Commit bc9540c6 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: splice: fix __splice_segment() 



commit 9ca1b22d (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: default avatarEric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 82bda619

net/core/skbuff.c

+15 −13
Original line number Diff line number Diff line
@@ -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);

	do {

		unsigned int flen = min(*len, plen);



	if (spd_fill_page(spd, pipe, page, &flen, poff, skb, linear, sk))

		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;

	}

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