/* A network driver using virtio. * * Copyright 2007 Rusty Russell 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, see . */ //#define DEBUG #include #include #include #include #include #include #include #include #include #include static int napi_weight = NAPI_POLL_WEIGHT; module_param(napi_weight, int, 0444); static bool csum = true, gso = true; module_param(csum, bool, 0444); module_param(gso, bool, 0444); /* FIXME: MTU in config. */ #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) #define MERGE_BUFFER_LEN (ALIGN(GOOD_PACKET_LEN + \ sizeof(struct virtio_net_hdr_mrg_rxbuf), \ L1_CACHE_BYTES)) #define GOOD_COPY_LEN 128 #define VIRTNET_DRIVER_VERSION "1.0.0" struct virtnet_stats { struct u64_stats_sync tx_syncp; struct u64_stats_sync rx_syncp; u64 tx_bytes; u64 tx_packets; u64 rx_bytes; u64 rx_packets; }; /* Internal representation of a send virtqueue */ struct send_queue { /* Virtqueue associated with this send _queue */ struct virtqueue *vq; /* TX: fragments + linear part + virtio header */ struct scatterlist sg[MAX_SKB_FRAGS + 2]; /* Name of the send queue: output.$index */ char name[40]; }; /* Internal representation of a receive virtqueue */ struct receive_queue { /* Virtqueue associated with this receive_queue */ struct virtqueue *vq; struct napi_struct napi; /* Number of input buffers, and max we've ever had. */ unsigned int num, max; /* Chain pages by the private ptr. */ struct page *pages; /* RX: fragments + linear part + virtio header */ struct scatterlist sg[MAX_SKB_FRAGS + 2]; /* Name of this receive queue: input.$index */ char name[40]; }; struct virtnet_info { struct virtio_device *vdev; struct virtqueue *cvq; struct net_device *dev; struct send_queue *sq; struct receive_queue *rq; unsigned int status; /* Max # of queue pairs supported by the device */ u16 max_queue_pairs; /* # of queue pairs currently used by the driver */ u16 curr_queue_pairs; /* 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; /* Has control virtqueue */ bool has_cvq; /* Host can handle any s/g split between our header and packet data */ bool any_header_sg; /* enable config space updates */ bool config_enable; /* Active statistics */ struct virtnet_stats __percpu *stats; /* Work struct for refilling if we run low on memory. */ struct delayed_work refill; /* Work struct for config space updates */ struct work_struct config_work; /* Lock for config space updates */ struct mutex config_lock; /* Page_frag for GFP_KERNEL packet buffer allocation when we run * low on memory. */ struct page_frag alloc_frag; /* Does the affinity hint is set for virtqueues? */ bool affinity_hint_set; /* CPU hot plug notifier */ struct notifier_block nb; }; struct skb_vnet_hdr { union { struct virtio_net_hdr hdr; struct virtio_net_hdr_mrg_rxbuf mhdr; }; }; 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]; }; /* Converting between virtqueue no. and kernel tx/rx queue no. * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq */ static int vq2txq(struct virtqueue *vq) { return (vq->index - 1) / 2; } static int txq2vq(int txq) { return txq * 2 + 1; } static int vq2rxq(struct virtqueue *vq) { return vq->index / 2; } static int rxq2vq(int rxq) { return rxq * 2; } 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 receive_queue *rq, struct page *page) { struct page *end; /* Find end of list, sew whole thing into vi->rq.pages. */ for (end = page; end->private; end = (struct page *)end->private); end->private = (unsigned long)rq->pages; rq->pages = page; } static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask) { struct page *p = rq->pages; if (p) { rq->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 *vq) { struct virtnet_info *vi = vq->vdev->priv; /* Suppress further interrupts. */ virtqueue_disable_cb(vq); /* We were probably waiting for more output buffers. */ netif_wake_subqueue(vi->dev, vq2txq(vq)); } /* Called from bottom half context */ static struct sk_buff *page_to_skb(struct receive_queue *rq, struct page *page, unsigned int offset, unsigned int len, unsigned int truesize) { struct virtnet_info *vi = rq->vq->vdev->priv; struct sk_buff *skb; struct skb_vnet_hdr *hdr; unsigned int copy, hdr_len, hdr_padded_len; char *p; p = page_address(page) + offset; /* 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; hdr_padded_len = sizeof hdr->mhdr; } else { hdr_len = sizeof hdr->hdr; hdr_padded_len = sizeof(struct padded_vnet_hdr); } memcpy(hdr, p, hdr_len); len -= hdr_len; offset += hdr_padded_len; p += hdr_padded_len; copy = len; if (copy > skb_tailroom(skb)) copy = skb_tailroom(skb); memcpy(skb_put(skb, copy), p, copy); len -= copy; offset += copy; if (vi->mergeable_rx_bufs) { if (len) skb_add_rx_frag(skb, 0, page, offset, len, truesize); else put_page(page); return skb; } /* * 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)) { net_dbg_ratelimited("%s: too much data\n", skb->dev->name); dev_kfree_skb(skb); return NULL; } BUG_ON(offset >= PAGE_SIZE); while (len) { unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len); skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset, frag_size, truesize); len -= frag_size; page = (struct page *)page->private; offset = 0; } if (page) give_pages(rq, page); return skb; } static struct sk_buff *receive_small(void *buf, unsigned int len) { struct sk_buff * skb = buf; len -= sizeof(struct virtio_net_hdr); skb_trim(skb, len); return skb; } static struct sk_buff *receive_big(struct net_device *dev, struct receive_queue *rq, void *buf, unsigned int len) { struct page *page = buf; struct sk_buff *skb = page_to_skb(rq, page, 0, len, PAGE_SIZE); if (unlikely(!skb)) goto err; return skb; err: dev->stats.rx_dropped++; give_pages(rq, page); return NULL; } static struct sk_buff *receive_mergeable(struct net_device *dev, struct receive_queue *rq, void *buf, unsigned int len) { struct skb_vnet_hdr *hdr = buf; int num_buf = hdr->mhdr.num_buffers; struct page *page = virt_to_head_page(buf); int offset = buf - page_address(page); struct sk_buff *head_skb = page_to_skb(rq, page, offset, len, MERGE_BUFFER_LEN); struct sk_buff *curr_skb = head_skb; if (unlikely(!curr_skb)) goto err_skb; while (--num_buf) { int num_skb_frags; buf = virtqueue_get_buf(rq->vq, &len); if (unlikely(!buf)) { pr_debug("%s: rx error: %d buffers out of %d missing\n", dev->name, num_buf, hdr->mhdr.num_buffers); dev->stats.rx_length_errors++; goto err_buf; } if (unlikely(len > MERGE_BUFFER_LEN)) { pr_debug("%s: rx error: merge buffer too long\n", dev->name); len = MERGE_BUFFER_LEN; } page = virt_to_head_page(buf); --rq->num; num_skb_frags = skb_shinfo(curr_skb)->nr_frags; if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) { struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC); if (unlikely(!nskb)) goto err_skb; if (curr_skb == head_skb) skb_shinfo(curr_skb)->frag_list = nskb; else curr_skb->next = nskb; curr_skb = nskb; head_skb->truesize += nskb->truesize; num_skb_frags = 0; } if (curr_skb != head_skb) { head_skb->data_len += len; head_skb->len += len; head_skb->truesize += MERGE_BUFFER_LEN; } offset = buf - page_address(page); if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) { put_page(page); skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1, len, MERGE_BUFFER_LEN); } else { skb_add_rx_frag(curr_skb, num_skb_frags, page, offset, len, MERGE_BUFFER_LEN); } } return head_skb; err_skb: put_page(page); while (--num_buf) { buf = virtqueue_get_buf(rq->vq, &len); if (unlikely(!buf)) { pr_debug("%s: rx error: %d buffers missing\n", dev->name, num_buf); dev->stats.rx_length_errors++; break; } page = virt_to_head_page(buf); put_page(page); --rq->num; } err_buf: dev->stats.rx_dropped++; dev_kfree_skb(head_skb); return NULL; } static void receive_buf(struct receive_queue *rq, void *buf, unsigned int len) { struct virtnet_info *vi = rq->vq->vdev->priv; struct net_device *dev = vi->dev; struct virtnet_stats *stats = this_cpu_ptr(vi->stats); struct sk_buff *skb; 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) put_page(virt_to_head_page(buf)); else if (vi->big_packets) give_pages(rq, buf); else dev_kfree_skb(buf); return; } if (vi->mergeable_rx_bufs) skb = receive_mergeable(dev, rq, buf, len); else if (vi->big_packets) skb = receive_big(dev, rq, buf, len); else skb = receive_small(buf, len); if (unlikely(!skb)) return; hdr = skb_vnet_hdr(skb); u64_stats_update_begin(&stats->rx_syncp); stats->rx_bytes += skb->len; stats->rx_packets++; u64_stats_update_end(&stats->rx_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: net_warn_ratelimited("%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) { net_warn_ratelimited("%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 receive_queue *rq, gfp_t gfp) { struct virtnet_info *vi = rq->vq->vdev->priv; struct sk_buff *skb; struct skb_vnet_hdr *hdr; int err; skb = __netdev_alloc_skb_ip_align(vi->dev, GOOD_PACKET_LEN, gfp); if (unlikely(!skb)) return -ENOMEM; skb_put(skb, GOOD_PACKET_LEN); hdr = skb_vnet_hdr(skb); sg_set_buf(rq->sg, &hdr->hdr, sizeof hdr->hdr); skb_to_sgvec(skb, rq->sg + 1, 0, skb->len); err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp); if (err < 0) dev_kfree_skb(skb); return err; } static int add_recvbuf_big(struct receive_queue *rq, gfp_t gfp) { struct page *first, *list = NULL; char *p; int i, err, offset; /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */ for (i = MAX_SKB_FRAGS + 1; i > 1; --i) { first = get_a_page(rq, gfp); if (!first) { if (list) give_pages(rq, list); return -ENOMEM; } sg_set_buf(&rq->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(rq, gfp); if (!first) { give_pages(rq, list); return -ENOMEM; } p = page_address(first); /* rq->sg[0], rq->sg[1] share the same page */ /* a separated rq->sg[0] for virtio_net_hdr only due to QEMU bug */ sg_set_buf(&rq->sg[0], p, sizeof(struct virtio_net_hdr)); /* rq->sg[1] for data packet, from offset */ offset = sizeof(struct padded_vnet_hdr); sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset); /* chain first in list head */ first->private = (unsigned long)list; err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2, first, gfp); if (err < 0) give_pages(rq, first); return err; } static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp) { struct virtnet_info *vi = rq->vq->vdev->priv; char *buf = NULL; int err; if (gfp & __GFP_WAIT) { if (skb_page_frag_refill(MERGE_BUFFER_LEN, &vi->alloc_frag, gfp)) { buf = (char *)page_address(vi->alloc_frag.page) + vi->alloc_frag.offset; get_page(vi->alloc_frag.page); vi->alloc_frag.offset += MERGE_BUFFER_LEN; } } else { buf = netdev_alloc_frag(MERGE_BUFFER_LEN); } if (!buf) return -ENOMEM; sg_init_one(rq->sg, buf, MERGE_BUFFER_LEN); err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, buf, gfp); if (err < 0) put_page(virt_to_head_page(buf)); return err; } /* * Returns false if we couldn't fill entirely (OOM). * * Normally run in the receive path, but can also be run from ndo_open * before we're receiving packets, or from refill_work which is * careful to disable receiving (using napi_disable). */ static bool try_fill_recv(struct receive_queue *rq, gfp_t gfp) { struct virtnet_info *vi = rq->vq->vdev->priv; int err; bool oom; do { if (vi->mergeable_rx_bufs) err = add_recvbuf_mergeable(rq, gfp); else if (vi->big_packets) err = add_recvbuf_big(rq, gfp); else err = add_recvbuf_small(rq, gfp); oom = err == -ENOMEM; if (err) break; ++rq->num; } while (rq->vq->num_free); if (unlikely(rq->num > rq->max)) rq->max = rq->num; if (unlikely(!virtqueue_kick(rq->vq))) return false; return !oom; } static void skb_recv_done(struct virtqueue *rvq) { struct virtnet_info *vi = rvq->vdev->priv; struct receive_queue *rq = &vi->rq[vq2rxq(rvq)]; /* Schedule NAPI, Suppress further interrupts if successful. */ if (napi_schedule_prep(&rq->napi)) { virtqueue_disable_cb(rvq); __napi_schedule(&rq->napi); } } static void virtnet_napi_enable(struct receive_queue *rq) { napi_enable(&rq->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(&rq->napi)) { virtqueue_disable_cb(rq->vq); local_bh_disable(); __napi_schedule(&rq->napi); local_bh_enable(); } } static void refill_work(struct work_struct *work) { struct virtnet_info *vi = container_of(work, struct virtnet_info, refill.work); bool still_empty; int i; for (i = 0; i < vi->curr_queue_pairs; i++) { struct receive_queue *rq = &vi->rq[i]; napi_disable(&rq->napi); still_empty = !try_fill_recv(rq, GFP_KERNEL); virtnet_napi_enable(rq); /* 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 receive_queue *rq = container_of(napi, struct receive_queue, napi); struct virtnet_info *vi = rq->vq->vdev->priv; void *buf; unsigned int r, len, received = 0; again: while (received < budget && (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) { receive_buf(rq, buf, len); --rq->num; received++; } if (rq->num < rq->max / 2) { if (!try_fill_recv(rq, GFP_ATOMIC)) schedule_delayed_work(&vi->refill, 0); } /* Out of packets? */ if (received < budget) { r = virtqueue_enable_cb_prepare(rq->vq); napi_complete(napi); if (unlikely(virtqueue_poll(rq->vq, r)) && napi_schedule_prep(napi)) { virtqueue_disable_cb(rq->vq); __napi_schedule(napi); goto again; } } return received; } static int virtnet_open(struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); int i; for (i = 0; i < vi->max_queue_pairs; i++) { if (i < vi->curr_queue_pairs) /* Make sure we have some buffers: if oom use wq. */ if (!try_fill_recv(&vi->rq[i], GFP_KERNEL)) schedule_delayed_work(&vi->refill, 0); virtnet_napi_enable(&vi->rq[i]); } return 0; } static void free_old_xmit_skbs(struct send_queue *sq) { struct sk_buff *skb; unsigned int len; struct virtnet_info *vi = sq->vq->vdev->priv; struct virtnet_stats *stats = this_cpu_ptr(vi->stats); while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) { pr_debug("Sent skb %p\n", skb); u64_stats_update_begin(&stats->tx_syncp); stats->tx_bytes += skb->len; stats->tx_packets++; u64_stats_update_end(&stats->tx_syncp); dev_kfree_skb_any(skb); } } static int xmit_skb(struct send_queue *sq, struct sk_buff *skb) { struct skb_vnet_hdr *hdr; const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest; struct virtnet_info *vi = sq->vq->vdev->priv; unsigned num_sg; unsigned hdr_len; bool can_push; pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest); if (vi->mergeable_rx_bufs) hdr_len = sizeof hdr->mhdr; else hdr_len = sizeof hdr->hdr; can_push = vi->any_header_sg && !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) && !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len; /* Even if we can, don't push here yet as this would skew * csum_start offset below. */ if (can_push) hdr = (struct skb_vnet_hdr *)(skb->data - hdr_len); else hdr = skb_vnet_hdr(skb); 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; } if (vi->mergeable_rx_bufs) hdr->mhdr.num_buffers = 0; if (can_push) { __skb_push(skb, hdr_len); num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len); /* Pull header back to avoid skew in tx bytes calculations. */ __skb_pull(skb, hdr_len); } else { sg_set_buf(sq->sg, hdr, hdr_len); num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1; } return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC); } static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); int qnum = skb_get_queue_mapping(skb); struct send_queue *sq = &vi->sq[qnum]; int err; /* Free up any pending old buffers before queueing new ones. */ free_old_xmit_skbs(sq); /* Try to transmit */ err = xmit_skb(sq, skb); /* This should not happen! */ if (unlikely(err) || unlikely(!virtqueue_kick(sq->vq))) { dev->stats.tx_fifo_errors++; if (net_ratelimit()) dev_warn(&dev->dev, "Unexpected TXQ (%d) queue failure: %d\n", qnum, err); dev->stats.tx_dropped++; kfree_skb(skb); return NETDEV_TX_OK; } /* 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 (sq->vq->num_free < 2+MAX_SKB_FRAGS) { netif_stop_subqueue(dev, qnum); if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) { /* More just got used, free them then recheck. */ free_old_xmit_skbs(sq); if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) { netif_start_subqueue(dev, qnum); virtqueue_disable_cb(sq->vq); } } } return NETDEV_TX_OK; } /* * 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 *out, struct scatterlist *in) { struct scatterlist *sgs[4], hdr, stat; struct virtio_net_ctrl_hdr ctrl; virtio_net_ctrl_ack status = ~0; unsigned out_num = 0, in_num = 0, tmp; /* Caller should know better */ BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)); ctrl.class = class; ctrl.cmd = cmd; /* Add header */ sg_init_one(&hdr, &ctrl, sizeof(ctrl)); sgs[out_num++] = &hdr; if (out) sgs[out_num++] = out; if (in) sgs[out_num + in_num++] = in; /* Add return status. */ sg_init_one(&stat, &status, sizeof(status)); sgs[out_num + in_num++] = &stat; BUG_ON(out_num + in_num > ARRAY_SIZE(sgs)); BUG_ON(virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC) < 0); if (unlikely(!virtqueue_kick(vi->cvq))) return status == VIRTIO_NET_OK; /* 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) && !virtqueue_is_broken(vi->cvq)) cpu_relax(); return status == VIRTIO_NET_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; struct sockaddr *addr = p; struct scatterlist sg; ret = eth_prepare_mac_addr_change(dev, p); if (ret) return ret; if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { sg_init_one(&sg, addr->sa_data, dev->addr_len); if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg, NULL)) { dev_warn(&vdev->dev, "Failed to set mac address by vq command.\n"); return -EINVAL; } } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) { unsigned int i; /* Naturally, this has an atomicity problem. */ for (i = 0; i < dev->addr_len; i++) virtio_cwrite8(vdev, offsetof(struct virtio_net_config, mac) + i, addr->sa_data[i]); } eth_commit_mac_addr_change(dev, p); 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 *stats = per_cpu_ptr(vi->stats, cpu); u64 tpackets, tbytes, rpackets, rbytes; do { start = u64_stats_fetch_begin_bh(&stats->tx_syncp); tpackets = stats->tx_packets; tbytes = stats->tx_bytes; } while (u64_stats_fetch_retry_bh(&stats->tx_syncp, start)); do { start = u64_stats_fetch_begin_bh(&stats->rx_syncp); rpackets = stats->rx_packets; rbytes = stats->rx_bytes; } while (u64_stats_fetch_retry_bh(&stats->rx_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->tx_fifo_errors = dev->stats.tx_fifo_errors; 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); int i; for (i = 0; i < vi->curr_queue_pairs; i++) napi_schedule(&vi->rq[i].napi); } #endif static void virtnet_ack_link_announce(struct virtnet_info *vi) { rtnl_lock(); if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE, VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL, NULL)) dev_warn(&vi->dev->dev, "Failed to ack link announce.\n"); rtnl_unlock(); } static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs) { struct scatterlist sg; struct virtio_net_ctrl_mq s; struct net_device *dev = vi->dev; if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ)) return 0; s.virtqueue_pairs = queue_pairs; sg_init_one(&sg, &s, sizeof(s)); if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ, VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg, NULL)) { dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n", queue_pairs); return -EINVAL; } else { vi->curr_queue_pairs = queue_pairs; /* virtnet_open() will refill when device is going to up. */ if (dev->flags & IFF_UP) schedule_delayed_work(&vi->refill, 0); } return 0; } static int virtnet_close(struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); int i; /* Make sure refill_work doesn't re-enable napi! */ cancel_delayed_work_sync(&vi->refill); for (i = 0; i < vi->max_queue_pairs; i++) napi_disable(&vi->rq[i].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, NULL)) 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, NULL)) 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) 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, NULL)) dev_warn(&dev->dev, "Failed to set MAC filter table.\n"); kfree(buf); } static int virtnet_vlan_rx_add_vid(struct net_device *dev, __be16 proto, 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, NULL)) dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid); return 0; } static int virtnet_vlan_rx_kill_vid(struct net_device *dev, __be16 proto, 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, NULL)) dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid); return 0; } static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu) { int i; if (vi->affinity_hint_set) { for (i = 0; i < vi->max_queue_pairs; i++) { virtqueue_set_affinity(vi->rq[i].vq, -1); virtqueue_set_affinity(vi->sq[i].vq, -1); } vi->affinity_hint_set = false; } } static void virtnet_set_affinity(struct virtnet_info *vi) { int i; int cpu; /* In multiqueue mode, when the number of cpu is equal to the number of * queue pairs, we let the queue pairs to be private to one cpu by * setting the affinity hint to eliminate the contention. */ if (vi->curr_queue_pairs == 1 || vi->max_queue_pairs != num_online_cpus()) { virtnet_clean_affinity(vi, -1); return; } i = 0; for_each_online_cpu(cpu) { virtqueue_set_affinity(vi->rq[i].vq, cpu); virtqueue_set_affinity(vi->sq[i].vq, cpu); netif_set_xps_queue(vi->dev, cpumask_of(cpu), i); i++; } vi->affinity_hint_set = true; } static int virtnet_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { struct virtnet_info *vi = container_of(nfb, struct virtnet_info, nb); switch(action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: case CPU_DOWN_FAILED: case CPU_DEAD: virtnet_set_affinity(vi); break; case CPU_DOWN_PREPARE: virtnet_clean_affinity(vi, (long)hcpu); break; default: break; } return NOTIFY_OK; } 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->rq[0].vq); ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq); 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)); } /* TODO: Eliminate OOO packets during switching */ static int virtnet_set_channels(struct net_device *dev, struct ethtool_channels *channels) { struct virtnet_info *vi = netdev_priv(dev); u16 queue_pairs = channels->combined_count; int err; /* We don't support separate rx/tx channels. * We don't allow setting 'other' channels. */ if (channels->rx_count || channels->tx_count || channels->other_count) return -EINVAL; if (queue_pairs > vi->max_queue_pairs) return -EINVAL; get_online_cpus(); err = virtnet_set_queues(vi, queue_pairs); if (!err) { netif_set_real_num_tx_queues(dev, queue_pairs); netif_set_real_num_rx_queues(dev, queue_pairs); virtnet_set_affinity(vi); } put_online_cpus(); return err; } static void virtnet_get_channels(struct net_device *dev, struct ethtool_channels *channels) { struct virtnet_info *vi = netdev_priv(dev); channels->combined_count = vi->curr_queue_pairs; channels->max_combined = vi->max_queue_pairs; channels->max_other = 0; channels->rx_count = 0; channels->tx_count = 0; channels->other_count = 0; } static const struct ethtool_ops virtnet_ethtool_ops = { .get_drvinfo = virtnet_get_drvinfo, .get_link = ethtool_op_get_link, .get_ringparam = virtnet_get_ringparam, .set_channels = virtnet_set_channels, .get_channels = virtnet_get_channels, }; #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_config_changed_work(struct work_struct *work) { struct virtnet_info *vi = container_of(work, struct virtnet_info, config_work); u16 v; mutex_lock(&vi->config_lock); if (!vi->config_enable) goto done; if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS, struct virtio_net_config, status, &v) < 0) goto done; if (v & VIRTIO_NET_S_ANNOUNCE) { netdev_notify_peers(vi->dev); virtnet_ack_link_announce(vi); } /* Ignore unknown (future) status bits */ v &= VIRTIO_NET_S_LINK_UP; if (vi->status == v) goto done; vi->status = v; if (vi->status & VIRTIO_NET_S_LINK_UP) { netif_carrier_on(vi->dev); netif_tx_wake_all_queues(vi->dev); } else { netif_carrier_off(vi->dev); netif_tx_stop_all_queues(vi->dev); } done: mutex_unlock(&vi->config_lock); } static void virtnet_config_changed(struct virtio_device *vdev) { struct virtnet_info *vi = vdev->priv; schedule_work(&vi->config_work); } static void virtnet_free_queues(struct virtnet_info *vi) { int i; for (i = 0; i < vi->max_queue_pairs; i++) netif_napi_del(&vi->rq[i].napi); kfree(vi->rq); kfree(vi->sq); } static void free_receive_bufs(struct virtnet_info *vi) { int i; for (i = 0; i < vi->max_queue_pairs; i++) { while (vi->rq[i].pages) __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0); } } static void free_unused_bufs(struct virtnet_info *vi) { void *buf; int i; for (i = 0; i < vi->max_queue_pairs; i++) { struct virtqueue *vq = vi->sq[i].vq; while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) dev_kfree_skb(buf); } for (i = 0; i < vi->max_queue_pairs; i++) { struct virtqueue *vq = vi->rq[i].vq; while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) { if (vi->mergeable_rx_bufs) put_page(virt_to_head_page(buf)); else if (vi->big_packets) give_pages(&vi->rq[i], buf); else dev_kfree_skb(buf); --vi->rq[i].num; } BUG_ON(vi->rq[i].num != 0); } } static void virtnet_del_vqs(struct virtnet_info *vi) { struct virtio_device *vdev = vi->vdev; virtnet_clean_affinity(vi, -1); vdev->config->del_vqs(vdev); virtnet_free_queues(vi); } static int virtnet_find_vqs(struct virtnet_info *vi) { vq_callback_t **callbacks; struct virtqueue **vqs; int ret = -ENOMEM; int i, total_vqs; const char **names; /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by * possible control vq. */ total_vqs = vi->max_queue_pairs * 2 + virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ); /* Allocate space for find_vqs parameters */ vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL); if (!vqs) goto err_vq; callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL); if (!callbacks) goto err_callback; names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL); if (!names) goto err_names; /* Parameters for control virtqueue, if any */ if (vi->has_cvq) { callbacks[total_vqs - 1] = NULL; names[total_vqs - 1] = "control"; } /* Allocate/initialize parameters for send/receive virtqueues */ for (i = 0; i < vi->max_queue_pairs; i++) { callbacks[rxq2vq(i)] = skb_recv_done; callbacks[txq2vq(i)] = skb_xmit_done; sprintf(vi->rq[i].name, "input.%d", i); sprintf(vi->sq[i].name, "output.%d", i); names[rxq2vq(i)] = vi->rq[i].name; names[txq2vq(i)] = vi->sq[i].name; } ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks, names); if (ret) goto err_find; if (vi->has_cvq) { vi->cvq = vqs[total_vqs - 1]; if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN)) vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER; } for (i = 0; i < vi->max_queue_pairs; i++) { vi->rq[i].vq = vqs[rxq2vq(i)]; vi->sq[i].vq = vqs[txq2vq(i)]; } kfree(names); kfree(callbacks); kfree(vqs); return 0; err_find: kfree(names); err_names: kfree(callbacks); err_callback: kfree(vqs); err_vq: return ret; } static int virtnet_alloc_queues(struct virtnet_info *vi) { int i; vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL); if (!vi->sq) goto err_sq; vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL); if (!vi->rq) goto err_rq; INIT_DELAYED_WORK(&vi->refill, refill_work); for (i = 0; i < vi->max_queue_pairs; i++) { vi->rq[i].pages = NULL; netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll, napi_weight); sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg)); sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg)); } return 0; err_rq: kfree(vi->sq); err_sq: return -ENOMEM; } static int init_vqs(struct virtnet_info *vi) { int ret; /* Allocate send & receive queues */ ret = virtnet_alloc_queues(vi); if (ret) goto err; ret = virtnet_find_vqs(vi); if (ret) goto err_free; get_online_cpus(); virtnet_set_affinity(vi); put_online_cpus(); return 0; err_free: virtnet_free_queues(vi); err: return ret; } static int virtnet_probe(struct virtio_device *vdev) { int i, err; struct net_device *dev; struct virtnet_info *vi; u16 max_queue_pairs; /* Find if host supports multiqueue virtio_net device */ err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ, struct virtio_net_config, max_virtqueue_pairs, &max_queue_pairs); /* We need at least 2 queue's */ if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN || max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX || !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) max_queue_pairs = 1; /* Allocate ourselves a network device with room for our info */ dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs); if (!dev) return -ENOMEM; /* Set up network device as normal. */ dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE; 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() */ } if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM)) dev->features |= NETIF_F_RXCSUM; dev->vlan_features = dev->features; /* Configuration may specify what MAC to use. Otherwise random. */ if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) virtio_cread_bytes(vdev, offsetof(struct virtio_net_config, mac), dev->dev_addr, dev->addr_len); else eth_hw_addr_random(dev); /* Set up our device-specific information */ vi = netdev_priv(dev); vi->dev = dev; vi->vdev = vdev; vdev->priv = vi; vi->stats = alloc_percpu(struct virtnet_stats); err = -ENOMEM; if (vi->stats == NULL) goto free; for_each_possible_cpu(i) { struct virtnet_stats *virtnet_stats; virtnet_stats = per_cpu_ptr(vi->stats, i); u64_stats_init(&virtnet_stats->tx_syncp); u64_stats_init(&virtnet_stats->rx_syncp); } mutex_init(&vi->config_lock); vi->config_enable = true; INIT_WORK(&vi->config_work, virtnet_config_changed_work); /* 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; if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT)) vi->any_header_sg = true; if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) vi->has_cvq = true; /* Use single tx/rx queue pair as default */ vi->curr_queue_pairs = 1; vi->max_queue_pairs = max_queue_pairs; /* Allocate/initialize the rx/tx queues, and invoke find_vqs */ err = init_vqs(vi); if (err) goto free_stats; netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs); netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs); 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. */ for (i = 0; i < vi->curr_queue_pairs; i++) { try_fill_recv(&vi->rq[i], GFP_KERNEL); /* If we didn't even get one input buffer, we're useless. */ if (vi->rq[i].num == 0) { free_unused_bufs(vi); err = -ENOMEM; goto free_recv_bufs; } } vi->nb.notifier_call = &virtnet_cpu_callback; err = register_hotcpu_notifier(&vi->nb); if (err) { pr_debug("virtio_net: registering cpu notifier failed\n"); goto free_recv_bufs; } /* 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); schedule_work(&vi->config_work); } else { vi->status = VIRTIO_NET_S_LINK_UP; netif_carrier_on(dev); } pr_debug("virtnet: registered device %s with %d RX and TX vq's\n", dev->name, max_queue_pairs); return 0; free_recv_bufs: free_receive_bufs(vi); unregister_netdev(dev); free_vqs: cancel_delayed_work_sync(&vi->refill); virtnet_del_vqs(vi); if (vi->alloc_frag.page) put_page(vi->alloc_frag.page); free_stats: free_percpu(vi->stats); free: free_netdev(dev); return err; } static void remove_vq_common(struct virtnet_info *vi) { vi->vdev->config->reset(vi->vdev); /* Free unused buffers in both send and recv, if any. */ free_unused_bufs(vi); free_receive_bufs(vi); virtnet_del_vqs(vi); } static void virtnet_remove(struct virtio_device *vdev) { struct virtnet_info *vi = vdev->priv; unregister_hotcpu_notifier(&vi->nb); /* Prevent config work handler from accessing the device. */ mutex_lock(&vi->config_lock); vi->config_enable = false; mutex_unlock(&vi->config_lock); unregister_netdev(vi->dev); remove_vq_common(vi); if (vi->alloc_frag.page) put_page(vi->alloc_frag.page); flush_work(&vi->config_work); free_percpu(vi->stats); free_netdev(vi->dev); } #ifdef CONFIG_PM_SLEEP static int virtnet_freeze(struct virtio_device *vdev) { struct virtnet_info *vi = vdev->priv; int i; unregister_hotcpu_notifier(&vi->nb); /* Prevent config work handler from accessing the device */ mutex_lock(&vi->config_lock); vi->config_enable = false; mutex_unlock(&vi->config_lock); netif_device_detach(vi->dev); cancel_delayed_work_sync(&vi->refill); if (netif_running(vi->dev)) for (i = 0; i < vi->max_queue_pairs; i++) { napi_disable(&vi->rq[i].napi); netif_napi_del(&vi->rq[i].napi); } remove_vq_common(vi); flush_work(&vi->config_work); return 0; } static int virtnet_restore(struct virtio_device *vdev) { struct virtnet_info *vi = vdev->priv; int err, i; err = init_vqs(vi); if (err) return err; if (netif_running(vi->dev)) for (i = 0; i < vi->max_queue_pairs; i++) virtnet_napi_enable(&vi->rq[i]); netif_device_attach(vi->dev); for (i = 0; i < vi->curr_queue_pairs; i++) if (!try_fill_recv(&vi->rq[i], GFP_KERNEL)) schedule_delayed_work(&vi->refill, 0); mutex_lock(&vi->config_lock); vi->config_enable = true; mutex_unlock(&vi->config_lock); rtnl_lock(); virtnet_set_queues(vi, vi->curr_queue_pairs); rtnl_unlock(); err = register_hotcpu_notifier(&vi->nb); if (err) return err; return 0; } #endif 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, VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, VIRTIO_NET_F_CTRL_MAC_ADDR, VIRTIO_F_ANY_LAYOUT, }; 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 = virtnet_remove, .config_changed = virtnet_config_changed, #ifdef CONFIG_PM_SLEEP .freeze = virtnet_freeze, .restore = virtnet_restore, #endif }; module_virtio_driver(virtio_net_driver); MODULE_DEVICE_TABLE(virtio, id_table); MODULE_DESCRIPTION("Virtio network driver"); MODULE_LICENSE("GPL");