net: Walk fragments in __skb_splice_bits

Add walking of fragments in __skb_splice_bits.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tom Herbert 2016-03-07 14:11:04 -08:00 committed by David S. Miller
parent f092276d85
commit fa9835e52e

View File

@ -1918,6 +1918,7 @@ static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe,
struct splice_pipe_desc *spd, struct sock *sk)
{
int seg;
struct sk_buff *iter;
/* map the linear part :
* If skb->head_frag is set, this 'linear' part is backed by a
@ -1944,6 +1945,19 @@ static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe,
return true;
}
skb_walk_frags(skb, iter) {
if (*offset >= iter->len) {
*offset -= iter->len;
continue;
}
/* __skb_splice_bits() only fails if the output has no room
* left, so no point in going over the frag_list for the error
* case.
*/
if (__skb_splice_bits(iter, pipe, offset, len, spd, sk))
return true;
}
return false;
}
@ -1970,9 +1984,7 @@ ssize_t skb_socket_splice(struct sock *sk,
/*
* Map data from the skb to a pipe. Should handle both the linear part,
* the fragments, and the frag list. It does NOT handle frag lists within
* the frag list, if such a thing exists. We'd probably need to recurse to
* handle that cleanly.
* the fragments, and the frag list.
*/
int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
struct pipe_inode_info *pipe, unsigned int tlen,
@ -1991,29 +2003,10 @@ int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
.ops = &nosteal_pipe_buf_ops,
.spd_release = sock_spd_release,
};
struct sk_buff *frag_iter;
int ret = 0;
/*
* __skb_splice_bits() only fails if the output has no room left,
* so no point in going over the frag_list for the error case.
*/
if (__skb_splice_bits(skb, pipe, &offset, &tlen, &spd, sk))
goto done;
else if (!tlen)
goto done;
__skb_splice_bits(skb, pipe, &offset, &tlen, &spd, sk);
/*
* now see if we have a frag_list to map
*/
skb_walk_frags(skb, frag_iter) {
if (!tlen)
break;
if (__skb_splice_bits(frag_iter, pipe, &offset, &tlen, &spd, sk))
break;
}
done:
if (spd.nr_pages)
ret = splice_cb(sk, pipe, &spd);