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/scatterlist.h>
26 #include <linux/if_vlan.h>
27 #include <linux/slab.h>
28 #include <linux/cpu.h>
29 #include <linux/average.h>
30 #include <net/busy_poll.h>
32 static int napi_weight
= NAPI_POLL_WEIGHT
;
33 module_param(napi_weight
, int, 0444);
35 static bool csum
= true, gso
= true;
36 module_param(csum
, bool, 0444);
37 module_param(gso
, bool, 0444);
39 /* FIXME: MTU in config. */
40 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
41 #define GOOD_COPY_LEN 128
43 /* RX packet size EWMA. The average packet size is used to determine the packet
44 * buffer size when refilling RX rings. As the entire RX ring may be refilled
45 * at once, the weight is chosen so that the EWMA will be insensitive to short-
46 * term, transient changes in packet size.
48 DECLARE_EWMA(pkt_len
, 1, 64)
50 /* Minimum alignment for mergeable packet buffers. */
51 #define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, 256)
53 #define VIRTNET_DRIVER_VERSION "1.0.0"
55 struct virtnet_stats
{
56 struct u64_stats_sync tx_syncp
;
57 struct u64_stats_sync rx_syncp
;
65 /* Internal representation of a send virtqueue */
67 /* Virtqueue associated with this send _queue */
70 /* TX: fragments + linear part + virtio header */
71 struct scatterlist sg
[MAX_SKB_FRAGS
+ 2];
73 /* Name of the send queue: output.$index */
77 /* Internal representation of a receive virtqueue */
78 struct receive_queue
{
79 /* Virtqueue associated with this receive_queue */
82 struct napi_struct napi
;
84 /* Chain pages by the private ptr. */
87 /* Average packet length for mergeable receive buffers. */
88 struct ewma_pkt_len mrg_avg_pkt_len
;
90 /* Page frag for packet buffer allocation. */
91 struct page_frag alloc_frag
;
93 /* RX: fragments + linear part + virtio header */
94 struct scatterlist sg
[MAX_SKB_FRAGS
+ 2];
96 /* Name of this receive queue: input.$index */
100 struct virtnet_info
{
101 struct virtio_device
*vdev
;
102 struct virtqueue
*cvq
;
103 struct net_device
*dev
;
104 struct send_queue
*sq
;
105 struct receive_queue
*rq
;
108 /* Max # of queue pairs supported by the device */
111 /* # of queue pairs currently used by the driver */
112 u16 curr_queue_pairs
;
114 /* I like... big packets and I cannot lie! */
117 /* Host will merge rx buffers for big packets (shake it! shake it!) */
118 bool mergeable_rx_bufs
;
120 /* Has control virtqueue */
123 /* Host can handle any s/g split between our header and packet data */
126 /* Packet virtio header size */
129 /* Active statistics */
130 struct virtnet_stats __percpu
*stats
;
132 /* Work struct for refilling if we run low on memory. */
133 struct delayed_work refill
;
135 /* Work struct for config space updates */
136 struct work_struct config_work
;
138 /* Does the affinity hint is set for virtqueues? */
139 bool affinity_hint_set
;
141 /* CPU hot plug notifier */
142 struct notifier_block nb
;
145 struct padded_vnet_hdr
{
146 struct virtio_net_hdr_mrg_rxbuf hdr
;
148 * hdr is in a separate sg buffer, and data sg buffer shares same page
149 * with this header sg. This padding makes next sg 16 byte aligned
155 /* Converting between virtqueue no. and kernel tx/rx queue no.
156 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
158 static int vq2txq(struct virtqueue
*vq
)
160 return (vq
->index
- 1) / 2;
163 static int txq2vq(int txq
)
168 static int vq2rxq(struct virtqueue
*vq
)
170 return vq
->index
/ 2;
173 static int rxq2vq(int rxq
)
178 static inline struct virtio_net_hdr_mrg_rxbuf
*skb_vnet_hdr(struct sk_buff
*skb
)
180 return (struct virtio_net_hdr_mrg_rxbuf
*)skb
->cb
;
184 * private is used to chain pages for big packets, put the whole
185 * most recent used list in the beginning for reuse
187 static void give_pages(struct receive_queue
*rq
, struct page
*page
)
191 /* Find end of list, sew whole thing into vi->rq.pages. */
192 for (end
= page
; end
->private; end
= (struct page
*)end
->private);
193 end
->private = (unsigned long)rq
->pages
;
197 static struct page
*get_a_page(struct receive_queue
*rq
, gfp_t gfp_mask
)
199 struct page
*p
= rq
->pages
;
202 rq
->pages
= (struct page
*)p
->private;
203 /* clear private here, it is used to chain pages */
206 p
= alloc_page(gfp_mask
);
210 static void skb_xmit_done(struct virtqueue
*vq
)
212 struct virtnet_info
*vi
= vq
->vdev
->priv
;
214 /* Suppress further interrupts. */
215 virtqueue_disable_cb(vq
);
217 /* We were probably waiting for more output buffers. */
218 netif_wake_subqueue(vi
->dev
, vq2txq(vq
));
221 static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx
)
223 unsigned int truesize
= mrg_ctx
& (MERGEABLE_BUFFER_ALIGN
- 1);
224 return (truesize
+ 1) * MERGEABLE_BUFFER_ALIGN
;
227 static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx
)
229 return (void *)(mrg_ctx
& -MERGEABLE_BUFFER_ALIGN
);
233 static unsigned long mergeable_buf_to_ctx(void *buf
, unsigned int truesize
)
235 unsigned int size
= truesize
/ MERGEABLE_BUFFER_ALIGN
;
236 return (unsigned long)buf
| (size
- 1);
239 /* Called from bottom half context */
240 static struct sk_buff
*page_to_skb(struct virtnet_info
*vi
,
241 struct receive_queue
*rq
,
242 struct page
*page
, unsigned int offset
,
243 unsigned int len
, unsigned int truesize
)
246 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
247 unsigned int copy
, hdr_len
, hdr_padded_len
;
250 p
= page_address(page
) + offset
;
252 /* copy small packet so we can reuse these pages for small data */
253 skb
= netdev_alloc_skb_ip_align(vi
->dev
, GOOD_COPY_LEN
);
257 hdr
= skb_vnet_hdr(skb
);
259 hdr_len
= vi
->hdr_len
;
260 if (vi
->mergeable_rx_bufs
)
261 hdr_padded_len
= sizeof *hdr
;
263 hdr_padded_len
= sizeof(struct padded_vnet_hdr
);
265 memcpy(hdr
, p
, hdr_len
);
268 offset
+= hdr_padded_len
;
272 if (copy
> skb_tailroom(skb
))
273 copy
= skb_tailroom(skb
);
274 memcpy(skb_put(skb
, copy
), p
, copy
);
279 if (vi
->mergeable_rx_bufs
) {
281 skb_add_rx_frag(skb
, 0, page
, offset
, len
, truesize
);
288 * Verify that we can indeed put this data into a skb.
289 * This is here to handle cases when the device erroneously
290 * tries to receive more than is possible. This is usually
291 * the case of a broken device.
293 if (unlikely(len
> MAX_SKB_FRAGS
* PAGE_SIZE
)) {
294 net_dbg_ratelimited("%s: too much data\n", skb
->dev
->name
);
298 BUG_ON(offset
>= PAGE_SIZE
);
300 unsigned int frag_size
= min((unsigned)PAGE_SIZE
- offset
, len
);
301 skb_add_rx_frag(skb
, skb_shinfo(skb
)->nr_frags
, page
, offset
,
302 frag_size
, truesize
);
304 page
= (struct page
*)page
->private;
309 give_pages(rq
, page
);
314 static struct sk_buff
*receive_small(struct virtnet_info
*vi
, void *buf
, unsigned int len
)
316 struct sk_buff
* skb
= buf
;
324 static struct sk_buff
*receive_big(struct net_device
*dev
,
325 struct virtnet_info
*vi
,
326 struct receive_queue
*rq
,
330 struct page
*page
= buf
;
331 struct sk_buff
*skb
= page_to_skb(vi
, rq
, page
, 0, len
, PAGE_SIZE
);
339 dev
->stats
.rx_dropped
++;
340 give_pages(rq
, page
);
344 static struct sk_buff
*receive_mergeable(struct net_device
*dev
,
345 struct virtnet_info
*vi
,
346 struct receive_queue
*rq
,
350 void *buf
= mergeable_ctx_to_buf_address(ctx
);
351 struct virtio_net_hdr_mrg_rxbuf
*hdr
= buf
;
352 u16 num_buf
= virtio16_to_cpu(vi
->vdev
, hdr
->num_buffers
);
353 struct page
*page
= virt_to_head_page(buf
);
354 int offset
= buf
- page_address(page
);
355 unsigned int truesize
= max(len
, mergeable_ctx_to_buf_truesize(ctx
));
357 struct sk_buff
*head_skb
= page_to_skb(vi
, rq
, page
, offset
, len
,
359 struct sk_buff
*curr_skb
= head_skb
;
361 if (unlikely(!curr_skb
))
366 ctx
= (unsigned long)virtqueue_get_buf(rq
->vq
, &len
);
367 if (unlikely(!ctx
)) {
368 pr_debug("%s: rx error: %d buffers out of %d missing\n",
370 virtio16_to_cpu(vi
->vdev
,
372 dev
->stats
.rx_length_errors
++;
376 buf
= mergeable_ctx_to_buf_address(ctx
);
377 page
= virt_to_head_page(buf
);
379 num_skb_frags
= skb_shinfo(curr_skb
)->nr_frags
;
380 if (unlikely(num_skb_frags
== MAX_SKB_FRAGS
)) {
381 struct sk_buff
*nskb
= alloc_skb(0, GFP_ATOMIC
);
385 if (curr_skb
== head_skb
)
386 skb_shinfo(curr_skb
)->frag_list
= nskb
;
388 curr_skb
->next
= nskb
;
390 head_skb
->truesize
+= nskb
->truesize
;
393 truesize
= max(len
, mergeable_ctx_to_buf_truesize(ctx
));
394 if (curr_skb
!= head_skb
) {
395 head_skb
->data_len
+= len
;
396 head_skb
->len
+= len
;
397 head_skb
->truesize
+= truesize
;
399 offset
= buf
- page_address(page
);
400 if (skb_can_coalesce(curr_skb
, num_skb_frags
, page
, offset
)) {
402 skb_coalesce_rx_frag(curr_skb
, num_skb_frags
- 1,
405 skb_add_rx_frag(curr_skb
, num_skb_frags
, page
,
406 offset
, len
, truesize
);
410 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, head_skb
->len
);
416 ctx
= (unsigned long)virtqueue_get_buf(rq
->vq
, &len
);
417 if (unlikely(!ctx
)) {
418 pr_debug("%s: rx error: %d buffers missing\n",
420 dev
->stats
.rx_length_errors
++;
423 page
= virt_to_head_page(mergeable_ctx_to_buf_address(ctx
));
427 dev
->stats
.rx_dropped
++;
428 dev_kfree_skb(head_skb
);
432 static void receive_buf(struct virtnet_info
*vi
, struct receive_queue
*rq
,
433 void *buf
, unsigned int len
)
435 struct net_device
*dev
= vi
->dev
;
436 struct virtnet_stats
*stats
= this_cpu_ptr(vi
->stats
);
438 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
440 if (unlikely(len
< vi
->hdr_len
+ ETH_HLEN
)) {
441 pr_debug("%s: short packet %i\n", dev
->name
, len
);
442 dev
->stats
.rx_length_errors
++;
443 if (vi
->mergeable_rx_bufs
) {
444 unsigned long ctx
= (unsigned long)buf
;
445 void *base
= mergeable_ctx_to_buf_address(ctx
);
446 put_page(virt_to_head_page(base
));
447 } else if (vi
->big_packets
) {
455 if (vi
->mergeable_rx_bufs
)
456 skb
= receive_mergeable(dev
, vi
, rq
, (unsigned long)buf
, len
);
457 else if (vi
->big_packets
)
458 skb
= receive_big(dev
, vi
, rq
, buf
, len
);
460 skb
= receive_small(vi
, buf
, len
);
465 hdr
= skb_vnet_hdr(skb
);
467 u64_stats_update_begin(&stats
->rx_syncp
);
468 stats
->rx_bytes
+= skb
->len
;
470 u64_stats_update_end(&stats
->rx_syncp
);
472 if (hdr
->hdr
.flags
& VIRTIO_NET_HDR_F_NEEDS_CSUM
) {
473 pr_debug("Needs csum!\n");
474 if (!skb_partial_csum_set(skb
,
475 virtio16_to_cpu(vi
->vdev
, hdr
->hdr
.csum_start
),
476 virtio16_to_cpu(vi
->vdev
, hdr
->hdr
.csum_offset
)))
478 } else if (hdr
->hdr
.flags
& VIRTIO_NET_HDR_F_DATA_VALID
) {
479 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
482 skb
->protocol
= eth_type_trans(skb
, dev
);
483 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
484 ntohs(skb
->protocol
), skb
->len
, skb
->pkt_type
);
486 if (hdr
->hdr
.gso_type
!= VIRTIO_NET_HDR_GSO_NONE
) {
488 switch (hdr
->hdr
.gso_type
& ~VIRTIO_NET_HDR_GSO_ECN
) {
489 case VIRTIO_NET_HDR_GSO_TCPV4
:
490 skb_shinfo(skb
)->gso_type
= SKB_GSO_TCPV4
;
492 case VIRTIO_NET_HDR_GSO_UDP
:
493 skb_shinfo(skb
)->gso_type
= SKB_GSO_UDP
;
495 case VIRTIO_NET_HDR_GSO_TCPV6
:
496 skb_shinfo(skb
)->gso_type
= SKB_GSO_TCPV6
;
499 net_warn_ratelimited("%s: bad gso type %u.\n",
500 dev
->name
, hdr
->hdr
.gso_type
);
504 if (hdr
->hdr
.gso_type
& VIRTIO_NET_HDR_GSO_ECN
)
505 skb_shinfo(skb
)->gso_type
|= SKB_GSO_TCP_ECN
;
507 skb_shinfo(skb
)->gso_size
= virtio16_to_cpu(vi
->vdev
,
509 if (skb_shinfo(skb
)->gso_size
== 0) {
510 net_warn_ratelimited("%s: zero gso size.\n", dev
->name
);
514 /* Header must be checked, and gso_segs computed. */
515 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
516 skb_shinfo(skb
)->gso_segs
= 0;
519 napi_gro_receive(&rq
->napi
, skb
);
523 dev
->stats
.rx_frame_errors
++;
527 static int add_recvbuf_small(struct virtnet_info
*vi
, struct receive_queue
*rq
,
531 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
534 skb
= __netdev_alloc_skb_ip_align(vi
->dev
, GOOD_PACKET_LEN
, gfp
);
538 skb_put(skb
, GOOD_PACKET_LEN
);
540 hdr
= skb_vnet_hdr(skb
);
541 sg_init_table(rq
->sg
, 2);
542 sg_set_buf(rq
->sg
, hdr
, vi
->hdr_len
);
543 skb_to_sgvec(skb
, rq
->sg
+ 1, 0, skb
->len
);
545 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, 2, skb
, gfp
);
552 static int add_recvbuf_big(struct virtnet_info
*vi
, struct receive_queue
*rq
,
555 struct page
*first
, *list
= NULL
;
559 sg_init_table(rq
->sg
, MAX_SKB_FRAGS
+ 2);
561 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
562 for (i
= MAX_SKB_FRAGS
+ 1; i
> 1; --i
) {
563 first
= get_a_page(rq
, gfp
);
566 give_pages(rq
, list
);
569 sg_set_buf(&rq
->sg
[i
], page_address(first
), PAGE_SIZE
);
571 /* chain new page in list head to match sg */
572 first
->private = (unsigned long)list
;
576 first
= get_a_page(rq
, gfp
);
578 give_pages(rq
, list
);
581 p
= page_address(first
);
583 /* rq->sg[0], rq->sg[1] share the same page */
584 /* a separated rq->sg[0] for header - required in case !any_header_sg */
585 sg_set_buf(&rq
->sg
[0], p
, vi
->hdr_len
);
587 /* rq->sg[1] for data packet, from offset */
588 offset
= sizeof(struct padded_vnet_hdr
);
589 sg_set_buf(&rq
->sg
[1], p
+ offset
, PAGE_SIZE
- offset
);
591 /* chain first in list head */
592 first
->private = (unsigned long)list
;
593 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, MAX_SKB_FRAGS
+ 2,
596 give_pages(rq
, first
);
601 static unsigned int get_mergeable_buf_len(struct ewma_pkt_len
*avg_pkt_len
)
603 const size_t hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
606 len
= hdr_len
+ clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len
),
607 GOOD_PACKET_LEN
, PAGE_SIZE
- hdr_len
);
608 return ALIGN(len
, MERGEABLE_BUFFER_ALIGN
);
611 static int add_recvbuf_mergeable(struct receive_queue
*rq
, gfp_t gfp
)
613 struct page_frag
*alloc_frag
= &rq
->alloc_frag
;
617 unsigned int len
, hole
;
619 len
= get_mergeable_buf_len(&rq
->mrg_avg_pkt_len
);
620 if (unlikely(!skb_page_frag_refill(len
, alloc_frag
, gfp
)))
623 buf
= (char *)page_address(alloc_frag
->page
) + alloc_frag
->offset
;
624 ctx
= mergeable_buf_to_ctx(buf
, len
);
625 get_page(alloc_frag
->page
);
626 alloc_frag
->offset
+= len
;
627 hole
= alloc_frag
->size
- alloc_frag
->offset
;
629 /* To avoid internal fragmentation, if there is very likely not
630 * enough space for another buffer, add the remaining space to
631 * the current buffer. This extra space is not included in
632 * the truesize stored in ctx.
635 alloc_frag
->offset
+= hole
;
638 sg_init_one(rq
->sg
, buf
, len
);
639 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, 1, (void *)ctx
, gfp
);
641 put_page(virt_to_head_page(buf
));
647 * Returns false if we couldn't fill entirely (OOM).
649 * Normally run in the receive path, but can also be run from ndo_open
650 * before we're receiving packets, or from refill_work which is
651 * careful to disable receiving (using napi_disable).
653 static bool try_fill_recv(struct virtnet_info
*vi
, struct receive_queue
*rq
,
661 if (vi
->mergeable_rx_bufs
)
662 err
= add_recvbuf_mergeable(rq
, gfp
);
663 else if (vi
->big_packets
)
664 err
= add_recvbuf_big(vi
, rq
, gfp
);
666 err
= add_recvbuf_small(vi
, rq
, gfp
);
668 oom
= err
== -ENOMEM
;
671 } while (rq
->vq
->num_free
);
672 virtqueue_kick(rq
->vq
);
676 static void skb_recv_done(struct virtqueue
*rvq
)
678 struct virtnet_info
*vi
= rvq
->vdev
->priv
;
679 struct receive_queue
*rq
= &vi
->rq
[vq2rxq(rvq
)];
681 /* Schedule NAPI, Suppress further interrupts if successful. */
682 if (napi_schedule_prep(&rq
->napi
)) {
683 virtqueue_disable_cb(rvq
);
684 __napi_schedule(&rq
->napi
);
688 static void virtnet_napi_enable(struct receive_queue
*rq
)
690 napi_enable(&rq
->napi
);
692 /* If all buffers were filled by other side before we napi_enabled, we
693 * won't get another interrupt, so process any outstanding packets
694 * now. virtnet_poll wants re-enable the queue, so we disable here.
695 * We synchronize against interrupts via NAPI_STATE_SCHED */
696 if (napi_schedule_prep(&rq
->napi
)) {
697 virtqueue_disable_cb(rq
->vq
);
699 __napi_schedule(&rq
->napi
);
704 static void refill_work(struct work_struct
*work
)
706 struct virtnet_info
*vi
=
707 container_of(work
, struct virtnet_info
, refill
.work
);
711 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++) {
712 struct receive_queue
*rq
= &vi
->rq
[i
];
714 napi_disable(&rq
->napi
);
715 still_empty
= !try_fill_recv(vi
, rq
, GFP_KERNEL
);
716 virtnet_napi_enable(rq
);
718 /* In theory, this can happen: if we don't get any buffers in
719 * we will *never* try to fill again.
722 schedule_delayed_work(&vi
->refill
, HZ
/2);
726 static int virtnet_receive(struct receive_queue
*rq
, int budget
)
728 struct virtnet_info
*vi
= rq
->vq
->vdev
->priv
;
729 unsigned int len
, received
= 0;
732 while (received
< budget
&&
733 (buf
= virtqueue_get_buf(rq
->vq
, &len
)) != NULL
) {
734 receive_buf(vi
, rq
, buf
, len
);
738 if (rq
->vq
->num_free
> virtqueue_get_vring_size(rq
->vq
) / 2) {
739 if (!try_fill_recv(vi
, rq
, GFP_ATOMIC
))
740 schedule_delayed_work(&vi
->refill
, 0);
746 static int virtnet_poll(struct napi_struct
*napi
, int budget
)
748 struct receive_queue
*rq
=
749 container_of(napi
, struct receive_queue
, napi
);
750 unsigned int r
, received
;
752 received
= virtnet_receive(rq
, budget
);
754 /* Out of packets? */
755 if (received
< budget
) {
756 r
= virtqueue_enable_cb_prepare(rq
->vq
);
757 napi_complete_done(napi
, received
);
758 if (unlikely(virtqueue_poll(rq
->vq
, r
)) &&
759 napi_schedule_prep(napi
)) {
760 virtqueue_disable_cb(rq
->vq
);
761 __napi_schedule(napi
);
768 #ifdef CONFIG_NET_RX_BUSY_POLL
769 /* must be called with local_bh_disable()d */
770 static int virtnet_busy_poll(struct napi_struct
*napi
)
772 struct receive_queue
*rq
=
773 container_of(napi
, struct receive_queue
, napi
);
774 struct virtnet_info
*vi
= rq
->vq
->vdev
->priv
;
775 int r
, received
= 0, budget
= 4;
777 if (!(vi
->status
& VIRTIO_NET_S_LINK_UP
))
778 return LL_FLUSH_FAILED
;
780 if (!napi_schedule_prep(napi
))
781 return LL_FLUSH_BUSY
;
783 virtqueue_disable_cb(rq
->vq
);
786 received
+= virtnet_receive(rq
, budget
);
788 r
= virtqueue_enable_cb_prepare(rq
->vq
);
789 clear_bit(NAPI_STATE_SCHED
, &napi
->state
);
790 if (unlikely(virtqueue_poll(rq
->vq
, r
)) &&
791 napi_schedule_prep(napi
)) {
792 virtqueue_disable_cb(rq
->vq
);
793 if (received
< budget
) {
797 __napi_schedule(napi
);
803 #endif /* CONFIG_NET_RX_BUSY_POLL */
805 static int virtnet_open(struct net_device
*dev
)
807 struct virtnet_info
*vi
= netdev_priv(dev
);
810 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
811 if (i
< vi
->curr_queue_pairs
)
812 /* Make sure we have some buffers: if oom use wq. */
813 if (!try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
))
814 schedule_delayed_work(&vi
->refill
, 0);
815 virtnet_napi_enable(&vi
->rq
[i
]);
821 static void free_old_xmit_skbs(struct send_queue
*sq
)
825 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
826 struct virtnet_stats
*stats
= this_cpu_ptr(vi
->stats
);
828 while ((skb
= virtqueue_get_buf(sq
->vq
, &len
)) != NULL
) {
829 pr_debug("Sent skb %p\n", skb
);
831 u64_stats_update_begin(&stats
->tx_syncp
);
832 stats
->tx_bytes
+= skb
->len
;
834 u64_stats_update_end(&stats
->tx_syncp
);
836 dev_kfree_skb_any(skb
);
840 static int xmit_skb(struct send_queue
*sq
, struct sk_buff
*skb
)
842 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
843 const unsigned char *dest
= ((struct ethhdr
*)skb
->data
)->h_dest
;
844 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
846 unsigned hdr_len
= vi
->hdr_len
;
849 pr_debug("%s: xmit %p %pM\n", vi
->dev
->name
, skb
, dest
);
851 can_push
= vi
->any_header_sg
&&
852 !((unsigned long)skb
->data
& (__alignof__(*hdr
) - 1)) &&
853 !skb_header_cloned(skb
) && skb_headroom(skb
) >= hdr_len
;
854 /* Even if we can, don't push here yet as this would skew
855 * csum_start offset below. */
857 hdr
= (struct virtio_net_hdr_mrg_rxbuf
*)(skb
->data
- hdr_len
);
859 hdr
= skb_vnet_hdr(skb
);
861 if (skb
->ip_summed
== CHECKSUM_PARTIAL
) {
862 hdr
->hdr
.flags
= VIRTIO_NET_HDR_F_NEEDS_CSUM
;
863 hdr
->hdr
.csum_start
= cpu_to_virtio16(vi
->vdev
,
864 skb_checksum_start_offset(skb
));
865 hdr
->hdr
.csum_offset
= cpu_to_virtio16(vi
->vdev
,
869 hdr
->hdr
.csum_offset
= hdr
->hdr
.csum_start
= 0;
872 if (skb_is_gso(skb
)) {
873 hdr
->hdr
.hdr_len
= cpu_to_virtio16(vi
->vdev
, skb_headlen(skb
));
874 hdr
->hdr
.gso_size
= cpu_to_virtio16(vi
->vdev
,
875 skb_shinfo(skb
)->gso_size
);
876 if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV4
)
877 hdr
->hdr
.gso_type
= VIRTIO_NET_HDR_GSO_TCPV4
;
878 else if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
)
879 hdr
->hdr
.gso_type
= VIRTIO_NET_HDR_GSO_TCPV6
;
880 else if (skb_shinfo(skb
)->gso_type
& SKB_GSO_UDP
)
881 hdr
->hdr
.gso_type
= VIRTIO_NET_HDR_GSO_UDP
;
884 if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCP_ECN
)
885 hdr
->hdr
.gso_type
|= VIRTIO_NET_HDR_GSO_ECN
;
887 hdr
->hdr
.gso_type
= VIRTIO_NET_HDR_GSO_NONE
;
888 hdr
->hdr
.gso_size
= hdr
->hdr
.hdr_len
= 0;
891 if (vi
->mergeable_rx_bufs
)
892 hdr
->num_buffers
= 0;
894 sg_init_table(sq
->sg
, skb_shinfo(skb
)->nr_frags
+ (can_push
? 1 : 2));
896 __skb_push(skb
, hdr_len
);
897 num_sg
= skb_to_sgvec(skb
, sq
->sg
, 0, skb
->len
);
898 /* Pull header back to avoid skew in tx bytes calculations. */
899 __skb_pull(skb
, hdr_len
);
901 sg_set_buf(sq
->sg
, hdr
, hdr_len
);
902 num_sg
= skb_to_sgvec(skb
, sq
->sg
+ 1, 0, skb
->len
) + 1;
904 return virtqueue_add_outbuf(sq
->vq
, sq
->sg
, num_sg
, skb
, GFP_ATOMIC
);
907 static netdev_tx_t
start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
909 struct virtnet_info
*vi
= netdev_priv(dev
);
910 int qnum
= skb_get_queue_mapping(skb
);
911 struct send_queue
*sq
= &vi
->sq
[qnum
];
913 struct netdev_queue
*txq
= netdev_get_tx_queue(dev
, qnum
);
914 bool kick
= !skb
->xmit_more
;
916 /* Free up any pending old buffers before queueing new ones. */
917 free_old_xmit_skbs(sq
);
919 /* timestamp packet in software */
920 skb_tx_timestamp(skb
);
922 /* Try to transmit */
923 err
= xmit_skb(sq
, skb
);
925 /* This should not happen! */
927 dev
->stats
.tx_fifo_errors
++;
930 "Unexpected TXQ (%d) queue failure: %d\n", qnum
, err
);
931 dev
->stats
.tx_dropped
++;
932 dev_kfree_skb_any(skb
);
936 /* Don't wait up for transmitted skbs to be freed. */
940 /* If running out of space, stop queue to avoid getting packets that we
941 * are then unable to transmit.
942 * An alternative would be to force queuing layer to requeue the skb by
943 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
944 * returned in a normal path of operation: it means that driver is not
945 * maintaining the TX queue stop/start state properly, and causes
946 * the stack to do a non-trivial amount of useless work.
947 * Since most packets only take 1 or 2 ring slots, stopping the queue
948 * early means 16 slots are typically wasted.
950 if (sq
->vq
->num_free
< 2+MAX_SKB_FRAGS
) {
951 netif_stop_subqueue(dev
, qnum
);
952 if (unlikely(!virtqueue_enable_cb_delayed(sq
->vq
))) {
953 /* More just got used, free them then recheck. */
954 free_old_xmit_skbs(sq
);
955 if (sq
->vq
->num_free
>= 2+MAX_SKB_FRAGS
) {
956 netif_start_subqueue(dev
, qnum
);
957 virtqueue_disable_cb(sq
->vq
);
962 if (kick
|| netif_xmit_stopped(txq
))
963 virtqueue_kick(sq
->vq
);
969 * Send command via the control virtqueue and check status. Commands
970 * supported by the hypervisor, as indicated by feature bits, should
971 * never fail unless improperly formatted.
973 static bool virtnet_send_command(struct virtnet_info
*vi
, u8
class, u8 cmd
,
974 struct scatterlist
*out
)
976 struct scatterlist
*sgs
[4], hdr
, stat
;
977 struct virtio_net_ctrl_hdr ctrl
;
978 virtio_net_ctrl_ack status
= ~0;
979 unsigned out_num
= 0, tmp
;
981 /* Caller should know better */
982 BUG_ON(!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VQ
));
987 sg_init_one(&hdr
, &ctrl
, sizeof(ctrl
));
988 sgs
[out_num
++] = &hdr
;
991 sgs
[out_num
++] = out
;
993 /* Add return status. */
994 sg_init_one(&stat
, &status
, sizeof(status
));
995 sgs
[out_num
] = &stat
;
997 BUG_ON(out_num
+ 1 > ARRAY_SIZE(sgs
));
998 virtqueue_add_sgs(vi
->cvq
, sgs
, out_num
, 1, vi
, GFP_ATOMIC
);
1000 if (unlikely(!virtqueue_kick(vi
->cvq
)))
1001 return status
== VIRTIO_NET_OK
;
1003 /* Spin for a response, the kick causes an ioport write, trapping
1004 * into the hypervisor, so the request should be handled immediately.
1006 while (!virtqueue_get_buf(vi
->cvq
, &tmp
) &&
1007 !virtqueue_is_broken(vi
->cvq
))
1010 return status
== VIRTIO_NET_OK
;
1013 static int virtnet_set_mac_address(struct net_device
*dev
, void *p
)
1015 struct virtnet_info
*vi
= netdev_priv(dev
);
1016 struct virtio_device
*vdev
= vi
->vdev
;
1018 struct sockaddr
*addr
= p
;
1019 struct scatterlist sg
;
1021 ret
= eth_prepare_mac_addr_change(dev
, p
);
1025 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_MAC_ADDR
)) {
1026 sg_init_one(&sg
, addr
->sa_data
, dev
->addr_len
);
1027 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MAC
,
1028 VIRTIO_NET_CTRL_MAC_ADDR_SET
, &sg
)) {
1029 dev_warn(&vdev
->dev
,
1030 "Failed to set mac address by vq command.\n");
1033 } else if (virtio_has_feature(vdev
, VIRTIO_NET_F_MAC
) &&
1034 !virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
)) {
1037 /* Naturally, this has an atomicity problem. */
1038 for (i
= 0; i
< dev
->addr_len
; i
++)
1039 virtio_cwrite8(vdev
,
1040 offsetof(struct virtio_net_config
, mac
) +
1041 i
, addr
->sa_data
[i
]);
1044 eth_commit_mac_addr_change(dev
, p
);
1049 static struct rtnl_link_stats64
*virtnet_stats(struct net_device
*dev
,
1050 struct rtnl_link_stats64
*tot
)
1052 struct virtnet_info
*vi
= netdev_priv(dev
);
1056 for_each_possible_cpu(cpu
) {
1057 struct virtnet_stats
*stats
= per_cpu_ptr(vi
->stats
, cpu
);
1058 u64 tpackets
, tbytes
, rpackets
, rbytes
;
1061 start
= u64_stats_fetch_begin_irq(&stats
->tx_syncp
);
1062 tpackets
= stats
->tx_packets
;
1063 tbytes
= stats
->tx_bytes
;
1064 } while (u64_stats_fetch_retry_irq(&stats
->tx_syncp
, start
));
1067 start
= u64_stats_fetch_begin_irq(&stats
->rx_syncp
);
1068 rpackets
= stats
->rx_packets
;
1069 rbytes
= stats
->rx_bytes
;
1070 } while (u64_stats_fetch_retry_irq(&stats
->rx_syncp
, start
));
1072 tot
->rx_packets
+= rpackets
;
1073 tot
->tx_packets
+= tpackets
;
1074 tot
->rx_bytes
+= rbytes
;
1075 tot
->tx_bytes
+= tbytes
;
1078 tot
->tx_dropped
= dev
->stats
.tx_dropped
;
1079 tot
->tx_fifo_errors
= dev
->stats
.tx_fifo_errors
;
1080 tot
->rx_dropped
= dev
->stats
.rx_dropped
;
1081 tot
->rx_length_errors
= dev
->stats
.rx_length_errors
;
1082 tot
->rx_frame_errors
= dev
->stats
.rx_frame_errors
;
1087 #ifdef CONFIG_NET_POLL_CONTROLLER
1088 static void virtnet_netpoll(struct net_device
*dev
)
1090 struct virtnet_info
*vi
= netdev_priv(dev
);
1093 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++)
1094 napi_schedule(&vi
->rq
[i
].napi
);
1098 static void virtnet_ack_link_announce(struct virtnet_info
*vi
)
1101 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_ANNOUNCE
,
1102 VIRTIO_NET_CTRL_ANNOUNCE_ACK
, NULL
))
1103 dev_warn(&vi
->dev
->dev
, "Failed to ack link announce.\n");
1107 static int virtnet_set_queues(struct virtnet_info
*vi
, u16 queue_pairs
)
1109 struct scatterlist sg
;
1110 struct virtio_net_ctrl_mq s
;
1111 struct net_device
*dev
= vi
->dev
;
1113 if (!vi
->has_cvq
|| !virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_MQ
))
1116 s
.virtqueue_pairs
= cpu_to_virtio16(vi
->vdev
, queue_pairs
);
1117 sg_init_one(&sg
, &s
, sizeof(s
));
1119 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MQ
,
1120 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET
, &sg
)) {
1121 dev_warn(&dev
->dev
, "Fail to set num of queue pairs to %d\n",
1125 vi
->curr_queue_pairs
= queue_pairs
;
1126 /* virtnet_open() will refill when device is going to up. */
1127 if (dev
->flags
& IFF_UP
)
1128 schedule_delayed_work(&vi
->refill
, 0);
1134 static int virtnet_close(struct net_device
*dev
)
1136 struct virtnet_info
*vi
= netdev_priv(dev
);
1139 /* Make sure refill_work doesn't re-enable napi! */
1140 cancel_delayed_work_sync(&vi
->refill
);
1142 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1143 napi_disable(&vi
->rq
[i
].napi
);
1148 static void virtnet_set_rx_mode(struct net_device
*dev
)
1150 struct virtnet_info
*vi
= netdev_priv(dev
);
1151 struct scatterlist sg
[2];
1152 u8 promisc
, allmulti
;
1153 struct virtio_net_ctrl_mac
*mac_data
;
1154 struct netdev_hw_addr
*ha
;
1160 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1161 if (!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_RX
))
1164 promisc
= ((dev
->flags
& IFF_PROMISC
) != 0);
1165 allmulti
= ((dev
->flags
& IFF_ALLMULTI
) != 0);
1167 sg_init_one(sg
, &promisc
, sizeof(promisc
));
1169 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_RX
,
1170 VIRTIO_NET_CTRL_RX_PROMISC
, sg
))
1171 dev_warn(&dev
->dev
, "Failed to %sable promisc mode.\n",
1172 promisc
? "en" : "dis");
1174 sg_init_one(sg
, &allmulti
, sizeof(allmulti
));
1176 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_RX
,
1177 VIRTIO_NET_CTRL_RX_ALLMULTI
, sg
))
1178 dev_warn(&dev
->dev
, "Failed to %sable allmulti mode.\n",
1179 allmulti
? "en" : "dis");
1181 uc_count
= netdev_uc_count(dev
);
1182 mc_count
= netdev_mc_count(dev
);
1183 /* MAC filter - use one buffer for both lists */
1184 buf
= kzalloc(((uc_count
+ mc_count
) * ETH_ALEN
) +
1185 (2 * sizeof(mac_data
->entries
)), GFP_ATOMIC
);
1190 sg_init_table(sg
, 2);
1192 /* Store the unicast list and count in the front of the buffer */
1193 mac_data
->entries
= cpu_to_virtio32(vi
->vdev
, uc_count
);
1195 netdev_for_each_uc_addr(ha
, dev
)
1196 memcpy(&mac_data
->macs
[i
++][0], ha
->addr
, ETH_ALEN
);
1198 sg_set_buf(&sg
[0], mac_data
,
1199 sizeof(mac_data
->entries
) + (uc_count
* ETH_ALEN
));
1201 /* multicast list and count fill the end */
1202 mac_data
= (void *)&mac_data
->macs
[uc_count
][0];
1204 mac_data
->entries
= cpu_to_virtio32(vi
->vdev
, mc_count
);
1206 netdev_for_each_mc_addr(ha
, dev
)
1207 memcpy(&mac_data
->macs
[i
++][0], ha
->addr
, ETH_ALEN
);
1209 sg_set_buf(&sg
[1], mac_data
,
1210 sizeof(mac_data
->entries
) + (mc_count
* ETH_ALEN
));
1212 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MAC
,
1213 VIRTIO_NET_CTRL_MAC_TABLE_SET
, sg
))
1214 dev_warn(&dev
->dev
, "Failed to set MAC filter table.\n");
1219 static int virtnet_vlan_rx_add_vid(struct net_device
*dev
,
1220 __be16 proto
, u16 vid
)
1222 struct virtnet_info
*vi
= netdev_priv(dev
);
1223 struct scatterlist sg
;
1225 sg_init_one(&sg
, &vid
, sizeof(vid
));
1227 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_VLAN
,
1228 VIRTIO_NET_CTRL_VLAN_ADD
, &sg
))
1229 dev_warn(&dev
->dev
, "Failed to add VLAN ID %d.\n", vid
);
1233 static int virtnet_vlan_rx_kill_vid(struct net_device
*dev
,
1234 __be16 proto
, u16 vid
)
1236 struct virtnet_info
*vi
= netdev_priv(dev
);
1237 struct scatterlist sg
;
1239 sg_init_one(&sg
, &vid
, sizeof(vid
));
1241 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_VLAN
,
1242 VIRTIO_NET_CTRL_VLAN_DEL
, &sg
))
1243 dev_warn(&dev
->dev
, "Failed to kill VLAN ID %d.\n", vid
);
1247 static void virtnet_clean_affinity(struct virtnet_info
*vi
, long hcpu
)
1251 if (vi
->affinity_hint_set
) {
1252 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1253 virtqueue_set_affinity(vi
->rq
[i
].vq
, -1);
1254 virtqueue_set_affinity(vi
->sq
[i
].vq
, -1);
1257 vi
->affinity_hint_set
= false;
1261 static void virtnet_set_affinity(struct virtnet_info
*vi
)
1266 /* In multiqueue mode, when the number of cpu is equal to the number of
1267 * queue pairs, we let the queue pairs to be private to one cpu by
1268 * setting the affinity hint to eliminate the contention.
1270 if (vi
->curr_queue_pairs
== 1 ||
1271 vi
->max_queue_pairs
!= num_online_cpus()) {
1272 virtnet_clean_affinity(vi
, -1);
1277 for_each_online_cpu(cpu
) {
1278 virtqueue_set_affinity(vi
->rq
[i
].vq
, cpu
);
1279 virtqueue_set_affinity(vi
->sq
[i
].vq
, cpu
);
1280 netif_set_xps_queue(vi
->dev
, cpumask_of(cpu
), i
);
1284 vi
->affinity_hint_set
= true;
1287 static int virtnet_cpu_callback(struct notifier_block
*nfb
,
1288 unsigned long action
, void *hcpu
)
1290 struct virtnet_info
*vi
= container_of(nfb
, struct virtnet_info
, nb
);
1292 switch(action
& ~CPU_TASKS_FROZEN
) {
1294 case CPU_DOWN_FAILED
:
1296 virtnet_set_affinity(vi
);
1298 case CPU_DOWN_PREPARE
:
1299 virtnet_clean_affinity(vi
, (long)hcpu
);
1308 static void virtnet_get_ringparam(struct net_device
*dev
,
1309 struct ethtool_ringparam
*ring
)
1311 struct virtnet_info
*vi
= netdev_priv(dev
);
1313 ring
->rx_max_pending
= virtqueue_get_vring_size(vi
->rq
[0].vq
);
1314 ring
->tx_max_pending
= virtqueue_get_vring_size(vi
->sq
[0].vq
);
1315 ring
->rx_pending
= ring
->rx_max_pending
;
1316 ring
->tx_pending
= ring
->tx_max_pending
;
1320 static void virtnet_get_drvinfo(struct net_device
*dev
,
1321 struct ethtool_drvinfo
*info
)
1323 struct virtnet_info
*vi
= netdev_priv(dev
);
1324 struct virtio_device
*vdev
= vi
->vdev
;
1326 strlcpy(info
->driver
, KBUILD_MODNAME
, sizeof(info
->driver
));
1327 strlcpy(info
->version
, VIRTNET_DRIVER_VERSION
, sizeof(info
->version
));
1328 strlcpy(info
->bus_info
, virtio_bus_name(vdev
), sizeof(info
->bus_info
));
1332 /* TODO: Eliminate OOO packets during switching */
1333 static int virtnet_set_channels(struct net_device
*dev
,
1334 struct ethtool_channels
*channels
)
1336 struct virtnet_info
*vi
= netdev_priv(dev
);
1337 u16 queue_pairs
= channels
->combined_count
;
1340 /* We don't support separate rx/tx channels.
1341 * We don't allow setting 'other' channels.
1343 if (channels
->rx_count
|| channels
->tx_count
|| channels
->other_count
)
1346 if (queue_pairs
> vi
->max_queue_pairs
|| queue_pairs
== 0)
1350 err
= virtnet_set_queues(vi
, queue_pairs
);
1352 netif_set_real_num_tx_queues(dev
, queue_pairs
);
1353 netif_set_real_num_rx_queues(dev
, queue_pairs
);
1355 virtnet_set_affinity(vi
);
1362 static void virtnet_get_channels(struct net_device
*dev
,
1363 struct ethtool_channels
*channels
)
1365 struct virtnet_info
*vi
= netdev_priv(dev
);
1367 channels
->combined_count
= vi
->curr_queue_pairs
;
1368 channels
->max_combined
= vi
->max_queue_pairs
;
1369 channels
->max_other
= 0;
1370 channels
->rx_count
= 0;
1371 channels
->tx_count
= 0;
1372 channels
->other_count
= 0;
1375 static const struct ethtool_ops virtnet_ethtool_ops
= {
1376 .get_drvinfo
= virtnet_get_drvinfo
,
1377 .get_link
= ethtool_op_get_link
,
1378 .get_ringparam
= virtnet_get_ringparam
,
1379 .set_channels
= virtnet_set_channels
,
1380 .get_channels
= virtnet_get_channels
,
1381 .get_ts_info
= ethtool_op_get_ts_info
,
1385 #define MAX_MTU 65535
1387 static int virtnet_change_mtu(struct net_device
*dev
, int new_mtu
)
1389 if (new_mtu
< MIN_MTU
|| new_mtu
> MAX_MTU
)
1395 static const struct net_device_ops virtnet_netdev
= {
1396 .ndo_open
= virtnet_open
,
1397 .ndo_stop
= virtnet_close
,
1398 .ndo_start_xmit
= start_xmit
,
1399 .ndo_validate_addr
= eth_validate_addr
,
1400 .ndo_set_mac_address
= virtnet_set_mac_address
,
1401 .ndo_set_rx_mode
= virtnet_set_rx_mode
,
1402 .ndo_change_mtu
= virtnet_change_mtu
,
1403 .ndo_get_stats64
= virtnet_stats
,
1404 .ndo_vlan_rx_add_vid
= virtnet_vlan_rx_add_vid
,
1405 .ndo_vlan_rx_kill_vid
= virtnet_vlan_rx_kill_vid
,
1406 #ifdef CONFIG_NET_POLL_CONTROLLER
1407 .ndo_poll_controller
= virtnet_netpoll
,
1409 #ifdef CONFIG_NET_RX_BUSY_POLL
1410 .ndo_busy_poll
= virtnet_busy_poll
,
1414 static void virtnet_config_changed_work(struct work_struct
*work
)
1416 struct virtnet_info
*vi
=
1417 container_of(work
, struct virtnet_info
, config_work
);
1420 if (virtio_cread_feature(vi
->vdev
, VIRTIO_NET_F_STATUS
,
1421 struct virtio_net_config
, status
, &v
) < 0)
1424 if (v
& VIRTIO_NET_S_ANNOUNCE
) {
1425 netdev_notify_peers(vi
->dev
);
1426 virtnet_ack_link_announce(vi
);
1429 /* Ignore unknown (future) status bits */
1430 v
&= VIRTIO_NET_S_LINK_UP
;
1432 if (vi
->status
== v
)
1437 if (vi
->status
& VIRTIO_NET_S_LINK_UP
) {
1438 netif_carrier_on(vi
->dev
);
1439 netif_tx_wake_all_queues(vi
->dev
);
1441 netif_carrier_off(vi
->dev
);
1442 netif_tx_stop_all_queues(vi
->dev
);
1446 static void virtnet_config_changed(struct virtio_device
*vdev
)
1448 struct virtnet_info
*vi
= vdev
->priv
;
1450 schedule_work(&vi
->config_work
);
1453 static void virtnet_free_queues(struct virtnet_info
*vi
)
1457 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1458 napi_hash_del(&vi
->rq
[i
].napi
);
1459 netif_napi_del(&vi
->rq
[i
].napi
);
1466 static void free_receive_bufs(struct virtnet_info
*vi
)
1470 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1471 while (vi
->rq
[i
].pages
)
1472 __free_pages(get_a_page(&vi
->rq
[i
], GFP_KERNEL
), 0);
1476 static void free_receive_page_frags(struct virtnet_info
*vi
)
1479 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1480 if (vi
->rq
[i
].alloc_frag
.page
)
1481 put_page(vi
->rq
[i
].alloc_frag
.page
);
1484 static void free_unused_bufs(struct virtnet_info
*vi
)
1489 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1490 struct virtqueue
*vq
= vi
->sq
[i
].vq
;
1491 while ((buf
= virtqueue_detach_unused_buf(vq
)) != NULL
)
1495 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1496 struct virtqueue
*vq
= vi
->rq
[i
].vq
;
1498 while ((buf
= virtqueue_detach_unused_buf(vq
)) != NULL
) {
1499 if (vi
->mergeable_rx_bufs
) {
1500 unsigned long ctx
= (unsigned long)buf
;
1501 void *base
= mergeable_ctx_to_buf_address(ctx
);
1502 put_page(virt_to_head_page(base
));
1503 } else if (vi
->big_packets
) {
1504 give_pages(&vi
->rq
[i
], buf
);
1512 static void virtnet_del_vqs(struct virtnet_info
*vi
)
1514 struct virtio_device
*vdev
= vi
->vdev
;
1516 virtnet_clean_affinity(vi
, -1);
1518 vdev
->config
->del_vqs(vdev
);
1520 virtnet_free_queues(vi
);
1523 static int virtnet_find_vqs(struct virtnet_info
*vi
)
1525 vq_callback_t
**callbacks
;
1526 struct virtqueue
**vqs
;
1531 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
1532 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
1533 * possible control vq.
1535 total_vqs
= vi
->max_queue_pairs
* 2 +
1536 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VQ
);
1538 /* Allocate space for find_vqs parameters */
1539 vqs
= kzalloc(total_vqs
* sizeof(*vqs
), GFP_KERNEL
);
1542 callbacks
= kmalloc(total_vqs
* sizeof(*callbacks
), GFP_KERNEL
);
1545 names
= kmalloc(total_vqs
* sizeof(*names
), GFP_KERNEL
);
1549 /* Parameters for control virtqueue, if any */
1551 callbacks
[total_vqs
- 1] = NULL
;
1552 names
[total_vqs
- 1] = "control";
1555 /* Allocate/initialize parameters for send/receive virtqueues */
1556 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1557 callbacks
[rxq2vq(i
)] = skb_recv_done
;
1558 callbacks
[txq2vq(i
)] = skb_xmit_done
;
1559 sprintf(vi
->rq
[i
].name
, "input.%d", i
);
1560 sprintf(vi
->sq
[i
].name
, "output.%d", i
);
1561 names
[rxq2vq(i
)] = vi
->rq
[i
].name
;
1562 names
[txq2vq(i
)] = vi
->sq
[i
].name
;
1565 ret
= vi
->vdev
->config
->find_vqs(vi
->vdev
, total_vqs
, vqs
, callbacks
,
1571 vi
->cvq
= vqs
[total_vqs
- 1];
1572 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VLAN
))
1573 vi
->dev
->features
|= NETIF_F_HW_VLAN_CTAG_FILTER
;
1576 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1577 vi
->rq
[i
].vq
= vqs
[rxq2vq(i
)];
1578 vi
->sq
[i
].vq
= vqs
[txq2vq(i
)];
1597 static int virtnet_alloc_queues(struct virtnet_info
*vi
)
1601 vi
->sq
= kzalloc(sizeof(*vi
->sq
) * vi
->max_queue_pairs
, GFP_KERNEL
);
1604 vi
->rq
= kzalloc(sizeof(*vi
->rq
) * vi
->max_queue_pairs
, GFP_KERNEL
);
1608 INIT_DELAYED_WORK(&vi
->refill
, refill_work
);
1609 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1610 vi
->rq
[i
].pages
= NULL
;
1611 netif_napi_add(vi
->dev
, &vi
->rq
[i
].napi
, virtnet_poll
,
1614 sg_init_table(vi
->rq
[i
].sg
, ARRAY_SIZE(vi
->rq
[i
].sg
));
1615 ewma_pkt_len_init(&vi
->rq
[i
].mrg_avg_pkt_len
);
1616 sg_init_table(vi
->sq
[i
].sg
, ARRAY_SIZE(vi
->sq
[i
].sg
));
1627 static int init_vqs(struct virtnet_info
*vi
)
1631 /* Allocate send & receive queues */
1632 ret
= virtnet_alloc_queues(vi
);
1636 ret
= virtnet_find_vqs(vi
);
1641 virtnet_set_affinity(vi
);
1647 virtnet_free_queues(vi
);
1653 static ssize_t
mergeable_rx_buffer_size_show(struct netdev_rx_queue
*queue
,
1654 struct rx_queue_attribute
*attribute
, char *buf
)
1656 struct virtnet_info
*vi
= netdev_priv(queue
->dev
);
1657 unsigned int queue_index
= get_netdev_rx_queue_index(queue
);
1658 struct ewma_pkt_len
*avg
;
1660 BUG_ON(queue_index
>= vi
->max_queue_pairs
);
1661 avg
= &vi
->rq
[queue_index
].mrg_avg_pkt_len
;
1662 return sprintf(buf
, "%u\n", get_mergeable_buf_len(avg
));
1665 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute
=
1666 __ATTR_RO(mergeable_rx_buffer_size
);
1668 static struct attribute
*virtio_net_mrg_rx_attrs
[] = {
1669 &mergeable_rx_buffer_size_attribute
.attr
,
1673 static const struct attribute_group virtio_net_mrg_rx_group
= {
1674 .name
= "virtio_net",
1675 .attrs
= virtio_net_mrg_rx_attrs
1679 static bool virtnet_fail_on_feature(struct virtio_device
*vdev
,
1681 const char *fname
, const char *dname
)
1683 if (!virtio_has_feature(vdev
, fbit
))
1686 dev_err(&vdev
->dev
, "device advertises feature %s but not %s",
1692 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
1693 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
1695 static bool virtnet_validate_features(struct virtio_device
*vdev
)
1697 if (!virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
) &&
1698 (VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_RX
,
1699 "VIRTIO_NET_F_CTRL_VQ") ||
1700 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_VLAN
,
1701 "VIRTIO_NET_F_CTRL_VQ") ||
1702 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_GUEST_ANNOUNCE
,
1703 "VIRTIO_NET_F_CTRL_VQ") ||
1704 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_MQ
, "VIRTIO_NET_F_CTRL_VQ") ||
1705 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_MAC_ADDR
,
1706 "VIRTIO_NET_F_CTRL_VQ"))) {
1713 static int virtnet_probe(struct virtio_device
*vdev
)
1716 struct net_device
*dev
;
1717 struct virtnet_info
*vi
;
1718 u16 max_queue_pairs
;
1720 if (!vdev
->config
->get
) {
1721 dev_err(&vdev
->dev
, "%s failure: config access disabled\n",
1726 if (!virtnet_validate_features(vdev
))
1729 /* Find if host supports multiqueue virtio_net device */
1730 err
= virtio_cread_feature(vdev
, VIRTIO_NET_F_MQ
,
1731 struct virtio_net_config
,
1732 max_virtqueue_pairs
, &max_queue_pairs
);
1734 /* We need at least 2 queue's */
1735 if (err
|| max_queue_pairs
< VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN
||
1736 max_queue_pairs
> VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX
||
1737 !virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
))
1738 max_queue_pairs
= 1;
1740 /* Allocate ourselves a network device with room for our info */
1741 dev
= alloc_etherdev_mq(sizeof(struct virtnet_info
), max_queue_pairs
);
1745 /* Set up network device as normal. */
1746 dev
->priv_flags
|= IFF_UNICAST_FLT
| IFF_LIVE_ADDR_CHANGE
;
1747 dev
->netdev_ops
= &virtnet_netdev
;
1748 dev
->features
= NETIF_F_HIGHDMA
;
1750 dev
->ethtool_ops
= &virtnet_ethtool_ops
;
1751 SET_NETDEV_DEV(dev
, &vdev
->dev
);
1753 /* Do we support "hardware" checksums? */
1754 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CSUM
)) {
1755 /* This opens up the world of extra features. */
1756 dev
->hw_features
|= NETIF_F_HW_CSUM
| NETIF_F_SG
;
1758 dev
->features
|= NETIF_F_HW_CSUM
| NETIF_F_SG
;
1760 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GSO
)) {
1761 dev
->hw_features
|= NETIF_F_TSO
| NETIF_F_UFO
1762 | NETIF_F_TSO_ECN
| NETIF_F_TSO6
;
1764 /* Individual feature bits: what can host handle? */
1765 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_TSO4
))
1766 dev
->hw_features
|= NETIF_F_TSO
;
1767 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_TSO6
))
1768 dev
->hw_features
|= NETIF_F_TSO6
;
1769 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_ECN
))
1770 dev
->hw_features
|= NETIF_F_TSO_ECN
;
1771 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_UFO
))
1772 dev
->hw_features
|= NETIF_F_UFO
;
1774 dev
->features
|= NETIF_F_GSO_ROBUST
;
1777 dev
->features
|= dev
->hw_features
& (NETIF_F_ALL_TSO
|NETIF_F_UFO
);
1778 /* (!csum && gso) case will be fixed by register_netdev() */
1780 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_CSUM
))
1781 dev
->features
|= NETIF_F_RXCSUM
;
1783 dev
->vlan_features
= dev
->features
;
1785 /* Configuration may specify what MAC to use. Otherwise random. */
1786 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MAC
))
1787 virtio_cread_bytes(vdev
,
1788 offsetof(struct virtio_net_config
, mac
),
1789 dev
->dev_addr
, dev
->addr_len
);
1791 eth_hw_addr_random(dev
);
1793 /* Set up our device-specific information */
1794 vi
= netdev_priv(dev
);
1798 vi
->stats
= alloc_percpu(struct virtnet_stats
);
1800 if (vi
->stats
== NULL
)
1803 for_each_possible_cpu(i
) {
1804 struct virtnet_stats
*virtnet_stats
;
1805 virtnet_stats
= per_cpu_ptr(vi
->stats
, i
);
1806 u64_stats_init(&virtnet_stats
->tx_syncp
);
1807 u64_stats_init(&virtnet_stats
->rx_syncp
);
1810 INIT_WORK(&vi
->config_work
, virtnet_config_changed_work
);
1812 /* If we can receive ANY GSO packets, we must allocate large ones. */
1813 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_TSO4
) ||
1814 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_TSO6
) ||
1815 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_ECN
) ||
1816 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_UFO
))
1817 vi
->big_packets
= true;
1819 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MRG_RXBUF
))
1820 vi
->mergeable_rx_bufs
= true;
1822 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MRG_RXBUF
) ||
1823 virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
))
1824 vi
->hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
1826 vi
->hdr_len
= sizeof(struct virtio_net_hdr
);
1828 if (virtio_has_feature(vdev
, VIRTIO_F_ANY_LAYOUT
) ||
1829 virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
))
1830 vi
->any_header_sg
= true;
1832 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
))
1835 if (vi
->any_header_sg
)
1836 dev
->needed_headroom
= vi
->hdr_len
;
1838 /* Use single tx/rx queue pair as default */
1839 vi
->curr_queue_pairs
= 1;
1840 vi
->max_queue_pairs
= max_queue_pairs
;
1842 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
1848 if (vi
->mergeable_rx_bufs
)
1849 dev
->sysfs_rx_queue_group
= &virtio_net_mrg_rx_group
;
1851 netif_set_real_num_tx_queues(dev
, vi
->curr_queue_pairs
);
1852 netif_set_real_num_rx_queues(dev
, vi
->curr_queue_pairs
);
1854 err
= register_netdev(dev
);
1856 pr_debug("virtio_net: registering device failed\n");
1860 virtio_device_ready(vdev
);
1862 /* Last of all, set up some receive buffers. */
1863 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++) {
1864 try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
);
1866 /* If we didn't even get one input buffer, we're useless. */
1867 if (vi
->rq
[i
].vq
->num_free
==
1868 virtqueue_get_vring_size(vi
->rq
[i
].vq
)) {
1869 free_unused_bufs(vi
);
1871 goto free_recv_bufs
;
1875 vi
->nb
.notifier_call
= &virtnet_cpu_callback
;
1876 err
= register_hotcpu_notifier(&vi
->nb
);
1878 pr_debug("virtio_net: registering cpu notifier failed\n");
1879 goto free_recv_bufs
;
1882 /* Assume link up if device can't report link status,
1883 otherwise get link status from config. */
1884 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_STATUS
)) {
1885 netif_carrier_off(dev
);
1886 schedule_work(&vi
->config_work
);
1888 vi
->status
= VIRTIO_NET_S_LINK_UP
;
1889 netif_carrier_on(dev
);
1892 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
1893 dev
->name
, max_queue_pairs
);
1898 vi
->vdev
->config
->reset(vdev
);
1900 free_receive_bufs(vi
);
1901 unregister_netdev(dev
);
1903 cancel_delayed_work_sync(&vi
->refill
);
1904 free_receive_page_frags(vi
);
1905 virtnet_del_vqs(vi
);
1907 free_percpu(vi
->stats
);
1913 static void remove_vq_common(struct virtnet_info
*vi
)
1915 vi
->vdev
->config
->reset(vi
->vdev
);
1917 /* Free unused buffers in both send and recv, if any. */
1918 free_unused_bufs(vi
);
1920 free_receive_bufs(vi
);
1922 free_receive_page_frags(vi
);
1924 virtnet_del_vqs(vi
);
1927 static void virtnet_remove(struct virtio_device
*vdev
)
1929 struct virtnet_info
*vi
= vdev
->priv
;
1931 unregister_hotcpu_notifier(&vi
->nb
);
1933 /* Make sure no work handler is accessing the device. */
1934 flush_work(&vi
->config_work
);
1936 unregister_netdev(vi
->dev
);
1938 remove_vq_common(vi
);
1940 free_percpu(vi
->stats
);
1941 free_netdev(vi
->dev
);
1944 #ifdef CONFIG_PM_SLEEP
1945 static int virtnet_freeze(struct virtio_device
*vdev
)
1947 struct virtnet_info
*vi
= vdev
->priv
;
1950 unregister_hotcpu_notifier(&vi
->nb
);
1952 /* Make sure no work handler is accessing the device */
1953 flush_work(&vi
->config_work
);
1955 netif_device_detach(vi
->dev
);
1956 cancel_delayed_work_sync(&vi
->refill
);
1958 if (netif_running(vi
->dev
)) {
1959 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1960 napi_disable(&vi
->rq
[i
].napi
);
1963 remove_vq_common(vi
);
1968 static int virtnet_restore(struct virtio_device
*vdev
)
1970 struct virtnet_info
*vi
= vdev
->priv
;
1977 virtio_device_ready(vdev
);
1979 if (netif_running(vi
->dev
)) {
1980 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++)
1981 if (!try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
))
1982 schedule_delayed_work(&vi
->refill
, 0);
1984 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1985 virtnet_napi_enable(&vi
->rq
[i
]);
1988 netif_device_attach(vi
->dev
);
1991 virtnet_set_queues(vi
, vi
->curr_queue_pairs
);
1994 err
= register_hotcpu_notifier(&vi
->nb
);
2002 static struct virtio_device_id id_table
[] = {
2003 { VIRTIO_ID_NET
, VIRTIO_DEV_ANY_ID
},
2007 static unsigned int features
[] = {
2008 VIRTIO_NET_F_CSUM
, VIRTIO_NET_F_GUEST_CSUM
,
2009 VIRTIO_NET_F_GSO
, VIRTIO_NET_F_MAC
,
2010 VIRTIO_NET_F_HOST_TSO4
, VIRTIO_NET_F_HOST_UFO
, VIRTIO_NET_F_HOST_TSO6
,
2011 VIRTIO_NET_F_HOST_ECN
, VIRTIO_NET_F_GUEST_TSO4
, VIRTIO_NET_F_GUEST_TSO6
,
2012 VIRTIO_NET_F_GUEST_ECN
, VIRTIO_NET_F_GUEST_UFO
,
2013 VIRTIO_NET_F_MRG_RXBUF
, VIRTIO_NET_F_STATUS
, VIRTIO_NET_F_CTRL_VQ
,
2014 VIRTIO_NET_F_CTRL_RX
, VIRTIO_NET_F_CTRL_VLAN
,
2015 VIRTIO_NET_F_GUEST_ANNOUNCE
, VIRTIO_NET_F_MQ
,
2016 VIRTIO_NET_F_CTRL_MAC_ADDR
,
2017 VIRTIO_F_ANY_LAYOUT
,
2020 static struct virtio_driver virtio_net_driver
= {
2021 .feature_table
= features
,
2022 .feature_table_size
= ARRAY_SIZE(features
),
2023 .driver
.name
= KBUILD_MODNAME
,
2024 .driver
.owner
= THIS_MODULE
,
2025 .id_table
= id_table
,
2026 .probe
= virtnet_probe
,
2027 .remove
= virtnet_remove
,
2028 .config_changed
= virtnet_config_changed
,
2029 #ifdef CONFIG_PM_SLEEP
2030 .freeze
= virtnet_freeze
,
2031 .restore
= virtnet_restore
,
2035 module_virtio_driver(virtio_net_driver
);
2037 MODULE_DEVICE_TABLE(virtio
, id_table
);
2038 MODULE_DESCRIPTION("Virtio network driver");
2039 MODULE_LICENSE("GPL");