drivers/net/hyperv/netvsc_drv.c

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