drivers/net/hyperv/netvsc.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/kernel.h>
  23 #include <linux/sched.h>
  24 #include <linux/wait.h>
  25 #include <linux/mm.h>
  26 #include <linux/delay.h>
  27 #include <linux/io.h>
  28 #include <linux/slab.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/if_ether.h>
  31 #include <linux/vmalloc.h>
  32 #include <linux/rtnetlink.h>
  33 #include <linux/prefetch.h>
  34
  35 #include <asm/sync_bitops.h>
  36
  37 #include "hyperv_net.h"
  38 #include "netvsc_trace.h"
  39
  40 /*
  41  * Switch the data path from the synthetic interface to the VF
  42  * interface.
  43  */
  44 void netvsc_switch_datapath(struct net_device *ndev, bool vf)
  45 {
  46         struct net_device_context *net_device_ctx = netdev_priv(ndev);
  47         struct hv_device *dev = net_device_ctx->device_ctx;
  48         struct netvsc_device *nv_dev = rtnl_dereference(net_device_ctx->nvdev);
  49         struct nvsp_message *init_pkt = &nv_dev->channel_init_pkt;
  50
  51         memset(init_pkt, 0, sizeof(struct nvsp_message));
  52         init_pkt->hdr.msg_type = NVSP_MSG4_TYPE_SWITCH_DATA_PATH;
  53         if (vf)
  54                 init_pkt->msg.v4_msg.active_dp.active_datapath =
  55                         NVSP_DATAPATH_VF;
  56         else
  57                 init_pkt->msg.v4_msg.active_dp.active_datapath =
  58                         NVSP_DATAPATH_SYNTHETIC;
  59
  60         trace_nvsp_send(ndev, init_pkt);
  61
  62         vmbus_sendpacket(dev->channel, init_pkt,
  63                                sizeof(struct nvsp_message),
  64                                (unsigned long)init_pkt,
  65                                VM_PKT_DATA_INBAND, 0);
  66 }
  67
  68 /* Worker to setup sub channels on initial setup
  69  * Initial hotplug event occurs in softirq context
  70  * and can't wait for channels.
  71  */
  72 static void netvsc_subchan_work(struct work_struct *w)
  73 {
  74         struct netvsc_device *nvdev =
  75                 container_of(w, struct netvsc_device, subchan_work);
  76         struct rndis_device *rdev;
  77         int i, ret;
  78
  79         /* Avoid deadlock with device removal already under RTNL */
  80         if (!rtnl_trylock()) {
  81                 schedule_work(w);
  82                 return;
  83         }
  84
  85         rdev = nvdev->extension;
  86         if (rdev) {
  87                 ret = rndis_set_subchannel(rdev->ndev, nvdev);
  88                 if (ret == 0) {
  89                         netif_device_attach(rdev->ndev);
  90                 } else {
  91                         /* fallback to only primary channel */
  92                         for (i = 1; i < nvdev->num_chn; i++)
  93                                 netif_napi_del(&nvdev->chan_table[i].napi);
  94
  95                         nvdev->max_chn = 1;
  96                         nvdev->num_chn = 1;
  97                 }
  98         }
  99
 100         rtnl_unlock();
 101 }
 102
 103 static struct netvsc_device *alloc_net_device(void)
 104 {
 105         struct netvsc_device *net_device;
 106
 107         net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
 108         if (!net_device)
 109                 return NULL;
 110
 111         init_waitqueue_head(&net_device->wait_drain);
 112         net_device->destroy = false;
 113
 114         net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
 115         net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
 116
 117         init_completion(&net_device->channel_init_wait);
 118         init_waitqueue_head(&net_device->subchan_open);
 119         INIT_WORK(&net_device->subchan_work, netvsc_subchan_work);
 120
 121         return net_device;
 122 }
 123
 124 static void free_netvsc_device(struct rcu_head *head)
 125 {
 126         struct netvsc_device *nvdev
 127                 = container_of(head, struct netvsc_device, rcu);
 128         int i;
 129
 130         kfree(nvdev->extension);
 131         vfree(nvdev->recv_buf);
 132         vfree(nvdev->send_buf);
 133         kfree(nvdev->send_section_map);
 134
 135         for (i = 0; i < VRSS_CHANNEL_MAX; i++)
 136                 vfree(nvdev->chan_table[i].mrc.slots);
 137
 138         kfree(nvdev);
 139 }
 140
 141 static void free_netvsc_device_rcu(struct netvsc_device *nvdev)
 142 {
 143         call_rcu(&nvdev->rcu, free_netvsc_device);
 144 }
 145
 146 static void netvsc_revoke_recv_buf(struct hv_device *device,
 147                                    struct netvsc_device *net_device,
 148                                    struct net_device *ndev)
 149 {
 150         struct nvsp_message *revoke_packet;
 151         int ret;
 152
 153         /*
 154          * If we got a section count, it means we received a
 155          * SendReceiveBufferComplete msg (ie sent
 156          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 157          * to send a revoke msg here
 158          */
 159         if (net_device->recv_section_cnt) {
 160                 /* Send the revoke receive buffer */
 161                 revoke_packet = &net_device->revoke_packet;
 162                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 163
 164                 revoke_packet->hdr.msg_type =
 165                         NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
 166                 revoke_packet->msg.v1_msg.
 167                 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 168
 169                 trace_nvsp_send(ndev, revoke_packet);
 170
 171                 ret = vmbus_sendpacket(device->channel,
 172                                        revoke_packet,
 173                                        sizeof(struct nvsp_message),
 174                                        (unsigned long)revoke_packet,
 175                                        VM_PKT_DATA_INBAND, 0);
 176                 /* If the failure is because the channel is rescinded;
 177                  * ignore the failure since we cannot send on a rescinded
 178                  * channel. This would allow us to properly cleanup
 179                  * even when the channel is rescinded.
 180                  */
 181                 if (device->channel->rescind)
 182                         ret = 0;
 183                 /*
 184                  * If we failed here, we might as well return and
 185                  * have a leak rather than continue and a bugchk
 186                  */
 187                 if (ret != 0) {
 188                         netdev_err(ndev, "unable to send "
 189                                 "revoke receive buffer to netvsp\n");
 190                         return;
 191                 }
 192                 net_device->recv_section_cnt = 0;
 193         }
 194 }
 195
 196 static void netvsc_revoke_send_buf(struct hv_device *device,
 197                                    struct netvsc_device *net_device,
 198                                    struct net_device *ndev)
 199 {
 200         struct nvsp_message *revoke_packet;
 201         int ret;
 202
 203         /* Deal with the send buffer we may have setup.
 204          * If we got a  send section size, it means we received a
 205          * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
 206          * NVSP_MSG1_TYPE_SEND_SEND_BUF msg) therefore, we need
 207          * to send a revoke msg here
 208          */
 209         if (net_device->send_section_cnt) {
 210                 /* Send the revoke receive buffer */
 211                 revoke_packet = &net_device->revoke_packet;
 212                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 213
 214                 revoke_packet->hdr.msg_type =
 215                         NVSP_MSG1_TYPE_REVOKE_SEND_BUF;
 216                 revoke_packet->msg.v1_msg.revoke_send_buf.id =
 217                         NETVSC_SEND_BUFFER_ID;
 218
 219                 trace_nvsp_send(ndev, revoke_packet);
 220
 221                 ret = vmbus_sendpacket(device->channel,
 222                                        revoke_packet,
 223                                        sizeof(struct nvsp_message),
 224                                        (unsigned long)revoke_packet,
 225                                        VM_PKT_DATA_INBAND, 0);
 226
 227                 /* If the failure is because the channel is rescinded;
 228                  * ignore the failure since we cannot send on a rescinded
 229                  * channel. This would allow us to properly cleanup
 230                  * even when the channel is rescinded.
 231                  */
 232                 if (device->channel->rescind)
 233                         ret = 0;
 234
 235                 /* If we failed here, we might as well return and
 236                  * have a leak rather than continue and a bugchk
 237                  */
 238                 if (ret != 0) {
 239                         netdev_err(ndev, "unable to send "
 240                                    "revoke send buffer to netvsp\n");
 241                         return;
 242                 }
 243                 net_device->send_section_cnt = 0;
 244         }
 245 }
 246
 247 static void netvsc_teardown_recv_gpadl(struct hv_device *device,
 248                                        struct netvsc_device *net_device,
 249                                        struct net_device *ndev)
 250 {
 251         int ret;
 252
 253         if (net_device->recv_buf_gpadl_handle) {
 254                 ret = vmbus_teardown_gpadl(device->channel,
 255                                            net_device->recv_buf_gpadl_handle);
 256
 257                 /* If we failed here, we might as well return and have a leak
 258                  * rather than continue and a bugchk
 259                  */
 260                 if (ret != 0) {
 261                         netdev_err(ndev,
 262                                    "unable to teardown receive buffer's gpadl\n");
 263                         return;
 264                 }
 265                 net_device->recv_buf_gpadl_handle = 0;
 266         }
 267 }
 268
 269 static void netvsc_teardown_send_gpadl(struct hv_device *device,
 270                                        struct netvsc_device *net_device,
 271                                        struct net_device *ndev)
 272 {
 273         int ret;
 274
 275         if (net_device->send_buf_gpadl_handle) {
 276                 ret = vmbus_teardown_gpadl(device->channel,
 277                                            net_device->send_buf_gpadl_handle);
 278
 279                 /* If we failed here, we might as well return and have a leak
 280                  * rather than continue and a bugchk
 281                  */
 282                 if (ret != 0) {
 283                         netdev_err(ndev,
 284                                    "unable to teardown send buffer's gpadl\n");
 285                         return;
 286                 }
 287                 net_device->send_buf_gpadl_handle = 0;
 288         }
 289 }
 290
 291 int netvsc_alloc_recv_comp_ring(struct netvsc_device *net_device, u32 q_idx)
 292 {
 293         struct netvsc_channel *nvchan = &net_device->chan_table[q_idx];
 294         int node = cpu_to_node(nvchan->channel->target_cpu);
 295         size_t size;
 296
 297         size = net_device->recv_completion_cnt * sizeof(struct recv_comp_data);
 298         nvchan->mrc.slots = vzalloc_node(size, node);
 299         if (!nvchan->mrc.slots)
 300                 nvchan->mrc.slots = vzalloc(size);
 301
 302         return nvchan->mrc.slots ? 0 : -ENOMEM;
 303 }
 304
 305 static int netvsc_init_buf(struct hv_device *device,
 306                            struct netvsc_device *net_device,
 307                            const struct netvsc_device_info *device_info)
 308 {
 309         struct nvsp_1_message_send_receive_buffer_complete *resp;
 310         struct net_device *ndev = hv_get_drvdata(device);
 311         struct nvsp_message *init_packet;
 312         unsigned int buf_size;
 313         size_t map_words;
 314         int ret = 0;
 315
 316         /* Get receive buffer area. */
 317         buf_size = device_info->recv_sections * device_info->recv_section_size;
 318         buf_size = roundup(buf_size, PAGE_SIZE);
 319
 320         /* Legacy hosts only allow smaller receive buffer */
 321         if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
 322                 buf_size = min_t(unsigned int, buf_size,
 323                                  NETVSC_RECEIVE_BUFFER_SIZE_LEGACY);
 324
 325         net_device->recv_buf = vzalloc(buf_size);
 326         if (!net_device->recv_buf) {
 327                 netdev_err(ndev,
 328                            "unable to allocate receive buffer of size %u\n",
 329                            buf_size);
 330                 ret = -ENOMEM;
 331                 goto cleanup;
 332         }
 333
 334         net_device->recv_buf_size = buf_size;
 335
 336         /*
 337          * Establish the gpadl handle for this buffer on this
 338          * channel.  Note: This call uses the vmbus connection rather
 339          * than the channel to establish the gpadl handle.
 340          */
 341         ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
 342                                     buf_size,
 343                                     &net_device->recv_buf_gpadl_handle);
 344         if (ret != 0) {
 345                 netdev_err(ndev,
 346                         "unable to establish receive buffer's gpadl\n");
 347                 goto cleanup;
 348         }
 349
 350         /* Notify the NetVsp of the gpadl handle */
 351         init_packet = &net_device->channel_init_pkt;
 352         memset(init_packet, 0, sizeof(struct nvsp_message));
 353         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 354         init_packet->msg.v1_msg.send_recv_buf.
 355                 gpadl_handle = net_device->recv_buf_gpadl_handle;
 356         init_packet->msg.v1_msg.
 357                 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 358
 359         trace_nvsp_send(ndev, init_packet);
 360
 361         /* Send the gpadl notification request */
 362         ret = vmbus_sendpacket(device->channel, init_packet,
 363                                sizeof(struct nvsp_message),
 364                                (unsigned long)init_packet,
 365                                VM_PKT_DATA_INBAND,
 366                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 367         if (ret != 0) {
 368                 netdev_err(ndev,
 369                         "unable to send receive buffer's gpadl to netvsp\n");
 370                 goto cleanup;
 371         }
 372
 373         wait_for_completion(&net_device->channel_init_wait);
 374
 375         /* Check the response */
 376         resp = &init_packet->msg.v1_msg.send_recv_buf_complete;
 377         if (resp->status != NVSP_STAT_SUCCESS) {
 378                 netdev_err(ndev,
 379                            "Unable to complete receive buffer initialization with NetVsp - status %d\n",
 380                            resp->status);
 381                 ret = -EINVAL;
 382                 goto cleanup;
 383         }
 384
 385         /* Parse the response */
 386         netdev_dbg(ndev, "Receive sections: %u sub_allocs: size %u count: %u\n",
 387                    resp->num_sections, resp->sections[0].sub_alloc_size,
 388                    resp->sections[0].num_sub_allocs);
 389
 390         /* There should only be one section for the entire receive buffer */
 391         if (resp->num_sections != 1 || resp->sections[0].offset != 0) {
 392                 ret = -EINVAL;
 393                 goto cleanup;
 394         }
 395
 396         net_device->recv_section_size = resp->sections[0].sub_alloc_size;
 397         net_device->recv_section_cnt = resp->sections[0].num_sub_allocs;
 398
 399         /* Setup receive completion ring */
 400         net_device->recv_completion_cnt
 401                 = round_up(net_device->recv_section_cnt + 1,
 402                            PAGE_SIZE / sizeof(u64));
 403         ret = netvsc_alloc_recv_comp_ring(net_device, 0);
 404         if (ret)
 405                 goto cleanup;
 406
 407         /* Now setup the send buffer. */
 408         buf_size = device_info->send_sections * device_info->send_section_size;
 409         buf_size = round_up(buf_size, PAGE_SIZE);
 410
 411         net_device->send_buf = vzalloc(buf_size);
 412         if (!net_device->send_buf) {
 413                 netdev_err(ndev, "unable to allocate send buffer of size %u\n",
 414                            buf_size);
 415                 ret = -ENOMEM;
 416                 goto cleanup;
 417         }
 418
 419         /* Establish the gpadl handle for this buffer on this
 420          * channel.  Note: This call uses the vmbus connection rather
 421          * than the channel to establish the gpadl handle.
 422          */
 423         ret = vmbus_establish_gpadl(device->channel, net_device->send_buf,
 424                                     buf_size,
 425                                     &net_device->send_buf_gpadl_handle);
 426         if (ret != 0) {
 427                 netdev_err(ndev,
 428                            "unable to establish send buffer's gpadl\n");
 429                 goto cleanup;
 430         }
 431
 432         /* Notify the NetVsp of the gpadl handle */
 433         init_packet = &net_device->channel_init_pkt;
 434         memset(init_packet, 0, sizeof(struct nvsp_message));
 435         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
 436         init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
 437                 net_device->send_buf_gpadl_handle;
 438         init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;
 439
 440         trace_nvsp_send(ndev, init_packet);
 441
 442         /* Send the gpadl notification request */
 443         ret = vmbus_sendpacket(device->channel, init_packet,
 444                                sizeof(struct nvsp_message),
 445                                (unsigned long)init_packet,
 446                                VM_PKT_DATA_INBAND,
 447                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 448         if (ret != 0) {
 449                 netdev_err(ndev,
 450                            "unable to send send buffer's gpadl to netvsp\n");
 451                 goto cleanup;
 452         }
 453
 454         wait_for_completion(&net_device->channel_init_wait);
 455
 456         /* Check the response */
 457         if (init_packet->msg.v1_msg.
 458             send_send_buf_complete.status != NVSP_STAT_SUCCESS) {
 459                 netdev_err(ndev, "Unable to complete send buffer "
 460                            "initialization with NetVsp - status %d\n",
 461                            init_packet->msg.v1_msg.
 462                            send_send_buf_complete.status);
 463                 ret = -EINVAL;
 464                 goto cleanup;
 465         }
 466
 467         /* Parse the response */
 468         net_device->send_section_size = init_packet->msg.
 469                                 v1_msg.send_send_buf_complete.section_size;
 470
 471         /* Section count is simply the size divided by the section size. */
 472         net_device->send_section_cnt = buf_size / net_device->send_section_size;
 473
 474         netdev_dbg(ndev, "Send section size: %d, Section count:%d\n",
 475                    net_device->send_section_size, net_device->send_section_cnt);
 476
 477         /* Setup state for managing the send buffer. */
 478         map_words = DIV_ROUND_UP(net_device->send_section_cnt, BITS_PER_LONG);
 479
 480         net_device->send_section_map = kcalloc(map_words, sizeof(ulong), GFP_KERNEL);
 481         if (net_device->send_section_map == NULL) {
 482                 ret = -ENOMEM;
 483                 goto cleanup;
 484         }
 485
 486         goto exit;
 487
 488 cleanup:
 489         netvsc_revoke_recv_buf(device, net_device, ndev);
 490         netvsc_revoke_send_buf(device, net_device, ndev);
 491         netvsc_teardown_recv_gpadl(device, net_device, ndev);
 492         netvsc_teardown_send_gpadl(device, net_device, ndev);
 493
 494 exit:
 495         return ret;
 496 }
 497
 498 /* Negotiate NVSP protocol version */
 499 static int negotiate_nvsp_ver(struct hv_device *device,
 500                               struct netvsc_device *net_device,
 501                               struct nvsp_message *init_packet,
 502                               u32 nvsp_ver)
 503 {
 504         struct net_device *ndev = hv_get_drvdata(device);
 505         int ret;
 506
 507         memset(init_packet, 0, sizeof(struct nvsp_message));
 508         init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
 509         init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
 510         init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
 511         trace_nvsp_send(ndev, init_packet);
 512
 513         /* Send the init request */
 514         ret = vmbus_sendpacket(device->channel, init_packet,
 515                                sizeof(struct nvsp_message),
 516                                (unsigned long)init_packet,
 517                                VM_PKT_DATA_INBAND,
 518                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 519
 520         if (ret != 0)
 521                 return ret;
 522
 523         wait_for_completion(&net_device->channel_init_wait);
 524
 525         if (init_packet->msg.init_msg.init_complete.status !=
 526             NVSP_STAT_SUCCESS)
 527                 return -EINVAL;
 528
 529         if (nvsp_ver == NVSP_PROTOCOL_VERSION_1)
 530                 return 0;
 531
 532         /* NVSPv2 or later: Send NDIS config */
 533         memset(init_packet, 0, sizeof(struct nvsp_message));
 534         init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
 535         init_packet->msg.v2_msg.send_ndis_config.mtu = ndev->mtu + ETH_HLEN;
 536         init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
 537
 538         if (nvsp_ver >= NVSP_PROTOCOL_VERSION_5) {
 539                 init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
 540
 541                 /* Teaming bit is needed to receive link speed updates */
 542                 init_packet->msg.v2_msg.send_ndis_config.capability.teaming = 1;
 543         }
 544
 545         if (nvsp_ver >= NVSP_PROTOCOL_VERSION_61)
 546                 init_packet->msg.v2_msg.send_ndis_config.capability.rsc = 1;
 547
 548         trace_nvsp_send(ndev, init_packet);
 549
 550         ret = vmbus_sendpacket(device->channel, init_packet,
 551                                 sizeof(struct nvsp_message),
 552                                 (unsigned long)init_packet,
 553                                 VM_PKT_DATA_INBAND, 0);
 554
 555         return ret;
 556 }
 557
 558 static int netvsc_connect_vsp(struct hv_device *device,
 559                               struct netvsc_device *net_device,
 560                               const struct netvsc_device_info *device_info)
 561 {
 562         struct net_device *ndev = hv_get_drvdata(device);
 563         static const u32 ver_list[] = {
 564                 NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
 565                 NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5,
 566                 NVSP_PROTOCOL_VERSION_6, NVSP_PROTOCOL_VERSION_61
 567         };
 568         struct nvsp_message *init_packet;
 569         int ndis_version, i, ret;
 570
 571         init_packet = &net_device->channel_init_pkt;
 572
 573         /* Negotiate the latest NVSP protocol supported */
 574         for (i = ARRAY_SIZE(ver_list) - 1; i >= 0; i--)
 575                 if (negotiate_nvsp_ver(device, net_device, init_packet,
 576                                        ver_list[i])  == 0) {
 577                         net_device->nvsp_version = ver_list[i];
 578                         break;
 579                 }
 580
 581         if (i < 0) {
 582                 ret = -EPROTO;
 583                 goto cleanup;
 584         }
 585
 586         pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
 587
 588         /* Send the ndis version */
 589         memset(init_packet, 0, sizeof(struct nvsp_message));
 590
 591         if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_4)
 592                 ndis_version = 0x00060001;
 593         else
 594                 ndis_version = 0x0006001e;
 595
 596         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
 597         init_packet->msg.v1_msg.
 598                 send_ndis_ver.ndis_major_ver =
 599                                 (ndis_version & 0xFFFF0000) >> 16;
 600         init_packet->msg.v1_msg.
 601                 send_ndis_ver.ndis_minor_ver =
 602                                 ndis_version & 0xFFFF;
 603
 604         trace_nvsp_send(ndev, init_packet);
 605
 606         /* Send the init request */
 607         ret = vmbus_sendpacket(device->channel, init_packet,
 608                                 sizeof(struct nvsp_message),
 609                                 (unsigned long)init_packet,
 610                                 VM_PKT_DATA_INBAND, 0);
 611         if (ret != 0)
 612                 goto cleanup;
 613
 614
 615         ret = netvsc_init_buf(device, net_device, device_info);
 616
 617 cleanup:
 618         return ret;
 619 }
 620
 621 /*
 622  * netvsc_device_remove - Callback when the root bus device is removed
 623  */
 624 void netvsc_device_remove(struct hv_device *device)
 625 {
 626         struct net_device *ndev = hv_get_drvdata(device);
 627         struct net_device_context *net_device_ctx = netdev_priv(ndev);
 628         struct netvsc_device *net_device
 629                 = rtnl_dereference(net_device_ctx->nvdev);
 630         int i;
 631
 632         /*
 633          * Revoke receive buffer. If host is pre-Win2016 then tear down
 634          * receive buffer GPADL. Do the same for send buffer.
 635          */
 636         netvsc_revoke_recv_buf(device, net_device, ndev);
 637         if (vmbus_proto_version < VERSION_WIN10)
 638                 netvsc_teardown_recv_gpadl(device, net_device, ndev);
 639
 640         netvsc_revoke_send_buf(device, net_device, ndev);
 641         if (vmbus_proto_version < VERSION_WIN10)
 642                 netvsc_teardown_send_gpadl(device, net_device, ndev);
 643
 644         RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
 645
 646         /* And disassociate NAPI context from device */
 647         for (i = 0; i < net_device->num_chn; i++)
 648                 netif_napi_del(&net_device->chan_table[i].napi);
 649
 650         /*
 651          * At this point, no one should be accessing net_device
 652          * except in here
 653          */
 654         netdev_dbg(ndev, "net device safe to remove\n");
 655
 656         /* Now, we can close the channel safely */
 657         vmbus_close(device->channel);
 658
 659         /*
 660          * If host is Win2016 or higher then we do the GPADL tear down
 661          * here after VMBus is closed.
 662         */
 663         if (vmbus_proto_version >= VERSION_WIN10) {
 664                 netvsc_teardown_recv_gpadl(device, net_device, ndev);
 665                 netvsc_teardown_send_gpadl(device, net_device, ndev);
 666         }
 667
 668         /* Release all resources */
 669         free_netvsc_device_rcu(net_device);
 670 }
 671
 672 #define RING_AVAIL_PERCENT_HIWATER 20
 673 #define RING_AVAIL_PERCENT_LOWATER 10
 674
 675 static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
 676                                          u32 index)
 677 {
 678         sync_change_bit(index, net_device->send_section_map);
 679 }
 680
 681 static void netvsc_send_tx_complete(struct net_device *ndev,
 682                                     struct netvsc_device *net_device,
 683                                     struct vmbus_channel *channel,
 684                                     const struct vmpacket_descriptor *desc,
 685                                     int budget)
 686 {
 687         struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->trans_id;
 688         struct net_device_context *ndev_ctx = netdev_priv(ndev);
 689         u16 q_idx = 0;
 690         int queue_sends;
 691
 692         /* Notify the layer above us */
 693         if (likely(skb)) {
 694                 const struct hv_netvsc_packet *packet
 695                         = (struct hv_netvsc_packet *)skb->cb;
 696                 u32 send_index = packet->send_buf_index;
 697                 struct netvsc_stats *tx_stats;
 698
 699                 if (send_index != NETVSC_INVALID_INDEX)
 700                         netvsc_free_send_slot(net_device, send_index);
 701                 q_idx = packet->q_idx;
 702
 703                 tx_stats = &net_device->chan_table[q_idx].tx_stats;
 704
 705                 u64_stats_update_begin(&tx_stats->syncp);
 706                 tx_stats->packets += packet->total_packets;
 707                 tx_stats->bytes += packet->total_bytes;
 708                 u64_stats_update_end(&tx_stats->syncp);
 709
 710                 napi_consume_skb(skb, budget);
 711         }
 712
 713         queue_sends =
 714                 atomic_dec_return(&net_device->chan_table[q_idx].queue_sends);
 715
 716         if (unlikely(net_device->destroy)) {
 717                 if (queue_sends == 0)
 718                         wake_up(&net_device->wait_drain);
 719         } else {
 720                 struct netdev_queue *txq = netdev_get_tx_queue(ndev, q_idx);
 721
 722                 if (netif_tx_queue_stopped(txq) &&
 723                     (hv_get_avail_to_write_percent(&channel->outbound) >
 724                      RING_AVAIL_PERCENT_HIWATER || queue_sends < 1)) {
 725                         netif_tx_wake_queue(txq);
 726                         ndev_ctx->eth_stats.wake_queue++;
 727                 }
 728         }
 729 }
 730
 731 static void netvsc_send_completion(struct net_device *ndev,
 732                                    struct netvsc_device *net_device,
 733                                    struct vmbus_channel *incoming_channel,
 734                                    const struct vmpacket_descriptor *desc,
 735                                    int budget)
 736 {
 737         const struct nvsp_message *nvsp_packet = hv_pkt_data(desc);
 738
 739         switch (nvsp_packet->hdr.msg_type) {
 740         case NVSP_MSG_TYPE_INIT_COMPLETE:
 741         case NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE:
 742         case NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE:
 743         case NVSP_MSG5_TYPE_SUBCHANNEL:
 744                 /* Copy the response back */
 745                 memcpy(&net_device->channel_init_pkt, nvsp_packet,
 746                        sizeof(struct nvsp_message));
 747                 complete(&net_device->channel_init_wait);
 748                 break;
 749
 750         case NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE:
 751                 netvsc_send_tx_complete(ndev, net_device, incoming_channel,
 752                                         desc, budget);
 753                 break;
 754
 755         default:
 756                 netdev_err(ndev,
 757                            "Unknown send completion type %d received!!\n",
 758                            nvsp_packet->hdr.msg_type);
 759         }
 760 }
 761
 762 static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
 763 {
 764         unsigned long *map_addr = net_device->send_section_map;
 765         unsigned int i;
 766
 767         for_each_clear_bit(i, map_addr, net_device->send_section_cnt) {
 768                 if (sync_test_and_set_bit(i, map_addr) == 0)
 769                         return i;
 770         }
 771
 772         return NETVSC_INVALID_INDEX;
 773 }
 774
 775 static void netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 776                                     unsigned int section_index,
 777                                     u32 pend_size,
 778                                     struct hv_netvsc_packet *packet,
 779                                     struct rndis_message *rndis_msg,
 780                                     struct hv_page_buffer *pb,
 781                                     bool xmit_more)
 782 {
 783         char *start = net_device->send_buf;
 784         char *dest = start + (section_index * net_device->send_section_size)
 785                      + pend_size;
 786         int i;
 787         u32 padding = 0;
 788         u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
 789                 packet->page_buf_cnt;
 790         u32 remain;
 791
 792         /* Add padding */
 793         remain = packet->total_data_buflen & (net_device->pkt_align - 1);
 794         if (xmit_more && remain) {
 795                 padding = net_device->pkt_align - remain;
 796                 rndis_msg->msg_len += padding;
 797                 packet->total_data_buflen += padding;
 798         }
 799
 800         for (i = 0; i < page_count; i++) {
 801                 char *src = phys_to_virt(pb[i].pfn << PAGE_SHIFT);
 802                 u32 offset = pb[i].offset;
 803                 u32 len = pb[i].len;
 804
 805                 memcpy(dest, (src + offset), len);
 806                 dest += len;
 807         }
 808
 809         if (padding)
 810                 memset(dest, 0, padding);
 811 }
 812
 813 static inline int netvsc_send_pkt(
 814         struct hv_device *device,
 815         struct hv_netvsc_packet *packet,
 816         struct netvsc_device *net_device,
 817         struct hv_page_buffer *pb,
 818         struct sk_buff *skb)
 819 {
 820         struct nvsp_message nvmsg;
 821         struct nvsp_1_message_send_rndis_packet *rpkt =
 822                 &nvmsg.msg.v1_msg.send_rndis_pkt;
 823         struct netvsc_channel * const nvchan =
 824                 &net_device->chan_table[packet->q_idx];
 825         struct vmbus_channel *out_channel = nvchan->channel;
 826         struct net_device *ndev = hv_get_drvdata(device);
 827         struct net_device_context *ndev_ctx = netdev_priv(ndev);
 828         struct netdev_queue *txq = netdev_get_tx_queue(ndev, packet->q_idx);
 829         u64 req_id;
 830         int ret;
 831         u32 ring_avail = hv_get_avail_to_write_percent(&out_channel->outbound);
 832
 833         nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 834         if (skb)
 835                 rpkt->channel_type = 0;         /* 0 is RMC_DATA */
 836         else
 837                 rpkt->channel_type = 1;         /* 1 is RMC_CONTROL */
 838
 839         rpkt->send_buf_section_index = packet->send_buf_index;
 840         if (packet->send_buf_index == NETVSC_INVALID_INDEX)
 841                 rpkt->send_buf_section_size = 0;
 842         else
 843                 rpkt->send_buf_section_size = packet->total_data_buflen;
 844
 845         req_id = (ulong)skb;
 846
 847         if (out_channel->rescind)
 848                 return -ENODEV;
 849
 850         trace_nvsp_send_pkt(ndev, out_channel, rpkt);
 851
 852         if (packet->page_buf_cnt) {
 853                 if (packet->cp_partial)
 854                         pb += packet->rmsg_pgcnt;
 855
 856                 ret = vmbus_sendpacket_pagebuffer(out_channel,
 857                                                   pb, packet->page_buf_cnt,
 858                                                   &nvmsg, sizeof(nvmsg),
 859                                                   req_id);
 860         } else {
 861                 ret = vmbus_sendpacket(out_channel,
 862                                        &nvmsg, sizeof(nvmsg),
 863                                        req_id, VM_PKT_DATA_INBAND,
 864                                        VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 865         }
 866
 867         if (ret == 0) {
 868                 atomic_inc_return(&nvchan->queue_sends);
 869
 870                 if (ring_avail < RING_AVAIL_PERCENT_LOWATER) {
 871                         netif_tx_stop_queue(txq);
 872                         ndev_ctx->eth_stats.stop_queue++;
 873                 }
 874         } else if (ret == -EAGAIN) {
 875                 netif_tx_stop_queue(txq);
 876                 ndev_ctx->eth_stats.stop_queue++;
 877                 if (atomic_read(&nvchan->queue_sends) < 1) {
 878                         netif_tx_wake_queue(txq);
 879                         ndev_ctx->eth_stats.wake_queue++;
 880                         ret = -ENOSPC;
 881                 }
 882         } else {
 883                 netdev_err(ndev,
 884                            "Unable to send packet pages %u len %u, ret %d\n",
 885                            packet->page_buf_cnt, packet->total_data_buflen,
 886                            ret);
 887         }
 888
 889         return ret;
 890 }
 891
 892 /* Move packet out of multi send data (msd), and clear msd */
 893 static inline void move_pkt_msd(struct hv_netvsc_packet **msd_send,
 894                                 struct sk_buff **msd_skb,
 895                                 struct multi_send_data *msdp)
 896 {
 897         *msd_skb = msdp->skb;
 898         *msd_send = msdp->pkt;
 899         msdp->skb = NULL;
 900         msdp->pkt = NULL;
 901         msdp->count = 0;
 902 }
 903
 904 /* RCU already held by caller */
 905 int netvsc_send(struct net_device *ndev,
 906                 struct hv_netvsc_packet *packet,
 907                 struct rndis_message *rndis_msg,
 908                 struct hv_page_buffer *pb,
 909                 struct sk_buff *skb)
 910 {
 911         struct net_device_context *ndev_ctx = netdev_priv(ndev);
 912         struct netvsc_device *net_device
 913                 = rcu_dereference_bh(ndev_ctx->nvdev);
 914         struct hv_device *device = ndev_ctx->device_ctx;
 915         int ret = 0;
 916         struct netvsc_channel *nvchan;
 917         u32 pktlen = packet->total_data_buflen, msd_len = 0;
 918         unsigned int section_index = NETVSC_INVALID_INDEX;
 919         struct multi_send_data *msdp;
 920         struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
 921         struct sk_buff *msd_skb = NULL;
 922         bool try_batch, xmit_more;
 923
 924         /* If device is rescinded, return error and packet will get dropped. */
 925         if (unlikely(!net_device || net_device->destroy))
 926                 return -ENODEV;
 927
 928         nvchan = &net_device->chan_table[packet->q_idx];
 929         packet->send_buf_index = NETVSC_INVALID_INDEX;
 930         packet->cp_partial = false;
 931
 932         /* Send control message directly without accessing msd (Multi-Send
 933          * Data) field which may be changed during data packet processing.
 934          */
 935         if (!skb)
 936                 return netvsc_send_pkt(device, packet, net_device, pb, skb);
 937
 938         /* batch packets in send buffer if possible */
 939         msdp = &nvchan->msd;
 940         if (msdp->pkt)
 941                 msd_len = msdp->pkt->total_data_buflen;
 942
 943         try_batch =  msd_len > 0 && msdp->count < net_device->max_pkt;
 944         if (try_batch && msd_len + pktlen + net_device->pkt_align <
 945             net_device->send_section_size) {
 946                 section_index = msdp->pkt->send_buf_index;
 947
 948         } else if (try_batch && msd_len + packet->rmsg_size <
 949                    net_device->send_section_size) {
 950                 section_index = msdp->pkt->send_buf_index;
 951                 packet->cp_partial = true;
 952
 953         } else if (pktlen + net_device->pkt_align <
 954                    net_device->send_section_size) {
 955                 section_index = netvsc_get_next_send_section(net_device);
 956                 if (unlikely(section_index == NETVSC_INVALID_INDEX)) {
 957                         ++ndev_ctx->eth_stats.tx_send_full;
 958                 } else {
 959                         move_pkt_msd(&msd_send, &msd_skb, msdp);
 960                         msd_len = 0;
 961                 }
 962         }
 963
 964         /* Keep aggregating only if stack says more data is coming
 965          * and not doing mixed modes send and not flow blocked
 966          */
 967         xmit_more = skb->xmit_more &&
 968                 !packet->cp_partial &&
 969                 !netif_xmit_stopped(netdev_get_tx_queue(ndev, packet->q_idx));
 970
 971         if (section_index != NETVSC_INVALID_INDEX) {
 972                 netvsc_copy_to_send_buf(net_device,
 973                                         section_index, msd_len,
 974                                         packet, rndis_msg, pb, xmit_more);
 975
 976                 packet->send_buf_index = section_index;
 977
 978                 if (packet->cp_partial) {
 979                         packet->page_buf_cnt -= packet->rmsg_pgcnt;
 980                         packet->total_data_buflen = msd_len + packet->rmsg_size;
 981                 } else {
 982                         packet->page_buf_cnt = 0;
 983                         packet->total_data_buflen += msd_len;
 984                 }
 985
 986                 if (msdp->pkt) {
 987                         packet->total_packets += msdp->pkt->total_packets;
 988                         packet->total_bytes += msdp->pkt->total_bytes;
 989                 }
 990
 991                 if (msdp->skb)
 992                         dev_consume_skb_any(msdp->skb);
 993
 994                 if (xmit_more) {
 995                         msdp->skb = skb;
 996                         msdp->pkt = packet;
 997                         msdp->count++;
 998                 } else {
 999                         cur_send = packet;
1000                         msdp->skb = NULL;
1001                         msdp->pkt = NULL;
1002                         msdp->count = 0;
1003                 }
1004         } else {
1005                 move_pkt_msd(&msd_send, &msd_skb, msdp);
1006                 cur_send = packet;
1007         }
1008
1009         if (msd_send) {
1010                 int m_ret = netvsc_send_pkt(device, msd_send, net_device,
1011                                             NULL, msd_skb);
1012
1013                 if (m_ret != 0) {
1014                         netvsc_free_send_slot(net_device,
1015                                               msd_send->send_buf_index);
1016                         dev_kfree_skb_any(msd_skb);
1017                 }
1018         }
1019
1020         if (cur_send)
1021                 ret = netvsc_send_pkt(device, cur_send, net_device, pb, skb);
1022
1023         if (ret != 0 && section_index != NETVSC_INVALID_INDEX)
1024                 netvsc_free_send_slot(net_device, section_index);
1025
1026         return ret;
1027 }
1028
1029 /* Send pending recv completions */
1030 static int send_recv_completions(struct net_device *ndev,
1031                                  struct netvsc_device *nvdev,
1032                                  struct netvsc_channel *nvchan)
1033 {
1034         struct multi_recv_comp *mrc = &nvchan->mrc;
1035         struct recv_comp_msg {
1036                 struct nvsp_message_header hdr;
1037                 u32 status;
1038         }  __packed;
1039         struct recv_comp_msg msg = {
1040                 .hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE,
1041         };
1042         int ret;
1043
1044         while (mrc->first != mrc->next) {
1045                 const struct recv_comp_data *rcd
1046                         = mrc->slots + mrc->first;
1047
1048                 msg.status = rcd->status;
1049                 ret = vmbus_sendpacket(nvchan->channel, &msg, sizeof(msg),
1050                                        rcd->tid, VM_PKT_COMP, 0);
1051                 if (unlikely(ret)) {
1052                         struct net_device_context *ndev_ctx = netdev_priv(ndev);
1053
1054                         ++ndev_ctx->eth_stats.rx_comp_busy;
1055                         return ret;
1056                 }
1057
1058                 if (++mrc->first == nvdev->recv_completion_cnt)
1059                         mrc->first = 0;
1060         }
1061
1062         /* receive completion ring has been emptied */
1063         if (unlikely(nvdev->destroy))
1064                 wake_up(&nvdev->wait_drain);
1065
1066         return 0;
1067 }
1068
1069 /* Count how many receive completions are outstanding */
1070 static void recv_comp_slot_avail(const struct netvsc_device *nvdev,
1071                                  const struct multi_recv_comp *mrc,
1072                                  u32 *filled, u32 *avail)
1073 {
1074         u32 count = nvdev->recv_completion_cnt;
1075
1076         if (mrc->next >= mrc->first)
1077                 *filled = mrc->next - mrc->first;
1078         else
1079                 *filled = (count - mrc->first) + mrc->next;
1080
1081         *avail = count - *filled - 1;
1082 }
1083
1084 /* Add receive complete to ring to send to host. */
1085 static void enq_receive_complete(struct net_device *ndev,
1086                                  struct netvsc_device *nvdev, u16 q_idx,
1087                                  u64 tid, u32 status)
1088 {
1089         struct netvsc_channel *nvchan = &nvdev->chan_table[q_idx];
1090         struct multi_recv_comp *mrc = &nvchan->mrc;
1091         struct recv_comp_data *rcd;
1092         u32 filled, avail;
1093
1094         recv_comp_slot_avail(nvdev, mrc, &filled, &avail);
1095
1096         if (unlikely(filled > NAPI_POLL_WEIGHT)) {
1097                 send_recv_completions(ndev, nvdev, nvchan);
1098                 recv_comp_slot_avail(nvdev, mrc, &filled, &avail);
1099         }
1100
1101         if (unlikely(!avail)) {
1102                 netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",
1103                            q_idx, tid);
1104                 return;
1105         }
1106
1107         rcd = mrc->slots + mrc->next;
1108         rcd->tid = tid;
1109         rcd->status = status;
1110
1111         if (++mrc->next == nvdev->recv_completion_cnt)
1112                 mrc->next = 0;
1113 }
1114
1115 static int netvsc_receive(struct net_device *ndev,
1116                           struct netvsc_device *net_device,
1117                           struct netvsc_channel *nvchan,
1118                           const struct vmpacket_descriptor *desc,
1119                           const struct nvsp_message *nvsp)
1120 {
1121         struct net_device_context *net_device_ctx = netdev_priv(ndev);
1122         struct vmbus_channel *channel = nvchan->channel;
1123         const struct vmtransfer_page_packet_header *vmxferpage_packet
1124                 = container_of(desc, const struct vmtransfer_page_packet_header, d);
1125         u16 q_idx = channel->offermsg.offer.sub_channel_index;
1126         char *recv_buf = net_device->recv_buf;
1127         u32 status = NVSP_STAT_SUCCESS;
1128         int i;
1129         int count = 0;
1130
1131         /* Make sure this is a valid nvsp packet */
1132         if (unlikely(nvsp->hdr.msg_type != NVSP_MSG1_TYPE_SEND_RNDIS_PKT)) {
1133                 netif_err(net_device_ctx, rx_err, ndev,
1134                           "Unknown nvsp packet type received %u\n",
1135                           nvsp->hdr.msg_type);
1136                 return 0;
1137         }
1138
1139         if (unlikely(vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID)) {
1140                 netif_err(net_device_ctx, rx_err, ndev,
1141                           "Invalid xfer page set id - expecting %x got %x\n",
1142                           NETVSC_RECEIVE_BUFFER_ID,
1143                           vmxferpage_packet->xfer_pageset_id);
1144                 return 0;
1145         }
1146
1147         count = vmxferpage_packet->range_cnt;
1148
1149         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1150         for (i = 0; i < count; i++) {
1151                 u32 offset = vmxferpage_packet->ranges[i].byte_offset;
1152                 u32 buflen = vmxferpage_packet->ranges[i].byte_count;
1153                 void *data;
1154                 int ret;
1155
1156                 if (unlikely(offset + buflen > net_device->recv_buf_size)) {
1157                         nvchan->rsc.cnt = 0;
1158                         status = NVSP_STAT_FAIL;
1159                         netif_err(net_device_ctx, rx_err, ndev,
1160                                   "Packet offset:%u + len:%u too big\n",
1161                                   offset, buflen);
1162
1163                         continue;
1164                 }
1165
1166                 data = recv_buf + offset;
1167
1168                 nvchan->rsc.is_last = (i == count - 1);
1169
1170                 trace_rndis_recv(ndev, q_idx, data);
1171
1172                 /* Pass it to the upper layer */
1173                 ret = rndis_filter_receive(ndev, net_device,
1174                                            nvchan, data, buflen);
1175
1176                 if (unlikely(ret != NVSP_STAT_SUCCESS))
1177                         status = NVSP_STAT_FAIL;
1178         }
1179
1180         enq_receive_complete(ndev, net_device, q_idx,
1181                              vmxferpage_packet->d.trans_id, status);
1182
1183         return count;
1184 }
1185
1186 static void netvsc_send_table(struct net_device *ndev,
1187                               const struct nvsp_message *nvmsg)
1188 {
1189         struct net_device_context *net_device_ctx = netdev_priv(ndev);
1190         u32 count, *tab;
1191         int i;
1192
1193         count = nvmsg->msg.v5_msg.send_table.count;
1194         if (count != VRSS_SEND_TAB_SIZE) {
1195                 netdev_err(ndev, "Received wrong send-table size:%u\n", count);
1196                 return;
1197         }
1198
1199         tab = (u32 *)((unsigned long)&nvmsg->msg.v5_msg.send_table +
1200                       nvmsg->msg.v5_msg.send_table.offset);
1201
1202         for (i = 0; i < count; i++)
1203                 net_device_ctx->tx_table[i] = tab[i];
1204 }
1205
1206 static void netvsc_send_vf(struct net_device *ndev,
1207                            const struct nvsp_message *nvmsg)
1208 {
1209         struct net_device_context *net_device_ctx = netdev_priv(ndev);
1210
1211         net_device_ctx->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated;
1212         net_device_ctx->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial;
1213         netdev_info(ndev, "VF slot %u %s\n",
1214                     net_device_ctx->vf_serial,
1215                     net_device_ctx->vf_alloc ? "added" : "removed");
1216 }
1217
1218 static  void netvsc_receive_inband(struct net_device *ndev,
1219                                    const struct nvsp_message *nvmsg)
1220 {
1221         switch (nvmsg->hdr.msg_type) {
1222         case NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE:
1223                 netvsc_send_table(ndev, nvmsg);
1224                 break;
1225
1226         case NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION:
1227                 netvsc_send_vf(ndev, nvmsg);
1228                 break;
1229         }
1230 }
1231
1232 static int netvsc_process_raw_pkt(struct hv_device *device,
1233                                   struct netvsc_channel *nvchan,
1234                                   struct netvsc_device *net_device,
1235                                   struct net_device *ndev,
1236                                   const struct vmpacket_descriptor *desc,
1237                                   int budget)
1238 {
1239         struct vmbus_channel *channel = nvchan->channel;
1240         const struct nvsp_message *nvmsg = hv_pkt_data(desc);
1241
1242         trace_nvsp_recv(ndev, channel, nvmsg);
1243
1244         switch (desc->type) {
1245         case VM_PKT_COMP:
1246                 netvsc_send_completion(ndev, net_device, channel,
1247                                        desc, budget);
1248                 break;
1249
1250         case VM_PKT_DATA_USING_XFER_PAGES:
1251                 return netvsc_receive(ndev, net_device, nvchan,
1252                                       desc, nvmsg);
1253                 break;
1254
1255         case VM_PKT_DATA_INBAND:
1256                 netvsc_receive_inband(ndev, nvmsg);
1257                 break;
1258
1259         default:
1260                 netdev_err(ndev, "unhandled packet type %d, tid %llx\n",
1261                            desc->type, desc->trans_id);
1262                 break;
1263         }
1264
1265         return 0;
1266 }
1267
1268 static struct hv_device *netvsc_channel_to_device(struct vmbus_channel *channel)
1269 {
1270         struct vmbus_channel *primary = channel->primary_channel;
1271
1272         return primary ? primary->device_obj : channel->device_obj;
1273 }
1274
1275 /* Network processing softirq
1276  * Process data in incoming ring buffer from host
1277  * Stops when ring is empty or budget is met or exceeded.
1278  */
1279 int netvsc_poll(struct napi_struct *napi, int budget)
1280 {
1281         struct netvsc_channel *nvchan
1282                 = container_of(napi, struct netvsc_channel, napi);
1283         struct netvsc_device *net_device = nvchan->net_device;
1284         struct vmbus_channel *channel = nvchan->channel;
1285         struct hv_device *device = netvsc_channel_to_device(channel);
1286         struct net_device *ndev = hv_get_drvdata(device);
1287         int work_done = 0;
1288         int ret;
1289
1290         /* If starting a new interval */
1291         if (!nvchan->desc)
1292                 nvchan->desc = hv_pkt_iter_first(channel);
1293
1294         while (nvchan->desc && work_done < budget) {
1295                 work_done += netvsc_process_raw_pkt(device, nvchan, net_device,
1296                                                     ndev, nvchan->desc, budget);
1297                 nvchan->desc = hv_pkt_iter_next(channel, nvchan->desc);
1298         }
1299
1300         /* Send any pending receive completions */
1301         ret = send_recv_completions(ndev, net_device, nvchan);
1302
1303         /* If it did not exhaust NAPI budget this time
1304          *  and not doing busy poll
1305          * then re-enable host interrupts
1306          *  and reschedule if ring is not empty
1307          *   or sending receive completion failed.
1308          */
1309         if (work_done < budget &&
1310             napi_complete_done(napi, work_done) &&
1311             (ret || hv_end_read(&channel->inbound)) &&
1312             napi_schedule_prep(napi)) {
1313                 hv_begin_read(&channel->inbound);
1314                 __napi_schedule(napi);
1315         }
1316
1317         /* Driver may overshoot since multiple packets per descriptor */
1318         return min(work_done, budget);
1319 }
1320
1321 /* Call back when data is available in host ring buffer.
1322  * Processing is deferred until network softirq (NAPI)
1323  */
1324 void netvsc_channel_cb(void *context)
1325 {
1326         struct netvsc_channel *nvchan = context;
1327         struct vmbus_channel *channel = nvchan->channel;
1328         struct hv_ring_buffer_info *rbi = &channel->inbound;
1329
1330         /* preload first vmpacket descriptor */
1331         prefetch(hv_get_ring_buffer(rbi) + rbi->priv_read_index);
1332
1333         if (napi_schedule_prep(&nvchan->napi)) {
1334                 /* disable interupts from host */
1335                 hv_begin_read(rbi);
1336
1337                 __napi_schedule_irqoff(&nvchan->napi);
1338         }
1339 }
1340
1341 /*
1342  * netvsc_device_add - Callback when the device belonging to this
1343  * driver is added
1344  */
1345 struct netvsc_device *netvsc_device_add(struct hv_device *device,
1346                                 const struct netvsc_device_info *device_info)
1347 {
1348         int i, ret = 0;
1349         struct netvsc_device *net_device;
1350         struct net_device *ndev = hv_get_drvdata(device);
1351         struct net_device_context *net_device_ctx = netdev_priv(ndev);
1352
1353         net_device = alloc_net_device();
1354         if (!net_device)
1355                 return ERR_PTR(-ENOMEM);
1356
1357         for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
1358                 net_device_ctx->tx_table[i] = 0;
1359
1360         /* Because the device uses NAPI, all the interrupt batching and
1361          * control is done via Net softirq, not the channel handling
1362          */
1363         set_channel_read_mode(device->channel, HV_CALL_ISR);
1364
1365         /* If we're reopening the device we may have multiple queues, fill the
1366          * chn_table with the default channel to use it before subchannels are
1367          * opened.
1368          * Initialize the channel state before we open;
1369          * we can be interrupted as soon as we open the channel.
1370          */
1371
1372         for (i = 0; i < VRSS_CHANNEL_MAX; i++) {
1373                 struct netvsc_channel *nvchan = &net_device->chan_table[i];
1374
1375                 nvchan->channel = device->channel;
1376                 nvchan->net_device = net_device;
1377                 u64_stats_init(&nvchan->tx_stats.syncp);
1378                 u64_stats_init(&nvchan->rx_stats.syncp);
1379         }
1380
1381         /* Enable NAPI handler before init callbacks */
1382         netif_napi_add(ndev, &net_device->chan_table[0].napi,
1383                        netvsc_poll, NAPI_POLL_WEIGHT);
1384
1385         /* Open the channel */
1386         ret = vmbus_open(device->channel, netvsc_ring_bytes,
1387                          netvsc_ring_bytes,  NULL, 0,
1388                          netvsc_channel_cb, net_device->chan_table);
1389
1390         if (ret != 0) {
1391                 netdev_err(ndev, "unable to open channel: %d\n", ret);
1392                 goto cleanup;
1393         }
1394
1395         /* Channel is opened */
1396         netdev_dbg(ndev, "hv_netvsc channel opened successfully\n");
1397
1398         napi_enable(&net_device->chan_table[0].napi);
1399
1400         /* Connect with the NetVsp */
1401         ret = netvsc_connect_vsp(device, net_device, device_info);
1402         if (ret != 0) {
1403                 netdev_err(ndev,
1404                         "unable to connect to NetVSP - %d\n", ret);
1405                 goto close;
1406         }
1407
1408         /* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
1409          * populated.
1410          */
1411         rcu_assign_pointer(net_device_ctx->nvdev, net_device);
1412
1413         return net_device;
1414
1415 close:
1416         RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
1417         napi_disable(&net_device->chan_table[0].napi);
1418
1419         /* Now, we can close the channel safely */
1420         vmbus_close(device->channel);
1421
1422 cleanup:
1423         netif_napi_del(&net_device->chan_table[0].napi);
1424         free_netvsc_device(&net_device->rcu);
1425
1426         return ERR_PTR(ret);
1427 }