| /* A network driver using virtio. |
| * |
| * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| //#define DEBUG |
| #include <linux/netdevice.h> |
| #include <linux/etherdevice.h> |
| #include <linux/ethtool.h> |
| #include <linux/module.h> |
| #include <linux/virtio.h> |
| #include <linux/virtio_net.h> |
| #include <linux/scatterlist.h> |
| #include <linux/if_vlan.h> |
| #include <linux/slab.h> |
| |
| static int napi_weight = 128; |
| module_param(napi_weight, int, 0444); |
| |
| static int csum = 1, gso = 1; |
| module_param(csum, bool, 0444); |
| module_param(gso, bool, 0444); |
| |
| /* FIXME: MTU in config. */ |
| #define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) |
| #define GOOD_COPY_LEN 128 |
| |
| #define VIRTNET_SEND_COMMAND_SG_MAX 2 |
| #define VIRTNET_DRIVER_VERSION "1.0.0" |
| |
| struct virtnet_stats { |
| struct u64_stats_sync syncp; |
| u64 tx_bytes; |
| u64 tx_packets; |
| |
| u64 rx_bytes; |
| u64 rx_packets; |
| }; |
| |
| struct virtnet_info { |
| struct virtio_device *vdev; |
| struct virtqueue *rvq, *svq, *cvq; |
| struct net_device *dev; |
| struct napi_struct napi; |
| unsigned int status; |
| |
| /* Number of input buffers, and max we've ever had. */ |
| unsigned int num, max; |
| |
| /* I like... big packets and I cannot lie! */ |
| bool big_packets; |
| |
| /* Host will merge rx buffers for big packets (shake it! shake it!) */ |
| bool mergeable_rx_bufs; |
| |
| /* Active statistics */ |
| struct virtnet_stats __percpu *stats; |
| |
| /* Work struct for refilling if we run low on memory. */ |
| struct delayed_work refill; |
| |
| /* Chain pages by the private ptr. */ |
| struct page *pages; |
| |
| /* fragments + linear part + virtio header */ |
| struct scatterlist rx_sg[MAX_SKB_FRAGS + 2]; |
| struct scatterlist tx_sg[MAX_SKB_FRAGS + 2]; |
| }; |
| |
| struct skb_vnet_hdr { |
| union { |
| struct virtio_net_hdr hdr; |
| struct virtio_net_hdr_mrg_rxbuf mhdr; |
| }; |
| unsigned int num_sg; |
| }; |
| |
| struct padded_vnet_hdr { |
| struct virtio_net_hdr hdr; |
| /* |
| * virtio_net_hdr should be in a separated sg buffer because of a |
| * QEMU bug, and data sg buffer shares same page with this header sg. |
| * This padding makes next sg 16 byte aligned after virtio_net_hdr. |
| */ |
| char padding[6]; |
| }; |
| |
| static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb) |
| { |
| return (struct skb_vnet_hdr *)skb->cb; |
| } |
| |
| /* |
| * private is used to chain pages for big packets, put the whole |
| * most recent used list in the beginning for reuse |
| */ |
| static void give_pages(struct virtnet_info *vi, struct page *page) |
| { |
| struct page *end; |
| |
| /* Find end of list, sew whole thing into vi->pages. */ |
| for (end = page; end->private; end = (struct page *)end->private); |
| end->private = (unsigned long)vi->pages; |
| vi->pages = page; |
| } |
| |
| static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask) |
| { |
| struct page *p = vi->pages; |
| |
| if (p) { |
| vi->pages = (struct page *)p->private; |
| /* clear private here, it is used to chain pages */ |
| p->private = 0; |
| } else |
| p = alloc_page(gfp_mask); |
| return p; |
| } |
| |
| static void skb_xmit_done(struct virtqueue *svq) |
| { |
| struct virtnet_info *vi = svq->vdev->priv; |
| |
| /* Suppress further interrupts. */ |
| virtqueue_disable_cb(svq); |
| |
| /* We were probably waiting for more output buffers. */ |
| netif_wake_queue(vi->dev); |
| } |
| |
| static void set_skb_frag(struct sk_buff *skb, struct page *page, |
| unsigned int offset, unsigned int *len) |
| { |
| int size = min((unsigned)PAGE_SIZE - offset, *len); |
| int i = skb_shinfo(skb)->nr_frags; |
| |
| __skb_fill_page_desc(skb, i, page, offset, size); |
| |
| skb->data_len += size; |
| skb->len += size; |
| skb->truesize += PAGE_SIZE; |
| skb_shinfo(skb)->nr_frags++; |
| *len -= size; |
| } |
| |
| static struct sk_buff *page_to_skb(struct virtnet_info *vi, |
| struct page *page, unsigned int len) |
| { |
| struct sk_buff *skb; |
| struct skb_vnet_hdr *hdr; |
| unsigned int copy, hdr_len, offset; |
| char *p; |
| |
| p = page_address(page); |
| |
| /* copy small packet so we can reuse these pages for small data */ |
| skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN); |
| if (unlikely(!skb)) |
| return NULL; |
| |
| hdr = skb_vnet_hdr(skb); |
| |
| if (vi->mergeable_rx_bufs) { |
| hdr_len = sizeof hdr->mhdr; |
| offset = hdr_len; |
| } else { |
| hdr_len = sizeof hdr->hdr; |
| offset = sizeof(struct padded_vnet_hdr); |
| } |
| |
| memcpy(hdr, p, hdr_len); |
| |
| len -= hdr_len; |
| p += offset; |
| |
| copy = len; |
| if (copy > skb_tailroom(skb)) |
| copy = skb_tailroom(skb); |
| memcpy(skb_put(skb, copy), p, copy); |
| |
| len -= copy; |
| offset += copy; |
| |
| /* |
| * Verify that we can indeed put this data into a skb. |
| * This is here to handle cases when the device erroneously |
| * tries to receive more than is possible. This is usually |
| * the case of a broken device. |
| */ |
| if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) { |
| if (net_ratelimit()) |
| pr_debug("%s: too much data\n", skb->dev->name); |
| dev_kfree_skb(skb); |
| return NULL; |
| } |
| |
| while (len) { |
| set_skb_frag(skb, page, offset, &len); |
| page = (struct page *)page->private; |
| offset = 0; |
| } |
| |
| if (page) |
| give_pages(vi, page); |
| |
| return skb; |
| } |
| |
| static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb) |
| { |
| struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb); |
| struct page *page; |
| int num_buf, i, len; |
| |
| num_buf = hdr->mhdr.num_buffers; |
| while (--num_buf) { |
| i = skb_shinfo(skb)->nr_frags; |
| if (i >= MAX_SKB_FRAGS) { |
| pr_debug("%s: packet too long\n", skb->dev->name); |
| skb->dev->stats.rx_length_errors++; |
| return -EINVAL; |
| } |
| page = virtqueue_get_buf(vi->rvq, &len); |
| if (!page) { |
| pr_debug("%s: rx error: %d buffers missing\n", |
| skb->dev->name, hdr->mhdr.num_buffers); |
| skb->dev->stats.rx_length_errors++; |
| return -EINVAL; |
| } |
| |
| if (len > PAGE_SIZE) |
| len = PAGE_SIZE; |
| |
| set_skb_frag(skb, page, 0, &len); |
| |
| --vi->num; |
| } |
| return 0; |
| } |
| |
| static void receive_buf(struct net_device *dev, void *buf, unsigned int len) |
| { |
| struct virtnet_info *vi = netdev_priv(dev); |
| struct virtnet_stats __percpu *stats = this_cpu_ptr(vi->stats); |
| struct sk_buff *skb; |
| struct page *page; |
| struct skb_vnet_hdr *hdr; |
| |
| if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) { |
| pr_debug("%s: short packet %i\n", dev->name, len); |
| dev->stats.rx_length_errors++; |
| if (vi->mergeable_rx_bufs || vi->big_packets) |
| give_pages(vi, buf); |
| else |
| dev_kfree_skb(buf); |
| return; |
| } |
| |
| if (!vi->mergeable_rx_bufs && !vi->big_packets) { |
| skb = buf; |
| len -= sizeof(struct virtio_net_hdr); |
| skb_trim(skb, len); |
| } else { |
| page = buf; |
| skb = page_to_skb(vi, page, len); |
| if (unlikely(!skb)) { |
| dev->stats.rx_dropped++; |
| give_pages(vi, page); |
| return; |
| } |
| if (vi->mergeable_rx_bufs) |
| if (receive_mergeable(vi, skb)) { |
| dev_kfree_skb(skb); |
| return; |
| } |
| } |
| |
| hdr = skb_vnet_hdr(skb); |
| |
| u64_stats_update_begin(&stats->syncp); |
| stats->rx_bytes += skb->len; |
| stats->rx_packets++; |
| u64_stats_update_end(&stats->syncp); |
| |
| if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { |
| pr_debug("Needs csum!\n"); |
| if (!skb_partial_csum_set(skb, |
| hdr->hdr.csum_start, |
| hdr->hdr.csum_offset)) |
| goto frame_err; |
| } else if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID) { |
| skb->ip_summed = CHECKSUM_UNNECESSARY; |
| } |
| |
| skb->protocol = eth_type_trans(skb, dev); |
| pr_debug("Receiving skb proto 0x%04x len %i type %i\n", |
| ntohs(skb->protocol), skb->len, skb->pkt_type); |
| |
| if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) { |
| pr_debug("GSO!\n"); |
| switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { |
| case VIRTIO_NET_HDR_GSO_TCPV4: |
| skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; |
| break; |
| case VIRTIO_NET_HDR_GSO_UDP: |
| skb_shinfo(skb)->gso_type = SKB_GSO_UDP; |
| break; |
| case VIRTIO_NET_HDR_GSO_TCPV6: |
| skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; |
| break; |
| default: |
| if (net_ratelimit()) |
| printk(KERN_WARNING "%s: bad gso type %u.\n", |
| dev->name, hdr->hdr.gso_type); |
| goto frame_err; |
| } |
| |
| if (hdr->hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN) |
| skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; |
| |
| skb_shinfo(skb)->gso_size = hdr->hdr.gso_size; |
| if (skb_shinfo(skb)->gso_size == 0) { |
| if (net_ratelimit()) |
| printk(KERN_WARNING "%s: zero gso size.\n", |
| dev->name); |
| goto frame_err; |
| } |
| |
| /* Header must be checked, and gso_segs computed. */ |
| skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; |
| skb_shinfo(skb)->gso_segs = 0; |
| } |
| |
| netif_receive_skb(skb); |
| return; |
| |
| frame_err: |
| dev->stats.rx_frame_errors++; |
| dev_kfree_skb(skb); |
| } |
| |
| static int add_recvbuf_small(struct virtnet_info *vi, gfp_t gfp) |
| { |
| struct sk_buff *skb; |
| struct skb_vnet_hdr *hdr; |
| int err; |
| |
| skb = netdev_alloc_skb_ip_align(vi->dev, MAX_PACKET_LEN); |
| if (unlikely(!skb)) |
| return -ENOMEM; |
| |
| skb_put(skb, MAX_PACKET_LEN); |
| |
| hdr = skb_vnet_hdr(skb); |
| sg_set_buf(vi->rx_sg, &hdr->hdr, sizeof hdr->hdr); |
| |
| skb_to_sgvec(skb, vi->rx_sg + 1, 0, skb->len); |
| |
| err = virtqueue_add_buf_gfp(vi->rvq, vi->rx_sg, 0, 2, skb, gfp); |
| if (err < 0) |
| dev_kfree_skb(skb); |
| |
| return err; |
| } |
| |
| static int add_recvbuf_big(struct virtnet_info *vi, gfp_t gfp) |
| { |
| struct page *first, *list = NULL; |
| char *p; |
| int i, err, offset; |
| |
| /* page in vi->rx_sg[MAX_SKB_FRAGS + 1] is list tail */ |
| for (i = MAX_SKB_FRAGS + 1; i > 1; --i) { |
| first = get_a_page(vi, gfp); |
| if (!first) { |
| if (list) |
| give_pages(vi, list); |
| return -ENOMEM; |
| } |
| sg_set_buf(&vi->rx_sg[i], page_address(first), PAGE_SIZE); |
| |
| /* chain new page in list head to match sg */ |
| first->private = (unsigned long)list; |
| list = first; |
| } |
| |
| first = get_a_page(vi, gfp); |
| if (!first) { |
| give_pages(vi, list); |
| return -ENOMEM; |
| } |
| p = page_address(first); |
| |
| /* vi->rx_sg[0], vi->rx_sg[1] share the same page */ |
| /* a separated vi->rx_sg[0] for virtio_net_hdr only due to QEMU bug */ |
| sg_set_buf(&vi->rx_sg[0], p, sizeof(struct virtio_net_hdr)); |
| |
| /* vi->rx_sg[1] for data packet, from offset */ |
| offset = sizeof(struct padded_vnet_hdr); |
| sg_set_buf(&vi->rx_sg[1], p + offset, PAGE_SIZE - offset); |
| |
| /* chain first in list head */ |
| first->private = (unsigned long)list; |
| err = virtqueue_add_buf_gfp(vi->rvq, vi->rx_sg, 0, MAX_SKB_FRAGS + 2, |
| first, gfp); |
| if (err < 0) |
| give_pages(vi, first); |
| |
| return err; |
| } |
| |
| static int add_recvbuf_mergeable(struct virtnet_info *vi, gfp_t gfp) |
| { |
| struct page *page; |
| int err; |
| |
| page = get_a_page(vi, gfp); |
| if (!page) |
| return -ENOMEM; |
| |
| sg_init_one(vi->rx_sg, page_address(page), PAGE_SIZE); |
| |
| err = virtqueue_add_buf_gfp(vi->rvq, vi->rx_sg, 0, 1, page, gfp); |
| if (err < 0) |
| give_pages(vi, page); |
| |
| return err; |
| } |
| |
| /* Returns false if we couldn't fill entirely (OOM). */ |
| static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp) |
| { |
| int err; |
| bool oom; |
| |
| do { |
| if (vi->mergeable_rx_bufs) |
| err = add_recvbuf_mergeable(vi, gfp); |
| else if (vi->big_packets) |
| err = add_recvbuf_big(vi, gfp); |
| else |
| err = add_recvbuf_small(vi, gfp); |
| |
| oom = err == -ENOMEM; |
| if (err < 0) |
| break; |
| ++vi->num; |
| } while (err > 0); |
| if (unlikely(vi->num > vi->max)) |
| vi->max = vi->num; |
| virtqueue_kick(vi->rvq); |
| return !oom; |
| } |
| |
| static void skb_recv_done(struct virtqueue *rvq) |
| { |
| struct virtnet_info *vi = rvq->vdev->priv; |
| /* Schedule NAPI, Suppress further interrupts if successful. */ |
| if (napi_schedule_prep(&vi->napi)) { |
| virtqueue_disable_cb(rvq); |
| __napi_schedule(&vi->napi); |
| } |
| } |
| |
| static void virtnet_napi_enable(struct virtnet_info *vi) |
| { |
| 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); |
| } |
| } |
| |
| static void refill_work(struct work_struct *work) |
| { |
| struct virtnet_info *vi; |
| bool still_empty; |
| |
| vi = container_of(work, struct virtnet_info, refill.work); |
| napi_disable(&vi->napi); |
| still_empty = !try_fill_recv(vi, GFP_KERNEL); |
| virtnet_napi_enable(vi); |
| |
| /* In theory, this can happen: if we don't get any buffers in |
| * we will *never* try to fill again. */ |
| if (still_empty) |
| schedule_delayed_work(&vi->refill, HZ/2); |
| } |
| |
| static int virtnet_poll(struct napi_struct *napi, int budget) |
| { |
| struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi); |
| void *buf; |
| unsigned int len, received = 0; |
| |
| again: |
| while (received < budget && |
| (buf = virtqueue_get_buf(vi->rvq, &len)) != NULL) { |
| receive_buf(vi->dev, buf, len); |
| --vi->num; |
| received++; |
| } |
| |
| if (vi->num < vi->max / 2) { |
| if (!try_fill_recv(vi, GFP_ATOMIC)) |
| schedule_delayed_work(&vi->refill, 0); |
| } |
| |
| /* Out of packets? */ |
| if (received < budget) { |
| napi_complete(napi); |
| if (unlikely(!virtqueue_enable_cb(vi->rvq)) && |
| napi_schedule_prep(napi)) { |
| virtqueue_disable_cb(vi->rvq); |
| __napi_schedule(napi); |
| goto again; |
| } |
| } |
| |
| return received; |
| } |
| |
| static unsigned int free_old_xmit_skbs(struct virtnet_info *vi) |
| { |
| struct sk_buff *skb; |
| unsigned int len, tot_sgs = 0; |
| struct virtnet_stats __percpu *stats = this_cpu_ptr(vi->stats); |
| |
| while ((skb = virtqueue_get_buf(vi->svq, &len)) != NULL) { |
| pr_debug("Sent skb %p\n", skb); |
| |
| u64_stats_update_begin(&stats->syncp); |
| stats->tx_bytes += skb->len; |
| stats->tx_packets++; |
| u64_stats_update_end(&stats->syncp); |
| |
| tot_sgs += skb_vnet_hdr(skb)->num_sg; |
| dev_kfree_skb_any(skb); |
| } |
| return tot_sgs; |
| } |
| |
| static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb) |
| { |
| 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_delayed(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; |
| } |
| |
| static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev, |
| struct rtnl_link_stats64 *tot) |
| { |
| struct virtnet_info *vi = netdev_priv(dev); |
| int cpu; |
| unsigned int start; |
| |
| for_each_possible_cpu(cpu) { |
| struct virtnet_stats __percpu *stats |
| = per_cpu_ptr(vi->stats, cpu); |
| u64 tpackets, tbytes, rpackets, rbytes; |
| |
| do { |
| start = u64_stats_fetch_begin(&stats->syncp); |
| tpackets = stats->tx_packets; |
| tbytes = stats->tx_bytes; |
| rpackets = stats->rx_packets; |
| rbytes = stats->rx_bytes; |
| } while (u64_stats_fetch_retry(&stats->syncp, start)); |
| |
| tot->rx_packets += rpackets; |
| tot->tx_packets += tpackets; |
| tot->rx_bytes += rbytes; |
| tot->tx_bytes += tbytes; |
| } |
| |
| tot->tx_dropped = dev->stats.tx_dropped; |
| tot->rx_dropped = dev->stats.rx_dropped; |
| tot->rx_length_errors = dev->stats.rx_length_errors; |
| tot->rx_frame_errors = dev->stats.rx_frame_errors; |
| |
| return tot; |
| } |
| |
| #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); |
| |
| virtnet_napi_enable(vi); |
| 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 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 void virtnet_get_ringparam(struct net_device *dev, |
| struct ethtool_ringparam *ring) |
| { |
| struct virtnet_info *vi = netdev_priv(dev); |
| |
| ring->rx_max_pending = virtqueue_get_vring_size(vi->rvq); |
| ring->tx_max_pending = virtqueue_get_vring_size(vi->svq); |
| ring->rx_pending = ring->rx_max_pending; |
| ring->tx_pending = ring->tx_max_pending; |
| |
| } |
| |
| |
| static void virtnet_get_drvinfo(struct net_device *dev, |
| struct ethtool_drvinfo *info) |
| { |
| struct virtnet_info *vi = netdev_priv(dev); |
| struct virtio_device *vdev = vi->vdev; |
| |
| strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver)); |
| strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version)); |
| strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info)); |
| |
| } |
| |
| static const struct ethtool_ops virtnet_ethtool_ops = { |
| .get_drvinfo = virtnet_get_drvinfo, |
| .get_link = ethtool_op_get_link, |
| .get_ringparam = virtnet_get_ringparam, |
| }; |
| |
| #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_get_stats64 = virtnet_stats, |
| .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_config_val(vi->vdev, VIRTIO_NET_F_STATUS, |
| offsetof(struct virtio_net_config, status), |
| &v) < 0) |
| return; |
| |
| /* 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->priv_flags |= IFF_UNICAST_FLT; |
| 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 (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) { |
| /* This opens up the world of extra features. */ |
| dev->hw_features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; |
| if (csum) |
| dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; |
| |
| if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) { |
| dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO |
| | NETIF_F_TSO_ECN | NETIF_F_TSO6; |
| } |
| /* Individual feature bits: what can host handle? */ |
| if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4)) |
| dev->hw_features |= NETIF_F_TSO; |
| if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6)) |
| dev->hw_features |= NETIF_F_TSO6; |
| if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN)) |
| dev->hw_features |= NETIF_F_TSO_ECN; |
| if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO)) |
| dev->hw_features |= NETIF_F_UFO; |
| |
| if (gso) |
| dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO); |
| /* (!csum && gso) case will be fixed by register_netdev() */ |
| } |
| |
| /* Configuration may specify what MAC to use. Otherwise random. */ |
| if (virtio_config_val_len(vdev, VIRTIO_NET_F_MAC, |
| offsetof(struct virtio_net_config, mac), |
| dev->dev_addr, dev->addr_len) < 0) |
| 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; |
| vi->stats = alloc_percpu(struct virtnet_stats); |
| err = -ENOMEM; |
| if (vi->stats == NULL) |
| goto free; |
| |
| 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_stats; |
| |
| 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_stats: |
| free_percpu(vi->stats); |
| 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_percpu(vi->stats); |
| 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"); |