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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/isdn/i4l/isdn_x25iface.c
downloadop-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/isdn/i4l/isdn_x25iface.c')
-rw-r--r--drivers/isdn/i4l/isdn_x25iface.c328
1 files changed, 328 insertions, 0 deletions
diff --git a/drivers/isdn/i4l/isdn_x25iface.c b/drivers/isdn/i4l/isdn_x25iface.c
new file mode 100644
index 0000000..4ab7600
--- /dev/null
+++ b/drivers/isdn/i4l/isdn_x25iface.c
@@ -0,0 +1,328 @@
+/* $Id: isdn_x25iface.c,v 1.1.2.2 2004/01/12 22:37:19 keil Exp $
+ *
+ * Linux ISDN subsystem, X.25 related functions
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ * stuff needed to support the Linux X.25 PLP code on top of devices that
+ * can provide a lab_b service using the concap_proto mechanism.
+ * This module supports a network interface wich provides lapb_sematics
+ * -- as defined in Documentation/networking/x25-iface.txt -- to
+ * the upper layer and assumes that the lower layer provides a reliable
+ * data link service by means of the concap_device_ops callbacks.
+ *
+ * Only protocol specific stuff goes here. Device specific stuff
+ * goes to another -- device related -- concap_proto support source file.
+ *
+ */
+
+/* #include <linux/isdn.h> */
+#include <linux/netdevice.h>
+#include <linux/concap.h>
+#include <linux/wanrouter.h>
+#include <net/x25device.h>
+#include "isdn_x25iface.h"
+
+/* for debugging messages not to cause an oops when device pointer is NULL*/
+#define MY_DEVNAME(dev) ( (dev) ? (dev)->name : "DEVICE UNSPECIFIED" )
+
+
+typedef struct isdn_x25iface_proto_data {
+ int magic;
+ enum wan_states state;
+ /* Private stuff, not to be accessed via proto_data. We provide the
+ other storage for the concap_proto instance here as well,
+ enabling us to allocate both with just one kmalloc(): */
+ struct concap_proto priv;
+} ix25_pdata_t;
+
+
+
+/* is now in header file (extern): struct concap_proto * isdn_x25iface_proto_new(void); */
+void isdn_x25iface_proto_del( struct concap_proto * );
+int isdn_x25iface_proto_close( struct concap_proto * );
+int isdn_x25iface_proto_restart( struct concap_proto *,
+ struct net_device *,
+ struct concap_device_ops *);
+int isdn_x25iface_xmit( struct concap_proto *, struct sk_buff * );
+int isdn_x25iface_receive( struct concap_proto *, struct sk_buff * );
+int isdn_x25iface_connect_ind( struct concap_proto * );
+int isdn_x25iface_disconn_ind( struct concap_proto * );
+
+
+static struct concap_proto_ops ix25_pops = {
+ &isdn_x25iface_proto_new,
+ &isdn_x25iface_proto_del,
+ &isdn_x25iface_proto_restart,
+ &isdn_x25iface_proto_close,
+ &isdn_x25iface_xmit,
+ &isdn_x25iface_receive,
+ &isdn_x25iface_connect_ind,
+ &isdn_x25iface_disconn_ind
+};
+
+/* error message helper function */
+static void illegal_state_warn( unsigned state, unsigned char firstbyte)
+{
+ printk( KERN_WARNING "isdn_x25iface: firstbyte %x illegal in"
+ "current state %d\n",firstbyte, state );
+}
+
+/* check protocol data field for consistency */
+static int pdata_is_bad( ix25_pdata_t * pda ){
+
+ if( pda && pda -> magic == ISDN_X25IFACE_MAGIC ) return 0;
+ printk( KERN_WARNING
+ "isdn_x25iface_xxx: illegal pointer to proto data\n" );
+ return 1;
+}
+
+/* create a new x25 interface protocol instance
+ */
+struct concap_proto * isdn_x25iface_proto_new(void)
+{
+ ix25_pdata_t * tmp = kmalloc(sizeof(ix25_pdata_t),GFP_KERNEL);
+ IX25DEBUG("isdn_x25iface_proto_new\n");
+ if( tmp ){
+ tmp -> magic = ISDN_X25IFACE_MAGIC;
+ tmp -> state = WAN_UNCONFIGURED;
+ /* private data space used to hold the concap_proto data.
+ Only to be accessed via the returned pointer */
+ spin_lock_init(&tmp->priv.lock);
+ tmp -> priv.dops = NULL;
+ tmp -> priv.net_dev = NULL;
+ tmp -> priv.pops = &ix25_pops;
+ tmp -> priv.flags = 0;
+ tmp -> priv.proto_data = tmp;
+ return( &(tmp -> priv) );
+ }
+ return NULL;
+};
+
+/* close the x25iface encapsulation protocol
+ */
+int isdn_x25iface_proto_close(struct concap_proto *cprot){
+
+ ix25_pdata_t *tmp;
+ int ret = 0;
+ ulong flags;
+
+ if( ! cprot ){
+ printk( KERN_ERR "isdn_x25iface_proto_close: "
+ "invalid concap_proto pointer\n" );
+ return -1;
+ }
+ IX25DEBUG( "isdn_x25iface_proto_close %s \n", MY_DEVNAME(cprot -> net_dev) );
+ spin_lock_irqsave(&cprot->lock, flags);
+ cprot -> dops = NULL;
+ cprot -> net_dev = NULL;
+ tmp = cprot -> proto_data;
+ if( pdata_is_bad( tmp ) ){
+ ret = -1;
+ } else {
+ tmp -> state = WAN_UNCONFIGURED;
+ }
+ spin_unlock_irqrestore(&cprot->lock, flags);
+ return ret;
+}
+
+/* Delete the x25iface encapsulation protocol instance
+ */
+void isdn_x25iface_proto_del(struct concap_proto *cprot){
+
+ ix25_pdata_t * tmp;
+
+ IX25DEBUG( "isdn_x25iface_proto_del \n" );
+ if( ! cprot ){
+ printk( KERN_ERR "isdn_x25iface_proto_del: "
+ "concap_proto pointer is NULL\n" );
+ return;
+ }
+ tmp = cprot -> proto_data;
+ if( tmp == NULL ){
+ printk( KERN_ERR "isdn_x25iface_proto_del: inconsistent "
+ "proto_data pointer (maybe already deleted?)\n");
+ return;
+ }
+ /* close if the protocol is still open */
+ if( cprot -> dops ) isdn_x25iface_proto_close(cprot);
+ /* freeing the storage should be sufficient now. But some additional
+ settings might help to catch wild pointer bugs */
+ tmp -> magic = 0;
+ cprot -> proto_data = NULL;
+
+ kfree( tmp );
+ return;
+}
+
+/* (re-)initialize the data structures for x25iface encapsulation
+ */
+int isdn_x25iface_proto_restart(struct concap_proto *cprot,
+ struct net_device *ndev,
+ struct concap_device_ops *dops)
+{
+ ix25_pdata_t * pda = cprot -> proto_data ;
+ ulong flags;
+
+ IX25DEBUG( "isdn_x25iface_proto_restart %s \n", MY_DEVNAME(ndev) );
+
+ if ( pdata_is_bad( pda ) ) return -1;
+
+ if( !( dops && dops -> data_req && dops -> connect_req
+ && dops -> disconn_req ) ){
+ printk( KERN_WARNING "isdn_x25iface_restart: required dops"
+ " missing\n" );
+ isdn_x25iface_proto_close(cprot);
+ return -1;
+ }
+ spin_lock_irqsave(&cprot->lock, flags);
+ cprot -> net_dev = ndev;
+ cprot -> pops = &ix25_pops;
+ cprot -> dops = dops;
+ pda -> state = WAN_DISCONNECTED;
+ spin_unlock_irqrestore(&cprot->lock, flags);
+ return 0;
+}
+
+/* deliver a dl_data frame received from i4l HL driver to the network layer
+ */
+int isdn_x25iface_receive(struct concap_proto *cprot, struct sk_buff *skb)
+{
+ IX25DEBUG( "isdn_x25iface_receive %s \n", MY_DEVNAME(cprot->net_dev) );
+ if ( ( (ix25_pdata_t*) (cprot->proto_data) )
+ -> state == WAN_CONNECTED ){
+ if( skb_push(skb, 1)){
+ skb -> data[0]=0x00;
+ skb->protocol = x25_type_trans(skb, cprot->net_dev);
+ netif_rx(skb);
+ return 0;
+ }
+ }
+ printk(KERN_WARNING "isdn_x25iface_receive %s: not connected, skb dropped\n", MY_DEVNAME(cprot->net_dev) );
+ dev_kfree_skb(skb);
+ return -1;
+}
+
+/* a connection set up is indicated by lower layer
+ */
+int isdn_x25iface_connect_ind(struct concap_proto *cprot)
+{
+ struct sk_buff * skb = dev_alloc_skb(1);
+ enum wan_states *state_p
+ = &( ( (ix25_pdata_t*) (cprot->proto_data) ) -> state);
+ IX25DEBUG( "isdn_x25iface_connect_ind %s \n"
+ , MY_DEVNAME(cprot->net_dev) );
+ if( *state_p == WAN_UNCONFIGURED ){
+ printk(KERN_WARNING
+ "isdn_x25iface_connect_ind while unconfigured %s\n"
+ , MY_DEVNAME(cprot->net_dev) );
+ return -1;
+ }
+ *state_p = WAN_CONNECTED;
+ if( skb ){
+ *( skb_put(skb, 1) ) = 0x01;
+ skb->protocol = x25_type_trans(skb, cprot->net_dev);
+ netif_rx(skb);
+ return 0;
+ } else {
+ printk(KERN_WARNING "isdn_x25iface_connect_ind: "
+ " out of memory -- disconnecting\n");
+ cprot -> dops -> disconn_req(cprot);
+ return -1;
+ }
+}
+
+/* a disconnect is indicated by lower layer
+ */
+int isdn_x25iface_disconn_ind(struct concap_proto *cprot)
+{
+ struct sk_buff *skb;
+ enum wan_states *state_p
+ = &( ( (ix25_pdata_t*) (cprot->proto_data) ) -> state);
+ IX25DEBUG( "isdn_x25iface_disconn_ind %s \n", MY_DEVNAME(cprot -> net_dev) );
+ if( *state_p == WAN_UNCONFIGURED ){
+ printk(KERN_WARNING
+ "isdn_x25iface_disconn_ind while unconfigured\n");
+ return -1;
+ }
+ if(! cprot -> net_dev) return -1;
+ *state_p = WAN_DISCONNECTED;
+ skb = dev_alloc_skb(1);
+ if( skb ){
+ *( skb_put(skb, 1) ) = 0x02;
+ skb->protocol = x25_type_trans(skb, cprot->net_dev);
+ netif_rx(skb);
+ return 0;
+ } else {
+ printk(KERN_WARNING "isdn_x25iface_disconn_ind:"
+ " out of memory\n");
+ return -1;
+ }
+}
+
+/* process a frame handed over to us from linux network layer. First byte
+ semantics as defined in Documentation/networking/x25-iface.txt
+ */
+int isdn_x25iface_xmit(struct concap_proto *cprot, struct sk_buff *skb)
+{
+ unsigned char firstbyte = skb->data[0];
+ enum wan_states *state = &((ix25_pdata_t*)cprot->proto_data)->state;
+ int ret = 0;
+ IX25DEBUG( "isdn_x25iface_xmit: %s first=%x state=%d \n", MY_DEVNAME(cprot -> net_dev), firstbyte, *state );
+ switch ( firstbyte ){
+ case 0x00: /* dl_data request */
+ if( *state == WAN_CONNECTED ){
+ skb_pull(skb, 1);
+ cprot -> net_dev -> trans_start = jiffies;
+ ret = ( cprot -> dops -> data_req(cprot, skb) );
+ /* prepare for future retransmissions */
+ if( ret ) skb_push(skb,1);
+ return ret;
+ }
+ illegal_state_warn( *state, firstbyte );
+ break;
+ case 0x01: /* dl_connect request */
+ if( *state == WAN_DISCONNECTED ){
+ *state = WAN_CONNECTING;
+ ret = cprot -> dops -> connect_req(cprot);
+ if(ret){
+ /* reset state and notify upper layer about
+ * immidiatly failed attempts */
+ isdn_x25iface_disconn_ind(cprot);
+ }
+ } else {
+ illegal_state_warn( *state, firstbyte );
+ }
+ break;
+ case 0x02: /* dl_disconnect request */
+ switch ( *state ){
+ case WAN_DISCONNECTED:
+ /* Should not happen. However, give upper layer a
+ chance to recover from inconstistency but don't
+ trust the lower layer sending the disconn_confirm
+ when already disconnected */
+ printk(KERN_WARNING "isdn_x25iface_xmit: disconnect "
+ " requested while disconnected\n" );
+ isdn_x25iface_disconn_ind(cprot);
+ break; /* prevent infinite loops */
+ case WAN_CONNECTING:
+ case WAN_CONNECTED:
+ *state = WAN_DISCONNECTED;
+ cprot -> dops -> disconn_req(cprot);
+ break;
+ default:
+ illegal_state_warn( *state, firstbyte );
+ }
+ break;
+ case 0x03: /* changing lapb parameters requested */
+ printk(KERN_WARNING "isdn_x25iface_xmit: setting of lapb"
+ " options not yet supported\n");
+ break;
+ default:
+ printk(KERN_WARNING "isdn_x25iface_xmit: frame with illegal"
+ " first byte %x ignored:\n", firstbyte);
+ }
+ dev_kfree_skb(skb);
+ return 0;
+}
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