leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

skb: api to report errors for zero copy skbs

Browse Source 
Orphaning frags for zero copy skbs needs to allocate data in atomic
context so is has a chance to fail. If it does we currently discard
the skb which is safe, but we don't report anything to the caller,
so it can not recover by e.g. disabling zero copy.

Add an API to free skb reporting such errors: this is used
by tun in case orphaning frags fails.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Michael S. Tsirkin 2012-11-01 09:16:28 +00:00 committed by David S. Miller
parent e19d6763cc
commit 25121173f7
2 changed files with 21 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/skbuff.h
View File

@ -568,6 +568,7 @@ static inline struct rtable *skb_rtable(const struct sk_buff *skb)
} }
extern void kfree_skb(struct sk_buff *skb); extern void kfree_skb(struct sk_buff *skb);
extern void skb_tx_error(struct sk_buff *skb);
extern void consume_skb(struct sk_buff *skb); extern void consume_skb(struct sk_buff *skb);
extern void __kfree_skb(struct sk_buff *skb); extern void __kfree_skb(struct sk_buff *skb);
extern struct kmem_cache *skbuff_head_cache; extern struct kmem_cache *skbuff_head_cache;

20
net/core/skbuff.c
View File

@ -634,6 +634,26 @@ void kfree_skb(struct sk_buff *skb)
} }
EXPORT_SYMBOL(kfree_skb); EXPORT_SYMBOL(kfree_skb);
/**
* skb_tx_error - report an sk_buff xmit error
* @skb: buffer that triggered an error
*
* Report xmit error if a device callback is tracking this skb.
* skb must be freed afterwards.
*/
void skb_tx_error(struct sk_buff *skb)
{
if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
struct ubuf_info *uarg;
uarg = skb_shinfo(skb)->destructor_arg;
if (uarg->callback)
uarg->callback(uarg, false);
skb_shinfo(skb)->tx_flags &= ~SKBTX_DEV_ZEROCOPY;
}
}
EXPORT_SYMBOL(skb_tx_error);
/** /**
* consume_skb - free an skbuff * consume_skb - free an skbuff
* @skb: buffer to free * @skb: buffer to free