drivers/net/virtio_net.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* A network driver using virtio.
   3  *
   4  * Copyright 2007 Rusty Russell <[email protected]> IBM Corporation
   5  */
   6 //#define DEBUG
   7 #include <linux/netdevice.h>
   8 #include <linux/etherdevice.h>
   9 #include <linux/ethtool.h>
  10 #include <linux/module.h>
  11 #include <linux/virtio.h>
  12 #include <linux/virtio_net.h>
  13 #include <linux/bpf.h>
  14 #include <linux/bpf_trace.h>
  15 #include <linux/scatterlist.h>
  16 #include <linux/if_vlan.h>
  17 #include <linux/slab.h>
  18 #include <linux/cpu.h>
  19 #include <linux/average.h>
  20 #include <linux/filter.h>
  21 #include <linux/kernel.h>
  22 #include <net/route.h>
  23 #include <net/xdp.h>
  24 #include <net/net_failover.h>
  25
  26 static int napi_weight = NAPI_POLL_WEIGHT;
  27 module_param(napi_weight, int, 0444);
  28
  29 static bool csum = true, gso = true, napi_tx = true;
  30 module_param(csum, bool, 0444);
  31 module_param(gso, bool, 0444);
  32 module_param(napi_tx, bool, 0644);
  33
  34 /* FIXME: MTU in config. */
  35 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
  36 #define GOOD_COPY_LEN   128
  37
  38 #define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
  39
  40 /* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
  41 #define VIRTIO_XDP_HEADROOM 256
  42
  43 /* Separating two types of XDP xmit */
  44 #define VIRTIO_XDP_TX           BIT(0)
  45 #define VIRTIO_XDP_REDIR        BIT(1)
  46
  47 #define VIRTIO_XDP_FLAG BIT(0)
  48
  49 /* RX packet size EWMA. The average packet size is used to determine the packet
  50  * buffer size when refilling RX rings. As the entire RX ring may be refilled
  51  * at once, the weight is chosen so that the EWMA will be insensitive to short-
  52  * term, transient changes in packet size.
  53  */
  54 DECLARE_EWMA(pkt_len, 0, 64)
  55
  56 #define VIRTNET_DRIVER_VERSION "1.0.0"
  57
  58 static const unsigned long guest_offloads[] = {
  59         VIRTIO_NET_F_GUEST_TSO4,
  60         VIRTIO_NET_F_GUEST_TSO6,
  61         VIRTIO_NET_F_GUEST_ECN,
  62         VIRTIO_NET_F_GUEST_UFO,
  63         VIRTIO_NET_F_GUEST_CSUM,
  64         VIRTIO_NET_F_GUEST_USO4,
  65         VIRTIO_NET_F_GUEST_USO6,
  66         VIRTIO_NET_F_GUEST_HDRLEN
  67 };
  68
  69 #define GUEST_OFFLOAD_GRO_HW_MASK ((1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
  70                                 (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
  71                                 (1ULL << VIRTIO_NET_F_GUEST_ECN)  | \
  72                                 (1ULL << VIRTIO_NET_F_GUEST_UFO)  | \
  73                                 (1ULL << VIRTIO_NET_F_GUEST_USO4) | \
  74                                 (1ULL << VIRTIO_NET_F_GUEST_USO6))
  75
  76 struct virtnet_stat_desc {
  77         char desc[ETH_GSTRING_LEN];
  78         size_t offset;
  79 };
  80
  81 struct virtnet_sq_stats {
  82         struct u64_stats_sync syncp;
  83         u64 packets;
  84         u64 bytes;
  85         u64 xdp_tx;
  86         u64 xdp_tx_drops;
  87         u64 kicks;
  88         u64 tx_timeouts;
  89 };
  90
  91 struct virtnet_rq_stats {
  92         struct u64_stats_sync syncp;
  93         u64 packets;
  94         u64 bytes;
  95         u64 drops;
  96         u64 xdp_packets;
  97         u64 xdp_tx;
  98         u64 xdp_redirects;
  99         u64 xdp_drops;
 100         u64 kicks;
 101 };
 102
 103 #define VIRTNET_SQ_STAT(m)      offsetof(struct virtnet_sq_stats, m)
 104 #define VIRTNET_RQ_STAT(m)      offsetof(struct virtnet_rq_stats, m)
 105
 106 static const struct virtnet_stat_desc virtnet_sq_stats_desc[] = {
 107         { "packets",            VIRTNET_SQ_STAT(packets) },
 108         { "bytes",              VIRTNET_SQ_STAT(bytes) },
 109         { "xdp_tx",             VIRTNET_SQ_STAT(xdp_tx) },
 110         { "xdp_tx_drops",       VIRTNET_SQ_STAT(xdp_tx_drops) },
 111         { "kicks",              VIRTNET_SQ_STAT(kicks) },
 112         { "tx_timeouts",        VIRTNET_SQ_STAT(tx_timeouts) },
 113 };
 114
 115 static const struct virtnet_stat_desc virtnet_rq_stats_desc[] = {
 116         { "packets",            VIRTNET_RQ_STAT(packets) },
 117         { "bytes",              VIRTNET_RQ_STAT(bytes) },
 118         { "drops",              VIRTNET_RQ_STAT(drops) },
 119         { "xdp_packets",        VIRTNET_RQ_STAT(xdp_packets) },
 120         { "xdp_tx",             VIRTNET_RQ_STAT(xdp_tx) },
 121         { "xdp_redirects",      VIRTNET_RQ_STAT(xdp_redirects) },
 122         { "xdp_drops",          VIRTNET_RQ_STAT(xdp_drops) },
 123         { "kicks",              VIRTNET_RQ_STAT(kicks) },
 124 };
 125
 126 #define VIRTNET_SQ_STATS_LEN    ARRAY_SIZE(virtnet_sq_stats_desc)
 127 #define VIRTNET_RQ_STATS_LEN    ARRAY_SIZE(virtnet_rq_stats_desc)
 128
 129 /* Internal representation of a send virtqueue */
 130 struct send_queue {
 131         /* Virtqueue associated with this send _queue */
 132         struct virtqueue *vq;
 133
 134         /* TX: fragments + linear part + virtio header */
 135         struct scatterlist sg[MAX_SKB_FRAGS + 2];
 136
 137         /* Name of the send queue: output.$index */
 138         char name[16];
 139
 140         struct virtnet_sq_stats stats;
 141
 142         struct napi_struct napi;
 143
 144         /* Record whether sq is in reset state. */
 145         bool reset;
 146 };
 147
 148 /* Internal representation of a receive virtqueue */
 149 struct receive_queue {
 150         /* Virtqueue associated with this receive_queue */
 151         struct virtqueue *vq;
 152
 153         struct napi_struct napi;
 154
 155         struct bpf_prog __rcu *xdp_prog;
 156
 157         struct virtnet_rq_stats stats;
 158
 159         /* Chain pages by the private ptr. */
 160         struct page *pages;
 161
 162         /* Average packet length for mergeable receive buffers. */
 163         struct ewma_pkt_len mrg_avg_pkt_len;
 164
 165         /* Page frag for packet buffer allocation. */
 166         struct page_frag alloc_frag;
 167
 168         /* RX: fragments + linear part + virtio header */
 169         struct scatterlist sg[MAX_SKB_FRAGS + 2];
 170
 171         /* Min single buffer size for mergeable buffers case. */
 172         unsigned int min_buf_len;
 173
 174         /* Name of this receive queue: input.$index */
 175         char name[16];
 176
 177         struct xdp_rxq_info xdp_rxq;
 178 };
 179
 180 /* This structure can contain rss message with maximum settings for indirection table and keysize
 181  * Note, that default structure that describes RSS configuration virtio_net_rss_config
 182  * contains same info but can't handle table values.
 183  * In any case, structure would be passed to virtio hw through sg_buf split by parts
 184  * because table sizes may be differ according to the device configuration.
 185  */
 186 #define VIRTIO_NET_RSS_MAX_KEY_SIZE     40
 187 #define VIRTIO_NET_RSS_MAX_TABLE_LEN    128
 188 struct virtio_net_ctrl_rss {
 189         u32 hash_types;
 190         u16 indirection_table_mask;
 191         u16 unclassified_queue;
 192         u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN];
 193         u16 max_tx_vq;
 194         u8 hash_key_length;
 195         u8 key[VIRTIO_NET_RSS_MAX_KEY_SIZE];
 196 };
 197
 198 /* Control VQ buffers: protected by the rtnl lock */
 199 struct control_buf {
 200         struct virtio_net_ctrl_hdr hdr;
 201         virtio_net_ctrl_ack status;
 202         struct virtio_net_ctrl_mq mq;
 203         u8 promisc;
 204         u8 allmulti;
 205         __virtio16 vid;
 206         __virtio64 offloads;
 207         struct virtio_net_ctrl_rss rss;
 208 };
 209
 210 struct virtnet_info {
 211         struct virtio_device *vdev;
 212         struct virtqueue *cvq;
 213         struct net_device *dev;
 214         struct send_queue *sq;
 215         struct receive_queue *rq;
 216         unsigned int status;
 217
 218         /* Max # of queue pairs supported by the device */
 219         u16 max_queue_pairs;
 220
 221         /* # of queue pairs currently used by the driver */
 222         u16 curr_queue_pairs;
 223
 224         /* # of XDP queue pairs currently used by the driver */
 225         u16 xdp_queue_pairs;
 226
 227         /* xdp_queue_pairs may be 0, when xdp is already loaded. So add this. */
 228         bool xdp_enabled;
 229
 230         /* I like... big packets and I cannot lie! */
 231         bool big_packets;
 232
 233         /* number of sg entries allocated for big packets */
 234         unsigned int big_packets_num_skbfrags;
 235
 236         /* Host will merge rx buffers for big packets (shake it! shake it!) */
 237         bool mergeable_rx_bufs;
 238
 239         /* Host supports rss and/or hash report */
 240         bool has_rss;
 241         bool has_rss_hash_report;
 242         u8 rss_key_size;
 243         u16 rss_indir_table_size;
 244         u32 rss_hash_types_supported;
 245         u32 rss_hash_types_saved;
 246
 247         /* Has control virtqueue */
 248         bool has_cvq;
 249
 250         /* Host can handle any s/g split between our header and packet data */
 251         bool any_header_sg;
 252
 253         /* Packet virtio header size */
 254         u8 hdr_len;
 255
 256         /* Work struct for delayed refilling if we run low on memory. */
 257         struct delayed_work refill;
 258
 259         /* Is delayed refill enabled? */
 260         bool refill_enabled;
 261
 262         /* The lock to synchronize the access to refill_enabled */
 263         spinlock_t refill_lock;
 264
 265         /* Work struct for config space updates */
 266         struct work_struct config_work;
 267
 268         /* Does the affinity hint is set for virtqueues? */
 269         bool affinity_hint_set;
 270
 271         /* CPU hotplug instances for online & dead */
 272         struct hlist_node node;
 273         struct hlist_node node_dead;
 274
 275         struct control_buf *ctrl;
 276
 277         /* Ethtool settings */
 278         u8 duplex;
 279         u32 speed;
 280
 281         /* Interrupt coalescing settings */
 282         u32 tx_usecs;
 283         u32 rx_usecs;
 284         u32 tx_max_packets;
 285         u32 rx_max_packets;
 286
 287         unsigned long guest_offloads;
 288         unsigned long guest_offloads_capable;
 289
 290         /* failover when STANDBY feature enabled */
 291         struct failover *failover;
 292 };
 293
 294 struct padded_vnet_hdr {
 295         struct virtio_net_hdr_v1_hash hdr;
 296         /*
 297          * hdr is in a separate sg buffer, and data sg buffer shares same page
 298          * with this header sg. This padding makes next sg 16 byte aligned
 299          * after the header.
 300          */
 301         char padding[12];
 302 };
 303
 304 static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf);
 305 static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf);
 306
 307 static bool is_xdp_frame(void *ptr)
 308 {
 309         return (unsigned long)ptr & VIRTIO_XDP_FLAG;
 310 }
 311
 312 static void *xdp_to_ptr(struct xdp_frame *ptr)
 313 {
 314         return (void *)((unsigned long)ptr | VIRTIO_XDP_FLAG);
 315 }
 316
 317 static struct xdp_frame *ptr_to_xdp(void *ptr)
 318 {
 319         return (struct xdp_frame *)((unsigned long)ptr & ~VIRTIO_XDP_FLAG);
 320 }
 321
 322 /* Converting between virtqueue no. and kernel tx/rx queue no.
 323  * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
 324  */
 325 static int vq2txq(struct virtqueue *vq)
 326 {
 327         return (vq->index - 1) / 2;
 328 }
 329
 330 static int txq2vq(int txq)
 331 {
 332         return txq * 2 + 1;
 333 }
 334
 335 static int vq2rxq(struct virtqueue *vq)
 336 {
 337         return vq->index / 2;
 338 }
 339
 340 static int rxq2vq(int rxq)
 341 {
 342         return rxq * 2;
 343 }
 344
 345 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
 346 {
 347         return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
 348 }
 349
 350 /*
 351  * private is used to chain pages for big packets, put the whole
 352  * most recent used list in the beginning for reuse
 353  */
 354 static void give_pages(struct receive_queue *rq, struct page *page)
 355 {
 356         struct page *end;
 357
 358         /* Find end of list, sew whole thing into vi->rq.pages. */
 359         for (end = page; end->private; end = (struct page *)end->private);
 360         end->private = (unsigned long)rq->pages;
 361         rq->pages = page;
 362 }
 363
 364 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
 365 {
 366         struct page *p = rq->pages;
 367
 368         if (p) {
 369                 rq->pages = (struct page *)p->private;
 370                 /* clear private here, it is used to chain pages */
 371                 p->private = 0;
 372         } else
 373                 p = alloc_page(gfp_mask);
 374         return p;
 375 }
 376
 377 static void enable_delayed_refill(struct virtnet_info *vi)
 378 {
 379         spin_lock_bh(&vi->refill_lock);
 380         vi->refill_enabled = true;
 381         spin_unlock_bh(&vi->refill_lock);
 382 }
 383
 384 static void disable_delayed_refill(struct virtnet_info *vi)
 385 {
 386         spin_lock_bh(&vi->refill_lock);
 387         vi->refill_enabled = false;
 388         spin_unlock_bh(&vi->refill_lock);
 389 }
 390
 391 static void virtqueue_napi_schedule(struct napi_struct *napi,
 392                                     struct virtqueue *vq)
 393 {
 394         if (napi_schedule_prep(napi)) {
 395                 virtqueue_disable_cb(vq);
 396                 __napi_schedule(napi);
 397         }
 398 }
 399
 400 static void virtqueue_napi_complete(struct napi_struct *napi,
 401                                     struct virtqueue *vq, int processed)
 402 {
 403         int opaque;
 404
 405         opaque = virtqueue_enable_cb_prepare(vq);
 406         if (napi_complete_done(napi, processed)) {
 407                 if (unlikely(virtqueue_poll(vq, opaque)))
 408                         virtqueue_napi_schedule(napi, vq);
 409         } else {
 410                 virtqueue_disable_cb(vq);
 411         }
 412 }
 413
 414 static void skb_xmit_done(struct virtqueue *vq)
 415 {
 416         struct virtnet_info *vi = vq->vdev->priv;
 417         struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
 418
 419         /* Suppress further interrupts. */
 420         virtqueue_disable_cb(vq);
 421
 422         if (napi->weight)
 423                 virtqueue_napi_schedule(napi, vq);
 424         else
 425                 /* We were probably waiting for more output buffers. */
 426                 netif_wake_subqueue(vi->dev, vq2txq(vq));
 427 }
 428
 429 #define MRG_CTX_HEADER_SHIFT 22
 430 static void *mergeable_len_to_ctx(unsigned int truesize,
 431                                   unsigned int headroom)
 432 {
 433         return (void *)(unsigned long)((headroom << MRG_CTX_HEADER_SHIFT) | truesize);
 434 }
 435
 436 static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx)
 437 {
 438         return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT;
 439 }
 440
 441 static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx)
 442 {
 443         return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1);
 444 }
 445
 446 /* Called from bottom half context */
 447 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
 448                                    struct receive_queue *rq,
 449                                    struct page *page, unsigned int offset,
 450                                    unsigned int len, unsigned int truesize,
 451                                    unsigned int headroom)
 452 {
 453         struct sk_buff *skb;
 454         struct virtio_net_hdr_mrg_rxbuf *hdr;
 455         unsigned int copy, hdr_len, hdr_padded_len;
 456         struct page *page_to_free = NULL;
 457         int tailroom, shinfo_size;
 458         char *p, *hdr_p, *buf;
 459
 460         p = page_address(page) + offset;
 461         hdr_p = p;
 462
 463         hdr_len = vi->hdr_len;
 464         if (vi->mergeable_rx_bufs)
 465                 hdr_padded_len = hdr_len;
 466         else
 467                 hdr_padded_len = sizeof(struct padded_vnet_hdr);
 468
 469         buf = p - headroom;
 470         len -= hdr_len;
 471         offset += hdr_padded_len;
 472         p += hdr_padded_len;
 473         tailroom = truesize - headroom  - hdr_padded_len - len;
 474
 475         shinfo_size = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 476
 477         /* copy small packet so we can reuse these pages */
 478         if (!NET_IP_ALIGN && len > GOOD_COPY_LEN && tailroom >= shinfo_size) {
 479                 skb = build_skb(buf, truesize);
 480                 if (unlikely(!skb))
 481                         return NULL;
 482
 483                 skb_reserve(skb, p - buf);
 484                 skb_put(skb, len);
 485
 486                 page = (struct page *)page->private;
 487                 if (page)
 488                         give_pages(rq, page);
 489                 goto ok;
 490         }
 491
 492         /* copy small packet so we can reuse these pages for small data */
 493         skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
 494         if (unlikely(!skb))
 495                 return NULL;
 496
 497         /* Copy all frame if it fits skb->head, otherwise
 498          * we let virtio_net_hdr_to_skb() and GRO pull headers as needed.
 499          */
 500         if (len <= skb_tailroom(skb))
 501                 copy = len;
 502         else
 503                 copy = ETH_HLEN;
 504         skb_put_data(skb, p, copy);
 505
 506         len -= copy;
 507         offset += copy;
 508
 509         if (vi->mergeable_rx_bufs) {
 510                 if (len)
 511                         skb_add_rx_frag(skb, 0, page, offset, len, truesize);
 512                 else
 513                         page_to_free = page;
 514                 goto ok;
 515         }
 516
 517         /*
 518          * Verify that we can indeed put this data into a skb.
 519          * This is here to handle cases when the device erroneously
 520          * tries to receive more than is possible. This is usually
 521          * the case of a broken device.
 522          */
 523         if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
 524                 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
 525                 dev_kfree_skb(skb);
 526                 return NULL;
 527         }
 528         BUG_ON(offset >= PAGE_SIZE);
 529         while (len) {
 530                 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
 531                 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
 532                                 frag_size, truesize);
 533                 len -= frag_size;
 534                 page = (struct page *)page->private;
 535                 offset = 0;
 536         }
 537
 538         if (page)
 539                 give_pages(rq, page);
 540
 541 ok:
 542         hdr = skb_vnet_hdr(skb);
 543         memcpy(hdr, hdr_p, hdr_len);
 544         if (page_to_free)
 545                 put_page(page_to_free);
 546
 547         return skb;
 548 }
 549
 550 static void free_old_xmit_skbs(struct send_queue *sq, bool in_napi)
 551 {
 552         unsigned int len;
 553         unsigned int packets = 0;
 554         unsigned int bytes = 0;
 555         void *ptr;
 556
 557         while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
 558                 if (likely(!is_xdp_frame(ptr))) {
 559                         struct sk_buff *skb = ptr;
 560
 561                         pr_debug("Sent skb %p\n", skb);
 562
 563                         bytes += skb->len;
 564                         napi_consume_skb(skb, in_napi);
 565                 } else {
 566                         struct xdp_frame *frame = ptr_to_xdp(ptr);
 567
 568                         bytes += xdp_get_frame_len(frame);
 569                         xdp_return_frame(frame);
 570                 }
 571                 packets++;
 572         }
 573
 574         /* Avoid overhead when no packets have been processed
 575          * happens when called speculatively from start_xmit.
 576          */
 577         if (!packets)
 578                 return;
 579
 580         u64_stats_update_begin(&sq->stats.syncp);
 581         sq->stats.bytes += bytes;
 582         sq->stats.packets += packets;
 583         u64_stats_update_end(&sq->stats.syncp);
 584 }
 585
 586 static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
 587 {
 588         if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
 589                 return false;
 590         else if (q < vi->curr_queue_pairs)
 591                 return true;
 592         else
 593                 return false;
 594 }
 595
 596 static void check_sq_full_and_disable(struct virtnet_info *vi,
 597                                       struct net_device *dev,
 598                                       struct send_queue *sq)
 599 {
 600         bool use_napi = sq->napi.weight;
 601         int qnum;
 602
 603         qnum = sq - vi->sq;
 604
 605         /* If running out of space, stop queue to avoid getting packets that we
 606          * are then unable to transmit.
 607          * An alternative would be to force queuing layer to requeue the skb by
 608          * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
 609          * returned in a normal path of operation: it means that driver is not
 610          * maintaining the TX queue stop/start state properly, and causes
 611          * the stack to do a non-trivial amount of useless work.
 612          * Since most packets only take 1 or 2 ring slots, stopping the queue
 613          * early means 16 slots are typically wasted.
 614          */
 615         if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
 616                 netif_stop_subqueue(dev, qnum);
 617                 if (use_napi) {
 618                         if (unlikely(!virtqueue_enable_cb_delayed(sq->vq)))
 619                                 virtqueue_napi_schedule(&sq->napi, sq->vq);
 620                 } else if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
 621                         /* More just got used, free them then recheck. */
 622                         free_old_xmit_skbs(sq, false);
 623                         if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
 624                                 netif_start_subqueue(dev, qnum);
 625                                 virtqueue_disable_cb(sq->vq);
 626                         }
 627                 }
 628         }
 629 }
 630
 631 static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
 632                                    struct send_queue *sq,
 633                                    struct xdp_frame *xdpf)
 634 {
 635         struct virtio_net_hdr_mrg_rxbuf *hdr;
 636         struct skb_shared_info *shinfo;
 637         u8 nr_frags = 0;
 638         int err, i;
 639
 640         if (unlikely(xdpf->headroom < vi->hdr_len))
 641                 return -EOVERFLOW;
 642
 643         if (unlikely(xdp_frame_has_frags(xdpf))) {
 644                 shinfo = xdp_get_shared_info_from_frame(xdpf);
 645                 nr_frags = shinfo->nr_frags;
 646         }
 647
 648         /* In wrapping function virtnet_xdp_xmit(), we need to free
 649          * up the pending old buffers, where we need to calculate the
 650          * position of skb_shared_info in xdp_get_frame_len() and
 651          * xdp_return_frame(), which will involve to xdpf->data and
 652          * xdpf->headroom. Therefore, we need to update the value of
 653          * headroom synchronously here.
 654          */
 655         xdpf->headroom -= vi->hdr_len;
 656         xdpf->data -= vi->hdr_len;
 657         /* Zero header and leave csum up to XDP layers */
 658         hdr = xdpf->data;
 659         memset(hdr, 0, vi->hdr_len);
 660         xdpf->len   += vi->hdr_len;
 661
 662         sg_init_table(sq->sg, nr_frags + 1);
 663         sg_set_buf(sq->sg, xdpf->data, xdpf->len);
 664         for (i = 0; i < nr_frags; i++) {
 665                 skb_frag_t *frag = &shinfo->frags[i];
 666
 667                 sg_set_page(&sq->sg[i + 1], skb_frag_page(frag),
 668                             skb_frag_size(frag), skb_frag_off(frag));
 669         }
 670
 671         err = virtqueue_add_outbuf(sq->vq, sq->sg, nr_frags + 1,
 672                                    xdp_to_ptr(xdpf), GFP_ATOMIC);
 673         if (unlikely(err))
 674                 return -ENOSPC; /* Caller handle free/refcnt */
 675
 676         return 0;
 677 }
 678
 679 /* when vi->curr_queue_pairs > nr_cpu_ids, the txq/sq is only used for xdp tx on
 680  * the current cpu, so it does not need to be locked.
 681  *
 682  * Here we use marco instead of inline functions because we have to deal with
 683  * three issues at the same time: 1. the choice of sq. 2. judge and execute the
 684  * lock/unlock of txq 3. make sparse happy. It is difficult for two inline
 685  * functions to perfectly solve these three problems at the same time.
 686  */
 687 #define virtnet_xdp_get_sq(vi) ({                                       \
 688         int cpu = smp_processor_id();                                   \
 689         struct netdev_queue *txq;                                       \
 690         typeof(vi) v = (vi);                                            \
 691         unsigned int qp;                                                \
 692                                                                         \
 693         if (v->curr_queue_pairs > nr_cpu_ids) {                         \
 694                 qp = v->curr_queue_pairs - v->xdp_queue_pairs;          \
 695                 qp += cpu;                                              \
 696                 txq = netdev_get_tx_queue(v->dev, qp);                  \
 697                 __netif_tx_acquire(txq);                                \
 698         } else {                                                        \
 699                 qp = cpu % v->curr_queue_pairs;                         \
 700                 txq = netdev_get_tx_queue(v->dev, qp);                  \
 701                 __netif_tx_lock(txq, cpu);                              \
 702         }                                                               \
 703         v->sq + qp;                                                     \
 704 })
 705
 706 #define virtnet_xdp_put_sq(vi, q) {                                     \
 707         struct netdev_queue *txq;                                       \
 708         typeof(vi) v = (vi);                                            \
 709                                                                         \
 710         txq = netdev_get_tx_queue(v->dev, (q) - v->sq);                 \
 711         if (v->curr_queue_pairs > nr_cpu_ids)                           \
 712                 __netif_tx_release(txq);                                \
 713         else                                                            \
 714                 __netif_tx_unlock(txq);                                 \
 715 }
 716
 717 static int virtnet_xdp_xmit(struct net_device *dev,
 718                             int n, struct xdp_frame **frames, u32 flags)
 719 {
 720         struct virtnet_info *vi = netdev_priv(dev);
 721         struct receive_queue *rq = vi->rq;
 722         struct bpf_prog *xdp_prog;
 723         struct send_queue *sq;
 724         unsigned int len;
 725         int packets = 0;
 726         int bytes = 0;
 727         int nxmit = 0;
 728         int kicks = 0;
 729         void *ptr;
 730         int ret;
 731         int i;
 732
 733         /* Only allow ndo_xdp_xmit if XDP is loaded on dev, as this
 734          * indicate XDP resources have been successfully allocated.
 735          */
 736         xdp_prog = rcu_access_pointer(rq->xdp_prog);
 737         if (!xdp_prog)
 738                 return -ENXIO;
 739
 740         sq = virtnet_xdp_get_sq(vi);
 741
 742         if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) {
 743                 ret = -EINVAL;
 744                 goto out;
 745         }
 746
 747         /* Free up any pending old buffers before queueing new ones. */
 748         while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
 749                 if (likely(is_xdp_frame(ptr))) {
 750                         struct xdp_frame *frame = ptr_to_xdp(ptr);
 751
 752                         bytes += xdp_get_frame_len(frame);
 753                         xdp_return_frame(frame);
 754                 } else {
 755                         struct sk_buff *skb = ptr;
 756
 757                         bytes += skb->len;
 758                         napi_consume_skb(skb, false);
 759                 }
 760                 packets++;
 761         }
 762
 763         for (i = 0; i < n; i++) {
 764                 struct xdp_frame *xdpf = frames[i];
 765
 766                 if (__virtnet_xdp_xmit_one(vi, sq, xdpf))
 767                         break;
 768                 nxmit++;
 769         }
 770         ret = nxmit;
 771
 772         if (!is_xdp_raw_buffer_queue(vi, sq - vi->sq))
 773                 check_sq_full_and_disable(vi, dev, sq);
 774
 775         if (flags & XDP_XMIT_FLUSH) {
 776                 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
 777                         kicks = 1;
 778         }
 779 out:
 780         u64_stats_update_begin(&sq->stats.syncp);
 781         sq->stats.bytes += bytes;
 782         sq->stats.packets += packets;
 783         sq->stats.xdp_tx += n;
 784         sq->stats.xdp_tx_drops += n - nxmit;
 785         sq->stats.kicks += kicks;
 786         u64_stats_update_end(&sq->stats.syncp);
 787
 788         virtnet_xdp_put_sq(vi, sq);
 789         return ret;
 790 }
 791
 792 static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
 793 {
 794         return vi->xdp_enabled ? VIRTIO_XDP_HEADROOM : 0;
 795 }
 796
 797 /* We copy the packet for XDP in the following cases:
 798  *
 799  * 1) Packet is scattered across multiple rx buffers.
 800  * 2) Headroom space is insufficient.
 801  *
 802  * This is inefficient but it's a temporary condition that
 803  * we hit right after XDP is enabled and until queue is refilled
 804  * with large buffers with sufficient headroom - so it should affect
 805  * at most queue size packets.
 806  * Afterwards, the conditions to enable
 807  * XDP should preclude the underlying device from sending packets
 808  * across multiple buffers (num_buf > 1), and we make sure buffers
 809  * have enough headroom.
 810  */
 811 static struct page *xdp_linearize_page(struct receive_queue *rq,
 812                                        int *num_buf,
 813                                        struct page *p,
 814                                        int offset,
 815                                        int page_off,
 816                                        unsigned int *len)
 817 {
 818         int tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 819         struct page *page;
 820
 821         if (page_off + *len + tailroom > PAGE_SIZE)
 822                 return NULL;
 823
 824         page = alloc_page(GFP_ATOMIC);
 825         if (!page)
 826                 return NULL;
 827
 828         memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
 829         page_off += *len;
 830
 831         while (--*num_buf) {
 832                 unsigned int buflen;
 833                 void *buf;
 834                 int off;
 835
 836                 buf = virtqueue_get_buf(rq->vq, &buflen);
 837                 if (unlikely(!buf))
 838                         goto err_buf;
 839
 840                 p = virt_to_head_page(buf);
 841                 off = buf - page_address(p);
 842
 843                 /* guard against a misconfigured or uncooperative backend that
 844                  * is sending packet larger than the MTU.
 845                  */
 846                 if ((page_off + buflen + tailroom) > PAGE_SIZE) {
 847                         put_page(p);
 848                         goto err_buf;
 849                 }
 850
 851                 memcpy(page_address(page) + page_off,
 852                        page_address(p) + off, buflen);
 853                 page_off += buflen;
 854                 put_page(p);
 855         }
 856
 857         /* Headroom does not contribute to packet length */
 858         *len = page_off - VIRTIO_XDP_HEADROOM;
 859         return page;
 860 err_buf:
 861         __free_pages(page, 0);
 862         return NULL;
 863 }
 864
 865 static struct sk_buff *receive_small(struct net_device *dev,
 866                                      struct virtnet_info *vi,
 867                                      struct receive_queue *rq,
 868                                      void *buf, void *ctx,
 869                                      unsigned int len,
 870                                      unsigned int *xdp_xmit,
 871                                      struct virtnet_rq_stats *stats)
 872 {
 873         struct sk_buff *skb;
 874         struct bpf_prog *xdp_prog;
 875         unsigned int xdp_headroom = (unsigned long)ctx;
 876         unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
 877         unsigned int headroom = vi->hdr_len + header_offset;
 878         unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
 879                               SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 880         struct page *page = virt_to_head_page(buf);
 881         unsigned int delta = 0;
 882         struct page *xdp_page;
 883         int err;
 884         unsigned int metasize = 0;
 885
 886         len -= vi->hdr_len;
 887         stats->bytes += len;
 888
 889         if (unlikely(len > GOOD_PACKET_LEN)) {
 890                 pr_debug("%s: rx error: len %u exceeds max size %d\n",
 891                          dev->name, len, GOOD_PACKET_LEN);
 892                 dev->stats.rx_length_errors++;
 893                 goto err;
 894         }
 895
 896         if (likely(!vi->xdp_enabled)) {
 897                 xdp_prog = NULL;
 898                 goto skip_xdp;
 899         }
 900
 901         rcu_read_lock();
 902         xdp_prog = rcu_dereference(rq->xdp_prog);
 903         if (xdp_prog) {
 904                 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
 905                 struct xdp_frame *xdpf;
 906                 struct xdp_buff xdp;
 907                 void *orig_data;
 908                 u32 act;
 909
 910                 if (unlikely(hdr->hdr.gso_type))
 911                         goto err_xdp;
 912
 913                 if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
 914                         int offset = buf - page_address(page) + header_offset;
 915                         unsigned int tlen = len + vi->hdr_len;
 916                         int num_buf = 1;
 917
 918                         xdp_headroom = virtnet_get_headroom(vi);
 919                         header_offset = VIRTNET_RX_PAD + xdp_headroom;
 920                         headroom = vi->hdr_len + header_offset;
 921                         buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
 922                                  SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 923                         xdp_page = xdp_linearize_page(rq, &num_buf, page,
 924                                                       offset, header_offset,
 925                                                       &tlen);
 926                         if (!xdp_page)
 927                                 goto err_xdp;
 928
 929                         buf = page_address(xdp_page);
 930                         put_page(page);
 931                         page = xdp_page;
 932                 }
 933
 934                 xdp_init_buff(&xdp, buflen, &rq->xdp_rxq);
 935                 xdp_prepare_buff(&xdp, buf + VIRTNET_RX_PAD + vi->hdr_len,
 936                                  xdp_headroom, len, true);
 937                 orig_data = xdp.data;
 938                 act = bpf_prog_run_xdp(xdp_prog, &xdp);
 939                 stats->xdp_packets++;
 940
 941                 switch (act) {
 942                 case XDP_PASS:
 943                         /* Recalculate length in case bpf program changed it */
 944                         delta = orig_data - xdp.data;
 945                         len = xdp.data_end - xdp.data;
 946                         metasize = xdp.data - xdp.data_meta;
 947                         break;
 948                 case XDP_TX:
 949                         stats->xdp_tx++;
 950                         xdpf = xdp_convert_buff_to_frame(&xdp);
 951                         if (unlikely(!xdpf))
 952                                 goto err_xdp;
 953                         err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
 954                         if (unlikely(!err)) {
 955                                 xdp_return_frame_rx_napi(xdpf);
 956                         } else if (unlikely(err < 0)) {
 957                                 trace_xdp_exception(vi->dev, xdp_prog, act);
 958                                 goto err_xdp;
 959                         }
 960                         *xdp_xmit |= VIRTIO_XDP_TX;
 961                         rcu_read_unlock();
 962                         goto xdp_xmit;
 963                 case XDP_REDIRECT:
 964                         stats->xdp_redirects++;
 965                         err = xdp_do_redirect(dev, &xdp, xdp_prog);
 966                         if (err)
 967                                 goto err_xdp;
 968                         *xdp_xmit |= VIRTIO_XDP_REDIR;
 969                         rcu_read_unlock();
 970                         goto xdp_xmit;
 971                 default:
 972                         bpf_warn_invalid_xdp_action(vi->dev, xdp_prog, act);
 973                         fallthrough;
 974                 case XDP_ABORTED:
 975                         trace_xdp_exception(vi->dev, xdp_prog, act);
 976                         goto err_xdp;
 977                 case XDP_DROP:
 978                         goto err_xdp;
 979                 }
 980         }
 981         rcu_read_unlock();
 982
 983 skip_xdp:
 984         skb = build_skb(buf, buflen);
 985         if (!skb)
 986                 goto err;
 987         skb_reserve(skb, headroom - delta);
 988         skb_put(skb, len);
 989         if (!xdp_prog) {
 990                 buf += header_offset;
 991                 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
 992         } /* keep zeroed vnet hdr since XDP is loaded */
 993
 994         if (metasize)
 995                 skb_metadata_set(skb, metasize);
 996
 997         return skb;
 998
 999 err_xdp:
1000         rcu_read_unlock();
1001         stats->xdp_drops++;
1002 err:
1003         stats->drops++;
1004         put_page(page);
1005 xdp_xmit:
1006         return NULL;
1007 }
1008
1009 static struct sk_buff *receive_big(struct net_device *dev,
1010                                    struct virtnet_info *vi,
1011                                    struct receive_queue *rq,
1012                                    void *buf,
1013                                    unsigned int len,
1014                                    struct virtnet_rq_stats *stats)
1015 {
1016         struct page *page = buf;
1017         struct sk_buff *skb =
1018                 page_to_skb(vi, rq, page, 0, len, PAGE_SIZE, 0);
1019
1020         stats->bytes += len - vi->hdr_len;
1021         if (unlikely(!skb))
1022                 goto err;
1023
1024         return skb;
1025
1026 err:
1027         stats->drops++;
1028         give_pages(rq, page);
1029         return NULL;
1030 }
1031
1032 /* Why not use xdp_build_skb_from_frame() ?
1033  * XDP core assumes that xdp frags are PAGE_SIZE in length, while in
1034  * virtio-net there are 2 points that do not match its requirements:
1035  *  1. The size of the prefilled buffer is not fixed before xdp is set.
1036  *  2. xdp_build_skb_from_frame() does more checks that we don't need,
1037  *     like eth_type_trans() (which virtio-net does in receive_buf()).
1038  */
1039 static struct sk_buff *build_skb_from_xdp_buff(struct net_device *dev,
1040                                                struct virtnet_info *vi,
1041                                                struct xdp_buff *xdp,
1042                                                unsigned int xdp_frags_truesz)
1043 {
1044         struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
1045         unsigned int headroom, data_len;
1046         struct sk_buff *skb;
1047         int metasize;
1048         u8 nr_frags;
1049
1050         if (unlikely(xdp->data_end > xdp_data_hard_end(xdp))) {
1051                 pr_debug("Error building skb as missing reserved tailroom for xdp");
1052                 return NULL;
1053         }
1054
1055         if (unlikely(xdp_buff_has_frags(xdp)))
1056                 nr_frags = sinfo->nr_frags;
1057
1058         skb = build_skb(xdp->data_hard_start, xdp->frame_sz);
1059         if (unlikely(!skb))
1060                 return NULL;
1061
1062         headroom = xdp->data - xdp->data_hard_start;
1063         data_len = xdp->data_end - xdp->data;
1064         skb_reserve(skb, headroom);
1065         __skb_put(skb, data_len);
1066
1067         metasize = xdp->data - xdp->data_meta;
1068         metasize = metasize > 0 ? metasize : 0;
1069         if (metasize)
1070                 skb_metadata_set(skb, metasize);
1071
1072         if (unlikely(xdp_buff_has_frags(xdp)))
1073                 xdp_update_skb_shared_info(skb, nr_frags,
1074                                            sinfo->xdp_frags_size,
1075                                            xdp_frags_truesz,
1076                                            xdp_buff_is_frag_pfmemalloc(xdp));
1077
1078         return skb;
1079 }
1080
1081 /* TODO: build xdp in big mode */
1082 static int virtnet_build_xdp_buff_mrg(struct net_device *dev,
1083                                       struct virtnet_info *vi,
1084                                       struct receive_queue *rq,
1085                                       struct xdp_buff *xdp,
1086                                       void *buf,
1087                                       unsigned int len,
1088                                       unsigned int frame_sz,
1089                                       int *num_buf,
1090                                       unsigned int *xdp_frags_truesize,
1091                                       struct virtnet_rq_stats *stats)
1092 {
1093         struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
1094         unsigned int headroom, tailroom, room;
1095         unsigned int truesize, cur_frag_size;
1096         struct skb_shared_info *shinfo;
1097         unsigned int xdp_frags_truesz = 0;
1098         struct page *page;
1099         skb_frag_t *frag;
1100         int offset;
1101         void *ctx;
1102
1103         xdp_init_buff(xdp, frame_sz, &rq->xdp_rxq);
1104         xdp_prepare_buff(xdp, buf - VIRTIO_XDP_HEADROOM,
1105                          VIRTIO_XDP_HEADROOM + vi->hdr_len, len - vi->hdr_len, true);
1106
1107         if (!*num_buf)
1108                 return 0;
1109
1110         if (*num_buf > 1) {
1111                 /* If we want to build multi-buffer xdp, we need
1112                  * to specify that the flags of xdp_buff have the
1113                  * XDP_FLAGS_HAS_FRAG bit.
1114                  */
1115                 if (!xdp_buff_has_frags(xdp))
1116                         xdp_buff_set_frags_flag(xdp);
1117
1118                 shinfo = xdp_get_shared_info_from_buff(xdp);
1119                 shinfo->nr_frags = 0;
1120                 shinfo->xdp_frags_size = 0;
1121         }
1122
1123         if (*num_buf > MAX_SKB_FRAGS + 1)
1124                 return -EINVAL;
1125
1126         while (--*num_buf > 0) {
1127                 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
1128                 if (unlikely(!buf)) {
1129                         pr_debug("%s: rx error: %d buffers out of %d missing\n",
1130                                  dev->name, *num_buf,
1131                                  virtio16_to_cpu(vi->vdev, hdr->num_buffers));
1132                         dev->stats.rx_length_errors++;
1133                         return -EINVAL;
1134                 }
1135
1136                 stats->bytes += len;
1137                 page = virt_to_head_page(buf);
1138                 offset = buf - page_address(page);
1139
1140                 truesize = mergeable_ctx_to_truesize(ctx);
1141                 headroom = mergeable_ctx_to_headroom(ctx);
1142                 tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
1143                 room = SKB_DATA_ALIGN(headroom + tailroom);
1144
1145                 cur_frag_size = truesize;
1146                 xdp_frags_truesz += cur_frag_size;
1147                 if (unlikely(len > truesize - room || cur_frag_size > PAGE_SIZE)) {
1148                         put_page(page);
1149                         pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
1150                                  dev->name, len, (unsigned long)(truesize - room));
1151                         dev->stats.rx_length_errors++;
1152                         return -EINVAL;
1153                 }
1154
1155                 frag = &shinfo->frags[shinfo->nr_frags++];
1156                 __skb_frag_set_page(frag, page);
1157                 skb_frag_off_set(frag, offset);
1158                 skb_frag_size_set(frag, len);
1159                 if (page_is_pfmemalloc(page))
1160                         xdp_buff_set_frag_pfmemalloc(xdp);
1161
1162                 shinfo->xdp_frags_size += len;
1163         }
1164
1165         *xdp_frags_truesize = xdp_frags_truesz;
1166         return 0;
1167 }
1168
1169 static struct sk_buff *receive_mergeable(struct net_device *dev,
1170                                          struct virtnet_info *vi,
1171                                          struct receive_queue *rq,
1172                                          void *buf,
1173                                          void *ctx,
1174                                          unsigned int len,
1175                                          unsigned int *xdp_xmit,
1176                                          struct virtnet_rq_stats *stats)
1177 {
1178         struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
1179         int num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
1180         struct page *page = virt_to_head_page(buf);
1181         int offset = buf - page_address(page);
1182         struct sk_buff *head_skb, *curr_skb;
1183         struct bpf_prog *xdp_prog;
1184         unsigned int truesize = mergeable_ctx_to_truesize(ctx);
1185         unsigned int headroom = mergeable_ctx_to_headroom(ctx);
1186         unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
1187         unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
1188         unsigned int frame_sz, xdp_room;
1189         int err;
1190
1191         head_skb = NULL;
1192         stats->bytes += len - vi->hdr_len;
1193
1194         if (unlikely(len > truesize - room)) {
1195                 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
1196                          dev->name, len, (unsigned long)(truesize - room));
1197                 dev->stats.rx_length_errors++;
1198                 goto err_skb;
1199         }
1200
1201         if (likely(!vi->xdp_enabled)) {
1202                 xdp_prog = NULL;
1203                 goto skip_xdp;
1204         }
1205
1206         rcu_read_lock();
1207         xdp_prog = rcu_dereference(rq->xdp_prog);
1208         if (xdp_prog) {
1209                 unsigned int xdp_frags_truesz = 0;
1210                 struct skb_shared_info *shinfo;
1211                 struct xdp_frame *xdpf;
1212                 struct page *xdp_page;
1213                 struct xdp_buff xdp;
1214                 void *data;
1215                 u32 act;
1216                 int i;
1217
1218                 /* Transient failure which in theory could occur if
1219                  * in-flight packets from before XDP was enabled reach
1220                  * the receive path after XDP is loaded.
1221                  */
1222                 if (unlikely(hdr->hdr.gso_type))
1223                         goto err_xdp;
1224
1225                 /* Now XDP core assumes frag size is PAGE_SIZE, but buffers
1226                  * with headroom may add hole in truesize, which
1227                  * make their length exceed PAGE_SIZE. So we disabled the
1228                  * hole mechanism for xdp. See add_recvbuf_mergeable().
1229                  */
1230                 frame_sz = truesize;
1231
1232                 /* This happens when headroom is not enough because
1233                  * of the buffer was prefilled before XDP is set.
1234                  * This should only happen for the first several packets.
1235                  * In fact, vq reset can be used here to help us clean up
1236                  * the prefilled buffers, but many existing devices do not
1237                  * support it, and we don't want to bother users who are
1238                  * using xdp normally.
1239                  */
1240                 if (!xdp_prog->aux->xdp_has_frags &&
1241                     (num_buf > 1 || headroom < virtnet_get_headroom(vi))) {
1242                         /* linearize data for XDP */
1243                         xdp_page = xdp_linearize_page(rq, &num_buf,
1244                                                       page, offset,
1245                                                       VIRTIO_XDP_HEADROOM,
1246                                                       &len);
1247                         frame_sz = PAGE_SIZE;
1248
1249                         if (!xdp_page)
1250                                 goto err_xdp;
1251                         offset = VIRTIO_XDP_HEADROOM;
1252                 } else if (unlikely(headroom < virtnet_get_headroom(vi))) {
1253                         xdp_room = SKB_DATA_ALIGN(VIRTIO_XDP_HEADROOM +
1254                                                   sizeof(struct skb_shared_info));
1255                         if (len + xdp_room > PAGE_SIZE)
1256                                 goto err_xdp;
1257
1258                         xdp_page = alloc_page(GFP_ATOMIC);
1259                         if (!xdp_page)
1260                                 goto err_xdp;
1261
1262                         memcpy(page_address(xdp_page) + VIRTIO_XDP_HEADROOM,
1263                                page_address(page) + offset, len);
1264                         frame_sz = PAGE_SIZE;
1265                         offset = VIRTIO_XDP_HEADROOM;
1266                 } else {
1267                         xdp_page = page;
1268                 }
1269
1270                 data = page_address(xdp_page) + offset;
1271                 err = virtnet_build_xdp_buff_mrg(dev, vi, rq, &xdp, data, len, frame_sz,
1272                                                  &num_buf, &xdp_frags_truesz, stats);
1273                 if (unlikely(err))
1274                         goto err_xdp_frags;
1275
1276                 act = bpf_prog_run_xdp(xdp_prog, &xdp);
1277                 stats->xdp_packets++;
1278
1279                 switch (act) {
1280                 case XDP_PASS:
1281                         head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz);
1282                         if (unlikely(!head_skb))
1283                                 goto err_xdp_frags;
1284
1285                         if (unlikely(xdp_page != page))
1286                                 put_page(page);
1287                         rcu_read_unlock();
1288                         return head_skb;
1289                 case XDP_TX:
1290                         stats->xdp_tx++;
1291                         xdpf = xdp_convert_buff_to_frame(&xdp);
1292                         if (unlikely(!xdpf)) {
1293                                 netdev_dbg(dev, "convert buff to frame failed for xdp\n");
1294                                 goto err_xdp_frags;
1295                         }
1296                         err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
1297                         if (unlikely(!err)) {
1298                                 xdp_return_frame_rx_napi(xdpf);
1299                         } else if (unlikely(err < 0)) {
1300                                 trace_xdp_exception(vi->dev, xdp_prog, act);
1301                                 goto err_xdp_frags;
1302                         }
1303                         *xdp_xmit |= VIRTIO_XDP_TX;
1304                         if (unlikely(xdp_page != page))
1305                                 put_page(page);
1306                         rcu_read_unlock();
1307                         goto xdp_xmit;
1308                 case XDP_REDIRECT:
1309                         stats->xdp_redirects++;
1310                         err = xdp_do_redirect(dev, &xdp, xdp_prog);
1311                         if (err)
1312                                 goto err_xdp_frags;
1313                         *xdp_xmit |= VIRTIO_XDP_REDIR;
1314                         if (unlikely(xdp_page != page))
1315                                 put_page(page);
1316                         rcu_read_unlock();
1317                         goto xdp_xmit;
1318                 default:
1319                         bpf_warn_invalid_xdp_action(vi->dev, xdp_prog, act);
1320                         fallthrough;
1321                 case XDP_ABORTED:
1322                         trace_xdp_exception(vi->dev, xdp_prog, act);
1323                         fallthrough;
1324                 case XDP_DROP:
1325                         goto err_xdp_frags;
1326                 }
1327 err_xdp_frags:
1328                 if (unlikely(xdp_page != page))
1329                         __free_pages(xdp_page, 0);
1330
1331                 if (xdp_buff_has_frags(&xdp)) {
1332                         shinfo = xdp_get_shared_info_from_buff(&xdp);
1333                         for (i = 0; i < shinfo->nr_frags; i++) {
1334                                 xdp_page = skb_frag_page(&shinfo->frags[i]);
1335                                 put_page(xdp_page);
1336                         }
1337                 }
1338
1339                 goto err_xdp;
1340         }
1341         rcu_read_unlock();
1342
1343 skip_xdp:
1344         head_skb = page_to_skb(vi, rq, page, offset, len, truesize, headroom);
1345         curr_skb = head_skb;
1346
1347         if (unlikely(!curr_skb))
1348                 goto err_skb;
1349         while (--num_buf) {
1350                 int num_skb_frags;
1351
1352                 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
1353                 if (unlikely(!buf)) {
1354                         pr_debug("%s: rx error: %d buffers out of %d missing\n",
1355                                  dev->name, num_buf,
1356                                  virtio16_to_cpu(vi->vdev,
1357                                                  hdr->num_buffers));
1358                         dev->stats.rx_length_errors++;
1359                         goto err_buf;
1360                 }
1361
1362                 stats->bytes += len;
1363                 page = virt_to_head_page(buf);
1364
1365                 truesize = mergeable_ctx_to_truesize(ctx);
1366                 headroom = mergeable_ctx_to_headroom(ctx);
1367                 tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
1368                 room = SKB_DATA_ALIGN(headroom + tailroom);
1369                 if (unlikely(len > truesize - room)) {
1370                         pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
1371                                  dev->name, len, (unsigned long)(truesize - room));
1372                         dev->stats.rx_length_errors++;
1373                         goto err_skb;
1374                 }
1375
1376                 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
1377                 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
1378                         struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
1379
1380                         if (unlikely(!nskb))
1381                                 goto err_skb;
1382                         if (curr_skb == head_skb)
1383                                 skb_shinfo(curr_skb)->frag_list = nskb;
1384                         else
1385                                 curr_skb->next = nskb;
1386                         curr_skb = nskb;
1387                         head_skb->truesize += nskb->truesize;
1388                         num_skb_frags = 0;
1389                 }
1390                 if (curr_skb != head_skb) {
1391                         head_skb->data_len += len;
1392                         head_skb->len += len;
1393                         head_skb->truesize += truesize;
1394                 }
1395                 offset = buf - page_address(page);
1396                 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
1397                         put_page(page);
1398                         skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
1399                                              len, truesize);
1400                 } else {
1401                         skb_add_rx_frag(curr_skb, num_skb_frags, page,
1402                                         offset, len, truesize);
1403                 }
1404         }
1405
1406         ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
1407         return head_skb;
1408
1409 err_xdp:
1410         rcu_read_unlock();
1411         stats->xdp_drops++;
1412 err_skb:
1413         put_page(page);
1414         while (num_buf-- > 1) {
1415                 buf = virtqueue_get_buf(rq->vq, &len);
1416                 if (unlikely(!buf)) {
1417                         pr_debug("%s: rx error: %d buffers missing\n",
1418                                  dev->name, num_buf);
1419                         dev->stats.rx_length_errors++;
1420                         break;
1421                 }
1422                 stats->bytes += len;
1423                 page = virt_to_head_page(buf);
1424                 put_page(page);
1425         }
1426 err_buf:
1427         stats->drops++;
1428         dev_kfree_skb(head_skb);
1429 xdp_xmit:
1430         return NULL;
1431 }
1432
1433 static void virtio_skb_set_hash(const struct virtio_net_hdr_v1_hash *hdr_hash,
1434                                 struct sk_buff *skb)
1435 {
1436         enum pkt_hash_types rss_hash_type;
1437
1438         if (!hdr_hash || !skb)
1439                 return;
1440
1441         switch (__le16_to_cpu(hdr_hash->hash_report)) {
1442         case VIRTIO_NET_HASH_REPORT_TCPv4:
1443         case VIRTIO_NET_HASH_REPORT_UDPv4:
1444         case VIRTIO_NET_HASH_REPORT_TCPv6:
1445         case VIRTIO_NET_HASH_REPORT_UDPv6:
1446         case VIRTIO_NET_HASH_REPORT_TCPv6_EX:
1447         case VIRTIO_NET_HASH_REPORT_UDPv6_EX:
1448                 rss_hash_type = PKT_HASH_TYPE_L4;
1449                 break;
1450         case VIRTIO_NET_HASH_REPORT_IPv4:
1451         case VIRTIO_NET_HASH_REPORT_IPv6:
1452         case VIRTIO_NET_HASH_REPORT_IPv6_EX:
1453                 rss_hash_type = PKT_HASH_TYPE_L3;
1454                 break;
1455         case VIRTIO_NET_HASH_REPORT_NONE:
1456         default:
1457                 rss_hash_type = PKT_HASH_TYPE_NONE;
1458         }
1459         skb_set_hash(skb, __le32_to_cpu(hdr_hash->hash_value), rss_hash_type);
1460 }
1461
1462 static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
1463                         void *buf, unsigned int len, void **ctx,
1464                         unsigned int *xdp_xmit,
1465                         struct virtnet_rq_stats *stats)
1466 {
1467         struct net_device *dev = vi->dev;
1468         struct sk_buff *skb;
1469         struct virtio_net_hdr_mrg_rxbuf *hdr;
1470
1471         if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
1472                 pr_debug("%s: short packet %i\n", dev->name, len);
1473                 dev->stats.rx_length_errors++;
1474                 virtnet_rq_free_unused_buf(rq->vq, buf);
1475                 return;
1476         }
1477
1478         if (vi->mergeable_rx_bufs)
1479                 skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit,
1480                                         stats);
1481         else if (vi->big_packets)
1482                 skb = receive_big(dev, vi, rq, buf, len, stats);
1483         else
1484                 skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats);
1485
1486         if (unlikely(!skb))
1487                 return;
1488
1489         hdr = skb_vnet_hdr(skb);
1490         if (dev->features & NETIF_F_RXHASH && vi->has_rss_hash_report)
1491                 virtio_skb_set_hash((const struct virtio_net_hdr_v1_hash *)hdr, skb);
1492
1493         if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
1494                 skb->ip_summed = CHECKSUM_UNNECESSARY;
1495
1496         if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
1497                                   virtio_is_little_endian(vi->vdev))) {
1498                 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
1499                                      dev->name, hdr->hdr.gso_type,
1500                                      hdr->hdr.gso_size);
1501                 goto frame_err;
1502         }
1503
1504         skb_record_rx_queue(skb, vq2rxq(rq->vq));
1505         skb->protocol = eth_type_trans(skb, dev);
1506         pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
1507                  ntohs(skb->protocol), skb->len, skb->pkt_type);
1508
1509         napi_gro_receive(&rq->napi, skb);
1510         return;
1511
1512 frame_err:
1513         dev->stats.rx_frame_errors++;
1514         dev_kfree_skb(skb);
1515 }
1516
1517 /* Unlike mergeable buffers, all buffers are allocated to the
1518  * same size, except for the headroom. For this reason we do
1519  * not need to use  mergeable_len_to_ctx here - it is enough
1520  * to store the headroom as the context ignoring the truesize.
1521  */
1522 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
1523                              gfp_t gfp)
1524 {
1525         struct page_frag *alloc_frag = &rq->alloc_frag;
1526         char *buf;
1527         unsigned int xdp_headroom = virtnet_get_headroom(vi);
1528         void *ctx = (void *)(unsigned long)xdp_headroom;
1529         int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
1530         int err;
1531
1532         len = SKB_DATA_ALIGN(len) +
1533               SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
1534         if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
1535                 return -ENOMEM;
1536
1537         buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1538         get_page(alloc_frag->page);
1539         alloc_frag->offset += len;
1540         sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
1541                     vi->hdr_len + GOOD_PACKET_LEN);
1542         err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1543         if (err < 0)
1544                 put_page(virt_to_head_page(buf));
1545         return err;
1546 }
1547
1548 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
1549                            gfp_t gfp)
1550 {
1551         struct page *first, *list = NULL;
1552         char *p;
1553         int i, err, offset;
1554
1555         sg_init_table(rq->sg, vi->big_packets_num_skbfrags + 2);
1556
1557         /* page in rq->sg[vi->big_packets_num_skbfrags + 1] is list tail */
1558         for (i = vi->big_packets_num_skbfrags + 1; i > 1; --i) {
1559                 first = get_a_page(rq, gfp);
1560                 if (!first) {
1561                         if (list)
1562                                 give_pages(rq, list);
1563                         return -ENOMEM;
1564                 }
1565                 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
1566
1567                 /* chain new page in list head to match sg */
1568                 first->private = (unsigned long)list;
1569                 list = first;
1570         }
1571
1572         first = get_a_page(rq, gfp);
1573         if (!first) {
1574                 give_pages(rq, list);
1575                 return -ENOMEM;
1576         }
1577         p = page_address(first);
1578
1579         /* rq->sg[0], rq->sg[1] share the same page */
1580         /* a separated rq->sg[0] for header - required in case !any_header_sg */
1581         sg_set_buf(&rq->sg[0], p, vi->hdr_len);
1582
1583         /* rq->sg[1] for data packet, from offset */
1584         offset = sizeof(struct padded_vnet_hdr);
1585         sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
1586
1587         /* chain first in list head */
1588         first->private = (unsigned long)list;
1589         err = virtqueue_add_inbuf(rq->vq, rq->sg, vi->big_packets_num_skbfrags + 2,
1590                                   first, gfp);
1591         if (err < 0)
1592                 give_pages(rq, first);
1593
1594         return err;
1595 }
1596
1597 static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
1598                                           struct ewma_pkt_len *avg_pkt_len,
1599                                           unsigned int room)
1600 {
1601         struct virtnet_info *vi = rq->vq->vdev->priv;
1602         const size_t hdr_len = vi->hdr_len;
1603         unsigned int len;
1604
1605         if (room)
1606                 return PAGE_SIZE - room;
1607
1608         len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
1609                                 rq->min_buf_len, PAGE_SIZE - hdr_len);
1610
1611         return ALIGN(len, L1_CACHE_BYTES);
1612 }
1613
1614 static int add_recvbuf_mergeable(struct virtnet_info *vi,
1615                                  struct receive_queue *rq, gfp_t gfp)
1616 {
1617         struct page_frag *alloc_frag = &rq->alloc_frag;
1618         unsigned int headroom = virtnet_get_headroom(vi);
1619         unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
1620         unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
1621         char *buf;
1622         void *ctx;
1623         int err;
1624         unsigned int len, hole;
1625
1626         /* Extra tailroom is needed to satisfy XDP's assumption. This
1627          * means rx frags coalescing won't work, but consider we've
1628          * disabled GSO for XDP, it won't be a big issue.
1629          */
1630         len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len, room);
1631         if (unlikely(!skb_page_frag_refill(len + room, alloc_frag, gfp)))
1632                 return -ENOMEM;
1633
1634         buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1635         buf += headroom; /* advance address leaving hole at front of pkt */
1636         get_page(alloc_frag->page);
1637         alloc_frag->offset += len + room;
1638         hole = alloc_frag->size - alloc_frag->offset;
1639         if (hole < len + room) {
1640                 /* To avoid internal fragmentation, if there is very likely not
1641                  * enough space for another buffer, add the remaining space to
1642                  * the current buffer.
1643                  * XDP core assumes that frame_size of xdp_buff and the length
1644                  * of the frag are PAGE_SIZE, so we disable the hole mechanism.
1645                  */
1646                 if (!headroom)
1647                         len += hole;
1648                 alloc_frag->offset += hole;
1649         }
1650
1651         sg_init_one(rq->sg, buf, len);
1652         ctx = mergeable_len_to_ctx(len + room, headroom);
1653         err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1654         if (err < 0)
1655                 put_page(virt_to_head_page(buf));
1656
1657         return err;
1658 }
1659
1660 /*
1661  * Returns false if we couldn't fill entirely (OOM).
1662  *
1663  * Normally run in the receive path, but can also be run from ndo_open
1664  * before we're receiving packets, or from refill_work which is
1665  * careful to disable receiving (using napi_disable).
1666  */
1667 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
1668                           gfp_t gfp)
1669 {
1670         int err;
1671         bool oom;
1672
1673         do {
1674                 if (vi->mergeable_rx_bufs)
1675                         err = add_recvbuf_mergeable(vi, rq, gfp);
1676                 else if (vi->big_packets)
1677                         err = add_recvbuf_big(vi, rq, gfp);
1678                 else
1679                         err = add_recvbuf_small(vi, rq, gfp);
1680
1681                 oom = err == -ENOMEM;
1682                 if (err)
1683                         break;
1684         } while (rq->vq->num_free);
1685         if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
1686                 unsigned long flags;
1687
1688                 flags = u64_stats_update_begin_irqsave(&rq->stats.syncp);
1689                 rq->stats.kicks++;
1690                 u64_stats_update_end_irqrestore(&rq->stats.syncp, flags);
1691         }
1692
1693         return !oom;
1694 }
1695
1696 static void skb_recv_done(struct virtqueue *rvq)
1697 {
1698         struct virtnet_info *vi = rvq->vdev->priv;
1699         struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
1700
1701         virtqueue_napi_schedule(&rq->napi, rvq);
1702 }
1703
1704 static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
1705 {
1706         napi_enable(napi);
1707
1708         /* If all buffers were filled by other side before we napi_enabled, we
1709          * won't get another interrupt, so process any outstanding packets now.
1710          * Call local_bh_enable after to trigger softIRQ processing.
1711          */
1712         local_bh_disable();
1713         virtqueue_napi_schedule(napi, vq);
1714         local_bh_enable();
1715 }
1716
1717 static void virtnet_napi_tx_enable(struct virtnet_info *vi,
1718                                    struct virtqueue *vq,
1719                                    struct napi_struct *napi)
1720 {
1721         if (!napi->weight)
1722                 return;
1723
1724         /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
1725          * enable the feature if this is likely affine with the transmit path.
1726          */
1727         if (!vi->affinity_hint_set) {
1728                 napi->weight = 0;
1729                 return;
1730         }
1731
1732         return virtnet_napi_enable(vq, napi);
1733 }
1734
1735 static void virtnet_napi_tx_disable(struct napi_struct *napi)
1736 {
1737         if (napi->weight)
1738                 napi_disable(napi);
1739 }
1740
1741 static void refill_work(struct work_struct *work)
1742 {
1743         struct virtnet_info *vi =
1744                 container_of(work, struct virtnet_info, refill.work);
1745         bool still_empty;
1746         int i;
1747
1748         for (i = 0; i < vi->curr_queue_pairs; i++) {
1749                 struct receive_queue *rq = &vi->rq[i];
1750
1751                 napi_disable(&rq->napi);
1752                 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
1753                 virtnet_napi_enable(rq->vq, &rq->napi);
1754
1755                 /* In theory, this can happen: if we don't get any buffers in
1756                  * we will *never* try to fill again.
1757                  */
1758                 if (still_empty)
1759                         schedule_delayed_work(&vi->refill, HZ/2);
1760         }
1761 }
1762
1763 static int virtnet_receive(struct receive_queue *rq, int budget,
1764                            unsigned int *xdp_xmit)
1765 {
1766         struct virtnet_info *vi = rq->vq->vdev->priv;
1767         struct virtnet_rq_stats stats = {};
1768         unsigned int len;
1769         void *buf;
1770         int i;
1771
1772         if (!vi->big_packets || vi->mergeable_rx_bufs) {
1773                 void *ctx;
1774
1775                 while (stats.packets < budget &&
1776                        (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) {
1777                         receive_buf(vi, rq, buf, len, ctx, xdp_xmit, &stats);
1778                         stats.packets++;
1779                 }
1780         } else {
1781                 while (stats.packets < budget &&
1782                        (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
1783                         receive_buf(vi, rq, buf, len, NULL, xdp_xmit, &stats);
1784                         stats.packets++;
1785                 }
1786         }
1787
1788         if (rq->vq->num_free > min((unsigned int)budget, virtqueue_get_vring_size(rq->vq)) / 2) {
1789                 if (!try_fill_recv(vi, rq, GFP_ATOMIC)) {
1790                         spin_lock(&vi->refill_lock);
1791                         if (vi->refill_enabled)
1792                                 schedule_delayed_work(&vi->refill, 0);
1793                         spin_unlock(&vi->refill_lock);
1794                 }
1795         }
1796
1797         u64_stats_update_begin(&rq->stats.syncp);
1798         for (i = 0; i < VIRTNET_RQ_STATS_LEN; i++) {
1799                 size_t offset = virtnet_rq_stats_desc[i].offset;
1800                 u64 *item;
1801
1802                 item = (u64 *)((u8 *)&rq->stats + offset);
1803                 *item += *(u64 *)((u8 *)&stats + offset);
1804         }
1805         u64_stats_update_end(&rq->stats.syncp);
1806
1807         return stats.packets;
1808 }
1809
1810 static void virtnet_poll_cleantx(struct receive_queue *rq)
1811 {
1812         struct virtnet_info *vi = rq->vq->vdev->priv;
1813         unsigned int index = vq2rxq(rq->vq);
1814         struct send_queue *sq = &vi->sq[index];
1815         struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
1816
1817         if (!sq->napi.weight || is_xdp_raw_buffer_queue(vi, index))
1818                 return;
1819
1820         if (__netif_tx_trylock(txq)) {
1821                 if (sq->reset) {
1822                         __netif_tx_unlock(txq);
1823                         return;
1824                 }
1825
1826                 do {
1827                         virtqueue_disable_cb(sq->vq);
1828                         free_old_xmit_skbs(sq, true);
1829                 } while (unlikely(!virtqueue_enable_cb_delayed(sq->vq)));
1830
1831                 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1832                         netif_tx_wake_queue(txq);
1833
1834                 __netif_tx_unlock(txq);
1835         }
1836 }
1837
1838 static int virtnet_poll(struct napi_struct *napi, int budget)
1839 {
1840         struct receive_queue *rq =
1841                 container_of(napi, struct receive_queue, napi);
1842         struct virtnet_info *vi = rq->vq->vdev->priv;
1843         struct send_queue *sq;
1844         unsigned int received;
1845         unsigned int xdp_xmit = 0;
1846
1847         virtnet_poll_cleantx(rq);
1848
1849         received = virtnet_receive(rq, budget, &xdp_xmit);
1850
1851         if (xdp_xmit & VIRTIO_XDP_REDIR)
1852                 xdp_do_flush();
1853
1854         /* Out of packets? */
1855         if (received < budget)
1856                 virtqueue_napi_complete(napi, rq->vq, received);
1857
1858         if (xdp_xmit & VIRTIO_XDP_TX) {
1859                 sq = virtnet_xdp_get_sq(vi);
1860                 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1861                         u64_stats_update_begin(&sq->stats.syncp);
1862                         sq->stats.kicks++;
1863                         u64_stats_update_end(&sq->stats.syncp);
1864                 }
1865                 virtnet_xdp_put_sq(vi, sq);
1866         }
1867
1868         return received;
1869 }
1870
1871 static void virtnet_disable_queue_pair(struct virtnet_info *vi, int qp_index)
1872 {
1873         virtnet_napi_tx_disable(&vi->sq[qp_index].napi);
1874         napi_disable(&vi->rq[qp_index].napi);
1875         xdp_rxq_info_unreg(&vi->rq[qp_index].xdp_rxq);
1876 }
1877
1878 static int virtnet_enable_queue_pair(struct virtnet_info *vi, int qp_index)
1879 {
1880         struct net_device *dev = vi->dev;
1881         int err;
1882
1883         err = xdp_rxq_info_reg(&vi->rq[qp_index].xdp_rxq, dev, qp_index,
1884                                vi->rq[qp_index].napi.napi_id);
1885         if (err < 0)
1886                 return err;
1887
1888         err = xdp_rxq_info_reg_mem_model(&vi->rq[qp_index].xdp_rxq,
1889                                          MEM_TYPE_PAGE_SHARED, NULL);
1890         if (err < 0)
1891                 goto err_xdp_reg_mem_model;
1892
1893         virtnet_napi_enable(vi->rq[qp_index].vq, &vi->rq[qp_index].napi);
1894         virtnet_napi_tx_enable(vi, vi->sq[qp_index].vq, &vi->sq[qp_index].napi);
1895
1896         return 0;
1897
1898 err_xdp_reg_mem_model:
1899         xdp_rxq_info_unreg(&vi->rq[qp_index].xdp_rxq);
1900         return err;
1901 }
1902
1903 static int virtnet_open(struct net_device *dev)
1904 {
1905         struct virtnet_info *vi = netdev_priv(dev);
1906         int i, err;
1907
1908         enable_delayed_refill(vi);
1909
1910         for (i = 0; i < vi->max_queue_pairs; i++) {
1911                 if (i < vi->curr_queue_pairs)
1912                         /* Make sure we have some buffers: if oom use wq. */
1913                         if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1914                                 schedule_delayed_work(&vi->refill, 0);
1915
1916                 err = virtnet_enable_queue_pair(vi, i);
1917                 if (err < 0)
1918                         goto err_enable_qp;
1919         }
1920
1921         return 0;
1922
1923 err_enable_qp:
1924         disable_delayed_refill(vi);
1925         cancel_delayed_work_sync(&vi->refill);
1926
1927         for (i--; i >= 0; i--)
1928                 virtnet_disable_queue_pair(vi, i);
1929         return err;
1930 }
1931
1932 static int virtnet_poll_tx(struct napi_struct *napi, int budget)
1933 {
1934         struct send_queue *sq = container_of(napi, struct send_queue, napi);
1935         struct virtnet_info *vi = sq->vq->vdev->priv;
1936         unsigned int index = vq2txq(sq->vq);
1937         struct netdev_queue *txq;
1938         int opaque;
1939         bool done;
1940
1941         if (unlikely(is_xdp_raw_buffer_queue(vi, index))) {
1942                 /* We don't need to enable cb for XDP */
1943                 napi_complete_done(napi, 0);
1944                 return 0;
1945         }
1946
1947         txq = netdev_get_tx_queue(vi->dev, index);
1948         __netif_tx_lock(txq, raw_smp_processor_id());
1949         virtqueue_disable_cb(sq->vq);
1950         free_old_xmit_skbs(sq, true);
1951
1952         if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1953                 netif_tx_wake_queue(txq);
1954
1955         opaque = virtqueue_enable_cb_prepare(sq->vq);
1956
1957         done = napi_complete_done(napi, 0);
1958
1959         if (!done)
1960                 virtqueue_disable_cb(sq->vq);
1961
1962         __netif_tx_unlock(txq);
1963
1964         if (done) {
1965                 if (unlikely(virtqueue_poll(sq->vq, opaque))) {
1966                         if (napi_schedule_prep(napi)) {
1967                                 __netif_tx_lock(txq, raw_smp_processor_id());
1968                                 virtqueue_disable_cb(sq->vq);
1969                                 __netif_tx_unlock(txq);
1970                                 __napi_schedule(napi);
1971                         }
1972                 }
1973         }
1974
1975         return 0;
1976 }
1977
1978 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1979 {
1980         struct virtio_net_hdr_mrg_rxbuf *hdr;
1981         const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1982         struct virtnet_info *vi = sq->vq->vdev->priv;
1983         int num_sg;
1984         unsigned hdr_len = vi->hdr_len;
1985         bool can_push;
1986
1987         pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1988
1989         can_push = vi->any_header_sg &&
1990                 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1991                 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1992         /* Even if we can, don't push here yet as this would skew
1993          * csum_start offset below. */
1994         if (can_push)
1995                 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1996         else
1997                 hdr = skb_vnet_hdr(skb);
1998
1999         if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
2000                                     virtio_is_little_endian(vi->vdev), false,
2001                                     0))
2002                 return -EPROTO;
2003
2004         if (vi->mergeable_rx_bufs)
2005                 hdr->num_buffers = 0;
2006
2007         sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
2008         if (can_push) {
2009                 __skb_push(skb, hdr_len);
2010                 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
2011                 if (unlikely(num_sg < 0))
2012                         return num_sg;
2013                 /* Pull header back to avoid skew in tx bytes calculations. */
2014                 __skb_pull(skb, hdr_len);
2015         } else {
2016                 sg_set_buf(sq->sg, hdr, hdr_len);
2017                 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
2018                 if (unlikely(num_sg < 0))
2019                         return num_sg;
2020                 num_sg++;
2021         }
2022         return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
2023 }
2024
2025 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
2026 {
2027         struct virtnet_info *vi = netdev_priv(dev);
2028         int qnum = skb_get_queue_mapping(skb);
2029         struct send_queue *sq = &vi->sq[qnum];
2030         int err;
2031         struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
2032         bool kick = !netdev_xmit_more();
2033         bool use_napi = sq->napi.weight;
2034
2035         /* Free up any pending old buffers before queueing new ones. */
2036         do {
2037                 if (use_napi)
2038                         virtqueue_disable_cb(sq->vq);
2039
2040                 free_old_xmit_skbs(sq, false);
2041
2042         } while (use_napi && kick &&
2043                unlikely(!virtqueue_enable_cb_delayed(sq->vq)));
2044
2045         /* timestamp packet in software */
2046         skb_tx_timestamp(skb);
2047
2048         /* Try to transmit */
2049         err = xmit_skb(sq, skb);
2050
2051         /* This should not happen! */
2052         if (unlikely(err)) {
2053                 dev->stats.tx_fifo_errors++;
2054                 if (net_ratelimit())
2055                         dev_warn(&dev->dev,
2056                                  "Unexpected TXQ (%d) queue failure: %d\n",
2057                                  qnum, err);
2058                 dev->stats.tx_dropped++;
2059                 dev_kfree_skb_any(skb);
2060                 return NETDEV_TX_OK;
2061         }
2062
2063         /* Don't wait up for transmitted skbs to be freed. */
2064         if (!use_napi) {
2065                 skb_orphan(skb);
2066                 nf_reset_ct(skb);
2067         }
2068
2069         check_sq_full_and_disable(vi, dev, sq);
2070
2071         if (kick || netif_xmit_stopped(txq)) {
2072                 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
2073                         u64_stats_update_begin(&sq->stats.syncp);
2074                         sq->stats.kicks++;
2075                         u64_stats_update_end(&sq->stats.syncp);
2076                 }
2077         }
2078
2079         return NETDEV_TX_OK;
2080 }
2081
2082 static int virtnet_rx_resize(struct virtnet_info *vi,
2083                              struct receive_queue *rq, u32 ring_num)
2084 {
2085         bool running = netif_running(vi->dev);
2086         int err, qindex;
2087
2088         qindex = rq - vi->rq;
2089
2090         if (running)
2091                 napi_disable(&rq->napi);
2092
2093         err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_free_unused_buf);
2094         if (err)
2095                 netdev_err(vi->dev, "resize rx fail: rx queue index: %d err: %d\n", qindex, err);
2096
2097         if (!try_fill_recv(vi, rq, GFP_KERNEL))
2098                 schedule_delayed_work(&vi->refill, 0);
2099
2100         if (running)
2101                 virtnet_napi_enable(rq->vq, &rq->napi);
2102         return err;
2103 }
2104
2105 static int virtnet_tx_resize(struct virtnet_info *vi,
2106                              struct send_queue *sq, u32 ring_num)
2107 {
2108         bool running = netif_running(vi->dev);
2109         struct netdev_queue *txq;
2110         int err, qindex;
2111
2112         qindex = sq - vi->sq;
2113
2114         if (running)
2115                 virtnet_napi_tx_disable(&sq->napi);
2116
2117         txq = netdev_get_tx_queue(vi->dev, qindex);
2118
2119         /* 1. wait all ximt complete
2120          * 2. fix the race of netif_stop_subqueue() vs netif_start_subqueue()
2121          */
2122         __netif_tx_lock_bh(txq);
2123
2124         /* Prevent rx poll from accessing sq. */
2125         sq->reset = true;
2126
2127         /* Prevent the upper layer from trying to send packets. */
2128         netif_stop_subqueue(vi->dev, qindex);
2129
2130         __netif_tx_unlock_bh(txq);
2131
2132         err = virtqueue_resize(sq->vq, ring_num, virtnet_sq_free_unused_buf);
2133         if (err)
2134                 netdev_err(vi->dev, "resize tx fail: tx queue index: %d err: %d\n", qindex, err);
2135
2136         __netif_tx_lock_bh(txq);
2137         sq->reset = false;
2138         netif_tx_wake_queue(txq);
2139         __netif_tx_unlock_bh(txq);
2140
2141         if (running)
2142                 virtnet_napi_tx_enable(vi, sq->vq, &sq->napi);
2143         return err;
2144 }
2145
2146 /*
2147  * Send command via the control virtqueue and check status.  Commands
2148  * supported by the hypervisor, as indicated by feature bits, should
2149  * never fail unless improperly formatted.
2150  */
2151 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
2152                                  struct scatterlist *out)
2153 {
2154         struct scatterlist *sgs[4], hdr, stat;
2155         unsigned out_num = 0, tmp;
2156         int ret;
2157
2158         /* Caller should know better */
2159         BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
2160
2161         vi->ctrl->status = ~0;
2162         vi->ctrl->hdr.class = class;
2163         vi->ctrl->hdr.cmd = cmd;
2164         /* Add header */
2165         sg_init_one(&hdr, &vi->ctrl->hdr, sizeof(vi->ctrl->hdr));
2166         sgs[out_num++] = &hdr;
2167
2168         if (out)
2169                 sgs[out_num++] = out;
2170
2171         /* Add return status. */
2172         sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status));
2173         sgs[out_num] = &stat;
2174
2175         BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
2176         ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
2177         if (ret < 0) {
2178                 dev_warn(&vi->vdev->dev,
2179                          "Failed to add sgs for command vq: %d\n.", ret);
2180                 return false;
2181         }
2182
2183         if (unlikely(!virtqueue_kick(vi->cvq)))
2184                 return vi->ctrl->status == VIRTIO_NET_OK;
2185
2186         /* Spin for a response, the kick causes an ioport write, trapping
2187          * into the hypervisor, so the request should be handled immediately.
2188          */
2189         while (!virtqueue_get_buf(vi->cvq, &tmp) &&
2190                !virtqueue_is_broken(vi->cvq))
2191                 cpu_relax();
2192
2193         return vi->ctrl->status == VIRTIO_NET_OK;
2194 }
2195
2196 static int virtnet_set_mac_address(struct net_device *dev, void *p)
2197 {
2198         struct virtnet_info *vi = netdev_priv(dev);
2199         struct virtio_device *vdev = vi->vdev;
2200         int ret;
2201         struct sockaddr *addr;
2202         struct scatterlist sg;
2203
2204         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
2205                 return -EOPNOTSUPP;
2206
2207         addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
2208         if (!addr)
2209                 return -ENOMEM;
2210
2211         ret = eth_prepare_mac_addr_change(dev, addr);
2212         if (ret)
2213                 goto out;
2214
2215         if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
2216                 sg_init_one(&sg, addr->sa_data, dev->addr_len);
2217                 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
2218                                           VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
2219                         dev_warn(&vdev->dev,
2220                                  "Failed to set mac address by vq command.\n");
2221                         ret = -EINVAL;
2222                         goto out;
2223                 }
2224         } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
2225                    !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
2226                 unsigned int i;
2227
2228                 /* Naturally, this has an atomicity problem. */
2229                 for (i = 0; i < dev->addr_len; i++)
2230                         virtio_cwrite8(vdev,
2231                                        offsetof(struct virtio_net_config, mac) +
2232                                        i, addr->sa_data[i]);
2233         }
2234
2235         eth_commit_mac_addr_change(dev, p);
2236         ret = 0;
2237
2238 out:
2239         kfree(addr);
2240         return ret;
2241 }
2242
2243 static void virtnet_stats(struct net_device *dev,
2244                           struct rtnl_link_stats64 *tot)
2245 {
2246         struct virtnet_info *vi = netdev_priv(dev);
2247         unsigned int start;
2248         int i;
2249
2250         for (i = 0; i < vi->max_queue_pairs; i++) {
2251                 u64 tpackets, tbytes, terrors, rpackets, rbytes, rdrops;
2252                 struct receive_queue *rq = &vi->rq[i];
2253                 struct send_queue *sq = &vi->sq[i];
2254
2255                 do {
2256                         start = u64_stats_fetch_begin(&sq->stats.syncp);
2257                         tpackets = sq->stats.packets;
2258                         tbytes   = sq->stats.bytes;
2259                         terrors  = sq->stats.tx_timeouts;
2260                 } while (u64_stats_fetch_retry(&sq->stats.syncp, start));
2261
2262                 do {
2263                         start = u64_stats_fetch_begin(&rq->stats.syncp);
2264                         rpackets = rq->stats.packets;
2265                         rbytes   = rq->stats.bytes;
2266                         rdrops   = rq->stats.drops;
2267                 } while (u64_stats_fetch_retry(&rq->stats.syncp, start));
2268
2269                 tot->rx_packets += rpackets;
2270                 tot->tx_packets += tpackets;
2271                 tot->rx_bytes   += rbytes;
2272                 tot->tx_bytes   += tbytes;
2273                 tot->rx_dropped += rdrops;
2274                 tot->tx_errors  += terrors;
2275         }
2276
2277         tot->tx_dropped = dev->stats.tx_dropped;
2278         tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
2279         tot->rx_length_errors = dev->stats.rx_length_errors;
2280         tot->rx_frame_errors = dev->stats.rx_frame_errors;
2281 }
2282
2283 static void virtnet_ack_link_announce(struct virtnet_info *vi)
2284 {
2285         rtnl_lock();
2286         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
2287                                   VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
2288                 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
2289         rtnl_unlock();
2290 }
2291
2292 static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
2293 {
2294         struct scatterlist sg;
2295         struct net_device *dev = vi->dev;
2296
2297         if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
2298                 return 0;
2299
2300         vi->ctrl->mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
2301         sg_init_one(&sg, &vi->ctrl->mq, sizeof(vi->ctrl->mq));
2302
2303         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
2304                                   VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
2305                 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
2306                          queue_pairs);
2307                 return -EINVAL;
2308         } else {
2309                 vi->curr_queue_pairs = queue_pairs;
2310                 /* virtnet_open() will refill when device is going to up. */
2311                 if (dev->flags & IFF_UP)
2312                         schedule_delayed_work(&vi->refill, 0);
2313         }
2314
2315         return 0;
2316 }
2317
2318 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
2319 {
2320         int err;
2321
2322         rtnl_lock();
2323         err = _virtnet_set_queues(vi, queue_pairs);
2324         rtnl_unlock();
2325         return err;
2326 }
2327
2328 static int virtnet_close(struct net_device *dev)
2329 {
2330         struct virtnet_info *vi = netdev_priv(dev);
2331         int i;
2332
2333         /* Make sure NAPI doesn't schedule refill work */
2334         disable_delayed_refill(vi);
2335         /* Make sure refill_work doesn't re-enable napi! */
2336         cancel_delayed_work_sync(&vi->refill);
2337
2338         for (i = 0; i < vi->max_queue_pairs; i++)
2339                 virtnet_disable_queue_pair(vi, i);
2340
2341         return 0;
2342 }
2343
2344 static void virtnet_set_rx_mode(struct net_device *dev)
2345 {
2346         struct virtnet_info *vi = netdev_priv(dev);
2347         struct scatterlist sg[2];
2348         struct virtio_net_ctrl_mac *mac_data;
2349         struct netdev_hw_addr *ha;
2350         int uc_count;
2351         int mc_count;
2352         void *buf;
2353         int i;
2354
2355         /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
2356         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
2357                 return;
2358
2359         vi->ctrl->promisc = ((dev->flags & IFF_PROMISC) != 0);
2360         vi->ctrl->allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
2361
2362         sg_init_one(sg, &vi->ctrl->promisc, sizeof(vi->ctrl->promisc));
2363
2364         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
2365                                   VIRTIO_NET_CTRL_RX_PROMISC, sg))
2366                 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
2367                          vi->ctrl->promisc ? "en" : "dis");
2368
2369         sg_init_one(sg, &vi->ctrl->allmulti, sizeof(vi->ctrl->allmulti));
2370
2371         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
2372                                   VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
2373                 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
2374                          vi->ctrl->allmulti ? "en" : "dis");
2375
2376         uc_count = netdev_uc_count(dev);
2377         mc_count = netdev_mc_count(dev);
2378         /* MAC filter - use one buffer for both lists */
2379         buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
2380                       (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
2381         mac_data = buf;
2382         if (!buf)
2383                 return;
2384
2385         sg_init_table(sg, 2);
2386
2387         /* Store the unicast list and count in the front of the buffer */
2388         mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
2389         i = 0;
2390         netdev_for_each_uc_addr(ha, dev)
2391                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
2392
2393         sg_set_buf(&sg[0], mac_data,
2394                    sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
2395
2396         /* multicast list and count fill the end */
2397         mac_data = (void *)&mac_data->macs[uc_count][0];
2398
2399         mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
2400         i = 0;
2401         netdev_for_each_mc_addr(ha, dev)
2402                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
2403
2404         sg_set_buf(&sg[1], mac_data,
2405                    sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
2406
2407         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
2408                                   VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
2409                 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
2410
2411         kfree(buf);
2412 }
2413
2414 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
2415                                    __be16 proto, u16 vid)
2416 {
2417         struct virtnet_info *vi = netdev_priv(dev);
2418         struct scatterlist sg;
2419
2420         vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
2421         sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
2422
2423         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
2424                                   VIRTIO_NET_CTRL_VLAN_ADD, &sg))
2425                 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
2426         return 0;
2427 }
2428
2429 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
2430                                     __be16 proto, u16 vid)
2431 {
2432         struct virtnet_info *vi = netdev_priv(dev);
2433         struct scatterlist sg;
2434
2435         vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
2436         sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
2437
2438         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
2439                                   VIRTIO_NET_CTRL_VLAN_DEL, &sg))
2440                 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
2441         return 0;
2442 }
2443
2444 static void virtnet_clean_affinity(struct virtnet_info *vi)
2445 {
2446         int i;
2447
2448         if (vi->affinity_hint_set) {
2449                 for (i = 0; i < vi->max_queue_pairs; i++) {
2450                         virtqueue_set_affinity(vi->rq[i].vq, NULL);
2451                         virtqueue_set_affinity(vi->sq[i].vq, NULL);
2452                 }
2453
2454                 vi->affinity_hint_set = false;
2455         }
2456 }
2457
2458 static void virtnet_set_affinity(struct virtnet_info *vi)
2459 {
2460         cpumask_var_t mask;
2461         int stragglers;
2462         int group_size;
2463         int i, j, cpu;
2464         int num_cpu;
2465         int stride;
2466
2467         if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) {
2468                 virtnet_clean_affinity(vi);
2469                 return;
2470         }
2471
2472         num_cpu = num_online_cpus();
2473         stride = max_t(int, num_cpu / vi->curr_queue_pairs, 1);
2474         stragglers = num_cpu >= vi->curr_queue_pairs ?
2475                         num_cpu % vi->curr_queue_pairs :
2476                         0;
2477         cpu = cpumask_first(cpu_online_mask);
2478
2479         for (i = 0; i < vi->curr_queue_pairs; i++) {
2480                 group_size = stride + (i < stragglers ? 1 : 0);
2481
2482                 for (j = 0; j < group_size; j++) {
2483                         cpumask_set_cpu(cpu, mask);
2484                         cpu = cpumask_next_wrap(cpu, cpu_online_mask,
2485                                                 nr_cpu_ids, false);
2486                 }
2487                 virtqueue_set_affinity(vi->rq[i].vq, mask);
2488                 virtqueue_set_affinity(vi->sq[i].vq, mask);
2489                 __netif_set_xps_queue(vi->dev, cpumask_bits(mask), i, XPS_CPUS);
2490                 cpumask_clear(mask);
2491         }
2492
2493         vi->affinity_hint_set = true;
2494         free_cpumask_var(mask);
2495 }
2496
2497 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
2498 {
2499         struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
2500                                                    node);
2501         virtnet_set_affinity(vi);
2502         return 0;
2503 }
2504
2505 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
2506 {
2507         struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
2508                                                    node_dead);
2509         virtnet_set_affinity(vi);
2510         return 0;
2511 }
2512
2513 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
2514 {
2515         struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
2516                                                    node);
2517
2518         virtnet_clean_affinity(vi);
2519         return 0;
2520 }
2521
2522 static enum cpuhp_state virtionet_online;
2523
2524 static int virtnet_cpu_notif_add(struct virtnet_info *vi)
2525 {
2526         int ret;
2527
2528         ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
2529         if (ret)
2530                 return ret;
2531         ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
2532                                                &vi->node_dead);
2533         if (!ret)
2534                 return ret;
2535         cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
2536         return ret;
2537 }
2538
2539 static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
2540 {
2541         cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
2542         cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
2543                                             &vi->node_dead);
2544 }
2545
2546 static void virtnet_get_ringparam(struct net_device *dev,
2547                                   struct ethtool_ringparam *ring,
2548                                   struct kernel_ethtool_ringparam *kernel_ring,
2549                                   struct netlink_ext_ack *extack)
2550 {
2551         struct virtnet_info *vi = netdev_priv(dev);
2552
2553         ring->rx_max_pending = vi->rq[0].vq->num_max;
2554         ring->tx_max_pending = vi->sq[0].vq->num_max;
2555         ring->rx_pending = virtqueue_get_vring_size(vi->rq[0].vq);
2556         ring->tx_pending = virtqueue_get_vring_size(vi->sq[0].vq);
2557 }
2558
2559 static int virtnet_set_ringparam(struct net_device *dev,
2560                                  struct ethtool_ringparam *ring,
2561                                  struct kernel_ethtool_ringparam *kernel_ring,
2562                                  struct netlink_ext_ack *extack)
2563 {
2564         struct virtnet_info *vi = netdev_priv(dev);
2565         u32 rx_pending, tx_pending;
2566         struct receive_queue *rq;
2567         struct send_queue *sq;
2568         int i, err;
2569
2570         if (ring->rx_mini_pending || ring->rx_jumbo_pending)
2571                 return -EINVAL;
2572
2573         rx_pending = virtqueue_get_vring_size(vi->rq[0].vq);
2574         tx_pending = virtqueue_get_vring_size(vi->sq[0].vq);
2575
2576         if (ring->rx_pending == rx_pending &&
2577             ring->tx_pending == tx_pending)
2578                 return 0;
2579
2580         if (ring->rx_pending > vi->rq[0].vq->num_max)
2581                 return -EINVAL;
2582
2583         if (ring->tx_pending > vi->sq[0].vq->num_max)
2584                 return -EINVAL;
2585
2586         for (i = 0; i < vi->max_queue_pairs; i++) {
2587                 rq = vi->rq + i;
2588                 sq = vi->sq + i;
2589
2590                 if (ring->tx_pending != tx_pending) {
2591                         err = virtnet_tx_resize(vi, sq, ring->tx_pending);
2592                         if (err)
2593                                 return err;
2594                 }
2595
2596                 if (ring->rx_pending != rx_pending) {
2597                         err = virtnet_rx_resize(vi, rq, ring->rx_pending);
2598                         if (err)
2599                                 return err;
2600                 }
2601         }
2602
2603         return 0;
2604 }
2605
2606 static bool virtnet_commit_rss_command(struct virtnet_info *vi)
2607 {
2608         struct net_device *dev = vi->dev;
2609         struct scatterlist sgs[4];
2610         unsigned int sg_buf_size;
2611
2612         /* prepare sgs */
2613         sg_init_table(sgs, 4);
2614
2615         sg_buf_size = offsetof(struct virtio_net_ctrl_rss, indirection_table);
2616         sg_set_buf(&sgs[0], &vi->ctrl->rss, sg_buf_size);
2617
2618         sg_buf_size = sizeof(uint16_t) * (vi->ctrl->rss.indirection_table_mask + 1);
2619         sg_set_buf(&sgs[1], vi->ctrl->rss.indirection_table, sg_buf_size);
2620
2621         sg_buf_size = offsetof(struct virtio_net_ctrl_rss, key)
2622                         - offsetof(struct virtio_net_ctrl_rss, max_tx_vq);
2623         sg_set_buf(&sgs[2], &vi->ctrl->rss.max_tx_vq, sg_buf_size);
2624
2625         sg_buf_size = vi->rss_key_size;
2626         sg_set_buf(&sgs[3], vi->ctrl->rss.key, sg_buf_size);
2627
2628         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
2629                                   vi->has_rss ? VIRTIO_NET_CTRL_MQ_RSS_CONFIG
2630                                   : VIRTIO_NET_CTRL_MQ_HASH_CONFIG, sgs)) {
2631                 dev_warn(&dev->dev, "VIRTIONET issue with committing RSS sgs\n");
2632                 return false;
2633         }
2634         return true;
2635 }
2636
2637 static void virtnet_init_default_rss(struct virtnet_info *vi)
2638 {
2639         u32 indir_val = 0;
2640         int i = 0;
2641
2642         vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
2643         vi->rss_hash_types_saved = vi->rss_hash_types_supported;
2644         vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size
2645                                                 ? vi->rss_indir_table_size - 1 : 0;
2646         vi->ctrl->rss.unclassified_queue = 0;
2647
2648         for (; i < vi->rss_indir_table_size; ++i) {
2649                 indir_val = ethtool_rxfh_indir_default(i, vi->curr_queue_pairs);
2650                 vi->ctrl->rss.indirection_table[i] = indir_val;
2651         }
2652
2653         vi->ctrl->rss.max_tx_vq = vi->curr_queue_pairs;
2654         vi->ctrl->rss.hash_key_length = vi->rss_key_size;
2655
2656         netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
2657 }
2658
2659 static void virtnet_get_hashflow(const struct virtnet_info *vi, struct ethtool_rxnfc *info)
2660 {
2661         info->data = 0;
2662         switch (info->flow_type) {
2663         case TCP_V4_FLOW:
2664                 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) {
2665                         info->data = RXH_IP_SRC | RXH_IP_DST |
2666                                                  RXH_L4_B_0_1 | RXH_L4_B_2_3;
2667                 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
2668                         info->data = RXH_IP_SRC | RXH_IP_DST;
2669                 }
2670                 break;
2671         case TCP_V6_FLOW:
2672                 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) {
2673                         info->data = RXH_IP_SRC | RXH_IP_DST |
2674                                                  RXH_L4_B_0_1 | RXH_L4_B_2_3;
2675                 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
2676                         info->data = RXH_IP_SRC | RXH_IP_DST;
2677                 }
2678                 break;
2679         case UDP_V4_FLOW:
2680                 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) {
2681                         info->data = RXH_IP_SRC | RXH_IP_DST |
2682                                                  RXH_L4_B_0_1 | RXH_L4_B_2_3;
2683                 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
2684                         info->data = RXH_IP_SRC | RXH_IP_DST;
2685                 }
2686                 break;
2687         case UDP_V6_FLOW:
2688                 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) {
2689                         info->data = RXH_IP_SRC | RXH_IP_DST |
2690                                                  RXH_L4_B_0_1 | RXH_L4_B_2_3;
2691                 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
2692                         info->data = RXH_IP_SRC | RXH_IP_DST;
2693                 }
2694                 break;
2695         case IPV4_FLOW:
2696                 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
2697                         info->data = RXH_IP_SRC | RXH_IP_DST;
2698
2699                 break;
2700         case IPV6_FLOW:
2701                 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6)
2702                         info->data = RXH_IP_SRC | RXH_IP_DST;
2703
2704                 break;
2705         default:
2706                 info->data = 0;
2707                 break;
2708         }
2709 }
2710
2711 static bool virtnet_set_hashflow(struct virtnet_info *vi, struct ethtool_rxnfc *info)
2712 {
2713         u32 new_hashtypes = vi->rss_hash_types_saved;
2714         bool is_disable = info->data & RXH_DISCARD;
2715         bool is_l4 = info->data == (RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3);
2716
2717         /* supports only 'sd', 'sdfn' and 'r' */
2718         if (!((info->data == (RXH_IP_SRC | RXH_IP_DST)) | is_l4 | is_disable))
2719                 return false;
2720
2721         switch (info->flow_type) {
2722         case TCP_V4_FLOW:
2723                 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_TCPv4);
2724                 if (!is_disable)
2725                         new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
2726                                 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv4 : 0);
2727                 break;
2728         case UDP_V4_FLOW:
2729                 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_UDPv4);
2730                 if (!is_disable)
2731                         new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
2732                                 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv4 : 0);
2733                 break;
2734         case IPV4_FLOW:
2735                 new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
2736                 if (!is_disable)
2737                         new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv4;
2738                 break;
2739         case TCP_V6_FLOW:
2740                 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_TCPv6);
2741                 if (!is_disable)
2742                         new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
2743                                 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv6 : 0);
2744                 break;
2745         case UDP_V6_FLOW:
2746                 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_UDPv6);
2747                 if (!is_disable)
2748                         new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
2749                                 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv6 : 0);
2750                 break;
2751         case IPV6_FLOW:
2752                 new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
2753                 if (!is_disable)
2754                         new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv6;
2755                 break;
2756         default:
2757                 /* unsupported flow */
2758                 return false;
2759         }
2760
2761         /* if unsupported hashtype was set */
2762         if (new_hashtypes != (new_hashtypes & vi->rss_hash_types_supported))
2763                 return false;
2764
2765         if (new_hashtypes != vi->rss_hash_types_saved) {
2766                 vi->rss_hash_types_saved = new_hashtypes;
2767                 vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
2768                 if (vi->dev->features & NETIF_F_RXHASH)
2769                         return virtnet_commit_rss_command(vi);
2770         }
2771
2772         return true;
2773 }
2774
2775 static void virtnet_get_drvinfo(struct net_device *dev,
2776                                 struct ethtool_drvinfo *info)
2777 {
2778         struct virtnet_info *vi = netdev_priv(dev);
2779         struct virtio_device *vdev = vi->vdev;
2780
2781         strscpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
2782         strscpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
2783         strscpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
2784
2785 }
2786
2787 /* TODO: Eliminate OOO packets during switching */
2788 static int virtnet_set_channels(struct net_device *dev,
2789                                 struct ethtool_channels *channels)
2790 {
2791         struct virtnet_info *vi = netdev_priv(dev);
2792         u16 queue_pairs = channels->combined_count;
2793         int err;
2794
2795         /* We don't support separate rx/tx channels.
2796          * We don't allow setting 'other' channels.
2797          */
2798         if (channels->rx_count || channels->tx_count || channels->other_count)
2799                 return -EINVAL;
2800
2801         if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
2802                 return -EINVAL;
2803
2804         /* For now we don't support modifying channels while XDP is loaded
2805          * also when XDP is loaded all RX queues have XDP programs so we only
2806          * need to check a single RX queue.
2807          */
2808         if (vi->rq[0].xdp_prog)
2809                 return -EINVAL;
2810
2811         cpus_read_lock();
2812         err = _virtnet_set_queues(vi, queue_pairs);
2813         if (err) {
2814                 cpus_read_unlock();
2815                 goto err;
2816         }
2817         virtnet_set_affinity(vi);
2818         cpus_read_unlock();
2819
2820         netif_set_real_num_tx_queues(dev, queue_pairs);
2821         netif_set_real_num_rx_queues(dev, queue_pairs);
2822  err:
2823         return err;
2824 }
2825
2826 static void virtnet_get_strings(struct net_device *dev, u32 stringset, u8 *data)
2827 {
2828         struct virtnet_info *vi = netdev_priv(dev);
2829         unsigned int i, j;
2830         u8 *p = data;
2831
2832         switch (stringset) {
2833         case ETH_SS_STATS:
2834                 for (i = 0; i < vi->curr_queue_pairs; i++) {
2835                         for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++)
2836                                 ethtool_sprintf(&p, "rx_queue_%u_%s", i,
2837                                                 virtnet_rq_stats_desc[j].desc);
2838                 }
2839
2840                 for (i = 0; i < vi->curr_queue_pairs; i++) {
2841                         for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++)
2842                                 ethtool_sprintf(&p, "tx_queue_%u_%s", i,
2843                                                 virtnet_sq_stats_desc[j].desc);
2844                 }
2845                 break;
2846         }
2847 }
2848
2849 static int virtnet_get_sset_count(struct net_device *dev, int sset)
2850 {
2851         struct virtnet_info *vi = netdev_priv(dev);
2852
2853         switch (sset) {
2854         case ETH_SS_STATS:
2855                 return vi->curr_queue_pairs * (VIRTNET_RQ_STATS_LEN +
2856                                                VIRTNET_SQ_STATS_LEN);
2857         default:
2858                 return -EOPNOTSUPP;
2859         }
2860 }
2861
2862 static void virtnet_get_ethtool_stats(struct net_device *dev,
2863                                       struct ethtool_stats *stats, u64 *data)
2864 {
2865         struct virtnet_info *vi = netdev_priv(dev);
2866         unsigned int idx = 0, start, i, j;
2867         const u8 *stats_base;
2868         size_t offset;
2869
2870         for (i = 0; i < vi->curr_queue_pairs; i++) {
2871                 struct receive_queue *rq = &vi->rq[i];
2872
2873                 stats_base = (u8 *)&rq->stats;
2874                 do {
2875                         start = u64_stats_fetch_begin(&rq->stats.syncp);
2876                         for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
2877                                 offset = virtnet_rq_stats_desc[j].offset;
2878                                 data[idx + j] = *(u64 *)(stats_base + offset);
2879                         }
2880                 } while (u64_stats_fetch_retry(&rq->stats.syncp, start));
2881                 idx += VIRTNET_RQ_STATS_LEN;
2882         }
2883
2884         for (i = 0; i < vi->curr_queue_pairs; i++) {
2885                 struct send_queue *sq = &vi->sq[i];
2886
2887                 stats_base = (u8 *)&sq->stats;
2888                 do {
2889                         start = u64_stats_fetch_begin(&sq->stats.syncp);
2890                         for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
2891                                 offset = virtnet_sq_stats_desc[j].offset;
2892                                 data[idx + j] = *(u64 *)(stats_base + offset);
2893                         }
2894                 } while (u64_stats_fetch_retry(&sq->stats.syncp, start));
2895                 idx += VIRTNET_SQ_STATS_LEN;
2896         }
2897 }
2898
2899 static void virtnet_get_channels(struct net_device *dev,
2900                                  struct ethtool_channels *channels)
2901 {
2902         struct virtnet_info *vi = netdev_priv(dev);
2903
2904         channels->combined_count = vi->curr_queue_pairs;
2905         channels->max_combined = vi->max_queue_pairs;
2906         channels->max_other = 0;
2907         channels->rx_count = 0;
2908         channels->tx_count = 0;
2909         channels->other_count = 0;
2910 }
2911
2912 static int virtnet_set_link_ksettings(struct net_device *dev,
2913                                       const struct ethtool_link_ksettings *cmd)
2914 {
2915         struct virtnet_info *vi = netdev_priv(dev);
2916
2917         return ethtool_virtdev_set_link_ksettings(dev, cmd,
2918                                                   &vi->speed, &vi->duplex);
2919 }
2920
2921 static int virtnet_get_link_ksettings(struct net_device *dev,
2922                                       struct ethtool_link_ksettings *cmd)
2923 {
2924         struct virtnet_info *vi = netdev_priv(dev);
2925
2926         cmd->base.speed = vi->speed;
2927         cmd->base.duplex = vi->duplex;
2928         cmd->base.port = PORT_OTHER;
2929
2930         return 0;
2931 }
2932
2933 static int virtnet_send_notf_coal_cmds(struct virtnet_info *vi,
2934                                        struct ethtool_coalesce *ec)
2935 {
2936         struct scatterlist sgs_tx, sgs_rx;
2937         struct virtio_net_ctrl_coal_tx coal_tx;
2938         struct virtio_net_ctrl_coal_rx coal_rx;
2939
2940         coal_tx.tx_usecs = cpu_to_le32(ec->tx_coalesce_usecs);
2941         coal_tx.tx_max_packets = cpu_to_le32(ec->tx_max_coalesced_frames);
2942         sg_init_one(&sgs_tx, &coal_tx, sizeof(coal_tx));
2943
2944         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
2945                                   VIRTIO_NET_CTRL_NOTF_COAL_TX_SET,
2946                                   &sgs_tx))
2947                 return -EINVAL;
2948
2949         /* Save parameters */
2950         vi->tx_usecs = ec->tx_coalesce_usecs;
2951         vi->tx_max_packets = ec->tx_max_coalesced_frames;
2952
2953         coal_rx.rx_usecs = cpu_to_le32(ec->rx_coalesce_usecs);
2954         coal_rx.rx_max_packets = cpu_to_le32(ec->rx_max_coalesced_frames);
2955         sg_init_one(&sgs_rx, &coal_rx, sizeof(coal_rx));
2956
2957         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
2958                                   VIRTIO_NET_CTRL_NOTF_COAL_RX_SET,
2959                                   &sgs_rx))
2960                 return -EINVAL;
2961
2962         /* Save parameters */
2963         vi->rx_usecs = ec->rx_coalesce_usecs;
2964         vi->rx_max_packets = ec->rx_max_coalesced_frames;
2965
2966         return 0;
2967 }
2968
2969 static int virtnet_coal_params_supported(struct ethtool_coalesce *ec)
2970 {
2971         /* usecs coalescing is supported only if VIRTIO_NET_F_NOTF_COAL
2972          * feature is negotiated.
2973          */
2974         if (ec->rx_coalesce_usecs || ec->tx_coalesce_usecs)
2975                 return -EOPNOTSUPP;
2976
2977         if (ec->tx_max_coalesced_frames > 1 ||
2978             ec->rx_max_coalesced_frames != 1)
2979                 return -EINVAL;
2980
2981         return 0;
2982 }
2983
2984 static int virtnet_set_coalesce(struct net_device *dev,
2985                                 struct ethtool_coalesce *ec,
2986                                 struct kernel_ethtool_coalesce *kernel_coal,
2987                                 struct netlink_ext_ack *extack)
2988 {
2989         struct virtnet_info *vi = netdev_priv(dev);
2990         int ret, i, napi_weight;
2991         bool update_napi = false;
2992
2993         /* Can't change NAPI weight if the link is up */
2994         napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
2995         if (napi_weight ^ vi->sq[0].napi.weight) {
2996                 if (dev->flags & IFF_UP)
2997                         return -EBUSY;
2998                 else
2999                         update_napi = true;
3000         }
3001
3002         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL))
3003                 ret = virtnet_send_notf_coal_cmds(vi, ec);
3004         else
3005                 ret = virtnet_coal_params_supported(ec);
3006
3007         if (ret)
3008                 return ret;
3009
3010         if (update_napi) {
3011                 for (i = 0; i < vi->max_queue_pairs; i++)
3012                         vi->sq[i].napi.weight = napi_weight;
3013         }
3014
3015         return ret;
3016 }
3017
3018 static int virtnet_get_coalesce(struct net_device *dev,
3019                                 struct ethtool_coalesce *ec,
3020                                 struct kernel_ethtool_coalesce *kernel_coal,
3021                                 struct netlink_ext_ack *extack)
3022 {
3023         struct virtnet_info *vi = netdev_priv(dev);
3024
3025         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) {
3026                 ec->rx_coalesce_usecs = vi->rx_usecs;
3027                 ec->tx_coalesce_usecs = vi->tx_usecs;
3028                 ec->tx_max_coalesced_frames = vi->tx_max_packets;
3029                 ec->rx_max_coalesced_frames = vi->rx_max_packets;
3030         } else {
3031                 ec->rx_max_coalesced_frames = 1;
3032
3033                 if (vi->sq[0].napi.weight)
3034                         ec->tx_max_coalesced_frames = 1;
3035         }
3036
3037         return 0;
3038 }
3039
3040 static void virtnet_init_settings(struct net_device *dev)
3041 {
3042         struct virtnet_info *vi = netdev_priv(dev);
3043
3044         vi->speed = SPEED_UNKNOWN;
3045         vi->duplex = DUPLEX_UNKNOWN;
3046 }
3047
3048 static void virtnet_update_settings(struct virtnet_info *vi)
3049 {
3050         u32 speed;
3051         u8 duplex;
3052
3053         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX))
3054                 return;
3055
3056         virtio_cread_le(vi->vdev, struct virtio_net_config, speed, &speed);
3057
3058         if (ethtool_validate_speed(speed))
3059                 vi->speed = speed;
3060
3061         virtio_cread_le(vi->vdev, struct virtio_net_config, duplex, &duplex);
3062
3063         if (ethtool_validate_duplex(duplex))
3064                 vi->duplex = duplex;
3065 }
3066
3067 static u32 virtnet_get_rxfh_key_size(struct net_device *dev)
3068 {
3069         return ((struct virtnet_info *)netdev_priv(dev))->rss_key_size;
3070 }
3071
3072 static u32 virtnet_get_rxfh_indir_size(struct net_device *dev)
3073 {
3074         return ((struct virtnet_info *)netdev_priv(dev))->rss_indir_table_size;
3075 }
3076
3077 static int virtnet_get_rxfh(struct net_device *dev, u32 *indir, u8 *key, u8 *hfunc)
3078 {
3079         struct virtnet_info *vi = netdev_priv(dev);
3080         int i;
3081
3082         if (indir) {
3083                 for (i = 0; i < vi->rss_indir_table_size; ++i)
3084                         indir[i] = vi->ctrl->rss.indirection_table[i];
3085         }
3086
3087         if (key)
3088                 memcpy(key, vi->ctrl->rss.key, vi->rss_key_size);
3089
3090         if (hfunc)
3091                 *hfunc = ETH_RSS_HASH_TOP;
3092
3093         return 0;
3094 }
3095
3096 static int virtnet_set_rxfh(struct net_device *dev, const u32 *indir, const u8 *key, const u8 hfunc)
3097 {
3098         struct virtnet_info *vi = netdev_priv(dev);
3099         int i;
3100
3101         if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
3102                 return -EOPNOTSUPP;
3103
3104         if (indir) {
3105                 for (i = 0; i < vi->rss_indir_table_size; ++i)
3106                         vi->ctrl->rss.indirection_table[i] = indir[i];
3107         }
3108         if (key)
3109                 memcpy(vi->ctrl->rss.key, key, vi->rss_key_size);
3110
3111         virtnet_commit_rss_command(vi);
3112
3113         return 0;
3114 }
3115
3116 static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info, u32 *rule_locs)
3117 {
3118         struct virtnet_info *vi = netdev_priv(dev);
3119         int rc = 0;
3120
3121         switch (info->cmd) {
3122         case ETHTOOL_GRXRINGS:
3123                 info->data = vi->curr_queue_pairs;
3124                 break;
3125         case ETHTOOL_GRXFH:
3126                 virtnet_get_hashflow(vi, info);
3127                 break;
3128         default:
3129                 rc = -EOPNOTSUPP;
3130         }
3131
3132         return rc;
3133 }
3134
3135 static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info)
3136 {
3137         struct virtnet_info *vi = netdev_priv(dev);
3138         int rc = 0;
3139
3140         switch (info->cmd) {
3141         case ETHTOOL_SRXFH:
3142                 if (!virtnet_set_hashflow(vi, info))
3143                         rc = -EINVAL;
3144
3145                 break;
3146         default:
3147                 rc = -EOPNOTSUPP;
3148         }
3149
3150         return rc;
3151 }
3152
3153 static const struct ethtool_ops virtnet_ethtool_ops = {
3154         .supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES |
3155                 ETHTOOL_COALESCE_USECS,
3156         .get_drvinfo = virtnet_get_drvinfo,
3157         .get_link = ethtool_op_get_link,
3158         .get_ringparam = virtnet_get_ringparam,
3159         .set_ringparam = virtnet_set_ringparam,
3160         .get_strings = virtnet_get_strings,
3161         .get_sset_count = virtnet_get_sset_count,
3162         .get_ethtool_stats = virtnet_get_ethtool_stats,
3163         .set_channels = virtnet_set_channels,
3164         .get_channels = virtnet_get_channels,
3165         .get_ts_info = ethtool_op_get_ts_info,
3166         .get_link_ksettings = virtnet_get_link_ksettings,
3167         .set_link_ksettings = virtnet_set_link_ksettings,
3168         .set_coalesce = virtnet_set_coalesce,
3169         .get_coalesce = virtnet_get_coalesce,
3170         .get_rxfh_key_size = virtnet_get_rxfh_key_size,
3171         .get_rxfh_indir_size = virtnet_get_rxfh_indir_size,
3172         .get_rxfh = virtnet_get_rxfh,
3173         .set_rxfh = virtnet_set_rxfh,
3174         .get_rxnfc = virtnet_get_rxnfc,
3175         .set_rxnfc = virtnet_set_rxnfc,
3176 };
3177
3178 static void virtnet_freeze_down(struct virtio_device *vdev)
3179 {
3180         struct virtnet_info *vi = vdev->priv;
3181
3182         /* Make sure no work handler is accessing the device */
3183         flush_work(&vi->config_work);
3184
3185         netif_tx_lock_bh(vi->dev);
3186         netif_device_detach(vi->dev);
3187         netif_tx_unlock_bh(vi->dev);
3188         if (netif_running(vi->dev))
3189                 virtnet_close(vi->dev);
3190 }
3191
3192 static int init_vqs(struct virtnet_info *vi);
3193
3194 static int virtnet_restore_up(struct virtio_device *vdev)
3195 {
3196         struct virtnet_info *vi = vdev->priv;
3197         int err;
3198
3199         err = init_vqs(vi);
3200         if (err)
3201                 return err;
3202
3203         virtio_device_ready(vdev);
3204
3205         enable_delayed_refill(vi);
3206
3207         if (netif_running(vi->dev)) {
3208                 err = virtnet_open(vi->dev);
3209                 if (err)
3210                         return err;
3211         }
3212
3213         netif_tx_lock_bh(vi->dev);
3214         netif_device_attach(vi->dev);
3215         netif_tx_unlock_bh(vi->dev);
3216         return err;
3217 }
3218
3219 static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
3220 {
3221         struct scatterlist sg;
3222         vi->ctrl->offloads = cpu_to_virtio64(vi->vdev, offloads);
3223
3224         sg_init_one(&sg, &vi->ctrl->offloads, sizeof(vi->ctrl->offloads));
3225
3226         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
3227                                   VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
3228                 dev_warn(&vi->dev->dev, "Fail to set guest offload.\n");
3229                 return -EINVAL;
3230         }
3231
3232         return 0;
3233 }
3234
3235 static int virtnet_clear_guest_offloads(struct virtnet_info *vi)
3236 {
3237         u64 offloads = 0;
3238
3239         if (!vi->guest_offloads)
3240                 return 0;
3241
3242         return virtnet_set_guest_offloads(vi, offloads);
3243 }
3244
3245 static int virtnet_restore_guest_offloads(struct virtnet_info *vi)
3246 {
3247         u64 offloads = vi->guest_offloads;
3248
3249         if (!vi->guest_offloads)
3250                 return 0;
3251
3252         return virtnet_set_guest_offloads(vi, offloads);
3253 }
3254
3255 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
3256                            struct netlink_ext_ack *extack)
3257 {
3258         unsigned int room = SKB_DATA_ALIGN(VIRTIO_XDP_HEADROOM +
3259                                            sizeof(struct skb_shared_info));
3260         unsigned int max_sz = PAGE_SIZE - room - ETH_HLEN;
3261         struct virtnet_info *vi = netdev_priv(dev);
3262         struct bpf_prog *old_prog;
3263         u16 xdp_qp = 0, curr_qp;
3264         int i, err;
3265
3266         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)
3267             && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3268                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
3269                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
3270                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) ||
3271                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM) ||
3272                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO4) ||
3273                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO6))) {
3274                 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing GRO_HW/CSUM, disable GRO_HW/CSUM first");
3275                 return -EOPNOTSUPP;
3276         }
3277
3278         if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
3279                 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
3280                 return -EINVAL;
3281         }
3282
3283         if (prog && !prog->aux->xdp_has_frags && dev->mtu > max_sz) {
3284                 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP without frags");
3285                 netdev_warn(dev, "single-buffer XDP requires MTU less than %u\n", max_sz);
3286                 return -EINVAL;
3287         }
3288
3289         curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
3290         if (prog)
3291                 xdp_qp = nr_cpu_ids;
3292
3293         /* XDP requires extra queues for XDP_TX */
3294         if (curr_qp + xdp_qp > vi->max_queue_pairs) {
3295                 netdev_warn_once(dev, "XDP request %i queues but max is %i. XDP_TX and XDP_REDIRECT will operate in a slower locked tx mode.\n",
3296                                  curr_qp + xdp_qp, vi->max_queue_pairs);
3297                 xdp_qp = 0;
3298         }
3299
3300         old_prog = rtnl_dereference(vi->rq[0].xdp_prog);
3301         if (!prog && !old_prog)
3302                 return 0;
3303
3304         if (prog)
3305                 bpf_prog_add(prog, vi->max_queue_pairs - 1);
3306
3307         /* Make sure NAPI is not using any XDP TX queues for RX. */
3308         if (netif_running(dev)) {
3309                 for (i = 0; i < vi->max_queue_pairs; i++) {
3310                         napi_disable(&vi->rq[i].napi);
3311                         virtnet_napi_tx_disable(&vi->sq[i].napi);
3312                 }
3313         }
3314
3315         if (!prog) {
3316                 for (i = 0; i < vi->max_queue_pairs; i++) {
3317                         rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
3318                         if (i == 0)
3319                                 virtnet_restore_guest_offloads(vi);
3320                 }
3321                 synchronize_net();
3322         }
3323
3324         err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
3325         if (err)
3326                 goto err;
3327         netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
3328         vi->xdp_queue_pairs = xdp_qp;
3329
3330         if (prog) {
3331                 vi->xdp_enabled = true;
3332                 for (i = 0; i < vi->max_queue_pairs; i++) {
3333                         rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
3334                         if (i == 0 && !old_prog)
3335                                 virtnet_clear_guest_offloads(vi);
3336                 }
3337                 if (!old_prog)
3338                         xdp_features_set_redirect_target(dev, true);
3339         } else {
3340                 xdp_features_clear_redirect_target(dev);
3341                 vi->xdp_enabled = false;
3342         }
3343
3344         for (i = 0; i < vi->max_queue_pairs; i++) {
3345                 if (old_prog)
3346                         bpf_prog_put(old_prog);
3347                 if (netif_running(dev)) {
3348                         virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
3349                         virtnet_napi_tx_enable(vi, vi->sq[i].vq,
3350                                                &vi->sq[i].napi);
3351                 }
3352         }
3353
3354         return 0;
3355
3356 err:
3357         if (!prog) {
3358                 virtnet_clear_guest_offloads(vi);
3359                 for (i = 0; i < vi->max_queue_pairs; i++)
3360                         rcu_assign_pointer(vi->rq[i].xdp_prog, old_prog);
3361         }
3362
3363         if (netif_running(dev)) {
3364                 for (i = 0; i < vi->max_queue_pairs; i++) {
3365                         virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
3366                         virtnet_napi_tx_enable(vi, vi->sq[i].vq,
3367                                                &vi->sq[i].napi);
3368                 }
3369         }
3370         if (prog)
3371                 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
3372         return err;
3373 }
3374
3375 static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
3376 {
3377         switch (xdp->command) {
3378         case XDP_SETUP_PROG:
3379                 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
3380         default:
3381                 return -EINVAL;
3382         }
3383 }
3384
3385 static int virtnet_get_phys_port_name(struct net_device *dev, char *buf,
3386                                       size_t len)
3387 {
3388         struct virtnet_info *vi = netdev_priv(dev);
3389         int ret;
3390
3391         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
3392                 return -EOPNOTSUPP;
3393
3394         ret = snprintf(buf, len, "sby");
3395         if (ret >= len)
3396                 return -EOPNOTSUPP;
3397
3398         return 0;
3399 }
3400
3401 static int virtnet_set_features(struct net_device *dev,
3402                                 netdev_features_t features)
3403 {
3404         struct virtnet_info *vi = netdev_priv(dev);
3405         u64 offloads;
3406         int err;
3407
3408         if ((dev->features ^ features) & NETIF_F_GRO_HW) {
3409                 if (vi->xdp_enabled)
3410                         return -EBUSY;
3411
3412                 if (features & NETIF_F_GRO_HW)
3413                         offloads = vi->guest_offloads_capable;
3414                 else
3415                         offloads = vi->guest_offloads_capable &
3416                                    ~GUEST_OFFLOAD_GRO_HW_MASK;
3417
3418                 err = virtnet_set_guest_offloads(vi, offloads);
3419                 if (err)
3420                         return err;
3421                 vi->guest_offloads = offloads;
3422         }
3423
3424         if ((dev->features ^ features) & NETIF_F_RXHASH) {
3425                 if (features & NETIF_F_RXHASH)
3426                         vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
3427                 else
3428                         vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
3429
3430                 if (!virtnet_commit_rss_command(vi))
3431                         return -EINVAL;
3432         }
3433
3434         return 0;
3435 }
3436
3437 static void virtnet_tx_timeout(struct net_device *dev, unsigned int txqueue)
3438 {
3439         struct virtnet_info *priv = netdev_priv(dev);
3440         struct send_queue *sq = &priv->sq[txqueue];
3441         struct netdev_queue *txq = netdev_get_tx_queue(dev, txqueue);
3442
3443         u64_stats_update_begin(&sq->stats.syncp);
3444         sq->stats.tx_timeouts++;
3445         u64_stats_update_end(&sq->stats.syncp);
3446
3447         netdev_err(dev, "TX timeout on queue: %u, sq: %s, vq: 0x%x, name: %s, %u usecs ago\n",
3448                    txqueue, sq->name, sq->vq->index, sq->vq->name,
3449                    jiffies_to_usecs(jiffies - READ_ONCE(txq->trans_start)));
3450 }
3451
3452 static const struct net_device_ops virtnet_netdev = {
3453         .ndo_open            = virtnet_open,
3454         .ndo_stop            = virtnet_close,
3455         .ndo_start_xmit      = start_xmit,
3456         .ndo_validate_addr   = eth_validate_addr,
3457         .ndo_set_mac_address = virtnet_set_mac_address,
3458         .ndo_set_rx_mode     = virtnet_set_rx_mode,
3459         .ndo_get_stats64     = virtnet_stats,
3460         .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
3461         .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
3462         .ndo_bpf                = virtnet_xdp,
3463         .ndo_xdp_xmit           = virtnet_xdp_xmit,
3464         .ndo_features_check     = passthru_features_check,
3465         .ndo_get_phys_port_name = virtnet_get_phys_port_name,
3466         .ndo_set_features       = virtnet_set_features,
3467         .ndo_tx_timeout         = virtnet_tx_timeout,
3468 };
3469
3470 static void virtnet_config_changed_work(struct work_struct *work)
3471 {
3472         struct virtnet_info *vi =
3473                 container_of(work, struct virtnet_info, config_work);
3474         u16 v;
3475
3476         if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
3477                                  struct virtio_net_config, status, &v) < 0)
3478                 return;
3479
3480         if (v & VIRTIO_NET_S_ANNOUNCE) {
3481                 netdev_notify_peers(vi->dev);
3482                 virtnet_ack_link_announce(vi);
3483         }
3484
3485         /* Ignore unknown (future) status bits */
3486         v &= VIRTIO_NET_S_LINK_UP;
3487
3488         if (vi->status == v)
3489                 return;
3490
3491         vi->status = v;
3492
3493         if (vi->status & VIRTIO_NET_S_LINK_UP) {
3494                 virtnet_update_settings(vi);
3495                 netif_carrier_on(vi->dev);
3496                 netif_tx_wake_all_queues(vi->dev);
3497         } else {
3498                 netif_carrier_off(vi->dev);
3499                 netif_tx_stop_all_queues(vi->dev);
3500         }
3501 }
3502
3503 static void virtnet_config_changed(struct virtio_device *vdev)
3504 {
3505         struct virtnet_info *vi = vdev->priv;
3506
3507         schedule_work(&vi->config_work);
3508 }
3509
3510 static void virtnet_free_queues(struct virtnet_info *vi)
3511 {
3512         int i;
3513
3514         for (i = 0; i < vi->max_queue_pairs; i++) {
3515                 __netif_napi_del(&vi->rq[i].napi);
3516                 __netif_napi_del(&vi->sq[i].napi);
3517         }
3518
3519         /* We called __netif_napi_del(),
3520          * we need to respect an RCU grace period before freeing vi->rq
3521          */
3522         synchronize_net();
3523
3524         kfree(vi->rq);
3525         kfree(vi->sq);
3526         kfree(vi->ctrl);
3527 }
3528
3529 static void _free_receive_bufs(struct virtnet_info *vi)
3530 {
3531         struct bpf_prog *old_prog;
3532         int i;
3533
3534         for (i = 0; i < vi->max_queue_pairs; i++) {
3535                 while (vi->rq[i].pages)
3536                         __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
3537
3538                 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
3539                 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
3540                 if (old_prog)
3541                         bpf_prog_put(old_prog);
3542         }
3543 }
3544
3545 static void free_receive_bufs(struct virtnet_info *vi)
3546 {
3547         rtnl_lock();
3548         _free_receive_bufs(vi);
3549         rtnl_unlock();
3550 }
3551
3552 static void free_receive_page_frags(struct virtnet_info *vi)
3553 {
3554         int i;
3555         for (i = 0; i < vi->max_queue_pairs; i++)
3556                 if (vi->rq[i].alloc_frag.page)
3557                         put_page(vi->rq[i].alloc_frag.page);
3558 }
3559
3560 static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf)
3561 {
3562         if (!is_xdp_frame(buf))
3563                 dev_kfree_skb(buf);
3564         else
3565                 xdp_return_frame(ptr_to_xdp(buf));
3566 }
3567
3568 static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf)
3569 {
3570         struct virtnet_info *vi = vq->vdev->priv;
3571         int i = vq2rxq(vq);
3572
3573         if (vi->mergeable_rx_bufs)
3574                 put_page(virt_to_head_page(buf));
3575         else if (vi->big_packets)
3576                 give_pages(&vi->rq[i], buf);
3577         else
3578                 put_page(virt_to_head_page(buf));
3579 }
3580
3581 static void free_unused_bufs(struct virtnet_info *vi)
3582 {
3583         void *buf;
3584         int i;
3585
3586         for (i = 0; i < vi->max_queue_pairs; i++) {
3587                 struct virtqueue *vq = vi->sq[i].vq;
3588                 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
3589                         virtnet_sq_free_unused_buf(vq, buf);
3590                 cond_resched();
3591         }
3592
3593         for (i = 0; i < vi->max_queue_pairs; i++) {
3594                 struct virtqueue *vq = vi->rq[i].vq;
3595                 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
3596                         virtnet_rq_free_unused_buf(vq, buf);
3597                 cond_resched();
3598         }
3599 }
3600
3601 static void virtnet_del_vqs(struct virtnet_info *vi)
3602 {
3603         struct virtio_device *vdev = vi->vdev;
3604
3605         virtnet_clean_affinity(vi);
3606
3607         vdev->config->del_vqs(vdev);
3608
3609         virtnet_free_queues(vi);
3610 }
3611
3612 /* How large should a single buffer be so a queue full of these can fit at
3613  * least one full packet?
3614  * Logic below assumes the mergeable buffer header is used.
3615  */
3616 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
3617 {
3618         const unsigned int hdr_len = vi->hdr_len;
3619         unsigned int rq_size = virtqueue_get_vring_size(vq);
3620         unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
3621         unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
3622         unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
3623
3624         return max(max(min_buf_len, hdr_len) - hdr_len,
3625                    (unsigned int)GOOD_PACKET_LEN);
3626 }
3627
3628 static int virtnet_find_vqs(struct virtnet_info *vi)
3629 {
3630         vq_callback_t **callbacks;
3631         struct virtqueue **vqs;
3632         int ret = -ENOMEM;
3633         int i, total_vqs;
3634         const char **names;
3635         bool *ctx;
3636
3637         /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
3638          * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
3639          * possible control vq.
3640          */
3641         total_vqs = vi->max_queue_pairs * 2 +
3642                     virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
3643
3644         /* Allocate space for find_vqs parameters */
3645         vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL);
3646         if (!vqs)
3647                 goto err_vq;
3648         callbacks = kmalloc_array(total_vqs, sizeof(*callbacks), GFP_KERNEL);
3649         if (!callbacks)
3650                 goto err_callback;
3651         names = kmalloc_array(total_vqs, sizeof(*names), GFP_KERNEL);
3652         if (!names)
3653                 goto err_names;
3654         if (!vi->big_packets || vi->mergeable_rx_bufs) {
3655                 ctx = kcalloc(total_vqs, sizeof(*ctx), GFP_KERNEL);
3656                 if (!ctx)
3657                         goto err_ctx;
3658         } else {
3659                 ctx = NULL;
3660         }
3661
3662         /* Parameters for control virtqueue, if any */
3663         if (vi->has_cvq) {
3664                 callbacks[total_vqs - 1] = NULL;
3665                 names[total_vqs - 1] = "control";
3666         }
3667
3668         /* Allocate/initialize parameters for send/receive virtqueues */
3669         for (i = 0; i < vi->max_queue_pairs; i++) {
3670                 callbacks[rxq2vq(i)] = skb_recv_done;
3671                 callbacks[txq2vq(i)] = skb_xmit_done;
3672                 sprintf(vi->rq[i].name, "input.%d", i);
3673                 sprintf(vi->sq[i].name, "output.%d", i);
3674                 names[rxq2vq(i)] = vi->rq[i].name;
3675                 names[txq2vq(i)] = vi->sq[i].name;
3676                 if (ctx)
3677                         ctx[rxq2vq(i)] = true;
3678         }
3679
3680         ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks,
3681                                   names, ctx, NULL);
3682         if (ret)
3683                 goto err_find;
3684
3685         if (vi->has_cvq) {
3686                 vi->cvq = vqs[total_vqs - 1];
3687                 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
3688                         vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
3689         }
3690
3691         for (i = 0; i < vi->max_queue_pairs; i++) {
3692                 vi->rq[i].vq = vqs[rxq2vq(i)];
3693                 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
3694                 vi->sq[i].vq = vqs[txq2vq(i)];
3695         }
3696
3697         /* run here: ret == 0. */
3698
3699
3700 err_find:
3701         kfree(ctx);
3702 err_ctx:
3703         kfree(names);
3704 err_names:
3705         kfree(callbacks);
3706 err_callback:
3707         kfree(vqs);
3708 err_vq:
3709         return ret;
3710 }
3711
3712 static int virtnet_alloc_queues(struct virtnet_info *vi)
3713 {
3714         int i;
3715
3716         if (vi->has_cvq) {
3717                 vi->ctrl = kzalloc(sizeof(*vi->ctrl), GFP_KERNEL);
3718                 if (!vi->ctrl)
3719                         goto err_ctrl;
3720         } else {
3721                 vi->ctrl = NULL;
3722         }
3723         vi->sq = kcalloc(vi->max_queue_pairs, sizeof(*vi->sq), GFP_KERNEL);
3724         if (!vi->sq)
3725                 goto err_sq;
3726         vi->rq = kcalloc(vi->max_queue_pairs, sizeof(*vi->rq), GFP_KERNEL);
3727         if (!vi->rq)
3728                 goto err_rq;
3729
3730         INIT_DELAYED_WORK(&vi->refill, refill_work);
3731         for (i = 0; i < vi->max_queue_pairs; i++) {
3732                 vi->rq[i].pages = NULL;
3733                 netif_napi_add_weight(vi->dev, &vi->rq[i].napi, virtnet_poll,
3734                                       napi_weight);
3735                 netif_napi_add_tx_weight(vi->dev, &vi->sq[i].napi,
3736                                          virtnet_poll_tx,
3737                                          napi_tx ? napi_weight : 0);
3738
3739                 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
3740                 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
3741                 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
3742
3743                 u64_stats_init(&vi->rq[i].stats.syncp);
3744                 u64_stats_init(&vi->sq[i].stats.syncp);
3745         }
3746
3747         return 0;
3748
3749 err_rq:
3750         kfree(vi->sq);
3751 err_sq:
3752         kfree(vi->ctrl);
3753 err_ctrl:
3754         return -ENOMEM;
3755 }
3756
3757 static int init_vqs(struct virtnet_info *vi)
3758 {
3759         int ret;
3760
3761         /* Allocate send & receive queues */
3762         ret = virtnet_alloc_queues(vi);
3763         if (ret)
3764                 goto err;
3765
3766         ret = virtnet_find_vqs(vi);
3767         if (ret)
3768                 goto err_free;
3769
3770         cpus_read_lock();
3771         virtnet_set_affinity(vi);
3772         cpus_read_unlock();
3773
3774         return 0;
3775
3776 err_free:
3777         virtnet_free_queues(vi);
3778 err:
3779         return ret;
3780 }
3781
3782 #ifdef CONFIG_SYSFS
3783 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
3784                 char *buf)
3785 {
3786         struct virtnet_info *vi = netdev_priv(queue->dev);
3787         unsigned int queue_index = get_netdev_rx_queue_index(queue);
3788         unsigned int headroom = virtnet_get_headroom(vi);
3789         unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
3790         struct ewma_pkt_len *avg;
3791
3792         BUG_ON(queue_index >= vi->max_queue_pairs);
3793         avg = &vi->rq[queue_index].mrg_avg_pkt_len;
3794         return sprintf(buf, "%u\n",
3795                        get_mergeable_buf_len(&vi->rq[queue_index], avg,
3796                                        SKB_DATA_ALIGN(headroom + tailroom)));
3797 }
3798
3799 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
3800         __ATTR_RO(mergeable_rx_buffer_size);
3801
3802 static struct attribute *virtio_net_mrg_rx_attrs[] = {
3803         &mergeable_rx_buffer_size_attribute.attr,
3804         NULL
3805 };
3806
3807 static const struct attribute_group virtio_net_mrg_rx_group = {
3808         .name = "virtio_net",
3809         .attrs = virtio_net_mrg_rx_attrs
3810 };
3811 #endif
3812
3813 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
3814                                     unsigned int fbit,
3815                                     const char *fname, const char *dname)
3816 {
3817         if (!virtio_has_feature(vdev, fbit))
3818                 return false;
3819
3820         dev_err(&vdev->dev, "device advertises feature %s but not %s",
3821                 fname, dname);
3822
3823         return true;
3824 }
3825
3826 #define VIRTNET_FAIL_ON(vdev, fbit, dbit)                       \
3827         virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
3828
3829 static bool virtnet_validate_features(struct virtio_device *vdev)
3830 {
3831         if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
3832             (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
3833                              "VIRTIO_NET_F_CTRL_VQ") ||
3834              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
3835                              "VIRTIO_NET_F_CTRL_VQ") ||
3836              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
3837                              "VIRTIO_NET_F_CTRL_VQ") ||
3838              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
3839              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
3840                              "VIRTIO_NET_F_CTRL_VQ") ||
3841              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS,
3842                              "VIRTIO_NET_F_CTRL_VQ") ||
3843              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
3844                              "VIRTIO_NET_F_CTRL_VQ") ||
3845              VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_NOTF_COAL,
3846                              "VIRTIO_NET_F_CTRL_VQ"))) {
3847                 return false;
3848         }
3849
3850         return true;
3851 }
3852
3853 #define MIN_MTU ETH_MIN_MTU
3854 #define MAX_MTU ETH_MAX_MTU
3855
3856 static int virtnet_validate(struct virtio_device *vdev)
3857 {
3858         if (!vdev->config->get) {
3859                 dev_err(&vdev->dev, "%s failure: config access disabled\n",
3860                         __func__);
3861                 return -EINVAL;
3862         }
3863
3864         if (!virtnet_validate_features(vdev))
3865                 return -EINVAL;
3866
3867         if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
3868                 int mtu = virtio_cread16(vdev,
3869                                          offsetof(struct virtio_net_config,
3870                                                   mtu));
3871                 if (mtu < MIN_MTU)
3872                         __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
3873         }
3874
3875         if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY) &&
3876             !virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
3877                 dev_warn(&vdev->dev, "device advertises feature VIRTIO_NET_F_STANDBY but not VIRTIO_NET_F_MAC, disabling standby");
3878                 __virtio_clear_bit(vdev, VIRTIO_NET_F_STANDBY);
3879         }
3880
3881         return 0;
3882 }
3883
3884 static bool virtnet_check_guest_gso(const struct virtnet_info *vi)
3885 {
3886         return virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3887                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
3888                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
3889                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) ||
3890                 (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO4) &&
3891                 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO6));
3892 }
3893
3894 static void virtnet_set_big_packets(struct virtnet_info *vi, const int mtu)
3895 {
3896         bool guest_gso = virtnet_check_guest_gso(vi);
3897
3898         /* If device can receive ANY guest GSO packets, regardless of mtu,
3899          * allocate packets of maximum size, otherwise limit it to only
3900          * mtu size worth only.
3901          */
3902         if (mtu > ETH_DATA_LEN || guest_gso) {
3903                 vi->big_packets = true;
3904                 vi->big_packets_num_skbfrags = guest_gso ? MAX_SKB_FRAGS : DIV_ROUND_UP(mtu, PAGE_SIZE);
3905         }
3906 }
3907
3908 static int virtnet_probe(struct virtio_device *vdev)
3909 {
3910         int i, err = -ENOMEM;
3911         struct net_device *dev;
3912         struct virtnet_info *vi;
3913         u16 max_queue_pairs;
3914         int mtu = 0;
3915
3916         /* Find if host supports multiqueue/rss virtio_net device */
3917         max_queue_pairs = 1;
3918         if (virtio_has_feature(vdev, VIRTIO_NET_F_MQ) || virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
3919                 max_queue_pairs =
3920                      virtio_cread16(vdev, offsetof(struct virtio_net_config, max_virtqueue_pairs));
3921
3922         /* We need at least 2 queue's */
3923         if (max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
3924             max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
3925             !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
3926                 max_queue_pairs = 1;
3927
3928         /* Allocate ourselves a network device with room for our info */
3929         dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
3930         if (!dev)
3931                 return -ENOMEM;
3932
3933         /* Set up network device as normal. */
3934         dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE |
3935                            IFF_TX_SKB_NO_LINEAR;
3936         dev->netdev_ops = &virtnet_netdev;
3937         dev->features = NETIF_F_HIGHDMA;
3938
3939         dev->ethtool_ops = &virtnet_ethtool_ops;
3940         SET_NETDEV_DEV(dev, &vdev->dev);
3941
3942         /* Do we support "hardware" checksums? */
3943         if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
3944                 /* This opens up the world of extra features. */
3945                 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
3946                 if (csum)
3947                         dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
3948
3949                 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
3950                         dev->hw_features |= NETIF_F_TSO
3951                                 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
3952                 }
3953                 /* Individual feature bits: what can host handle? */
3954                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
3955                         dev->hw_features |= NETIF_F_TSO;
3956                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
3957                         dev->hw_features |= NETIF_F_TSO6;
3958                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
3959                         dev->hw_features |= NETIF_F_TSO_ECN;
3960                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_USO))
3961                         dev->hw_features |= NETIF_F_GSO_UDP_L4;
3962
3963                 dev->features |= NETIF_F_GSO_ROBUST;
3964
3965                 if (gso)
3966                         dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
3967                 /* (!csum && gso) case will be fixed by register_netdev() */
3968         }
3969         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
3970                 dev->features |= NETIF_F_RXCSUM;
3971         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3972             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6))
3973                 dev->features |= NETIF_F_GRO_HW;
3974         if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS))
3975                 dev->hw_features |= NETIF_F_GRO_HW;
3976
3977         dev->vlan_features = dev->features;
3978         dev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT;
3979
3980         /* MTU range: 68 - 65535 */
3981         dev->min_mtu = MIN_MTU;
3982         dev->max_mtu = MAX_MTU;
3983
3984         /* Configuration may specify what MAC to use.  Otherwise random. */
3985         if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
3986                 u8 addr[ETH_ALEN];
3987
3988                 virtio_cread_bytes(vdev,
3989                                    offsetof(struct virtio_net_config, mac),
3990                                    addr, ETH_ALEN);
3991                 eth_hw_addr_set(dev, addr);
3992         } else {
3993                 eth_hw_addr_random(dev);
3994                 dev_info(&vdev->dev, "Assigned random MAC address %pM\n",
3995                          dev->dev_addr);
3996         }
3997
3998         /* Set up our device-specific information */
3999         vi = netdev_priv(dev);
4000         vi->dev = dev;
4001         vi->vdev = vdev;
4002         vdev->priv = vi;
4003
4004         INIT_WORK(&vi->config_work, virtnet_config_changed_work);
4005         spin_lock_init(&vi->refill_lock);
4006
4007         if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) {
4008                 vi->mergeable_rx_bufs = true;
4009                 dev->xdp_features |= NETDEV_XDP_ACT_RX_SG;
4010         }
4011
4012         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) {
4013                 vi->rx_usecs = 0;
4014                 vi->tx_usecs = 0;
4015                 vi->tx_max_packets = 0;
4016                 vi->rx_max_packets = 0;
4017         }
4018
4019         if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT))
4020                 vi->has_rss_hash_report = true;
4021
4022         if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
4023                 vi->has_rss = true;
4024
4025         if (vi->has_rss || vi->has_rss_hash_report) {
4026                 vi->rss_indir_table_size =
4027                         virtio_cread16(vdev, offsetof(struct virtio_net_config,
4028                                 rss_max_indirection_table_length));
4029                 vi->rss_key_size =
4030                         virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
4031
4032                 vi->rss_hash_types_supported =
4033                     virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
4034                 vi->rss_hash_types_supported &=
4035                                 ~(VIRTIO_NET_RSS_HASH_TYPE_IP_EX |
4036                                   VIRTIO_NET_RSS_HASH_TYPE_TCP_EX |
4037                                   VIRTIO_NET_RSS_HASH_TYPE_UDP_EX);
4038
4039                 dev->hw_features |= NETIF_F_RXHASH;
4040         }
4041
4042         if (vi->has_rss_hash_report)
4043                 vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);
4044         else if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
4045                  virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
4046                 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
4047         else
4048                 vi->hdr_len = sizeof(struct virtio_net_hdr);
4049
4050         if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
4051             virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
4052                 vi->any_header_sg = true;
4053
4054         if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
4055                 vi->has_cvq = true;
4056
4057         if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
4058                 mtu = virtio_cread16(vdev,
4059                                      offsetof(struct virtio_net_config,
4060                                               mtu));
4061                 if (mtu < dev->min_mtu) {
4062                         /* Should never trigger: MTU was previously validated
4063                          * in virtnet_validate.
4064                          */
4065                         dev_err(&vdev->dev,
4066                                 "device MTU appears to have changed it is now %d < %d",
4067                                 mtu, dev->min_mtu);
4068                         err = -EINVAL;
4069                         goto free;
4070                 }
4071
4072                 dev->mtu = mtu;
4073                 dev->max_mtu = mtu;
4074         }
4075
4076         virtnet_set_big_packets(vi, mtu);
4077
4078         if (vi->any_header_sg)
4079                 dev->needed_headroom = vi->hdr_len;
4080
4081         /* Enable multiqueue by default */
4082         if (num_online_cpus() >= max_queue_pairs)
4083                 vi->curr_queue_pairs = max_queue_pairs;
4084         else
4085                 vi->curr_queue_pairs = num_online_cpus();
4086         vi->max_queue_pairs = max_queue_pairs;
4087
4088         /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
4089         err = init_vqs(vi);
4090         if (err)
4091                 goto free;
4092
4093 #ifdef CONFIG_SYSFS
4094         if (vi->mergeable_rx_bufs)
4095                 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
4096 #endif
4097         netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
4098         netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
4099
4100         virtnet_init_settings(dev);
4101
4102         if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
4103                 vi->failover = net_failover_create(vi->dev);
4104                 if (IS_ERR(vi->failover)) {
4105                         err = PTR_ERR(vi->failover);
4106                         goto free_vqs;
4107                 }
4108         }
4109
4110         if (vi->has_rss || vi->has_rss_hash_report)
4111                 virtnet_init_default_rss(vi);
4112
4113         /* serialize netdev register + virtio_device_ready() with ndo_open() */
4114         rtnl_lock();
4115
4116         err = register_netdevice(dev);
4117         if (err) {
4118                 pr_debug("virtio_net: registering device failed\n");
4119                 rtnl_unlock();
4120                 goto free_failover;
4121         }
4122
4123         virtio_device_ready(vdev);
4124
4125         /* a random MAC address has been assigned, notify the device.
4126          * We don't fail probe if VIRTIO_NET_F_CTRL_MAC_ADDR is not there
4127          * because many devices work fine without getting MAC explicitly
4128          */
4129         if (!virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
4130             virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
4131                 struct scatterlist sg;
4132
4133                 sg_init_one(&sg, dev->dev_addr, dev->addr_len);
4134                 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
4135                                           VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
4136                         pr_debug("virtio_net: setting MAC address failed\n");
4137                         rtnl_unlock();
4138                         err = -EINVAL;
4139                         goto free_unregister_netdev;
4140                 }
4141         }
4142
4143         rtnl_unlock();
4144
4145         err = virtnet_cpu_notif_add(vi);
4146         if (err) {
4147                 pr_debug("virtio_net: registering cpu notifier failed\n");
4148                 goto free_unregister_netdev;
4149         }
4150
4151         virtnet_set_queues(vi, vi->curr_queue_pairs);
4152
4153         /* Assume link up if device can't report link status,
4154            otherwise get link status from config. */
4155         netif_carrier_off(dev);
4156         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
4157                 schedule_work(&vi->config_work);
4158         } else {
4159                 vi->status = VIRTIO_NET_S_LINK_UP;
4160                 virtnet_update_settings(vi);
4161                 netif_carrier_on(dev);
4162         }
4163
4164         for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
4165                 if (virtio_has_feature(vi->vdev, guest_offloads[i]))
4166                         set_bit(guest_offloads[i], &vi->guest_offloads);
4167         vi->guest_offloads_capable = vi->guest_offloads;
4168
4169         pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
4170                  dev->name, max_queue_pairs);
4171
4172         return 0;
4173
4174 free_unregister_netdev:
4175         unregister_netdev(dev);
4176 free_failover:
4177         net_failover_destroy(vi->failover);
4178 free_vqs:
4179         virtio_reset_device(vdev);
4180         cancel_delayed_work_sync(&vi->refill);
4181         free_receive_page_frags(vi);
4182         virtnet_del_vqs(vi);
4183 free:
4184         free_netdev(dev);
4185         return err;
4186 }
4187
4188 static void remove_vq_common(struct virtnet_info *vi)
4189 {
4190         virtio_reset_device(vi->vdev);
4191
4192         /* Free unused buffers in both send and recv, if any. */
4193         free_unused_bufs(vi);
4194
4195         free_receive_bufs(vi);
4196
4197         free_receive_page_frags(vi);
4198
4199         virtnet_del_vqs(vi);
4200 }
4201
4202 static void virtnet_remove(struct virtio_device *vdev)
4203 {
4204         struct virtnet_info *vi = vdev->priv;
4205
4206         virtnet_cpu_notif_remove(vi);
4207
4208         /* Make sure no work handler is accessing the device. */
4209         flush_work(&vi->config_work);
4210
4211         unregister_netdev(vi->dev);
4212
4213         net_failover_destroy(vi->failover);
4214
4215         remove_vq_common(vi);
4216
4217         free_netdev(vi->dev);
4218 }
4219
4220 static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
4221 {
4222         struct virtnet_info *vi = vdev->priv;
4223
4224         virtnet_cpu_notif_remove(vi);
4225         virtnet_freeze_down(vdev);
4226         remove_vq_common(vi);
4227
4228         return 0;
4229 }
4230
4231 static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
4232 {
4233         struct virtnet_info *vi = vdev->priv;
4234         int err;
4235
4236         err = virtnet_restore_up(vdev);
4237         if (err)
4238                 return err;
4239         virtnet_set_queues(vi, vi->curr_queue_pairs);
4240
4241         err = virtnet_cpu_notif_add(vi);
4242         if (err) {
4243                 virtnet_freeze_down(vdev);
4244                 remove_vq_common(vi);
4245                 return err;
4246         }
4247
4248         return 0;
4249 }
4250
4251 static struct virtio_device_id id_table[] = {
4252         { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
4253         { 0 },
4254 };
4255
4256 #define VIRTNET_FEATURES \
4257         VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
4258         VIRTIO_NET_F_MAC, \
4259         VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
4260         VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
4261         VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
4262         VIRTIO_NET_F_HOST_USO, VIRTIO_NET_F_GUEST_USO4, VIRTIO_NET_F_GUEST_USO6, \
4263         VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
4264         VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
4265         VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
4266         VIRTIO_NET_F_CTRL_MAC_ADDR, \
4267         VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
4268         VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
4269         VIRTIO_NET_F_RSS, VIRTIO_NET_F_HASH_REPORT, VIRTIO_NET_F_NOTF_COAL, \
4270         VIRTIO_NET_F_GUEST_HDRLEN
4271
4272 static unsigned int features[] = {
4273         VIRTNET_FEATURES,
4274 };
4275
4276 static unsigned int features_legacy[] = {
4277         VIRTNET_FEATURES,
4278         VIRTIO_NET_F_GSO,
4279         VIRTIO_F_ANY_LAYOUT,
4280 };
4281
4282 static struct virtio_driver virtio_net_driver = {
4283         .feature_table = features,
4284         .feature_table_size = ARRAY_SIZE(features),
4285         .feature_table_legacy = features_legacy,
4286         .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
4287         .driver.name =  KBUILD_MODNAME,
4288         .driver.owner = THIS_MODULE,
4289         .id_table =     id_table,
4290         .validate =     virtnet_validate,
4291         .probe =        virtnet_probe,
4292         .remove =       virtnet_remove,
4293         .config_changed = virtnet_config_changed,
4294 #ifdef CONFIG_PM_SLEEP
4295         .freeze =       virtnet_freeze,
4296         .restore =      virtnet_restore,
4297 #endif
4298 };
4299
4300 static __init int virtio_net_driver_init(void)
4301 {
4302         int ret;
4303
4304         ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
4305                                       virtnet_cpu_online,
4306                                       virtnet_cpu_down_prep);
4307         if (ret < 0)
4308                 goto out;
4309         virtionet_online = ret;
4310         ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
4311                                       NULL, virtnet_cpu_dead);
4312         if (ret)
4313                 goto err_dead;
4314         ret = register_virtio_driver(&virtio_net_driver);
4315         if (ret)
4316                 goto err_virtio;
4317         return 0;
4318 err_virtio:
4319         cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
4320 err_dead:
4321         cpuhp_remove_multi_state(virtionet_online);
4322 out:
4323         return ret;
4324 }
4325 module_init(virtio_net_driver_init);
4326
4327 static __exit void virtio_net_driver_exit(void)
4328 {
4329         unregister_virtio_driver(&virtio_net_driver);
4330         cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
4331         cpuhp_remove_multi_state(virtionet_online);
4332 }
4333 module_exit(virtio_net_driver_exit);
4334
4335 MODULE_DEVICE_TABLE(virtio, id_table);
4336 MODULE_DESCRIPTION("Virtio network driver");
4337 MODULE_LICENSE("GPL");