1097 lines
28 KiB
C
1097 lines
28 KiB
C
/* A 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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#include <linux/ethtool.h>
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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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#include <linux/if_vlan.h>
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#include <linux/slab.h>
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static int napi_weight = 128;
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module_param(napi_weight, int, 0444);
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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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/* FIXME: MTU in config. */
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#define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
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#define GOOD_COPY_LEN 128
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#define VIRTNET_SEND_COMMAND_SG_MAX 2
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struct virtnet_info {
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struct virtio_device *vdev;
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struct virtqueue *rvq, *svq, *cvq;
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struct net_device *dev;
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struct napi_struct napi;
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unsigned int status;
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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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/* I like... big packets and I cannot lie! */
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bool big_packets;
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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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/* Work struct for refilling if we run low on memory. */
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struct delayed_work refill;
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/* Chain pages by the private ptr. */
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struct page *pages;
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/* fragments + linear part + virtio header */
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struct scatterlist rx_sg[MAX_SKB_FRAGS + 2];
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struct scatterlist tx_sg[MAX_SKB_FRAGS + 2];
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};
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struct skb_vnet_hdr {
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union {
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struct virtio_net_hdr hdr;
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struct virtio_net_hdr_mrg_rxbuf mhdr;
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};
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unsigned int num_sg;
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};
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struct padded_vnet_hdr {
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struct virtio_net_hdr hdr;
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/*
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* virtio_net_hdr should be in a separated sg buffer because of a
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* QEMU bug, and data sg buffer shares same page with this header sg.
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* This padding makes next sg 16 byte aligned after virtio_net_hdr.
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*/
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char padding[6];
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};
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static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb)
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{
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return (struct skb_vnet_hdr *)skb->cb;
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}
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/*
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* private is used to chain pages for big packets, put the whole
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* most recent used list in the beginning for reuse
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*/
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static void give_pages(struct virtnet_info *vi, struct page *page)
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{
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struct page *end;
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/* Find end of list, sew whole thing into vi->pages. */
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for (end = page; end->private; end = (struct page *)end->private);
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end->private = (unsigned long)vi->pages;
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vi->pages = page;
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}
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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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/* clear private here, it is used to chain pages */
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p->private = 0;
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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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static void skb_xmit_done(struct virtqueue *svq)
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{
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struct virtnet_info *vi = svq->vdev->priv;
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/* Suppress further interrupts. */
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virtqueue_disable_cb(svq);
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/* We were probably waiting for more output buffers. */
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netif_wake_queue(vi->dev);
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}
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static void set_skb_frag(struct sk_buff *skb, struct page *page,
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unsigned int offset, unsigned int *len)
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{
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int i = skb_shinfo(skb)->nr_frags;
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skb_frag_t *f;
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f = &skb_shinfo(skb)->frags[i];
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f->size = min((unsigned)PAGE_SIZE - offset, *len);
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f->page_offset = offset;
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f->page = page;
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skb->data_len += f->size;
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skb->len += f->size;
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skb_shinfo(skb)->nr_frags++;
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*len -= f->size;
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}
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static struct sk_buff *page_to_skb(struct virtnet_info *vi,
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struct page *page, unsigned int len)
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{
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struct sk_buff *skb;
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struct skb_vnet_hdr *hdr;
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unsigned int copy, hdr_len, offset;
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char *p;
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p = page_address(page);
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/* copy small packet so we can reuse these pages for small data */
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skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN);
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if (unlikely(!skb))
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return NULL;
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hdr = skb_vnet_hdr(skb);
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if (vi->mergeable_rx_bufs) {
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hdr_len = sizeof hdr->mhdr;
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offset = hdr_len;
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} else {
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hdr_len = sizeof hdr->hdr;
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offset = sizeof(struct padded_vnet_hdr);
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}
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memcpy(hdr, p, hdr_len);
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len -= hdr_len;
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p += offset;
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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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offset += copy;
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while (len) {
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set_skb_frag(skb, page, offset, &len);
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page = (struct page *)page->private;
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offset = 0;
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}
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if (page)
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give_pages(vi, page);
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return skb;
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}
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static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb)
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{
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struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
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struct page *page;
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int num_buf, i, len;
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num_buf = hdr->mhdr.num_buffers;
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while (--num_buf) {
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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\n", skb->dev->name);
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skb->dev->stats.rx_length_errors++;
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return -EINVAL;
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}
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page = virtqueue_get_buf(vi->rvq, &len);
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if (!page) {
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pr_debug("%s: rx error: %d buffers missing\n",
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skb->dev->name, hdr->mhdr.num_buffers);
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skb->dev->stats.rx_length_errors++;
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return -EINVAL;
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}
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if (len > PAGE_SIZE)
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len = PAGE_SIZE;
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set_skb_frag(skb, page, 0, &len);
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--vi->num;
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}
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return 0;
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}
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static void receive_buf(struct net_device *dev, void *buf, unsigned int len)
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{
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struct virtnet_info *vi = netdev_priv(dev);
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struct sk_buff *skb;
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struct page *page;
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struct skb_vnet_hdr *hdr;
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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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if (vi->mergeable_rx_bufs || vi->big_packets)
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give_pages(vi, buf);
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else
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dev_kfree_skb(buf);
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return;
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}
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if (!vi->mergeable_rx_bufs && !vi->big_packets) {
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skb = buf;
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len -= sizeof(struct virtio_net_hdr);
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skb_trim(skb, len);
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} else {
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page = buf;
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skb = page_to_skb(vi, page, len);
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if (unlikely(!skb)) {
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dev->stats.rx_dropped++;
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give_pages(vi, page);
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return;
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}
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if (vi->mergeable_rx_bufs)
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if (receive_mergeable(vi, skb)) {
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dev_kfree_skb(skb);
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return;
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}
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}
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hdr = skb_vnet_hdr(skb);
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skb->truesize += skb->data_len;
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dev->stats.rx_bytes += skb->len;
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dev->stats.rx_packets++;
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if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
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pr_debug("Needs csum!\n");
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if (!skb_partial_csum_set(skb,
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hdr->hdr.csum_start,
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hdr->hdr.csum_offset))
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goto frame_err;
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}
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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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if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
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pr_debug("GSO!\n");
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switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
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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->hdr.gso_type);
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goto frame_err;
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}
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if (hdr->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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skb_shinfo(skb)->gso_size = hdr->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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dev_kfree_skb(skb);
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}
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static int add_recvbuf_small(struct virtnet_info *vi, gfp_t gfp)
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{
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struct sk_buff *skb;
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struct skb_vnet_hdr *hdr;
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int err;
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skb = netdev_alloc_skb_ip_align(vi->dev, MAX_PACKET_LEN);
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if (unlikely(!skb))
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return -ENOMEM;
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skb_put(skb, MAX_PACKET_LEN);
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hdr = skb_vnet_hdr(skb);
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sg_set_buf(vi->rx_sg, &hdr->hdr, sizeof hdr->hdr);
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skb_to_sgvec(skb, vi->rx_sg + 1, 0, skb->len);
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err = virtqueue_add_buf_gfp(vi->rvq, vi->rx_sg, 0, 2, skb, gfp);
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if (err < 0)
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dev_kfree_skb(skb);
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return err;
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}
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static int add_recvbuf_big(struct virtnet_info *vi, gfp_t gfp)
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{
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struct page *first, *list = NULL;
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char *p;
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int i, err, offset;
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/* page in vi->rx_sg[MAX_SKB_FRAGS + 1] is list tail */
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for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
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first = get_a_page(vi, gfp);
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if (!first) {
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if (list)
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give_pages(vi, list);
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return -ENOMEM;
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}
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sg_set_buf(&vi->rx_sg[i], page_address(first), PAGE_SIZE);
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/* chain new page in list head to match sg */
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first->private = (unsigned long)list;
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list = first;
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}
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first = get_a_page(vi, gfp);
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if (!first) {
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give_pages(vi, list);
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return -ENOMEM;
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}
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p = page_address(first);
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/* vi->rx_sg[0], vi->rx_sg[1] share the same page */
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/* a separated vi->rx_sg[0] for virtio_net_hdr only due to QEMU bug */
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sg_set_buf(&vi->rx_sg[0], p, sizeof(struct virtio_net_hdr));
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/* vi->rx_sg[1] for data packet, from offset */
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offset = sizeof(struct padded_vnet_hdr);
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sg_set_buf(&vi->rx_sg[1], p + offset, PAGE_SIZE - offset);
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/* chain first in list head */
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first->private = (unsigned long)list;
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err = virtqueue_add_buf_gfp(vi->rvq, vi->rx_sg, 0, MAX_SKB_FRAGS + 2,
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first, gfp);
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if (err < 0)
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give_pages(vi, first);
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return err;
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}
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static int add_recvbuf_mergeable(struct virtnet_info *vi, gfp_t gfp)
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{
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struct page *page;
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int err;
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page = get_a_page(vi, gfp);
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if (!page)
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return -ENOMEM;
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sg_init_one(vi->rx_sg, page_address(page), PAGE_SIZE);
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err = virtqueue_add_buf_gfp(vi->rvq, vi->rx_sg, 0, 1, page, gfp);
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if (err < 0)
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give_pages(vi, page);
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return err;
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}
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/* Returns false if we couldn't fill entirely (OOM). */
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static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
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{
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int err;
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bool oom;
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do {
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if (vi->mergeable_rx_bufs)
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err = add_recvbuf_mergeable(vi, gfp);
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else if (vi->big_packets)
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err = add_recvbuf_big(vi, gfp);
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else
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err = add_recvbuf_small(vi, gfp);
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oom = err == -ENOMEM;
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if (err < 0)
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break;
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++vi->num;
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} while (err > 0);
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if (unlikely(vi->num > vi->max))
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vi->max = vi->num;
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virtqueue_kick(vi->rvq);
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return !oom;
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}
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static void skb_recv_done(struct virtqueue *rvq)
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{
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struct virtnet_info *vi = rvq->vdev->priv;
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/* Schedule NAPI, Suppress further interrupts if successful. */
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if (napi_schedule_prep(&vi->napi)) {
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virtqueue_disable_cb(rvq);
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__napi_schedule(&vi->napi);
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}
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}
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|
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static void refill_work(struct work_struct *work)
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{
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struct virtnet_info *vi;
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bool still_empty;
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vi = container_of(work, struct virtnet_info, refill.work);
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napi_disable(&vi->napi);
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still_empty = !try_fill_recv(vi, GFP_KERNEL);
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napi_enable(&vi->napi);
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|
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/* In theory, this can happen: if we don't get any buffers in
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* we will *never* try to fill again. */
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if (still_empty)
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schedule_delayed_work(&vi->refill, HZ/2);
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}
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static int virtnet_poll(struct napi_struct *napi, int budget)
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{
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struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
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void *buf;
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unsigned int len, received = 0;
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again:
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while (received < budget &&
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(buf = virtqueue_get_buf(vi->rvq, &len)) != NULL) {
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receive_buf(vi->dev, buf, len);
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--vi->num;
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received++;
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}
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if (vi->num < vi->max / 2) {
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if (!try_fill_recv(vi, GFP_ATOMIC))
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schedule_delayed_work(&vi->refill, 0);
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}
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/* Out of packets? */
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if (received < budget) {
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napi_complete(napi);
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if (unlikely(!virtqueue_enable_cb(vi->rvq)) &&
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napi_schedule_prep(napi)) {
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virtqueue_disable_cb(vi->rvq);
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__napi_schedule(napi);
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goto again;
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}
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}
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return received;
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}
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|
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static unsigned int free_old_xmit_skbs(struct virtnet_info *vi)
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{
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struct sk_buff *skb;
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unsigned int len, tot_sgs = 0;
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|
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while ((skb = virtqueue_get_buf(vi->svq, &len)) != NULL) {
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pr_debug("Sent skb %p\n", skb);
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vi->dev->stats.tx_bytes += skb->len;
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vi->dev->stats.tx_packets++;
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tot_sgs += skb_vnet_hdr(skb)->num_sg;
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dev_kfree_skb_any(skb);
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}
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return tot_sgs;
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}
|
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|
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static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
|
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{
|
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struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
|
|
const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
|
|
|
|
pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
|
|
|
|
if (skb->ip_summed == CHECKSUM_PARTIAL) {
|
|
hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
|
|
hdr->hdr.csum_start = skb_checksum_start_offset(skb);
|
|
hdr->hdr.csum_offset = skb->csum_offset;
|
|
} else {
|
|
hdr->hdr.flags = 0;
|
|
hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
|
|
}
|
|
|
|
if (skb_is_gso(skb)) {
|
|
hdr->hdr.hdr_len = skb_headlen(skb);
|
|
hdr->hdr.gso_size = skb_shinfo(skb)->gso_size;
|
|
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
|
|
hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
|
|
else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
|
|
hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
|
|
else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
|
|
hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
|
|
else
|
|
BUG();
|
|
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
|
|
hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
|
|
} else {
|
|
hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
|
|
hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
|
|
}
|
|
|
|
hdr->mhdr.num_buffers = 0;
|
|
|
|
/* Encode metadata header at front. */
|
|
if (vi->mergeable_rx_bufs)
|
|
sg_set_buf(vi->tx_sg, &hdr->mhdr, sizeof hdr->mhdr);
|
|
else
|
|
sg_set_buf(vi->tx_sg, &hdr->hdr, sizeof hdr->hdr);
|
|
|
|
hdr->num_sg = skb_to_sgvec(skb, vi->tx_sg + 1, 0, skb->len) + 1;
|
|
return virtqueue_add_buf(vi->svq, vi->tx_sg, hdr->num_sg,
|
|
0, skb);
|
|
}
|
|
|
|
static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
int capacity;
|
|
|
|
/* Free up any pending old buffers before queueing new ones. */
|
|
free_old_xmit_skbs(vi);
|
|
|
|
/* Try to transmit */
|
|
capacity = xmit_skb(vi, skb);
|
|
|
|
/* This can happen with OOM and indirect buffers. */
|
|
if (unlikely(capacity < 0)) {
|
|
if (net_ratelimit()) {
|
|
if (likely(capacity == -ENOMEM)) {
|
|
dev_warn(&dev->dev,
|
|
"TX queue failure: out of memory\n");
|
|
} else {
|
|
dev->stats.tx_fifo_errors++;
|
|
dev_warn(&dev->dev,
|
|
"Unexpected TX queue failure: %d\n",
|
|
capacity);
|
|
}
|
|
}
|
|
dev->stats.tx_dropped++;
|
|
kfree_skb(skb);
|
|
return NETDEV_TX_OK;
|
|
}
|
|
virtqueue_kick(vi->svq);
|
|
|
|
/* Don't wait up for transmitted skbs to be freed. */
|
|
skb_orphan(skb);
|
|
nf_reset(skb);
|
|
|
|
/* Apparently nice girls don't return TX_BUSY; stop the queue
|
|
* before it gets out of hand. Naturally, this wastes entries. */
|
|
if (capacity < 2+MAX_SKB_FRAGS) {
|
|
netif_stop_queue(dev);
|
|
if (unlikely(!virtqueue_enable_cb(vi->svq))) {
|
|
/* More just got used, free them then recheck. */
|
|
capacity += free_old_xmit_skbs(vi);
|
|
if (capacity >= 2+MAX_SKB_FRAGS) {
|
|
netif_start_queue(dev);
|
|
virtqueue_disable_cb(vi->svq);
|
|
}
|
|
}
|
|
}
|
|
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
static int virtnet_set_mac_address(struct net_device *dev, void *p)
|
|
{
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
struct virtio_device *vdev = vi->vdev;
|
|
int ret;
|
|
|
|
ret = eth_mac_addr(dev, p);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
|
|
vdev->config->set(vdev, offsetof(struct virtio_net_config, mac),
|
|
dev->dev_addr, dev->addr_len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#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
|
|
|
|
static int virtnet_open(struct net_device *dev)
|
|
{
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
|
|
napi_enable(&vi->napi);
|
|
|
|
/* If all buffers were filled by other side before we napi_enabled, we
|
|
* won't get another interrupt, so process any outstanding packets
|
|
* now. virtnet_poll wants re-enable the queue, so we disable here.
|
|
* We synchronize against interrupts via NAPI_STATE_SCHED */
|
|
if (napi_schedule_prep(&vi->napi)) {
|
|
virtqueue_disable_cb(vi->rvq);
|
|
__napi_schedule(&vi->napi);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Send command via the control virtqueue and check status. Commands
|
|
* supported by the hypervisor, as indicated by feature bits, should
|
|
* never fail unless improperly formated.
|
|
*/
|
|
static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
|
|
struct scatterlist *data, int out, int in)
|
|
{
|
|
struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
|
|
struct virtio_net_ctrl_hdr ctrl;
|
|
virtio_net_ctrl_ack status = ~0;
|
|
unsigned int tmp;
|
|
int i;
|
|
|
|
/* Caller should know better */
|
|
BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ||
|
|
(out + in > VIRTNET_SEND_COMMAND_SG_MAX));
|
|
|
|
out++; /* Add header */
|
|
in++; /* Add return status */
|
|
|
|
ctrl.class = class;
|
|
ctrl.cmd = cmd;
|
|
|
|
sg_init_table(sg, out + in);
|
|
|
|
sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
|
|
for_each_sg(data, s, out + in - 2, i)
|
|
sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
|
|
sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
|
|
|
|
BUG_ON(virtqueue_add_buf(vi->cvq, sg, out, in, vi) < 0);
|
|
|
|
virtqueue_kick(vi->cvq);
|
|
|
|
/*
|
|
* Spin for a response, the kick causes an ioport write, trapping
|
|
* into the hypervisor, so the request should be handled immediately.
|
|
*/
|
|
while (!virtqueue_get_buf(vi->cvq, &tmp))
|
|
cpu_relax();
|
|
|
|
return status == VIRTIO_NET_OK;
|
|
}
|
|
|
|
static int virtnet_close(struct net_device *dev)
|
|
{
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
|
|
napi_disable(&vi->napi);
|
|
|
|
return 0;
|
|
}
|
|
|
|
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 void virtnet_set_rx_mode(struct net_device *dev)
|
|
{
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
struct scatterlist sg[2];
|
|
u8 promisc, allmulti;
|
|
struct virtio_net_ctrl_mac *mac_data;
|
|
struct netdev_hw_addr *ha;
|
|
int uc_count;
|
|
int mc_count;
|
|
void *buf;
|
|
int i;
|
|
|
|
/* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */
|
|
if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
|
|
return;
|
|
|
|
promisc = ((dev->flags & IFF_PROMISC) != 0);
|
|
allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
|
|
|
|
sg_init_one(sg, &promisc, sizeof(promisc));
|
|
|
|
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
|
|
VIRTIO_NET_CTRL_RX_PROMISC,
|
|
sg, 1, 0))
|
|
dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
|
|
promisc ? "en" : "dis");
|
|
|
|
sg_init_one(sg, &allmulti, sizeof(allmulti));
|
|
|
|
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
|
|
VIRTIO_NET_CTRL_RX_ALLMULTI,
|
|
sg, 1, 0))
|
|
dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
|
|
allmulti ? "en" : "dis");
|
|
|
|
uc_count = netdev_uc_count(dev);
|
|
mc_count = netdev_mc_count(dev);
|
|
/* MAC filter - use one buffer for both lists */
|
|
buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
|
|
(2 * sizeof(mac_data->entries)), GFP_ATOMIC);
|
|
mac_data = buf;
|
|
if (!buf) {
|
|
dev_warn(&dev->dev, "No memory for MAC address buffer\n");
|
|
return;
|
|
}
|
|
|
|
sg_init_table(sg, 2);
|
|
|
|
/* Store the unicast list and count in the front of the buffer */
|
|
mac_data->entries = uc_count;
|
|
i = 0;
|
|
netdev_for_each_uc_addr(ha, dev)
|
|
memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
|
|
|
|
sg_set_buf(&sg[0], mac_data,
|
|
sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
|
|
|
|
/* multicast list and count fill the end */
|
|
mac_data = (void *)&mac_data->macs[uc_count][0];
|
|
|
|
mac_data->entries = mc_count;
|
|
i = 0;
|
|
netdev_for_each_mc_addr(ha, dev)
|
|
memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
|
|
|
|
sg_set_buf(&sg[1], mac_data,
|
|
sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
|
|
|
|
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
|
|
VIRTIO_NET_CTRL_MAC_TABLE_SET,
|
|
sg, 2, 0))
|
|
dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
|
|
|
|
kfree(buf);
|
|
}
|
|
|
|
static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid)
|
|
{
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
struct scatterlist sg;
|
|
|
|
sg_init_one(&sg, &vid, sizeof(vid));
|
|
|
|
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
|
|
VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
|
|
dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
|
|
}
|
|
|
|
static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid)
|
|
{
|
|
struct virtnet_info *vi = netdev_priv(dev);
|
|
struct scatterlist sg;
|
|
|
|
sg_init_one(&sg, &vid, sizeof(vid));
|
|
|
|
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
|
|
VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
|
|
dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
|
|
}
|
|
|
|
static const struct ethtool_ops virtnet_ethtool_ops = {
|
|
.set_tx_csum = virtnet_set_tx_csum,
|
|
.set_sg = ethtool_op_set_sg,
|
|
.set_tso = ethtool_op_set_tso,
|
|
.set_ufo = ethtool_op_set_ufo,
|
|
.get_link = ethtool_op_get_link,
|
|
};
|
|
|
|
#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;
|
|
}
|
|
|
|
static const struct net_device_ops virtnet_netdev = {
|
|
.ndo_open = virtnet_open,
|
|
.ndo_stop = virtnet_close,
|
|
.ndo_start_xmit = start_xmit,
|
|
.ndo_validate_addr = eth_validate_addr,
|
|
.ndo_set_mac_address = virtnet_set_mac_address,
|
|
.ndo_set_rx_mode = virtnet_set_rx_mode,
|
|
.ndo_change_mtu = virtnet_change_mtu,
|
|
.ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
|
|
.ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
|
|
#ifdef CONFIG_NET_POLL_CONTROLLER
|
|
.ndo_poll_controller = virtnet_netpoll,
|
|
#endif
|
|
};
|
|
|
|
static void virtnet_update_status(struct virtnet_info *vi)
|
|
{
|
|
u16 v;
|
|
|
|
if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS))
|
|
return;
|
|
|
|
vi->vdev->config->get(vi->vdev,
|
|
offsetof(struct virtio_net_config, status),
|
|
&v, sizeof(v));
|
|
|
|
/* Ignore unknown (future) status bits */
|
|
v &= VIRTIO_NET_S_LINK_UP;
|
|
|
|
if (vi->status == v)
|
|
return;
|
|
|
|
vi->status = v;
|
|
|
|
if (vi->status & VIRTIO_NET_S_LINK_UP) {
|
|
netif_carrier_on(vi->dev);
|
|
netif_wake_queue(vi->dev);
|
|
} else {
|
|
netif_carrier_off(vi->dev);
|
|
netif_stop_queue(vi->dev);
|
|
}
|
|
}
|
|
|
|
static void virtnet_config_changed(struct virtio_device *vdev)
|
|
{
|
|
struct virtnet_info *vi = vdev->priv;
|
|
|
|
virtnet_update_status(vi);
|
|
}
|
|
|
|
static int virtnet_probe(struct virtio_device *vdev)
|
|
{
|
|
int err;
|
|
struct net_device *dev;
|
|
struct virtnet_info *vi;
|
|
struct virtqueue *vqs[3];
|
|
vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL};
|
|
const char *names[] = { "input", "output", "control" };
|
|
int nvqs;
|
|
|
|
/* 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->netdev_ops = &virtnet_netdev;
|
|
dev->features = NETIF_F_HIGHDMA;
|
|
SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
|
|
SET_NETDEV_DEV(dev, &vdev->dev);
|
|
|
|
/* Do we support "hardware" checksums? */
|
|
if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
|
|
/* This opens up the world of extra features. */
|
|
dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
|
|
dev->features |= NETIF_F_TSO | NETIF_F_UFO
|
|
| NETIF_F_TSO_ECN | NETIF_F_TSO6;
|
|
}
|
|
/* Individual feature bits: what can host handle? */
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
|
|
dev->features |= NETIF_F_TSO;
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
|
|
dev->features |= NETIF_F_TSO6;
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
|
|
dev->features |= NETIF_F_TSO_ECN;
|
|
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
|
|
dev->features |= NETIF_F_UFO;
|
|
}
|
|
|
|
/* Configuration may specify what MAC to use. Otherwise random. */
|
|
if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
|
|
vdev->config->get(vdev,
|
|
offsetof(struct virtio_net_config, mac),
|
|
dev->dev_addr, dev->addr_len);
|
|
} else
|
|
random_ether_addr(dev->dev_addr);
|
|
|
|
/* Set up our device-specific information */
|
|
vi = netdev_priv(dev);
|
|
netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
|
|
vi->dev = dev;
|
|
vi->vdev = vdev;
|
|
vdev->priv = vi;
|
|
vi->pages = NULL;
|
|
INIT_DELAYED_WORK(&vi->refill, refill_work);
|
|
sg_init_table(vi->rx_sg, ARRAY_SIZE(vi->rx_sg));
|
|
sg_init_table(vi->tx_sg, ARRAY_SIZE(vi->tx_sg));
|
|
|
|
/* 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;
|
|
|
|
if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
|
|
vi->mergeable_rx_bufs = true;
|
|
|
|
/* We expect two virtqueues, receive then send,
|
|
* and optionally control. */
|
|
nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
|
|
|
|
err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names);
|
|
if (err)
|
|
goto free;
|
|
|
|
vi->rvq = vqs[0];
|
|
vi->svq = vqs[1];
|
|
|
|
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
|
|
vi->cvq = vqs[2];
|
|
|
|
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
|
|
dev->features |= NETIF_F_HW_VLAN_FILTER;
|
|
}
|
|
|
|
err = register_netdev(dev);
|
|
if (err) {
|
|
pr_debug("virtio_net: registering device failed\n");
|
|
goto free_vqs;
|
|
}
|
|
|
|
/* Last of all, set up some receive buffers. */
|
|
try_fill_recv(vi, GFP_KERNEL);
|
|
|
|
/* If we didn't even get one input buffer, we're useless. */
|
|
if (vi->num == 0) {
|
|
err = -ENOMEM;
|
|
goto unregister;
|
|
}
|
|
|
|
/* Assume link up if device can't report link status,
|
|
otherwise get link status from config. */
|
|
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
|
|
netif_carrier_off(dev);
|
|
virtnet_update_status(vi);
|
|
} else {
|
|
vi->status = VIRTIO_NET_S_LINK_UP;
|
|
netif_carrier_on(dev);
|
|
}
|
|
|
|
pr_debug("virtnet: registered device %s\n", dev->name);
|
|
return 0;
|
|
|
|
unregister:
|
|
unregister_netdev(dev);
|
|
cancel_delayed_work_sync(&vi->refill);
|
|
free_vqs:
|
|
vdev->config->del_vqs(vdev);
|
|
free:
|
|
free_netdev(dev);
|
|
return err;
|
|
}
|
|
|
|
static void free_unused_bufs(struct virtnet_info *vi)
|
|
{
|
|
void *buf;
|
|
while (1) {
|
|
buf = virtqueue_detach_unused_buf(vi->svq);
|
|
if (!buf)
|
|
break;
|
|
dev_kfree_skb(buf);
|
|
}
|
|
while (1) {
|
|
buf = virtqueue_detach_unused_buf(vi->rvq);
|
|
if (!buf)
|
|
break;
|
|
if (vi->mergeable_rx_bufs || vi->big_packets)
|
|
give_pages(vi, buf);
|
|
else
|
|
dev_kfree_skb(buf);
|
|
--vi->num;
|
|
}
|
|
BUG_ON(vi->num != 0);
|
|
}
|
|
|
|
static void __devexit virtnet_remove(struct virtio_device *vdev)
|
|
{
|
|
struct virtnet_info *vi = vdev->priv;
|
|
|
|
/* Stop all the virtqueues. */
|
|
vdev->config->reset(vdev);
|
|
|
|
|
|
unregister_netdev(vi->dev);
|
|
cancel_delayed_work_sync(&vi->refill);
|
|
|
|
/* Free unused buffers in both send and recv, if any. */
|
|
free_unused_bufs(vi);
|
|
|
|
vdev->config->del_vqs(vi->vdev);
|
|
|
|
while (vi->pages)
|
|
__free_pages(get_a_page(vi, GFP_KERNEL), 0);
|
|
|
|
free_netdev(vi->dev);
|
|
}
|
|
|
|
static struct virtio_device_id id_table[] = {
|
|
{ VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
|
|
{ 0 },
|
|
};
|
|
|
|
static unsigned int features[] = {
|
|
VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
|
|
VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
|
|
VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
|
|
VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
|
|
VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
|
|
VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
|
|
VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
|
|
};
|
|
|
|
static struct virtio_driver virtio_net_driver = {
|
|
.feature_table = features,
|
|
.feature_table_size = ARRAY_SIZE(features),
|
|
.driver.name = KBUILD_MODNAME,
|
|
.driver.owner = THIS_MODULE,
|
|
.id_table = id_table,
|
|
.probe = virtnet_probe,
|
|
.remove = __devexit_p(virtnet_remove),
|
|
.config_changed = virtnet_config_changed,
|
|
};
|
|
|
|
static int __init init(void)
|
|
{
|
|
return register_virtio_driver(&virtio_net_driver);
|
|
}
|
|
|
|
static void __exit fini(void)
|
|
{
|
|
unregister_virtio_driver(&virtio_net_driver);
|
|
}
|
|
module_init(init);
|
|
module_exit(fini);
|
|
|
|
MODULE_DEVICE_TABLE(virtio, id_table);
|
|
MODULE_DESCRIPTION("Virtio network driver");
|
|
MODULE_LICENSE("GPL");
|