net/sched: act_police: add missing spinlock initialization
[sfrench/cifs-2.6.git] / drivers / net / virtio_net.c
1 /* A network driver using virtio.
2  *
3  * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
4  *
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.
9  *
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.
14  *
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/>.
17  */
18 //#define DEBUG
19 #include <linux/netdevice.h>
20 #include <linux/etherdevice.h>
21 #include <linux/ethtool.h>
22 #include <linux/module.h>
23 #include <linux/virtio.h>
24 #include <linux/virtio_net.h>
25 #include <linux/bpf.h>
26 #include <linux/bpf_trace.h>
27 #include <linux/scatterlist.h>
28 #include <linux/if_vlan.h>
29 #include <linux/slab.h>
30 #include <linux/cpu.h>
31 #include <linux/average.h>
32 #include <linux/filter.h>
33 #include <linux/kernel.h>
34 #include <linux/pci.h>
35 #include <net/route.h>
36 #include <net/xdp.h>
37 #include <net/net_failover.h>
38
39 static int napi_weight = NAPI_POLL_WEIGHT;
40 module_param(napi_weight, int, 0444);
41
42 static bool csum = true, gso = true, napi_tx;
43 module_param(csum, bool, 0444);
44 module_param(gso, bool, 0444);
45 module_param(napi_tx, bool, 0644);
46
47 /* FIXME: MTU in config. */
48 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
49 #define GOOD_COPY_LEN   128
50
51 #define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
52
53 /* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
54 #define VIRTIO_XDP_HEADROOM 256
55
56 /* Separating two types of XDP xmit */
57 #define VIRTIO_XDP_TX           BIT(0)
58 #define VIRTIO_XDP_REDIR        BIT(1)
59
60 /* RX packet size EWMA. The average packet size is used to determine the packet
61  * buffer size when refilling RX rings. As the entire RX ring may be refilled
62  * at once, the weight is chosen so that the EWMA will be insensitive to short-
63  * term, transient changes in packet size.
64  */
65 DECLARE_EWMA(pkt_len, 0, 64)
66
67 #define VIRTNET_DRIVER_VERSION "1.0.0"
68
69 static const unsigned long guest_offloads[] = {
70         VIRTIO_NET_F_GUEST_TSO4,
71         VIRTIO_NET_F_GUEST_TSO6,
72         VIRTIO_NET_F_GUEST_ECN,
73         VIRTIO_NET_F_GUEST_UFO
74 };
75
76 struct virtnet_stat_desc {
77         char desc[ETH_GSTRING_LEN];
78         size_t offset;
79 };
80
81 struct virtnet_sq_stats {
82         struct u64_stats_sync syncp;
83         u64 packets;
84         u64 bytes;
85         u64 xdp_tx;
86         u64 xdp_tx_drops;
87         u64 kicks;
88 };
89
90 struct virtnet_rq_stats {
91         struct u64_stats_sync syncp;
92         u64 packets;
93         u64 bytes;
94         u64 drops;
95         u64 xdp_packets;
96         u64 xdp_tx;
97         u64 xdp_redirects;
98         u64 xdp_drops;
99         u64 kicks;
100 };
101
102 #define VIRTNET_SQ_STAT(m)      offsetof(struct virtnet_sq_stats, m)
103 #define VIRTNET_RQ_STAT(m)      offsetof(struct virtnet_rq_stats, m)
104
105 static const struct virtnet_stat_desc virtnet_sq_stats_desc[] = {
106         { "packets",            VIRTNET_SQ_STAT(packets) },
107         { "bytes",              VIRTNET_SQ_STAT(bytes) },
108         { "xdp_tx",             VIRTNET_SQ_STAT(xdp_tx) },
109         { "xdp_tx_drops",       VIRTNET_SQ_STAT(xdp_tx_drops) },
110         { "kicks",              VIRTNET_SQ_STAT(kicks) },
111 };
112
113 static const struct virtnet_stat_desc virtnet_rq_stats_desc[] = {
114         { "packets",            VIRTNET_RQ_STAT(packets) },
115         { "bytes",              VIRTNET_RQ_STAT(bytes) },
116         { "drops",              VIRTNET_RQ_STAT(drops) },
117         { "xdp_packets",        VIRTNET_RQ_STAT(xdp_packets) },
118         { "xdp_tx",             VIRTNET_RQ_STAT(xdp_tx) },
119         { "xdp_redirects",      VIRTNET_RQ_STAT(xdp_redirects) },
120         { "xdp_drops",          VIRTNET_RQ_STAT(xdp_drops) },
121         { "kicks",              VIRTNET_RQ_STAT(kicks) },
122 };
123
124 #define VIRTNET_SQ_STATS_LEN    ARRAY_SIZE(virtnet_sq_stats_desc)
125 #define VIRTNET_RQ_STATS_LEN    ARRAY_SIZE(virtnet_rq_stats_desc)
126
127 /* Internal representation of a send virtqueue */
128 struct send_queue {
129         /* Virtqueue associated with this send _queue */
130         struct virtqueue *vq;
131
132         /* TX: fragments + linear part + virtio header */
133         struct scatterlist sg[MAX_SKB_FRAGS + 2];
134
135         /* Name of the send queue: output.$index */
136         char name[40];
137
138         struct virtnet_sq_stats stats;
139
140         struct napi_struct napi;
141 };
142
143 /* Internal representation of a receive virtqueue */
144 struct receive_queue {
145         /* Virtqueue associated with this receive_queue */
146         struct virtqueue *vq;
147
148         struct napi_struct napi;
149
150         struct bpf_prog __rcu *xdp_prog;
151
152         struct virtnet_rq_stats stats;
153
154         /* Chain pages by the private ptr. */
155         struct page *pages;
156
157         /* Average packet length for mergeable receive buffers. */
158         struct ewma_pkt_len mrg_avg_pkt_len;
159
160         /* Page frag for packet buffer allocation. */
161         struct page_frag alloc_frag;
162
163         /* RX: fragments + linear part + virtio header */
164         struct scatterlist sg[MAX_SKB_FRAGS + 2];
165
166         /* Min single buffer size for mergeable buffers case. */
167         unsigned int min_buf_len;
168
169         /* Name of this receive queue: input.$index */
170         char name[40];
171
172         struct xdp_rxq_info xdp_rxq;
173 };
174
175 /* Control VQ buffers: protected by the rtnl lock */
176 struct control_buf {
177         struct virtio_net_ctrl_hdr hdr;
178         virtio_net_ctrl_ack status;
179         struct virtio_net_ctrl_mq mq;
180         u8 promisc;
181         u8 allmulti;
182         __virtio16 vid;
183         __virtio64 offloads;
184 };
185
186 struct virtnet_info {
187         struct virtio_device *vdev;
188         struct virtqueue *cvq;
189         struct net_device *dev;
190         struct send_queue *sq;
191         struct receive_queue *rq;
192         unsigned int status;
193
194         /* Max # of queue pairs supported by the device */
195         u16 max_queue_pairs;
196
197         /* # of queue pairs currently used by the driver */
198         u16 curr_queue_pairs;
199
200         /* # of XDP queue pairs currently used by the driver */
201         u16 xdp_queue_pairs;
202
203         /* I like... big packets and I cannot lie! */
204         bool big_packets;
205
206         /* Host will merge rx buffers for big packets (shake it! shake it!) */
207         bool mergeable_rx_bufs;
208
209         /* Has control virtqueue */
210         bool has_cvq;
211
212         /* Host can handle any s/g split between our header and packet data */
213         bool any_header_sg;
214
215         /* Packet virtio header size */
216         u8 hdr_len;
217
218         /* Work struct for refilling if we run low on memory. */
219         struct delayed_work refill;
220
221         /* Work struct for config space updates */
222         struct work_struct config_work;
223
224         /* Does the affinity hint is set for virtqueues? */
225         bool affinity_hint_set;
226
227         /* CPU hotplug instances for online & dead */
228         struct hlist_node node;
229         struct hlist_node node_dead;
230
231         struct control_buf *ctrl;
232
233         /* Ethtool settings */
234         u8 duplex;
235         u32 speed;
236
237         unsigned long guest_offloads;
238
239         /* failover when STANDBY feature enabled */
240         struct failover *failover;
241 };
242
243 struct padded_vnet_hdr {
244         struct virtio_net_hdr_mrg_rxbuf hdr;
245         /*
246          * hdr is in a separate sg buffer, and data sg buffer shares same page
247          * with this header sg. This padding makes next sg 16 byte aligned
248          * after the header.
249          */
250         char padding[4];
251 };
252
253 /* Converting between virtqueue no. and kernel tx/rx queue no.
254  * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
255  */
256 static int vq2txq(struct virtqueue *vq)
257 {
258         return (vq->index - 1) / 2;
259 }
260
261 static int txq2vq(int txq)
262 {
263         return txq * 2 + 1;
264 }
265
266 static int vq2rxq(struct virtqueue *vq)
267 {
268         return vq->index / 2;
269 }
270
271 static int rxq2vq(int rxq)
272 {
273         return rxq * 2;
274 }
275
276 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
277 {
278         return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
279 }
280
281 /*
282  * private is used to chain pages for big packets, put the whole
283  * most recent used list in the beginning for reuse
284  */
285 static void give_pages(struct receive_queue *rq, struct page *page)
286 {
287         struct page *end;
288
289         /* Find end of list, sew whole thing into vi->rq.pages. */
290         for (end = page; end->private; end = (struct page *)end->private);
291         end->private = (unsigned long)rq->pages;
292         rq->pages = page;
293 }
294
295 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
296 {
297         struct page *p = rq->pages;
298
299         if (p) {
300                 rq->pages = (struct page *)p->private;
301                 /* clear private here, it is used to chain pages */
302                 p->private = 0;
303         } else
304                 p = alloc_page(gfp_mask);
305         return p;
306 }
307
308 static void virtqueue_napi_schedule(struct napi_struct *napi,
309                                     struct virtqueue *vq)
310 {
311         if (napi_schedule_prep(napi)) {
312                 virtqueue_disable_cb(vq);
313                 __napi_schedule(napi);
314         }
315 }
316
317 static void virtqueue_napi_complete(struct napi_struct *napi,
318                                     struct virtqueue *vq, int processed)
319 {
320         int opaque;
321
322         opaque = virtqueue_enable_cb_prepare(vq);
323         if (napi_complete_done(napi, processed)) {
324                 if (unlikely(virtqueue_poll(vq, opaque)))
325                         virtqueue_napi_schedule(napi, vq);
326         } else {
327                 virtqueue_disable_cb(vq);
328         }
329 }
330
331 static void skb_xmit_done(struct virtqueue *vq)
332 {
333         struct virtnet_info *vi = vq->vdev->priv;
334         struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
335
336         /* Suppress further interrupts. */
337         virtqueue_disable_cb(vq);
338
339         if (napi->weight)
340                 virtqueue_napi_schedule(napi, vq);
341         else
342                 /* We were probably waiting for more output buffers. */
343                 netif_wake_subqueue(vi->dev, vq2txq(vq));
344 }
345
346 #define MRG_CTX_HEADER_SHIFT 22
347 static void *mergeable_len_to_ctx(unsigned int truesize,
348                                   unsigned int headroom)
349 {
350         return (void *)(unsigned long)((headroom << MRG_CTX_HEADER_SHIFT) | truesize);
351 }
352
353 static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx)
354 {
355         return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT;
356 }
357
358 static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx)
359 {
360         return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1);
361 }
362
363 /* Called from bottom half context */
364 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
365                                    struct receive_queue *rq,
366                                    struct page *page, unsigned int offset,
367                                    unsigned int len, unsigned int truesize)
368 {
369         struct sk_buff *skb;
370         struct virtio_net_hdr_mrg_rxbuf *hdr;
371         unsigned int copy, hdr_len, hdr_padded_len;
372         char *p;
373
374         p = page_address(page) + offset;
375
376         /* copy small packet so we can reuse these pages for small data */
377         skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
378         if (unlikely(!skb))
379                 return NULL;
380
381         hdr = skb_vnet_hdr(skb);
382
383         hdr_len = vi->hdr_len;
384         if (vi->mergeable_rx_bufs)
385                 hdr_padded_len = sizeof(*hdr);
386         else
387                 hdr_padded_len = sizeof(struct padded_vnet_hdr);
388
389         memcpy(hdr, p, hdr_len);
390
391         len -= hdr_len;
392         offset += hdr_padded_len;
393         p += hdr_padded_len;
394
395         copy = len;
396         if (copy > skb_tailroom(skb))
397                 copy = skb_tailroom(skb);
398         skb_put_data(skb, p, copy);
399
400         len -= copy;
401         offset += copy;
402
403         if (vi->mergeable_rx_bufs) {
404                 if (len)
405                         skb_add_rx_frag(skb, 0, page, offset, len, truesize);
406                 else
407                         put_page(page);
408                 return skb;
409         }
410
411         /*
412          * Verify that we can indeed put this data into a skb.
413          * This is here to handle cases when the device erroneously
414          * tries to receive more than is possible. This is usually
415          * the case of a broken device.
416          */
417         if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
418                 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
419                 dev_kfree_skb(skb);
420                 return NULL;
421         }
422         BUG_ON(offset >= PAGE_SIZE);
423         while (len) {
424                 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
425                 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
426                                 frag_size, truesize);
427                 len -= frag_size;
428                 page = (struct page *)page->private;
429                 offset = 0;
430         }
431
432         if (page)
433                 give_pages(rq, page);
434
435         return skb;
436 }
437
438 static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
439                                    struct send_queue *sq,
440                                    struct xdp_frame *xdpf)
441 {
442         struct virtio_net_hdr_mrg_rxbuf *hdr;
443         int err;
444
445         /* virtqueue want to use data area in-front of packet */
446         if (unlikely(xdpf->metasize > 0))
447                 return -EOPNOTSUPP;
448
449         if (unlikely(xdpf->headroom < vi->hdr_len))
450                 return -EOVERFLOW;
451
452         /* Make room for virtqueue hdr (also change xdpf->headroom?) */
453         xdpf->data -= vi->hdr_len;
454         /* Zero header and leave csum up to XDP layers */
455         hdr = xdpf->data;
456         memset(hdr, 0, vi->hdr_len);
457         xdpf->len   += vi->hdr_len;
458
459         sg_init_one(sq->sg, xdpf->data, xdpf->len);
460
461         err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdpf, GFP_ATOMIC);
462         if (unlikely(err))
463                 return -ENOSPC; /* Caller handle free/refcnt */
464
465         return 0;
466 }
467
468 static struct send_queue *virtnet_xdp_sq(struct virtnet_info *vi)
469 {
470         unsigned int qp;
471
472         qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
473         return &vi->sq[qp];
474 }
475
476 static int virtnet_xdp_xmit(struct net_device *dev,
477                             int n, struct xdp_frame **frames, u32 flags)
478 {
479         struct virtnet_info *vi = netdev_priv(dev);
480         struct receive_queue *rq = vi->rq;
481         struct xdp_frame *xdpf_sent;
482         struct bpf_prog *xdp_prog;
483         struct send_queue *sq;
484         unsigned int len;
485         int drops = 0;
486         int kicks = 0;
487         int ret, err;
488         int i;
489
490         sq = virtnet_xdp_sq(vi);
491
492         if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) {
493                 ret = -EINVAL;
494                 drops = n;
495                 goto out;
496         }
497
498         /* Only allow ndo_xdp_xmit if XDP is loaded on dev, as this
499          * indicate XDP resources have been successfully allocated.
500          */
501         xdp_prog = rcu_dereference(rq->xdp_prog);
502         if (!xdp_prog) {
503                 ret = -ENXIO;
504                 drops = n;
505                 goto out;
506         }
507
508         /* Free up any pending old buffers before queueing new ones. */
509         while ((xdpf_sent = virtqueue_get_buf(sq->vq, &len)) != NULL)
510                 xdp_return_frame(xdpf_sent);
511
512         for (i = 0; i < n; i++) {
513                 struct xdp_frame *xdpf = frames[i];
514
515                 err = __virtnet_xdp_xmit_one(vi, sq, xdpf);
516                 if (err) {
517                         xdp_return_frame_rx_napi(xdpf);
518                         drops++;
519                 }
520         }
521         ret = n - drops;
522
523         if (flags & XDP_XMIT_FLUSH) {
524                 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
525                         kicks = 1;
526         }
527 out:
528         u64_stats_update_begin(&sq->stats.syncp);
529         sq->stats.xdp_tx += n;
530         sq->stats.xdp_tx_drops += drops;
531         sq->stats.kicks += kicks;
532         u64_stats_update_end(&sq->stats.syncp);
533
534         return ret;
535 }
536
537 static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
538 {
539         return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0;
540 }
541
542 /* We copy the packet for XDP in the following cases:
543  *
544  * 1) Packet is scattered across multiple rx buffers.
545  * 2) Headroom space is insufficient.
546  *
547  * This is inefficient but it's a temporary condition that
548  * we hit right after XDP is enabled and until queue is refilled
549  * with large buffers with sufficient headroom - so it should affect
550  * at most queue size packets.
551  * Afterwards, the conditions to enable
552  * XDP should preclude the underlying device from sending packets
553  * across multiple buffers (num_buf > 1), and we make sure buffers
554  * have enough headroom.
555  */
556 static struct page *xdp_linearize_page(struct receive_queue *rq,
557                                        u16 *num_buf,
558                                        struct page *p,
559                                        int offset,
560                                        int page_off,
561                                        unsigned int *len)
562 {
563         struct page *page = alloc_page(GFP_ATOMIC);
564
565         if (!page)
566                 return NULL;
567
568         memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
569         page_off += *len;
570
571         while (--*num_buf) {
572                 int tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
573                 unsigned int buflen;
574                 void *buf;
575                 int off;
576
577                 buf = virtqueue_get_buf(rq->vq, &buflen);
578                 if (unlikely(!buf))
579                         goto err_buf;
580
581                 p = virt_to_head_page(buf);
582                 off = buf - page_address(p);
583
584                 /* guard against a misconfigured or uncooperative backend that
585                  * is sending packet larger than the MTU.
586                  */
587                 if ((page_off + buflen + tailroom) > PAGE_SIZE) {
588                         put_page(p);
589                         goto err_buf;
590                 }
591
592                 memcpy(page_address(page) + page_off,
593                        page_address(p) + off, buflen);
594                 page_off += buflen;
595                 put_page(p);
596         }
597
598         /* Headroom does not contribute to packet length */
599         *len = page_off - VIRTIO_XDP_HEADROOM;
600         return page;
601 err_buf:
602         __free_pages(page, 0);
603         return NULL;
604 }
605
606 static struct sk_buff *receive_small(struct net_device *dev,
607                                      struct virtnet_info *vi,
608                                      struct receive_queue *rq,
609                                      void *buf, void *ctx,
610                                      unsigned int len,
611                                      unsigned int *xdp_xmit,
612                                      struct virtnet_rq_stats *stats)
613 {
614         struct sk_buff *skb;
615         struct bpf_prog *xdp_prog;
616         unsigned int xdp_headroom = (unsigned long)ctx;
617         unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
618         unsigned int headroom = vi->hdr_len + header_offset;
619         unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
620                               SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
621         struct page *page = virt_to_head_page(buf);
622         unsigned int delta = 0;
623         struct page *xdp_page;
624         int err;
625
626         len -= vi->hdr_len;
627         stats->bytes += len;
628
629         rcu_read_lock();
630         xdp_prog = rcu_dereference(rq->xdp_prog);
631         if (xdp_prog) {
632                 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
633                 struct xdp_frame *xdpf;
634                 struct xdp_buff xdp;
635                 void *orig_data;
636                 u32 act;
637
638                 if (unlikely(hdr->hdr.gso_type))
639                         goto err_xdp;
640
641                 if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
642                         int offset = buf - page_address(page) + header_offset;
643                         unsigned int tlen = len + vi->hdr_len;
644                         u16 num_buf = 1;
645
646                         xdp_headroom = virtnet_get_headroom(vi);
647                         header_offset = VIRTNET_RX_PAD + xdp_headroom;
648                         headroom = vi->hdr_len + header_offset;
649                         buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
650                                  SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
651                         xdp_page = xdp_linearize_page(rq, &num_buf, page,
652                                                       offset, header_offset,
653                                                       &tlen);
654                         if (!xdp_page)
655                                 goto err_xdp;
656
657                         buf = page_address(xdp_page);
658                         put_page(page);
659                         page = xdp_page;
660                 }
661
662                 xdp.data_hard_start = buf + VIRTNET_RX_PAD + vi->hdr_len;
663                 xdp.data = xdp.data_hard_start + xdp_headroom;
664                 xdp_set_data_meta_invalid(&xdp);
665                 xdp.data_end = xdp.data + len;
666                 xdp.rxq = &rq->xdp_rxq;
667                 orig_data = xdp.data;
668                 act = bpf_prog_run_xdp(xdp_prog, &xdp);
669                 stats->xdp_packets++;
670
671                 switch (act) {
672                 case XDP_PASS:
673                         /* Recalculate length in case bpf program changed it */
674                         delta = orig_data - xdp.data;
675                         len = xdp.data_end - xdp.data;
676                         break;
677                 case XDP_TX:
678                         stats->xdp_tx++;
679                         xdpf = convert_to_xdp_frame(&xdp);
680                         if (unlikely(!xdpf))
681                                 goto err_xdp;
682                         err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
683                         if (unlikely(err < 0)) {
684                                 trace_xdp_exception(vi->dev, xdp_prog, act);
685                                 goto err_xdp;
686                         }
687                         *xdp_xmit |= VIRTIO_XDP_TX;
688                         rcu_read_unlock();
689                         goto xdp_xmit;
690                 case XDP_REDIRECT:
691                         stats->xdp_redirects++;
692                         err = xdp_do_redirect(dev, &xdp, xdp_prog);
693                         if (err)
694                                 goto err_xdp;
695                         *xdp_xmit |= VIRTIO_XDP_REDIR;
696                         rcu_read_unlock();
697                         goto xdp_xmit;
698                 default:
699                         bpf_warn_invalid_xdp_action(act);
700                         /* fall through */
701                 case XDP_ABORTED:
702                         trace_xdp_exception(vi->dev, xdp_prog, act);
703                 case XDP_DROP:
704                         goto err_xdp;
705                 }
706         }
707         rcu_read_unlock();
708
709         skb = build_skb(buf, buflen);
710         if (!skb) {
711                 put_page(page);
712                 goto err;
713         }
714         skb_reserve(skb, headroom - delta);
715         skb_put(skb, len);
716         if (!delta) {
717                 buf += header_offset;
718                 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
719         } /* keep zeroed vnet hdr since packet was changed by bpf */
720
721 err:
722         return skb;
723
724 err_xdp:
725         rcu_read_unlock();
726         stats->xdp_drops++;
727         stats->drops++;
728         put_page(page);
729 xdp_xmit:
730         return NULL;
731 }
732
733 static struct sk_buff *receive_big(struct net_device *dev,
734                                    struct virtnet_info *vi,
735                                    struct receive_queue *rq,
736                                    void *buf,
737                                    unsigned int len,
738                                    struct virtnet_rq_stats *stats)
739 {
740         struct page *page = buf;
741         struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);
742
743         stats->bytes += len - vi->hdr_len;
744         if (unlikely(!skb))
745                 goto err;
746
747         return skb;
748
749 err:
750         stats->drops++;
751         give_pages(rq, page);
752         return NULL;
753 }
754
755 static struct sk_buff *receive_mergeable(struct net_device *dev,
756                                          struct virtnet_info *vi,
757                                          struct receive_queue *rq,
758                                          void *buf,
759                                          void *ctx,
760                                          unsigned int len,
761                                          unsigned int *xdp_xmit,
762                                          struct virtnet_rq_stats *stats)
763 {
764         struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
765         u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
766         struct page *page = virt_to_head_page(buf);
767         int offset = buf - page_address(page);
768         struct sk_buff *head_skb, *curr_skb;
769         struct bpf_prog *xdp_prog;
770         unsigned int truesize;
771         unsigned int headroom = mergeable_ctx_to_headroom(ctx);
772         int err;
773
774         head_skb = NULL;
775         stats->bytes += len - vi->hdr_len;
776
777         rcu_read_lock();
778         xdp_prog = rcu_dereference(rq->xdp_prog);
779         if (xdp_prog) {
780                 struct xdp_frame *xdpf;
781                 struct page *xdp_page;
782                 struct xdp_buff xdp;
783                 void *data;
784                 u32 act;
785
786                 /* Transient failure which in theory could occur if
787                  * in-flight packets from before XDP was enabled reach
788                  * the receive path after XDP is loaded.
789                  */
790                 if (unlikely(hdr->hdr.gso_type))
791                         goto err_xdp;
792
793                 /* This happens when rx buffer size is underestimated
794                  * or headroom is not enough because of the buffer
795                  * was refilled before XDP is set. This should only
796                  * happen for the first several packets, so we don't
797                  * care much about its performance.
798                  */
799                 if (unlikely(num_buf > 1 ||
800                              headroom < virtnet_get_headroom(vi))) {
801                         /* linearize data for XDP */
802                         xdp_page = xdp_linearize_page(rq, &num_buf,
803                                                       page, offset,
804                                                       VIRTIO_XDP_HEADROOM,
805                                                       &len);
806                         if (!xdp_page)
807                                 goto err_xdp;
808                         offset = VIRTIO_XDP_HEADROOM;
809                 } else {
810                         xdp_page = page;
811                 }
812
813                 /* Allow consuming headroom but reserve enough space to push
814                  * the descriptor on if we get an XDP_TX return code.
815                  */
816                 data = page_address(xdp_page) + offset;
817                 xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len;
818                 xdp.data = data + vi->hdr_len;
819                 xdp_set_data_meta_invalid(&xdp);
820                 xdp.data_end = xdp.data + (len - vi->hdr_len);
821                 xdp.rxq = &rq->xdp_rxq;
822
823                 act = bpf_prog_run_xdp(xdp_prog, &xdp);
824                 stats->xdp_packets++;
825
826                 switch (act) {
827                 case XDP_PASS:
828                         /* recalculate offset to account for any header
829                          * adjustments. Note other cases do not build an
830                          * skb and avoid using offset
831                          */
832                         offset = xdp.data -
833                                         page_address(xdp_page) - vi->hdr_len;
834
835                         /* recalculate len if xdp.data or xdp.data_end were
836                          * adjusted
837                          */
838                         len = xdp.data_end - xdp.data + vi->hdr_len;
839                         /* We can only create skb based on xdp_page. */
840                         if (unlikely(xdp_page != page)) {
841                                 rcu_read_unlock();
842                                 put_page(page);
843                                 head_skb = page_to_skb(vi, rq, xdp_page,
844                                                        offset, len, PAGE_SIZE);
845                                 return head_skb;
846                         }
847                         break;
848                 case XDP_TX:
849                         stats->xdp_tx++;
850                         xdpf = convert_to_xdp_frame(&xdp);
851                         if (unlikely(!xdpf))
852                                 goto err_xdp;
853                         err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
854                         if (unlikely(err < 0)) {
855                                 trace_xdp_exception(vi->dev, xdp_prog, act);
856                                 if (unlikely(xdp_page != page))
857                                         put_page(xdp_page);
858                                 goto err_xdp;
859                         }
860                         *xdp_xmit |= VIRTIO_XDP_TX;
861                         if (unlikely(xdp_page != page))
862                                 put_page(page);
863                         rcu_read_unlock();
864                         goto xdp_xmit;
865                 case XDP_REDIRECT:
866                         stats->xdp_redirects++;
867                         err = xdp_do_redirect(dev, &xdp, xdp_prog);
868                         if (err) {
869                                 if (unlikely(xdp_page != page))
870                                         put_page(xdp_page);
871                                 goto err_xdp;
872                         }
873                         *xdp_xmit |= VIRTIO_XDP_REDIR;
874                         if (unlikely(xdp_page != page))
875                                 put_page(page);
876                         rcu_read_unlock();
877                         goto xdp_xmit;
878                 default:
879                         bpf_warn_invalid_xdp_action(act);
880                         /* fall through */
881                 case XDP_ABORTED:
882                         trace_xdp_exception(vi->dev, xdp_prog, act);
883                         /* fall through */
884                 case XDP_DROP:
885                         if (unlikely(xdp_page != page))
886                                 __free_pages(xdp_page, 0);
887                         goto err_xdp;
888                 }
889         }
890         rcu_read_unlock();
891
892         truesize = mergeable_ctx_to_truesize(ctx);
893         if (unlikely(len > truesize)) {
894                 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
895                          dev->name, len, (unsigned long)ctx);
896                 dev->stats.rx_length_errors++;
897                 goto err_skb;
898         }
899
900         head_skb = page_to_skb(vi, rq, page, offset, len, truesize);
901         curr_skb = head_skb;
902
903         if (unlikely(!curr_skb))
904                 goto err_skb;
905         while (--num_buf) {
906                 int num_skb_frags;
907
908                 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
909                 if (unlikely(!buf)) {
910                         pr_debug("%s: rx error: %d buffers out of %d missing\n",
911                                  dev->name, num_buf,
912                                  virtio16_to_cpu(vi->vdev,
913                                                  hdr->num_buffers));
914                         dev->stats.rx_length_errors++;
915                         goto err_buf;
916                 }
917
918                 stats->bytes += len;
919                 page = virt_to_head_page(buf);
920
921                 truesize = mergeable_ctx_to_truesize(ctx);
922                 if (unlikely(len > truesize)) {
923                         pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
924                                  dev->name, len, (unsigned long)ctx);
925                         dev->stats.rx_length_errors++;
926                         goto err_skb;
927                 }
928
929                 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
930                 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
931                         struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
932
933                         if (unlikely(!nskb))
934                                 goto err_skb;
935                         if (curr_skb == head_skb)
936                                 skb_shinfo(curr_skb)->frag_list = nskb;
937                         else
938                                 curr_skb->next = nskb;
939                         curr_skb = nskb;
940                         head_skb->truesize += nskb->truesize;
941                         num_skb_frags = 0;
942                 }
943                 if (curr_skb != head_skb) {
944                         head_skb->data_len += len;
945                         head_skb->len += len;
946                         head_skb->truesize += truesize;
947                 }
948                 offset = buf - page_address(page);
949                 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
950                         put_page(page);
951                         skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
952                                              len, truesize);
953                 } else {
954                         skb_add_rx_frag(curr_skb, num_skb_frags, page,
955                                         offset, len, truesize);
956                 }
957         }
958
959         ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
960         return head_skb;
961
962 err_xdp:
963         rcu_read_unlock();
964         stats->xdp_drops++;
965 err_skb:
966         put_page(page);
967         while (num_buf-- > 1) {
968                 buf = virtqueue_get_buf(rq->vq, &len);
969                 if (unlikely(!buf)) {
970                         pr_debug("%s: rx error: %d buffers missing\n",
971                                  dev->name, num_buf);
972                         dev->stats.rx_length_errors++;
973                         break;
974                 }
975                 stats->bytes += len;
976                 page = virt_to_head_page(buf);
977                 put_page(page);
978         }
979 err_buf:
980         stats->drops++;
981         dev_kfree_skb(head_skb);
982 xdp_xmit:
983         return NULL;
984 }
985
986 static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
987                         void *buf, unsigned int len, void **ctx,
988                         unsigned int *xdp_xmit,
989                         struct virtnet_rq_stats *stats)
990 {
991         struct net_device *dev = vi->dev;
992         struct sk_buff *skb;
993         struct virtio_net_hdr_mrg_rxbuf *hdr;
994
995         if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
996                 pr_debug("%s: short packet %i\n", dev->name, len);
997                 dev->stats.rx_length_errors++;
998                 if (vi->mergeable_rx_bufs) {
999                         put_page(virt_to_head_page(buf));
1000                 } else if (vi->big_packets) {
1001                         give_pages(rq, buf);
1002                 } else {
1003                         put_page(virt_to_head_page(buf));
1004                 }
1005                 return;
1006         }
1007
1008         if (vi->mergeable_rx_bufs)
1009                 skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit,
1010                                         stats);
1011         else if (vi->big_packets)
1012                 skb = receive_big(dev, vi, rq, buf, len, stats);
1013         else
1014                 skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats);
1015
1016         if (unlikely(!skb))
1017                 return;
1018
1019         hdr = skb_vnet_hdr(skb);
1020
1021         if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
1022                 skb->ip_summed = CHECKSUM_UNNECESSARY;
1023
1024         if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
1025                                   virtio_is_little_endian(vi->vdev))) {
1026                 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
1027                                      dev->name, hdr->hdr.gso_type,
1028                                      hdr->hdr.gso_size);
1029                 goto frame_err;
1030         }
1031
1032         skb->protocol = eth_type_trans(skb, dev);
1033         pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
1034                  ntohs(skb->protocol), skb->len, skb->pkt_type);
1035
1036         napi_gro_receive(&rq->napi, skb);
1037         return;
1038
1039 frame_err:
1040         dev->stats.rx_frame_errors++;
1041         dev_kfree_skb(skb);
1042 }
1043
1044 /* Unlike mergeable buffers, all buffers are allocated to the
1045  * same size, except for the headroom. For this reason we do
1046  * not need to use  mergeable_len_to_ctx here - it is enough
1047  * to store the headroom as the context ignoring the truesize.
1048  */
1049 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
1050                              gfp_t gfp)
1051 {
1052         struct page_frag *alloc_frag = &rq->alloc_frag;
1053         char *buf;
1054         unsigned int xdp_headroom = virtnet_get_headroom(vi);
1055         void *ctx = (void *)(unsigned long)xdp_headroom;
1056         int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
1057         int err;
1058
1059         len = SKB_DATA_ALIGN(len) +
1060               SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
1061         if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
1062                 return -ENOMEM;
1063
1064         buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1065         get_page(alloc_frag->page);
1066         alloc_frag->offset += len;
1067         sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
1068                     vi->hdr_len + GOOD_PACKET_LEN);
1069         err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1070         if (err < 0)
1071                 put_page(virt_to_head_page(buf));
1072         return err;
1073 }
1074
1075 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
1076                            gfp_t gfp)
1077 {
1078         struct page *first, *list = NULL;
1079         char *p;
1080         int i, err, offset;
1081
1082         sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
1083
1084         /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
1085         for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
1086                 first = get_a_page(rq, gfp);
1087                 if (!first) {
1088                         if (list)
1089                                 give_pages(rq, list);
1090                         return -ENOMEM;
1091                 }
1092                 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
1093
1094                 /* chain new page in list head to match sg */
1095                 first->private = (unsigned long)list;
1096                 list = first;
1097         }
1098
1099         first = get_a_page(rq, gfp);
1100         if (!first) {
1101                 give_pages(rq, list);
1102                 return -ENOMEM;
1103         }
1104         p = page_address(first);
1105
1106         /* rq->sg[0], rq->sg[1] share the same page */
1107         /* a separated rq->sg[0] for header - required in case !any_header_sg */
1108         sg_set_buf(&rq->sg[0], p, vi->hdr_len);
1109
1110         /* rq->sg[1] for data packet, from offset */
1111         offset = sizeof(struct padded_vnet_hdr);
1112         sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
1113
1114         /* chain first in list head */
1115         first->private = (unsigned long)list;
1116         err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
1117                                   first, gfp);
1118         if (err < 0)
1119                 give_pages(rq, first);
1120
1121         return err;
1122 }
1123
1124 static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
1125                                           struct ewma_pkt_len *avg_pkt_len,
1126                                           unsigned int room)
1127 {
1128         const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
1129         unsigned int len;
1130
1131         if (room)
1132                 return PAGE_SIZE - room;
1133
1134         len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
1135                                 rq->min_buf_len, PAGE_SIZE - hdr_len);
1136
1137         return ALIGN(len, L1_CACHE_BYTES);
1138 }
1139
1140 static int add_recvbuf_mergeable(struct virtnet_info *vi,
1141                                  struct receive_queue *rq, gfp_t gfp)
1142 {
1143         struct page_frag *alloc_frag = &rq->alloc_frag;
1144         unsigned int headroom = virtnet_get_headroom(vi);
1145         unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
1146         unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
1147         char *buf;
1148         void *ctx;
1149         int err;
1150         unsigned int len, hole;
1151
1152         /* Extra tailroom is needed to satisfy XDP's assumption. This
1153          * means rx frags coalescing won't work, but consider we've
1154          * disabled GSO for XDP, it won't be a big issue.
1155          */
1156         len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len, room);
1157         if (unlikely(!skb_page_frag_refill(len + room, alloc_frag, gfp)))
1158                 return -ENOMEM;
1159
1160         buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1161         buf += headroom; /* advance address leaving hole at front of pkt */
1162         get_page(alloc_frag->page);
1163         alloc_frag->offset += len + room;
1164         hole = alloc_frag->size - alloc_frag->offset;
1165         if (hole < len + room) {
1166                 /* To avoid internal fragmentation, if there is very likely not
1167                  * enough space for another buffer, add the remaining space to
1168                  * the current buffer.
1169                  */
1170                 len += hole;
1171                 alloc_frag->offset += hole;
1172         }
1173
1174         sg_init_one(rq->sg, buf, len);
1175         ctx = mergeable_len_to_ctx(len, headroom);
1176         err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1177         if (err < 0)
1178                 put_page(virt_to_head_page(buf));
1179
1180         return err;
1181 }
1182
1183 /*
1184  * Returns false if we couldn't fill entirely (OOM).
1185  *
1186  * Normally run in the receive path, but can also be run from ndo_open
1187  * before we're receiving packets, or from refill_work which is
1188  * careful to disable receiving (using napi_disable).
1189  */
1190 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
1191                           gfp_t gfp)
1192 {
1193         int err;
1194         bool oom;
1195
1196         do {
1197                 if (vi->mergeable_rx_bufs)
1198                         err = add_recvbuf_mergeable(vi, rq, gfp);
1199                 else if (vi->big_packets)
1200                         err = add_recvbuf_big(vi, rq, gfp);
1201                 else
1202                         err = add_recvbuf_small(vi, rq, gfp);
1203
1204                 oom = err == -ENOMEM;
1205                 if (err)
1206                         break;
1207         } while (rq->vq->num_free);
1208         if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
1209                 u64_stats_update_begin(&rq->stats.syncp);
1210                 rq->stats.kicks++;
1211                 u64_stats_update_end(&rq->stats.syncp);
1212         }
1213
1214         return !oom;
1215 }
1216
1217 static void skb_recv_done(struct virtqueue *rvq)
1218 {
1219         struct virtnet_info *vi = rvq->vdev->priv;
1220         struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
1221
1222         virtqueue_napi_schedule(&rq->napi, rvq);
1223 }
1224
1225 static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
1226 {
1227         napi_enable(napi);
1228
1229         /* If all buffers were filled by other side before we napi_enabled, we
1230          * won't get another interrupt, so process any outstanding packets now.
1231          * Call local_bh_enable after to trigger softIRQ processing.
1232          */
1233         local_bh_disable();
1234         virtqueue_napi_schedule(napi, vq);
1235         local_bh_enable();
1236 }
1237
1238 static void virtnet_napi_tx_enable(struct virtnet_info *vi,
1239                                    struct virtqueue *vq,
1240                                    struct napi_struct *napi)
1241 {
1242         if (!napi->weight)
1243                 return;
1244
1245         /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
1246          * enable the feature if this is likely affine with the transmit path.
1247          */
1248         if (!vi->affinity_hint_set) {
1249                 napi->weight = 0;
1250                 return;
1251         }
1252
1253         return virtnet_napi_enable(vq, napi);
1254 }
1255
1256 static void virtnet_napi_tx_disable(struct napi_struct *napi)
1257 {
1258         if (napi->weight)
1259                 napi_disable(napi);
1260 }
1261
1262 static void refill_work(struct work_struct *work)
1263 {
1264         struct virtnet_info *vi =
1265                 container_of(work, struct virtnet_info, refill.work);
1266         bool still_empty;
1267         int i;
1268
1269         for (i = 0; i < vi->curr_queue_pairs; i++) {
1270                 struct receive_queue *rq = &vi->rq[i];
1271
1272                 napi_disable(&rq->napi);
1273                 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
1274                 virtnet_napi_enable(rq->vq, &rq->napi);
1275
1276                 /* In theory, this can happen: if we don't get any buffers in
1277                  * we will *never* try to fill again.
1278                  */
1279                 if (still_empty)
1280                         schedule_delayed_work(&vi->refill, HZ/2);
1281         }
1282 }
1283
1284 static int virtnet_receive(struct receive_queue *rq, int budget,
1285                            unsigned int *xdp_xmit)
1286 {
1287         struct virtnet_info *vi = rq->vq->vdev->priv;
1288         struct virtnet_rq_stats stats = {};
1289         unsigned int len;
1290         void *buf;
1291         int i;
1292
1293         if (!vi->big_packets || vi->mergeable_rx_bufs) {
1294                 void *ctx;
1295
1296                 while (stats.packets < budget &&
1297                        (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) {
1298                         receive_buf(vi, rq, buf, len, ctx, xdp_xmit, &stats);
1299                         stats.packets++;
1300                 }
1301         } else {
1302                 while (stats.packets < budget &&
1303                        (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
1304                         receive_buf(vi, rq, buf, len, NULL, xdp_xmit, &stats);
1305                         stats.packets++;
1306                 }
1307         }
1308
1309         if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
1310                 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
1311                         schedule_delayed_work(&vi->refill, 0);
1312         }
1313
1314         u64_stats_update_begin(&rq->stats.syncp);
1315         for (i = 0; i < VIRTNET_RQ_STATS_LEN; i++) {
1316                 size_t offset = virtnet_rq_stats_desc[i].offset;
1317                 u64 *item;
1318
1319                 item = (u64 *)((u8 *)&rq->stats + offset);
1320                 *item += *(u64 *)((u8 *)&stats + offset);
1321         }
1322         u64_stats_update_end(&rq->stats.syncp);
1323
1324         return stats.packets;
1325 }
1326
1327 static void free_old_xmit_skbs(struct send_queue *sq)
1328 {
1329         struct sk_buff *skb;
1330         unsigned int len;
1331         unsigned int packets = 0;
1332         unsigned int bytes = 0;
1333
1334         while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1335                 pr_debug("Sent skb %p\n", skb);
1336
1337                 bytes += skb->len;
1338                 packets++;
1339
1340                 dev_consume_skb_any(skb);
1341         }
1342
1343         /* Avoid overhead when no packets have been processed
1344          * happens when called speculatively from start_xmit.
1345          */
1346         if (!packets)
1347                 return;
1348
1349         u64_stats_update_begin(&sq->stats.syncp);
1350         sq->stats.bytes += bytes;
1351         sq->stats.packets += packets;
1352         u64_stats_update_end(&sq->stats.syncp);
1353 }
1354
1355 static void virtnet_poll_cleantx(struct receive_queue *rq)
1356 {
1357         struct virtnet_info *vi = rq->vq->vdev->priv;
1358         unsigned int index = vq2rxq(rq->vq);
1359         struct send_queue *sq = &vi->sq[index];
1360         struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
1361
1362         if (!sq->napi.weight)
1363                 return;
1364
1365         if (__netif_tx_trylock(txq)) {
1366                 free_old_xmit_skbs(sq);
1367                 __netif_tx_unlock(txq);
1368         }
1369
1370         if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1371                 netif_tx_wake_queue(txq);
1372 }
1373
1374 static int virtnet_poll(struct napi_struct *napi, int budget)
1375 {
1376         struct receive_queue *rq =
1377                 container_of(napi, struct receive_queue, napi);
1378         struct virtnet_info *vi = rq->vq->vdev->priv;
1379         struct send_queue *sq;
1380         unsigned int received;
1381         unsigned int xdp_xmit = 0;
1382
1383         virtnet_poll_cleantx(rq);
1384
1385         received = virtnet_receive(rq, budget, &xdp_xmit);
1386
1387         /* Out of packets? */
1388         if (received < budget)
1389                 virtqueue_napi_complete(napi, rq->vq, received);
1390
1391         if (xdp_xmit & VIRTIO_XDP_REDIR)
1392                 xdp_do_flush_map();
1393
1394         if (xdp_xmit & VIRTIO_XDP_TX) {
1395                 sq = virtnet_xdp_sq(vi);
1396                 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1397                         u64_stats_update_begin(&sq->stats.syncp);
1398                         sq->stats.kicks++;
1399                         u64_stats_update_end(&sq->stats.syncp);
1400                 }
1401         }
1402
1403         return received;
1404 }
1405
1406 static int virtnet_open(struct net_device *dev)
1407 {
1408         struct virtnet_info *vi = netdev_priv(dev);
1409         int i, err;
1410
1411         for (i = 0; i < vi->max_queue_pairs; i++) {
1412                 if (i < vi->curr_queue_pairs)
1413                         /* Make sure we have some buffers: if oom use wq. */
1414                         if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1415                                 schedule_delayed_work(&vi->refill, 0);
1416
1417                 err = xdp_rxq_info_reg(&vi->rq[i].xdp_rxq, dev, i);
1418                 if (err < 0)
1419                         return err;
1420
1421                 err = xdp_rxq_info_reg_mem_model(&vi->rq[i].xdp_rxq,
1422                                                  MEM_TYPE_PAGE_SHARED, NULL);
1423                 if (err < 0) {
1424                         xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
1425                         return err;
1426                 }
1427
1428                 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1429                 virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
1430         }
1431
1432         return 0;
1433 }
1434
1435 static int virtnet_poll_tx(struct napi_struct *napi, int budget)
1436 {
1437         struct send_queue *sq = container_of(napi, struct send_queue, napi);
1438         struct virtnet_info *vi = sq->vq->vdev->priv;
1439         struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, vq2txq(sq->vq));
1440
1441         __netif_tx_lock(txq, raw_smp_processor_id());
1442         free_old_xmit_skbs(sq);
1443         __netif_tx_unlock(txq);
1444
1445         virtqueue_napi_complete(napi, sq->vq, 0);
1446
1447         if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1448                 netif_tx_wake_queue(txq);
1449
1450         return 0;
1451 }
1452
1453 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1454 {
1455         struct virtio_net_hdr_mrg_rxbuf *hdr;
1456         const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1457         struct virtnet_info *vi = sq->vq->vdev->priv;
1458         int num_sg;
1459         unsigned hdr_len = vi->hdr_len;
1460         bool can_push;
1461
1462         pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1463
1464         can_push = vi->any_header_sg &&
1465                 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1466                 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1467         /* Even if we can, don't push here yet as this would skew
1468          * csum_start offset below. */
1469         if (can_push)
1470                 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1471         else
1472                 hdr = skb_vnet_hdr(skb);
1473
1474         if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1475                                     virtio_is_little_endian(vi->vdev), false,
1476                                     0))
1477                 BUG();
1478
1479         if (vi->mergeable_rx_bufs)
1480                 hdr->num_buffers = 0;
1481
1482         sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1483         if (can_push) {
1484                 __skb_push(skb, hdr_len);
1485                 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1486                 if (unlikely(num_sg < 0))
1487                         return num_sg;
1488                 /* Pull header back to avoid skew in tx bytes calculations. */
1489                 __skb_pull(skb, hdr_len);
1490         } else {
1491                 sg_set_buf(sq->sg, hdr, hdr_len);
1492                 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
1493                 if (unlikely(num_sg < 0))
1494                         return num_sg;
1495                 num_sg++;
1496         }
1497         return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1498 }
1499
1500 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1501 {
1502         struct virtnet_info *vi = netdev_priv(dev);
1503         int qnum = skb_get_queue_mapping(skb);
1504         struct send_queue *sq = &vi->sq[qnum];
1505         int err;
1506         struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1507         bool kick = !skb->xmit_more;
1508         bool use_napi = sq->napi.weight;
1509
1510         /* Free up any pending old buffers before queueing new ones. */
1511         free_old_xmit_skbs(sq);
1512
1513         if (use_napi && kick)
1514                 virtqueue_enable_cb_delayed(sq->vq);
1515
1516         /* timestamp packet in software */
1517         skb_tx_timestamp(skb);
1518
1519         /* Try to transmit */
1520         err = xmit_skb(sq, skb);
1521
1522         /* This should not happen! */
1523         if (unlikely(err)) {
1524                 dev->stats.tx_fifo_errors++;
1525                 if (net_ratelimit())
1526                         dev_warn(&dev->dev,
1527                                  "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
1528                 dev->stats.tx_dropped++;
1529                 dev_kfree_skb_any(skb);
1530                 return NETDEV_TX_OK;
1531         }
1532
1533         /* Don't wait up for transmitted skbs to be freed. */
1534         if (!use_napi) {
1535                 skb_orphan(skb);
1536                 nf_reset(skb);
1537         }
1538
1539         /* If running out of space, stop queue to avoid getting packets that we
1540          * are then unable to transmit.
1541          * An alternative would be to force queuing layer to requeue the skb by
1542          * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1543          * returned in a normal path of operation: it means that driver is not
1544          * maintaining the TX queue stop/start state properly, and causes
1545          * the stack to do a non-trivial amount of useless work.
1546          * Since most packets only take 1 or 2 ring slots, stopping the queue
1547          * early means 16 slots are typically wasted.
1548          */
1549         if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1550                 netif_stop_subqueue(dev, qnum);
1551                 if (!use_napi &&
1552                     unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1553                         /* More just got used, free them then recheck. */
1554                         free_old_xmit_skbs(sq);
1555                         if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1556                                 netif_start_subqueue(dev, qnum);
1557                                 virtqueue_disable_cb(sq->vq);
1558                         }
1559                 }
1560         }
1561
1562         if (kick || netif_xmit_stopped(txq)) {
1563                 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1564                         u64_stats_update_begin(&sq->stats.syncp);
1565                         sq->stats.kicks++;
1566                         u64_stats_update_end(&sq->stats.syncp);
1567                 }
1568         }
1569
1570         return NETDEV_TX_OK;
1571 }
1572
1573 /*
1574  * Send command via the control virtqueue and check status.  Commands
1575  * supported by the hypervisor, as indicated by feature bits, should
1576  * never fail unless improperly formatted.
1577  */
1578 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1579                                  struct scatterlist *out)
1580 {
1581         struct scatterlist *sgs[4], hdr, stat;
1582         unsigned out_num = 0, tmp;
1583
1584         /* Caller should know better */
1585         BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1586
1587         vi->ctrl->status = ~0;
1588         vi->ctrl->hdr.class = class;
1589         vi->ctrl->hdr.cmd = cmd;
1590         /* Add header */
1591         sg_init_one(&hdr, &vi->ctrl->hdr, sizeof(vi->ctrl->hdr));
1592         sgs[out_num++] = &hdr;
1593
1594         if (out)
1595                 sgs[out_num++] = out;
1596
1597         /* Add return status. */
1598         sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status));
1599         sgs[out_num] = &stat;
1600
1601         BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1602         virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1603
1604         if (unlikely(!virtqueue_kick(vi->cvq)))
1605                 return vi->ctrl->status == VIRTIO_NET_OK;
1606
1607         /* Spin for a response, the kick causes an ioport write, trapping
1608          * into the hypervisor, so the request should be handled immediately.
1609          */
1610         while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1611                !virtqueue_is_broken(vi->cvq))
1612                 cpu_relax();
1613
1614         return vi->ctrl->status == VIRTIO_NET_OK;
1615 }
1616
1617 static int virtnet_set_mac_address(struct net_device *dev, void *p)
1618 {
1619         struct virtnet_info *vi = netdev_priv(dev);
1620         struct virtio_device *vdev = vi->vdev;
1621         int ret;
1622         struct sockaddr *addr;
1623         struct scatterlist sg;
1624
1625         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
1626                 return -EOPNOTSUPP;
1627
1628         addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
1629         if (!addr)
1630                 return -ENOMEM;
1631
1632         ret = eth_prepare_mac_addr_change(dev, addr);
1633         if (ret)
1634                 goto out;
1635
1636         if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1637                 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1638                 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1639                                           VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1640                         dev_warn(&vdev->dev,
1641                                  "Failed to set mac address by vq command.\n");
1642                         ret = -EINVAL;
1643                         goto out;
1644                 }
1645         } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1646                    !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1647                 unsigned int i;
1648
1649                 /* Naturally, this has an atomicity problem. */
1650                 for (i = 0; i < dev->addr_len; i++)
1651                         virtio_cwrite8(vdev,
1652                                        offsetof(struct virtio_net_config, mac) +
1653                                        i, addr->sa_data[i]);
1654         }
1655
1656         eth_commit_mac_addr_change(dev, p);
1657         ret = 0;
1658
1659 out:
1660         kfree(addr);
1661         return ret;
1662 }
1663
1664 static void virtnet_stats(struct net_device *dev,
1665                           struct rtnl_link_stats64 *tot)
1666 {
1667         struct virtnet_info *vi = netdev_priv(dev);
1668         unsigned int start;
1669         int i;
1670
1671         for (i = 0; i < vi->max_queue_pairs; i++) {
1672                 u64 tpackets, tbytes, rpackets, rbytes, rdrops;
1673                 struct receive_queue *rq = &vi->rq[i];
1674                 struct send_queue *sq = &vi->sq[i];
1675
1676                 do {
1677                         start = u64_stats_fetch_begin_irq(&sq->stats.syncp);
1678                         tpackets = sq->stats.packets;
1679                         tbytes   = sq->stats.bytes;
1680                 } while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start));
1681
1682                 do {
1683                         start = u64_stats_fetch_begin_irq(&rq->stats.syncp);
1684                         rpackets = rq->stats.packets;
1685                         rbytes   = rq->stats.bytes;
1686                         rdrops   = rq->stats.drops;
1687                 } while (u64_stats_fetch_retry_irq(&rq->stats.syncp, start));
1688
1689                 tot->rx_packets += rpackets;
1690                 tot->tx_packets += tpackets;
1691                 tot->rx_bytes   += rbytes;
1692                 tot->tx_bytes   += tbytes;
1693                 tot->rx_dropped += rdrops;
1694         }
1695
1696         tot->tx_dropped = dev->stats.tx_dropped;
1697         tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1698         tot->rx_length_errors = dev->stats.rx_length_errors;
1699         tot->rx_frame_errors = dev->stats.rx_frame_errors;
1700 }
1701
1702 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1703 {
1704         rtnl_lock();
1705         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1706                                   VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1707                 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1708         rtnl_unlock();
1709 }
1710
1711 static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1712 {
1713         struct scatterlist sg;
1714         struct net_device *dev = vi->dev;
1715
1716         if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1717                 return 0;
1718
1719         vi->ctrl->mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1720         sg_init_one(&sg, &vi->ctrl->mq, sizeof(vi->ctrl->mq));
1721
1722         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1723                                   VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1724                 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1725                          queue_pairs);
1726                 return -EINVAL;
1727         } else {
1728                 vi->curr_queue_pairs = queue_pairs;
1729                 /* virtnet_open() will refill when device is going to up. */
1730                 if (dev->flags & IFF_UP)
1731                         schedule_delayed_work(&vi->refill, 0);
1732         }
1733
1734         return 0;
1735 }
1736
1737 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1738 {
1739         int err;
1740
1741         rtnl_lock();
1742         err = _virtnet_set_queues(vi, queue_pairs);
1743         rtnl_unlock();
1744         return err;
1745 }
1746
1747 static int virtnet_close(struct net_device *dev)
1748 {
1749         struct virtnet_info *vi = netdev_priv(dev);
1750         int i;
1751
1752         /* Make sure refill_work doesn't re-enable napi! */
1753         cancel_delayed_work_sync(&vi->refill);
1754
1755         for (i = 0; i < vi->max_queue_pairs; i++) {
1756                 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
1757                 napi_disable(&vi->rq[i].napi);
1758                 virtnet_napi_tx_disable(&vi->sq[i].napi);
1759         }
1760
1761         return 0;
1762 }
1763
1764 static void virtnet_set_rx_mode(struct net_device *dev)
1765 {
1766         struct virtnet_info *vi = netdev_priv(dev);
1767         struct scatterlist sg[2];
1768         struct virtio_net_ctrl_mac *mac_data;
1769         struct netdev_hw_addr *ha;
1770         int uc_count;
1771         int mc_count;
1772         void *buf;
1773         int i;
1774
1775         /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1776         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1777                 return;
1778
1779         vi->ctrl->promisc = ((dev->flags & IFF_PROMISC) != 0);
1780         vi->ctrl->allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1781
1782         sg_init_one(sg, &vi->ctrl->promisc, sizeof(vi->ctrl->promisc));
1783
1784         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1785                                   VIRTIO_NET_CTRL_RX_PROMISC, sg))
1786                 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1787                          vi->ctrl->promisc ? "en" : "dis");
1788
1789         sg_init_one(sg, &vi->ctrl->allmulti, sizeof(vi->ctrl->allmulti));
1790
1791         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1792                                   VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1793                 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1794                          vi->ctrl->allmulti ? "en" : "dis");
1795
1796         uc_count = netdev_uc_count(dev);
1797         mc_count = netdev_mc_count(dev);
1798         /* MAC filter - use one buffer for both lists */
1799         buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1800                       (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1801         mac_data = buf;
1802         if (!buf)
1803                 return;
1804
1805         sg_init_table(sg, 2);
1806
1807         /* Store the unicast list and count in the front of the buffer */
1808         mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1809         i = 0;
1810         netdev_for_each_uc_addr(ha, dev)
1811                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1812
1813         sg_set_buf(&sg[0], mac_data,
1814                    sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1815
1816         /* multicast list and count fill the end */
1817         mac_data = (void *)&mac_data->macs[uc_count][0];
1818
1819         mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1820         i = 0;
1821         netdev_for_each_mc_addr(ha, dev)
1822                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1823
1824         sg_set_buf(&sg[1], mac_data,
1825                    sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1826
1827         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1828                                   VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1829                 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1830
1831         kfree(buf);
1832 }
1833
1834 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1835                                    __be16 proto, u16 vid)
1836 {
1837         struct virtnet_info *vi = netdev_priv(dev);
1838         struct scatterlist sg;
1839
1840         vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
1841         sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
1842
1843         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1844                                   VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1845                 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1846         return 0;
1847 }
1848
1849 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1850                                     __be16 proto, u16 vid)
1851 {
1852         struct virtnet_info *vi = netdev_priv(dev);
1853         struct scatterlist sg;
1854
1855         vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
1856         sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
1857
1858         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1859                                   VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1860                 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1861         return 0;
1862 }
1863
1864 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1865 {
1866         int i;
1867
1868         if (vi->affinity_hint_set) {
1869                 for (i = 0; i < vi->max_queue_pairs; i++) {
1870                         virtqueue_set_affinity(vi->rq[i].vq, NULL);
1871                         virtqueue_set_affinity(vi->sq[i].vq, NULL);
1872                 }
1873
1874                 vi->affinity_hint_set = false;
1875         }
1876 }
1877
1878 static void virtnet_set_affinity(struct virtnet_info *vi)
1879 {
1880         cpumask_var_t mask;
1881         int stragglers;
1882         int group_size;
1883         int i, j, cpu;
1884         int num_cpu;
1885         int stride;
1886
1887         if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) {
1888                 virtnet_clean_affinity(vi, -1);
1889                 return;
1890         }
1891
1892         num_cpu = num_online_cpus();
1893         stride = max_t(int, num_cpu / vi->curr_queue_pairs, 1);
1894         stragglers = num_cpu >= vi->curr_queue_pairs ?
1895                         num_cpu % vi->curr_queue_pairs :
1896                         0;
1897         cpu = cpumask_next(-1, cpu_online_mask);
1898
1899         for (i = 0; i < vi->curr_queue_pairs; i++) {
1900                 group_size = stride + (i < stragglers ? 1 : 0);
1901
1902                 for (j = 0; j < group_size; j++) {
1903                         cpumask_set_cpu(cpu, mask);
1904                         cpu = cpumask_next_wrap(cpu, cpu_online_mask,
1905                                                 nr_cpu_ids, false);
1906                 }
1907                 virtqueue_set_affinity(vi->rq[i].vq, mask);
1908                 virtqueue_set_affinity(vi->sq[i].vq, mask);
1909                 __netif_set_xps_queue(vi->dev, cpumask_bits(mask), i, false);
1910                 cpumask_clear(mask);
1911         }
1912
1913         vi->affinity_hint_set = true;
1914         free_cpumask_var(mask);
1915 }
1916
1917 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1918 {
1919         struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1920                                                    node);
1921         virtnet_set_affinity(vi);
1922         return 0;
1923 }
1924
1925 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1926 {
1927         struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1928                                                    node_dead);
1929         virtnet_set_affinity(vi);
1930         return 0;
1931 }
1932
1933 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
1934 {
1935         struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1936                                                    node);
1937
1938         virtnet_clean_affinity(vi, cpu);
1939         return 0;
1940 }
1941
1942 static enum cpuhp_state virtionet_online;
1943
1944 static int virtnet_cpu_notif_add(struct virtnet_info *vi)
1945 {
1946         int ret;
1947
1948         ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
1949         if (ret)
1950                 return ret;
1951         ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1952                                                &vi->node_dead);
1953         if (!ret)
1954                 return ret;
1955         cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1956         return ret;
1957 }
1958
1959 static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
1960 {
1961         cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1962         cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1963                                             &vi->node_dead);
1964 }
1965
1966 static void virtnet_get_ringparam(struct net_device *dev,
1967                                 struct ethtool_ringparam *ring)
1968 {
1969         struct virtnet_info *vi = netdev_priv(dev);
1970
1971         ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1972         ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1973         ring->rx_pending = ring->rx_max_pending;
1974         ring->tx_pending = ring->tx_max_pending;
1975 }
1976
1977
1978 static void virtnet_get_drvinfo(struct net_device *dev,
1979                                 struct ethtool_drvinfo *info)
1980 {
1981         struct virtnet_info *vi = netdev_priv(dev);
1982         struct virtio_device *vdev = vi->vdev;
1983
1984         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1985         strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1986         strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1987
1988 }
1989
1990 /* TODO: Eliminate OOO packets during switching */
1991 static int virtnet_set_channels(struct net_device *dev,
1992                                 struct ethtool_channels *channels)
1993 {
1994         struct virtnet_info *vi = netdev_priv(dev);
1995         u16 queue_pairs = channels->combined_count;
1996         int err;
1997
1998         /* We don't support separate rx/tx channels.
1999          * We don't allow setting 'other' channels.
2000          */
2001         if (channels->rx_count || channels->tx_count || channels->other_count)
2002                 return -EINVAL;
2003
2004         if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
2005                 return -EINVAL;
2006
2007         /* For now we don't support modifying channels while XDP is loaded
2008          * also when XDP is loaded all RX queues have XDP programs so we only
2009          * need to check a single RX queue.
2010          */
2011         if (vi->rq[0].xdp_prog)
2012                 return -EINVAL;
2013
2014         get_online_cpus();
2015         err = _virtnet_set_queues(vi, queue_pairs);
2016         if (!err) {
2017                 netif_set_real_num_tx_queues(dev, queue_pairs);
2018                 netif_set_real_num_rx_queues(dev, queue_pairs);
2019
2020                 virtnet_set_affinity(vi);
2021         }
2022         put_online_cpus();
2023
2024         return err;
2025 }
2026
2027 static void virtnet_get_strings(struct net_device *dev, u32 stringset, u8 *data)
2028 {
2029         struct virtnet_info *vi = netdev_priv(dev);
2030         char *p = (char *)data;
2031         unsigned int i, j;
2032
2033         switch (stringset) {
2034         case ETH_SS_STATS:
2035                 for (i = 0; i < vi->curr_queue_pairs; i++) {
2036                         for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
2037                                 snprintf(p, ETH_GSTRING_LEN, "rx_queue_%u_%s",
2038                                          i, virtnet_rq_stats_desc[j].desc);
2039                                 p += ETH_GSTRING_LEN;
2040                         }
2041                 }
2042
2043                 for (i = 0; i < vi->curr_queue_pairs; i++) {
2044                         for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
2045                                 snprintf(p, ETH_GSTRING_LEN, "tx_queue_%u_%s",
2046                                          i, virtnet_sq_stats_desc[j].desc);
2047                                 p += ETH_GSTRING_LEN;
2048                         }
2049                 }
2050                 break;
2051         }
2052 }
2053
2054 static int virtnet_get_sset_count(struct net_device *dev, int sset)
2055 {
2056         struct virtnet_info *vi = netdev_priv(dev);
2057
2058         switch (sset) {
2059         case ETH_SS_STATS:
2060                 return vi->curr_queue_pairs * (VIRTNET_RQ_STATS_LEN +
2061                                                VIRTNET_SQ_STATS_LEN);
2062         default:
2063                 return -EOPNOTSUPP;
2064         }
2065 }
2066
2067 static void virtnet_get_ethtool_stats(struct net_device *dev,
2068                                       struct ethtool_stats *stats, u64 *data)
2069 {
2070         struct virtnet_info *vi = netdev_priv(dev);
2071         unsigned int idx = 0, start, i, j;
2072         const u8 *stats_base;
2073         size_t offset;
2074
2075         for (i = 0; i < vi->curr_queue_pairs; i++) {
2076                 struct receive_queue *rq = &vi->rq[i];
2077
2078                 stats_base = (u8 *)&rq->stats;
2079                 do {
2080                         start = u64_stats_fetch_begin_irq(&rq->stats.syncp);
2081                         for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
2082                                 offset = virtnet_rq_stats_desc[j].offset;
2083                                 data[idx + j] = *(u64 *)(stats_base + offset);
2084                         }
2085                 } while (u64_stats_fetch_retry_irq(&rq->stats.syncp, start));
2086                 idx += VIRTNET_RQ_STATS_LEN;
2087         }
2088
2089         for (i = 0; i < vi->curr_queue_pairs; i++) {
2090                 struct send_queue *sq = &vi->sq[i];
2091
2092                 stats_base = (u8 *)&sq->stats;
2093                 do {
2094                         start = u64_stats_fetch_begin_irq(&sq->stats.syncp);
2095                         for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
2096                                 offset = virtnet_sq_stats_desc[j].offset;
2097                                 data[idx + j] = *(u64 *)(stats_base + offset);
2098                         }
2099                 } while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start));
2100                 idx += VIRTNET_SQ_STATS_LEN;
2101         }
2102 }
2103
2104 static void virtnet_get_channels(struct net_device *dev,
2105                                  struct ethtool_channels *channels)
2106 {
2107         struct virtnet_info *vi = netdev_priv(dev);
2108
2109         channels->combined_count = vi->curr_queue_pairs;
2110         channels->max_combined = vi->max_queue_pairs;
2111         channels->max_other = 0;
2112         channels->rx_count = 0;
2113         channels->tx_count = 0;
2114         channels->other_count = 0;
2115 }
2116
2117 /* Check if the user is trying to change anything besides speed/duplex */
2118 static bool
2119 virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings *cmd)
2120 {
2121         struct ethtool_link_ksettings diff1 = *cmd;
2122         struct ethtool_link_ksettings diff2 = {};
2123
2124         /* cmd is always set so we need to clear it, validate the port type
2125          * and also without autonegotiation we can ignore advertising
2126          */
2127         diff1.base.speed = 0;
2128         diff2.base.port = PORT_OTHER;
2129         ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
2130         diff1.base.duplex = 0;
2131         diff1.base.cmd = 0;
2132         diff1.base.link_mode_masks_nwords = 0;
2133
2134         return !memcmp(&diff1.base, &diff2.base, sizeof(diff1.base)) &&
2135                 bitmap_empty(diff1.link_modes.supported,
2136                              __ETHTOOL_LINK_MODE_MASK_NBITS) &&
2137                 bitmap_empty(diff1.link_modes.advertising,
2138                              __ETHTOOL_LINK_MODE_MASK_NBITS) &&
2139                 bitmap_empty(diff1.link_modes.lp_advertising,
2140                              __ETHTOOL_LINK_MODE_MASK_NBITS);
2141 }
2142
2143 static int virtnet_set_link_ksettings(struct net_device *dev,
2144                                       const struct ethtool_link_ksettings *cmd)
2145 {
2146         struct virtnet_info *vi = netdev_priv(dev);
2147         u32 speed;
2148
2149         speed = cmd->base.speed;
2150         /* don't allow custom speed and duplex */
2151         if (!ethtool_validate_speed(speed) ||
2152             !ethtool_validate_duplex(cmd->base.duplex) ||
2153             !virtnet_validate_ethtool_cmd(cmd))
2154                 return -EINVAL;
2155         vi->speed = speed;
2156         vi->duplex = cmd->base.duplex;
2157
2158         return 0;
2159 }
2160
2161 static int virtnet_get_link_ksettings(struct net_device *dev,
2162                                       struct ethtool_link_ksettings *cmd)
2163 {
2164         struct virtnet_info *vi = netdev_priv(dev);
2165
2166         cmd->base.speed = vi->speed;
2167         cmd->base.duplex = vi->duplex;
2168         cmd->base.port = PORT_OTHER;
2169
2170         return 0;
2171 }
2172
2173 static int virtnet_set_coalesce(struct net_device *dev,
2174                                 struct ethtool_coalesce *ec)
2175 {
2176         struct ethtool_coalesce ec_default = {
2177                 .cmd = ETHTOOL_SCOALESCE,
2178                 .rx_max_coalesced_frames = 1,
2179         };
2180         struct virtnet_info *vi = netdev_priv(dev);
2181         int i, napi_weight;
2182
2183         if (ec->tx_max_coalesced_frames > 1)
2184                 return -EINVAL;
2185
2186         ec_default.tx_max_coalesced_frames = ec->tx_max_coalesced_frames;
2187         napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
2188
2189         /* disallow changes to fields not explicitly tested above */
2190         if (memcmp(ec, &ec_default, sizeof(ec_default)))
2191                 return -EINVAL;
2192
2193         if (napi_weight ^ vi->sq[0].napi.weight) {
2194                 if (dev->flags & IFF_UP)
2195                         return -EBUSY;
2196                 for (i = 0; i < vi->max_queue_pairs; i++)
2197                         vi->sq[i].napi.weight = napi_weight;
2198         }
2199
2200         return 0;
2201 }
2202
2203 static int virtnet_get_coalesce(struct net_device *dev,
2204                                 struct ethtool_coalesce *ec)
2205 {
2206         struct ethtool_coalesce ec_default = {
2207                 .cmd = ETHTOOL_GCOALESCE,
2208                 .rx_max_coalesced_frames = 1,
2209         };
2210         struct virtnet_info *vi = netdev_priv(dev);
2211
2212         memcpy(ec, &ec_default, sizeof(ec_default));
2213
2214         if (vi->sq[0].napi.weight)
2215                 ec->tx_max_coalesced_frames = 1;
2216
2217         return 0;
2218 }
2219
2220 static void virtnet_init_settings(struct net_device *dev)
2221 {
2222         struct virtnet_info *vi = netdev_priv(dev);
2223
2224         vi->speed = SPEED_UNKNOWN;
2225         vi->duplex = DUPLEX_UNKNOWN;
2226 }
2227
2228 static void virtnet_update_settings(struct virtnet_info *vi)
2229 {
2230         u32 speed;
2231         u8 duplex;
2232
2233         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX))
2234                 return;
2235
2236         speed = virtio_cread32(vi->vdev, offsetof(struct virtio_net_config,
2237                                                   speed));
2238         if (ethtool_validate_speed(speed))
2239                 vi->speed = speed;
2240         duplex = virtio_cread8(vi->vdev, offsetof(struct virtio_net_config,
2241                                                   duplex));
2242         if (ethtool_validate_duplex(duplex))
2243                 vi->duplex = duplex;
2244 }
2245
2246 static const struct ethtool_ops virtnet_ethtool_ops = {
2247         .get_drvinfo = virtnet_get_drvinfo,
2248         .get_link = ethtool_op_get_link,
2249         .get_ringparam = virtnet_get_ringparam,
2250         .get_strings = virtnet_get_strings,
2251         .get_sset_count = virtnet_get_sset_count,
2252         .get_ethtool_stats = virtnet_get_ethtool_stats,
2253         .set_channels = virtnet_set_channels,
2254         .get_channels = virtnet_get_channels,
2255         .get_ts_info = ethtool_op_get_ts_info,
2256         .get_link_ksettings = virtnet_get_link_ksettings,
2257         .set_link_ksettings = virtnet_set_link_ksettings,
2258         .set_coalesce = virtnet_set_coalesce,
2259         .get_coalesce = virtnet_get_coalesce,
2260 };
2261
2262 static void virtnet_freeze_down(struct virtio_device *vdev)
2263 {
2264         struct virtnet_info *vi = vdev->priv;
2265         int i;
2266
2267         /* Make sure no work handler is accessing the device */
2268         flush_work(&vi->config_work);
2269
2270         netif_tx_lock_bh(vi->dev);
2271         netif_device_detach(vi->dev);
2272         netif_tx_unlock_bh(vi->dev);
2273         cancel_delayed_work_sync(&vi->refill);
2274
2275         if (netif_running(vi->dev)) {
2276                 for (i = 0; i < vi->max_queue_pairs; i++) {
2277                         napi_disable(&vi->rq[i].napi);
2278                         virtnet_napi_tx_disable(&vi->sq[i].napi);
2279                 }
2280         }
2281 }
2282
2283 static int init_vqs(struct virtnet_info *vi);
2284
2285 static int virtnet_restore_up(struct virtio_device *vdev)
2286 {
2287         struct virtnet_info *vi = vdev->priv;
2288         int err, i;
2289
2290         err = init_vqs(vi);
2291         if (err)
2292                 return err;
2293
2294         virtio_device_ready(vdev);
2295
2296         if (netif_running(vi->dev)) {
2297                 for (i = 0; i < vi->curr_queue_pairs; i++)
2298                         if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
2299                                 schedule_delayed_work(&vi->refill, 0);
2300
2301                 for (i = 0; i < vi->max_queue_pairs; i++) {
2302                         virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2303                         virtnet_napi_tx_enable(vi, vi->sq[i].vq,
2304                                                &vi->sq[i].napi);
2305                 }
2306         }
2307
2308         netif_tx_lock_bh(vi->dev);
2309         netif_device_attach(vi->dev);
2310         netif_tx_unlock_bh(vi->dev);
2311         return err;
2312 }
2313
2314 static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
2315 {
2316         struct scatterlist sg;
2317         vi->ctrl->offloads = cpu_to_virtio64(vi->vdev, offloads);
2318
2319         sg_init_one(&sg, &vi->ctrl->offloads, sizeof(vi->ctrl->offloads));
2320
2321         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
2322                                   VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
2323                 dev_warn(&vi->dev->dev, "Fail to set guest offload. \n");
2324                 return -EINVAL;
2325         }
2326
2327         return 0;
2328 }
2329
2330 static int virtnet_clear_guest_offloads(struct virtnet_info *vi)
2331 {
2332         u64 offloads = 0;
2333
2334         if (!vi->guest_offloads)
2335                 return 0;
2336
2337         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))
2338                 offloads = 1ULL << VIRTIO_NET_F_GUEST_CSUM;
2339
2340         return virtnet_set_guest_offloads(vi, offloads);
2341 }
2342
2343 static int virtnet_restore_guest_offloads(struct virtnet_info *vi)
2344 {
2345         u64 offloads = vi->guest_offloads;
2346
2347         if (!vi->guest_offloads)
2348                 return 0;
2349         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))
2350                 offloads |= 1ULL << VIRTIO_NET_F_GUEST_CSUM;
2351
2352         return virtnet_set_guest_offloads(vi, offloads);
2353 }
2354
2355 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
2356                            struct netlink_ext_ack *extack)
2357 {
2358         unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
2359         struct virtnet_info *vi = netdev_priv(dev);
2360         struct bpf_prog *old_prog;
2361         u16 xdp_qp = 0, curr_qp;
2362         int i, err;
2363
2364         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)
2365             && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2366                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2367                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
2368                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO))) {
2369                 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing LRO, disable LRO first");
2370                 return -EOPNOTSUPP;
2371         }
2372
2373         if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
2374                 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
2375                 return -EINVAL;
2376         }
2377
2378         if (dev->mtu > max_sz) {
2379                 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
2380                 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
2381                 return -EINVAL;
2382         }
2383
2384         curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
2385         if (prog)
2386                 xdp_qp = nr_cpu_ids;
2387
2388         /* XDP requires extra queues for XDP_TX */
2389         if (curr_qp + xdp_qp > vi->max_queue_pairs) {
2390                 NL_SET_ERR_MSG_MOD(extack, "Too few free TX rings available");
2391                 netdev_warn(dev, "request %i queues but max is %i\n",
2392                             curr_qp + xdp_qp, vi->max_queue_pairs);
2393                 return -ENOMEM;
2394         }
2395
2396         if (prog) {
2397                 prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
2398                 if (IS_ERR(prog))
2399                         return PTR_ERR(prog);
2400         }
2401
2402         /* Make sure NAPI is not using any XDP TX queues for RX. */
2403         if (netif_running(dev))
2404                 for (i = 0; i < vi->max_queue_pairs; i++)
2405                         napi_disable(&vi->rq[i].napi);
2406
2407         netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
2408         err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
2409         if (err)
2410                 goto err;
2411         vi->xdp_queue_pairs = xdp_qp;
2412
2413         for (i = 0; i < vi->max_queue_pairs; i++) {
2414                 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2415                 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
2416                 if (i == 0) {
2417                         if (!old_prog)
2418                                 virtnet_clear_guest_offloads(vi);
2419                         if (!prog)
2420                                 virtnet_restore_guest_offloads(vi);
2421                 }
2422                 if (old_prog)
2423                         bpf_prog_put(old_prog);
2424                 if (netif_running(dev))
2425                         virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2426         }
2427
2428         return 0;
2429
2430 err:
2431         for (i = 0; i < vi->max_queue_pairs; i++)
2432                 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2433         if (prog)
2434                 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
2435         return err;
2436 }
2437
2438 static u32 virtnet_xdp_query(struct net_device *dev)
2439 {
2440         struct virtnet_info *vi = netdev_priv(dev);
2441         const struct bpf_prog *xdp_prog;
2442         int i;
2443
2444         for (i = 0; i < vi->max_queue_pairs; i++) {
2445                 xdp_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2446                 if (xdp_prog)
2447                         return xdp_prog->aux->id;
2448         }
2449         return 0;
2450 }
2451
2452 static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
2453 {
2454         switch (xdp->command) {
2455         case XDP_SETUP_PROG:
2456                 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
2457         case XDP_QUERY_PROG:
2458                 xdp->prog_id = virtnet_xdp_query(dev);
2459                 return 0;
2460         default:
2461                 return -EINVAL;
2462         }
2463 }
2464
2465 static int virtnet_get_phys_port_name(struct net_device *dev, char *buf,
2466                                       size_t len)
2467 {
2468         struct virtnet_info *vi = netdev_priv(dev);
2469         int ret;
2470
2471         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
2472                 return -EOPNOTSUPP;
2473
2474         ret = snprintf(buf, len, "sby");
2475         if (ret >= len)
2476                 return -EOPNOTSUPP;
2477
2478         return 0;
2479 }
2480
2481 static const struct net_device_ops virtnet_netdev = {
2482         .ndo_open            = virtnet_open,
2483         .ndo_stop            = virtnet_close,
2484         .ndo_start_xmit      = start_xmit,
2485         .ndo_validate_addr   = eth_validate_addr,
2486         .ndo_set_mac_address = virtnet_set_mac_address,
2487         .ndo_set_rx_mode     = virtnet_set_rx_mode,
2488         .ndo_get_stats64     = virtnet_stats,
2489         .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
2490         .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
2491         .ndo_bpf                = virtnet_xdp,
2492         .ndo_xdp_xmit           = virtnet_xdp_xmit,
2493         .ndo_features_check     = passthru_features_check,
2494         .ndo_get_phys_port_name = virtnet_get_phys_port_name,
2495 };
2496
2497 static void virtnet_config_changed_work(struct work_struct *work)
2498 {
2499         struct virtnet_info *vi =
2500                 container_of(work, struct virtnet_info, config_work);
2501         u16 v;
2502
2503         if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
2504                                  struct virtio_net_config, status, &v) < 0)
2505                 return;
2506
2507         if (v & VIRTIO_NET_S_ANNOUNCE) {
2508                 netdev_notify_peers(vi->dev);
2509                 virtnet_ack_link_announce(vi);
2510         }
2511
2512         /* Ignore unknown (future) status bits */
2513         v &= VIRTIO_NET_S_LINK_UP;
2514
2515         if (vi->status == v)
2516                 return;
2517
2518         vi->status = v;
2519
2520         if (vi->status & VIRTIO_NET_S_LINK_UP) {
2521                 virtnet_update_settings(vi);
2522                 netif_carrier_on(vi->dev);
2523                 netif_tx_wake_all_queues(vi->dev);
2524         } else {
2525                 netif_carrier_off(vi->dev);
2526                 netif_tx_stop_all_queues(vi->dev);
2527         }
2528 }
2529
2530 static void virtnet_config_changed(struct virtio_device *vdev)
2531 {
2532         struct virtnet_info *vi = vdev->priv;
2533
2534         schedule_work(&vi->config_work);
2535 }
2536
2537 static void virtnet_free_queues(struct virtnet_info *vi)
2538 {
2539         int i;
2540
2541         for (i = 0; i < vi->max_queue_pairs; i++) {
2542                 napi_hash_del(&vi->rq[i].napi);
2543                 netif_napi_del(&vi->rq[i].napi);
2544                 netif_napi_del(&vi->sq[i].napi);
2545         }
2546
2547         /* We called napi_hash_del() before netif_napi_del(),
2548          * we need to respect an RCU grace period before freeing vi->rq
2549          */
2550         synchronize_net();
2551
2552         kfree(vi->rq);
2553         kfree(vi->sq);
2554         kfree(vi->ctrl);
2555 }
2556
2557 static void _free_receive_bufs(struct virtnet_info *vi)
2558 {
2559         struct bpf_prog *old_prog;
2560         int i;
2561
2562         for (i = 0; i < vi->max_queue_pairs; i++) {
2563                 while (vi->rq[i].pages)
2564                         __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
2565
2566                 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2567                 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
2568                 if (old_prog)
2569                         bpf_prog_put(old_prog);
2570         }
2571 }
2572
2573 static void free_receive_bufs(struct virtnet_info *vi)
2574 {
2575         rtnl_lock();
2576         _free_receive_bufs(vi);
2577         rtnl_unlock();
2578 }
2579
2580 static void free_receive_page_frags(struct virtnet_info *vi)
2581 {
2582         int i;
2583         for (i = 0; i < vi->max_queue_pairs; i++)
2584                 if (vi->rq[i].alloc_frag.page)
2585                         put_page(vi->rq[i].alloc_frag.page);
2586 }
2587
2588 static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
2589 {
2590         if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
2591                 return false;
2592         else if (q < vi->curr_queue_pairs)
2593                 return true;
2594         else
2595                 return false;
2596 }
2597
2598 static void free_unused_bufs(struct virtnet_info *vi)
2599 {
2600         void *buf;
2601         int i;
2602
2603         for (i = 0; i < vi->max_queue_pairs; i++) {
2604                 struct virtqueue *vq = vi->sq[i].vq;
2605                 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2606                         if (!is_xdp_raw_buffer_queue(vi, i))
2607                                 dev_kfree_skb(buf);
2608                         else
2609                                 put_page(virt_to_head_page(buf));
2610                 }
2611         }
2612
2613         for (i = 0; i < vi->max_queue_pairs; i++) {
2614                 struct virtqueue *vq = vi->rq[i].vq;
2615
2616                 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2617                         if (vi->mergeable_rx_bufs) {
2618                                 put_page(virt_to_head_page(buf));
2619                         } else if (vi->big_packets) {
2620                                 give_pages(&vi->rq[i], buf);
2621                         } else {
2622                                 put_page(virt_to_head_page(buf));
2623                         }
2624                 }
2625         }
2626 }
2627
2628 static void virtnet_del_vqs(struct virtnet_info *vi)
2629 {
2630         struct virtio_device *vdev = vi->vdev;
2631
2632         virtnet_clean_affinity(vi, -1);
2633
2634         vdev->config->del_vqs(vdev);
2635
2636         virtnet_free_queues(vi);
2637 }
2638
2639 /* How large should a single buffer be so a queue full of these can fit at
2640  * least one full packet?
2641  * Logic below assumes the mergeable buffer header is used.
2642  */
2643 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
2644 {
2645         const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2646         unsigned int rq_size = virtqueue_get_vring_size(vq);
2647         unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
2648         unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
2649         unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
2650
2651         return max(max(min_buf_len, hdr_len) - hdr_len,
2652                    (unsigned int)GOOD_PACKET_LEN);
2653 }
2654
2655 static int virtnet_find_vqs(struct virtnet_info *vi)
2656 {
2657         vq_callback_t **callbacks;
2658         struct virtqueue **vqs;
2659         int ret = -ENOMEM;
2660         int i, total_vqs;
2661         const char **names;
2662         bool *ctx;
2663
2664         /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2665          * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2666          * possible control vq.
2667          */
2668         total_vqs = vi->max_queue_pairs * 2 +
2669                     virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
2670
2671         /* Allocate space for find_vqs parameters */
2672         vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL);
2673         if (!vqs)
2674                 goto err_vq;
2675         callbacks = kmalloc_array(total_vqs, sizeof(*callbacks), GFP_KERNEL);
2676         if (!callbacks)
2677                 goto err_callback;
2678         names = kmalloc_array(total_vqs, sizeof(*names), GFP_KERNEL);
2679         if (!names)
2680                 goto err_names;
2681         if (!vi->big_packets || vi->mergeable_rx_bufs) {
2682                 ctx = kcalloc(total_vqs, sizeof(*ctx), GFP_KERNEL);
2683                 if (!ctx)
2684                         goto err_ctx;
2685         } else {
2686                 ctx = NULL;
2687         }
2688
2689         /* Parameters for control virtqueue, if any */
2690         if (vi->has_cvq) {
2691                 callbacks[total_vqs - 1] = NULL;
2692                 names[total_vqs - 1] = "control";
2693         }
2694
2695         /* Allocate/initialize parameters for send/receive virtqueues */
2696         for (i = 0; i < vi->max_queue_pairs; i++) {
2697                 callbacks[rxq2vq(i)] = skb_recv_done;
2698                 callbacks[txq2vq(i)] = skb_xmit_done;
2699                 sprintf(vi->rq[i].name, "input.%d", i);
2700                 sprintf(vi->sq[i].name, "output.%d", i);
2701                 names[rxq2vq(i)] = vi->rq[i].name;
2702                 names[txq2vq(i)] = vi->sq[i].name;
2703                 if (ctx)
2704                         ctx[rxq2vq(i)] = true;
2705         }
2706
2707         ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
2708                                          names, ctx, NULL);
2709         if (ret)
2710                 goto err_find;
2711
2712         if (vi->has_cvq) {
2713                 vi->cvq = vqs[total_vqs - 1];
2714                 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
2715                         vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2716         }
2717
2718         for (i = 0; i < vi->max_queue_pairs; i++) {
2719                 vi->rq[i].vq = vqs[rxq2vq(i)];
2720                 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
2721                 vi->sq[i].vq = vqs[txq2vq(i)];
2722         }
2723
2724         /* run here: ret == 0. */
2725
2726
2727 err_find:
2728         kfree(ctx);
2729 err_ctx:
2730         kfree(names);
2731 err_names:
2732         kfree(callbacks);
2733 err_callback:
2734         kfree(vqs);
2735 err_vq:
2736         return ret;
2737 }
2738
2739 static int virtnet_alloc_queues(struct virtnet_info *vi)
2740 {
2741         int i;
2742
2743         vi->ctrl = kzalloc(sizeof(*vi->ctrl), GFP_KERNEL);
2744         if (!vi->ctrl)
2745                 goto err_ctrl;
2746         vi->sq = kcalloc(vi->max_queue_pairs, sizeof(*vi->sq), GFP_KERNEL);
2747         if (!vi->sq)
2748                 goto err_sq;
2749         vi->rq = kcalloc(vi->max_queue_pairs, sizeof(*vi->rq), GFP_KERNEL);
2750         if (!vi->rq)
2751                 goto err_rq;
2752
2753         INIT_DELAYED_WORK(&vi->refill, refill_work);
2754         for (i = 0; i < vi->max_queue_pairs; i++) {
2755                 vi->rq[i].pages = NULL;
2756                 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2757                                napi_weight);
2758                 netif_tx_napi_add(vi->dev, &vi->sq[i].napi, virtnet_poll_tx,
2759                                   napi_tx ? napi_weight : 0);
2760
2761                 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2762                 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2763                 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2764
2765                 u64_stats_init(&vi->rq[i].stats.syncp);
2766                 u64_stats_init(&vi->sq[i].stats.syncp);
2767         }
2768
2769         return 0;
2770
2771 err_rq:
2772         kfree(vi->sq);
2773 err_sq:
2774         kfree(vi->ctrl);
2775 err_ctrl:
2776         return -ENOMEM;
2777 }
2778
2779 static int init_vqs(struct virtnet_info *vi)
2780 {
2781         int ret;
2782
2783         /* Allocate send & receive queues */
2784         ret = virtnet_alloc_queues(vi);
2785         if (ret)
2786                 goto err;
2787
2788         ret = virtnet_find_vqs(vi);
2789         if (ret)
2790                 goto err_free;
2791
2792         get_online_cpus();
2793         virtnet_set_affinity(vi);
2794         put_online_cpus();
2795
2796         return 0;
2797
2798 err_free:
2799         virtnet_free_queues(vi);
2800 err:
2801         return ret;
2802 }
2803
2804 #ifdef CONFIG_SYSFS
2805 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2806                 char *buf)
2807 {
2808         struct virtnet_info *vi = netdev_priv(queue->dev);
2809         unsigned int queue_index = get_netdev_rx_queue_index(queue);
2810         unsigned int headroom = virtnet_get_headroom(vi);
2811         unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
2812         struct ewma_pkt_len *avg;
2813
2814         BUG_ON(queue_index >= vi->max_queue_pairs);
2815         avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2816         return sprintf(buf, "%u\n",
2817                        get_mergeable_buf_len(&vi->rq[queue_index], avg,
2818                                        SKB_DATA_ALIGN(headroom + tailroom)));
2819 }
2820
2821 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2822         __ATTR_RO(mergeable_rx_buffer_size);
2823
2824 static struct attribute *virtio_net_mrg_rx_attrs[] = {
2825         &mergeable_rx_buffer_size_attribute.attr,
2826         NULL
2827 };
2828
2829 static const struct attribute_group virtio_net_mrg_rx_group = {
2830         .name = "virtio_net",
2831         .attrs = virtio_net_mrg_rx_attrs
2832 };
2833 #endif
2834
2835 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2836                                     unsigned int fbit,
2837                                     const char *fname, const char *dname)
2838 {
2839         if (!virtio_has_feature(vdev, fbit))
2840                 return false;
2841
2842         dev_err(&vdev->dev, "device advertises feature %s but not %s",
2843                 fname, dname);
2844
2845         return true;
2846 }
2847
2848 #define VIRTNET_FAIL_ON(vdev, fbit, dbit)                       \
2849         virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2850
2851 static bool virtnet_validate_features(struct virtio_device *vdev)
2852 {
2853         if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2854             (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2855                              "VIRTIO_NET_F_CTRL_VQ") ||
2856              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2857                              "VIRTIO_NET_F_CTRL_VQ") ||
2858              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2859                              "VIRTIO_NET_F_CTRL_VQ") ||
2860              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2861              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2862                              "VIRTIO_NET_F_CTRL_VQ"))) {
2863                 return false;
2864         }
2865
2866         return true;
2867 }
2868
2869 #define MIN_MTU ETH_MIN_MTU
2870 #define MAX_MTU ETH_MAX_MTU
2871
2872 static int virtnet_validate(struct virtio_device *vdev)
2873 {
2874         if (!vdev->config->get) {
2875                 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2876                         __func__);
2877                 return -EINVAL;
2878         }
2879
2880         if (!virtnet_validate_features(vdev))
2881                 return -EINVAL;
2882
2883         if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2884                 int mtu = virtio_cread16(vdev,
2885                                          offsetof(struct virtio_net_config,
2886                                                   mtu));
2887                 if (mtu < MIN_MTU)
2888                         __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2889         }
2890
2891         return 0;
2892 }
2893
2894 static int virtnet_probe(struct virtio_device *vdev)
2895 {
2896         int i, err = -ENOMEM;
2897         struct net_device *dev;
2898         struct virtnet_info *vi;
2899         u16 max_queue_pairs;
2900         int mtu;
2901
2902         /* Find if host supports multiqueue virtio_net device */
2903         err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2904                                    struct virtio_net_config,
2905                                    max_virtqueue_pairs, &max_queue_pairs);
2906
2907         /* We need at least 2 queue's */
2908         if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
2909             max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
2910             !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2911                 max_queue_pairs = 1;
2912
2913         /* Allocate ourselves a network device with room for our info */
2914         dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
2915         if (!dev)
2916                 return -ENOMEM;
2917
2918         /* Set up network device as normal. */
2919         dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
2920         dev->netdev_ops = &virtnet_netdev;
2921         dev->features = NETIF_F_HIGHDMA;
2922
2923         dev->ethtool_ops = &virtnet_ethtool_ops;
2924         SET_NETDEV_DEV(dev, &vdev->dev);
2925
2926         /* Do we support "hardware" checksums? */
2927         if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
2928                 /* This opens up the world of extra features. */
2929                 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2930                 if (csum)
2931                         dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2932
2933                 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
2934                         dev->hw_features |= NETIF_F_TSO
2935                                 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
2936                 }
2937                 /* Individual feature bits: what can host handle? */
2938                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
2939                         dev->hw_features |= NETIF_F_TSO;
2940                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
2941                         dev->hw_features |= NETIF_F_TSO6;
2942                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
2943                         dev->hw_features |= NETIF_F_TSO_ECN;
2944
2945                 dev->features |= NETIF_F_GSO_ROBUST;
2946
2947                 if (gso)
2948                         dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
2949                 /* (!csum && gso) case will be fixed by register_netdev() */
2950         }
2951         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
2952                 dev->features |= NETIF_F_RXCSUM;
2953
2954         dev->vlan_features = dev->features;
2955
2956         /* MTU range: 68 - 65535 */
2957         dev->min_mtu = MIN_MTU;
2958         dev->max_mtu = MAX_MTU;
2959
2960         /* Configuration may specify what MAC to use.  Otherwise random. */
2961         if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
2962                 virtio_cread_bytes(vdev,
2963                                    offsetof(struct virtio_net_config, mac),
2964                                    dev->dev_addr, dev->addr_len);
2965         else
2966                 eth_hw_addr_random(dev);
2967
2968         /* Set up our device-specific information */
2969         vi = netdev_priv(dev);
2970         vi->dev = dev;
2971         vi->vdev = vdev;
2972         vdev->priv = vi;
2973
2974         INIT_WORK(&vi->config_work, virtnet_config_changed_work);
2975
2976         /* If we can receive ANY GSO packets, we must allocate large ones. */
2977         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2978             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2979             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
2980             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
2981                 vi->big_packets = true;
2982
2983         if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
2984                 vi->mergeable_rx_bufs = true;
2985
2986         if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
2987             virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2988                 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2989         else
2990                 vi->hdr_len = sizeof(struct virtio_net_hdr);
2991
2992         if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
2993             virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2994                 vi->any_header_sg = true;
2995
2996         if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2997                 vi->has_cvq = true;
2998
2999         if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
3000                 mtu = virtio_cread16(vdev,
3001                                      offsetof(struct virtio_net_config,
3002                                               mtu));
3003                 if (mtu < dev->min_mtu) {
3004                         /* Should never trigger: MTU was previously validated
3005                          * in virtnet_validate.
3006                          */
3007                         dev_err(&vdev->dev, "device MTU appears to have changed "
3008                                 "it is now %d < %d", mtu, dev->min_mtu);
3009                         goto free;
3010                 }
3011
3012                 dev->mtu = mtu;
3013                 dev->max_mtu = mtu;
3014
3015                 /* TODO: size buffers correctly in this case. */
3016                 if (dev->mtu > ETH_DATA_LEN)
3017                         vi->big_packets = true;
3018         }
3019
3020         if (vi->any_header_sg)
3021                 dev->needed_headroom = vi->hdr_len;
3022
3023         /* Enable multiqueue by default */
3024         if (num_online_cpus() >= max_queue_pairs)
3025                 vi->curr_queue_pairs = max_queue_pairs;
3026         else
3027                 vi->curr_queue_pairs = num_online_cpus();
3028         vi->max_queue_pairs = max_queue_pairs;
3029
3030         /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
3031         err = init_vqs(vi);
3032         if (err)
3033                 goto free;
3034
3035 #ifdef CONFIG_SYSFS
3036         if (vi->mergeable_rx_bufs)
3037                 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
3038 #endif
3039         netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
3040         netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
3041
3042         virtnet_init_settings(dev);
3043
3044         if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
3045                 vi->failover = net_failover_create(vi->dev);
3046                 if (IS_ERR(vi->failover)) {
3047                         err = PTR_ERR(vi->failover);
3048                         goto free_vqs;
3049                 }
3050         }
3051
3052         err = register_netdev(dev);
3053         if (err) {
3054                 pr_debug("virtio_net: registering device failed\n");
3055                 goto free_failover;
3056         }
3057
3058         virtio_device_ready(vdev);
3059
3060         err = virtnet_cpu_notif_add(vi);
3061         if (err) {
3062                 pr_debug("virtio_net: registering cpu notifier failed\n");
3063                 goto free_unregister_netdev;
3064         }
3065
3066         virtnet_set_queues(vi, vi->curr_queue_pairs);
3067
3068         /* Assume link up if device can't report link status,
3069            otherwise get link status from config. */
3070         netif_carrier_off(dev);
3071         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
3072                 schedule_work(&vi->config_work);
3073         } else {
3074                 vi->status = VIRTIO_NET_S_LINK_UP;
3075                 virtnet_update_settings(vi);
3076                 netif_carrier_on(dev);
3077         }
3078
3079         for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
3080                 if (virtio_has_feature(vi->vdev, guest_offloads[i]))
3081                         set_bit(guest_offloads[i], &vi->guest_offloads);
3082
3083         pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
3084                  dev->name, max_queue_pairs);
3085
3086         return 0;
3087
3088 free_unregister_netdev:
3089         vi->vdev->config->reset(vdev);
3090
3091         unregister_netdev(dev);
3092 free_failover:
3093         net_failover_destroy(vi->failover);
3094 free_vqs:
3095         cancel_delayed_work_sync(&vi->refill);
3096         free_receive_page_frags(vi);
3097         virtnet_del_vqs(vi);
3098 free:
3099         free_netdev(dev);
3100         return err;
3101 }
3102
3103 static void remove_vq_common(struct virtnet_info *vi)
3104 {
3105         vi->vdev->config->reset(vi->vdev);
3106
3107         /* Free unused buffers in both send and recv, if any. */
3108         free_unused_bufs(vi);
3109
3110         free_receive_bufs(vi);
3111
3112         free_receive_page_frags(vi);
3113
3114         virtnet_del_vqs(vi);
3115 }
3116
3117 static void virtnet_remove(struct virtio_device *vdev)
3118 {
3119         struct virtnet_info *vi = vdev->priv;
3120
3121         virtnet_cpu_notif_remove(vi);
3122
3123         /* Make sure no work handler is accessing the device. */
3124         flush_work(&vi->config_work);
3125
3126         unregister_netdev(vi->dev);
3127
3128         net_failover_destroy(vi->failover);
3129
3130         remove_vq_common(vi);
3131
3132         free_netdev(vi->dev);
3133 }
3134
3135 static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
3136 {
3137         struct virtnet_info *vi = vdev->priv;
3138
3139         virtnet_cpu_notif_remove(vi);
3140         virtnet_freeze_down(vdev);
3141         remove_vq_common(vi);
3142
3143         return 0;
3144 }
3145
3146 static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
3147 {
3148         struct virtnet_info *vi = vdev->priv;
3149         int err;
3150
3151         err = virtnet_restore_up(vdev);
3152         if (err)
3153                 return err;
3154         virtnet_set_queues(vi, vi->curr_queue_pairs);
3155
3156         err = virtnet_cpu_notif_add(vi);
3157         if (err)
3158                 return err;
3159
3160         return 0;
3161 }
3162
3163 static struct virtio_device_id id_table[] = {
3164         { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
3165         { 0 },
3166 };
3167
3168 #define VIRTNET_FEATURES \
3169         VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
3170         VIRTIO_NET_F_MAC, \
3171         VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
3172         VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
3173         VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
3174         VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
3175         VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
3176         VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
3177         VIRTIO_NET_F_CTRL_MAC_ADDR, \
3178         VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
3179         VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY
3180
3181 static unsigned int features[] = {
3182         VIRTNET_FEATURES,
3183 };
3184
3185 static unsigned int features_legacy[] = {
3186         VIRTNET_FEATURES,
3187         VIRTIO_NET_F_GSO,
3188         VIRTIO_F_ANY_LAYOUT,
3189 };
3190
3191 static struct virtio_driver virtio_net_driver = {
3192         .feature_table = features,
3193         .feature_table_size = ARRAY_SIZE(features),
3194         .feature_table_legacy = features_legacy,
3195         .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
3196         .driver.name =  KBUILD_MODNAME,
3197         .driver.owner = THIS_MODULE,
3198         .id_table =     id_table,
3199         .validate =     virtnet_validate,
3200         .probe =        virtnet_probe,
3201         .remove =       virtnet_remove,
3202         .config_changed = virtnet_config_changed,
3203 #ifdef CONFIG_PM_SLEEP
3204         .freeze =       virtnet_freeze,
3205         .restore =      virtnet_restore,
3206 #endif
3207 };
3208
3209 static __init int virtio_net_driver_init(void)
3210 {
3211         int ret;
3212
3213         ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
3214                                       virtnet_cpu_online,
3215                                       virtnet_cpu_down_prep);
3216         if (ret < 0)
3217                 goto out;
3218         virtionet_online = ret;
3219         ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
3220                                       NULL, virtnet_cpu_dead);
3221         if (ret)
3222                 goto err_dead;
3223
3224         ret = register_virtio_driver(&virtio_net_driver);
3225         if (ret)
3226                 goto err_virtio;
3227         return 0;
3228 err_virtio: