From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Duyck Subject: [net-next PATCH 06/10] gre: Use GSO flags to determine csum need instead of GRE flags Date: Fri, 05 Feb 2016 15:28:01 -0800 Message-ID: <20160205232801.18529.33991.stgit@localhost.localdomain> References: <20160205232109.18529.99816.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: ecree@solarflare.com, tom@herbertland.com, davem@davemloft.net To: netdev@vger.kernel.org, alexander.duyck@gmail.com Return-path: Received: from mail-pf0-f173.google.com ([209.85.192.173]:33830 "EHLO mail-pf0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750735AbcBEX2E (ORCPT ); Fri, 5 Feb 2016 18:28:04 -0500 Received: by mail-pf0-f173.google.com with SMTP id o185so76292456pfb.1 for ; Fri, 05 Feb 2016 15:28:03 -0800 (PST) In-Reply-To: <20160205232109.18529.99816.stgit@localhost.localdomain> Sender: netdev-owner@vger.kernel.org List-ID: This patch updates the gre checksum path to follow something much closer to the UDP checksum path. By doing this we can avoid needing to do as much header inspection and can just make use of the fields we were already reading in the sk_buff structure. Signed-off-by: Alexander Duyck --- net/ipv4/gre_offload.c | 64 +++++++++++++++++++++++------------------------- 1 file changed, 30 insertions(+), 34 deletions(-) diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c index 35a8dd35ed4e..c15441b5ff61 100644 --- a/net/ipv4/gre_offload.c +++ b/net/ipv4/gre_offload.c @@ -18,14 +18,14 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb, netdev_features_t features) { + int tnl_hlen = skb_inner_mac_header(skb) - skb_transport_header(skb); struct sk_buff *segs = ERR_PTR(-EINVAL); - int ghl; struct gre_base_hdr *greh; u16 mac_offset = skb->mac_header; - int mac_len = skb->mac_len; __be16 protocol = skb->protocol; - int tnl_hlen; - bool csum; + u16 mac_len = skb->mac_len; + int gre_offset, outer_hlen; + bool need_csum; if (unlikely(skb_shinfo(skb)->gso_type & ~(SKB_GSO_TCPV4 | @@ -42,64 +42,60 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb, if (!skb->encapsulation) goto out; - if (unlikely(!pskb_may_pull(skb, sizeof(*greh)))) + if (unlikely(tnl_hlen < sizeof(struct gre_base_hdr))) goto out; - greh = (struct gre_base_hdr *)skb_transport_header(skb); - - ghl = skb_inner_mac_header(skb) - skb_transport_header(skb); - if (unlikely(ghl < sizeof(*greh))) + if (unlikely(!pskb_may_pull(skb, tnl_hlen))) goto out; - csum = !!(greh->flags & GRE_CSUM); - if (csum) - skb->encap_hdr_csum = 1; + greh = (struct gre_base_hdr *)skb_transport_header(skb); /* setup inner skb. */ skb->protocol = greh->protocol; skb->encapsulation = 0; - - if (unlikely(!pskb_may_pull(skb, ghl))) - goto out; - - __skb_pull(skb, ghl); + __skb_pull(skb, tnl_hlen); skb_reset_mac_header(skb); skb_set_network_header(skb, skb_inner_network_offset(skb)); skb->mac_len = skb_inner_network_offset(skb); + need_csum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_GRE_CSUM); + skb->encap_hdr_csum = need_csum; + features &= skb->dev->hw_enc_features; /* segment inner packet. */ segs = skb_mac_gso_segment(skb, features); if (IS_ERR_OR_NULL(segs)) { - skb_gso_error_unwind(skb, protocol, ghl, mac_offset, mac_len); + skb_gso_error_unwind(skb, protocol, tnl_hlen, mac_offset, + mac_len); goto out; } + outer_hlen = skb_tnl_header_len(skb); + gre_offset = outer_hlen - tnl_hlen; skb = segs; - tnl_hlen = skb_tnl_header_len(skb); do { - __skb_push(skb, ghl); - if (csum) { - __be32 *pcsum; - - skb_reset_transport_header(skb); - - greh = (struct gre_base_hdr *) - skb_transport_header(skb); - pcsum = (__be32 *)(greh + 1); - *pcsum = 0; - *(__sum16 *)pcsum = gso_make_checksum(skb, 0); - } - __skb_push(skb, tnl_hlen - ghl); + __be32 *pcsum; skb_reset_inner_headers(skb); skb->encapsulation = 1; - skb_reset_mac_header(skb); - skb_set_network_header(skb, mac_len); skb->mac_len = mac_len; skb->protocol = protocol; + + __skb_push(skb, outer_hlen); + skb_reset_mac_header(skb); + skb_set_network_header(skb, mac_len); + skb_set_transport_header(skb, gre_offset); + + if (!need_csum) + continue; + + greh = (struct gre_base_hdr *)skb_transport_header(skb); + pcsum = (__be32 *)(greh + 1); + + *pcsum = 0; + *(__sum16 *)pcsum = gso_make_checksum(skb, 0); } while ((skb = skb->next)); out: return segs;