xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

datagram: Add offset argument to __skb_recv_datagram

Browse Source 
This one is only considered for MSG_PEEK flag and the value pointed by
it specifies where to start peeking bytes from. If the offset happens to
point into the middle of the returned skb, the offset within this skb is
put back to this very argument.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Pavel Emelyanov
2012-02-21 07:30:58 +00:00
committed by David S. Miller
parent 4934b0329f
commit 3f518bf745
4 changed files with 18 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
net/core/datagram.c
View File

@@ -132,6 +132,8 @@ out_noerr:
* __skb_recv_datagram - Receive a datagram skbuff
* @sk: socket
* @flags: MSG_ flags
* @off: an offset in bytes to peek skb from. Returns an offset
* within an skb where data actually starts
* @peeked: returns non-zero if this packet has been seen before
* @err: error code returned
*
@@ -158,7 +160,7 @@ out_noerr:
* the standard around please.
*/
struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags,
int *peeked, int *err)
int *peeked, int *off, int *err)
{
struct sk_buff *skb;
long timeo;
@@ -183,20 +185,23 @@ struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags,
struct sk_buff_head *queue = &sk->sk_receive_queue;
spin_lock_irqsave(&queue->lock, cpu_flags);
skb = skb_peek(queue);
if (skb) {
skb_queue_walk(queue, skb) {
*peeked = skb->peeked;
if (flags & MSG_PEEK) {
if (*off >= skb->len) {
*off -= skb->len;
continue;
}
skb->peeked = 1;
atomic_inc(&skb->users);
} else
__skb_unlink(skb, queue);
spin_unlock_irqrestore(&queue->lock, cpu_flags);
return skb;
}
spin_unlock_irqrestore(&queue->lock, cpu_flags);
if (skb)
return skb;
/* User doesn't want to wait */
error = -EAGAIN;
if (!timeo)
@@ -215,10 +220,10 @@ EXPORT_SYMBOL(__skb_recv_datagram);
struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
int noblock, int *err)
{
int peeked;
int peeked, off = 0;
return __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
&peeked, err);
&peeked, &off, err);
}
EXPORT_SYMBOL(skb_recv_datagram);