From bc9540c637c3d8712ccbf9dcf28621f380ed5e64 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 11 Jan 2013 14:46:37 +0000 Subject: [PATCH] net: splice: fix __splice_segment() commit 9ca1b22d6d2 (net: splice: avoid high order page splitting) forgot that skb->head could need a copy into several page frags. This could be the case for loopback traffic mostly. Also remove now useless skb argument from linear_to_page() and __splice_segment() prototypes. Signed-off-by: Eric Dumazet Cc: Willy Tarreau Signed-off-by: David S. Miller --- net/core/skbuff.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index f5dfdf7..a9a2ae3 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1649,7 +1649,7 @@ static void sock_spd_release(struct splice_pipe_desc *spd, unsigned int i) static struct page *linear_to_page(struct page *page, unsigned int *len, unsigned int *offset, - struct sk_buff *skb, struct sock *sk) + struct sock *sk) { struct page_frag *pfrag = sk_page_frag(sk); @@ -1682,14 +1682,14 @@ static bool spd_can_coalesce(const struct splice_pipe_desc *spd, static bool spd_fill_page(struct splice_pipe_desc *spd, struct pipe_inode_info *pipe, struct page *page, unsigned int *len, unsigned int offset, - struct sk_buff *skb, bool linear, + bool linear, struct sock *sk) { if (unlikely(spd->nr_pages == MAX_SKB_FRAGS)) return true; if (linear) { - page = linear_to_page(page, len, &offset, skb, sk); + page = linear_to_page(page, len, &offset, sk); if (!page) return true; } @@ -1708,13 +1708,11 @@ static bool spd_fill_page(struct splice_pipe_desc *spd, static bool __splice_segment(struct page *page, unsigned int poff, unsigned int plen, unsigned int *off, - unsigned int *len, struct sk_buff *skb, + unsigned int *len, struct splice_pipe_desc *spd, bool linear, struct sock *sk, struct pipe_inode_info *pipe) { - unsigned int flen; - if (!*len) return true; @@ -1729,12 +1727,16 @@ static bool __splice_segment(struct page *page, unsigned int poff, plen -= *off; *off = 0; - flen = min(*len, plen); - - if (spd_fill_page(spd, pipe, page, &flen, poff, skb, linear, sk)) - return true; + do { + unsigned int flen = min(*len, plen); - *len -= flen; + if (spd_fill_page(spd, pipe, page, &flen, poff, + linear, sk)) + return true; + poff += flen; + plen -= flen; + *len -= flen; + } while (*len && plen); return false; } @@ -1757,7 +1759,7 @@ static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe, if (__splice_segment(virt_to_page(skb->data), (unsigned long) skb->data & (PAGE_SIZE - 1), skb_headlen(skb), - offset, len, skb, spd, + offset, len, spd, skb_head_is_locked(skb), sk, pipe)) return true; @@ -1770,7 +1772,7 @@ static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe, if (__splice_segment(skb_frag_page(f), f->page_offset, skb_frag_size(f), - offset, len, skb, spd, false, sk, pipe)) + offset, len, spd, false, sk, pipe)) return true; } -- 2.7.4