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/scatterlist.h>
  26 #include <linux/if_vlan.h>
  27 #include <linux/slab.h>
  28 #include <linux/cpu.h>
  29 #include <linux/average.h>
  30
  31 static int napi_weight = NAPI_POLL_WEIGHT;
  32 module_param(napi_weight, int, 0444);
  33
  34 static bool csum = true, gso = true;
  35 module_param(csum, bool, 0444);
  36 module_param(gso, bool, 0444);
  37
  38 /* FIXME: MTU in config. */
  39 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
  40 #define GOOD_COPY_LEN   128
  41
  42 /* Weight used for the RX packet size EWMA. The average packet size is used to
  43  * determine the packet buffer size when refilling RX rings. As the entire RX
  44  * ring may be refilled at once, the weight is chosen so that the EWMA will be
  45  * insensitive to short-term, transient changes in packet size.
  46  */
  47 #define RECEIVE_AVG_WEIGHT 64
  48
  49 /* Minimum alignment for mergeable packet buffers. */
  50 #define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, 256)
  51
  52 #define VIRTNET_DRIVER_VERSION "1.0.0"
  53
  54 struct virtnet_stats {
  55         struct u64_stats_sync tx_syncp;
  56         struct u64_stats_sync rx_syncp;
  57         u64 tx_bytes;
  58         u64 tx_packets;
  59
  60         u64 rx_bytes;
  61         u64 rx_packets;
  62 };
  63
  64 /* Internal representation of a send virtqueue */
  65 struct send_queue {
  66         /* Virtqueue associated with this send _queue */
  67         struct virtqueue *vq;
  68
  69         /* TX: fragments + linear part + virtio header */
  70         struct scatterlist sg[MAX_SKB_FRAGS + 2];
  71
  72         /* Name of the send queue: output.$index */
  73         char name[40];
  74 };
  75
  76 /* Internal representation of a receive virtqueue */
  77 struct receive_queue {
  78         /* Virtqueue associated with this receive_queue */
  79         struct virtqueue *vq;
  80
  81         struct napi_struct napi;
  82
  83         /* Chain pages by the private ptr. */
  84         struct page *pages;
  85
  86         /* Average packet length for mergeable receive buffers. */
  87         struct ewma mrg_avg_pkt_len;
  88
  89         /* Page frag for packet buffer allocation. */
  90         struct page_frag alloc_frag;
  91
  92         /* RX: fragments + linear part + virtio header */
  93         struct scatterlist sg[MAX_SKB_FRAGS + 2];
  94
  95         /* Name of this receive queue: input.$index */
  96         char name[40];
  97 };
  98
  99 struct virtnet_info {
 100         struct virtio_device *vdev;
 101         struct virtqueue *cvq;
 102         struct net_device *dev;
 103         struct send_queue *sq;
 104         struct receive_queue *rq;
 105         unsigned int status;
 106
 107         /* Max # of queue pairs supported by the device */
 108         u16 max_queue_pairs;
 109
 110         /* # of queue pairs currently used by the driver */
 111         u16 curr_queue_pairs;
 112
 113         /* I like... big packets and I cannot lie! */
 114         bool big_packets;
 115
 116         /* Host will merge rx buffers for big packets (shake it! shake it!) */
 117         bool mergeable_rx_bufs;
 118
 119         /* Has control virtqueue */
 120         bool has_cvq;
 121
 122         /* Host can handle any s/g split between our header and packet data */
 123         bool any_header_sg;
 124
 125         /* enable config space updates */
 126         bool config_enable;
 127
 128         /* Active statistics */
 129         struct virtnet_stats __percpu *stats;
 130
 131         /* Work struct for refilling if we run low on memory. */
 132         struct delayed_work refill;
 133
 134         /* Work struct for config space updates */
 135         struct work_struct config_work;
 136
 137         /* Lock for config space updates */
 138         struct mutex config_lock;
 139
 140         /* Does the affinity hint is set for virtqueues? */
 141         bool affinity_hint_set;
 142
 143         /* CPU hot plug notifier */
 144         struct notifier_block nb;
 145 };
 146
 147 struct skb_vnet_hdr {
 148         union {
 149                 struct virtio_net_hdr hdr;
 150                 struct virtio_net_hdr_mrg_rxbuf mhdr;
 151         };
 152 };
 153
 154 struct padded_vnet_hdr {
 155         struct virtio_net_hdr hdr;
 156         /*
 157          * virtio_net_hdr should be in a separated sg buffer because of a
 158          * QEMU bug, and data sg buffer shares same page with this header sg.
 159          * This padding makes next sg 16 byte aligned after virtio_net_hdr.
 160          */
 161         char padding[6];
 162 };
 163
 164 /* Converting between virtqueue no. and kernel tx/rx queue no.
 165  * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
 166  */
 167 static int vq2txq(struct virtqueue *vq)
 168 {
 169         return (vq->index - 1) / 2;
 170 }
 171
 172 static int txq2vq(int txq)
 173 {
 174         return txq * 2 + 1;
 175 }
 176
 177 static int vq2rxq(struct virtqueue *vq)
 178 {
 179         return vq->index / 2;
 180 }
 181
 182 static int rxq2vq(int rxq)
 183 {
 184         return rxq * 2;
 185 }
 186
 187 static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb)
 188 {
 189         return (struct skb_vnet_hdr *)skb->cb;
 190 }
 191
 192 /*
 193  * private is used to chain pages for big packets, put the whole
 194  * most recent used list in the beginning for reuse
 195  */
 196 static void give_pages(struct receive_queue *rq, struct page *page)
 197 {
 198         struct page *end;
 199
 200         /* Find end of list, sew whole thing into vi->rq.pages. */
 201         for (end = page; end->private; end = (struct page *)end->private);
 202         end->private = (unsigned long)rq->pages;
 203         rq->pages = page;
 204 }
 205
 206 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
 207 {
 208         struct page *p = rq->pages;
 209
 210         if (p) {
 211                 rq->pages = (struct page *)p->private;
 212                 /* clear private here, it is used to chain pages */
 213                 p->private = 0;
 214         } else
 215                 p = alloc_page(gfp_mask);
 216         return p;
 217 }
 218
 219 static void skb_xmit_done(struct virtqueue *vq)
 220 {
 221         struct virtnet_info *vi = vq->vdev->priv;
 222
 223         /* Suppress further interrupts. */
 224         virtqueue_disable_cb(vq);
 225
 226         /* We were probably waiting for more output buffers. */
 227         netif_wake_subqueue(vi->dev, vq2txq(vq));
 228 }
 229
 230 static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx)
 231 {
 232         unsigned int truesize = mrg_ctx & (MERGEABLE_BUFFER_ALIGN - 1);
 233         return (truesize + 1) * MERGEABLE_BUFFER_ALIGN;
 234 }
 235
 236 static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx)
 237 {
 238         return (void *)(mrg_ctx & -MERGEABLE_BUFFER_ALIGN);
 239
 240 }
 241
 242 static unsigned long mergeable_buf_to_ctx(void *buf, unsigned int truesize)
 243 {
 244         unsigned int size = truesize / MERGEABLE_BUFFER_ALIGN;
 245         return (unsigned long)buf | (size - 1);
 246 }
 247
 248 /* Called from bottom half context */
 249 static struct sk_buff *page_to_skb(struct receive_queue *rq,
 250                                    struct page *page, unsigned int offset,
 251                                    unsigned int len, unsigned int truesize)
 252 {
 253         struct virtnet_info *vi = rq->vq->vdev->priv;
 254         struct sk_buff *skb;
 255         struct skb_vnet_hdr *hdr;
 256         unsigned int copy, hdr_len, hdr_padded_len;
 257         char *p;
 258
 259         p = page_address(page) + offset;
 260
 261         /* copy small packet so we can reuse these pages for small data */
 262         skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN);
 263         if (unlikely(!skb))
 264                 return NULL;
 265
 266         hdr = skb_vnet_hdr(skb);
 267
 268         if (vi->mergeable_rx_bufs) {
 269                 hdr_len = sizeof hdr->mhdr;
 270                 hdr_padded_len = sizeof hdr->mhdr;
 271         } else {
 272                 hdr_len = sizeof hdr->hdr;
 273                 hdr_padded_len = sizeof(struct padded_vnet_hdr);
 274         }
 275
 276         memcpy(hdr, p, hdr_len);
 277
 278         len -= hdr_len;
 279         offset += hdr_padded_len;
 280         p += hdr_padded_len;
 281
 282         copy = len;
 283         if (copy > skb_tailroom(skb))
 284                 copy = skb_tailroom(skb);
 285         memcpy(skb_put(skb, copy), p, copy);
 286
 287         len -= copy;
 288         offset += copy;
 289
 290         if (vi->mergeable_rx_bufs) {
 291                 if (len)
 292                         skb_add_rx_frag(skb, 0, page, offset, len, truesize);
 293                 else
 294                         put_page(page);
 295                 return skb;
 296         }
 297
 298         /*
 299          * Verify that we can indeed put this data into a skb.
 300          * This is here to handle cases when the device erroneously
 301          * tries to receive more than is possible. This is usually
 302          * the case of a broken device.
 303          */
 304         if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
 305                 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
 306                 dev_kfree_skb(skb);
 307                 return NULL;
 308         }
 309         BUG_ON(offset >= PAGE_SIZE);
 310         while (len) {
 311                 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
 312                 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
 313                                 frag_size, truesize);
 314                 len -= frag_size;
 315                 page = (struct page *)page->private;
 316                 offset = 0;
 317         }
 318
 319         if (page)
 320                 give_pages(rq, page);
 321
 322         return skb;
 323 }
 324
 325 static struct sk_buff *receive_small(void *buf, unsigned int len)
 326 {
 327         struct sk_buff * skb = buf;
 328
 329         len -= sizeof(struct virtio_net_hdr);
 330         skb_trim(skb, len);
 331
 332         return skb;
 333 }
 334
 335 static struct sk_buff *receive_big(struct net_device *dev,
 336                                    struct receive_queue *rq,
 337                                    void *buf,
 338                                    unsigned int len)
 339 {
 340         struct page *page = buf;
 341         struct sk_buff *skb = page_to_skb(rq, page, 0, len, PAGE_SIZE);
 342
 343         if (unlikely(!skb))
 344                 goto err;
 345
 346         return skb;
 347
 348 err:
 349         dev->stats.rx_dropped++;
 350         give_pages(rq, page);
 351         return NULL;
 352 }
 353
 354 static struct sk_buff *receive_mergeable(struct net_device *dev,
 355                                          struct receive_queue *rq,
 356                                          unsigned long ctx,
 357                                          unsigned int len)
 358 {
 359         void *buf = mergeable_ctx_to_buf_address(ctx);
 360         struct skb_vnet_hdr *hdr = buf;
 361         int num_buf = hdr->mhdr.num_buffers;
 362         struct page *page = virt_to_head_page(buf);
 363         int offset = buf - page_address(page);
 364         unsigned int truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
 365
 366         struct sk_buff *head_skb = page_to_skb(rq, page, offset, len, truesize);
 367         struct sk_buff *curr_skb = head_skb;
 368
 369         if (unlikely(!curr_skb))
 370                 goto err_skb;
 371         while (--num_buf) {
 372                 int num_skb_frags;
 373
 374                 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
 375                 if (unlikely(!ctx)) {
 376                         pr_debug("%s: rx error: %d buffers out of %d missing\n",
 377                                  dev->name, num_buf, hdr->mhdr.num_buffers);
 378                         dev->stats.rx_length_errors++;
 379                         goto err_buf;
 380                 }
 381
 382                 buf = mergeable_ctx_to_buf_address(ctx);
 383                 page = virt_to_head_page(buf);
 384
 385                 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
 386                 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
 387                         struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
 388
 389                         if (unlikely(!nskb))
 390                                 goto err_skb;
 391                         if (curr_skb == head_skb)
 392                                 skb_shinfo(curr_skb)->frag_list = nskb;
 393                         else
 394                                 curr_skb->next = nskb;
 395                         curr_skb = nskb;
 396                         head_skb->truesize += nskb->truesize;
 397                         num_skb_frags = 0;
 398                 }
 399                 truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
 400                 if (curr_skb != head_skb) {
 401                         head_skb->data_len += len;
 402                         head_skb->len += len;
 403                         head_skb->truesize += truesize;
 404                 }
 405                 offset = buf - page_address(page);
 406                 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
 407                         put_page(page);
 408                         skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
 409                                              len, truesize);
 410                 } else {
 411                         skb_add_rx_frag(curr_skb, num_skb_frags, page,
 412                                         offset, len, truesize);
 413                 }
 414         }
 415
 416         ewma_add(&rq->mrg_avg_pkt_len, head_skb->len);
 417         return head_skb;
 418
 419 err_skb:
 420         put_page(page);
 421         while (--num_buf) {
 422                 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
 423                 if (unlikely(!ctx)) {
 424                         pr_debug("%s: rx error: %d buffers missing\n",
 425                                  dev->name, num_buf);
 426                         dev->stats.rx_length_errors++;
 427                         break;
 428                 }
 429                 page = virt_to_head_page(mergeable_ctx_to_buf_address(ctx));
 430                 put_page(page);
 431         }
 432 err_buf:
 433         dev->stats.rx_dropped++;
 434         dev_kfree_skb(head_skb);
 435         return NULL;
 436 }
 437
 438 static void receive_buf(struct receive_queue *rq, void *buf, unsigned int len)
 439 {
 440         struct virtnet_info *vi = rq->vq->vdev->priv;
 441         struct net_device *dev = vi->dev;
 442         struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
 443         struct sk_buff *skb;
 444         struct skb_vnet_hdr *hdr;
 445
 446         if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
 447                 pr_debug("%s: short packet %i\n", dev->name, len);
 448                 dev->stats.rx_length_errors++;
 449                 if (vi->mergeable_rx_bufs) {
 450                         unsigned long ctx = (unsigned long)buf;
 451                         void *base = mergeable_ctx_to_buf_address(ctx);
 452                         put_page(virt_to_head_page(base));
 453                 } else if (vi->big_packets) {
 454                         give_pages(rq, buf);
 455                 } else {
 456                         dev_kfree_skb(buf);
 457                 }
 458                 return;
 459         }
 460
 461         if (vi->mergeable_rx_bufs)
 462                 skb = receive_mergeable(dev, rq, (unsigned long)buf, len);
 463         else if (vi->big_packets)
 464                 skb = receive_big(dev, rq, buf, len);
 465         else
 466                 skb = receive_small(buf, len);
 467
 468         if (unlikely(!skb))
 469                 return;
 470
 471         hdr = skb_vnet_hdr(skb);
 472
 473         u64_stats_update_begin(&stats->rx_syncp);
 474         stats->rx_bytes += skb->len;
 475         stats->rx_packets++;
 476         u64_stats_update_end(&stats->rx_syncp);
 477
 478         if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
 479                 pr_debug("Needs csum!\n");
 480                 if (!skb_partial_csum_set(skb,
 481                                           hdr->hdr.csum_start,
 482                                           hdr->hdr.csum_offset))
 483                         goto frame_err;
 484         } else if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID) {
 485                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 486         }
 487
 488         skb->protocol = eth_type_trans(skb, dev);
 489         pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
 490                  ntohs(skb->protocol), skb->len, skb->pkt_type);
 491
 492         if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 493                 pr_debug("GSO!\n");
 494                 switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 495                 case VIRTIO_NET_HDR_GSO_TCPV4:
 496                         skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
 497                         break;
 498                 case VIRTIO_NET_HDR_GSO_UDP:
 499                         skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
 500                         break;
 501                 case VIRTIO_NET_HDR_GSO_TCPV6:
 502                         skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
 503                         break;
 504                 default:
 505                         net_warn_ratelimited("%s: bad gso type %u.\n",
 506                                              dev->name, hdr->hdr.gso_type);
 507                         goto frame_err;
 508                 }
 509
 510                 if (hdr->hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
 511                         skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
 512
 513                 skb_shinfo(skb)->gso_size = hdr->hdr.gso_size;
 514                 if (skb_shinfo(skb)->gso_size == 0) {
 515                         net_warn_ratelimited("%s: zero gso size.\n", dev->name);
 516                         goto frame_err;
 517                 }
 518
 519                 /* Header must be checked, and gso_segs computed. */
 520                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
 521                 skb_shinfo(skb)->gso_segs = 0;
 522         }
 523
 524         netif_receive_skb(skb);
 525         return;
 526
 527 frame_err:
 528         dev->stats.rx_frame_errors++;
 529         dev_kfree_skb(skb);
 530 }
 531
 532 static int add_recvbuf_small(struct receive_queue *rq, gfp_t gfp)
 533 {
 534         struct virtnet_info *vi = rq->vq->vdev->priv;
 535         struct sk_buff *skb;
 536         struct skb_vnet_hdr *hdr;
 537         int err;
 538
 539         skb = __netdev_alloc_skb_ip_align(vi->dev, GOOD_PACKET_LEN, gfp);
 540         if (unlikely(!skb))
 541                 return -ENOMEM;
 542
 543         skb_put(skb, GOOD_PACKET_LEN);
 544
 545         hdr = skb_vnet_hdr(skb);
 546         sg_set_buf(rq->sg, &hdr->hdr, sizeof hdr->hdr);
 547
 548         skb_to_sgvec(skb, rq->sg + 1, 0, skb->len);
 549
 550         err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp);
 551         if (err < 0)
 552                 dev_kfree_skb(skb);
 553
 554         return err;
 555 }
 556
 557 static int add_recvbuf_big(struct receive_queue *rq, gfp_t gfp)
 558 {
 559         struct page *first, *list = NULL;
 560         char *p;
 561         int i, err, offset;
 562
 563         /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
 564         for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
 565                 first = get_a_page(rq, gfp);
 566                 if (!first) {
 567                         if (list)
 568                                 give_pages(rq, list);
 569                         return -ENOMEM;
 570                 }
 571                 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
 572
 573                 /* chain new page in list head to match sg */
 574                 first->private = (unsigned long)list;
 575                 list = first;
 576         }
 577
 578         first = get_a_page(rq, gfp);
 579         if (!first) {
 580                 give_pages(rq, list);
 581                 return -ENOMEM;
 582         }
 583         p = page_address(first);
 584
 585         /* rq->sg[0], rq->sg[1] share the same page */
 586         /* a separated rq->sg[0] for virtio_net_hdr only due to QEMU bug */
 587         sg_set_buf(&rq->sg[0], p, sizeof(struct virtio_net_hdr));
 588
 589         /* rq->sg[1] for data packet, from offset */
 590         offset = sizeof(struct padded_vnet_hdr);
 591         sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
 592
 593         /* chain first in list head */
 594         first->private = (unsigned long)list;
 595         err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
 596                                   first, gfp);
 597         if (err < 0)
 598                 give_pages(rq, first);
 599
 600         return err;
 601 }
 602
 603 static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp)
 604 {
 605         const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
 606         struct page_frag *alloc_frag = &rq->alloc_frag;
 607         char *buf;
 608         unsigned long ctx;
 609         int err;
 610         unsigned int len, hole;
 611
 612         len = hdr_len + clamp_t(unsigned int, ewma_read(&rq->mrg_avg_pkt_len),
 613                                 GOOD_PACKET_LEN, PAGE_SIZE - hdr_len);
 614         len = ALIGN(len, MERGEABLE_BUFFER_ALIGN);
 615         if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
 616                 return -ENOMEM;
 617
 618         buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
 619         ctx = mergeable_buf_to_ctx(buf, len);
 620         get_page(alloc_frag->page);
 621         alloc_frag->offset += len;
 622         hole = alloc_frag->size - alloc_frag->offset;
 623         if (hole < len) {
 624                 /* To avoid internal fragmentation, if there is very likely not
 625                  * enough space for another buffer, add the remaining space to
 626                  * the current buffer. This extra space is not included in
 627                  * the truesize stored in ctx.
 628                  */
 629                 len += hole;
 630                 alloc_frag->offset += hole;
 631         }
 632
 633         sg_init_one(rq->sg, buf, len);
 634         err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, (void *)ctx, gfp);
 635         if (err < 0)
 636                 put_page(virt_to_head_page(buf));
 637
 638         return err;
 639 }
 640
 641 /*
 642  * Returns false if we couldn't fill entirely (OOM).
 643  *
 644  * Normally run in the receive path, but can also be run from ndo_open
 645  * before we're receiving packets, or from refill_work which is
 646  * careful to disable receiving (using napi_disable).
 647  */
 648 static bool try_fill_recv(struct receive_queue *rq, gfp_t gfp)
 649 {
 650         struct virtnet_info *vi = rq->vq->vdev->priv;
 651         int err;
 652         bool oom;
 653
 654         gfp |= __GFP_COLD;
 655         do {
 656                 if (vi->mergeable_rx_bufs)
 657                         err = add_recvbuf_mergeable(rq, gfp);
 658                 else if (vi->big_packets)
 659                         err = add_recvbuf_big(rq, gfp);
 660                 else
 661                         err = add_recvbuf_small(rq, gfp);
 662
 663                 oom = err == -ENOMEM;
 664                 if (err)
 665                         break;
 666         } while (rq->vq->num_free);
 667         if (unlikely(!virtqueue_kick(rq->vq)))
 668                 return false;
 669         return !oom;
 670 }
 671
 672 static void skb_recv_done(struct virtqueue *rvq)
 673 {
 674         struct virtnet_info *vi = rvq->vdev->priv;
 675         struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
 676
 677         /* Schedule NAPI, Suppress further interrupts if successful. */
 678         if (napi_schedule_prep(&rq->napi)) {
 679                 virtqueue_disable_cb(rvq);
 680                 __napi_schedule(&rq->napi);
 681         }
 682 }
 683
 684 static void virtnet_napi_enable(struct receive_queue *rq)
 685 {
 686         napi_enable(&rq->napi);
 687
 688         /* If all buffers were filled by other side before we napi_enabled, we
 689          * won't get another interrupt, so process any outstanding packets
 690          * now.  virtnet_poll wants re-enable the queue, so we disable here.
 691          * We synchronize against interrupts via NAPI_STATE_SCHED */
 692         if (napi_schedule_prep(&rq->napi)) {
 693                 virtqueue_disable_cb(rq->vq);
 694                 local_bh_disable();
 695                 __napi_schedule(&rq->napi);
 696                 local_bh_enable();
 697         }
 698 }
 699
 700 static void refill_work(struct work_struct *work)
 701 {
 702         struct virtnet_info *vi =
 703                 container_of(work, struct virtnet_info, refill.work);
 704         bool still_empty;
 705         int i;
 706
 707         for (i = 0; i < vi->curr_queue_pairs; i++) {
 708                 struct receive_queue *rq = &vi->rq[i];
 709
 710                 napi_disable(&rq->napi);
 711                 still_empty = !try_fill_recv(rq, GFP_KERNEL);
 712                 virtnet_napi_enable(rq);
 713
 714                 /* In theory, this can happen: if we don't get any buffers in
 715                  * we will *never* try to fill again.
 716                  */
 717                 if (still_empty)
 718                         schedule_delayed_work(&vi->refill, HZ/2);
 719         }
 720 }
 721
 722 static int virtnet_poll(struct napi_struct *napi, int budget)
 723 {
 724         struct receive_queue *rq =
 725                 container_of(napi, struct receive_queue, napi);
 726         struct virtnet_info *vi = rq->vq->vdev->priv;
 727         void *buf;
 728         unsigned int r, len, received = 0;
 729
 730 again:
 731         while (received < budget &&
 732                (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
 733                 receive_buf(rq, buf, len);
 734                 received++;
 735         }
 736
 737         if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
 738                 if (!try_fill_recv(rq, GFP_ATOMIC))
 739                         schedule_delayed_work(&vi->refill, 0);
 740         }
 741
 742         /* Out of packets? */
 743         if (received < budget) {
 744                 r = virtqueue_enable_cb_prepare(rq->vq);
 745                 napi_complete(napi);
 746                 if (unlikely(virtqueue_poll(rq->vq, r)) &&
 747                     napi_schedule_prep(napi)) {
 748                         virtqueue_disable_cb(rq->vq);
 749                         __napi_schedule(napi);
 750                         goto again;
 751                 }
 752         }
 753
 754         return received;
 755 }
 756
 757 static int virtnet_open(struct net_device *dev)
 758 {
 759         struct virtnet_info *vi = netdev_priv(dev);
 760         int i;
 761
 762         for (i = 0; i < vi->max_queue_pairs; i++) {
 763                 if (i < vi->curr_queue_pairs)
 764                         /* Make sure we have some buffers: if oom use wq. */
 765                         if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
 766                                 schedule_delayed_work(&vi->refill, 0);
 767                 virtnet_napi_enable(&vi->rq[i]);
 768         }
 769
 770         return 0;
 771 }
 772
 773 static void free_old_xmit_skbs(struct send_queue *sq)
 774 {
 775         struct sk_buff *skb;
 776         unsigned int len;
 777         struct virtnet_info *vi = sq->vq->vdev->priv;
 778         struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
 779
 780         while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
 781                 pr_debug("Sent skb %p\n", skb);
 782
 783                 u64_stats_update_begin(&stats->tx_syncp);
 784                 stats->tx_bytes += skb->len;
 785                 stats->tx_packets++;
 786                 u64_stats_update_end(&stats->tx_syncp);
 787
 788                 dev_kfree_skb_any(skb);
 789         }
 790 }
 791
 792 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
 793 {
 794         struct skb_vnet_hdr *hdr;
 795         const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
 796         struct virtnet_info *vi = sq->vq->vdev->priv;
 797         unsigned num_sg;
 798         unsigned hdr_len;
 799         bool can_push;
 800
 801         pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
 802         if (vi->mergeable_rx_bufs)
 803                 hdr_len = sizeof hdr->mhdr;
 804         else
 805                 hdr_len = sizeof hdr->hdr;
 806
 807         can_push = vi->any_header_sg &&
 808                 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
 809                 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
 810         /* Even if we can, don't push here yet as this would skew
 811          * csum_start offset below. */
 812         if (can_push)
 813                 hdr = (struct skb_vnet_hdr *)(skb->data - hdr_len);
 814         else
 815                 hdr = skb_vnet_hdr(skb);
 816
 817         if (skb->ip_summed == CHECKSUM_PARTIAL) {
 818                 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 819                 hdr->hdr.csum_start = skb_checksum_start_offset(skb);
 820                 hdr->hdr.csum_offset = skb->csum_offset;
 821         } else {
 822                 hdr->hdr.flags = 0;
 823                 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
 824         }
 825
 826         if (skb_is_gso(skb)) {
 827                 hdr->hdr.hdr_len = skb_headlen(skb);
 828                 hdr->hdr.gso_size = skb_shinfo(skb)->gso_size;
 829                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
 830                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
 831                 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
 832                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
 833                 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 834                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
 835                 else
 836                         BUG();
 837                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
 838                         hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
 839         } else {
 840                 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
 841                 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
 842         }
 843
 844         if (vi->mergeable_rx_bufs)
 845                 hdr->mhdr.num_buffers = 0;
 846
 847         if (can_push) {
 848                 __skb_push(skb, hdr_len);
 849                 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
 850                 /* Pull header back to avoid skew in tx bytes calculations. */
 851                 __skb_pull(skb, hdr_len);
 852         } else {
 853                 sg_set_buf(sq->sg, hdr, hdr_len);
 854                 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
 855         }
 856         return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
 857 }
 858
 859 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 860 {
 861         struct virtnet_info *vi = netdev_priv(dev);
 862         int qnum = skb_get_queue_mapping(skb);
 863         struct send_queue *sq = &vi->sq[qnum];
 864         int err;
 865
 866         /* Free up any pending old buffers before queueing new ones. */
 867         free_old_xmit_skbs(sq);
 868
 869         /* Try to transmit */
 870         err = xmit_skb(sq, skb);
 871
 872         /* This should not happen! */
 873         if (unlikely(err) || unlikely(!virtqueue_kick(sq->vq))) {
 874                 dev->stats.tx_fifo_errors++;
 875                 if (net_ratelimit())
 876                         dev_warn(&dev->dev,
 877                                  "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
 878                 dev->stats.tx_dropped++;
 879                 kfree_skb(skb);
 880                 return NETDEV_TX_OK;
 881         }
 882
 883         /* Don't wait up for transmitted skbs to be freed. */
 884         skb_orphan(skb);
 885         nf_reset(skb);
 886
 887         /* Apparently nice girls don't return TX_BUSY; stop the queue
 888          * before it gets out of hand.  Naturally, this wastes entries. */
 889         if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
 890                 netif_stop_subqueue(dev, qnum);
 891                 if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
 892                         /* More just got used, free them then recheck. */
 893                         free_old_xmit_skbs(sq);
 894                         if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
 895                                 netif_start_subqueue(dev, qnum);
 896                                 virtqueue_disable_cb(sq->vq);
 897                         }
 898                 }
 899         }
 900
 901         return NETDEV_TX_OK;
 902 }
 903
 904 /*
 905  * Send command via the control virtqueue and check status.  Commands
 906  * supported by the hypervisor, as indicated by feature bits, should
 907  * never fail unless improperly formatted.
 908  */
 909 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
 910                                  struct scatterlist *out)
 911 {
 912         struct scatterlist *sgs[4], hdr, stat;
 913         struct virtio_net_ctrl_hdr ctrl;
 914         virtio_net_ctrl_ack status = ~0;
 915         unsigned out_num = 0, tmp;
 916
 917         /* Caller should know better */
 918         BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
 919
 920         ctrl.class = class;
 921         ctrl.cmd = cmd;
 922         /* Add header */
 923         sg_init_one(&hdr, &ctrl, sizeof(ctrl));
 924         sgs[out_num++] = &hdr;
 925
 926         if (out)
 927                 sgs[out_num++] = out;
 928
 929         /* Add return status. */
 930         sg_init_one(&stat, &status, sizeof(status));
 931         sgs[out_num] = &stat;
 932
 933         BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
 934         BUG_ON(virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC) < 0);
 935
 936         if (unlikely(!virtqueue_kick(vi->cvq)))
 937                 return status == VIRTIO_NET_OK;
 938
 939         /* Spin for a response, the kick causes an ioport write, trapping
 940          * into the hypervisor, so the request should be handled immediately.
 941          */
 942         while (!virtqueue_get_buf(vi->cvq, &tmp) &&
 943                !virtqueue_is_broken(vi->cvq))
 944                 cpu_relax();
 945
 946         return status == VIRTIO_NET_OK;
 947 }
 948
 949 static int virtnet_set_mac_address(struct net_device *dev, void *p)
 950 {
 951         struct virtnet_info *vi = netdev_priv(dev);
 952         struct virtio_device *vdev = vi->vdev;
 953         int ret;
 954         struct sockaddr *addr = p;
 955         struct scatterlist sg;
 956
 957         ret = eth_prepare_mac_addr_change(dev, p);
 958         if (ret)
 959                 return ret;
 960
 961         if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
 962                 sg_init_one(&sg, addr->sa_data, dev->addr_len);
 963                 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
 964                                           VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
 965                         dev_warn(&vdev->dev,
 966                                  "Failed to set mac address by vq command.\n");
 967                         return -EINVAL;
 968                 }
 969         } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
 970                 unsigned int i;
 971
 972                 /* Naturally, this has an atomicity problem. */
 973                 for (i = 0; i < dev->addr_len; i++)
 974                         virtio_cwrite8(vdev,
 975                                        offsetof(struct virtio_net_config, mac) +
 976                                        i, addr->sa_data[i]);
 977         }
 978
 979         eth_commit_mac_addr_change(dev, p);
 980
 981         return 0;
 982 }
 983
 984 static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev,
 985                                                struct rtnl_link_stats64 *tot)
 986 {
 987         struct virtnet_info *vi = netdev_priv(dev);
 988         int cpu;
 989         unsigned int start;
 990
 991         for_each_possible_cpu(cpu) {
 992                 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
 993                 u64 tpackets, tbytes, rpackets, rbytes;
 994
 995                 do {
 996                         start = u64_stats_fetch_begin_bh(&stats->tx_syncp);
 997                         tpackets = stats->tx_packets;
 998                         tbytes   = stats->tx_bytes;
 999                 } while (u64_stats_fetch_retry_bh(&stats->tx_syncp, start));
1000
1001                 do {
1002                         start = u64_stats_fetch_begin_bh(&stats->rx_syncp);
1003                         rpackets = stats->rx_packets;
1004                         rbytes   = stats->rx_bytes;
1005                 } while (u64_stats_fetch_retry_bh(&stats->rx_syncp, start));
1006
1007                 tot->rx_packets += rpackets;
1008                 tot->tx_packets += tpackets;
1009                 tot->rx_bytes   += rbytes;
1010                 tot->tx_bytes   += tbytes;
1011         }
1012
1013         tot->tx_dropped = dev->stats.tx_dropped;
1014         tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1015         tot->rx_dropped = dev->stats.rx_dropped;
1016         tot->rx_length_errors = dev->stats.rx_length_errors;
1017         tot->rx_frame_errors = dev->stats.rx_frame_errors;
1018
1019         return tot;
1020 }
1021
1022 #ifdef CONFIG_NET_POLL_CONTROLLER
1023 static void virtnet_netpoll(struct net_device *dev)
1024 {
1025         struct virtnet_info *vi = netdev_priv(dev);
1026         int i;
1027
1028         for (i = 0; i < vi->curr_queue_pairs; i++)
1029                 napi_schedule(&vi->rq[i].napi);
1030 }
1031 #endif
1032
1033 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1034 {
1035         rtnl_lock();
1036         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1037                                   VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1038                 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1039         rtnl_unlock();
1040 }
1041
1042 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1043 {
1044         struct scatterlist sg;
1045         struct virtio_net_ctrl_mq s;
1046         struct net_device *dev = vi->dev;
1047
1048         if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1049                 return 0;
1050
1051         s.virtqueue_pairs = queue_pairs;
1052         sg_init_one(&sg, &s, sizeof(s));
1053
1054         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1055                                   VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1056                 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1057                          queue_pairs);
1058                 return -EINVAL;
1059         } else {
1060                 vi->curr_queue_pairs = queue_pairs;
1061                 /* virtnet_open() will refill when device is going to up. */
1062                 if (dev->flags & IFF_UP)
1063                         schedule_delayed_work(&vi->refill, 0);
1064         }
1065
1066         return 0;
1067 }
1068
1069 static int virtnet_close(struct net_device *dev)
1070 {
1071         struct virtnet_info *vi = netdev_priv(dev);
1072         int i;
1073
1074         /* Make sure refill_work doesn't re-enable napi! */
1075         cancel_delayed_work_sync(&vi->refill);
1076
1077         for (i = 0; i < vi->max_queue_pairs; i++)
1078                 napi_disable(&vi->rq[i].napi);
1079
1080         return 0;
1081 }
1082
1083 static void virtnet_set_rx_mode(struct net_device *dev)
1084 {
1085         struct virtnet_info *vi = netdev_priv(dev);
1086         struct scatterlist sg[2];
1087         u8 promisc, allmulti;
1088         struct virtio_net_ctrl_mac *mac_data;
1089         struct netdev_hw_addr *ha;
1090         int uc_count;
1091         int mc_count;
1092         void *buf;
1093         int i;
1094
1095         /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1096         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1097                 return;
1098
1099         promisc = ((dev->flags & IFF_PROMISC) != 0);
1100         allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1101
1102         sg_init_one(sg, &promisc, sizeof(promisc));
1103
1104         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1105                                   VIRTIO_NET_CTRL_RX_PROMISC, sg))
1106                 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1107                          promisc ? "en" : "dis");
1108
1109         sg_init_one(sg, &allmulti, sizeof(allmulti));
1110
1111         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1112                                   VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1113                 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1114                          allmulti ? "en" : "dis");
1115
1116         uc_count = netdev_uc_count(dev);
1117         mc_count = netdev_mc_count(dev);
1118         /* MAC filter - use one buffer for both lists */
1119         buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1120                       (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1121         mac_data = buf;
1122         if (!buf)
1123                 return;
1124
1125         sg_init_table(sg, 2);
1126
1127         /* Store the unicast list and count in the front of the buffer */
1128         mac_data->entries = uc_count;
1129         i = 0;
1130         netdev_for_each_uc_addr(ha, dev)
1131                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1132
1133         sg_set_buf(&sg[0], mac_data,
1134                    sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1135
1136         /* multicast list and count fill the end */
1137         mac_data = (void *)&mac_data->macs[uc_count][0];
1138
1139         mac_data->entries = mc_count;
1140         i = 0;
1141         netdev_for_each_mc_addr(ha, dev)
1142                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1143
1144         sg_set_buf(&sg[1], mac_data,
1145                    sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1146
1147         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1148                                   VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1149                 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1150
1151         kfree(buf);
1152 }
1153
1154 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1155                                    __be16 proto, u16 vid)
1156 {
1157         struct virtnet_info *vi = netdev_priv(dev);
1158         struct scatterlist sg;
1159
1160         sg_init_one(&sg, &vid, sizeof(vid));
1161
1162         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1163                                   VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1164                 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1165         return 0;
1166 }
1167
1168 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1169                                     __be16 proto, u16 vid)
1170 {
1171         struct virtnet_info *vi = netdev_priv(dev);
1172         struct scatterlist sg;
1173
1174         sg_init_one(&sg, &vid, sizeof(vid));
1175
1176         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1177                                   VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1178                 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1179         return 0;
1180 }
1181
1182 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1183 {
1184         int i;
1185
1186         if (vi->affinity_hint_set) {
1187                 for (i = 0; i < vi->max_queue_pairs; i++) {
1188                         virtqueue_set_affinity(vi->rq[i].vq, -1);
1189                         virtqueue_set_affinity(vi->sq[i].vq, -1);
1190                 }
1191
1192                 vi->affinity_hint_set = false;
1193         }
1194 }
1195
1196 static void virtnet_set_affinity(struct virtnet_info *vi)
1197 {
1198         int i;
1199         int cpu;
1200
1201         /* In multiqueue mode, when the number of cpu is equal to the number of
1202          * queue pairs, we let the queue pairs to be private to one cpu by
1203          * setting the affinity hint to eliminate the contention.
1204          */
1205         if (vi->curr_queue_pairs == 1 ||
1206             vi->max_queue_pairs != num_online_cpus()) {
1207                 virtnet_clean_affinity(vi, -1);
1208                 return;
1209         }
1210
1211         i = 0;
1212         for_each_online_cpu(cpu) {
1213                 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1214                 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1215                 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1216                 i++;
1217         }
1218
1219         vi->affinity_hint_set = true;
1220 }
1221
1222 static int virtnet_cpu_callback(struct notifier_block *nfb,
1223                                 unsigned long action, void *hcpu)
1224 {
1225         struct virtnet_info *vi = container_of(nfb, struct virtnet_info, nb);
1226
1227         switch(action & ~CPU_TASKS_FROZEN) {
1228         case CPU_ONLINE:
1229         case CPU_DOWN_FAILED:
1230         case CPU_DEAD:
1231                 virtnet_set_affinity(vi);
1232                 break;
1233         case CPU_DOWN_PREPARE:
1234                 virtnet_clean_affinity(vi, (long)hcpu);
1235                 break;
1236         default:
1237                 break;
1238         }
1239
1240         return NOTIFY_OK;
1241 }
1242
1243 static void virtnet_get_ringparam(struct net_device *dev,
1244                                 struct ethtool_ringparam *ring)
1245 {
1246         struct virtnet_info *vi = netdev_priv(dev);
1247
1248         ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1249         ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1250         ring->rx_pending = ring->rx_max_pending;
1251         ring->tx_pending = ring->tx_max_pending;
1252 }
1253
1254
1255 static void virtnet_get_drvinfo(struct net_device *dev,
1256                                 struct ethtool_drvinfo *info)
1257 {
1258         struct virtnet_info *vi = netdev_priv(dev);
1259         struct virtio_device *vdev = vi->vdev;
1260
1261         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1262         strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1263         strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1264
1265 }
1266
1267 /* TODO: Eliminate OOO packets during switching */
1268 static int virtnet_set_channels(struct net_device *dev,
1269                                 struct ethtool_channels *channels)
1270 {
1271         struct virtnet_info *vi = netdev_priv(dev);
1272         u16 queue_pairs = channels->combined_count;
1273         int err;
1274
1275         /* We don't support separate rx/tx channels.
1276          * We don't allow setting 'other' channels.
1277          */
1278         if (channels->rx_count || channels->tx_count || channels->other_count)
1279                 return -EINVAL;
1280
1281         if (queue_pairs > vi->max_queue_pairs)
1282                 return -EINVAL;
1283
1284         get_online_cpus();
1285         err = virtnet_set_queues(vi, queue_pairs);
1286         if (!err) {
1287                 netif_set_real_num_tx_queues(dev, queue_pairs);
1288                 netif_set_real_num_rx_queues(dev, queue_pairs);
1289
1290                 virtnet_set_affinity(vi);
1291         }
1292         put_online_cpus();
1293
1294         return err;
1295 }
1296
1297 static void virtnet_get_channels(struct net_device *dev,
1298                                  struct ethtool_channels *channels)
1299 {
1300         struct virtnet_info *vi = netdev_priv(dev);
1301
1302         channels->combined_count = vi->curr_queue_pairs;
1303         channels->max_combined = vi->max_queue_pairs;
1304         channels->max_other = 0;
1305         channels->rx_count = 0;
1306         channels->tx_count = 0;
1307         channels->other_count = 0;
1308 }
1309
1310 static const struct ethtool_ops virtnet_ethtool_ops = {
1311         .get_drvinfo = virtnet_get_drvinfo,
1312         .get_link = ethtool_op_get_link,
1313         .get_ringparam = virtnet_get_ringparam,
1314         .set_channels = virtnet_set_channels,
1315         .get_channels = virtnet_get_channels,
1316 };
1317
1318 #define MIN_MTU 68
1319 #define MAX_MTU 65535
1320
1321 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
1322 {
1323         if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
1324                 return -EINVAL;
1325         dev->mtu = new_mtu;
1326         return 0;
1327 }
1328
1329 static const struct net_device_ops virtnet_netdev = {
1330         .ndo_open            = virtnet_open,
1331         .ndo_stop            = virtnet_close,
1332         .ndo_start_xmit      = start_xmit,
1333         .ndo_validate_addr   = eth_validate_addr,
1334         .ndo_set_mac_address = virtnet_set_mac_address,
1335         .ndo_set_rx_mode     = virtnet_set_rx_mode,
1336         .ndo_change_mtu      = virtnet_change_mtu,
1337         .ndo_get_stats64     = virtnet_stats,
1338         .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
1339         .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
1340 #ifdef CONFIG_NET_POLL_CONTROLLER
1341         .ndo_poll_controller = virtnet_netpoll,
1342 #endif
1343 };
1344
1345 static void virtnet_config_changed_work(struct work_struct *work)
1346 {
1347         struct virtnet_info *vi =
1348                 container_of(work, struct virtnet_info, config_work);
1349         u16 v;
1350
1351         mutex_lock(&vi->config_lock);
1352         if (!vi->config_enable)
1353                 goto done;
1354
1355         if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
1356                                  struct virtio_net_config, status, &v) < 0)
1357                 goto done;
1358
1359         if (v & VIRTIO_NET_S_ANNOUNCE) {
1360                 netdev_notify_peers(vi->dev);
1361                 virtnet_ack_link_announce(vi);
1362         }
1363
1364         /* Ignore unknown (future) status bits */
1365         v &= VIRTIO_NET_S_LINK_UP;
1366
1367         if (vi->status == v)
1368                 goto done;
1369
1370         vi->status = v;
1371
1372         if (vi->status & VIRTIO_NET_S_LINK_UP) {
1373                 netif_carrier_on(vi->dev);
1374                 netif_tx_wake_all_queues(vi->dev);
1375         } else {
1376                 netif_carrier_off(vi->dev);
1377                 netif_tx_stop_all_queues(vi->dev);
1378         }
1379 done:
1380         mutex_unlock(&vi->config_lock);
1381 }
1382
1383 static void virtnet_config_changed(struct virtio_device *vdev)
1384 {
1385         struct virtnet_info *vi = vdev->priv;
1386
1387         schedule_work(&vi->config_work);
1388 }
1389
1390 static void virtnet_free_queues(struct virtnet_info *vi)
1391 {
1392         int i;
1393
1394         for (i = 0; i < vi->max_queue_pairs; i++)
1395                 netif_napi_del(&vi->rq[i].napi);
1396
1397         kfree(vi->rq);
1398         kfree(vi->sq);
1399 }
1400
1401 static void free_receive_bufs(struct virtnet_info *vi)
1402 {
1403         int i;
1404
1405         for (i = 0; i < vi->max_queue_pairs; i++) {
1406                 while (vi->rq[i].pages)
1407                         __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
1408         }
1409 }
1410
1411 static void free_receive_page_frags(struct virtnet_info *vi)
1412 {
1413         int i;
1414         for (i = 0; i < vi->max_queue_pairs; i++)
1415                 if (vi->rq[i].alloc_frag.page)
1416                         put_page(vi->rq[i].alloc_frag.page);
1417 }
1418
1419 static void free_unused_bufs(struct virtnet_info *vi)
1420 {
1421         void *buf;
1422         int i;
1423
1424         for (i = 0; i < vi->max_queue_pairs; i++) {
1425                 struct virtqueue *vq = vi->sq[i].vq;
1426                 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
1427                         dev_kfree_skb(buf);
1428         }
1429
1430         for (i = 0; i < vi->max_queue_pairs; i++) {
1431                 struct virtqueue *vq = vi->rq[i].vq;
1432
1433                 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
1434                         if (vi->mergeable_rx_bufs) {
1435                                 unsigned long ctx = (unsigned long)buf;
1436                                 void *base = mergeable_ctx_to_buf_address(ctx);
1437                                 put_page(virt_to_head_page(base));
1438                         } else if (vi->big_packets) {
1439                                 give_pages(&vi->rq[i], buf);
1440                         } else {
1441                                 dev_kfree_skb(buf);
1442                         }
1443                 }
1444         }
1445 }
1446
1447 static void virtnet_del_vqs(struct virtnet_info *vi)
1448 {
1449         struct virtio_device *vdev = vi->vdev;
1450
1451         virtnet_clean_affinity(vi, -1);
1452
1453         vdev->config->del_vqs(vdev);
1454
1455         virtnet_free_queues(vi);
1456 }
1457
1458 static int virtnet_find_vqs(struct virtnet_info *vi)
1459 {
1460         vq_callback_t **callbacks;
1461         struct virtqueue **vqs;
1462         int ret = -ENOMEM;
1463         int i, total_vqs;
1464         const char **names;
1465
1466         /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
1467          * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
1468          * possible control vq.
1469          */
1470         total_vqs = vi->max_queue_pairs * 2 +
1471                     virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
1472
1473         /* Allocate space for find_vqs parameters */
1474         vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
1475         if (!vqs)
1476                 goto err_vq;
1477         callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
1478         if (!callbacks)
1479                 goto err_callback;
1480         names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
1481         if (!names)
1482                 goto err_names;
1483
1484         /* Parameters for control virtqueue, if any */
1485         if (vi->has_cvq) {
1486                 callbacks[total_vqs - 1] = NULL;
1487                 names[total_vqs - 1] = "control";
1488         }
1489
1490         /* Allocate/initialize parameters for send/receive virtqueues */
1491         for (i = 0; i < vi->max_queue_pairs; i++) {
1492                 callbacks[rxq2vq(i)] = skb_recv_done;
1493                 callbacks[txq2vq(i)] = skb_xmit_done;
1494                 sprintf(vi->rq[i].name, "input.%d", i);
1495                 sprintf(vi->sq[i].name, "output.%d", i);
1496                 names[rxq2vq(i)] = vi->rq[i].name;
1497                 names[txq2vq(i)] = vi->sq[i].name;
1498         }
1499
1500         ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
1501                                          names);
1502         if (ret)
1503                 goto err_find;
1504
1505         if (vi->has_cvq) {
1506                 vi->cvq = vqs[total_vqs - 1];
1507                 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
1508                         vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
1509         }
1510
1511         for (i = 0; i < vi->max_queue_pairs; i++) {
1512                 vi->rq[i].vq = vqs[rxq2vq(i)];
1513                 vi->sq[i].vq = vqs[txq2vq(i)];
1514         }
1515
1516         kfree(names);
1517         kfree(callbacks);
1518         kfree(vqs);
1519
1520         return 0;
1521
1522 err_find:
1523         kfree(names);
1524 err_names:
1525         kfree(callbacks);
1526 err_callback:
1527         kfree(vqs);
1528 err_vq:
1529         return ret;
1530 }
1531
1532 static int virtnet_alloc_queues(struct virtnet_info *vi)
1533 {
1534         int i;
1535
1536         vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
1537         if (!vi->sq)
1538                 goto err_sq;
1539         vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
1540         if (!vi->rq)
1541                 goto err_rq;
1542
1543         INIT_DELAYED_WORK(&vi->refill, refill_work);
1544         for (i = 0; i < vi->max_queue_pairs; i++) {
1545                 vi->rq[i].pages = NULL;
1546                 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
1547                                napi_weight);
1548
1549                 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
1550                 ewma_init(&vi->rq[i].mrg_avg_pkt_len, 1, RECEIVE_AVG_WEIGHT);
1551                 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
1552         }
1553
1554         return 0;
1555
1556 err_rq:
1557         kfree(vi->sq);
1558 err_sq:
1559         return -ENOMEM;
1560 }
1561
1562 static int init_vqs(struct virtnet_info *vi)
1563 {
1564         int ret;
1565
1566         /* Allocate send & receive queues */
1567         ret = virtnet_alloc_queues(vi);
1568         if (ret)
1569                 goto err;
1570
1571         ret = virtnet_find_vqs(vi);
1572         if (ret)
1573                 goto err_free;
1574
1575         get_online_cpus();
1576         virtnet_set_affinity(vi);
1577         put_online_cpus();
1578
1579         return 0;
1580
1581 err_free:
1582         virtnet_free_queues(vi);
1583 err:
1584         return ret;
1585 }
1586
1587 static int virtnet_probe(struct virtio_device *vdev)
1588 {
1589         int i, err;
1590         struct net_device *dev;
1591         struct virtnet_info *vi;
1592         u16 max_queue_pairs;
1593
1594         /* Find if host supports multiqueue virtio_net device */
1595         err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
1596                                    struct virtio_net_config,
1597                                    max_virtqueue_pairs, &max_queue_pairs);
1598
1599         /* We need at least 2 queue's */
1600         if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
1601             max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
1602             !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
1603                 max_queue_pairs = 1;
1604
1605         /* Allocate ourselves a network device with room for our info */
1606         dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
1607         if (!dev)
1608                 return -ENOMEM;
1609
1610         /* Set up network device as normal. */
1611         dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
1612         dev->netdev_ops = &virtnet_netdev;
1613         dev->features = NETIF_F_HIGHDMA;
1614
1615         SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
1616         SET_NETDEV_DEV(dev, &vdev->dev);
1617
1618         /* Do we support "hardware" checksums? */
1619         if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
1620                 /* This opens up the world of extra features. */
1621                 dev->hw_features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1622                 if (csum)
1623                         dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1624
1625                 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
1626                         dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
1627                                 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
1628                 }
1629                 /* Individual feature bits: what can host handle? */
1630                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
1631                         dev->hw_features |= NETIF_F_TSO;
1632                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
1633                         dev->hw_features |= NETIF_F_TSO6;
1634                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
1635                         dev->hw_features |= NETIF_F_TSO_ECN;
1636                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
1637                         dev->hw_features |= NETIF_F_UFO;
1638
1639                 if (gso)
1640                         dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
1641                 /* (!csum && gso) case will be fixed by register_netdev() */
1642         }
1643         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
1644                 dev->features |= NETIF_F_RXCSUM;
1645
1646         dev->vlan_features = dev->features;
1647
1648         /* Configuration may specify what MAC to use.  Otherwise random. */
1649         if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
1650                 virtio_cread_bytes(vdev,
1651                                    offsetof(struct virtio_net_config, mac),
1652                                    dev->dev_addr, dev->addr_len);
1653         else
1654                 eth_hw_addr_random(dev);
1655
1656         /* Set up our device-specific information */
1657         vi = netdev_priv(dev);
1658         vi->dev = dev;
1659         vi->vdev = vdev;
1660         vdev->priv = vi;
1661         vi->stats = alloc_percpu(struct virtnet_stats);
1662         err = -ENOMEM;
1663         if (vi->stats == NULL)
1664                 goto free;
1665
1666         for_each_possible_cpu(i) {
1667                 struct virtnet_stats *virtnet_stats;
1668                 virtnet_stats = per_cpu_ptr(vi->stats, i);
1669                 u64_stats_init(&virtnet_stats->tx_syncp);
1670                 u64_stats_init(&virtnet_stats->rx_syncp);
1671         }
1672
1673         mutex_init(&vi->config_lock);
1674         vi->config_enable = true;
1675         INIT_WORK(&vi->config_work, virtnet_config_changed_work);
1676
1677         /* If we can receive ANY GSO packets, we must allocate large ones. */
1678         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1679             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1680             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
1681                 vi->big_packets = true;
1682
1683         if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
1684                 vi->mergeable_rx_bufs = true;
1685
1686         if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT))
1687                 vi->any_header_sg = true;
1688
1689         if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
1690                 vi->has_cvq = true;
1691
1692         /* Use single tx/rx queue pair as default */
1693         vi->curr_queue_pairs = 1;
1694         vi->max_queue_pairs = max_queue_pairs;
1695
1696         /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
1697         err = init_vqs(vi);
1698         if (err)
1699                 goto free_stats;
1700
1701         netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
1702         netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
1703
1704         err = register_netdev(dev);
1705         if (err) {
1706                 pr_debug("virtio_net: registering device failed\n");
1707                 goto free_vqs;
1708         }
1709
1710         /* Last of all, set up some receive buffers. */
1711         for (i = 0; i < vi->curr_queue_pairs; i++) {
1712                 try_fill_recv(&vi->rq[i], GFP_KERNEL);
1713
1714                 /* If we didn't even get one input buffer, we're useless. */
1715                 if (vi->rq[i].vq->num_free ==
1716                     virtqueue_get_vring_size(vi->rq[i].vq)) {
1717                         free_unused_bufs(vi);
1718                         err = -ENOMEM;
1719                         goto free_recv_bufs;
1720                 }
1721         }
1722
1723         vi->nb.notifier_call = &virtnet_cpu_callback;
1724         err = register_hotcpu_notifier(&vi->nb);
1725         if (err) {
1726                 pr_debug("virtio_net: registering cpu notifier failed\n");
1727                 goto free_recv_bufs;
1728         }
1729
1730         /* Assume link up if device can't report link status,
1731            otherwise get link status from config. */
1732         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
1733                 netif_carrier_off(dev);
1734                 schedule_work(&vi->config_work);
1735         } else {
1736                 vi->status = VIRTIO_NET_S_LINK_UP;
1737                 netif_carrier_on(dev);
1738         }
1739
1740         pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
1741                  dev->name, max_queue_pairs);
1742
1743         return 0;
1744
1745 free_recv_bufs:
1746         free_receive_bufs(vi);
1747         unregister_netdev(dev);
1748 free_vqs:
1749         cancel_delayed_work_sync(&vi->refill);
1750         free_receive_page_frags(vi);
1751         virtnet_del_vqs(vi);
1752 free_stats:
1753         free_percpu(vi->stats);
1754 free:
1755         free_netdev(dev);
1756         return err;
1757 }
1758
1759 static void remove_vq_common(struct virtnet_info *vi)
1760 {
1761         vi->vdev->config->reset(vi->vdev);
1762
1763         /* Free unused buffers in both send and recv, if any. */
1764         free_unused_bufs(vi);
1765
1766         free_receive_bufs(vi);
1767
1768         free_receive_page_frags(vi);
1769
1770         virtnet_del_vqs(vi);
1771 }
1772
1773 static void virtnet_remove(struct virtio_device *vdev)
1774 {
1775         struct virtnet_info *vi = vdev->priv;
1776
1777         unregister_hotcpu_notifier(&vi->nb);
1778
1779         /* Prevent config work handler from accessing the device. */
1780         mutex_lock(&vi->config_lock);
1781         vi->config_enable = false;
1782         mutex_unlock(&vi->config_lock);
1783
1784         unregister_netdev(vi->dev);
1785
1786         remove_vq_common(vi);
1787
1788         flush_work(&vi->config_work);
1789
1790         free_percpu(vi->stats);
1791         free_netdev(vi->dev);
1792 }
1793
1794 #ifdef CONFIG_PM_SLEEP
1795 static int virtnet_freeze(struct virtio_device *vdev)
1796 {
1797         struct virtnet_info *vi = vdev->priv;
1798         int i;
1799
1800         unregister_hotcpu_notifier(&vi->nb);
1801
1802         /* Prevent config work handler from accessing the device */
1803         mutex_lock(&vi->config_lock);
1804         vi->config_enable = false;
1805         mutex_unlock(&vi->config_lock);
1806
1807         netif_device_detach(vi->dev);
1808         cancel_delayed_work_sync(&vi->refill);
1809
1810         if (netif_running(vi->dev))
1811                 for (i = 0; i < vi->max_queue_pairs; i++) {
1812                         napi_disable(&vi->rq[i].napi);
1813                         netif_napi_del(&vi->rq[i].napi);
1814                 }
1815
1816         remove_vq_common(vi);
1817
1818         flush_work(&vi->config_work);
1819
1820         return 0;
1821 }
1822
1823 static int virtnet_restore(struct virtio_device *vdev)
1824 {
1825         struct virtnet_info *vi = vdev->priv;
1826         int err, i;
1827
1828         err = init_vqs(vi);
1829         if (err)
1830                 return err;
1831
1832         if (netif_running(vi->dev)) {
1833                 for (i = 0; i < vi->curr_queue_pairs; i++)
1834                         if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
1835                                 schedule_delayed_work(&vi->refill, 0);
1836
1837                 for (i = 0; i < vi->max_queue_pairs; i++)
1838                         virtnet_napi_enable(&vi->rq[i]);
1839         }
1840
1841         netif_device_attach(vi->dev);
1842
1843         mutex_lock(&vi->config_lock);
1844         vi->config_enable = true;
1845         mutex_unlock(&vi->config_lock);
1846
1847         rtnl_lock();
1848         virtnet_set_queues(vi, vi->curr_queue_pairs);
1849         rtnl_unlock();
1850
1851         err = register_hotcpu_notifier(&vi->nb);
1852         if (err)
1853                 return err;
1854
1855         return 0;
1856 }
1857 #endif
1858
1859 static struct virtio_device_id id_table[] = {
1860         { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
1861         { 0 },
1862 };
1863
1864 static unsigned int features[] = {
1865         VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
1866         VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
1867         VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
1868         VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
1869         VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
1870         VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
1871         VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
1872         VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ,
1873         VIRTIO_NET_F_CTRL_MAC_ADDR,
1874         VIRTIO_F_ANY_LAYOUT,
1875 };
1876
1877 static struct virtio_driver virtio_net_driver = {
1878         .feature_table = features,
1879         .feature_table_size = ARRAY_SIZE(features),
1880         .driver.name =  KBUILD_MODNAME,
1881         .driver.owner = THIS_MODULE,
1882         .id_table =     id_table,
1883         .probe =        virtnet_probe,
1884         .remove =       virtnet_remove,
1885         .config_changed = virtnet_config_changed,
1886 #ifdef CONFIG_PM_SLEEP
1887         .freeze =       virtnet_freeze,
1888         .restore =      virtnet_restore,
1889 #endif
1890 };
1891
1892 module_virtio_driver(virtio_net_driver);
1893
1894 MODULE_DEVICE_TABLE(virtio, id_table);
1895 MODULE_DESCRIPTION("Virtio network driver");
1896 MODULE_LICENSE("GPL");