drivers/staging/hv/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
  31 #include "hyperv.h"
  32 #include "hyperv_net.h"
  33
  34
  35 static struct netvsc_device *alloc_net_device(struct hv_device *device)
  36 {
  37         struct netvsc_device *net_device;
  38
  39         net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
  40         if (!net_device)
  41                 return NULL;
  42
  43         /* Set to 2 to allow both inbound and outbound traffic */
  44         atomic_cmpxchg(&net_device->refcnt, 0, 2);
  45
  46         net_device->dev = device;
  47         device->ext = net_device;
  48
  49         return net_device;
  50 }
  51
  52 /* Get the net device object iff exists and its refcount > 1 */
  53 static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
  54 {
  55         struct netvsc_device *net_device;
  56
  57         net_device = device->ext;
  58         if (net_device && atomic_read(&net_device->refcnt) > 1)
  59                 atomic_inc(&net_device->refcnt);
  60         else
  61                 net_device = NULL;
  62
  63         return net_device;
  64 }
  65
  66 /* Get the net device object iff exists and its refcount > 0 */
  67 static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
  68 {
  69         struct netvsc_device *net_device;
  70
  71         net_device = device->ext;
  72         if (net_device && atomic_read(&net_device->refcnt))
  73                 atomic_inc(&net_device->refcnt);
  74         else
  75                 net_device = NULL;
  76
  77         return net_device;
  78 }
  79
  80 static void put_net_device(struct hv_device *device)
  81 {
  82         struct netvsc_device *net_device;
  83
  84         net_device = device->ext;
  85
  86         atomic_dec(&net_device->refcnt);
  87 }
  88
  89 static struct netvsc_device *release_outbound_net_device(
  90                 struct hv_device *device)
  91 {
  92         struct netvsc_device *net_device;
  93
  94         net_device = device->ext;
  95         if (net_device == NULL)
  96                 return NULL;
  97
  98         /* Busy wait until the ref drop to 2, then set it to 1 */
  99         while (atomic_cmpxchg(&net_device->refcnt, 2, 1) != 2)
 100                 udelay(100);
 101
 102         return net_device;
 103 }
 104
 105 static struct netvsc_device *release_inbound_net_device(
 106                 struct hv_device *device)
 107 {
 108         struct netvsc_device *net_device;
 109
 110         net_device = device->ext;
 111         if (net_device == NULL)
 112                 return NULL;
 113
 114         /* Busy wait until the ref drop to 1, then set it to 0 */
 115         while (atomic_cmpxchg(&net_device->refcnt, 1, 0) != 1)
 116                 udelay(100);
 117
 118         device->ext = NULL;
 119         return net_device;
 120 }
 121
 122 static int netvsc_destroy_recv_buf(struct netvsc_device *net_device)
 123 {
 124         struct nvsp_message *revoke_packet;
 125         int ret = 0;
 126
 127         /*
 128          * If we got a section count, it means we received a
 129          * SendReceiveBufferComplete msg (ie sent
 130          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 131          * to send a revoke msg here
 132          */
 133         if (net_device->recv_section_cnt) {
 134                 /* Send the revoke receive buffer */
 135                 revoke_packet = &net_device->revoke_packet;
 136                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 137
 138                 revoke_packet->hdr.msg_type =
 139                         NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
 140                 revoke_packet->msg.v1_msg.
 141                 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 142
 143                 ret = vmbus_sendpacket(net_device->dev->channel,
 144                                        revoke_packet,
 145                                        sizeof(struct nvsp_message),
 146                                        (unsigned long)revoke_packet,
 147                                        VM_PKT_DATA_INBAND, 0);
 148                 /*
 149                  * If we failed here, we might as well return and
 150                  * have a leak rather than continue and a bugchk
 151                  */
 152                 if (ret != 0) {
 153                         dev_err(&net_device->dev->device, "unable to send "
 154                                 "revoke receive buffer to netvsp");
 155                         return ret;
 156                 }
 157         }
 158
 159         /* Teardown the gpadl on the vsp end */
 160         if (net_device->recv_buf_gpadl_handle) {
 161                 ret = vmbus_teardown_gpadl(net_device->dev->channel,
 162                            net_device->recv_buf_gpadl_handle);
 163
 164                 /* If we failed here, we might as well return and have a leak
 165                  * rather than continue and a bugchk
 166                  */
 167                 if (ret != 0) {
 168                         dev_err(&net_device->dev->device,
 169                                    "unable to teardown receive buffer's gpadl");
 170                         return -ret;
 171                 }
 172                 net_device->recv_buf_gpadl_handle = 0;
 173         }
 174
 175         if (net_device->recv_buf) {
 176                 /* Free up the receive buffer */
 177                 free_pages((unsigned long)net_device->recv_buf,
 178                         get_order(net_device->recv_buf_size));
 179                 net_device->recv_buf = NULL;
 180         }
 181
 182         if (net_device->recv_section) {
 183                 net_device->recv_section_cnt = 0;
 184                 kfree(net_device->recv_section);
 185                 net_device->recv_section = NULL;
 186         }
 187
 188         return ret;
 189 }
 190
 191 static int netvsc_init_recv_buf(struct hv_device *device)
 192 {
 193         int ret = 0;
 194         int t;
 195         struct netvsc_device *net_device;
 196         struct nvsp_message *init_packet;
 197
 198         net_device = get_outbound_net_device(device);
 199         if (!net_device) {
 200                 dev_err(&device->device, "unable to get net device..."
 201                            "device being destroyed?");
 202                 return -ENODEV;
 203         }
 204
 205         net_device->recv_buf =
 206                 (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
 207                                 get_order(net_device->recv_buf_size));
 208         if (!net_device->recv_buf) {
 209                 dev_err(&device->device, "unable to allocate receive "
 210                         "buffer of size %d", net_device->recv_buf_size);
 211                 ret = -ENOMEM;
 212                 goto cleanup;
 213         }
 214
 215         /*
 216          * Establish the gpadl handle for this buffer on this
 217          * channel.  Note: This call uses the vmbus connection rather
 218          * than the channel to establish the gpadl handle.
 219          */
 220         ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
 221                                     net_device->recv_buf_size,
 222                                     &net_device->recv_buf_gpadl_handle);
 223         if (ret != 0) {
 224                 dev_err(&device->device,
 225                         "unable to establish receive buffer's gpadl");
 226                 goto cleanup;
 227         }
 228
 229
 230         /* Notify the NetVsp of the gpadl handle */
 231         init_packet = &net_device->channel_init_pkt;
 232
 233         memset(init_packet, 0, sizeof(struct nvsp_message));
 234
 235         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 236         init_packet->msg.v1_msg.send_recv_buf.
 237                 gpadl_handle = net_device->recv_buf_gpadl_handle;
 238         init_packet->msg.v1_msg.
 239                 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 240
 241         /* Send the gpadl notification request */
 242         ret = vmbus_sendpacket(device->channel, init_packet,
 243                                sizeof(struct nvsp_message),
 244                                (unsigned long)init_packet,
 245                                VM_PKT_DATA_INBAND,
 246                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 247         if (ret != 0) {
 248                 dev_err(&device->device,
 249                         "unable to send receive buffer's gpadl to netvsp");
 250                 goto cleanup;
 251         }
 252
 253         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 254         BUG_ON(t == 0);
 255
 256
 257         /* Check the response */
 258         if (init_packet->msg.v1_msg.
 259             send_recv_buf_complete.status != NVSP_STAT_SUCCESS) {
 260                 dev_err(&device->device, "Unable to complete receive buffer "
 261                            "initialzation with NetVsp - status %d",
 262                            init_packet->msg.v1_msg.
 263                            send_recv_buf_complete.status);
 264                 ret = -EINVAL;
 265                 goto cleanup;
 266         }
 267
 268         /* Parse the response */
 269
 270         net_device->recv_section_cnt = init_packet->msg.
 271                 v1_msg.send_recv_buf_complete.num_sections;
 272
 273         net_device->recv_section = kmalloc(net_device->recv_section_cnt
 274                 * sizeof(struct nvsp_1_receive_buffer_section), GFP_KERNEL);
 275         if (net_device->recv_section == NULL) {
 276                 ret = -EINVAL;
 277                 goto cleanup;
 278         }
 279
 280         memcpy(net_device->recv_section,
 281                 init_packet->msg.v1_msg.
 282                send_recv_buf_complete.sections,
 283                 net_device->recv_section_cnt *
 284                sizeof(struct nvsp_1_receive_buffer_section));
 285
 286         /*
 287          * For 1st release, there should only be 1 section that represents the
 288          * entire receive buffer
 289          */
 290         if (net_device->recv_section_cnt != 1 ||
 291             net_device->recv_section->offset != 0) {
 292                 ret = -EINVAL;
 293                 goto cleanup;
 294         }
 295
 296         goto exit;
 297
 298 cleanup:
 299         netvsc_destroy_recv_buf(net_device);
 300
 301 exit:
 302         put_net_device(device);
 303         return ret;
 304 }
 305
 306
 307 static int netvsc_connect_vsp(struct hv_device *device)
 308 {
 309         int ret, t;
 310         struct netvsc_device *net_device;
 311         struct nvsp_message *init_packet;
 312         int ndis_version;
 313
 314         net_device = get_outbound_net_device(device);
 315         if (!net_device) {
 316                 dev_err(&device->device, "unable to get net device..."
 317                            "device being destroyed?");
 318                 return -ENODEV;
 319         }
 320
 321         init_packet = &net_device->channel_init_pkt;
 322
 323         memset(init_packet, 0, sizeof(struct nvsp_message));
 324         init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
 325         init_packet->msg.init_msg.init.min_protocol_ver =
 326                 NVSP_MIN_PROTOCOL_VERSION;
 327         init_packet->msg.init_msg.init.max_protocol_ver =
 328                 NVSP_MAX_PROTOCOL_VERSION;
 329
 330         /* Send the init request */
 331         ret = vmbus_sendpacket(device->channel, init_packet,
 332                                sizeof(struct nvsp_message),
 333                                (unsigned long)init_packet,
 334                                VM_PKT_DATA_INBAND,
 335                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 336
 337         if (ret != 0)
 338                 goto cleanup;
 339
 340         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 341
 342         if (t == 0) {
 343                 ret = -ETIMEDOUT;
 344                 goto cleanup;
 345         }
 346
 347         if (init_packet->msg.init_msg.init_complete.status !=
 348             NVSP_STAT_SUCCESS) {
 349                 ret = -EINVAL;
 350                 goto cleanup;
 351         }
 352
 353         if (init_packet->msg.init_msg.init_complete.
 354             negotiated_protocol_ver != NVSP_PROTOCOL_VERSION_1) {
 355                 ret = -EPROTO;
 356                 goto cleanup;
 357         }
 358         /* Send the ndis version */
 359         memset(init_packet, 0, sizeof(struct nvsp_message));
 360
 361         ndis_version = 0x00050000;
 362
 363         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
 364         init_packet->msg.v1_msg.
 365                 send_ndis_ver.ndis_major_ver =
 366                                 (ndis_version & 0xFFFF0000) >> 16;
 367         init_packet->msg.v1_msg.
 368                 send_ndis_ver.ndis_minor_ver =
 369                                 ndis_version & 0xFFFF;
 370
 371         /* Send the init request */
 372         ret = vmbus_sendpacket(device->channel, init_packet,
 373                                 sizeof(struct nvsp_message),
 374                                 (unsigned long)init_packet,
 375                                 VM_PKT_DATA_INBAND, 0);
 376         if (ret != 0)
 377                 goto cleanup;
 378
 379         /* Post the big receive buffer to NetVSP */
 380         ret = netvsc_init_recv_buf(device);
 381
 382 cleanup:
 383         put_net_device(device);
 384         return ret;
 385 }
 386
 387 static void netvsc_disconnect_vsp(struct netvsc_device *net_device)
 388 {
 389         netvsc_destroy_recv_buf(net_device);
 390 }
 391
 392 /*
 393  * netvsc_device_remove - Callback when the root bus device is removed
 394  */
 395 int netvsc_device_remove(struct hv_device *device)
 396 {
 397         struct netvsc_device *net_device;
 398         struct hv_netvsc_packet *netvsc_packet, *pos;
 399
 400         /* Stop outbound traffic ie sends and receives completions */
 401         net_device = release_outbound_net_device(device);
 402         if (!net_device) {
 403                 dev_err(&device->device, "No net device present!!");
 404                 return -ENODEV;
 405         }
 406
 407         /* Wait for all send completions */
 408         while (atomic_read(&net_device->num_outstanding_sends)) {
 409                 dev_err(&device->device,
 410                         "waiting for %d requests to complete...",
 411                         atomic_read(&net_device->num_outstanding_sends));
 412                 udelay(100);
 413         }
 414
 415         netvsc_disconnect_vsp(net_device);
 416
 417         /* Stop inbound traffic ie receives and sends completions */
 418         net_device = release_inbound_net_device(device);
 419
 420         /* At this point, no one should be accessing netDevice except in here */
 421         dev_notice(&device->device, "net device safe to remove");
 422
 423         /* Now, we can close the channel safely */
 424         vmbus_close(device->channel);
 425
 426         /* Release all resources */
 427         list_for_each_entry_safe(netvsc_packet, pos,
 428                                  &net_device->recv_pkt_list, list_ent) {
 429                 list_del(&netvsc_packet->list_ent);
 430                 kfree(netvsc_packet);
 431         }
 432
 433         kfree(net_device);
 434         return 0;
 435 }
 436
 437 static void netvsc_send_completion(struct hv_device *device,
 438                                    struct vmpacket_descriptor *packet)
 439 {
 440         struct netvsc_device *net_device;
 441         struct nvsp_message *nvsp_packet;
 442         struct hv_netvsc_packet *nvsc_packet;
 443
 444         net_device = get_inbound_net_device(device);
 445         if (!net_device) {
 446                 dev_err(&device->device, "unable to get net device..."
 447                            "device being destroyed?");
 448                 return;
 449         }
 450
 451         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 452                         (packet->offset8 << 3));
 453
 454         if ((nvsp_packet->hdr.msg_type == NVSP_MSG_TYPE_INIT_COMPLETE) ||
 455             (nvsp_packet->hdr.msg_type ==
 456              NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE) ||
 457             (nvsp_packet->hdr.msg_type ==
 458              NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE)) {
 459                 /* Copy the response back */
 460                 memcpy(&net_device->channel_init_pkt, nvsp_packet,
 461                        sizeof(struct nvsp_message));
 462                 complete(&net_device->channel_init_wait);
 463         } else if (nvsp_packet->hdr.msg_type ==
 464                    NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE) {
 465                 /* Get the send context */
 466                 nvsc_packet = (struct hv_netvsc_packet *)(unsigned long)
 467                         packet->trans_id;
 468
 469                 /* Notify the layer above us */
 470                 nvsc_packet->completion.send.send_completion(
 471                         nvsc_packet->completion.send.send_completion_ctx);
 472
 473                 atomic_dec(&net_device->num_outstanding_sends);
 474         } else {
 475                 dev_err(&device->device, "Unknown send completion packet type- "
 476                            "%d received!!", nvsp_packet->hdr.msg_type);
 477         }
 478
 479         put_net_device(device);
 480 }
 481
 482 int netvsc_send(struct hv_device *device,
 483                         struct hv_netvsc_packet *packet)
 484 {
 485         struct netvsc_device *net_device;
 486         int ret = 0;
 487
 488         struct nvsp_message sendMessage;
 489
 490         net_device = get_outbound_net_device(device);
 491         if (!net_device) {
 492                 dev_err(&device->device, "net device (%p) shutting down..."
 493                            "ignoring outbound packets", net_device);
 494                 return -ENODEV;
 495         }
 496
 497         sendMessage.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 498         if (packet->is_data_pkt) {
 499                 /* 0 is RMC_DATA; */
 500                 sendMessage.msg.v1_msg.send_rndis_pkt.channel_type = 0;
 501         } else {
 502                 /* 1 is RMC_CONTROL; */
 503                 sendMessage.msg.v1_msg.send_rndis_pkt.channel_type = 1;
 504         }
 505
 506         /* Not using send buffer section */
 507         sendMessage.msg.v1_msg.send_rndis_pkt.send_buf_section_index =
 508                 0xFFFFFFFF;
 509         sendMessage.msg.v1_msg.send_rndis_pkt.send_buf_section_size = 0;
 510
 511         if (packet->page_buf_cnt) {
 512                 ret = vmbus_sendpacket_pagebuffer(device->channel,
 513                                                   packet->page_buf,
 514                                                   packet->page_buf_cnt,
 515                                                   &sendMessage,
 516                                                   sizeof(struct nvsp_message),
 517                                                   (unsigned long)packet);
 518         } else {
 519                 ret = vmbus_sendpacket(device->channel, &sendMessage,
 520                                 sizeof(struct nvsp_message),
 521                                 (unsigned long)packet,
 522                                 VM_PKT_DATA_INBAND,
 523                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 524
 525         }
 526
 527         if (ret != 0)
 528                 dev_err(&device->device, "Unable to send packet %p ret %d",
 529                            packet, ret);
 530
 531         atomic_inc(&net_device->num_outstanding_sends);
 532         put_net_device(device);
 533         return ret;
 534 }
 535
 536 static void netvsc_send_recv_completion(struct hv_device *device,
 537                                         u64 transaction_id)
 538 {
 539         struct nvsp_message recvcompMessage;
 540         int retries = 0;
 541         int ret;
 542
 543         recvcompMessage.hdr.msg_type =
 544                                 NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE;
 545
 546         /* FIXME: Pass in the status */
 547         recvcompMessage.msg.v1_msg.send_rndis_pkt_complete.status =
 548                 NVSP_STAT_SUCCESS;
 549
 550 retry_send_cmplt:
 551         /* Send the completion */
 552         ret = vmbus_sendpacket(device->channel, &recvcompMessage,
 553                                sizeof(struct nvsp_message), transaction_id,
 554                                VM_PKT_COMP, 0);
 555         if (ret == 0) {
 556                 /* success */
 557                 /* no-op */
 558         } else if (ret == -EAGAIN) {
 559                 /* no more room...wait a bit and attempt to retry 3 times */
 560                 retries++;
 561                 dev_err(&device->device, "unable to send receive completion pkt"
 562                         " (tid %llx)...retrying %d", transaction_id, retries);
 563
 564                 if (retries < 4) {
 565                         udelay(100);
 566                         goto retry_send_cmplt;
 567                 } else {
 568                         dev_err(&device->device, "unable to send receive "
 569                                 "completion pkt (tid %llx)...give up retrying",
 570                                 transaction_id);
 571                 }
 572         } else {
 573                 dev_err(&device->device, "unable to send receive "
 574                         "completion pkt - %llx", transaction_id);
 575         }
 576 }
 577
 578 /* Send a receive completion packet to RNDIS device (ie NetVsp) */
 579 static void netvsc_receive_completion(void *context)
 580 {
 581         struct hv_netvsc_packet *packet = context;
 582         struct hv_device *device = (struct hv_device *)packet->device;
 583         struct netvsc_device *net_device;
 584         u64 transaction_id = 0;
 585         bool fsend_receive_comp = false;
 586         unsigned long flags;
 587
 588         /*
 589          * Even though it seems logical to do a GetOutboundNetDevice() here to
 590          * send out receive completion, we are using GetInboundNetDevice()
 591          * since we may have disable outbound traffic already.
 592          */
 593         net_device = get_inbound_net_device(device);
 594         if (!net_device) {
 595                 dev_err(&device->device, "unable to get net device..."
 596                            "device being destroyed?");
 597                 return;
 598         }
 599
 600         /* Overloading use of the lock. */
 601         spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 602
 603         packet->xfer_page_pkt->count--;
 604
 605         /*
 606          * Last one in the line that represent 1 xfer page packet.
 607          * Return the xfer page packet itself to the freelist
 608          */
 609         if (packet->xfer_page_pkt->count == 0) {
 610                 fsend_receive_comp = true;
 611                 transaction_id = packet->completion.recv.recv_completion_tid;
 612                 list_add_tail(&packet->xfer_page_pkt->list_ent,
 613                               &net_device->recv_pkt_list);
 614
 615         }
 616
 617         /* Put the packet back */
 618         list_add_tail(&packet->list_ent, &net_device->recv_pkt_list);
 619         spin_unlock_irqrestore(&net_device->recv_pkt_list_lock, flags);
 620
 621         /* Send a receive completion for the xfer page packet */
 622         if (fsend_receive_comp)
 623                 netvsc_send_recv_completion(device, transaction_id);
 624
 625         put_net_device(device);
 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         unsigned long start;
 636         unsigned long end, end_virtual;
 637         /* struct netvsc_driver *netvscDriver; */
 638         struct xferpage_packet *xferpage_packet = NULL;
 639         int i, j;
 640         int count = 0, bytes_remain = 0;
 641         unsigned long flags;
 642
 643         LIST_HEAD(listHead);
 644
 645         net_device = get_inbound_net_device(device);
 646         if (!net_device) {
 647                 dev_err(&device->device, "unable to get net device..."
 648                            "device being destroyed?");
 649                 return;
 650         }
 651
 652         /*
 653          * All inbound packets other than send completion should be xfer page
 654          * packet
 655          */
 656         if (packet->type != VM_PKT_DATA_USING_XFER_PAGES) {
 657                 dev_err(&device->device, "Unknown packet type received - %d",
 658                            packet->type);
 659                 put_net_device(device);
 660                 return;
 661         }
 662
 663         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 664                         (packet->offset8 << 3));
 665
 666         /* Make sure this is a valid nvsp packet */
 667         if (nvsp_packet->hdr.msg_type !=
 668             NVSP_MSG1_TYPE_SEND_RNDIS_PKT) {
 669                 dev_err(&device->device, "Unknown nvsp packet type received-"
 670                         " %d", nvsp_packet->hdr.msg_type);
 671                 put_net_device(device);
 672                 return;
 673         }
 674
 675         vmxferpage_packet = (struct vmtransfer_page_packet_header *)packet;
 676
 677         if (vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID) {
 678                 dev_err(&device->device, "Invalid xfer page set id - "
 679                            "expecting %x got %x", NETVSC_RECEIVE_BUFFER_ID,
 680                            vmxferpage_packet->xfer_pageset_id);
 681                 put_net_device(device);
 682                 return;
 683         }
 684
 685         /*
 686          * Grab free packets (range count + 1) to represent this xfer
 687          * page packet. +1 to represent the xfer page packet itself.
 688          * We grab it here so that we know exactly how many we can
 689          * fulfil
 690          */
 691         spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 692         while (!list_empty(&net_device->recv_pkt_list)) {
 693                 list_move_tail(net_device->recv_pkt_list.next, &listHead);
 694                 if (++count == vmxferpage_packet->range_cnt + 1)
 695                         break;
 696         }
 697         spin_unlock_irqrestore(&net_device->recv_pkt_list_lock, flags);
 698
 699         /*
 700          * We need at least 2 netvsc pkts (1 to represent the xfer
 701          * page and at least 1 for the range) i.e. we can handled
 702          * some of the xfer page packet ranges...
 703          */
 704         if (count < 2) {
 705                 dev_err(&device->device, "Got only %d netvsc pkt...needed "
 706                         "%d pkts. Dropping this xfer page packet completely!",
 707                         count, vmxferpage_packet->range_cnt + 1);
 708
 709                 /* Return it to the freelist */
 710                 spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 711                 for (i = count; i != 0; i--) {
 712                         list_move_tail(listHead.next,
 713                                        &net_device->recv_pkt_list);
 714                 }
 715                 spin_unlock_irqrestore(&net_device->recv_pkt_list_lock,
 716                                        flags);
 717
 718                 netvsc_send_recv_completion(device,
 719                                             vmxferpage_packet->d.trans_id);
 720
 721                 put_net_device(device);
 722                 return;
 723         }
 724
 725         /* Remove the 1st packet to represent the xfer page packet itself */
 726         xferpage_packet = (struct xferpage_packet *)listHead.next;
 727         list_del(&xferpage_packet->list_ent);
 728
 729         /* This is how much we can satisfy */
 730         xferpage_packet->count = count - 1;
 731
 732         if (xferpage_packet->count != vmxferpage_packet->range_cnt) {
 733                 dev_err(&device->device, "Needed %d netvsc pkts to satisy "
 734                         "this xfer page...got %d",
 735                         vmxferpage_packet->range_cnt, xferpage_packet->count);
 736         }
 737
 738         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
 739         for (i = 0; i < (count - 1); i++) {
 740                 netvsc_packet = (struct hv_netvsc_packet *)listHead.next;
 741                 list_del(&netvsc_packet->list_ent);
 742
 743                 /* Initialize the netvsc packet */
 744                 netvsc_packet->xfer_page_pkt = xferpage_packet;
 745                 netvsc_packet->completion.recv.recv_completion =
 746                                         netvsc_receive_completion;
 747                 netvsc_packet->completion.recv.recv_completion_ctx =
 748                                         netvsc_packet;
 749                 netvsc_packet->device = device;
 750                 /* Save this so that we can send it back */
 751                 netvsc_packet->completion.recv.recv_completion_tid =
 752                                         vmxferpage_packet->d.trans_id;
 753
 754                 netvsc_packet->total_data_buflen =
 755                                         vmxferpage_packet->ranges[i].byte_count;
 756                 netvsc_packet->page_buf_cnt = 1;
 757
 758                 netvsc_packet->page_buf[0].len =
 759                                         vmxferpage_packet->ranges[i].byte_count;
 760
 761                 start = virt_to_phys((void *)((unsigned long)net_device->
 762                 recv_buf + vmxferpage_packet->ranges[i].byte_offset));
 763
 764                 netvsc_packet->page_buf[0].pfn = start >> PAGE_SHIFT;
 765                 end_virtual = (unsigned long)net_device->recv_buf
 766                     + vmxferpage_packet->ranges[i].byte_offset
 767                     + vmxferpage_packet->ranges[i].byte_count - 1;
 768                 end = virt_to_phys((void *)end_virtual);
 769
 770                 /* Calculate the page relative offset */
 771                 netvsc_packet->page_buf[0].offset =
 772                         vmxferpage_packet->ranges[i].byte_offset &
 773                         (PAGE_SIZE - 1);
 774                 if ((end >> PAGE_SHIFT) != (start >> PAGE_SHIFT)) {
 775                         /* Handle frame across multiple pages: */
 776                         netvsc_packet->page_buf[0].len =
 777                                 (netvsc_packet->page_buf[0].pfn <<
 778                                  PAGE_SHIFT)
 779                                 + PAGE_SIZE - start;
 780                         bytes_remain = netvsc_packet->total_data_buflen -
 781                                         netvsc_packet->page_buf[0].len;
 782                         for (j = 1; j < NETVSC_PACKET_MAXPAGE; j++) {
 783                                 netvsc_packet->page_buf[j].offset = 0;
 784                                 if (bytes_remain <= PAGE_SIZE) {
 785                                         netvsc_packet->page_buf[j].len =
 786                                                 bytes_remain;
 787                                         bytes_remain = 0;
 788                                 } else {
 789                                         netvsc_packet->page_buf[j].len =
 790                                                 PAGE_SIZE;
 791                                         bytes_remain -= PAGE_SIZE;
 792                                 }
 793                                 netvsc_packet->page_buf[j].pfn =
 794                                     virt_to_phys((void *)(end_virtual -
 795                                                 bytes_remain)) >> PAGE_SHIFT;
 796                                 netvsc_packet->page_buf_cnt++;
 797                                 if (bytes_remain == 0)
 798                                         break;
 799                         }
 800                 }
 801
 802                 /* Pass it to the upper layer */
 803                 rndis_filter_receive(device, netvsc_packet);
 804
 805                 netvsc_receive_completion(netvsc_packet->
 806                                 completion.recv.recv_completion_ctx);
 807         }
 808
 809         put_net_device(device);
 810 }
 811
 812 static void netvsc_channel_cb(void *context)
 813 {
 814         int ret;
 815         struct hv_device *device = context;
 816         struct netvsc_device *net_device;
 817         u32 bytes_recvd;
 818         u64 request_id;
 819         unsigned char *packet;
 820         struct vmpacket_descriptor *desc;
 821         unsigned char *buffer;
 822         int bufferlen = NETVSC_PACKET_SIZE;
 823
 824         packet = kzalloc(NETVSC_PACKET_SIZE * sizeof(unsigned char),
 825                          GFP_ATOMIC);
 826         if (!packet)
 827                 return;
 828         buffer = packet;
 829
 830         net_device = get_inbound_net_device(device);
 831         if (!net_device) {
 832                 dev_err(&device->device, "net device (%p) shutting down..."
 833                            "ignoring inbound packets", net_device);
 834                 goto out;
 835         }
 836
 837         do {
 838                 ret = vmbus_recvpacket_raw(device->channel, buffer, bufferlen,
 839                                            &bytes_recvd, &request_id);
 840                 if (ret == 0) {
 841                         if (bytes_recvd > 0) {
 842                                 desc = (struct vmpacket_descriptor *)buffer;
 843                                 switch (desc->type) {
 844                                 case VM_PKT_COMP:
 845                                         netvsc_send_completion(device, desc);
 846                                         break;
 847
 848                                 case VM_PKT_DATA_USING_XFER_PAGES:
 849                                         netvsc_receive(device, desc);
 850                                         break;
 851
 852                                 default:
 853                                         dev_err(&device->device,
 854                                                    "unhandled packet type %d, "
 855                                                    "tid %llx len %d\n",
 856                                                    desc->type, request_id,
 857                                                    bytes_recvd);
 858                                         break;
 859                                 }
 860
 861                                 /* reset */
 862                                 if (bufferlen > NETVSC_PACKET_SIZE) {
 863                                         kfree(buffer);
 864                                         buffer = packet;
 865                                         bufferlen = NETVSC_PACKET_SIZE;
 866                                 }
 867                         } else {
 868                                 /* reset */
 869                                 if (bufferlen > NETVSC_PACKET_SIZE) {
 870                                         kfree(buffer);
 871                                         buffer = packet;
 872                                         bufferlen = NETVSC_PACKET_SIZE;
 873                                 }
 874
 875                                 break;
 876                         }
 877                 } else if (ret == -ENOBUFS) {
 878                         /* Handle large packet */
 879                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
 880                         if (buffer == NULL) {
 881                                 /* Try again next time around */
 882                                 dev_err(&device->device,
 883                                            "unable to allocate buffer of size "
 884                                            "(%d)!!", bytes_recvd);
 885                                 break;
 886                         }
 887
 888                         bufferlen = bytes_recvd;
 889                 }
 890         } while (1);
 891
 892         put_net_device(device);
 893 out:
 894         kfree(buffer);
 895         return;
 896 }
 897
 898 /*
 899  * netvsc_device_add - Callback when the device belonging to this
 900  * driver is added
 901  */
 902 int netvsc_device_add(struct hv_device *device, void *additional_info)
 903 {
 904         int ret = 0;
 905         int i;
 906         int ring_size =
 907         ((struct netvsc_device_info *)additional_info)->ring_size;
 908         struct netvsc_device *net_device;
 909         struct hv_netvsc_packet *packet, *pos;
 910
 911         net_device = alloc_net_device(device);
 912         if (!net_device) {
 913                 ret = -ENOMEM;
 914                 goto cleanup;
 915         }
 916
 917         /* Initialize the NetVSC channel extension */
 918         net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
 919         spin_lock_init(&net_device->recv_pkt_list_lock);
 920
 921         INIT_LIST_HEAD(&net_device->recv_pkt_list);
 922
 923         for (i = 0; i < NETVSC_RECEIVE_PACKETLIST_COUNT; i++) {
 924                 packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 925                                  (NETVSC_RECEIVE_SG_COUNT *
 926                                   sizeof(struct hv_page_buffer)), GFP_KERNEL);
 927                 if (!packet)
 928                         break;
 929
 930                 list_add_tail(&packet->list_ent,
 931                               &net_device->recv_pkt_list);
 932         }
 933         init_completion(&net_device->channel_init_wait);
 934
 935         /* Open the channel */
 936         ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
 937                          ring_size * PAGE_SIZE, NULL, 0,
 938                          netvsc_channel_cb, device);
 939
 940         if (ret != 0) {
 941                 dev_err(&device->device, "unable to open channel: %d", ret);
 942                 goto cleanup;
 943         }
 944
 945         /* Channel is opened */
 946         pr_info("hv_netvsc channel opened successfully");
 947
 948         /* Connect with the NetVsp */
 949         ret = netvsc_connect_vsp(device);
 950         if (ret != 0) {
 951                 dev_err(&device->device,
 952                         "unable to connect to NetVSP - %d", ret);
 953                 goto close;
 954         }
 955
 956         return ret;
 957
 958 close:
 959         /* Now, we can close the channel safely */
 960         vmbus_close(device->channel);
 961
 962 cleanup:
 963
 964         if (net_device) {
 965                 list_for_each_entry_safe(packet, pos,
 966                                          &net_device->recv_pkt_list,
 967                                          list_ent) {
 968                         list_del(&packet->list_ent);
 969                         kfree(packet);
 970                 }
 971
 972                 release_outbound_net_device(device);
 973                 release_inbound_net_device(device);
 974
 975                 kfree(net_device);
 976         }
 977
 978         return ret;
 979 }