diff options
author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2015-05-21 17:00:00 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2015-05-25 00:06:59 -0400 |
commit | a60e3cc7c92973a31fad0fd04dc5cf4355d3d1ef (patch) | |
tree | fccece19424d49db1c03ef8f204f3c7ca3478a4a /net | |
parent | 869e7c62486ec0e170a9771acaa251d1a33b5871 (diff) | |
download | linux-a60e3cc7c92973a31fad0fd04dc5cf4355d3d1ef.tar.bz2 |
net: make skb_splice_bits more configureable
Prepare skb_splice_bits to be able to deal with AF_UNIX sockets.
AF_UNIX sockets don't use lock_sock/release_sock and thus we have to
use a callback to make the locking and unlocking configureable.
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r-- | net/core/skbuff.c | 45 | ||||
-rw-r--r-- | net/ipv4/tcp.c | 5 |
2 files changed, 31 insertions, 19 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 4f2babeaf18d..02769fa4f5c8 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1870,15 +1870,39 @@ static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe, return false; } +ssize_t skb_socket_splice(struct sock *sk, + struct pipe_inode_info *pipe, + struct splice_pipe_desc *spd) +{ + int ret; + + /* Drop the socket lock, otherwise we have reverse + * locking dependencies between sk_lock and i_mutex + * here as compared to sendfile(). We enter here + * with the socket lock held, and splice_to_pipe() will + * grab the pipe inode lock. For sendfile() emulation, + * we call into ->sendpage() with the i_mutex lock held + * and networking will grab the socket lock. + */ + release_sock(sk); + ret = splice_to_pipe(pipe, spd); + lock_sock(sk); + + return ret; +} + /* * 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. */ -int skb_splice_bits(struct sk_buff *skb, unsigned int offset, +int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset, struct pipe_inode_info *pipe, unsigned int tlen, - unsigned int flags) + unsigned int flags, + ssize_t (*splice_cb)(struct sock *, + struct pipe_inode_info *, + struct splice_pipe_desc *)) { struct partial_page partial[MAX_SKB_FRAGS]; struct page *pages[MAX_SKB_FRAGS]; @@ -1891,7 +1915,6 @@ int skb_splice_bits(struct sk_buff *skb, unsigned int offset, .spd_release = sock_spd_release, }; struct sk_buff *frag_iter; - struct sock *sk = skb->sk; int ret = 0; /* @@ -1914,20 +1937,8 @@ int skb_splice_bits(struct sk_buff *skb, unsigned int offset, } done: - if (spd.nr_pages) { - /* - * Drop the socket lock, otherwise we have reverse - * locking dependencies between sk_lock and i_mutex - * here as compared to sendfile(). We enter here - * with the socket lock held, and splice_to_pipe() will - * grab the pipe inode lock. For sendfile() emulation, - * we call into ->sendpage() with the i_mutex lock held - * and networking will grab the socket lock. - */ - release_sock(sk); - ret = splice_to_pipe(pipe, &spd); - lock_sock(sk); - } + if (spd.nr_pages) + ret = splice_cb(sk, pipe, &spd); return ret; } diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 90afcec3f427..65f791f74845 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -695,8 +695,9 @@ static int tcp_splice_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, struct tcp_splice_state *tss = rd_desc->arg.data; int ret; - ret = skb_splice_bits(skb, offset, tss->pipe, min(rd_desc->count, len), - tss->flags); + ret = skb_splice_bits(skb, skb->sk, offset, tss->pipe, + min(rd_desc->count, len), tss->flags, + skb_socket_splice); if (ret > 0) rd_desc->count -= ret; return ret; |