1 /* A network driver using virtio.
3 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
19 #include <linux/netdevice.h>
20 #include <linux/etherdevice.h>
21 #include <linux/ethtool.h>
22 #include <linux/module.h>
23 #include <linux/virtio.h>
24 #include <linux/virtio_net.h>
25 #include <linux/bpf.h>
26 #include <linux/bpf_trace.h>
27 #include <linux/scatterlist.h>
28 #include <linux/if_vlan.h>
29 #include <linux/slab.h>
30 #include <linux/cpu.h>
31 #include <linux/average.h>
32 #include <linux/filter.h>
33 #include <net/route.h>
35 static int napi_weight = NAPI_POLL_WEIGHT;
36 module_param(napi_weight, int, 0444);
38 static bool csum = true, gso = true, napi_tx;
39 module_param(csum, bool, 0444);
40 module_param(gso, bool, 0444);
41 module_param(napi_tx, bool, 0644);
43 /* FIXME: MTU in config. */
44 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
45 #define GOOD_COPY_LEN 128
47 #define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
49 /* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
50 #define VIRTIO_XDP_HEADROOM 256
52 /* RX packet size EWMA. The average packet size is used to determine the packet
53 * buffer size when refilling RX rings. As the entire RX ring may be refilled
54 * at once, the weight is chosen so that the EWMA will be insensitive to short-
55 * term, transient changes in packet size.
57 DECLARE_EWMA(pkt_len, 0, 64)
59 #define VIRTNET_DRIVER_VERSION "1.0.0"
61 static const unsigned long guest_offloads[] = {
62 VIRTIO_NET_F_GUEST_TSO4,
63 VIRTIO_NET_F_GUEST_TSO6,
64 VIRTIO_NET_F_GUEST_ECN,
65 VIRTIO_NET_F_GUEST_UFO
68 struct virtnet_stats {
69 struct u64_stats_sync tx_syncp;
70 struct u64_stats_sync rx_syncp;
78 /* Internal representation of a send virtqueue */
80 /* Virtqueue associated with this send _queue */
83 /* TX: fragments + linear part + virtio header */
84 struct scatterlist sg[MAX_SKB_FRAGS + 2];
86 /* Name of the send queue: output.$index */
89 struct napi_struct napi;
92 /* Internal representation of a receive virtqueue */
93 struct receive_queue {
94 /* Virtqueue associated with this receive_queue */
97 struct napi_struct napi;
99 struct bpf_prog __rcu *xdp_prog;
101 /* Chain pages by the private ptr. */
104 /* Average packet length for mergeable receive buffers. */
105 struct ewma_pkt_len mrg_avg_pkt_len;
107 /* Page frag for packet buffer allocation. */
108 struct page_frag alloc_frag;
110 /* RX: fragments + linear part + virtio header */
111 struct scatterlist sg[MAX_SKB_FRAGS + 2];
113 /* Min single buffer size for mergeable buffers case. */
114 unsigned int min_buf_len;
116 /* Name of this receive queue: input.$index */
120 struct virtnet_info {
121 struct virtio_device *vdev;
122 struct virtqueue *cvq;
123 struct net_device *dev;
124 struct send_queue *sq;
125 struct receive_queue *rq;
128 /* Max # of queue pairs supported by the device */
131 /* # of queue pairs currently used by the driver */
132 u16 curr_queue_pairs;
134 /* # of XDP queue pairs currently used by the driver */
137 /* I like... big packets and I cannot lie! */
140 /* Host will merge rx buffers for big packets (shake it! shake it!) */
141 bool mergeable_rx_bufs;
143 /* Has control virtqueue */
146 /* Host can handle any s/g split between our header and packet data */
149 /* Packet virtio header size */
152 /* Active statistics */
153 struct virtnet_stats __percpu *stats;
155 /* Work struct for refilling if we run low on memory. */
156 struct delayed_work refill;
158 /* Work struct for config space updates */
159 struct work_struct config_work;
161 /* Does the affinity hint is set for virtqueues? */
162 bool affinity_hint_set;
164 /* CPU hotplug instances for online & dead */
165 struct hlist_node node;
166 struct hlist_node node_dead;
168 /* Control VQ buffers: protected by the rtnl lock */
169 struct virtio_net_ctrl_hdr ctrl_hdr;
170 virtio_net_ctrl_ack ctrl_status;
171 struct virtio_net_ctrl_mq ctrl_mq;
177 /* Ethtool settings */
181 unsigned long guest_offloads;
184 struct padded_vnet_hdr {
185 struct virtio_net_hdr_mrg_rxbuf hdr;
187 * hdr is in a separate sg buffer, and data sg buffer shares same page
188 * with this header sg. This padding makes next sg 16 byte aligned
194 /* Converting between virtqueue no. and kernel tx/rx queue no.
195 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
197 static int vq2txq(struct virtqueue *vq)
199 return (vq->index - 1) / 2;
202 static int txq2vq(int txq)
207 static int vq2rxq(struct virtqueue *vq)
209 return vq->index / 2;
212 static int rxq2vq(int rxq)
217 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
219 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
223 * private is used to chain pages for big packets, put the whole
224 * most recent used list in the beginning for reuse
226 static void give_pages(struct receive_queue *rq, struct page *page)
230 /* Find end of list, sew whole thing into vi->rq.pages. */
231 for (end = page; end->private; end = (struct page *)end->private);
232 end->private = (unsigned long)rq->pages;
236 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
238 struct page *p = rq->pages;
241 rq->pages = (struct page *)p->private;
242 /* clear private here, it is used to chain pages */
245 p = alloc_page(gfp_mask);
249 static void virtqueue_napi_schedule(struct napi_struct *napi,
250 struct virtqueue *vq)
252 if (napi_schedule_prep(napi)) {
253 virtqueue_disable_cb(vq);
254 __napi_schedule(napi);
258 static void virtqueue_napi_complete(struct napi_struct *napi,
259 struct virtqueue *vq, int processed)
263 opaque = virtqueue_enable_cb_prepare(vq);
264 if (napi_complete_done(napi, processed)) {
265 if (unlikely(virtqueue_poll(vq, opaque)))
266 virtqueue_napi_schedule(napi, vq);
268 virtqueue_disable_cb(vq);
272 static void skb_xmit_done(struct virtqueue *vq)
274 struct virtnet_info *vi = vq->vdev->priv;
275 struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
277 /* Suppress further interrupts. */
278 virtqueue_disable_cb(vq);
281 virtqueue_napi_schedule(napi, vq);
283 /* We were probably waiting for more output buffers. */
284 netif_wake_subqueue(vi->dev, vq2txq(vq));
287 #define MRG_CTX_HEADER_SHIFT 22
288 static void *mergeable_len_to_ctx(unsigned int truesize,
289 unsigned int headroom)
291 return (void *)(unsigned long)((headroom << MRG_CTX_HEADER_SHIFT) | truesize);
294 static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx)
296 return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT;
299 static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx)
301 return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1);
304 /* Called from bottom half context */
305 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
306 struct receive_queue *rq,
307 struct page *page, unsigned int offset,
308 unsigned int len, unsigned int truesize)
311 struct virtio_net_hdr_mrg_rxbuf *hdr;
312 unsigned int copy, hdr_len, hdr_padded_len;
315 p = page_address(page) + offset;
317 /* copy small packet so we can reuse these pages for small data */
318 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
322 hdr = skb_vnet_hdr(skb);
324 hdr_len = vi->hdr_len;
325 if (vi->mergeable_rx_bufs)
326 hdr_padded_len = sizeof(*hdr);
328 hdr_padded_len = sizeof(struct padded_vnet_hdr);
330 memcpy(hdr, p, hdr_len);
333 offset += hdr_padded_len;
337 if (copy > skb_tailroom(skb))
338 copy = skb_tailroom(skb);
339 skb_put_data(skb, p, copy);
344 if (vi->mergeable_rx_bufs) {
346 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
353 * Verify that we can indeed put this data into a skb.
354 * This is here to handle cases when the device erroneously
355 * tries to receive more than is possible. This is usually
356 * the case of a broken device.
358 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
359 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
363 BUG_ON(offset >= PAGE_SIZE);
365 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
366 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
367 frag_size, truesize);
369 page = (struct page *)page->private;
374 give_pages(rq, page);
379 static void virtnet_xdp_flush(struct net_device *dev)
381 struct virtnet_info *vi = netdev_priv(dev);
382 struct send_queue *sq;
385 qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
388 virtqueue_kick(sq->vq);
391 static bool __virtnet_xdp_xmit(struct virtnet_info *vi,
392 struct xdp_buff *xdp)
394 struct virtio_net_hdr_mrg_rxbuf *hdr;
396 struct send_queue *sq;
401 qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
404 /* Free up any pending old buffers before queueing new ones. */
405 while ((xdp_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) {
406 struct page *sent_page = virt_to_head_page(xdp_sent);
411 xdp->data -= vi->hdr_len;
412 /* Zero header and leave csum up to XDP layers */
414 memset(hdr, 0, vi->hdr_len);
416 sg_init_one(sq->sg, xdp->data, xdp->data_end - xdp->data);
418 err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp->data, GFP_ATOMIC);
420 struct page *page = virt_to_head_page(xdp->data);
429 static int virtnet_xdp_xmit(struct net_device *dev, struct xdp_buff *xdp)
431 struct virtnet_info *vi = netdev_priv(dev);
432 bool sent = __virtnet_xdp_xmit(vi, xdp);
439 static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
441 return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0;
444 /* We copy the packet for XDP in the following cases:
446 * 1) Packet is scattered across multiple rx buffers.
447 * 2) Headroom space is insufficient.
449 * This is inefficient but it's a temporary condition that
450 * we hit right after XDP is enabled and until queue is refilled
451 * with large buffers with sufficient headroom - so it should affect
452 * at most queue size packets.
453 * Afterwards, the conditions to enable
454 * XDP should preclude the underlying device from sending packets
455 * across multiple buffers (num_buf > 1), and we make sure buffers
456 * have enough headroom.
458 static struct page *xdp_linearize_page(struct receive_queue *rq,
465 struct page *page = alloc_page(GFP_ATOMIC);
470 memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
478 buf = virtqueue_get_buf(rq->vq, &buflen);
482 p = virt_to_head_page(buf);
483 off = buf - page_address(p);
485 /* guard against a misconfigured or uncooperative backend that
486 * is sending packet larger than the MTU.
488 if ((page_off + buflen) > PAGE_SIZE) {
493 memcpy(page_address(page) + page_off,
494 page_address(p) + off, buflen);
499 /* Headroom does not contribute to packet length */
500 *len = page_off - VIRTIO_XDP_HEADROOM;
503 __free_pages(page, 0);
507 static struct sk_buff *receive_small(struct net_device *dev,
508 struct virtnet_info *vi,
509 struct receive_queue *rq,
510 void *buf, void *ctx,
515 struct bpf_prog *xdp_prog;
516 unsigned int xdp_headroom = (unsigned long)ctx;
517 unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
518 unsigned int headroom = vi->hdr_len + header_offset;
519 unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
520 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
521 struct page *page = virt_to_head_page(buf);
522 unsigned int delta = 0, err;
523 struct page *xdp_page;
527 xdp_prog = rcu_dereference(rq->xdp_prog);
529 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
534 if (unlikely(hdr->hdr.gso_type || hdr->hdr.flags))
537 if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
538 int offset = buf - page_address(page) + header_offset;
539 unsigned int tlen = len + vi->hdr_len;
542 xdp_headroom = virtnet_get_headroom(vi);
543 header_offset = VIRTNET_RX_PAD + xdp_headroom;
544 headroom = vi->hdr_len + header_offset;
545 buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
546 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
547 xdp_page = xdp_linearize_page(rq, &num_buf, page,
548 offset, header_offset,
553 buf = page_address(xdp_page);
558 xdp.data_hard_start = buf + VIRTNET_RX_PAD + vi->hdr_len;
559 xdp.data = xdp.data_hard_start + xdp_headroom;
560 xdp_set_data_meta_invalid(&xdp);
561 xdp.data_end = xdp.data + len;
562 orig_data = xdp.data;
563 act = bpf_prog_run_xdp(xdp_prog, &xdp);
567 /* Recalculate length in case bpf program changed it */
568 delta = orig_data - xdp.data;
571 if (unlikely(!__virtnet_xdp_xmit(vi, &xdp)))
572 trace_xdp_exception(vi->dev, xdp_prog, act);
578 err = xdp_do_redirect(dev, &xdp, xdp_prog);
584 bpf_warn_invalid_xdp_action(act);
586 trace_xdp_exception(vi->dev, xdp_prog, act);
593 skb = build_skb(buf, buflen);
598 skb_reserve(skb, headroom - delta);
599 skb_put(skb, len + delta);
601 buf += header_offset;
602 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
603 } /* keep zeroed vnet hdr since packet was changed by bpf */
610 dev->stats.rx_dropped++;
616 static struct sk_buff *receive_big(struct net_device *dev,
617 struct virtnet_info *vi,
618 struct receive_queue *rq,
622 struct page *page = buf;
623 struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);
631 dev->stats.rx_dropped++;
632 give_pages(rq, page);
636 static struct sk_buff *receive_mergeable(struct net_device *dev,
637 struct virtnet_info *vi,
638 struct receive_queue *rq,
644 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
645 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
646 struct page *page = virt_to_head_page(buf);
647 int offset = buf - page_address(page);
648 struct sk_buff *head_skb, *curr_skb;
649 struct bpf_prog *xdp_prog;
650 unsigned int truesize;
651 unsigned int headroom = mergeable_ctx_to_headroom(ctx);
657 xdp_prog = rcu_dereference(rq->xdp_prog);
659 struct page *xdp_page;
664 /* This happens when rx buffer size is underestimated */
665 if (unlikely(num_buf > 1 ||
666 headroom < virtnet_get_headroom(vi))) {
667 /* linearize data for XDP */
668 xdp_page = xdp_linearize_page(rq, &num_buf,
674 offset = VIRTIO_XDP_HEADROOM;
679 /* Transient failure which in theory could occur if
680 * in-flight packets from before XDP was enabled reach
681 * the receive path after XDP is loaded. In practice I
682 * was not able to create this condition.
684 if (unlikely(hdr->hdr.gso_type))
687 /* Allow consuming headroom but reserve enough space to push
688 * the descriptor on if we get an XDP_TX return code.
690 data = page_address(xdp_page) + offset;
691 xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len;
692 xdp.data = data + vi->hdr_len;
693 xdp_set_data_meta_invalid(&xdp);
694 xdp.data_end = xdp.data + (len - vi->hdr_len);
695 act = bpf_prog_run_xdp(xdp_prog, &xdp);
698 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
702 /* recalculate offset to account for any header
703 * adjustments. Note other cases do not build an
704 * skb and avoid using offset
707 page_address(xdp_page) - vi->hdr_len;
709 /* We can only create skb based on xdp_page. */
710 if (unlikely(xdp_page != page)) {
713 head_skb = page_to_skb(vi, rq, xdp_page,
714 offset, len, PAGE_SIZE);
719 if (unlikely(!__virtnet_xdp_xmit(vi, &xdp)))
720 trace_xdp_exception(vi->dev, xdp_prog, act);
723 if (unlikely(xdp_page != page))
728 err = xdp_do_redirect(dev, &xdp, xdp_prog);
734 bpf_warn_invalid_xdp_action(act);
736 trace_xdp_exception(vi->dev, xdp_prog, act);
738 if (unlikely(xdp_page != page))
739 __free_pages(xdp_page, 0);
745 truesize = mergeable_ctx_to_truesize(ctx);
746 if (unlikely(len > truesize)) {
747 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
748 dev->name, len, (unsigned long)ctx);
749 dev->stats.rx_length_errors++;
753 head_skb = page_to_skb(vi, rq, page, offset, len, truesize);
756 if (unlikely(!curr_skb))
761 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
762 if (unlikely(!buf)) {
763 pr_debug("%s: rx error: %d buffers out of %d missing\n",
765 virtio16_to_cpu(vi->vdev,
767 dev->stats.rx_length_errors++;
771 page = virt_to_head_page(buf);
773 truesize = mergeable_ctx_to_truesize(ctx);
774 if (unlikely(len > truesize)) {
775 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
776 dev->name, len, (unsigned long)ctx);
777 dev->stats.rx_length_errors++;
781 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
782 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
783 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
787 if (curr_skb == head_skb)
788 skb_shinfo(curr_skb)->frag_list = nskb;
790 curr_skb->next = nskb;
792 head_skb->truesize += nskb->truesize;
795 if (curr_skb != head_skb) {
796 head_skb->data_len += len;
797 head_skb->len += len;
798 head_skb->truesize += truesize;
800 offset = buf - page_address(page);
801 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
803 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
806 skb_add_rx_frag(curr_skb, num_skb_frags, page,
807 offset, len, truesize);
811 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
819 buf = virtqueue_get_buf(rq->vq, &len);
820 if (unlikely(!buf)) {
821 pr_debug("%s: rx error: %d buffers missing\n",
823 dev->stats.rx_length_errors++;
826 page = virt_to_head_page(buf);
830 dev->stats.rx_dropped++;
831 dev_kfree_skb(head_skb);
836 static int receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
837 void *buf, unsigned int len, void **ctx, bool *xdp_xmit)
839 struct net_device *dev = vi->dev;
841 struct virtio_net_hdr_mrg_rxbuf *hdr;
844 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
845 pr_debug("%s: short packet %i\n", dev->name, len);
846 dev->stats.rx_length_errors++;
847 if (vi->mergeable_rx_bufs) {
848 put_page(virt_to_head_page(buf));
849 } else if (vi->big_packets) {
852 put_page(virt_to_head_page(buf));
857 if (vi->mergeable_rx_bufs)
858 skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit);
859 else if (vi->big_packets)
860 skb = receive_big(dev, vi, rq, buf, len);
862 skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit);
867 hdr = skb_vnet_hdr(skb);
871 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
872 skb->ip_summed = CHECKSUM_UNNECESSARY;
874 if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
875 virtio_is_little_endian(vi->vdev))) {
876 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
877 dev->name, hdr->hdr.gso_type,
882 skb->protocol = eth_type_trans(skb, dev);
883 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
884 ntohs(skb->protocol), skb->len, skb->pkt_type);
886 napi_gro_receive(&rq->napi, skb);
890 dev->stats.rx_frame_errors++;
895 /* Unlike mergeable buffers, all buffers are allocated to the
896 * same size, except for the headroom. For this reason we do
897 * not need to use mergeable_len_to_ctx here - it is enough
898 * to store the headroom as the context ignoring the truesize.
900 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
903 struct page_frag *alloc_frag = &rq->alloc_frag;
905 unsigned int xdp_headroom = virtnet_get_headroom(vi);
906 void *ctx = (void *)(unsigned long)xdp_headroom;
907 int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
910 len = SKB_DATA_ALIGN(len) +
911 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
912 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
915 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
916 get_page(alloc_frag->page);
917 alloc_frag->offset += len;
918 sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
919 vi->hdr_len + GOOD_PACKET_LEN);
920 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
922 put_page(virt_to_head_page(buf));
926 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
929 struct page *first, *list = NULL;
933 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
935 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
936 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
937 first = get_a_page(rq, gfp);
940 give_pages(rq, list);
943 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
945 /* chain new page in list head to match sg */
946 first->private = (unsigned long)list;
950 first = get_a_page(rq, gfp);
952 give_pages(rq, list);
955 p = page_address(first);
957 /* rq->sg[0], rq->sg[1] share the same page */
958 /* a separated rq->sg[0] for header - required in case !any_header_sg */
959 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
961 /* rq->sg[1] for data packet, from offset */
962 offset = sizeof(struct padded_vnet_hdr);
963 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
965 /* chain first in list head */
966 first->private = (unsigned long)list;
967 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
970 give_pages(rq, first);
975 static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
976 struct ewma_pkt_len *avg_pkt_len)
978 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
981 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
982 rq->min_buf_len, PAGE_SIZE - hdr_len);
983 return ALIGN(len, L1_CACHE_BYTES);
986 static int add_recvbuf_mergeable(struct virtnet_info *vi,
987 struct receive_queue *rq, gfp_t gfp)
989 struct page_frag *alloc_frag = &rq->alloc_frag;
990 unsigned int headroom = virtnet_get_headroom(vi);
994 unsigned int len, hole;
996 len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len);
997 if (unlikely(!skb_page_frag_refill(len + headroom, alloc_frag, gfp)))
1000 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1001 buf += headroom; /* advance address leaving hole at front of pkt */
1002 get_page(alloc_frag->page);
1003 alloc_frag->offset += len + headroom;
1004 hole = alloc_frag->size - alloc_frag->offset;
1005 if (hole < len + headroom) {
1006 /* To avoid internal fragmentation, if there is very likely not
1007 * enough space for another buffer, add the remaining space to
1008 * the current buffer.
1011 alloc_frag->offset += hole;
1014 sg_init_one(rq->sg, buf, len);
1015 ctx = mergeable_len_to_ctx(len, headroom);
1016 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1018 put_page(virt_to_head_page(buf));
1024 * Returns false if we couldn't fill entirely (OOM).
1026 * Normally run in the receive path, but can also be run from ndo_open
1027 * before we're receiving packets, or from refill_work which is
1028 * careful to disable receiving (using napi_disable).
1030 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
1037 if (vi->mergeable_rx_bufs)
1038 err = add_recvbuf_mergeable(vi, rq, gfp);
1039 else if (vi->big_packets)
1040 err = add_recvbuf_big(vi, rq, gfp);
1042 err = add_recvbuf_small(vi, rq, gfp);
1044 oom = err == -ENOMEM;
1047 } while (rq->vq->num_free);
1048 virtqueue_kick(rq->vq);
1052 static void skb_recv_done(struct virtqueue *rvq)
1054 struct virtnet_info *vi = rvq->vdev->priv;
1055 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
1057 virtqueue_napi_schedule(&rq->napi, rvq);
1060 static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
1064 /* If all buffers were filled by other side before we napi_enabled, we
1065 * won't get another interrupt, so process any outstanding packets now.
1066 * Call local_bh_enable after to trigger softIRQ processing.
1069 virtqueue_napi_schedule(napi, vq);
1073 static void virtnet_napi_tx_enable(struct virtnet_info *vi,
1074 struct virtqueue *vq,
1075 struct napi_struct *napi)
1080 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
1081 * enable the feature if this is likely affine with the transmit path.
1083 if (!vi->affinity_hint_set) {
1088 return virtnet_napi_enable(vq, napi);
1091 static void virtnet_napi_tx_disable(struct napi_struct *napi)
1097 static void refill_work(struct work_struct *work)
1099 struct virtnet_info *vi =
1100 container_of(work, struct virtnet_info, refill.work);
1104 for (i = 0; i < vi->curr_queue_pairs; i++) {
1105 struct receive_queue *rq = &vi->rq[i];
1107 napi_disable(&rq->napi);
1108 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
1109 virtnet_napi_enable(rq->vq, &rq->napi);
1111 /* In theory, this can happen: if we don't get any buffers in
1112 * we will *never* try to fill again.
1115 schedule_delayed_work(&vi->refill, HZ/2);
1119 static int virtnet_receive(struct receive_queue *rq, int budget, bool *xdp_xmit)
1121 struct virtnet_info *vi = rq->vq->vdev->priv;
1122 unsigned int len, received = 0, bytes = 0;
1124 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
1126 if (!vi->big_packets || vi->mergeable_rx_bufs) {
1129 while (received < budget &&
1130 (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) {
1131 bytes += receive_buf(vi, rq, buf, len, ctx, xdp_xmit);
1135 while (received < budget &&
1136 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
1137 bytes += receive_buf(vi, rq, buf, len, NULL, xdp_xmit);
1142 if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
1143 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
1144 schedule_delayed_work(&vi->refill, 0);
1147 u64_stats_update_begin(&stats->rx_syncp);
1148 stats->rx_bytes += bytes;
1149 stats->rx_packets += received;
1150 u64_stats_update_end(&stats->rx_syncp);
1155 static void free_old_xmit_skbs(struct send_queue *sq)
1157 struct sk_buff *skb;
1159 struct virtnet_info *vi = sq->vq->vdev->priv;
1160 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
1161 unsigned int packets = 0;
1162 unsigned int bytes = 0;
1164 while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1165 pr_debug("Sent skb %p\n", skb);
1170 dev_consume_skb_any(skb);
1173 /* Avoid overhead when no packets have been processed
1174 * happens when called speculatively from start_xmit.
1179 u64_stats_update_begin(&stats->tx_syncp);
1180 stats->tx_bytes += bytes;
1181 stats->tx_packets += packets;
1182 u64_stats_update_end(&stats->tx_syncp);
1185 static void virtnet_poll_cleantx(struct receive_queue *rq)
1187 struct virtnet_info *vi = rq->vq->vdev->priv;
1188 unsigned int index = vq2rxq(rq->vq);
1189 struct send_queue *sq = &vi->sq[index];
1190 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
1192 if (!sq->napi.weight)
1195 if (__netif_tx_trylock(txq)) {
1196 free_old_xmit_skbs(sq);
1197 __netif_tx_unlock(txq);
1200 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1201 netif_tx_wake_queue(txq);
1204 static int virtnet_poll(struct napi_struct *napi, int budget)
1206 struct receive_queue *rq =
1207 container_of(napi, struct receive_queue, napi);
1208 unsigned int received;
1209 bool xdp_xmit = false;
1211 virtnet_poll_cleantx(rq);
1213 received = virtnet_receive(rq, budget, &xdp_xmit);
1215 /* Out of packets? */
1216 if (received < budget)
1217 virtqueue_napi_complete(napi, rq->vq, received);
1225 static int virtnet_open(struct net_device *dev)
1227 struct virtnet_info *vi = netdev_priv(dev);
1230 for (i = 0; i < vi->max_queue_pairs; i++) {
1231 if (i < vi->curr_queue_pairs)
1232 /* Make sure we have some buffers: if oom use wq. */
1233 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1234 schedule_delayed_work(&vi->refill, 0);
1235 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1236 virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
1242 static int virtnet_poll_tx(struct napi_struct *napi, int budget)
1244 struct send_queue *sq = container_of(napi, struct send_queue, napi);
1245 struct virtnet_info *vi = sq->vq->vdev->priv;
1246 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, vq2txq(sq->vq));
1248 __netif_tx_lock(txq, raw_smp_processor_id());
1249 free_old_xmit_skbs(sq);
1250 __netif_tx_unlock(txq);
1252 virtqueue_napi_complete(napi, sq->vq, 0);
1254 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1255 netif_tx_wake_queue(txq);
1260 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1262 struct virtio_net_hdr_mrg_rxbuf *hdr;
1263 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1264 struct virtnet_info *vi = sq->vq->vdev->priv;
1266 unsigned hdr_len = vi->hdr_len;
1269 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1271 can_push = vi->any_header_sg &&
1272 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1273 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1274 /* Even if we can, don't push here yet as this would skew
1275 * csum_start offset below. */
1277 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1279 hdr = skb_vnet_hdr(skb);
1281 if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1282 virtio_is_little_endian(vi->vdev), false))
1285 if (vi->mergeable_rx_bufs)
1286 hdr->num_buffers = 0;
1288 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1290 __skb_push(skb, hdr_len);
1291 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1292 if (unlikely(num_sg < 0))
1294 /* Pull header back to avoid skew in tx bytes calculations. */
1295 __skb_pull(skb, hdr_len);
1297 sg_set_buf(sq->sg, hdr, hdr_len);
1298 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
1299 if (unlikely(num_sg < 0))
1303 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1306 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1308 struct virtnet_info *vi = netdev_priv(dev);
1309 int qnum = skb_get_queue_mapping(skb);
1310 struct send_queue *sq = &vi->sq[qnum];
1312 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1313 bool kick = !skb->xmit_more;
1314 bool use_napi = sq->napi.weight;
1316 /* Free up any pending old buffers before queueing new ones. */
1317 free_old_xmit_skbs(sq);
1319 if (use_napi && kick)
1320 virtqueue_enable_cb_delayed(sq->vq);
1322 /* timestamp packet in software */
1323 skb_tx_timestamp(skb);
1325 /* Try to transmit */
1326 err = xmit_skb(sq, skb);
1328 /* This should not happen! */
1329 if (unlikely(err)) {
1330 dev->stats.tx_fifo_errors++;
1331 if (net_ratelimit())
1333 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
1334 dev->stats.tx_dropped++;
1335 dev_kfree_skb_any(skb);
1336 return NETDEV_TX_OK;
1339 /* Don't wait up for transmitted skbs to be freed. */
1345 /* If running out of space, stop queue to avoid getting packets that we
1346 * are then unable to transmit.
1347 * An alternative would be to force queuing layer to requeue the skb by
1348 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1349 * returned in a normal path of operation: it means that driver is not
1350 * maintaining the TX queue stop/start state properly, and causes
1351 * the stack to do a non-trivial amount of useless work.
1352 * Since most packets only take 1 or 2 ring slots, stopping the queue
1353 * early means 16 slots are typically wasted.
1355 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1356 netif_stop_subqueue(dev, qnum);
1358 unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1359 /* More just got used, free them then recheck. */
1360 free_old_xmit_skbs(sq);
1361 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1362 netif_start_subqueue(dev, qnum);
1363 virtqueue_disable_cb(sq->vq);
1368 if (kick || netif_xmit_stopped(txq))
1369 virtqueue_kick(sq->vq);
1371 return NETDEV_TX_OK;
1375 * Send command via the control virtqueue and check status. Commands
1376 * supported by the hypervisor, as indicated by feature bits, should
1377 * never fail unless improperly formatted.
1379 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1380 struct scatterlist *out)
1382 struct scatterlist *sgs[4], hdr, stat;
1383 unsigned out_num = 0, tmp;
1385 /* Caller should know better */
1386 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1388 vi->ctrl_status = ~0;
1389 vi->ctrl_hdr.class = class;
1390 vi->ctrl_hdr.cmd = cmd;
1392 sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr));
1393 sgs[out_num++] = &hdr;
1396 sgs[out_num++] = out;
1398 /* Add return status. */
1399 sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status));
1400 sgs[out_num] = &stat;
1402 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1403 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1405 if (unlikely(!virtqueue_kick(vi->cvq)))
1406 return vi->ctrl_status == VIRTIO_NET_OK;
1408 /* Spin for a response, the kick causes an ioport write, trapping
1409 * into the hypervisor, so the request should be handled immediately.
1411 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1412 !virtqueue_is_broken(vi->cvq))
1415 return vi->ctrl_status == VIRTIO_NET_OK;
1418 static int virtnet_set_mac_address(struct net_device *dev, void *p)
1420 struct virtnet_info *vi = netdev_priv(dev);
1421 struct virtio_device *vdev = vi->vdev;
1423 struct sockaddr *addr;
1424 struct scatterlist sg;
1426 addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
1430 ret = eth_prepare_mac_addr_change(dev, addr);
1434 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1435 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1436 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1437 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1438 dev_warn(&vdev->dev,
1439 "Failed to set mac address by vq command.\n");
1443 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1444 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1447 /* Naturally, this has an atomicity problem. */
1448 for (i = 0; i < dev->addr_len; i++)
1449 virtio_cwrite8(vdev,
1450 offsetof(struct virtio_net_config, mac) +
1451 i, addr->sa_data[i]);
1454 eth_commit_mac_addr_change(dev, p);
1462 static void virtnet_stats(struct net_device *dev,
1463 struct rtnl_link_stats64 *tot)
1465 struct virtnet_info *vi = netdev_priv(dev);
1469 for_each_possible_cpu(cpu) {
1470 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
1471 u64 tpackets, tbytes, rpackets, rbytes;
1474 start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
1475 tpackets = stats->tx_packets;
1476 tbytes = stats->tx_bytes;
1477 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
1480 start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
1481 rpackets = stats->rx_packets;
1482 rbytes = stats->rx_bytes;
1483 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
1485 tot->rx_packets += rpackets;
1486 tot->tx_packets += tpackets;
1487 tot->rx_bytes += rbytes;
1488 tot->tx_bytes += tbytes;
1491 tot->tx_dropped = dev->stats.tx_dropped;
1492 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1493 tot->rx_dropped = dev->stats.rx_dropped;
1494 tot->rx_length_errors = dev->stats.rx_length_errors;
1495 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1498 #ifdef CONFIG_NET_POLL_CONTROLLER
1499 static void virtnet_netpoll(struct net_device *dev)
1501 struct virtnet_info *vi = netdev_priv(dev);
1504 for (i = 0; i < vi->curr_queue_pairs; i++)
1505 napi_schedule(&vi->rq[i].napi);
1509 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1512 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1513 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1514 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1518 static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1520 struct scatterlist sg;
1521 struct net_device *dev = vi->dev;
1523 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1526 vi->ctrl_mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1527 sg_init_one(&sg, &vi->ctrl_mq, sizeof(vi->ctrl_mq));
1529 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1530 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1531 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1535 vi->curr_queue_pairs = queue_pairs;
1536 /* virtnet_open() will refill when device is going to up. */
1537 if (dev->flags & IFF_UP)
1538 schedule_delayed_work(&vi->refill, 0);
1544 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1549 err = _virtnet_set_queues(vi, queue_pairs);
1554 static int virtnet_close(struct net_device *dev)
1556 struct virtnet_info *vi = netdev_priv(dev);
1559 /* Make sure refill_work doesn't re-enable napi! */
1560 cancel_delayed_work_sync(&vi->refill);
1562 for (i = 0; i < vi->max_queue_pairs; i++) {
1563 napi_disable(&vi->rq[i].napi);
1564 virtnet_napi_tx_disable(&vi->sq[i].napi);
1570 static void virtnet_set_rx_mode(struct net_device *dev)
1572 struct virtnet_info *vi = netdev_priv(dev);
1573 struct scatterlist sg[2];
1574 struct virtio_net_ctrl_mac *mac_data;
1575 struct netdev_hw_addr *ha;
1581 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1582 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1585 vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0);
1586 vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1588 sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc));
1590 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1591 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1592 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1593 vi->ctrl_promisc ? "en" : "dis");
1595 sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti));
1597 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1598 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1599 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1600 vi->ctrl_allmulti ? "en" : "dis");
1602 uc_count = netdev_uc_count(dev);
1603 mc_count = netdev_mc_count(dev);
1604 /* MAC filter - use one buffer for both lists */
1605 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1606 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1611 sg_init_table(sg, 2);
1613 /* Store the unicast list and count in the front of the buffer */
1614 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1616 netdev_for_each_uc_addr(ha, dev)
1617 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1619 sg_set_buf(&sg[0], mac_data,
1620 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1622 /* multicast list and count fill the end */
1623 mac_data = (void *)&mac_data->macs[uc_count][0];
1625 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1627 netdev_for_each_mc_addr(ha, dev)
1628 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1630 sg_set_buf(&sg[1], mac_data,
1631 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1633 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1634 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1635 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1640 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1641 __be16 proto, u16 vid)
1643 struct virtnet_info *vi = netdev_priv(dev);
1644 struct scatterlist sg;
1647 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1649 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1650 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1651 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1655 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1656 __be16 proto, u16 vid)
1658 struct virtnet_info *vi = netdev_priv(dev);
1659 struct scatterlist sg;
1662 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1664 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1665 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1666 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1670 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1674 if (vi->affinity_hint_set) {
1675 for (i = 0; i < vi->max_queue_pairs; i++) {
1676 virtqueue_set_affinity(vi->rq[i].vq, -1);
1677 virtqueue_set_affinity(vi->sq[i].vq, -1);
1680 vi->affinity_hint_set = false;
1684 static void virtnet_set_affinity(struct virtnet_info *vi)
1689 /* In multiqueue mode, when the number of cpu is equal to the number of
1690 * queue pairs, we let the queue pairs to be private to one cpu by
1691 * setting the affinity hint to eliminate the contention.
1693 if (vi->curr_queue_pairs == 1 ||
1694 vi->max_queue_pairs != num_online_cpus()) {
1695 virtnet_clean_affinity(vi, -1);
1700 for_each_online_cpu(cpu) {
1701 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1702 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1703 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1707 vi->affinity_hint_set = true;
1710 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1712 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1714 virtnet_set_affinity(vi);
1718 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1720 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1722 virtnet_set_affinity(vi);
1726 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
1728 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1731 virtnet_clean_affinity(vi, cpu);
1735 static enum cpuhp_state virtionet_online;
1737 static int virtnet_cpu_notif_add(struct virtnet_info *vi)
1741 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
1744 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1748 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1752 static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
1754 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1755 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1759 static void virtnet_get_ringparam(struct net_device *dev,
1760 struct ethtool_ringparam *ring)
1762 struct virtnet_info *vi = netdev_priv(dev);
1764 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1765 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1766 ring->rx_pending = ring->rx_max_pending;
1767 ring->tx_pending = ring->tx_max_pending;
1771 static void virtnet_get_drvinfo(struct net_device *dev,
1772 struct ethtool_drvinfo *info)
1774 struct virtnet_info *vi = netdev_priv(dev);
1775 struct virtio_device *vdev = vi->vdev;
1777 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1778 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1779 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1783 /* TODO: Eliminate OOO packets during switching */
1784 static int virtnet_set_channels(struct net_device *dev,
1785 struct ethtool_channels *channels)
1787 struct virtnet_info *vi = netdev_priv(dev);
1788 u16 queue_pairs = channels->combined_count;
1791 /* We don't support separate rx/tx channels.
1792 * We don't allow setting 'other' channels.
1794 if (channels->rx_count || channels->tx_count || channels->other_count)
1797 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
1800 /* For now we don't support modifying channels while XDP is loaded
1801 * also when XDP is loaded all RX queues have XDP programs so we only
1802 * need to check a single RX queue.
1804 if (vi->rq[0].xdp_prog)
1808 err = _virtnet_set_queues(vi, queue_pairs);
1810 netif_set_real_num_tx_queues(dev, queue_pairs);
1811 netif_set_real_num_rx_queues(dev, queue_pairs);
1813 virtnet_set_affinity(vi);
1820 static void virtnet_get_channels(struct net_device *dev,
1821 struct ethtool_channels *channels)
1823 struct virtnet_info *vi = netdev_priv(dev);
1825 channels->combined_count = vi->curr_queue_pairs;
1826 channels->max_combined = vi->max_queue_pairs;
1827 channels->max_other = 0;
1828 channels->rx_count = 0;
1829 channels->tx_count = 0;
1830 channels->other_count = 0;
1833 /* Check if the user is trying to change anything besides speed/duplex */
1835 virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings *cmd)
1837 struct ethtool_link_ksettings diff1 = *cmd;
1838 struct ethtool_link_ksettings diff2 = {};
1840 /* cmd is always set so we need to clear it, validate the port type
1841 * and also without autonegotiation we can ignore advertising
1843 diff1.base.speed = 0;
1844 diff2.base.port = PORT_OTHER;
1845 ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
1846 diff1.base.duplex = 0;
1848 diff1.base.link_mode_masks_nwords = 0;
1850 return !memcmp(&diff1.base, &diff2.base, sizeof(diff1.base)) &&
1851 bitmap_empty(diff1.link_modes.supported,
1852 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
1853 bitmap_empty(diff1.link_modes.advertising,
1854 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
1855 bitmap_empty(diff1.link_modes.lp_advertising,
1856 __ETHTOOL_LINK_MODE_MASK_NBITS);
1859 static int virtnet_set_link_ksettings(struct net_device *dev,
1860 const struct ethtool_link_ksettings *cmd)
1862 struct virtnet_info *vi = netdev_priv(dev);
1865 speed = cmd->base.speed;
1866 /* don't allow custom speed and duplex */
1867 if (!ethtool_validate_speed(speed) ||
1868 !ethtool_validate_duplex(cmd->base.duplex) ||
1869 !virtnet_validate_ethtool_cmd(cmd))
1872 vi->duplex = cmd->base.duplex;
1877 static int virtnet_get_link_ksettings(struct net_device *dev,
1878 struct ethtool_link_ksettings *cmd)
1880 struct virtnet_info *vi = netdev_priv(dev);
1882 cmd->base.speed = vi->speed;
1883 cmd->base.duplex = vi->duplex;
1884 cmd->base.port = PORT_OTHER;
1889 static void virtnet_init_settings(struct net_device *dev)
1891 struct virtnet_info *vi = netdev_priv(dev);
1893 vi->speed = SPEED_UNKNOWN;
1894 vi->duplex = DUPLEX_UNKNOWN;
1897 static const struct ethtool_ops virtnet_ethtool_ops = {
1898 .get_drvinfo = virtnet_get_drvinfo,
1899 .get_link = ethtool_op_get_link,
1900 .get_ringparam = virtnet_get_ringparam,
1901 .set_channels = virtnet_set_channels,
1902 .get_channels = virtnet_get_channels,
1903 .get_ts_info = ethtool_op_get_ts_info,
1904 .get_link_ksettings = virtnet_get_link_ksettings,
1905 .set_link_ksettings = virtnet_set_link_ksettings,
1908 static void virtnet_freeze_down(struct virtio_device *vdev)
1910 struct virtnet_info *vi = vdev->priv;
1913 /* Make sure no work handler is accessing the device */
1914 flush_work(&vi->config_work);
1916 netif_device_detach(vi->dev);
1917 netif_tx_disable(vi->dev);
1918 cancel_delayed_work_sync(&vi->refill);
1920 if (netif_running(vi->dev)) {
1921 for (i = 0; i < vi->max_queue_pairs; i++) {
1922 napi_disable(&vi->rq[i].napi);
1923 virtnet_napi_tx_disable(&vi->sq[i].napi);
1928 static int init_vqs(struct virtnet_info *vi);
1930 static int virtnet_restore_up(struct virtio_device *vdev)
1932 struct virtnet_info *vi = vdev->priv;
1939 virtio_device_ready(vdev);
1941 if (netif_running(vi->dev)) {
1942 for (i = 0; i < vi->curr_queue_pairs; i++)
1943 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1944 schedule_delayed_work(&vi->refill, 0);
1946 for (i = 0; i < vi->max_queue_pairs; i++) {
1947 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1948 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
1953 netif_device_attach(vi->dev);
1957 static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
1959 struct scatterlist sg;
1960 vi->ctrl_offloads = cpu_to_virtio64(vi->vdev, offloads);
1962 sg_init_one(&sg, &vi->ctrl_offloads, sizeof(vi->ctrl_offloads));
1964 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
1965 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
1966 dev_warn(&vi->dev->dev, "Fail to set guest offload. \n");
1973 static int virtnet_clear_guest_offloads(struct virtnet_info *vi)
1977 if (!vi->guest_offloads)
1980 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))
1981 offloads = 1ULL << VIRTIO_NET_F_GUEST_CSUM;
1983 return virtnet_set_guest_offloads(vi, offloads);
1986 static int virtnet_restore_guest_offloads(struct virtnet_info *vi)
1988 u64 offloads = vi->guest_offloads;
1990 if (!vi->guest_offloads)
1992 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))
1993 offloads |= 1ULL << VIRTIO_NET_F_GUEST_CSUM;
1995 return virtnet_set_guest_offloads(vi, offloads);
1998 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
1999 struct netlink_ext_ack *extack)
2001 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
2002 struct virtnet_info *vi = netdev_priv(dev);
2003 struct bpf_prog *old_prog;
2004 u16 xdp_qp = 0, curr_qp;
2007 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)
2008 && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2009 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2010 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
2011 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO))) {
2012 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing LRO, disable LRO first");
2016 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
2017 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
2021 if (dev->mtu > max_sz) {
2022 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
2023 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
2027 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
2029 xdp_qp = nr_cpu_ids;
2031 /* XDP requires extra queues for XDP_TX */
2032 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
2033 NL_SET_ERR_MSG_MOD(extack, "Too few free TX rings available");
2034 netdev_warn(dev, "request %i queues but max is %i\n",
2035 curr_qp + xdp_qp, vi->max_queue_pairs);
2040 prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
2042 return PTR_ERR(prog);
2045 /* Make sure NAPI is not using any XDP TX queues for RX. */
2046 for (i = 0; i < vi->max_queue_pairs; i++)
2047 napi_disable(&vi->rq[i].napi);
2049 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
2050 err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
2053 vi->xdp_queue_pairs = xdp_qp;
2055 for (i = 0; i < vi->max_queue_pairs; i++) {
2056 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2057 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
2060 virtnet_clear_guest_offloads(vi);
2062 virtnet_restore_guest_offloads(vi);
2065 bpf_prog_put(old_prog);
2066 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2072 for (i = 0; i < vi->max_queue_pairs; i++)
2073 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2075 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
2079 static u32 virtnet_xdp_query(struct net_device *dev)
2081 struct virtnet_info *vi = netdev_priv(dev);
2082 const struct bpf_prog *xdp_prog;
2085 for (i = 0; i < vi->max_queue_pairs; i++) {
2086 xdp_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2088 return xdp_prog->aux->id;
2093 static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
2095 switch (xdp->command) {
2096 case XDP_SETUP_PROG:
2097 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
2098 case XDP_QUERY_PROG:
2099 xdp->prog_id = virtnet_xdp_query(dev);
2100 xdp->prog_attached = !!xdp->prog_id;
2107 static const struct net_device_ops virtnet_netdev = {
2108 .ndo_open = virtnet_open,
2109 .ndo_stop = virtnet_close,
2110 .ndo_start_xmit = start_xmit,
2111 .ndo_validate_addr = eth_validate_addr,
2112 .ndo_set_mac_address = virtnet_set_mac_address,
2113 .ndo_set_rx_mode = virtnet_set_rx_mode,
2114 .ndo_get_stats64 = virtnet_stats,
2115 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
2116 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
2117 #ifdef CONFIG_NET_POLL_CONTROLLER
2118 .ndo_poll_controller = virtnet_netpoll,
2120 .ndo_bpf = virtnet_xdp,
2121 .ndo_xdp_xmit = virtnet_xdp_xmit,
2122 .ndo_xdp_flush = virtnet_xdp_flush,
2123 .ndo_features_check = passthru_features_check,
2126 static void virtnet_config_changed_work(struct work_struct *work)
2128 struct virtnet_info *vi =
2129 container_of(work, struct virtnet_info, config_work);
2132 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
2133 struct virtio_net_config, status, &v) < 0)
2136 if (v & VIRTIO_NET_S_ANNOUNCE) {
2137 netdev_notify_peers(vi->dev);
2138 virtnet_ack_link_announce(vi);
2141 /* Ignore unknown (future) status bits */
2142 v &= VIRTIO_NET_S_LINK_UP;
2144 if (vi->status == v)
2149 if (vi->status & VIRTIO_NET_S_LINK_UP) {
2150 netif_carrier_on(vi->dev);
2151 netif_tx_wake_all_queues(vi->dev);
2153 netif_carrier_off(vi->dev);
2154 netif_tx_stop_all_queues(vi->dev);
2158 static void virtnet_config_changed(struct virtio_device *vdev)
2160 struct virtnet_info *vi = vdev->priv;
2162 schedule_work(&vi->config_work);
2165 static void virtnet_free_queues(struct virtnet_info *vi)
2169 for (i = 0; i < vi->max_queue_pairs; i++) {
2170 napi_hash_del(&vi->rq[i].napi);
2171 netif_napi_del(&vi->rq[i].napi);
2172 netif_napi_del(&vi->sq[i].napi);
2175 /* We called napi_hash_del() before netif_napi_del(),
2176 * we need to respect an RCU grace period before freeing vi->rq
2184 static void _free_receive_bufs(struct virtnet_info *vi)
2186 struct bpf_prog *old_prog;
2189 for (i = 0; i < vi->max_queue_pairs; i++) {
2190 while (vi->rq[i].pages)
2191 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
2193 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2194 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
2196 bpf_prog_put(old_prog);
2200 static void free_receive_bufs(struct virtnet_info *vi)
2203 _free_receive_bufs(vi);
2207 static void free_receive_page_frags(struct virtnet_info *vi)
2210 for (i = 0; i < vi->max_queue_pairs; i++)
2211 if (vi->rq[i].alloc_frag.page)
2212 put_page(vi->rq[i].alloc_frag.page);
2215 static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
2217 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
2219 else if (q < vi->curr_queue_pairs)
2225 static void free_unused_bufs(struct virtnet_info *vi)
2230 for (i = 0; i < vi->max_queue_pairs; i++) {
2231 struct virtqueue *vq = vi->sq[i].vq;
2232 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2233 if (!is_xdp_raw_buffer_queue(vi, i))
2236 put_page(virt_to_head_page(buf));
2240 for (i = 0; i < vi->max_queue_pairs; i++) {
2241 struct virtqueue *vq = vi->rq[i].vq;
2243 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2244 if (vi->mergeable_rx_bufs) {
2245 put_page(virt_to_head_page(buf));
2246 } else if (vi->big_packets) {
2247 give_pages(&vi->rq[i], buf);
2249 put_page(virt_to_head_page(buf));
2255 static void virtnet_del_vqs(struct virtnet_info *vi)
2257 struct virtio_device *vdev = vi->vdev;
2259 virtnet_clean_affinity(vi, -1);
2261 vdev->config->del_vqs(vdev);
2263 virtnet_free_queues(vi);
2266 /* How large should a single buffer be so a queue full of these can fit at
2267 * least one full packet?
2268 * Logic below assumes the mergeable buffer header is used.
2270 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
2272 const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2273 unsigned int rq_size = virtqueue_get_vring_size(vq);
2274 unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
2275 unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
2276 unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
2278 return max(max(min_buf_len, hdr_len) - hdr_len,
2279 (unsigned int)GOOD_PACKET_LEN);
2282 static int virtnet_find_vqs(struct virtnet_info *vi)
2284 vq_callback_t **callbacks;
2285 struct virtqueue **vqs;
2291 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2292 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2293 * possible control vq.
2295 total_vqs = vi->max_queue_pairs * 2 +
2296 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
2298 /* Allocate space for find_vqs parameters */
2299 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
2302 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
2305 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
2308 if (!vi->big_packets || vi->mergeable_rx_bufs) {
2309 ctx = kzalloc(total_vqs * sizeof(*ctx), GFP_KERNEL);
2316 /* Parameters for control virtqueue, if any */
2318 callbacks[total_vqs - 1] = NULL;
2319 names[total_vqs - 1] = "control";
2322 /* Allocate/initialize parameters for send/receive virtqueues */
2323 for (i = 0; i < vi->max_queue_pairs; i++) {
2324 callbacks[rxq2vq(i)] = skb_recv_done;
2325 callbacks[txq2vq(i)] = skb_xmit_done;
2326 sprintf(vi->rq[i].name, "input.%d", i);
2327 sprintf(vi->sq[i].name, "output.%d", i);
2328 names[rxq2vq(i)] = vi->rq[i].name;
2329 names[txq2vq(i)] = vi->sq[i].name;
2331 ctx[rxq2vq(i)] = true;
2334 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
2340 vi->cvq = vqs[total_vqs - 1];
2341 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
2342 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2345 for (i = 0; i < vi->max_queue_pairs; i++) {
2346 vi->rq[i].vq = vqs[rxq2vq(i)];
2347 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
2348 vi->sq[i].vq = vqs[txq2vq(i)];
2370 static int virtnet_alloc_queues(struct virtnet_info *vi)
2374 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
2377 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
2381 INIT_DELAYED_WORK(&vi->refill, refill_work);
2382 for (i = 0; i < vi->max_queue_pairs; i++) {
2383 vi->rq[i].pages = NULL;
2384 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2386 netif_tx_napi_add(vi->dev, &vi->sq[i].napi, virtnet_poll_tx,
2387 napi_tx ? napi_weight : 0);
2389 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2390 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2391 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2402 static int init_vqs(struct virtnet_info *vi)
2406 /* Allocate send & receive queues */
2407 ret = virtnet_alloc_queues(vi);
2411 ret = virtnet_find_vqs(vi);
2416 virtnet_set_affinity(vi);
2422 virtnet_free_queues(vi);
2428 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2431 struct virtnet_info *vi = netdev_priv(queue->dev);
2432 unsigned int queue_index = get_netdev_rx_queue_index(queue);
2433 struct ewma_pkt_len *avg;
2435 BUG_ON(queue_index >= vi->max_queue_pairs);
2436 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2437 return sprintf(buf, "%u\n",
2438 get_mergeable_buf_len(&vi->rq[queue_index], avg));
2441 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2442 __ATTR_RO(mergeable_rx_buffer_size);
2444 static struct attribute *virtio_net_mrg_rx_attrs[] = {
2445 &mergeable_rx_buffer_size_attribute.attr,
2449 static const struct attribute_group virtio_net_mrg_rx_group = {
2450 .name = "virtio_net",
2451 .attrs = virtio_net_mrg_rx_attrs
2455 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2457 const char *fname, const char *dname)
2459 if (!virtio_has_feature(vdev, fbit))
2462 dev_err(&vdev->dev, "device advertises feature %s but not %s",
2468 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2469 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2471 static bool virtnet_validate_features(struct virtio_device *vdev)
2473 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2474 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2475 "VIRTIO_NET_F_CTRL_VQ") ||
2476 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2477 "VIRTIO_NET_F_CTRL_VQ") ||
2478 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2479 "VIRTIO_NET_F_CTRL_VQ") ||
2480 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2481 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2482 "VIRTIO_NET_F_CTRL_VQ"))) {
2489 #define MIN_MTU ETH_MIN_MTU
2490 #define MAX_MTU ETH_MAX_MTU
2492 static int virtnet_validate(struct virtio_device *vdev)
2494 if (!vdev->config->get) {
2495 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2500 if (!virtnet_validate_features(vdev))
2503 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2504 int mtu = virtio_cread16(vdev,
2505 offsetof(struct virtio_net_config,
2508 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2514 static int virtnet_probe(struct virtio_device *vdev)
2517 struct net_device *dev;
2518 struct virtnet_info *vi;
2519 u16 max_queue_pairs;
2522 /* Find if host supports multiqueue virtio_net device */
2523 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2524 struct virtio_net_config,
2525 max_virtqueue_pairs, &max_queue_pairs);
2527 /* We need at least 2 queue's */
2528 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
2529 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
2530 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2531 max_queue_pairs = 1;
2533 /* Allocate ourselves a network device with room for our info */
2534 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
2538 /* Set up network device as normal. */
2539 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
2540 dev->netdev_ops = &virtnet_netdev;
2541 dev->features = NETIF_F_HIGHDMA;
2543 dev->ethtool_ops = &virtnet_ethtool_ops;
2544 SET_NETDEV_DEV(dev, &vdev->dev);
2546 /* Do we support "hardware" checksums? */
2547 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
2548 /* This opens up the world of extra features. */
2549 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2551 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2553 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
2554 dev->hw_features |= NETIF_F_TSO
2555 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
2557 /* Individual feature bits: what can host handle? */
2558 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
2559 dev->hw_features |= NETIF_F_TSO;
2560 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
2561 dev->hw_features |= NETIF_F_TSO6;
2562 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
2563 dev->hw_features |= NETIF_F_TSO_ECN;
2565 dev->features |= NETIF_F_GSO_ROBUST;
2568 dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
2569 /* (!csum && gso) case will be fixed by register_netdev() */
2571 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
2572 dev->features |= NETIF_F_RXCSUM;
2574 dev->vlan_features = dev->features;
2576 /* MTU range: 68 - 65535 */
2577 dev->min_mtu = MIN_MTU;
2578 dev->max_mtu = MAX_MTU;
2580 /* Configuration may specify what MAC to use. Otherwise random. */
2581 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
2582 virtio_cread_bytes(vdev,
2583 offsetof(struct virtio_net_config, mac),
2584 dev->dev_addr, dev->addr_len);
2586 eth_hw_addr_random(dev);
2588 /* Set up our device-specific information */
2589 vi = netdev_priv(dev);
2593 vi->stats = alloc_percpu(struct virtnet_stats);
2595 if (vi->stats == NULL)
2598 for_each_possible_cpu(i) {
2599 struct virtnet_stats *virtnet_stats;
2600 virtnet_stats = per_cpu_ptr(vi->stats, i);
2601 u64_stats_init(&virtnet_stats->tx_syncp);
2602 u64_stats_init(&virtnet_stats->rx_syncp);
2605 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
2607 /* If we can receive ANY GSO packets, we must allocate large ones. */
2608 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2609 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2610 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
2611 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
2612 vi->big_packets = true;
2614 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
2615 vi->mergeable_rx_bufs = true;
2617 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
2618 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2619 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2621 vi->hdr_len = sizeof(struct virtio_net_hdr);
2623 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
2624 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2625 vi->any_header_sg = true;
2627 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2630 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2631 mtu = virtio_cread16(vdev,
2632 offsetof(struct virtio_net_config,
2634 if (mtu < dev->min_mtu) {
2635 /* Should never trigger: MTU was previously validated
2636 * in virtnet_validate.
2638 dev_err(&vdev->dev, "device MTU appears to have changed "
2639 "it is now %d < %d", mtu, dev->min_mtu);
2646 /* TODO: size buffers correctly in this case. */
2647 if (dev->mtu > ETH_DATA_LEN)
2648 vi->big_packets = true;
2651 if (vi->any_header_sg)
2652 dev->needed_headroom = vi->hdr_len;
2654 /* Enable multiqueue by default */
2655 if (num_online_cpus() >= max_queue_pairs)
2656 vi->curr_queue_pairs = max_queue_pairs;
2658 vi->curr_queue_pairs = num_online_cpus();
2659 vi->max_queue_pairs = max_queue_pairs;
2661 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
2667 if (vi->mergeable_rx_bufs)
2668 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
2670 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
2671 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
2673 virtnet_init_settings(dev);
2675 err = register_netdev(dev);
2677 pr_debug("virtio_net: registering device failed\n");
2681 virtio_device_ready(vdev);
2683 err = virtnet_cpu_notif_add(vi);
2685 pr_debug("virtio_net: registering cpu notifier failed\n");
2686 goto free_unregister_netdev;
2689 virtnet_set_queues(vi, vi->curr_queue_pairs);
2691 /* Assume link up if device can't report link status,
2692 otherwise get link status from config. */
2693 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
2694 netif_carrier_off(dev);
2695 schedule_work(&vi->config_work);
2697 vi->status = VIRTIO_NET_S_LINK_UP;
2698 netif_carrier_on(dev);
2701 for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
2702 if (virtio_has_feature(vi->vdev, guest_offloads[i]))
2703 set_bit(guest_offloads[i], &vi->guest_offloads);
2705 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
2706 dev->name, max_queue_pairs);
2710 free_unregister_netdev:
2711 vi->vdev->config->reset(vdev);
2713 unregister_netdev(dev);
2715 cancel_delayed_work_sync(&vi->refill);
2716 free_receive_page_frags(vi);
2717 virtnet_del_vqs(vi);
2719 free_percpu(vi->stats);
2725 static void remove_vq_common(struct virtnet_info *vi)
2727 vi->vdev->config->reset(vi->vdev);
2729 /* Free unused buffers in both send and recv, if any. */
2730 free_unused_bufs(vi);
2732 free_receive_bufs(vi);
2734 free_receive_page_frags(vi);
2736 virtnet_del_vqs(vi);
2739 static void virtnet_remove(struct virtio_device *vdev)
2741 struct virtnet_info *vi = vdev->priv;
2743 virtnet_cpu_notif_remove(vi);
2745 /* Make sure no work handler is accessing the device. */
2746 flush_work(&vi->config_work);
2748 unregister_netdev(vi->dev);
2750 remove_vq_common(vi);
2752 free_percpu(vi->stats);
2753 free_netdev(vi->dev);
2756 static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
2758 struct virtnet_info *vi = vdev->priv;
2760 virtnet_cpu_notif_remove(vi);
2761 virtnet_freeze_down(vdev);
2762 remove_vq_common(vi);
2767 static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
2769 struct virtnet_info *vi = vdev->priv;
2772 err = virtnet_restore_up(vdev);
2775 virtnet_set_queues(vi, vi->curr_queue_pairs);
2777 err = virtnet_cpu_notif_add(vi);
2784 static struct virtio_device_id id_table[] = {
2785 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
2789 #define VIRTNET_FEATURES \
2790 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
2792 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
2793 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
2794 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
2795 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
2796 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
2797 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
2798 VIRTIO_NET_F_CTRL_MAC_ADDR, \
2799 VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS
2801 static unsigned int features[] = {
2805 static unsigned int features_legacy[] = {
2808 VIRTIO_F_ANY_LAYOUT,
2811 static struct virtio_driver virtio_net_driver = {
2812 .feature_table = features,
2813 .feature_table_size = ARRAY_SIZE(features),
2814 .feature_table_legacy = features_legacy,
2815 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
2816 .driver.name = KBUILD_MODNAME,
2817 .driver.owner = THIS_MODULE,
2818 .id_table = id_table,
2819 .validate = virtnet_validate,
2820 .probe = virtnet_probe,
2821 .remove = virtnet_remove,
2822 .config_changed = virtnet_config_changed,
2823 #ifdef CONFIG_PM_SLEEP
2824 .freeze = virtnet_freeze,
2825 .restore = virtnet_restore,
2829 static __init int virtio_net_driver_init(void)
2833 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
2835 virtnet_cpu_down_prep);
2838 virtionet_online = ret;
2839 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
2840 NULL, virtnet_cpu_dead);
2844 ret = register_virtio_driver(&virtio_net_driver);
2849 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2851 cpuhp_remove_multi_state(virtionet_online);
2855 module_init(virtio_net_driver_init);
2857 static __exit void virtio_net_driver_exit(void)
2859 unregister_virtio_driver(&virtio_net_driver);
2860 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2861 cpuhp_remove_multi_state(virtionet_online);
2863 module_exit(virtio_net_driver_exit);
2865 MODULE_DEVICE_TABLE(virtio, id_table);
2866 MODULE_DESCRIPTION("Virtio network driver");
2867 MODULE_LICENSE("GPL");