drivers/net/hyperv/netvsc_drv.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2009, Microsoft Corporation.
   4  *
   5  * Authors:
   6  *   Haiyang Zhang <haiyangz@microsoft.com>
   7  *   Hank Janssen  <hjanssen@microsoft.com>
   8  */
   9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  10
  11 #include <linux/init.h>
  12 #include <linux/atomic.h>
  13 #include <linux/module.h>
  14 #include <linux/highmem.h>
  15 #include <linux/device.h>
  16 #include <linux/io.h>
  17 #include <linux/delay.h>
  18 #include <linux/netdevice.h>
  19 #include <linux/inetdevice.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/pci.h>
  22 #include <linux/skbuff.h>
  23 #include <linux/if_vlan.h>
  24 #include <linux/in.h>
  25 #include <linux/slab.h>
  26 #include <linux/rtnetlink.h>
  27 #include <linux/netpoll.h>
  28
  29 #include <net/arp.h>
  30 #include <net/route.h>
  31 #include <net/sock.h>
  32 #include <net/pkt_sched.h>
  33 #include <net/checksum.h>
  34 #include <net/ip6_checksum.h>
  35
  36 #include "hyperv_net.h"
  37
  38 #define RING_SIZE_MIN   64
  39 #define RETRY_US_LO     5000
  40 #define RETRY_US_HI     10000
  41 #define RETRY_MAX       2000    /* >10 sec */
  42
  43 #define LINKCHANGE_INT (2 * HZ)
  44 #define VF_TAKEOVER_INT (HZ / 10)
  45
  46 static unsigned int ring_size __ro_after_init = 128;
  47 module_param(ring_size, uint, 0444);
  48 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
  49 unsigned int netvsc_ring_bytes __ro_after_init;
  50
  51 static const u32 default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
  52                                 NETIF_MSG_LINK | NETIF_MSG_IFUP |
  53                                 NETIF_MSG_IFDOWN | NETIF_MSG_RX_ERR |
  54                                 NETIF_MSG_TX_ERR;
  55
  56 static int debug = -1;
  57 module_param(debug, int, 0444);
  58 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
  59
  60 static LIST_HEAD(netvsc_dev_list);
  61
  62 static void netvsc_change_rx_flags(struct net_device *net, int change)
  63 {
  64         struct net_device_context *ndev_ctx = netdev_priv(net);
  65         struct net_device *vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
  66         int inc;
  67
  68         if (!vf_netdev)
  69                 return;
  70
  71         if (change & IFF_PROMISC) {
  72                 inc = (net->flags & IFF_PROMISC) ? 1 : -1;
  73                 dev_set_promiscuity(vf_netdev, inc);
  74         }
  75
  76         if (change & IFF_ALLMULTI) {
  77                 inc = (net->flags & IFF_ALLMULTI) ? 1 : -1;
  78                 dev_set_allmulti(vf_netdev, inc);
  79         }
  80 }
  81
  82 static void netvsc_set_rx_mode(struct net_device *net)
  83 {
  84         struct net_device_context *ndev_ctx = netdev_priv(net);
  85         struct net_device *vf_netdev;
  86         struct netvsc_device *nvdev;
  87
  88         rcu_read_lock();
  89         vf_netdev = rcu_dereference(ndev_ctx->vf_netdev);
  90         if (vf_netdev) {
  91                 dev_uc_sync(vf_netdev, net);
  92                 dev_mc_sync(vf_netdev, net);
  93         }
  94
  95         nvdev = rcu_dereference(ndev_ctx->nvdev);
  96         if (nvdev)
  97                 rndis_filter_update(nvdev);
  98         rcu_read_unlock();
  99 }
 100
 101 static void netvsc_tx_enable(struct netvsc_device *nvscdev,
 102                              struct net_device *ndev)
 103 {
 104         nvscdev->tx_disable = false;
 105         virt_wmb(); /* ensure queue wake up mechanism is on */
 106
 107         netif_tx_wake_all_queues(ndev);
 108 }
 109
 110 static int netvsc_open(struct net_device *net)
 111 {
 112         struct net_device_context *ndev_ctx = netdev_priv(net);
 113         struct net_device *vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
 114         struct netvsc_device *nvdev = rtnl_dereference(ndev_ctx->nvdev);
 115         struct rndis_device *rdev;
 116         int ret = 0;
 117
 118         netif_carrier_off(net);
 119
 120         /* Open up the device */
 121         ret = rndis_filter_open(nvdev);
 122         if (ret != 0) {
 123                 netdev_err(net, "unable to open device (ret %d).\n", ret);
 124                 return ret;
 125         }
 126
 127         rdev = nvdev->extension;
 128         if (!rdev->link_state) {
 129                 netif_carrier_on(net);
 130                 netvsc_tx_enable(nvdev, net);
 131         }
 132
 133         if (vf_netdev) {
 134                 /* Setting synthetic device up transparently sets
 135                  * slave as up. If open fails, then slave will be
 136                  * still be offline (and not used).
 137                  */
 138                 ret = dev_open(vf_netdev, NULL);
 139                 if (ret)
 140                         netdev_warn(net,
 141                                     "unable to open slave: %s: %d\n",
 142                                     vf_netdev->name, ret);
 143         }
 144         return 0;
 145 }
 146
 147 static int netvsc_wait_until_empty(struct netvsc_device *nvdev)
 148 {
 149         unsigned int retry = 0;
 150         int i;
 151
 152         /* Ensure pending bytes in ring are read */
 153         for (;;) {
 154                 u32 aread = 0;
 155
 156                 for (i = 0; i < nvdev->num_chn; i++) {
 157                         struct vmbus_channel *chn
 158                                 = nvdev->chan_table[i].channel;
 159
 160                         if (!chn)
 161                                 continue;
 162
 163                         /* make sure receive not running now */
 164                         napi_synchronize(&nvdev->chan_table[i].napi);
 165
 166                         aread = hv_get_bytes_to_read(&chn->inbound);
 167                         if (aread)
 168                                 break;
 169
 170                         aread = hv_get_bytes_to_read(&chn->outbound);
 171                         if (aread)
 172                                 break;
 173                 }
 174
 175                 if (aread == 0)
 176                         return 0;
 177
 178                 if (++retry > RETRY_MAX)
 179                         return -ETIMEDOUT;
 180
 181                 usleep_range(RETRY_US_LO, RETRY_US_HI);
 182         }
 183 }
 184
 185 static void netvsc_tx_disable(struct netvsc_device *nvscdev,
 186                               struct net_device *ndev)
 187 {
 188         if (nvscdev) {
 189                 nvscdev->tx_disable = true;
 190                 virt_wmb(); /* ensure txq will not wake up after stop */
 191         }
 192
 193         netif_tx_disable(ndev);
 194 }
 195
 196 static int netvsc_close(struct net_device *net)
 197 {
 198         struct net_device_context *net_device_ctx = netdev_priv(net);
 199         struct net_device *vf_netdev
 200                 = rtnl_dereference(net_device_ctx->vf_netdev);
 201         struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 202         int ret;
 203
 204         netvsc_tx_disable(nvdev, net);
 205
 206         /* No need to close rndis filter if it is removed already */
 207         if (!nvdev)
 208                 return 0;
 209
 210         ret = rndis_filter_close(nvdev);
 211         if (ret != 0) {
 212                 netdev_err(net, "unable to close device (ret %d).\n", ret);
 213                 return ret;
 214         }
 215
 216         ret = netvsc_wait_until_empty(nvdev);
 217         if (ret)
 218                 netdev_err(net, "Ring buffer not empty after closing rndis\n");
 219
 220         if (vf_netdev)
 221                 dev_close(vf_netdev);
 222
 223         return ret;
 224 }
 225
 226 static inline void *init_ppi_data(struct rndis_message *msg,
 227                                   u32 ppi_size, u32 pkt_type)
 228 {
 229         struct rndis_packet *rndis_pkt = &msg->msg.pkt;
 230         struct rndis_per_packet_info *ppi;
 231
 232         rndis_pkt->data_offset += ppi_size;
 233         ppi = (void *)rndis_pkt + rndis_pkt->per_pkt_info_offset
 234                 + rndis_pkt->per_pkt_info_len;
 235
 236         ppi->size = ppi_size;
 237         ppi->type = pkt_type;
 238         ppi->internal = 0;
 239         ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
 240
 241         rndis_pkt->per_pkt_info_len += ppi_size;
 242
 243         return ppi + 1;
 244 }
 245
 246 /* Azure hosts don't support non-TCP port numbers in hashing for fragmented
 247  * packets. We can use ethtool to change UDP hash level when necessary.
 248  */
 249 static inline u32 netvsc_get_hash(
 250         struct sk_buff *skb,
 251         const struct net_device_context *ndc)
 252 {
 253         struct flow_keys flow;
 254         u32 hash, pkt_proto = 0;
 255         static u32 hashrnd __read_mostly;
 256
 257         net_get_random_once(&hashrnd, sizeof(hashrnd));
 258
 259         if (!skb_flow_dissect_flow_keys(skb, &flow, 0))
 260                 return 0;
 261
 262         switch (flow.basic.ip_proto) {
 263         case IPPROTO_TCP:
 264                 if (flow.basic.n_proto == htons(ETH_P_IP))
 265                         pkt_proto = HV_TCP4_L4HASH;
 266                 else if (flow.basic.n_proto == htons(ETH_P_IPV6))
 267                         pkt_proto = HV_TCP6_L4HASH;
 268
 269                 break;
 270
 271         case IPPROTO_UDP:
 272                 if (flow.basic.n_proto == htons(ETH_P_IP))
 273                         pkt_proto = HV_UDP4_L4HASH;
 274                 else if (flow.basic.n_proto == htons(ETH_P_IPV6))
 275                         pkt_proto = HV_UDP6_L4HASH;
 276
 277                 break;
 278         }
 279
 280         if (pkt_proto & ndc->l4_hash) {
 281                 return skb_get_hash(skb);
 282         } else {
 283                 if (flow.basic.n_proto == htons(ETH_P_IP))
 284                         hash = jhash2((u32 *)&flow.addrs.v4addrs, 2, hashrnd);
 285                 else if (flow.basic.n_proto == htons(ETH_P_IPV6))
 286                         hash = jhash2((u32 *)&flow.addrs.v6addrs, 8, hashrnd);
 287                 else
 288                         hash = 0;
 289
 290                 skb_set_hash(skb, hash, PKT_HASH_TYPE_L3);
 291         }
 292
 293         return hash;
 294 }
 295
 296 static inline int netvsc_get_tx_queue(struct net_device *ndev,
 297                                       struct sk_buff *skb, int old_idx)
 298 {
 299         const struct net_device_context *ndc = netdev_priv(ndev);
 300         struct sock *sk = skb->sk;
 301         int q_idx;
 302
 303         q_idx = ndc->tx_table[netvsc_get_hash(skb, ndc) &
 304                               (VRSS_SEND_TAB_SIZE - 1)];
 305
 306         /* If queue index changed record the new value */
 307         if (q_idx != old_idx &&
 308             sk && sk_fullsock(sk) && rcu_access_pointer(sk->sk_dst_cache))
 309                 sk_tx_queue_set(sk, q_idx);
 310
 311         return q_idx;
 312 }
 313
 314 /*
 315  * Select queue for transmit.
 316  *
 317  * If a valid queue has already been assigned, then use that.
 318  * Otherwise compute tx queue based on hash and the send table.
 319  *
 320  * This is basically similar to default (netdev_pick_tx) with the added step
 321  * of using the host send_table when no other queue has been assigned.
 322  *
 323  * TODO support XPS - but get_xps_queue not exported
 324  */
 325 static u16 netvsc_pick_tx(struct net_device *ndev, struct sk_buff *skb)
 326 {
 327         int q_idx = sk_tx_queue_get(skb->sk);
 328
 329         if (q_idx < 0 || skb->ooo_okay || q_idx >= ndev->real_num_tx_queues) {
 330                 /* If forwarding a packet, we use the recorded queue when
 331                  * available for better cache locality.
 332                  */
 333                 if (skb_rx_queue_recorded(skb))
 334                         q_idx = skb_get_rx_queue(skb);
 335                 else
 336                         q_idx = netvsc_get_tx_queue(ndev, skb, q_idx);
 337         }
 338
 339         return q_idx;
 340 }
 341
 342 static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
 343                                struct net_device *sb_dev)
 344 {
 345         struct net_device_context *ndc = netdev_priv(ndev);
 346         struct net_device *vf_netdev;
 347         u16 txq;
 348
 349         rcu_read_lock();
 350         vf_netdev = rcu_dereference(ndc->vf_netdev);
 351         if (vf_netdev) {
 352                 const struct net_device_ops *vf_ops = vf_netdev->netdev_ops;
 353
 354                 if (vf_ops->ndo_select_queue)
 355                         txq = vf_ops->ndo_select_queue(vf_netdev, skb, sb_dev);
 356                 else
 357                         txq = netdev_pick_tx(vf_netdev, skb, NULL);
 358
 359                 /* Record the queue selected by VF so that it can be
 360                  * used for common case where VF has more queues than
 361                  * the synthetic device.
 362                  */
 363                 qdisc_skb_cb(skb)->slave_dev_queue_mapping = txq;
 364         } else {
 365                 txq = netvsc_pick_tx(ndev, skb);
 366         }
 367         rcu_read_unlock();
 368
 369         while (unlikely(txq >= ndev->real_num_tx_queues))
 370                 txq -= ndev->real_num_tx_queues;
 371
 372         return txq;
 373 }
 374
 375 static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
 376                        struct hv_page_buffer *pb)
 377 {
 378         int j = 0;
 379
 380         /* Deal with compound pages by ignoring unused part
 381          * of the page.
 382          */
 383         page += (offset >> PAGE_SHIFT);
 384         offset &= ~PAGE_MASK;
 385
 386         while (len > 0) {
 387                 unsigned long bytes;
 388
 389                 bytes = PAGE_SIZE - offset;
 390                 if (bytes > len)
 391                         bytes = len;
 392                 pb[j].pfn = page_to_pfn(page);
 393                 pb[j].offset = offset;
 394                 pb[j].len = bytes;
 395
 396                 offset += bytes;
 397                 len -= bytes;
 398
 399                 if (offset == PAGE_SIZE && len) {
 400                         page++;
 401                         offset = 0;
 402                         j++;
 403                 }
 404         }
 405
 406         return j + 1;
 407 }
 408
 409 static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
 410                            struct hv_netvsc_packet *packet,
 411                            struct hv_page_buffer *pb)
 412 {
 413         u32 slots_used = 0;
 414         char *data = skb->data;
 415         int frags = skb_shinfo(skb)->nr_frags;
 416         int i;
 417
 418         /* The packet is laid out thus:
 419          * 1. hdr: RNDIS header and PPI
 420          * 2. skb linear data
 421          * 3. skb fragment data
 422          */
 423         slots_used += fill_pg_buf(virt_to_page(hdr),
 424                                   offset_in_page(hdr),
 425                                   len, &pb[slots_used]);
 426
 427         packet->rmsg_size = len;
 428         packet->rmsg_pgcnt = slots_used;
 429
 430         slots_used += fill_pg_buf(virt_to_page(data),
 431                                 offset_in_page(data),
 432                                 skb_headlen(skb), &pb[slots_used]);
 433
 434         for (i = 0; i < frags; i++) {
 435                 skb_frag_t *frag = skb_shinfo(skb)->frags + i;
 436
 437                 slots_used += fill_pg_buf(skb_frag_page(frag),
 438                                         frag->page_offset,
 439                                         skb_frag_size(frag), &pb[slots_used]);
 440         }
 441         return slots_used;
 442 }
 443
 444 static int count_skb_frag_slots(struct sk_buff *skb)
 445 {
 446         int i, frags = skb_shinfo(skb)->nr_frags;
 447         int pages = 0;
 448
 449         for (i = 0; i < frags; i++) {
 450                 skb_frag_t *frag = skb_shinfo(skb)->frags + i;
 451                 unsigned long size = skb_frag_size(frag);
 452                 unsigned long offset = frag->page_offset;
 453
 454                 /* Skip unused frames from start of page */
 455                 offset &= ~PAGE_MASK;
 456                 pages += PFN_UP(offset + size);
 457         }
 458         return pages;
 459 }
 460
 461 static int netvsc_get_slots(struct sk_buff *skb)
 462 {
 463         char *data = skb->data;
 464         unsigned int offset = offset_in_page(data);
 465         unsigned int len = skb_headlen(skb);
 466         int slots;
 467         int frag_slots;
 468
 469         slots = DIV_ROUND_UP(offset + len, PAGE_SIZE);
 470         frag_slots = count_skb_frag_slots(skb);
 471         return slots + frag_slots;
 472 }
 473
 474 static u32 net_checksum_info(struct sk_buff *skb)
 475 {
 476         if (skb->protocol == htons(ETH_P_IP)) {
 477                 struct iphdr *ip = ip_hdr(skb);
 478
 479                 if (ip->protocol == IPPROTO_TCP)
 480                         return TRANSPORT_INFO_IPV4_TCP;
 481                 else if (ip->protocol == IPPROTO_UDP)
 482                         return TRANSPORT_INFO_IPV4_UDP;
 483         } else {
 484                 struct ipv6hdr *ip6 = ipv6_hdr(skb);
 485
 486                 if (ip6->nexthdr == IPPROTO_TCP)
 487                         return TRANSPORT_INFO_IPV6_TCP;
 488                 else if (ip6->nexthdr == IPPROTO_UDP)
 489                         return TRANSPORT_INFO_IPV6_UDP;
 490         }
 491
 492         return TRANSPORT_INFO_NOT_IP;
 493 }
 494
 495 /* Send skb on the slave VF device. */
 496 static int netvsc_vf_xmit(struct net_device *net, struct net_device *vf_netdev,
 497                           struct sk_buff *skb)
 498 {
 499         struct net_device_context *ndev_ctx = netdev_priv(net);
 500         unsigned int len = skb->len;
 501         int rc;
 502
 503         skb->dev = vf_netdev;
 504         skb->queue_mapping = qdisc_skb_cb(skb)->slave_dev_queue_mapping;
 505
 506         rc = dev_queue_xmit(skb);
 507         if (likely(rc == NET_XMIT_SUCCESS || rc == NET_XMIT_CN)) {
 508                 struct netvsc_vf_pcpu_stats *pcpu_stats
 509                         = this_cpu_ptr(ndev_ctx->vf_stats);
 510
 511                 u64_stats_update_begin(&pcpu_stats->syncp);
 512                 pcpu_stats->tx_packets++;
 513                 pcpu_stats->tx_bytes += len;
 514                 u64_stats_update_end(&pcpu_stats->syncp);
 515         } else {
 516                 this_cpu_inc(ndev_ctx->vf_stats->tx_dropped);
 517         }
 518
 519         return rc;
 520 }
 521
 522 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 523 {
 524         struct net_device_context *net_device_ctx = netdev_priv(net);
 525         struct hv_netvsc_packet *packet = NULL;
 526         int ret;
 527         unsigned int num_data_pgs;
 528         struct rndis_message *rndis_msg;
 529         struct net_device *vf_netdev;
 530         u32 rndis_msg_size;
 531         u32 hash;
 532         struct hv_page_buffer pb[MAX_PAGE_BUFFER_COUNT];
 533
 534         /* if VF is present and up then redirect packets
 535          * already called with rcu_read_lock_bh
 536          */
 537         vf_netdev = rcu_dereference_bh(net_device_ctx->vf_netdev);
 538         if (vf_netdev && netif_running(vf_netdev) &&
 539             !netpoll_tx_running(net))
 540                 return netvsc_vf_xmit(net, vf_netdev, skb);
 541
 542         /* We will atmost need two pages to describe the rndis
 543          * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
 544          * of pages in a single packet. If skb is scattered around
 545          * more pages we try linearizing it.
 546          */
 547
 548         num_data_pgs = netvsc_get_slots(skb) + 2;
 549
 550         if (unlikely(num_data_pgs > MAX_PAGE_BUFFER_COUNT)) {
 551                 ++net_device_ctx->eth_stats.tx_scattered;
 552
 553                 if (skb_linearize(skb))
 554                         goto no_memory;
 555
 556                 num_data_pgs = netvsc_get_slots(skb) + 2;
 557                 if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
 558                         ++net_device_ctx->eth_stats.tx_too_big;
 559                         goto drop;
 560                 }
 561         }
 562
 563         /*
 564          * Place the rndis header in the skb head room and
 565          * the skb->cb will be used for hv_netvsc_packet
 566          * structure.
 567          */
 568         ret = skb_cow_head(skb, RNDIS_AND_PPI_SIZE);
 569         if (ret)
 570                 goto no_memory;
 571
 572         /* Use the skb control buffer for building up the packet */
 573         BUILD_BUG_ON(sizeof(struct hv_netvsc_packet) >
 574                         FIELD_SIZEOF(struct sk_buff, cb));
 575         packet = (struct hv_netvsc_packet *)skb->cb;
 576
 577         packet->q_idx = skb_get_queue_mapping(skb);
 578
 579         packet->total_data_buflen = skb->len;
 580         packet->total_bytes = skb->len;
 581         packet->total_packets = 1;
 582
 583         rndis_msg = (struct rndis_message *)skb->head;
 584
 585         /* Add the rndis header */
 586         rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
 587         rndis_msg->msg_len = packet->total_data_buflen;
 588
 589         rndis_msg->msg.pkt = (struct rndis_packet) {
 590                 .data_offset = sizeof(struct rndis_packet),
 591                 .data_len = packet->total_data_buflen,
 592                 .per_pkt_info_offset = sizeof(struct rndis_packet),
 593         };
 594
 595         rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
 596
 597         hash = skb_get_hash_raw(skb);
 598         if (hash != 0 && net->real_num_tx_queues > 1) {
 599                 u32 *hash_info;
 600
 601                 rndis_msg_size += NDIS_HASH_PPI_SIZE;
 602                 hash_info = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
 603                                           NBL_HASH_VALUE);
 604                 *hash_info = hash;
 605         }
 606
 607         if (skb_vlan_tag_present(skb)) {
 608                 struct ndis_pkt_8021q_info *vlan;
 609
 610                 rndis_msg_size += NDIS_VLAN_PPI_SIZE;
 611                 vlan = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
 612                                      IEEE_8021Q_INFO);
 613
 614                 vlan->value = 0;
 615                 vlan->vlanid = skb_vlan_tag_get_id(skb);
 616                 vlan->cfi = skb_vlan_tag_get_cfi(skb);
 617                 vlan->pri = skb_vlan_tag_get_prio(skb);
 618         }
 619
 620         if (skb_is_gso(skb)) {
 621                 struct ndis_tcp_lso_info *lso_info;
 622
 623                 rndis_msg_size += NDIS_LSO_PPI_SIZE;
 624                 lso_info = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
 625                                          TCP_LARGESEND_PKTINFO);
 626
 627                 lso_info->value = 0;
 628                 lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
 629                 if (skb->protocol == htons(ETH_P_IP)) {
 630                         lso_info->lso_v2_transmit.ip_version =
 631                                 NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
 632                         ip_hdr(skb)->tot_len = 0;
 633                         ip_hdr(skb)->check = 0;
 634                         tcp_hdr(skb)->check =
 635                                 ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
 636                                                    ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 637                 } else {
 638                         lso_info->lso_v2_transmit.ip_version =
 639                                 NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
 640                         ipv6_hdr(skb)->payload_len = 0;
 641                         tcp_hdr(skb)->check =
 642                                 ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
 643                                                  &ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 644                 }
 645                 lso_info->lso_v2_transmit.tcp_header_offset = skb_transport_offset(skb);
 646                 lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
 647         } else if (skb->ip_summed == CHECKSUM_PARTIAL) {
 648                 if (net_checksum_info(skb) & net_device_ctx->tx_checksum_mask) {
 649                         struct ndis_tcp_ip_checksum_info *csum_info;
 650
 651                         rndis_msg_size += NDIS_CSUM_PPI_SIZE;
 652                         csum_info = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
 653                                                   TCPIP_CHKSUM_PKTINFO);
 654
 655                         csum_info->value = 0;
 656                         csum_info->transmit.tcp_header_offset = skb_transport_offset(skb);
 657
 658                         if (skb->protocol == htons(ETH_P_IP)) {
 659                                 csum_info->transmit.is_ipv4 = 1;
 660
 661                                 if (ip_hdr(skb)->protocol == IPPROTO_TCP)
 662                                         csum_info->transmit.tcp_checksum = 1;
 663                                 else
 664                                         csum_info->transmit.udp_checksum = 1;
 665                         } else {
 666                                 csum_info->transmit.is_ipv6 = 1;
 667
 668                                 if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
 669                                         csum_info->transmit.tcp_checksum = 1;
 670                                 else
 671                                         csum_info->transmit.udp_checksum = 1;
 672                         }
 673                 } else {
 674                         /* Can't do offload of this type of checksum */
 675                         if (skb_checksum_help(skb))
 676                                 goto drop;
 677                 }
 678         }
 679
 680         /* Start filling in the page buffers with the rndis hdr */
 681         rndis_msg->msg_len += rndis_msg_size;
 682         packet->total_data_buflen = rndis_msg->msg_len;
 683         packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
 684                                                skb, packet, pb);
 685
 686         /* timestamp packet in software */
 687         skb_tx_timestamp(skb);
 688
 689         ret = netvsc_send(net, packet, rndis_msg, pb, skb);
 690         if (likely(ret == 0))
 691                 return NETDEV_TX_OK;
 692
 693         if (ret == -EAGAIN) {
 694                 ++net_device_ctx->eth_stats.tx_busy;
 695                 return NETDEV_TX_BUSY;
 696         }
 697
 698         if (ret == -ENOSPC)
 699                 ++net_device_ctx->eth_stats.tx_no_space;
 700
 701 drop:
 702         dev_kfree_skb_any(skb);
 703         net->stats.tx_dropped++;
 704
 705         return NETDEV_TX_OK;
 706
 707 no_memory:
 708         ++net_device_ctx->eth_stats.tx_no_memory;
 709         goto drop;
 710 }
 711
 712 /*
 713  * netvsc_linkstatus_callback - Link up/down notification
 714  */
 715 void netvsc_linkstatus_callback(struct net_device *net,
 716                                 struct rndis_message *resp)
 717 {
 718         struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
 719         struct net_device_context *ndev_ctx = netdev_priv(net);
 720         struct netvsc_reconfig *event;
 721         unsigned long flags;
 722
 723         /* Update the physical link speed when changing to another vSwitch */
 724         if (indicate->status == RNDIS_STATUS_LINK_SPEED_CHANGE) {
 725                 u32 speed;
 726
 727                 speed = *(u32 *)((void *)indicate
 728                                  + indicate->status_buf_offset) / 10000;
 729                 ndev_ctx->speed = speed;
 730                 return;
 731         }
 732
 733         /* Handle these link change statuses below */
 734         if (indicate->status != RNDIS_STATUS_NETWORK_CHANGE &&
 735             indicate->status != RNDIS_STATUS_MEDIA_CONNECT &&
 736             indicate->status != RNDIS_STATUS_MEDIA_DISCONNECT)
 737                 return;
 738
 739         if (net->reg_state != NETREG_REGISTERED)
 740                 return;
 741
 742         event = kzalloc(sizeof(*event), GFP_ATOMIC);
 743         if (!event)
 744                 return;
 745         event->event = indicate->status;
 746
 747         spin_lock_irqsave(&ndev_ctx->lock, flags);
 748         list_add_tail(&event->list, &ndev_ctx->reconfig_events);
 749         spin_unlock_irqrestore(&ndev_ctx->lock, flags);
 750
 751         schedule_delayed_work(&ndev_ctx->dwork, 0);
 752 }
 753
 754 static void netvsc_comp_ipcsum(struct sk_buff *skb)
 755 {
 756         struct iphdr *iph = (struct iphdr *)skb->data;
 757
 758         iph->check = 0;
 759         iph->check = ip_fast_csum(iph, iph->ihl);
 760 }
 761
 762 static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net,
 763                                              struct netvsc_channel *nvchan)
 764 {
 765         struct napi_struct *napi = &nvchan->napi;
 766         const struct ndis_pkt_8021q_info *vlan = nvchan->rsc.vlan;
 767         const struct ndis_tcp_ip_checksum_info *csum_info =
 768                                                 nvchan->rsc.csum_info;
 769         struct sk_buff *skb;
 770         int i;
 771
 772         skb = napi_alloc_skb(napi, nvchan->rsc.pktlen);
 773         if (!skb)
 774                 return skb;
 775
 776         /*
 777          * Copy to skb. This copy is needed here since the memory pointed by
 778          * hv_netvsc_packet cannot be deallocated
 779          */
 780         for (i = 0; i < nvchan->rsc.cnt; i++)
 781                 skb_put_data(skb, nvchan->rsc.data[i], nvchan->rsc.len[i]);
 782
 783         skb->protocol = eth_type_trans(skb, net);
 784
 785         /* skb is already created with CHECKSUM_NONE */
 786         skb_checksum_none_assert(skb);
 787
 788         /* Incoming packets may have IP header checksum verified by the host.
 789          * They may not have IP header checksum computed after coalescing.
 790          * We compute it here if the flags are set, because on Linux, the IP
 791          * checksum is always checked.
 792          */
 793         if (csum_info && csum_info->receive.ip_checksum_value_invalid &&
 794             csum_info->receive.ip_checksum_succeeded &&
 795             skb->protocol == htons(ETH_P_IP))
 796                 netvsc_comp_ipcsum(skb);
 797
 798         /* Do L4 checksum offload if enabled and present.
 799          */
 800         if (csum_info && (net->features & NETIF_F_RXCSUM)) {
 801                 if (csum_info->receive.tcp_checksum_succeeded ||
 802                     csum_info->receive.udp_checksum_succeeded)
 803                         skb->ip_summed = CHECKSUM_UNNECESSARY;
 804         }
 805
 806         if (vlan) {
 807                 u16 vlan_tci = vlan->vlanid | (vlan->pri << VLAN_PRIO_SHIFT) |
 808                         (vlan->cfi ? VLAN_CFI_MASK : 0);
 809
 810                 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 811                                        vlan_tci);
 812         }
 813
 814         return skb;
 815 }
 816
 817 /*
 818  * netvsc_recv_callback -  Callback when we receive a packet from the
 819  * "wire" on the specified device.
 820  */
 821 int netvsc_recv_callback(struct net_device *net,
 822                          struct netvsc_device *net_device,
 823                          struct netvsc_channel *nvchan)
 824 {
 825         struct net_device_context *net_device_ctx = netdev_priv(net);
 826         struct vmbus_channel *channel = nvchan->channel;
 827         u16 q_idx = channel->offermsg.offer.sub_channel_index;
 828         struct sk_buff *skb;
 829         struct netvsc_stats *rx_stats;
 830
 831         if (net->reg_state != NETREG_REGISTERED)
 832                 return NVSP_STAT_FAIL;
 833
 834         /* Allocate a skb - TODO direct I/O to pages? */
 835         skb = netvsc_alloc_recv_skb(net, nvchan);
 836
 837         if (unlikely(!skb)) {
 838                 ++net_device_ctx->eth_stats.rx_no_memory;
 839                 return NVSP_STAT_FAIL;
 840         }
 841
 842         skb_record_rx_queue(skb, q_idx);
 843
 844         /*
 845          * Even if injecting the packet, record the statistics
 846          * on the synthetic device because modifying the VF device
 847          * statistics will not work correctly.
 848          */
 849         rx_stats = &nvchan->rx_stats;
 850         u64_stats_update_begin(&rx_stats->syncp);
 851         rx_stats->packets++;
 852         rx_stats->bytes += nvchan->rsc.pktlen;
 853
 854         if (skb->pkt_type == PACKET_BROADCAST)
 855                 ++rx_stats->broadcast;
 856         else if (skb->pkt_type == PACKET_MULTICAST)
 857                 ++rx_stats->multicast;
 858         u64_stats_update_end(&rx_stats->syncp);
 859
 860         napi_gro_receive(&nvchan->napi, skb);
 861         return NVSP_STAT_SUCCESS;
 862 }
 863
 864 static void netvsc_get_drvinfo(struct net_device *net,
 865                                struct ethtool_drvinfo *info)
 866 {
 867         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 868         strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
 869 }
 870
 871 static void netvsc_get_channels(struct net_device *net,
 872                                 struct ethtool_channels *channel)
 873 {
 874         struct net_device_context *net_device_ctx = netdev_priv(net);
 875         struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 876
 877         if (nvdev) {
 878                 channel->max_combined   = nvdev->max_chn;
 879                 channel->combined_count = nvdev->num_chn;
 880         }
 881 }
 882
 883 /* Alloc struct netvsc_device_info, and initialize it from either existing
 884  * struct netvsc_device, or from default values.
 885  */
 886 static struct netvsc_device_info *netvsc_devinfo_get
 887                         (struct netvsc_device *nvdev)
 888 {
 889         struct netvsc_device_info *dev_info;
 890
 891         dev_info = kzalloc(sizeof(*dev_info), GFP_ATOMIC);
 892
 893         if (!dev_info)
 894                 return NULL;
 895
 896         if (nvdev) {
 897                 dev_info->num_chn = nvdev->num_chn;
 898                 dev_info->send_sections = nvdev->send_section_cnt;
 899                 dev_info->send_section_size = nvdev->send_section_size;
 900                 dev_info->recv_sections = nvdev->recv_section_cnt;
 901                 dev_info->recv_section_size = nvdev->recv_section_size;
 902
 903                 memcpy(dev_info->rss_key, nvdev->extension->rss_key,
 904                        NETVSC_HASH_KEYLEN);
 905         } else {
 906                 dev_info->num_chn = VRSS_CHANNEL_DEFAULT;
 907                 dev_info->send_sections = NETVSC_DEFAULT_TX;
 908                 dev_info->send_section_size = NETVSC_SEND_SECTION_SIZE;
 909                 dev_info->recv_sections = NETVSC_DEFAULT_RX;
 910                 dev_info->recv_section_size = NETVSC_RECV_SECTION_SIZE;
 911         }
 912
 913         return dev_info;
 914 }
 915
 916 static int netvsc_detach(struct net_device *ndev,
 917                          struct netvsc_device *nvdev)
 918 {
 919         struct net_device_context *ndev_ctx = netdev_priv(ndev);
 920         struct hv_device *hdev = ndev_ctx->device_ctx;
 921         int ret;
 922
 923         /* Don't try continuing to try and setup sub channels */
 924         if (cancel_work_sync(&nvdev->subchan_work))
 925                 nvdev->num_chn = 1;
 926
 927         /* If device was up (receiving) then shutdown */
 928         if (netif_running(ndev)) {
 929                 netvsc_tx_disable(nvdev, ndev);
 930
 931                 ret = rndis_filter_close(nvdev);
 932                 if (ret) {
 933                         netdev_err(ndev,
 934                                    "unable to close device (ret %d).\n", ret);
 935                         return ret;
 936                 }
 937
 938                 ret = netvsc_wait_until_empty(nvdev);
 939                 if (ret) {
 940                         netdev_err(ndev,
 941                                    "Ring buffer not empty after closing rndis\n");
 942                         return ret;
 943                 }
 944         }
 945
 946         netif_device_detach(ndev);
 947
 948         rndis_filter_device_remove(hdev, nvdev);
 949
 950         return 0;
 951 }
 952
 953 static int netvsc_attach(struct net_device *ndev,
 954                          struct netvsc_device_info *dev_info)
 955 {
 956         struct net_device_context *ndev_ctx = netdev_priv(ndev);
 957         struct hv_device *hdev = ndev_ctx->device_ctx;
 958         struct netvsc_device *nvdev;
 959         struct rndis_device *rdev;
 960         int ret;
 961
 962         nvdev = rndis_filter_device_add(hdev, dev_info);
 963         if (IS_ERR(nvdev))
 964                 return PTR_ERR(nvdev);
 965
 966         if (nvdev->num_chn > 1) {
 967                 ret = rndis_set_subchannel(ndev, nvdev, dev_info);
 968
 969                 /* if unavailable, just proceed with one queue */
 970                 if (ret) {
 971                         nvdev->max_chn = 1;
 972                         nvdev->num_chn = 1;
 973                 }
 974         }
 975
 976         /* In any case device is now ready */
 977         netif_device_attach(ndev);
 978
 979         /* Note: enable and attach happen when sub-channels setup */
 980         netif_carrier_off(ndev);
 981
 982         if (netif_running(ndev)) {
 983                 ret = rndis_filter_open(nvdev);
 984                 if (ret)
 985                         return ret;
 986
 987                 rdev = nvdev->extension;
 988                 if (!rdev->link_state)
 989                         netif_carrier_on(ndev);
 990         }
 991
 992         return 0;
 993 }
 994
 995 static int netvsc_set_channels(struct net_device *net,
 996                                struct ethtool_channels *channels)
 997 {
 998         struct net_device_context *net_device_ctx = netdev_priv(net);
 999         struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
1000         unsigned int orig, count = channels->combined_count;
1001         struct netvsc_device_info *device_info;
1002         int ret;
1003
1004         /* We do not support separate count for rx, tx, or other */
1005         if (count == 0 ||
1006             channels->rx_count || channels->tx_count || channels->other_count)
1007                 return -EINVAL;
1008
1009         if (!nvdev || nvdev->destroy)
1010                 return -ENODEV;
1011
1012         if (nvdev->nvsp_version < NVSP_PROTOCOL_VERSION_5)
1013                 return -EINVAL;
1014
1015         if (count > nvdev->max_chn)
1016                 return -EINVAL;
1017
1018         orig = nvdev->num_chn;
1019
1020         device_info = netvsc_devinfo_get(nvdev);
1021
1022         if (!device_info)
1023                 return -ENOMEM;
1024
1025         device_info->num_chn = count;
1026
1027         ret = netvsc_detach(net, nvdev);
1028         if (ret)
1029                 goto out;
1030
1031         ret = netvsc_attach(net, device_info);
1032         if (ret) {
1033                 device_info->num_chn = orig;
1034                 if (netvsc_attach(net, device_info))
1035                         netdev_err(net, "restoring channel setting failed\n");
1036         }
1037
1038 out:
1039         kfree(device_info);
1040         return ret;
1041 }
1042
1043 static bool
1044 netvsc_validate_ethtool_ss_cmd(const struct ethtool_link_ksettings *cmd)
1045 {
1046         struct ethtool_link_ksettings diff1 = *cmd;
1047         struct ethtool_link_ksettings diff2 = {};
1048
1049         diff1.base.speed = 0;
1050         diff1.base.duplex = 0;
1051         /* advertising and cmd are usually set */
1052         ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
1053         diff1.base.cmd = 0;
1054         /* We set port to PORT_OTHER */
1055         diff2.base.port = PORT_OTHER;
1056
1057         return !memcmp(&diff1, &diff2, sizeof(diff1));
1058 }
1059
1060 static void netvsc_init_settings(struct net_device *dev)
1061 {
1062         struct net_device_context *ndc = netdev_priv(dev);
1063
1064         ndc->l4_hash = HV_DEFAULT_L4HASH;
1065
1066         ndc->speed = SPEED_UNKNOWN;
1067         ndc->duplex = DUPLEX_FULL;
1068
1069         dev->features = NETIF_F_LRO;
1070 }
1071
1072 static int netvsc_get_link_ksettings(struct net_device *dev,
1073                                      struct ethtool_link_ksettings *cmd)
1074 {
1075         struct net_device_context *ndc = netdev_priv(dev);
1076
1077         cmd->base.speed = ndc->speed;
1078         cmd->base.duplex = ndc->duplex;
1079         cmd->base.port = PORT_OTHER;
1080
1081         return 0;
1082 }
1083
1084 static int netvsc_set_link_ksettings(struct net_device *dev,
1085                                      const struct ethtool_link_ksettings *cmd)
1086 {
1087         struct net_device_context *ndc = netdev_priv(dev);
1088         u32 speed;
1089
1090         speed = cmd->base.speed;
1091         if (!ethtool_validate_speed(speed) ||
1092             !ethtool_validate_duplex(cmd->base.duplex) ||
1093             !netvsc_validate_ethtool_ss_cmd(cmd))
1094                 return -EINVAL;
1095
1096         ndc->speed = speed;
1097         ndc->duplex = cmd->base.duplex;
1098
1099         return 0;
1100 }
1101
1102 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
1103 {
1104         struct net_device_context *ndevctx = netdev_priv(ndev);
1105         struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
1106         struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1107         int orig_mtu = ndev->mtu;
1108         struct netvsc_device_info *device_info;
1109         int ret = 0;
1110
1111         if (!nvdev || nvdev->destroy)
1112                 return -ENODEV;
1113
1114         device_info = netvsc_devinfo_get(nvdev);
1115
1116         if (!device_info)
1117                 return -ENOMEM;
1118
1119         /* Change MTU of underlying VF netdev first. */
1120         if (vf_netdev) {
1121                 ret = dev_set_mtu(vf_netdev, mtu);
1122                 if (ret)
1123                         goto out;
1124         }
1125
1126         ret = netvsc_detach(ndev, nvdev);
1127         if (ret)
1128                 goto rollback_vf;
1129
1130         ndev->mtu = mtu;
1131
1132         ret = netvsc_attach(ndev, device_info);
1133         if (!ret)
1134                 goto out;
1135
1136         /* Attempt rollback to original MTU */
1137         ndev->mtu = orig_mtu;
1138
1139         if (netvsc_attach(ndev, device_info))
1140                 netdev_err(ndev, "restoring mtu failed\n");
1141 rollback_vf:
1142         if (vf_netdev)
1143                 dev_set_mtu(vf_netdev, orig_mtu);
1144
1145 out:
1146         kfree(device_info);
1147         return ret;
1148 }
1149
1150 static void netvsc_get_vf_stats(struct net_device *net,
1151                                 struct netvsc_vf_pcpu_stats *tot)
1152 {
1153         struct net_device_context *ndev_ctx = netdev_priv(net);
1154         int i;
1155
1156         memset(tot, 0, sizeof(*tot));
1157
1158         for_each_possible_cpu(i) {
1159                 const struct netvsc_vf_pcpu_stats *stats
1160                         = per_cpu_ptr(ndev_ctx->vf_stats, i);
1161                 u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
1162                 unsigned int start;
1163
1164                 do {
1165                         start = u64_stats_fetch_begin_irq(&stats->syncp);
1166                         rx_packets = stats->rx_packets;
1167                         tx_packets = stats->tx_packets;
1168                         rx_bytes = stats->rx_bytes;
1169                         tx_bytes = stats->tx_bytes;
1170                 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1171
1172                 tot->rx_packets += rx_packets;
1173                 tot->tx_packets += tx_packets;
1174                 tot->rx_bytes   += rx_bytes;
1175                 tot->tx_bytes   += tx_bytes;
1176                 tot->tx_dropped += stats->tx_dropped;
1177         }
1178 }
1179
1180 static void netvsc_get_pcpu_stats(struct net_device *net,
1181                                   struct netvsc_ethtool_pcpu_stats *pcpu_tot)
1182 {
1183         struct net_device_context *ndev_ctx = netdev_priv(net);
1184         struct netvsc_device *nvdev = rcu_dereference_rtnl(ndev_ctx->nvdev);
1185         int i;
1186
1187         /* fetch percpu stats of vf */
1188         for_each_possible_cpu(i) {
1189                 const struct netvsc_vf_pcpu_stats *stats =
1190                         per_cpu_ptr(ndev_ctx->vf_stats, i);
1191                 struct netvsc_ethtool_pcpu_stats *this_tot = &pcpu_tot[i];
1192                 unsigned int start;
1193
1194                 do {
1195                         start = u64_stats_fetch_begin_irq(&stats->syncp);
1196                         this_tot->vf_rx_packets = stats->rx_packets;
1197                         this_tot->vf_tx_packets = stats->tx_packets;
1198                         this_tot->vf_rx_bytes = stats->rx_bytes;
1199                         this_tot->vf_tx_bytes = stats->tx_bytes;
1200                 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1201                 this_tot->rx_packets = this_tot->vf_rx_packets;
1202                 this_tot->tx_packets = this_tot->vf_tx_packets;
1203                 this_tot->rx_bytes   = this_tot->vf_rx_bytes;
1204                 this_tot->tx_bytes   = this_tot->vf_tx_bytes;
1205         }
1206
1207         /* fetch percpu stats of netvsc */
1208         for (i = 0; i < nvdev->num_chn; i++) {
1209                 const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
1210                 const struct netvsc_stats *stats;
1211                 struct netvsc_ethtool_pcpu_stats *this_tot =
1212                         &pcpu_tot[nvchan->channel->target_cpu];
1213                 u64 packets, bytes;
1214                 unsigned int start;
1215
1216                 stats = &nvchan->tx_stats;
1217                 do {
1218                         start = u64_stats_fetch_begin_irq(&stats->syncp);
1219                         packets = stats->packets;
1220                         bytes = stats->bytes;
1221                 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1222
1223                 this_tot->tx_bytes      += bytes;
1224                 this_tot->tx_packets    += packets;
1225
1226                 stats = &nvchan->rx_stats;
1227                 do {
1228                         start = u64_stats_fetch_begin_irq(&stats->syncp);
1229                         packets = stats->packets;
1230                         bytes = stats->bytes;
1231                 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1232
1233                 this_tot->rx_bytes      += bytes;
1234                 this_tot->rx_packets    += packets;
1235         }
1236 }
1237
1238 static void netvsc_get_stats64(struct net_device *net,
1239                                struct rtnl_link_stats64 *t)
1240 {
1241         struct net_device_context *ndev_ctx = netdev_priv(net);
1242         struct netvsc_device *nvdev;
1243         struct netvsc_vf_pcpu_stats vf_tot;
1244         int i;
1245
1246         rcu_read_lock();
1247
1248         nvdev = rcu_dereference(ndev_ctx->nvdev);
1249         if (!nvdev)
1250                 goto out;
1251
1252         netdev_stats_to_stats64(t, &net->stats);
1253
1254         netvsc_get_vf_stats(net, &vf_tot);
1255         t->rx_packets += vf_tot.rx_packets;
1256         t->tx_packets += vf_tot.tx_packets;
1257         t->rx_bytes   += vf_tot.rx_bytes;
1258         t->tx_bytes   += vf_tot.tx_bytes;
1259         t->tx_dropped += vf_tot.tx_dropped;
1260
1261         for (i = 0; i < nvdev->num_chn; i++) {
1262                 const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
1263                 const struct netvsc_stats *stats;
1264                 u64 packets, bytes, multicast;
1265                 unsigned int start;
1266
1267                 stats = &nvchan->tx_stats;
1268                 do {
1269                         start = u64_stats_fetch_begin_irq(&stats->syncp);
1270                         packets = stats->packets;
1271                         bytes = stats->bytes;
1272                 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1273
1274                 t->tx_bytes     += bytes;
1275                 t->tx_packets   += packets;
1276
1277                 stats = &nvchan->rx_stats;
1278                 do {
1279                         start = u64_stats_fetch_begin_irq(&stats->syncp);
1280                         packets = stats->packets;
1281                         bytes = stats->bytes;
1282                         multicast = stats->multicast + stats->broadcast;
1283                 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1284
1285                 t->rx_bytes     += bytes;
1286                 t->rx_packets   += packets;
1287                 t->multicast    += multicast;
1288         }
1289 out:
1290         rcu_read_unlock();
1291 }
1292
1293 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
1294 {
1295         struct net_device_context *ndc = netdev_priv(ndev);
1296         struct net_device *vf_netdev = rtnl_dereference(ndc->vf_netdev);
1297         struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1298         struct sockaddr *addr = p;
1299         int err;
1300
1301         err = eth_prepare_mac_addr_change(ndev, p);
1302         if (err)
1303                 return err;
1304
1305         if (!nvdev)
1306                 return -ENODEV;
1307
1308         if (vf_netdev) {
1309                 err = dev_set_mac_address(vf_netdev, addr, NULL);
1310                 if (err)
1311                         return err;
1312         }
1313
1314         err = rndis_filter_set_device_mac(nvdev, addr->sa_data);
1315         if (!err) {
1316                 eth_commit_mac_addr_change(ndev, p);
1317         } else if (vf_netdev) {
1318                 /* rollback change on VF */
1319                 memcpy(addr->sa_data, ndev->dev_addr, ETH_ALEN);
1320                 dev_set_mac_address(vf_netdev, addr, NULL);
1321         }
1322
1323         return err;
1324 }
1325
1326 static const struct {
1327         char name[ETH_GSTRING_LEN];
1328         u16 offset;
1329 } netvsc_stats[] = {
1330         { "tx_scattered", offsetof(struct netvsc_ethtool_stats, tx_scattered) },
1331         { "tx_no_memory", offsetof(struct netvsc_ethtool_stats, tx_no_memory) },
1332         { "tx_no_space",  offsetof(struct netvsc_ethtool_stats, tx_no_space) },
1333         { "tx_too_big",   offsetof(struct netvsc_ethtool_stats, tx_too_big) },
1334         { "tx_busy",      offsetof(struct netvsc_ethtool_stats, tx_busy) },
1335         { "tx_send_full", offsetof(struct netvsc_ethtool_stats, tx_send_full) },
1336         { "rx_comp_busy", offsetof(struct netvsc_ethtool_stats, rx_comp_busy) },
1337         { "rx_no_memory", offsetof(struct netvsc_ethtool_stats, rx_no_memory) },
1338         { "stop_queue", offsetof(struct netvsc_ethtool_stats, stop_queue) },
1339         { "wake_queue", offsetof(struct netvsc_ethtool_stats, wake_queue) },
1340 }, pcpu_stats[] = {
1341         { "cpu%u_rx_packets",
1342                 offsetof(struct netvsc_ethtool_pcpu_stats, rx_packets) },
1343         { "cpu%u_rx_bytes",
1344                 offsetof(struct netvsc_ethtool_pcpu_stats, rx_bytes) },
1345         { "cpu%u_tx_packets",
1346                 offsetof(struct netvsc_ethtool_pcpu_stats, tx_packets) },
1347         { "cpu%u_tx_bytes",
1348                 offsetof(struct netvsc_ethtool_pcpu_stats, tx_bytes) },
1349         { "cpu%u_vf_rx_packets",
1350                 offsetof(struct netvsc_ethtool_pcpu_stats, vf_rx_packets) },
1351         { "cpu%u_vf_rx_bytes",
1352                 offsetof(struct netvsc_ethtool_pcpu_stats, vf_rx_bytes) },
1353         { "cpu%u_vf_tx_packets",
1354                 offsetof(struct netvsc_ethtool_pcpu_stats, vf_tx_packets) },
1355         { "cpu%u_vf_tx_bytes",
1356                 offsetof(struct netvsc_ethtool_pcpu_stats, vf_tx_bytes) },
1357 }, vf_stats[] = {
1358         { "vf_rx_packets", offsetof(struct netvsc_vf_pcpu_stats, rx_packets) },
1359         { "vf_rx_bytes",   offsetof(struct netvsc_vf_pcpu_stats, rx_bytes) },
1360         { "vf_tx_packets", offsetof(struct netvsc_vf_pcpu_stats, tx_packets) },
1361         { "vf_tx_bytes",   offsetof(struct netvsc_vf_pcpu_stats, tx_bytes) },
1362         { "vf_tx_dropped", offsetof(struct netvsc_vf_pcpu_stats, tx_dropped) },
1363 };
1364
1365 #define NETVSC_GLOBAL_STATS_LEN ARRAY_SIZE(netvsc_stats)
1366 #define NETVSC_VF_STATS_LEN     ARRAY_SIZE(vf_stats)
1367
1368 /* statistics per queue (rx/tx packets/bytes) */
1369 #define NETVSC_PCPU_STATS_LEN (num_present_cpus() * ARRAY_SIZE(pcpu_stats))
1370
1371 /* 4 statistics per queue (rx/tx packets/bytes) */
1372 #define NETVSC_QUEUE_STATS_LEN(dev) ((dev)->num_chn * 4)
1373
1374 static int netvsc_get_sset_count(struct net_device *dev, int string_set)
1375 {
1376         struct net_device_context *ndc = netdev_priv(dev);
1377         struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1378
1379         if (!nvdev)
1380                 return -ENODEV;
1381
1382         switch (string_set) {
1383         case ETH_SS_STATS:
1384                 return NETVSC_GLOBAL_STATS_LEN
1385                         + NETVSC_VF_STATS_LEN
1386                         + NETVSC_QUEUE_STATS_LEN(nvdev)
1387                         + NETVSC_PCPU_STATS_LEN;
1388         default:
1389                 return -EINVAL;
1390         }
1391 }
1392
1393 static void netvsc_get_ethtool_stats(struct net_device *dev,
1394                                      struct ethtool_stats *stats, u64 *data)
1395 {
1396         struct net_device_context *ndc = netdev_priv(dev);
1397         struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1398         const void *nds = &ndc->eth_stats;
1399         const struct netvsc_stats *qstats;
1400         struct netvsc_vf_pcpu_stats sum;
1401         struct netvsc_ethtool_pcpu_stats *pcpu_sum;
1402         unsigned int start;
1403         u64 packets, bytes;
1404         int i, j, cpu;
1405
1406         if (!nvdev)
1407                 return;
1408
1409         for (i = 0; i < NETVSC_GLOBAL_STATS_LEN; i++)
1410                 data[i] = *(unsigned long *)(nds + netvsc_stats[i].offset);
1411
1412         netvsc_get_vf_stats(dev, &sum);
1413         for (j = 0; j < NETVSC_VF_STATS_LEN; j++)
1414                 data[i++] = *(u64 *)((void *)&sum + vf_stats[j].offset);
1415
1416         for (j = 0; j < nvdev->num_chn; j++) {
1417                 qstats = &nvdev->chan_table[j].tx_stats;
1418
1419                 do {
1420                         start = u64_stats_fetch_begin_irq(&qstats->syncp);
1421                         packets = qstats->packets;
1422                         bytes = qstats->bytes;
1423                 } while (u64_stats_fetch_retry_irq(&qstats->syncp, start));
1424                 data[i++] = packets;
1425                 data[i++] = bytes;
1426
1427                 qstats = &nvdev->chan_table[j].rx_stats;
1428                 do {
1429                         start = u64_stats_fetch_begin_irq(&qstats->syncp);
1430                         packets = qstats->packets;
1431                         bytes = qstats->bytes;
1432                 } while (u64_stats_fetch_retry_irq(&qstats->syncp, start));
1433                 data[i++] = packets;
1434                 data[i++] = bytes;
1435         }
1436
1437         pcpu_sum = kvmalloc_array(num_possible_cpus(),
1438                                   sizeof(struct netvsc_ethtool_pcpu_stats),
1439                                   GFP_KERNEL);
1440         netvsc_get_pcpu_stats(dev, pcpu_sum);
1441         for_each_present_cpu(cpu) {
1442                 struct netvsc_ethtool_pcpu_stats *this_sum = &pcpu_sum[cpu];
1443
1444                 for (j = 0; j < ARRAY_SIZE(pcpu_stats); j++)
1445                         data[i++] = *(u64 *)((void *)this_sum
1446                                              + pcpu_stats[j].offset);
1447         }
1448         kvfree(pcpu_sum);
1449 }
1450
1451 static void netvsc_get_strings(struct net_device *dev, u32 stringset, u8 *data)
1452 {
1453         struct net_device_context *ndc = netdev_priv(dev);
1454         struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1455         u8 *p = data;
1456         int i, cpu;
1457
1458         if (!nvdev)
1459                 return;
1460
1461         switch (stringset) {
1462         case ETH_SS_STATS:
1463                 for (i = 0; i < ARRAY_SIZE(netvsc_stats); i++) {
1464                         memcpy(p, netvsc_stats[i].name, ETH_GSTRING_LEN);
1465                         p += ETH_GSTRING_LEN;
1466                 }
1467
1468                 for (i = 0; i < ARRAY_SIZE(vf_stats); i++) {
1469                         memcpy(p, vf_stats[i].name, ETH_GSTRING_LEN);
1470                         p += ETH_GSTRING_LEN;
1471                 }
1472
1473                 for (i = 0; i < nvdev->num_chn; i++) {
1474                         sprintf(p, "tx_queue_%u_packets", i);
1475                         p += ETH_GSTRING_LEN;
1476                         sprintf(p, "tx_queue_%u_bytes", i);
1477                         p += ETH_GSTRING_LEN;
1478                         sprintf(p, "rx_queue_%u_packets", i);
1479                         p += ETH_GSTRING_LEN;
1480                         sprintf(p, "rx_queue_%u_bytes", i);
1481                         p += ETH_GSTRING_LEN;
1482                 }
1483
1484                 for_each_present_cpu(cpu) {
1485                         for (i = 0; i < ARRAY_SIZE(pcpu_stats); i++) {
1486                                 sprintf(p, pcpu_stats[i].name, cpu);
1487                                 p += ETH_GSTRING_LEN;
1488                         }
1489                 }
1490
1491                 break;
1492         }
1493 }
1494
1495 static int
1496 netvsc_get_rss_hash_opts(struct net_device_context *ndc,
1497                          struct ethtool_rxnfc *info)
1498 {
1499         const u32 l4_flag = RXH_L4_B_0_1 | RXH_L4_B_2_3;
1500
1501         info->data = RXH_IP_SRC | RXH_IP_DST;
1502
1503         switch (info->flow_type) {
1504         case TCP_V4_FLOW:
1505                 if (ndc->l4_hash & HV_TCP4_L4HASH)
1506                         info->data |= l4_flag;
1507
1508                 break;
1509
1510         case TCP_V6_FLOW:
1511                 if (ndc->l4_hash & HV_TCP6_L4HASH)
1512                         info->data |= l4_flag;
1513
1514                 break;
1515
1516         case UDP_V4_FLOW:
1517                 if (ndc->l4_hash & HV_UDP4_L4HASH)
1518                         info->data |= l4_flag;
1519
1520                 break;
1521
1522         case UDP_V6_FLOW:
1523                 if (ndc->l4_hash & HV_UDP6_L4HASH)
1524                         info->data |= l4_flag;
1525
1526                 break;
1527
1528         case IPV4_FLOW:
1529         case IPV6_FLOW:
1530                 break;
1531         default:
1532                 info->data = 0;
1533                 break;
1534         }
1535
1536         return 0;
1537 }
1538
1539 static int
1540 netvsc_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
1541                  u32 *rules)
1542 {
1543         struct net_device_context *ndc = netdev_priv(dev);
1544         struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1545
1546         if (!nvdev)
1547                 return -ENODEV;
1548
1549         switch (info->cmd) {
1550         case ETHTOOL_GRXRINGS:
1551                 info->data = nvdev->num_chn;
1552                 return 0;
1553
1554         case ETHTOOL_GRXFH:
1555                 return netvsc_get_rss_hash_opts(ndc, info);
1556         }
1557         return -EOPNOTSUPP;
1558 }
1559
1560 static int netvsc_set_rss_hash_opts(struct net_device_context *ndc,
1561                                     struct ethtool_rxnfc *info)
1562 {
1563         if (info->data == (RXH_IP_SRC | RXH_IP_DST |
1564                            RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
1565                 switch (info->flow_type) {
1566                 case TCP_V4_FLOW:
1567                         ndc->l4_hash |= HV_TCP4_L4HASH;
1568                         break;
1569
1570                 case TCP_V6_FLOW:
1571                         ndc->l4_hash |= HV_TCP6_L4HASH;
1572                         break;
1573
1574                 case UDP_V4_FLOW:
1575                         ndc->l4_hash |= HV_UDP4_L4HASH;
1576                         break;
1577
1578                 case UDP_V6_FLOW:
1579                         ndc->l4_hash |= HV_UDP6_L4HASH;
1580                         break;
1581
1582                 default:
1583                         return -EOPNOTSUPP;
1584                 }
1585
1586                 return 0;
1587         }
1588
1589         if (info->data == (RXH_IP_SRC | RXH_IP_DST)) {
1590                 switch (info->flow_type) {
1591                 case TCP_V4_FLOW:
1592                         ndc->l4_hash &= ~HV_TCP4_L4HASH;
1593                         break;
1594
1595                 case TCP_V6_FLOW:
1596                         ndc->l4_hash &= ~HV_TCP6_L4HASH;
1597                         break;
1598
1599                 case UDP_V4_FLOW:
1600                         ndc->l4_hash &= ~HV_UDP4_L4HASH;
1601                         break;
1602
1603                 case UDP_V6_FLOW:
1604                         ndc->l4_hash &= ~HV_UDP6_L4HASH;
1605                         break;
1606
1607                 default:
1608                         return -EOPNOTSUPP;
1609                 }
1610
1611                 return 0;
1612         }
1613
1614         return -EOPNOTSUPP;
1615 }
1616
1617 static int
1618 netvsc_set_rxnfc(struct net_device *ndev, struct ethtool_rxnfc *info)
1619 {
1620         struct net_device_context *ndc = netdev_priv(ndev);
1621
1622         if (info->cmd == ETHTOOL_SRXFH)
1623                 return netvsc_set_rss_hash_opts(ndc, info);
1624
1625         return -EOPNOTSUPP;
1626 }
1627
1628 static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
1629 {
1630         return NETVSC_HASH_KEYLEN;
1631 }
1632
1633 static u32 netvsc_rss_indir_size(struct net_device *dev)
1634 {
1635         return ITAB_NUM;
1636 }
1637
1638 static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
1639                            u8 *hfunc)
1640 {
1641         struct net_device_context *ndc = netdev_priv(dev);
1642         struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1643         struct rndis_device *rndis_dev;
1644         int i;
1645
1646         if (!ndev)
1647                 return -ENODEV;
1648
1649         if (hfunc)
1650                 *hfunc = ETH_RSS_HASH_TOP;      /* Toeplitz */
1651
1652         rndis_dev = ndev->extension;
1653         if (indir) {
1654                 for (i = 0; i < ITAB_NUM; i++)
1655                         indir[i] = rndis_dev->rx_table[i];
1656         }
1657
1658         if (key)
1659                 memcpy(key, rndis_dev->rss_key, NETVSC_HASH_KEYLEN);
1660
1661         return 0;
1662 }
1663
1664 static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
1665                            const u8 *key, const u8 hfunc)
1666 {
1667         struct net_device_context *ndc = netdev_priv(dev);
1668         struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1669         struct rndis_device *rndis_dev;
1670         int i;
1671
1672         if (!ndev)
1673                 return -ENODEV;
1674
1675         if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
1676                 return -EOPNOTSUPP;
1677
1678         rndis_dev = ndev->extension;
1679         if (indir) {
1680                 for (i = 0; i < ITAB_NUM; i++)
1681                         if (indir[i] >= ndev->num_chn)
1682                                 return -EINVAL;
1683
1684                 for (i = 0; i < ITAB_NUM; i++)
1685                         rndis_dev->rx_table[i] = indir[i];
1686         }
1687
1688         if (!key) {
1689                 if (!indir)
1690                         return 0;
1691
1692                 key = rndis_dev->rss_key;
1693         }
1694
1695         return rndis_filter_set_rss_param(rndis_dev, key);
1696 }
1697
1698 /* Hyper-V RNDIS protocol does not have ring in the HW sense.
1699  * It does have pre-allocated receive area which is divided into sections.
1700  */
1701 static void __netvsc_get_ringparam(struct netvsc_device *nvdev,
1702                                    struct ethtool_ringparam *ring)
1703 {
1704         u32 max_buf_size;
1705
1706         ring->rx_pending = nvdev->recv_section_cnt;
1707         ring->tx_pending = nvdev->send_section_cnt;
1708
1709         if (nvdev->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
1710                 max_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
1711         else
1712                 max_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
1713
1714         ring->rx_max_pending = max_buf_size / nvdev->recv_section_size;
1715         ring->tx_max_pending = NETVSC_SEND_BUFFER_SIZE
1716                 / nvdev->send_section_size;
1717 }
1718
1719 static void netvsc_get_ringparam(struct net_device *ndev,
1720                                  struct ethtool_ringparam *ring)
1721 {
1722         struct net_device_context *ndevctx = netdev_priv(ndev);
1723         struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1724
1725         if (!nvdev)
1726                 return;
1727
1728         __netvsc_get_ringparam(nvdev, ring);
1729 }
1730
1731 static int netvsc_set_ringparam(struct net_device *ndev,
1732                                 struct ethtool_ringparam *ring)
1733 {
1734         struct net_device_context *ndevctx = netdev_priv(ndev);
1735         struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1736         struct netvsc_device_info *device_info;
1737         struct ethtool_ringparam orig;
1738         u32 new_tx, new_rx;
1739         int ret = 0;
1740
1741         if (!nvdev || nvdev->destroy)
1742                 return -ENODEV;
1743
1744         memset(&orig, 0, sizeof(orig));
1745         __netvsc_get_ringparam(nvdev, &orig);
1746
1747         new_tx = clamp_t(u32, ring->tx_pending,
1748                          NETVSC_MIN_TX_SECTIONS, orig.tx_max_pending);
1749         new_rx = clamp_t(u32, ring->rx_pending,
1750                          NETVSC_MIN_RX_SECTIONS, orig.rx_max_pending);
1751
1752         if (new_tx == orig.tx_pending &&
1753             new_rx == orig.rx_pending)
1754                 return 0;        /* no change */
1755
1756         device_info = netvsc_devinfo_get(nvdev);
1757
1758         if (!device_info)
1759                 return -ENOMEM;
1760
1761         device_info->send_sections = new_tx;
1762         device_info->recv_sections = new_rx;
1763
1764         ret = netvsc_detach(ndev, nvdev);
1765         if (ret)
1766                 goto out;
1767
1768         ret = netvsc_attach(ndev, device_info);
1769         if (ret) {
1770                 device_info->send_sections = orig.tx_pending;
1771                 device_info->recv_sections = orig.rx_pending;
1772
1773                 if (netvsc_attach(ndev, device_info))
1774                         netdev_err(ndev, "restoring ringparam failed");
1775         }
1776
1777 out:
1778         kfree(device_info);
1779         return ret;
1780 }
1781
1782 static int netvsc_set_features(struct net_device *ndev,
1783                                netdev_features_t features)
1784 {
1785         netdev_features_t change = features ^ ndev->features;
1786         struct net_device_context *ndevctx = netdev_priv(ndev);
1787         struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1788         struct ndis_offload_params offloads;
1789
1790         if (!nvdev || nvdev->destroy)
1791                 return -ENODEV;
1792
1793         if (!(change & NETIF_F_LRO))
1794                 return 0;
1795
1796         memset(&offloads, 0, sizeof(struct ndis_offload_params));
1797
1798         if (features & NETIF_F_LRO) {
1799                 offloads.rsc_ip_v4 = NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED;
1800                 offloads.rsc_ip_v6 = NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED;
1801         } else {
1802                 offloads.rsc_ip_v4 = NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED;
1803                 offloads.rsc_ip_v6 = NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED;
1804         }
1805
1806         return rndis_filter_set_offload_params(ndev, nvdev, &offloads);
1807 }
1808
1809 static u32 netvsc_get_msglevel(struct net_device *ndev)
1810 {
1811         struct net_device_context *ndev_ctx = netdev_priv(ndev);
1812
1813         return ndev_ctx->msg_enable;
1814 }
1815
1816 static void netvsc_set_msglevel(struct net_device *ndev, u32 val)
1817 {
1818         struct net_device_context *ndev_ctx = netdev_priv(ndev);
1819
1820         ndev_ctx->msg_enable = val;
1821 }
1822
1823 static const struct ethtool_ops ethtool_ops = {
1824         .get_drvinfo    = netvsc_get_drvinfo,
1825         .get_msglevel   = netvsc_get_msglevel,
1826         .set_msglevel   = netvsc_set_msglevel,
1827         .get_link       = ethtool_op_get_link,
1828         .get_ethtool_stats = netvsc_get_ethtool_stats,
1829         .get_sset_count = netvsc_get_sset_count,
1830         .get_strings    = netvsc_get_strings,
1831         .get_channels   = netvsc_get_channels,
1832         .set_channels   = netvsc_set_channels,
1833         .get_ts_info    = ethtool_op_get_ts_info,
1834         .get_rxnfc      = netvsc_get_rxnfc,
1835         .set_rxnfc      = netvsc_set_rxnfc,
1836         .get_rxfh_key_size = netvsc_get_rxfh_key_size,
1837         .get_rxfh_indir_size = netvsc_rss_indir_size,
1838         .get_rxfh       = netvsc_get_rxfh,
1839         .set_rxfh       = netvsc_set_rxfh,
1840         .get_link_ksettings = netvsc_get_link_ksettings,
1841         .set_link_ksettings = netvsc_set_link_ksettings,
1842         .get_ringparam  = netvsc_get_ringparam,
1843         .set_ringparam  = netvsc_set_ringparam,
1844 };
1845
1846 static const struct net_device_ops device_ops = {
1847         .ndo_open =                     netvsc_open,
1848         .ndo_stop =                     netvsc_close,
1849         .ndo_start_xmit =               netvsc_start_xmit,
1850         .ndo_change_rx_flags =          netvsc_change_rx_flags,
1851         .ndo_set_rx_mode =              netvsc_set_rx_mode,
1852         .ndo_set_features =             netvsc_set_features,
1853         .ndo_change_mtu =               netvsc_change_mtu,
1854         .ndo_validate_addr =            eth_validate_addr,
1855         .ndo_set_mac_address =          netvsc_set_mac_addr,
1856         .ndo_select_queue =             netvsc_select_queue,
1857         .ndo_get_stats64 =              netvsc_get_stats64,
1858 };
1859
1860 /*
1861  * Handle link status changes. For RNDIS_STATUS_NETWORK_CHANGE emulate link
1862  * down/up sequence. In case of RNDIS_STATUS_MEDIA_CONNECT when carrier is
1863  * present send GARP packet to network peers with netif_notify_peers().
1864  */
1865 static void netvsc_link_change(struct work_struct *w)
1866 {
1867         struct net_device_context *ndev_ctx =
1868                 container_of(w, struct net_device_context, dwork.work);
1869         struct hv_device *device_obj = ndev_ctx->device_ctx;
1870         struct net_device *net = hv_get_drvdata(device_obj);
1871         struct netvsc_device *net_device;
1872         struct rndis_device *rdev;
1873         struct netvsc_reconfig *event = NULL;
1874         bool notify = false, reschedule = false;
1875         unsigned long flags, next_reconfig, delay;
1876
1877         /* if changes are happening, comeback later */
1878         if (!rtnl_trylock()) {
1879                 schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
1880                 return;
1881         }
1882
1883         net_device = rtnl_dereference(ndev_ctx->nvdev);
1884         if (!net_device)
1885                 goto out_unlock;
1886
1887         rdev = net_device->extension;
1888
1889         next_reconfig = ndev_ctx->last_reconfig + LINKCHANGE_INT;
1890         if (time_is_after_jiffies(next_reconfig)) {
1891                 /* link_watch only sends one notification with current state
1892                  * per second, avoid doing reconfig more frequently. Handle
1893                  * wrap around.
1894                  */
1895                 delay = next_reconfig - jiffies;
1896                 delay = delay < LINKCHANGE_INT ? delay : LINKCHANGE_INT;
1897                 schedule_delayed_work(&ndev_ctx->dwork, delay);
1898                 goto out_unlock;
1899         }
1900         ndev_ctx->last_reconfig = jiffies;
1901
1902         spin_lock_irqsave(&ndev_ctx->lock, flags);
1903         if (!list_empty(&ndev_ctx->reconfig_events)) {
1904                 event = list_first_entry(&ndev_ctx->reconfig_events,
1905                                          struct netvsc_reconfig, list);
1906                 list_del(&event->list);
1907                 reschedule = !list_empty(&ndev_ctx->reconfig_events);
1908         }
1909         spin_unlock_irqrestore(&ndev_ctx->lock, flags);
1910
1911         if (!event)
1912                 goto out_unlock;
1913
1914         switch (event->event) {
1915                 /* Only the following events are possible due to the check in
1916                  * netvsc_linkstatus_callback()
1917                  */
1918         case RNDIS_STATUS_MEDIA_CONNECT:
1919                 if (rdev->link_state) {
1920                         rdev->link_state = false;
1921                         netif_carrier_on(net);
1922                         netvsc_tx_enable(net_device, net);
1923                 } else {
1924                         notify = true;
1925                 }
1926                 kfree(event);
1927                 break;
1928         case RNDIS_STATUS_MEDIA_DISCONNECT:
1929                 if (!rdev->link_state) {
1930                         rdev->link_state = true;
1931                         netif_carrier_off(net);
1932                         netvsc_tx_disable(net_device, net);
1933                 }
1934                 kfree(event);
1935                 break;
1936         case RNDIS_STATUS_NETWORK_CHANGE:
1937                 /* Only makes sense if carrier is present */
1938                 if (!rdev->link_state) {
1939                         rdev->link_state = true;
1940                         netif_carrier_off(net);
1941                         netvsc_tx_disable(net_device, net);
1942                         event->event = RNDIS_STATUS_MEDIA_CONNECT;
1943                         spin_lock_irqsave(&ndev_ctx->lock, flags);
1944                         list_add(&event->list, &ndev_ctx->reconfig_events);
1945                         spin_unlock_irqrestore(&ndev_ctx->lock, flags);
1946                         reschedule = true;
1947                 }
1948                 break;
1949         }
1950
1951         rtnl_unlock();
1952
1953         if (notify)
1954                 netdev_notify_peers(net);
1955
1956         /* link_watch only sends one notification with current state per
1957          * second, handle next reconfig event in 2 seconds.
1958          */
1959         if (reschedule)
1960                 schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
1961
1962         return;
1963
1964 out_unlock:
1965         rtnl_unlock();
1966 }
1967
1968 static struct net_device *get_netvsc_byref(struct net_device *vf_netdev)
1969 {
1970         struct net_device_context *net_device_ctx;
1971         struct net_device *dev;
1972
1973         dev = netdev_master_upper_dev_get(vf_netdev);
1974         if (!dev || dev->netdev_ops != &device_ops)
1975                 return NULL;    /* not a netvsc device */
1976
1977         net_device_ctx = netdev_priv(dev);
1978         if (!rtnl_dereference(net_device_ctx->nvdev))
1979                 return NULL;    /* device is removed */
1980
1981         return dev;
1982 }
1983
1984 /* Called when VF is injecting data into network stack.
1985  * Change the associated network device from VF to netvsc.
1986  * note: already called with rcu_read_lock
1987  */
1988 static rx_handler_result_t netvsc_vf_handle_frame(struct sk_buff **pskb)
1989 {
1990         struct sk_buff *skb = *pskb;
1991         struct net_device *ndev = rcu_dereference(skb->dev->rx_handler_data);
1992         struct net_device_context *ndev_ctx = netdev_priv(ndev);
1993         struct netvsc_vf_pcpu_stats *pcpu_stats
1994                  = this_cpu_ptr(ndev_ctx->vf_stats);
1995
1996         skb = skb_share_check(skb, GFP_ATOMIC);
1997         if (unlikely(!skb))
1998                 return RX_HANDLER_CONSUMED;
1999
2000         *pskb = skb;
2001
2002         skb->dev = ndev;
2003
2004         u64_stats_update_begin(&pcpu_stats->syncp);
2005         pcpu_stats->rx_packets++;
2006         pcpu_stats->rx_bytes += skb->len;
2007         u64_stats_update_end(&pcpu_stats->syncp);
2008
2009         return RX_HANDLER_ANOTHER;
2010 }
2011
2012 static int netvsc_vf_join(struct net_device *vf_netdev,
2013                           struct net_device *ndev)
2014 {
2015         struct net_device_context *ndev_ctx = netdev_priv(ndev);
2016         int ret;
2017
2018         ret = netdev_rx_handler_register(vf_netdev,
2019                                          netvsc_vf_handle_frame, ndev);
2020         if (ret != 0) {
2021                 netdev_err(vf_netdev,
2022                            "can not register netvsc VF receive handler (err = %d)\n",
2023                            ret);
2024                 goto rx_handler_failed;
2025         }
2026
2027         ret = netdev_master_upper_dev_link(vf_netdev, ndev,
2028                                            NULL, NULL, NULL);
2029         if (ret != 0) {
2030                 netdev_err(vf_netdev,
2031                            "can not set master device %s (err = %d)\n",
2032                            ndev->name, ret);
2033                 goto upper_link_failed;
2034         }
2035
2036         /* set slave flag before open to prevent IPv6 addrconf */
2037         vf_netdev->flags |= IFF_SLAVE;
2038
2039         schedule_delayed_work(&ndev_ctx->vf_takeover, VF_TAKEOVER_INT);
2040
2041         call_netdevice_notifiers(NETDEV_JOIN, vf_netdev);
2042
2043         netdev_info(vf_netdev, "joined to %s\n", ndev->name);
2044         return 0;
2045
2046 upper_link_failed:
2047         netdev_rx_handler_unregister(vf_netdev);
2048 rx_handler_failed:
2049         return ret;
2050 }
2051
2052 static void __netvsc_vf_setup(struct net_device *ndev,
2053                               struct net_device *vf_netdev)
2054 {
2055         int ret;
2056
2057         /* Align MTU of VF with master */
2058         ret = dev_set_mtu(vf_netdev, ndev->mtu);
2059         if (ret)
2060                 netdev_warn(vf_netdev,
2061                             "unable to change mtu to %u\n", ndev->mtu);
2062
2063         /* set multicast etc flags on VF */
2064         dev_change_flags(vf_netdev, ndev->flags | IFF_SLAVE, NULL);
2065
2066         /* sync address list from ndev to VF */
2067         netif_addr_lock_bh(ndev);
2068         dev_uc_sync(vf_netdev, ndev);
2069         dev_mc_sync(vf_netdev, ndev);
2070         netif_addr_unlock_bh(ndev);
2071
2072         if (netif_running(ndev)) {
2073                 ret = dev_open(vf_netdev, NULL);
2074                 if (ret)
2075                         netdev_warn(vf_netdev,
2076                                     "unable to open: %d\n", ret);
2077         }
2078 }
2079
2080 /* Setup VF as slave of the synthetic device.
2081  * Runs in workqueue to avoid recursion in netlink callbacks.
2082  */
2083 static void netvsc_vf_setup(struct work_struct *w)
2084 {
2085         struct net_device_context *ndev_ctx
2086                 = container_of(w, struct net_device_context, vf_takeover.work);
2087         struct net_device *ndev = hv_get_drvdata(ndev_ctx->device_ctx);
2088         struct net_device *vf_netdev;
2089
2090         if (!rtnl_trylock()) {
2091                 schedule_delayed_work(&ndev_ctx->vf_takeover, 0);
2092                 return;
2093         }
2094
2095         vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
2096         if (vf_netdev)
2097                 __netvsc_vf_setup(ndev, vf_netdev);
2098
2099         rtnl_unlock();
2100 }
2101
2102 /* Find netvsc by VF serial number.
2103  * The PCI hyperv controller records the serial number as the slot kobj name.
2104  */
2105 static struct net_device *get_netvsc_byslot(const struct net_device *vf_netdev)
2106 {
2107         struct device *parent = vf_netdev->dev.parent;
2108         struct net_device_context *ndev_ctx;
2109         struct pci_dev *pdev;
2110         u32 serial;
2111
2112         if (!parent || !dev_is_pci(parent))
2113                 return NULL; /* not a PCI device */
2114
2115         pdev = to_pci_dev(parent);
2116         if (!pdev->slot) {
2117                 netdev_notice(vf_netdev, "no PCI slot information\n");
2118                 return NULL;
2119         }
2120
2121         if (kstrtou32(pci_slot_name(pdev->slot), 10, &serial)) {
2122                 netdev_notice(vf_netdev, "Invalid vf serial:%s\n",
2123                               pci_slot_name(pdev->slot));
2124                 return NULL;
2125         }
2126
2127         list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) {
2128                 if (!ndev_ctx->vf_alloc)
2129                         continue;
2130
2131                 if (ndev_ctx->vf_serial == serial)
2132                         return hv_get_drvdata(ndev_ctx->device_ctx);
2133         }
2134
2135         netdev_notice(vf_netdev,
2136                       "no netdev found for vf serial:%u\n", serial);
2137         return NULL;
2138 }
2139
2140 static int netvsc_register_vf(struct net_device *vf_netdev)
2141 {
2142         struct net_device_context *net_device_ctx;
2143         struct netvsc_device *netvsc_dev;
2144         struct net_device *ndev;
2145         int ret;
2146
2147         if (vf_netdev->addr_len != ETH_ALEN)
2148                 return NOTIFY_DONE;
2149
2150         ndev = get_netvsc_byslot(vf_netdev);
2151         if (!ndev)
2152                 return NOTIFY_DONE;
2153
2154         net_device_ctx = netdev_priv(ndev);
2155         netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
2156         if (!netvsc_dev || rtnl_dereference(net_device_ctx->vf_netdev))
2157                 return NOTIFY_DONE;
2158
2159         /* if synthetic interface is a different namespace,
2160          * then move the VF to that namespace; join will be
2161          * done again in that context.
2162          */
2163         if (!net_eq(dev_net(ndev), dev_net(vf_netdev))) {
2164                 ret = dev_change_net_namespace(vf_netdev,
2165                                                dev_net(ndev), "eth%d");
2166                 if (ret)
2167                         netdev_err(vf_netdev,
2168                                    "could not move to same namespace as %s: %d\n",
2169                                    ndev->name, ret);
2170                 else
2171                         netdev_info(vf_netdev,
2172                                     "VF moved to namespace with: %s\n",
2173                                     ndev->name);
2174                 return NOTIFY_DONE;
2175         }
2176
2177         netdev_info(ndev, "VF registering: %s\n", vf_netdev->name);
2178
2179         if (netvsc_vf_join(vf_netdev, ndev) != 0)
2180                 return NOTIFY_DONE;
2181
2182         dev_hold(vf_netdev);
2183         rcu_assign_pointer(net_device_ctx->vf_netdev, vf_netdev);
2184         return NOTIFY_OK;
2185 }
2186
2187 /* VF up/down change detected, schedule to change data path */
2188 static int netvsc_vf_changed(struct net_device *vf_netdev)
2189 {
2190         struct net_device_context *net_device_ctx;
2191         struct netvsc_device *netvsc_dev;
2192         struct net_device *ndev;
2193         bool vf_is_up = netif_running(vf_netdev);
2194
2195         ndev = get_netvsc_byref(vf_netdev);
2196         if (!ndev)
2197                 return NOTIFY_DONE;
2198
2199         net_device_ctx = netdev_priv(ndev);
2200         netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
2201         if (!netvsc_dev)
2202                 return NOTIFY_DONE;
2203
2204         netvsc_switch_datapath(ndev, vf_is_up);
2205         netdev_info(ndev, "Data path switched %s VF: %s\n",
2206                     vf_is_up ? "to" : "from", vf_netdev->name);
2207
2208         return NOTIFY_OK;
2209 }
2210
2211 static int netvsc_unregister_vf(struct net_device *vf_netdev)
2212 {
2213         struct net_device *ndev;
2214         struct net_device_context *net_device_ctx;
2215
2216         ndev = get_netvsc_byref(vf_netdev);
2217         if (!ndev)
2218                 return NOTIFY_DONE;
2219
2220         net_device_ctx = netdev_priv(ndev);
2221         cancel_delayed_work_sync(&net_device_ctx->vf_takeover);
2222
2223         netdev_info(ndev, "VF unregistering: %s\n", vf_netdev->name);
2224
2225         netdev_rx_handler_unregister(vf_netdev);
2226         netdev_upper_dev_unlink(vf_netdev, ndev);
2227         RCU_INIT_POINTER(net_device_ctx->vf_netdev, NULL);
2228         dev_put(vf_netdev);
2229
2230         return NOTIFY_OK;
2231 }
2232
2233 static int netvsc_probe(struct hv_device *dev,
2234                         const struct hv_vmbus_device_id *dev_id)
2235 {
2236         struct net_device *net = NULL;
2237         struct net_device_context *net_device_ctx;
2238         struct netvsc_device_info *device_info = NULL;
2239         struct netvsc_device *nvdev;
2240         int ret = -ENOMEM;
2241
2242         net = alloc_etherdev_mq(sizeof(struct net_device_context),
2243                                 VRSS_CHANNEL_MAX);
2244         if (!net)
2245                 goto no_net;
2246
2247         netif_carrier_off(net);
2248
2249         netvsc_init_settings(net);
2250
2251         net_device_ctx = netdev_priv(net);
2252         net_device_ctx->device_ctx = dev;
2253         net_device_ctx->msg_enable = netif_msg_init(debug, default_msg);
2254         if (netif_msg_probe(net_device_ctx))
2255                 netdev_dbg(net, "netvsc msg_enable: %d\n",
2256                            net_device_ctx->msg_enable);
2257
2258         hv_set_drvdata(dev, net);
2259
2260         INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
2261
2262         spin_lock_init(&net_device_ctx->lock);
2263         INIT_LIST_HEAD(&net_device_ctx->reconfig_events);
2264         INIT_DELAYED_WORK(&net_device_ctx->vf_takeover, netvsc_vf_setup);
2265
2266         net_device_ctx->vf_stats
2267                 = netdev_alloc_pcpu_stats(struct netvsc_vf_pcpu_stats);
2268         if (!net_device_ctx->vf_stats)
2269                 goto no_stats;
2270
2271         net->netdev_ops = &device_ops;
2272         net->ethtool_ops = &ethtool_ops;
2273         SET_NETDEV_DEV(net, &dev->device);
2274
2275         /* We always need headroom for rndis header */
2276         net->needed_headroom = RNDIS_AND_PPI_SIZE;
2277
2278         /* Initialize the number of queues to be 1, we may change it if more
2279          * channels are offered later.
2280          */
2281         netif_set_real_num_tx_queues(net, 1);
2282         netif_set_real_num_rx_queues(net, 1);
2283
2284         /* Notify the netvsc driver of the new device */
2285         device_info = netvsc_devinfo_get(NULL);
2286
2287         if (!device_info) {
2288                 ret = -ENOMEM;
2289                 goto devinfo_failed;
2290         }
2291
2292         nvdev = rndis_filter_device_add(dev, device_info);
2293         if (IS_ERR(nvdev)) {
2294                 ret = PTR_ERR(nvdev);
2295                 netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
2296                 goto rndis_failed;
2297         }
2298
2299         memcpy(net->dev_addr, device_info->mac_adr, ETH_ALEN);
2300
2301         /* We must get rtnl lock before scheduling nvdev->subchan_work,
2302          * otherwise netvsc_subchan_work() can get rtnl lock first and wait
2303          * all subchannels to show up, but that may not happen because
2304          * netvsc_probe() can't get rtnl lock and as a result vmbus_onoffer()
2305          * -> ... -> device_add() -> ... -> __device_attach() can't get
2306          * the device lock, so all the subchannels can't be processed --
2307          * finally netvsc_subchan_work() hangs forever.
2308          */
2309         rtnl_lock();
2310
2311         if (nvdev->num_chn > 1)
2312                 schedule_work(&nvdev->subchan_work);
2313
2314         /* hw_features computed in rndis_netdev_set_hwcaps() */
2315         net->features = net->hw_features |
2316                 NETIF_F_HIGHDMA | NETIF_F_SG |
2317                 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX;
2318         net->vlan_features = net->features;
2319
2320         netdev_lockdep_set_classes(net);
2321
2322         /* MTU range: 68 - 1500 or 65521 */
2323         net->min_mtu = NETVSC_MTU_MIN;
2324         if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
2325                 net->max_mtu = NETVSC_MTU - ETH_HLEN;
2326         else
2327                 net->max_mtu = ETH_DATA_LEN;
2328
2329         ret = register_netdevice(net);
2330         if (ret != 0) {
2331                 pr_err("Unable to register netdev.\n");
2332                 goto register_failed;
2333         }
2334
2335         list_add(&net_device_ctx->list, &netvsc_dev_list);
2336         rtnl_unlock();
2337
2338         kfree(device_info);
2339         return 0;
2340
2341 register_failed:
2342         rtnl_unlock();
2343         rndis_filter_device_remove(dev, nvdev);
2344 rndis_failed:
2345         kfree(device_info);
2346 devinfo_failed:
2347         free_percpu(net_device_ctx->vf_stats);
2348 no_stats:
2349         hv_set_drvdata(dev, NULL);
2350         free_netdev(net);
2351 no_net:
2352         return ret;
2353 }
2354
2355 static int netvsc_remove(struct hv_device *dev)
2356 {
2357         struct net_device_context *ndev_ctx;
2358         struct net_device *vf_netdev, *net;
2359         struct netvsc_device *nvdev;
2360
2361         net = hv_get_drvdata(dev);
2362         if (net == NULL) {
2363                 dev_err(&dev->device, "No net device to remove\n");
2364                 return 0;
2365         }
2366
2367         ndev_ctx = netdev_priv(net);
2368
2369         cancel_delayed_work_sync(&ndev_ctx->dwork);
2370
2371         rtnl_lock();
2372         nvdev = rtnl_dereference(ndev_ctx->nvdev);
2373         if (nvdev)
2374                 cancel_work_sync(&nvdev->subchan_work);
2375
2376         /*
2377          * Call to the vsc driver to let it know that the device is being
2378          * removed. Also blocks mtu and channel changes.
2379          */
2380         vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
2381         if (vf_netdev)
2382                 netvsc_unregister_vf(vf_netdev);
2383
2384         if (nvdev)
2385                 rndis_filter_device_remove(dev, nvdev);
2386
2387         unregister_netdevice(net);
2388         list_del(&ndev_ctx->list);
2389
2390         rtnl_unlock();
2391
2392         hv_set_drvdata(dev, NULL);
2393
2394         free_percpu(ndev_ctx->vf_stats);
2395         free_netdev(net);
2396         return 0;
2397 }
2398
2399 static const struct hv_vmbus_device_id id_table[] = {
2400         /* Network guid */
2401         { HV_NIC_GUID, },
2402         { },
2403 };
2404
2405 MODULE_DEVICE_TABLE(vmbus, id_table);
2406
2407 /* The one and only one */
2408 static struct  hv_driver netvsc_drv = {
2409         .name = KBUILD_MODNAME,
2410         .id_table = id_table,
2411         .probe = netvsc_probe,
2412         .remove = netvsc_remove,
2413         .driver = {
2414                 .probe_type = PROBE_FORCE_SYNCHRONOUS,
2415         },
2416 };
2417
2418 /*
2419  * On Hyper-V, every VF interface is matched with a corresponding
2420  * synthetic interface. The synthetic interface is presented first
2421  * to the guest. When the corresponding VF instance is registered,
2422  * we will take care of switching the data path.
2423  */
2424 static int netvsc_netdev_event(struct notifier_block *this,
2425                                unsigned long event, void *ptr)
2426 {
2427         struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2428
2429         /* Skip our own events */
2430         if (event_dev->netdev_ops == &device_ops)
2431                 return NOTIFY_DONE;
2432
2433         /* Avoid non-Ethernet type devices */
2434         if (event_dev->type != ARPHRD_ETHER)
2435                 return NOTIFY_DONE;
2436
2437         /* Avoid Vlan dev with same MAC registering as VF */
2438         if (is_vlan_dev(event_dev))
2439                 return NOTIFY_DONE;
2440
2441         /* Avoid Bonding master dev with same MAC registering as VF */
2442         if ((event_dev->priv_flags & IFF_BONDING) &&
2443             (event_dev->flags & IFF_MASTER))
2444                 return NOTIFY_DONE;
2445
2446         switch (event) {
2447         case NETDEV_REGISTER:
2448                 return netvsc_register_vf(event_dev);
2449         case NETDEV_UNREGISTER:
2450                 return netvsc_unregister_vf(event_dev);
2451         case NETDEV_UP:
2452         case NETDEV_DOWN:
2453                 return netvsc_vf_changed(event_dev);
2454         default:
2455                 return NOTIFY_DONE;
2456         }
2457 }
2458
2459 static struct notifier_block netvsc_netdev_notifier = {
2460         .notifier_call = netvsc_netdev_event,
2461 };
2462
2463 static void __exit netvsc_drv_exit(void)
2464 {
2465         unregister_netdevice_notifier(&netvsc_netdev_notifier);
2466         vmbus_driver_unregister(&netvsc_drv);
2467 }
2468
2469 static int __init netvsc_drv_init(void)
2470 {
2471         int ret;
2472
2473         if (ring_size < RING_SIZE_MIN) {
2474                 ring_size = RING_SIZE_MIN;
2475                 pr_info("Increased ring_size to %u (min allowed)\n",
2476                         ring_size);
2477         }
2478         netvsc_ring_bytes = ring_size * PAGE_SIZE;
2479
2480         ret = vmbus_driver_register(&netvsc_drv);
2481         if (ret)
2482                 return ret;
2483
2484         register_netdevice_notifier(&netvsc_netdev_notifier);
2485         return 0;
2486 }
2487
2488 MODULE_LICENSE("GPL");
2489 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
2490
2491 module_init(netvsc_drv_init);
2492 module_exit(netvsc_drv_exit);