From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Herbert Subject: [RFC net-next 1/6] net: Checksum functions to replace 8 bytes at a time Date: Wed, 3 Jun 2015 12:58:17 -0700 Message-ID: <1433361502-3478761-2-git-send-email-tom@herbertland.com> References: <1433361502-3478761-1-git-send-email-tom@herbertland.com> Mime-Version: 1.0 Content-Type: text/plain To: , , , , Return-path: Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:14311 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754785AbbFCT6o (ORCPT ); Wed, 3 Jun 2015 15:58:44 -0400 Received: from pps.filterd (m0004077 [127.0.0.1]) by mx0b-00082601.pphosted.com (8.14.5/8.14.5) with SMTP id t53Jvwjk008260 for ; Wed, 3 Jun 2015 12:58:43 -0700 Received: from mail.thefacebook.com ([199.201.64.23]) by mx0b-00082601.pphosted.com with ESMTP id 1ut7h4r4gq-1 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT) for ; Wed, 03 Jun 2015 12:58:43 -0700 Received: from facebook.com (2401:db00:20:702e:face:0:23:0) by mx-out.facebook.com (10.212.236.89) with ESMTP id eeadcfa00a2a11e5861f0002c95209d8-e56dc280 for ; Wed, 03 Jun 2015 12:58:41 -0700 In-Reply-To: <1433361502-3478761-1-git-send-email-tom@herbertland.com> Sender: netdev-owner@vger.kernel.org List-ID: These are convenience functions for update a checksum in ILA where we are overwriting the locator (first eight bytes of an ILA IPv6 address). Signed-off-by: Tom Herbert --- include/net/checksum.h | 3 +++ net/core/utils.c | 19 +++++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/include/net/checksum.h b/include/net/checksum.h index 2d1d73c..af76b8e 100644 --- a/include/net/checksum.h +++ b/include/net/checksum.h @@ -141,6 +141,9 @@ static inline void csum_replace2(__sum16 *sum, __be16 old, __be16 new) struct sk_buff; void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb, __be32 from, __be32 to, int pseudohdr); +void inet_proto_csum_replace8(__sum16 *sum, struct sk_buff *skb, + const __be32 *from, const __be32 *to, + int pseudohdr); void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb, const __be32 *from, const __be32 *to, int pseudohdr); diff --git a/net/core/utils.c b/net/core/utils.c index a7732a0..79d1067 100644 --- a/net/core/utils.c +++ b/net/core/utils.c @@ -336,6 +336,25 @@ void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb, } EXPORT_SYMBOL(inet_proto_csum_replace16); +void inet_proto_csum_replace8(__sum16 *sum, struct sk_buff *skb, + const __be32 *from, const __be32 *to, + int pseudohdr) +{ + __be32 diff[] = { + ~from[0], ~from[1], to[0], to[1], + }; + if (skb->ip_summed != CHECKSUM_PARTIAL) { + *sum = csum_fold(csum_partial(diff, sizeof(diff), + ~csum_unfold(*sum))); + if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr) + skb->csum = ~csum_partial(diff, sizeof(diff), + ~skb->csum); + } else if (pseudohdr) + *sum = ~csum_fold(csum_partial(diff, sizeof(diff), + csum_unfold(*sum))); +} +EXPORT_SYMBOL(inet_proto_csum_replace8); + struct __net_random_once_work { struct work_struct work; struct static_key *key; -- 1.8.1