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