From mboxrd@z Thu Jan 1 00:00:00 1970 From: 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> References: <1375782308-10565-1-git-send-email-jasowang@redhat.com> Cc: Jason Wang To: davem@davemloft.net, mst@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: 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 In-Reply-To: <1375782308-10565-1-git-send-email-jasowang@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: 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) -- 1.7.1