1 /* A network driver using virtio.
3 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
19 #include <linux/netdevice.h>
20 #include <linux/etherdevice.h>
21 #include <linux/ethtool.h>
22 #include <linux/module.h>
23 #include <linux/virtio.h>
24 #include <linux/virtio_net.h>
25 #include <linux/bpf.h>
26 #include <linux/bpf_trace.h>
27 #include <linux/scatterlist.h>
28 #include <linux/if_vlan.h>
29 #include <linux/slab.h>
30 #include <linux/cpu.h>
31 #include <linux/average.h>
32 #include <linux/filter.h>
33 #include <net/route.h>
35 static int napi_weight = NAPI_POLL_WEIGHT;
36 module_param(napi_weight, int, 0444);
38 static bool csum = true, gso = true, napi_tx;
39 module_param(csum, bool, 0444);
40 module_param(gso, bool, 0444);
41 module_param(napi_tx, bool, 0644);
43 /* FIXME: MTU in config. */
44 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
45 #define GOOD_COPY_LEN 128
47 #define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
49 /* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
50 #define VIRTIO_XDP_HEADROOM 256
52 /* RX packet size EWMA. The average packet size is used to determine the packet
53 * buffer size when refilling RX rings. As the entire RX ring may be refilled
54 * at once, the weight is chosen so that the EWMA will be insensitive to short-
55 * term, transient changes in packet size.
57 DECLARE_EWMA(pkt_len, 0, 64)
59 #define VIRTNET_DRIVER_VERSION "1.0.0"
61 static const unsigned long guest_offloads[] = {
62 VIRTIO_NET_F_GUEST_TSO4,
63 VIRTIO_NET_F_GUEST_TSO6,
64 VIRTIO_NET_F_GUEST_ECN,
65 VIRTIO_NET_F_GUEST_UFO
68 struct virtnet_stats {
69 struct u64_stats_sync tx_syncp;
70 struct u64_stats_sync rx_syncp;
78 /* Internal representation of a send virtqueue */
80 /* Virtqueue associated with this send _queue */
83 /* TX: fragments + linear part + virtio header */
84 struct scatterlist sg[MAX_SKB_FRAGS + 2];
86 /* Name of the send queue: output.$index */
89 struct napi_struct napi;
92 /* Internal representation of a receive virtqueue */
93 struct receive_queue {
94 /* Virtqueue associated with this receive_queue */
97 struct napi_struct napi;
99 struct bpf_prog __rcu *xdp_prog;
101 /* Chain pages by the private ptr. */
104 /* Average packet length for mergeable receive buffers. */
105 struct ewma_pkt_len mrg_avg_pkt_len;
107 /* Page frag for packet buffer allocation. */
108 struct page_frag alloc_frag;
110 /* RX: fragments + linear part + virtio header */
111 struct scatterlist sg[MAX_SKB_FRAGS + 2];
113 /* Min single buffer size for mergeable buffers case. */
114 unsigned int min_buf_len;
116 /* Name of this receive queue: input.$index */
120 struct virtnet_info {
121 struct virtio_device *vdev;
122 struct virtqueue *cvq;
123 struct net_device *dev;
124 struct send_queue *sq;
125 struct receive_queue *rq;
128 /* Max # of queue pairs supported by the device */
131 /* # of queue pairs currently used by the driver */
132 u16 curr_queue_pairs;
134 /* # of XDP queue pairs currently used by the driver */
137 /* I like... big packets and I cannot lie! */
140 /* Host will merge rx buffers for big packets (shake it! shake it!) */
141 bool mergeable_rx_bufs;
143 /* Has control virtqueue */
146 /* Host can handle any s/g split between our header and packet data */
149 /* Packet virtio header size */
152 /* Active statistics */
153 struct virtnet_stats __percpu *stats;
155 /* Work struct for refilling if we run low on memory. */
156 struct delayed_work refill;
158 /* Work struct for config space updates */
159 struct work_struct config_work;
161 /* Does the affinity hint is set for virtqueues? */
162 bool affinity_hint_set;
164 /* CPU hotplug instances for online & dead */
165 struct hlist_node node;
166 struct hlist_node node_dead;
168 /* Control VQ buffers: protected by the rtnl lock */
169 struct virtio_net_ctrl_hdr ctrl_hdr;
170 virtio_net_ctrl_ack ctrl_status;
171 struct virtio_net_ctrl_mq ctrl_mq;
177 /* Ethtool settings */
181 unsigned long guest_offloads;
184 struct padded_vnet_hdr {
185 struct virtio_net_hdr_mrg_rxbuf hdr;
187 * hdr is in a separate sg buffer, and data sg buffer shares same page
188 * with this header sg. This padding makes next sg 16 byte aligned
194 /* Converting between virtqueue no. and kernel tx/rx queue no.
195 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
197 static int vq2txq(struct virtqueue *vq)
199 return (vq->index - 1) / 2;
202 static int txq2vq(int txq)
207 static int vq2rxq(struct virtqueue *vq)
209 return vq->index / 2;
212 static int rxq2vq(int rxq)
217 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
219 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
223 * private is used to chain pages for big packets, put the whole
224 * most recent used list in the beginning for reuse
226 static void give_pages(struct receive_queue *rq, struct page *page)
230 /* Find end of list, sew whole thing into vi->rq.pages. */
231 for (end = page; end->private; end = (struct page *)end->private);
232 end->private = (unsigned long)rq->pages;
236 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
238 struct page *p = rq->pages;
241 rq->pages = (struct page *)p->private;
242 /* clear private here, it is used to chain pages */
245 p = alloc_page(gfp_mask);
249 static void virtqueue_napi_schedule(struct napi_struct *napi,
250 struct virtqueue *vq)
252 if (napi_schedule_prep(napi)) {
253 virtqueue_disable_cb(vq);
254 __napi_schedule(napi);
258 static void virtqueue_napi_complete(struct napi_struct *napi,
259 struct virtqueue *vq, int processed)
263 opaque = virtqueue_enable_cb_prepare(vq);
264 if (napi_complete_done(napi, processed) &&
265 unlikely(virtqueue_poll(vq, opaque)))
266 virtqueue_napi_schedule(napi, vq);
269 static void skb_xmit_done(struct virtqueue *vq)
271 struct virtnet_info *vi = vq->vdev->priv;
272 struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
274 /* Suppress further interrupts. */
275 virtqueue_disable_cb(vq);
278 virtqueue_napi_schedule(napi, vq);
280 /* We were probably waiting for more output buffers. */
281 netif_wake_subqueue(vi->dev, vq2txq(vq));
284 #define MRG_CTX_HEADER_SHIFT 22
285 static void *mergeable_len_to_ctx(unsigned int truesize,
286 unsigned int headroom)
288 return (void *)(unsigned long)((headroom << MRG_CTX_HEADER_SHIFT) | truesize);
291 static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx)
293 return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT;
296 static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx)
298 return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1);
301 /* Called from bottom half context */
302 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
303 struct receive_queue *rq,
304 struct page *page, unsigned int offset,
305 unsigned int len, unsigned int truesize)
308 struct virtio_net_hdr_mrg_rxbuf *hdr;
309 unsigned int copy, hdr_len, hdr_padded_len;
312 p = page_address(page) + offset;
314 /* copy small packet so we can reuse these pages for small data */
315 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
319 hdr = skb_vnet_hdr(skb);
321 hdr_len = vi->hdr_len;
322 if (vi->mergeable_rx_bufs)
323 hdr_padded_len = sizeof(*hdr);
325 hdr_padded_len = sizeof(struct padded_vnet_hdr);
327 memcpy(hdr, p, hdr_len);
330 offset += hdr_padded_len;
334 if (copy > skb_tailroom(skb))
335 copy = skb_tailroom(skb);
336 skb_put_data(skb, p, copy);
341 if (vi->mergeable_rx_bufs) {
343 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
350 * Verify that we can indeed put this data into a skb.
351 * This is here to handle cases when the device erroneously
352 * tries to receive more than is possible. This is usually
353 * the case of a broken device.
355 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
356 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
360 BUG_ON(offset >= PAGE_SIZE);
362 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
363 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
364 frag_size, truesize);
366 page = (struct page *)page->private;
371 give_pages(rq, page);
376 static void virtnet_xdp_flush(struct net_device *dev)
378 struct virtnet_info *vi = netdev_priv(dev);
379 struct send_queue *sq;
382 qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
385 virtqueue_kick(sq->vq);
388 static bool __virtnet_xdp_xmit(struct virtnet_info *vi,
389 struct xdp_buff *xdp)
391 struct virtio_net_hdr_mrg_rxbuf *hdr;
393 struct send_queue *sq;
398 qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
401 /* Free up any pending old buffers before queueing new ones. */
402 while ((xdp_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) {
403 struct page *sent_page = virt_to_head_page(xdp_sent);
408 xdp->data -= vi->hdr_len;
409 /* Zero header and leave csum up to XDP layers */
411 memset(hdr, 0, vi->hdr_len);
413 sg_init_one(sq->sg, xdp->data, xdp->data_end - xdp->data);
415 err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp->data, GFP_ATOMIC);
417 struct page *page = virt_to_head_page(xdp->data);
426 static int virtnet_xdp_xmit(struct net_device *dev, struct xdp_buff *xdp)
428 struct virtnet_info *vi = netdev_priv(dev);
429 bool sent = __virtnet_xdp_xmit(vi, xdp);
436 static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
438 return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0;
441 /* We copy the packet for XDP in the following cases:
443 * 1) Packet is scattered across multiple rx buffers.
444 * 2) Headroom space is insufficient.
446 * This is inefficient but it's a temporary condition that
447 * we hit right after XDP is enabled and until queue is refilled
448 * with large buffers with sufficient headroom - so it should affect
449 * at most queue size packets.
450 * Afterwards, the conditions to enable
451 * XDP should preclude the underlying device from sending packets
452 * across multiple buffers (num_buf > 1), and we make sure buffers
453 * have enough headroom.
455 static struct page *xdp_linearize_page(struct receive_queue *rq,
462 struct page *page = alloc_page(GFP_ATOMIC);
467 memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
475 buf = virtqueue_get_buf(rq->vq, &buflen);
479 p = virt_to_head_page(buf);
480 off = buf - page_address(p);
482 /* guard against a misconfigured or uncooperative backend that
483 * is sending packet larger than the MTU.
485 if ((page_off + buflen) > PAGE_SIZE) {
490 memcpy(page_address(page) + page_off,
491 page_address(p) + off, buflen);
496 /* Headroom does not contribute to packet length */
497 *len = page_off - VIRTIO_XDP_HEADROOM;
500 __free_pages(page, 0);
504 static struct sk_buff *receive_small(struct net_device *dev,
505 struct virtnet_info *vi,
506 struct receive_queue *rq,
507 void *buf, void *ctx,
512 struct bpf_prog *xdp_prog;
513 unsigned int xdp_headroom = (unsigned long)ctx;
514 unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
515 unsigned int headroom = vi->hdr_len + header_offset;
516 unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
517 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
518 struct page *page = virt_to_head_page(buf);
519 unsigned int delta = 0, err;
520 struct page *xdp_page;
524 xdp_prog = rcu_dereference(rq->xdp_prog);
526 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
531 if (unlikely(hdr->hdr.gso_type || hdr->hdr.flags))
534 if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
535 int offset = buf - page_address(page) + header_offset;
536 unsigned int tlen = len + vi->hdr_len;
539 xdp_headroom = virtnet_get_headroom(vi);
540 header_offset = VIRTNET_RX_PAD + xdp_headroom;
541 headroom = vi->hdr_len + header_offset;
542 buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
543 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
544 xdp_page = xdp_linearize_page(rq, &num_buf, page,
545 offset, header_offset,
550 buf = page_address(xdp_page);
555 xdp.data_hard_start = buf + VIRTNET_RX_PAD + vi->hdr_len;
556 xdp.data = xdp.data_hard_start + xdp_headroom;
557 xdp_set_data_meta_invalid(&xdp);
558 xdp.data_end = xdp.data + len;
559 orig_data = xdp.data;
560 act = bpf_prog_run_xdp(xdp_prog, &xdp);
564 /* Recalculate length in case bpf program changed it */
565 delta = orig_data - xdp.data;
568 if (unlikely(!__virtnet_xdp_xmit(vi, &xdp)))
569 trace_xdp_exception(vi->dev, xdp_prog, act);
575 err = xdp_do_redirect(dev, &xdp, xdp_prog);
581 bpf_warn_invalid_xdp_action(act);
583 trace_xdp_exception(vi->dev, xdp_prog, act);
590 skb = build_skb(buf, buflen);
595 skb_reserve(skb, headroom - delta);
596 skb_put(skb, len + delta);
598 buf += header_offset;
599 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
600 } /* keep zeroed vnet hdr since packet was changed by bpf */
607 dev->stats.rx_dropped++;
613 static struct sk_buff *receive_big(struct net_device *dev,
614 struct virtnet_info *vi,
615 struct receive_queue *rq,
619 struct page *page = buf;
620 struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);
628 dev->stats.rx_dropped++;
629 give_pages(rq, page);
633 static struct sk_buff *receive_mergeable(struct net_device *dev,
634 struct virtnet_info *vi,
635 struct receive_queue *rq,
641 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
642 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
643 struct page *page = virt_to_head_page(buf);
644 int offset = buf - page_address(page);
645 struct sk_buff *head_skb, *curr_skb;
646 struct bpf_prog *xdp_prog;
647 unsigned int truesize;
648 unsigned int headroom = mergeable_ctx_to_headroom(ctx);
654 xdp_prog = rcu_dereference(rq->xdp_prog);
656 struct page *xdp_page;
661 /* This happens when rx buffer size is underestimated */
662 if (unlikely(num_buf > 1 ||
663 headroom < virtnet_get_headroom(vi))) {
664 /* linearize data for XDP */
665 xdp_page = xdp_linearize_page(rq, &num_buf,
671 offset = VIRTIO_XDP_HEADROOM;
676 /* Transient failure which in theory could occur if
677 * in-flight packets from before XDP was enabled reach
678 * the receive path after XDP is loaded. In practice I
679 * was not able to create this condition.
681 if (unlikely(hdr->hdr.gso_type))
684 /* Allow consuming headroom but reserve enough space to push
685 * the descriptor on if we get an XDP_TX return code.
687 data = page_address(xdp_page) + offset;
688 xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len;
689 xdp.data = data + vi->hdr_len;
690 xdp_set_data_meta_invalid(&xdp);
691 xdp.data_end = xdp.data + (len - vi->hdr_len);
692 act = bpf_prog_run_xdp(xdp_prog, &xdp);
695 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
699 /* recalculate offset to account for any header
700 * adjustments. Note other cases do not build an
701 * skb and avoid using offset
704 page_address(xdp_page) - vi->hdr_len;
706 /* We can only create skb based on xdp_page. */
707 if (unlikely(xdp_page != page)) {
710 head_skb = page_to_skb(vi, rq, xdp_page,
711 offset, len, PAGE_SIZE);
716 if (unlikely(!__virtnet_xdp_xmit(vi, &xdp)))
717 trace_xdp_exception(vi->dev, xdp_prog, act);
720 if (unlikely(xdp_page != page))
725 err = xdp_do_redirect(dev, &xdp, xdp_prog);
731 bpf_warn_invalid_xdp_action(act);
733 trace_xdp_exception(vi->dev, xdp_prog, act);
735 if (unlikely(xdp_page != page))
736 __free_pages(xdp_page, 0);
742 truesize = mergeable_ctx_to_truesize(ctx);
743 if (unlikely(len > truesize)) {
744 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
745 dev->name, len, (unsigned long)ctx);
746 dev->stats.rx_length_errors++;
750 head_skb = page_to_skb(vi, rq, page, offset, len, truesize);
753 if (unlikely(!curr_skb))
758 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
759 if (unlikely(!ctx)) {
760 pr_debug("%s: rx error: %d buffers out of %d missing\n",
762 virtio16_to_cpu(vi->vdev,
764 dev->stats.rx_length_errors++;
768 page = virt_to_head_page(buf);
770 truesize = mergeable_ctx_to_truesize(ctx);
771 if (unlikely(len > truesize)) {
772 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
773 dev->name, len, (unsigned long)ctx);
774 dev->stats.rx_length_errors++;
778 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
779 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
780 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
784 if (curr_skb == head_skb)
785 skb_shinfo(curr_skb)->frag_list = nskb;
787 curr_skb->next = nskb;
789 head_skb->truesize += nskb->truesize;
792 if (curr_skb != head_skb) {
793 head_skb->data_len += len;
794 head_skb->len += len;
795 head_skb->truesize += truesize;
797 offset = buf - page_address(page);
798 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
800 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
803 skb_add_rx_frag(curr_skb, num_skb_frags, page,
804 offset, len, truesize);
808 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
816 buf = virtqueue_get_buf(rq->vq, &len);
817 if (unlikely(!buf)) {
818 pr_debug("%s: rx error: %d buffers missing\n",
820 dev->stats.rx_length_errors++;
823 page = virt_to_head_page(buf);
827 dev->stats.rx_dropped++;
828 dev_kfree_skb(head_skb);
833 static int receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
834 void *buf, unsigned int len, void **ctx, bool *xdp_xmit)
836 struct net_device *dev = vi->dev;
838 struct virtio_net_hdr_mrg_rxbuf *hdr;
841 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
842 pr_debug("%s: short packet %i\n", dev->name, len);
843 dev->stats.rx_length_errors++;
844 if (vi->mergeable_rx_bufs) {
845 put_page(virt_to_head_page(buf));
846 } else if (vi->big_packets) {
849 put_page(virt_to_head_page(buf));
854 if (vi->mergeable_rx_bufs)
855 skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit);
856 else if (vi->big_packets)
857 skb = receive_big(dev, vi, rq, buf, len);
859 skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit);
864 hdr = skb_vnet_hdr(skb);
868 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
869 skb->ip_summed = CHECKSUM_UNNECESSARY;
871 if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
872 virtio_is_little_endian(vi->vdev))) {
873 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
874 dev->name, hdr->hdr.gso_type,
879 skb->protocol = eth_type_trans(skb, dev);
880 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
881 ntohs(skb->protocol), skb->len, skb->pkt_type);
883 napi_gro_receive(&rq->napi, skb);
887 dev->stats.rx_frame_errors++;
892 /* Unlike mergeable buffers, all buffers are allocated to the
893 * same size, except for the headroom. For this reason we do
894 * not need to use mergeable_len_to_ctx here - it is enough
895 * to store the headroom as the context ignoring the truesize.
897 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
900 struct page_frag *alloc_frag = &rq->alloc_frag;
902 unsigned int xdp_headroom = virtnet_get_headroom(vi);
903 void *ctx = (void *)(unsigned long)xdp_headroom;
904 int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
907 len = SKB_DATA_ALIGN(len) +
908 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
909 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
912 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
913 get_page(alloc_frag->page);
914 alloc_frag->offset += len;
915 sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
916 vi->hdr_len + GOOD_PACKET_LEN);
917 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
919 put_page(virt_to_head_page(buf));
923 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
926 struct page *first, *list = NULL;
930 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
932 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
933 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
934 first = get_a_page(rq, gfp);
937 give_pages(rq, list);
940 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
942 /* chain new page in list head to match sg */
943 first->private = (unsigned long)list;
947 first = get_a_page(rq, gfp);
949 give_pages(rq, list);
952 p = page_address(first);
954 /* rq->sg[0], rq->sg[1] share the same page */
955 /* a separated rq->sg[0] for header - required in case !any_header_sg */
956 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
958 /* rq->sg[1] for data packet, from offset */
959 offset = sizeof(struct padded_vnet_hdr);
960 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
962 /* chain first in list head */
963 first->private = (unsigned long)list;
964 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
967 give_pages(rq, first);
972 static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
973 struct ewma_pkt_len *avg_pkt_len)
975 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
978 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
979 rq->min_buf_len, PAGE_SIZE - hdr_len);
980 return ALIGN(len, L1_CACHE_BYTES);
983 static int add_recvbuf_mergeable(struct virtnet_info *vi,
984 struct receive_queue *rq, gfp_t gfp)
986 struct page_frag *alloc_frag = &rq->alloc_frag;
987 unsigned int headroom = virtnet_get_headroom(vi);
991 unsigned int len, hole;
993 len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len);
994 if (unlikely(!skb_page_frag_refill(len + headroom, alloc_frag, gfp)))
997 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
998 buf += headroom; /* advance address leaving hole at front of pkt */
999 get_page(alloc_frag->page);
1000 alloc_frag->offset += len + headroom;
1001 hole = alloc_frag->size - alloc_frag->offset;
1002 if (hole < len + headroom) {
1003 /* To avoid internal fragmentation, if there is very likely not
1004 * enough space for another buffer, add the remaining space to
1005 * the current buffer.
1008 alloc_frag->offset += hole;
1011 sg_init_one(rq->sg, buf, len);
1012 ctx = mergeable_len_to_ctx(len, headroom);
1013 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1015 put_page(virt_to_head_page(buf));
1021 * Returns false if we couldn't fill entirely (OOM).
1023 * Normally run in the receive path, but can also be run from ndo_open
1024 * before we're receiving packets, or from refill_work which is
1025 * careful to disable receiving (using napi_disable).
1027 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
1035 if (vi->mergeable_rx_bufs)
1036 err = add_recvbuf_mergeable(vi, rq, gfp);
1037 else if (vi->big_packets)
1038 err = add_recvbuf_big(vi, rq, gfp);
1040 err = add_recvbuf_small(vi, rq, gfp);
1042 oom = err == -ENOMEM;
1045 } while (rq->vq->num_free);
1046 virtqueue_kick(rq->vq);
1050 static void skb_recv_done(struct virtqueue *rvq)
1052 struct virtnet_info *vi = rvq->vdev->priv;
1053 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
1055 virtqueue_napi_schedule(&rq->napi, rvq);
1058 static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
1062 /* If all buffers were filled by other side before we napi_enabled, we
1063 * won't get another interrupt, so process any outstanding packets now.
1064 * Call local_bh_enable after to trigger softIRQ processing.
1067 virtqueue_napi_schedule(napi, vq);
1071 static void virtnet_napi_tx_enable(struct virtnet_info *vi,
1072 struct virtqueue *vq,
1073 struct napi_struct *napi)
1078 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
1079 * enable the feature if this is likely affine with the transmit path.
1081 if (!vi->affinity_hint_set) {
1086 return virtnet_napi_enable(vq, napi);
1089 static void virtnet_napi_tx_disable(struct napi_struct *napi)
1095 static void refill_work(struct work_struct *work)
1097 struct virtnet_info *vi =
1098 container_of(work, struct virtnet_info, refill.work);
1102 for (i = 0; i < vi->curr_queue_pairs; i++) {
1103 struct receive_queue *rq = &vi->rq[i];
1105 napi_disable(&rq->napi);
1106 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
1107 virtnet_napi_enable(rq->vq, &rq->napi);
1109 /* In theory, this can happen: if we don't get any buffers in
1110 * we will *never* try to fill again.
1113 schedule_delayed_work(&vi->refill, HZ/2);
1117 static int virtnet_receive(struct receive_queue *rq, int budget, bool *xdp_xmit)
1119 struct virtnet_info *vi = rq->vq->vdev->priv;
1120 unsigned int len, received = 0, bytes = 0;
1122 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
1124 if (!vi->big_packets || vi->mergeable_rx_bufs) {
1127 while (received < budget &&
1128 (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) {
1129 bytes += receive_buf(vi, rq, buf, len, ctx, xdp_xmit);
1133 while (received < budget &&
1134 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
1135 bytes += receive_buf(vi, rq, buf, len, NULL, xdp_xmit);
1140 if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
1141 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
1142 schedule_delayed_work(&vi->refill, 0);
1145 u64_stats_update_begin(&stats->rx_syncp);
1146 stats->rx_bytes += bytes;
1147 stats->rx_packets += received;
1148 u64_stats_update_end(&stats->rx_syncp);
1153 static void free_old_xmit_skbs(struct send_queue *sq)
1155 struct sk_buff *skb;
1157 struct virtnet_info *vi = sq->vq->vdev->priv;
1158 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
1159 unsigned int packets = 0;
1160 unsigned int bytes = 0;
1162 while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1163 pr_debug("Sent skb %p\n", skb);
1168 dev_consume_skb_any(skb);
1171 /* Avoid overhead when no packets have been processed
1172 * happens when called speculatively from start_xmit.
1177 u64_stats_update_begin(&stats->tx_syncp);
1178 stats->tx_bytes += bytes;
1179 stats->tx_packets += packets;
1180 u64_stats_update_end(&stats->tx_syncp);
1183 static void virtnet_poll_cleantx(struct receive_queue *rq)
1185 struct virtnet_info *vi = rq->vq->vdev->priv;
1186 unsigned int index = vq2rxq(rq->vq);
1187 struct send_queue *sq = &vi->sq[index];
1188 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
1190 if (!sq->napi.weight)
1193 if (__netif_tx_trylock(txq)) {
1194 free_old_xmit_skbs(sq);
1195 __netif_tx_unlock(txq);
1198 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1199 netif_tx_wake_queue(txq);
1202 static int virtnet_poll(struct napi_struct *napi, int budget)
1204 struct receive_queue *rq =
1205 container_of(napi, struct receive_queue, napi);
1206 unsigned int received;
1207 bool xdp_xmit = false;
1209 virtnet_poll_cleantx(rq);
1211 received = virtnet_receive(rq, budget, &xdp_xmit);
1213 /* Out of packets? */
1214 if (received < budget)
1215 virtqueue_napi_complete(napi, rq->vq, received);
1223 static int virtnet_open(struct net_device *dev)
1225 struct virtnet_info *vi = netdev_priv(dev);
1228 for (i = 0; i < vi->max_queue_pairs; i++) {
1229 if (i < vi->curr_queue_pairs)
1230 /* Make sure we have some buffers: if oom use wq. */
1231 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1232 schedule_delayed_work(&vi->refill, 0);
1233 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1234 virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
1240 static int virtnet_poll_tx(struct napi_struct *napi, int budget)
1242 struct send_queue *sq = container_of(napi, struct send_queue, napi);
1243 struct virtnet_info *vi = sq->vq->vdev->priv;
1244 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, vq2txq(sq->vq));
1246 __netif_tx_lock(txq, raw_smp_processor_id());
1247 free_old_xmit_skbs(sq);
1248 __netif_tx_unlock(txq);
1250 virtqueue_napi_complete(napi, sq->vq, 0);
1252 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1253 netif_tx_wake_queue(txq);
1258 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1260 struct virtio_net_hdr_mrg_rxbuf *hdr;
1261 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1262 struct virtnet_info *vi = sq->vq->vdev->priv;
1264 unsigned hdr_len = vi->hdr_len;
1267 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1269 can_push = vi->any_header_sg &&
1270 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1271 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1272 /* Even if we can, don't push here yet as this would skew
1273 * csum_start offset below. */
1275 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1277 hdr = skb_vnet_hdr(skb);
1279 if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1280 virtio_is_little_endian(vi->vdev), false))
1283 if (vi->mergeable_rx_bufs)
1284 hdr->num_buffers = 0;
1286 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1288 __skb_push(skb, hdr_len);
1289 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1290 if (unlikely(num_sg < 0))
1292 /* Pull header back to avoid skew in tx bytes calculations. */
1293 __skb_pull(skb, hdr_len);
1295 sg_set_buf(sq->sg, hdr, hdr_len);
1296 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
1297 if (unlikely(num_sg < 0))
1301 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1304 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1306 struct virtnet_info *vi = netdev_priv(dev);
1307 int qnum = skb_get_queue_mapping(skb);
1308 struct send_queue *sq = &vi->sq[qnum];
1310 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1311 bool kick = !skb->xmit_more;
1312 bool use_napi = sq->napi.weight;
1314 /* Free up any pending old buffers before queueing new ones. */
1315 free_old_xmit_skbs(sq);
1317 if (use_napi && kick)
1318 virtqueue_enable_cb_delayed(sq->vq);
1320 /* timestamp packet in software */
1321 skb_tx_timestamp(skb);
1323 /* Try to transmit */
1324 err = xmit_skb(sq, skb);
1326 /* This should not happen! */
1327 if (unlikely(err)) {
1328 dev->stats.tx_fifo_errors++;
1329 if (net_ratelimit())
1331 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
1332 dev->stats.tx_dropped++;
1333 dev_kfree_skb_any(skb);
1334 return NETDEV_TX_OK;
1337 /* Don't wait up for transmitted skbs to be freed. */
1343 /* If running out of space, stop queue to avoid getting packets that we
1344 * are then unable to transmit.
1345 * An alternative would be to force queuing layer to requeue the skb by
1346 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1347 * returned in a normal path of operation: it means that driver is not
1348 * maintaining the TX queue stop/start state properly, and causes
1349 * the stack to do a non-trivial amount of useless work.
1350 * Since most packets only take 1 or 2 ring slots, stopping the queue
1351 * early means 16 slots are typically wasted.
1353 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1354 netif_stop_subqueue(dev, qnum);
1356 unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1357 /* More just got used, free them then recheck. */
1358 free_old_xmit_skbs(sq);
1359 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1360 netif_start_subqueue(dev, qnum);
1361 virtqueue_disable_cb(sq->vq);
1366 if (kick || netif_xmit_stopped(txq))
1367 virtqueue_kick(sq->vq);
1369 return NETDEV_TX_OK;
1373 * Send command via the control virtqueue and check status. Commands
1374 * supported by the hypervisor, as indicated by feature bits, should
1375 * never fail unless improperly formatted.
1377 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1378 struct scatterlist *out)
1380 struct scatterlist *sgs[4], hdr, stat;
1381 unsigned out_num = 0, tmp;
1383 /* Caller should know better */
1384 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1386 vi->ctrl_status = ~0;
1387 vi->ctrl_hdr.class = class;
1388 vi->ctrl_hdr.cmd = cmd;
1390 sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr));
1391 sgs[out_num++] = &hdr;
1394 sgs[out_num++] = out;
1396 /* Add return status. */
1397 sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status));
1398 sgs[out_num] = &stat;
1400 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1401 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1403 if (unlikely(!virtqueue_kick(vi->cvq)))
1404 return vi->ctrl_status == VIRTIO_NET_OK;
1406 /* Spin for a response, the kick causes an ioport write, trapping
1407 * into the hypervisor, so the request should be handled immediately.
1409 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1410 !virtqueue_is_broken(vi->cvq))
1413 return vi->ctrl_status == VIRTIO_NET_OK;
1416 static int virtnet_set_mac_address(struct net_device *dev, void *p)
1418 struct virtnet_info *vi = netdev_priv(dev);
1419 struct virtio_device *vdev = vi->vdev;
1421 struct sockaddr *addr;
1422 struct scatterlist sg;
1424 addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
1428 ret = eth_prepare_mac_addr_change(dev, addr);
1432 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1433 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1434 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1435 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1436 dev_warn(&vdev->dev,
1437 "Failed to set mac address by vq command.\n");
1441 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1442 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1445 /* Naturally, this has an atomicity problem. */
1446 for (i = 0; i < dev->addr_len; i++)
1447 virtio_cwrite8(vdev,
1448 offsetof(struct virtio_net_config, mac) +
1449 i, addr->sa_data[i]);
1452 eth_commit_mac_addr_change(dev, p);
1460 static void virtnet_stats(struct net_device *dev,
1461 struct rtnl_link_stats64 *tot)
1463 struct virtnet_info *vi = netdev_priv(dev);
1467 for_each_possible_cpu(cpu) {
1468 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
1469 u64 tpackets, tbytes, rpackets, rbytes;
1472 start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
1473 tpackets = stats->tx_packets;
1474 tbytes = stats->tx_bytes;
1475 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
1478 start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
1479 rpackets = stats->rx_packets;
1480 rbytes = stats->rx_bytes;
1481 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
1483 tot->rx_packets += rpackets;
1484 tot->tx_packets += tpackets;
1485 tot->rx_bytes += rbytes;
1486 tot->tx_bytes += tbytes;
1489 tot->tx_dropped = dev->stats.tx_dropped;
1490 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1491 tot->rx_dropped = dev->stats.rx_dropped;
1492 tot->rx_length_errors = dev->stats.rx_length_errors;
1493 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1496 #ifdef CONFIG_NET_POLL_CONTROLLER
1497 static void virtnet_netpoll(struct net_device *dev)
1499 struct virtnet_info *vi = netdev_priv(dev);
1502 for (i = 0; i < vi->curr_queue_pairs; i++)
1503 napi_schedule(&vi->rq[i].napi);
1507 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1510 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1511 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1512 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1516 static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1518 struct scatterlist sg;
1519 struct net_device *dev = vi->dev;
1521 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1524 vi->ctrl_mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1525 sg_init_one(&sg, &vi->ctrl_mq, sizeof(vi->ctrl_mq));
1527 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1528 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1529 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1533 vi->curr_queue_pairs = queue_pairs;
1534 /* virtnet_open() will refill when device is going to up. */
1535 if (dev->flags & IFF_UP)
1536 schedule_delayed_work(&vi->refill, 0);
1542 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1547 err = _virtnet_set_queues(vi, queue_pairs);
1552 static int virtnet_close(struct net_device *dev)
1554 struct virtnet_info *vi = netdev_priv(dev);
1557 /* Make sure refill_work doesn't re-enable napi! */
1558 cancel_delayed_work_sync(&vi->refill);
1560 for (i = 0; i < vi->max_queue_pairs; i++) {
1561 napi_disable(&vi->rq[i].napi);
1562 virtnet_napi_tx_disable(&vi->sq[i].napi);
1568 static void virtnet_set_rx_mode(struct net_device *dev)
1570 struct virtnet_info *vi = netdev_priv(dev);
1571 struct scatterlist sg[2];
1572 struct virtio_net_ctrl_mac *mac_data;
1573 struct netdev_hw_addr *ha;
1579 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1580 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1583 vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0);
1584 vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1586 sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc));
1588 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1589 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1590 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1591 vi->ctrl_promisc ? "en" : "dis");
1593 sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti));
1595 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1596 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1597 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1598 vi->ctrl_allmulti ? "en" : "dis");
1600 uc_count = netdev_uc_count(dev);
1601 mc_count = netdev_mc_count(dev);
1602 /* MAC filter - use one buffer for both lists */
1603 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1604 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1609 sg_init_table(sg, 2);
1611 /* Store the unicast list and count in the front of the buffer */
1612 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1614 netdev_for_each_uc_addr(ha, dev)
1615 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1617 sg_set_buf(&sg[0], mac_data,
1618 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1620 /* multicast list and count fill the end */
1621 mac_data = (void *)&mac_data->macs[uc_count][0];
1623 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1625 netdev_for_each_mc_addr(ha, dev)
1626 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1628 sg_set_buf(&sg[1], mac_data,
1629 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1631 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1632 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1633 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1638 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1639 __be16 proto, u16 vid)
1641 struct virtnet_info *vi = netdev_priv(dev);
1642 struct scatterlist sg;
1645 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1647 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1648 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1649 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1653 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1654 __be16 proto, u16 vid)
1656 struct virtnet_info *vi = netdev_priv(dev);
1657 struct scatterlist sg;
1660 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1662 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1663 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1664 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1668 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1672 if (vi->affinity_hint_set) {
1673 for (i = 0; i < vi->max_queue_pairs; i++) {
1674 virtqueue_set_affinity(vi->rq[i].vq, -1);
1675 virtqueue_set_affinity(vi->sq[i].vq, -1);
1678 vi->affinity_hint_set = false;
1682 static void virtnet_set_affinity(struct virtnet_info *vi)
1687 /* In multiqueue mode, when the number of cpu is equal to the number of
1688 * queue pairs, we let the queue pairs to be private to one cpu by
1689 * setting the affinity hint to eliminate the contention.
1691 if (vi->curr_queue_pairs == 1 ||
1692 vi->max_queue_pairs != num_online_cpus()) {
1693 virtnet_clean_affinity(vi, -1);
1698 for_each_online_cpu(cpu) {
1699 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1700 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1701 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1705 vi->affinity_hint_set = true;
1708 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1710 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1712 virtnet_set_affinity(vi);
1716 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1718 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1720 virtnet_set_affinity(vi);
1724 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
1726 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1729 virtnet_clean_affinity(vi, cpu);
1733 static enum cpuhp_state virtionet_online;
1735 static int virtnet_cpu_notif_add(struct virtnet_info *vi)
1739 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
1742 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1746 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1750 static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
1752 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1753 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1757 static void virtnet_get_ringparam(struct net_device *dev,
1758 struct ethtool_ringparam *ring)
1760 struct virtnet_info *vi = netdev_priv(dev);
1762 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1763 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1764 ring->rx_pending = ring->rx_max_pending;
1765 ring->tx_pending = ring->tx_max_pending;
1769 static void virtnet_get_drvinfo(struct net_device *dev,
1770 struct ethtool_drvinfo *info)
1772 struct virtnet_info *vi = netdev_priv(dev);
1773 struct virtio_device *vdev = vi->vdev;
1775 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1776 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1777 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1781 /* TODO: Eliminate OOO packets during switching */
1782 static int virtnet_set_channels(struct net_device *dev,
1783 struct ethtool_channels *channels)
1785 struct virtnet_info *vi = netdev_priv(dev);
1786 u16 queue_pairs = channels->combined_count;
1789 /* We don't support separate rx/tx channels.
1790 * We don't allow setting 'other' channels.
1792 if (channels->rx_count || channels->tx_count || channels->other_count)
1795 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
1798 /* For now we don't support modifying channels while XDP is loaded
1799 * also when XDP is loaded all RX queues have XDP programs so we only
1800 * need to check a single RX queue.
1802 if (vi->rq[0].xdp_prog)
1806 err = _virtnet_set_queues(vi, queue_pairs);
1808 netif_set_real_num_tx_queues(dev, queue_pairs);
1809 netif_set_real_num_rx_queues(dev, queue_pairs);
1811 virtnet_set_affinity(vi);
1818 static void virtnet_get_channels(struct net_device *dev,
1819 struct ethtool_channels *channels)
1821 struct virtnet_info *vi = netdev_priv(dev);
1823 channels->combined_count = vi->curr_queue_pairs;
1824 channels->max_combined = vi->max_queue_pairs;
1825 channels->max_other = 0;
1826 channels->rx_count = 0;
1827 channels->tx_count = 0;
1828 channels->other_count = 0;
1831 /* Check if the user is trying to change anything besides speed/duplex */
1833 virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings *cmd)
1835 struct ethtool_link_ksettings diff1 = *cmd;
1836 struct ethtool_link_ksettings diff2 = {};
1838 /* cmd is always set so we need to clear it, validate the port type
1839 * and also without autonegotiation we can ignore advertising
1841 diff1.base.speed = 0;
1842 diff2.base.port = PORT_OTHER;
1843 ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
1844 diff1.base.duplex = 0;
1846 diff1.base.link_mode_masks_nwords = 0;
1848 return !memcmp(&diff1.base, &diff2.base, sizeof(diff1.base)) &&
1849 bitmap_empty(diff1.link_modes.supported,
1850 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
1851 bitmap_empty(diff1.link_modes.advertising,
1852 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
1853 bitmap_empty(diff1.link_modes.lp_advertising,
1854 __ETHTOOL_LINK_MODE_MASK_NBITS);
1857 static int virtnet_set_link_ksettings(struct net_device *dev,
1858 const struct ethtool_link_ksettings *cmd)
1860 struct virtnet_info *vi = netdev_priv(dev);
1863 speed = cmd->base.speed;
1864 /* don't allow custom speed and duplex */
1865 if (!ethtool_validate_speed(speed) ||
1866 !ethtool_validate_duplex(cmd->base.duplex) ||
1867 !virtnet_validate_ethtool_cmd(cmd))
1870 vi->duplex = cmd->base.duplex;
1875 static int virtnet_get_link_ksettings(struct net_device *dev,
1876 struct ethtool_link_ksettings *cmd)
1878 struct virtnet_info *vi = netdev_priv(dev);
1880 cmd->base.speed = vi->speed;
1881 cmd->base.duplex = vi->duplex;
1882 cmd->base.port = PORT_OTHER;
1887 static void virtnet_init_settings(struct net_device *dev)
1889 struct virtnet_info *vi = netdev_priv(dev);
1891 vi->speed = SPEED_UNKNOWN;
1892 vi->duplex = DUPLEX_UNKNOWN;
1895 static const struct ethtool_ops virtnet_ethtool_ops = {
1896 .get_drvinfo = virtnet_get_drvinfo,
1897 .get_link = ethtool_op_get_link,
1898 .get_ringparam = virtnet_get_ringparam,
1899 .set_channels = virtnet_set_channels,
1900 .get_channels = virtnet_get_channels,
1901 .get_ts_info = ethtool_op_get_ts_info,
1902 .get_link_ksettings = virtnet_get_link_ksettings,
1903 .set_link_ksettings = virtnet_set_link_ksettings,
1906 static void virtnet_freeze_down(struct virtio_device *vdev)
1908 struct virtnet_info *vi = vdev->priv;
1911 /* Make sure no work handler is accessing the device */
1912 flush_work(&vi->config_work);
1914 netif_device_detach(vi->dev);
1915 netif_tx_disable(vi->dev);
1916 cancel_delayed_work_sync(&vi->refill);
1918 if (netif_running(vi->dev)) {
1919 for (i = 0; i < vi->max_queue_pairs; i++) {
1920 napi_disable(&vi->rq[i].napi);
1921 virtnet_napi_tx_disable(&vi->sq[i].napi);
1926 static int init_vqs(struct virtnet_info *vi);
1928 static int virtnet_restore_up(struct virtio_device *vdev)
1930 struct virtnet_info *vi = vdev->priv;
1937 virtio_device_ready(vdev);
1939 if (netif_running(vi->dev)) {
1940 for (i = 0; i < vi->curr_queue_pairs; i++)
1941 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1942 schedule_delayed_work(&vi->refill, 0);
1944 for (i = 0; i < vi->max_queue_pairs; i++) {
1945 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1946 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
1951 netif_device_attach(vi->dev);
1955 static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
1957 struct scatterlist sg;
1958 vi->ctrl_offloads = cpu_to_virtio64(vi->vdev, offloads);
1960 sg_init_one(&sg, &vi->ctrl_offloads, sizeof(vi->ctrl_offloads));
1962 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
1963 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
1964 dev_warn(&vi->dev->dev, "Fail to set guest offload. \n");
1971 static int virtnet_clear_guest_offloads(struct virtnet_info *vi)
1975 if (!vi->guest_offloads)
1978 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))
1979 offloads = 1ULL << VIRTIO_NET_F_GUEST_CSUM;
1981 return virtnet_set_guest_offloads(vi, offloads);
1984 static int virtnet_restore_guest_offloads(struct virtnet_info *vi)
1986 u64 offloads = vi->guest_offloads;
1988 if (!vi->guest_offloads)
1990 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))
1991 offloads |= 1ULL << VIRTIO_NET_F_GUEST_CSUM;
1993 return virtnet_set_guest_offloads(vi, offloads);
1996 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
1997 struct netlink_ext_ack *extack)
1999 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
2000 struct virtnet_info *vi = netdev_priv(dev);
2001 struct bpf_prog *old_prog;
2002 u16 xdp_qp = 0, curr_qp;
2005 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)
2006 && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2007 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2008 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
2009 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO))) {
2010 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing LRO, disable LRO first");
2014 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
2015 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
2019 if (dev->mtu > max_sz) {
2020 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
2021 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
2025 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
2027 xdp_qp = nr_cpu_ids;
2029 /* XDP requires extra queues for XDP_TX */
2030 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
2031 NL_SET_ERR_MSG_MOD(extack, "Too few free TX rings available");
2032 netdev_warn(dev, "request %i queues but max is %i\n",
2033 curr_qp + xdp_qp, vi->max_queue_pairs);
2038 prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
2040 return PTR_ERR(prog);
2043 /* Make sure NAPI is not using any XDP TX queues for RX. */
2044 for (i = 0; i < vi->max_queue_pairs; i++)
2045 napi_disable(&vi->rq[i].napi);
2047 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
2048 err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
2051 vi->xdp_queue_pairs = xdp_qp;
2053 for (i = 0; i < vi->max_queue_pairs; i++) {
2054 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2055 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
2058 virtnet_clear_guest_offloads(vi);
2060 virtnet_restore_guest_offloads(vi);
2063 bpf_prog_put(old_prog);
2064 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2070 for (i = 0; i < vi->max_queue_pairs; i++)
2071 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2073 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
2077 static u32 virtnet_xdp_query(struct net_device *dev)
2079 struct virtnet_info *vi = netdev_priv(dev);
2080 const struct bpf_prog *xdp_prog;
2083 for (i = 0; i < vi->max_queue_pairs; i++) {
2084 xdp_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2086 return xdp_prog->aux->id;
2091 static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
2093 switch (xdp->command) {
2094 case XDP_SETUP_PROG:
2095 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
2096 case XDP_QUERY_PROG:
2097 xdp->prog_id = virtnet_xdp_query(dev);
2098 xdp->prog_attached = !!xdp->prog_id;
2105 static const struct net_device_ops virtnet_netdev = {
2106 .ndo_open = virtnet_open,
2107 .ndo_stop = virtnet_close,
2108 .ndo_start_xmit = start_xmit,
2109 .ndo_validate_addr = eth_validate_addr,
2110 .ndo_set_mac_address = virtnet_set_mac_address,
2111 .ndo_set_rx_mode = virtnet_set_rx_mode,
2112 .ndo_get_stats64 = virtnet_stats,
2113 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
2114 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
2115 #ifdef CONFIG_NET_POLL_CONTROLLER
2116 .ndo_poll_controller = virtnet_netpoll,
2118 .ndo_bpf = virtnet_xdp,
2119 .ndo_xdp_xmit = virtnet_xdp_xmit,
2120 .ndo_xdp_flush = virtnet_xdp_flush,
2121 .ndo_features_check = passthru_features_check,
2124 static void virtnet_config_changed_work(struct work_struct *work)
2126 struct virtnet_info *vi =
2127 container_of(work, struct virtnet_info, config_work);
2130 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
2131 struct virtio_net_config, status, &v) < 0)
2134 if (v & VIRTIO_NET_S_ANNOUNCE) {
2135 netdev_notify_peers(vi->dev);
2136 virtnet_ack_link_announce(vi);
2139 /* Ignore unknown (future) status bits */
2140 v &= VIRTIO_NET_S_LINK_UP;
2142 if (vi->status == v)
2147 if (vi->status & VIRTIO_NET_S_LINK_UP) {
2148 netif_carrier_on(vi->dev);
2149 netif_tx_wake_all_queues(vi->dev);
2151 netif_carrier_off(vi->dev);
2152 netif_tx_stop_all_queues(vi->dev);
2156 static void virtnet_config_changed(struct virtio_device *vdev)
2158 struct virtnet_info *vi = vdev->priv;
2160 schedule_work(&vi->config_work);
2163 static void virtnet_free_queues(struct virtnet_info *vi)
2167 for (i = 0; i < vi->max_queue_pairs; i++) {
2168 napi_hash_del(&vi->rq[i].napi);
2169 netif_napi_del(&vi->rq[i].napi);
2170 netif_napi_del(&vi->sq[i].napi);
2173 /* We called napi_hash_del() before netif_napi_del(),
2174 * we need to respect an RCU grace period before freeing vi->rq
2182 static void _free_receive_bufs(struct virtnet_info *vi)
2184 struct bpf_prog *old_prog;
2187 for (i = 0; i < vi->max_queue_pairs; i++) {
2188 while (vi->rq[i].pages)
2189 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
2191 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2192 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
2194 bpf_prog_put(old_prog);
2198 static void free_receive_bufs(struct virtnet_info *vi)
2201 _free_receive_bufs(vi);
2205 static void free_receive_page_frags(struct virtnet_info *vi)
2208 for (i = 0; i < vi->max_queue_pairs; i++)
2209 if (vi->rq[i].alloc_frag.page)
2210 put_page(vi->rq[i].alloc_frag.page);
2213 static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
2215 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
2217 else if (q < vi->curr_queue_pairs)
2223 static void free_unused_bufs(struct virtnet_info *vi)
2228 for (i = 0; i < vi->max_queue_pairs; i++) {
2229 struct virtqueue *vq = vi->sq[i].vq;
2230 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2231 if (!is_xdp_raw_buffer_queue(vi, i))
2234 put_page(virt_to_head_page(buf));
2238 for (i = 0; i < vi->max_queue_pairs; i++) {
2239 struct virtqueue *vq = vi->rq[i].vq;
2241 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2242 if (vi->mergeable_rx_bufs) {
2243 put_page(virt_to_head_page(buf));
2244 } else if (vi->big_packets) {
2245 give_pages(&vi->rq[i], buf);
2247 put_page(virt_to_head_page(buf));
2253 static void virtnet_del_vqs(struct virtnet_info *vi)
2255 struct virtio_device *vdev = vi->vdev;
2257 virtnet_clean_affinity(vi, -1);
2259 vdev->config->del_vqs(vdev);
2261 virtnet_free_queues(vi);
2264 /* How large should a single buffer be so a queue full of these can fit at
2265 * least one full packet?
2266 * Logic below assumes the mergeable buffer header is used.
2268 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
2270 const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2271 unsigned int rq_size = virtqueue_get_vring_size(vq);
2272 unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
2273 unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
2274 unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
2276 return max(max(min_buf_len, hdr_len) - hdr_len,
2277 (unsigned int)GOOD_PACKET_LEN);
2280 static int virtnet_find_vqs(struct virtnet_info *vi)
2282 vq_callback_t **callbacks;
2283 struct virtqueue **vqs;
2289 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2290 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2291 * possible control vq.
2293 total_vqs = vi->max_queue_pairs * 2 +
2294 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
2296 /* Allocate space for find_vqs parameters */
2297 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
2300 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
2303 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
2306 if (!vi->big_packets || vi->mergeable_rx_bufs) {
2307 ctx = kzalloc(total_vqs * sizeof(*ctx), GFP_KERNEL);
2314 /* Parameters for control virtqueue, if any */
2316 callbacks[total_vqs - 1] = NULL;
2317 names[total_vqs - 1] = "control";
2320 /* Allocate/initialize parameters for send/receive virtqueues */
2321 for (i = 0; i < vi->max_queue_pairs; i++) {
2322 callbacks[rxq2vq(i)] = skb_recv_done;
2323 callbacks[txq2vq(i)] = skb_xmit_done;
2324 sprintf(vi->rq[i].name, "input.%d", i);
2325 sprintf(vi->sq[i].name, "output.%d", i);
2326 names[rxq2vq(i)] = vi->rq[i].name;
2327 names[txq2vq(i)] = vi->sq[i].name;
2329 ctx[rxq2vq(i)] = true;
2332 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
2338 vi->cvq = vqs[total_vqs - 1];
2339 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
2340 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2343 for (i = 0; i < vi->max_queue_pairs; i++) {
2344 vi->rq[i].vq = vqs[rxq2vq(i)];
2345 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
2346 vi->sq[i].vq = vqs[txq2vq(i)];
2368 static int virtnet_alloc_queues(struct virtnet_info *vi)
2372 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
2375 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
2379 INIT_DELAYED_WORK(&vi->refill, refill_work);
2380 for (i = 0; i < vi->max_queue_pairs; i++) {
2381 vi->rq[i].pages = NULL;
2382 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2384 netif_tx_napi_add(vi->dev, &vi->sq[i].napi, virtnet_poll_tx,
2385 napi_tx ? napi_weight : 0);
2387 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2388 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2389 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2400 static int init_vqs(struct virtnet_info *vi)
2404 /* Allocate send & receive queues */
2405 ret = virtnet_alloc_queues(vi);
2409 ret = virtnet_find_vqs(vi);
2414 virtnet_set_affinity(vi);
2420 virtnet_free_queues(vi);
2426 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2429 struct virtnet_info *vi = netdev_priv(queue->dev);
2430 unsigned int queue_index = get_netdev_rx_queue_index(queue);
2431 struct ewma_pkt_len *avg;
2433 BUG_ON(queue_index >= vi->max_queue_pairs);
2434 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2435 return sprintf(buf, "%u\n",
2436 get_mergeable_buf_len(&vi->rq[queue_index], avg));
2439 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2440 __ATTR_RO(mergeable_rx_buffer_size);
2442 static struct attribute *virtio_net_mrg_rx_attrs[] = {
2443 &mergeable_rx_buffer_size_attribute.attr,
2447 static const struct attribute_group virtio_net_mrg_rx_group = {
2448 .name = "virtio_net",
2449 .attrs = virtio_net_mrg_rx_attrs
2453 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2455 const char *fname, const char *dname)
2457 if (!virtio_has_feature(vdev, fbit))
2460 dev_err(&vdev->dev, "device advertises feature %s but not %s",
2466 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2467 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2469 static bool virtnet_validate_features(struct virtio_device *vdev)
2471 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2472 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2473 "VIRTIO_NET_F_CTRL_VQ") ||
2474 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2475 "VIRTIO_NET_F_CTRL_VQ") ||
2476 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2477 "VIRTIO_NET_F_CTRL_VQ") ||
2478 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2479 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2480 "VIRTIO_NET_F_CTRL_VQ"))) {
2487 #define MIN_MTU ETH_MIN_MTU
2488 #define MAX_MTU ETH_MAX_MTU
2490 static int virtnet_validate(struct virtio_device *vdev)
2492 if (!vdev->config->get) {
2493 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2498 if (!virtnet_validate_features(vdev))
2501 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2502 int mtu = virtio_cread16(vdev,
2503 offsetof(struct virtio_net_config,
2506 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2512 static int virtnet_probe(struct virtio_device *vdev)
2515 struct net_device *dev;
2516 struct virtnet_info *vi;
2517 u16 max_queue_pairs;
2520 /* Find if host supports multiqueue virtio_net device */
2521 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2522 struct virtio_net_config,
2523 max_virtqueue_pairs, &max_queue_pairs);
2525 /* We need at least 2 queue's */
2526 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
2527 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
2528 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2529 max_queue_pairs = 1;
2531 /* Allocate ourselves a network device with room for our info */
2532 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
2536 /* Set up network device as normal. */
2537 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
2538 dev->netdev_ops = &virtnet_netdev;
2539 dev->features = NETIF_F_HIGHDMA;
2541 dev->ethtool_ops = &virtnet_ethtool_ops;
2542 SET_NETDEV_DEV(dev, &vdev->dev);
2544 /* Do we support "hardware" checksums? */
2545 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
2546 /* This opens up the world of extra features. */
2547 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2549 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2551 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
2552 dev->hw_features |= NETIF_F_TSO
2553 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
2555 /* Individual feature bits: what can host handle? */
2556 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
2557 dev->hw_features |= NETIF_F_TSO;
2558 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
2559 dev->hw_features |= NETIF_F_TSO6;
2560 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
2561 dev->hw_features |= NETIF_F_TSO_ECN;
2563 dev->features |= NETIF_F_GSO_ROBUST;
2566 dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
2567 /* (!csum && gso) case will be fixed by register_netdev() */
2569 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
2570 dev->features |= NETIF_F_RXCSUM;
2572 dev->vlan_features = dev->features;
2574 /* MTU range: 68 - 65535 */
2575 dev->min_mtu = MIN_MTU;
2576 dev->max_mtu = MAX_MTU;
2578 /* Configuration may specify what MAC to use. Otherwise random. */
2579 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
2580 virtio_cread_bytes(vdev,
2581 offsetof(struct virtio_net_config, mac),
2582 dev->dev_addr, dev->addr_len);
2584 eth_hw_addr_random(dev);
2586 /* Set up our device-specific information */
2587 vi = netdev_priv(dev);
2591 vi->stats = alloc_percpu(struct virtnet_stats);
2593 if (vi->stats == NULL)
2596 for_each_possible_cpu(i) {
2597 struct virtnet_stats *virtnet_stats;
2598 virtnet_stats = per_cpu_ptr(vi->stats, i);
2599 u64_stats_init(&virtnet_stats->tx_syncp);
2600 u64_stats_init(&virtnet_stats->rx_syncp);
2603 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
2605 /* If we can receive ANY GSO packets, we must allocate large ones. */
2606 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2607 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2608 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
2609 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
2610 vi->big_packets = true;
2612 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
2613 vi->mergeable_rx_bufs = true;
2615 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
2616 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2617 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2619 vi->hdr_len = sizeof(struct virtio_net_hdr);
2621 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
2622 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2623 vi->any_header_sg = true;
2625 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2628 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2629 mtu = virtio_cread16(vdev,
2630 offsetof(struct virtio_net_config,
2632 if (mtu < dev->min_mtu) {
2633 /* Should never trigger: MTU was previously validated
2634 * in virtnet_validate.
2636 dev_err(&vdev->dev, "device MTU appears to have changed "
2637 "it is now %d < %d", mtu, dev->min_mtu);
2644 /* TODO: size buffers correctly in this case. */
2645 if (dev->mtu > ETH_DATA_LEN)
2646 vi->big_packets = true;
2649 if (vi->any_header_sg)
2650 dev->needed_headroom = vi->hdr_len;
2652 /* Enable multiqueue by default */
2653 if (num_online_cpus() >= max_queue_pairs)
2654 vi->curr_queue_pairs = max_queue_pairs;
2656 vi->curr_queue_pairs = num_online_cpus();
2657 vi->max_queue_pairs = max_queue_pairs;
2659 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
2665 if (vi->mergeable_rx_bufs)
2666 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
2668 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
2669 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
2671 virtnet_init_settings(dev);
2673 err = register_netdev(dev);
2675 pr_debug("virtio_net: registering device failed\n");
2679 virtio_device_ready(vdev);
2681 err = virtnet_cpu_notif_add(vi);
2683 pr_debug("virtio_net: registering cpu notifier failed\n");
2684 goto free_unregister_netdev;
2687 virtnet_set_queues(vi, vi->curr_queue_pairs);
2689 /* Assume link up if device can't report link status,
2690 otherwise get link status from config. */
2691 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
2692 netif_carrier_off(dev);
2693 schedule_work(&vi->config_work);
2695 vi->status = VIRTIO_NET_S_LINK_UP;
2696 netif_carrier_on(dev);
2699 for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
2700 if (virtio_has_feature(vi->vdev, guest_offloads[i]))
2701 set_bit(guest_offloads[i], &vi->guest_offloads);
2703 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
2704 dev->name, max_queue_pairs);
2708 free_unregister_netdev:
2709 vi->vdev->config->reset(vdev);
2711 unregister_netdev(dev);
2713 cancel_delayed_work_sync(&vi->refill);
2714 free_receive_page_frags(vi);
2715 virtnet_del_vqs(vi);
2717 free_percpu(vi->stats);
2723 static void remove_vq_common(struct virtnet_info *vi)
2725 vi->vdev->config->reset(vi->vdev);
2727 /* Free unused buffers in both send and recv, if any. */
2728 free_unused_bufs(vi);
2730 free_receive_bufs(vi);
2732 free_receive_page_frags(vi);
2734 virtnet_del_vqs(vi);
2737 static void virtnet_remove(struct virtio_device *vdev)
2739 struct virtnet_info *vi = vdev->priv;
2741 virtnet_cpu_notif_remove(vi);
2743 /* Make sure no work handler is accessing the device. */
2744 flush_work(&vi->config_work);
2746 unregister_netdev(vi->dev);
2748 remove_vq_common(vi);
2750 free_percpu(vi->stats);
2751 free_netdev(vi->dev);
2754 static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
2756 struct virtnet_info *vi = vdev->priv;
2758 virtnet_cpu_notif_remove(vi);
2759 virtnet_freeze_down(vdev);
2760 remove_vq_common(vi);
2765 static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
2767 struct virtnet_info *vi = vdev->priv;
2770 err = virtnet_restore_up(vdev);
2773 virtnet_set_queues(vi, vi->curr_queue_pairs);
2775 err = virtnet_cpu_notif_add(vi);
2782 static struct virtio_device_id id_table[] = {
2783 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
2787 #define VIRTNET_FEATURES \
2788 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
2790 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
2791 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
2792 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
2793 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
2794 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
2795 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
2796 VIRTIO_NET_F_CTRL_MAC_ADDR, \
2797 VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS
2799 static unsigned int features[] = {
2803 static unsigned int features_legacy[] = {
2806 VIRTIO_F_ANY_LAYOUT,
2809 static struct virtio_driver virtio_net_driver = {
2810 .feature_table = features,
2811 .feature_table_size = ARRAY_SIZE(features),
2812 .feature_table_legacy = features_legacy,
2813 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
2814 .driver.name = KBUILD_MODNAME,
2815 .driver.owner = THIS_MODULE,
2816 .id_table = id_table,
2817 .validate = virtnet_validate,
2818 .probe = virtnet_probe,
2819 .remove = virtnet_remove,
2820 .config_changed = virtnet_config_changed,
2821 #ifdef CONFIG_PM_SLEEP
2822 .freeze = virtnet_freeze,
2823 .restore = virtnet_restore,
2827 static __init int virtio_net_driver_init(void)
2831 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
2833 virtnet_cpu_down_prep);
2836 virtionet_online = ret;
2837 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
2838 NULL, virtnet_cpu_dead);
2842 ret = register_virtio_driver(&virtio_net_driver);
2847 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2849 cpuhp_remove_multi_state(virtionet_online);
2853 module_init(virtio_net_driver_init);
2855 static __exit void virtio_net_driver_exit(void)
2857 unregister_virtio_driver(&virtio_net_driver);
2858 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2859 cpuhp_remove_multi_state(virtionet_online);
2861 module_exit(virtio_net_driver_exit);
2863 MODULE_DEVICE_TABLE(virtio, id_table);
2864 MODULE_DESCRIPTION("Virtio network driver");
2865 MODULE_LICENSE("GPL");