diff options
Diffstat (limited to 'net/atm/ipcommon.c')
| -rw-r--r-- | net/atm/ipcommon.c | 35 |
1 files changed, 24 insertions, 11 deletions
diff --git a/net/atm/ipcommon.c b/net/atm/ipcommon.c index d7c4a4d3a..707b74fb6 100644 --- a/net/atm/ipcommon.c +++ b/net/atm/ipcommon.c @@ -3,6 +3,7 @@ /* Written 1996-2000 by Werner Almesberger, EPFL LRC/ICA */ +#include <linux/module.h> #include <linux/string.h> #include <linux/skbuff.h> #include <linux/netdevice.h> @@ -31,7 +32,11 @@ const unsigned char llc_oui[] = { /* - * skb_migrate moves the list at FROM to TO, emptying FROM in the process. + * skb_migrate appends the list at "from" to "to", emptying "from" in the + * process. skb_migrate is atomic with respect to all other skb operations on + * "from" and "to". Note that it locks both lists at the same time, so beware + * of potential deadlocks. + * * This function should live in skbuff.c or skbuff.h. */ @@ -40,18 +45,26 @@ void skb_migrate(struct sk_buff_head *from,struct sk_buff_head *to) { struct sk_buff *skb; unsigned long flags; + struct sk_buff *skb_from = (struct sk_buff *) from; + struct sk_buff *skb_to = (struct sk_buff *) to; + struct sk_buff *prev; spin_lock_irqsave(&from->lock,flags); - *to = *from; - from->prev = (struct sk_buff *) from; - from->next = (struct sk_buff *) from; + spin_lock(&to->lock); + prev = from->prev; + from->next->prev = to->prev; + prev->next = skb_to; + to->prev->next = from->next; + to->prev = from->prev; + for (skb = from->next; skb != skb_to; skb = skb->next) + skb->list = to; + to->qlen += from->qlen; + spin_unlock(&to->lock); + from->prev = skb_from; + from->next = skb_from; from->qlen = 0; spin_unlock_irqrestore(&from->lock,flags); - spin_lock_init(&to->lock); - for (skb = ((struct sk_buff *) to)->next; - skb != (struct sk_buff *) from; skb = skb->next) skb->list = to; - if (to->next == (struct sk_buff *) from) - to->next = (struct sk_buff *) to; - to->next->prev = (struct sk_buff *) to; - to->prev->next = (struct sk_buff *) to; } + + +EXPORT_SYMBOL(skb_migrate); |