unsigned int minor;
struct dentry *capifs_dentry;
- struct capi20_appl *ap;
- u32 ncci;
- u16 datahandle;
- u16 msgid;
+ struct capi20_appl *ap;
+ u32 ncci;
+ atomic_t datahandle;
+ atomic_t msgid;
struct tty_port port;
int ttyinstop;
int ttyoutstop;
- struct sk_buff *ttyskb;
- struct sk_buff_head inqueue;
- int inbytes;
- struct sk_buff_head outqueue;
- int outbytes;
+ struct sk_buff_head inqueue;
+
+ struct sk_buff_head outqueue;
+ int outbytes;
+ struct sk_buff *outskb;
+ spinlock_t outlock;
/* transmit path */
struct list_head ackqueue;
spinlock_t ackqlock;
};
-/* FIXME: The following lock is a sledgehammer-workaround to a
- * locking issue with the capiminor (and maybe other) data structure(s).
- * Access to this data is done in a racy way and crashes the machine with
- * a FritzCard DSL driver; sooner or later. This is a workaround
- * which trades scalability vs stability, so it doesn't crash the kernel anymore.
- * The correct (and scalable) fix for the issue seems to require
- * an API change to the drivers... . */
-static DEFINE_SPINLOCK(workaround_lock);
-
struct capincci {
struct list_head list;
u32 ncci;
static int capiminor_add_ack(struct capiminor *mp, u16 datahandle)
{
struct ackqueue_entry *n;
- unsigned long flags;
n = kmalloc(sizeof(*n), GFP_ATOMIC);
if (unlikely(!n)) {
}
n->datahandle = datahandle;
INIT_LIST_HEAD(&n->list);
- spin_lock_irqsave(&mp->ackqlock, flags);
+ spin_lock_bh(&mp->ackqlock);
list_add_tail(&n->list, &mp->ackqueue);
mp->nack++;
- spin_unlock_irqrestore(&mp->ackqlock, flags);
+ spin_unlock_bh(&mp->ackqlock);
return 0;
}
static int capiminor_del_ack(struct capiminor *mp, u16 datahandle)
{
struct ackqueue_entry *p, *tmp;
- unsigned long flags;
- spin_lock_irqsave(&mp->ackqlock, flags);
+ spin_lock_bh(&mp->ackqlock);
list_for_each_entry_safe(p, tmp, &mp->ackqueue, list) {
if (p->datahandle == datahandle) {
list_del(&p->list);
- kfree(p);
mp->nack--;
- spin_unlock_irqrestore(&mp->ackqlock, flags);
+ spin_unlock_bh(&mp->ackqlock);
+ kfree(p);
return 0;
}
}
- spin_unlock_irqrestore(&mp->ackqlock, flags);
+ spin_unlock_bh(&mp->ackqlock);
return -1;
}
static void capiminor_del_all_ack(struct capiminor *mp)
{
struct ackqueue_entry *p, *tmp;
- unsigned long flags;
- spin_lock_irqsave(&mp->ackqlock, flags);
list_for_each_entry_safe(p, tmp, &mp->ackqueue, list) {
list_del(&p->list);
kfree(p);
mp->nack--;
}
- spin_unlock_irqrestore(&mp->ackqlock, flags);
}
mp->ap = ap;
mp->ncci = ncci;
- mp->msgid = 0;
INIT_LIST_HEAD(&mp->ackqueue);
spin_lock_init(&mp->ackqlock);
skb_queue_head_init(&mp->inqueue);
skb_queue_head_init(&mp->outqueue);
+ spin_lock_init(&mp->outlock);
tty_port_init(&mp->port);
mp->port.ops = &capiminor_port_ops;
{
struct capiminor *mp = container_of(kref, struct capiminor, kref);
- kfree_skb(mp->ttyskb);
+ kfree_skb(mp->outskb);
skb_queue_purge(&mp->inqueue);
skb_queue_purge(&mp->outqueue);
capiminor_del_all_ack(mp);
gen_data_b3_resp_for(struct capiminor *mp, struct sk_buff *skb)
{
struct sk_buff *nskb;
- nskb = alloc_skb(CAPI_DATA_B3_RESP_LEN, GFP_ATOMIC);
+ nskb = alloc_skb(CAPI_DATA_B3_RESP_LEN, GFP_KERNEL);
if (nskb) {
u16 datahandle = CAPIMSG_U16(skb->data,CAPIMSG_BASELEN+4+4+2);
unsigned char *s = skb_put(nskb, CAPI_DATA_B3_RESP_LEN);
capimsg_setu16(s, 2, mp->ap->applid);
capimsg_setu8 (s, 4, CAPI_DATA_B3);
capimsg_setu8 (s, 5, CAPI_RESP);
- capimsg_setu16(s, 6, mp->msgid++);
+ capimsg_setu16(s, 6, atomic_inc_return(&mp->msgid));
capimsg_setu32(s, 8, mp->ncci);
capimsg_setu16(s, 12, datahandle);
}
static void handle_minor_recv(struct capiminor *mp)
{
struct sk_buff *skb;
- while ((skb = skb_dequeue(&mp->inqueue)) != NULL) {
- unsigned int len = skb->len;
- mp->inbytes -= len;
+
+ while ((skb = skb_dequeue(&mp->inqueue)) != NULL)
if (handle_recv_skb(mp, skb) < 0) {
skb_queue_head(&mp->inqueue, skb);
- mp->inbytes += len;
return;
}
- }
}
-static int handle_minor_send(struct capiminor *mp)
+static void handle_minor_send(struct capiminor *mp)
{
struct tty_struct *tty;
struct sk_buff *skb;
u16 len;
- int count = 0;
u16 errcode;
u16 datahandle;
tty = tty_port_tty_get(&mp->port);
if (!tty)
- return 0;
+ return;
if (mp->ttyoutstop) {
#if defined(_DEBUG_DATAFLOW) || defined(_DEBUG_TTYFUNCS)
printk(KERN_DEBUG "capi: send: tty stopped\n");
#endif
tty_kref_put(tty);
- return 0;
+ return;
}
- while ((skb = skb_dequeue(&mp->outqueue)) != NULL) {
- datahandle = mp->datahandle;
+ while (1) {
+ spin_lock_bh(&mp->outlock);
+ skb = __skb_dequeue(&mp->outqueue);
+ if (!skb) {
+ spin_unlock_bh(&mp->outlock);
+ break;
+ }
len = (u16)skb->len;
+ mp->outbytes -= len;
+ spin_unlock_bh(&mp->outlock);
+
+ datahandle = atomic_inc_return(&mp->datahandle);
skb_push(skb, CAPI_DATA_B3_REQ_LEN);
memset(skb->data, 0, CAPI_DATA_B3_REQ_LEN);
capimsg_setu16(skb->data, 0, CAPI_DATA_B3_REQ_LEN);
capimsg_setu16(skb->data, 2, mp->ap->applid);
capimsg_setu8 (skb->data, 4, CAPI_DATA_B3);
capimsg_setu8 (skb->data, 5, CAPI_REQ);
- capimsg_setu16(skb->data, 6, mp->msgid++);
+ capimsg_setu16(skb->data, 6, atomic_inc_return(&mp->msgid));
capimsg_setu32(skb->data, 8, mp->ncci); /* NCCI */
capimsg_setu32(skb->data, 12, (u32)(long)skb->data);/* Data32 */
capimsg_setu16(skb->data, 16, len); /* Data length */
if (capiminor_add_ack(mp, datahandle) < 0) {
skb_pull(skb, CAPI_DATA_B3_REQ_LEN);
- skb_queue_head(&mp->outqueue, skb);
- tty_kref_put(tty);
- return count;
+
+ spin_lock_bh(&mp->outlock);
+ __skb_queue_head(&mp->outqueue, skb);
+ mp->outbytes += len;
+ spin_unlock_bh(&mp->outlock);
+
+ break;
}
errcode = capi20_put_message(mp->ap, skb);
if (errcode == CAPI_NOERROR) {
- mp->datahandle++;
- count++;
- mp->outbytes -= len;
#ifdef _DEBUG_DATAFLOW
printk(KERN_DEBUG "capi: DATA_B3_REQ %u len=%u\n",
datahandle, len);
if (errcode == CAPI_SENDQUEUEFULL) {
skb_pull(skb, CAPI_DATA_B3_REQ_LEN);
- skb_queue_head(&mp->outqueue, skb);
+
+ spin_lock_bh(&mp->outlock);
+ __skb_queue_head(&mp->outqueue, skb);
+ mp->outbytes += len;
+ spin_unlock_bh(&mp->outlock);
+
break;
}
/* ups, drop packet */
printk(KERN_ERR "capi: put_message = %x\n", errcode);
- mp->outbytes -= len;
kfree_skb(skb);
}
tty_kref_put(tty);
- return count;
}
#endif /* CONFIG_ISDN_CAPI_MIDDLEWARE */
u16 datahandle;
#endif /* CONFIG_ISDN_CAPI_MIDDLEWARE */
struct capincci *np;
- unsigned long flags;
mutex_lock(&cdev->lock);
if (CAPIMSG_CMD(skb->data) == CAPI_CONNECT_B3_IND)
capincci_alloc(cdev, CAPIMSG_NCCI(skb->data));
- spin_lock_irqsave(&workaround_lock, flags);
if (CAPIMSG_COMMAND(skb->data) != CAPI_DATA_B3) {
skb_queue_tail(&cdev->recvqueue, skb);
wake_up_interruptible(&cdev->recvwait);
datahandle, skb->len-CAPIMSG_LEN(skb->data));
#endif
skb_queue_tail(&mp->inqueue, skb);
- mp->inbytes += skb->len;
+
handle_minor_recv(mp);
} else if (CAPIMSG_SUBCOMMAND(skb->data) == CAPI_CONF) {
CAPIMSG_U16(skb->data, CAPIMSG_BASELEN+4+2));
#endif
kfree_skb(skb);
- (void)capiminor_del_ack(mp, datahandle);
+ capiminor_del_ack(mp, datahandle);
tty = tty_port_tty_get(&mp->port);
if (tty) {
tty_wakeup(tty);
tty_kref_put(tty);
}
- (void)handle_minor_send(mp);
+ handle_minor_send(mp);
} else {
/* ups, let capi application handle it :-) */
#endif /* CONFIG_ISDN_CAPI_MIDDLEWARE */
unlock_out:
- spin_unlock_irqrestore(&workaround_lock, flags);
mutex_unlock(&cdev->lock);
}
static int capinc_tty_open(struct tty_struct *tty, struct file *filp)
{
struct capiminor *mp = tty->driver_data;
- unsigned long flags;
int err;
err = tty_port_open(&mp->port, tty, filp);
if (err)
return err;
- spin_lock_irqsave(&workaround_lock, flags);
handle_minor_recv(mp);
- spin_unlock_irqrestore(&workaround_lock, flags);
return 0;
}
{
struct capiminor *mp = tty->driver_data;
struct sk_buff *skb;
- unsigned long flags;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_write(count=%d)\n", count);
#endif
- spin_lock_irqsave(&workaround_lock, flags);
- skb = mp->ttyskb;
+ spin_lock_bh(&mp->outlock);
+ skb = mp->outskb;
if (skb) {
- mp->ttyskb = NULL;
- skb_queue_tail(&mp->outqueue, skb);
+ mp->outskb = NULL;
+ __skb_queue_tail(&mp->outqueue, skb);
mp->outbytes += skb->len;
}
skb = alloc_skb(CAPI_DATA_B3_REQ_LEN+count, GFP_ATOMIC);
if (!skb) {
printk(KERN_ERR "capinc_tty_write: alloc_skb failed\n");
- spin_unlock_irqrestore(&workaround_lock, flags);
+ spin_unlock_bh(&mp->outlock);
return -ENOMEM;
}
skb_reserve(skb, CAPI_DATA_B3_REQ_LEN);
memcpy(skb_put(skb, count), buf, count);
- skb_queue_tail(&mp->outqueue, skb);
+ __skb_queue_tail(&mp->outqueue, skb);
mp->outbytes += skb->len;
- (void)handle_minor_send(mp);
- spin_unlock_irqrestore(&workaround_lock, flags);
+ spin_unlock_bh(&mp->outlock);
+
+ handle_minor_send(mp);
+
return count;
}
static int capinc_tty_put_char(struct tty_struct *tty, unsigned char ch)
{
struct capiminor *mp = tty->driver_data;
+ bool invoke_send = false;
struct sk_buff *skb;
- unsigned long flags;
int ret = 1;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_put_char(%u)\n", ch);
#endif
- spin_lock_irqsave(&workaround_lock, flags);
- skb = mp->ttyskb;
+ spin_lock_bh(&mp->outlock);
+ skb = mp->outskb;
if (skb) {
if (skb_tailroom(skb) > 0) {
*(skb_put(skb, 1)) = ch;
- spin_unlock_irqrestore(&workaround_lock, flags);
- return 1;
+ goto unlock_out;
}
- mp->ttyskb = NULL;
- skb_queue_tail(&mp->outqueue, skb);
+ mp->outskb = NULL;
+ __skb_queue_tail(&mp->outqueue, skb);
mp->outbytes += skb->len;
- (void)handle_minor_send(mp);
+ invoke_send = true;
}
+
skb = alloc_skb(CAPI_DATA_B3_REQ_LEN+CAPI_MAX_BLKSIZE, GFP_ATOMIC);
if (skb) {
skb_reserve(skb, CAPI_DATA_B3_REQ_LEN);
*(skb_put(skb, 1)) = ch;
- mp->ttyskb = skb;
+ mp->outskb = skb;
} else {
printk(KERN_ERR "capinc_put_char: char %u lost\n", ch);
ret = 0;
}
- spin_unlock_irqrestore(&workaround_lock, flags);
+
+unlock_out:
+ spin_unlock_bh(&mp->outlock);
+
+ if (invoke_send)
+ handle_minor_send(mp);
+
return ret;
}
{
struct capiminor *mp = tty->driver_data;
struct sk_buff *skb;
- unsigned long flags;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_flush_chars\n");
#endif
- spin_lock_irqsave(&workaround_lock, flags);
- skb = mp->ttyskb;
+ spin_lock_bh(&mp->outlock);
+ skb = mp->outskb;
if (skb) {
- mp->ttyskb = NULL;
- skb_queue_tail(&mp->outqueue, skb);
+ mp->outskb = NULL;
+ __skb_queue_tail(&mp->outqueue, skb);
mp->outbytes += skb->len;
- (void)handle_minor_send(mp);
- }
- (void)handle_minor_recv(mp);
- spin_unlock_irqrestore(&workaround_lock, flags);
+ spin_unlock_bh(&mp->outlock);
+
+ handle_minor_send(mp);
+ } else
+ spin_unlock_bh(&mp->outlock);
+
+ handle_minor_recv(mp);
}
static int capinc_tty_write_room(struct tty_struct *tty)
static void capinc_tty_unthrottle(struct tty_struct *tty)
{
struct capiminor *mp = tty->driver_data;
- unsigned long flags;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_unthrottle\n");
#endif
- spin_lock_irqsave(&workaround_lock, flags);
mp->ttyinstop = 0;
handle_minor_recv(mp);
- spin_unlock_irqrestore(&workaround_lock, flags);
}
static void capinc_tty_stop(struct tty_struct *tty)
static void capinc_tty_start(struct tty_struct *tty)
{
struct capiminor *mp = tty->driver_data;
- unsigned long flags;
#ifdef _DEBUG_TTYFUNCS
printk(KERN_DEBUG "capinc_tty_start\n");
#endif
- spin_lock_irqsave(&workaround_lock, flags);
mp->ttyoutstop = 0;
- (void)handle_minor_send(mp);
- spin_unlock_irqrestore(&workaround_lock, flags);
+ handle_minor_send(mp);
}
static void capinc_tty_hangup(struct tty_struct *tty)
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff