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 <net/route.h>
34 static int napi_weight = NAPI_POLL_WEIGHT;
35 module_param(napi_weight, int, 0444);
37 static bool csum = true, gso = true, napi_tx;
38 module_param(csum, bool, 0444);
39 module_param(gso, bool, 0444);
40 module_param(napi_tx, bool, 0644);
42 /* FIXME: MTU in config. */
43 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
44 #define GOOD_COPY_LEN 128
46 #define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
48 /* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
49 #define VIRTIO_XDP_HEADROOM 256
51 /* RX packet size EWMA. The average packet size is used to determine the packet
52 * buffer size when refilling RX rings. As the entire RX ring may be refilled
53 * at once, the weight is chosen so that the EWMA will be insensitive to short-
54 * term, transient changes in packet size.
56 DECLARE_EWMA(pkt_len, 0, 64)
58 #define VIRTNET_DRIVER_VERSION "1.0.0"
60 struct virtnet_stats {
61 struct u64_stats_sync tx_syncp;
62 struct u64_stats_sync rx_syncp;
70 /* Internal representation of a send virtqueue */
72 /* Virtqueue associated with this send _queue */
75 /* TX: fragments + linear part + virtio header */
76 struct scatterlist sg[MAX_SKB_FRAGS + 2];
78 /* Name of the send queue: output.$index */
81 struct napi_struct napi;
84 /* Internal representation of a receive virtqueue */
85 struct receive_queue {
86 /* Virtqueue associated with this receive_queue */
89 struct napi_struct napi;
91 struct bpf_prog __rcu *xdp_prog;
93 /* Chain pages by the private ptr. */
96 /* Average packet length for mergeable receive buffers. */
97 struct ewma_pkt_len mrg_avg_pkt_len;
99 /* Page frag for packet buffer allocation. */
100 struct page_frag alloc_frag;
102 /* RX: fragments + linear part + virtio header */
103 struct scatterlist sg[MAX_SKB_FRAGS + 2];
105 /* Min single buffer size for mergeable buffers case. */
106 unsigned int min_buf_len;
108 /* Name of this receive queue: input.$index */
112 struct virtnet_info {
113 struct virtio_device *vdev;
114 struct virtqueue *cvq;
115 struct net_device *dev;
116 struct send_queue *sq;
117 struct receive_queue *rq;
120 /* Max # of queue pairs supported by the device */
123 /* # of queue pairs currently used by the driver */
124 u16 curr_queue_pairs;
126 /* # of XDP queue pairs currently used by the driver */
129 /* I like... big packets and I cannot lie! */
132 /* Host will merge rx buffers for big packets (shake it! shake it!) */
133 bool mergeable_rx_bufs;
135 /* Has control virtqueue */
138 /* Host can handle any s/g split between our header and packet data */
141 /* Packet virtio header size */
144 /* Active statistics */
145 struct virtnet_stats __percpu *stats;
147 /* Work struct for refilling if we run low on memory. */
148 struct delayed_work refill;
150 /* Work struct for config space updates */
151 struct work_struct config_work;
153 /* Does the affinity hint is set for virtqueues? */
154 bool affinity_hint_set;
156 /* CPU hotplug instances for online & dead */
157 struct hlist_node node;
158 struct hlist_node node_dead;
160 /* Control VQ buffers: protected by the rtnl lock */
161 struct virtio_net_ctrl_hdr ctrl_hdr;
162 virtio_net_ctrl_ack ctrl_status;
163 struct virtio_net_ctrl_mq ctrl_mq;
168 /* Ethtool settings */
173 struct padded_vnet_hdr {
174 struct virtio_net_hdr_mrg_rxbuf hdr;
176 * hdr is in a separate sg buffer, and data sg buffer shares same page
177 * with this header sg. This padding makes next sg 16 byte aligned
183 /* Converting between virtqueue no. and kernel tx/rx queue no.
184 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
186 static int vq2txq(struct virtqueue *vq)
188 return (vq->index - 1) / 2;
191 static int txq2vq(int txq)
196 static int vq2rxq(struct virtqueue *vq)
198 return vq->index / 2;
201 static int rxq2vq(int rxq)
206 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
208 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
212 * private is used to chain pages for big packets, put the whole
213 * most recent used list in the beginning for reuse
215 static void give_pages(struct receive_queue *rq, struct page *page)
219 /* Find end of list, sew whole thing into vi->rq.pages. */
220 for (end = page; end->private; end = (struct page *)end->private);
221 end->private = (unsigned long)rq->pages;
225 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
227 struct page *p = rq->pages;
230 rq->pages = (struct page *)p->private;
231 /* clear private here, it is used to chain pages */
234 p = alloc_page(gfp_mask);
238 static void virtqueue_napi_schedule(struct napi_struct *napi,
239 struct virtqueue *vq)
241 if (napi_schedule_prep(napi)) {
242 virtqueue_disable_cb(vq);
243 __napi_schedule(napi);
247 static void virtqueue_napi_complete(struct napi_struct *napi,
248 struct virtqueue *vq, int processed)
252 opaque = virtqueue_enable_cb_prepare(vq);
253 if (napi_complete_done(napi, processed) &&
254 unlikely(virtqueue_poll(vq, opaque)))
255 virtqueue_napi_schedule(napi, vq);
258 static void skb_xmit_done(struct virtqueue *vq)
260 struct virtnet_info *vi = vq->vdev->priv;
261 struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
263 /* Suppress further interrupts. */
264 virtqueue_disable_cb(vq);
267 virtqueue_napi_schedule(napi, vq);
269 /* We were probably waiting for more output buffers. */
270 netif_wake_subqueue(vi->dev, vq2txq(vq));
273 /* Called from bottom half context */
274 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
275 struct receive_queue *rq,
276 struct page *page, unsigned int offset,
277 unsigned int len, unsigned int truesize)
280 struct virtio_net_hdr_mrg_rxbuf *hdr;
281 unsigned int copy, hdr_len, hdr_padded_len;
284 p = page_address(page) + offset;
286 /* copy small packet so we can reuse these pages for small data */
287 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
291 hdr = skb_vnet_hdr(skb);
293 hdr_len = vi->hdr_len;
294 if (vi->mergeable_rx_bufs)
295 hdr_padded_len = sizeof *hdr;
297 hdr_padded_len = sizeof(struct padded_vnet_hdr);
299 memcpy(hdr, p, hdr_len);
302 offset += hdr_padded_len;
306 if (copy > skb_tailroom(skb))
307 copy = skb_tailroom(skb);
308 memcpy(skb_put(skb, copy), p, copy);
313 if (vi->mergeable_rx_bufs) {
315 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
322 * Verify that we can indeed put this data into a skb.
323 * This is here to handle cases when the device erroneously
324 * tries to receive more than is possible. This is usually
325 * the case of a broken device.
327 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
328 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
332 BUG_ON(offset >= PAGE_SIZE);
334 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
335 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
336 frag_size, truesize);
338 page = (struct page *)page->private;
343 give_pages(rq, page);
348 static bool virtnet_xdp_xmit(struct virtnet_info *vi,
349 struct receive_queue *rq,
350 struct xdp_buff *xdp)
352 struct virtio_net_hdr_mrg_rxbuf *hdr;
354 struct send_queue *sq;
359 qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
362 /* Free up any pending old buffers before queueing new ones. */
363 while ((xdp_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) {
364 struct page *sent_page = virt_to_head_page(xdp_sent);
369 xdp->data -= vi->hdr_len;
370 /* Zero header and leave csum up to XDP layers */
372 memset(hdr, 0, vi->hdr_len);
374 sg_init_one(sq->sg, xdp->data, xdp->data_end - xdp->data);
376 err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp->data, GFP_ATOMIC);
378 struct page *page = virt_to_head_page(xdp->data);
384 virtqueue_kick(sq->vq);
388 static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
390 return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0;
393 static struct sk_buff *receive_small(struct net_device *dev,
394 struct virtnet_info *vi,
395 struct receive_queue *rq,
396 void *buf, unsigned int len)
399 struct bpf_prog *xdp_prog;
400 unsigned int xdp_headroom = virtnet_get_headroom(vi);
401 unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
402 unsigned int headroom = vi->hdr_len + header_offset;
403 unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
404 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
405 unsigned int delta = 0;
409 xdp_prog = rcu_dereference(rq->xdp_prog);
411 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
416 if (unlikely(hdr->hdr.gso_type || hdr->hdr.flags))
419 xdp.data_hard_start = buf + VIRTNET_RX_PAD + vi->hdr_len;
420 xdp.data = xdp.data_hard_start + xdp_headroom;
421 xdp.data_end = xdp.data + len;
422 orig_data = xdp.data;
423 act = bpf_prog_run_xdp(xdp_prog, &xdp);
427 /* Recalculate length in case bpf program changed it */
428 delta = orig_data - xdp.data;
431 if (unlikely(!virtnet_xdp_xmit(vi, rq, &xdp)))
432 trace_xdp_exception(vi->dev, xdp_prog, act);
436 bpf_warn_invalid_xdp_action(act);
438 trace_xdp_exception(vi->dev, xdp_prog, act);
445 skb = build_skb(buf, buflen);
447 put_page(virt_to_head_page(buf));
450 skb_reserve(skb, headroom - delta);
451 skb_put(skb, len + delta);
453 buf += header_offset;
454 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
455 } /* keep zeroed vnet hdr since packet was changed by bpf */
462 dev->stats.rx_dropped++;
463 put_page(virt_to_head_page(buf));
468 static struct sk_buff *receive_big(struct net_device *dev,
469 struct virtnet_info *vi,
470 struct receive_queue *rq,
474 struct page *page = buf;
475 struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);
483 dev->stats.rx_dropped++;
484 give_pages(rq, page);
488 /* The conditions to enable XDP should preclude the underlying device from
489 * sending packets across multiple buffers (num_buf > 1). However per spec
490 * it does not appear to be illegal to do so but rather just against convention.
491 * So in order to avoid making a system unresponsive the packets are pushed
492 * into a page and the XDP program is run. This will be extremely slow and we
493 * push a warning to the user to fix this as soon as possible. Fixing this may
494 * require resolving the underlying hardware to determine why multiple buffers
495 * are being received or simply loading the XDP program in the ingress stack
496 * after the skb is built because there is no advantage to running it here
499 static struct page *xdp_linearize_page(struct receive_queue *rq,
505 struct page *page = alloc_page(GFP_ATOMIC);
506 unsigned int page_off = VIRTIO_XDP_HEADROOM;
511 memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
519 buf = virtqueue_get_buf(rq->vq, &buflen);
523 p = virt_to_head_page(buf);
524 off = buf - page_address(p);
526 /* guard against a misconfigured or uncooperative backend that
527 * is sending packet larger than the MTU.
529 if ((page_off + buflen) > PAGE_SIZE) {
534 memcpy(page_address(page) + page_off,
535 page_address(p) + off, buflen);
540 /* Headroom does not contribute to packet length */
541 *len = page_off - VIRTIO_XDP_HEADROOM;
544 __free_pages(page, 0);
548 static struct sk_buff *receive_mergeable(struct net_device *dev,
549 struct virtnet_info *vi,
550 struct receive_queue *rq,
555 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
556 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
557 struct page *page = virt_to_head_page(buf);
558 int offset = buf - page_address(page);
559 struct sk_buff *head_skb, *curr_skb;
560 struct bpf_prog *xdp_prog;
561 unsigned int truesize;
566 xdp_prog = rcu_dereference(rq->xdp_prog);
568 struct page *xdp_page;
573 /* This happens when rx buffer size is underestimated */
574 if (unlikely(num_buf > 1)) {
575 /* linearize data for XDP */
576 xdp_page = xdp_linearize_page(rq, &num_buf,
580 offset = VIRTIO_XDP_HEADROOM;
585 /* Transient failure which in theory could occur if
586 * in-flight packets from before XDP was enabled reach
587 * the receive path after XDP is loaded. In practice I
588 * was not able to create this condition.
590 if (unlikely(hdr->hdr.gso_type))
593 /* Allow consuming headroom but reserve enough space to push
594 * the descriptor on if we get an XDP_TX return code.
596 data = page_address(xdp_page) + offset;
597 xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len;
598 xdp.data = data + vi->hdr_len;
599 xdp.data_end = xdp.data + (len - vi->hdr_len);
600 act = bpf_prog_run_xdp(xdp_prog, &xdp);
604 /* recalculate offset to account for any header
605 * adjustments. Note other cases do not build an
606 * skb and avoid using offset
609 page_address(xdp_page) - vi->hdr_len;
611 /* We can only create skb based on xdp_page. */
612 if (unlikely(xdp_page != page)) {
615 head_skb = page_to_skb(vi, rq, xdp_page,
616 offset, len, PAGE_SIZE);
617 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
622 if (unlikely(!virtnet_xdp_xmit(vi, rq, &xdp)))
623 trace_xdp_exception(vi->dev, xdp_prog, act);
624 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
625 if (unlikely(xdp_page != page))
630 bpf_warn_invalid_xdp_action(act);
632 trace_xdp_exception(vi->dev, xdp_prog, act);
634 if (unlikely(xdp_page != page))
635 __free_pages(xdp_page, 0);
636 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
642 if (unlikely(len > (unsigned long)ctx)) {
643 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
644 dev->name, len, (unsigned long)ctx);
645 dev->stats.rx_length_errors++;
648 truesize = (unsigned long)ctx;
649 head_skb = page_to_skb(vi, rq, page, offset, len, truesize);
652 if (unlikely(!curr_skb))
657 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
658 if (unlikely(!ctx)) {
659 pr_debug("%s: rx error: %d buffers out of %d missing\n",
661 virtio16_to_cpu(vi->vdev,
663 dev->stats.rx_length_errors++;
667 page = virt_to_head_page(buf);
668 if (unlikely(len > (unsigned long)ctx)) {
669 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
670 dev->name, len, (unsigned long)ctx);
671 dev->stats.rx_length_errors++;
674 truesize = (unsigned long)ctx;
676 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
677 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
678 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
682 if (curr_skb == head_skb)
683 skb_shinfo(curr_skb)->frag_list = nskb;
685 curr_skb->next = nskb;
687 head_skb->truesize += nskb->truesize;
690 if (curr_skb != head_skb) {
691 head_skb->data_len += len;
692 head_skb->len += len;
693 head_skb->truesize += truesize;
695 offset = buf - page_address(page);
696 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
698 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
701 skb_add_rx_frag(curr_skb, num_skb_frags, page,
702 offset, len, truesize);
706 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
714 buf = virtqueue_get_buf(rq->vq, &len);
715 if (unlikely(!buf)) {
716 pr_debug("%s: rx error: %d buffers missing\n",
718 dev->stats.rx_length_errors++;
721 page = virt_to_head_page(buf);
725 dev->stats.rx_dropped++;
726 dev_kfree_skb(head_skb);
731 static int receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
732 void *buf, unsigned int len, void **ctx)
734 struct net_device *dev = vi->dev;
736 struct virtio_net_hdr_mrg_rxbuf *hdr;
739 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
740 pr_debug("%s: short packet %i\n", dev->name, len);
741 dev->stats.rx_length_errors++;
742 if (vi->mergeable_rx_bufs) {
743 put_page(virt_to_head_page(buf));
744 } else if (vi->big_packets) {
747 put_page(virt_to_head_page(buf));
752 if (vi->mergeable_rx_bufs)
753 skb = receive_mergeable(dev, vi, rq, buf, ctx, len);
754 else if (vi->big_packets)
755 skb = receive_big(dev, vi, rq, buf, len);
757 skb = receive_small(dev, vi, rq, buf, len);
762 hdr = skb_vnet_hdr(skb);
766 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
767 skb->ip_summed = CHECKSUM_UNNECESSARY;
769 if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
770 virtio_is_little_endian(vi->vdev))) {
771 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
772 dev->name, hdr->hdr.gso_type,
777 skb->protocol = eth_type_trans(skb, dev);
778 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
779 ntohs(skb->protocol), skb->len, skb->pkt_type);
781 napi_gro_receive(&rq->napi, skb);
785 dev->stats.rx_frame_errors++;
790 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
793 struct page_frag *alloc_frag = &rq->alloc_frag;
795 unsigned int xdp_headroom = virtnet_get_headroom(vi);
796 int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
799 len = SKB_DATA_ALIGN(len) +
800 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
801 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
804 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
805 get_page(alloc_frag->page);
806 alloc_frag->offset += len;
807 sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
808 vi->hdr_len + GOOD_PACKET_LEN);
809 err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, buf, gfp);
811 put_page(virt_to_head_page(buf));
816 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
819 struct page *first, *list = NULL;
823 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
825 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
826 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
827 first = get_a_page(rq, gfp);
830 give_pages(rq, list);
833 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
835 /* chain new page in list head to match sg */
836 first->private = (unsigned long)list;
840 first = get_a_page(rq, gfp);
842 give_pages(rq, list);
845 p = page_address(first);
847 /* rq->sg[0], rq->sg[1] share the same page */
848 /* a separated rq->sg[0] for header - required in case !any_header_sg */
849 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
851 /* rq->sg[1] for data packet, from offset */
852 offset = sizeof(struct padded_vnet_hdr);
853 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
855 /* chain first in list head */
856 first->private = (unsigned long)list;
857 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
860 give_pages(rq, first);
865 static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
866 struct ewma_pkt_len *avg_pkt_len)
868 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
871 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
872 rq->min_buf_len - hdr_len, PAGE_SIZE - hdr_len);
873 return ALIGN(len, L1_CACHE_BYTES);
876 static int add_recvbuf_mergeable(struct virtnet_info *vi,
877 struct receive_queue *rq, gfp_t gfp)
879 struct page_frag *alloc_frag = &rq->alloc_frag;
880 unsigned int headroom = virtnet_get_headroom(vi);
884 unsigned int len, hole;
886 len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len);
887 if (unlikely(!skb_page_frag_refill(len + headroom, alloc_frag, gfp)))
890 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
891 buf += headroom; /* advance address leaving hole at front of pkt */
892 ctx = (void *)(unsigned long)len;
893 get_page(alloc_frag->page);
894 alloc_frag->offset += len + headroom;
895 hole = alloc_frag->size - alloc_frag->offset;
896 if (hole < len + headroom) {
897 /* To avoid internal fragmentation, if there is very likely not
898 * enough space for another buffer, add the remaining space to
899 * the current buffer. This extra space is not included in
900 * the truesize stored in ctx.
903 alloc_frag->offset += hole;
906 sg_init_one(rq->sg, buf, len);
907 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
909 put_page(virt_to_head_page(buf));
915 * Returns false if we couldn't fill entirely (OOM).
917 * Normally run in the receive path, but can also be run from ndo_open
918 * before we're receiving packets, or from refill_work which is
919 * careful to disable receiving (using napi_disable).
921 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
929 if (vi->mergeable_rx_bufs)
930 err = add_recvbuf_mergeable(vi, rq, gfp);
931 else if (vi->big_packets)
932 err = add_recvbuf_big(vi, rq, gfp);
934 err = add_recvbuf_small(vi, rq, gfp);
936 oom = err == -ENOMEM;
939 } while (rq->vq->num_free);
940 virtqueue_kick(rq->vq);
944 static void skb_recv_done(struct virtqueue *rvq)
946 struct virtnet_info *vi = rvq->vdev->priv;
947 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
949 virtqueue_napi_schedule(&rq->napi, rvq);
952 static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
956 /* If all buffers were filled by other side before we napi_enabled, we
957 * won't get another interrupt, so process any outstanding packets now.
958 * Call local_bh_enable after to trigger softIRQ processing.
961 virtqueue_napi_schedule(napi, vq);
965 static void virtnet_napi_tx_enable(struct virtnet_info *vi,
966 struct virtqueue *vq,
967 struct napi_struct *napi)
972 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
973 * enable the feature if this is likely affine with the transmit path.
975 if (!vi->affinity_hint_set) {
980 return virtnet_napi_enable(vq, napi);
983 static void virtnet_napi_tx_disable(struct napi_struct *napi)
989 static void refill_work(struct work_struct *work)
991 struct virtnet_info *vi =
992 container_of(work, struct virtnet_info, refill.work);
996 for (i = 0; i < vi->curr_queue_pairs; i++) {
997 struct receive_queue *rq = &vi->rq[i];
999 napi_disable(&rq->napi);
1000 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
1001 virtnet_napi_enable(rq->vq, &rq->napi);
1003 /* In theory, this can happen: if we don't get any buffers in
1004 * we will *never* try to fill again.
1007 schedule_delayed_work(&vi->refill, HZ/2);
1011 static int virtnet_receive(struct receive_queue *rq, int budget)
1013 struct virtnet_info *vi = rq->vq->vdev->priv;
1014 unsigned int len, received = 0, bytes = 0;
1016 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
1018 if (vi->mergeable_rx_bufs) {
1021 while (received < budget &&
1022 (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) {
1023 bytes += receive_buf(vi, rq, buf, len, ctx);
1027 while (received < budget &&
1028 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
1029 bytes += receive_buf(vi, rq, buf, len, NULL);
1034 if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
1035 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
1036 schedule_delayed_work(&vi->refill, 0);
1039 u64_stats_update_begin(&stats->rx_syncp);
1040 stats->rx_bytes += bytes;
1041 stats->rx_packets += received;
1042 u64_stats_update_end(&stats->rx_syncp);
1047 static void free_old_xmit_skbs(struct send_queue *sq)
1049 struct sk_buff *skb;
1051 struct virtnet_info *vi = sq->vq->vdev->priv;
1052 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
1053 unsigned int packets = 0;
1054 unsigned int bytes = 0;
1056 while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1057 pr_debug("Sent skb %p\n", skb);
1062 dev_kfree_skb_any(skb);
1065 /* Avoid overhead when no packets have been processed
1066 * happens when called speculatively from start_xmit.
1071 u64_stats_update_begin(&stats->tx_syncp);
1072 stats->tx_bytes += bytes;
1073 stats->tx_packets += packets;
1074 u64_stats_update_end(&stats->tx_syncp);
1077 static void virtnet_poll_cleantx(struct receive_queue *rq)
1079 struct virtnet_info *vi = rq->vq->vdev->priv;
1080 unsigned int index = vq2rxq(rq->vq);
1081 struct send_queue *sq = &vi->sq[index];
1082 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
1084 if (!sq->napi.weight)
1087 if (__netif_tx_trylock(txq)) {
1088 free_old_xmit_skbs(sq);
1089 __netif_tx_unlock(txq);
1092 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1093 netif_tx_wake_queue(txq);
1096 static int virtnet_poll(struct napi_struct *napi, int budget)
1098 struct receive_queue *rq =
1099 container_of(napi, struct receive_queue, napi);
1100 unsigned int received;
1102 virtnet_poll_cleantx(rq);
1104 received = virtnet_receive(rq, budget);
1106 /* Out of packets? */
1107 if (received < budget)
1108 virtqueue_napi_complete(napi, rq->vq, received);
1113 static int virtnet_open(struct net_device *dev)
1115 struct virtnet_info *vi = netdev_priv(dev);
1118 for (i = 0; i < vi->max_queue_pairs; i++) {
1119 if (i < vi->curr_queue_pairs)
1120 /* Make sure we have some buffers: if oom use wq. */
1121 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1122 schedule_delayed_work(&vi->refill, 0);
1123 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1124 virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
1130 static int virtnet_poll_tx(struct napi_struct *napi, int budget)
1132 struct send_queue *sq = container_of(napi, struct send_queue, napi);
1133 struct virtnet_info *vi = sq->vq->vdev->priv;
1134 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, vq2txq(sq->vq));
1136 __netif_tx_lock(txq, raw_smp_processor_id());
1137 free_old_xmit_skbs(sq);
1138 __netif_tx_unlock(txq);
1140 virtqueue_napi_complete(napi, sq->vq, 0);
1142 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1143 netif_tx_wake_queue(txq);
1148 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1150 struct virtio_net_hdr_mrg_rxbuf *hdr;
1151 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1152 struct virtnet_info *vi = sq->vq->vdev->priv;
1154 unsigned hdr_len = vi->hdr_len;
1157 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1159 can_push = vi->any_header_sg &&
1160 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1161 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1162 /* Even if we can, don't push here yet as this would skew
1163 * csum_start offset below. */
1165 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1167 hdr = skb_vnet_hdr(skb);
1169 if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1170 virtio_is_little_endian(vi->vdev), false))
1173 if (vi->mergeable_rx_bufs)
1174 hdr->num_buffers = 0;
1176 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1178 __skb_push(skb, hdr_len);
1179 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1180 /* Pull header back to avoid skew in tx bytes calculations. */
1181 __skb_pull(skb, hdr_len);
1183 sg_set_buf(sq->sg, hdr, hdr_len);
1184 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
1186 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1189 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1191 struct virtnet_info *vi = netdev_priv(dev);
1192 int qnum = skb_get_queue_mapping(skb);
1193 struct send_queue *sq = &vi->sq[qnum];
1195 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1196 bool kick = !skb->xmit_more;
1197 bool use_napi = sq->napi.weight;
1199 /* Free up any pending old buffers before queueing new ones. */
1200 free_old_xmit_skbs(sq);
1202 if (use_napi && kick)
1203 virtqueue_enable_cb_delayed(sq->vq);
1205 /* timestamp packet in software */
1206 skb_tx_timestamp(skb);
1208 /* Try to transmit */
1209 err = xmit_skb(sq, skb);
1211 /* This should not happen! */
1212 if (unlikely(err)) {
1213 dev->stats.tx_fifo_errors++;
1214 if (net_ratelimit())
1216 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
1217 dev->stats.tx_dropped++;
1218 dev_kfree_skb_any(skb);
1219 return NETDEV_TX_OK;
1222 /* Don't wait up for transmitted skbs to be freed. */
1228 /* If running out of space, stop queue to avoid getting packets that we
1229 * are then unable to transmit.
1230 * An alternative would be to force queuing layer to requeue the skb by
1231 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1232 * returned in a normal path of operation: it means that driver is not
1233 * maintaining the TX queue stop/start state properly, and causes
1234 * the stack to do a non-trivial amount of useless work.
1235 * Since most packets only take 1 or 2 ring slots, stopping the queue
1236 * early means 16 slots are typically wasted.
1238 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1239 netif_stop_subqueue(dev, qnum);
1241 unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1242 /* More just got used, free them then recheck. */
1243 free_old_xmit_skbs(sq);
1244 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1245 netif_start_subqueue(dev, qnum);
1246 virtqueue_disable_cb(sq->vq);
1251 if (kick || netif_xmit_stopped(txq))
1252 virtqueue_kick(sq->vq);
1254 return NETDEV_TX_OK;
1258 * Send command via the control virtqueue and check status. Commands
1259 * supported by the hypervisor, as indicated by feature bits, should
1260 * never fail unless improperly formatted.
1262 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1263 struct scatterlist *out)
1265 struct scatterlist *sgs[4], hdr, stat;
1266 unsigned out_num = 0, tmp;
1268 /* Caller should know better */
1269 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1271 vi->ctrl_status = ~0;
1272 vi->ctrl_hdr.class = class;
1273 vi->ctrl_hdr.cmd = cmd;
1275 sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr));
1276 sgs[out_num++] = &hdr;
1279 sgs[out_num++] = out;
1281 /* Add return status. */
1282 sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status));
1283 sgs[out_num] = &stat;
1285 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1286 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1288 if (unlikely(!virtqueue_kick(vi->cvq)))
1289 return vi->ctrl_status == VIRTIO_NET_OK;
1291 /* Spin for a response, the kick causes an ioport write, trapping
1292 * into the hypervisor, so the request should be handled immediately.
1294 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1295 !virtqueue_is_broken(vi->cvq))
1298 return vi->ctrl_status == VIRTIO_NET_OK;
1301 static int virtnet_set_mac_address(struct net_device *dev, void *p)
1303 struct virtnet_info *vi = netdev_priv(dev);
1304 struct virtio_device *vdev = vi->vdev;
1306 struct sockaddr *addr;
1307 struct scatterlist sg;
1309 addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
1313 ret = eth_prepare_mac_addr_change(dev, addr);
1317 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1318 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1319 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1320 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1321 dev_warn(&vdev->dev,
1322 "Failed to set mac address by vq command.\n");
1326 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1327 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1330 /* Naturally, this has an atomicity problem. */
1331 for (i = 0; i < dev->addr_len; i++)
1332 virtio_cwrite8(vdev,
1333 offsetof(struct virtio_net_config, mac) +
1334 i, addr->sa_data[i]);
1337 eth_commit_mac_addr_change(dev, p);
1345 static void virtnet_stats(struct net_device *dev,
1346 struct rtnl_link_stats64 *tot)
1348 struct virtnet_info *vi = netdev_priv(dev);
1352 for_each_possible_cpu(cpu) {
1353 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
1354 u64 tpackets, tbytes, rpackets, rbytes;
1357 start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
1358 tpackets = stats->tx_packets;
1359 tbytes = stats->tx_bytes;
1360 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
1363 start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
1364 rpackets = stats->rx_packets;
1365 rbytes = stats->rx_bytes;
1366 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
1368 tot->rx_packets += rpackets;
1369 tot->tx_packets += tpackets;
1370 tot->rx_bytes += rbytes;
1371 tot->tx_bytes += tbytes;
1374 tot->tx_dropped = dev->stats.tx_dropped;
1375 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1376 tot->rx_dropped = dev->stats.rx_dropped;
1377 tot->rx_length_errors = dev->stats.rx_length_errors;
1378 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1381 #ifdef CONFIG_NET_POLL_CONTROLLER
1382 static void virtnet_netpoll(struct net_device *dev)
1384 struct virtnet_info *vi = netdev_priv(dev);
1387 for (i = 0; i < vi->curr_queue_pairs; i++)
1388 napi_schedule(&vi->rq[i].napi);
1392 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1395 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1396 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1397 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1401 static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1403 struct scatterlist sg;
1404 struct net_device *dev = vi->dev;
1406 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1409 vi->ctrl_mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1410 sg_init_one(&sg, &vi->ctrl_mq, sizeof(vi->ctrl_mq));
1412 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1413 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1414 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1418 vi->curr_queue_pairs = queue_pairs;
1419 /* virtnet_open() will refill when device is going to up. */
1420 if (dev->flags & IFF_UP)
1421 schedule_delayed_work(&vi->refill, 0);
1427 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1432 err = _virtnet_set_queues(vi, queue_pairs);
1437 static int virtnet_close(struct net_device *dev)
1439 struct virtnet_info *vi = netdev_priv(dev);
1442 /* Make sure refill_work doesn't re-enable napi! */
1443 cancel_delayed_work_sync(&vi->refill);
1445 for (i = 0; i < vi->max_queue_pairs; i++) {
1446 napi_disable(&vi->rq[i].napi);
1447 virtnet_napi_tx_disable(&vi->sq[i].napi);
1453 static void virtnet_set_rx_mode(struct net_device *dev)
1455 struct virtnet_info *vi = netdev_priv(dev);
1456 struct scatterlist sg[2];
1457 struct virtio_net_ctrl_mac *mac_data;
1458 struct netdev_hw_addr *ha;
1464 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1465 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1468 vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0);
1469 vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1471 sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc));
1473 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1474 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1475 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1476 vi->ctrl_promisc ? "en" : "dis");
1478 sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti));
1480 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1481 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1482 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1483 vi->ctrl_allmulti ? "en" : "dis");
1485 uc_count = netdev_uc_count(dev);
1486 mc_count = netdev_mc_count(dev);
1487 /* MAC filter - use one buffer for both lists */
1488 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1489 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1494 sg_init_table(sg, 2);
1496 /* Store the unicast list and count in the front of the buffer */
1497 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1499 netdev_for_each_uc_addr(ha, dev)
1500 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1502 sg_set_buf(&sg[0], mac_data,
1503 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1505 /* multicast list and count fill the end */
1506 mac_data = (void *)&mac_data->macs[uc_count][0];
1508 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1510 netdev_for_each_mc_addr(ha, dev)
1511 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1513 sg_set_buf(&sg[1], mac_data,
1514 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1516 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1517 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1518 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1523 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1524 __be16 proto, u16 vid)
1526 struct virtnet_info *vi = netdev_priv(dev);
1527 struct scatterlist sg;
1530 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1532 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1533 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1534 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1538 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1539 __be16 proto, u16 vid)
1541 struct virtnet_info *vi = netdev_priv(dev);
1542 struct scatterlist sg;
1545 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1547 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1548 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1549 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1553 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1557 if (vi->affinity_hint_set) {
1558 for (i = 0; i < vi->max_queue_pairs; i++) {
1559 virtqueue_set_affinity(vi->rq[i].vq, -1);
1560 virtqueue_set_affinity(vi->sq[i].vq, -1);
1563 vi->affinity_hint_set = false;
1567 static void virtnet_set_affinity(struct virtnet_info *vi)
1572 /* In multiqueue mode, when the number of cpu is equal to the number of
1573 * queue pairs, we let the queue pairs to be private to one cpu by
1574 * setting the affinity hint to eliminate the contention.
1576 if (vi->curr_queue_pairs == 1 ||
1577 vi->max_queue_pairs != num_online_cpus()) {
1578 virtnet_clean_affinity(vi, -1);
1583 for_each_online_cpu(cpu) {
1584 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1585 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1586 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1590 vi->affinity_hint_set = true;
1593 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1595 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1597 virtnet_set_affinity(vi);
1601 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1603 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1605 virtnet_set_affinity(vi);
1609 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
1611 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1614 virtnet_clean_affinity(vi, cpu);
1618 static enum cpuhp_state virtionet_online;
1620 static int virtnet_cpu_notif_add(struct virtnet_info *vi)
1624 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
1627 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1631 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1635 static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
1637 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1638 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1642 static void virtnet_get_ringparam(struct net_device *dev,
1643 struct ethtool_ringparam *ring)
1645 struct virtnet_info *vi = netdev_priv(dev);
1647 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1648 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1649 ring->rx_pending = ring->rx_max_pending;
1650 ring->tx_pending = ring->tx_max_pending;
1654 static void virtnet_get_drvinfo(struct net_device *dev,
1655 struct ethtool_drvinfo *info)
1657 struct virtnet_info *vi = netdev_priv(dev);
1658 struct virtio_device *vdev = vi->vdev;
1660 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1661 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1662 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1666 /* TODO: Eliminate OOO packets during switching */
1667 static int virtnet_set_channels(struct net_device *dev,
1668 struct ethtool_channels *channels)
1670 struct virtnet_info *vi = netdev_priv(dev);
1671 u16 queue_pairs = channels->combined_count;
1674 /* We don't support separate rx/tx channels.
1675 * We don't allow setting 'other' channels.
1677 if (channels->rx_count || channels->tx_count || channels->other_count)
1680 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
1683 /* For now we don't support modifying channels while XDP is loaded
1684 * also when XDP is loaded all RX queues have XDP programs so we only
1685 * need to check a single RX queue.
1687 if (vi->rq[0].xdp_prog)
1691 err = _virtnet_set_queues(vi, queue_pairs);
1693 netif_set_real_num_tx_queues(dev, queue_pairs);
1694 netif_set_real_num_rx_queues(dev, queue_pairs);
1696 virtnet_set_affinity(vi);
1703 static void virtnet_get_channels(struct net_device *dev,
1704 struct ethtool_channels *channels)
1706 struct virtnet_info *vi = netdev_priv(dev);
1708 channels->combined_count = vi->curr_queue_pairs;
1709 channels->max_combined = vi->max_queue_pairs;
1710 channels->max_other = 0;
1711 channels->rx_count = 0;
1712 channels->tx_count = 0;
1713 channels->other_count = 0;
1716 /* Check if the user is trying to change anything besides speed/duplex */
1718 virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings *cmd)
1720 struct ethtool_link_ksettings diff1 = *cmd;
1721 struct ethtool_link_ksettings diff2 = {};
1723 /* cmd is always set so we need to clear it, validate the port type
1724 * and also without autonegotiation we can ignore advertising
1726 diff1.base.speed = 0;
1727 diff2.base.port = PORT_OTHER;
1728 ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
1729 diff1.base.duplex = 0;
1731 diff1.base.link_mode_masks_nwords = 0;
1733 return !memcmp(&diff1.base, &diff2.base, sizeof(diff1.base)) &&
1734 bitmap_empty(diff1.link_modes.supported,
1735 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
1736 bitmap_empty(diff1.link_modes.advertising,
1737 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
1738 bitmap_empty(diff1.link_modes.lp_advertising,
1739 __ETHTOOL_LINK_MODE_MASK_NBITS);
1742 static int virtnet_set_link_ksettings(struct net_device *dev,
1743 const struct ethtool_link_ksettings *cmd)
1745 struct virtnet_info *vi = netdev_priv(dev);
1748 speed = cmd->base.speed;
1749 /* don't allow custom speed and duplex */
1750 if (!ethtool_validate_speed(speed) ||
1751 !ethtool_validate_duplex(cmd->base.duplex) ||
1752 !virtnet_validate_ethtool_cmd(cmd))
1755 vi->duplex = cmd->base.duplex;
1760 static int virtnet_get_link_ksettings(struct net_device *dev,
1761 struct ethtool_link_ksettings *cmd)
1763 struct virtnet_info *vi = netdev_priv(dev);
1765 cmd->base.speed = vi->speed;
1766 cmd->base.duplex = vi->duplex;
1767 cmd->base.port = PORT_OTHER;
1772 static void virtnet_init_settings(struct net_device *dev)
1774 struct virtnet_info *vi = netdev_priv(dev);
1776 vi->speed = SPEED_UNKNOWN;
1777 vi->duplex = DUPLEX_UNKNOWN;
1780 static const struct ethtool_ops virtnet_ethtool_ops = {
1781 .get_drvinfo = virtnet_get_drvinfo,
1782 .get_link = ethtool_op_get_link,
1783 .get_ringparam = virtnet_get_ringparam,
1784 .set_channels = virtnet_set_channels,
1785 .get_channels = virtnet_get_channels,
1786 .get_ts_info = ethtool_op_get_ts_info,
1787 .get_link_ksettings = virtnet_get_link_ksettings,
1788 .set_link_ksettings = virtnet_set_link_ksettings,
1791 static void virtnet_freeze_down(struct virtio_device *vdev)
1793 struct virtnet_info *vi = vdev->priv;
1796 /* Make sure no work handler is accessing the device */
1797 flush_work(&vi->config_work);
1799 netif_device_detach(vi->dev);
1800 cancel_delayed_work_sync(&vi->refill);
1802 if (netif_running(vi->dev)) {
1803 for (i = 0; i < vi->max_queue_pairs; i++) {
1804 napi_disable(&vi->rq[i].napi);
1805 virtnet_napi_tx_disable(&vi->sq[i].napi);
1810 static int init_vqs(struct virtnet_info *vi);
1811 static void _remove_vq_common(struct virtnet_info *vi);
1813 static int virtnet_restore_up(struct virtio_device *vdev)
1815 struct virtnet_info *vi = vdev->priv;
1822 virtio_device_ready(vdev);
1824 if (netif_running(vi->dev)) {
1825 for (i = 0; i < vi->curr_queue_pairs; i++)
1826 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1827 schedule_delayed_work(&vi->refill, 0);
1829 for (i = 0; i < vi->max_queue_pairs; i++) {
1830 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1831 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
1836 netif_device_attach(vi->dev);
1840 static int virtnet_reset(struct virtnet_info *vi, int curr_qp, int xdp_qp)
1842 struct virtio_device *dev = vi->vdev;
1845 virtio_config_disable(dev);
1846 dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
1847 virtnet_freeze_down(dev);
1848 _remove_vq_common(vi);
1850 virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
1851 virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER);
1853 ret = virtio_finalize_features(dev);
1857 vi->xdp_queue_pairs = xdp_qp;
1858 ret = virtnet_restore_up(dev);
1861 ret = _virtnet_set_queues(vi, curr_qp);
1865 virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
1866 virtio_config_enable(dev);
1869 virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
1873 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
1874 struct netlink_ext_ack *extack)
1876 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
1877 struct virtnet_info *vi = netdev_priv(dev);
1878 struct bpf_prog *old_prog;
1879 u16 xdp_qp = 0, curr_qp;
1882 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1883 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1884 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
1885 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO)) {
1886 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing LRO, disable LRO first");
1890 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
1891 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
1895 if (dev->mtu > max_sz) {
1896 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
1897 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
1901 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
1903 xdp_qp = nr_cpu_ids;
1905 /* XDP requires extra queues for XDP_TX */
1906 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
1907 NL_SET_ERR_MSG_MOD(extack, "Too few free TX rings available");
1908 netdev_warn(dev, "request %i queues but max is %i\n",
1909 curr_qp + xdp_qp, vi->max_queue_pairs);
1914 prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
1916 return PTR_ERR(prog);
1919 /* Changing the headroom in buffers is a disruptive operation because
1920 * existing buffers must be flushed and reallocated. This will happen
1921 * when a xdp program is initially added or xdp is disabled by removing
1922 * the xdp program resulting in number of XDP queues changing.
1924 if (vi->xdp_queue_pairs != xdp_qp) {
1925 err = virtnet_reset(vi, curr_qp + xdp_qp, xdp_qp);
1927 dev_warn(&dev->dev, "XDP reset failure.\n");
1928 goto virtio_reset_err;
1932 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
1934 for (i = 0; i < vi->max_queue_pairs; i++) {
1935 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
1936 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
1938 bpf_prog_put(old_prog);
1944 /* On reset error do our best to unwind XDP changes inflight and return
1945 * error up to user space for resolution. The underlying reset hung on
1946 * us so not much we can do here.
1949 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
1953 static bool virtnet_xdp_query(struct net_device *dev)
1955 struct virtnet_info *vi = netdev_priv(dev);
1958 for (i = 0; i < vi->max_queue_pairs; i++) {
1959 if (vi->rq[i].xdp_prog)
1965 static int virtnet_xdp(struct net_device *dev, struct netdev_xdp *xdp)
1967 switch (xdp->command) {
1968 case XDP_SETUP_PROG:
1969 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
1970 case XDP_QUERY_PROG:
1971 xdp->prog_attached = virtnet_xdp_query(dev);
1978 static const struct net_device_ops virtnet_netdev = {
1979 .ndo_open = virtnet_open,
1980 .ndo_stop = virtnet_close,
1981 .ndo_start_xmit = start_xmit,
1982 .ndo_validate_addr = eth_validate_addr,
1983 .ndo_set_mac_address = virtnet_set_mac_address,
1984 .ndo_set_rx_mode = virtnet_set_rx_mode,
1985 .ndo_get_stats64 = virtnet_stats,
1986 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
1987 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
1988 #ifdef CONFIG_NET_POLL_CONTROLLER
1989 .ndo_poll_controller = virtnet_netpoll,
1991 .ndo_xdp = virtnet_xdp,
1994 static void virtnet_config_changed_work(struct work_struct *work)
1996 struct virtnet_info *vi =
1997 container_of(work, struct virtnet_info, config_work);
2000 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
2001 struct virtio_net_config, status, &v) < 0)
2004 if (v & VIRTIO_NET_S_ANNOUNCE) {
2005 netdev_notify_peers(vi->dev);
2006 virtnet_ack_link_announce(vi);
2009 /* Ignore unknown (future) status bits */
2010 v &= VIRTIO_NET_S_LINK_UP;
2012 if (vi->status == v)
2017 if (vi->status & VIRTIO_NET_S_LINK_UP) {
2018 netif_carrier_on(vi->dev);
2019 netif_tx_wake_all_queues(vi->dev);
2021 netif_carrier_off(vi->dev);
2022 netif_tx_stop_all_queues(vi->dev);
2026 static void virtnet_config_changed(struct virtio_device *vdev)
2028 struct virtnet_info *vi = vdev->priv;
2030 schedule_work(&vi->config_work);
2033 static void virtnet_free_queues(struct virtnet_info *vi)
2037 for (i = 0; i < vi->max_queue_pairs; i++) {
2038 napi_hash_del(&vi->rq[i].napi);
2039 netif_napi_del(&vi->rq[i].napi);
2040 netif_napi_del(&vi->sq[i].napi);
2043 /* We called napi_hash_del() before netif_napi_del(),
2044 * we need to respect an RCU grace period before freeing vi->rq
2052 static void _free_receive_bufs(struct virtnet_info *vi)
2054 struct bpf_prog *old_prog;
2057 for (i = 0; i < vi->max_queue_pairs; i++) {
2058 while (vi->rq[i].pages)
2059 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
2061 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2062 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
2064 bpf_prog_put(old_prog);
2068 static void free_receive_bufs(struct virtnet_info *vi)
2071 _free_receive_bufs(vi);
2075 static void free_receive_page_frags(struct virtnet_info *vi)
2078 for (i = 0; i < vi->max_queue_pairs; i++)
2079 if (vi->rq[i].alloc_frag.page)
2080 put_page(vi->rq[i].alloc_frag.page);
2083 static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
2085 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
2087 else if (q < vi->curr_queue_pairs)
2093 static void free_unused_bufs(struct virtnet_info *vi)
2098 for (i = 0; i < vi->max_queue_pairs; i++) {
2099 struct virtqueue *vq = vi->sq[i].vq;
2100 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2101 if (!is_xdp_raw_buffer_queue(vi, i))
2104 put_page(virt_to_head_page(buf));
2108 for (i = 0; i < vi->max_queue_pairs; i++) {
2109 struct virtqueue *vq = vi->rq[i].vq;
2111 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2112 if (vi->mergeable_rx_bufs) {
2113 put_page(virt_to_head_page(buf));
2114 } else if (vi->big_packets) {
2115 give_pages(&vi->rq[i], buf);
2117 put_page(virt_to_head_page(buf));
2123 static void virtnet_del_vqs(struct virtnet_info *vi)
2125 struct virtio_device *vdev = vi->vdev;
2127 virtnet_clean_affinity(vi, -1);
2129 vdev->config->del_vqs(vdev);
2131 virtnet_free_queues(vi);
2134 /* How large should a single buffer be so a queue full of these can fit at
2135 * least one full packet?
2136 * Logic below assumes the mergeable buffer header is used.
2138 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
2140 const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2141 unsigned int rq_size = virtqueue_get_vring_size(vq);
2142 unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
2143 unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
2144 unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
2146 return max(min_buf_len, hdr_len);
2149 static int virtnet_find_vqs(struct virtnet_info *vi)
2151 vq_callback_t **callbacks;
2152 struct virtqueue **vqs;
2158 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2159 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2160 * possible control vq.
2162 total_vqs = vi->max_queue_pairs * 2 +
2163 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
2165 /* Allocate space for find_vqs parameters */
2166 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
2169 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
2172 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
2175 if (vi->mergeable_rx_bufs) {
2176 ctx = kzalloc(total_vqs * sizeof(*ctx), GFP_KERNEL);
2183 /* Parameters for control virtqueue, if any */
2185 callbacks[total_vqs - 1] = NULL;
2186 names[total_vqs - 1] = "control";
2189 /* Allocate/initialize parameters for send/receive virtqueues */
2190 for (i = 0; i < vi->max_queue_pairs; i++) {
2191 callbacks[rxq2vq(i)] = skb_recv_done;
2192 callbacks[txq2vq(i)] = skb_xmit_done;
2193 sprintf(vi->rq[i].name, "input.%d", i);
2194 sprintf(vi->sq[i].name, "output.%d", i);
2195 names[rxq2vq(i)] = vi->rq[i].name;
2196 names[txq2vq(i)] = vi->sq[i].name;
2198 ctx[rxq2vq(i)] = true;
2201 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
2207 vi->cvq = vqs[total_vqs - 1];
2208 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
2209 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2212 for (i = 0; i < vi->max_queue_pairs; i++) {
2213 vi->rq[i].vq = vqs[rxq2vq(i)];
2214 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
2215 vi->sq[i].vq = vqs[txq2vq(i)];
2236 static int virtnet_alloc_queues(struct virtnet_info *vi)
2240 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
2243 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
2247 INIT_DELAYED_WORK(&vi->refill, refill_work);
2248 for (i = 0; i < vi->max_queue_pairs; i++) {
2249 vi->rq[i].pages = NULL;
2250 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2252 netif_tx_napi_add(vi->dev, &vi->sq[i].napi, virtnet_poll_tx,
2253 napi_tx ? napi_weight : 0);
2255 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2256 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2257 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2268 static int init_vqs(struct virtnet_info *vi)
2272 /* Allocate send & receive queues */
2273 ret = virtnet_alloc_queues(vi);
2277 ret = virtnet_find_vqs(vi);
2282 virtnet_set_affinity(vi);
2288 virtnet_free_queues(vi);
2294 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2295 struct rx_queue_attribute *attribute, char *buf)
2297 struct virtnet_info *vi = netdev_priv(queue->dev);
2298 unsigned int queue_index = get_netdev_rx_queue_index(queue);
2299 struct ewma_pkt_len *avg;
2301 BUG_ON(queue_index >= vi->max_queue_pairs);
2302 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2303 return sprintf(buf, "%u\n",
2304 get_mergeable_buf_len(&vi->rq[queue_index], avg));
2307 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2308 __ATTR_RO(mergeable_rx_buffer_size);
2310 static struct attribute *virtio_net_mrg_rx_attrs[] = {
2311 &mergeable_rx_buffer_size_attribute.attr,
2315 static const struct attribute_group virtio_net_mrg_rx_group = {
2316 .name = "virtio_net",
2317 .attrs = virtio_net_mrg_rx_attrs
2321 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2323 const char *fname, const char *dname)
2325 if (!virtio_has_feature(vdev, fbit))
2328 dev_err(&vdev->dev, "device advertises feature %s but not %s",
2334 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2335 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2337 static bool virtnet_validate_features(struct virtio_device *vdev)
2339 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2340 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2341 "VIRTIO_NET_F_CTRL_VQ") ||
2342 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2343 "VIRTIO_NET_F_CTRL_VQ") ||
2344 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2345 "VIRTIO_NET_F_CTRL_VQ") ||
2346 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2347 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2348 "VIRTIO_NET_F_CTRL_VQ"))) {
2355 #define MIN_MTU ETH_MIN_MTU
2356 #define MAX_MTU ETH_MAX_MTU
2358 static int virtnet_validate(struct virtio_device *vdev)
2360 if (!vdev->config->get) {
2361 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2366 if (!virtnet_validate_features(vdev))
2369 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2370 int mtu = virtio_cread16(vdev,
2371 offsetof(struct virtio_net_config,
2374 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2380 static int virtnet_probe(struct virtio_device *vdev)
2383 struct net_device *dev;
2384 struct virtnet_info *vi;
2385 u16 max_queue_pairs;
2388 /* Find if host supports multiqueue virtio_net device */
2389 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2390 struct virtio_net_config,
2391 max_virtqueue_pairs, &max_queue_pairs);
2393 /* We need at least 2 queue's */
2394 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
2395 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
2396 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2397 max_queue_pairs = 1;
2399 /* Allocate ourselves a network device with room for our info */
2400 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
2404 /* Set up network device as normal. */
2405 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
2406 dev->netdev_ops = &virtnet_netdev;
2407 dev->features = NETIF_F_HIGHDMA;
2409 dev->ethtool_ops = &virtnet_ethtool_ops;
2410 SET_NETDEV_DEV(dev, &vdev->dev);
2412 /* Do we support "hardware" checksums? */
2413 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
2414 /* This opens up the world of extra features. */
2415 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2417 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2419 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
2420 dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
2421 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
2423 /* Individual feature bits: what can host handle? */
2424 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
2425 dev->hw_features |= NETIF_F_TSO;
2426 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
2427 dev->hw_features |= NETIF_F_TSO6;
2428 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
2429 dev->hw_features |= NETIF_F_TSO_ECN;
2430 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
2431 dev->hw_features |= NETIF_F_UFO;
2433 dev->features |= NETIF_F_GSO_ROBUST;
2436 dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
2437 /* (!csum && gso) case will be fixed by register_netdev() */
2439 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
2440 dev->features |= NETIF_F_RXCSUM;
2442 dev->vlan_features = dev->features;
2444 /* MTU range: 68 - 65535 */
2445 dev->min_mtu = MIN_MTU;
2446 dev->max_mtu = MAX_MTU;
2448 /* Configuration may specify what MAC to use. Otherwise random. */
2449 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
2450 virtio_cread_bytes(vdev,
2451 offsetof(struct virtio_net_config, mac),
2452 dev->dev_addr, dev->addr_len);
2454 eth_hw_addr_random(dev);
2456 /* Set up our device-specific information */
2457 vi = netdev_priv(dev);
2461 vi->stats = alloc_percpu(struct virtnet_stats);
2463 if (vi->stats == NULL)
2466 for_each_possible_cpu(i) {
2467 struct virtnet_stats *virtnet_stats;
2468 virtnet_stats = per_cpu_ptr(vi->stats, i);
2469 u64_stats_init(&virtnet_stats->tx_syncp);
2470 u64_stats_init(&virtnet_stats->rx_syncp);
2473 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
2475 /* If we can receive ANY GSO packets, we must allocate large ones. */
2476 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2477 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2478 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
2479 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
2480 vi->big_packets = true;
2482 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
2483 vi->mergeable_rx_bufs = true;
2485 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
2486 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2487 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2489 vi->hdr_len = sizeof(struct virtio_net_hdr);
2491 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
2492 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2493 vi->any_header_sg = true;
2495 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2498 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2499 mtu = virtio_cread16(vdev,
2500 offsetof(struct virtio_net_config,
2502 if (mtu < dev->min_mtu) {
2503 /* Should never trigger: MTU was previously validated
2504 * in virtnet_validate.
2506 dev_err(&vdev->dev, "device MTU appears to have changed "
2507 "it is now %d < %d", mtu, dev->min_mtu);
2514 /* TODO: size buffers correctly in this case. */
2515 if (dev->mtu > ETH_DATA_LEN)
2516 vi->big_packets = true;
2519 if (vi->any_header_sg)
2520 dev->needed_headroom = vi->hdr_len;
2522 /* Enable multiqueue by default */
2523 if (num_online_cpus() >= max_queue_pairs)
2524 vi->curr_queue_pairs = max_queue_pairs;
2526 vi->curr_queue_pairs = num_online_cpus();
2527 vi->max_queue_pairs = max_queue_pairs;
2529 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
2535 if (vi->mergeable_rx_bufs)
2536 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
2538 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
2539 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
2541 virtnet_init_settings(dev);
2543 err = register_netdev(dev);
2545 pr_debug("virtio_net: registering device failed\n");
2549 virtio_device_ready(vdev);
2551 err = virtnet_cpu_notif_add(vi);
2553 pr_debug("virtio_net: registering cpu notifier failed\n");
2554 goto free_unregister_netdev;
2557 virtnet_set_queues(vi, vi->curr_queue_pairs);
2559 /* Assume link up if device can't report link status,
2560 otherwise get link status from config. */
2561 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
2562 netif_carrier_off(dev);
2563 schedule_work(&vi->config_work);
2565 vi->status = VIRTIO_NET_S_LINK_UP;
2566 netif_carrier_on(dev);
2569 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
2570 dev->name, max_queue_pairs);
2574 free_unregister_netdev:
2575 vi->vdev->config->reset(vdev);
2577 unregister_netdev(dev);
2579 cancel_delayed_work_sync(&vi->refill);
2580 free_receive_page_frags(vi);
2581 virtnet_del_vqs(vi);
2583 free_percpu(vi->stats);
2589 static void _remove_vq_common(struct virtnet_info *vi)
2591 vi->vdev->config->reset(vi->vdev);
2592 free_unused_bufs(vi);
2593 _free_receive_bufs(vi);
2594 free_receive_page_frags(vi);
2595 virtnet_del_vqs(vi);
2598 static void remove_vq_common(struct virtnet_info *vi)
2600 vi->vdev->config->reset(vi->vdev);
2602 /* Free unused buffers in both send and recv, if any. */
2603 free_unused_bufs(vi);
2605 free_receive_bufs(vi);
2607 free_receive_page_frags(vi);
2609 virtnet_del_vqs(vi);
2612 static void virtnet_remove(struct virtio_device *vdev)
2614 struct virtnet_info *vi = vdev->priv;
2616 virtnet_cpu_notif_remove(vi);
2618 /* Make sure no work handler is accessing the device. */
2619 flush_work(&vi->config_work);
2621 unregister_netdev(vi->dev);
2623 remove_vq_common(vi);
2625 free_percpu(vi->stats);
2626 free_netdev(vi->dev);
2629 #ifdef CONFIG_PM_SLEEP
2630 static int virtnet_freeze(struct virtio_device *vdev)
2632 struct virtnet_info *vi = vdev->priv;
2634 virtnet_cpu_notif_remove(vi);
2635 virtnet_freeze_down(vdev);
2636 remove_vq_common(vi);
2641 static int virtnet_restore(struct virtio_device *vdev)
2643 struct virtnet_info *vi = vdev->priv;
2646 err = virtnet_restore_up(vdev);
2649 virtnet_set_queues(vi, vi->curr_queue_pairs);
2651 err = virtnet_cpu_notif_add(vi);
2659 static struct virtio_device_id id_table[] = {
2660 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
2664 #define VIRTNET_FEATURES \
2665 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
2667 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
2668 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
2669 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
2670 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
2671 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
2672 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
2673 VIRTIO_NET_F_CTRL_MAC_ADDR, \
2676 static unsigned int features[] = {
2680 static unsigned int features_legacy[] = {
2683 VIRTIO_F_ANY_LAYOUT,
2686 static struct virtio_driver virtio_net_driver = {
2687 .feature_table = features,
2688 .feature_table_size = ARRAY_SIZE(features),
2689 .feature_table_legacy = features_legacy,
2690 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
2691 .driver.name = KBUILD_MODNAME,
2692 .driver.owner = THIS_MODULE,
2693 .id_table = id_table,
2694 .validate = virtnet_validate,
2695 .probe = virtnet_probe,
2696 .remove = virtnet_remove,
2697 .config_changed = virtnet_config_changed,
2698 #ifdef CONFIG_PM_SLEEP
2699 .freeze = virtnet_freeze,
2700 .restore = virtnet_restore,
2704 static __init int virtio_net_driver_init(void)
2708 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
2710 virtnet_cpu_down_prep);
2713 virtionet_online = ret;
2714 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
2715 NULL, virtnet_cpu_dead);
2719 ret = register_virtio_driver(&virtio_net_driver);
2724 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2726 cpuhp_remove_multi_state(virtionet_online);
2730 module_init(virtio_net_driver_init);
2732 static __exit void virtio_net_driver_exit(void)
2734 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2735 cpuhp_remove_multi_state(virtionet_online);
2736 unregister_virtio_driver(&virtio_net_driver);
2738 module_exit(virtio_net_driver_exit);
2740 MODULE_DEVICE_TABLE(virtio, id_table);
2741 MODULE_DESCRIPTION("Virtio network driver");
2742 MODULE_LICENSE("GPL");