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  * Switch the data path from the synthetic interface to the VF
  38  * interface.
  39  */
  40 void netvsc_switch_datapath(struct net_device *ndev, bool vf)
  41 {
  42         struct net_device_context *net_device_ctx = netdev_priv(ndev);
  43         struct hv_device *dev = net_device_ctx->device_ctx;
  44         struct netvsc_device *nv_dev = net_device_ctx->nvdev;
  45         struct nvsp_message *init_pkt = &nv_dev->channel_init_pkt;
  46
  47         memset(init_pkt, 0, sizeof(struct nvsp_message));
  48         init_pkt->hdr.msg_type = NVSP_MSG4_TYPE_SWITCH_DATA_PATH;
  49         if (vf)
  50                 init_pkt->msg.v4_msg.active_dp.active_datapath =
  51                         NVSP_DATAPATH_VF;
  52         else
  53                 init_pkt->msg.v4_msg.active_dp.active_datapath =
  54                         NVSP_DATAPATH_SYNTHETIC;
  55
  56         vmbus_sendpacket(dev->channel, init_pkt,
  57                                sizeof(struct nvsp_message),
  58                                (unsigned long)init_pkt,
  59                                VM_PKT_DATA_INBAND, 0);
  60 }
  61
  62 static struct netvsc_device *alloc_net_device(void)
  63 {
  64         struct netvsc_device *net_device;
  65
  66         net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
  67         if (!net_device)
  68                 return NULL;
  69
  70         net_device->cb_buffer = kzalloc(NETVSC_PACKET_SIZE, GFP_KERNEL);
  71         if (!net_device->cb_buffer) {
  72                 kfree(net_device);
  73                 return NULL;
  74         }
  75
  76         net_device->mrc[0].buf = vzalloc(NETVSC_RECVSLOT_MAX *
  77                                          sizeof(struct recv_comp_data));
  78
  79         init_waitqueue_head(&net_device->wait_drain);
  80         net_device->destroy = false;
  81         atomic_set(&net_device->open_cnt, 0);
  82         net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
  83         net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
  84         init_completion(&net_device->channel_init_wait);
  85
  86         return net_device;
  87 }
  88
  89 static void free_netvsc_device(struct netvsc_device *nvdev)
  90 {
  91         int i;
  92
  93         for (i = 0; i < VRSS_CHANNEL_MAX; i++)
  94                 vfree(nvdev->mrc[i].buf);
  95
  96         kfree(nvdev->cb_buffer);
  97         kfree(nvdev);
  98 }
  99
 100 static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
 101 {
 102         struct netvsc_device *net_device = hv_device_to_netvsc_device(device);
 103
 104         if (net_device && net_device->destroy)
 105                 net_device = NULL;
 106
 107         return net_device;
 108 }
 109
 110 static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
 111 {
 112         struct netvsc_device *net_device = hv_device_to_netvsc_device(device);
 113
 114         if (!net_device)
 115                 goto get_in_err;
 116
 117         if (net_device->destroy &&
 118             atomic_read(&net_device->num_outstanding_sends) == 0 &&
 119             atomic_read(&net_device->num_outstanding_recvs) == 0)
 120                 net_device = NULL;
 121
 122 get_in_err:
 123         return net_device;
 124 }
 125
 126 static void netvsc_destroy_buf(struct hv_device *device)
 127 {
 128         struct nvsp_message *revoke_packet;
 129         struct net_device *ndev = hv_get_drvdata(device);
 130         struct netvsc_device *net_device = net_device_to_netvsc_device(ndev);
 131         int ret;
 132
 133         /*
 134          * If we got a section count, it means we received a
 135          * SendReceiveBufferComplete msg (ie sent
 136          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 137          * to send a revoke msg here
 138          */
 139         if (net_device->recv_section_cnt) {
 140                 /* Send the revoke receive buffer */
 141                 revoke_packet = &net_device->revoke_packet;
 142                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 143
 144                 revoke_packet->hdr.msg_type =
 145                         NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
 146                 revoke_packet->msg.v1_msg.
 147                 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 148
 149                 ret = vmbus_sendpacket(device->channel,
 150                                        revoke_packet,
 151                                        sizeof(struct nvsp_message),
 152                                        (unsigned long)revoke_packet,
 153                                        VM_PKT_DATA_INBAND, 0);
 154                 /*
 155                  * If we failed here, we might as well return and
 156                  * have a leak rather than continue and a bugchk
 157                  */
 158                 if (ret != 0) {
 159                         netdev_err(ndev, "unable to send "
 160                                 "revoke receive buffer to netvsp\n");
 161                         return;
 162                 }
 163         }
 164
 165         /* Teardown the gpadl on the vsp end */
 166         if (net_device->recv_buf_gpadl_handle) {
 167                 ret = vmbus_teardown_gpadl(device->channel,
 168                                            net_device->recv_buf_gpadl_handle);
 169
 170                 /* If we failed here, we might as well return and have a leak
 171                  * rather than continue and a bugchk
 172                  */
 173                 if (ret != 0) {
 174                         netdev_err(ndev,
 175                                    "unable to teardown receive buffer's gpadl\n");
 176                         return;
 177                 }
 178                 net_device->recv_buf_gpadl_handle = 0;
 179         }
 180
 181         if (net_device->recv_buf) {
 182                 /* Free up the receive buffer */
 183                 vfree(net_device->recv_buf);
 184                 net_device->recv_buf = NULL;
 185         }
 186
 187         if (net_device->recv_section) {
 188                 net_device->recv_section_cnt = 0;
 189                 kfree(net_device->recv_section);
 190                 net_device->recv_section = NULL;
 191         }
 192
 193         /* Deal with the send buffer we may have setup.
 194          * If we got a  send section size, it means we received a
 195          * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
 196          * NVSP_MSG1_TYPE_SEND_SEND_BUF msg) therefore, we need
 197          * to send a revoke msg here
 198          */
 199         if (net_device->send_section_size) {
 200                 /* Send the revoke receive buffer */
 201                 revoke_packet = &net_device->revoke_packet;
 202                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 203
 204                 revoke_packet->hdr.msg_type =
 205                         NVSP_MSG1_TYPE_REVOKE_SEND_BUF;
 206                 revoke_packet->msg.v1_msg.revoke_send_buf.id =
 207                         NETVSC_SEND_BUFFER_ID;
 208
 209                 ret = vmbus_sendpacket(device->channel,
 210                                        revoke_packet,
 211                                        sizeof(struct nvsp_message),
 212                                        (unsigned long)revoke_packet,
 213                                        VM_PKT_DATA_INBAND, 0);
 214                 /* If we failed here, we might as well return and
 215                  * have a leak rather than continue and a bugchk
 216                  */
 217                 if (ret != 0) {
 218                         netdev_err(ndev, "unable to send "
 219                                    "revoke send buffer to netvsp\n");
 220                         return;
 221                 }
 222         }
 223         /* Teardown the gpadl on the vsp end */
 224         if (net_device->send_buf_gpadl_handle) {
 225                 ret = vmbus_teardown_gpadl(device->channel,
 226                                            net_device->send_buf_gpadl_handle);
 227
 228                 /* If we failed here, we might as well return and have a leak
 229                  * rather than continue and a bugchk
 230                  */
 231                 if (ret != 0) {
 232                         netdev_err(ndev,
 233                                    "unable to teardown send buffer's gpadl\n");
 234                         return;
 235                 }
 236                 net_device->send_buf_gpadl_handle = 0;
 237         }
 238         if (net_device->send_buf) {
 239                 /* Free up the send buffer */
 240                 vfree(net_device->send_buf);
 241                 net_device->send_buf = NULL;
 242         }
 243         kfree(net_device->send_section_map);
 244 }
 245
 246 static int netvsc_init_buf(struct hv_device *device)
 247 {
 248         int ret = 0;
 249         struct netvsc_device *net_device;
 250         struct nvsp_message *init_packet;
 251         struct net_device *ndev;
 252         int node;
 253
 254         net_device = get_outbound_net_device(device);
 255         if (!net_device)
 256                 return -ENODEV;
 257         ndev = hv_get_drvdata(device);
 258
 259         node = cpu_to_node(device->channel->target_cpu);
 260         net_device->recv_buf = vzalloc_node(net_device->recv_buf_size, node);
 261         if (!net_device->recv_buf)
 262                 net_device->recv_buf = vzalloc(net_device->recv_buf_size);
 263
 264         if (!net_device->recv_buf) {
 265                 netdev_err(ndev, "unable to allocate receive "
 266                         "buffer of size %d\n", net_device->recv_buf_size);
 267                 ret = -ENOMEM;
 268                 goto cleanup;
 269         }
 270
 271         /*
 272          * Establish the gpadl handle for this buffer on this
 273          * channel.  Note: This call uses the vmbus connection rather
 274          * than the channel to establish the gpadl handle.
 275          */
 276         ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
 277                                     net_device->recv_buf_size,
 278                                     &net_device->recv_buf_gpadl_handle);
 279         if (ret != 0) {
 280                 netdev_err(ndev,
 281                         "unable to establish receive buffer's gpadl\n");
 282                 goto cleanup;
 283         }
 284
 285         /* Notify the NetVsp of the gpadl handle */
 286         init_packet = &net_device->channel_init_pkt;
 287
 288         memset(init_packet, 0, sizeof(struct nvsp_message));
 289
 290         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 291         init_packet->msg.v1_msg.send_recv_buf.
 292                 gpadl_handle = net_device->recv_buf_gpadl_handle;
 293         init_packet->msg.v1_msg.
 294                 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 295
 296         /* Send the gpadl notification request */
 297         ret = vmbus_sendpacket(device->channel, init_packet,
 298                                sizeof(struct nvsp_message),
 299                                (unsigned long)init_packet,
 300                                VM_PKT_DATA_INBAND,
 301                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 302         if (ret != 0) {
 303                 netdev_err(ndev,
 304                         "unable to send receive buffer's gpadl to netvsp\n");
 305                 goto cleanup;
 306         }
 307
 308         wait_for_completion(&net_device->channel_init_wait);
 309
 310         /* Check the response */
 311         if (init_packet->msg.v1_msg.
 312             send_recv_buf_complete.status != NVSP_STAT_SUCCESS) {
 313                 netdev_err(ndev, "Unable to complete receive buffer "
 314                            "initialization with NetVsp - status %d\n",
 315                            init_packet->msg.v1_msg.
 316                            send_recv_buf_complete.status);
 317                 ret = -EINVAL;
 318                 goto cleanup;
 319         }
 320
 321         /* Parse the response */
 322
 323         net_device->recv_section_cnt = init_packet->msg.
 324                 v1_msg.send_recv_buf_complete.num_sections;
 325
 326         net_device->recv_section = kmemdup(
 327                 init_packet->msg.v1_msg.send_recv_buf_complete.sections,
 328                 net_device->recv_section_cnt *
 329                 sizeof(struct nvsp_1_receive_buffer_section),
 330                 GFP_KERNEL);
 331         if (net_device->recv_section == NULL) {
 332                 ret = -EINVAL;
 333                 goto cleanup;
 334         }
 335
 336         /*
 337          * For 1st release, there should only be 1 section that represents the
 338          * entire receive buffer
 339          */
 340         if (net_device->recv_section_cnt != 1 ||
 341             net_device->recv_section->offset != 0) {
 342                 ret = -EINVAL;
 343                 goto cleanup;
 344         }
 345
 346         /* Now setup the send buffer.
 347          */
 348         net_device->send_buf = vzalloc_node(net_device->send_buf_size, node);
 349         if (!net_device->send_buf)
 350                 net_device->send_buf = vzalloc(net_device->send_buf_size);
 351         if (!net_device->send_buf) {
 352                 netdev_err(ndev, "unable to allocate send "
 353                            "buffer of size %d\n", net_device->send_buf_size);
 354                 ret = -ENOMEM;
 355                 goto cleanup;
 356         }
 357
 358         /* Establish the gpadl handle for this buffer on this
 359          * channel.  Note: This call uses the vmbus connection rather
 360          * than the channel to establish the gpadl handle.
 361          */
 362         ret = vmbus_establish_gpadl(device->channel, net_device->send_buf,
 363                                     net_device->send_buf_size,
 364                                     &net_device->send_buf_gpadl_handle);
 365         if (ret != 0) {
 366                 netdev_err(ndev,
 367                            "unable to establish send buffer's gpadl\n");
 368                 goto cleanup;
 369         }
 370
 371         /* Notify the NetVsp of the gpadl handle */
 372         init_packet = &net_device->channel_init_pkt;
 373         memset(init_packet, 0, sizeof(struct nvsp_message));
 374         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
 375         init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
 376                 net_device->send_buf_gpadl_handle;
 377         init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;
 378
 379         /* Send the gpadl notification request */
 380         ret = vmbus_sendpacket(device->channel, init_packet,
 381                                sizeof(struct nvsp_message),
 382                                (unsigned long)init_packet,
 383                                VM_PKT_DATA_INBAND,
 384                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 385         if (ret != 0) {
 386                 netdev_err(ndev,
 387                            "unable to send send buffer's gpadl to netvsp\n");
 388                 goto cleanup;
 389         }
 390
 391         wait_for_completion(&net_device->channel_init_wait);
 392
 393         /* Check the response */
 394         if (init_packet->msg.v1_msg.
 395             send_send_buf_complete.status != NVSP_STAT_SUCCESS) {
 396                 netdev_err(ndev, "Unable to complete send buffer "
 397                            "initialization with NetVsp - status %d\n",
 398                            init_packet->msg.v1_msg.
 399                            send_send_buf_complete.status);
 400                 ret = -EINVAL;
 401                 goto cleanup;
 402         }
 403
 404         /* Parse the response */
 405         net_device->send_section_size = init_packet->msg.
 406                                 v1_msg.send_send_buf_complete.section_size;
 407
 408         /* Section count is simply the size divided by the section size.
 409          */
 410         net_device->send_section_cnt =
 411                 net_device->send_buf_size / net_device->send_section_size;
 412
 413         dev_info(&device->device, "Send section size: %d, Section count:%d\n",
 414                  net_device->send_section_size, net_device->send_section_cnt);
 415
 416         /* Setup state for managing the send buffer. */
 417         net_device->map_words = DIV_ROUND_UP(net_device->send_section_cnt,
 418                                              BITS_PER_LONG);
 419
 420         net_device->send_section_map = kcalloc(net_device->map_words,
 421                                                sizeof(ulong), GFP_KERNEL);
 422         if (net_device->send_section_map == NULL) {
 423                 ret = -ENOMEM;
 424                 goto cleanup;
 425         }
 426
 427         goto exit;
 428
 429 cleanup:
 430         netvsc_destroy_buf(device);
 431
 432 exit:
 433         return ret;
 434 }
 435
 436 /* Negotiate NVSP protocol version */
 437 static int negotiate_nvsp_ver(struct hv_device *device,
 438                               struct netvsc_device *net_device,
 439                               struct nvsp_message *init_packet,
 440                               u32 nvsp_ver)
 441 {
 442         struct net_device *ndev = hv_get_drvdata(device);
 443         int ret;
 444
 445         memset(init_packet, 0, sizeof(struct nvsp_message));
 446         init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
 447         init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
 448         init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
 449
 450         /* Send the init request */
 451         ret = vmbus_sendpacket(device->channel, init_packet,
 452                                sizeof(struct nvsp_message),
 453                                (unsigned long)init_packet,
 454                                VM_PKT_DATA_INBAND,
 455                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 456
 457         if (ret != 0)
 458                 return ret;
 459
 460         wait_for_completion(&net_device->channel_init_wait);
 461
 462         if (init_packet->msg.init_msg.init_complete.status !=
 463             NVSP_STAT_SUCCESS)
 464                 return -EINVAL;
 465
 466         if (nvsp_ver == NVSP_PROTOCOL_VERSION_1)
 467                 return 0;
 468
 469         /* NVSPv2 or later: Send NDIS config */
 470         memset(init_packet, 0, sizeof(struct nvsp_message));
 471         init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
 472         init_packet->msg.v2_msg.send_ndis_config.mtu = ndev->mtu + ETH_HLEN;
 473         init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
 474
 475         if (nvsp_ver >= NVSP_PROTOCOL_VERSION_5) {
 476                 init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
 477
 478                 /* Teaming bit is needed to receive link speed updates */
 479                 init_packet->msg.v2_msg.send_ndis_config.capability.teaming = 1;
 480         }
 481
 482         ret = vmbus_sendpacket(device->channel, init_packet,
 483                                 sizeof(struct nvsp_message),
 484                                 (unsigned long)init_packet,
 485                                 VM_PKT_DATA_INBAND, 0);
 486
 487         return ret;
 488 }
 489
 490 static int netvsc_connect_vsp(struct hv_device *device)
 491 {
 492         int ret;
 493         struct netvsc_device *net_device;
 494         struct nvsp_message *init_packet;
 495         int ndis_version;
 496         const u32 ver_list[] = {
 497                 NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
 498                 NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5 };
 499         int i;
 500
 501         net_device = get_outbound_net_device(device);
 502         if (!net_device)
 503                 return -ENODEV;
 504
 505         init_packet = &net_device->channel_init_pkt;
 506
 507         /* Negotiate the latest NVSP protocol supported */
 508         for (i = ARRAY_SIZE(ver_list) - 1; i >= 0; i--)
 509                 if (negotiate_nvsp_ver(device, net_device, init_packet,
 510                                        ver_list[i])  == 0) {
 511                         net_device->nvsp_version = ver_list[i];
 512                         break;
 513                 }
 514
 515         if (i < 0) {
 516                 ret = -EPROTO;
 517                 goto cleanup;
 518         }
 519
 520         pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
 521
 522         /* Send the ndis version */
 523         memset(init_packet, 0, sizeof(struct nvsp_message));
 524
 525         if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_4)
 526                 ndis_version = 0x00060001;
 527         else
 528                 ndis_version = 0x0006001e;
 529
 530         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
 531         init_packet->msg.v1_msg.
 532                 send_ndis_ver.ndis_major_ver =
 533                                 (ndis_version & 0xFFFF0000) >> 16;
 534         init_packet->msg.v1_msg.
 535                 send_ndis_ver.ndis_minor_ver =
 536                                 ndis_version & 0xFFFF;
 537
 538         /* Send the init request */
 539         ret = vmbus_sendpacket(device->channel, init_packet,
 540                                 sizeof(struct nvsp_message),
 541                                 (unsigned long)init_packet,
 542                                 VM_PKT_DATA_INBAND, 0);
 543         if (ret != 0)
 544                 goto cleanup;
 545
 546         /* Post the big receive buffer to NetVSP */
 547         if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
 548                 net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
 549         else
 550                 net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
 551         net_device->send_buf_size = NETVSC_SEND_BUFFER_SIZE;
 552
 553         ret = netvsc_init_buf(device);
 554
 555 cleanup:
 556         return ret;
 557 }
 558
 559 static void netvsc_disconnect_vsp(struct hv_device *device)
 560 {
 561         netvsc_destroy_buf(device);
 562 }
 563
 564 /*
 565  * netvsc_device_remove - Callback when the root bus device is removed
 566  */
 567 void netvsc_device_remove(struct hv_device *device)
 568 {
 569         struct net_device *ndev = hv_get_drvdata(device);
 570         struct net_device_context *net_device_ctx = netdev_priv(ndev);
 571         struct netvsc_device *net_device = net_device_ctx->nvdev;
 572
 573         netvsc_disconnect_vsp(device);
 574
 575         net_device_ctx->nvdev = NULL;
 576
 577         /*
 578          * At this point, no one should be accessing net_device
 579          * except in here
 580          */
 581         dev_notice(&device->device, "net device safe to remove\n");
 582
 583         /* Now, we can close the channel safely */
 584         vmbus_close(device->channel);
 585
 586         /* Release all resources */
 587         vfree(net_device->sub_cb_buf);
 588         free_netvsc_device(net_device);
 589 }
 590
 591 #define RING_AVAIL_PERCENT_HIWATER 20
 592 #define RING_AVAIL_PERCENT_LOWATER 10
 593
 594 /*
 595  * Get the percentage of available bytes to write in the ring.
 596  * The return value is in range from 0 to 100.
 597  */
 598 static inline u32 hv_ringbuf_avail_percent(
 599                 struct hv_ring_buffer_info *ring_info)
 600 {
 601         u32 avail_read, avail_write;
 602
 603         hv_get_ringbuffer_availbytes(ring_info, &avail_read, &avail_write);
 604
 605         return avail_write * 100 / ring_info->ring_datasize;
 606 }
 607
 608 static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
 609                                          u32 index)
 610 {
 611         sync_change_bit(index, net_device->send_section_map);
 612 }
 613
 614 static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 615                                     struct vmbus_channel *incoming_channel,
 616                                     struct hv_device *device,
 617                                     struct vmpacket_descriptor *packet)
 618 {
 619         struct sk_buff *skb = (struct sk_buff *)(unsigned long)packet->trans_id;
 620         struct net_device *ndev = hv_get_drvdata(device);
 621         struct net_device_context *net_device_ctx = netdev_priv(ndev);
 622         struct vmbus_channel *channel = device->channel;
 623         int num_outstanding_sends;
 624         u16 q_idx = 0;
 625         int queue_sends;
 626
 627         /* Notify the layer above us */
 628         if (likely(skb)) {
 629                 struct hv_netvsc_packet *nvsc_packet
 630                         = (struct hv_netvsc_packet *)skb->cb;
 631                 u32 send_index = nvsc_packet->send_buf_index;
 632
 633                 if (send_index != NETVSC_INVALID_INDEX)
 634                         netvsc_free_send_slot(net_device, send_index);
 635                 q_idx = nvsc_packet->q_idx;
 636                 channel = incoming_channel;
 637
 638                 dev_consume_skb_any(skb);
 639         }
 640
 641         num_outstanding_sends =
 642                 atomic_dec_return(&net_device->num_outstanding_sends);
 643         queue_sends = atomic_dec_return(&net_device->queue_sends[q_idx]);
 644
 645         if (net_device->destroy && num_outstanding_sends == 0)
 646                 wake_up(&net_device->wait_drain);
 647
 648         if (netif_tx_queue_stopped(netdev_get_tx_queue(ndev, q_idx)) &&
 649             !net_device_ctx->start_remove &&
 650             (hv_ringbuf_avail_percent(&channel->outbound) > RING_AVAIL_PERCENT_HIWATER ||
 651              queue_sends < 1))
 652                 netif_tx_wake_queue(netdev_get_tx_queue(ndev, q_idx));
 653 }
 654
 655 static void netvsc_send_completion(struct netvsc_device *net_device,
 656                                    struct vmbus_channel *incoming_channel,
 657                                    struct hv_device *device,
 658                                    struct vmpacket_descriptor *packet)
 659 {
 660         struct nvsp_message *nvsp_packet;
 661         struct net_device *ndev = hv_get_drvdata(device);
 662
 663         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 664                                               (packet->offset8 << 3));
 665
 666         switch (nvsp_packet->hdr.msg_type) {
 667         case NVSP_MSG_TYPE_INIT_COMPLETE:
 668         case NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE:
 669         case NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE:
 670         case NVSP_MSG5_TYPE_SUBCHANNEL:
 671                 /* Copy the response back */
 672                 memcpy(&net_device->channel_init_pkt, nvsp_packet,
 673                        sizeof(struct nvsp_message));
 674                 complete(&net_device->channel_init_wait);
 675                 break;
 676
 677         case NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE:
 678                 netvsc_send_tx_complete(net_device, incoming_channel,
 679                                         device, packet);
 680                 break;
 681
 682         default:
 683                 netdev_err(ndev,
 684                            "Unknown send completion type %d received!!\n",
 685                            nvsp_packet->hdr.msg_type);
 686         }
 687 }
 688
 689 static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
 690 {
 691         unsigned long index;
 692         u32 max_words = net_device->map_words;
 693         unsigned long *map_addr = (unsigned long *)net_device->send_section_map;
 694         u32 section_cnt = net_device->send_section_cnt;
 695         int ret_val = NETVSC_INVALID_INDEX;
 696         int i;
 697         int prev_val;
 698
 699         for (i = 0; i < max_words; i++) {
 700                 if (!~(map_addr[i]))
 701                         continue;
 702                 index = ffz(map_addr[i]);
 703                 prev_val = sync_test_and_set_bit(index, &map_addr[i]);
 704                 if (prev_val)
 705                         continue;
 706                 if ((index + (i * BITS_PER_LONG)) >= section_cnt)
 707                         break;
 708                 ret_val = (index + (i * BITS_PER_LONG));
 709                 break;
 710         }
 711         return ret_val;
 712 }
 713
 714 static u32 netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 715                                    unsigned int section_index,
 716                                    u32 pend_size,
 717                                    struct hv_netvsc_packet *packet,
 718                                    struct rndis_message *rndis_msg,
 719                                    struct hv_page_buffer **pb,
 720                                    struct sk_buff *skb)
 721 {
 722         char *start = net_device->send_buf;
 723         char *dest = start + (section_index * net_device->send_section_size)
 724                      + pend_size;
 725         int i;
 726         bool is_data_pkt = (skb != NULL) ? true : false;
 727         bool xmit_more = (skb != NULL) ? skb->xmit_more : false;
 728         u32 msg_size = 0;
 729         u32 padding = 0;
 730         u32 remain = packet->total_data_buflen % net_device->pkt_align;
 731         u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
 732                 packet->page_buf_cnt;
 733
 734         /* Add padding */
 735         if (is_data_pkt && xmit_more && remain &&
 736             !packet->cp_partial) {
 737                 padding = net_device->pkt_align - remain;
 738                 rndis_msg->msg_len += padding;
 739                 packet->total_data_buflen += padding;
 740         }
 741
 742         for (i = 0; i < page_count; i++) {
 743                 char *src = phys_to_virt((*pb)[i].pfn << PAGE_SHIFT);
 744                 u32 offset = (*pb)[i].offset;
 745                 u32 len = (*pb)[i].len;
 746
 747                 memcpy(dest, (src + offset), len);
 748                 msg_size += len;
 749                 dest += len;
 750         }
 751
 752         if (padding) {
 753                 memset(dest, 0, padding);
 754                 msg_size += padding;
 755         }
 756
 757         return msg_size;
 758 }
 759
 760 static inline int netvsc_send_pkt(
 761         struct hv_device *device,
 762         struct hv_netvsc_packet *packet,
 763         struct netvsc_device *net_device,
 764         struct hv_page_buffer **pb,
 765         struct sk_buff *skb)
 766 {
 767         struct nvsp_message nvmsg;
 768         u16 q_idx = packet->q_idx;
 769         struct vmbus_channel *out_channel = net_device->chn_table[q_idx];
 770         struct net_device *ndev = hv_get_drvdata(device);
 771         u64 req_id;
 772         int ret;
 773         struct hv_page_buffer *pgbuf;
 774         u32 ring_avail = hv_ringbuf_avail_percent(&out_channel->outbound);
 775         bool xmit_more = (skb != NULL) ? skb->xmit_more : false;
 776
 777         nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 778         if (skb != NULL) {
 779                 /* 0 is RMC_DATA; */
 780                 nvmsg.msg.v1_msg.send_rndis_pkt.channel_type = 0;
 781         } else {
 782                 /* 1 is RMC_CONTROL; */
 783                 nvmsg.msg.v1_msg.send_rndis_pkt.channel_type = 1;
 784         }
 785
 786         nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_index =
 787                 packet->send_buf_index;
 788         if (packet->send_buf_index == NETVSC_INVALID_INDEX)
 789                 nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_size = 0;
 790         else
 791                 nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_size =
 792                         packet->total_data_buflen;
 793
 794         req_id = (ulong)skb;
 795
 796         if (out_channel->rescind)
 797                 return -ENODEV;
 798
 799         /*
 800          * It is possible that once we successfully place this packet
 801          * on the ringbuffer, we may stop the queue. In that case, we want
 802          * to notify the host independent of the xmit_more flag. We don't
 803          * need to be precise here; in the worst case we may signal the host
 804          * unnecessarily.
 805          */
 806         if (ring_avail < (RING_AVAIL_PERCENT_LOWATER + 1))
 807                 xmit_more = false;
 808
 809         if (packet->page_buf_cnt) {
 810                 pgbuf = packet->cp_partial ? (*pb) +
 811                         packet->rmsg_pgcnt : (*pb);
 812                 ret = vmbus_sendpacket_pagebuffer_ctl(out_channel,
 813                                                       pgbuf,
 814                                                       packet->page_buf_cnt,
 815                                                       &nvmsg,
 816                                                       sizeof(struct nvsp_message),
 817                                                       req_id,
 818                                                       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED,
 819                                                       !xmit_more);
 820         } else {
 821                 ret = vmbus_sendpacket_ctl(out_channel, &nvmsg,
 822                                            sizeof(struct nvsp_message),
 823                                            req_id,
 824                                            VM_PKT_DATA_INBAND,
 825                                            VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED,
 826                                            !xmit_more);
 827         }
 828
 829         if (ret == 0) {
 830                 atomic_inc(&net_device->num_outstanding_sends);
 831                 atomic_inc(&net_device->queue_sends[q_idx]);
 832
 833                 if (ring_avail < RING_AVAIL_PERCENT_LOWATER) {
 834                         netif_tx_stop_queue(netdev_get_tx_queue(ndev, q_idx));
 835
 836                         if (atomic_read(&net_device->
 837                                 queue_sends[q_idx]) < 1)
 838                                 netif_tx_wake_queue(netdev_get_tx_queue(
 839                                                     ndev, q_idx));
 840                 }
 841         } else if (ret == -EAGAIN) {
 842                 netif_tx_stop_queue(netdev_get_tx_queue(
 843                                     ndev, q_idx));
 844                 if (atomic_read(&net_device->queue_sends[q_idx]) < 1) {
 845                         netif_tx_wake_queue(netdev_get_tx_queue(
 846                                             ndev, q_idx));
 847                         ret = -ENOSPC;
 848                 }
 849         } else {
 850                 netdev_err(ndev, "Unable to send packet %p ret %d\n",
 851                            packet, ret);
 852         }
 853
 854         return ret;
 855 }
 856
 857 /* Move packet out of multi send data (msd), and clear msd */
 858 static inline void move_pkt_msd(struct hv_netvsc_packet **msd_send,
 859                                 struct sk_buff **msd_skb,
 860                                 struct multi_send_data *msdp)
 861 {
 862         *msd_skb = msdp->skb;
 863         *msd_send = msdp->pkt;
 864         msdp->skb = NULL;
 865         msdp->pkt = NULL;
 866         msdp->count = 0;
 867 }
 868
 869 int netvsc_send(struct hv_device *device,
 870                 struct hv_netvsc_packet *packet,
 871                 struct rndis_message *rndis_msg,
 872                 struct hv_page_buffer **pb,
 873                 struct sk_buff *skb)
 874 {
 875         struct netvsc_device *net_device;
 876         int ret = 0;
 877         struct vmbus_channel *out_channel;
 878         u16 q_idx = packet->q_idx;
 879         u32 pktlen = packet->total_data_buflen, msd_len = 0;
 880         unsigned int section_index = NETVSC_INVALID_INDEX;
 881         struct multi_send_data *msdp;
 882         struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
 883         struct sk_buff *msd_skb = NULL;
 884         bool try_batch;
 885         bool xmit_more = (skb != NULL) ? skb->xmit_more : false;
 886
 887         net_device = get_outbound_net_device(device);
 888         if (!net_device)
 889                 return -ENODEV;
 890
 891         out_channel = net_device->chn_table[q_idx];
 892
 893         packet->send_buf_index = NETVSC_INVALID_INDEX;
 894         packet->cp_partial = false;
 895
 896         /* Send control message directly without accessing msd (Multi-Send
 897          * Data) field which may be changed during data packet processing.
 898          */
 899         if (!skb) {
 900                 cur_send = packet;
 901                 goto send_now;
 902         }
 903
 904         msdp = &net_device->msd[q_idx];
 905
 906         /* batch packets in send buffer if possible */
 907         if (msdp->pkt)
 908                 msd_len = msdp->pkt->total_data_buflen;
 909
 910         try_batch = (skb != NULL) && msd_len > 0 && msdp->count <
 911                     net_device->max_pkt;
 912
 913         if (try_batch && msd_len + pktlen + net_device->pkt_align <
 914             net_device->send_section_size) {
 915                 section_index = msdp->pkt->send_buf_index;
 916
 917         } else if (try_batch && msd_len + packet->rmsg_size <
 918                    net_device->send_section_size) {
 919                 section_index = msdp->pkt->send_buf_index;
 920                 packet->cp_partial = true;
 921
 922         } else if ((skb != NULL) && pktlen + net_device->pkt_align <
 923                    net_device->send_section_size) {
 924                 section_index = netvsc_get_next_send_section(net_device);
 925                 if (section_index != NETVSC_INVALID_INDEX) {
 926                         move_pkt_msd(&msd_send, &msd_skb, msdp);
 927                         msd_len = 0;
 928                 }
 929         }
 930
 931         if (section_index != NETVSC_INVALID_INDEX) {
 932                 netvsc_copy_to_send_buf(net_device,
 933                                         section_index, msd_len,
 934                                         packet, rndis_msg, pb, skb);
 935
 936                 packet->send_buf_index = section_index;
 937
 938                 if (packet->cp_partial) {
 939                         packet->page_buf_cnt -= packet->rmsg_pgcnt;
 940                         packet->total_data_buflen = msd_len + packet->rmsg_size;
 941                 } else {
 942                         packet->page_buf_cnt = 0;
 943                         packet->total_data_buflen += msd_len;
 944                 }
 945
 946                 if (msdp->skb)
 947                         dev_consume_skb_any(msdp->skb);
 948
 949                 if (xmit_more && !packet->cp_partial) {
 950                         msdp->skb = skb;
 951                         msdp->pkt = packet;
 952                         msdp->count++;
 953                 } else {
 954                         cur_send = packet;
 955                         msdp->skb = NULL;
 956                         msdp->pkt = NULL;
 957                         msdp->count = 0;
 958                 }
 959         } else {
 960                 move_pkt_msd(&msd_send, &msd_skb, msdp);
 961                 cur_send = packet;
 962         }
 963
 964         if (msd_send) {
 965                 int m_ret = netvsc_send_pkt(device, msd_send, net_device,
 966                                             NULL, msd_skb);
 967
 968                 if (m_ret != 0) {
 969                         netvsc_free_send_slot(net_device,
 970                                               msd_send->send_buf_index);
 971                         dev_kfree_skb_any(msd_skb);
 972                 }
 973         }
 974
 975 send_now:
 976         if (cur_send)
 977                 ret = netvsc_send_pkt(device, cur_send, net_device, pb, skb);
 978
 979         if (ret != 0 && section_index != NETVSC_INVALID_INDEX)
 980                 netvsc_free_send_slot(net_device, section_index);
 981
 982         return ret;
 983 }
 984
 985 static int netvsc_send_recv_completion(struct vmbus_channel *channel,
 986                                        u64 transaction_id, u32 status)
 987 {
 988         struct nvsp_message recvcompMessage;
 989         int ret;
 990
 991         recvcompMessage.hdr.msg_type =
 992                                 NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE;
 993
 994         recvcompMessage.msg.v1_msg.send_rndis_pkt_complete.status = status;
 995
 996         /* Send the completion */
 997         ret = vmbus_sendpacket(channel, &recvcompMessage,
 998                                sizeof(struct nvsp_message_header) + sizeof(u32),
 999                                transaction_id, VM_PKT_COMP, 0);
1000
1001         return ret;
1002 }
1003
1004 static inline void count_recv_comp_slot(struct netvsc_device *nvdev, u16 q_idx,
1005                                         u32 *filled, u32 *avail)
1006 {
1007         u32 first = nvdev->mrc[q_idx].first;
1008         u32 next = nvdev->mrc[q_idx].next;
1009
1010         *filled = (first > next) ? NETVSC_RECVSLOT_MAX - first + next :
1011                   next - first;
1012
1013         *avail = NETVSC_RECVSLOT_MAX - *filled - 1;
1014 }
1015
1016 /* Read the first filled slot, no change to index */
1017 static inline struct recv_comp_data *read_recv_comp_slot(struct netvsc_device
1018                                                          *nvdev, u16 q_idx)
1019 {
1020         u32 filled, avail;
1021
1022         if (!nvdev->mrc[q_idx].buf)
1023                 return NULL;
1024
1025         count_recv_comp_slot(nvdev, q_idx, &filled, &avail);
1026         if (!filled)
1027                 return NULL;
1028
1029         return nvdev->mrc[q_idx].buf + nvdev->mrc[q_idx].first *
1030                sizeof(struct recv_comp_data);
1031 }
1032
1033 /* Put the first filled slot back to available pool */
1034 static inline void put_recv_comp_slot(struct netvsc_device *nvdev, u16 q_idx)
1035 {
1036         int num_recv;
1037
1038         nvdev->mrc[q_idx].first = (nvdev->mrc[q_idx].first + 1) %
1039                                   NETVSC_RECVSLOT_MAX;
1040
1041         num_recv = atomic_dec_return(&nvdev->num_outstanding_recvs);
1042
1043         if (nvdev->destroy && num_recv == 0)
1044                 wake_up(&nvdev->wait_drain);
1045 }
1046
1047 /* Check and send pending recv completions */
1048 static void netvsc_chk_recv_comp(struct netvsc_device *nvdev,
1049                                  struct vmbus_channel *channel, u16 q_idx)
1050 {
1051         struct recv_comp_data *rcd;
1052         int ret;
1053
1054         while (true) {
1055                 rcd = read_recv_comp_slot(nvdev, q_idx);
1056                 if (!rcd)
1057                         break;
1058
1059                 ret = netvsc_send_recv_completion(channel, rcd->tid,
1060                                                   rcd->status);
1061                 if (ret)
1062                         break;
1063
1064                 put_recv_comp_slot(nvdev, q_idx);
1065         }
1066 }
1067
1068 #define NETVSC_RCD_WATERMARK 80
1069
1070 /* Get next available slot */
1071 static inline struct recv_comp_data *get_recv_comp_slot(
1072         struct netvsc_device *nvdev, struct vmbus_channel *channel, u16 q_idx)
1073 {
1074         u32 filled, avail, next;
1075         struct recv_comp_data *rcd;
1076
1077         if (!nvdev->recv_section)
1078                 return NULL;
1079
1080         if (!nvdev->mrc[q_idx].buf)
1081                 return NULL;
1082
1083         if (atomic_read(&nvdev->num_outstanding_recvs) >
1084             nvdev->recv_section->num_sub_allocs * NETVSC_RCD_WATERMARK / 100)
1085                 netvsc_chk_recv_comp(nvdev, channel, q_idx);
1086
1087         count_recv_comp_slot(nvdev, q_idx, &filled, &avail);
1088         if (!avail)
1089                 return NULL;
1090
1091         next = nvdev->mrc[q_idx].next;
1092         rcd = nvdev->mrc[q_idx].buf + next * sizeof(struct recv_comp_data);
1093         nvdev->mrc[q_idx].next = (next + 1) % NETVSC_RECVSLOT_MAX;
1094
1095         atomic_inc(&nvdev->num_outstanding_recvs);
1096
1097         return rcd;
1098 }
1099
1100 static void netvsc_receive(struct netvsc_device *net_device,
1101                         struct vmbus_channel *channel,
1102                         struct hv_device *device,
1103                         struct vmpacket_descriptor *packet)
1104 {
1105         struct vmtransfer_page_packet_header *vmxferpage_packet;
1106         struct nvsp_message *nvsp_packet;
1107         struct hv_netvsc_packet nv_pkt;
1108         struct hv_netvsc_packet *netvsc_packet = &nv_pkt;
1109         u32 status = NVSP_STAT_SUCCESS;
1110         int i;
1111         int count = 0;
1112         struct net_device *ndev = hv_get_drvdata(device);
1113         void *data;
1114         int ret;
1115         struct recv_comp_data *rcd;
1116         u16 q_idx = channel->offermsg.offer.sub_channel_index;
1117
1118         /*
1119          * All inbound packets other than send completion should be xfer page
1120          * packet
1121          */
1122         if (packet->type != VM_PKT_DATA_USING_XFER_PAGES) {
1123                 netdev_err(ndev, "Unknown packet type received - %d\n",
1124                            packet->type);
1125                 return;
1126         }
1127
1128         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
1129                         (packet->offset8 << 3));
1130
1131         /* Make sure this is a valid nvsp packet */
1132         if (nvsp_packet->hdr.msg_type !=
1133             NVSP_MSG1_TYPE_SEND_RNDIS_PKT) {
1134                 netdev_err(ndev, "Unknown nvsp packet type received-"
1135                         " %d\n", nvsp_packet->hdr.msg_type);
1136                 return;
1137         }
1138
1139         vmxferpage_packet = (struct vmtransfer_page_packet_header *)packet;
1140
1141         if (vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID) {
1142                 netdev_err(ndev, "Invalid xfer page set id - "
1143                            "expecting %x got %x\n", NETVSC_RECEIVE_BUFFER_ID,
1144                            vmxferpage_packet->xfer_pageset_id);
1145                 return;
1146         }
1147
1148         count = vmxferpage_packet->range_cnt;
1149
1150         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1151         for (i = 0; i < count; i++) {
1152                 /* Initialize the netvsc packet */
1153                 data = (void *)((unsigned long)net_device->
1154                         recv_buf + vmxferpage_packet->ranges[i].byte_offset);
1155                 netvsc_packet->total_data_buflen =
1156                                         vmxferpage_packet->ranges[i].byte_count;
1157
1158                 /* Pass it to the upper layer */
1159                 status = rndis_filter_receive(device, netvsc_packet, &data,
1160                                               channel);
1161         }
1162
1163         if (!net_device->mrc[q_idx].buf) {
1164                 ret = netvsc_send_recv_completion(channel,
1165                                                   vmxferpage_packet->d.trans_id,
1166                                                   status);
1167                 if (ret)
1168                         netdev_err(ndev, "Recv_comp q:%hd, tid:%llx, err:%d\n",
1169                                    q_idx, vmxferpage_packet->d.trans_id, ret);
1170                 return;
1171         }
1172
1173         rcd = get_recv_comp_slot(net_device, channel, q_idx);
1174
1175         if (!rcd) {
1176                 netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",
1177                            q_idx, vmxferpage_packet->d.trans_id);
1178                 return;
1179         }
1180
1181         rcd->tid = vmxferpage_packet->d.trans_id;
1182         rcd->status = status;
1183 }
1184
1185 static void netvsc_send_table(struct hv_device *hdev,
1186                               struct nvsp_message *nvmsg)
1187 {
1188         struct netvsc_device *nvscdev;
1189         struct net_device *ndev = hv_get_drvdata(hdev);
1190         int i;
1191         u32 count, *tab;
1192
1193         nvscdev = get_outbound_net_device(hdev);
1194         if (!nvscdev)
1195                 return;
1196
1197         count = nvmsg->msg.v5_msg.send_table.count;
1198         if (count != VRSS_SEND_TAB_SIZE) {
1199                 netdev_err(ndev, "Received wrong send-table size:%u\n", count);
1200                 return;
1201         }
1202
1203         tab = (u32 *)((unsigned long)&nvmsg->msg.v5_msg.send_table +
1204                       nvmsg->msg.v5_msg.send_table.offset);
1205
1206         for (i = 0; i < count; i++)
1207                 nvscdev->send_table[i] = tab[i];
1208 }
1209
1210 static void netvsc_send_vf(struct net_device_context *net_device_ctx,
1211                            struct nvsp_message *nvmsg)
1212 {
1213         net_device_ctx->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated;
1214         net_device_ctx->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial;
1215 }
1216
1217 static inline void netvsc_receive_inband(struct hv_device *hdev,
1218                                  struct net_device_context *net_device_ctx,
1219                                  struct nvsp_message *nvmsg)
1220 {
1221         switch (nvmsg->hdr.msg_type) {
1222         case NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE:
1223                 netvsc_send_table(hdev, nvmsg);
1224                 break;
1225
1226         case NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION:
1227                 netvsc_send_vf(net_device_ctx, nvmsg);
1228                 break;
1229         }
1230 }
1231
1232 static void netvsc_process_raw_pkt(struct hv_device *device,
1233                                    struct vmbus_channel *channel,
1234                                    struct netvsc_device *net_device,
1235                                    struct net_device *ndev,
1236                                    u64 request_id,
1237                                    struct vmpacket_descriptor *desc)
1238 {
1239         struct nvsp_message *nvmsg;
1240         struct net_device_context *net_device_ctx = netdev_priv(ndev);
1241
1242         nvmsg = (struct nvsp_message *)((unsigned long)
1243                 desc + (desc->offset8 << 3));
1244
1245         switch (desc->type) {
1246         case VM_PKT_COMP:
1247                 netvsc_send_completion(net_device, channel, device, desc);
1248                 break;
1249
1250         case VM_PKT_DATA_USING_XFER_PAGES:
1251                 netvsc_receive(net_device, channel, device, desc);
1252                 break;
1253
1254         case VM_PKT_DATA_INBAND:
1255                 netvsc_receive_inband(device, net_device_ctx, nvmsg);
1256                 break;
1257
1258         default:
1259                 netdev_err(ndev, "unhandled packet type %d, tid %llx\n",
1260                            desc->type, request_id);
1261                 break;
1262         }
1263 }
1264
1265 void netvsc_channel_cb(void *context)
1266 {
1267         int ret;
1268         struct vmbus_channel *channel = (struct vmbus_channel *)context;
1269         u16 q_idx = channel->offermsg.offer.sub_channel_index;
1270         struct hv_device *device;
1271         struct netvsc_device *net_device;
1272         u32 bytes_recvd;
1273         u64 request_id;
1274         struct vmpacket_descriptor *desc;
1275         unsigned char *buffer;
1276         int bufferlen = NETVSC_PACKET_SIZE;
1277         struct net_device *ndev;
1278         bool need_to_commit = false;
1279
1280         if (channel->primary_channel != NULL)
1281                 device = channel->primary_channel->device_obj;
1282         else
1283                 device = channel->device_obj;
1284
1285         net_device = get_inbound_net_device(device);
1286         if (!net_device)
1287                 return;
1288         ndev = hv_get_drvdata(device);
1289         buffer = get_per_channel_state(channel);
1290
1291         do {
1292                 desc = get_next_pkt_raw(channel);
1293                 if (desc != NULL) {
1294                         netvsc_process_raw_pkt(device,
1295                                                channel,
1296                                                net_device,
1297                                                ndev,
1298                                                desc->trans_id,
1299                                                desc);
1300
1301                         put_pkt_raw(channel, desc);
1302                         need_to_commit = true;
1303                         continue;
1304                 }
1305                 if (need_to_commit) {
1306                         need_to_commit = false;
1307                         commit_rd_index(channel);
1308                 }
1309
1310                 ret = vmbus_recvpacket_raw(channel, buffer, bufferlen,
1311                                            &bytes_recvd, &request_id);
1312                 if (ret == 0) {
1313                         if (bytes_recvd > 0) {
1314                                 desc = (struct vmpacket_descriptor *)buffer;
1315                                 netvsc_process_raw_pkt(device,
1316                                                        channel,
1317                                                        net_device,
1318                                                        ndev,
1319                                                        request_id,
1320                                                        desc);
1321                         } else {
1322                                 /*
1323                                  * We are done for this pass.
1324                                  */
1325                                 break;
1326                         }
1327
1328                 } else if (ret == -ENOBUFS) {
1329                         if (bufferlen > NETVSC_PACKET_SIZE)
1330                                 kfree(buffer);
1331                         /* Handle large packet */
1332                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
1333                         if (buffer == NULL) {
1334                                 /* Try again next time around */
1335                                 netdev_err(ndev,
1336                                            "unable to allocate buffer of size "
1337                                            "(%d)!!\n", bytes_recvd);
1338                                 break;
1339                         }
1340
1341                         bufferlen = bytes_recvd;
1342                 }
1343         } while (1);
1344
1345         if (bufferlen > NETVSC_PACKET_SIZE)
1346                 kfree(buffer);
1347
1348         netvsc_chk_recv_comp(net_device, channel, q_idx);
1349 }
1350
1351 /*
1352  * netvsc_device_add - Callback when the device belonging to this
1353  * driver is added
1354  */
1355 int netvsc_device_add(struct hv_device *device, void *additional_info)
1356 {
1357         int i, ret = 0;
1358         int ring_size =
1359         ((struct netvsc_device_info *)additional_info)->ring_size;
1360         struct netvsc_device *net_device;
1361         struct net_device *ndev = hv_get_drvdata(device);
1362         struct net_device_context *net_device_ctx = netdev_priv(ndev);
1363
1364         net_device = alloc_net_device();
1365         if (!net_device)
1366                 return -ENOMEM;
1367
1368         net_device->ring_size = ring_size;
1369
1370         set_per_channel_state(device->channel, net_device->cb_buffer);
1371
1372         /* Open the channel */
1373         ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
1374                          ring_size * PAGE_SIZE, NULL, 0,
1375                          netvsc_channel_cb, device->channel);
1376
1377         if (ret != 0) {
1378                 netdev_err(ndev, "unable to open channel: %d\n", ret);
1379                 goto cleanup;
1380         }
1381
1382         /* Channel is opened */
1383         pr_info("hv_netvsc channel opened successfully\n");
1384
1385         /* If we're reopening the device we may have multiple queues, fill the
1386          * chn_table with the default channel to use it before subchannels are
1387          * opened.
1388          */
1389         for (i = 0; i < VRSS_CHANNEL_MAX; i++)
1390                 net_device->chn_table[i] = device->channel;
1391
1392         /* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
1393          * populated.
1394          */
1395         wmb();
1396
1397         net_device_ctx->nvdev = net_device;
1398
1399         /* Connect with the NetVsp */
1400         ret = netvsc_connect_vsp(device);
1401         if (ret != 0) {
1402                 netdev_err(ndev,
1403                         "unable to connect to NetVSP - %d\n", ret);
1404                 goto close;
1405         }
1406
1407         return ret;
1408
1409 close:
1410         /* Now, we can close the channel safely */
1411         vmbus_close(device->channel);
1412
1413 cleanup:
1414         free_netvsc_device(net_device);
1415
1416         return ret;
1417 }