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 /* Globals */
  36 static const char *driver_name = "netvsc";
  37
  38 /* {F8615163-DF3E-46c5-913F-F2D2F965ED0E} */
  39 static const uuid_le netvsc_device_type = {
  40         .b = {
  41                 0x63, 0x51, 0x61, 0xF8, 0x3E, 0xDF, 0xc5, 0x46,
  42                 0x91, 0x3F, 0xF2, 0xD2, 0xF9, 0x65, 0xED, 0x0E
  43         }
  44 };
  45
  46
  47 static struct netvsc_device *alloc_net_device(struct hv_device *device)
  48 {
  49         struct netvsc_device *net_device;
  50
  51         net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
  52         if (!net_device)
  53                 return NULL;
  54
  55         /* Set to 2 to allow both inbound and outbound traffic */
  56         atomic_cmpxchg(&net_device->refcnt, 0, 2);
  57
  58         net_device->dev = device;
  59         device->ext = net_device;
  60
  61         return net_device;
  62 }
  63
  64 static void free_net_device(struct netvsc_device *device)
  65 {
  66         WARN_ON(atomic_read(&device->refcnt) != 0);
  67         device->dev->ext = NULL;
  68         kfree(device);
  69 }
  70
  71
  72 /* Get the net device object iff exists and its refcount > 1 */
  73 static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
  74 {
  75         struct netvsc_device *net_device;
  76
  77         net_device = device->ext;
  78         if (net_device && atomic_read(&net_device->refcnt) > 1)
  79                 atomic_inc(&net_device->refcnt);
  80         else
  81                 net_device = NULL;
  82
  83         return net_device;
  84 }
  85
  86 /* Get the net device object iff exists and its refcount > 0 */
  87 static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
  88 {
  89         struct netvsc_device *net_device;
  90
  91         net_device = device->ext;
  92         if (net_device && atomic_read(&net_device->refcnt))
  93                 atomic_inc(&net_device->refcnt);
  94         else
  95                 net_device = NULL;
  96
  97         return net_device;
  98 }
  99
 100 static void put_net_device(struct hv_device *device)
 101 {
 102         struct netvsc_device *net_device;
 103
 104         net_device = device->ext;
 105
 106         atomic_dec(&net_device->refcnt);
 107 }
 108
 109 static struct netvsc_device *release_outbound_net_device(
 110                 struct hv_device *device)
 111 {
 112         struct netvsc_device *net_device;
 113
 114         net_device = device->ext;
 115         if (net_device == NULL)
 116                 return NULL;
 117
 118         /* Busy wait until the ref drop to 2, then set it to 1 */
 119         while (atomic_cmpxchg(&net_device->refcnt, 2, 1) != 2)
 120                 udelay(100);
 121
 122         return net_device;
 123 }
 124
 125 static struct netvsc_device *release_inbound_net_device(
 126                 struct hv_device *device)
 127 {
 128         struct netvsc_device *net_device;
 129
 130         net_device = device->ext;
 131         if (net_device == NULL)
 132                 return NULL;
 133
 134         /* Busy wait until the ref drop to 1, then set it to 0 */
 135         while (atomic_cmpxchg(&net_device->refcnt, 1, 0) != 1)
 136                 udelay(100);
 137
 138         device->ext = NULL;
 139         return net_device;
 140 }
 141
 142 static int netvsc_destroy_recv_buf(struct netvsc_device *net_device)
 143 {
 144         struct nvsp_message *revoke_packet;
 145         int ret = 0;
 146
 147         /*
 148          * If we got a section count, it means we received a
 149          * SendReceiveBufferComplete msg (ie sent
 150          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 151          * to send a revoke msg here
 152          */
 153         if (net_device->recv_section_cnt) {
 154                 /* Send the revoke receive buffer */
 155                 revoke_packet = &net_device->revoke_packet;
 156                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 157
 158                 revoke_packet->hdr.msg_type =
 159                         NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
 160                 revoke_packet->msg.v1_msg.
 161                 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 162
 163                 ret = vmbus_sendpacket(net_device->dev->channel,
 164                                        revoke_packet,
 165                                        sizeof(struct nvsp_message),
 166                                        (unsigned long)revoke_packet,
 167                                        VM_PKT_DATA_INBAND, 0);
 168                 /*
 169                  * If we failed here, we might as well return and
 170                  * have a leak rather than continue and a bugchk
 171                  */
 172                 if (ret != 0) {
 173                         dev_err(&net_device->dev->device, "unable to send "
 174                                 "revoke receive buffer to netvsp");
 175                         return -1;
 176                 }
 177         }
 178
 179         /* Teardown the gpadl on the vsp end */
 180         if (net_device->recv_buf_gpadl_handle) {
 181                 ret = vmbus_teardown_gpadl(net_device->dev->channel,
 182                            net_device->recv_buf_gpadl_handle);
 183
 184                 /* If we failed here, we might as well return and have a leak
 185                  * rather than continue and a bugchk
 186                  */
 187                 if (ret != 0) {
 188                         dev_err(&net_device->dev->device,
 189                                    "unable to teardown receive buffer's gpadl");
 190                         return -1;
 191                 }
 192                 net_device->recv_buf_gpadl_handle = 0;
 193         }
 194
 195         if (net_device->recv_buf) {
 196                 /* Free up the receive buffer */
 197                 free_pages((unsigned long)net_device->recv_buf,
 198                         get_order(net_device->recv_buf_size));
 199                 net_device->recv_buf = NULL;
 200         }
 201
 202         if (net_device->recv_section) {
 203                 net_device->recv_section_cnt = 0;
 204                 kfree(net_device->recv_section);
 205                 net_device->recv_section = NULL;
 206         }
 207
 208         return ret;
 209 }
 210
 211 static int netvsc_init_recv_buf(struct hv_device *device)
 212 {
 213         int ret = 0;
 214         int t;
 215         struct netvsc_device *net_device;
 216         struct nvsp_message *init_packet;
 217
 218         net_device = get_outbound_net_device(device);
 219         if (!net_device) {
 220                 dev_err(&device->device, "unable to get net device..."
 221                            "device being destroyed?");
 222                 return -1;
 223         }
 224
 225         net_device->recv_buf =
 226                 (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
 227                                 get_order(net_device->recv_buf_size));
 228         if (!net_device->recv_buf) {
 229                 dev_err(&device->device, "unable to allocate receive "
 230                         "buffer of size %d", net_device->recv_buf_size);
 231                 ret = -1;
 232                 goto cleanup;
 233         }
 234
 235         /*
 236          * Establish the gpadl handle for this buffer on this
 237          * channel.  Note: This call uses the vmbus connection rather
 238          * than the channel to establish the gpadl handle.
 239          */
 240         ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
 241                                     net_device->recv_buf_size,
 242                                     &net_device->recv_buf_gpadl_handle);
 243         if (ret != 0) {
 244                 dev_err(&device->device,
 245                         "unable to establish receive buffer's gpadl");
 246                 goto cleanup;
 247         }
 248
 249
 250         /* Notify the NetVsp of the gpadl handle */
 251         init_packet = &net_device->channel_init_pkt;
 252
 253         memset(init_packet, 0, sizeof(struct nvsp_message));
 254
 255         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 256         init_packet->msg.v1_msg.send_recv_buf.
 257                 gpadl_handle = net_device->recv_buf_gpadl_handle;
 258         init_packet->msg.v1_msg.
 259                 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 260
 261         /* Send the gpadl notification request */
 262         ret = vmbus_sendpacket(device->channel, init_packet,
 263                                sizeof(struct nvsp_message),
 264                                (unsigned long)init_packet,
 265                                VM_PKT_DATA_INBAND,
 266                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 267         if (ret != 0) {
 268                 dev_err(&device->device,
 269                         "unable to send receive buffer's gpadl to netvsp");
 270                 goto cleanup;
 271         }
 272
 273         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 274         BUG_ON(t == 0);
 275
 276
 277         /* Check the response */
 278         if (init_packet->msg.v1_msg.
 279             send_recv_buf_complete.status != NVSP_STAT_SUCCESS) {
 280                 dev_err(&device->device, "Unable to complete receive buffer "
 281                            "initialzation with NetVsp - status %d",
 282                            init_packet->msg.v1_msg.
 283                            send_recv_buf_complete.status);
 284                 ret = -1;
 285                 goto cleanup;
 286         }
 287
 288         /* Parse the response */
 289
 290         net_device->recv_section_cnt = init_packet->msg.
 291                 v1_msg.send_recv_buf_complete.num_sections;
 292
 293         net_device->recv_section = kmalloc(net_device->recv_section_cnt
 294                 * sizeof(struct nvsp_1_receive_buffer_section), GFP_KERNEL);
 295         if (net_device->recv_section == NULL) {
 296                 ret = -1;
 297                 goto cleanup;
 298         }
 299
 300         memcpy(net_device->recv_section,
 301                 init_packet->msg.v1_msg.
 302                send_recv_buf_complete.sections,
 303                 net_device->recv_section_cnt *
 304                sizeof(struct nvsp_1_receive_buffer_section));
 305
 306         /*
 307          * For 1st release, there should only be 1 section that represents the
 308          * entire receive buffer
 309          */
 310         if (net_device->recv_section_cnt != 1 ||
 311             net_device->recv_section->offset != 0) {
 312                 ret = -1;
 313                 goto cleanup;
 314         }
 315
 316         goto exit;
 317
 318 cleanup:
 319         netvsc_destroy_recv_buf(net_device);
 320
 321 exit:
 322         put_net_device(device);
 323         return ret;
 324 }
 325
 326
 327 static int netvsc_connect_vsp(struct hv_device *device)
 328 {
 329         int ret, t;
 330         struct netvsc_device *net_device;
 331         struct nvsp_message *init_packet;
 332         int ndis_version;
 333
 334         net_device = get_outbound_net_device(device);
 335         if (!net_device) {
 336                 dev_err(&device->device, "unable to get net device..."
 337                            "device being destroyed?");
 338                 return -1;
 339         }
 340
 341         init_packet = &net_device->channel_init_pkt;
 342
 343         memset(init_packet, 0, sizeof(struct nvsp_message));
 344         init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
 345         init_packet->msg.init_msg.init.min_protocol_ver =
 346                 NVSP_MIN_PROTOCOL_VERSION;
 347         init_packet->msg.init_msg.init.max_protocol_ver =
 348                 NVSP_MAX_PROTOCOL_VERSION;
 349
 350         /* Send the init request */
 351         ret = vmbus_sendpacket(device->channel, init_packet,
 352                                sizeof(struct nvsp_message),
 353                                (unsigned long)init_packet,
 354                                VM_PKT_DATA_INBAND,
 355                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 356
 357         if (ret != 0)
 358                 goto cleanup;
 359
 360         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 361
 362         if (t == 0) {
 363                 ret = -ETIMEDOUT;
 364                 goto cleanup;
 365         }
 366
 367         if (init_packet->msg.init_msg.init_complete.status !=
 368             NVSP_STAT_SUCCESS) {
 369                 ret = -1;
 370                 goto cleanup;
 371         }
 372
 373         if (init_packet->msg.init_msg.init_complete.
 374             negotiated_protocol_ver != NVSP_PROTOCOL_VERSION_1) {
 375                 ret = -1;
 376                 goto cleanup;
 377         }
 378         /* Send the ndis version */
 379         memset(init_packet, 0, sizeof(struct nvsp_message));
 380
 381         ndis_version = 0x00050000;
 382
 383         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
 384         init_packet->msg.v1_msg.
 385                 send_ndis_ver.ndis_major_ver =
 386                                 (ndis_version & 0xFFFF0000) >> 16;
 387         init_packet->msg.v1_msg.
 388                 send_ndis_ver.ndis_minor_ver =
 389                                 ndis_version & 0xFFFF;
 390
 391         /* Send the init request */
 392         ret = vmbus_sendpacket(device->channel, init_packet,
 393                                 sizeof(struct nvsp_message),
 394                                 (unsigned long)init_packet,
 395                                 VM_PKT_DATA_INBAND, 0);
 396         if (ret != 0) {
 397                 ret = -1;
 398                 goto cleanup;
 399         }
 400
 401         /* Post the big receive buffer to NetVSP */
 402         ret = netvsc_init_recv_buf(device);
 403
 404 cleanup:
 405         put_net_device(device);
 406         return ret;
 407 }
 408
 409 static void netvsc_disconnect_vsp(struct netvsc_device *net_device)
 410 {
 411         netvsc_destroy_recv_buf(net_device);
 412 }
 413
 414 /*
 415  * netvsc_device_remove - Callback when the root bus device is removed
 416  */
 417 int netvsc_device_remove(struct hv_device *device)
 418 {
 419         struct netvsc_device *net_device;
 420         struct hv_netvsc_packet *netvsc_packet, *pos;
 421
 422         /* Stop outbound traffic ie sends and receives completions */
 423         net_device = release_outbound_net_device(device);
 424         if (!net_device) {
 425                 dev_err(&device->device, "No net device present!!");
 426                 return -1;
 427         }
 428
 429         /* Wait for all send completions */
 430         while (atomic_read(&net_device->num_outstanding_sends)) {
 431                 dev_err(&device->device,
 432                         "waiting for %d requests to complete...",
 433                         atomic_read(&net_device->num_outstanding_sends));
 434                 udelay(100);
 435         }
 436
 437         netvsc_disconnect_vsp(net_device);
 438
 439         /* Stop inbound traffic ie receives and sends completions */
 440         net_device = release_inbound_net_device(device);
 441
 442         /* At this point, no one should be accessing netDevice except in here */
 443         dev_notice(&device->device, "net device safe to remove");
 444
 445         /* Now, we can close the channel safely */
 446         vmbus_close(device->channel);
 447
 448         /* Release all resources */
 449         list_for_each_entry_safe(netvsc_packet, pos,
 450                                  &net_device->recv_pkt_list, list_ent) {
 451                 list_del(&netvsc_packet->list_ent);
 452                 kfree(netvsc_packet);
 453         }
 454
 455         free_net_device(net_device);
 456         return 0;
 457 }
 458
 459 static void netvsc_send_completion(struct hv_device *device,
 460                                    struct vmpacket_descriptor *packet)
 461 {
 462         struct netvsc_device *net_device;
 463         struct nvsp_message *nvsp_packet;
 464         struct hv_netvsc_packet *nvsc_packet;
 465
 466         net_device = get_inbound_net_device(device);
 467         if (!net_device) {
 468                 dev_err(&device->device, "unable to get net device..."
 469                            "device being destroyed?");
 470                 return;
 471         }
 472
 473         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 474                         (packet->offset8 << 3));
 475
 476         if ((nvsp_packet->hdr.msg_type == NVSP_MSG_TYPE_INIT_COMPLETE) ||
 477             (nvsp_packet->hdr.msg_type ==
 478              NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE) ||
 479             (nvsp_packet->hdr.msg_type ==
 480              NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE)) {
 481                 /* Copy the response back */
 482                 memcpy(&net_device->channel_init_pkt, nvsp_packet,
 483                        sizeof(struct nvsp_message));
 484                 complete(&net_device->channel_init_wait);
 485         } else if (nvsp_packet->hdr.msg_type ==
 486                    NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE) {
 487                 /* Get the send context */
 488                 nvsc_packet = (struct hv_netvsc_packet *)(unsigned long)
 489                         packet->trans_id;
 490
 491                 /* Notify the layer above us */
 492                 nvsc_packet->completion.send.send_completion(
 493                         nvsc_packet->completion.send.send_completion_ctx);
 494
 495                 atomic_dec(&net_device->num_outstanding_sends);
 496         } else {
 497                 dev_err(&device->device, "Unknown send completion packet type- "
 498                            "%d received!!", nvsp_packet->hdr.msg_type);
 499         }
 500
 501         put_net_device(device);
 502 }
 503
 504 int netvsc_send(struct hv_device *device,
 505                         struct hv_netvsc_packet *packet)
 506 {
 507         struct netvsc_device *net_device;
 508         int ret = 0;
 509
 510         struct nvsp_message sendMessage;
 511
 512         net_device = get_outbound_net_device(device);
 513         if (!net_device) {
 514                 dev_err(&device->device, "net device (%p) shutting down..."
 515                            "ignoring outbound packets", net_device);
 516                 return -2;
 517         }
 518
 519         sendMessage.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 520         if (packet->is_data_pkt) {
 521                 /* 0 is RMC_DATA; */
 522                 sendMessage.msg.v1_msg.send_rndis_pkt.channel_type = 0;
 523         } else {
 524                 /* 1 is RMC_CONTROL; */
 525                 sendMessage.msg.v1_msg.send_rndis_pkt.channel_type = 1;
 526         }
 527
 528         /* Not using send buffer section */
 529         sendMessage.msg.v1_msg.send_rndis_pkt.send_buf_section_index =
 530                 0xFFFFFFFF;
 531         sendMessage.msg.v1_msg.send_rndis_pkt.send_buf_section_size = 0;
 532
 533         if (packet->page_buf_cnt) {
 534                 ret = vmbus_sendpacket_pagebuffer(device->channel,
 535                                                   packet->page_buf,
 536                                                   packet->page_buf_cnt,
 537                                                   &sendMessage,
 538                                                   sizeof(struct nvsp_message),
 539                                                   (unsigned long)packet);
 540         } else {
 541                 ret = vmbus_sendpacket(device->channel, &sendMessage,
 542                                 sizeof(struct nvsp_message),
 543                                 (unsigned long)packet,
 544                                 VM_PKT_DATA_INBAND,
 545                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 546
 547         }
 548
 549         if (ret != 0)
 550                 dev_err(&device->device, "Unable to send packet %p ret %d",
 551                            packet, ret);
 552
 553         atomic_inc(&net_device->num_outstanding_sends);
 554         put_net_device(device);
 555         return ret;
 556 }
 557
 558 static void netvsc_send_recv_completion(struct hv_device *device,
 559                                         u64 transaction_id)
 560 {
 561         struct nvsp_message recvcompMessage;
 562         int retries = 0;
 563         int ret;
 564
 565         recvcompMessage.hdr.msg_type =
 566                                 NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE;
 567
 568         /* FIXME: Pass in the status */
 569         recvcompMessage.msg.v1_msg.send_rndis_pkt_complete.status =
 570                 NVSP_STAT_SUCCESS;
 571
 572 retry_send_cmplt:
 573         /* Send the completion */
 574         ret = vmbus_sendpacket(device->channel, &recvcompMessage,
 575                                sizeof(struct nvsp_message), transaction_id,
 576                                VM_PKT_COMP, 0);
 577         if (ret == 0) {
 578                 /* success */
 579                 /* no-op */
 580         } else if (ret == -1) {
 581                 /* no more room...wait a bit and attempt to retry 3 times */
 582                 retries++;
 583                 dev_err(&device->device, "unable to send receive completion pkt"
 584                         " (tid %llx)...retrying %d", transaction_id, retries);
 585
 586                 if (retries < 4) {
 587                         udelay(100);
 588                         goto retry_send_cmplt;
 589                 } else {
 590                         dev_err(&device->device, "unable to send receive "
 591                                 "completion pkt (tid %llx)...give up retrying",
 592                                 transaction_id);
 593                 }
 594         } else {
 595                 dev_err(&device->device, "unable to send receive "
 596                         "completion pkt - %llx", transaction_id);
 597         }
 598 }
 599
 600 /* Send a receive completion packet to RNDIS device (ie NetVsp) */
 601 static void netvsc_receive_completion(void *context)
 602 {
 603         struct hv_netvsc_packet *packet = context;
 604         struct hv_device *device = (struct hv_device *)packet->device;
 605         struct netvsc_device *net_device;
 606         u64 transaction_id = 0;
 607         bool fsend_receive_comp = false;
 608         unsigned long flags;
 609
 610         /*
 611          * Even though it seems logical to do a GetOutboundNetDevice() here to
 612          * send out receive completion, we are using GetInboundNetDevice()
 613          * since we may have disable outbound traffic already.
 614          */
 615         net_device = get_inbound_net_device(device);
 616         if (!net_device) {
 617                 dev_err(&device->device, "unable to get net device..."
 618                            "device being destroyed?");
 619                 return;
 620         }
 621
 622         /* Overloading use of the lock. */
 623         spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 624
 625         packet->xfer_page_pkt->count--;
 626
 627         /*
 628          * Last one in the line that represent 1 xfer page packet.
 629          * Return the xfer page packet itself to the freelist
 630          */
 631         if (packet->xfer_page_pkt->count == 0) {
 632                 fsend_receive_comp = true;
 633                 transaction_id = packet->completion.recv.recv_completion_tid;
 634                 list_add_tail(&packet->xfer_page_pkt->list_ent,
 635                               &net_device->recv_pkt_list);
 636
 637         }
 638
 639         /* Put the packet back */
 640         list_add_tail(&packet->list_ent, &net_device->recv_pkt_list);
 641         spin_unlock_irqrestore(&net_device->recv_pkt_list_lock, flags);
 642
 643         /* Send a receive completion for the xfer page packet */
 644         if (fsend_receive_comp)
 645                 netvsc_send_recv_completion(device, transaction_id);
 646
 647         put_net_device(device);
 648 }
 649
 650 static void netvsc_receive(struct hv_device *device,
 651                             struct vmpacket_descriptor *packet)
 652 {
 653         struct netvsc_device *net_device;
 654         struct vmtransfer_page_packet_header *vmxferpage_packet;
 655         struct nvsp_message *nvsp_packet;
 656         struct hv_netvsc_packet *netvsc_packet = NULL;
 657         unsigned long start;
 658         unsigned long end, end_virtual;
 659         /* struct netvsc_driver *netvscDriver; */
 660         struct xferpage_packet *xferpage_packet = NULL;
 661         int i, j;
 662         int count = 0, bytes_remain = 0;
 663         unsigned long flags;
 664
 665         LIST_HEAD(listHead);
 666
 667         net_device = get_inbound_net_device(device);
 668         if (!net_device) {
 669                 dev_err(&device->device, "unable to get net device..."
 670                            "device being destroyed?");
 671                 return;
 672         }
 673
 674         /*
 675          * All inbound packets other than send completion should be xfer page
 676          * packet
 677          */
 678         if (packet->type != VM_PKT_DATA_USING_XFER_PAGES) {
 679                 dev_err(&device->device, "Unknown packet type received - %d",
 680                            packet->type);
 681                 put_net_device(device);
 682                 return;
 683         }
 684
 685         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 686                         (packet->offset8 << 3));
 687
 688         /* Make sure this is a valid nvsp packet */
 689         if (nvsp_packet->hdr.msg_type !=
 690             NVSP_MSG1_TYPE_SEND_RNDIS_PKT) {
 691                 dev_err(&device->device, "Unknown nvsp packet type received-"
 692                         " %d", nvsp_packet->hdr.msg_type);
 693                 put_net_device(device);
 694                 return;
 695         }
 696
 697         vmxferpage_packet = (struct vmtransfer_page_packet_header *)packet;
 698
 699         if (vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID) {
 700                 dev_err(&device->device, "Invalid xfer page set id - "
 701                            "expecting %x got %x", NETVSC_RECEIVE_BUFFER_ID,
 702                            vmxferpage_packet->xfer_pageset_id);
 703                 put_net_device(device);
 704                 return;
 705         }
 706
 707         /*
 708          * Grab free packets (range count + 1) to represent this xfer
 709          * page packet. +1 to represent the xfer page packet itself.
 710          * We grab it here so that we know exactly how many we can
 711          * fulfil
 712          */
 713         spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 714         while (!list_empty(&net_device->recv_pkt_list)) {
 715                 list_move_tail(net_device->recv_pkt_list.next, &listHead);
 716                 if (++count == vmxferpage_packet->range_cnt + 1)
 717                         break;
 718         }
 719         spin_unlock_irqrestore(&net_device->recv_pkt_list_lock, flags);
 720
 721         /*
 722          * We need at least 2 netvsc pkts (1 to represent the xfer
 723          * page and at least 1 for the range) i.e. we can handled
 724          * some of the xfer page packet ranges...
 725          */
 726         if (count < 2) {
 727                 dev_err(&device->device, "Got only %d netvsc pkt...needed "
 728                         "%d pkts. Dropping this xfer page packet completely!",
 729                         count, vmxferpage_packet->range_cnt + 1);
 730
 731                 /* Return it to the freelist */
 732                 spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
 733                 for (i = count; i != 0; i--) {
 734                         list_move_tail(listHead.next,
 735                                        &net_device->recv_pkt_list);
 736                 }
 737                 spin_unlock_irqrestore(&net_device->recv_pkt_list_lock,
 738                                        flags);
 739
 740                 netvsc_send_recv_completion(device,
 741                                             vmxferpage_packet->d.trans_id);
 742
 743                 put_net_device(device);
 744                 return;
 745         }
 746
 747         /* Remove the 1st packet to represent the xfer page packet itself */
 748         xferpage_packet = (struct xferpage_packet *)listHead.next;
 749         list_del(&xferpage_packet->list_ent);
 750
 751         /* This is how much we can satisfy */
 752         xferpage_packet->count = count - 1;
 753
 754         if (xferpage_packet->count != vmxferpage_packet->range_cnt) {
 755                 dev_err(&device->device, "Needed %d netvsc pkts to satisy "
 756                         "this xfer page...got %d",
 757                         vmxferpage_packet->range_cnt, xferpage_packet->count);
 758         }
 759
 760         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
 761         for (i = 0; i < (count - 1); i++) {
 762                 netvsc_packet = (struct hv_netvsc_packet *)listHead.next;
 763                 list_del(&netvsc_packet->list_ent);
 764
 765                 /* Initialize the netvsc packet */
 766                 netvsc_packet->xfer_page_pkt = xferpage_packet;
 767                 netvsc_packet->completion.recv.recv_completion =
 768                                         netvsc_receive_completion;
 769                 netvsc_packet->completion.recv.recv_completion_ctx =
 770                                         netvsc_packet;
 771                 netvsc_packet->device = device;
 772                 /* Save this so that we can send it back */
 773                 netvsc_packet->completion.recv.recv_completion_tid =
 774                                         vmxferpage_packet->d.trans_id;
 775
 776                 netvsc_packet->total_data_buflen =
 777                                         vmxferpage_packet->ranges[i].byte_count;
 778                 netvsc_packet->page_buf_cnt = 1;
 779
 780                 netvsc_packet->page_buf[0].len =
 781                                         vmxferpage_packet->ranges[i].byte_count;
 782
 783                 start = virt_to_phys((void *)((unsigned long)net_device->
 784                 recv_buf + vmxferpage_packet->ranges[i].byte_offset));
 785
 786                 netvsc_packet->page_buf[0].pfn = start >> PAGE_SHIFT;
 787                 end_virtual = (unsigned long)net_device->recv_buf
 788                     + vmxferpage_packet->ranges[i].byte_offset
 789                     + vmxferpage_packet->ranges[i].byte_count - 1;
 790                 end = virt_to_phys((void *)end_virtual);
 791
 792                 /* Calculate the page relative offset */
 793                 netvsc_packet->page_buf[0].offset =
 794                         vmxferpage_packet->ranges[i].byte_offset &
 795                         (PAGE_SIZE - 1);
 796                 if ((end >> PAGE_SHIFT) != (start >> PAGE_SHIFT)) {
 797                         /* Handle frame across multiple pages: */
 798                         netvsc_packet->page_buf[0].len =
 799                                 (netvsc_packet->page_buf[0].pfn <<
 800                                  PAGE_SHIFT)
 801                                 + PAGE_SIZE - start;
 802                         bytes_remain = netvsc_packet->total_data_buflen -
 803                                         netvsc_packet->page_buf[0].len;
 804                         for (j = 1; j < NETVSC_PACKET_MAXPAGE; j++) {
 805                                 netvsc_packet->page_buf[j].offset = 0;
 806                                 if (bytes_remain <= PAGE_SIZE) {
 807                                         netvsc_packet->page_buf[j].len =
 808                                                 bytes_remain;
 809                                         bytes_remain = 0;
 810                                 } else {
 811                                         netvsc_packet->page_buf[j].len =
 812                                                 PAGE_SIZE;
 813                                         bytes_remain -= PAGE_SIZE;
 814                                 }
 815                                 netvsc_packet->page_buf[j].pfn =
 816                                     virt_to_phys((void *)(end_virtual -
 817                                                 bytes_remain)) >> PAGE_SHIFT;
 818                                 netvsc_packet->page_buf_cnt++;
 819                                 if (bytes_remain == 0)
 820                                         break;
 821                         }
 822                 }
 823
 824                 /* Pass it to the upper layer */
 825                 rndis_filter_receive(device, netvsc_packet);
 826
 827                 netvsc_receive_completion(netvsc_packet->
 828                                 completion.recv.recv_completion_ctx);
 829         }
 830
 831         put_net_device(device);
 832 }
 833
 834 static void netvsc_channel_cb(void *context)
 835 {
 836         int ret;
 837         struct hv_device *device = context;
 838         struct netvsc_device *net_device;
 839         u32 bytes_recvd;
 840         u64 request_id;
 841         unsigned char *packet;
 842         struct vmpacket_descriptor *desc;
 843         unsigned char *buffer;
 844         int bufferlen = NETVSC_PACKET_SIZE;
 845
 846         packet = kzalloc(NETVSC_PACKET_SIZE * sizeof(unsigned char),
 847                          GFP_ATOMIC);
 848         if (!packet)
 849                 return;
 850         buffer = packet;
 851
 852         net_device = get_inbound_net_device(device);
 853         if (!net_device) {
 854                 dev_err(&device->device, "net device (%p) shutting down..."
 855                            "ignoring inbound packets", net_device);
 856                 goto out;
 857         }
 858
 859         do {
 860                 ret = vmbus_recvpacket_raw(device->channel, buffer, bufferlen,
 861                                            &bytes_recvd, &request_id);
 862                 if (ret == 0) {
 863                         if (bytes_recvd > 0) {
 864                                 desc = (struct vmpacket_descriptor *)buffer;
 865                                 switch (desc->type) {
 866                                 case VM_PKT_COMP:
 867                                         netvsc_send_completion(device, desc);
 868                                         break;
 869
 870                                 case VM_PKT_DATA_USING_XFER_PAGES:
 871                                         netvsc_receive(device, desc);
 872                                         break;
 873
 874                                 default:
 875                                         dev_err(&device->device,
 876                                                    "unhandled packet type %d, "
 877                                                    "tid %llx len %d\n",
 878                                                    desc->type, request_id,
 879                                                    bytes_recvd);
 880                                         break;
 881                                 }
 882
 883                                 /* reset */
 884                                 if (bufferlen > NETVSC_PACKET_SIZE) {
 885                                         kfree(buffer);
 886                                         buffer = packet;
 887                                         bufferlen = NETVSC_PACKET_SIZE;
 888                                 }
 889                         } else {
 890                                 /* reset */
 891                                 if (bufferlen > NETVSC_PACKET_SIZE) {
 892                                         kfree(buffer);
 893                                         buffer = packet;
 894                                         bufferlen = NETVSC_PACKET_SIZE;
 895                                 }
 896
 897                                 break;
 898                         }
 899                 } else if (ret == -2) {
 900                         /* Handle large packet */
 901                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
 902                         if (buffer == NULL) {
 903                                 /* Try again next time around */
 904                                 dev_err(&device->device,
 905                                            "unable to allocate buffer of size "
 906                                            "(%d)!!", bytes_recvd);
 907                                 break;
 908                         }
 909
 910                         bufferlen = bytes_recvd;
 911                 }
 912         } while (1);
 913
 914         put_net_device(device);
 915 out:
 916         kfree(buffer);
 917         return;
 918 }
 919
 920 /*
 921  * netvsc_device_add - Callback when the device belonging to this
 922  * driver is added
 923  */
 924 int netvsc_device_add(struct hv_device *device, void *additional_info)
 925 {
 926         int ret = 0;
 927         int i;
 928         int ring_size =
 929         ((struct netvsc_device_info *)additional_info)->ring_size;
 930         struct netvsc_device *net_device;
 931         struct hv_netvsc_packet *packet, *pos;
 932
 933         net_device = alloc_net_device(device);
 934         if (!net_device) {
 935                 ret = -1;
 936                 goto cleanup;
 937         }
 938
 939         /* Initialize the NetVSC channel extension */
 940         net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
 941         spin_lock_init(&net_device->recv_pkt_list_lock);
 942
 943         INIT_LIST_HEAD(&net_device->recv_pkt_list);
 944
 945         for (i = 0; i < NETVSC_RECEIVE_PACKETLIST_COUNT; i++) {
 946                 packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 947                                  (NETVSC_RECEIVE_SG_COUNT *
 948                                   sizeof(struct hv_page_buffer)), GFP_KERNEL);
 949                 if (!packet)
 950                         break;
 951
 952                 list_add_tail(&packet->list_ent,
 953                               &net_device->recv_pkt_list);
 954         }
 955         init_completion(&net_device->channel_init_wait);
 956
 957         /* Open the channel */
 958         ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
 959                          ring_size * PAGE_SIZE, NULL, 0,
 960                          netvsc_channel_cb, device);
 961
 962         if (ret != 0) {
 963                 dev_err(&device->device, "unable to open channel: %d", ret);
 964                 ret = -1;
 965                 goto cleanup;
 966         }
 967
 968         /* Channel is opened */
 969         pr_info("hv_netvsc channel opened successfully");
 970
 971         /* Connect with the NetVsp */
 972         ret = netvsc_connect_vsp(device);
 973         if (ret != 0) {
 974                 dev_err(&device->device,
 975                         "unable to connect to NetVSP - %d", ret);
 976                 ret = -1;
 977                 goto close;
 978         }
 979
 980         return ret;
 981
 982 close:
 983         /* Now, we can close the channel safely */
 984         vmbus_close(device->channel);
 985
 986 cleanup:
 987
 988         if (net_device) {
 989                 list_for_each_entry_safe(packet, pos,
 990                                          &net_device->recv_pkt_list,
 991                                          list_ent) {
 992                         list_del(&packet->list_ent);
 993                         kfree(packet);
 994                 }
 995
 996                 release_outbound_net_device(device);
 997                 release_inbound_net_device(device);
 998
 999                 free_net_device(net_device);
1000         }
1001
1002         return ret;
1003 }
1004
1005 /*
1006  * netvsc_initialize - Main entry point
1007  */
1008 int netvsc_initialize(struct hv_driver *drv)
1009 {
1010
1011         drv->name = driver_name;
1012         memcpy(&drv->dev_type, &netvsc_device_type, sizeof(uuid_le));
1013
1014         return 0;
1015 }