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
;
144 /* Control VQ buffers: protected by the rtnl lock */
145 struct virtio_net_ctrl_hdr ctrl_hdr
;
146 virtio_net_ctrl_ack ctrl_status
;
151 struct padded_vnet_hdr
{
152 struct virtio_net_hdr_mrg_rxbuf hdr
;
154 * hdr is in a separate sg buffer, and data sg buffer shares same page
155 * with this header sg. This padding makes next sg 16 byte aligned
161 /* Converting between virtqueue no. and kernel tx/rx queue no.
162 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
164 static int vq2txq(struct virtqueue
*vq
)
166 return (vq
->index
- 1) / 2;
169 static int txq2vq(int txq
)
174 static int vq2rxq(struct virtqueue
*vq
)
176 return vq
->index
/ 2;
179 static int rxq2vq(int rxq
)
184 static inline struct virtio_net_hdr_mrg_rxbuf
*skb_vnet_hdr(struct sk_buff
*skb
)
186 return (struct virtio_net_hdr_mrg_rxbuf
*)skb
->cb
;
190 * private is used to chain pages for big packets, put the whole
191 * most recent used list in the beginning for reuse
193 static void give_pages(struct receive_queue
*rq
, struct page
*page
)
197 /* Find end of list, sew whole thing into vi->rq.pages. */
198 for (end
= page
; end
->private; end
= (struct page
*)end
->private);
199 end
->private = (unsigned long)rq
->pages
;
203 static struct page
*get_a_page(struct receive_queue
*rq
, gfp_t gfp_mask
)
205 struct page
*p
= rq
->pages
;
208 rq
->pages
= (struct page
*)p
->private;
209 /* clear private here, it is used to chain pages */
212 p
= alloc_page(gfp_mask
);
216 static void skb_xmit_done(struct virtqueue
*vq
)
218 struct virtnet_info
*vi
= vq
->vdev
->priv
;
220 /* Suppress further interrupts. */
221 virtqueue_disable_cb(vq
);
223 /* We were probably waiting for more output buffers. */
224 netif_wake_subqueue(vi
->dev
, vq2txq(vq
));
227 static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx
)
229 unsigned int truesize
= mrg_ctx
& (MERGEABLE_BUFFER_ALIGN
- 1);
230 return (truesize
+ 1) * MERGEABLE_BUFFER_ALIGN
;
233 static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx
)
235 return (void *)(mrg_ctx
& -MERGEABLE_BUFFER_ALIGN
);
239 static unsigned long mergeable_buf_to_ctx(void *buf
, unsigned int truesize
)
241 unsigned int size
= truesize
/ MERGEABLE_BUFFER_ALIGN
;
242 return (unsigned long)buf
| (size
- 1);
245 /* Called from bottom half context */
246 static struct sk_buff
*page_to_skb(struct virtnet_info
*vi
,
247 struct receive_queue
*rq
,
248 struct page
*page
, unsigned int offset
,
249 unsigned int len
, unsigned int truesize
)
252 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
253 unsigned int copy
, hdr_len
, hdr_padded_len
;
256 p
= page_address(page
) + offset
;
258 /* copy small packet so we can reuse these pages for small data */
259 skb
= netdev_alloc_skb_ip_align(vi
->dev
, GOOD_COPY_LEN
);
263 hdr
= skb_vnet_hdr(skb
);
265 hdr_len
= vi
->hdr_len
;
266 if (vi
->mergeable_rx_bufs
)
267 hdr_padded_len
= sizeof *hdr
;
269 hdr_padded_len
= sizeof(struct padded_vnet_hdr
);
271 memcpy(hdr
, p
, hdr_len
);
274 offset
+= hdr_padded_len
;
278 if (copy
> skb_tailroom(skb
))
279 copy
= skb_tailroom(skb
);
280 memcpy(skb_put(skb
, copy
), p
, copy
);
285 if (vi
->mergeable_rx_bufs
) {
287 skb_add_rx_frag(skb
, 0, page
, offset
, len
, truesize
);
294 * Verify that we can indeed put this data into a skb.
295 * This is here to handle cases when the device erroneously
296 * tries to receive more than is possible. This is usually
297 * the case of a broken device.
299 if (unlikely(len
> MAX_SKB_FRAGS
* PAGE_SIZE
)) {
300 net_dbg_ratelimited("%s: too much data\n", skb
->dev
->name
);
304 BUG_ON(offset
>= PAGE_SIZE
);
306 unsigned int frag_size
= min((unsigned)PAGE_SIZE
- offset
, len
);
307 skb_add_rx_frag(skb
, skb_shinfo(skb
)->nr_frags
, page
, offset
,
308 frag_size
, truesize
);
310 page
= (struct page
*)page
->private;
315 give_pages(rq
, page
);
320 static struct sk_buff
*receive_small(struct virtnet_info
*vi
, void *buf
, unsigned int len
)
322 struct sk_buff
* skb
= buf
;
330 static struct sk_buff
*receive_big(struct net_device
*dev
,
331 struct virtnet_info
*vi
,
332 struct receive_queue
*rq
,
336 struct page
*page
= buf
;
337 struct sk_buff
*skb
= page_to_skb(vi
, rq
, page
, 0, len
, PAGE_SIZE
);
345 dev
->stats
.rx_dropped
++;
346 give_pages(rq
, page
);
350 static struct sk_buff
*receive_mergeable(struct net_device
*dev
,
351 struct virtnet_info
*vi
,
352 struct receive_queue
*rq
,
356 void *buf
= mergeable_ctx_to_buf_address(ctx
);
357 struct virtio_net_hdr_mrg_rxbuf
*hdr
= buf
;
358 u16 num_buf
= virtio16_to_cpu(vi
->vdev
, hdr
->num_buffers
);
359 struct page
*page
= virt_to_head_page(buf
);
360 int offset
= buf
- page_address(page
);
361 unsigned int truesize
= max(len
, mergeable_ctx_to_buf_truesize(ctx
));
363 struct sk_buff
*head_skb
= page_to_skb(vi
, rq
, page
, offset
, len
,
365 struct sk_buff
*curr_skb
= head_skb
;
367 if (unlikely(!curr_skb
))
372 ctx
= (unsigned long)virtqueue_get_buf(rq
->vq
, &len
);
373 if (unlikely(!ctx
)) {
374 pr_debug("%s: rx error: %d buffers out of %d missing\n",
376 virtio16_to_cpu(vi
->vdev
,
378 dev
->stats
.rx_length_errors
++;
382 buf
= mergeable_ctx_to_buf_address(ctx
);
383 page
= virt_to_head_page(buf
);
385 num_skb_frags
= skb_shinfo(curr_skb
)->nr_frags
;
386 if (unlikely(num_skb_frags
== MAX_SKB_FRAGS
)) {
387 struct sk_buff
*nskb
= alloc_skb(0, GFP_ATOMIC
);
391 if (curr_skb
== head_skb
)
392 skb_shinfo(curr_skb
)->frag_list
= nskb
;
394 curr_skb
->next
= nskb
;
396 head_skb
->truesize
+= nskb
->truesize
;
399 truesize
= max(len
, mergeable_ctx_to_buf_truesize(ctx
));
400 if (curr_skb
!= head_skb
) {
401 head_skb
->data_len
+= len
;
402 head_skb
->len
+= len
;
403 head_skb
->truesize
+= truesize
;
405 offset
= buf
- page_address(page
);
406 if (skb_can_coalesce(curr_skb
, num_skb_frags
, page
, offset
)) {
408 skb_coalesce_rx_frag(curr_skb
, num_skb_frags
- 1,
411 skb_add_rx_frag(curr_skb
, num_skb_frags
, page
,
412 offset
, len
, truesize
);
416 ewma_pkt_len_add(&rq
->mrg_avg_pkt_len
, head_skb
->len
);
422 ctx
= (unsigned long)virtqueue_get_buf(rq
->vq
, &len
);
423 if (unlikely(!ctx
)) {
424 pr_debug("%s: rx error: %d buffers missing\n",
426 dev
->stats
.rx_length_errors
++;
429 page
= virt_to_head_page(mergeable_ctx_to_buf_address(ctx
));
433 dev
->stats
.rx_dropped
++;
434 dev_kfree_skb(head_skb
);
438 static void receive_buf(struct virtnet_info
*vi
, struct receive_queue
*rq
,
439 void *buf
, unsigned int len
)
441 struct net_device
*dev
= vi
->dev
;
442 struct virtnet_stats
*stats
= this_cpu_ptr(vi
->stats
);
444 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
446 if (unlikely(len
< vi
->hdr_len
+ ETH_HLEN
)) {
447 pr_debug("%s: short packet %i\n", dev
->name
, len
);
448 dev
->stats
.rx_length_errors
++;
449 if (vi
->mergeable_rx_bufs
) {
450 unsigned long ctx
= (unsigned long)buf
;
451 void *base
= mergeable_ctx_to_buf_address(ctx
);
452 put_page(virt_to_head_page(base
));
453 } else if (vi
->big_packets
) {
461 if (vi
->mergeable_rx_bufs
)
462 skb
= receive_mergeable(dev
, vi
, rq
, (unsigned long)buf
, len
);
463 else if (vi
->big_packets
)
464 skb
= receive_big(dev
, vi
, rq
, buf
, len
);
466 skb
= receive_small(vi
, buf
, len
);
471 hdr
= skb_vnet_hdr(skb
);
473 u64_stats_update_begin(&stats
->rx_syncp
);
474 stats
->rx_bytes
+= skb
->len
;
476 u64_stats_update_end(&stats
->rx_syncp
);
478 if (hdr
->hdr
.flags
& VIRTIO_NET_HDR_F_NEEDS_CSUM
) {
479 pr_debug("Needs csum!\n");
480 if (!skb_partial_csum_set(skb
,
481 virtio16_to_cpu(vi
->vdev
, hdr
->hdr
.csum_start
),
482 virtio16_to_cpu(vi
->vdev
, hdr
->hdr
.csum_offset
)))
484 } else if (hdr
->hdr
.flags
& VIRTIO_NET_HDR_F_DATA_VALID
) {
485 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
488 skb
->protocol
= eth_type_trans(skb
, dev
);
489 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
490 ntohs(skb
->protocol
), skb
->len
, skb
->pkt_type
);
492 if (hdr
->hdr
.gso_type
!= VIRTIO_NET_HDR_GSO_NONE
) {
494 switch (hdr
->hdr
.gso_type
& ~VIRTIO_NET_HDR_GSO_ECN
) {
495 case VIRTIO_NET_HDR_GSO_TCPV4
:
496 skb_shinfo(skb
)->gso_type
= SKB_GSO_TCPV4
;
498 case VIRTIO_NET_HDR_GSO_UDP
:
499 skb_shinfo(skb
)->gso_type
= SKB_GSO_UDP
;
501 case VIRTIO_NET_HDR_GSO_TCPV6
:
502 skb_shinfo(skb
)->gso_type
= SKB_GSO_TCPV6
;
505 net_warn_ratelimited("%s: bad gso type %u.\n",
506 dev
->name
, hdr
->hdr
.gso_type
);
510 if (hdr
->hdr
.gso_type
& VIRTIO_NET_HDR_GSO_ECN
)
511 skb_shinfo(skb
)->gso_type
|= SKB_GSO_TCP_ECN
;
513 skb_shinfo(skb
)->gso_size
= virtio16_to_cpu(vi
->vdev
,
515 if (skb_shinfo(skb
)->gso_size
== 0) {
516 net_warn_ratelimited("%s: zero gso size.\n", dev
->name
);
520 /* Header must be checked, and gso_segs computed. */
521 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
522 skb_shinfo(skb
)->gso_segs
= 0;
525 napi_gro_receive(&rq
->napi
, skb
);
529 dev
->stats
.rx_frame_errors
++;
533 static int add_recvbuf_small(struct virtnet_info
*vi
, struct receive_queue
*rq
,
537 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
540 skb
= __netdev_alloc_skb_ip_align(vi
->dev
, GOOD_PACKET_LEN
, gfp
);
544 skb_put(skb
, GOOD_PACKET_LEN
);
546 hdr
= skb_vnet_hdr(skb
);
547 sg_init_table(rq
->sg
, 2);
548 sg_set_buf(rq
->sg
, hdr
, vi
->hdr_len
);
549 skb_to_sgvec(skb
, rq
->sg
+ 1, 0, skb
->len
);
551 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, 2, skb
, gfp
);
558 static int add_recvbuf_big(struct virtnet_info
*vi
, struct receive_queue
*rq
,
561 struct page
*first
, *list
= NULL
;
565 sg_init_table(rq
->sg
, MAX_SKB_FRAGS
+ 2);
567 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
568 for (i
= MAX_SKB_FRAGS
+ 1; i
> 1; --i
) {
569 first
= get_a_page(rq
, gfp
);
572 give_pages(rq
, list
);
575 sg_set_buf(&rq
->sg
[i
], page_address(first
), PAGE_SIZE
);
577 /* chain new page in list head to match sg */
578 first
->private = (unsigned long)list
;
582 first
= get_a_page(rq
, gfp
);
584 give_pages(rq
, list
);
587 p
= page_address(first
);
589 /* rq->sg[0], rq->sg[1] share the same page */
590 /* a separated rq->sg[0] for header - required in case !any_header_sg */
591 sg_set_buf(&rq
->sg
[0], p
, vi
->hdr_len
);
593 /* rq->sg[1] for data packet, from offset */
594 offset
= sizeof(struct padded_vnet_hdr
);
595 sg_set_buf(&rq
->sg
[1], p
+ offset
, PAGE_SIZE
- offset
);
597 /* chain first in list head */
598 first
->private = (unsigned long)list
;
599 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, MAX_SKB_FRAGS
+ 2,
602 give_pages(rq
, first
);
607 static unsigned int get_mergeable_buf_len(struct ewma_pkt_len
*avg_pkt_len
)
609 const size_t hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
612 len
= hdr_len
+ clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len
),
613 GOOD_PACKET_LEN
, PAGE_SIZE
- hdr_len
);
614 return ALIGN(len
, MERGEABLE_BUFFER_ALIGN
);
617 static int add_recvbuf_mergeable(struct receive_queue
*rq
, gfp_t gfp
)
619 struct page_frag
*alloc_frag
= &rq
->alloc_frag
;
623 unsigned int len
, hole
;
625 len
= get_mergeable_buf_len(&rq
->mrg_avg_pkt_len
);
626 if (unlikely(!skb_page_frag_refill(len
, alloc_frag
, gfp
)))
629 buf
= (char *)page_address(alloc_frag
->page
) + alloc_frag
->offset
;
630 ctx
= mergeable_buf_to_ctx(buf
, len
);
631 get_page(alloc_frag
->page
);
632 alloc_frag
->offset
+= len
;
633 hole
= alloc_frag
->size
- alloc_frag
->offset
;
635 /* To avoid internal fragmentation, if there is very likely not
636 * enough space for another buffer, add the remaining space to
637 * the current buffer. This extra space is not included in
638 * the truesize stored in ctx.
641 alloc_frag
->offset
+= hole
;
644 sg_init_one(rq
->sg
, buf
, len
);
645 err
= virtqueue_add_inbuf(rq
->vq
, rq
->sg
, 1, (void *)ctx
, gfp
);
647 put_page(virt_to_head_page(buf
));
653 * Returns false if we couldn't fill entirely (OOM).
655 * Normally run in the receive path, but can also be run from ndo_open
656 * before we're receiving packets, or from refill_work which is
657 * careful to disable receiving (using napi_disable).
659 static bool try_fill_recv(struct virtnet_info
*vi
, struct receive_queue
*rq
,
667 if (vi
->mergeable_rx_bufs
)
668 err
= add_recvbuf_mergeable(rq
, gfp
);
669 else if (vi
->big_packets
)
670 err
= add_recvbuf_big(vi
, rq
, gfp
);
672 err
= add_recvbuf_small(vi
, rq
, gfp
);
674 oom
= err
== -ENOMEM
;
677 } while (rq
->vq
->num_free
);
678 virtqueue_kick(rq
->vq
);
682 static void skb_recv_done(struct virtqueue
*rvq
)
684 struct virtnet_info
*vi
= rvq
->vdev
->priv
;
685 struct receive_queue
*rq
= &vi
->rq
[vq2rxq(rvq
)];
687 /* Schedule NAPI, Suppress further interrupts if successful. */
688 if (napi_schedule_prep(&rq
->napi
)) {
689 virtqueue_disable_cb(rvq
);
690 __napi_schedule(&rq
->napi
);
694 static void virtnet_napi_enable(struct receive_queue
*rq
)
696 napi_enable(&rq
->napi
);
698 /* If all buffers were filled by other side before we napi_enabled, we
699 * won't get another interrupt, so process any outstanding packets
700 * now. virtnet_poll wants re-enable the queue, so we disable here.
701 * We synchronize against interrupts via NAPI_STATE_SCHED */
702 if (napi_schedule_prep(&rq
->napi
)) {
703 virtqueue_disable_cb(rq
->vq
);
705 __napi_schedule(&rq
->napi
);
710 static void refill_work(struct work_struct
*work
)
712 struct virtnet_info
*vi
=
713 container_of(work
, struct virtnet_info
, refill
.work
);
717 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++) {
718 struct receive_queue
*rq
= &vi
->rq
[i
];
720 napi_disable(&rq
->napi
);
721 still_empty
= !try_fill_recv(vi
, rq
, GFP_KERNEL
);
722 virtnet_napi_enable(rq
);
724 /* In theory, this can happen: if we don't get any buffers in
725 * we will *never* try to fill again.
728 schedule_delayed_work(&vi
->refill
, HZ
/2);
732 static int virtnet_receive(struct receive_queue
*rq
, int budget
)
734 struct virtnet_info
*vi
= rq
->vq
->vdev
->priv
;
735 unsigned int len
, received
= 0;
738 while (received
< budget
&&
739 (buf
= virtqueue_get_buf(rq
->vq
, &len
)) != NULL
) {
740 receive_buf(vi
, rq
, buf
, len
);
744 if (rq
->vq
->num_free
> virtqueue_get_vring_size(rq
->vq
) / 2) {
745 if (!try_fill_recv(vi
, rq
, GFP_ATOMIC
))
746 schedule_delayed_work(&vi
->refill
, 0);
752 static int virtnet_poll(struct napi_struct
*napi
, int budget
)
754 struct receive_queue
*rq
=
755 container_of(napi
, struct receive_queue
, napi
);
756 unsigned int r
, received
;
758 received
= virtnet_receive(rq
, budget
);
760 /* Out of packets? */
761 if (received
< budget
) {
762 r
= virtqueue_enable_cb_prepare(rq
->vq
);
763 napi_complete_done(napi
, received
);
764 if (unlikely(virtqueue_poll(rq
->vq
, r
)) &&
765 napi_schedule_prep(napi
)) {
766 virtqueue_disable_cb(rq
->vq
);
767 __napi_schedule(napi
);
774 #ifdef CONFIG_NET_RX_BUSY_POLL
775 /* must be called with local_bh_disable()d */
776 static int virtnet_busy_poll(struct napi_struct
*napi
)
778 struct receive_queue
*rq
=
779 container_of(napi
, struct receive_queue
, napi
);
780 struct virtnet_info
*vi
= rq
->vq
->vdev
->priv
;
781 int r
, received
= 0, budget
= 4;
783 if (!(vi
->status
& VIRTIO_NET_S_LINK_UP
))
784 return LL_FLUSH_FAILED
;
786 if (!napi_schedule_prep(napi
))
787 return LL_FLUSH_BUSY
;
789 virtqueue_disable_cb(rq
->vq
);
792 received
+= virtnet_receive(rq
, budget
);
794 r
= virtqueue_enable_cb_prepare(rq
->vq
);
795 clear_bit(NAPI_STATE_SCHED
, &napi
->state
);
796 if (unlikely(virtqueue_poll(rq
->vq
, r
)) &&
797 napi_schedule_prep(napi
)) {
798 virtqueue_disable_cb(rq
->vq
);
799 if (received
< budget
) {
803 __napi_schedule(napi
);
809 #endif /* CONFIG_NET_RX_BUSY_POLL */
811 static int virtnet_open(struct net_device
*dev
)
813 struct virtnet_info
*vi
= netdev_priv(dev
);
816 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
817 if (i
< vi
->curr_queue_pairs
)
818 /* Make sure we have some buffers: if oom use wq. */
819 if (!try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
))
820 schedule_delayed_work(&vi
->refill
, 0);
821 virtnet_napi_enable(&vi
->rq
[i
]);
827 static void free_old_xmit_skbs(struct send_queue
*sq
)
831 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
832 struct virtnet_stats
*stats
= this_cpu_ptr(vi
->stats
);
834 while ((skb
= virtqueue_get_buf(sq
->vq
, &len
)) != NULL
) {
835 pr_debug("Sent skb %p\n", skb
);
837 u64_stats_update_begin(&stats
->tx_syncp
);
838 stats
->tx_bytes
+= skb
->len
;
840 u64_stats_update_end(&stats
->tx_syncp
);
842 dev_kfree_skb_any(skb
);
846 static int xmit_skb(struct send_queue
*sq
, struct sk_buff
*skb
)
848 struct virtio_net_hdr_mrg_rxbuf
*hdr
;
849 const unsigned char *dest
= ((struct ethhdr
*)skb
->data
)->h_dest
;
850 struct virtnet_info
*vi
= sq
->vq
->vdev
->priv
;
852 unsigned hdr_len
= vi
->hdr_len
;
855 pr_debug("%s: xmit %p %pM\n", vi
->dev
->name
, skb
, dest
);
857 can_push
= vi
->any_header_sg
&&
858 !((unsigned long)skb
->data
& (__alignof__(*hdr
) - 1)) &&
859 !skb_header_cloned(skb
) && skb_headroom(skb
) >= hdr_len
;
860 /* Even if we can, don't push here yet as this would skew
861 * csum_start offset below. */
863 hdr
= (struct virtio_net_hdr_mrg_rxbuf
*)(skb
->data
- hdr_len
);
865 hdr
= skb_vnet_hdr(skb
);
867 if (skb
->ip_summed
== CHECKSUM_PARTIAL
) {
868 hdr
->hdr
.flags
= VIRTIO_NET_HDR_F_NEEDS_CSUM
;
869 hdr
->hdr
.csum_start
= cpu_to_virtio16(vi
->vdev
,
870 skb_checksum_start_offset(skb
));
871 hdr
->hdr
.csum_offset
= cpu_to_virtio16(vi
->vdev
,
875 hdr
->hdr
.csum_offset
= hdr
->hdr
.csum_start
= 0;
878 if (skb_is_gso(skb
)) {
879 hdr
->hdr
.hdr_len
= cpu_to_virtio16(vi
->vdev
, skb_headlen(skb
));
880 hdr
->hdr
.gso_size
= cpu_to_virtio16(vi
->vdev
,
881 skb_shinfo(skb
)->gso_size
);
882 if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV4
)
883 hdr
->hdr
.gso_type
= VIRTIO_NET_HDR_GSO_TCPV4
;
884 else if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
)
885 hdr
->hdr
.gso_type
= VIRTIO_NET_HDR_GSO_TCPV6
;
886 else if (skb_shinfo(skb
)->gso_type
& SKB_GSO_UDP
)
887 hdr
->hdr
.gso_type
= VIRTIO_NET_HDR_GSO_UDP
;
890 if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCP_ECN
)
891 hdr
->hdr
.gso_type
|= VIRTIO_NET_HDR_GSO_ECN
;
893 hdr
->hdr
.gso_type
= VIRTIO_NET_HDR_GSO_NONE
;
894 hdr
->hdr
.gso_size
= hdr
->hdr
.hdr_len
= 0;
897 if (vi
->mergeable_rx_bufs
)
898 hdr
->num_buffers
= 0;
900 sg_init_table(sq
->sg
, skb_shinfo(skb
)->nr_frags
+ (can_push
? 1 : 2));
902 __skb_push(skb
, hdr_len
);
903 num_sg
= skb_to_sgvec(skb
, sq
->sg
, 0, skb
->len
);
904 /* Pull header back to avoid skew in tx bytes calculations. */
905 __skb_pull(skb
, hdr_len
);
907 sg_set_buf(sq
->sg
, hdr
, hdr_len
);
908 num_sg
= skb_to_sgvec(skb
, sq
->sg
+ 1, 0, skb
->len
) + 1;
910 return virtqueue_add_outbuf(sq
->vq
, sq
->sg
, num_sg
, skb
, GFP_ATOMIC
);
913 static netdev_tx_t
start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
915 struct virtnet_info
*vi
= netdev_priv(dev
);
916 int qnum
= skb_get_queue_mapping(skb
);
917 struct send_queue
*sq
= &vi
->sq
[qnum
];
919 struct netdev_queue
*txq
= netdev_get_tx_queue(dev
, qnum
);
920 bool kick
= !skb
->xmit_more
;
922 /* Free up any pending old buffers before queueing new ones. */
923 free_old_xmit_skbs(sq
);
925 /* timestamp packet in software */
926 skb_tx_timestamp(skb
);
928 /* Try to transmit */
929 err
= xmit_skb(sq
, skb
);
931 /* This should not happen! */
933 dev
->stats
.tx_fifo_errors
++;
936 "Unexpected TXQ (%d) queue failure: %d\n", qnum
, err
);
937 dev
->stats
.tx_dropped
++;
938 dev_kfree_skb_any(skb
);
942 /* Don't wait up for transmitted skbs to be freed. */
946 /* If running out of space, stop queue to avoid getting packets that we
947 * are then unable to transmit.
948 * An alternative would be to force queuing layer to requeue the skb by
949 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
950 * returned in a normal path of operation: it means that driver is not
951 * maintaining the TX queue stop/start state properly, and causes
952 * the stack to do a non-trivial amount of useless work.
953 * Since most packets only take 1 or 2 ring slots, stopping the queue
954 * early means 16 slots are typically wasted.
956 if (sq
->vq
->num_free
< 2+MAX_SKB_FRAGS
) {
957 netif_stop_subqueue(dev
, qnum
);
958 if (unlikely(!virtqueue_enable_cb_delayed(sq
->vq
))) {
959 /* More just got used, free them then recheck. */
960 free_old_xmit_skbs(sq
);
961 if (sq
->vq
->num_free
>= 2+MAX_SKB_FRAGS
) {
962 netif_start_subqueue(dev
, qnum
);
963 virtqueue_disable_cb(sq
->vq
);
968 if (kick
|| netif_xmit_stopped(txq
))
969 virtqueue_kick(sq
->vq
);
975 * Send command via the control virtqueue and check status. Commands
976 * supported by the hypervisor, as indicated by feature bits, should
977 * never fail unless improperly formatted.
979 static bool virtnet_send_command(struct virtnet_info
*vi
, u8
class, u8 cmd
,
980 struct scatterlist
*out
)
982 struct scatterlist
*sgs
[4], hdr
, stat
;
983 unsigned out_num
= 0, tmp
;
985 /* Caller should know better */
986 BUG_ON(!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VQ
));
988 vi
->ctrl_status
= ~0;
989 vi
->ctrl_hdr
.class = class;
990 vi
->ctrl_hdr
.cmd
= cmd
;
992 sg_init_one(&hdr
, &vi
->ctrl_hdr
, sizeof(vi
->ctrl_hdr
));
993 sgs
[out_num
++] = &hdr
;
996 sgs
[out_num
++] = out
;
998 /* Add return status. */
999 sg_init_one(&stat
, &vi
->ctrl_status
, sizeof(vi
->ctrl_status
));
1000 sgs
[out_num
] = &stat
;
1002 BUG_ON(out_num
+ 1 > ARRAY_SIZE(sgs
));
1003 virtqueue_add_sgs(vi
->cvq
, sgs
, out_num
, 1, vi
, GFP_ATOMIC
);
1005 if (unlikely(!virtqueue_kick(vi
->cvq
)))
1006 return vi
->ctrl_status
== VIRTIO_NET_OK
;
1008 /* Spin for a response, the kick causes an ioport write, trapping
1009 * into the hypervisor, so the request should be handled immediately.
1011 while (!virtqueue_get_buf(vi
->cvq
, &tmp
) &&
1012 !virtqueue_is_broken(vi
->cvq
))
1015 return vi
->ctrl_status
== VIRTIO_NET_OK
;
1018 static int virtnet_set_mac_address(struct net_device
*dev
, void *p
)
1020 struct virtnet_info
*vi
= netdev_priv(dev
);
1021 struct virtio_device
*vdev
= vi
->vdev
;
1023 struct sockaddr
*addr
= p
;
1024 struct scatterlist sg
;
1026 ret
= eth_prepare_mac_addr_change(dev
, p
);
1030 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_MAC_ADDR
)) {
1031 sg_init_one(&sg
, addr
->sa_data
, dev
->addr_len
);
1032 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MAC
,
1033 VIRTIO_NET_CTRL_MAC_ADDR_SET
, &sg
)) {
1034 dev_warn(&vdev
->dev
,
1035 "Failed to set mac address by vq command.\n");
1038 } else if (virtio_has_feature(vdev
, VIRTIO_NET_F_MAC
) &&
1039 !virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
)) {
1042 /* Naturally, this has an atomicity problem. */
1043 for (i
= 0; i
< dev
->addr_len
; i
++)
1044 virtio_cwrite8(vdev
,
1045 offsetof(struct virtio_net_config
, mac
) +
1046 i
, addr
->sa_data
[i
]);
1049 eth_commit_mac_addr_change(dev
, p
);
1054 static struct rtnl_link_stats64
*virtnet_stats(struct net_device
*dev
,
1055 struct rtnl_link_stats64
*tot
)
1057 struct virtnet_info
*vi
= netdev_priv(dev
);
1061 for_each_possible_cpu(cpu
) {
1062 struct virtnet_stats
*stats
= per_cpu_ptr(vi
->stats
, cpu
);
1063 u64 tpackets
, tbytes
, rpackets
, rbytes
;
1066 start
= u64_stats_fetch_begin_irq(&stats
->tx_syncp
);
1067 tpackets
= stats
->tx_packets
;
1068 tbytes
= stats
->tx_bytes
;
1069 } while (u64_stats_fetch_retry_irq(&stats
->tx_syncp
, start
));
1072 start
= u64_stats_fetch_begin_irq(&stats
->rx_syncp
);
1073 rpackets
= stats
->rx_packets
;
1074 rbytes
= stats
->rx_bytes
;
1075 } while (u64_stats_fetch_retry_irq(&stats
->rx_syncp
, start
));
1077 tot
->rx_packets
+= rpackets
;
1078 tot
->tx_packets
+= tpackets
;
1079 tot
->rx_bytes
+= rbytes
;
1080 tot
->tx_bytes
+= tbytes
;
1083 tot
->tx_dropped
= dev
->stats
.tx_dropped
;
1084 tot
->tx_fifo_errors
= dev
->stats
.tx_fifo_errors
;
1085 tot
->rx_dropped
= dev
->stats
.rx_dropped
;
1086 tot
->rx_length_errors
= dev
->stats
.rx_length_errors
;
1087 tot
->rx_frame_errors
= dev
->stats
.rx_frame_errors
;
1092 #ifdef CONFIG_NET_POLL_CONTROLLER
1093 static void virtnet_netpoll(struct net_device
*dev
)
1095 struct virtnet_info
*vi
= netdev_priv(dev
);
1098 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++)
1099 napi_schedule(&vi
->rq
[i
].napi
);
1103 static void virtnet_ack_link_announce(struct virtnet_info
*vi
)
1106 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_ANNOUNCE
,
1107 VIRTIO_NET_CTRL_ANNOUNCE_ACK
, NULL
))
1108 dev_warn(&vi
->dev
->dev
, "Failed to ack link announce.\n");
1112 static int virtnet_set_queues(struct virtnet_info
*vi
, u16 queue_pairs
)
1114 struct scatterlist sg
;
1115 struct virtio_net_ctrl_mq s
;
1116 struct net_device
*dev
= vi
->dev
;
1118 if (!vi
->has_cvq
|| !virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_MQ
))
1121 s
.virtqueue_pairs
= cpu_to_virtio16(vi
->vdev
, queue_pairs
);
1122 sg_init_one(&sg
, &s
, sizeof(s
));
1124 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MQ
,
1125 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET
, &sg
)) {
1126 dev_warn(&dev
->dev
, "Fail to set num of queue pairs to %d\n",
1130 vi
->curr_queue_pairs
= queue_pairs
;
1131 /* virtnet_open() will refill when device is going to up. */
1132 if (dev
->flags
& IFF_UP
)
1133 schedule_delayed_work(&vi
->refill
, 0);
1139 static int virtnet_close(struct net_device
*dev
)
1141 struct virtnet_info
*vi
= netdev_priv(dev
);
1144 /* Make sure refill_work doesn't re-enable napi! */
1145 cancel_delayed_work_sync(&vi
->refill
);
1147 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1148 napi_disable(&vi
->rq
[i
].napi
);
1153 static void virtnet_set_rx_mode(struct net_device
*dev
)
1155 struct virtnet_info
*vi
= netdev_priv(dev
);
1156 struct scatterlist sg
[2];
1157 struct virtio_net_ctrl_mac
*mac_data
;
1158 struct netdev_hw_addr
*ha
;
1164 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1165 if (!virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_RX
))
1168 vi
->ctrl_promisc
= ((dev
->flags
& IFF_PROMISC
) != 0);
1169 vi
->ctrl_allmulti
= ((dev
->flags
& IFF_ALLMULTI
) != 0);
1171 sg_init_one(sg
, &vi
->ctrl_promisc
, sizeof(vi
->ctrl_promisc
));
1173 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_RX
,
1174 VIRTIO_NET_CTRL_RX_PROMISC
, sg
))
1175 dev_warn(&dev
->dev
, "Failed to %sable promisc mode.\n",
1176 vi
->ctrl_promisc
? "en" : "dis");
1178 sg_init_one(sg
, &vi
->ctrl_allmulti
, sizeof(vi
->ctrl_allmulti
));
1180 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_RX
,
1181 VIRTIO_NET_CTRL_RX_ALLMULTI
, sg
))
1182 dev_warn(&dev
->dev
, "Failed to %sable allmulti mode.\n",
1183 vi
->ctrl_allmulti
? "en" : "dis");
1185 uc_count
= netdev_uc_count(dev
);
1186 mc_count
= netdev_mc_count(dev
);
1187 /* MAC filter - use one buffer for both lists */
1188 buf
= kzalloc(((uc_count
+ mc_count
) * ETH_ALEN
) +
1189 (2 * sizeof(mac_data
->entries
)), GFP_ATOMIC
);
1194 sg_init_table(sg
, 2);
1196 /* Store the unicast list and count in the front of the buffer */
1197 mac_data
->entries
= cpu_to_virtio32(vi
->vdev
, uc_count
);
1199 netdev_for_each_uc_addr(ha
, dev
)
1200 memcpy(&mac_data
->macs
[i
++][0], ha
->addr
, ETH_ALEN
);
1202 sg_set_buf(&sg
[0], mac_data
,
1203 sizeof(mac_data
->entries
) + (uc_count
* ETH_ALEN
));
1205 /* multicast list and count fill the end */
1206 mac_data
= (void *)&mac_data
->macs
[uc_count
][0];
1208 mac_data
->entries
= cpu_to_virtio32(vi
->vdev
, mc_count
);
1210 netdev_for_each_mc_addr(ha
, dev
)
1211 memcpy(&mac_data
->macs
[i
++][0], ha
->addr
, ETH_ALEN
);
1213 sg_set_buf(&sg
[1], mac_data
,
1214 sizeof(mac_data
->entries
) + (mc_count
* ETH_ALEN
));
1216 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_MAC
,
1217 VIRTIO_NET_CTRL_MAC_TABLE_SET
, sg
))
1218 dev_warn(&dev
->dev
, "Failed to set MAC filter table.\n");
1223 static int virtnet_vlan_rx_add_vid(struct net_device
*dev
,
1224 __be16 proto
, u16 vid
)
1226 struct virtnet_info
*vi
= netdev_priv(dev
);
1227 struct scatterlist sg
;
1229 sg_init_one(&sg
, &vid
, sizeof(vid
));
1231 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_VLAN
,
1232 VIRTIO_NET_CTRL_VLAN_ADD
, &sg
))
1233 dev_warn(&dev
->dev
, "Failed to add VLAN ID %d.\n", vid
);
1237 static int virtnet_vlan_rx_kill_vid(struct net_device
*dev
,
1238 __be16 proto
, u16 vid
)
1240 struct virtnet_info
*vi
= netdev_priv(dev
);
1241 struct scatterlist sg
;
1243 sg_init_one(&sg
, &vid
, sizeof(vid
));
1245 if (!virtnet_send_command(vi
, VIRTIO_NET_CTRL_VLAN
,
1246 VIRTIO_NET_CTRL_VLAN_DEL
, &sg
))
1247 dev_warn(&dev
->dev
, "Failed to kill VLAN ID %d.\n", vid
);
1251 static void virtnet_clean_affinity(struct virtnet_info
*vi
, long hcpu
)
1255 if (vi
->affinity_hint_set
) {
1256 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1257 virtqueue_set_affinity(vi
->rq
[i
].vq
, -1);
1258 virtqueue_set_affinity(vi
->sq
[i
].vq
, -1);
1261 vi
->affinity_hint_set
= false;
1265 static void virtnet_set_affinity(struct virtnet_info
*vi
)
1270 /* In multiqueue mode, when the number of cpu is equal to the number of
1271 * queue pairs, we let the queue pairs to be private to one cpu by
1272 * setting the affinity hint to eliminate the contention.
1274 if (vi
->curr_queue_pairs
== 1 ||
1275 vi
->max_queue_pairs
!= num_online_cpus()) {
1276 virtnet_clean_affinity(vi
, -1);
1281 for_each_online_cpu(cpu
) {
1282 virtqueue_set_affinity(vi
->rq
[i
].vq
, cpu
);
1283 virtqueue_set_affinity(vi
->sq
[i
].vq
, cpu
);
1284 netif_set_xps_queue(vi
->dev
, cpumask_of(cpu
), i
);
1288 vi
->affinity_hint_set
= true;
1291 static int virtnet_cpu_callback(struct notifier_block
*nfb
,
1292 unsigned long action
, void *hcpu
)
1294 struct virtnet_info
*vi
= container_of(nfb
, struct virtnet_info
, nb
);
1296 switch(action
& ~CPU_TASKS_FROZEN
) {
1298 case CPU_DOWN_FAILED
:
1300 virtnet_set_affinity(vi
);
1302 case CPU_DOWN_PREPARE
:
1303 virtnet_clean_affinity(vi
, (long)hcpu
);
1312 static void virtnet_get_ringparam(struct net_device
*dev
,
1313 struct ethtool_ringparam
*ring
)
1315 struct virtnet_info
*vi
= netdev_priv(dev
);
1317 ring
->rx_max_pending
= virtqueue_get_vring_size(vi
->rq
[0].vq
);
1318 ring
->tx_max_pending
= virtqueue_get_vring_size(vi
->sq
[0].vq
);
1319 ring
->rx_pending
= ring
->rx_max_pending
;
1320 ring
->tx_pending
= ring
->tx_max_pending
;
1324 static void virtnet_get_drvinfo(struct net_device
*dev
,
1325 struct ethtool_drvinfo
*info
)
1327 struct virtnet_info
*vi
= netdev_priv(dev
);
1328 struct virtio_device
*vdev
= vi
->vdev
;
1330 strlcpy(info
->driver
, KBUILD_MODNAME
, sizeof(info
->driver
));
1331 strlcpy(info
->version
, VIRTNET_DRIVER_VERSION
, sizeof(info
->version
));
1332 strlcpy(info
->bus_info
, virtio_bus_name(vdev
), sizeof(info
->bus_info
));
1336 /* TODO: Eliminate OOO packets during switching */
1337 static int virtnet_set_channels(struct net_device
*dev
,
1338 struct ethtool_channels
*channels
)
1340 struct virtnet_info
*vi
= netdev_priv(dev
);
1341 u16 queue_pairs
= channels
->combined_count
;
1344 /* We don't support separate rx/tx channels.
1345 * We don't allow setting 'other' channels.
1347 if (channels
->rx_count
|| channels
->tx_count
|| channels
->other_count
)
1350 if (queue_pairs
> vi
->max_queue_pairs
|| queue_pairs
== 0)
1354 err
= virtnet_set_queues(vi
, queue_pairs
);
1356 netif_set_real_num_tx_queues(dev
, queue_pairs
);
1357 netif_set_real_num_rx_queues(dev
, queue_pairs
);
1359 virtnet_set_affinity(vi
);
1366 static void virtnet_get_channels(struct net_device
*dev
,
1367 struct ethtool_channels
*channels
)
1369 struct virtnet_info
*vi
= netdev_priv(dev
);
1371 channels
->combined_count
= vi
->curr_queue_pairs
;
1372 channels
->max_combined
= vi
->max_queue_pairs
;
1373 channels
->max_other
= 0;
1374 channels
->rx_count
= 0;
1375 channels
->tx_count
= 0;
1376 channels
->other_count
= 0;
1379 static const struct ethtool_ops virtnet_ethtool_ops
= {
1380 .get_drvinfo
= virtnet_get_drvinfo
,
1381 .get_link
= ethtool_op_get_link
,
1382 .get_ringparam
= virtnet_get_ringparam
,
1383 .set_channels
= virtnet_set_channels
,
1384 .get_channels
= virtnet_get_channels
,
1385 .get_ts_info
= ethtool_op_get_ts_info
,
1389 #define MAX_MTU 65535
1391 static int virtnet_change_mtu(struct net_device
*dev
, int new_mtu
)
1393 if (new_mtu
< MIN_MTU
|| new_mtu
> MAX_MTU
)
1399 static const struct net_device_ops virtnet_netdev
= {
1400 .ndo_open
= virtnet_open
,
1401 .ndo_stop
= virtnet_close
,
1402 .ndo_start_xmit
= start_xmit
,
1403 .ndo_validate_addr
= eth_validate_addr
,
1404 .ndo_set_mac_address
= virtnet_set_mac_address
,
1405 .ndo_set_rx_mode
= virtnet_set_rx_mode
,
1406 .ndo_change_mtu
= virtnet_change_mtu
,
1407 .ndo_get_stats64
= virtnet_stats
,
1408 .ndo_vlan_rx_add_vid
= virtnet_vlan_rx_add_vid
,
1409 .ndo_vlan_rx_kill_vid
= virtnet_vlan_rx_kill_vid
,
1410 #ifdef CONFIG_NET_POLL_CONTROLLER
1411 .ndo_poll_controller
= virtnet_netpoll
,
1413 #ifdef CONFIG_NET_RX_BUSY_POLL
1414 .ndo_busy_poll
= virtnet_busy_poll
,
1418 static void virtnet_config_changed_work(struct work_struct
*work
)
1420 struct virtnet_info
*vi
=
1421 container_of(work
, struct virtnet_info
, config_work
);
1424 if (virtio_cread_feature(vi
->vdev
, VIRTIO_NET_F_STATUS
,
1425 struct virtio_net_config
, status
, &v
) < 0)
1428 if (v
& VIRTIO_NET_S_ANNOUNCE
) {
1429 netdev_notify_peers(vi
->dev
);
1430 virtnet_ack_link_announce(vi
);
1433 /* Ignore unknown (future) status bits */
1434 v
&= VIRTIO_NET_S_LINK_UP
;
1436 if (vi
->status
== v
)
1441 if (vi
->status
& VIRTIO_NET_S_LINK_UP
) {
1442 netif_carrier_on(vi
->dev
);
1443 netif_tx_wake_all_queues(vi
->dev
);
1445 netif_carrier_off(vi
->dev
);
1446 netif_tx_stop_all_queues(vi
->dev
);
1450 static void virtnet_config_changed(struct virtio_device
*vdev
)
1452 struct virtnet_info
*vi
= vdev
->priv
;
1454 schedule_work(&vi
->config_work
);
1457 static void virtnet_free_queues(struct virtnet_info
*vi
)
1461 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1462 napi_hash_del(&vi
->rq
[i
].napi
);
1463 netif_napi_del(&vi
->rq
[i
].napi
);
1470 static void free_receive_bufs(struct virtnet_info
*vi
)
1474 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1475 while (vi
->rq
[i
].pages
)
1476 __free_pages(get_a_page(&vi
->rq
[i
], GFP_KERNEL
), 0);
1480 static void free_receive_page_frags(struct virtnet_info
*vi
)
1483 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1484 if (vi
->rq
[i
].alloc_frag
.page
)
1485 put_page(vi
->rq
[i
].alloc_frag
.page
);
1488 static void free_unused_bufs(struct virtnet_info
*vi
)
1493 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1494 struct virtqueue
*vq
= vi
->sq
[i
].vq
;
1495 while ((buf
= virtqueue_detach_unused_buf(vq
)) != NULL
)
1499 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1500 struct virtqueue
*vq
= vi
->rq
[i
].vq
;
1502 while ((buf
= virtqueue_detach_unused_buf(vq
)) != NULL
) {
1503 if (vi
->mergeable_rx_bufs
) {
1504 unsigned long ctx
= (unsigned long)buf
;
1505 void *base
= mergeable_ctx_to_buf_address(ctx
);
1506 put_page(virt_to_head_page(base
));
1507 } else if (vi
->big_packets
) {
1508 give_pages(&vi
->rq
[i
], buf
);
1516 static void virtnet_del_vqs(struct virtnet_info
*vi
)
1518 struct virtio_device
*vdev
= vi
->vdev
;
1520 virtnet_clean_affinity(vi
, -1);
1522 vdev
->config
->del_vqs(vdev
);
1524 virtnet_free_queues(vi
);
1527 static int virtnet_find_vqs(struct virtnet_info
*vi
)
1529 vq_callback_t
**callbacks
;
1530 struct virtqueue
**vqs
;
1535 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
1536 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
1537 * possible control vq.
1539 total_vqs
= vi
->max_queue_pairs
* 2 +
1540 virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VQ
);
1542 /* Allocate space for find_vqs parameters */
1543 vqs
= kzalloc(total_vqs
* sizeof(*vqs
), GFP_KERNEL
);
1546 callbacks
= kmalloc(total_vqs
* sizeof(*callbacks
), GFP_KERNEL
);
1549 names
= kmalloc(total_vqs
* sizeof(*names
), GFP_KERNEL
);
1553 /* Parameters for control virtqueue, if any */
1555 callbacks
[total_vqs
- 1] = NULL
;
1556 names
[total_vqs
- 1] = "control";
1559 /* Allocate/initialize parameters for send/receive virtqueues */
1560 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1561 callbacks
[rxq2vq(i
)] = skb_recv_done
;
1562 callbacks
[txq2vq(i
)] = skb_xmit_done
;
1563 sprintf(vi
->rq
[i
].name
, "input.%d", i
);
1564 sprintf(vi
->sq
[i
].name
, "output.%d", i
);
1565 names
[rxq2vq(i
)] = vi
->rq
[i
].name
;
1566 names
[txq2vq(i
)] = vi
->sq
[i
].name
;
1569 ret
= vi
->vdev
->config
->find_vqs(vi
->vdev
, total_vqs
, vqs
, callbacks
,
1575 vi
->cvq
= vqs
[total_vqs
- 1];
1576 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_CTRL_VLAN
))
1577 vi
->dev
->features
|= NETIF_F_HW_VLAN_CTAG_FILTER
;
1580 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1581 vi
->rq
[i
].vq
= vqs
[rxq2vq(i
)];
1582 vi
->sq
[i
].vq
= vqs
[txq2vq(i
)];
1601 static int virtnet_alloc_queues(struct virtnet_info
*vi
)
1605 vi
->sq
= kzalloc(sizeof(*vi
->sq
) * vi
->max_queue_pairs
, GFP_KERNEL
);
1608 vi
->rq
= kzalloc(sizeof(*vi
->rq
) * vi
->max_queue_pairs
, GFP_KERNEL
);
1612 INIT_DELAYED_WORK(&vi
->refill
, refill_work
);
1613 for (i
= 0; i
< vi
->max_queue_pairs
; i
++) {
1614 vi
->rq
[i
].pages
= NULL
;
1615 netif_napi_add(vi
->dev
, &vi
->rq
[i
].napi
, virtnet_poll
,
1618 sg_init_table(vi
->rq
[i
].sg
, ARRAY_SIZE(vi
->rq
[i
].sg
));
1619 ewma_pkt_len_init(&vi
->rq
[i
].mrg_avg_pkt_len
);
1620 sg_init_table(vi
->sq
[i
].sg
, ARRAY_SIZE(vi
->sq
[i
].sg
));
1631 static int init_vqs(struct virtnet_info
*vi
)
1635 /* Allocate send & receive queues */
1636 ret
= virtnet_alloc_queues(vi
);
1640 ret
= virtnet_find_vqs(vi
);
1645 virtnet_set_affinity(vi
);
1651 virtnet_free_queues(vi
);
1657 static ssize_t
mergeable_rx_buffer_size_show(struct netdev_rx_queue
*queue
,
1658 struct rx_queue_attribute
*attribute
, char *buf
)
1660 struct virtnet_info
*vi
= netdev_priv(queue
->dev
);
1661 unsigned int queue_index
= get_netdev_rx_queue_index(queue
);
1662 struct ewma_pkt_len
*avg
;
1664 BUG_ON(queue_index
>= vi
->max_queue_pairs
);
1665 avg
= &vi
->rq
[queue_index
].mrg_avg_pkt_len
;
1666 return sprintf(buf
, "%u\n", get_mergeable_buf_len(avg
));
1669 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute
=
1670 __ATTR_RO(mergeable_rx_buffer_size
);
1672 static struct attribute
*virtio_net_mrg_rx_attrs
[] = {
1673 &mergeable_rx_buffer_size_attribute
.attr
,
1677 static const struct attribute_group virtio_net_mrg_rx_group
= {
1678 .name
= "virtio_net",
1679 .attrs
= virtio_net_mrg_rx_attrs
1683 static bool virtnet_fail_on_feature(struct virtio_device
*vdev
,
1685 const char *fname
, const char *dname
)
1687 if (!virtio_has_feature(vdev
, fbit
))
1690 dev_err(&vdev
->dev
, "device advertises feature %s but not %s",
1696 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
1697 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
1699 static bool virtnet_validate_features(struct virtio_device
*vdev
)
1701 if (!virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
) &&
1702 (VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_RX
,
1703 "VIRTIO_NET_F_CTRL_VQ") ||
1704 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_VLAN
,
1705 "VIRTIO_NET_F_CTRL_VQ") ||
1706 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_GUEST_ANNOUNCE
,
1707 "VIRTIO_NET_F_CTRL_VQ") ||
1708 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_MQ
, "VIRTIO_NET_F_CTRL_VQ") ||
1709 VIRTNET_FAIL_ON(vdev
, VIRTIO_NET_F_CTRL_MAC_ADDR
,
1710 "VIRTIO_NET_F_CTRL_VQ"))) {
1717 static int virtnet_probe(struct virtio_device
*vdev
)
1720 struct net_device
*dev
;
1721 struct virtnet_info
*vi
;
1722 u16 max_queue_pairs
;
1724 if (!vdev
->config
->get
) {
1725 dev_err(&vdev
->dev
, "%s failure: config access disabled\n",
1730 if (!virtnet_validate_features(vdev
))
1733 /* Find if host supports multiqueue virtio_net device */
1734 err
= virtio_cread_feature(vdev
, VIRTIO_NET_F_MQ
,
1735 struct virtio_net_config
,
1736 max_virtqueue_pairs
, &max_queue_pairs
);
1738 /* We need at least 2 queue's */
1739 if (err
|| max_queue_pairs
< VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN
||
1740 max_queue_pairs
> VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX
||
1741 !virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
))
1742 max_queue_pairs
= 1;
1744 /* Allocate ourselves a network device with room for our info */
1745 dev
= alloc_etherdev_mq(sizeof(struct virtnet_info
), max_queue_pairs
);
1749 /* Set up network device as normal. */
1750 dev
->priv_flags
|= IFF_UNICAST_FLT
| IFF_LIVE_ADDR_CHANGE
;
1751 dev
->netdev_ops
= &virtnet_netdev
;
1752 dev
->features
= NETIF_F_HIGHDMA
;
1754 dev
->ethtool_ops
= &virtnet_ethtool_ops
;
1755 SET_NETDEV_DEV(dev
, &vdev
->dev
);
1757 /* Do we support "hardware" checksums? */
1758 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CSUM
)) {
1759 /* This opens up the world of extra features. */
1760 dev
->hw_features
|= NETIF_F_HW_CSUM
| NETIF_F_SG
;
1762 dev
->features
|= NETIF_F_HW_CSUM
| NETIF_F_SG
;
1764 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GSO
)) {
1765 dev
->hw_features
|= NETIF_F_TSO
| NETIF_F_UFO
1766 | NETIF_F_TSO_ECN
| NETIF_F_TSO6
;
1768 /* Individual feature bits: what can host handle? */
1769 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_TSO4
))
1770 dev
->hw_features
|= NETIF_F_TSO
;
1771 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_TSO6
))
1772 dev
->hw_features
|= NETIF_F_TSO6
;
1773 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_ECN
))
1774 dev
->hw_features
|= NETIF_F_TSO_ECN
;
1775 if (virtio_has_feature(vdev
, VIRTIO_NET_F_HOST_UFO
))
1776 dev
->hw_features
|= NETIF_F_UFO
;
1778 dev
->features
|= NETIF_F_GSO_ROBUST
;
1781 dev
->features
|= dev
->hw_features
& (NETIF_F_ALL_TSO
|NETIF_F_UFO
);
1782 /* (!csum && gso) case will be fixed by register_netdev() */
1784 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_CSUM
))
1785 dev
->features
|= NETIF_F_RXCSUM
;
1787 dev
->vlan_features
= dev
->features
;
1789 /* Configuration may specify what MAC to use. Otherwise random. */
1790 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MAC
))
1791 virtio_cread_bytes(vdev
,
1792 offsetof(struct virtio_net_config
, mac
),
1793 dev
->dev_addr
, dev
->addr_len
);
1795 eth_hw_addr_random(dev
);
1797 /* Set up our device-specific information */
1798 vi
= netdev_priv(dev
);
1802 vi
->stats
= alloc_percpu(struct virtnet_stats
);
1804 if (vi
->stats
== NULL
)
1807 for_each_possible_cpu(i
) {
1808 struct virtnet_stats
*virtnet_stats
;
1809 virtnet_stats
= per_cpu_ptr(vi
->stats
, i
);
1810 u64_stats_init(&virtnet_stats
->tx_syncp
);
1811 u64_stats_init(&virtnet_stats
->rx_syncp
);
1814 INIT_WORK(&vi
->config_work
, virtnet_config_changed_work
);
1816 /* If we can receive ANY GSO packets, we must allocate large ones. */
1817 if (virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_TSO4
) ||
1818 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_TSO6
) ||
1819 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_ECN
) ||
1820 virtio_has_feature(vdev
, VIRTIO_NET_F_GUEST_UFO
))
1821 vi
->big_packets
= true;
1823 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MRG_RXBUF
))
1824 vi
->mergeable_rx_bufs
= true;
1826 if (virtio_has_feature(vdev
, VIRTIO_NET_F_MRG_RXBUF
) ||
1827 virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
))
1828 vi
->hdr_len
= sizeof(struct virtio_net_hdr_mrg_rxbuf
);
1830 vi
->hdr_len
= sizeof(struct virtio_net_hdr
);
1832 if (virtio_has_feature(vdev
, VIRTIO_F_ANY_LAYOUT
) ||
1833 virtio_has_feature(vdev
, VIRTIO_F_VERSION_1
))
1834 vi
->any_header_sg
= true;
1836 if (virtio_has_feature(vdev
, VIRTIO_NET_F_CTRL_VQ
))
1839 if (vi
->any_header_sg
)
1840 dev
->needed_headroom
= vi
->hdr_len
;
1842 /* Use single tx/rx queue pair as default */
1843 vi
->curr_queue_pairs
= 1;
1844 vi
->max_queue_pairs
= max_queue_pairs
;
1846 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
1852 if (vi
->mergeable_rx_bufs
)
1853 dev
->sysfs_rx_queue_group
= &virtio_net_mrg_rx_group
;
1855 netif_set_real_num_tx_queues(dev
, vi
->curr_queue_pairs
);
1856 netif_set_real_num_rx_queues(dev
, vi
->curr_queue_pairs
);
1858 err
= register_netdev(dev
);
1860 pr_debug("virtio_net: registering device failed\n");
1864 virtio_device_ready(vdev
);
1866 /* Last of all, set up some receive buffers. */
1867 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++) {
1868 try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
);
1870 /* If we didn't even get one input buffer, we're useless. */
1871 if (vi
->rq
[i
].vq
->num_free
==
1872 virtqueue_get_vring_size(vi
->rq
[i
].vq
)) {
1873 free_unused_bufs(vi
);
1875 goto free_recv_bufs
;
1879 vi
->nb
.notifier_call
= &virtnet_cpu_callback
;
1880 err
= register_hotcpu_notifier(&vi
->nb
);
1882 pr_debug("virtio_net: registering cpu notifier failed\n");
1883 goto free_recv_bufs
;
1886 /* Assume link up if device can't report link status,
1887 otherwise get link status from config. */
1888 if (virtio_has_feature(vi
->vdev
, VIRTIO_NET_F_STATUS
)) {
1889 netif_carrier_off(dev
);
1890 schedule_work(&vi
->config_work
);
1892 vi
->status
= VIRTIO_NET_S_LINK_UP
;
1893 netif_carrier_on(dev
);
1896 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
1897 dev
->name
, max_queue_pairs
);
1902 vi
->vdev
->config
->reset(vdev
);
1904 free_receive_bufs(vi
);
1905 unregister_netdev(dev
);
1907 cancel_delayed_work_sync(&vi
->refill
);
1908 free_receive_page_frags(vi
);
1909 virtnet_del_vqs(vi
);
1911 free_percpu(vi
->stats
);
1917 static void remove_vq_common(struct virtnet_info
*vi
)
1919 vi
->vdev
->config
->reset(vi
->vdev
);
1921 /* Free unused buffers in both send and recv, if any. */
1922 free_unused_bufs(vi
);
1924 free_receive_bufs(vi
);
1926 free_receive_page_frags(vi
);
1928 virtnet_del_vqs(vi
);
1931 static void virtnet_remove(struct virtio_device
*vdev
)
1933 struct virtnet_info
*vi
= vdev
->priv
;
1935 unregister_hotcpu_notifier(&vi
->nb
);
1937 /* Make sure no work handler is accessing the device. */
1938 flush_work(&vi
->config_work
);
1940 unregister_netdev(vi
->dev
);
1942 remove_vq_common(vi
);
1944 free_percpu(vi
->stats
);
1945 free_netdev(vi
->dev
);
1948 #ifdef CONFIG_PM_SLEEP
1949 static int virtnet_freeze(struct virtio_device
*vdev
)
1951 struct virtnet_info
*vi
= vdev
->priv
;
1954 unregister_hotcpu_notifier(&vi
->nb
);
1956 /* Make sure no work handler is accessing the device */
1957 flush_work(&vi
->config_work
);
1959 netif_device_detach(vi
->dev
);
1960 cancel_delayed_work_sync(&vi
->refill
);
1962 if (netif_running(vi
->dev
)) {
1963 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1964 napi_disable(&vi
->rq
[i
].napi
);
1967 remove_vq_common(vi
);
1972 static int virtnet_restore(struct virtio_device
*vdev
)
1974 struct virtnet_info
*vi
= vdev
->priv
;
1981 virtio_device_ready(vdev
);
1983 if (netif_running(vi
->dev
)) {
1984 for (i
= 0; i
< vi
->curr_queue_pairs
; i
++)
1985 if (!try_fill_recv(vi
, &vi
->rq
[i
], GFP_KERNEL
))
1986 schedule_delayed_work(&vi
->refill
, 0);
1988 for (i
= 0; i
< vi
->max_queue_pairs
; i
++)
1989 virtnet_napi_enable(&vi
->rq
[i
]);
1992 netif_device_attach(vi
->dev
);
1995 virtnet_set_queues(vi
, vi
->curr_queue_pairs
);
1998 err
= register_hotcpu_notifier(&vi
->nb
);
2006 static struct virtio_device_id id_table
[] = {
2007 { VIRTIO_ID_NET
, VIRTIO_DEV_ANY_ID
},
2011 static unsigned int features
[] = {
2012 VIRTIO_NET_F_CSUM
, VIRTIO_NET_F_GUEST_CSUM
,
2013 VIRTIO_NET_F_GSO
, VIRTIO_NET_F_MAC
,
2014 VIRTIO_NET_F_HOST_TSO4
, VIRTIO_NET_F_HOST_UFO
, VIRTIO_NET_F_HOST_TSO6
,
2015 VIRTIO_NET_F_HOST_ECN
, VIRTIO_NET_F_GUEST_TSO4
, VIRTIO_NET_F_GUEST_TSO6
,
2016 VIRTIO_NET_F_GUEST_ECN
, VIRTIO_NET_F_GUEST_UFO
,
2017 VIRTIO_NET_F_MRG_RXBUF
, VIRTIO_NET_F_STATUS
, VIRTIO_NET_F_CTRL_VQ
,
2018 VIRTIO_NET_F_CTRL_RX
, VIRTIO_NET_F_CTRL_VLAN
,
2019 VIRTIO_NET_F_GUEST_ANNOUNCE
, VIRTIO_NET_F_MQ
,
2020 VIRTIO_NET_F_CTRL_MAC_ADDR
,
2021 VIRTIO_F_ANY_LAYOUT
,
2024 static struct virtio_driver virtio_net_driver
= {
2025 .feature_table
= features
,
2026 .feature_table_size
= ARRAY_SIZE(features
),
2027 .driver
.name
= KBUILD_MODNAME
,
2028 .driver
.owner
= THIS_MODULE
,
2029 .id_table
= id_table
,
2030 .probe
= virtnet_probe
,
2031 .remove
= virtnet_remove
,
2032 .config_changed
= virtnet_config_changed
,
2033 #ifdef CONFIG_PM_SLEEP
2034 .freeze
= virtnet_freeze
,
2035 .restore
= virtnet_restore
,
2039 module_virtio_driver(virtio_net_driver
);
2041 MODULE_DEVICE_TABLE(virtio
, id_table
);
2042 MODULE_DESCRIPTION("Virtio network driver");
2043 MODULE_LICENSE("GPL");