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 static const unsigned long guest_offloads
[] = {
61 VIRTIO_NET_F_GUEST_TSO4
,
62 VIRTIO_NET_F_GUEST_TSO6
,
63 VIRTIO_NET_F_GUEST_ECN
,
64 VIRTIO_NET_F_GUEST_UFO
67 struct virtnet_stats
{
68 struct u64_stats_sync tx_syncp
;
69 struct u64_stats_sync rx_syncp
;
77 /* Internal representation of a send virtqueue */
79 /* Virtqueue associated with this send _queue */
82 /* TX: fragments + linear part + virtio header */
83 struct scatterlist sg
[MAX_SKB_FRAGS
+ 2];
85 /* Name of the send queue: output.$index */
88 struct napi_struct napi
;
91 /* Internal representation of a receive virtqueue */
92 struct receive_queue
{
93 /* Virtqueue associated with this receive_queue */
96 struct napi_struct napi
;
98 struct bpf_prog __rcu
*xdp_prog
;
100 /* Chain pages by the private ptr. */
103 /* Average packet length for mergeable receive buffers. */
104 struct ewma_pkt_len mrg_avg_pkt_len
;
106 /* Page frag for packet buffer allocation. */
107 struct page_frag alloc_frag
;
109 /* RX: fragments + linear part + virtio header */
110 struct scatterlist sg
[MAX_SKB_FRAGS
+ 2];
112 /* Min single buffer size for mergeable buffers case. */
113 unsigned int min_buf_len
;
115 /* Name of this receive queue: input.$index */
119 struct virtnet_info
{
120 struct virtio_device
*vdev
;
121 struct virtqueue
*cvq
;
122 struct net_device
*dev
;
123 struct send_queue
*sq
;
124 struct receive_queue
*rq
;
127 /* Max # of queue pairs supported by the device */
130 /* # of queue pairs currently used by the driver */
131 u16 curr_queue_pairs
;
133 /* # of XDP queue pairs currently used by the driver */
136 /* I like... big packets and I cannot lie! */
139 /* Host will merge rx buffers for big packets (shake it! shake it!) */
140 bool mergeable_rx_bufs
;
142 /* Has control virtqueue */
145 /* Host can handle any s/g split between our header and packet data */
148 /* Packet virtio header size */
151 /* Active statistics */
152 struct virtnet_stats __percpu
*stats
;
154 /* Work struct for refilling if we run low on memory. */
155 struct delayed_work refill
;
157 /* Work struct for config space updates */
158 struct work_struct config_work
;
160 /* Does the affinity hint is set for virtqueues? */
161 bool affinity_hint_set
;
163 /* CPU hotplug instances for online & dead */
164 struct hlist_node node
;
165 struct hlist_node node_dead
;
167 /* Control VQ buffers: protected by the rtnl lock */
168 struct virtio_net_ctrl_hdr ctrl_hdr
;
169 virtio_net_ctrl_ack ctrl_status
;
170 struct virtio_net_ctrl_mq ctrl_mq
;
176 /* Ethtool settings */
180 unsigned long guest_offloads
;
183 struct padded_vnet_hdr
{
184 struct virtio_net_hdr_mrg_rxbuf hdr
;
186 * hdr is in a separate sg buffer, and data sg buffer shares same page
187 * with this header sg. This padding makes next sg 16 byte aligned
193 /* Converting between virtqueue no. and kernel tx/rx queue no.
194 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
196 static int vq2txq(struct virtqueue
*vq
)
198 return (vq
->index
- 1) / 2;
201 static int txq2vq(int txq
)
206 static int vq2rxq(struct virtqueue
*vq
)
208 return vq
->index
/ 2;
211 static int rxq2vq(int rxq
)
216 static inline struct virtio_net_hdr_mrg_rxbuf
*skb_vnet_hdr(struct sk_buff
*skb
)
218 return (struct virtio_net_hdr_mrg_rxbuf
*)skb
->cb
;
222 * private is used to chain pages for big packets, put the whole
223 * most recent used list in the beginning for reuse
225 static void give_pages(struct receive_queue
*rq
, struct page
*page
)
229 /* Find end of list, sew whole thing into vi->rq.pages. */
230 for (end
= page
; end
->private; end
= (struct page
*)end
->private);
231 end
->private = (unsigned long)rq
->pages
;
235 static struct page
*get_a_page(struct receive_queue
*rq
, gfp_t gfp_mask
)
237 struct page
*p
= rq
->pages
;
240 rq
->pages
= (struct page
*)p
->private;
241 /* clear private here, it is used to chain pages */
244 p
= alloc_page(gfp_mask
);
248 static void virtqueue_napi_schedule(struct napi_struct
*napi
,
249 struct virtqueue
*vq
)
251 if (napi_schedule_prep(napi
)) {
252 virtqueue_disable_cb(vq
);
253 __napi_schedule(napi
);
257 static void virtqueue_napi_complete(struct napi_struct
*napi
,
258 struct virtqueue
*vq
, int processed
)
262 opaque
= virtqueue_enable_cb_prepare(vq
);
263 if (napi_complete_done(napi
, processed
) &&
264 unlikely(virtqueue_poll(vq
, opaque
)))
265 virtqueue_napi_schedule(napi
, vq
);
268 static void skb_xmit_done(struct virtqueue
*vq
)
270 struct virtnet_info
*vi
= vq
->vdev
->priv
;
271 struct napi_struct
*napi
= &vi
->sq
[vq2txq(vq
)].napi
;
273 /* Suppress further interrupts. */
274 virtqueue_disable_cb(vq
);
277 virtqueue_napi_schedule(napi
, vq
);
279 /* We were probably waiting for more output buffers. */
280 netif_wake_subqueue(vi
->dev
, vq2txq(vq
));
283 #define MRG_CTX_HEADER_SHIFT 22
284 static void *mergeable_len_to_ctx(unsigned int truesize
,
285 unsigned int headroom
)
287 return (void *)(unsigned long)((headroom
<< MRG_CTX_HEADER_SHIFT
) | truesize
);
290 static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx
)
292 return (unsigned long)mrg_ctx
>> MRG_CTX_HEADER_SHIFT
;
295 static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx
)
297 return (unsigned long)mrg_ctx
& ((1 << MRG_CTX_HEADER_SHIFT
) - 1);
300 /* Called from bottom half context */
301 static struct sk_buff
*page_to_skb(struct virtnet_info
*vi
,
302 struct receive_queue
*rq
,
303 struct page
*page
, unsigned int offset
,
304 unsigned int len
, unsigned int truesize
)
307 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
308 unsigned int copy
, hdr_len
, hdr_padded_len
;
311 p
= page_address(page
) + offset
;
313 /* copy small packet so we can reuse these pages for small data */
314 skb
= napi_alloc_skb(&rq
->napi
, GOOD_COPY_LEN
);
318 hdr
= skb_vnet_hdr(skb
);
320 hdr_len
= vi
->hdr_len
;
321 if (vi
->mergeable_rx_bufs
)
322 hdr_padded_len
= sizeof(*hdr
);
324 hdr_padded_len
= sizeof(struct padded_vnet_hdr
);
326 memcpy(hdr
, p
, hdr_len
);
329 offset
+= hdr_padded_len
;
333 if (copy
> skb_tailroom(skb
))
334 copy
= skb_tailroom(skb
);
335 skb_put_data(skb
, p
, copy
);
340 if (vi
->mergeable_rx_bufs
) {
342 skb_add_rx_frag(skb
, 0, page
, offset
, len
, truesize
);
349 * Verify that we can indeed put this data into a skb.
350 * This is here to handle cases when the device erroneously
351 * tries to receive more than is possible. This is usually
352 * the case of a broken device.
354 if (unlikely(len
> MAX_SKB_FRAGS
* PAGE_SIZE
)) {
355 net_dbg_ratelimited("%s: too much data\n", skb
->dev
->name
);
359 BUG_ON(offset
>= PAGE_SIZE
);
361 unsigned int frag_size
= min((unsigned)PAGE_SIZE
- offset
, len
);
362 skb_add_rx_frag(skb
, skb_shinfo(skb
)->nr_frags
, page
, offset
,
363 frag_size
, truesize
);
365 page
= (struct page
*)page
->private;
370 give_pages(rq
, page
);
375 static bool virtnet_xdp_xmit(struct virtnet_info
*vi
,
376 struct receive_queue
*rq
,
377 struct xdp_buff
*xdp
)
379 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
381 struct send_queue
*sq
;
386 qp
= vi
->curr_queue_pairs
- vi
->xdp_queue_pairs
+ smp_processor_id();
389 /* Free up any pending old buffers before queueing new ones. */
390 while ((xdp_sent
= virtqueue_get_buf(sq
->vq
, &len
)) != NULL
) {
391 struct page
*sent_page
= virt_to_head_page(xdp_sent
);
396 xdp
->data
-= vi
->hdr_len
;
397 /* Zero header and leave csum up to XDP layers */
399 memset(hdr
, 0, vi
->hdr_len
);
401 sg_init_one(sq
->sg
, xdp
->data
, xdp
->data_end
- xdp
->data
);
403 err
= virtqueue_add_outbuf(sq
->vq
, sq
->sg
, 1, xdp
->data
, GFP_ATOMIC
);
405 struct page
*page
= virt_to_head_page(xdp
->data
);
411 virtqueue_kick(sq
->vq
);
415 static unsigned int virtnet_get_headroom(struct virtnet_info
*vi
)
417 return vi
->xdp_queue_pairs
? VIRTIO_XDP_HEADROOM
: 0;
420 /* We copy the packet for XDP in the following cases:
422 * 1) Packet is scattered across multiple rx buffers.
423 * 2) Headroom space is insufficient.
425 * This is inefficient but it's a temporary condition that
426 * we hit right after XDP is enabled and until queue is refilled
427 * with large buffers with sufficient headroom - so it should affect
428 * at most queue size packets.
429 * Afterwards, the conditions to enable
430 * XDP should preclude the underlying device from sending packets
431 * across multiple buffers (num_buf > 1), and we make sure buffers
432 * have enough headroom.
434 static struct page
*xdp_linearize_page(struct receive_queue
*rq
,
441 struct page
*page
= alloc_page(GFP_ATOMIC
);
446 memcpy(page_address(page
) + page_off
, page_address(p
) + offset
, *len
);
454 buf
= virtqueue_get_buf(rq
->vq
, &buflen
);
458 p
= virt_to_head_page(buf
);
459 off
= buf
- page_address(p
);
461 /* guard against a misconfigured or uncooperative backend that
462 * is sending packet larger than the MTU.
464 if ((page_off
+ buflen
) > PAGE_SIZE
) {
469 memcpy(page_address(page
) + page_off
,
470 page_address(p
) + off
, buflen
);
475 /* Headroom does not contribute to packet length */
476 *len
= page_off
- VIRTIO_XDP_HEADROOM
;
479 __free_pages(page
, 0);
483 static struct sk_buff
*receive_small(struct net_device
*dev
,
484 struct virtnet_info
*vi
,
485 struct receive_queue
*rq
,
486 void *buf
, void *ctx
,
490 struct bpf_prog
*xdp_prog
;
491 unsigned int xdp_headroom
= (unsigned long)ctx
;
492 unsigned int header_offset
= VIRTNET_RX_PAD
+ xdp_headroom
;
493 unsigned int headroom
= vi
->hdr_len
+ header_offset
;
494 unsigned int buflen
= SKB_DATA_ALIGN(GOOD_PACKET_LEN
+ headroom
) +
495 SKB_DATA_ALIGN(sizeof(struct skb_shared_info
));
496 struct page
*page
= virt_to_head_page(buf
);
497 unsigned int delta
= 0;
498 struct page
*xdp_page
;
502 xdp_prog
= rcu_dereference(rq
->xdp_prog
);
504 struct virtio_net_hdr_mrg_rxbuf
*hdr
= buf
+ header_offset
;
509 if (unlikely(hdr
->hdr
.gso_type
|| hdr
->hdr
.flags
))
512 if (unlikely(xdp_headroom
< virtnet_get_headroom(vi
))) {
513 int offset
= buf
- page_address(page
) + header_offset
;
514 unsigned int tlen
= len
+ vi
->hdr_len
;
517 xdp_headroom
= virtnet_get_headroom(vi
);
518 header_offset
= VIRTNET_RX_PAD
+ xdp_headroom
;
519 headroom
= vi
->hdr_len
+ header_offset
;
520 buflen
= SKB_DATA_ALIGN(GOOD_PACKET_LEN
+ headroom
) +
521 SKB_DATA_ALIGN(sizeof(struct skb_shared_info
));
522 xdp_page
= xdp_linearize_page(rq
, &num_buf
, page
,
523 offset
, header_offset
,
528 buf
= page_address(xdp_page
);
533 xdp
.data_hard_start
= buf
+ VIRTNET_RX_PAD
+ vi
->hdr_len
;
534 xdp
.data
= xdp
.data_hard_start
+ xdp_headroom
;
535 xdp
.data_end
= xdp
.data
+ len
;
536 orig_data
= xdp
.data
;
537 act
= bpf_prog_run_xdp(xdp_prog
, &xdp
);
541 /* Recalculate length in case bpf program changed it */
542 delta
= orig_data
- xdp
.data
;
545 if (unlikely(!virtnet_xdp_xmit(vi
, rq
, &xdp
)))
546 trace_xdp_exception(vi
->dev
, xdp_prog
, act
);
550 bpf_warn_invalid_xdp_action(act
);
552 trace_xdp_exception(vi
->dev
, xdp_prog
, act
);
559 skb
= build_skb(buf
, buflen
);
564 skb_reserve(skb
, headroom
- delta
);
565 skb_put(skb
, len
+ delta
);
567 buf
+= header_offset
;
568 memcpy(skb_vnet_hdr(skb
), buf
, vi
->hdr_len
);
569 } /* keep zeroed vnet hdr since packet was changed by bpf */
576 dev
->stats
.rx_dropped
++;
582 static struct sk_buff
*receive_big(struct net_device
*dev
,
583 struct virtnet_info
*vi
,
584 struct receive_queue
*rq
,
588 struct page
*page
= buf
;
589 struct sk_buff
*skb
= page_to_skb(vi
, rq
, page
, 0, len
, PAGE_SIZE
);
597 dev
->stats
.rx_dropped
++;
598 give_pages(rq
, page
);
602 static struct sk_buff
*receive_mergeable(struct net_device
*dev
,
603 struct virtnet_info
*vi
,
604 struct receive_queue
*rq
,
609 struct virtio_net_hdr_mrg_rxbuf
*hdr
= buf
;
610 u16 num_buf
= virtio16_to_cpu(vi
->vdev
, hdr
->num_buffers
);
611 struct page
*page
= virt_to_head_page(buf
);
612 int offset
= buf
- page_address(page
);
613 struct sk_buff
*head_skb
, *curr_skb
;
614 struct bpf_prog
*xdp_prog
;
615 unsigned int truesize
;
616 unsigned int headroom
= mergeable_ctx_to_headroom(ctx
);
621 xdp_prog
= rcu_dereference(rq
->xdp_prog
);
623 struct page
*xdp_page
;
628 /* This happens when rx buffer size is underestimated */
629 if (unlikely(num_buf
> 1 ||
630 headroom
< virtnet_get_headroom(vi
))) {
631 /* linearize data for XDP */
632 xdp_page
= xdp_linearize_page(rq
, &num_buf
,
638 offset
= VIRTIO_XDP_HEADROOM
;
643 /* Transient failure which in theory could occur if
644 * in-flight packets from before XDP was enabled reach
645 * the receive path after XDP is loaded. In practice I
646 * was not able to create this condition.
648 if (unlikely(hdr
->hdr
.gso_type
))
651 /* Allow consuming headroom but reserve enough space to push
652 * the descriptor on if we get an XDP_TX return code.
654 data
= page_address(xdp_page
) + offset
;
655 xdp
.data_hard_start
= data
- VIRTIO_XDP_HEADROOM
+ vi
->hdr_len
;
656 xdp
.data
= data
+ vi
->hdr_len
;
657 xdp
.data_end
= xdp
.data
+ (len
- vi
->hdr_len
);
658 act
= bpf_prog_run_xdp(xdp_prog
, &xdp
);
662 /* recalculate offset to account for any header
663 * adjustments. Note other cases do not build an
664 * skb and avoid using offset
667 page_address(xdp_page
) - vi
->hdr_len
;
669 /* We can only create skb based on xdp_page. */
670 if (unlikely(xdp_page
!= page
)) {
673 head_skb
= page_to_skb(vi
, rq
, xdp_page
,
674 offset
, len
, PAGE_SIZE
);
675 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, len
);
680 if (unlikely(!virtnet_xdp_xmit(vi
, rq
, &xdp
)))
681 trace_xdp_exception(vi
->dev
, xdp_prog
, act
);
682 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, len
);
683 if (unlikely(xdp_page
!= page
))
688 bpf_warn_invalid_xdp_action(act
);
690 trace_xdp_exception(vi
->dev
, xdp_prog
, act
);
692 if (unlikely(xdp_page
!= page
))
693 __free_pages(xdp_page
, 0);
694 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, len
);
700 truesize
= mergeable_ctx_to_truesize(ctx
);
701 if (unlikely(len
> truesize
)) {
702 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
703 dev
->name
, len
, (unsigned long)ctx
);
704 dev
->stats
.rx_length_errors
++;
708 head_skb
= page_to_skb(vi
, rq
, page
, offset
, len
, truesize
);
711 if (unlikely(!curr_skb
))
716 buf
= virtqueue_get_buf_ctx(rq
->vq
, &len
, &ctx
);
717 if (unlikely(!ctx
)) {
718 pr_debug("%s: rx error: %d buffers out of %d missing\n",
720 virtio16_to_cpu(vi
->vdev
,
722 dev
->stats
.rx_length_errors
++;
726 page
= virt_to_head_page(buf
);
728 truesize
= mergeable_ctx_to_truesize(ctx
);
729 if (unlikely(len
> truesize
)) {
730 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
731 dev
->name
, len
, (unsigned long)ctx
);
732 dev
->stats
.rx_length_errors
++;
736 num_skb_frags
= skb_shinfo(curr_skb
)->nr_frags
;
737 if (unlikely(num_skb_frags
== MAX_SKB_FRAGS
)) {
738 struct sk_buff
*nskb
= alloc_skb(0, GFP_ATOMIC
);
742 if (curr_skb
== head_skb
)
743 skb_shinfo(curr_skb
)->frag_list
= nskb
;
745 curr_skb
->next
= nskb
;
747 head_skb
->truesize
+= nskb
->truesize
;
750 if (curr_skb
!= head_skb
) {
751 head_skb
->data_len
+= len
;
752 head_skb
->len
+= len
;
753 head_skb
->truesize
+= truesize
;
755 offset
= buf
- page_address(page
);
756 if (skb_can_coalesce(curr_skb
, num_skb_frags
, page
, offset
)) {
758 skb_coalesce_rx_frag(curr_skb
, num_skb_frags
- 1,
761 skb_add_rx_frag(curr_skb
, num_skb_frags
, page
,
762 offset
, len
, truesize
);
766 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, head_skb
->len
);
774 buf
= virtqueue_get_buf(rq
->vq
, &len
);
775 if (unlikely(!buf
)) {
776 pr_debug("%s: rx error: %d buffers missing\n",
778 dev
->stats
.rx_length_errors
++;
781 page
= virt_to_head_page(buf
);
785 dev
->stats
.rx_dropped
++;
786 dev_kfree_skb(head_skb
);
791 static int receive_buf(struct virtnet_info
*vi
, struct receive_queue
*rq
,
792 void *buf
, unsigned int len
, void **ctx
)
794 struct net_device
*dev
= vi
->dev
;
796 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
799 if (unlikely(len
< vi
->hdr_len
+ ETH_HLEN
)) {
800 pr_debug("%s: short packet %i\n", dev
->name
, len
);
801 dev
->stats
.rx_length_errors
++;
802 if (vi
->mergeable_rx_bufs
) {
803 put_page(virt_to_head_page(buf
));
804 } else if (vi
->big_packets
) {
807 put_page(virt_to_head_page(buf
));
812 if (vi
->mergeable_rx_bufs
)
813 skb
= receive_mergeable(dev
, vi
, rq
, buf
, ctx
, len
);
814 else if (vi
->big_packets
)
815 skb
= receive_big(dev
, vi
, rq
, buf
, len
);
817 skb
= receive_small(dev
, vi
, rq
, buf
, ctx
, len
);
822 hdr
= skb_vnet_hdr(skb
);
826 if (hdr
->hdr
.flags
& VIRTIO_NET_HDR_F_DATA_VALID
)
827 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
829 if (virtio_net_hdr_to_skb(skb
, &hdr
->hdr
,
830 virtio_is_little_endian(vi
->vdev
))) {
831 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
832 dev
->name
, hdr
->hdr
.gso_type
,
837 skb
->protocol
= eth_type_trans(skb
, dev
);
838 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
839 ntohs(skb
->protocol
), skb
->len
, skb
->pkt_type
);
841 napi_gro_receive(&rq
->napi
, skb
);
845 dev
->stats
.rx_frame_errors
++;
850 /* Unlike mergeable buffers, all buffers are allocated to the
851 * same size, except for the headroom. For this reason we do
852 * not need to use mergeable_len_to_ctx here - it is enough
853 * to store the headroom as the context ignoring the truesize.
855 static int add_recvbuf_small(struct virtnet_info
*vi
, struct receive_queue
*rq
,
858 struct page_frag
*alloc_frag
= &rq
->alloc_frag
;
860 unsigned int xdp_headroom
= virtnet_get_headroom(vi
);
861 void *ctx
= (void *)(unsigned long)xdp_headroom
;
862 int len
= vi
->hdr_len
+ VIRTNET_RX_PAD
+ GOOD_PACKET_LEN
+ xdp_headroom
;
865 len
= SKB_DATA_ALIGN(len
) +
866 SKB_DATA_ALIGN(sizeof(struct skb_shared_info
));
867 if (unlikely(!skb_page_frag_refill(len
, alloc_frag
, gfp
)))
870 buf
= (char *)page_address(alloc_frag
->page
) + alloc_frag
->offset
;
871 get_page(alloc_frag
->page
);
872 alloc_frag
->offset
+= len
;
873 sg_init_one(rq
->sg
, buf
+ VIRTNET_RX_PAD
+ xdp_headroom
,
874 vi
->hdr_len
+ GOOD_PACKET_LEN
);
875 err
= virtqueue_add_inbuf_ctx(rq
->vq
, rq
->sg
, 1, buf
, ctx
, gfp
);
877 put_page(virt_to_head_page(buf
));
881 static int add_recvbuf_big(struct virtnet_info
*vi
, struct receive_queue
*rq
,
884 struct page
*first
, *list
= NULL
;
888 sg_init_table(rq
->sg
, MAX_SKB_FRAGS
+ 2);
890 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
891 for (i
= MAX_SKB_FRAGS
+ 1; i
> 1; --i
) {
892 first
= get_a_page(rq
, gfp
);
895 give_pages(rq
, list
);
898 sg_set_buf(&rq
->sg
[i
], page_address(first
), PAGE_SIZE
);
900 /* chain new page in list head to match sg */
901 first
->private = (unsigned long)list
;
905 first
= get_a_page(rq
, gfp
);
907 give_pages(rq
, list
);
910 p
= page_address(first
);
912 /* rq->sg[0], rq->sg[1] share the same page */
913 /* a separated rq->sg[0] for header - required in case !any_header_sg */
914 sg_set_buf(&rq
->sg
[0], p
, vi
->hdr_len
);
916 /* rq->sg[1] for data packet, from offset */
917 offset
= sizeof(struct padded_vnet_hdr
);
918 sg_set_buf(&rq
->sg
[1], p
+ offset
, PAGE_SIZE
- offset
);
920 /* chain first in list head */
921 first
->private = (unsigned long)list
;
922 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, MAX_SKB_FRAGS
+ 2,
925 give_pages(rq
, first
);
930 static unsigned int get_mergeable_buf_len(struct receive_queue
*rq
,
931 struct ewma_pkt_len
*avg_pkt_len
)
933 const size_t hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
936 len
= hdr_len
+ clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len
),
937 rq
->min_buf_len
, PAGE_SIZE
- hdr_len
);
938 return ALIGN(len
, L1_CACHE_BYTES
);
941 static int add_recvbuf_mergeable(struct virtnet_info
*vi
,
942 struct receive_queue
*rq
, gfp_t gfp
)
944 struct page_frag
*alloc_frag
= &rq
->alloc_frag
;
945 unsigned int headroom
= virtnet_get_headroom(vi
);
949 unsigned int len
, hole
;
951 len
= get_mergeable_buf_len(rq
, &rq
->mrg_avg_pkt_len
);
952 if (unlikely(!skb_page_frag_refill(len
+ headroom
, alloc_frag
, gfp
)))
955 buf
= (char *)page_address(alloc_frag
->page
) + alloc_frag
->offset
;
956 buf
+= headroom
; /* advance address leaving hole at front of pkt */
957 get_page(alloc_frag
->page
);
958 alloc_frag
->offset
+= len
+ headroom
;
959 hole
= alloc_frag
->size
- alloc_frag
->offset
;
960 if (hole
< len
+ headroom
) {
961 /* To avoid internal fragmentation, if there is very likely not
962 * enough space for another buffer, add the remaining space to
963 * the current buffer.
966 alloc_frag
->offset
+= hole
;
969 sg_init_one(rq
->sg
, buf
, len
);
970 ctx
= mergeable_len_to_ctx(len
, headroom
);
971 err
= virtqueue_add_inbuf_ctx(rq
->vq
, rq
->sg
, 1, buf
, ctx
, gfp
);
973 put_page(virt_to_head_page(buf
));
979 * Returns false if we couldn't fill entirely (OOM).
981 * Normally run in the receive path, but can also be run from ndo_open
982 * before we're receiving packets, or from refill_work which is
983 * careful to disable receiving (using napi_disable).
985 static bool try_fill_recv(struct virtnet_info
*vi
, struct receive_queue
*rq
,
993 if (vi
->mergeable_rx_bufs
)
994 err
= add_recvbuf_mergeable(vi
, rq
, gfp
);
995 else if (vi
->big_packets
)
996 err
= add_recvbuf_big(vi
, rq
, gfp
);
998 err
= add_recvbuf_small(vi
, rq
, gfp
);
1000 oom
= err
== -ENOMEM
;
1003 } while (rq
->vq
->num_free
);
1004 virtqueue_kick(rq
->vq
);
1008 static void skb_recv_done(struct virtqueue
*rvq
)
1010 struct virtnet_info
*vi
= rvq
->vdev
->priv
;
1011 struct receive_queue
*rq
= &vi
->rq
[vq2rxq(rvq
)];
1013 virtqueue_napi_schedule(&rq
->napi
, rvq
);
1016 static void virtnet_napi_enable(struct virtqueue
*vq
, struct napi_struct
*napi
)
1020 /* If all buffers were filled by other side before we napi_enabled, we
1021 * won't get another interrupt, so process any outstanding packets now.
1022 * Call local_bh_enable after to trigger softIRQ processing.
1025 virtqueue_napi_schedule(napi
, vq
);
1029 static void virtnet_napi_tx_enable(struct virtnet_info
*vi
,
1030 struct virtqueue
*vq
,
1031 struct napi_struct
*napi
)
1036 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
1037 * enable the feature if this is likely affine with the transmit path.
1039 if (!vi
->affinity_hint_set
) {
1044 return virtnet_napi_enable(vq
, napi
);
1047 static void virtnet_napi_tx_disable(struct napi_struct
*napi
)
1053 static void refill_work(struct work_struct
*work
)
1055 struct virtnet_info
*vi
=
1056 container_of(work
, struct virtnet_info
, refill
.work
);
1060 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++) {
1061 struct receive_queue
*rq
= &vi
->rq
[i
];
1063 napi_disable(&rq
->napi
);
1064 still_empty
= !try_fill_recv(vi
, rq
, GFP_KERNEL
);
1065 virtnet_napi_enable(rq
->vq
, &rq
->napi
);
1067 /* In theory, this can happen: if we don't get any buffers in
1068 * we will *never* try to fill again.
1071 schedule_delayed_work(&vi
->refill
, HZ
/2);
1075 static int virtnet_receive(struct receive_queue
*rq
, int budget
)
1077 struct virtnet_info
*vi
= rq
->vq
->vdev
->priv
;
1078 unsigned int len
, received
= 0, bytes
= 0;
1080 struct virtnet_stats
*stats
= this_cpu_ptr(vi
->stats
);
1082 if (!vi
->big_packets
|| vi
->mergeable_rx_bufs
) {
1085 while (received
< budget
&&
1086 (buf
= virtqueue_get_buf_ctx(rq
->vq
, &len
, &ctx
))) {
1087 bytes
+= receive_buf(vi
, rq
, buf
, len
, ctx
);
1091 while (received
< budget
&&
1092 (buf
= virtqueue_get_buf(rq
->vq
, &len
)) != NULL
) {
1093 bytes
+= receive_buf(vi
, rq
, buf
, len
, NULL
);
1098 if (rq
->vq
->num_free
> virtqueue_get_vring_size(rq
->vq
) / 2) {
1099 if (!try_fill_recv(vi
, rq
, GFP_ATOMIC
))
1100 schedule_delayed_work(&vi
->refill
, 0);
1103 u64_stats_update_begin(&stats
->rx_syncp
);
1104 stats
->rx_bytes
+= bytes
;
1105 stats
->rx_packets
+= received
;
1106 u64_stats_update_end(&stats
->rx_syncp
);
1111 static void free_old_xmit_skbs(struct send_queue
*sq
)
1113 struct sk_buff
*skb
;
1115 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
1116 struct virtnet_stats
*stats
= this_cpu_ptr(vi
->stats
);
1117 unsigned int packets
= 0;
1118 unsigned int bytes
= 0;
1120 while ((skb
= virtqueue_get_buf(sq
->vq
, &len
)) != NULL
) {
1121 pr_debug("Sent skb %p\n", skb
);
1126 dev_consume_skb_any(skb
);
1129 /* Avoid overhead when no packets have been processed
1130 * happens when called speculatively from start_xmit.
1135 u64_stats_update_begin(&stats
->tx_syncp
);
1136 stats
->tx_bytes
+= bytes
;
1137 stats
->tx_packets
+= packets
;
1138 u64_stats_update_end(&stats
->tx_syncp
);
1141 static void virtnet_poll_cleantx(struct receive_queue
*rq
)
1143 struct virtnet_info
*vi
= rq
->vq
->vdev
->priv
;
1144 unsigned int index
= vq2rxq(rq
->vq
);
1145 struct send_queue
*sq
= &vi
->sq
[index
];
1146 struct netdev_queue
*txq
= netdev_get_tx_queue(vi
->dev
, index
);
1148 if (!sq
->napi
.weight
)
1151 if (__netif_tx_trylock(txq
)) {
1152 free_old_xmit_skbs(sq
);
1153 __netif_tx_unlock(txq
);
1156 if (sq
->vq
->num_free
>= 2 + MAX_SKB_FRAGS
)
1157 netif_tx_wake_queue(txq
);
1160 static int virtnet_poll(struct napi_struct
*napi
, int budget
)
1162 struct receive_queue
*rq
=
1163 container_of(napi
, struct receive_queue
, napi
);
1164 unsigned int received
;
1166 virtnet_poll_cleantx(rq
);
1168 received
= virtnet_receive(rq
, budget
);
1170 /* Out of packets? */
1171 if (received
< budget
)
1172 virtqueue_napi_complete(napi
, rq
->vq
, received
);
1177 static int virtnet_open(struct net_device
*dev
)
1179 struct virtnet_info
*vi
= netdev_priv(dev
);
1182 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1183 if (i
< vi
->curr_queue_pairs
)
1184 /* Make sure we have some buffers: if oom use wq. */
1185 if (!try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
))
1186 schedule_delayed_work(&vi
->refill
, 0);
1187 virtnet_napi_enable(vi
->rq
[i
].vq
, &vi
->rq
[i
].napi
);
1188 virtnet_napi_tx_enable(vi
, vi
->sq
[i
].vq
, &vi
->sq
[i
].napi
);
1194 static int virtnet_poll_tx(struct napi_struct
*napi
, int budget
)
1196 struct send_queue
*sq
= container_of(napi
, struct send_queue
, napi
);
1197 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
1198 struct netdev_queue
*txq
= netdev_get_tx_queue(vi
->dev
, vq2txq(sq
->vq
));
1200 __netif_tx_lock(txq
, raw_smp_processor_id());
1201 free_old_xmit_skbs(sq
);
1202 __netif_tx_unlock(txq
);
1204 virtqueue_napi_complete(napi
, sq
->vq
, 0);
1206 if (sq
->vq
->num_free
>= 2 + MAX_SKB_FRAGS
)
1207 netif_tx_wake_queue(txq
);
1212 static int xmit_skb(struct send_queue
*sq
, struct sk_buff
*skb
)
1214 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
1215 const unsigned char *dest
= ((struct ethhdr
*)skb
->data
)->h_dest
;
1216 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
1218 unsigned hdr_len
= vi
->hdr_len
;
1221 pr_debug("%s: xmit %p %pM\n", vi
->dev
->name
, skb
, dest
);
1223 can_push
= vi
->any_header_sg
&&
1224 !((unsigned long)skb
->data
& (__alignof__(*hdr
) - 1)) &&
1225 !skb_header_cloned(skb
) && skb_headroom(skb
) >= hdr_len
;
1226 /* Even if we can, don't push here yet as this would skew
1227 * csum_start offset below. */
1229 hdr
= (struct virtio_net_hdr_mrg_rxbuf
*)(skb
->data
- hdr_len
);
1231 hdr
= skb_vnet_hdr(skb
);
1233 if (virtio_net_hdr_from_skb(skb
, &hdr
->hdr
,
1234 virtio_is_little_endian(vi
->vdev
), false))
1237 if (vi
->mergeable_rx_bufs
)
1238 hdr
->num_buffers
= 0;
1240 sg_init_table(sq
->sg
, skb_shinfo(skb
)->nr_frags
+ (can_push
? 1 : 2));
1242 __skb_push(skb
, hdr_len
);
1243 num_sg
= skb_to_sgvec(skb
, sq
->sg
, 0, skb
->len
);
1244 if (unlikely(num_sg
< 0))
1246 /* Pull header back to avoid skew in tx bytes calculations. */
1247 __skb_pull(skb
, hdr_len
);
1249 sg_set_buf(sq
->sg
, hdr
, hdr_len
);
1250 num_sg
= skb_to_sgvec(skb
, sq
->sg
+ 1, 0, skb
->len
);
1251 if (unlikely(num_sg
< 0))
1255 return virtqueue_add_outbuf(sq
->vq
, sq
->sg
, num_sg
, skb
, GFP_ATOMIC
);
1258 static netdev_tx_t
start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
1260 struct virtnet_info
*vi
= netdev_priv(dev
);
1261 int qnum
= skb_get_queue_mapping(skb
);
1262 struct send_queue
*sq
= &vi
->sq
[qnum
];
1264 struct netdev_queue
*txq
= netdev_get_tx_queue(dev
, qnum
);
1265 bool kick
= !skb
->xmit_more
;
1266 bool use_napi
= sq
->napi
.weight
;
1268 /* Free up any pending old buffers before queueing new ones. */
1269 free_old_xmit_skbs(sq
);
1271 if (use_napi
&& kick
)
1272 virtqueue_enable_cb_delayed(sq
->vq
);
1274 /* timestamp packet in software */
1275 skb_tx_timestamp(skb
);
1277 /* Try to transmit */
1278 err
= xmit_skb(sq
, skb
);
1280 /* This should not happen! */
1281 if (unlikely(err
)) {
1282 dev
->stats
.tx_fifo_errors
++;
1283 if (net_ratelimit())
1285 "Unexpected TXQ (%d) queue failure: %d\n", qnum
, err
);
1286 dev
->stats
.tx_dropped
++;
1287 dev_kfree_skb_any(skb
);
1288 return NETDEV_TX_OK
;
1291 /* Don't wait up for transmitted skbs to be freed. */
1297 /* If running out of space, stop queue to avoid getting packets that we
1298 * are then unable to transmit.
1299 * An alternative would be to force queuing layer to requeue the skb by
1300 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1301 * returned in a normal path of operation: it means that driver is not
1302 * maintaining the TX queue stop/start state properly, and causes
1303 * the stack to do a non-trivial amount of useless work.
1304 * Since most packets only take 1 or 2 ring slots, stopping the queue
1305 * early means 16 slots are typically wasted.
1307 if (sq
->vq
->num_free
< 2+MAX_SKB_FRAGS
) {
1308 netif_stop_subqueue(dev
, qnum
);
1310 unlikely(!virtqueue_enable_cb_delayed(sq
->vq
))) {
1311 /* More just got used, free them then recheck. */
1312 free_old_xmit_skbs(sq
);
1313 if (sq
->vq
->num_free
>= 2+MAX_SKB_FRAGS
) {
1314 netif_start_subqueue(dev
, qnum
);
1315 virtqueue_disable_cb(sq
->vq
);
1320 if (kick
|| netif_xmit_stopped(txq
))
1321 virtqueue_kick(sq
->vq
);
1323 return NETDEV_TX_OK
;
1327 * Send command via the control virtqueue and check status. Commands
1328 * supported by the hypervisor, as indicated by feature bits, should
1329 * never fail unless improperly formatted.
1331 static bool virtnet_send_command(struct virtnet_info
*vi
, u8
class, u8 cmd
,
1332 struct scatterlist
*out
)
1334 struct scatterlist
*sgs
[4], hdr
, stat
;
1335 unsigned out_num
= 0, tmp
;
1337 /* Caller should know better */
1338 BUG_ON(!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VQ
));
1340 vi
->ctrl_status
= ~0;
1341 vi
->ctrl_hdr
.class = class;
1342 vi
->ctrl_hdr
.cmd
= cmd
;
1344 sg_init_one(&hdr
, &vi
->ctrl_hdr
, sizeof(vi
->ctrl_hdr
));
1345 sgs
[out_num
++] = &hdr
;
1348 sgs
[out_num
++] = out
;
1350 /* Add return status. */
1351 sg_init_one(&stat
, &vi
->ctrl_status
, sizeof(vi
->ctrl_status
));
1352 sgs
[out_num
] = &stat
;
1354 BUG_ON(out_num
+ 1 > ARRAY_SIZE(sgs
));
1355 virtqueue_add_sgs(vi
->cvq
, sgs
, out_num
, 1, vi
, GFP_ATOMIC
);
1357 if (unlikely(!virtqueue_kick(vi
->cvq
)))
1358 return vi
->ctrl_status
== VIRTIO_NET_OK
;
1360 /* Spin for a response, the kick causes an ioport write, trapping
1361 * into the hypervisor, so the request should be handled immediately.
1363 while (!virtqueue_get_buf(vi
->cvq
, &tmp
) &&
1364 !virtqueue_is_broken(vi
->cvq
))
1367 return vi
->ctrl_status
== VIRTIO_NET_OK
;
1370 static int virtnet_set_mac_address(struct net_device
*dev
, void *p
)
1372 struct virtnet_info
*vi
= netdev_priv(dev
);
1373 struct virtio_device
*vdev
= vi
->vdev
;
1375 struct sockaddr
*addr
;
1376 struct scatterlist sg
;
1378 addr
= kmemdup(p
, sizeof(*addr
), GFP_KERNEL
);
1382 ret
= eth_prepare_mac_addr_change(dev
, addr
);
1386 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_MAC_ADDR
)) {
1387 sg_init_one(&sg
, addr
->sa_data
, dev
->addr_len
);
1388 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MAC
,
1389 VIRTIO_NET_CTRL_MAC_ADDR_SET
, &sg
)) {
1390 dev_warn(&vdev
->dev
,
1391 "Failed to set mac address by vq command.\n");
1395 } else if (virtio_has_feature(vdev
, VIRTIO_NET_F_MAC
) &&
1396 !virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
)) {
1399 /* Naturally, this has an atomicity problem. */
1400 for (i
= 0; i
< dev
->addr_len
; i
++)
1401 virtio_cwrite8(vdev
,
1402 offsetof(struct virtio_net_config
, mac
) +
1403 i
, addr
->sa_data
[i
]);
1406 eth_commit_mac_addr_change(dev
, p
);
1414 static void virtnet_stats(struct net_device
*dev
,
1415 struct rtnl_link_stats64
*tot
)
1417 struct virtnet_info
*vi
= netdev_priv(dev
);
1421 for_each_possible_cpu(cpu
) {
1422 struct virtnet_stats
*stats
= per_cpu_ptr(vi
->stats
, cpu
);
1423 u64 tpackets
, tbytes
, rpackets
, rbytes
;
1426 start
= u64_stats_fetch_begin_irq(&stats
->tx_syncp
);
1427 tpackets
= stats
->tx_packets
;
1428 tbytes
= stats
->tx_bytes
;
1429 } while (u64_stats_fetch_retry_irq(&stats
->tx_syncp
, start
));
1432 start
= u64_stats_fetch_begin_irq(&stats
->rx_syncp
);
1433 rpackets
= stats
->rx_packets
;
1434 rbytes
= stats
->rx_bytes
;
1435 } while (u64_stats_fetch_retry_irq(&stats
->rx_syncp
, start
));
1437 tot
->rx_packets
+= rpackets
;
1438 tot
->tx_packets
+= tpackets
;
1439 tot
->rx_bytes
+= rbytes
;
1440 tot
->tx_bytes
+= tbytes
;
1443 tot
->tx_dropped
= dev
->stats
.tx_dropped
;
1444 tot
->tx_fifo_errors
= dev
->stats
.tx_fifo_errors
;
1445 tot
->rx_dropped
= dev
->stats
.rx_dropped
;
1446 tot
->rx_length_errors
= dev
->stats
.rx_length_errors
;
1447 tot
->rx_frame_errors
= dev
->stats
.rx_frame_errors
;
1450 #ifdef CONFIG_NET_POLL_CONTROLLER
1451 static void virtnet_netpoll(struct net_device
*dev
)
1453 struct virtnet_info
*vi
= netdev_priv(dev
);
1456 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++)
1457 napi_schedule(&vi
->rq
[i
].napi
);
1461 static void virtnet_ack_link_announce(struct virtnet_info
*vi
)
1464 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_ANNOUNCE
,
1465 VIRTIO_NET_CTRL_ANNOUNCE_ACK
, NULL
))
1466 dev_warn(&vi
->dev
->dev
, "Failed to ack link announce.\n");
1470 static int _virtnet_set_queues(struct virtnet_info
*vi
, u16 queue_pairs
)
1472 struct scatterlist sg
;
1473 struct net_device
*dev
= vi
->dev
;
1475 if (!vi
->has_cvq
|| !virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_MQ
))
1478 vi
->ctrl_mq
.virtqueue_pairs
= cpu_to_virtio16(vi
->vdev
, queue_pairs
);
1479 sg_init_one(&sg
, &vi
->ctrl_mq
, sizeof(vi
->ctrl_mq
));
1481 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MQ
,
1482 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET
, &sg
)) {
1483 dev_warn(&dev
->dev
, "Fail to set num of queue pairs to %d\n",
1487 vi
->curr_queue_pairs
= queue_pairs
;
1488 /* virtnet_open() will refill when device is going to up. */
1489 if (dev
->flags
& IFF_UP
)
1490 schedule_delayed_work(&vi
->refill
, 0);
1496 static int virtnet_set_queues(struct virtnet_info
*vi
, u16 queue_pairs
)
1501 err
= _virtnet_set_queues(vi
, queue_pairs
);
1506 static int virtnet_close(struct net_device
*dev
)
1508 struct virtnet_info
*vi
= netdev_priv(dev
);
1511 /* Make sure refill_work doesn't re-enable napi! */
1512 cancel_delayed_work_sync(&vi
->refill
);
1514 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1515 napi_disable(&vi
->rq
[i
].napi
);
1516 virtnet_napi_tx_disable(&vi
->sq
[i
].napi
);
1522 static void virtnet_set_rx_mode(struct net_device
*dev
)
1524 struct virtnet_info
*vi
= netdev_priv(dev
);
1525 struct scatterlist sg
[2];
1526 struct virtio_net_ctrl_mac
*mac_data
;
1527 struct netdev_hw_addr
*ha
;
1533 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1534 if (!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_RX
))
1537 vi
->ctrl_promisc
= ((dev
->flags
& IFF_PROMISC
) != 0);
1538 vi
->ctrl_allmulti
= ((dev
->flags
& IFF_ALLMULTI
) != 0);
1540 sg_init_one(sg
, &vi
->ctrl_promisc
, sizeof(vi
->ctrl_promisc
));
1542 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_RX
,
1543 VIRTIO_NET_CTRL_RX_PROMISC
, sg
))
1544 dev_warn(&dev
->dev
, "Failed to %sable promisc mode.\n",
1545 vi
->ctrl_promisc
? "en" : "dis");
1547 sg_init_one(sg
, &vi
->ctrl_allmulti
, sizeof(vi
->ctrl_allmulti
));
1549 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_RX
,
1550 VIRTIO_NET_CTRL_RX_ALLMULTI
, sg
))
1551 dev_warn(&dev
->dev
, "Failed to %sable allmulti mode.\n",
1552 vi
->ctrl_allmulti
? "en" : "dis");
1554 uc_count
= netdev_uc_count(dev
);
1555 mc_count
= netdev_mc_count(dev
);
1556 /* MAC filter - use one buffer for both lists */
1557 buf
= kzalloc(((uc_count
+ mc_count
) * ETH_ALEN
) +
1558 (2 * sizeof(mac_data
->entries
)), GFP_ATOMIC
);
1563 sg_init_table(sg
, 2);
1565 /* Store the unicast list and count in the front of the buffer */
1566 mac_data
->entries
= cpu_to_virtio32(vi
->vdev
, uc_count
);
1568 netdev_for_each_uc_addr(ha
, dev
)
1569 memcpy(&mac_data
->macs
[i
++][0], ha
->addr
, ETH_ALEN
);
1571 sg_set_buf(&sg
[0], mac_data
,
1572 sizeof(mac_data
->entries
) + (uc_count
* ETH_ALEN
));
1574 /* multicast list and count fill the end */
1575 mac_data
= (void *)&mac_data
->macs
[uc_count
][0];
1577 mac_data
->entries
= cpu_to_virtio32(vi
->vdev
, mc_count
);
1579 netdev_for_each_mc_addr(ha
, dev
)
1580 memcpy(&mac_data
->macs
[i
++][0], ha
->addr
, ETH_ALEN
);
1582 sg_set_buf(&sg
[1], mac_data
,
1583 sizeof(mac_data
->entries
) + (mc_count
* ETH_ALEN
));
1585 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MAC
,
1586 VIRTIO_NET_CTRL_MAC_TABLE_SET
, sg
))
1587 dev_warn(&dev
->dev
, "Failed to set MAC filter table.\n");
1592 static int virtnet_vlan_rx_add_vid(struct net_device
*dev
,
1593 __be16 proto
, u16 vid
)
1595 struct virtnet_info
*vi
= netdev_priv(dev
);
1596 struct scatterlist sg
;
1599 sg_init_one(&sg
, &vi
->ctrl_vid
, sizeof(vi
->ctrl_vid
));
1601 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_VLAN
,
1602 VIRTIO_NET_CTRL_VLAN_ADD
, &sg
))
1603 dev_warn(&dev
->dev
, "Failed to add VLAN ID %d.\n", vid
);
1607 static int virtnet_vlan_rx_kill_vid(struct net_device
*dev
,
1608 __be16 proto
, u16 vid
)
1610 struct virtnet_info
*vi
= netdev_priv(dev
);
1611 struct scatterlist sg
;
1614 sg_init_one(&sg
, &vi
->ctrl_vid
, sizeof(vi
->ctrl_vid
));
1616 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_VLAN
,
1617 VIRTIO_NET_CTRL_VLAN_DEL
, &sg
))
1618 dev_warn(&dev
->dev
, "Failed to kill VLAN ID %d.\n", vid
);
1622 static void virtnet_clean_affinity(struct virtnet_info
*vi
, long hcpu
)
1626 if (vi
->affinity_hint_set
) {
1627 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1628 virtqueue_set_affinity(vi
->rq
[i
].vq
, -1);
1629 virtqueue_set_affinity(vi
->sq
[i
].vq
, -1);
1632 vi
->affinity_hint_set
= false;
1636 static void virtnet_set_affinity(struct virtnet_info
*vi
)
1641 /* In multiqueue mode, when the number of cpu is equal to the number of
1642 * queue pairs, we let the queue pairs to be private to one cpu by
1643 * setting the affinity hint to eliminate the contention.
1645 if (vi
->curr_queue_pairs
== 1 ||
1646 vi
->max_queue_pairs
!= num_online_cpus()) {
1647 virtnet_clean_affinity(vi
, -1);
1652 for_each_online_cpu(cpu
) {
1653 virtqueue_set_affinity(vi
->rq
[i
].vq
, cpu
);
1654 virtqueue_set_affinity(vi
->sq
[i
].vq
, cpu
);
1655 netif_set_xps_queue(vi
->dev
, cpumask_of(cpu
), i
);
1659 vi
->affinity_hint_set
= true;
1662 static int virtnet_cpu_online(unsigned int cpu
, struct hlist_node
*node
)
1664 struct virtnet_info
*vi
= hlist_entry_safe(node
, struct virtnet_info
,
1666 virtnet_set_affinity(vi
);
1670 static int virtnet_cpu_dead(unsigned int cpu
, struct hlist_node
*node
)
1672 struct virtnet_info
*vi
= hlist_entry_safe(node
, struct virtnet_info
,
1674 virtnet_set_affinity(vi
);
1678 static int virtnet_cpu_down_prep(unsigned int cpu
, struct hlist_node
*node
)
1680 struct virtnet_info
*vi
= hlist_entry_safe(node
, struct virtnet_info
,
1683 virtnet_clean_affinity(vi
, cpu
);
1687 static enum cpuhp_state virtionet_online
;
1689 static int virtnet_cpu_notif_add(struct virtnet_info
*vi
)
1693 ret
= cpuhp_state_add_instance_nocalls(virtionet_online
, &vi
->node
);
1696 ret
= cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD
,
1700 cpuhp_state_remove_instance_nocalls(virtionet_online
, &vi
->node
);
1704 static void virtnet_cpu_notif_remove(struct virtnet_info
*vi
)
1706 cpuhp_state_remove_instance_nocalls(virtionet_online
, &vi
->node
);
1707 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD
,
1711 static void virtnet_get_ringparam(struct net_device
*dev
,
1712 struct ethtool_ringparam
*ring
)
1714 struct virtnet_info
*vi
= netdev_priv(dev
);
1716 ring
->rx_max_pending
= virtqueue_get_vring_size(vi
->rq
[0].vq
);
1717 ring
->tx_max_pending
= virtqueue_get_vring_size(vi
->sq
[0].vq
);
1718 ring
->rx_pending
= ring
->rx_max_pending
;
1719 ring
->tx_pending
= ring
->tx_max_pending
;
1723 static void virtnet_get_drvinfo(struct net_device
*dev
,
1724 struct ethtool_drvinfo
*info
)
1726 struct virtnet_info
*vi
= netdev_priv(dev
);
1727 struct virtio_device
*vdev
= vi
->vdev
;
1729 strlcpy(info
->driver
, KBUILD_MODNAME
, sizeof(info
->driver
));
1730 strlcpy(info
->version
, VIRTNET_DRIVER_VERSION
, sizeof(info
->version
));
1731 strlcpy(info
->bus_info
, virtio_bus_name(vdev
), sizeof(info
->bus_info
));
1735 /* TODO: Eliminate OOO packets during switching */
1736 static int virtnet_set_channels(struct net_device
*dev
,
1737 struct ethtool_channels
*channels
)
1739 struct virtnet_info
*vi
= netdev_priv(dev
);
1740 u16 queue_pairs
= channels
->combined_count
;
1743 /* We don't support separate rx/tx channels.
1744 * We don't allow setting 'other' channels.
1746 if (channels
->rx_count
|| channels
->tx_count
|| channels
->other_count
)
1749 if (queue_pairs
> vi
->max_queue_pairs
|| queue_pairs
== 0)
1752 /* For now we don't support modifying channels while XDP is loaded
1753 * also when XDP is loaded all RX queues have XDP programs so we only
1754 * need to check a single RX queue.
1756 if (vi
->rq
[0].xdp_prog
)
1760 err
= _virtnet_set_queues(vi
, queue_pairs
);
1762 netif_set_real_num_tx_queues(dev
, queue_pairs
);
1763 netif_set_real_num_rx_queues(dev
, queue_pairs
);
1765 virtnet_set_affinity(vi
);
1772 static void virtnet_get_channels(struct net_device
*dev
,
1773 struct ethtool_channels
*channels
)
1775 struct virtnet_info
*vi
= netdev_priv(dev
);
1777 channels
->combined_count
= vi
->curr_queue_pairs
;
1778 channels
->max_combined
= vi
->max_queue_pairs
;
1779 channels
->max_other
= 0;
1780 channels
->rx_count
= 0;
1781 channels
->tx_count
= 0;
1782 channels
->other_count
= 0;
1785 /* Check if the user is trying to change anything besides speed/duplex */
1787 virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings
*cmd
)
1789 struct ethtool_link_ksettings diff1
= *cmd
;
1790 struct ethtool_link_ksettings diff2
= {};
1792 /* cmd is always set so we need to clear it, validate the port type
1793 * and also without autonegotiation we can ignore advertising
1795 diff1
.base
.speed
= 0;
1796 diff2
.base
.port
= PORT_OTHER
;
1797 ethtool_link_ksettings_zero_link_mode(&diff1
, advertising
);
1798 diff1
.base
.duplex
= 0;
1800 diff1
.base
.link_mode_masks_nwords
= 0;
1802 return !memcmp(&diff1
.base
, &diff2
.base
, sizeof(diff1
.base
)) &&
1803 bitmap_empty(diff1
.link_modes
.supported
,
1804 __ETHTOOL_LINK_MODE_MASK_NBITS
) &&
1805 bitmap_empty(diff1
.link_modes
.advertising
,
1806 __ETHTOOL_LINK_MODE_MASK_NBITS
) &&
1807 bitmap_empty(diff1
.link_modes
.lp_advertising
,
1808 __ETHTOOL_LINK_MODE_MASK_NBITS
);
1811 static int virtnet_set_link_ksettings(struct net_device
*dev
,
1812 const struct ethtool_link_ksettings
*cmd
)
1814 struct virtnet_info
*vi
= netdev_priv(dev
);
1817 speed
= cmd
->base
.speed
;
1818 /* don't allow custom speed and duplex */
1819 if (!ethtool_validate_speed(speed
) ||
1820 !ethtool_validate_duplex(cmd
->base
.duplex
) ||
1821 !virtnet_validate_ethtool_cmd(cmd
))
1824 vi
->duplex
= cmd
->base
.duplex
;
1829 static int virtnet_get_link_ksettings(struct net_device
*dev
,
1830 struct ethtool_link_ksettings
*cmd
)
1832 struct virtnet_info
*vi
= netdev_priv(dev
);
1834 cmd
->base
.speed
= vi
->speed
;
1835 cmd
->base
.duplex
= vi
->duplex
;
1836 cmd
->base
.port
= PORT_OTHER
;
1841 static void virtnet_init_settings(struct net_device
*dev
)
1843 struct virtnet_info
*vi
= netdev_priv(dev
);
1845 vi
->speed
= SPEED_UNKNOWN
;
1846 vi
->duplex
= DUPLEX_UNKNOWN
;
1849 static const struct ethtool_ops virtnet_ethtool_ops
= {
1850 .get_drvinfo
= virtnet_get_drvinfo
,
1851 .get_link
= ethtool_op_get_link
,
1852 .get_ringparam
= virtnet_get_ringparam
,
1853 .set_channels
= virtnet_set_channels
,
1854 .get_channels
= virtnet_get_channels
,
1855 .get_ts_info
= ethtool_op_get_ts_info
,
1856 .get_link_ksettings
= virtnet_get_link_ksettings
,
1857 .set_link_ksettings
= virtnet_set_link_ksettings
,
1860 static void virtnet_freeze_down(struct virtio_device
*vdev
)
1862 struct virtnet_info
*vi
= vdev
->priv
;
1865 /* Make sure no work handler is accessing the device */
1866 flush_work(&vi
->config_work
);
1868 netif_device_detach(vi
->dev
);
1869 netif_tx_disable(vi
->dev
);
1870 cancel_delayed_work_sync(&vi
->refill
);
1872 if (netif_running(vi
->dev
)) {
1873 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1874 napi_disable(&vi
->rq
[i
].napi
);
1875 virtnet_napi_tx_disable(&vi
->sq
[i
].napi
);
1880 static int init_vqs(struct virtnet_info
*vi
);
1882 static int virtnet_restore_up(struct virtio_device
*vdev
)
1884 struct virtnet_info
*vi
= vdev
->priv
;
1891 virtio_device_ready(vdev
);
1893 if (netif_running(vi
->dev
)) {
1894 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++)
1895 if (!try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
))
1896 schedule_delayed_work(&vi
->refill
, 0);
1898 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1899 virtnet_napi_enable(vi
->rq
[i
].vq
, &vi
->rq
[i
].napi
);
1900 virtnet_napi_tx_enable(vi
, vi
->sq
[i
].vq
,
1905 netif_device_attach(vi
->dev
);
1909 static int virtnet_set_guest_offloads(struct virtnet_info
*vi
, u64 offloads
)
1911 struct scatterlist sg
;
1912 vi
->ctrl_offloads
= cpu_to_virtio64(vi
->vdev
, offloads
);
1914 sg_init_one(&sg
, &vi
->ctrl_offloads
, sizeof(vi
->ctrl_offloads
));
1916 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_GUEST_OFFLOADS
,
1917 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET
, &sg
)) {
1918 dev_warn(&vi
->dev
->dev
, "Fail to set guest offload. \n");
1925 static int virtnet_clear_guest_offloads(struct virtnet_info
*vi
)
1929 if (!vi
->guest_offloads
)
1932 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_CSUM
))
1933 offloads
= 1ULL << VIRTIO_NET_F_GUEST_CSUM
;
1935 return virtnet_set_guest_offloads(vi
, offloads
);
1938 static int virtnet_restore_guest_offloads(struct virtnet_info
*vi
)
1940 u64 offloads
= vi
->guest_offloads
;
1942 if (!vi
->guest_offloads
)
1944 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_CSUM
))
1945 offloads
|= 1ULL << VIRTIO_NET_F_GUEST_CSUM
;
1947 return virtnet_set_guest_offloads(vi
, offloads
);
1950 static int virtnet_xdp_set(struct net_device
*dev
, struct bpf_prog
*prog
,
1951 struct netlink_ext_ack
*extack
)
1953 unsigned long int max_sz
= PAGE_SIZE
- sizeof(struct padded_vnet_hdr
);
1954 struct virtnet_info
*vi
= netdev_priv(dev
);
1955 struct bpf_prog
*old_prog
;
1956 u16 xdp_qp
= 0, curr_qp
;
1959 if (!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS
)
1960 && (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_TSO4
) ||
1961 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_TSO6
) ||
1962 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_ECN
) ||
1963 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_GUEST_UFO
))) {
1964 NL_SET_ERR_MSG_MOD(extack
, "Can't set XDP while host is implementing LRO, disable LRO first");
1968 if (vi
->mergeable_rx_bufs
&& !vi
->any_header_sg
) {
1969 NL_SET_ERR_MSG_MOD(extack
, "XDP expects header/data in single page, any_header_sg required");
1973 if (dev
->mtu
> max_sz
) {
1974 NL_SET_ERR_MSG_MOD(extack
, "MTU too large to enable XDP");
1975 netdev_warn(dev
, "XDP requires MTU less than %lu\n", max_sz
);
1979 curr_qp
= vi
->curr_queue_pairs
- vi
->xdp_queue_pairs
;
1981 xdp_qp
= nr_cpu_ids
;
1983 /* XDP requires extra queues for XDP_TX */
1984 if (curr_qp
+ xdp_qp
> vi
->max_queue_pairs
) {
1985 NL_SET_ERR_MSG_MOD(extack
, "Too few free TX rings available");
1986 netdev_warn(dev
, "request %i queues but max is %i\n",
1987 curr_qp
+ xdp_qp
, vi
->max_queue_pairs
);
1992 prog
= bpf_prog_add(prog
, vi
->max_queue_pairs
- 1);
1994 return PTR_ERR(prog
);
1997 /* Make sure NAPI is not using any XDP TX queues for RX. */
1998 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1999 napi_disable(&vi
->rq
[i
].napi
);
2001 netif_set_real_num_rx_queues(dev
, curr_qp
+ xdp_qp
);
2002 err
= _virtnet_set_queues(vi
, curr_qp
+ xdp_qp
);
2005 vi
->xdp_queue_pairs
= xdp_qp
;
2007 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2008 old_prog
= rtnl_dereference(vi
->rq
[i
].xdp_prog
);
2009 rcu_assign_pointer(vi
->rq
[i
].xdp_prog
, prog
);
2012 virtnet_clear_guest_offloads(vi
);
2014 virtnet_restore_guest_offloads(vi
);
2017 bpf_prog_put(old_prog
);
2018 virtnet_napi_enable(vi
->rq
[i
].vq
, &vi
->rq
[i
].napi
);
2024 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
2025 virtnet_napi_enable(vi
->rq
[i
].vq
, &vi
->rq
[i
].napi
);
2027 bpf_prog_sub(prog
, vi
->max_queue_pairs
- 1);
2031 static u32
virtnet_xdp_query(struct net_device
*dev
)
2033 struct virtnet_info
*vi
= netdev_priv(dev
);
2034 const struct bpf_prog
*xdp_prog
;
2037 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2038 xdp_prog
= rtnl_dereference(vi
->rq
[i
].xdp_prog
);
2040 return xdp_prog
->aux
->id
;
2045 static int virtnet_xdp(struct net_device
*dev
, struct netdev_xdp
*xdp
)
2047 switch (xdp
->command
) {
2048 case XDP_SETUP_PROG
:
2049 return virtnet_xdp_set(dev
, xdp
->prog
, xdp
->extack
);
2050 case XDP_QUERY_PROG
:
2051 xdp
->prog_id
= virtnet_xdp_query(dev
);
2052 xdp
->prog_attached
= !!xdp
->prog_id
;
2059 static const struct net_device_ops virtnet_netdev
= {
2060 .ndo_open
= virtnet_open
,
2061 .ndo_stop
= virtnet_close
,
2062 .ndo_start_xmit
= start_xmit
,
2063 .ndo_validate_addr
= eth_validate_addr
,
2064 .ndo_set_mac_address
= virtnet_set_mac_address
,
2065 .ndo_set_rx_mode
= virtnet_set_rx_mode
,
2066 .ndo_get_stats64
= virtnet_stats
,
2067 .ndo_vlan_rx_add_vid
= virtnet_vlan_rx_add_vid
,
2068 .ndo_vlan_rx_kill_vid
= virtnet_vlan_rx_kill_vid
,
2069 #ifdef CONFIG_NET_POLL_CONTROLLER
2070 .ndo_poll_controller
= virtnet_netpoll
,
2072 .ndo_xdp
= virtnet_xdp
,
2073 .ndo_features_check
= passthru_features_check
,
2076 static void virtnet_config_changed_work(struct work_struct
*work
)
2078 struct virtnet_info
*vi
=
2079 container_of(work
, struct virtnet_info
, config_work
);
2082 if (virtio_cread_feature(vi
->vdev
, VIRTIO_NET_F_STATUS
,
2083 struct virtio_net_config
, status
, &v
) < 0)
2086 if (v
& VIRTIO_NET_S_ANNOUNCE
) {
2087 netdev_notify_peers(vi
->dev
);
2088 virtnet_ack_link_announce(vi
);
2091 /* Ignore unknown (future) status bits */
2092 v
&= VIRTIO_NET_S_LINK_UP
;
2094 if (vi
->status
== v
)
2099 if (vi
->status
& VIRTIO_NET_S_LINK_UP
) {
2100 netif_carrier_on(vi
->dev
);
2101 netif_tx_wake_all_queues(vi
->dev
);
2103 netif_carrier_off(vi
->dev
);
2104 netif_tx_stop_all_queues(vi
->dev
);
2108 static void virtnet_config_changed(struct virtio_device
*vdev
)
2110 struct virtnet_info
*vi
= vdev
->priv
;
2112 schedule_work(&vi
->config_work
);
2115 static void virtnet_free_queues(struct virtnet_info
*vi
)
2119 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2120 napi_hash_del(&vi
->rq
[i
].napi
);
2121 netif_napi_del(&vi
->rq
[i
].napi
);
2122 netif_napi_del(&vi
->sq
[i
].napi
);
2125 /* We called napi_hash_del() before netif_napi_del(),
2126 * we need to respect an RCU grace period before freeing vi->rq
2134 static void _free_receive_bufs(struct virtnet_info
*vi
)
2136 struct bpf_prog
*old_prog
;
2139 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2140 while (vi
->rq
[i
].pages
)
2141 __free_pages(get_a_page(&vi
->rq
[i
], GFP_KERNEL
), 0);
2143 old_prog
= rtnl_dereference(vi
->rq
[i
].xdp_prog
);
2144 RCU_INIT_POINTER(vi
->rq
[i
].xdp_prog
, NULL
);
2146 bpf_prog_put(old_prog
);
2150 static void free_receive_bufs(struct virtnet_info
*vi
)
2153 _free_receive_bufs(vi
);
2157 static void free_receive_page_frags(struct virtnet_info
*vi
)
2160 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
2161 if (vi
->rq
[i
].alloc_frag
.page
)
2162 put_page(vi
->rq
[i
].alloc_frag
.page
);
2165 static bool is_xdp_raw_buffer_queue(struct virtnet_info
*vi
, int q
)
2167 if (q
< (vi
->curr_queue_pairs
- vi
->xdp_queue_pairs
))
2169 else if (q
< vi
->curr_queue_pairs
)
2175 static void free_unused_bufs(struct virtnet_info
*vi
)
2180 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2181 struct virtqueue
*vq
= vi
->sq
[i
].vq
;
2182 while ((buf
= virtqueue_detach_unused_buf(vq
)) != NULL
) {
2183 if (!is_xdp_raw_buffer_queue(vi
, i
))
2186 put_page(virt_to_head_page(buf
));
2190 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2191 struct virtqueue
*vq
= vi
->rq
[i
].vq
;
2193 while ((buf
= virtqueue_detach_unused_buf(vq
)) != NULL
) {
2194 if (vi
->mergeable_rx_bufs
) {
2195 put_page(virt_to_head_page(buf
));
2196 } else if (vi
->big_packets
) {
2197 give_pages(&vi
->rq
[i
], buf
);
2199 put_page(virt_to_head_page(buf
));
2205 static void virtnet_del_vqs(struct virtnet_info
*vi
)
2207 struct virtio_device
*vdev
= vi
->vdev
;
2209 virtnet_clean_affinity(vi
, -1);
2211 vdev
->config
->del_vqs(vdev
);
2213 virtnet_free_queues(vi
);
2216 /* How large should a single buffer be so a queue full of these can fit at
2217 * least one full packet?
2218 * Logic below assumes the mergeable buffer header is used.
2220 static unsigned int mergeable_min_buf_len(struct virtnet_info
*vi
, struct virtqueue
*vq
)
2222 const unsigned int hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
2223 unsigned int rq_size
= virtqueue_get_vring_size(vq
);
2224 unsigned int packet_len
= vi
->big_packets
? IP_MAX_MTU
: vi
->dev
->max_mtu
;
2225 unsigned int buf_len
= hdr_len
+ ETH_HLEN
+ VLAN_HLEN
+ packet_len
;
2226 unsigned int min_buf_len
= DIV_ROUND_UP(buf_len
, rq_size
);
2228 return max(max(min_buf_len
, hdr_len
) - hdr_len
,
2229 (unsigned int)GOOD_PACKET_LEN
);
2232 static int virtnet_find_vqs(struct virtnet_info
*vi
)
2234 vq_callback_t
**callbacks
;
2235 struct virtqueue
**vqs
;
2241 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2242 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2243 * possible control vq.
2245 total_vqs
= vi
->max_queue_pairs
* 2 +
2246 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VQ
);
2248 /* Allocate space for find_vqs parameters */
2249 vqs
= kzalloc(total_vqs
* sizeof(*vqs
), GFP_KERNEL
);
2252 callbacks
= kmalloc(total_vqs
* sizeof(*callbacks
), GFP_KERNEL
);
2255 names
= kmalloc(total_vqs
* sizeof(*names
), GFP_KERNEL
);
2258 if (!vi
->big_packets
|| vi
->mergeable_rx_bufs
) {
2259 ctx
= kzalloc(total_vqs
* sizeof(*ctx
), GFP_KERNEL
);
2266 /* Parameters for control virtqueue, if any */
2268 callbacks
[total_vqs
- 1] = NULL
;
2269 names
[total_vqs
- 1] = "control";
2272 /* Allocate/initialize parameters for send/receive virtqueues */
2273 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2274 callbacks
[rxq2vq(i
)] = skb_recv_done
;
2275 callbacks
[txq2vq(i
)] = skb_xmit_done
;
2276 sprintf(vi
->rq
[i
].name
, "input.%d", i
);
2277 sprintf(vi
->sq
[i
].name
, "output.%d", i
);
2278 names
[rxq2vq(i
)] = vi
->rq
[i
].name
;
2279 names
[txq2vq(i
)] = vi
->sq
[i
].name
;
2281 ctx
[rxq2vq(i
)] = true;
2284 ret
= vi
->vdev
->config
->find_vqs(vi
->vdev
, total_vqs
, vqs
, callbacks
,
2290 vi
->cvq
= vqs
[total_vqs
- 1];
2291 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VLAN
))
2292 vi
->dev
->features
|= NETIF_F_HW_VLAN_CTAG_FILTER
;
2295 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2296 vi
->rq
[i
].vq
= vqs
[rxq2vq(i
)];
2297 vi
->rq
[i
].min_buf_len
= mergeable_min_buf_len(vi
, vi
->rq
[i
].vq
);
2298 vi
->sq
[i
].vq
= vqs
[txq2vq(i
)];
2320 static int virtnet_alloc_queues(struct virtnet_info
*vi
)
2324 vi
->sq
= kzalloc(sizeof(*vi
->sq
) * vi
->max_queue_pairs
, GFP_KERNEL
);
2327 vi
->rq
= kzalloc(sizeof(*vi
->rq
) * vi
->max_queue_pairs
, GFP_KERNEL
);
2331 INIT_DELAYED_WORK(&vi
->refill
, refill_work
);
2332 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
2333 vi
->rq
[i
].pages
= NULL
;
2334 netif_napi_add(vi
->dev
, &vi
->rq
[i
].napi
, virtnet_poll
,
2336 netif_tx_napi_add(vi
->dev
, &vi
->sq
[i
].napi
, virtnet_poll_tx
,
2337 napi_tx
? napi_weight
: 0);
2339 sg_init_table(vi
->rq
[i
].sg
, ARRAY_SIZE(vi
->rq
[i
].sg
));
2340 ewma_pkt_len_init(&vi
->rq
[i
].mrg_avg_pkt_len
);
2341 sg_init_table(vi
->sq
[i
].sg
, ARRAY_SIZE(vi
->sq
[i
].sg
));
2352 static int init_vqs(struct virtnet_info
*vi
)
2356 /* Allocate send & receive queues */
2357 ret
= virtnet_alloc_queues(vi
);
2361 ret
= virtnet_find_vqs(vi
);
2366 virtnet_set_affinity(vi
);
2372 virtnet_free_queues(vi
);
2378 static ssize_t
mergeable_rx_buffer_size_show(struct netdev_rx_queue
*queue
,
2381 struct virtnet_info
*vi
= netdev_priv(queue
->dev
);
2382 unsigned int queue_index
= get_netdev_rx_queue_index(queue
);
2383 struct ewma_pkt_len
*avg
;
2385 BUG_ON(queue_index
>= vi
->max_queue_pairs
);
2386 avg
= &vi
->rq
[queue_index
].mrg_avg_pkt_len
;
2387 return sprintf(buf
, "%u\n",
2388 get_mergeable_buf_len(&vi
->rq
[queue_index
], avg
));
2391 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute
=
2392 __ATTR_RO(mergeable_rx_buffer_size
);
2394 static struct attribute
*virtio_net_mrg_rx_attrs
[] = {
2395 &mergeable_rx_buffer_size_attribute
.attr
,
2399 static const struct attribute_group virtio_net_mrg_rx_group
= {
2400 .name
= "virtio_net",
2401 .attrs
= virtio_net_mrg_rx_attrs
2405 static bool virtnet_fail_on_feature(struct virtio_device
*vdev
,
2407 const char *fname
, const char *dname
)
2409 if (!virtio_has_feature(vdev
, fbit
))
2412 dev_err(&vdev
->dev
, "device advertises feature %s but not %s",
2418 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2419 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2421 static bool virtnet_validate_features(struct virtio_device
*vdev
)
2423 if (!virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
) &&
2424 (VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_RX
,
2425 "VIRTIO_NET_F_CTRL_VQ") ||
2426 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_VLAN
,
2427 "VIRTIO_NET_F_CTRL_VQ") ||
2428 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_GUEST_ANNOUNCE
,
2429 "VIRTIO_NET_F_CTRL_VQ") ||
2430 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_MQ
, "VIRTIO_NET_F_CTRL_VQ") ||
2431 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_MAC_ADDR
,
2432 "VIRTIO_NET_F_CTRL_VQ"))) {
2439 #define MIN_MTU ETH_MIN_MTU
2440 #define MAX_MTU ETH_MAX_MTU
2442 static int virtnet_validate(struct virtio_device
*vdev
)
2444 if (!vdev
->config
->get
) {
2445 dev_err(&vdev
->dev
, "%s failure: config access disabled\n",
2450 if (!virtnet_validate_features(vdev
))
2453 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MTU
)) {
2454 int mtu
= virtio_cread16(vdev
,
2455 offsetof(struct virtio_net_config
,
2458 __virtio_clear_bit(vdev
, VIRTIO_NET_F_MTU
);
2464 static int virtnet_probe(struct virtio_device
*vdev
)
2467 struct net_device
*dev
;
2468 struct virtnet_info
*vi
;
2469 u16 max_queue_pairs
;
2472 /* Find if host supports multiqueue virtio_net device */
2473 err
= virtio_cread_feature(vdev
, VIRTIO_NET_F_MQ
,
2474 struct virtio_net_config
,
2475 max_virtqueue_pairs
, &max_queue_pairs
);
2477 /* We need at least 2 queue's */
2478 if (err
|| max_queue_pairs
< VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN
||
2479 max_queue_pairs
> VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX
||
2480 !virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
))
2481 max_queue_pairs
= 1;
2483 /* Allocate ourselves a network device with room for our info */
2484 dev
= alloc_etherdev_mq(sizeof(struct virtnet_info
), max_queue_pairs
);
2488 /* Set up network device as normal. */
2489 dev
->priv_flags
|= IFF_UNICAST_FLT
| IFF_LIVE_ADDR_CHANGE
;
2490 dev
->netdev_ops
= &virtnet_netdev
;
2491 dev
->features
= NETIF_F_HIGHDMA
;
2493 dev
->ethtool_ops
= &virtnet_ethtool_ops
;
2494 SET_NETDEV_DEV(dev
, &vdev
->dev
);
2496 /* Do we support "hardware" checksums? */
2497 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CSUM
)) {
2498 /* This opens up the world of extra features. */
2499 dev
->hw_features
|= NETIF_F_HW_CSUM
| NETIF_F_SG
;
2501 dev
->features
|= NETIF_F_HW_CSUM
| NETIF_F_SG
;
2503 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GSO
)) {
2504 dev
->hw_features
|= NETIF_F_TSO
2505 | NETIF_F_TSO_ECN
| NETIF_F_TSO6
;
2507 /* Individual feature bits: what can host handle? */
2508 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_TSO4
))
2509 dev
->hw_features
|= NETIF_F_TSO
;
2510 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_TSO6
))
2511 dev
->hw_features
|= NETIF_F_TSO6
;
2512 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_ECN
))
2513 dev
->hw_features
|= NETIF_F_TSO_ECN
;
2515 dev
->features
|= NETIF_F_GSO_ROBUST
;
2518 dev
->features
|= dev
->hw_features
& NETIF_F_ALL_TSO
;
2519 /* (!csum && gso) case will be fixed by register_netdev() */
2521 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_CSUM
))
2522 dev
->features
|= NETIF_F_RXCSUM
;
2524 dev
->vlan_features
= dev
->features
;
2526 /* MTU range: 68 - 65535 */
2527 dev
->min_mtu
= MIN_MTU
;
2528 dev
->max_mtu
= MAX_MTU
;
2530 /* Configuration may specify what MAC to use. Otherwise random. */
2531 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MAC
))
2532 virtio_cread_bytes(vdev
,
2533 offsetof(struct virtio_net_config
, mac
),
2534 dev
->dev_addr
, dev
->addr_len
);
2536 eth_hw_addr_random(dev
);
2538 /* Set up our device-specific information */
2539 vi
= netdev_priv(dev
);
2543 vi
->stats
= alloc_percpu(struct virtnet_stats
);
2545 if (vi
->stats
== NULL
)
2548 for_each_possible_cpu(i
) {
2549 struct virtnet_stats
*virtnet_stats
;
2550 virtnet_stats
= per_cpu_ptr(vi
->stats
, i
);
2551 u64_stats_init(&virtnet_stats
->tx_syncp
);
2552 u64_stats_init(&virtnet_stats
->rx_syncp
);
2555 INIT_WORK(&vi
->config_work
, virtnet_config_changed_work
);
2557 /* If we can receive ANY GSO packets, we must allocate large ones. */
2558 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_TSO4
) ||
2559 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_TSO6
) ||
2560 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_ECN
) ||
2561 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_UFO
))
2562 vi
->big_packets
= true;
2564 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MRG_RXBUF
))
2565 vi
->mergeable_rx_bufs
= true;
2567 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MRG_RXBUF
) ||
2568 virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
))
2569 vi
->hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
2571 vi
->hdr_len
= sizeof(struct virtio_net_hdr
);
2573 if (virtio_has_feature(vdev
, VIRTIO_F_ANY_LAYOUT
) ||
2574 virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
))
2575 vi
->any_header_sg
= true;
2577 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
))
2580 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MTU
)) {
2581 mtu
= virtio_cread16(vdev
,
2582 offsetof(struct virtio_net_config
,
2584 if (mtu
< dev
->min_mtu
) {
2585 /* Should never trigger: MTU was previously validated
2586 * in virtnet_validate.
2588 dev_err(&vdev
->dev
, "device MTU appears to have changed "
2589 "it is now %d < %d", mtu
, dev
->min_mtu
);
2596 /* TODO: size buffers correctly in this case. */
2597 if (dev
->mtu
> ETH_DATA_LEN
)
2598 vi
->big_packets
= true;
2601 if (vi
->any_header_sg
)
2602 dev
->needed_headroom
= vi
->hdr_len
;
2604 /* Enable multiqueue by default */
2605 if (num_online_cpus() >= max_queue_pairs
)
2606 vi
->curr_queue_pairs
= max_queue_pairs
;
2608 vi
->curr_queue_pairs
= num_online_cpus();
2609 vi
->max_queue_pairs
= max_queue_pairs
;
2611 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
2617 if (vi
->mergeable_rx_bufs
)
2618 dev
->sysfs_rx_queue_group
= &virtio_net_mrg_rx_group
;
2620 netif_set_real_num_tx_queues(dev
, vi
->curr_queue_pairs
);
2621 netif_set_real_num_rx_queues(dev
, vi
->curr_queue_pairs
);
2623 virtnet_init_settings(dev
);
2625 err
= register_netdev(dev
);
2627 pr_debug("virtio_net: registering device failed\n");
2631 virtio_device_ready(vdev
);
2633 err
= virtnet_cpu_notif_add(vi
);
2635 pr_debug("virtio_net: registering cpu notifier failed\n");
2636 goto free_unregister_netdev
;
2639 virtnet_set_queues(vi
, vi
->curr_queue_pairs
);
2641 /* Assume link up if device can't report link status,
2642 otherwise get link status from config. */
2643 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_STATUS
)) {
2644 netif_carrier_off(dev
);
2645 schedule_work(&vi
->config_work
);
2647 vi
->status
= VIRTIO_NET_S_LINK_UP
;
2648 netif_carrier_on(dev
);
2651 for (i
= 0; i
< ARRAY_SIZE(guest_offloads
); i
++)
2652 if (virtio_has_feature(vi
->vdev
, guest_offloads
[i
]))
2653 set_bit(guest_offloads
[i
], &vi
->guest_offloads
);
2655 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
2656 dev
->name
, max_queue_pairs
);
2660 free_unregister_netdev
:
2661 vi
->vdev
->config
->reset(vdev
);
2663 unregister_netdev(dev
);
2665 cancel_delayed_work_sync(&vi
->refill
);
2666 free_receive_page_frags(vi
);
2667 virtnet_del_vqs(vi
);
2669 free_percpu(vi
->stats
);
2675 static void remove_vq_common(struct virtnet_info
*vi
)
2677 vi
->vdev
->config
->reset(vi
->vdev
);
2679 /* Free unused buffers in both send and recv, if any. */
2680 free_unused_bufs(vi
);
2682 free_receive_bufs(vi
);
2684 free_receive_page_frags(vi
);
2686 virtnet_del_vqs(vi
);
2689 static void virtnet_remove(struct virtio_device
*vdev
)
2691 struct virtnet_info
*vi
= vdev
->priv
;
2693 virtnet_cpu_notif_remove(vi
);
2695 /* Make sure no work handler is accessing the device. */
2696 flush_work(&vi
->config_work
);
2698 unregister_netdev(vi
->dev
);
2700 remove_vq_common(vi
);
2702 free_percpu(vi
->stats
);
2703 free_netdev(vi
->dev
);
2706 static __maybe_unused
int virtnet_freeze(struct virtio_device
*vdev
)
2708 struct virtnet_info
*vi
= vdev
->priv
;
2710 virtnet_cpu_notif_remove(vi
);
2711 virtnet_freeze_down(vdev
);
2712 remove_vq_common(vi
);
2717 static __maybe_unused
int virtnet_restore(struct virtio_device
*vdev
)
2719 struct virtnet_info
*vi
= vdev
->priv
;
2722 err
= virtnet_restore_up(vdev
);
2725 virtnet_set_queues(vi
, vi
->curr_queue_pairs
);
2727 err
= virtnet_cpu_notif_add(vi
);
2734 static struct virtio_device_id id_table
[] = {
2735 { VIRTIO_ID_NET
, VIRTIO_DEV_ANY_ID
},
2739 #define VIRTNET_FEATURES \
2740 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
2742 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
2743 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
2744 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
2745 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
2746 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
2747 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
2748 VIRTIO_NET_F_CTRL_MAC_ADDR, \
2749 VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS
2751 static unsigned int features
[] = {
2755 static unsigned int features_legacy
[] = {
2758 VIRTIO_F_ANY_LAYOUT
,
2761 static struct virtio_driver virtio_net_driver
= {
2762 .feature_table
= features
,
2763 .feature_table_size
= ARRAY_SIZE(features
),
2764 .feature_table_legacy
= features_legacy
,
2765 .feature_table_size_legacy
= ARRAY_SIZE(features_legacy
),
2766 .driver
.name
= KBUILD_MODNAME
,
2767 .driver
.owner
= THIS_MODULE
,
2768 .id_table
= id_table
,
2769 .validate
= virtnet_validate
,
2770 .probe
= virtnet_probe
,
2771 .remove
= virtnet_remove
,
2772 .config_changed
= virtnet_config_changed
,
2773 #ifdef CONFIG_PM_SLEEP
2774 .freeze
= virtnet_freeze
,
2775 .restore
= virtnet_restore
,
2779 static __init
int virtio_net_driver_init(void)
2783 ret
= cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN
, "virtio/net:online",
2785 virtnet_cpu_down_prep
);
2788 virtionet_online
= ret
;
2789 ret
= cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD
, "virtio/net:dead",
2790 NULL
, virtnet_cpu_dead
);
2794 ret
= register_virtio_driver(&virtio_net_driver
);
2799 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD
);
2801 cpuhp_remove_multi_state(virtionet_online
);
2805 module_init(virtio_net_driver_init
);
2807 static __exit
void virtio_net_driver_exit(void)
2809 unregister_virtio_driver(&virtio_net_driver
);
2810 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD
);
2811 cpuhp_remove_multi_state(virtionet_online
);
2813 module_exit(virtio_net_driver_exit
);
2815 MODULE_DEVICE_TABLE(virtio
, id_table
);
2816 MODULE_DESCRIPTION("Virtio network driver");
2817 MODULE_LICENSE("GPL");