2007-10-22 03:03:37 +02:00
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/* A simple network driver using virtio.
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*
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* Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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//#define DEBUG
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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2008-04-18 05:21:42 +02:00
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#include <linux/ethtool.h>
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2007-10-22 03:03:37 +02:00
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#include <linux/module.h>
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#include <linux/virtio.h>
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#include <linux/virtio_net.h>
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#include <linux/scatterlist.h>
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2007-12-16 14:19:43 +01:00
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static int napi_weight = 128;
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module_param(napi_weight, int, 0444);
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2008-02-05 05:50:02 +01:00
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static int csum = 1, gso = 1;
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module_param(csum, bool, 0444);
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module_param(gso, bool, 0444);
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2007-10-22 03:03:37 +02:00
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/* FIXME: MTU in config. */
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#define MAX_PACKET_LEN (ETH_HLEN+ETH_DATA_LEN)
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2008-11-17 07:41:34 +01:00
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#define GOOD_COPY_LEN 128
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2007-10-22 03:03:37 +02:00
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struct virtnet_info
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{
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struct virtio_device *vdev;
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struct virtqueue *rvq, *svq;
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struct net_device *dev;
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struct napi_struct napi;
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2008-05-03 04:50:46 +02:00
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/* The skb we couldn't send because buffers were full. */
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struct sk_buff *last_xmit_skb;
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2008-06-08 12:51:55 +02:00
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/* If we need to free in a timer, this is it. */
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2008-06-08 12:50:56 +02:00
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struct timer_list xmit_free_timer;
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2007-10-22 03:03:37 +02:00
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/* Number of input buffers, and max we've ever had. */
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unsigned int num, max;
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2008-05-26 09:48:13 +02:00
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/* For cleaning up after transmission. */
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struct tasklet_struct tasklet;
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2008-06-08 12:51:55 +02:00
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bool free_in_tasklet;
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2008-05-26 09:48:13 +02:00
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2008-04-18 05:24:27 +02:00
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/* I like... big packets and I cannot lie! */
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bool big_packets;
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2008-11-17 07:41:34 +01:00
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/* Host will merge rx buffers for big packets (shake it! shake it!) */
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bool mergeable_rx_bufs;
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2007-10-22 03:03:37 +02:00
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/* Receive & send queues. */
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struct sk_buff_head recv;
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struct sk_buff_head send;
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2008-07-25 19:06:01 +02:00
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/* Chain pages by the private ptr. */
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struct page *pages;
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2007-10-22 03:03:37 +02:00
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};
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2008-11-17 07:41:34 +01:00
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static inline void *skb_vnet_hdr(struct sk_buff *skb)
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2007-10-22 03:03:37 +02:00
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{
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return (struct virtio_net_hdr *)skb->cb;
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}
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2008-07-25 19:06:01 +02:00
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static void give_a_page(struct virtnet_info *vi, struct page *page)
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{
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page->private = (unsigned long)vi->pages;
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vi->pages = page;
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}
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2008-11-17 07:39:18 +01:00
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static void trim_pages(struct virtnet_info *vi, struct sk_buff *skb)
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{
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unsigned int i;
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for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
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give_a_page(vi, skb_shinfo(skb)->frags[i].page);
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skb_shinfo(skb)->nr_frags = 0;
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skb->data_len = 0;
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}
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2008-07-25 19:06:01 +02:00
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static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
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{
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struct page *p = vi->pages;
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if (p)
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vi->pages = (struct page *)p->private;
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else
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p = alloc_page(gfp_mask);
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return p;
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}
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2008-02-05 05:50:07 +01:00
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static void skb_xmit_done(struct virtqueue *svq)
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2007-10-22 03:03:37 +02:00
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{
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2008-02-05 05:50:07 +01:00
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struct virtnet_info *vi = svq->vdev->priv;
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2007-10-22 03:03:37 +02:00
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2008-02-05 05:50:07 +01:00
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/* Suppress further interrupts. */
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svq->vq_ops->disable_cb(svq);
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2008-05-26 09:48:13 +02:00
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2008-06-08 12:51:55 +02:00
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/* We were probably waiting for more output buffers. */
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2007-10-22 03:03:37 +02:00
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netif_wake_queue(vi->dev);
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2008-05-26 09:48:13 +02:00
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/* Make sure we re-xmit last_xmit_skb: if there are no more packets
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* queued, start_xmit won't be called. */
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tasklet_schedule(&vi->tasklet);
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2007-10-22 03:03:37 +02:00
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}
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static void receive_skb(struct net_device *dev, struct sk_buff *skb,
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unsigned len)
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{
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2008-11-17 07:41:34 +01:00
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struct virtnet_info *vi = netdev_priv(dev);
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2007-10-22 03:03:37 +02:00
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struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
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2008-04-18 05:24:27 +02:00
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int err;
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2008-11-17 07:41:34 +01:00
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int i;
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2007-10-22 03:03:37 +02:00
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if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
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pr_debug("%s: short packet %i\n", dev->name, len);
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dev->stats.rx_length_errors++;
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goto drop;
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}
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2008-06-08 12:49:00 +02:00
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2008-11-17 07:41:34 +01:00
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if (vi->mergeable_rx_bufs) {
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struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
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unsigned int copy;
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char *p = page_address(skb_shinfo(skb)->frags[0].page);
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2008-07-25 19:06:01 +02:00
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2008-11-17 07:41:34 +01:00
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if (len > PAGE_SIZE)
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len = PAGE_SIZE;
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len -= sizeof(struct virtio_net_hdr_mrg_rxbuf);
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memcpy(hdr, p, sizeof(*mhdr));
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p += sizeof(*mhdr);
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copy = len;
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if (copy > skb_tailroom(skb))
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copy = skb_tailroom(skb);
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memcpy(skb_put(skb, copy), p, copy);
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len -= copy;
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if (!len) {
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give_a_page(vi, skb_shinfo(skb)->frags[0].page);
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skb_shinfo(skb)->nr_frags--;
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} else {
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skb_shinfo(skb)->frags[0].page_offset +=
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sizeof(*mhdr) + copy;
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skb_shinfo(skb)->frags[0].size = len;
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skb->data_len += len;
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skb->len += len;
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}
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while (--mhdr->num_buffers) {
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struct sk_buff *nskb;
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i = skb_shinfo(skb)->nr_frags;
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if (i >= MAX_SKB_FRAGS) {
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pr_debug("%s: packet too long %d\n", dev->name,
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len);
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dev->stats.rx_length_errors++;
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goto drop;
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}
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nskb = vi->rvq->vq_ops->get_buf(vi->rvq, &len);
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if (!nskb) {
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pr_debug("%s: rx error: %d buffers missing\n",
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dev->name, mhdr->num_buffers);
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dev->stats.rx_length_errors++;
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goto drop;
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}
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__skb_unlink(nskb, &vi->recv);
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vi->num--;
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skb_shinfo(skb)->frags[i] = skb_shinfo(nskb)->frags[0];
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skb_shinfo(nskb)->nr_frags = 0;
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kfree_skb(nskb);
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if (len > PAGE_SIZE)
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len = PAGE_SIZE;
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skb_shinfo(skb)->frags[i].size = len;
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skb_shinfo(skb)->nr_frags++;
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skb->data_len += len;
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skb->len += len;
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}
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} else {
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len -= sizeof(struct virtio_net_hdr);
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if (len <= MAX_PACKET_LEN)
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trim_pages(vi, skb);
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err = pskb_trim(skb, len);
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if (err) {
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pr_debug("%s: pskb_trim failed %i %d\n", dev->name,
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len, err);
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dev->stats.rx_dropped++;
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goto drop;
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}
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2008-04-18 05:24:27 +02:00
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}
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2008-11-17 07:41:34 +01:00
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2008-04-18 05:24:27 +02:00
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skb->truesize += skb->data_len;
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2007-10-22 03:03:37 +02:00
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dev->stats.rx_bytes += skb->len;
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dev->stats.rx_packets++;
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if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
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pr_debug("Needs csum!\n");
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2008-02-05 05:49:54 +01:00
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if (!skb_partial_csum_set(skb,hdr->csum_start,hdr->csum_offset))
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2007-10-22 03:03:37 +02:00
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goto frame_err;
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}
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2008-06-08 12:49:00 +02:00
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skb->protocol = eth_type_trans(skb, dev);
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pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
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ntohs(skb->protocol), skb->len, skb->pkt_type);
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2007-10-22 03:03:37 +02:00
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if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
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pr_debug("GSO!\n");
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2008-02-05 05:50:02 +01:00
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switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
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2007-10-22 03:03:37 +02:00
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case VIRTIO_NET_HDR_GSO_TCPV4:
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skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
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break;
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case VIRTIO_NET_HDR_GSO_UDP:
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skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
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break;
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case VIRTIO_NET_HDR_GSO_TCPV6:
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skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
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break;
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default:
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if (net_ratelimit())
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printk(KERN_WARNING "%s: bad gso type %u.\n",
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dev->name, hdr->gso_type);
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goto frame_err;
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}
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2008-02-05 05:50:02 +01:00
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if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
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skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
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2007-10-22 03:03:37 +02:00
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skb_shinfo(skb)->gso_size = hdr->gso_size;
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if (skb_shinfo(skb)->gso_size == 0) {
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if (net_ratelimit())
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printk(KERN_WARNING "%s: zero gso size.\n",
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dev->name);
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goto frame_err;
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}
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/* Header must be checked, and gso_segs computed. */
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skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
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skb_shinfo(skb)->gso_segs = 0;
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}
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netif_receive_skb(skb);
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return;
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frame_err:
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dev->stats.rx_frame_errors++;
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drop:
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dev_kfree_skb(skb);
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}
|
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|
|
|
2008-11-17 07:41:34 +01:00
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static void try_fill_recv_maxbufs(struct virtnet_info *vi)
|
2007-10-22 03:03:37 +02:00
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|
|
{
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struct sk_buff *skb;
|
2008-05-03 04:50:45 +02:00
|
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struct scatterlist sg[2+MAX_SKB_FRAGS];
|
2008-04-18 05:24:27 +02:00
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int num, err, i;
|
2007-10-22 03:03:37 +02:00
|
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|
|
2008-05-03 04:50:45 +02:00
|
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sg_init_table(sg, 2+MAX_SKB_FRAGS);
|
2007-10-22 03:03:37 +02:00
|
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|
for (;;) {
|
2008-11-17 07:41:34 +01:00
|
|
|
struct virtio_net_hdr *hdr;
|
|
|
|
|
2007-10-22 03:03:37 +02:00
|
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skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
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|
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if (unlikely(!skb))
|
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break;
|
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|
|
|
|
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|
skb_put(skb, MAX_PACKET_LEN);
|
2008-11-17 07:41:34 +01:00
|
|
|
|
|
|
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hdr = skb_vnet_hdr(skb);
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|
|
sg_init_one(sg, hdr, sizeof(*hdr));
|
2008-04-18 05:24:27 +02:00
|
|
|
|
|
|
|
if (vi->big_packets) {
|
|
|
|
for (i = 0; i < MAX_SKB_FRAGS; i++) {
|
|
|
|
skb_frag_t *f = &skb_shinfo(skb)->frags[i];
|
2008-07-25 19:06:01 +02:00
|
|
|
f->page = get_a_page(vi, GFP_ATOMIC);
|
2008-04-18 05:24:27 +02:00
|
|
|
if (!f->page)
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|
|
break;
|
|
|
|
|
|
|
|
f->page_offset = 0;
|
|
|
|
f->size = PAGE_SIZE;
|
|
|
|
|
|
|
|
skb->data_len += PAGE_SIZE;
|
|
|
|
skb->len += PAGE_SIZE;
|
|
|
|
|
|
|
|
skb_shinfo(skb)->nr_frags++;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2007-10-22 03:03:37 +02:00
|
|
|
num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
|
|
|
|
skb_queue_head(&vi->recv, skb);
|
|
|
|
|
|
|
|
err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
|
|
|
|
if (err) {
|
|
|
|
skb_unlink(skb, &vi->recv);
|
2008-11-17 07:39:18 +01:00
|
|
|
trim_pages(vi, skb);
|
2007-10-22 03:03:37 +02:00
|
|
|
kfree_skb(skb);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
vi->num++;
|
|
|
|
}
|
|
|
|
if (unlikely(vi->num > vi->max))
|
|
|
|
vi->max = vi->num;
|
|
|
|
vi->rvq->vq_ops->kick(vi->rvq);
|
|
|
|
}
|
|
|
|
|
2008-11-17 07:41:34 +01:00
|
|
|
static void try_fill_recv(struct virtnet_info *vi)
|
|
|
|
{
|
|
|
|
struct sk_buff *skb;
|
|
|
|
struct scatterlist sg[1];
|
|
|
|
int err;
|
|
|
|
|
|
|
|
if (!vi->mergeable_rx_bufs) {
|
|
|
|
try_fill_recv_maxbufs(vi);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
for (;;) {
|
|
|
|
skb_frag_t *f;
|
|
|
|
|
|
|
|
skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN);
|
|
|
|
if (unlikely(!skb))
|
|
|
|
break;
|
|
|
|
|
|
|
|
skb_reserve(skb, NET_IP_ALIGN);
|
|
|
|
|
|
|
|
f = &skb_shinfo(skb)->frags[0];
|
|
|
|
f->page = get_a_page(vi, GFP_ATOMIC);
|
|
|
|
if (!f->page) {
|
|
|
|
kfree_skb(skb);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
f->page_offset = 0;
|
|
|
|
f->size = PAGE_SIZE;
|
|
|
|
|
|
|
|
skb_shinfo(skb)->nr_frags++;
|
|
|
|
|
|
|
|
sg_init_one(sg, page_address(f->page), PAGE_SIZE);
|
|
|
|
skb_queue_head(&vi->recv, skb);
|
|
|
|
|
|
|
|
err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb);
|
|
|
|
if (err) {
|
|
|
|
skb_unlink(skb, &vi->recv);
|
|
|
|
kfree_skb(skb);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
vi->num++;
|
|
|
|
}
|
|
|
|
if (unlikely(vi->num > vi->max))
|
|
|
|
vi->max = vi->num;
|
|
|
|
vi->rvq->vq_ops->kick(vi->rvq);
|
|
|
|
}
|
|
|
|
|
2008-02-05 05:49:57 +01:00
|
|
|
static void skb_recv_done(struct virtqueue *rvq)
|
2007-10-22 03:03:37 +02:00
|
|
|
{
|
|
|
|
struct virtnet_info *vi = rvq->vdev->priv;
|
2008-02-05 05:49:57 +01:00
|
|
|
/* Schedule NAPI, Suppress further interrupts if successful. */
|
|
|
|
if (netif_rx_schedule_prep(vi->dev, &vi->napi)) {
|
|
|
|
rvq->vq_ops->disable_cb(rvq);
|
|
|
|
__netif_rx_schedule(vi->dev, &vi->napi);
|
|
|
|
}
|
2007-10-22 03:03:37 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
static int virtnet_poll(struct napi_struct *napi, int budget)
|
|
|
|
{
|
|
|
|
struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
|
|
|
|
struct sk_buff *skb = NULL;
|
|
|
|
unsigned int len, received = 0;
|
|
|
|
|
|
|
|
again:
|
|
|
|
while (received < budget &&
|
|
|
|
(skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
|
|
|
|
__skb_unlink(skb, &vi->recv);
|
|
|
|
receive_skb(vi->dev, skb, len);
|
|
|
|
vi->num--;
|
|
|
|
received++;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* FIXME: If we oom and completely run out of inbufs, we need
|
|
|
|
* to start a timer trying to fill more. */
|
|
|
|
if (vi->num < vi->max / 2)
|
|
|
|
try_fill_recv(vi);
|
|
|
|
|
2007-11-19 17:20:43 +01:00
|
|
|
/* Out of packets? */
|
|
|
|
if (received < budget) {
|
2007-10-22 03:03:37 +02:00
|
|
|
netif_rx_complete(vi->dev, napi);
|
2008-02-05 05:49:57 +01:00
|
|
|
if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq))
|
virtio: fix race in enable_cb
There is a race in virtio_net, dealing with disabling/enabling the callback.
I saw the following oops:
kernel BUG at /space/kvm/drivers/virtio/virtio_ring.c:218!
illegal operation: 0001 [#1] SMP
Modules linked in: sunrpc dm_mod
CPU: 2 Not tainted 2.6.25-rc1zlive-host-10623-gd358142-dirty #99
Process swapper (pid: 0, task: 000000000f85a610, ksp: 000000000f873c60)
Krnl PSW : 0404300180000000 00000000002b81a6 (vring_disable_cb+0x16/0x20)
R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:3 PM:0 EA:3
Krnl GPRS: 0000000000000001 0000000000000001 0000000010005800 0000000000000001
000000000f3a0900 000000000f85a610 0000000000000000 0000000000000000
0000000000000000 000000000f870000 0000000000000000 0000000000001237
000000000f3a0920 000000000010ff74 00000000002846f6 000000000fa0bcd8
Krnl Code: 00000000002b819a: a7110001 tmll %r1,1
00000000002b819e: a7840004 brc 8,2b81a6
00000000002b81a2: a7f40001 brc 15,2b81a4
>00000000002b81a6: a51b0001 oill %r1,1
00000000002b81aa: 40102000 sth %r1,0(%r2)
00000000002b81ae: 07fe bcr 15,%r14
00000000002b81b0: eb7ff0380024 stmg %r7,%r15,56(%r15)
00000000002b81b6: a7f13e00 tmll %r15,15872
Call Trace:
([<000000000fa0bcd0>] 0xfa0bcd0)
[<00000000002b8350>] vring_interrupt+0x5c/0x6c
[<000000000010ab08>] do_extint+0xb8/0xf0
[<0000000000110716>] ext_no_vtime+0x16/0x1a
[<0000000000107e72>] cpu_idle+0x1c2/0x1e0
The problem can be triggered with a high amount of host->guest traffic.
I think its the following race:
poll says netif_rx_complete
poll calls enable_cb
enable_cb opens the interrupt mask
a new packet comes, an interrupt is triggered----\
enable_cb sees that there is more work |
enable_cb disables the interrupt |
. V
. interrupt is delivered
. skb_recv_done does atomic napi test, ok
some waiting disable_cb is called->check fails->bang!
.
poll would do napi check
poll would do disable_cb
The fix is to let enable_cb not disable the interrupt again, but expect the
caller to do the cleanup if it returns false. In that case, the interrupt is
only disabled, if the napi test_set_bit was successful.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cleaned up doco)
2008-03-14 14:17:05 +01:00
|
|
|
&& napi_schedule_prep(napi)) {
|
|
|
|
vi->rvq->vq_ops->disable_cb(vi->rvq);
|
|
|
|
__netif_rx_schedule(vi->dev, napi);
|
2007-10-22 03:03:37 +02:00
|
|
|
goto again;
|
virtio: fix race in enable_cb
There is a race in virtio_net, dealing with disabling/enabling the callback.
I saw the following oops:
kernel BUG at /space/kvm/drivers/virtio/virtio_ring.c:218!
illegal operation: 0001 [#1] SMP
Modules linked in: sunrpc dm_mod
CPU: 2 Not tainted 2.6.25-rc1zlive-host-10623-gd358142-dirty #99
Process swapper (pid: 0, task: 000000000f85a610, ksp: 000000000f873c60)
Krnl PSW : 0404300180000000 00000000002b81a6 (vring_disable_cb+0x16/0x20)
R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:3 PM:0 EA:3
Krnl GPRS: 0000000000000001 0000000000000001 0000000010005800 0000000000000001
000000000f3a0900 000000000f85a610 0000000000000000 0000000000000000
0000000000000000 000000000f870000 0000000000000000 0000000000001237
000000000f3a0920 000000000010ff74 00000000002846f6 000000000fa0bcd8
Krnl Code: 00000000002b819a: a7110001 tmll %r1,1
00000000002b819e: a7840004 brc 8,2b81a6
00000000002b81a2: a7f40001 brc 15,2b81a4
>00000000002b81a6: a51b0001 oill %r1,1
00000000002b81aa: 40102000 sth %r1,0(%r2)
00000000002b81ae: 07fe bcr 15,%r14
00000000002b81b0: eb7ff0380024 stmg %r7,%r15,56(%r15)
00000000002b81b6: a7f13e00 tmll %r15,15872
Call Trace:
([<000000000fa0bcd0>] 0xfa0bcd0)
[<00000000002b8350>] vring_interrupt+0x5c/0x6c
[<000000000010ab08>] do_extint+0xb8/0xf0
[<0000000000110716>] ext_no_vtime+0x16/0x1a
[<0000000000107e72>] cpu_idle+0x1c2/0x1e0
The problem can be triggered with a high amount of host->guest traffic.
I think its the following race:
poll says netif_rx_complete
poll calls enable_cb
enable_cb opens the interrupt mask
a new packet comes, an interrupt is triggered----\
enable_cb sees that there is more work |
enable_cb disables the interrupt |
. V
. interrupt is delivered
. skb_recv_done does atomic napi test, ok
some waiting disable_cb is called->check fails->bang!
.
poll would do napi check
poll would do disable_cb
The fix is to let enable_cb not disable the interrupt again, but expect the
caller to do the cleanup if it returns false. In that case, the interrupt is
only disabled, if the napi test_set_bit was successful.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cleaned up doco)
2008-03-14 14:17:05 +01:00
|
|
|
}
|
2007-10-22 03:03:37 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
return received;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void free_old_xmit_skbs(struct virtnet_info *vi)
|
|
|
|
{
|
|
|
|
struct sk_buff *skb;
|
|
|
|
unsigned int len;
|
|
|
|
|
|
|
|
while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
|
|
|
|
pr_debug("Sent skb %p\n", skb);
|
|
|
|
__skb_unlink(skb, &vi->send);
|
2008-05-03 04:50:43 +02:00
|
|
|
vi->dev->stats.tx_bytes += skb->len;
|
2007-10-22 03:03:37 +02:00
|
|
|
vi->dev->stats.tx_packets++;
|
|
|
|
kfree_skb(skb);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2008-06-08 12:51:55 +02:00
|
|
|
/* If the virtio transport doesn't always notify us when all in-flight packets
|
|
|
|
* are consumed, we fall back to using this function on a timer to free them. */
|
2008-06-08 12:50:56 +02:00
|
|
|
static void xmit_free(unsigned long data)
|
|
|
|
{
|
|
|
|
struct virtnet_info *vi = (void *)data;
|
|
|
|
|
|
|
|
netif_tx_lock(vi->dev);
|
|
|
|
|
|
|
|
free_old_xmit_skbs(vi);
|
|
|
|
|
|
|
|
if (!skb_queue_empty(&vi->send))
|
|
|
|
mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
|
|
|
|
|
|
|
|
netif_tx_unlock(vi->dev);
|
|
|
|
}
|
|
|
|
|
2008-05-03 04:50:46 +02:00
|
|
|
static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
|
2007-10-22 03:03:37 +02:00
|
|
|
{
|
2008-06-08 12:50:56 +02:00
|
|
|
int num, err;
|
2008-05-03 04:50:45 +02:00
|
|
|
struct scatterlist sg[2+MAX_SKB_FRAGS];
|
2008-11-17 07:41:34 +01:00
|
|
|
struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
|
|
|
|
struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
|
2007-10-22 03:03:37 +02:00
|
|
|
const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
|
|
|
|
|
2008-05-03 04:50:45 +02:00
|
|
|
sg_init_table(sg, 2+MAX_SKB_FRAGS);
|
2007-11-07 06:34:49 +01:00
|
|
|
|
2008-10-27 23:59:26 +01:00
|
|
|
pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
|
2007-10-22 03:03:37 +02:00
|
|
|
|
|
|
|
if (skb->ip_summed == CHECKSUM_PARTIAL) {
|
|
|
|
hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
|
|
|
|
hdr->csum_start = skb->csum_start - skb_headroom(skb);
|
|
|
|
hdr->csum_offset = skb->csum_offset;
|
|
|
|
} else {
|
|
|
|
hdr->flags = 0;
|
|
|
|
hdr->csum_offset = hdr->csum_start = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (skb_is_gso(skb)) {
|
2008-02-05 05:50:01 +01:00
|
|
|
hdr->hdr_len = skb_transport_header(skb) - skb->data;
|
2007-10-22 03:03:37 +02:00
|
|
|
hdr->gso_size = skb_shinfo(skb)->gso_size;
|
2008-02-05 05:50:02 +01:00
|
|
|
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
|
2007-10-22 03:03:37 +02:00
|
|
|
hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
|
|
|
|
else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
|
|
|
|
hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
|
|
|
|
else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
|
|
|
|
hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
|
|
|
|
else
|
|
|
|
BUG();
|
2008-02-05 05:50:02 +01:00
|
|
|
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
|
|
|
|
hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
|
2007-10-22 03:03:37 +02:00
|
|
|
} else {
|
|
|
|
hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
|
2008-02-05 05:50:01 +01:00
|
|
|
hdr->gso_size = hdr->hdr_len = 0;
|
2007-10-22 03:03:37 +02:00
|
|
|
}
|
|
|
|
|
2008-11-17 07:41:34 +01:00
|
|
|
mhdr->num_buffers = 0;
|
|
|
|
|
|
|
|
/* Encode metadata header at front. */
|
|
|
|
if (vi->mergeable_rx_bufs)
|
|
|
|
sg_init_one(sg, mhdr, sizeof(*mhdr));
|
|
|
|
else
|
|
|
|
sg_init_one(sg, hdr, sizeof(*hdr));
|
|
|
|
|
2007-10-22 03:03:37 +02:00
|
|
|
num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
|
2008-05-03 04:50:46 +02:00
|
|
|
|
2008-06-08 12:50:56 +02:00
|
|
|
err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
|
2008-06-08 12:51:55 +02:00
|
|
|
if (!err && !vi->free_in_tasklet)
|
2008-06-08 12:50:56 +02:00
|
|
|
mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
|
|
|
|
|
|
|
|
return err;
|
2008-05-03 04:50:46 +02:00
|
|
|
}
|
|
|
|
|
2008-05-26 09:48:13 +02:00
|
|
|
static void xmit_tasklet(unsigned long data)
|
|
|
|
{
|
|
|
|
struct virtnet_info *vi = (void *)data;
|
|
|
|
|
|
|
|
netif_tx_lock_bh(vi->dev);
|
|
|
|
if (vi->last_xmit_skb && xmit_skb(vi, vi->last_xmit_skb) == 0) {
|
|
|
|
vi->svq->vq_ops->kick(vi->svq);
|
|
|
|
vi->last_xmit_skb = NULL;
|
|
|
|
}
|
2008-06-08 12:51:55 +02:00
|
|
|
if (vi->free_in_tasklet)
|
|
|
|
free_old_xmit_skbs(vi);
|
2008-05-26 09:48:13 +02:00
|
|
|
netif_tx_unlock_bh(vi->dev);
|
|
|
|
}
|
|
|
|
|
2008-05-03 04:50:46 +02:00
|
|
|
static int start_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
|
|
{
|
|
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
2008-02-05 05:50:07 +01:00
|
|
|
|
|
|
|
again:
|
|
|
|
/* Free up any pending old buffers before queueing new ones. */
|
|
|
|
free_old_xmit_skbs(vi);
|
2008-05-03 04:50:46 +02:00
|
|
|
|
|
|
|
/* If we has a buffer left over from last time, send it now. */
|
virtio: fix virtio_net xmit of freed skb bug
On Mon, 2008-05-26 at 17:42 +1000, Rusty Russell wrote:
> If we fail to transmit a packet, we assume the queue is full and put
> the skb into last_xmit_skb. However, if more space frees up before we
> xmit it, we loop, and the result can be transmitting the same skb twice.
>
> Fix is simple: set skb to NULL if we've used it in some way, and check
> before sending.
...
> diff -r 564237b31993 drivers/net/virtio_net.c
> --- a/drivers/net/virtio_net.c Mon May 19 12:22:00 2008 +1000
> +++ b/drivers/net/virtio_net.c Mon May 19 12:24:58 2008 +1000
> @@ -287,21 +287,25 @@ again:
> free_old_xmit_skbs(vi);
>
> /* If we has a buffer left over from last time, send it now. */
> - if (vi->last_xmit_skb) {
> + if (unlikely(vi->last_xmit_skb)) {
> if (xmit_skb(vi, vi->last_xmit_skb) != 0) {
> /* Drop this skb: we only queue one. */
> vi->dev->stats.tx_dropped++;
> kfree_skb(skb);
> + skb = NULL;
> goto stop_queue;
> }
> vi->last_xmit_skb = NULL;
With this, may drop an skb and then later in the function discover that
we could have sent it after all. Poor wee skb :)
How about the incremental patch below?
Cheers,
Mark.
Subject: [PATCH] virtio_net: Delay dropping tx skbs
Currently we drop the skb in start_xmit() if we have a
queued buffer and fail to transmit it.
However, if we delay dropping it until we've stopped the
queue and enabled the tx notification callback, then there
is a chance space might become available for it.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-27 13:06:26 +02:00
|
|
|
if (unlikely(vi->last_xmit_skb) &&
|
|
|
|
xmit_skb(vi, vi->last_xmit_skb) != 0)
|
|
|
|
goto stop_queue;
|
|
|
|
|
|
|
|
vi->last_xmit_skb = NULL;
|
2008-02-05 05:50:07 +01:00
|
|
|
|
2008-05-03 04:50:46 +02:00
|
|
|
/* Put new one in send queue and do transmit */
|
2008-05-26 09:42:42 +02:00
|
|
|
if (likely(skb)) {
|
|
|
|
__skb_queue_head(&vi->send, skb);
|
|
|
|
if (xmit_skb(vi, skb) != 0) {
|
|
|
|
vi->last_xmit_skb = skb;
|
|
|
|
skb = NULL;
|
|
|
|
goto stop_queue;
|
|
|
|
}
|
2007-10-22 03:03:37 +02:00
|
|
|
}
|
2008-05-03 04:50:46 +02:00
|
|
|
done:
|
2007-10-22 03:03:37 +02:00
|
|
|
vi->svq->vq_ops->kick(vi->svq);
|
2008-05-03 04:50:46 +02:00
|
|
|
return NETDEV_TX_OK;
|
|
|
|
|
|
|
|
stop_queue:
|
|
|
|
pr_debug("%s: virtio not prepared to send\n", dev->name);
|
|
|
|
netif_stop_queue(dev);
|
|
|
|
|
|
|
|
/* Activate callback for using skbs: if this returns false it
|
|
|
|
* means some were used in the meantime. */
|
|
|
|
if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
|
|
|
|
vi->svq->vq_ops->disable_cb(vi->svq);
|
|
|
|
netif_start_queue(dev);
|
|
|
|
goto again;
|
|
|
|
}
|
virtio: fix virtio_net xmit of freed skb bug
On Mon, 2008-05-26 at 17:42 +1000, Rusty Russell wrote:
> If we fail to transmit a packet, we assume the queue is full and put
> the skb into last_xmit_skb. However, if more space frees up before we
> xmit it, we loop, and the result can be transmitting the same skb twice.
>
> Fix is simple: set skb to NULL if we've used it in some way, and check
> before sending.
...
> diff -r 564237b31993 drivers/net/virtio_net.c
> --- a/drivers/net/virtio_net.c Mon May 19 12:22:00 2008 +1000
> +++ b/drivers/net/virtio_net.c Mon May 19 12:24:58 2008 +1000
> @@ -287,21 +287,25 @@ again:
> free_old_xmit_skbs(vi);
>
> /* If we has a buffer left over from last time, send it now. */
> - if (vi->last_xmit_skb) {
> + if (unlikely(vi->last_xmit_skb)) {
> if (xmit_skb(vi, vi->last_xmit_skb) != 0) {
> /* Drop this skb: we only queue one. */
> vi->dev->stats.tx_dropped++;
> kfree_skb(skb);
> + skb = NULL;
> goto stop_queue;
> }
> vi->last_xmit_skb = NULL;
With this, may drop an skb and then later in the function discover that
we could have sent it after all. Poor wee skb :)
How about the incremental patch below?
Cheers,
Mark.
Subject: [PATCH] virtio_net: Delay dropping tx skbs
Currently we drop the skb in start_xmit() if we have a
queued buffer and fail to transmit it.
However, if we delay dropping it until we've stopped the
queue and enabled the tx notification callback, then there
is a chance space might become available for it.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-27 13:06:26 +02:00
|
|
|
if (skb) {
|
|
|
|
/* Drop this skb: we only queue one. */
|
|
|
|
vi->dev->stats.tx_dropped++;
|
|
|
|
kfree_skb(skb);
|
|
|
|
}
|
2008-05-03 04:50:46 +02:00
|
|
|
goto done;
|
2007-10-22 03:03:37 +02:00
|
|
|
}
|
|
|
|
|
2008-02-29 11:54:50 +01:00
|
|
|
#ifdef CONFIG_NET_POLL_CONTROLLER
|
|
|
|
static void virtnet_netpoll(struct net_device *dev)
|
|
|
|
{
|
|
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
|
|
|
|
|
|
napi_schedule(&vi->napi);
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
2007-10-22 03:03:37 +02:00
|
|
|
static int virtnet_open(struct net_device *dev)
|
|
|
|
{
|
|
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
|
|
|
|
|
|
napi_enable(&vi->napi);
|
2008-02-05 05:50:07 +01:00
|
|
|
|
|
|
|
/* If all buffers were filled by other side before we napi_enabled, we
|
|
|
|
* won't get another interrupt, so process any outstanding packets
|
virtio net: fix oops on interface-up
I got the following oops during interface ifup. Unfortunately its not
easily reproducable so I cant say for sure that my fix fixes this
problem, but I am confident and I think its correct anyway:
<2>kernel BUG at /space/kvm/drivers/virtio/virtio_ring.c:234!
<4>illegal operation: 0001 [#1] PREEMPT SMP
<4>Modules linked in:
<4>CPU: 0 Not tainted 2.6.24zlive-guest-07293-gf1ca151-dirty #91
<4>Process swapper (pid: 0, task: 0000000000800938, ksp: 000000000084ddb8)
<4>Krnl PSW : 0404300180000000 0000000000466374 (vring_disable_cb+0x30/0x34)
<4> R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:3 PM:0 EA:3
<4>Krnl GPRS: 0000000000000001 0000000000000001 0000000010003800 0000000000466344
<4> 000000000e980900 00000000008848b0 000000000084e748 0000000000000000
<4> 000000000087b300 0000000000001237 0000000000001237 000000000f85bdd8
<4> 000000000e980920 00000000001137c0 0000000000464754 000000000f85bdd8
<4>Krnl Code: 0000000000466368: e3b0b0700004 lg %r11,112(%r11)
<4> 000000000046636e: 07fe bcr 15,%r14
<4> 0000000000466370: a7f40001 brc 15,466372
<4> >0000000000466374: a7f4fff6 brc 15,466360
<4> 0000000000466378: eb7ff0500024 stmg %r7,%r15,80(%r15)
<4> 000000000046637e: a7f13e00 tmll %r15,15872
<4> 0000000000466382: b90400ef lgr %r14,%r15
<4> 0000000000466386: a7840001 brc 8,466388
<4>Call Trace:
<4>([<000201500f85c000>] 0x201500f85c000)
<4> [<0000000000466556>] vring_interrupt+0x72/0x88
<4> [<00000000004801a0>] kvm_extint_handler+0x34/0x44
<4> [<000000000010d22c>] do_extint+0xbc/0xf8
<4> [<0000000000113f98>] ext_no_vtime+0x16/0x1a
<4> [<000000000010a182>] cpu_idle+0x216/0x238
<4>([<000000000010a162>] cpu_idle+0x1f6/0x238)
<4> [<0000000000568656>] rest_init+0xaa/0xb8
<4> [<000000000084ee2c>] start_kernel+0x3fc/0x490
<4> [<0000000000100020>] _stext+0x20/0x80
<4>
<4> <0>Kernel panic - not syncing: Fatal exception in interrupt
<4>
After looking at the code and the dump I think the following scenario
happened: Ifup was running on cpu2 and the interrupt arrived on cpu0.
Now virtnet_open on cpu 2 managed to execute napi_enable and disable_cb
but did not execute rx_schedule. Meanwhile on cpu 0 skb_recv_done was
called by vring_interrupt, executed netif_rx_schedule_prep, which
succeeded and therefore called disable_cb. This triggered the BUG_ON,
as interrupts were already disabled by cpu 2.
I think the proper solution is to make the call to disable_cb depend on
the atomic update of NAPI_STATE_SCHED by using netif_rx_schedule_prep
in the same way as skb_recv_done.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-02-06 08:50:11 +01:00
|
|
|
* now. virtnet_poll wants re-enable the queue, so we disable here.
|
|
|
|
* We synchronize against interrupts via NAPI_STATE_SCHED */
|
|
|
|
if (netif_rx_schedule_prep(dev, &vi->napi)) {
|
|
|
|
vi->rvq->vq_ops->disable_cb(vi->rvq);
|
|
|
|
__netif_rx_schedule(dev, &vi->napi);
|
|
|
|
}
|
2007-10-22 03:03:37 +02:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int virtnet_close(struct net_device *dev)
|
|
|
|
{
|
|
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
|
|
|
|
|
|
napi_disable(&vi->napi);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2008-04-18 05:21:42 +02:00
|
|
|
static int virtnet_set_tx_csum(struct net_device *dev, u32 data)
|
|
|
|
{
|
|
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
|
|
struct virtio_device *vdev = vi->vdev;
|
|
|
|
|
|
|
|
if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM))
|
|
|
|
return -ENOSYS;
|
|
|
|
|
|
|
|
return ethtool_op_set_tx_hw_csum(dev, data);
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct ethtool_ops virtnet_ethtool_ops = {
|
|
|
|
.set_tx_csum = virtnet_set_tx_csum,
|
|
|
|
.set_sg = ethtool_op_set_sg,
|
2008-11-17 07:40:36 +01:00
|
|
|
.set_tso = ethtool_op_set_tso,
|
2008-04-18 05:21:42 +02:00
|
|
|
};
|
|
|
|
|
2008-11-26 14:58:11 +01:00
|
|
|
#define MIN_MTU 68
|
|
|
|
#define MAX_MTU 65535
|
|
|
|
|
|
|
|
static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
|
|
|
|
{
|
|
|
|
if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
|
|
|
|
return -EINVAL;
|
|
|
|
dev->mtu = new_mtu;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2007-10-22 03:03:37 +02:00
|
|
|
static int virtnet_probe(struct virtio_device *vdev)
|
|
|
|
{
|
|
|
|
int err;
|
|
|
|
struct net_device *dev;
|
|
|
|
struct virtnet_info *vi;
|
|
|
|
|
|
|
|
/* Allocate ourselves a network device with room for our info */
|
|
|
|
dev = alloc_etherdev(sizeof(struct virtnet_info));
|
|
|
|
if (!dev)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
/* Set up network device as normal. */
|
|
|
|
dev->open = virtnet_open;
|
|
|
|
dev->stop = virtnet_close;
|
|
|
|
dev->hard_start_xmit = start_xmit;
|
2008-11-26 14:58:11 +01:00
|
|
|
dev->change_mtu = virtnet_change_mtu;
|
2007-10-22 03:03:37 +02:00
|
|
|
dev->features = NETIF_F_HIGHDMA;
|
2008-02-29 11:54:50 +01:00
|
|
|
#ifdef CONFIG_NET_POLL_CONTROLLER
|
|
|
|
dev->poll_controller = virtnet_netpoll;
|
|
|
|
#endif
|
2008-04-18 05:21:42 +02:00
|
|
|
SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
|
2007-10-22 03:03:37 +02:00
|
|
|
SET_NETDEV_DEV(dev, &vdev->dev);
|
|
|
|
|
|
|
|
/* Do we support "hardware" checksums? */
|
2008-05-03 04:50:50 +02:00
|
|
|
if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
|
2007-10-22 03:03:37 +02:00
|
|
|
/* This opens up the world of extra features. */
|
|
|
|
dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
|
2008-05-03 04:50:50 +02:00
|
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
|
2008-02-05 05:50:02 +01:00
|
|
|
dev->features |= NETIF_F_TSO | NETIF_F_UFO
|
|
|
|
| NETIF_F_TSO_ECN | NETIF_F_TSO6;
|
|
|
|
}
|
2008-05-03 04:50:46 +02:00
|
|
|
/* Individual feature bits: what can host handle? */
|
2008-05-03 04:50:50 +02:00
|
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
|
2008-05-03 04:50:46 +02:00
|
|
|
dev->features |= NETIF_F_TSO;
|
2008-05-03 04:50:50 +02:00
|
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
|
2008-05-03 04:50:46 +02:00
|
|
|
dev->features |= NETIF_F_TSO6;
|
2008-05-03 04:50:50 +02:00
|
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
|
2008-05-03 04:50:46 +02:00
|
|
|
dev->features |= NETIF_F_TSO_ECN;
|
2008-05-03 04:50:50 +02:00
|
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
|
2008-05-03 04:50:46 +02:00
|
|
|
dev->features |= NETIF_F_UFO;
|
2007-10-22 03:03:37 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Configuration may specify what MAC to use. Otherwise random. */
|
2008-05-03 04:50:50 +02:00
|
|
|
if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
|
2008-02-05 05:49:56 +01:00
|
|
|
vdev->config->get(vdev,
|
|
|
|
offsetof(struct virtio_net_config, mac),
|
|
|
|
dev->dev_addr, dev->addr_len);
|
2007-10-22 03:03:37 +02:00
|
|
|
} else
|
|
|
|
random_ether_addr(dev->dev_addr);
|
|
|
|
|
|
|
|
/* Set up our device-specific information */
|
|
|
|
vi = netdev_priv(dev);
|
2007-12-16 14:19:43 +01:00
|
|
|
netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
|
2007-10-22 03:03:37 +02:00
|
|
|
vi->dev = dev;
|
|
|
|
vi->vdev = vdev;
|
2008-02-18 10:02:51 +01:00
|
|
|
vdev->priv = vi;
|
2008-07-25 19:06:01 +02:00
|
|
|
vi->pages = NULL;
|
2007-10-22 03:03:37 +02:00
|
|
|
|
2008-06-08 12:51:55 +02:00
|
|
|
/* If they give us a callback when all buffers are done, we don't need
|
|
|
|
* the timer. */
|
|
|
|
vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY);
|
|
|
|
|
2008-04-18 05:24:27 +02:00
|
|
|
/* If we can receive ANY GSO packets, we must allocate large ones. */
|
|
|
|
if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4)
|
|
|
|
|| virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)
|
|
|
|
|| virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
|
|
|
|
vi->big_packets = true;
|
|
|
|
|
2008-11-17 07:41:34 +01:00
|
|
|
if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
|
|
|
|
vi->mergeable_rx_bufs = true;
|
|
|
|
|
2007-10-22 03:03:37 +02:00
|
|
|
/* We expect two virtqueues, receive then send. */
|
2008-02-05 05:49:56 +01:00
|
|
|
vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
|
2007-10-22 03:03:37 +02:00
|
|
|
if (IS_ERR(vi->rvq)) {
|
|
|
|
err = PTR_ERR(vi->rvq);
|
|
|
|
goto free;
|
|
|
|
}
|
|
|
|
|
2008-02-05 05:49:56 +01:00
|
|
|
vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done);
|
2007-10-22 03:03:37 +02:00
|
|
|
if (IS_ERR(vi->svq)) {
|
|
|
|
err = PTR_ERR(vi->svq);
|
|
|
|
goto free_recv;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Initialize our empty receive and send queues. */
|
|
|
|
skb_queue_head_init(&vi->recv);
|
|
|
|
skb_queue_head_init(&vi->send);
|
|
|
|
|
2008-05-26 09:48:13 +02:00
|
|
|
tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi);
|
|
|
|
|
2008-06-08 12:51:55 +02:00
|
|
|
if (!vi->free_in_tasklet)
|
|
|
|
setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi);
|
2008-06-08 12:50:56 +02:00
|
|
|
|
2007-10-22 03:03:37 +02:00
|
|
|
err = register_netdev(dev);
|
|
|
|
if (err) {
|
|
|
|
pr_debug("virtio_net: registering device failed\n");
|
|
|
|
goto free_send;
|
|
|
|
}
|
2008-02-05 05:50:02 +01:00
|
|
|
|
|
|
|
/* Last of all, set up some receive buffers. */
|
|
|
|
try_fill_recv(vi);
|
|
|
|
|
|
|
|
/* If we didn't even get one input buffer, we're useless. */
|
|
|
|
if (vi->num == 0) {
|
|
|
|
err = -ENOMEM;
|
|
|
|
goto unregister;
|
|
|
|
}
|
|
|
|
|
2007-10-22 03:03:37 +02:00
|
|
|
pr_debug("virtnet: registered device %s\n", dev->name);
|
|
|
|
return 0;
|
|
|
|
|
2008-02-05 05:50:02 +01:00
|
|
|
unregister:
|
|
|
|
unregister_netdev(dev);
|
2007-10-22 03:03:37 +02:00
|
|
|
free_send:
|
|
|
|
vdev->config->del_vq(vi->svq);
|
|
|
|
free_recv:
|
|
|
|
vdev->config->del_vq(vi->rvq);
|
|
|
|
free:
|
|
|
|
free_netdev(dev);
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void virtnet_remove(struct virtio_device *vdev)
|
|
|
|
{
|
2007-11-19 17:20:42 +01:00
|
|
|
struct virtnet_info *vi = vdev->priv;
|
2008-02-05 05:50:02 +01:00
|
|
|
struct sk_buff *skb;
|
|
|
|
|
2008-02-05 05:50:03 +01:00
|
|
|
/* Stop all the virtqueues. */
|
|
|
|
vdev->config->reset(vdev);
|
|
|
|
|
2008-06-08 12:51:55 +02:00
|
|
|
if (!vi->free_in_tasklet)
|
|
|
|
del_timer_sync(&vi->xmit_free_timer);
|
2008-06-08 12:50:56 +02:00
|
|
|
|
2008-02-05 05:50:02 +01:00
|
|
|
/* Free our skbs in send and recv queues, if any. */
|
|
|
|
while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
|
|
|
|
kfree_skb(skb);
|
|
|
|
vi->num--;
|
|
|
|
}
|
2008-05-22 12:07:43 +02:00
|
|
|
__skb_queue_purge(&vi->send);
|
2008-02-05 05:50:02 +01:00
|
|
|
|
|
|
|
BUG_ON(vi->num != 0);
|
2007-11-19 17:20:42 +01:00
|
|
|
|
|
|
|
vdev->config->del_vq(vi->svq);
|
|
|
|
vdev->config->del_vq(vi->rvq);
|
|
|
|
unregister_netdev(vi->dev);
|
2008-07-25 19:06:01 +02:00
|
|
|
|
|
|
|
while (vi->pages)
|
|
|
|
__free_pages(get_a_page(vi, GFP_KERNEL), 0);
|
|
|
|
|
2007-11-19 17:20:42 +01:00
|
|
|
free_netdev(vi->dev);
|
2007-10-22 03:03:37 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
static struct virtio_device_id id_table[] = {
|
|
|
|
{ VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
|
|
|
|
{ 0 },
|
|
|
|
};
|
|
|
|
|
2008-05-03 04:50:50 +02:00
|
|
|
static unsigned int features[] = {
|
2008-07-08 09:10:42 +02:00
|
|
|
VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
|
|
|
|
VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
|
2008-05-03 04:50:50 +02:00
|
|
|
VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
|
2008-04-18 05:24:27 +02:00
|
|
|
VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
|
|
|
|
VIRTIO_NET_F_GUEST_ECN, /* We don't yet handle UFO input. */
|
2008-11-17 07:41:34 +01:00
|
|
|
VIRTIO_NET_F_MRG_RXBUF,
|
2008-04-18 05:24:27 +02:00
|
|
|
VIRTIO_F_NOTIFY_ON_EMPTY,
|
2008-05-03 04:50:50 +02:00
|
|
|
};
|
|
|
|
|
2007-10-22 03:03:37 +02:00
|
|
|
static struct virtio_driver virtio_net = {
|
2008-05-03 04:50:50 +02:00
|
|
|
.feature_table = features,
|
|
|
|
.feature_table_size = ARRAY_SIZE(features),
|
2007-10-22 03:03:37 +02:00
|
|
|
.driver.name = KBUILD_MODNAME,
|
|
|
|
.driver.owner = THIS_MODULE,
|
|
|
|
.id_table = id_table,
|
|
|
|
.probe = virtnet_probe,
|
|
|
|
.remove = __devexit_p(virtnet_remove),
|
|
|
|
};
|
|
|
|
|
|
|
|
static int __init init(void)
|
|
|
|
{
|
|
|
|
return register_virtio_driver(&virtio_net);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void __exit fini(void)
|
|
|
|
{
|
|
|
|
unregister_virtio_driver(&virtio_net);
|
|
|
|
}
|
|
|
|
module_init(init);
|
|
|
|
module_exit(fini);
|
|
|
|
|
|
|
|
MODULE_DEVICE_TABLE(virtio, id_table);
|
|
|
|
MODULE_DESCRIPTION("Virtio network driver");
|
|
|
|
MODULE_LICENSE("GPL");
|