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 skb_put_data(skb, 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, 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 if (unlikely(num_sg < 0))
1182 /* Pull header back to avoid skew in tx bytes calculations. */
1183 __skb_pull(skb, hdr_len);
1185 sg_set_buf(sq->sg, hdr, hdr_len);
1186 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
1187 if (unlikely(num_sg < 0))
1191 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1194 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1196 struct virtnet_info *vi = netdev_priv(dev);
1197 int qnum = skb_get_queue_mapping(skb);
1198 struct send_queue *sq = &vi->sq[qnum];
1200 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1201 bool kick = !skb->xmit_more;
1202 bool use_napi = sq->napi.weight;
1204 /* Free up any pending old buffers before queueing new ones. */
1205 free_old_xmit_skbs(sq);
1207 if (use_napi && kick)
1208 virtqueue_enable_cb_delayed(sq->vq);
1210 /* timestamp packet in software */
1211 skb_tx_timestamp(skb);
1213 /* Try to transmit */
1214 err = xmit_skb(sq, skb);
1216 /* This should not happen! */
1217 if (unlikely(err)) {
1218 dev->stats.tx_fifo_errors++;
1219 if (net_ratelimit())
1221 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
1222 dev->stats.tx_dropped++;
1223 dev_kfree_skb_any(skb);
1224 return NETDEV_TX_OK;
1227 /* Don't wait up for transmitted skbs to be freed. */
1233 /* If running out of space, stop queue to avoid getting packets that we
1234 * are then unable to transmit.
1235 * An alternative would be to force queuing layer to requeue the skb by
1236 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1237 * returned in a normal path of operation: it means that driver is not
1238 * maintaining the TX queue stop/start state properly, and causes
1239 * the stack to do a non-trivial amount of useless work.
1240 * Since most packets only take 1 or 2 ring slots, stopping the queue
1241 * early means 16 slots are typically wasted.
1243 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1244 netif_stop_subqueue(dev, qnum);
1246 unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1247 /* More just got used, free them then recheck. */
1248 free_old_xmit_skbs(sq);
1249 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1250 netif_start_subqueue(dev, qnum);
1251 virtqueue_disable_cb(sq->vq);
1256 if (kick || netif_xmit_stopped(txq))
1257 virtqueue_kick(sq->vq);
1259 return NETDEV_TX_OK;
1263 * Send command via the control virtqueue and check status. Commands
1264 * supported by the hypervisor, as indicated by feature bits, should
1265 * never fail unless improperly formatted.
1267 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1268 struct scatterlist *out)
1270 struct scatterlist *sgs[4], hdr, stat;
1271 unsigned out_num = 0, tmp;
1273 /* Caller should know better */
1274 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1276 vi->ctrl_status = ~0;
1277 vi->ctrl_hdr.class = class;
1278 vi->ctrl_hdr.cmd = cmd;
1280 sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr));
1281 sgs[out_num++] = &hdr;
1284 sgs[out_num++] = out;
1286 /* Add return status. */
1287 sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status));
1288 sgs[out_num] = &stat;
1290 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1291 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1293 if (unlikely(!virtqueue_kick(vi->cvq)))
1294 return vi->ctrl_status == VIRTIO_NET_OK;
1296 /* Spin for a response, the kick causes an ioport write, trapping
1297 * into the hypervisor, so the request should be handled immediately.
1299 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1300 !virtqueue_is_broken(vi->cvq))
1303 return vi->ctrl_status == VIRTIO_NET_OK;
1306 static int virtnet_set_mac_address(struct net_device *dev, void *p)
1308 struct virtnet_info *vi = netdev_priv(dev);
1309 struct virtio_device *vdev = vi->vdev;
1311 struct sockaddr *addr;
1312 struct scatterlist sg;
1314 addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
1318 ret = eth_prepare_mac_addr_change(dev, addr);
1322 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1323 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1324 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1325 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1326 dev_warn(&vdev->dev,
1327 "Failed to set mac address by vq command.\n");
1331 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1332 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1335 /* Naturally, this has an atomicity problem. */
1336 for (i = 0; i < dev->addr_len; i++)
1337 virtio_cwrite8(vdev,
1338 offsetof(struct virtio_net_config, mac) +
1339 i, addr->sa_data[i]);
1342 eth_commit_mac_addr_change(dev, p);
1350 static void virtnet_stats(struct net_device *dev,
1351 struct rtnl_link_stats64 *tot)
1353 struct virtnet_info *vi = netdev_priv(dev);
1357 for_each_possible_cpu(cpu) {
1358 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
1359 u64 tpackets, tbytes, rpackets, rbytes;
1362 start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
1363 tpackets = stats->tx_packets;
1364 tbytes = stats->tx_bytes;
1365 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
1368 start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
1369 rpackets = stats->rx_packets;
1370 rbytes = stats->rx_bytes;
1371 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
1373 tot->rx_packets += rpackets;
1374 tot->tx_packets += tpackets;
1375 tot->rx_bytes += rbytes;
1376 tot->tx_bytes += tbytes;
1379 tot->tx_dropped = dev->stats.tx_dropped;
1380 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1381 tot->rx_dropped = dev->stats.rx_dropped;
1382 tot->rx_length_errors = dev->stats.rx_length_errors;
1383 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1386 #ifdef CONFIG_NET_POLL_CONTROLLER
1387 static void virtnet_netpoll(struct net_device *dev)
1389 struct virtnet_info *vi = netdev_priv(dev);
1392 for (i = 0; i < vi->curr_queue_pairs; i++)
1393 napi_schedule(&vi->rq[i].napi);
1397 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1400 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1401 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1402 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1406 static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1408 struct scatterlist sg;
1409 struct net_device *dev = vi->dev;
1411 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1414 vi->ctrl_mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1415 sg_init_one(&sg, &vi->ctrl_mq, sizeof(vi->ctrl_mq));
1417 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1418 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1419 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1423 vi->curr_queue_pairs = queue_pairs;
1424 /* virtnet_open() will refill when device is going to up. */
1425 if (dev->flags & IFF_UP)
1426 schedule_delayed_work(&vi->refill, 0);
1432 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1437 err = _virtnet_set_queues(vi, queue_pairs);
1442 static int virtnet_close(struct net_device *dev)
1444 struct virtnet_info *vi = netdev_priv(dev);
1447 /* Make sure refill_work doesn't re-enable napi! */
1448 cancel_delayed_work_sync(&vi->refill);
1450 for (i = 0; i < vi->max_queue_pairs; i++) {
1451 napi_disable(&vi->rq[i].napi);
1452 virtnet_napi_tx_disable(&vi->sq[i].napi);
1458 static void virtnet_set_rx_mode(struct net_device *dev)
1460 struct virtnet_info *vi = netdev_priv(dev);
1461 struct scatterlist sg[2];
1462 struct virtio_net_ctrl_mac *mac_data;
1463 struct netdev_hw_addr *ha;
1469 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1470 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1473 vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0);
1474 vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1476 sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc));
1478 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1479 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1480 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1481 vi->ctrl_promisc ? "en" : "dis");
1483 sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti));
1485 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1486 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1487 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1488 vi->ctrl_allmulti ? "en" : "dis");
1490 uc_count = netdev_uc_count(dev);
1491 mc_count = netdev_mc_count(dev);
1492 /* MAC filter - use one buffer for both lists */
1493 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1494 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1499 sg_init_table(sg, 2);
1501 /* Store the unicast list and count in the front of the buffer */
1502 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1504 netdev_for_each_uc_addr(ha, dev)
1505 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1507 sg_set_buf(&sg[0], mac_data,
1508 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1510 /* multicast list and count fill the end */
1511 mac_data = (void *)&mac_data->macs[uc_count][0];
1513 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1515 netdev_for_each_mc_addr(ha, dev)
1516 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1518 sg_set_buf(&sg[1], mac_data,
1519 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1521 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1522 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1523 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1528 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1529 __be16 proto, u16 vid)
1531 struct virtnet_info *vi = netdev_priv(dev);
1532 struct scatterlist sg;
1535 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1537 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1538 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1539 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1543 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1544 __be16 proto, u16 vid)
1546 struct virtnet_info *vi = netdev_priv(dev);
1547 struct scatterlist sg;
1550 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1552 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1553 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1554 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1558 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1562 if (vi->affinity_hint_set) {
1563 for (i = 0; i < vi->max_queue_pairs; i++) {
1564 virtqueue_set_affinity(vi->rq[i].vq, -1);
1565 virtqueue_set_affinity(vi->sq[i].vq, -1);
1568 vi->affinity_hint_set = false;
1572 static void virtnet_set_affinity(struct virtnet_info *vi)
1577 /* In multiqueue mode, when the number of cpu is equal to the number of
1578 * queue pairs, we let the queue pairs to be private to one cpu by
1579 * setting the affinity hint to eliminate the contention.
1581 if (vi->curr_queue_pairs == 1 ||
1582 vi->max_queue_pairs != num_online_cpus()) {
1583 virtnet_clean_affinity(vi, -1);
1588 for_each_online_cpu(cpu) {
1589 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1590 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1591 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1595 vi->affinity_hint_set = true;
1598 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1600 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1602 virtnet_set_affinity(vi);
1606 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1608 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1610 virtnet_set_affinity(vi);
1614 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
1616 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1619 virtnet_clean_affinity(vi, cpu);
1623 static enum cpuhp_state virtionet_online;
1625 static int virtnet_cpu_notif_add(struct virtnet_info *vi)
1629 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
1632 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1636 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1640 static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
1642 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1643 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1647 static void virtnet_get_ringparam(struct net_device *dev,
1648 struct ethtool_ringparam *ring)
1650 struct virtnet_info *vi = netdev_priv(dev);
1652 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1653 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1654 ring->rx_pending = ring->rx_max_pending;
1655 ring->tx_pending = ring->tx_max_pending;
1659 static void virtnet_get_drvinfo(struct net_device *dev,
1660 struct ethtool_drvinfo *info)
1662 struct virtnet_info *vi = netdev_priv(dev);
1663 struct virtio_device *vdev = vi->vdev;
1665 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1666 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1667 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1671 /* TODO: Eliminate OOO packets during switching */
1672 static int virtnet_set_channels(struct net_device *dev,
1673 struct ethtool_channels *channels)
1675 struct virtnet_info *vi = netdev_priv(dev);
1676 u16 queue_pairs = channels->combined_count;
1679 /* We don't support separate rx/tx channels.
1680 * We don't allow setting 'other' channels.
1682 if (channels->rx_count || channels->tx_count || channels->other_count)
1685 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
1688 /* For now we don't support modifying channels while XDP is loaded
1689 * also when XDP is loaded all RX queues have XDP programs so we only
1690 * need to check a single RX queue.
1692 if (vi->rq[0].xdp_prog)
1696 err = _virtnet_set_queues(vi, queue_pairs);
1698 netif_set_real_num_tx_queues(dev, queue_pairs);
1699 netif_set_real_num_rx_queues(dev, queue_pairs);
1701 virtnet_set_affinity(vi);
1708 static void virtnet_get_channels(struct net_device *dev,
1709 struct ethtool_channels *channels)
1711 struct virtnet_info *vi = netdev_priv(dev);
1713 channels->combined_count = vi->curr_queue_pairs;
1714 channels->max_combined = vi->max_queue_pairs;
1715 channels->max_other = 0;
1716 channels->rx_count = 0;
1717 channels->tx_count = 0;
1718 channels->other_count = 0;
1721 /* Check if the user is trying to change anything besides speed/duplex */
1723 virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings *cmd)
1725 struct ethtool_link_ksettings diff1 = *cmd;
1726 struct ethtool_link_ksettings diff2 = {};
1728 /* cmd is always set so we need to clear it, validate the port type
1729 * and also without autonegotiation we can ignore advertising
1731 diff1.base.speed = 0;
1732 diff2.base.port = PORT_OTHER;
1733 ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
1734 diff1.base.duplex = 0;
1736 diff1.base.link_mode_masks_nwords = 0;
1738 return !memcmp(&diff1.base, &diff2.base, sizeof(diff1.base)) &&
1739 bitmap_empty(diff1.link_modes.supported,
1740 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
1741 bitmap_empty(diff1.link_modes.advertising,
1742 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
1743 bitmap_empty(diff1.link_modes.lp_advertising,
1744 __ETHTOOL_LINK_MODE_MASK_NBITS);
1747 static int virtnet_set_link_ksettings(struct net_device *dev,
1748 const struct ethtool_link_ksettings *cmd)
1750 struct virtnet_info *vi = netdev_priv(dev);
1753 speed = cmd->base.speed;
1754 /* don't allow custom speed and duplex */
1755 if (!ethtool_validate_speed(speed) ||
1756 !ethtool_validate_duplex(cmd->base.duplex) ||
1757 !virtnet_validate_ethtool_cmd(cmd))
1760 vi->duplex = cmd->base.duplex;
1765 static int virtnet_get_link_ksettings(struct net_device *dev,
1766 struct ethtool_link_ksettings *cmd)
1768 struct virtnet_info *vi = netdev_priv(dev);
1770 cmd->base.speed = vi->speed;
1771 cmd->base.duplex = vi->duplex;
1772 cmd->base.port = PORT_OTHER;
1777 static void virtnet_init_settings(struct net_device *dev)
1779 struct virtnet_info *vi = netdev_priv(dev);
1781 vi->speed = SPEED_UNKNOWN;
1782 vi->duplex = DUPLEX_UNKNOWN;
1785 static const struct ethtool_ops virtnet_ethtool_ops = {
1786 .get_drvinfo = virtnet_get_drvinfo,
1787 .get_link = ethtool_op_get_link,
1788 .get_ringparam = virtnet_get_ringparam,
1789 .set_channels = virtnet_set_channels,
1790 .get_channels = virtnet_get_channels,
1791 .get_ts_info = ethtool_op_get_ts_info,
1792 .get_link_ksettings = virtnet_get_link_ksettings,
1793 .set_link_ksettings = virtnet_set_link_ksettings,
1796 static void virtnet_freeze_down(struct virtio_device *vdev)
1798 struct virtnet_info *vi = vdev->priv;
1801 /* Make sure no work handler is accessing the device */
1802 flush_work(&vi->config_work);
1804 netif_device_detach(vi->dev);
1805 netif_tx_disable(vi->dev);
1806 cancel_delayed_work_sync(&vi->refill);
1808 if (netif_running(vi->dev)) {
1809 for (i = 0; i < vi->max_queue_pairs; i++) {
1810 napi_disable(&vi->rq[i].napi);
1811 virtnet_napi_tx_disable(&vi->sq[i].napi);
1816 static int init_vqs(struct virtnet_info *vi);
1817 static void _remove_vq_common(struct virtnet_info *vi);
1819 static int virtnet_restore_up(struct virtio_device *vdev)
1821 struct virtnet_info *vi = vdev->priv;
1828 virtio_device_ready(vdev);
1830 if (netif_running(vi->dev)) {
1831 for (i = 0; i < vi->curr_queue_pairs; i++)
1832 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1833 schedule_delayed_work(&vi->refill, 0);
1835 for (i = 0; i < vi->max_queue_pairs; i++) {
1836 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1837 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
1842 netif_device_attach(vi->dev);
1846 static int virtnet_reset(struct virtnet_info *vi, int curr_qp, int xdp_qp)
1848 struct virtio_device *dev = vi->vdev;
1851 virtio_config_disable(dev);
1852 dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
1853 virtnet_freeze_down(dev);
1854 _remove_vq_common(vi);
1856 virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
1857 virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER);
1859 ret = virtio_finalize_features(dev);
1863 vi->xdp_queue_pairs = xdp_qp;
1864 ret = virtnet_restore_up(dev);
1867 ret = _virtnet_set_queues(vi, curr_qp);
1871 virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
1872 virtio_config_enable(dev);
1875 virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
1879 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
1880 struct netlink_ext_ack *extack)
1882 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
1883 struct virtnet_info *vi = netdev_priv(dev);
1884 struct bpf_prog *old_prog;
1885 u16 xdp_qp = 0, curr_qp;
1888 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1889 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1890 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
1891 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO)) {
1892 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing LRO, disable LRO first");
1896 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
1897 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
1901 if (dev->mtu > max_sz) {
1902 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
1903 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
1907 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
1909 xdp_qp = nr_cpu_ids;
1911 /* XDP requires extra queues for XDP_TX */
1912 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
1913 NL_SET_ERR_MSG_MOD(extack, "Too few free TX rings available");
1914 netdev_warn(dev, "request %i queues but max is %i\n",
1915 curr_qp + xdp_qp, vi->max_queue_pairs);
1920 prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
1922 return PTR_ERR(prog);
1925 /* Changing the headroom in buffers is a disruptive operation because
1926 * existing buffers must be flushed and reallocated. This will happen
1927 * when a xdp program is initially added or xdp is disabled by removing
1928 * the xdp program resulting in number of XDP queues changing.
1930 if (vi->xdp_queue_pairs != xdp_qp) {
1931 err = virtnet_reset(vi, curr_qp + xdp_qp, xdp_qp);
1933 dev_warn(&dev->dev, "XDP reset failure.\n");
1934 goto virtio_reset_err;
1938 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
1940 for (i = 0; i < vi->max_queue_pairs; i++) {
1941 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
1942 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
1944 bpf_prog_put(old_prog);
1950 /* On reset error do our best to unwind XDP changes inflight and return
1951 * error up to user space for resolution. The underlying reset hung on
1952 * us so not much we can do here.
1955 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
1959 static u32 virtnet_xdp_query(struct net_device *dev)
1961 struct virtnet_info *vi = netdev_priv(dev);
1962 const struct bpf_prog *xdp_prog;
1965 for (i = 0; i < vi->max_queue_pairs; i++) {
1966 xdp_prog = rtnl_dereference(vi->rq[i].xdp_prog);
1968 return xdp_prog->aux->id;
1973 static int virtnet_xdp(struct net_device *dev, struct netdev_xdp *xdp)
1975 switch (xdp->command) {
1976 case XDP_SETUP_PROG:
1977 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
1978 case XDP_QUERY_PROG:
1979 xdp->prog_id = virtnet_xdp_query(dev);
1980 xdp->prog_attached = !!xdp->prog_id;
1987 static const struct net_device_ops virtnet_netdev = {
1988 .ndo_open = virtnet_open,
1989 .ndo_stop = virtnet_close,
1990 .ndo_start_xmit = start_xmit,
1991 .ndo_validate_addr = eth_validate_addr,
1992 .ndo_set_mac_address = virtnet_set_mac_address,
1993 .ndo_set_rx_mode = virtnet_set_rx_mode,
1994 .ndo_get_stats64 = virtnet_stats,
1995 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
1996 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
1997 #ifdef CONFIG_NET_POLL_CONTROLLER
1998 .ndo_poll_controller = virtnet_netpoll,
2000 .ndo_xdp = virtnet_xdp,
2001 .ndo_features_check = passthru_features_check,
2004 static void virtnet_config_changed_work(struct work_struct *work)
2006 struct virtnet_info *vi =
2007 container_of(work, struct virtnet_info, config_work);
2010 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
2011 struct virtio_net_config, status, &v) < 0)
2014 if (v & VIRTIO_NET_S_ANNOUNCE) {
2015 netdev_notify_peers(vi->dev);
2016 virtnet_ack_link_announce(vi);
2019 /* Ignore unknown (future) status bits */
2020 v &= VIRTIO_NET_S_LINK_UP;
2022 if (vi->status == v)
2027 if (vi->status & VIRTIO_NET_S_LINK_UP) {
2028 netif_carrier_on(vi->dev);
2029 netif_tx_wake_all_queues(vi->dev);
2031 netif_carrier_off(vi->dev);
2032 netif_tx_stop_all_queues(vi->dev);
2036 static void virtnet_config_changed(struct virtio_device *vdev)
2038 struct virtnet_info *vi = vdev->priv;
2040 schedule_work(&vi->config_work);
2043 static void virtnet_free_queues(struct virtnet_info *vi)
2047 for (i = 0; i < vi->max_queue_pairs; i++) {
2048 napi_hash_del(&vi->rq[i].napi);
2049 netif_napi_del(&vi->rq[i].napi);
2050 netif_napi_del(&vi->sq[i].napi);
2053 /* We called napi_hash_del() before netif_napi_del(),
2054 * we need to respect an RCU grace period before freeing vi->rq
2062 static void _free_receive_bufs(struct virtnet_info *vi)
2064 struct bpf_prog *old_prog;
2067 for (i = 0; i < vi->max_queue_pairs; i++) {
2068 while (vi->rq[i].pages)
2069 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
2071 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2072 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
2074 bpf_prog_put(old_prog);
2078 static void free_receive_bufs(struct virtnet_info *vi)
2081 _free_receive_bufs(vi);
2085 static void free_receive_page_frags(struct virtnet_info *vi)
2088 for (i = 0; i < vi->max_queue_pairs; i++)
2089 if (vi->rq[i].alloc_frag.page)
2090 put_page(vi->rq[i].alloc_frag.page);
2093 static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
2095 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
2097 else if (q < vi->curr_queue_pairs)
2103 static void free_unused_bufs(struct virtnet_info *vi)
2108 for (i = 0; i < vi->max_queue_pairs; i++) {
2109 struct virtqueue *vq = vi->sq[i].vq;
2110 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2111 if (!is_xdp_raw_buffer_queue(vi, i))
2114 put_page(virt_to_head_page(buf));
2118 for (i = 0; i < vi->max_queue_pairs; i++) {
2119 struct virtqueue *vq = vi->rq[i].vq;
2121 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2122 if (vi->mergeable_rx_bufs) {
2123 put_page(virt_to_head_page(buf));
2124 } else if (vi->big_packets) {
2125 give_pages(&vi->rq[i], buf);
2127 put_page(virt_to_head_page(buf));
2133 static void virtnet_del_vqs(struct virtnet_info *vi)
2135 struct virtio_device *vdev = vi->vdev;
2137 virtnet_clean_affinity(vi, -1);
2139 vdev->config->del_vqs(vdev);
2141 virtnet_free_queues(vi);
2144 /* How large should a single buffer be so a queue full of these can fit at
2145 * least one full packet?
2146 * Logic below assumes the mergeable buffer header is used.
2148 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
2150 const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2151 unsigned int rq_size = virtqueue_get_vring_size(vq);
2152 unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
2153 unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
2154 unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
2156 return max(max(min_buf_len, hdr_len) - hdr_len,
2157 (unsigned int)GOOD_PACKET_LEN);
2160 static int virtnet_find_vqs(struct virtnet_info *vi)
2162 vq_callback_t **callbacks;
2163 struct virtqueue **vqs;
2169 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2170 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2171 * possible control vq.
2173 total_vqs = vi->max_queue_pairs * 2 +
2174 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
2176 /* Allocate space for find_vqs parameters */
2177 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
2180 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
2183 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
2186 if (vi->mergeable_rx_bufs) {
2187 ctx = kzalloc(total_vqs * sizeof(*ctx), GFP_KERNEL);
2194 /* Parameters for control virtqueue, if any */
2196 callbacks[total_vqs - 1] = NULL;
2197 names[total_vqs - 1] = "control";
2200 /* Allocate/initialize parameters for send/receive virtqueues */
2201 for (i = 0; i < vi->max_queue_pairs; i++) {
2202 callbacks[rxq2vq(i)] = skb_recv_done;
2203 callbacks[txq2vq(i)] = skb_xmit_done;
2204 sprintf(vi->rq[i].name, "input.%d", i);
2205 sprintf(vi->sq[i].name, "output.%d", i);
2206 names[rxq2vq(i)] = vi->rq[i].name;
2207 names[txq2vq(i)] = vi->sq[i].name;
2209 ctx[rxq2vq(i)] = true;
2212 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
2218 vi->cvq = vqs[total_vqs - 1];
2219 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
2220 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2223 for (i = 0; i < vi->max_queue_pairs; i++) {
2224 vi->rq[i].vq = vqs[rxq2vq(i)];
2225 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
2226 vi->sq[i].vq = vqs[txq2vq(i)];
2248 static int virtnet_alloc_queues(struct virtnet_info *vi)
2252 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
2255 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
2259 INIT_DELAYED_WORK(&vi->refill, refill_work);
2260 for (i = 0; i < vi->max_queue_pairs; i++) {
2261 vi->rq[i].pages = NULL;
2262 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2264 netif_tx_napi_add(vi->dev, &vi->sq[i].napi, virtnet_poll_tx,
2265 napi_tx ? napi_weight : 0);
2267 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2268 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2269 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2280 static int init_vqs(struct virtnet_info *vi)
2284 /* Allocate send & receive queues */
2285 ret = virtnet_alloc_queues(vi);
2289 ret = virtnet_find_vqs(vi);
2294 virtnet_set_affinity(vi);
2300 virtnet_free_queues(vi);
2306 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2307 struct rx_queue_attribute *attribute, char *buf)
2309 struct virtnet_info *vi = netdev_priv(queue->dev);
2310 unsigned int queue_index = get_netdev_rx_queue_index(queue);
2311 struct ewma_pkt_len *avg;
2313 BUG_ON(queue_index >= vi->max_queue_pairs);
2314 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2315 return sprintf(buf, "%u\n",
2316 get_mergeable_buf_len(&vi->rq[queue_index], avg));
2319 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2320 __ATTR_RO(mergeable_rx_buffer_size);
2322 static struct attribute *virtio_net_mrg_rx_attrs[] = {
2323 &mergeable_rx_buffer_size_attribute.attr,
2327 static const struct attribute_group virtio_net_mrg_rx_group = {
2328 .name = "virtio_net",
2329 .attrs = virtio_net_mrg_rx_attrs
2333 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2335 const char *fname, const char *dname)
2337 if (!virtio_has_feature(vdev, fbit))
2340 dev_err(&vdev->dev, "device advertises feature %s but not %s",
2346 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2347 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2349 static bool virtnet_validate_features(struct virtio_device *vdev)
2351 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2352 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2353 "VIRTIO_NET_F_CTRL_VQ") ||
2354 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2355 "VIRTIO_NET_F_CTRL_VQ") ||
2356 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2357 "VIRTIO_NET_F_CTRL_VQ") ||
2358 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2359 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2360 "VIRTIO_NET_F_CTRL_VQ"))) {
2367 #define MIN_MTU ETH_MIN_MTU
2368 #define MAX_MTU ETH_MAX_MTU
2370 static int virtnet_validate(struct virtio_device *vdev)
2372 if (!vdev->config->get) {
2373 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2378 if (!virtnet_validate_features(vdev))
2381 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2382 int mtu = virtio_cread16(vdev,
2383 offsetof(struct virtio_net_config,
2386 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2392 static int virtnet_probe(struct virtio_device *vdev)
2395 struct net_device *dev;
2396 struct virtnet_info *vi;
2397 u16 max_queue_pairs;
2400 /* Find if host supports multiqueue virtio_net device */
2401 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2402 struct virtio_net_config,
2403 max_virtqueue_pairs, &max_queue_pairs);
2405 /* We need at least 2 queue's */
2406 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
2407 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
2408 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2409 max_queue_pairs = 1;
2411 /* Allocate ourselves a network device with room for our info */
2412 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
2416 /* Set up network device as normal. */
2417 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
2418 dev->netdev_ops = &virtnet_netdev;
2419 dev->features = NETIF_F_HIGHDMA;
2421 dev->ethtool_ops = &virtnet_ethtool_ops;
2422 SET_NETDEV_DEV(dev, &vdev->dev);
2424 /* Do we support "hardware" checksums? */
2425 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
2426 /* This opens up the world of extra features. */
2427 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2429 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2431 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
2432 dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
2433 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
2435 /* Individual feature bits: what can host handle? */
2436 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
2437 dev->hw_features |= NETIF_F_TSO;
2438 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
2439 dev->hw_features |= NETIF_F_TSO6;
2440 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
2441 dev->hw_features |= NETIF_F_TSO_ECN;
2442 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
2443 dev->hw_features |= NETIF_F_UFO;
2445 dev->features |= NETIF_F_GSO_ROBUST;
2448 dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
2449 /* (!csum && gso) case will be fixed by register_netdev() */
2451 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
2452 dev->features |= NETIF_F_RXCSUM;
2454 dev->vlan_features = dev->features;
2456 /* MTU range: 68 - 65535 */
2457 dev->min_mtu = MIN_MTU;
2458 dev->max_mtu = MAX_MTU;
2460 /* Configuration may specify what MAC to use. Otherwise random. */
2461 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
2462 virtio_cread_bytes(vdev,
2463 offsetof(struct virtio_net_config, mac),
2464 dev->dev_addr, dev->addr_len);
2466 eth_hw_addr_random(dev);
2468 /* Set up our device-specific information */
2469 vi = netdev_priv(dev);
2473 vi->stats = alloc_percpu(struct virtnet_stats);
2475 if (vi->stats == NULL)
2478 for_each_possible_cpu(i) {
2479 struct virtnet_stats *virtnet_stats;
2480 virtnet_stats = per_cpu_ptr(vi->stats, i);
2481 u64_stats_init(&virtnet_stats->tx_syncp);
2482 u64_stats_init(&virtnet_stats->rx_syncp);
2485 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
2487 /* If we can receive ANY GSO packets, we must allocate large ones. */
2488 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2489 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2490 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
2491 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
2492 vi->big_packets = true;
2494 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
2495 vi->mergeable_rx_bufs = true;
2497 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
2498 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2499 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2501 vi->hdr_len = sizeof(struct virtio_net_hdr);
2503 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
2504 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2505 vi->any_header_sg = true;
2507 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2510 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2511 mtu = virtio_cread16(vdev,
2512 offsetof(struct virtio_net_config,
2514 if (mtu < dev->min_mtu) {
2515 /* Should never trigger: MTU was previously validated
2516 * in virtnet_validate.
2518 dev_err(&vdev->dev, "device MTU appears to have changed "
2519 "it is now %d < %d", mtu, dev->min_mtu);
2526 /* TODO: size buffers correctly in this case. */
2527 if (dev->mtu > ETH_DATA_LEN)
2528 vi->big_packets = true;
2531 if (vi->any_header_sg)
2532 dev->needed_headroom = vi->hdr_len;
2534 /* Enable multiqueue by default */
2535 if (num_online_cpus() >= max_queue_pairs)
2536 vi->curr_queue_pairs = max_queue_pairs;
2538 vi->curr_queue_pairs = num_online_cpus();
2539 vi->max_queue_pairs = max_queue_pairs;
2541 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
2547 if (vi->mergeable_rx_bufs)
2548 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
2550 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
2551 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
2553 virtnet_init_settings(dev);
2555 err = register_netdev(dev);
2557 pr_debug("virtio_net: registering device failed\n");
2561 virtio_device_ready(vdev);
2563 err = virtnet_cpu_notif_add(vi);
2565 pr_debug("virtio_net: registering cpu notifier failed\n");
2566 goto free_unregister_netdev;
2569 virtnet_set_queues(vi, vi->curr_queue_pairs);
2571 /* Assume link up if device can't report link status,
2572 otherwise get link status from config. */
2573 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
2574 netif_carrier_off(dev);
2575 schedule_work(&vi->config_work);
2577 vi->status = VIRTIO_NET_S_LINK_UP;
2578 netif_carrier_on(dev);
2581 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
2582 dev->name, max_queue_pairs);
2586 free_unregister_netdev:
2587 vi->vdev->config->reset(vdev);
2589 unregister_netdev(dev);
2591 cancel_delayed_work_sync(&vi->refill);
2592 free_receive_page_frags(vi);
2593 virtnet_del_vqs(vi);
2595 free_percpu(vi->stats);
2601 static void _remove_vq_common(struct virtnet_info *vi)
2603 vi->vdev->config->reset(vi->vdev);
2604 free_unused_bufs(vi);
2605 _free_receive_bufs(vi);
2606 free_receive_page_frags(vi);
2607 virtnet_del_vqs(vi);
2610 static void remove_vq_common(struct virtnet_info *vi)
2612 vi->vdev->config->reset(vi->vdev);
2614 /* Free unused buffers in both send and recv, if any. */
2615 free_unused_bufs(vi);
2617 free_receive_bufs(vi);
2619 free_receive_page_frags(vi);
2621 virtnet_del_vqs(vi);
2624 static void virtnet_remove(struct virtio_device *vdev)
2626 struct virtnet_info *vi = vdev->priv;
2628 virtnet_cpu_notif_remove(vi);
2630 /* Make sure no work handler is accessing the device. */
2631 flush_work(&vi->config_work);
2633 unregister_netdev(vi->dev);
2635 remove_vq_common(vi);
2637 free_percpu(vi->stats);
2638 free_netdev(vi->dev);
2641 #ifdef CONFIG_PM_SLEEP
2642 static int virtnet_freeze(struct virtio_device *vdev)
2644 struct virtnet_info *vi = vdev->priv;
2646 virtnet_cpu_notif_remove(vi);
2647 virtnet_freeze_down(vdev);
2648 remove_vq_common(vi);
2653 static int virtnet_restore(struct virtio_device *vdev)
2655 struct virtnet_info *vi = vdev->priv;
2658 err = virtnet_restore_up(vdev);
2661 virtnet_set_queues(vi, vi->curr_queue_pairs);
2663 err = virtnet_cpu_notif_add(vi);
2671 static struct virtio_device_id id_table[] = {
2672 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
2676 #define VIRTNET_FEATURES \
2677 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
2679 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
2680 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
2681 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
2682 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
2683 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
2684 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
2685 VIRTIO_NET_F_CTRL_MAC_ADDR, \
2688 static unsigned int features[] = {
2692 static unsigned int features_legacy[] = {
2695 VIRTIO_F_ANY_LAYOUT,
2698 static struct virtio_driver virtio_net_driver = {
2699 .feature_table = features,
2700 .feature_table_size = ARRAY_SIZE(features),
2701 .feature_table_legacy = features_legacy,
2702 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
2703 .driver.name = KBUILD_MODNAME,
2704 .driver.owner = THIS_MODULE,
2705 .id_table = id_table,
2706 .validate = virtnet_validate,
2707 .probe = virtnet_probe,
2708 .remove = virtnet_remove,
2709 .config_changed = virtnet_config_changed,
2710 #ifdef CONFIG_PM_SLEEP
2711 .freeze = virtnet_freeze,
2712 .restore = virtnet_restore,
2716 static __init int virtio_net_driver_init(void)
2720 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
2722 virtnet_cpu_down_prep);
2725 virtionet_online = ret;
2726 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
2727 NULL, virtnet_cpu_dead);
2731 ret = register_virtio_driver(&virtio_net_driver);
2736 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2738 cpuhp_remove_multi_state(virtionet_online);
2742 module_init(virtio_net_driver_init);
2744 static __exit void virtio_net_driver_exit(void)
2746 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2747 cpuhp_remove_multi_state(virtionet_online);
2748 unregister_virtio_driver(&virtio_net_driver);
2750 module_exit(virtio_net_driver_exit);
2752 MODULE_DEVICE_TABLE(virtio, id_table);
2753 MODULE_DESCRIPTION("Virtio network driver");
2754 MODULE_LICENSE("GPL");