From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: [PATCH v3 4/6] net: only allow paged fragments with the same destructor to be coalesced. Date: Wed, 25 Jan 2012 12:27:12 +0000 Message-ID: <1327494434-21566-4-git-send-email-ian.campbell@citrix.com> References: <1327494389.24561.316.camel@zakaz.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ian Campbell , "David S. Miller" , Alexey Kuznetsov , "Pekka Savola (ipv6)" , James Morris , Hideaki YOSHIFUJI , Patrick McHardy , Eric Dumazet , =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= To: netdev@vger.kernel.org Return-path: Received: from smtp.citrix.com ([66.165.176.89]:40838 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753078Ab2AYM10 (ORCPT ); Wed, 25 Jan 2012 07:27:26 -0500 In-Reply-To: <1327494389.24561.316.camel@zakaz.uk.xensource.com> Sender: netdev-owner@vger.kernel.org List-ID: Signed-off-by: Ian Campbell Cc: "David S. Miller" Cc: Alexey Kuznetsov Cc: "Pekka Savola (ipv6)" Cc: James Morris Cc: Hideaki YOSHIFUJI Cc: Patrick McHardy Cc: Eric Dumazet Cc: "Micha=C5=82 Miros=C5=82aw" Cc: netdev@vger.kernel.org --- include/linux/skbuff.h | 7 +++++-- net/core/skbuff.c | 1 + net/ipv4/ip_output.c | 2 +- net/ipv4/tcp.c | 4 ++-- 4 files changed, 9 insertions(+), 5 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index df2b93f..dc92cf9 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1960,13 +1960,16 @@ static inline int skb_add_data(struct sk_buff *= skb, } =20 static inline int skb_can_coalesce(struct sk_buff *skb, int i, - const struct page *page, int off) + const struct page *page, + const struct skb_frag_destructor *destroy, + int off) { if (i) { const struct skb_frag_struct *frag =3D &skb_shinfo(skb)->frags[i - 1= ]; =20 return page =3D=3D skb_frag_page(frag) && - off =3D=3D frag->page_offset + skb_frag_size(frag); + off =3D=3D frag->page_offset + skb_frag_size(frag) && + frag->page.destructor =3D=3D destroy; } return 0; } diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 766b760..1f7dd9c 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2327,6 +2327,7 @@ int skb_shift(struct sk_buff *tgt, struct sk_buff= *skb, int shiftlen) */ if (!to || !skb_can_coalesce(tgt, to, skb_frag_page(fragfrom), + fragfrom->page.destructor, fragfrom->page_offset)) { merge =3D -1; } else { diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index ff302bd..9e4eca6 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -1243,7 +1243,7 @@ ssize_t ip_append_page(struct sock *sk, struct fl= owi4 *fl4, struct page *page, i =3D skb_shinfo(skb)->nr_frags; if (len > size) len =3D size; - if (skb_can_coalesce(skb, i, page, offset)) { + if (skb_can_coalesce(skb, i, page, NULL, offset)) { skb_frag_size_add(&skb_shinfo(skb)->frags[i-1], len); } else if (i < MAX_SKB_FRAGS) { get_page(page); diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 9bcdec3..a928aec 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -802,7 +802,7 @@ new_segment: copy =3D size; =20 i =3D skb_shinfo(skb)->nr_frags; - can_coalesce =3D skb_can_coalesce(skb, i, page, offset); + can_coalesce =3D skb_can_coalesce(skb, i, page, NULL, offset); if (!can_coalesce && i >=3D MAX_SKB_FRAGS) { tcp_mark_push(tp, skb); goto new_segment; @@ -1011,7 +1011,7 @@ new_segment: =20 off =3D sk->sk_sndmsg_off; =20 - if (skb_can_coalesce(skb, i, page, off) && + if (skb_can_coalesce(skb, i, page, NULL, off) && off !=3D PAGE_SIZE) { /* We can extend the last page * fragment. */ --=20 1.7.2.5