From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: [PATCH v2 2/2] virtio-net: make all RX paths handle erors consistently Date: Thu, 28 Nov 2013 13:30:59 +0200 Message-ID: <1385638044-27467-2-git-send-email-mst@redhat.com> References: <1385638044-27467-1-git-send-email-mst@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, virtualization@lists.linux-foundation.org To: linux-kernel@vger.kernel.org Return-path: Content-Disposition: inline In-Reply-To: <1385638044-27467-1-git-send-email-mst@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: netdev.vger.kernel.org receive mergeable now handles errors internally. Do same for big and small packet paths, otherwise the logic is too hard to follow. Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang --- I don't see a bug in current code but I think it's still a good idea to queue this in 3.13, for consistency. drivers/net/virtio_net.c | 54 +++++++++++++++++++++++++++++++++--------------- 1 file changed, 37 insertions(+), 17 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 5408de6..4b01946 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -299,6 +299,35 @@ static struct sk_buff *page_to_skb(struct receive_queue *rq, return skb; } +static struct sk_buff *receive_small(void *buf, unsigned int len) +{ + struct sk_buff * skb = buf; + + len -= sizeof(struct virtio_net_hdr); + skb_trim(skb, len); + + return skb; +} + +static struct sk_buff *receive_big(struct net_device *dev, + struct receive_queue *rq, + void *buf, + unsigned int len) +{ + struct page *page = buf; + struct sk_buff *skb = page_to_skb(rq, page, 0, len, PAGE_SIZE); + + if (unlikely(!skb)) + goto err; + + return skb; + +err: + dev->stats.rx_dropped++; + give_pages(rq, page); + return NULL; +} + static struct sk_buff *receive_mergeable(struct net_device *dev, struct receive_queue *rq, void *buf, @@ -392,7 +421,6 @@ static void receive_buf(struct receive_queue *rq, void *buf, unsigned int len) struct net_device *dev = vi->dev; struct virtnet_stats *stats = this_cpu_ptr(vi->stats); struct sk_buff *skb; - struct page *page; struct skb_vnet_hdr *hdr; if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) { @@ -407,23 +435,15 @@ static void receive_buf(struct receive_queue *rq, void *buf, unsigned int len) return; } - if (!vi->mergeable_rx_bufs && !vi->big_packets) { - skb = buf; - len -= sizeof(struct virtio_net_hdr); - skb_trim(skb, len); - } else if (vi->mergeable_rx_bufs) { + if (vi->mergeable_rx_bufs) skb = receive_mergeable(dev, rq, buf, len); - if (unlikely(!skb)) - return; - } else { - page = buf; - skb = page_to_skb(rq, page, 0, len, PAGE_SIZE); - if (unlikely(!skb)) { - dev->stats.rx_dropped++; - give_pages(rq, page); - return; - } - } + else if (vi->big_packets) + skb = receive_big(dev, rq, buf, len); + else + skb = receive_small(buf, len); + + if (unlikely(!skb)) + return; hdr = skb_vnet_hdr(skb); -- MST