From: Krishna Kumar <krkumar2@xxxxxxxxxx> Implement mq virtio-net driver. Though struct virtio_net_config changes, it works with the old qemu since the last element is not accessed unless qemu sets VIRTIO_NET_F_MULTIQUEUE. Signed-off-by: Krishna Kumar <krkumar2@xxxxxxxxxx> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> --- drivers/net/virtio_net.c | 578 +++++++++++++++++++++++++++++++------------- include/linux/virtio_net.h | 3 2 files changed, 411 insertions(+), 170 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 0c7321c..03a199d 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -49,16 +49,48 @@ struct virtnet_stats { u64 rx_packets; }; -struct virtnet_info { - struct virtio_device *vdev; - struct virtqueue *rvq, *svq, *cvq; - struct net_device *dev; +/* Internal representation of a send virtqueue */ +struct send_queue { + /* Virtqueue associated with this send _queue */ + struct virtqueue *svq; + + /* TX: fragments + linear part + virtio header */ + struct scatterlist tx_sg[MAX_SKB_FRAGS + 2]; +}; + +/* Internal representation of a receive virtqueue */ +struct receive_queue { + /* Virtqueue associated with this receive_queue */ + struct virtqueue *rvq; + + /* Back pointer to the virtnet_info */ + struct virtnet_info *vi; + struct napi_struct napi; - unsigned int status; /* Number of input buffers, and max we've ever had. */ unsigned int num, max; + /* Work struct for refilling if we run low on memory. */ + struct delayed_work refill; + + /* Chain pages by the private ptr. */ + struct page *pages; + + /* RX: fragments + linear part + virtio header */ + struct scatterlist rx_sg[MAX_SKB_FRAGS + 2]; +}; + +struct virtnet_info { + struct send_queue **sq; + struct receive_queue **rq; + + int numtxqs; /* # of rxqs/txqs */ + struct virtio_device *vdev; + struct virtqueue *cvq; + struct net_device *dev; + unsigned int status; + /* I like... big packets and I cannot lie! */ bool big_packets; @@ -67,16 +99,6 @@ struct virtnet_info { /* 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 { @@ -106,22 +128,22 @@ static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb) * 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) +static void give_pages(struct receive_queue *rq, 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; + end->private = (unsigned long)rq->pages; + rq->pages = page; } -static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask) +static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask) { - struct page *p = vi->pages; + struct page *p = rq->pages; if (p) { - vi->pages = (struct page *)p->private; + rq->pages = (struct page *)p->private; /* clear private here, it is used to chain pages */ p->private = 0; } else @@ -132,12 +154,13 @@ static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask) static void skb_xmit_done(struct virtqueue *svq) { struct virtnet_info *vi = svq->vdev->priv; + int qnum = svq->queue_index / 2; /* RX/TX vqs are allocated in pairs */ /* Suppress further interrupts. */ virtqueue_disable_cb(svq); /* We were probably waiting for more output buffers. */ - netif_wake_queue(vi->dev); + netif_wake_subqueue(vi->dev, qnum); } static void set_skb_frag(struct sk_buff *skb, struct page *page, @@ -157,9 +180,10 @@ static void set_skb_frag(struct sk_buff *skb, struct page *page, *len -= f->size; } -static struct sk_buff *page_to_skb(struct virtnet_info *vi, +static struct sk_buff *page_to_skb(struct receive_queue *rq, struct page *page, unsigned int len) { + struct virtnet_info *vi = rq->vi; struct sk_buff *skb; struct skb_vnet_hdr *hdr; unsigned int copy, hdr_len, offset; @@ -202,12 +226,12 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi, } if (page) - give_pages(vi, page); + give_pages(rq, page); return skb; } -static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb) +static int receive_mergeable(struct receive_queue *rq, struct sk_buff *skb) { struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb); struct page *page; @@ -221,7 +245,8 @@ static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb) skb->dev->stats.rx_length_errors++; return -EINVAL; } - page = virtqueue_get_buf(vi->rvq, &len); + + page = virtqueue_get_buf(rq->rvq, &len); if (!page) { pr_debug("%s: rx error: %d buffers missing\n", skb->dev->name, hdr->mhdr.num_buffers); @@ -234,13 +259,14 @@ static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb) set_skb_frag(skb, page, 0, &len); - --vi->num; + --rq->num; } return 0; } -static void receive_buf(struct net_device *dev, void *buf, unsigned int len) +static void receive_buf(struct receive_queue *rq, void *buf, unsigned int len) { + struct net_device *dev = rq->vi->dev; struct virtnet_info *vi = netdev_priv(dev); struct virtnet_stats __percpu *stats = this_cpu_ptr(vi->stats); struct sk_buff *skb; @@ -251,7 +277,7 @@ static void receive_buf(struct net_device *dev, void *buf, unsigned int len) 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); + give_pages(rq, buf); else dev_kfree_skb(buf); return; @@ -263,14 +289,14 @@ static void receive_buf(struct net_device *dev, void *buf, unsigned int len) skb_trim(skb, len); } else { page = buf; - skb = page_to_skb(vi, page, len); + skb = page_to_skb(rq, page, len); if (unlikely(!skb)) { dev->stats.rx_dropped++; - give_pages(vi, page); + give_pages(rq, page); return; } if (vi->mergeable_rx_bufs) - if (receive_mergeable(vi, skb)) { + if (receive_mergeable(rq, skb)) { dev_kfree_skb(skb); return; } @@ -341,184 +367,200 @@ frame_err: dev_kfree_skb(skb); } -static int add_recvbuf_small(struct virtnet_info *vi, gfp_t gfp) +static int add_recvbuf_small(struct receive_queue *rq, 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); + skb = netdev_alloc_skb_ip_align(rq->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); + sg_set_buf(rq->rx_sg, &hdr->hdr, sizeof hdr->hdr); - skb_to_sgvec(skb, vi->rx_sg + 1, 0, skb->len); + skb_to_sgvec(skb, rq->rx_sg + 1, 0, skb->len); - err = virtqueue_add_buf_gfp(vi->rvq, vi->rx_sg, 0, 2, skb, gfp); + err = virtqueue_add_buf_gfp(rq->rvq, rq->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) +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 vi->rx_sg[MAX_SKB_FRAGS + 1] is list tail */ + /* page in rq->rx_sg[MAX_SKB_FRAGS + 1] is list tail */ for (i = MAX_SKB_FRAGS + 1; i > 1; --i) { - first = get_a_page(vi, gfp); + first = get_a_page(rq, gfp); if (!first) { if (list) - give_pages(vi, list); + give_pages(rq, list); return -ENOMEM; } - sg_set_buf(&vi->rx_sg[i], page_address(first), PAGE_SIZE); + sg_set_buf(&rq->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); + first = get_a_page(rq, gfp); if (!first) { - give_pages(vi, list); + give_pages(rq, 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)); + /* rq->rx_sg[0], rq->rx_sg[1] share the same page */ + /* a separated rq->rx_sg[0] for virtio_net_hdr only due to QEMU bug */ + sg_set_buf(&rq->rx_sg[0], p, sizeof(struct virtio_net_hdr)); - /* vi->rx_sg[1] for data packet, from offset */ + /* rq->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); + sg_set_buf(&rq->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, + err = virtqueue_add_buf_gfp(rq->rvq, rq->rx_sg, 0, MAX_SKB_FRAGS + 2, first, gfp); if (err < 0) - give_pages(vi, first); + give_pages(rq, first); return err; } -static int add_recvbuf_mergeable(struct virtnet_info *vi, gfp_t gfp) +static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp) { struct page *page; int err; - page = get_a_page(vi, gfp); + page = get_a_page(rq, gfp); if (!page) return -ENOMEM; - sg_init_one(vi->rx_sg, page_address(page), PAGE_SIZE); + sg_init_one(rq->rx_sg, page_address(page), PAGE_SIZE); - err = virtqueue_add_buf_gfp(vi->rvq, vi->rx_sg, 0, 1, page, gfp); + err = virtqueue_add_buf_gfp(rq->rvq, rq->rx_sg, 0, 1, page, gfp); if (err < 0) - give_pages(vi, page); + give_pages(rq, page); return err; } /* Returns false if we couldn't fill entirely (OOM). */ -static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp) +static bool try_fill_recv(struct receive_queue *rq, gfp_t gfp) { + struct virtnet_info *vi = rq->vi; int err; bool oom; do { if (vi->mergeable_rx_bufs) - err = add_recvbuf_mergeable(vi, gfp); + err = add_recvbuf_mergeable(rq, gfp); else if (vi->big_packets) - err = add_recvbuf_big(vi, gfp); + err = add_recvbuf_big(rq, gfp); else - err = add_recvbuf_small(vi, gfp); + err = add_recvbuf_small(rq, gfp); oom = err == -ENOMEM; if (err < 0) break; - ++vi->num; + ++rq->num; } while (err > 0); - if (unlikely(vi->num > vi->max)) - vi->max = vi->num; - virtqueue_kick(vi->rvq); + if (unlikely(rq->num > rq->max)) + rq->max = rq->num; + virtqueue_kick(rq->rvq); return !oom; } static void skb_recv_done(struct virtqueue *rvq) { + int qnum = rvq->queue_index / 2; /* RX/TX vqs are allocated in pairs */ struct virtnet_info *vi = rvq->vdev->priv; + struct napi_struct *napi = &vi->rq[qnum]->napi; + /* Schedule NAPI, Suppress further interrupts if successful. */ - if (napi_schedule_prep(&vi->napi)) { + if (napi_schedule_prep(napi)) { virtqueue_disable_cb(rvq); - __napi_schedule(&vi->napi); + __napi_schedule(napi); } } -static void virtnet_napi_enable(struct virtnet_info *vi) +static void virtnet_napi_enable(struct receive_queue *rq) { - napi_enable(&vi->napi); + 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(&vi->napi)) { - virtqueue_disable_cb(vi->rvq); - __napi_schedule(&vi->napi); + if (napi_schedule_prep(&rq->napi)) { + virtqueue_disable_cb(rq->rvq); + __napi_schedule(&rq->napi); } } +static void virtnet_napi_enable_all_queues(struct virtnet_info *vi) +{ + int i; + + for (i = 0; i < vi->numtxqs; i++) + virtnet_napi_enable(vi->rq[i]); +} + static void refill_work(struct work_struct *work) { - struct virtnet_info *vi; + struct napi_struct *napi; + struct receive_queue *rq; 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); + rq = container_of(work, struct receive_queue, refill.work); + napi = &rq->napi; + + napi_disable(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); + schedule_delayed_work(&rq->refill, HZ/2); } static int virtnet_poll(struct napi_struct *napi, int budget) { - struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi); + struct receive_queue *rq = container_of(napi, struct receive_queue, + 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; + (buf = virtqueue_get_buf(rq->rvq, &len)) != NULL) { + receive_buf(rq, buf, len); + --rq->num; received++; } - if (vi->num < vi->max / 2) { - if (!try_fill_recv(vi, GFP_ATOMIC)) - schedule_delayed_work(&vi->refill, 0); + if (rq->num < rq->max / 2) { + if (!try_fill_recv(rq, GFP_ATOMIC)) + schedule_delayed_work(&rq->refill, 0); } /* Out of packets? */ if (received < budget) { napi_complete(napi); - if (unlikely(!virtqueue_enable_cb(vi->rvq)) && + if (unlikely(!virtqueue_enable_cb(rq->rvq)) && napi_schedule_prep(napi)) { - virtqueue_disable_cb(vi->rvq); + virtqueue_disable_cb(rq->rvq); __napi_schedule(napi); goto again; } @@ -527,13 +569,14 @@ again: return received; } -static unsigned int free_old_xmit_skbs(struct virtnet_info *vi) +static unsigned int free_old_xmit_skbs(struct virtnet_info *vi, + struct virtqueue *svq) { 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) { + while ((skb = virtqueue_get_buf(svq, &len)) != NULL) { pr_debug("Sent skb %p\n", skb); u64_stats_update_begin(&stats->syncp); @@ -547,7 +590,8 @@ static unsigned int free_old_xmit_skbs(struct virtnet_info *vi) return tot_sgs; } -static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb) +static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb, + struct virtqueue *svq, struct scatterlist *tx_sg) { struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb); const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest; @@ -585,12 +629,12 @@ static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb) /* Encode metadata header at front. */ if (vi->mergeable_rx_bufs) - sg_set_buf(vi->tx_sg, &hdr->mhdr, sizeof hdr->mhdr); + sg_set_buf(tx_sg, &hdr->mhdr, sizeof hdr->mhdr); else - sg_set_buf(vi->tx_sg, &hdr->hdr, sizeof hdr->hdr); + sg_set_buf(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, + hdr->num_sg = skb_to_sgvec(skb, tx_sg + 1, 0, skb->len) + 1; + return virtqueue_add_buf(svq, tx_sg, hdr->num_sg, 0, skb); } @@ -598,31 +642,34 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); int capacity; + int qnum = skb_get_queue_mapping(skb); + struct virtqueue *svq = vi->sq[qnum]->svq; /* Free up any pending old buffers before queueing new ones. */ - free_old_xmit_skbs(vi); + free_old_xmit_skbs(vi, svq); /* Try to transmit */ - capacity = xmit_skb(vi, skb); + capacity = xmit_skb(vi, skb, svq, vi->sq[qnum]->tx_sg); /* 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"); + "TXQ (%d) failure: out of memory\n", + qnum); } else { dev->stats.tx_fifo_errors++; dev_warn(&dev->dev, - "Unexpected TX queue failure: %d\n", - capacity); + "Unexpected TXQ (%d) failure: %d\n", + qnum, capacity); } } dev->stats.tx_dropped++; kfree_skb(skb); return NETDEV_TX_OK; } - virtqueue_kick(vi->svq); + virtqueue_kick(svq); /* Don't wait up for transmitted skbs to be freed. */ skb_orphan(skb); @@ -631,13 +678,13 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) /* 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))) { + netif_stop_subqueue(dev, qnum); + if (unlikely(!virtqueue_enable_cb_delayed(svq))) { /* More just got used, free them then recheck. */ - capacity += free_old_xmit_skbs(vi); + capacity += free_old_xmit_skbs(vi, svq); if (capacity >= 2+MAX_SKB_FRAGS) { - netif_start_queue(dev); - virtqueue_disable_cb(vi->svq); + netif_start_subqueue(dev, qnum); + virtqueue_disable_cb(svq); } } } @@ -700,8 +747,10 @@ static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev, static void virtnet_netpoll(struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); + int i; - napi_schedule(&vi->napi); + for (i = 0; i < vi->numtxqs; i++) + napi_schedule(&vi->rq[i]->napi); } #endif @@ -709,7 +758,7 @@ static int virtnet_open(struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); - virtnet_napi_enable(vi); + virtnet_napi_enable_all_queues(vi); return 0; } @@ -761,8 +810,10 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, static int virtnet_close(struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); + int i; - napi_disable(&vi->napi); + for (i = 0; i < vi->numtxqs; i++) + napi_disable(&vi->rq[i]->napi); return 0; } @@ -919,10 +970,10 @@ static void virtnet_update_status(struct virtnet_info *vi) if (vi->status & VIRTIO_NET_S_LINK_UP) { netif_carrier_on(vi->dev); - netif_wake_queue(vi->dev); + netif_tx_wake_all_queues(vi->dev); } else { netif_carrier_off(vi->dev); - netif_stop_queue(vi->dev); + netif_tx_stop_all_queues(vi->dev); } } @@ -933,18 +984,222 @@ static void virtnet_config_changed(struct virtio_device *vdev) virtnet_update_status(vi); } +static void free_receive_bufs(struct virtnet_info *vi) +{ + int i; + + for (i = 0; i < vi->numtxqs; i++) { + BUG_ON(vi->rq[i] == NULL); + while (vi->rq[i]->pages) + __free_pages(get_a_page(vi->rq[i], GFP_KERNEL), 0); + } +} + +/* Free memory allocated for send and receive queues */ +static void free_rq_sq(struct virtnet_info *vi) +{ + int i; + + if (vi->rq) { + for (i = 0; i < vi->numtxqs; i++) + kfree(vi->rq[i]); + kfree(vi->rq); + } + + if (vi->sq) { + for (i = 0; i < vi->numtxqs; i++) + kfree(vi->sq[i]); + kfree(vi->sq); + } +} + +static void free_unused_bufs(struct virtnet_info *vi) +{ + void *buf; + int i; + + for (i = 0; i < vi->numtxqs; i++) { + struct virtqueue *svq = vi->sq[i]->svq; + + while (1) { + buf = virtqueue_detach_unused_buf(svq); + if (!buf) + break; + dev_kfree_skb(buf); + } + } + + for (i = 0; i < vi->numtxqs; i++) { + struct virtqueue *rvq = vi->rq[i]->rvq; + + while (1) { + buf = virtqueue_detach_unused_buf(rvq); + if (!buf) + break; + if (vi->mergeable_rx_bufs || 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); + } +} + +#define MAX_DEVICE_NAME 16 +static int initialize_vqs(struct virtnet_info *vi, int numtxqs) +{ + vq_callback_t **callbacks; + struct virtqueue **vqs; + int i, err = -ENOMEM; + int totalvqs; + char **names; + + /* Allocate receive queues */ + vi->rq = kcalloc(numtxqs, sizeof(*vi->rq), GFP_KERNEL); + if (!vi->rq) + goto out; + for (i = 0; i < numtxqs; i++) { + vi->rq[i] = kzalloc(sizeof(*vi->rq[i]), GFP_KERNEL); + if (!vi->rq[i]) + goto out; + } + + /* Allocate send queues */ + vi->sq = kcalloc(numtxqs, sizeof(*vi->sq), GFP_KERNEL); + if (!vi->sq) + goto out; + for (i = 0; i < numtxqs; i++) { + vi->sq[i] = kzalloc(sizeof(*vi->sq[i]), GFP_KERNEL); + if (!vi->sq[i]) + goto out; + } + + /* setup initial receive and send queue parameters */ + for (i = 0; i < numtxqs; i++) { + vi->rq[i]->vi = vi; + vi->rq[i]->pages = NULL; + INIT_DELAYED_WORK(&vi->rq[i]->refill, refill_work); + netif_napi_add(vi->dev, &vi->rq[i]->napi, virtnet_poll, + napi_weight); + + sg_init_table(vi->rq[i]->rx_sg, ARRAY_SIZE(vi->rq[i]->rx_sg)); + sg_init_table(vi->sq[i]->tx_sg, ARRAY_SIZE(vi->sq[i]->tx_sg)); + } + + /* + * We expect 1 RX virtqueue followed by 1 TX virtqueues, followed + * by the same 'numtxqs-1' times, and optionally one control virtqueue. + */ + totalvqs = numtxqs * 2 + + virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ); + + /* Allocate space for find_vqs parameters */ + vqs = kmalloc(totalvqs * sizeof(*vqs), GFP_KERNEL); + callbacks = kmalloc(totalvqs * sizeof(*callbacks), GFP_KERNEL); + names = kzalloc(totalvqs * sizeof(*names), GFP_KERNEL); + if (!vqs || !callbacks || !names) + goto free_params; + +#if 1 + /* Allocate/initialize parameters for recv/send virtqueues */ + for (i = 0; i < numtxqs * 2; i++) { + names[i] = kmalloc(MAX_DEVICE_NAME * sizeof(*names[i]), + GFP_KERNEL); + if (!names[i]) + goto free_params; + + if (!(i & 1)) { /* RX */ + callbacks[i] = skb_recv_done; + sprintf(names[i], "input.%d", i / 2); + } else { + callbacks[i] = skb_xmit_done; + sprintf(names[i], "output.%d", i / 2); + } + } + + /* Parameters for control virtqueue, if any */ + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) { + callbacks[i] = NULL; + names[i] = "control"; + } +#else + /* Allocate/initialize parameters for recv virtqueues */ + for (i = 0; i < numtxqs * 2; i += 2) { + callbacks[i] = skb_recv_done; + names[i] = kmalloc(MAX_DEVICE_NAME * sizeof(*names[i]), + GFP_KERNEL); + if (!names[i]) + goto free_params; + sprintf(names[i], "input.%d", i / 2); + } + + /* Allocate/initialize parameters for send virtqueues */ + for (i = 1; i < numtxqs * 2; i += 2) { + callbacks[i] = skb_xmit_done; + names[i] = kmalloc(MAX_DEVICE_NAME * sizeof(*names[i]), + GFP_KERNEL); + if (!names[i]) + goto free_params; + sprintf(names[i], "output.%d", i / 2); + } + + /* Parameters for control virtqueue, if any */ + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) { + callbacks[i - 1] = NULL; + names[i - 1] = "control"; + } +#endif + + err = vi->vdev->config->find_vqs(vi->vdev, totalvqs, vqs, callbacks, + (const char **)names); + if (err) + goto free_params; + + /* Assign the allocated vqs alternatively for RX/TX */ + for (i = 0; i < numtxqs * 2; i += 2) { + vi->rq[i/2]->rvq = vqs[i]; + vi->sq[i/2]->svq = vqs[i + 1]; + } + + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) + vi->cvq = vqs[i]; + +free_params: + if (names) { + for (i = 0; i < numtxqs * 2; i++) + kfree(names[i]); + kfree(names); + } + + kfree(callbacks); + kfree(vqs); + +out: + if (err) + free_rq_sq(vi); + + return err; +} + static int virtnet_probe(struct virtio_device *vdev) { - int err; + int i, err; + u16 numtxqs; + u16 num_queue_pairs = 2; 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; + + /* Find if host supports MULTIQUEUE */ + err = virtio_config_val(vdev, VIRTIO_NET_F_MULTIQUEUE, + offsetof(struct virtio_net_config, + num_queue_pairs), &num_queue_pairs); + numtxqs = num_queue_pairs / 2; + if (!numtxqs) + numtxqs = 1; /* Allocate ourselves a network device with room for our info */ - dev = alloc_etherdev(sizeof(struct virtnet_info)); + dev = alloc_etherdev_mq(sizeof(struct virtnet_info), numtxqs); if (!dev) return -ENOMEM; @@ -991,19 +1246,14 @@ static int virtnet_probe(struct virtio_device *vdev) /* 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)); + vi->numtxqs = numtxqs; /* If we can receive ANY GSO packets, we must allocate large ones. */ if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) || @@ -1014,23 +1264,14 @@ static int virtnet_probe(struct virtio_device *vdev) 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); + /* Initialize our rx/tx queue parameters, and invoke find_vqs */ + err = initialize_vqs(vi, numtxqs); 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; - } + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) && + virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN)) + dev->features |= NETIF_F_HW_VLAN_FILTER; err = register_netdev(dev); if (err) { @@ -1039,14 +1280,21 @@ static int virtnet_probe(struct virtio_device *vdev) } /* 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; + for (i = 0; i < numtxqs; 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) { + if (i) + free_unused_bufs(vi); + err = -ENOMEM; + goto free_recv_bufs; + } } + dev_info(&dev->dev, "(virtio-net) Allocated %d RX & TX vq's\n", + numtxqs); + /* 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)) { @@ -1057,61 +1305,51 @@ static int virtnet_probe(struct virtio_device *vdev) netif_carrier_on(dev); } - pr_debug("virtnet: registered device %s\n", dev->name); + pr_debug("virtnet: registered device %s with %d RX and TX vq's\n", + dev->name, numtxqs); return 0; -unregister: +free_recv_bufs: + free_receive_bufs(vi); unregister_netdev(dev); - cancel_delayed_work_sync(&vi->refill); + free_vqs: + for (i = 0; i < numtxqs; i++) + cancel_delayed_work_sync(&vi->rq[i]->refill); vdev->config->del_vqs(vdev); + free_rq_sq(vi); + 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; + int i; /* Stop all the virtqueues. */ vdev->config->reset(vdev); unregister_netdev(vi->dev); - cancel_delayed_work_sync(&vi->refill); + + for (i = 0; i < vi->numtxqs; i++) + cancel_delayed_work_sync(&vi->rq[i]->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_receive_bufs(vi); + + /* Free memory for send and receive queues */ + free_rq_sq(vi); free_percpu(vi->stats); free_netdev(vi->dev); @@ -1129,7 +1367,7 @@ static unsigned int features[] = { 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_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, VIRTIO_NET_F_MULTIQUEUE, }; static struct virtio_driver virtio_net_driver = { diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index 970d5a2..fa85ac3 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -49,6 +49,7 @@ #define VIRTIO_NET_F_CTRL_RX 18 /* Control channel RX mode support */ #define VIRTIO_NET_F_CTRL_VLAN 19 /* Control channel VLAN filtering */ #define VIRTIO_NET_F_CTRL_RX_EXTRA 20 /* Extra RX mode control support */ +#define VIRTIO_NET_F_MULTIQUEUE 21 /* Device supports multiple TXQ/RXQ */ #define VIRTIO_NET_S_LINK_UP 1 /* Link is up */ @@ -57,6 +58,8 @@ struct virtio_net_config { __u8 mac[6]; /* See VIRTIO_NET_F_STATUS and VIRTIO_NET_S_* above */ __u16 status; + /* total number of RX/TX queues */ + __u16 num_queue_pairs; } __attribute__((packed)); /* This is the first element of the scatter-gather list. 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