kernel/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 <asm/sync_bitops.h>
  33
  34 #include "hyperv_net.h"
  35
  36
  37 static struct netvsc_device *alloc_net_device(struct hv_device *device)
  38 {
  39         struct netvsc_device *net_device;
  40         struct net_device *ndev = hv_get_drvdata(device);
  41         int i;
  42
  43         net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
  44         if (!net_device)
  45                 return NULL;
  46
  47         net_device->cb_buffer = kzalloc(NETVSC_PACKET_SIZE, GFP_KERNEL);
  48         if (!net_device->cb_buffer) {
  49                 kfree(net_device);
  50                 return NULL;
  51         }
  52
  53         init_waitqueue_head(&net_device->wait_drain);
  54         net_device->start_remove = false;
  55         net_device->destroy = false;
  56         net_device->dev = device;
  57         net_device->ndev = ndev;
  58         net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
  59         net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
  60
  61         for (i = 0; i < num_online_cpus(); i++)
  62                 spin_lock_init(&net_device->msd[i].lock);
  63
  64         hv_set_drvdata(device, net_device);
  65         return net_device;
  66 }
  67
  68 static void free_netvsc_device(struct netvsc_device *nvdev)
  69 {
  70         kfree(nvdev->cb_buffer);
  71         kfree(nvdev);
  72 }
  73
  74 static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
  75 {
  76         struct netvsc_device *net_device;
  77
  78         net_device = hv_get_drvdata(device);
  79         if (net_device && net_device->destroy)
  80                 net_device = NULL;
  81
  82         return net_device;
  83 }
  84
  85 static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
  86 {
  87         struct netvsc_device *net_device;
  88
  89         net_device = hv_get_drvdata(device);
  90
  91         if (!net_device)
  92                 goto get_in_err;
  93
  94         if (net_device->destroy &&
  95                 atomic_read(&net_device->num_outstanding_sends) == 0)
  96                 net_device = NULL;
  97
  98 get_in_err:
  99         return net_device;
 100 }
 101
 102
 103 static int netvsc_destroy_buf(struct netvsc_device *net_device)
 104 {
 105         struct nvsp_message *revoke_packet;
 106         int ret = 0;
 107         struct net_device *ndev = net_device->ndev;
 108
 109         /*
 110          * If we got a section count, it means we received a
 111          * SendReceiveBufferComplete msg (ie sent
 112          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 113          * to send a revoke msg here
 114          */
 115         if (net_device->recv_section_cnt) {
 116                 /* Send the revoke receive buffer */
 117                 revoke_packet = &net_device->revoke_packet;
 118                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 119
 120                 revoke_packet->hdr.msg_type =
 121                         NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
 122                 revoke_packet->msg.v1_msg.
 123                 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 124
 125                 ret = vmbus_sendpacket(net_device->dev->channel,
 126                                        revoke_packet,
 127                                        sizeof(struct nvsp_message),
 128                                        (unsigned long)revoke_packet,
 129                                        VM_PKT_DATA_INBAND, 0);
 130                 /*
 131                  * If we failed here, we might as well return and
 132                  * have a leak rather than continue and a bugchk
 133                  */
 134                 if (ret != 0) {
 135                         netdev_err(ndev, "unable to send "
 136                                 "revoke receive buffer to netvsp\n");
 137                         return ret;
 138                 }
 139         }
 140
 141         /* Teardown the gpadl on the vsp end */
 142         if (net_device->recv_buf_gpadl_handle) {
 143                 ret = vmbus_teardown_gpadl(net_device->dev->channel,
 144                            net_device->recv_buf_gpadl_handle);
 145
 146                 /* If we failed here, we might as well return and have a leak
 147                  * rather than continue and a bugchk
 148                  */
 149                 if (ret != 0) {
 150                         netdev_err(ndev,
 151                                    "unable to teardown receive buffer's gpadl\n");
 152                         return ret;
 153                 }
 154                 net_device->recv_buf_gpadl_handle = 0;
 155         }
 156
 157         if (net_device->recv_buf) {
 158                 /* Free up the receive buffer */
 159                 vfree(net_device->recv_buf);
 160                 net_device->recv_buf = NULL;
 161         }
 162
 163         if (net_device->recv_section) {
 164                 net_device->recv_section_cnt = 0;
 165                 kfree(net_device->recv_section);
 166                 net_device->recv_section = NULL;
 167         }
 168
 169         /* Deal with the send buffer we may have setup.
 170          * If we got a  send section size, it means we received a
 171          * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
 172          * NVSP_MSG1_TYPE_SEND_SEND_BUF msg) therefore, we need
 173          * to send a revoke msg here
 174          */
 175         if (net_device->send_section_size) {
 176                 /* Send the revoke receive buffer */
 177                 revoke_packet = &net_device->revoke_packet;
 178                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 179
 180                 revoke_packet->hdr.msg_type =
 181                         NVSP_MSG1_TYPE_REVOKE_SEND_BUF;
 182                 revoke_packet->msg.v1_msg.revoke_send_buf.id =
 183                         NETVSC_SEND_BUFFER_ID;
 184
 185                 ret = vmbus_sendpacket(net_device->dev->channel,
 186                                        revoke_packet,
 187                                        sizeof(struct nvsp_message),
 188                                        (unsigned long)revoke_packet,
 189                                        VM_PKT_DATA_INBAND, 0);
 190                 /* If we failed here, we might as well return and
 191                  * have a leak rather than continue and a bugchk
 192                  */
 193                 if (ret != 0) {
 194                         netdev_err(ndev, "unable to send "
 195                                    "revoke send buffer to netvsp\n");
 196                         return ret;
 197                 }
 198         }
 199         /* Teardown the gpadl on the vsp end */
 200         if (net_device->send_buf_gpadl_handle) {
 201                 ret = vmbus_teardown_gpadl(net_device->dev->channel,
 202                                            net_device->send_buf_gpadl_handle);
 203
 204                 /* If we failed here, we might as well return and have a leak
 205                  * rather than continue and a bugchk
 206                  */
 207                 if (ret != 0) {
 208                         netdev_err(ndev,
 209                                    "unable to teardown send buffer's gpadl\n");
 210                         return ret;
 211                 }
 212                 net_device->send_buf_gpadl_handle = 0;
 213         }
 214         if (net_device->send_buf) {
 215                 /* Free up the send buffer */
 216                 vfree(net_device->send_buf);
 217                 net_device->send_buf = NULL;
 218         }
 219         kfree(net_device->send_section_map);
 220
 221         return ret;
 222 }
 223
 224 static int netvsc_init_buf(struct hv_device *device)
 225 {
 226         int ret = 0;
 227         unsigned long t;
 228         struct netvsc_device *net_device;
 229         struct nvsp_message *init_packet;
 230         struct net_device *ndev;
 231         int node;
 232
 233         net_device = get_outbound_net_device(device);
 234         if (!net_device)
 235                 return -ENODEV;
 236         ndev = net_device->ndev;
 237
 238         node = cpu_to_node(device->channel->target_cpu);
 239         net_device->recv_buf = vzalloc_node(net_device->recv_buf_size, node);
 240         if (!net_device->recv_buf)
 241                 net_device->recv_buf = vzalloc(net_device->recv_buf_size);
 242
 243         if (!net_device->recv_buf) {
 244                 netdev_err(ndev, "unable to allocate receive "
 245                         "buffer of size %d\n", net_device->recv_buf_size);
 246                 ret = -ENOMEM;
 247                 goto cleanup;
 248         }
 249
 250         /*
 251          * Establish the gpadl handle for this buffer on this
 252          * channel.  Note: This call uses the vmbus connection rather
 253          * than the channel to establish the gpadl handle.
 254          */
 255         ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
 256                                     net_device->recv_buf_size,
 257                                     &net_device->recv_buf_gpadl_handle);
 258         if (ret != 0) {
 259                 netdev_err(ndev,
 260                         "unable to establish receive buffer's gpadl\n");
 261                 goto cleanup;
 262         }
 263
 264
 265         /* Notify the NetVsp of the gpadl handle */
 266         init_packet = &net_device->channel_init_pkt;
 267
 268         memset(init_packet, 0, sizeof(struct nvsp_message));
 269
 270         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 271         init_packet->msg.v1_msg.send_recv_buf.
 272                 gpadl_handle = net_device->recv_buf_gpadl_handle;
 273         init_packet->msg.v1_msg.
 274                 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 275
 276         /* Send the gpadl notification request */
 277         ret = vmbus_sendpacket(device->channel, init_packet,
 278                                sizeof(struct nvsp_message),
 279                                (unsigned long)init_packet,
 280                                VM_PKT_DATA_INBAND,
 281                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 282         if (ret != 0) {
 283                 netdev_err(ndev,
 284                         "unable to send receive buffer's gpadl to netvsp\n");
 285                 goto cleanup;
 286         }
 287
 288         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 289         BUG_ON(t == 0);
 290
 291
 292         /* Check the response */
 293         if (init_packet->msg.v1_msg.
 294             send_recv_buf_complete.status != NVSP_STAT_SUCCESS) {
 295                 netdev_err(ndev, "Unable to complete receive buffer "
 296                            "initialization with NetVsp - status %d\n",
 297                            init_packet->msg.v1_msg.
 298                            send_recv_buf_complete.status);
 299                 ret = -EINVAL;
 300                 goto cleanup;
 301         }
 302
 303         /* Parse the response */
 304
 305         net_device->recv_section_cnt = init_packet->msg.
 306                 v1_msg.send_recv_buf_complete.num_sections;
 307
 308         net_device->recv_section = kmemdup(
 309                 init_packet->msg.v1_msg.send_recv_buf_complete.sections,
 310                 net_device->recv_section_cnt *
 311                 sizeof(struct nvsp_1_receive_buffer_section),
 312                 GFP_KERNEL);
 313         if (net_device->recv_section == NULL) {
 314                 ret = -EINVAL;
 315                 goto cleanup;
 316         }
 317
 318         /*
 319          * For 1st release, there should only be 1 section that represents the
 320          * entire receive buffer
 321          */
 322         if (net_device->recv_section_cnt != 1 ||
 323             net_device->recv_section->offset != 0) {
 324                 ret = -EINVAL;
 325                 goto cleanup;
 326         }
 327
 328         /* Now setup the send buffer.
 329          */
 330         net_device->send_buf = vzalloc_node(net_device->send_buf_size, node);
 331         if (!net_device->send_buf)
 332                 net_device->send_buf = vzalloc(net_device->send_buf_size);
 333         if (!net_device->send_buf) {
 334                 netdev_err(ndev, "unable to allocate send "
 335                            "buffer of size %d\n", net_device->send_buf_size);
 336                 ret = -ENOMEM;
 337                 goto cleanup;
 338         }
 339
 340         /* Establish the gpadl handle for this buffer on this
 341          * channel.  Note: This call uses the vmbus connection rather
 342          * than the channel to establish the gpadl handle.
 343          */
 344         ret = vmbus_establish_gpadl(device->channel, net_device->send_buf,
 345                                     net_device->send_buf_size,
 346                                     &net_device->send_buf_gpadl_handle);
 347         if (ret != 0) {
 348                 netdev_err(ndev,
 349                            "unable to establish send buffer's gpadl\n");
 350                 goto cleanup;
 351         }
 352
 353         /* Notify the NetVsp of the gpadl handle */
 354         init_packet = &net_device->channel_init_pkt;
 355         memset(init_packet, 0, sizeof(struct nvsp_message));
 356         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
 357         init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
 358                 net_device->send_buf_gpadl_handle;
 359         init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;
 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 send buffer's gpadl to netvsp\n");
 370                 goto cleanup;
 371         }
 372
 373         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 374         BUG_ON(t == 0);
 375
 376         /* Check the response */
 377         if (init_packet->msg.v1_msg.
 378             send_send_buf_complete.status != NVSP_STAT_SUCCESS) {
 379                 netdev_err(ndev, "Unable to complete send buffer "
 380                            "initialization with NetVsp - status %d\n",
 381                            init_packet->msg.v1_msg.
 382                            send_send_buf_complete.status);
 383                 ret = -EINVAL;
 384                 goto cleanup;
 385         }
 386
 387         /* Parse the response */
 388         net_device->send_section_size = init_packet->msg.
 389                                 v1_msg.send_send_buf_complete.section_size;
 390
 391         /* Section count is simply the size divided by the section size.
 392          */
 393         net_device->send_section_cnt =
 394                 net_device->send_buf_size/net_device->send_section_size;
 395
 396         dev_info(&device->device, "Send section size: %d, Section count:%d\n",
 397                  net_device->send_section_size, net_device->send_section_cnt);
 398
 399         /* Setup state for managing the send buffer. */
 400         net_device->map_words = DIV_ROUND_UP(net_device->send_section_cnt,
 401                                              BITS_PER_LONG);
 402
 403         net_device->send_section_map =
 404                 kzalloc(net_device->map_words * sizeof(ulong), GFP_KERNEL);
 405         if (net_device->send_section_map == NULL) {
 406                 ret = -ENOMEM;
 407                 goto cleanup;
 408         }
 409
 410         goto exit;
 411
 412 cleanup:
 413         netvsc_destroy_buf(net_device);
 414
 415 exit:
 416         return ret;
 417 }
 418
 419
 420 /* Negotiate NVSP protocol version */
 421 static int negotiate_nvsp_ver(struct hv_device *device,
 422                               struct netvsc_device *net_device,
 423                               struct nvsp_message *init_packet,
 424                               u32 nvsp_ver)
 425 {
 426         int ret;
 427         unsigned long t;
 428
 429         memset(init_packet, 0, sizeof(struct nvsp_message));
 430         init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
 431         init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
 432         init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
 433
 434         /* Send the init request */
 435         ret = vmbus_sendpacket(device->channel, init_packet,
 436                                sizeof(struct nvsp_message),
 437                                (unsigned long)init_packet,
 438                                VM_PKT_DATA_INBAND,
 439                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 440
 441         if (ret != 0)
 442                 return ret;
 443
 444         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 445
 446         if (t == 0)
 447                 return -ETIMEDOUT;
 448
 449         if (init_packet->msg.init_msg.init_complete.status !=
 450             NVSP_STAT_SUCCESS)
 451                 return -EINVAL;
 452
 453         if (nvsp_ver == NVSP_PROTOCOL_VERSION_1)
 454                 return 0;
 455
 456         /* NVSPv2 or later: Send NDIS config */
 457         memset(init_packet, 0, sizeof(struct nvsp_message));
 458         init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
 459         init_packet->msg.v2_msg.send_ndis_config.mtu = net_device->ndev->mtu +
 460                                                        ETH_HLEN;
 461         init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
 462
 463         if (nvsp_ver >= NVSP_PROTOCOL_VERSION_5)
 464                 init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
 465
 466         ret = vmbus_sendpacket(device->channel, init_packet,
 467                                 sizeof(struct nvsp_message),
 468                                 (unsigned long)init_packet,
 469                                 VM_PKT_DATA_INBAND, 0);
 470
 471         return ret;
 472 }
 473
 474 static int netvsc_connect_vsp(struct hv_device *device)
 475 {
 476         int ret;
 477         struct netvsc_device *net_device;
 478         struct nvsp_message *init_packet;
 479         int ndis_version;
 480         struct net_device *ndev;
 481         u32 ver_list[] = { NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
 482                 NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5 };
 483         int i, num_ver = 4; /* number of different NVSP versions */
 484
 485         net_device = get_outbound_net_device(device);
 486         if (!net_device)
 487                 return -ENODEV;
 488         ndev = net_device->ndev;
 489
 490         init_packet = &net_device->channel_init_pkt;
 491
 492         /* Negotiate the latest NVSP protocol supported */
 493         for (i = num_ver - 1; i >= 0; i--)
 494                 if (negotiate_nvsp_ver(device, net_device, init_packet,
 495                                        ver_list[i])  == 0) {
 496                         net_device->nvsp_version = ver_list[i];
 497                         break;
 498                 }
 499
 500         if (i < 0) {
 501                 ret = -EPROTO;
 502                 goto cleanup;
 503         }
 504
 505         pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
 506
 507         /* Send the ndis version */
 508         memset(init_packet, 0, sizeof(struct nvsp_message));
 509
 510         if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_4)
 511                 ndis_version = 0x00060001;
 512         else
 513                 ndis_version = 0x0006001e;
 514
 515         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
 516         init_packet->msg.v1_msg.
 517                 send_ndis_ver.ndis_major_ver =
 518                                 (ndis_version & 0xFFFF0000) >> 16;
 519         init_packet->msg.v1_msg.
 520                 send_ndis_ver.ndis_minor_ver =
 521                                 ndis_version & 0xFFFF;
 522
 523         /* Send the init request */
 524         ret = vmbus_sendpacket(device->channel, init_packet,
 525                                 sizeof(struct nvsp_message),
 526                                 (unsigned long)init_packet,
 527                                 VM_PKT_DATA_INBAND, 0);
 528         if (ret != 0)
 529                 goto cleanup;
 530
 531         /* Post the big receive buffer to NetVSP */
 532         if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
 533                 net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
 534         else
 535                 net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
 536         net_device->send_buf_size = NETVSC_SEND_BUFFER_SIZE;
 537
 538         ret = netvsc_init_buf(device);
 539
 540 cleanup:
 541         return ret;
 542 }
 543
 544 static void netvsc_disconnect_vsp(struct netvsc_device *net_device)
 545 {
 546         netvsc_destroy_buf(net_device);
 547 }
 548
 549 /*
 550  * netvsc_device_remove - Callback when the root bus device is removed
 551  */
 552 int netvsc_device_remove(struct hv_device *device)
 553 {
 554         struct netvsc_device *net_device;
 555         unsigned long flags;
 556
 557         net_device = hv_get_drvdata(device);
 558
 559         netvsc_disconnect_vsp(net_device);
 560
 561         /*
 562          * Since we have already drained, we don't need to busy wait
 563          * as was done in final_release_stor_device()
 564          * Note that we cannot set the ext pointer to NULL until
 565          * we have drained - to drain the outgoing packets, we need to
 566          * allow incoming packets.
 567          */
 568
 569         spin_lock_irqsave(&device->channel->inbound_lock, flags);
 570         hv_set_drvdata(device, NULL);
 571         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
 572
 573         /*
 574          * At this point, no one should be accessing net_device
 575          * except in here
 576          */
 577         dev_notice(&device->device, "net device safe to remove\n");
 578
 579         /* Now, we can close the channel safely */
 580         vmbus_close(device->channel);
 581
 582         /* Release all resources */
 583         vfree(net_device->sub_cb_buf);
 584         free_netvsc_device(net_device);
 585         return 0;
 586 }
 587
 588
 589 #define RING_AVAIL_PERCENT_HIWATER 20
 590 #define RING_AVAIL_PERCENT_LOWATER 10
 591
 592 /*
 593  * Get the percentage of available bytes to write in the ring.
 594  * The return value is in range from 0 to 100.
 595  */
 596 static inline u32 hv_ringbuf_avail_percent(
 597                 struct hv_ring_buffer_info *ring_info)
 598 {
 599         u32 avail_read, avail_write;
 600
 601         hv_get_ringbuffer_availbytes(ring_info, &avail_read, &avail_write);
 602
 603         return avail_write * 100 / ring_info->ring_datasize;
 604 }
 605
 606 static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
 607                                          u32 index)
 608 {
 609         sync_change_bit(index, net_device->send_section_map);
 610 }
 611
 612 static void netvsc_send_completion(struct netvsc_device *net_device,
 613                                    struct hv_device *device,
 614                                    struct vmpacket_descriptor *packet)
 615 {
 616         struct nvsp_message *nvsp_packet;
 617         struct hv_netvsc_packet *nvsc_packet;
 618         struct net_device *ndev;
 619         u32 send_index;
 620
 621         ndev = net_device->ndev;
 622
 623         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 624                         (packet->offset8 << 3));
 625
 626         if ((nvsp_packet->hdr.msg_type == NVSP_MSG_TYPE_INIT_COMPLETE) ||
 627             (nvsp_packet->hdr.msg_type ==
 628              NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE) ||
 629             (nvsp_packet->hdr.msg_type ==
 630              NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE) ||
 631             (nvsp_packet->hdr.msg_type ==
 632              NVSP_MSG5_TYPE_SUBCHANNEL)) {
 633                 /* Copy the response back */
 634                 memcpy(&net_device->channel_init_pkt, nvsp_packet,
 635                        sizeof(struct nvsp_message));
 636                 complete(&net_device->channel_init_wait);
 637         } else if (nvsp_packet->hdr.msg_type ==
 638                    NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE) {
 639                 int num_outstanding_sends;
 640                 u16 q_idx = 0;
 641                 struct vmbus_channel *channel = device->channel;
 642                 int queue_sends;
 643
 644                 /* Get the send context */
 645                 nvsc_packet = (struct hv_netvsc_packet *)(unsigned long)
 646                         packet->trans_id;
 647
 648                 /* Notify the layer above us */
 649                 if (nvsc_packet) {
 650                         send_index = nvsc_packet->send_buf_index;
 651                         if (send_index != NETVSC_INVALID_INDEX)
 652                                 netvsc_free_send_slot(net_device, send_index);
 653                         q_idx = nvsc_packet->q_idx;
 654                         channel = nvsc_packet->channel;
 655                         nvsc_packet->send_completion(nvsc_packet->
 656                                                      send_completion_ctx);
 657                 }
 658
 659                 num_outstanding_sends =
 660                         atomic_dec_return(&net_device->num_outstanding_sends);
 661                 queue_sends = atomic_dec_return(&net_device->
 662                                                 queue_sends[q_idx]);
 663
 664                 if (net_device->destroy && num_outstanding_sends == 0)
 665                         wake_up(&net_device->wait_drain);
 666
 667                 if (netif_tx_queue_stopped(netdev_get_tx_queue(ndev, q_idx)) &&
 668                     !net_device->start_remove &&
 669                     (hv_ringbuf_avail_percent(&channel->outbound) >
 670                      RING_AVAIL_PERCENT_HIWATER || queue_sends < 1))
 671                                 netif_tx_wake_queue(netdev_get_tx_queue(
 672                                                     ndev, q_idx));
 673         } else {
 674                 netdev_err(ndev, "Unknown send completion packet type- "
 675                            "%d received!!\n", nvsp_packet->hdr.msg_type);
 676         }
 677
 678 }
 679
 680 static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
 681 {
 682         unsigned long index;
 683         u32 max_words = net_device->map_words;
 684         unsigned long *map_addr = (unsigned long *)net_device->send_section_map;
 685         u32 section_cnt = net_device->send_section_cnt;
 686         int ret_val = NETVSC_INVALID_INDEX;
 687         int i;
 688         int prev_val;
 689
 690         for (i = 0; i < max_words; i++) {
 691                 if (!~(map_addr[i]))
 692                         continue;
 693                 index = ffz(map_addr[i]);
 694                 prev_val = sync_test_and_set_bit(index, &map_addr[i]);
 695                 if (prev_val)
 696                         continue;
 697                 if ((index + (i * BITS_PER_LONG)) >= section_cnt)
 698                         break;
 699                 ret_val = (index + (i * BITS_PER_LONG));
 700                 break;
 701         }
 702         return ret_val;
 703 }
 704
 705 static u32 netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 706                                    unsigned int section_index,
 707                                    u32 pend_size,
 708                                    struct hv_netvsc_packet *packet)
 709 {
 710         char *start = net_device->send_buf;
 711         char *dest = start + (section_index * net_device->send_section_size)
 712                      + pend_size;
 713         int i;
 714         u32 msg_size = 0;
 715         u32 padding = 0;
 716         u32 remain = packet->total_data_buflen % net_device->pkt_align;
 717         u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
 718                 packet->page_buf_cnt;
 719
 720         /* Add padding */
 721         if (packet->is_data_pkt && packet->xmit_more && remain &&
 722             !packet->cp_partial) {
 723                 padding = net_device->pkt_align - remain;
 724                 packet->rndis_msg->msg_len += padding;
 725                 packet->total_data_buflen += padding;
 726         }
 727
 728         for (i = 0; i < page_count; i++) {
 729                 char *src = phys_to_virt(packet->page_buf[i].pfn << PAGE_SHIFT);
 730                 u32 offset = packet->page_buf[i].offset;
 731                 u32 len = packet->page_buf[i].len;
 732
 733                 memcpy(dest, (src + offset), len);
 734                 msg_size += len;
 735                 dest += len;
 736         }
 737
 738         if (padding) {
 739                 memset(dest, 0, padding);
 740                 msg_size += padding;
 741         }
 742
 743         return msg_size;
 744 }
 745
 746 static inline int netvsc_send_pkt(
 747         struct hv_netvsc_packet *packet,
 748         struct netvsc_device *net_device)
 749 {
 750         struct nvsp_message nvmsg;
 751         struct vmbus_channel *out_channel = packet->channel;
 752         u16 q_idx = packet->q_idx;
 753         struct net_device *ndev = net_device->ndev;
 754         u64 req_id;
 755         int ret;
 756         struct hv_page_buffer *pgbuf;
 757         u32 ring_avail = hv_ringbuf_avail_percent(&out_channel->outbound);
 758
 759         nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 760         if (packet->is_data_pkt) {
 761                 /* 0 is RMC_DATA; */
 762                 nvmsg.msg.v1_msg.send_rndis_pkt.channel_type = 0;
 763         } else {
 764                 /* 1 is RMC_CONTROL; */
 765                 nvmsg.msg.v1_msg.send_rndis_pkt.channel_type = 1;
 766         }
 767
 768         nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_index =
 769                 packet->send_buf_index;
 770         if (packet->send_buf_index == NETVSC_INVALID_INDEX)
 771                 nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_size = 0;
 772         else
 773                 nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_size =
 774                         packet->total_data_buflen;
 775
 776         if (packet->send_completion)
 777                 req_id = (ulong)packet;
 778         else
 779                 req_id = 0;
 780
 781         if (out_channel->rescind)
 782                 return -ENODEV;
 783
 784         /*
 785          * It is possible that once we successfully place this packet
 786          * on the ringbuffer, we may stop the queue. In that case, we want
 787          * to notify the host independent of the xmit_more flag. We don't
 788          * need to be precise here; in the worst case we may signal the host
 789          * unnecessarily.
 790          */
 791         if (ring_avail < (RING_AVAIL_PERCENT_LOWATER + 1))
 792                 packet->xmit_more = false;
 793
 794         if (packet->page_buf_cnt) {
 795                 pgbuf = packet->cp_partial ? packet->page_buf +
 796                         packet->rmsg_pgcnt : packet->page_buf;
 797                 ret = vmbus_sendpacket_pagebuffer_ctl(out_channel,
 798                                                       pgbuf,
 799                                                       packet->page_buf_cnt,
 800                                                       &nvmsg,
 801                                                       sizeof(struct nvsp_message),
 802                                                       req_id,
 803                                                       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED,
 804                                                       !packet->xmit_more);
 805         } else {
 806                 ret = vmbus_sendpacket_ctl(out_channel, &nvmsg,
 807                                            sizeof(struct nvsp_message),
 808                                            req_id,
 809                                            VM_PKT_DATA_INBAND,
 810                                            VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED,
 811                                            !packet->xmit_more);
 812         }
 813
 814         if (ret == 0) {
 815                 atomic_inc(&net_device->num_outstanding_sends);
 816                 atomic_inc(&net_device->queue_sends[q_idx]);
 817
 818                 if (ring_avail < RING_AVAIL_PERCENT_LOWATER) {
 819                         netif_tx_stop_queue(netdev_get_tx_queue(ndev, q_idx));
 820
 821                         if (atomic_read(&net_device->
 822                                 queue_sends[q_idx]) < 1)
 823                                 netif_tx_wake_queue(netdev_get_tx_queue(
 824                                                     ndev, q_idx));
 825                 }
 826         } else if (ret == -EAGAIN) {
 827                 netif_tx_stop_queue(netdev_get_tx_queue(
 828                                     ndev, q_idx));
 829                 if (atomic_read(&net_device->queue_sends[q_idx]) < 1) {
 830                         netif_tx_wake_queue(netdev_get_tx_queue(
 831                                             ndev, q_idx));
 832                         ret = -ENOSPC;
 833                 }
 834         } else {
 835                 netdev_err(ndev, "Unable to send packet %p ret %d\n",
 836                            packet, ret);
 837         }
 838
 839         return ret;
 840 }
 841
 842 int netvsc_send(struct hv_device *device,
 843                 struct hv_netvsc_packet *packet)
 844 {
 845         struct netvsc_device *net_device;
 846         int ret = 0, m_ret = 0;
 847         struct vmbus_channel *out_channel;
 848         u16 q_idx = packet->q_idx;
 849         u32 pktlen = packet->total_data_buflen, msd_len = 0;
 850         unsigned int section_index = NETVSC_INVALID_INDEX;
 851         unsigned long flag;
 852         struct multi_send_data *msdp;
 853         struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
 854         bool try_batch;
 855
 856         net_device = get_outbound_net_device(device);
 857         if (!net_device)
 858                 return -ENODEV;
 859
 860         out_channel = net_device->chn_table[q_idx];
 861         if (!out_channel) {
 862                 out_channel = device->channel;
 863                 q_idx = 0;
 864                 packet->q_idx = 0;
 865         }
 866         packet->channel = out_channel;
 867         packet->send_buf_index = NETVSC_INVALID_INDEX;
 868         packet->cp_partial = false;
 869
 870         msdp = &net_device->msd[q_idx];
 871
 872         /* batch packets in send buffer if possible */
 873         spin_lock_irqsave(&msdp->lock, flag);
 874         if (msdp->pkt)
 875                 msd_len = msdp->pkt->total_data_buflen;
 876
 877         try_batch = packet->is_data_pkt && msd_len > 0 && msdp->count <
 878                     net_device->max_pkt;
 879
 880         if (try_batch && msd_len + pktlen + net_device->pkt_align <
 881             net_device->send_section_size) {
 882                 section_index = msdp->pkt->send_buf_index;
 883
 884         } else if (try_batch && msd_len + packet->rmsg_size <
 885                    net_device->send_section_size) {
 886                 section_index = msdp->pkt->send_buf_index;
 887                 packet->cp_partial = true;
 888
 889         } else if (packet->is_data_pkt && pktlen + net_device->pkt_align <
 890                    net_device->send_section_size) {
 891                 section_index = netvsc_get_next_send_section(net_device);
 892                 if (section_index != NETVSC_INVALID_INDEX) {
 893                                 msd_send = msdp->pkt;
 894                                 msdp->pkt = NULL;
 895                                 msdp->count = 0;
 896                                 msd_len = 0;
 897                 }
 898         }
 899
 900         if (section_index != NETVSC_INVALID_INDEX) {
 901                 netvsc_copy_to_send_buf(net_device,
 902                                         section_index, msd_len,
 903                                         packet);
 904
 905                 packet->send_buf_index = section_index;
 906
 907                 if (packet->cp_partial) {
 908                         packet->page_buf_cnt -= packet->rmsg_pgcnt;
 909                         packet->total_data_buflen = msd_len + packet->rmsg_size;
 910                 } else {
 911                         packet->page_buf_cnt = 0;
 912                         packet->total_data_buflen += msd_len;
 913                 }
 914
 915                 if (msdp->pkt)
 916                         netvsc_xmit_completion(msdp->pkt);
 917
 918                 if (packet->xmit_more && !packet->cp_partial) {
 919                         msdp->pkt = packet;
 920                         msdp->count++;
 921                 } else {
 922                         cur_send = packet;
 923                         msdp->pkt = NULL;
 924                         msdp->count = 0;
 925                 }
 926         } else {
 927                 msd_send = msdp->pkt;
 928                 msdp->pkt = NULL;
 929                 msdp->count = 0;
 930                 cur_send = packet;
 931         }
 932
 933         spin_unlock_irqrestore(&msdp->lock, flag);
 934
 935         if (msd_send) {
 936                 m_ret = netvsc_send_pkt(msd_send, net_device);
 937
 938                 if (m_ret != 0) {
 939                         netvsc_free_send_slot(net_device,
 940                                               msd_send->send_buf_index);
 941                         netvsc_xmit_completion(msd_send);
 942                 }
 943         }
 944
 945         if (cur_send)
 946                 ret = netvsc_send_pkt(cur_send, net_device);
 947
 948         if (ret != 0 && section_index != NETVSC_INVALID_INDEX)
 949                 netvsc_free_send_slot(net_device, section_index);
 950
 951         return ret;
 952 }
 953
 954 static void netvsc_send_recv_completion(struct hv_device *device,
 955                                         struct vmbus_channel *channel,
 956                                         struct netvsc_device *net_device,
 957                                         u64 transaction_id, u32 status)
 958 {
 959         struct nvsp_message recvcompMessage;
 960         int retries = 0;
 961         int ret;
 962         struct net_device *ndev;
 963
 964         ndev = net_device->ndev;
 965
 966         recvcompMessage.hdr.msg_type =
 967                                 NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE;
 968
 969         recvcompMessage.msg.v1_msg.send_rndis_pkt_complete.status = status;
 970
 971 retry_send_cmplt:
 972         /* Send the completion */
 973         ret = vmbus_sendpacket(channel, &recvcompMessage,
 974                                sizeof(struct nvsp_message), transaction_id,
 975                                VM_PKT_COMP, 0);
 976         if (ret == 0) {
 977                 /* success */
 978                 /* no-op */
 979         } else if (ret == -EAGAIN) {
 980                 /* no more room...wait a bit and attempt to retry 3 times */
 981                 retries++;
 982                 netdev_err(ndev, "unable to send receive completion pkt"
 983                         " (tid %llx)...retrying %d\n", transaction_id, retries);
 984
 985                 if (retries < 4) {
 986                         udelay(100);
 987                         goto retry_send_cmplt;
 988                 } else {
 989                         netdev_err(ndev, "unable to send receive "
 990                                 "completion pkt (tid %llx)...give up retrying\n",
 991                                 transaction_id);
 992                 }
 993         } else {
 994                 netdev_err(ndev, "unable to send receive "
 995                         "completion pkt - %llx\n", transaction_id);
 996         }
 997 }
 998
 999 static void netvsc_receive(struct netvsc_device *net_device,
1000                         struct vmbus_channel *channel,
1001                         struct hv_device *device,
1002                         struct vmpacket_descriptor *packet)
1003 {
1004         struct vmtransfer_page_packet_header *vmxferpage_packet;
1005         struct nvsp_message *nvsp_packet;
1006         struct hv_netvsc_packet nv_pkt;
1007         struct hv_netvsc_packet *netvsc_packet = &nv_pkt;
1008         u32 status = NVSP_STAT_SUCCESS;
1009         int i;
1010         int count = 0;
1011         struct net_device *ndev;
1012
1013         ndev = net_device->ndev;
1014
1015         /*
1016          * All inbound packets other than send completion should be xfer page
1017          * packet
1018          */
1019         if (packet->type != VM_PKT_DATA_USING_XFER_PAGES) {
1020                 netdev_err(ndev, "Unknown packet type received - %d\n",
1021                            packet->type);
1022                 return;
1023         }
1024
1025         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
1026                         (packet->offset8 << 3));
1027
1028         /* Make sure this is a valid nvsp packet */
1029         if (nvsp_packet->hdr.msg_type !=
1030             NVSP_MSG1_TYPE_SEND_RNDIS_PKT) {
1031                 netdev_err(ndev, "Unknown nvsp packet type received-"
1032                         " %d\n", nvsp_packet->hdr.msg_type);
1033                 return;
1034         }
1035
1036         vmxferpage_packet = (struct vmtransfer_page_packet_header *)packet;
1037
1038         if (vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID) {
1039                 netdev_err(ndev, "Invalid xfer page set id - "
1040                            "expecting %x got %x\n", NETVSC_RECEIVE_BUFFER_ID,
1041                            vmxferpage_packet->xfer_pageset_id);
1042                 return;
1043         }
1044
1045         count = vmxferpage_packet->range_cnt;
1046         netvsc_packet->channel = channel;
1047
1048         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1049         for (i = 0; i < count; i++) {
1050                 /* Initialize the netvsc packet */
1051                 netvsc_packet->status = NVSP_STAT_SUCCESS;
1052                 netvsc_packet->data = (void *)((unsigned long)net_device->
1053                         recv_buf + vmxferpage_packet->ranges[i].byte_offset);
1054                 netvsc_packet->total_data_buflen =
1055                                         vmxferpage_packet->ranges[i].byte_count;
1056
1057                 /* Pass it to the upper layer */
1058                 rndis_filter_receive(device, netvsc_packet);
1059
1060                 if (netvsc_packet->status != NVSP_STAT_SUCCESS)
1061                         status = NVSP_STAT_FAIL;
1062         }
1063
1064         netvsc_send_recv_completion(device, channel, net_device,
1065                                     vmxferpage_packet->d.trans_id, status);
1066 }
1067
1068
1069 static void netvsc_send_table(struct hv_device *hdev,
1070                               struct nvsp_message *nvmsg)
1071 {
1072         struct netvsc_device *nvscdev;
1073         struct net_device *ndev;
1074         int i;
1075         u32 count, *tab;
1076
1077         nvscdev = get_outbound_net_device(hdev);
1078         if (!nvscdev)
1079                 return;
1080         ndev = nvscdev->ndev;
1081
1082         count = nvmsg->msg.v5_msg.send_table.count;
1083         if (count != VRSS_SEND_TAB_SIZE) {
1084                 netdev_err(ndev, "Received wrong send-table size:%u\n", count);
1085                 return;
1086         }
1087
1088         tab = (u32 *)((unsigned long)&nvmsg->msg.v5_msg.send_table +
1089                       nvmsg->msg.v5_msg.send_table.offset);
1090
1091         for (i = 0; i < count; i++)
1092                 nvscdev->send_table[i] = tab[i];
1093 }
1094
1095 static void netvsc_send_vf(struct netvsc_device *nvdev,
1096                            struct nvsp_message *nvmsg)
1097 {
1098         nvdev->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated;
1099         nvdev->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial;
1100 }
1101
1102 static inline void netvsc_receive_inband(struct hv_device *hdev,
1103                                          struct netvsc_device *nvdev,
1104                                          struct nvsp_message *nvmsg)
1105 {
1106         switch (nvmsg->hdr.msg_type) {
1107         case NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE:
1108                 netvsc_send_table(hdev, nvmsg);
1109                 break;
1110
1111         case NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION:
1112                 netvsc_send_vf(nvdev, nvmsg);
1113                 break;
1114         }
1115 }
1116
1117 void netvsc_channel_cb(void *context)
1118 {
1119         int ret;
1120         struct vmbus_channel *channel = (struct vmbus_channel *)context;
1121         struct hv_device *device;
1122         struct netvsc_device *net_device;
1123         u32 bytes_recvd;
1124         u64 request_id;
1125         struct vmpacket_descriptor *desc;
1126         unsigned char *buffer;
1127         int bufferlen = NETVSC_PACKET_SIZE;
1128         struct net_device *ndev;
1129         struct nvsp_message *nvmsg;
1130
1131         if (channel->primary_channel != NULL)
1132                 device = channel->primary_channel->device_obj;
1133         else
1134                 device = channel->device_obj;
1135
1136         net_device = get_inbound_net_device(device);
1137         if (!net_device)
1138                 return;
1139         ndev = net_device->ndev;
1140         buffer = get_per_channel_state(channel);
1141
1142         do {
1143                 ret = vmbus_recvpacket_raw(channel, buffer, bufferlen,
1144                                            &bytes_recvd, &request_id);
1145                 if (ret == 0) {
1146                         if (bytes_recvd > 0) {
1147                                 desc = (struct vmpacket_descriptor *)buffer;
1148                                 nvmsg = (struct nvsp_message *)((unsigned long)
1149                                          desc + (desc->offset8 << 3));
1150                                 switch (desc->type) {
1151                                 case VM_PKT_COMP:
1152                                         netvsc_send_completion(net_device,
1153                                                                 device, desc);
1154                                         break;
1155
1156                                 case VM_PKT_DATA_USING_XFER_PAGES:
1157                                         netvsc_receive(net_device, channel,
1158                                                        device, desc);
1159                                         break;
1160
1161                                 case VM_PKT_DATA_INBAND:
1162                                         netvsc_receive_inband(device,
1163                                                               net_device,
1164                                                               nvmsg);
1165                                         break;
1166
1167                                 default:
1168                                         netdev_err(ndev,
1169                                                    "unhandled packet type %d, "
1170                                                    "tid %llx len %d\n",
1171                                                    desc->type, request_id,
1172                                                    bytes_recvd);
1173                                         break;
1174                                 }
1175
1176                         } else {
1177                                 /*
1178                                  * We are done for this pass.
1179                                  */
1180                                 break;
1181                         }
1182
1183                 } else if (ret == -ENOBUFS) {
1184                         if (bufferlen > NETVSC_PACKET_SIZE)
1185                                 kfree(buffer);
1186                         /* Handle large packet */
1187                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
1188                         if (buffer == NULL) {
1189                                 /* Try again next time around */
1190                                 netdev_err(ndev,
1191                                            "unable to allocate buffer of size "
1192                                            "(%d)!!\n", bytes_recvd);
1193                                 break;
1194                         }
1195
1196                         bufferlen = bytes_recvd;
1197                 }
1198         } while (1);
1199
1200         if (bufferlen > NETVSC_PACKET_SIZE)
1201                 kfree(buffer);
1202         return;
1203 }
1204
1205 /*
1206  * netvsc_device_add - Callback when the device belonging to this
1207  * driver is added
1208  */
1209 int netvsc_device_add(struct hv_device *device, void *additional_info)
1210 {
1211         int ret = 0;
1212         int ring_size =
1213         ((struct netvsc_device_info *)additional_info)->ring_size;
1214         struct netvsc_device *net_device;
1215         struct net_device *ndev;
1216
1217         net_device = alloc_net_device(device);
1218         if (!net_device)
1219                 return -ENOMEM;
1220
1221         net_device->ring_size = ring_size;
1222
1223         /*
1224          * Coming into this function, struct net_device * is
1225          * registered as the driver private data.
1226          * In alloc_net_device(), we register struct netvsc_device *
1227          * as the driver private data and stash away struct net_device *
1228          * in struct netvsc_device *.
1229          */
1230         ndev = net_device->ndev;
1231
1232         /* Add netvsc_device context to netvsc_device */
1233         net_device->nd_ctx = netdev_priv(ndev);
1234
1235         /* Initialize the NetVSC channel extension */
1236         init_completion(&net_device->channel_init_wait);
1237
1238         set_per_channel_state(device->channel, net_device->cb_buffer);
1239
1240         /* Open the channel */
1241         ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
1242                          ring_size * PAGE_SIZE, NULL, 0,
1243                          netvsc_channel_cb, device->channel);
1244
1245         if (ret != 0) {
1246                 netdev_err(ndev, "unable to open channel: %d\n", ret);
1247                 goto cleanup;
1248         }
1249
1250         /* Channel is opened */
1251         pr_info("hv_netvsc channel opened successfully\n");
1252
1253         net_device->chn_table[0] = device->channel;
1254
1255         /* Connect with the NetVsp */
1256         ret = netvsc_connect_vsp(device);
1257         if (ret != 0) {
1258                 netdev_err(ndev,
1259                         "unable to connect to NetVSP - %d\n", ret);
1260                 goto close;
1261         }
1262
1263         return ret;
1264
1265 close:
1266         /* Now, we can close the channel safely */
1267         vmbus_close(device->channel);
1268
1269 cleanup:
1270         free_netvsc_device(net_device);
1271
1272         return ret;
1273 }