From patchwork Tue Aug 6 09:45:08 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 264967 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 [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 4E87C2C0084 for ; Tue, 6 Aug 2013 19:57:16 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755844Ab3HFJ4q (ORCPT ); Tue, 6 Aug 2013 05:56:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:4730 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755901Ab3HFJ4h (ORCPT ); Tue, 6 Aug 2013 05:56:37 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r769ua0e026673 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 6 Aug 2013 05:56:36 -0400 Received: from amd-6168-8-1.englab.nay.redhat.com (amd-6168-8-1.englab.nay.redhat.com [10.66.104.52]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id r769uIew020485; Tue, 6 Aug 2013 05:56:34 -0400 From: Jason Wang To: davem@davemloft.net, mst@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Jason Wang Subject: [net-next 6/6] net: use skb_copy_datagram_from_iovec() in zerocopy_sg_from_iovec() Date: Tue, 6 Aug 2013 17:45:08 +0800 Message-Id: <1375782308-10565-7-git-send-email-jasowang@redhat.com> In-Reply-To: <1375782308-10565-1-git-send-email-jasowang@redhat.com> References: <1375782308-10565-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Use skb_copy_datagram_from_iovec() to avoid code duplication and make it easy to be read. Also we can do the skipping inside the zero-copy loop. Signed-off-by: Jason Wang --- net/core/datagram.c | 37 ++++++++++--------------------------- 1 files changed, 10 insertions(+), 27 deletions(-) diff --git a/net/core/datagram.c b/net/core/datagram.c index badcd93..af814e7 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -591,48 +591,31 @@ int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, int offset, size_t count) { int len = iov_length(from, count) - offset; - int copy = skb_headlen(skb); - int size, offset1 = 0; + int copy = min_t(int, skb_headlen(skb), len); + int size; int i = 0; - /* Skip over from offset */ - while (count && (offset >= from->iov_len)) { - offset -= from->iov_len; - ++from; - --count; - } - /* copy up to skb headlen */ - while (count && (copy > 0)) { - size = min_t(unsigned int, copy, from->iov_len - offset); - if (copy_from_user(skb->data + offset1, from->iov_base + offset, - size)) - return -EFAULT; - if (copy > size) { - ++from; - --count; - offset = 0; - } else - offset += size; - copy -= size; - offset1 += size; - } + if (skb_copy_datagram_from_iovec(skb, 0, from, offset, copy)) + return -EFAULT; - if (len == offset1) + if (len == copy) return 0; + offset += copy; while (count--) { struct page *page[MAX_SKB_FRAGS]; int num_pages; unsigned long base; unsigned long truesize; - len = from->iov_len - offset; - if (!len) { - offset = 0; + /* Skip over from offset and copied */ + if (offset >= from->iov_len) { + offset -= from->iov_len; ++from; continue; } + len = from->iov_len - offset; base = (unsigned long)from->iov_base + offset; size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT; if (i + size > MAX_SKB_FRAGS)