1 /* A network driver using virtio.
3 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
19 #include <linux/netdevice.h>
20 #include <linux/etherdevice.h>
21 #include <linux/ethtool.h>
22 #include <linux/module.h>
23 #include <linux/virtio.h>
24 #include <linux/virtio_net.h>
25 #include <linux/bpf.h>
26 #include <linux/bpf_trace.h>
27 #include <linux/scatterlist.h>
28 #include <linux/if_vlan.h>
29 #include <linux/slab.h>
30 #include <linux/cpu.h>
31 #include <linux/average.h>
32 #include <net/route.h>
34 static int napi_weight
= NAPI_POLL_WEIGHT
;
35 module_param(napi_weight
, int, 0444);
37 static bool csum
= true, gso
= true, napi_tx
;
38 module_param(csum
, bool, 0444);
39 module_param(gso
, bool, 0444);
40 module_param(napi_tx
, bool, 0644);
42 /* FIXME: MTU in config. */
43 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
44 #define GOOD_COPY_LEN 128
46 #define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
48 /* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
49 #define VIRTIO_XDP_HEADROOM 256
51 /* RX packet size EWMA. The average packet size is used to determine the packet
52 * buffer size when refilling RX rings. As the entire RX ring may be refilled
53 * at once, the weight is chosen so that the EWMA will be insensitive to short-
54 * term, transient changes in packet size.
56 DECLARE_EWMA(pkt_len
, 0, 64)
58 #define VIRTNET_DRIVER_VERSION "1.0.0"
60 struct virtnet_stats
{
61 struct u64_stats_sync tx_syncp
;
62 struct u64_stats_sync rx_syncp
;
70 /* Internal representation of a send virtqueue */
72 /* Virtqueue associated with this send _queue */
75 /* TX: fragments + linear part + virtio header */
76 struct scatterlist sg
[MAX_SKB_FRAGS
+ 2];
78 /* Name of the send queue: output.$index */
81 struct napi_struct napi
;
84 /* Internal representation of a receive virtqueue */
85 struct receive_queue
{
86 /* Virtqueue associated with this receive_queue */
89 struct napi_struct napi
;
91 struct bpf_prog __rcu
*xdp_prog
;
93 /* Chain pages by the private ptr. */
96 /* Average packet length for mergeable receive buffers. */
97 struct ewma_pkt_len mrg_avg_pkt_len
;
99 /* Page frag for packet buffer allocation. */
100 struct page_frag alloc_frag
;
102 /* RX: fragments + linear part + virtio header */
103 struct scatterlist sg
[MAX_SKB_FRAGS
+ 2];
105 /* Min single buffer size for mergeable buffers case. */
106 unsigned int min_buf_len
;
108 /* Name of this receive queue: input.$index */
112 struct virtnet_info
{
113 struct virtio_device
*vdev
;
114 struct virtqueue
*cvq
;
115 struct net_device
*dev
;
116 struct send_queue
*sq
;
117 struct receive_queue
*rq
;
120 /* Max # of queue pairs supported by the device */
123 /* # of queue pairs currently used by the driver */
124 u16 curr_queue_pairs
;
126 /* # of XDP queue pairs currently used by the driver */
129 /* I like... big packets and I cannot lie! */
132 /* Host will merge rx buffers for big packets (shake it! shake it!) */
133 bool mergeable_rx_bufs
;
135 /* Has control virtqueue */
138 /* Host can handle any s/g split between our header and packet data */
141 /* Packet virtio header size */
144 /* Active statistics */
145 struct virtnet_stats __percpu
*stats
;
147 /* Work struct for refilling if we run low on memory. */
148 struct delayed_work refill
;
150 /* Work struct for config space updates */
151 struct work_struct config_work
;
153 /* Does the affinity hint is set for virtqueues? */
154 bool affinity_hint_set
;
156 /* CPU hotplug instances for online & dead */
157 struct hlist_node node
;
158 struct hlist_node node_dead
;
160 /* Control VQ buffers: protected by the rtnl lock */
161 struct virtio_net_ctrl_hdr ctrl_hdr
;
162 virtio_net_ctrl_ack ctrl_status
;
163 struct virtio_net_ctrl_mq ctrl_mq
;
168 /* Ethtool settings */
173 struct padded_vnet_hdr
{
174 struct virtio_net_hdr_mrg_rxbuf hdr
;
176 * hdr is in a separate sg buffer, and data sg buffer shares same page
177 * with this header sg. This padding makes next sg 16 byte aligned
183 /* Converting between virtqueue no. and kernel tx/rx queue no.
184 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
186 static int vq2txq(struct virtqueue
*vq
)
188 return (vq
->index
- 1) / 2;
191 static int txq2vq(int txq
)
196 static int vq2rxq(struct virtqueue
*vq
)
198 return vq
->index
/ 2;
201 static int rxq2vq(int rxq
)
206 static inline struct virtio_net_hdr_mrg_rxbuf
*skb_vnet_hdr(struct sk_buff
*skb
)
208 return (struct virtio_net_hdr_mrg_rxbuf
*)skb
->cb
;
212 * private is used to chain pages for big packets, put the whole
213 * most recent used list in the beginning for reuse
215 static void give_pages(struct receive_queue
*rq
, struct page
*page
)
219 /* Find end of list, sew whole thing into vi->rq.pages. */
220 for (end
= page
; end
->private; end
= (struct page
*)end
->private);
221 end
->private = (unsigned long)rq
->pages
;
225 static struct page
*get_a_page(struct receive_queue
*rq
, gfp_t gfp_mask
)
227 struct page
*p
= rq
->pages
;
230 rq
->pages
= (struct page
*)p
->private;
231 /* clear private here, it is used to chain pages */
234 p
= alloc_page(gfp_mask
);
238 static void virtqueue_napi_schedule(struct napi_struct
*napi
,
239 struct virtqueue
*vq
)
241 if (napi_schedule_prep(napi
)) {
242 virtqueue_disable_cb(vq
);
243 __napi_schedule(napi
);
247 static void virtqueue_napi_complete(struct napi_struct
*napi
,
248 struct virtqueue
*vq
, int processed
)
252 opaque
= virtqueue_enable_cb_prepare(vq
);
253 if (napi_complete_done(napi
, processed
) &&
254 unlikely(virtqueue_poll(vq
, opaque
)))
255 virtqueue_napi_schedule(napi
, vq
);
258 static void skb_xmit_done(struct virtqueue
*vq
)
260 struct virtnet_info
*vi
= vq
->vdev
->priv
;
261 struct napi_struct
*napi
= &vi
->sq
[vq2txq(vq
)].napi
;
263 /* Suppress further interrupts. */
264 virtqueue_disable_cb(vq
);
267 virtqueue_napi_schedule(napi
, vq
);
269 /* We were probably waiting for more output buffers. */
270 netif_wake_subqueue(vi
->dev
, vq2txq(vq
));
273 /* Called from bottom half context */
274 static struct sk_buff
*page_to_skb(struct virtnet_info
*vi
,
275 struct receive_queue
*rq
,
276 struct page
*page
, unsigned int offset
,
277 unsigned int len
, unsigned int truesize
)
280 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
281 unsigned int copy
, hdr_len
, hdr_padded_len
;
284 p
= page_address(page
) + offset
;
286 /* copy small packet so we can reuse these pages for small data */
287 skb
= napi_alloc_skb(&rq
->napi
, GOOD_COPY_LEN
);
291 hdr
= skb_vnet_hdr(skb
);
293 hdr_len
= vi
->hdr_len
;
294 if (vi
->mergeable_rx_bufs
)
295 hdr_padded_len
= sizeof *hdr
;
297 hdr_padded_len
= sizeof(struct padded_vnet_hdr
);
299 memcpy(hdr
, p
, hdr_len
);
302 offset
+= hdr_padded_len
;
306 if (copy
> skb_tailroom(skb
))
307 copy
= skb_tailroom(skb
);
308 memcpy(skb_put(skb
, copy
), p
, copy
);
313 if (vi
->mergeable_rx_bufs
) {
315 skb_add_rx_frag(skb
, 0, page
, offset
, len
, truesize
);
322 * Verify that we can indeed put this data into a skb.
323 * This is here to handle cases when the device erroneously
324 * tries to receive more than is possible. This is usually
325 * the case of a broken device.
327 if (unlikely(len
> MAX_SKB_FRAGS
* PAGE_SIZE
)) {
328 net_dbg_ratelimited("%s: too much data\n", skb
->dev
->name
);
332 BUG_ON(offset
>= PAGE_SIZE
);
334 unsigned int frag_size
= min((unsigned)PAGE_SIZE
- offset
, len
);
335 skb_add_rx_frag(skb
, skb_shinfo(skb
)->nr_frags
, page
, offset
,
336 frag_size
, truesize
);
338 page
= (struct page
*)page
->private;
343 give_pages(rq
, page
);
348 static bool virtnet_xdp_xmit(struct virtnet_info
*vi
,
349 struct receive_queue
*rq
,
350 struct xdp_buff
*xdp
)
352 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
354 struct send_queue
*sq
;
359 qp
= vi
->curr_queue_pairs
- vi
->xdp_queue_pairs
+ smp_processor_id();
362 /* Free up any pending old buffers before queueing new ones. */
363 while ((xdp_sent
= virtqueue_get_buf(sq
->vq
, &len
)) != NULL
) {
364 struct page
*sent_page
= virt_to_head_page(xdp_sent
);
369 xdp
->data
-= vi
->hdr_len
;
370 /* Zero header and leave csum up to XDP layers */
372 memset(hdr
, 0, vi
->hdr_len
);
374 sg_init_one(sq
->sg
, xdp
->data
, xdp
->data_end
- xdp
->data
);
376 err
= virtqueue_add_outbuf(sq
->vq
, sq
->sg
, 1, xdp
->data
, GFP_ATOMIC
);
378 struct page
*page
= virt_to_head_page(xdp
->data
);
384 virtqueue_kick(sq
->vq
);
388 static unsigned int virtnet_get_headroom(struct virtnet_info
*vi
)
390 return vi
->xdp_queue_pairs
? VIRTIO_XDP_HEADROOM
: 0;
393 static struct sk_buff
*receive_small(struct net_device
*dev
,
394 struct virtnet_info
*vi
,
395 struct receive_queue
*rq
,
396 void *buf
, unsigned int len
)
399 struct bpf_prog
*xdp_prog
;
400 unsigned int xdp_headroom
= virtnet_get_headroom(vi
);
401 unsigned int header_offset
= VIRTNET_RX_PAD
+ xdp_headroom
;
402 unsigned int headroom
= vi
->hdr_len
+ header_offset
;
403 unsigned int buflen
= SKB_DATA_ALIGN(GOOD_PACKET_LEN
+ headroom
) +
404 SKB_DATA_ALIGN(sizeof(struct skb_shared_info
));
405 unsigned int delta
= 0;
409 xdp_prog
= rcu_dereference(rq
->xdp_prog
);
411 struct virtio_net_hdr_mrg_rxbuf
*hdr
= buf
+ header_offset
;
416 if (unlikely(hdr
->hdr
.gso_type
|| hdr
->hdr
.flags
))
419 xdp
.data_hard_start
= buf
+ VIRTNET_RX_PAD
+ vi
->hdr_len
;
420 xdp
.data
= xdp
.data_hard_start
+ xdp_headroom
;
421 xdp
.data_end
= xdp
.data
+ len
;
422 orig_data
= xdp
.data
;
423 act
= bpf_prog_run_xdp(xdp_prog
, &xdp
);
427 /* Recalculate length in case bpf program changed it */
428 delta
= orig_data
- xdp
.data
;
431 if (unlikely(!virtnet_xdp_xmit(vi
, rq
, &xdp
)))
432 trace_xdp_exception(vi
->dev
, xdp_prog
, act
);
436 bpf_warn_invalid_xdp_action(act
);
438 trace_xdp_exception(vi
->dev
, xdp_prog
, act
);
445 skb
= build_skb(buf
, buflen
);
447 put_page(virt_to_head_page(buf
));
450 skb_reserve(skb
, headroom
- delta
);
451 skb_put(skb
, len
+ delta
);
453 buf
+= header_offset
;
454 memcpy(skb_vnet_hdr(skb
), buf
, vi
->hdr_len
);
455 } /* keep zeroed vnet hdr since packet was changed by bpf */
462 dev
->stats
.rx_dropped
++;
463 put_page(virt_to_head_page(buf
));
468 static struct sk_buff
*receive_big(struct net_device
*dev
,
469 struct virtnet_info
*vi
,
470 struct receive_queue
*rq
,
474 struct page
*page
= buf
;
475 struct sk_buff
*skb
= page_to_skb(vi
, rq
, page
, 0, len
, PAGE_SIZE
);
483 dev
->stats
.rx_dropped
++;
484 give_pages(rq
, page
);
488 /* The conditions to enable XDP should preclude the underlying device from
489 * sending packets across multiple buffers (num_buf > 1). However per spec
490 * it does not appear to be illegal to do so but rather just against convention.
491 * So in order to avoid making a system unresponsive the packets are pushed
492 * into a page and the XDP program is run. This will be extremely slow and we
493 * push a warning to the user to fix this as soon as possible. Fixing this may
494 * require resolving the underlying hardware to determine why multiple buffers
495 * are being received or simply loading the XDP program in the ingress stack
496 * after the skb is built because there is no advantage to running it here
499 static struct page
*xdp_linearize_page(struct receive_queue
*rq
,
505 struct page
*page
= alloc_page(GFP_ATOMIC
);
506 unsigned int page_off
= VIRTIO_XDP_HEADROOM
;
511 memcpy(page_address(page
) + page_off
, page_address(p
) + offset
, *len
);
519 buf
= virtqueue_get_buf(rq
->vq
, &buflen
);
523 p
= virt_to_head_page(buf
);
524 off
= buf
- page_address(p
);
526 /* guard against a misconfigured or uncooperative backend that
527 * is sending packet larger than the MTU.
529 if ((page_off
+ buflen
) > PAGE_SIZE
) {
534 memcpy(page_address(page
) + page_off
,
535 page_address(p
) + off
, buflen
);
540 /* Headroom does not contribute to packet length */
541 *len
= page_off
- VIRTIO_XDP_HEADROOM
;
544 __free_pages(page
, 0);
548 static struct sk_buff
*receive_mergeable(struct net_device
*dev
,
549 struct virtnet_info
*vi
,
550 struct receive_queue
*rq
,
555 struct virtio_net_hdr_mrg_rxbuf
*hdr
= buf
;
556 u16 num_buf
= virtio16_to_cpu(vi
->vdev
, hdr
->num_buffers
);
557 struct page
*page
= virt_to_head_page(buf
);
558 int offset
= buf
- page_address(page
);
559 struct sk_buff
*head_skb
, *curr_skb
;
560 struct bpf_prog
*xdp_prog
;
561 unsigned int truesize
;
566 xdp_prog
= rcu_dereference(rq
->xdp_prog
);
568 struct page
*xdp_page
;
573 /* This happens when rx buffer size is underestimated */
574 if (unlikely(num_buf
> 1)) {
575 /* linearize data for XDP */
576 xdp_page
= xdp_linearize_page(rq
, &num_buf
,
580 offset
= VIRTIO_XDP_HEADROOM
;
585 /* Transient failure which in theory could occur if
586 * in-flight packets from before XDP was enabled reach
587 * the receive path after XDP is loaded. In practice I
588 * was not able to create this condition.
590 if (unlikely(hdr
->hdr
.gso_type
))
593 /* Allow consuming headroom but reserve enough space to push
594 * the descriptor on if we get an XDP_TX return code.
596 data
= page_address(xdp_page
) + offset
;
597 xdp
.data_hard_start
= data
- VIRTIO_XDP_HEADROOM
+ vi
->hdr_len
;
598 xdp
.data
= data
+ vi
->hdr_len
;
599 xdp
.data_end
= xdp
.data
+ (len
- vi
->hdr_len
);
600 act
= bpf_prog_run_xdp(xdp_prog
, &xdp
);
604 /* recalculate offset to account for any header
605 * adjustments. Note other cases do not build an
606 * skb and avoid using offset
609 page_address(xdp_page
) - vi
->hdr_len
;
611 /* We can only create skb based on xdp_page. */
612 if (unlikely(xdp_page
!= page
)) {
615 head_skb
= page_to_skb(vi
, rq
, xdp_page
,
616 offset
, len
, PAGE_SIZE
);
617 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, len
);
622 if (unlikely(!virtnet_xdp_xmit(vi
, rq
, &xdp
)))
623 trace_xdp_exception(vi
->dev
, xdp_prog
, act
);
624 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, len
);
625 if (unlikely(xdp_page
!= page
))
630 bpf_warn_invalid_xdp_action(act
);
632 trace_xdp_exception(vi
->dev
, xdp_prog
, act
);
634 if (unlikely(xdp_page
!= page
))
635 __free_pages(xdp_page
, 0);
636 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, len
);
642 if (unlikely(len
> (unsigned long)ctx
)) {
643 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
644 dev
->name
, len
, (unsigned long)ctx
);
645 dev
->stats
.rx_length_errors
++;
648 truesize
= (unsigned long)ctx
;
649 head_skb
= page_to_skb(vi
, rq
, page
, offset
, len
, truesize
);
652 if (unlikely(!curr_skb
))
657 buf
= virtqueue_get_buf_ctx(rq
->vq
, &len
, &ctx
);
658 if (unlikely(!ctx
)) {
659 pr_debug("%s: rx error: %d buffers out of %d missing\n",
661 virtio16_to_cpu(vi
->vdev
,
663 dev
->stats
.rx_length_errors
++;
667 page
= virt_to_head_page(buf
);
668 if (unlikely(len
> (unsigned long)ctx
)) {
669 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
670 dev
->name
, len
, (unsigned long)ctx
);
671 dev
->stats
.rx_length_errors
++;
674 truesize
= (unsigned long)ctx
;
676 num_skb_frags
= skb_shinfo(curr_skb
)->nr_frags
;
677 if (unlikely(num_skb_frags
== MAX_SKB_FRAGS
)) {
678 struct sk_buff
*nskb
= alloc_skb(0, GFP_ATOMIC
);
682 if (curr_skb
== head_skb
)
683 skb_shinfo(curr_skb
)->frag_list
= nskb
;
685 curr_skb
->next
= nskb
;
687 head_skb
->truesize
+= nskb
->truesize
;
690 if (curr_skb
!= head_skb
) {
691 head_skb
->data_len
+= len
;
692 head_skb
->len
+= len
;
693 head_skb
->truesize
+= truesize
;
695 offset
= buf
- page_address(page
);
696 if (skb_can_coalesce(curr_skb
, num_skb_frags
, page
, offset
)) {
698 skb_coalesce_rx_frag(curr_skb
, num_skb_frags
- 1,
701 skb_add_rx_frag(curr_skb
, num_skb_frags
, page
,
702 offset
, len
, truesize
);
706 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, head_skb
->len
);
714 buf
= virtqueue_get_buf(rq
->vq
, &len
);
715 if (unlikely(!buf
)) {
716 pr_debug("%s: rx error: %d buffers missing\n",
718 dev
->stats
.rx_length_errors
++;
721 page
= virt_to_head_page(buf
);
725 dev
->stats
.rx_dropped
++;
726 dev_kfree_skb(head_skb
);
731 static int receive_buf(struct virtnet_info
*vi
, struct receive_queue
*rq
,
732 void *buf
, unsigned int len
, void **ctx
)
734 struct net_device
*dev
= vi
->dev
;
736 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
739 if (unlikely(len
< vi
->hdr_len
+ ETH_HLEN
)) {
740 pr_debug("%s: short packet %i\n", dev
->name
, len
);
741 dev
->stats
.rx_length_errors
++;
742 if (vi
->mergeable_rx_bufs
) {
743 put_page(virt_to_head_page(buf
));
744 } else if (vi
->big_packets
) {
747 put_page(virt_to_head_page(buf
));
752 if (vi
->mergeable_rx_bufs
)
753 skb
= receive_mergeable(dev
, vi
, rq
, buf
, ctx
, len
);
754 else if (vi
->big_packets
)
755 skb
= receive_big(dev
, vi
, rq
, buf
, len
);
757 skb
= receive_small(dev
, vi
, rq
, buf
, len
);
762 hdr
= skb_vnet_hdr(skb
);
766 if (hdr
->hdr
.flags
& VIRTIO_NET_HDR_F_DATA_VALID
)
767 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
769 if (virtio_net_hdr_to_skb(skb
, &hdr
->hdr
,
770 virtio_is_little_endian(vi
->vdev
))) {
771 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
772 dev
->name
, hdr
->hdr
.gso_type
,
777 skb
->protocol
= eth_type_trans(skb
, dev
);
778 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
779 ntohs(skb
->protocol
), skb
->len
, skb
->pkt_type
);
781 napi_gro_receive(&rq
->napi
, skb
);
785 dev
->stats
.rx_frame_errors
++;
790 static int add_recvbuf_small(struct virtnet_info
*vi
, struct receive_queue
*rq
,
793 struct page_frag
*alloc_frag
= &rq
->alloc_frag
;
795 unsigned int xdp_headroom
= virtnet_get_headroom(vi
);
796 int len
= vi
->hdr_len
+ VIRTNET_RX_PAD
+ GOOD_PACKET_LEN
+ xdp_headroom
;
799 len
= SKB_DATA_ALIGN(len
) +
800 SKB_DATA_ALIGN(sizeof(struct skb_shared_info
));
801 if (unlikely(!skb_page_frag_refill(len
, alloc_frag
, gfp
)))
804 buf
= (char *)page_address(alloc_frag
->page
) + alloc_frag
->offset
;
805 get_page(alloc_frag
->page
);
806 alloc_frag
->offset
+= len
;
807 sg_init_one(rq
->sg
, buf
+ VIRTNET_RX_PAD
+ xdp_headroom
,
808 vi
->hdr_len
+ GOOD_PACKET_LEN
);
809 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, 1, buf
, gfp
);
811 put_page(virt_to_head_page(buf
));
816 static int add_recvbuf_big(struct virtnet_info
*vi
, struct receive_queue
*rq
,
819 struct page
*first
, *list
= NULL
;
823 sg_init_table(rq
->sg
, MAX_SKB_FRAGS
+ 2);
825 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
826 for (i
= MAX_SKB_FRAGS
+ 1; i
> 1; --i
) {
827 first
= get_a_page(rq
, gfp
);
830 give_pages(rq
, list
);
833 sg_set_buf(&rq
->sg
[i
], page_address(first
), PAGE_SIZE
);
835 /* chain new page in list head to match sg */
836 first
->private = (unsigned long)list
;
840 first
= get_a_page(rq
, gfp
);
842 give_pages(rq
, list
);
845 p
= page_address(first
);
847 /* rq->sg[0], rq->sg[1] share the same page */
848 /* a separated rq->sg[0] for header - required in case !any_header_sg */
849 sg_set_buf(&rq
->sg
[0], p
, vi
->hdr_len
);
851 /* rq->sg[1] for data packet, from offset */
852 offset
= sizeof(struct padded_vnet_hdr
);
853 sg_set_buf(&rq
->sg
[1], p
+ offset
, PAGE_SIZE
- offset
);
855 /* chain first in list head */
856 first
->private = (unsigned long)list
;
857 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, MAX_SKB_FRAGS
+ 2,
860 give_pages(rq
, first
);
865 static unsigned int get_mergeable_buf_len(struct receive_queue
*rq
,
866 struct ewma_pkt_len
*avg_pkt_len
)
868 const size_t hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
871 len
= hdr_len
+ clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len
),
872 rq
->min_buf_len
, PAGE_SIZE
- hdr_len
);
873 return ALIGN(len
, L1_CACHE_BYTES
);
876 static int add_recvbuf_mergeable(struct virtnet_info
*vi
,
877 struct receive_queue
*rq
, gfp_t gfp
)
879 struct page_frag
*alloc_frag
= &rq
->alloc_frag
;
880 unsigned int headroom
= virtnet_get_headroom(vi
);
884 unsigned int len
, hole
;
886 len
= get_mergeable_buf_len(rq
, &rq
->mrg_avg_pkt_len
);
887 if (unlikely(!skb_page_frag_refill(len
+ headroom
, alloc_frag
, gfp
)))
890 buf
= (char *)page_address(alloc_frag
->page
) + alloc_frag
->offset
;
891 buf
+= headroom
; /* advance address leaving hole at front of pkt */
892 ctx
= (void *)(unsigned long)len
;
893 get_page(alloc_frag
->page
);
894 alloc_frag
->offset
+= len
+ headroom
;
895 hole
= alloc_frag
->size
- alloc_frag
->offset
;
896 if (hole
< len
+ headroom
) {
897 /* To avoid internal fragmentation, if there is very likely not
898 * enough space for another buffer, add the remaining space to
899 * the current buffer. This extra space is not included in
900 * the truesize stored in ctx.
903 alloc_frag
->offset
+= hole
;
906 sg_init_one(rq
->sg
, buf
, len
);
907 err
= virtqueue_add_inbuf_ctx(rq
->vq
, rq
->sg
, 1, buf
, ctx
, gfp
);
909 put_page(virt_to_head_page(buf
));
915 * Returns false if we couldn't fill entirely (OOM).
917 * Normally run in the receive path, but can also be run from ndo_open
918 * before we're receiving packets, or from refill_work which is
919 * careful to disable receiving (using napi_disable).
921 static bool try_fill_recv(struct virtnet_info
*vi
, struct receive_queue
*rq
,
929 if (vi
->mergeable_rx_bufs
)
930 err
= add_recvbuf_mergeable(vi
, rq
, gfp
);
931 else if (vi
->big_packets
)
932 err
= add_recvbuf_big(vi
, rq
, gfp
);
934 err
= add_recvbuf_small(vi
, rq
, gfp
);
936 oom
= err
== -ENOMEM
;
939 } while (rq
->vq
->num_free
);
940 virtqueue_kick(rq
->vq
);
944 static void skb_recv_done(struct virtqueue
*rvq
)
946 struct virtnet_info
*vi
= rvq
->vdev
->priv
;
947 struct receive_queue
*rq
= &vi
->rq
[vq2rxq(rvq
)];
949 virtqueue_napi_schedule(&rq
->napi
, rvq
);
952 static void virtnet_napi_enable(struct virtqueue
*vq
, struct napi_struct
*napi
)
956 /* If all buffers were filled by other side before we napi_enabled, we
957 * won't get another interrupt, so process any outstanding packets now.
958 * Call local_bh_enable after to trigger softIRQ processing.
961 virtqueue_napi_schedule(napi
, vq
);
965 static void virtnet_napi_tx_enable(struct virtnet_info
*vi
,
966 struct virtqueue
*vq
,
967 struct napi_struct
*napi
)
972 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
973 * enable the feature if this is likely affine with the transmit path.
975 if (!vi
->affinity_hint_set
) {
980 return virtnet_napi_enable(vq
, napi
);
983 static void virtnet_napi_tx_disable(struct napi_struct
*napi
)
989 static void refill_work(struct work_struct
*work
)
991 struct virtnet_info
*vi
=
992 container_of(work
, struct virtnet_info
, refill
.work
);
996 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++) {
997 struct receive_queue
*rq
= &vi
->rq
[i
];
999 napi_disable(&rq
->napi
);
1000 still_empty
= !try_fill_recv(vi
, rq
, GFP_KERNEL
);
1001 virtnet_napi_enable(rq
->vq
, &rq
->napi
);
1003 /* In theory, this can happen: if we don't get any buffers in
1004 * we will *never* try to fill again.
1007 schedule_delayed_work(&vi
->refill
, HZ
/2);
1011 static int virtnet_receive(struct receive_queue
*rq
, int budget
)
1013 struct virtnet_info
*vi
= rq
->vq
->vdev
->priv
;
1014 unsigned int len
, received
= 0, bytes
= 0;
1016 struct virtnet_stats
*stats
= this_cpu_ptr(vi
->stats
);
1018 if (vi
->mergeable_rx_bufs
) {
1021 while (received
< budget
&&
1022 (buf
= virtqueue_get_buf_ctx(rq
->vq
, &len
, &ctx
))) {
1023 bytes
+= receive_buf(vi
, rq
, buf
, len
, ctx
);
1027 while (received
< budget
&&
1028 (buf
= virtqueue_get_buf(rq
->vq
, &len
)) != NULL
) {
1029 bytes
+= receive_buf(vi
, rq
, buf
, len
, NULL
);
1034 if (rq
->vq
->num_free
> virtqueue_get_vring_size(rq
->vq
) / 2) {
1035 if (!try_fill_recv(vi
, rq
, GFP_ATOMIC
))
1036 schedule_delayed_work(&vi
->refill
, 0);
1039 u64_stats_update_begin(&stats
->rx_syncp
);
1040 stats
->rx_bytes
+= bytes
;
1041 stats
->rx_packets
+= received
;
1042 u64_stats_update_end(&stats
->rx_syncp
);
1047 static void free_old_xmit_skbs(struct send_queue
*sq
)
1049 struct sk_buff
*skb
;
1051 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
1052 struct virtnet_stats
*stats
= this_cpu_ptr(vi
->stats
);
1053 unsigned int packets
= 0;
1054 unsigned int bytes
= 0;
1056 while ((skb
= virtqueue_get_buf(sq
->vq
, &len
)) != NULL
) {
1057 pr_debug("Sent skb %p\n", skb
);
1062 dev_kfree_skb_any(skb
);
1065 /* Avoid overhead when no packets have been processed
1066 * happens when called speculatively from start_xmit.
1071 u64_stats_update_begin(&stats
->tx_syncp
);
1072 stats
->tx_bytes
+= bytes
;
1073 stats
->tx_packets
+= packets
;
1074 u64_stats_update_end(&stats
->tx_syncp
);
1077 static void virtnet_poll_cleantx(struct receive_queue
*rq
)
1079 struct virtnet_info
*vi
= rq
->vq
->vdev
->priv
;
1080 unsigned int index
= vq2rxq(rq
->vq
);
1081 struct send_queue
*sq
= &vi
->sq
[index
];
1082 struct netdev_queue
*txq
= netdev_get_tx_queue(vi
->dev
, index
);
1084 if (!sq
->napi
.weight
)
1087 if (__netif_tx_trylock(txq
)) {
1088 free_old_xmit_skbs(sq
);
1089 __netif_tx_unlock(txq
);
1092 if (sq
->vq
->num_free
>= 2 + MAX_SKB_FRAGS
)
1093 netif_tx_wake_queue(txq
);
1096 static int virtnet_poll(struct napi_struct
*napi
, int budget
)
1098 struct receive_queue
*rq
=
1099 container_of(napi
, struct receive_queue
, napi
);
1100 unsigned int received
;
1102 virtnet_poll_cleantx(rq
);
1104 received
= virtnet_receive(rq
, budget
);
1106 /* Out of packets? */
1107 if (received
< budget
)
1108 virtqueue_napi_complete(napi
, rq
->vq
, received
);
1113 static int virtnet_open(struct net_device
*dev
)
1115 struct virtnet_info
*vi
= netdev_priv(dev
);
1118 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1119 if (i
< vi
->curr_queue_pairs
)
1120 /* Make sure we have some buffers: if oom use wq. */
1121 if (!try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
))
1122 schedule_delayed_work(&vi
->refill
, 0);
1123 virtnet_napi_enable(vi
->rq
[i
].vq
, &vi
->rq
[i
].napi
);
1124 virtnet_napi_tx_enable(vi
, vi
->sq
[i
].vq
, &vi
->sq
[i
].napi
);
1130 static int virtnet_poll_tx(struct napi_struct
*napi
, int budget
)
1132 struct send_queue
*sq
= container_of(napi
, struct send_queue
, napi
);
1133 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
1134 struct netdev_queue
*txq
= netdev_get_tx_queue(vi
->dev
, vq2txq(sq
->vq
));
1136 __netif_tx_lock(txq
, raw_smp_processor_id());
1137 free_old_xmit_skbs(sq
);
1138 __netif_tx_unlock(txq
);
1140 virtqueue_napi_complete(napi
, sq
->vq
, 0);
1142 if (sq
->vq
->num_free
>= 2 + MAX_SKB_FRAGS
)
1143 netif_tx_wake_queue(txq
);
1148 static int xmit_skb(struct send_queue
*sq
, struct sk_buff
*skb
)
1150 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
1151 const unsigned char *dest
= ((struct ethhdr
*)skb
->data
)->h_dest
;
1152 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
1154 unsigned hdr_len
= vi
->hdr_len
;
1157 pr_debug("%s: xmit %p %pM\n", vi
->dev
->name
, skb
, dest
);
1159 can_push
= vi
->any_header_sg
&&
1160 !((unsigned long)skb
->data
& (__alignof__(*hdr
) - 1)) &&
1161 !skb_header_cloned(skb
) && skb_headroom(skb
) >= hdr_len
;
1162 /* Even if we can, don't push here yet as this would skew
1163 * csum_start offset below. */
1165 hdr
= (struct virtio_net_hdr_mrg_rxbuf
*)(skb
->data
- hdr_len
);
1167 hdr
= skb_vnet_hdr(skb
);
1169 if (virtio_net_hdr_from_skb(skb
, &hdr
->hdr
,
1170 virtio_is_little_endian(vi
->vdev
), false))
1173 if (vi
->mergeable_rx_bufs
)
1174 hdr
->num_buffers
= 0;
1176 sg_init_table(sq
->sg
, skb_shinfo(skb
)->nr_frags
+ (can_push
? 1 : 2));
1178 __skb_push(skb
, hdr_len
);
1179 num_sg
= skb_to_sgvec(skb
, sq
->sg
, 0, skb
->len
);
1180 /* Pull header back to avoid skew in tx bytes calculations. */
1181 __skb_pull(skb
, hdr_len
);
1183 sg_set_buf(sq
->sg
, hdr
, hdr_len
);
1184 num_sg
= skb_to_sgvec(skb
, sq
->sg
+ 1, 0, skb
->len
) + 1;
1186 return virtqueue_add_outbuf(sq
->vq
, sq
->sg
, num_sg
, skb
, GFP_ATOMIC
);
1189 static netdev_tx_t
start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
1191 struct virtnet_info
*vi
= netdev_priv(dev
);
1192 int qnum
= skb_get_queue_mapping(skb
);
1193 struct send_queue
*sq
= &vi
->sq
[qnum
];
1195 struct netdev_queue
*txq
= netdev_get_tx_queue(dev
, qnum
);
1196 bool kick
= !skb
->xmit_more
;
1197 bool use_napi
= sq
->napi
.weight
;
1199 /* Free up any pending old buffers before queueing new ones. */
1200 free_old_xmit_skbs(sq
);
1202 if (use_napi
&& kick
)
1203 virtqueue_enable_cb_delayed(sq
->vq
);
1205 /* timestamp packet in software */
1206 skb_tx_timestamp(skb
);
1208 /* Try to transmit */
1209 err
= xmit_skb(sq
, skb
);
1211 /* This should not happen! */
1212 if (unlikely(err
)) {
1213 dev
->stats
.tx_fifo_errors
++;
1214 if (net_ratelimit())
1216 "Unexpected TXQ (%d) queue failure: %d\n", qnum
, err
);
1217 dev
->stats
.tx_dropped
++;
1218 dev_kfree_skb_any(skb
);
1219 return NETDEV_TX_OK
;
1222 /* Don't wait up for transmitted skbs to be freed. */
1228 /* If running out of space, stop queue to avoid getting packets that we
1229 * are then unable to transmit.
1230 * An alternative would be to force queuing layer to requeue the skb by
1231 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1232 * returned in a normal path of operation: it means that driver is not
1233 * maintaining the TX queue stop/start state properly, and causes
1234 * the stack to do a non-trivial amount of useless work.
1235 * Since most packets only take 1 or 2 ring slots, stopping the queue
1236 * early means 16 slots are typically wasted.
1238 if (sq
->vq
->num_free
< 2+MAX_SKB_FRAGS
) {
1239 netif_stop_subqueue(dev
, qnum
);
1241 unlikely(!virtqueue_enable_cb_delayed(sq
->vq
))) {
1242 /* More just got used, free them then recheck. */
1243 free_old_xmit_skbs(sq
);
1244 if (sq
->vq
->num_free
>= 2+MAX_SKB_FRAGS
) {
1245 netif_start_subqueue(dev
, qnum
);
1246 virtqueue_disable_cb(sq
->vq
);
1251 if (kick
|| netif_xmit_stopped(txq
))
1252 virtqueue_kick(sq
->vq
);
1254 return NETDEV_TX_OK
;
1258 * Send command via the control virtqueue and check status. Commands
1259 * supported by the hypervisor, as indicated by feature bits, should
1260 * never fail unless improperly formatted.
1262 static bool virtnet_send_command(struct virtnet_info
*vi
, u8
class, u8 cmd
,
1263 struct scatterlist
*out
)
1265 struct scatterlist
*sgs
[4], hdr
, stat
;
1266 unsigned out_num
= 0, tmp
;
1268 /* Caller should know better */
1269 BUG_ON(!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VQ
));
1271 vi
->ctrl_status
= ~0;
1272 vi
->ctrl_hdr
.class = class;
1273 vi
->ctrl_hdr
.cmd
= cmd
;
1275 sg_init_one(&hdr
, &vi
->ctrl_hdr
, sizeof(vi
->ctrl_hdr
));
1276 sgs
[out_num
++] = &hdr
;
1279 sgs
[out_num
++] = out
;
1281 /* Add return status. */
1282 sg_init_one(&stat
, &vi
->ctrl_status
, sizeof(vi
->ctrl_status
));
1283 sgs
[out_num
] = &stat
;
1285 BUG_ON(out_num
+ 1 > ARRAY_SIZE(sgs
));
1286 virtqueue_add_sgs(vi
->cvq
, sgs
, out_num
, 1, vi
, GFP_ATOMIC
);
1288 if (unlikely(!virtqueue_kick(vi
->cvq
)))
1289 return vi
->ctrl_status
== VIRTIO_NET_OK
;
1291 /* Spin for a response, the kick causes an ioport write, trapping
1292 * into the hypervisor, so the request should be handled immediately.
1294 while (!virtqueue_get_buf(vi
->cvq
, &tmp
) &&
1295 !virtqueue_is_broken(vi
->cvq
))
1298 return vi
->ctrl_status
== VIRTIO_NET_OK
;
1301 static int virtnet_set_mac_address(struct net_device
*dev
, void *p
)
1303 struct virtnet_info
*vi
= netdev_priv(dev
);
1304 struct virtio_device
*vdev
= vi
->vdev
;
1306 struct sockaddr
*addr
;
1307 struct scatterlist sg
;
1309 addr
= kmemdup(p
, sizeof(*addr
), GFP_KERNEL
);
1313 ret
= eth_prepare_mac_addr_change(dev
, addr
);
1317 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_MAC_ADDR
)) {
1318 sg_init_one(&sg
, addr
->sa_data
, dev
->addr_len
);
1319 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MAC
,
1320 VIRTIO_NET_CTRL_MAC_ADDR_SET
, &sg
)) {
1321 dev_warn(&vdev
->dev
,
1322 "Failed to set mac address by vq command.\n");
1326 } else if (virtio_has_feature(vdev
, VIRTIO_NET_F_MAC
) &&
1327 !virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
)) {
1330 /* Naturally, this has an atomicity problem. */
1331 for (i
= 0; i
< dev
->addr_len
; i
++)
1332 virtio_cwrite8(vdev
,
1333 offsetof(struct virtio_net_config
, mac
) +
1334 i
, addr
->sa_data
[i
]);
1337 eth_commit_mac_addr_change(dev
, p
);
1345 static void virtnet_stats(struct net_device
*dev
,
1346 struct rtnl_link_stats64
*tot
)
1348 struct virtnet_info
*vi
= netdev_priv(dev
);
1352 for_each_possible_cpu(cpu
) {
1353 struct virtnet_stats
*stats
= per_cpu_ptr(vi
->stats
, cpu
);
1354 u64 tpackets
, tbytes
, rpackets
, rbytes
;
1357 start
= u64_stats_fetch_begin_irq(&stats
->tx_syncp
);
1358 tpackets
= stats
->tx_packets
;
1359 tbytes
= stats
->tx_bytes
;
1360 } while (u64_stats_fetch_retry_irq(&stats
->tx_syncp
, start
));
1363 start
= u64_stats_fetch_begin_irq(&stats
->rx_syncp
);
1364 rpackets
= stats
->rx_packets
;
1365 rbytes
= stats
->rx_bytes
;
1366 } while (u64_stats_fetch_retry_irq(&stats
->rx_syncp
, start
));
1368 tot
->rx_packets
+= rpackets
;
1369 tot
->tx_packets
+= tpackets
;
1370 tot
->rx_bytes
+= rbytes
;
1371 tot
->tx_bytes
+= tbytes
;
1374 tot
->tx_dropped
= dev
->stats
.tx_dropped
;
1375 tot
->tx_fifo_errors
= dev
->stats
.tx_fifo_errors
;
1376 tot
->rx_dropped
= dev
->stats
.rx_dropped
;
1377 tot
->rx_length_errors
= dev
->stats
.rx_length_errors
;
1378 tot
->rx_frame_errors
= dev
->stats
.rx_frame_errors
;
1381 #ifdef CONFIG_NET_POLL_CONTROLLER
1382 static void virtnet_netpoll(struct net_device
*dev
)
1384 struct virtnet_info
*vi
= netdev_priv(dev
);
1387 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++)
1388 napi_schedule(&vi
->rq
[i
].napi
);
1392 static void virtnet_ack_link_announce(struct virtnet_info
*vi
)
1395 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_ANNOUNCE
,
1396 VIRTIO_NET_CTRL_ANNOUNCE_ACK
, NULL
))
1397 dev_warn(&vi
->dev
->dev
, "Failed to ack link announce.\n");
1401 static int _virtnet_set_queues(struct virtnet_info
*vi
, u16 queue_pairs
)
1403 struct scatterlist sg
;
1404 struct net_device
*dev
= vi
->dev
;
1406 if (!vi
->has_cvq
|| !virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_MQ
))
1409 vi
->ctrl_mq
.virtqueue_pairs
= cpu_to_virtio16(vi
->vdev
, queue_pairs
);
1410 sg_init_one(&sg
, &vi
->ctrl_mq
, sizeof(vi
->ctrl_mq
));
1412 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MQ
,
1413 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET
, &sg
)) {
1414 dev_warn(&dev
->dev
, "Fail to set num of queue pairs to %d\n",
1418 vi
->curr_queue_pairs
= queue_pairs
;
1419 /* virtnet_open() will refill when device is going to up. */
1420 if (dev
->flags
& IFF_UP
)
1421 schedule_delayed_work(&vi
->refill
, 0);
1427 static int virtnet_set_queues(struct virtnet_info
*vi
, u16 queue_pairs
)
1432 err
= _virtnet_set_queues(vi
, queue_pairs
);
1437 static int virtnet_close(struct net_device
*dev
)
1439 struct virtnet_info
*vi
= netdev_priv(dev
);
1442 /* Make sure refill_work doesn't re-enable napi! */
1443 cancel_delayed_work_sync(&vi
->refill
);
1445 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1446 napi_disable(&vi
->rq
[i
].napi
);
1447 virtnet_napi_tx_disable(&vi
->sq
[i
].napi
);
1453 static void virtnet_set_rx_mode(struct net_device
*dev
)
1455 struct virtnet_info
*vi
= netdev_priv(dev
);
1456 struct scatterlist sg
[2];
1457 struct virtio_net_ctrl_mac
*mac_data
;
1458 struct netdev_hw_addr
*ha
;
1464 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1465 if (!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_RX
))
1468 vi
->ctrl_promisc
= ((dev
->flags
& IFF_PROMISC
) != 0);
1469 vi
->ctrl_allmulti
= ((dev
->flags
& IFF_ALLMULTI
) != 0);
1471 sg_init_one(sg
, &vi
->ctrl_promisc
, sizeof(vi
->ctrl_promisc
));
1473 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_RX
,
1474 VIRTIO_NET_CTRL_RX_PROMISC
, sg
))
1475 dev_warn(&dev
->dev
, "Failed to %sable promisc mode.\n",
1476 vi
->ctrl_promisc
? "en" : "dis");
1478 sg_init_one(sg
, &vi
->ctrl_allmulti
, sizeof(vi
->ctrl_allmulti
));
1480 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_RX
,
1481 VIRTIO_NET_CTRL_RX_ALLMULTI
, sg
))
1482 dev_warn(&dev
->dev
, "Failed to %sable allmulti mode.\n",
1483 vi
->ctrl_allmulti
? "en" : "dis");
1485 uc_count
= netdev_uc_count(dev
);
1486 mc_count
= netdev_mc_count(dev
);
1487 /* MAC filter - use one buffer for both lists */
1488 buf
= kzalloc(((uc_count
+ mc_count
) * ETH_ALEN
) +
1489 (2 * sizeof(mac_data
->entries
)), GFP_ATOMIC
);
1494 sg_init_table(sg
, 2);
1496 /* Store the unicast list and count in the front of the buffer */
1497 mac_data
->entries
= cpu_to_virtio32(vi
->vdev
, uc_count
);
1499 netdev_for_each_uc_addr(ha
, dev
)
1500 memcpy(&mac_data
->macs
[i
++][0], ha
->addr
, ETH_ALEN
);
1502 sg_set_buf(&sg
[0], mac_data
,
1503 sizeof(mac_data
->entries
) + (uc_count
* ETH_ALEN
));
1505 /* multicast list and count fill the end */
1506 mac_data
= (void *)&mac_data
->macs
[uc_count
][0];
1508 mac_data
->entries
= cpu_to_virtio32(vi
->vdev
, mc_count
);
1510 netdev_for_each_mc_addr(ha
, dev
)
1511 memcpy(&mac_data
->macs
[i
++][0], ha
->addr
, ETH_ALEN
);
1513 sg_set_buf(&sg
[1], mac_data
,
1514 sizeof(mac_data
->entries
) + (mc_count
* ETH_ALEN
));
1516 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MAC
,
1517 VIRTIO_NET_CTRL_MAC_TABLE_SET
, sg
))
1518 dev_warn(&dev
->dev
, "Failed to set MAC filter table.\n");
1523 static int virtnet_vlan_rx_add_vid(struct net_device
*dev
,
1524 __be16 proto
, u16 vid
)
1526 struct virtnet_info
*vi
= netdev_priv(dev
);
1527 struct scatterlist sg
;
1530 sg_init_one(&sg
, &vi
->ctrl_vid
, sizeof(vi
->ctrl_vid
));
1532 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_VLAN
,
1533 VIRTIO_NET_CTRL_VLAN_ADD
, &sg
))
1534 dev_warn(&dev
->dev
, "Failed to add VLAN ID %d.\n", vid
);
1538 static int virtnet_vlan_rx_kill_vid(struct net_device
*dev
,
1539 __be16 proto
, u16 vid
)
1541 struct virtnet_info
*vi
= netdev_priv(dev
);
1542 struct scatterlist sg
;
1545 sg_init_one(&sg
, &vi
->ctrl_vid
, sizeof(vi
->ctrl_vid
));
1547 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_VLAN
,
1548 VIRTIO_NET_CTRL_VLAN_DEL
, &sg
))
1549 dev_warn(&dev
->dev
, "Failed to kill VLAN ID %d.\n", vid
);
1553 static void virtnet_clean_affinity(struct virtnet_info
*vi
, long hcpu
)
1557 if (vi
->affinity_hint_set
) {
1558 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1559 virtqueue_set_affinity(vi
->rq
[i
].vq
, -1);
1560 virtqueue_set_affinity(vi
->sq
[i
].vq
, -1);
1563 vi
->affinity_hint_set
= false;
1567 static void virtnet_set_affinity(struct virtnet_info
*vi
)
1572 /* In multiqueue mode, when the number of cpu is equal to the number of
1573 * queue pairs, we let the queue pairs to be private to one cpu by
1574 * setting the affinity hint to eliminate the contention.
1576 if (vi
->curr_queue_pairs
== 1 ||
1577 vi
->max_queue_pairs
!= num_online_cpus()) {
1578 virtnet_clean_affinity(vi
, -1);
1583 for_each_online_cpu(cpu
) {
1584 virtqueue_set_affinity(vi
->rq
[i
].vq
, cpu
);
1585 virtqueue_set_affinity(vi
->sq
[i
].vq
, cpu
);
1586 netif_set_xps_queue(vi
->dev
, cpumask_of(cpu
), i
);
1590 vi
->affinity_hint_set
= true;
1593 static int virtnet_cpu_online(unsigned int cpu
, struct hlist_node
*node
)
1595 struct virtnet_info
*vi
= hlist_entry_safe(node
, struct virtnet_info
,
1597 virtnet_set_affinity(vi
);
1601 static int virtnet_cpu_dead(unsigned int cpu
, struct hlist_node
*node
)
1603 struct virtnet_info
*vi
= hlist_entry_safe(node
, struct virtnet_info
,
1605 virtnet_set_affinity(vi
);
1609 static int virtnet_cpu_down_prep(unsigned int cpu
, struct hlist_node
*node
)
1611 struct virtnet_info
*vi
= hlist_entry_safe(node
, struct virtnet_info
,
1614 virtnet_clean_affinity(vi
, cpu
);
1618 static enum cpuhp_state virtionet_online
;
1620 static int virtnet_cpu_notif_add(struct virtnet_info
*vi
)
1624 ret
= cpuhp_state_add_instance_nocalls(virtionet_online
, &vi
->node
);
1627 ret
= cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD
,
1631 cpuhp_state_remove_instance_nocalls(virtionet_online
, &vi
->node
);
1635 static void virtnet_cpu_notif_remove(struct virtnet_info
*vi
)
1637 cpuhp_state_remove_instance_nocalls(virtionet_online
, &vi
->node
);
1638 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD
,
1642 static void virtnet_get_ringparam(struct net_device
*dev
,
1643 struct ethtool_ringparam
*ring
)
1645 struct virtnet_info
*vi
= netdev_priv(dev
);
1647 ring
->rx_max_pending
= virtqueue_get_vring_size(vi
->rq
[0].vq
);
1648 ring
->tx_max_pending
= virtqueue_get_vring_size(vi
->sq
[0].vq
);
1649 ring
->rx_pending
= ring
->rx_max_pending
;
1650 ring
->tx_pending
= ring
->tx_max_pending
;
1654 static void virtnet_get_drvinfo(struct net_device
*dev
,
1655 struct ethtool_drvinfo
*info
)
1657 struct virtnet_info
*vi
= netdev_priv(dev
);
1658 struct virtio_device
*vdev
= vi
->vdev
;
1660 strlcpy(info
->driver
, KBUILD_MODNAME
, sizeof(info
->driver
));
1661 strlcpy(info
->version
, VIRTNET_DRIVER_VERSION
, sizeof(info
->version
));
1662 strlcpy(info
->bus_info
, virtio_bus_name(vdev
), sizeof(info
->bus_info
));
1666 /* TODO: Eliminate OOO packets during switching */
1667 static int virtnet_set_channels(struct net_device
*dev
,
1668 struct ethtool_channels
*channels
)
1670 struct virtnet_info
*vi
= netdev_priv(dev
);
1671 u16 queue_pairs
= channels
->combined_count
;
1674 /* We don't support separate rx/tx channels.
1675 * We don't allow setting 'other' channels.
1677 if (channels
->rx_count
|| channels
->tx_count
|| channels
->other_count
)
1680 if (queue_pairs
> vi
->max_queue_pairs
|| queue_pairs
== 0)
1683 /* For now we don't support modifying channels while XDP is loaded
1684 * also when XDP is loaded all RX queues have XDP programs so we only
1685 * need to check a single RX queue.
1687 if (vi
->rq
[0].xdp_prog
)
1691 err
= _virtnet_set_queues(vi
, queue_pairs
);
1693 netif_set_real_num_tx_queues(dev
, queue_pairs
);
1694 netif_set_real_num_rx_queues(dev
, queue_pairs
);
1696 virtnet_set_affinity(vi
);
1703 static void virtnet_get_channels(struct net_device
*dev
,
1704 struct ethtool_channels
*channels
)
1706 struct virtnet_info
*vi
= netdev_priv(dev
);
1708 channels
->combined_count
= vi
->curr_queue_pairs
;
1709 channels
->max_combined
= vi
->max_queue_pairs
;
1710 channels
->max_other
= 0;
1711 channels
->rx_count
= 0;
1712 channels
->tx_count
= 0;
1713 channels
->other_count
= 0;
1716 /* Check if the user is trying to change anything besides speed/duplex */
1718 virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings
*cmd
)
1720 struct ethtool_link_ksettings diff1
= *cmd
;
1721 struct ethtool_link_ksettings diff2
= {};
1723 /* cmd is always set so we need to clear it, validate the port type
1724 * and also without autonegotiation we can ignore advertising
1726 diff1
.base
.speed
= 0;
1727 diff2
.base
.port
= PORT_OTHER
;
1728 ethtool_link_ksettings_zero_link_mode(&diff1
, advertising
);
1729 diff1
.base
.duplex
= 0;
1731 diff1
.base
.link_mode_masks_nwords
= 0;
1733 return !memcmp(&diff1
.base
, &diff2
.base
, sizeof(diff1
.base
)) &&
1734 bitmap_empty(diff1
.link_modes
.supported
,
1735 __ETHTOOL_LINK_MODE_MASK_NBITS
) &&
1736 bitmap_empty(diff1
.link_modes
.advertising
,
1737 __ETHTOOL_LINK_MODE_MASK_NBITS
) &&
1738 bitmap_empty(diff1
.link_modes
.lp_advertising
,
1739 __ETHTOOL_LINK_MODE_MASK_NBITS
);
1742 static int virtnet_set_link_ksettings(struct net_device
*dev
,
1743 const struct ethtool_link_ksettings
*cmd
)
1745 struct virtnet_info
*vi
= netdev_priv(dev
);
1748 speed
= cmd
->base
.speed
;
1749 /* don't allow custom speed and duplex */
1750 if (!ethtool_validate_speed(speed
) ||
1751 !ethtool_validate_duplex(cmd
->base
.duplex
) ||
1752 !virtnet_validate_ethtool_cmd(cmd
))
1755 vi
->duplex
= cmd
->base
.duplex
;
1760 static int virtnet_get_link_ksettings(struct net_device
*dev
,
1761 struct ethtool_link_ksettings
*cmd
)
1763 struct virtnet_info
*vi
= netdev_priv(dev
);
1765 cmd
->base
.speed
= vi
->speed
;
1766 cmd
->base
.duplex
= vi
->duplex
;
1767 cmd
->base
.port
= PORT_OTHER
;
1772 static void virtnet_init_settings(struct net_device
*dev
)
1774 struct virtnet_info
*vi
= netdev_priv(dev
);
1776 vi
->speed
= SPEED_UNKNOWN
;
1777 vi
->duplex
= DUPLEX_UNKNOWN
;
1780 static const struct ethtool_ops virtnet_ethtool_ops
= {
1781 .get_drvinfo
= virtnet_get_drvinfo
,
1782 .get_link
= ethtool_op_get_link
,
1783 .get_ringparam
= virtnet_get_ringparam
,
1784 .set_channels
= virtnet_set_channels
,
1785 .get_channels
= virtnet_get_channels
,
1786 .get_ts_info
= ethtool_op_get_ts_info
,
1787 .get_link_ksettings
= virtnet_get_link_ksettings
,
1788 .set_link_ksettings
= virtnet_set_link_ksettings
,
1791 static void virtnet_freeze_down(struct virtio_device
*vdev
)
1793 struct virtnet_info
*vi
= vdev
->priv
;
1796 /* Make sure no work handler is accessing the device */
1797 flush_work(&vi
->config_work
);
1799 netif_device_detach(vi
->dev
);
1800 cancel_delayed_work_sync(&vi
->refill
);
1802 if (netif_running(vi
->dev
)) {
1803 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1804 napi_disable(&vi
->rq
[i
].napi
);
1805 virtnet_napi_tx_disable(&vi
->sq
[i
].napi
);
1810 static int init_vqs(struct virtnet_info
*vi
);
1811 static void _remove_vq_common(struct virtnet_info
*vi
);
1813 static int virtnet_restore_up(struct virtio_device
*vdev
)
1815 struct virtnet_info
*vi
= vdev
->priv
;
1822 virtio_device_ready(vdev
);
1824 if (netif_running(vi
->dev
)) {
1825 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++)
1826 if (!try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
))
1827 schedule_delayed_work(&vi
->refill
, 0);
1829 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1830 virtnet_napi_enable(vi
->rq
[i
].vq
, &vi
->rq
[i
].napi
);
1831 virtnet_napi_tx_enable(vi
, vi
->sq
[i
].vq
,
1836 netif_device_attach(vi
->dev
);
1840 static int virtnet_reset(struct virtnet_info
*vi
, int curr_qp
, int xdp_qp
)
1842 struct virtio_device
*dev
= vi
->vdev
;
1845 virtio_config_disable(dev
);
1846 dev
->failed
= dev
->config
->get_status(dev
) & VIRTIO_CONFIG_S_FAILED
;
1847 virtnet_freeze_down(dev
);
1848 _remove_vq_common(vi
);
1850 virtio_add_status(dev
, VIRTIO_CONFIG_S_ACKNOWLEDGE
);
1851 virtio_add_status(dev
, VIRTIO_CONFIG_S_DRIVER
);
1853 ret
= virtio_finalize_features(dev
);
1857 vi
->xdp_queue_pairs
= xdp_qp
;
1858 ret
= virtnet_restore_up(dev
);
1861 ret
= _virtnet_set_queues(vi
, curr_qp
);
1865 virtio_add_status(dev
, VIRTIO_CONFIG_S_DRIVER_OK
);
1866 virtio_config_enable(dev
);
1869 virtio_add_status(dev
, VIRTIO_CONFIG_S_FAILED
);
1873 static int virtnet_xdp_set(struct net_device
*dev
, struct bpf_prog
*prog
,
1874 struct netlink_ext_ack
*extack
)
1876 unsigned long int max_sz
= PAGE_SIZE
- sizeof(struct padded_vnet_hdr
);
1877 struct virtnet_info
*vi
= netdev_priv(dev
);
1878 struct bpf_prog
*old_prog
;
1879 u16 xdp_qp
= 0, curr_qp
;
1882 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_TSO4
) ||
1883 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_TSO6
) ||
1884 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_ECN
) ||
1885 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_UFO
)) {
1886 NL_SET_ERR_MSG_MOD(extack
, "Can't set XDP while host is implementing LRO, disable LRO first");
1890 if (vi
->mergeable_rx_bufs
&& !vi
->any_header_sg
) {
1891 NL_SET_ERR_MSG_MOD(extack
, "XDP expects header/data in single page, any_header_sg required");
1895 if (dev
->mtu
> max_sz
) {
1896 NL_SET_ERR_MSG_MOD(extack
, "MTU too large to enable XDP");
1897 netdev_warn(dev
, "XDP requires MTU less than %lu\n", max_sz
);
1901 curr_qp
= vi
->curr_queue_pairs
- vi
->xdp_queue_pairs
;
1903 xdp_qp
= nr_cpu_ids
;
1905 /* XDP requires extra queues for XDP_TX */
1906 if (curr_qp
+ xdp_qp
> vi
->max_queue_pairs
) {
1907 NL_SET_ERR_MSG_MOD(extack
, "Too few free TX rings available");
1908 netdev_warn(dev
, "request %i queues but max is %i\n",
1909 curr_qp
+ xdp_qp
, vi
->max_queue_pairs
);
1914 prog
= bpf_prog_add(prog
, vi
->max_queue_pairs
- 1);
1916 return PTR_ERR(prog
);
1919 /* Changing the headroom in buffers is a disruptive operation because
1920 * existing buffers must be flushed and reallocated. This will happen
1921 * when a xdp program is initially added or xdp is disabled by removing
1922 * the xdp program resulting in number of XDP queues changing.
1924 if (vi
->xdp_queue_pairs
!= xdp_qp
) {
1925 err
= virtnet_reset(vi
, curr_qp
+ xdp_qp
, xdp_qp
);
1927 dev_warn(&dev
->dev
, "XDP reset failure.\n");
1928 goto virtio_reset_err
;
1932 netif_set_real_num_rx_queues(dev
, curr_qp
+ xdp_qp
);
1934 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1935 old_prog
= rtnl_dereference(vi
->rq
[i
].xdp_prog
);
1936 rcu_assign_pointer(vi
->rq
[i
].xdp_prog
, prog
);
1938 bpf_prog_put(old_prog
);
1944 /* On reset error do our best to unwind XDP changes inflight and return
1945 * error up to user space for resolution. The underlying reset hung on
1946 * us so not much we can do here.
1949 bpf_prog_sub(prog
, vi
->max_queue_pairs
- 1);
1953 static bool virtnet_xdp_query(struct net_device
*dev
)
1955 struct virtnet_info
*vi
= netdev_priv(dev
);
1958 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1959 if (vi
->rq
[i
].xdp_prog
)
1965 static int virtnet_xdp(struct net_device
*dev
, struct netdev_xdp
*xdp
)
1967 switch (xdp
->command
) {
1968 case XDP_SETUP_PROG
:
1969 return virtnet_xdp_set(dev
, xdp
->prog
, xdp
->extack
);
1970 case XDP_QUERY_PROG
:
1971 xdp
->prog_attached
= virtnet_xdp_query(dev
);
1978 static const struct net_device_ops virtnet_netdev
= {
1979 .ndo_open
= virtnet_open
,
1980 .ndo_stop
= virtnet_close
,
1981 .ndo_start_xmit
= start_xmit
,
1982 .ndo_validate_addr
= eth_validate_addr
,
1983 .ndo_set_mac_address
= virtnet_set_mac_address
,
1984 .ndo_set_rx_mode
= virtnet_set_rx_mode
,
1985 .ndo_get_stats64
= virtnet_stats
,
1986 .ndo_vlan_rx_add_vid
= virtnet_vlan_rx_add_vid
,
1987 .ndo_vlan_rx_kill_vid
= virtnet_vlan_rx_kill_vid
,
1988 #ifdef CONFIG_NET_POLL_CONTROLLER
1989 .ndo_poll_controller
= virtnet_netpoll
,
1991 .ndo_xdp
= virtnet_xdp
,
1992 .ndo_features_check
= passthru_features_check
,
1995 static void virtnet_config_changed_work(struct work_struct
*work
)
1997 struct virtnet_info
*vi
=
1998 container_of(work
, struct virtnet_info
, config_work
);
2001 if (virtio_cread_feature(vi
->vdev
, VIRTIO_NET_F_STATUS
,
2002 struct virtio_net_config
, status
, &v
) < 0)
2005 if (v
& VIRTIO_NET_S_ANNOUNCE
) {
2006 netdev_notify_peers(vi
->dev
);
2007 virtnet_ack_link_announce(vi
);
2010 /* Ignore unknown (future) status bits */
2011 v
&= VIRTIO_NET_S_LINK_UP
;
2013 if (vi
->status
== v
)
2018 if (vi
->status
& VIRTIO_NET_S_LINK_UP
) {
2019 netif_carrier_on(vi
->dev
);
2020 netif_tx_wake_all_queues(vi
->dev
);
2022 netif_carrier_off(vi
->dev
);
2023 netif_tx_stop_all_queues(vi
->dev
);
2027 static void virtnet_config_changed(struct virtio_device
*vdev
)
2029 struct virtnet_info
*vi
= vdev
->priv
;
2031 schedule_work(&vi
->config_work
);
2034 static void virtnet_free_queues(struct virtnet_info
*vi
)
2038 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2039 napi_hash_del(&vi
->rq
[i
].napi
);
2040 netif_napi_del(&vi
->rq
[i
].napi
);
2041 netif_napi_del(&vi
->sq
[i
].napi
);
2044 /* We called napi_hash_del() before netif_napi_del(),
2045 * we need to respect an RCU grace period before freeing vi->rq
2053 static void _free_receive_bufs(struct virtnet_info
*vi
)
2055 struct bpf_prog
*old_prog
;
2058 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2059 while (vi
->rq
[i
].pages
)
2060 __free_pages(get_a_page(&vi
->rq
[i
], GFP_KERNEL
), 0);
2062 old_prog
= rtnl_dereference(vi
->rq
[i
].xdp_prog
);
2063 RCU_INIT_POINTER(vi
->rq
[i
].xdp_prog
, NULL
);
2065 bpf_prog_put(old_prog
);
2069 static void free_receive_bufs(struct virtnet_info
*vi
)
2072 _free_receive_bufs(vi
);
2076 static void free_receive_page_frags(struct virtnet_info
*vi
)
2079 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
2080 if (vi
->rq
[i
].alloc_frag
.page
)
2081 put_page(vi
->rq
[i
].alloc_frag
.page
);
2084 static bool is_xdp_raw_buffer_queue(struct virtnet_info
*vi
, int q
)
2086 if (q
< (vi
->curr_queue_pairs
- vi
->xdp_queue_pairs
))
2088 else if (q
< vi
->curr_queue_pairs
)
2094 static void free_unused_bufs(struct virtnet_info
*vi
)
2099 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2100 struct virtqueue
*vq
= vi
->sq
[i
].vq
;
2101 while ((buf
= virtqueue_detach_unused_buf(vq
)) != NULL
) {
2102 if (!is_xdp_raw_buffer_queue(vi
, i
))
2105 put_page(virt_to_head_page(buf
));
2109 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2110 struct virtqueue
*vq
= vi
->rq
[i
].vq
;
2112 while ((buf
= virtqueue_detach_unused_buf(vq
)) != NULL
) {
2113 if (vi
->mergeable_rx_bufs
) {
2114 put_page(virt_to_head_page(buf
));
2115 } else if (vi
->big_packets
) {
2116 give_pages(&vi
->rq
[i
], buf
);
2118 put_page(virt_to_head_page(buf
));
2124 static void virtnet_del_vqs(struct virtnet_info
*vi
)
2126 struct virtio_device
*vdev
= vi
->vdev
;
2128 virtnet_clean_affinity(vi
, -1);
2130 vdev
->config
->del_vqs(vdev
);
2132 virtnet_free_queues(vi
);
2135 /* How large should a single buffer be so a queue full of these can fit at
2136 * least one full packet?
2137 * Logic below assumes the mergeable buffer header is used.
2139 static unsigned int mergeable_min_buf_len(struct virtnet_info
*vi
, struct virtqueue
*vq
)
2141 const unsigned int hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
2142 unsigned int rq_size
= virtqueue_get_vring_size(vq
);
2143 unsigned int packet_len
= vi
->big_packets
? IP_MAX_MTU
: vi
->dev
->max_mtu
;
2144 unsigned int buf_len
= hdr_len
+ ETH_HLEN
+ VLAN_HLEN
+ packet_len
;
2145 unsigned int min_buf_len
= DIV_ROUND_UP(buf_len
, rq_size
);
2147 return max(max(min_buf_len
, hdr_len
) - hdr_len
,
2148 (unsigned int)GOOD_PACKET_LEN
);
2151 static int virtnet_find_vqs(struct virtnet_info
*vi
)
2153 vq_callback_t
**callbacks
;
2154 struct virtqueue
**vqs
;
2160 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2161 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2162 * possible control vq.
2164 total_vqs
= vi
->max_queue_pairs
* 2 +
2165 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VQ
);
2167 /* Allocate space for find_vqs parameters */
2168 vqs
= kzalloc(total_vqs
* sizeof(*vqs
), GFP_KERNEL
);
2171 callbacks
= kmalloc(total_vqs
* sizeof(*callbacks
), GFP_KERNEL
);
2174 names
= kmalloc(total_vqs
* sizeof(*names
), GFP_KERNEL
);
2177 if (vi
->mergeable_rx_bufs
) {
2178 ctx
= kzalloc(total_vqs
* sizeof(*ctx
), GFP_KERNEL
);
2185 /* Parameters for control virtqueue, if any */
2187 callbacks
[total_vqs
- 1] = NULL
;
2188 names
[total_vqs
- 1] = "control";
2191 /* Allocate/initialize parameters for send/receive virtqueues */
2192 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2193 callbacks
[rxq2vq(i
)] = skb_recv_done
;
2194 callbacks
[txq2vq(i
)] = skb_xmit_done
;
2195 sprintf(vi
->rq
[i
].name
, "input.%d", i
);
2196 sprintf(vi
->sq
[i
].name
, "output.%d", i
);
2197 names
[rxq2vq(i
)] = vi
->rq
[i
].name
;
2198 names
[txq2vq(i
)] = vi
->sq
[i
].name
;
2200 ctx
[rxq2vq(i
)] = true;
2203 ret
= vi
->vdev
->config
->find_vqs(vi
->vdev
, total_vqs
, vqs
, callbacks
,
2209 vi
->cvq
= vqs
[total_vqs
- 1];
2210 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VLAN
))
2211 vi
->dev
->features
|= NETIF_F_HW_VLAN_CTAG_FILTER
;
2214 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2215 vi
->rq
[i
].vq
= vqs
[rxq2vq(i
)];
2216 vi
->rq
[i
].min_buf_len
= mergeable_min_buf_len(vi
, vi
->rq
[i
].vq
);
2217 vi
->sq
[i
].vq
= vqs
[txq2vq(i
)];
2238 static int virtnet_alloc_queues(struct virtnet_info
*vi
)
2242 vi
->sq
= kzalloc(sizeof(*vi
->sq
) * vi
->max_queue_pairs
, GFP_KERNEL
);
2245 vi
->rq
= kzalloc(sizeof(*vi
->rq
) * vi
->max_queue_pairs
, GFP_KERNEL
);
2249 INIT_DELAYED_WORK(&vi
->refill
, refill_work
);
2250 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2251 vi
->rq
[i
].pages
= NULL
;
2252 netif_napi_add(vi
->dev
, &vi
->rq
[i
].napi
, virtnet_poll
,
2254 netif_tx_napi_add(vi
->dev
, &vi
->sq
[i
].napi
, virtnet_poll_tx
,
2255 napi_tx
? napi_weight
: 0);
2257 sg_init_table(vi
->rq
[i
].sg
, ARRAY_SIZE(vi
->rq
[i
].sg
));
2258 ewma_pkt_len_init(&vi
->rq
[i
].mrg_avg_pkt_len
);
2259 sg_init_table(vi
->sq
[i
].sg
, ARRAY_SIZE(vi
->sq
[i
].sg
));
2270 static int init_vqs(struct virtnet_info
*vi
)
2274 /* Allocate send & receive queues */
2275 ret
= virtnet_alloc_queues(vi
);
2279 ret
= virtnet_find_vqs(vi
);
2284 virtnet_set_affinity(vi
);
2290 virtnet_free_queues(vi
);
2296 static ssize_t
mergeable_rx_buffer_size_show(struct netdev_rx_queue
*queue
,
2297 struct rx_queue_attribute
*attribute
, char *buf
)
2299 struct virtnet_info
*vi
= netdev_priv(queue
->dev
);
2300 unsigned int queue_index
= get_netdev_rx_queue_index(queue
);
2301 struct ewma_pkt_len
*avg
;
2303 BUG_ON(queue_index
>= vi
->max_queue_pairs
);
2304 avg
= &vi
->rq
[queue_index
].mrg_avg_pkt_len
;
2305 return sprintf(buf
, "%u\n",
2306 get_mergeable_buf_len(&vi
->rq
[queue_index
], avg
));
2309 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute
=
2310 __ATTR_RO(mergeable_rx_buffer_size
);
2312 static struct attribute
*virtio_net_mrg_rx_attrs
[] = {
2313 &mergeable_rx_buffer_size_attribute
.attr
,
2317 static const struct attribute_group virtio_net_mrg_rx_group
= {
2318 .name
= "virtio_net",
2319 .attrs
= virtio_net_mrg_rx_attrs
2323 static bool virtnet_fail_on_feature(struct virtio_device
*vdev
,
2325 const char *fname
, const char *dname
)
2327 if (!virtio_has_feature(vdev
, fbit
))
2330 dev_err(&vdev
->dev
, "device advertises feature %s but not %s",
2336 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2337 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2339 static bool virtnet_validate_features(struct virtio_device
*vdev
)
2341 if (!virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
) &&
2342 (VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_RX
,
2343 "VIRTIO_NET_F_CTRL_VQ") ||
2344 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_VLAN
,
2345 "VIRTIO_NET_F_CTRL_VQ") ||
2346 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_GUEST_ANNOUNCE
,
2347 "VIRTIO_NET_F_CTRL_VQ") ||
2348 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_MQ
, "VIRTIO_NET_F_CTRL_VQ") ||
2349 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_MAC_ADDR
,
2350 "VIRTIO_NET_F_CTRL_VQ"))) {
2357 #define MIN_MTU ETH_MIN_MTU
2358 #define MAX_MTU ETH_MAX_MTU
2360 static int virtnet_validate(struct virtio_device
*vdev
)
2362 if (!vdev
->config
->get
) {
2363 dev_err(&vdev
->dev
, "%s failure: config access disabled\n",
2368 if (!virtnet_validate_features(vdev
))
2371 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MTU
)) {
2372 int mtu
= virtio_cread16(vdev
,
2373 offsetof(struct virtio_net_config
,
2376 __virtio_clear_bit(vdev
, VIRTIO_NET_F_MTU
);
2382 static int virtnet_probe(struct virtio_device
*vdev
)
2385 struct net_device
*dev
;
2386 struct virtnet_info
*vi
;
2387 u16 max_queue_pairs
;
2390 /* Find if host supports multiqueue virtio_net device */
2391 err
= virtio_cread_feature(vdev
, VIRTIO_NET_F_MQ
,
2392 struct virtio_net_config
,
2393 max_virtqueue_pairs
, &max_queue_pairs
);
2395 /* We need at least 2 queue's */
2396 if (err
|| max_queue_pairs
< VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN
||
2397 max_queue_pairs
> VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX
||
2398 !virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
))
2399 max_queue_pairs
= 1;
2401 /* Allocate ourselves a network device with room for our info */
2402 dev
= alloc_etherdev_mq(sizeof(struct virtnet_info
), max_queue_pairs
);
2406 /* Set up network device as normal. */
2407 dev
->priv_flags
|= IFF_UNICAST_FLT
| IFF_LIVE_ADDR_CHANGE
;
2408 dev
->netdev_ops
= &virtnet_netdev
;
2409 dev
->features
= NETIF_F_HIGHDMA
;
2411 dev
->ethtool_ops
= &virtnet_ethtool_ops
;
2412 SET_NETDEV_DEV(dev
, &vdev
->dev
);
2414 /* Do we support "hardware" checksums? */
2415 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CSUM
)) {
2416 /* This opens up the world of extra features. */
2417 dev
->hw_features
|= NETIF_F_HW_CSUM
| NETIF_F_SG
;
2419 dev
->features
|= NETIF_F_HW_CSUM
| NETIF_F_SG
;
2421 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GSO
)) {
2422 dev
->hw_features
|= NETIF_F_TSO
| NETIF_F_UFO
2423 | NETIF_F_TSO_ECN
| NETIF_F_TSO6
;
2425 /* Individual feature bits: what can host handle? */
2426 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_TSO4
))
2427 dev
->hw_features
|= NETIF_F_TSO
;
2428 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_TSO6
))
2429 dev
->hw_features
|= NETIF_F_TSO6
;
2430 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_ECN
))
2431 dev
->hw_features
|= NETIF_F_TSO_ECN
;
2432 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_UFO
))
2433 dev
->hw_features
|= NETIF_F_UFO
;
2435 dev
->features
|= NETIF_F_GSO_ROBUST
;
2438 dev
->features
|= dev
->hw_features
& (NETIF_F_ALL_TSO
|NETIF_F_UFO
);
2439 /* (!csum && gso) case will be fixed by register_netdev() */
2441 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_CSUM
))
2442 dev
->features
|= NETIF_F_RXCSUM
;
2444 dev
->vlan_features
= dev
->features
;
2446 /* MTU range: 68 - 65535 */
2447 dev
->min_mtu
= MIN_MTU
;
2448 dev
->max_mtu
= MAX_MTU
;
2450 /* Configuration may specify what MAC to use. Otherwise random. */
2451 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MAC
))
2452 virtio_cread_bytes(vdev
,
2453 offsetof(struct virtio_net_config
, mac
),
2454 dev
->dev_addr
, dev
->addr_len
);
2456 eth_hw_addr_random(dev
);
2458 /* Set up our device-specific information */
2459 vi
= netdev_priv(dev
);
2463 vi
->stats
= alloc_percpu(struct virtnet_stats
);
2465 if (vi
->stats
== NULL
)
2468 for_each_possible_cpu(i
) {
2469 struct virtnet_stats
*virtnet_stats
;
2470 virtnet_stats
= per_cpu_ptr(vi
->stats
, i
);
2471 u64_stats_init(&virtnet_stats
->tx_syncp
);
2472 u64_stats_init(&virtnet_stats
->rx_syncp
);
2475 INIT_WORK(&vi
->config_work
, virtnet_config_changed_work
);
2477 /* If we can receive ANY GSO packets, we must allocate large ones. */
2478 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_TSO4
) ||
2479 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_TSO6
) ||
2480 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_ECN
) ||
2481 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_UFO
))
2482 vi
->big_packets
= true;
2484 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MRG_RXBUF
))
2485 vi
->mergeable_rx_bufs
= true;
2487 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MRG_RXBUF
) ||
2488 virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
))
2489 vi
->hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
2491 vi
->hdr_len
= sizeof(struct virtio_net_hdr
);
2493 if (virtio_has_feature(vdev
, VIRTIO_F_ANY_LAYOUT
) ||
2494 virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
))
2495 vi
->any_header_sg
= true;
2497 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
))
2500 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MTU
)) {
2501 mtu
= virtio_cread16(vdev
,
2502 offsetof(struct virtio_net_config
,
2504 if (mtu
< dev
->min_mtu
) {
2505 /* Should never trigger: MTU was previously validated
2506 * in virtnet_validate.
2508 dev_err(&vdev
->dev
, "device MTU appears to have changed "
2509 "it is now %d < %d", mtu
, dev
->min_mtu
);
2516 /* TODO: size buffers correctly in this case. */
2517 if (dev
->mtu
> ETH_DATA_LEN
)
2518 vi
->big_packets
= true;
2521 if (vi
->any_header_sg
)
2522 dev
->needed_headroom
= vi
->hdr_len
;
2524 /* Enable multiqueue by default */
2525 if (num_online_cpus() >= max_queue_pairs
)
2526 vi
->curr_queue_pairs
= max_queue_pairs
;
2528 vi
->curr_queue_pairs
= num_online_cpus();
2529 vi
->max_queue_pairs
= max_queue_pairs
;
2531 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
2537 if (vi
->mergeable_rx_bufs
)
2538 dev
->sysfs_rx_queue_group
= &virtio_net_mrg_rx_group
;
2540 netif_set_real_num_tx_queues(dev
, vi
->curr_queue_pairs
);
2541 netif_set_real_num_rx_queues(dev
, vi
->curr_queue_pairs
);
2543 virtnet_init_settings(dev
);
2545 err
= register_netdev(dev
);
2547 pr_debug("virtio_net: registering device failed\n");
2551 virtio_device_ready(vdev
);
2553 err
= virtnet_cpu_notif_add(vi
);
2555 pr_debug("virtio_net: registering cpu notifier failed\n");
2556 goto free_unregister_netdev
;
2559 virtnet_set_queues(vi
, vi
->curr_queue_pairs
);
2561 /* Assume link up if device can't report link status,
2562 otherwise get link status from config. */
2563 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_STATUS
)) {
2564 netif_carrier_off(dev
);
2565 schedule_work(&vi
->config_work
);
2567 vi
->status
= VIRTIO_NET_S_LINK_UP
;
2568 netif_carrier_on(dev
);
2571 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
2572 dev
->name
, max_queue_pairs
);
2576 free_unregister_netdev
:
2577 vi
->vdev
->config
->reset(vdev
);
2579 unregister_netdev(dev
);
2581 cancel_delayed_work_sync(&vi
->refill
);
2582 free_receive_page_frags(vi
);
2583 virtnet_del_vqs(vi
);
2585 free_percpu(vi
->stats
);
2591 static void _remove_vq_common(struct virtnet_info
*vi
)
2593 vi
->vdev
->config
->reset(vi
->vdev
);
2594 free_unused_bufs(vi
);
2595 _free_receive_bufs(vi
);
2596 free_receive_page_frags(vi
);
2597 virtnet_del_vqs(vi
);
2600 static void remove_vq_common(struct virtnet_info
*vi
)
2602 vi
->vdev
->config
->reset(vi
->vdev
);
2604 /* Free unused buffers in both send and recv, if any. */
2605 free_unused_bufs(vi
);
2607 free_receive_bufs(vi
);
2609 free_receive_page_frags(vi
);
2611 virtnet_del_vqs(vi
);
2614 static void virtnet_remove(struct virtio_device
*vdev
)
2616 struct virtnet_info
*vi
= vdev
->priv
;
2618 virtnet_cpu_notif_remove(vi
);
2620 /* Make sure no work handler is accessing the device. */
2621 flush_work(&vi
->config_work
);
2623 unregister_netdev(vi
->dev
);
2625 remove_vq_common(vi
);
2627 free_percpu(vi
->stats
);
2628 free_netdev(vi
->dev
);
2631 #ifdef CONFIG_PM_SLEEP
2632 static int virtnet_freeze(struct virtio_device
*vdev
)
2634 struct virtnet_info
*vi
= vdev
->priv
;
2636 virtnet_cpu_notif_remove(vi
);
2637 virtnet_freeze_down(vdev
);
2638 remove_vq_common(vi
);
2643 static int virtnet_restore(struct virtio_device
*vdev
)
2645 struct virtnet_info
*vi
= vdev
->priv
;
2648 err
= virtnet_restore_up(vdev
);
2651 virtnet_set_queues(vi
, vi
->curr_queue_pairs
);
2653 err
= virtnet_cpu_notif_add(vi
);
2661 static struct virtio_device_id id_table
[] = {
2662 { VIRTIO_ID_NET
, VIRTIO_DEV_ANY_ID
},
2666 #define VIRTNET_FEATURES \
2667 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
2669 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
2670 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
2671 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
2672 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
2673 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
2674 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
2675 VIRTIO_NET_F_CTRL_MAC_ADDR, \
2678 static unsigned int features
[] = {
2682 static unsigned int features_legacy
[] = {
2685 VIRTIO_F_ANY_LAYOUT
,
2688 static struct virtio_driver virtio_net_driver
= {
2689 .feature_table
= features
,
2690 .feature_table_size
= ARRAY_SIZE(features
),
2691 .feature_table_legacy
= features_legacy
,
2692 .feature_table_size_legacy
= ARRAY_SIZE(features_legacy
),
2693 .driver
.name
= KBUILD_MODNAME
,
2694 .driver
.owner
= THIS_MODULE
,
2695 .id_table
= id_table
,
2696 .validate
= virtnet_validate
,
2697 .probe
= virtnet_probe
,
2698 .remove
= virtnet_remove
,
2699 .config_changed
= virtnet_config_changed
,
2700 #ifdef CONFIG_PM_SLEEP
2701 .freeze
= virtnet_freeze
,
2702 .restore
= virtnet_restore
,
2706 static __init
int virtio_net_driver_init(void)
2710 ret
= cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN
, "virtio/net:online",
2712 virtnet_cpu_down_prep
);
2715 virtionet_online
= ret
;
2716 ret
= cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD
, "virtio/net:dead",
2717 NULL
, virtnet_cpu_dead
);
2721 ret
= register_virtio_driver(&virtio_net_driver
);
2726 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD
);
2728 cpuhp_remove_multi_state(virtionet_online
);
2732 module_init(virtio_net_driver_init
);
2734 static __exit
void virtio_net_driver_exit(void)
2736 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD
);
2737 cpuhp_remove_multi_state(virtionet_online
);
2738 unregister_virtio_driver(&virtio_net_driver
);
2740 module_exit(virtio_net_driver_exit
);
2742 MODULE_DEVICE_TABLE(virtio
, id_table
);
2743 MODULE_DESCRIPTION("Virtio network driver");
2744 MODULE_LICENSE("GPL");