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, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Authors:
  18  *   Haiyang Zhang <haiyangz@microsoft.com>
  19  *   Hank Janssen  <hjanssen@microsoft.com>
  20  */
  21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  22
  23 #include <linux/kernel.h>
  24 #include <linux/sched.h>
  25 #include <linux/wait.h>
  26 #include <linux/mm.h>
  27 #include <linux/delay.h>
  28 #include <linux/io.h>
  29 #include <linux/slab.h>
  30 #include <linux/netdevice.h>
  31 #include <linux/if_ether.h>
  32
  33 #include "hyperv_net.h"
  34
  35
  36 static struct netvsc_device *alloc_net_device(struct hv_device *device)
  37 {
  38         struct netvsc_device *net_device;
  39         struct net_device *ndev = hv_get_drvdata(device);
  40
  41         net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
  42         if (!net_device)
  43                 return NULL;
  44
  45         net_device->start_remove = false;
  46         net_device->destroy = false;
  47         net_device->dev = device;
  48         net_device->ndev = ndev;
  49
  50         hv_set_drvdata(device, net_device);
  51         return net_device;
  52 }
  53
  54 static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
  55 {
  56         struct netvsc_device *net_device;
  57
  58         net_device = hv_get_drvdata(device);
  59         if (net_device && net_device->destroy)
  60                 net_device = NULL;
  61
  62         return net_device;
  63 }
  64
  65 static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
  66 {
  67         struct netvsc_device *net_device;
  68
  69         net_device = hv_get_drvdata(device);
  70
  71         if (!net_device)
  72                 goto get_in_err;
  73
  74         if (net_device->destroy &&
  75                 atomic_read(&net_device->num_outstanding_sends) == 0)
  76                 net_device = NULL;
  77
  78 get_in_err:
  79         return net_device;
  80 }
  81
  82
  83 static int netvsc_destroy_recv_buf(struct netvsc_device *net_device)
  84 {
  85         struct nvsp_message *revoke_packet;
  86         int ret = 0;
  87         struct net_device *ndev = net_device->ndev;
  88
  89         /*
  90          * If we got a section count, it means we received a
  91          * SendReceiveBufferComplete msg (ie sent
  92          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
  93          * to send a revoke msg here
  94          */
  95         if (net_device->recv_section_cnt) {
  96                 /* Send the revoke receive buffer */
  97                 revoke_packet = &net_device->revoke_packet;
  98                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
  99
 100                 revoke_packet->hdr.msg_type =
 101                         NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
 102                 revoke_packet->msg.v1_msg.
 103                 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 104
 105                 ret = vmbus_sendpacket(net_device->dev->channel,
 106                                        revoke_packet,
 107                                        sizeof(struct nvsp_message),
 108                                        (unsigned long)revoke_packet,
 109                                        VM_PKT_DATA_INBAND, 0);
 110                 /*
 111                  * If we failed here, we might as well return and
 112                  * have a leak rather than continue and a bugchk
 113                  */
 114                 if (ret != 0) {
 115                         netdev_err(ndev, "unable to send "
 116                                 "revoke receive buffer to netvsp\n");
 117                         return ret;
 118                 }
 119         }
 120
 121         /* Teardown the gpadl on the vsp end */
 122         if (net_device->recv_buf_gpadl_handle) {
 123                 ret = vmbus_teardown_gpadl(net_device->dev->channel,
 124                            net_device->recv_buf_gpadl_handle);
 125
 126                 /* If we failed here, we might as well return and have a leak
 127                  * rather than continue and a bugchk
 128                  */
 129                 if (ret != 0) {
 130                         netdev_err(ndev,
 131                                    "unable to teardown receive buffer's gpadl\n");
 132                         return ret;
 133                 }
 134                 net_device->recv_buf_gpadl_handle = 0;
 135         }
 136
 137         if (net_device->recv_buf) {
 138                 /* Free up the receive buffer */
 139                 free_pages((unsigned long)net_device->recv_buf,
 140                         get_order(net_device->recv_buf_size));
 141                 net_device->recv_buf = NULL;
 142         }
 143
 144         if (net_device->recv_section) {
 145                 net_device->recv_section_cnt = 0;
 146                 kfree(net_device->recv_section);
 147                 net_device->recv_section = NULL;
 148         }
 149
 150         return ret;
 151 }
 152
 153 static int netvsc_init_recv_buf(struct hv_device *device)
 154 {
 155         int ret = 0;
 156         int t;
 157         struct netvsc_device *net_device;
 158         struct nvsp_message *init_packet;
 159         struct net_device *ndev;
 160
 161         net_device = get_outbound_net_device(device);
 162         if (!net_device)
 163                 return -ENODEV;
 164         ndev = net_device->ndev;
 165
 166         net_device->recv_buf =
 167                 (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
 168                                 get_order(net_device->recv_buf_size));
 169         if (!net_device->recv_buf) {
 170                 netdev_err(ndev, "unable to allocate receive "
 171                         "buffer of size %d\n", net_device->recv_buf_size);
 172                 ret = -ENOMEM;
 173                 goto cleanup;
 174         }
 175
 176         /*
 177          * Establish the gpadl handle for this buffer on this
 178          * channel.  Note: This call uses the vmbus connection rather
 179          * than the channel to establish the gpadl handle.
 180          */
 181         ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
 182                                     net_device->recv_buf_size,
 183                                     &net_device->recv_buf_gpadl_handle);
 184         if (ret != 0) {
 185                 netdev_err(ndev,
 186                         "unable to establish receive buffer's gpadl\n");
 187                 goto cleanup;
 188         }
 189
 190
 191         /* Notify the NetVsp of the gpadl handle */
 192         init_packet = &net_device->channel_init_pkt;
 193
 194         memset(init_packet, 0, sizeof(struct nvsp_message));
 195
 196         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 197         init_packet->msg.v1_msg.send_recv_buf.
 198                 gpadl_handle = net_device->recv_buf_gpadl_handle;
 199         init_packet->msg.v1_msg.
 200                 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 201
 202         /* Send the gpadl notification request */
 203         ret = vmbus_sendpacket(device->channel, init_packet,
 204                                sizeof(struct nvsp_message),
 205                                (unsigned long)init_packet,
 206                                VM_PKT_DATA_INBAND,
 207                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 208         if (ret != 0) {
 209                 netdev_err(ndev,
 210                         "unable to send receive buffer's gpadl to netvsp\n");
 211                 goto cleanup;
 212         }
 213
 214         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 215         BUG_ON(t == 0);
 216
 217
 218         /* Check the response */
 219         if (init_packet->msg.v1_msg.
 220             send_recv_buf_complete.status != NVSP_STAT_SUCCESS) {
 221                 netdev_err(ndev, "Unable to complete receive buffer "
 222                            "initialization with NetVsp - status %d\n",
 223                            init_packet->msg.v1_msg.
 224                            send_recv_buf_complete.status);
 225                 ret = -EINVAL;
 226                 goto cleanup;
 227         }
 228
 229         /* Parse the response */
 230
 231         net_device->recv_section_cnt = init_packet->msg.
 232                 v1_msg.send_recv_buf_complete.num_sections;
 233
 234         net_device->recv_section = kmemdup(
 235                 init_packet->msg.v1_msg.send_recv_buf_complete.sections,
 236                 net_device->recv_section_cnt *
 237                 sizeof(struct nvsp_1_receive_buffer_section),
 238                 GFP_KERNEL);
 239         if (net_device->recv_section == NULL) {
 240                 ret = -EINVAL;
 241                 goto cleanup;
 242         }
 243
 244         /*
 245          * For 1st release, there should only be 1 section that represents the
 246          * entire receive buffer
 247          */
 248         if (net_device->recv_section_cnt != 1 ||
 249             net_device->recv_section->offset != 0) {
 250                 ret = -EINVAL;
 251                 goto cleanup;
 252         }
 253
 254         goto exit;
 255
 256 cleanup:
 257         netvsc_destroy_recv_buf(net_device);
 258
 259 exit:
 260         return ret;
 261 }
 262
 263
 264 /* Negotiate NVSP protocol version */
 265 static int negotiate_nvsp_ver(struct hv_device *device,
 266                               struct netvsc_device *net_device,
 267                               struct nvsp_message *init_packet,
 268                               u32 nvsp_ver)
 269 {
 270         int ret, t;
 271
 272         memset(init_packet, 0, sizeof(struct nvsp_message));
 273         init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
 274         init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
 275         init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
 276
 277         /* Send the init request */
 278         ret = vmbus_sendpacket(device->channel, init_packet,
 279                                sizeof(struct nvsp_message),
 280                                (unsigned long)init_packet,
 281                                VM_PKT_DATA_INBAND,
 282                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 283
 284         if (ret != 0)
 285                 return ret;
 286
 287         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 288
 289         if (t == 0)
 290                 return -ETIMEDOUT;
 291
 292         if (init_packet->msg.init_msg.init_complete.status !=
 293             NVSP_STAT_SUCCESS)
 294                 return -EINVAL;
 295
 296         if (nvsp_ver != NVSP_PROTOCOL_VERSION_2)
 297                 return 0;
 298
 299         /* NVSPv2 only: Send NDIS config */
 300         memset(init_packet, 0, sizeof(struct nvsp_message));
 301         init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
 302         init_packet->msg.v2_msg.send_ndis_config.mtu = net_device->ndev->mtu;
 303         init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
 304
 305         ret = vmbus_sendpacket(device->channel, init_packet,
 306                                 sizeof(struct nvsp_message),
 307                                 (unsigned long)init_packet,
 308                                 VM_PKT_DATA_INBAND, 0);
 309
 310         return ret;
 311 }
 312
 313 static int netvsc_connect_vsp(struct hv_device *device)
 314 {
 315         int ret;
 316         struct netvsc_device *net_device;
 317         struct nvsp_message *init_packet;
 318         int ndis_version;
 319         struct net_device *ndev;
 320
 321         net_device = get_outbound_net_device(device);
 322         if (!net_device)
 323                 return -ENODEV;
 324         ndev = net_device->ndev;
 325
 326         init_packet = &net_device->channel_init_pkt;
 327
 328         /* Negotiate the latest NVSP protocol supported */
 329         if (negotiate_nvsp_ver(device, net_device, init_packet,
 330                                NVSP_PROTOCOL_VERSION_2) == 0) {
 331                 net_device->nvsp_version = NVSP_PROTOCOL_VERSION_2;
 332         } else if (negotiate_nvsp_ver(device, net_device, init_packet,
 333                                     NVSP_PROTOCOL_VERSION_1) == 0) {
 334                 net_device->nvsp_version = NVSP_PROTOCOL_VERSION_1;
 335         } else {
 336                 ret = -EPROTO;
 337                 goto cleanup;
 338         }
 339
 340         pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
 341
 342         /* Send the ndis version */
 343         memset(init_packet, 0, sizeof(struct nvsp_message));
 344
 345         ndis_version = 0x00050001;
 346
 347         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
 348         init_packet->msg.v1_msg.
 349                 send_ndis_ver.ndis_major_ver =
 350                                 (ndis_version & 0xFFFF0000) >> 16;
 351         init_packet->msg.v1_msg.
 352                 send_ndis_ver.ndis_minor_ver =
 353                                 ndis_version & 0xFFFF;
 354
 355         /* Send the init request */
 356         ret = vmbus_sendpacket(device->channel, init_packet,
 357                                 sizeof(struct nvsp_message),
 358                                 (unsigned long)init_packet,
 359                                 VM_PKT_DATA_INBAND, 0);
 360         if (ret != 0)
 361                 goto cleanup;
 362
 363         /* Post the big receive buffer to NetVSP */
 364         ret = netvsc_init_recv_buf(device);
 365
 366 cleanup:
 367         return ret;
 368 }
 369
 370 static void netvsc_disconnect_vsp(struct netvsc_device *net_device)
 371 {
 372         netvsc_destroy_recv_buf(net_device);
 373 }
 374
 375 /*
 376  * netvsc_device_remove - Callback when the root bus device is removed
 377  */
 378 int netvsc_device_remove(struct hv_device *device)
 379 {
 380         struct netvsc_device *net_device;
 381         struct hv_netvsc_packet *netvsc_packet, *pos;
 382         unsigned long flags;
 383
 384         net_device = hv_get_drvdata(device);
 385         spin_lock_irqsave(&device->channel->inbound_lock, flags);
 386         net_device->destroy = true;
 387         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
 388
 389         /* Wait for all send completions */
 390         while (atomic_read(&net_device->num_outstanding_sends)) {
 391                 dev_info(&device->device,
 392                         "waiting for %d requests to complete...\n",
 393                         atomic_read(&net_device->num_outstanding_sends));
 394                 udelay(100);
 395         }
 396
 397         netvsc_disconnect_vsp(net_device);
 398
 399         /*
 400          * Since we have already drained, we don't need to busy wait
 401          * as was done in final_release_stor_device()
 402          * Note that we cannot set the ext pointer to NULL until
 403          * we have drained - to drain the outgoing packets, we need to
 404          * allow incoming packets.
 405          */
 406
 407         spin_lock_irqsave(&device->channel->inbound_lock, flags);
 408         hv_set_drvdata(device, NULL);
 409         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
 410
 411         /*
 412          * At this point, no one should be accessing net_device
 413          * except in here
 414          */
 415         dev_notice(&device->device, "net device safe to remove\n");
 416
 417         /* Now, we can close the channel safely */
 418         vmbus_close(device->channel);
 419
 420         /* Release all resources */
 421         list_for_each_entry_safe(netvsc_packet, pos,
 422                                  &net_device->recv_pkt_list, list_ent) {
 423                 list_del(&netvsc_packet->list_ent);
 424                 kfree(netvsc_packet);
 425         }
 426
 427         kfree(net_device);
 428         return 0;
 429 }
 430
 431 static void netvsc_send_completion(struct hv_device *device,
 432                                    struct vmpacket_descriptor *packet)
 433 {
 434         struct netvsc_device *net_device;
 435         struct nvsp_message *nvsp_packet;
 436         struct hv_netvsc_packet *nvsc_packet;
 437         struct net_device *ndev;
 438
 439         net_device = get_inbound_net_device(device);
 440         if (!net_device)
 441                 return;
 442         ndev = net_device->ndev;
 443
 444         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 445                         (packet->offset8 << 3));
 446
 447         if ((nvsp_packet->hdr.msg_type == NVSP_MSG_TYPE_INIT_COMPLETE) ||
 448             (nvsp_packet->hdr.msg_type ==
 449              NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE) ||
 450             (nvsp_packet->hdr.msg_type ==
 451              NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE)) {
 452                 /* Copy the response back */
 453                 memcpy(&net_device->channel_init_pkt, nvsp_packet,
 454                        sizeof(struct nvsp_message));
 455                 complete(&net_device->channel_init_wait);
 456         } else if (nvsp_packet->hdr.msg_type ==
 457                    NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE) {
 458                 /* Get the send context */
 459                 nvsc_packet = (struct hv_netvsc_packet *)(unsigned long)
 460                         packet->trans_id;
 461
 462                 /* Notify the layer above us */
 463                 nvsc_packet->completion.send.send_completion(
 464                         nvsc_packet->completion.send.send_completion_ctx);
 465
 466                 atomic_dec(&net_device->num_outstanding_sends);
 467
 468                 if (netif_queue_stopped(ndev) && !net_device->start_remove)
 469                         netif_wake_queue(ndev);
 470         } else {
 471                 netdev_err(ndev, "Unknown send completion packet type- "
 472                            "%d received!!\n", nvsp_packet->hdr.msg_type);
 473         }
 474
 475 }
 476
 477 int netvsc_send(struct hv_device *device,
 478                         struct hv_netvsc_packet *packet)
 479 {
 480         struct netvsc_device *net_device;
 481         int ret = 0;
 482         struct nvsp_message sendMessage;
 483         struct net_device *ndev;
 484
 485         net_device = get_outbound_net_device(device);
 486         if (!net_device)
 487                 return -ENODEV;
 488         ndev = net_device->ndev;
 489
 490         sendMessage.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 491         if (packet->is_data_pkt) {
 492                 /* 0 is RMC_DATA; */
 493                 sendMessage.msg.v1_msg.send_rndis_pkt.channel_type = 0;
 494         } else {
 495                 /* 1 is RMC_CONTROL; */
 496                 sendMessage.msg.v1_msg.send_rndis_pkt.channel_type = 1;
 497         }
 498
 499         /* Not using send buffer section */
 500         sendMessage.msg.v1_msg.send_rndis_pkt.send_buf_section_index =
 501                 0xFFFFFFFF;
 502         sendMessage.msg.v1_msg.send_rndis_pkt.send_buf_section_size = 0;
 503
 504         if (packet->page_buf_cnt) {
 505                 ret = vmbus_sendpacket_pagebuffer(device->channel,
 506                                                   packet->page_buf,
 507                                                   packet->page_buf_cnt,
 508                                                   &sendMessage,
 509                                                   sizeof(struct nvsp_message),
 510                                                   (unsigned long)packet);
 511         } else {
 512                 ret = vmbus_sendpacket(device->channel, &sendMessage,
 513                                 sizeof(struct nvsp_message),
 514                                 (unsigned long)packet,
 515                                 VM_PKT_DATA_INBAND,
 516                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 517
 518         }
 519
 520         if (ret == 0) {
 521                 atomic_inc(&net_device->num_outstanding_sends);
 522         } else if (ret == -EAGAIN) {
 523                 netif_stop_queue(ndev);
 524                 if (atomic_read(&net_device->num_outstanding_sends) < 1)
 525                         netif_wake_queue(ndev);
 526         } else {
 527                 netdev_err(ndev, "Unable to send packet %p ret %d\n",
 528                            packet, ret);
 529         }
 530
 531         return ret;
 532 }
 533
 534 static void netvsc_send_recv_completion(struct hv_device *device,
 535                                         u64 transaction_id)
 536 {
 537         struct nvsp_message recvcompMessage;
 538         int retries = 0;
 539         int ret;
 540         struct net_device *ndev;
 541         struct netvsc_device *net_device = hv_get_drvdata(device);
 542
 543         ndev = net_device->ndev;
 544
 545         recvcompMessage.hdr.msg_type =
 546                                 NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE;
 547
 548         /* FIXME: Pass in the status */
 549         recvcompMessage.msg.v1_msg.send_rndis_pkt_complete.status =
 550                 NVSP_STAT_SUCCESS;
 551
 552 retry_send_cmplt:
 553         /* Send the completion */
 554         ret = vmbus_sendpacket(device->channel, &recvcompMessage,
 555                                sizeof(struct nvsp_message), transaction_id,
 556                                VM_PKT_COMP, 0);
 557         if (ret == 0) {
 558                 /* success */
 559                 /* no-op */
 560         } else if (ret == -EAGAIN) {
 561                 /* no more room...wait a bit and attempt to retry 3 times */
 562                 retries++;
 563                 netdev_err(ndev, "unable to send receive completion pkt"
 564                         " (tid %llx)...retrying %d\n", transaction_id, retries);
 565
 566                 if (retries < 4) {
 567                         udelay(100);
 568                         goto retry_send_cmplt;
 569                 } else {
 570                         netdev_err(ndev, "unable to send receive "
 571                                 "completion pkt (tid %llx)...give up retrying\n",
 572                                 transaction_id);
 573                 }
 574         } else {
 575                 netdev_err(ndev, "unable to send receive "
 576                         "completion pkt - %llx\n", transaction_id);
 577         }
 578 }
 579
 580 /* Send a receive completion packet to RNDIS device (ie NetVsp) */
 581 static void netvsc_receive_completion(void *context)
 582 {
 583         struct hv_netvsc_packet *packet = context;
 584         struct hv_device *device = (struct hv_device *)packet->device;
 585         struct netvsc_device *net_device;
 586         u64 transaction_id = 0;
 587         bool fsend_receive_comp = false;
 588         unsigned long flags;
 589         struct net_device *ndev;
 590
 591         /*
 592          * Even though it seems logical to do a GetOutboundNetDevice() here to
 593          * send out receive completion, we are using GetInboundNetDevice()
 594          * since we may have disable outbound traffic already.
 595          */
 596         net_device = get_inbound_net_device(device);
 597         if (!net_device)
 598                 return;
 599         ndev = net_device->ndev;
 600
 601         /* Overloading use of the lock. */
 602         spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 603
 604         packet->xfer_page_pkt->count--;
 605
 606         /*
 607          * Last one in the line that represent 1 xfer page packet.
 608          * Return the xfer page packet itself to the freelist
 609          */
 610         if (packet->xfer_page_pkt->count == 0) {
 611                 fsend_receive_comp = true;
 612                 transaction_id = packet->completion.recv.recv_completion_tid;
 613                 list_add_tail(&packet->xfer_page_pkt->list_ent,
 614                               &net_device->recv_pkt_list);
 615
 616         }
 617
 618         /* Put the packet back */
 619         list_add_tail(&packet->list_ent, &net_device->recv_pkt_list);
 620         spin_unlock_irqrestore(&net_device->recv_pkt_list_lock, flags);
 621
 622         /* Send a receive completion for the xfer page packet */
 623         if (fsend_receive_comp)
 624                 netvsc_send_recv_completion(device, transaction_id);
 625
 626 }
 627
 628 static void netvsc_receive(struct hv_device *device,
 629                             struct vmpacket_descriptor *packet)
 630 {
 631         struct netvsc_device *net_device;
 632         struct vmtransfer_page_packet_header *vmxferpage_packet;
 633         struct nvsp_message *nvsp_packet;
 634         struct hv_netvsc_packet *netvsc_packet = NULL;
 635         /* struct netvsc_driver *netvscDriver; */
 636         struct xferpage_packet *xferpage_packet = NULL;
 637         int i;
 638         int count = 0;
 639         unsigned long flags;
 640         struct net_device *ndev;
 641
 642         LIST_HEAD(listHead);
 643
 644         net_device = get_inbound_net_device(device);
 645         if (!net_device)
 646                 return;
 647         ndev = net_device->ndev;
 648
 649         /*
 650          * All inbound packets other than send completion should be xfer page
 651          * packet
 652          */
 653         if (packet->type != VM_PKT_DATA_USING_XFER_PAGES) {
 654                 netdev_err(ndev, "Unknown packet type received - %d\n",
 655                            packet->type);
 656                 return;
 657         }
 658
 659         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 660                         (packet->offset8 << 3));
 661
 662         /* Make sure this is a valid nvsp packet */
 663         if (nvsp_packet->hdr.msg_type !=
 664             NVSP_MSG1_TYPE_SEND_RNDIS_PKT) {
 665                 netdev_err(ndev, "Unknown nvsp packet type received-"
 666                         " %d\n", nvsp_packet->hdr.msg_type);
 667                 return;
 668         }
 669
 670         vmxferpage_packet = (struct vmtransfer_page_packet_header *)packet;
 671
 672         if (vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID) {
 673                 netdev_err(ndev, "Invalid xfer page set id - "
 674                            "expecting %x got %x\n", NETVSC_RECEIVE_BUFFER_ID,
 675                            vmxferpage_packet->xfer_pageset_id);
 676                 return;
 677         }
 678
 679         /*
 680          * Grab free packets (range count + 1) to represent this xfer
 681          * page packet. +1 to represent the xfer page packet itself.
 682          * We grab it here so that we know exactly how many we can
 683          * fulfil
 684          */
 685         spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 686         while (!list_empty(&net_device->recv_pkt_list)) {
 687                 list_move_tail(net_device->recv_pkt_list.next, &listHead);
 688                 if (++count == vmxferpage_packet->range_cnt + 1)
 689                         break;
 690         }
 691         spin_unlock_irqrestore(&net_device->recv_pkt_list_lock, flags);
 692
 693         /*
 694          * We need at least 2 netvsc pkts (1 to represent the xfer
 695          * page and at least 1 for the range) i.e. we can handled
 696          * some of the xfer page packet ranges...
 697          */
 698         if (count < 2) {
 699                 netdev_err(ndev, "Got only %d netvsc pkt...needed "
 700                         "%d pkts. Dropping this xfer page packet completely!\n",
 701                         count, vmxferpage_packet->range_cnt + 1);
 702
 703                 /* Return it to the freelist */
 704                 spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 705                 for (i = count; i != 0; i--) {
 706                         list_move_tail(listHead.next,
 707                                        &net_device->recv_pkt_list);
 708                 }
 709                 spin_unlock_irqrestore(&net_device->recv_pkt_list_lock,
 710                                        flags);
 711
 712                 netvsc_send_recv_completion(device,
 713                                             vmxferpage_packet->d.trans_id);
 714
 715                 return;
 716         }
 717
 718         /* Remove the 1st packet to represent the xfer page packet itself */
 719         xferpage_packet = (struct xferpage_packet *)listHead.next;
 720         list_del(&xferpage_packet->list_ent);
 721
 722         /* This is how much we can satisfy */
 723         xferpage_packet->count = count - 1;
 724
 725         if (xferpage_packet->count != vmxferpage_packet->range_cnt) {
 726                 netdev_err(ndev, "Needed %d netvsc pkts to satisfy "
 727                         "this xfer page...got %d\n",
 728                         vmxferpage_packet->range_cnt, xferpage_packet->count);
 729         }
 730
 731         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
 732         for (i = 0; i < (count - 1); i++) {
 733                 netvsc_packet = (struct hv_netvsc_packet *)listHead.next;
 734                 list_del(&netvsc_packet->list_ent);
 735
 736                 /* Initialize the netvsc packet */
 737                 netvsc_packet->xfer_page_pkt = xferpage_packet;
 738                 netvsc_packet->completion.recv.recv_completion =
 739                                         netvsc_receive_completion;
 740                 netvsc_packet->completion.recv.recv_completion_ctx =
 741                                         netvsc_packet;
 742                 netvsc_packet->device = device;
 743                 /* Save this so that we can send it back */
 744                 netvsc_packet->completion.recv.recv_completion_tid =
 745                                         vmxferpage_packet->d.trans_id;
 746
 747                 netvsc_packet->data = (void *)((unsigned long)net_device->
 748                         recv_buf + vmxferpage_packet->ranges[i].byte_offset);
 749                 netvsc_packet->total_data_buflen =
 750                                         vmxferpage_packet->ranges[i].byte_count;
 751
 752                 /* Pass it to the upper layer */
 753                 rndis_filter_receive(device, netvsc_packet);
 754
 755                 netvsc_receive_completion(netvsc_packet->
 756                                 completion.recv.recv_completion_ctx);
 757         }
 758
 759 }
 760
 761 static void netvsc_channel_cb(void *context)
 762 {
 763         int ret;
 764         struct hv_device *device = context;
 765         struct netvsc_device *net_device;
 766         u32 bytes_recvd;
 767         u64 request_id;
 768         unsigned char *packet;
 769         struct vmpacket_descriptor *desc;
 770         unsigned char *buffer;
 771         int bufferlen = NETVSC_PACKET_SIZE;
 772         struct net_device *ndev;
 773
 774         packet = kzalloc(NETVSC_PACKET_SIZE * sizeof(unsigned char),
 775                          GFP_ATOMIC);
 776         if (!packet)
 777                 return;
 778         buffer = packet;
 779
 780         net_device = get_inbound_net_device(device);
 781         if (!net_device)
 782                 goto out;
 783         ndev = net_device->ndev;
 784
 785         do {
 786                 ret = vmbus_recvpacket_raw(device->channel, buffer, bufferlen,
 787                                            &bytes_recvd, &request_id);
 788                 if (ret == 0) {
 789                         if (bytes_recvd > 0) {
 790                                 desc = (struct vmpacket_descriptor *)buffer;
 791                                 switch (desc->type) {
 792                                 case VM_PKT_COMP:
 793                                         netvsc_send_completion(device, desc);
 794                                         break;
 795
 796                                 case VM_PKT_DATA_USING_XFER_PAGES:
 797                                         netvsc_receive(device, desc);
 798                                         break;
 799
 800                                 default:
 801                                         netdev_err(ndev,
 802                                                    "unhandled packet type %d, "
 803                                                    "tid %llx len %d\n",
 804                                                    desc->type, request_id,
 805                                                    bytes_recvd);
 806                                         break;
 807                                 }
 808
 809                                 /* reset */
 810                                 if (bufferlen > NETVSC_PACKET_SIZE) {
 811                                         kfree(buffer);
 812                                         buffer = packet;
 813                                         bufferlen = NETVSC_PACKET_SIZE;
 814                                 }
 815                         } else {
 816                                 /* reset */
 817                                 if (bufferlen > NETVSC_PACKET_SIZE) {
 818                                         kfree(buffer);
 819                                         buffer = packet;
 820                                         bufferlen = NETVSC_PACKET_SIZE;
 821                                 }
 822
 823                                 break;
 824                         }
 825                 } else if (ret == -ENOBUFS) {
 826                         /* Handle large packet */
 827                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
 828                         if (buffer == NULL) {
 829                                 /* Try again next time around */
 830                                 netdev_err(ndev,
 831                                            "unable to allocate buffer of size "
 832                                            "(%d)!!\n", bytes_recvd);
 833                                 break;
 834                         }
 835
 836                         bufferlen = bytes_recvd;
 837                 }
 838         } while (1);
 839
 840 out:
 841         kfree(buffer);
 842         return;
 843 }
 844
 845 /*
 846  * netvsc_device_add - Callback when the device belonging to this
 847  * driver is added
 848  */
 849 int netvsc_device_add(struct hv_device *device, void *additional_info)
 850 {
 851         int ret = 0;
 852         int i;
 853         int ring_size =
 854         ((struct netvsc_device_info *)additional_info)->ring_size;
 855         struct netvsc_device *net_device;
 856         struct hv_netvsc_packet *packet, *pos;
 857         struct net_device *ndev;
 858
 859         net_device = alloc_net_device(device);
 860         if (!net_device) {
 861                 ret = -ENOMEM;
 862                 goto cleanup;
 863         }
 864
 865         /*
 866          * Coming into this function, struct net_device * is
 867          * registered as the driver private data.
 868          * In alloc_net_device(), we register struct netvsc_device *
 869          * as the driver private data and stash away struct net_device *
 870          * in struct netvsc_device *.
 871          */
 872         ndev = net_device->ndev;
 873
 874         /* Initialize the NetVSC channel extension */
 875         net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
 876         spin_lock_init(&net_device->recv_pkt_list_lock);
 877
 878         INIT_LIST_HEAD(&net_device->recv_pkt_list);
 879
 880         for (i = 0; i < NETVSC_RECEIVE_PACKETLIST_COUNT; i++) {
 881                 packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 882                                  (NETVSC_RECEIVE_SG_COUNT *
 883                                   sizeof(struct hv_page_buffer)), GFP_KERNEL);
 884                 if (!packet)
 885                         break;
 886
 887                 list_add_tail(&packet->list_ent,
 888                               &net_device->recv_pkt_list);
 889         }
 890         init_completion(&net_device->channel_init_wait);
 891
 892         /* Open the channel */
 893         ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
 894                          ring_size * PAGE_SIZE, NULL, 0,
 895                          netvsc_channel_cb, device);
 896
 897         if (ret != 0) {
 898                 netdev_err(ndev, "unable to open channel: %d\n", ret);
 899                 goto cleanup;
 900         }
 901
 902         /* Channel is opened */
 903         pr_info("hv_netvsc channel opened successfully\n");
 904
 905         /* Connect with the NetVsp */
 906         ret = netvsc_connect_vsp(device);
 907         if (ret != 0) {
 908                 netdev_err(ndev,
 909                         "unable to connect to NetVSP - %d\n", ret);
 910                 goto close;
 911         }
 912
 913         return ret;
 914
 915 close:
 916         /* Now, we can close the channel safely */
 917         vmbus_close(device->channel);
 918
 919 cleanup:
 920
 921         if (net_device) {
 922                 list_for_each_entry_safe(packet, pos,
 923                                          &net_device->recv_pkt_list,
 924                                          list_ent) {
 925                         list_del(&packet->list_ent);
 926                         kfree(packet);
 927                 }
 928
 929                 kfree(net_device);
 930         }
 931
 932         return ret;
 933 }