. */ static void destroy_tty_buffer_list(struct list_head *list) { @@ -178,24 +182,24 @@ static void destroy_tty_buffer_list(struct list_head *list) } /** - * hvc_iucv_write() - Receive IUCV message write data to HVC console buffer. - * @priv: Pointer to hvc_iucv_private structure. - * @buf: HVC console buffer for writing received terminal data. - * @count: HVC console buffer size. + * hvc_iucv_write() - Receive IUCV message & write data to HVC buffer. + * @priv: Pointer to struct hvc_iucv_private + * @buf: HVC buffer for writing received terminal data. + * @count: HVC buffer size. * @has_more_data: Pointer to an int variable. * * The function picks up pending messages from the input queue and receives * the message data that is then written to the specified buffer @buf. - * If the buffer size @count is less than the data message size, then the + * If the buffer size @count is less than the data message size, the * message is kept on the input queue and @has_more_data is set to 1. - * If the message data has been entirely written, the message is removed from + * If all message data has been written, the message is removed from * the input queue. * * The function returns the number of bytes written to the terminal, zero if * there are no pending data messages available or if there is no established * IUCV path. * If the IUCV path has been severed, then -EPIPE is returned to cause a - * hang up (that is issued by the HVC console layer). + * hang up (that is issued by the HVC layer). */ static int hvc_iucv_write(struct hvc_iucv_private *priv, char *buf, int count, int *has_more_data) @@ -204,12 +208,12 @@ static int hvc_iucv_write(struct hvc_iucv_private *priv, int written; int rc; - /* Immediately return if there is no IUCV connection */ + /* immediately return if there is no IUCV connection */ if (priv->iucv_state == IUCV_DISCONN) return 0; - /* If the IUCV path has been severed, return -EPIPE to inform the - * hvc console layer to hang up the tty device. */ + /* if the IUCV path has been severed, return -EPIPE to inform the + * HVC layer to hang up the tty device. */ if (priv->iucv_state == IUCV_SEVERED) return -EPIPE; @@ -217,7 +221,7 @@ static int hvc_iucv_write(struct hvc_iucv_private *priv, if (list_empty(&priv->tty_inqueue)) return 0; - /* receive a iucv message and flip data to the tty (ldisc) */ + /* receive an iucv message and flip data to the tty (ldisc) */ rb = list_first_entry(&priv->tty_inqueue, struct iucv_tty_buffer, list); written = 0; @@ -260,7 +264,7 @@ static int hvc_iucv_write(struct hvc_iucv_private *priv, case MSG_TYPE_WINSIZE: if (rb->mbuf->datalen != sizeof(struct winsize)) break; - hvc_resize(priv->hvc, *((struct winsize *)rb->mbuf->data)); + hvc_resize(priv->hvc, *((struct winsize *) rb->mbuf->data)); break; case MSG_TYPE_ERROR: /* ignored ... */ @@ -284,10 +288,9 @@ out_written: * @buf: Pointer to a buffer to store data * @count: Size of buffer available for writing * - * The hvc_console thread calls this method to read characters from - * the terminal backend. If an IUCV communication path has been established, - * pending IUCV messages are received and data is copied into buffer @buf - * up to @count bytes. + * The HVC thread calls this method to read characters from the back-end. + * If an IUCV communication path has been established, pending IUCV messages + * are received and data is copied into buffer @buf up to @count bytes. * * Locking: The routine gets called under an irqsave() spinlock; and * the routine locks the struct hvc_iucv_private->lock to call @@ -318,66 +321,122 @@ static int hvc_iucv_get_chars(uint32_t vtermno, char *buf, int count) } /** - * hvc_iucv_send() - Send an IUCV message containing terminal data. + * hvc_iucv_queue() - Buffer terminal data for sending. * @priv: Pointer to struct hvc_iucv_private instance. * @buf: Buffer containing data to send. - * @size: Size of buffer and amount of data to send. + * @count: Size of buffer and amount of data to send. + * + * The function queues data for sending. To actually send the buffered data, + * a work queue function is scheduled (with QUEUE_SNDBUF_DELAY). + * The function returns the number of data bytes that has been buffered. * - * If an IUCV communication path is established, the function copies the buffer - * data to a newly allocated struct iucv_tty_buffer element, sends the data and - * puts the element to the outqueue. + * If the device is not connected, data is ignored and the function returns + * @count. + * If the buffer is full, the function returns 0. + * If an existing IUCV communicaton path has been severed, -EPIPE is returned + * (that can be passed to HVC layer to cause a tty hangup). + */ +static int hvc_iucv_queue(struct hvc_iucv_private *priv, const char *buf, + int count) +{ + size_t len; + + if (priv->iucv_state == IUCV_DISCONN) + return count; /* ignore data */ + + if (priv->iucv_state == IUCV_SEVERED) + return -EPIPE; + + len = min_t(size_t, count, SNDBUF_SIZE - priv->sndbuf_len); + if (!len) + return 0; + + memcpy(priv->sndbuf + priv->sndbuf_len, buf, len); + priv->sndbuf_len += len; + + if (priv->iucv_state == IUCV_CONNECTED) + schedule_delayed_work(&priv->sndbuf_work, QUEUE_SNDBUF_DELAY); + + return len; +} + +/** + * hvc_iucv_send() - Send an IUCV message containing terminal data. + * @priv: Pointer to struct hvc_iucv_private instance. * - * If there is no IUCV communication path established, the function returns 0. - * If an existing IUCV communicaton path has been severed, the function returns - * -EPIPE (can be passed to HVC layer to cause a tty hangup). + * If an IUCV communication path has been established, the buffered output data + * is sent via an IUCV message and the number of bytes sent is returned. + * Returns 0 if there is no established IUCV communication path or + * -EPIPE if an existing IUCV communicaton path has been severed. */ -static int hvc_iucv_send(struct hvc_iucv_private *priv, const char *buf, - int count) +static int hvc_iucv_send(struct hvc_iucv_private *priv) { struct iucv_tty_buffer *sb; - int rc; - u16 len; + int rc, len; if (priv->iucv_state == IUCV_SEVERED) return -EPIPE; if (priv->iucv_state == IUCV_DISCONN) - return 0; + return -EIO; - len = min_t(u16, MSG_MAX_DATALEN, count); + if (!priv->sndbuf_len) + return 0; /* allocate internal buffer to store msg data and also compute total * message length */ - sb = alloc_tty_buffer(len, GFP_ATOMIC); + sb = alloc_tty_buffer(priv->sndbuf_len, GFP_ATOMIC); if (!sb) return -ENOMEM; - sb->mbuf->datalen = len; - memcpy(sb->mbuf->data, buf, len); + memcpy(sb->mbuf->data, priv->sndbuf, priv->sndbuf_len); + sb->mbuf->datalen = (u16) priv->sndbuf_len; + sb->msg.length = MSG_SIZE(sb->mbuf->datalen); list_add_tail(&sb->list, &priv->tty_outqueue); rc = __iucv_message_send(priv->path, &sb->msg, 0, 0, (void *) sb->mbuf, sb->msg.length); if (rc) { + /* drop the message here; however we might want to handle + * 0x03 (msg limit reached) by trying again... */ list_del(&sb->list); destroy_tty_buffer(sb); - len = 0; } + len = priv->sndbuf_len; + priv->sndbuf_len = 0; return len; } /** + * hvc_iucv_sndbuf_work() - Send buffered data over IUCV + * @work: Work structure. + * + * This work queue function sends buffered output data over IUCV and, + * if not all buffered data could be sent, reschedules itself. + */ +static void hvc_iucv_sndbuf_work(struct work_struct *work) +{ + struct hvc_iucv_private *priv; + + priv = container_of(work, struct hvc_iucv_private, sndbuf_work.work); + if (!priv) + return; + + spin_lock_bh(&priv->lock); + hvc_iucv_send(priv); + spin_unlock_bh(&priv->lock); +} + +/** * hvc_iucv_put_chars() - HVC put_chars operation. * @vtermno: HVC virtual terminal number. * @buf: Pointer to an buffer to read data from * @count: Size of buffer available for reading * - * The hvc_console thread calls this method to write characters from - * to the terminal backend. - * The function calls hvc_iucv_send() under the lock of the - * struct hvc_iucv_private instance that corresponds to the tty @vtermno. + * The HVC thread calls this method to write characters to the back-end. + * The function calls hvc_iucv_queue() to queue terminal data for sending. * * Locking: The method gets called under an irqsave() spinlock; and * locks struct hvc_iucv_private->lock. @@ -385,7 +444,7 @@ static int hvc_iucv_send(struct hvc_iucv_private *priv, const char *buf, static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count) { struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno); - int sent; + int queued; if (count <= 0) return 0; @@ -394,10 +453,10 @@ static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count) return -ENODEV; spin_lock(&priv->lock); - sent = hvc_iucv_send(priv, buf, count); + queued = hvc_iucv_queue(priv, buf, count); spin_unlock(&priv->lock); - return sent; + return queued; } /** @@ -406,7 +465,7 @@ static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count) * @id: Additional data (originally passed to hvc_alloc): the index of an struct * hvc_iucv_private instance. * - * The function sets the tty state to TTY_OPEN for the struct hvc_iucv_private + * The function sets the tty state to TTY_OPENED for the struct hvc_iucv_private * instance that is derived from @id. Always returns 0. * * Locking: struct hvc_iucv_private->lock, spin_lock_bh @@ -427,12 +486,8 @@ static int hvc_iucv_notifier_add(struct hvc_struct *hp, int id) } /** - * hvc_iucv_cleanup() - Clean up function if the tty portion is finally closed. + * hvc_iucv_cleanup() - Clean up and reset a z/VM IUCV HVC instance. * @priv: Pointer to the struct hvc_iucv_private instance. - * - * The functions severs the established IUCV communication path (if any), and - * destroy struct iucv_tty_buffer elements from the in- and outqueue. Finally, - * the functions resets the states to TTY_CLOSED and IUCV_DISCONN. */ static void hvc_iucv_cleanup(struct hvc_iucv_private *priv) { @@ -441,25 +496,62 @@ static void hvc_iucv_cleanup(struct hvc_iucv_private *priv) priv->tty_state = TTY_CLOSED; priv->iucv_state = IUCV_DISCONN; + + priv->sndbuf_len = 0; } /** - * hvc_iucv_notifier_hangup() - HVC notifier for tty hangups. - * @hp: Pointer to the HVC device (struct hvc_struct) - * @id: Additional data (originally passed to hvc_alloc): the index of an struct - * hvc_iucv_private instance. + * tty_outqueue_empty() - Test if the tty outq is empty + * @priv: Pointer to struct hvc_iucv_private instance. + */ +static inline int tty_outqueue_empty(struct hvc_iucv_private *priv) +{ + int rc; + + spin_lock_bh(&priv->lock); + rc = list_empty(&priv->tty_outqueue); + spin_unlock_bh(&priv->lock); + + return rc; +} + +/** + * flush_sndbuf_sync() - Flush send buffer and wait for completion + * @priv: Pointer to struct hvc_iucv_private instance. * - * This routine notifies the HVC backend that a tty hangup (carrier loss, - * virtual or otherwise) has occured. + * The routine cancels a pending sndbuf work, calls hvc_iucv_send() + * to flush any buffered terminal output data and waits for completion. + */ +static void flush_sndbuf_sync(struct hvc_iucv_private *priv) +{ + int sync_wait; + + cancel_delayed_work_sync(&priv->sndbuf_work); + + spin_lock_bh(&priv->lock); + hvc_iucv_send(priv); /* force sending buffered data */ + sync_wait = !list_empty(&priv->tty_outqueue); /* anything queued ? */ + spin_unlock_bh(&priv->lock); + + if (sync_wait) + wait_event_timeout(priv->sndbuf_waitq, + tty_outqueue_empty(priv), HZ); +} + +/** + * hvc_iucv_notifier_hangup() - HVC notifier for TTY hangups. + * @hp: Pointer to the HVC device (struct hvc_struct) + * @id: Additional data (originally passed to hvc_alloc): + * the index of an struct hvc_iucv_private instance. * - * The HVC backend for z/VM IUCV ignores virtual hangups (vhangup()), to keep - * an existing IUCV communication path established. + * This routine notifies the HVC back-end that a tty hangup (carrier loss, + * virtual or otherwise) has occured. + * The z/VM IUCV HVC device driver ignores virtual hangups (vhangup()) + * to keep an existing IUCV communication path established. * (Background: vhangup() is called from user space (by getty or login) to * disable writing to the tty by other applications). - * - * If the tty has been opened (e.g. getty) and an established IUCV path has been - * severed (we caused the tty hangup in that case), then the functions invokes - * hvc_iucv_cleanup() to clean up. + * If the tty has been opened and an established IUCV path has been severed + * (we caused the tty hangup), the function calls hvc_iucv_cleanup(). * * Locking: struct hvc_iucv_private->lock */ @@ -471,12 +563,12 @@ static void hvc_iucv_notifier_hangup(struct hvc_struct *hp, int id) if (!priv) return; + flush_sndbuf_sync(priv); + spin_lock_bh(&priv->lock); /* NOTE: If the hangup was scheduled by ourself (from the iucv - * path_servered callback [IUCV_SEVERED]), then we have to - * finally clean up the tty backend structure and set state to - * TTY_CLOSED. - * + * path_servered callback [IUCV_SEVERED]), we have to clean up + * our structure and to set state to TTY_CLOSED. * If the tty was hung up otherwise (e.g. vhangup()), then we * ignore this hangup and keep an established IUCV path open... * (...the reason is that we are not able to connect back to the @@ -494,10 +586,9 @@ static void hvc_iucv_notifier_hangup(struct hvc_struct *hp, int id) * @id: Additional data (originally passed to hvc_alloc): * the index of an struct hvc_iucv_private instance. * - * This routine notifies the HVC backend that the last tty device file - * descriptor has been closed. - * The function calls hvc_iucv_cleanup() to clean up the struct hvc_iucv_private - * instance. + * This routine notifies the HVC back-end that the last tty device fd has been + * closed. The function calls hvc_iucv_cleanup() to clean up the struct + * hvc_iucv_private instance. * * Locking: struct hvc_iucv_private->lock */ @@ -510,6 +601,8 @@ static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id) if (!priv) return; + flush_sndbuf_sync(priv); + spin_lock_bh(&priv->lock); path = priv->path; /* save reference to IUCV path */ priv->path = NULL; @@ -527,20 +620,18 @@ static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id) /** * hvc_iucv_path_pending() - IUCV handler to process a connection request. * @path: Pending path (struct iucv_path) - * @ipvmid: Originator z/VM system identifier + * @ipvmid: z/VM system identifier of originator * @ipuser: User specified data for this path * (AF_IUCV: port/service name and originator port) * - * The function uses the @ipuser data to check to determine if the pending - * path belongs to a terminal managed by this HVC backend. - * If the check is successful, then an additional check is done to ensure - * that a terminal cannot be accessed multiple times (only one connection - * to a terminal is allowed). In that particular case, the pending path is - * severed. If it is the first connection, the pending path is accepted and - * associated to the struct hvc_iucv_private. The iucv state is updated to - * reflect that a communication path has been established. + * The function uses the @ipuser data to determine if the pending path belongs + * to a terminal managed by this device driver. + * If the path belongs to this driver, ensure that the terminal is not accessed + * multiple times (only one connection to a terminal is allowed). + * If the terminal is not yet connected, the pending path is accepted and is + * associated to the appropriate struct hvc_iucv_private instance. * - * Returns 0 if the path belongs to a terminal managed by the this HVC backend; + * Returns 0 if @path belongs to a terminal managed by the this device driver; * otherwise returns -ENODEV in order to dispatch this path to other handlers. * * Locking: struct hvc_iucv_private->lock @@ -559,7 +650,6 @@ static int hvc_iucv_path_pending(struct iucv_path *path, priv = hvc_iucv_table[i]; break; } - if (!priv) return -ENODEV; @@ -588,6 +678,9 @@ static int hvc_iucv_path_pending(struct iucv_path *path, priv->path = path; priv->iucv_state = IUCV_CONNECTED; + /* flush buffered output data... */ + schedule_delayed_work(&priv->sndbuf_work, 5); + out_path_handled: spin_unlock(&priv->lock); return 0; @@ -603,8 +696,7 @@ out_path_handled: * sets the iucv state to IUCV_SEVERED for the associated struct * hvc_iucv_private instance. Later, the IUCV_SEVERED state triggers a tty * hangup (hvc_iucv_get_chars() / hvc_iucv_write()). - * - * If tty portion of the HVC is closed then clean up the outqueue in addition. + * If tty portion of the HVC is closed, clean up the outqueue. * * Locking: struct hvc_iucv_private->lock */ @@ -615,15 +707,25 @@ static void hvc_iucv_path_severed(struct iucv_path *path, u8 ipuser[16]) spin_lock(&priv->lock); priv->iucv_state = IUCV_SEVERED; - /* NOTE: If the tty has not yet been opened by a getty program - * (e.g. to see console messages), then cleanup the - * hvc_iucv_private structure to allow re-connects. + /* If the tty has not yet been opened, clean up the hvc_iucv_private + * structure to allow re-connects. + * This is also done for our console device because console hangups + * are handled specially and no notifier is called by HVC. + * The tty session is active (TTY_OPEN) and ready for re-connects... * - * If the tty has been opened, the get_chars() callback returns - * -EPIPE to signal the hvc console layer to hang up the tty. */ + * If it has been opened, let get_chars() return -EPIPE to signal the + * HVC layer to hang up the tty. + * If so, we need to wake up the HVC thread to call get_chars()... + */ priv->path = NULL; if (priv->tty_state == TTY_CLOSED) hvc_iucv_cleanup(priv); + else + if (priv->is_console) { + hvc_iucv_cleanup(priv); + priv->tty_state = TTY_OPENED; + } else + hvc_kick(); spin_unlock(&priv->lock); /* finally sever path (outside of priv->lock due to lock ordering) */ @@ -636,9 +738,9 @@ static void hvc_iucv_path_severed(struct iucv_path *path, u8 ipuser[16]) * @path: Pending path (struct iucv_path) * @msg: Pointer to the IUCV message * - * The function stores an incoming message on the input queue for later + * The function puts an incoming message on the input queue for later * processing (by hvc_iucv_get_chars() / hvc_iucv_write()). - * However, if the tty has not yet been opened, the message is rejected. + * If the tty has not yet been opened, the message is rejected. * * Locking: struct hvc_iucv_private->lock */ @@ -648,6 +750,12 @@ static void hvc_iucv_msg_pending(struct iucv_path *path, struct hvc_iucv_private *priv = path->private; struct iucv_tty_buffer *rb; + /* reject messages that exceed max size of iucv_tty_msg->datalen */ + if (msg->length > MSG_SIZE(MSG_MAX_DATALEN)) { + iucv_message_reject(path, msg); + return; + } + spin_lock(&priv->lock); /* reject messages if tty has not yet been opened */ @@ -656,7 +764,7 @@ static void hvc_iucv_msg_pending(struct iucv_path *path, goto unlock_return; } - /* allocate buffer an empty buffer element */ + /* allocate tty buffer to save iucv msg only */ rb = alloc_tty_buffer(0, GFP_ATOMIC); if (!rb) { iucv_message_reject(path, msg); @@ -666,7 +774,7 @@ static void hvc_iucv_msg_pending(struct iucv_path *path, list_add_tail(&rb->list, &priv->tty_inqueue); - hvc_kick(); /* wakup hvc console thread */ + hvc_kick(); /* wake up hvc thread */ unlock_return: spin_unlock(&priv->lock); @@ -677,10 +785,10 @@ unlock_return: * @path: Pending path (struct iucv_path) * @msg: Pointer to the IUCV message * - * The function is called upon completion of message delivery and the - * message is removed from the outqueue. Additional delivery information - * can be found in msg->audit: rejected messages (0x040000 (IPADRJCT)) and - * purged messages (0x010000 (IPADPGNR)). + * The function is called upon completion of message delivery to remove the + * message from the outqueue. Additional delivery information can be found + * msg->audit: rejected messages (0x040000 (IPADRJCT)), and + * purged messages (0x010000 (IPADPGNR)). * * Locking: struct hvc_iucv_private->lock */ @@ -697,6 +805,7 @@ static void hvc_iucv_msg_complete(struct iucv_path *path, list_move(&ent->list, &list_remove); break; } + wake_up(&priv->sndbuf_waitq); spin_unlock(&priv->lock); destroy_tty_buffer_list(&list_remove); } @@ -713,13 +822,14 @@ static struct hv_ops hvc_iucv_ops = { /** * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance - * @id: hvc_iucv_table index + * @id: hvc_iucv_table index + * @is_console: Flag if the instance is used as Linux console * - * This function allocates a new hvc_iucv_private struct and put the - * instance into hvc_iucv_table at index @id. + * This function allocates a new hvc_iucv_private structure and stores + * the instance in hvc_iucv_table at index @id. * Returns 0 on success; otherwise non-zero. */ -static int __init hvc_iucv_alloc(int id) +static int __init hvc_iucv_alloc(int id, unsigned int is_console) { struct hvc_iucv_private *priv; char name[9]; @@ -732,18 +842,33 @@ static int __init hvc_iucv_alloc(int id) spin_lock_init(&priv->lock); INIT_LIST_HEAD(&priv->tty_outqueue); INIT_LIST_HEAD(&priv->tty_inqueue); + INIT_DELAYED_WORK(&priv->sndbuf_work, hvc_iucv_sndbuf_work); + init_waitqueue_head(&priv->sndbuf_waitq); + + priv->sndbuf = (void *) get_zeroed_page(GFP_KERNEL); + if (!priv->sndbuf) { + kfree(priv); + return -ENOMEM; + } + + /* set console flag */ + priv->is_console = is_console; - /* Finally allocate hvc */ - priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, - HVC_IUCV_MAGIC + id, &hvc_iucv_ops, PAGE_SIZE); + /* finally allocate hvc */ + priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /* PAGE_SIZE */ + HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256); if (IS_ERR(priv->hvc)) { rc = PTR_ERR(priv->hvc); + free_page((unsigned long) priv->sndbuf); kfree(priv); return rc; } + /* notify HVC thread instead of using polling */ + priv->hvc->irq_requested = 1; + /* setup iucv related information */ - snprintf(name, 9, "ihvc%-4d", id); + snprintf(name, 9, "lnxhvc%-2d", id); memcpy(priv->srv_name, name, 8); ASCEBC(priv->srv_name, 8); @@ -752,15 +877,16 @@ static int __init hvc_iucv_alloc(int id) } /** - * hvc_iucv_init() - Initialization of HVC backend for z/VM IUCV + * hvc_iucv_init() - z/VM IUCV HVC device driver initialization */ static int __init hvc_iucv_init(void) { - int rc, i; + int rc; + unsigned int i; if (!MACHINE_IS_VM) { - pr_warning("The z/VM IUCV Hypervisor console cannot be " - "used without z/VM.\n"); + pr_info("The z/VM IUCV HVC device driver cannot " + "be used without z/VM\n"); return -ENODEV; } @@ -774,26 +900,33 @@ static int __init hvc_iucv_init(void) sizeof(struct iucv_tty_buffer), 0, 0, NULL); if (!hvc_iucv_buffer_cache) { - pr_err("Not enough memory for driver initialization " - "(rs=%d).\n", 1); + pr_err("Allocating memory failed with reason code=%d\n", 1); return -ENOMEM; } hvc_iucv_mempool = mempool_create_slab_pool(MEMPOOL_MIN_NR, hvc_iucv_buffer_cache); if (!hvc_iucv_mempool) { - pr_err("Not enough memory for driver initialization " - "(rs=%d).\n", 2); + pr_err("Allocating memory failed with reason code=%d\n", 2); kmem_cache_destroy(hvc_iucv_buffer_cache); return -ENOMEM; } + /* register the first terminal device as console + * (must be done before allocating hvc terminal devices) */ + rc = hvc_instantiate(HVC_IUCV_MAGIC, IUCV_HVC_CON_IDX, &hvc_iucv_ops); + if (rc) { + pr_err("Registering HVC terminal device as " + "Linux console failed\n"); + goto out_error_memory; + } + /* allocate hvc_iucv_private structs */ for (i = 0; i < hvc_iucv_devices; i++) { - rc = hvc_iucv_alloc(i); + rc = hvc_iucv_alloc(i, (i == IUCV_HVC_CON_IDX) ? 1 : 0); if (rc) { - pr_err("Could not create new z/VM IUCV HVC backend " - "rc=%d.\n", rc); + pr_err("Creating a new HVC terminal device " + "failed with error code=%d\n", rc); goto out_error_hvc; } } @@ -801,7 +934,8 @@ static int __init hvc_iucv_init(void) /* register IUCV callback handler */ rc = iucv_register(&hvc_iucv_handler, 0); if (rc) { - pr_err("Could not register iucv handler (rc=%d).\n", rc); + pr_err("Registering IUCV handlers failed with error code=%d\n", + rc); goto out_error_iucv; } @@ -816,22 +950,13 @@ out_error_hvc: hvc_remove(hvc_iucv_table[i]->hvc); kfree(hvc_iucv_table[i]); } +out_error_memory: mempool_destroy(hvc_iucv_mempool); kmem_cache_destroy(hvc_iucv_buffer_cache); return rc; } /** - * hvc_iucv_console_init() - Early console initialization - */ -static int __init hvc_iucv_console_init(void) -{ - if (!MACHINE_IS_VM || !hvc_iucv_devices) - return -ENODEV; - return hvc_instantiate(HVC_IUCV_MAGIC, 0, &hvc_iucv_ops); -} - -/** * hvc_iucv_config() - Parsing of hvc_iucv= kernel command line parameter * @val: Parameter value (numeric) */ @@ -841,10 +966,5 @@ static int __init hvc_iucv_config(char *val) } -module_init(hvc_iucv_init); -console_initcall(hvc_iucv_console_init); +device_initcall(hvc_iucv_init); __setup("hvc_iucv=", hvc_iucv_config); - -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("HVC back-end for z/VM IUCV."); -MODULE_AUTHOR("Hendrik Brueckner <brueckner@linux.vnet.ibm.com>"); |
