From patchwork Sat Dec 13 01:35:23 2008 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herbert Xu X-Patchwork-Id: 13802 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id AC8C7DE153 for ; Sat, 13 Dec 2008 12:35:42 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753952AbYLMBfd (ORCPT ); Fri, 12 Dec 2008 20:35:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753911AbYLMBfc (ORCPT ); Fri, 12 Dec 2008 20:35:32 -0500 Received: from rhun.apana.org.au ([64.62.148.172]:53841 "EHLO arnor.apana.org.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753717AbYLMBf3 (ORCPT ); Fri, 12 Dec 2008 20:35:29 -0500 Received: from gondolin.me.apana.org.au ([192.168.0.6]) by arnor.apana.org.au with esmtp (Exim 4.63 #1 (Debian)) id 1LBJPg-00054W-04; Sat, 13 Dec 2008 12:35:25 +1100 Received: from herbert by gondolin.me.apana.org.au with local (Exim 4.69) (envelope-from ) id 1LBJPf-0003Yr-H2; Sat, 13 Dec 2008 12:35:23 +1100 Subject: [PATCH 5/8] net: Add skb_gro_receive References: <20081213013420.GA13549@gondor.apana.org.au> To: "David S. Miller" , netdev@vger.kernel.org, Evgeniy Polyakov , Ben Hutchings Message-Id: From: Herbert Xu Date: Sat, 13 Dec 2008 12:35:23 +1100 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org net: Add skb_gro_receive This patch adds the helper skb_gro_receive to merge packets for GRO. The current method is to allocate a new header skb and then chain the original packets to its frag_list. This is done to make it easier to integrate into the existing GSO framework. In future as GSO is moved into the drivers, we can undo this and simply chain the original packets together. Signed-off-by: Herbert Xu --- include/linux/skbuff.h | 2 + net/core/skbuff.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 59 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 2725f4e..2bdb539 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1649,6 +1649,8 @@ extern void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len); extern struct sk_buff *skb_segment(struct sk_buff *skb, int features); +extern int skb_gro_receive(struct sk_buff **head, + struct sk_buff *skb); static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, int len, void *buffer) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index cf05a8c..8ea648e 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2439,6 +2439,63 @@ err: EXPORT_SYMBOL_GPL(skb_segment); +int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) +{ + struct sk_buff *p = *head; + struct sk_buff *nskb; + unsigned int headroom; + unsigned int hlen; + + if (skb_shinfo(p)->frag_list) + goto merge; + + headroom = skb_headroom(p); + nskb = netdev_alloc_skb(p->dev, headroom); + if (unlikely(!nskb)) + return -ENOMEM; + + __copy_skb_header(nskb, p); + nskb->mac_len = p->mac_len; + + skb_reserve(nskb, headroom); + + hlen = p->data - skb_mac_header(p); + skb_set_mac_header(nskb, -hlen); + skb_set_network_header(nskb, skb_network_offset(p)); + skb_set_transport_header(nskb, skb_transport_offset(p)); + + memcpy(skb_mac_header(nskb), skb_mac_header(p), hlen); + + *NAPI_GRO_CB(nskb) = *NAPI_GRO_CB(p); + skb_shinfo(nskb)->frag_list = p; + skb_header_release(p); + nskb->prev = p; + + nskb->data_len += p->len; + nskb->truesize += p->len; + nskb->len += p->len; + + *head = nskb; + nskb->next = p->next; + p->next = NULL; + + p = nskb; + +merge: + NAPI_GRO_CB(p)->count++; + p->prev->next = skb; + p->prev = skb; + skb_header_release(skb); + + p->data_len += skb->len; + p->truesize += skb->len; + p->len += skb->len; + + NAPI_GRO_CB(skb)->same_flow = 1; + return 0; +} +EXPORT_SYMBOL_GPL(skb_gro_receive); + void __init skb_init(void) { skbuff_head_cache = kmem_cache_create("skbuff_head_cache",