drivers/staging/hv/storvsc.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 #include <linux/kernel.h>
  22 #include <linux/sched.h>
  23 #include <linux/wait.h>
  24 #include <linux/string.h>
  25 #include <linux/slab.h>
  26 #include <linux/mm.h>
  27 #include <linux/delay.h>
  28 #include "hv_api.h"
  29 #include "logging.h"
  30 #include "storvsc_api.h"
  31 #include "vmbus_packet_format.h"
  32 #include "vstorage.h"
  33 #include "channel.h"
  34
  35
  36 struct storvsc_request_extension {
  37         /* LIST_ENTRY ListEntry; */
  38
  39         struct hv_storvsc_request *request;
  40         struct hv_device *device;
  41
  42         /* Synchronize the request/response if needed */
  43         int wait_condition;
  44         wait_queue_head_t wait_event;
  45
  46         struct vstor_packet vstor_packet;
  47 };
  48
  49 /* A storvsc device is a device object that contains a vmbus channel */
  50 struct storvsc_device {
  51         struct hv_device *device;
  52
  53         /* 0 indicates the device is being destroyed */
  54         atomic_t ref_count;
  55
  56         atomic_t num_outstanding_req;
  57
  58         /*
  59          * Each unique Port/Path/Target represents 1 channel ie scsi
  60          * controller. In reality, the pathid, targetid is always 0
  61          * and the port is set by us
  62          */
  63         unsigned int port_number;
  64         unsigned char path_id;
  65         unsigned char target_id;
  66
  67         /* LIST_ENTRY OutstandingRequestList; */
  68         /* HANDLE OutstandingRequestLock; */
  69
  70         /* Used for vsc/vsp channel reset process */
  71         struct storvsc_request_extension init_request;
  72         struct storvsc_request_extension reset_request;
  73 };
  74
  75
  76 static const char *g_driver_name = "storvsc";
  77
  78 /* {ba6163d9-04a1-4d29-b605-72e2ffb1dc7f} */
  79 static const struct hv_guid gStorVscDeviceType = {
  80         .data = {
  81                 0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
  82                 0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f
  83         }
  84 };
  85
  86
  87 static inline struct storvsc_device *alloc_stor_device(struct hv_device *device)
  88 {
  89         struct storvsc_device *stor_device;
  90
  91         stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
  92         if (!stor_device)
  93                 return NULL;
  94
  95         /* Set to 2 to allow both inbound and outbound traffics */
  96         /* (ie get_stor_device() and must_get_stor_device()) to proceed. */
  97         atomic_cmpxchg(&stor_device->ref_count, 0, 2);
  98
  99         stor_device->device = device;
 100         device->ext = stor_device;
 101
 102         return stor_device;
 103 }
 104
 105 static inline void free_stor_device(struct storvsc_device *device)
 106 {
 107         /* ASSERT(atomic_read(&device->ref_count) == 0); */
 108         kfree(device);
 109 }
 110
 111 /* Get the stordevice object iff exists and its refcount > 1 */
 112 static inline struct storvsc_device *get_stor_device(struct hv_device *device)
 113 {
 114         struct storvsc_device *stor_device;
 115
 116         stor_device = (struct storvsc_device *)device->ext;
 117         if (stor_device && atomic_read(&stor_device->ref_count) > 1)
 118                 atomic_inc(&stor_device->ref_count);
 119         else
 120                 stor_device = NULL;
 121
 122         return stor_device;
 123 }
 124
 125 /* Get the stordevice object iff exists and its refcount > 0 */
 126 static inline struct storvsc_device *must_get_stor_device(
 127                                         struct hv_device *device)
 128 {
 129         struct storvsc_device *stor_device;
 130
 131         stor_device = (struct storvsc_device *)device->ext;
 132         if (stor_device && atomic_read(&stor_device->ref_count))
 133                 atomic_inc(&stor_device->ref_count);
 134         else
 135                 stor_device = NULL;
 136
 137         return stor_device;
 138 }
 139
 140 static inline void put_stor_device(struct hv_device *device)
 141 {
 142         struct storvsc_device *stor_device;
 143
 144         stor_device = (struct storvsc_device *)device->ext;
 145         /* ASSERT(stor_device); */
 146
 147         atomic_dec(&stor_device->ref_count);
 148         /* ASSERT(atomic_read(&stor_device->ref_count)); */
 149 }
 150
 151 /* Drop ref count to 1 to effectively disable get_stor_device() */
 152 static inline struct storvsc_device *release_stor_device(
 153                                         struct hv_device *device)
 154 {
 155         struct storvsc_device *stor_device;
 156
 157         stor_device = (struct storvsc_device *)device->ext;
 158         /* ASSERT(stor_device); */
 159
 160         /* Busy wait until the ref drop to 2, then set it to 1 */
 161         while (atomic_cmpxchg(&stor_device->ref_count, 2, 1) != 2)
 162                 udelay(100);
 163
 164         return stor_device;
 165 }
 166
 167 /* Drop ref count to 0. No one can use stor_device object. */
 168 static inline struct storvsc_device *final_release_stor_device(
 169                         struct hv_device *device)
 170 {
 171         struct storvsc_device *stor_device;
 172
 173         stor_device = (struct storvsc_device *)device->ext;
 174         /* ASSERT(stor_device); */
 175
 176         /* Busy wait until the ref drop to 1, then set it to 0 */
 177         while (atomic_cmpxchg(&stor_device->ref_count, 1, 0) != 1)
 178                 udelay(100);
 179
 180         device->ext = NULL;
 181         return stor_device;
 182 }
 183
 184 static int stor_vsc_channel_init(struct hv_device *device)
 185 {
 186         struct storvsc_device *stor_device;
 187         struct storvsc_request_extension *request;
 188         struct vstor_packet *vstor_packet;
 189         int ret;
 190
 191         stor_device = get_stor_device(device);
 192         if (!stor_device) {
 193                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 194                            "device being destroyed?");
 195                 return -1;
 196         }
 197
 198         request = &stor_device->init_request;
 199         vstor_packet = &request->vstor_packet;
 200
 201         /*
 202          * Now, initiate the vsc/vsp initialization protocol on the open
 203          * channel
 204          */
 205         memset(request, 0, sizeof(struct storvsc_request_extension));
 206         init_waitqueue_head(&request->wait_event);
 207         vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
 208         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 209
 210         DPRINT_INFO(STORVSC, "BEGIN_INITIALIZATION_OPERATION...");
 211
 212         request->wait_condition = 0;
 213         ret = vmbus_sendpacket(device->channel, vstor_packet,
 214                                sizeof(struct vstor_packet),
 215                                (unsigned long)request,
 216                                VM_PKT_DATA_INBAND,
 217                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 218         if (ret != 0) {
 219                 DPRINT_ERR(STORVSC,
 220                            "unable to send BEGIN_INITIALIZATION_OPERATION");
 221                 goto cleanup;
 222         }
 223
 224         wait_event_timeout(request->wait_event, request->wait_condition,
 225                         msecs_to_jiffies(1000));
 226         if (request->wait_condition == 0) {
 227                 ret = -ETIMEDOUT;
 228                 goto cleanup;
 229         }
 230
 231
 232         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 233             vstor_packet->status != 0) {
 234                 DPRINT_ERR(STORVSC, "BEGIN_INITIALIZATION_OPERATION failed "
 235                            "(op %d status 0x%x)",
 236                            vstor_packet->operation, vstor_packet->status);
 237                 goto cleanup;
 238         }
 239
 240         DPRINT_INFO(STORVSC, "QUERY_PROTOCOL_VERSION_OPERATION...");
 241
 242         /* reuse the packet for version range supported */
 243         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 244         vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
 245         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 246
 247         vstor_packet->version.major_minor = VMSTOR_PROTOCOL_VERSION_CURRENT;
 248         FILL_VMSTOR_REVISION(vstor_packet->version.revision);
 249
 250         request->wait_condition = 0;
 251         ret = vmbus_sendpacket(device->channel, vstor_packet,
 252                                sizeof(struct vstor_packet),
 253                                (unsigned long)request,
 254                                VM_PKT_DATA_INBAND,
 255                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 256         if (ret != 0) {
 257                 DPRINT_ERR(STORVSC,
 258                            "unable to send BEGIN_INITIALIZATION_OPERATION");
 259                 goto cleanup;
 260         }
 261
 262         wait_event_timeout(request->wait_event, request->wait_condition,
 263                         msecs_to_jiffies(1000));
 264         if (request->wait_condition == 0) {
 265                 ret = -ETIMEDOUT;
 266                 goto cleanup;
 267         }
 268
 269         /* TODO: Check returned version */
 270         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 271             vstor_packet->status != 0) {
 272                 DPRINT_ERR(STORVSC, "QUERY_PROTOCOL_VERSION_OPERATION failed "
 273                            "(op %d status 0x%x)",
 274                            vstor_packet->operation, vstor_packet->status);
 275                 goto cleanup;
 276         }
 277
 278         /* Query channel properties */
 279         DPRINT_INFO(STORVSC, "QUERY_PROPERTIES_OPERATION...");
 280
 281         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 282         vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
 283         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 284         vstor_packet->storage_channel_properties.port_number =
 285                                         stor_device->port_number;
 286
 287         request->wait_condition = 0;
 288         ret = vmbus_sendpacket(device->channel, vstor_packet,
 289                                sizeof(struct vstor_packet),
 290                                (unsigned long)request,
 291                                VM_PKT_DATA_INBAND,
 292                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 293
 294         if (ret != 0) {
 295                 DPRINT_ERR(STORVSC,
 296                            "unable to send QUERY_PROPERTIES_OPERATION");
 297                 goto cleanup;
 298         }
 299
 300         wait_event_timeout(request->wait_event, request->wait_condition,
 301                         msecs_to_jiffies(1000));
 302         if (request->wait_condition == 0) {
 303                 ret = -ETIMEDOUT;
 304                 goto cleanup;
 305         }
 306
 307         /* TODO: Check returned version */
 308         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 309             vstor_packet->status != 0) {
 310                 DPRINT_ERR(STORVSC, "QUERY_PROPERTIES_OPERATION failed "
 311                            "(op %d status 0x%x)",
 312                            vstor_packet->operation, vstor_packet->status);
 313                 goto cleanup;
 314         }
 315
 316         stor_device->path_id = vstor_packet->storage_channel_properties.path_id;
 317         stor_device->target_id
 318                 = vstor_packet->storage_channel_properties.target_id;
 319
 320         DPRINT_DBG(STORVSC, "channel flag 0x%x, max xfer len 0x%x",
 321                    vstor_packet->storage_channel_properties.flags,
 322                    vstor_packet->storage_channel_properties.max_transfer_bytes);
 323
 324         DPRINT_INFO(STORVSC, "END_INITIALIZATION_OPERATION...");
 325
 326         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 327         vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
 328         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 329
 330         request->wait_condition = 0;
 331         ret = vmbus_sendpacket(device->channel, vstor_packet,
 332                                sizeof(struct vstor_packet),
 333                                (unsigned long)request,
 334                                VM_PKT_DATA_INBAND,
 335                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 336
 337         if (ret != 0) {
 338                 DPRINT_ERR(STORVSC,
 339                            "unable to send END_INITIALIZATION_OPERATION");
 340                 goto cleanup;
 341         }
 342
 343         wait_event_timeout(request->wait_event, request->wait_condition,
 344                         msecs_to_jiffies(1000));
 345         if (request->wait_condition == 0) {
 346                 ret = -ETIMEDOUT;
 347                 goto cleanup;
 348         }
 349
 350         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 351             vstor_packet->status != 0) {
 352                 DPRINT_ERR(STORVSC, "END_INITIALIZATION_OPERATION failed "
 353                            "(op %d status 0x%x)",
 354                            vstor_packet->operation, vstor_packet->status);
 355                 goto cleanup;
 356         }
 357
 358         DPRINT_INFO(STORVSC, "**** storage channel up and running!! ****");
 359
 360 cleanup:
 361         put_stor_device(device);
 362         return ret;
 363 }
 364
 365 static void stor_vsc_on_io_completion(struct hv_device *device,
 366                                   struct vstor_packet *vstor_packet,
 367                                   struct storvsc_request_extension *request_ext)
 368 {
 369         struct hv_storvsc_request *request;
 370         struct storvsc_device *stor_device;
 371
 372         stor_device = must_get_stor_device(device);
 373         if (!stor_device) {
 374                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 375                            "device being destroyed?");
 376                 return;
 377         }
 378
 379         DPRINT_DBG(STORVSC, "IO_COMPLETE_OPERATION - request extension %p "
 380                    "completed bytes xfer %u", request_ext,
 381                    vstor_packet->vm_srb.data_transfer_length);
 382
 383         /* ASSERT(request_ext != NULL); */
 384         /* ASSERT(request_ext->request != NULL); */
 385
 386         request = request_ext->request;
 387
 388         /* ASSERT(request->OnIOCompletion != NULL); */
 389
 390         /* Copy over the status...etc */
 391         request->status = vstor_packet->vm_srb.scsi_status;
 392
 393         if (request->status != 0 || vstor_packet->vm_srb.srb_status != 1) {
 394                 DPRINT_WARN(STORVSC,
 395                             "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
 396                             request->cdb[0], vstor_packet->vm_srb.scsi_status,
 397                             vstor_packet->vm_srb.srb_status);
 398         }
 399
 400         if ((request->status & 0xFF) == 0x02) {
 401                 /* CHECK_CONDITION */
 402                 if (vstor_packet->vm_srb.srb_status & 0x80) {
 403                         /* autosense data available */
 404                         DPRINT_WARN(STORVSC, "storvsc pkt %p autosense data "
 405                                     "valid - len %d\n", request_ext,
 406                                     vstor_packet->vm_srb.sense_info_length);
 407
 408                         /* ASSERT(vstor_packet->vm_srb.sense_info_length <= */
 409                         /*      request->SenseBufferSize); */
 410                         memcpy(request->sense_buffer,
 411                                vstor_packet->vm_srb.sense_data,
 412                                vstor_packet->vm_srb.sense_info_length);
 413
 414                         request->sense_buffer_size =
 415                                         vstor_packet->vm_srb.sense_info_length;
 416                 }
 417         }
 418
 419         /* TODO: */
 420         request->bytes_xfer = vstor_packet->vm_srb.data_transfer_length;
 421
 422         request->on_io_completion(request);
 423
 424         atomic_dec(&stor_device->num_outstanding_req);
 425
 426         put_stor_device(device);
 427 }
 428
 429 static void stor_vsc_on_receive(struct hv_device *device,
 430                              struct vstor_packet *vstor_packet,
 431                              struct storvsc_request_extension *request_ext)
 432 {
 433         switch (vstor_packet->operation) {
 434         case VSTOR_OPERATION_COMPLETE_IO:
 435                 DPRINT_DBG(STORVSC, "IO_COMPLETE_OPERATION");
 436                 stor_vsc_on_io_completion(device, vstor_packet, request_ext);
 437                 break;
 438         case VSTOR_OPERATION_REMOVE_DEVICE:
 439                 DPRINT_INFO(STORVSC, "REMOVE_DEVICE_OPERATION");
 440                 /* TODO: */
 441                 break;
 442
 443         default:
 444                 DPRINT_INFO(STORVSC, "Unknown operation received - %d",
 445                             vstor_packet->operation);
 446                 break;
 447         }
 448 }
 449
 450 static void stor_vsc_on_channel_callback(void *context)
 451 {
 452         struct hv_device *device = (struct hv_device *)context;
 453         struct storvsc_device *stor_device;
 454         u32 bytes_recvd;
 455         u64 request_id;
 456         unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
 457         struct storvsc_request_extension *request;
 458         int ret;
 459
 460         /* ASSERT(device); */
 461
 462         stor_device = must_get_stor_device(device);
 463         if (!stor_device) {
 464                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 465                            "device being destroyed?");
 466                 return;
 467         }
 468
 469         do {
 470                 ret = vmbus_recvpacket(device->channel, packet,
 471                                        ALIGN(sizeof(struct vstor_packet), 8),
 472                                        &bytes_recvd, &request_id);
 473                 if (ret == 0 && bytes_recvd > 0) {
 474                         DPRINT_DBG(STORVSC, "receive %d bytes - tid %llx",
 475                                    bytes_recvd, request_id);
 476
 477                         /* ASSERT(bytes_recvd ==
 478                                         sizeof(struct vstor_packet)); */
 479
 480                         request = (struct storvsc_request_extension *)
 481                                         (unsigned long)request_id;
 482                         /* ASSERT(request);c */
 483
 484                         /* if (vstor_packet.Flags & SYNTHETIC_FLAG) */
 485                         if ((request == &stor_device->init_request) ||
 486                             (request == &stor_device->reset_request)) {
 487                                 /* DPRINT_INFO(STORVSC,
 488                                  *             "reset completion - operation "
 489                                  *             "%u status %u",
 490                                  *             vstor_packet.Operation,
 491                                  *             vstor_packet.Status); */
 492
 493                                 memcpy(&request->vstor_packet, packet,
 494                                        sizeof(struct vstor_packet));
 495                                 request->wait_condition = 1;
 496                                 wake_up(&request->wait_event);
 497                         } else {
 498                                 stor_vsc_on_receive(device,
 499                                                 (struct vstor_packet *)packet,
 500                                                 request);
 501                         }
 502                 } else {
 503                         /* DPRINT_DBG(STORVSC, "nothing else to read..."); */
 504                         break;
 505                 }
 506         } while (1);
 507
 508         put_stor_device(device);
 509         return;
 510 }
 511
 512 static int stor_vsc_connect_to_vsp(struct hv_device *device)
 513 {
 514         struct vmstorage_channel_properties props;
 515         struct storvsc_driver_object *stor_driver;
 516         int ret;
 517
 518         stor_driver = (struct storvsc_driver_object *)device->drv;
 519         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
 520
 521         /* Open the channel */
 522         ret = vmbus_open(device->channel,
 523                          stor_driver->ring_buffer_size,
 524                          stor_driver->ring_buffer_size,
 525                          (void *)&props,
 526                          sizeof(struct vmstorage_channel_properties),
 527                          stor_vsc_on_channel_callback, device);
 528
 529         DPRINT_DBG(STORVSC, "storage props: path id %d, tgt id %d, max xfer %d",
 530                    props.path_id, props.target_id, props.max_transfer_bytes);
 531
 532         if (ret != 0) {
 533                 DPRINT_ERR(STORVSC, "unable to open channel: %d", ret);
 534                 return -1;
 535         }
 536
 537         ret = stor_vsc_channel_init(device);
 538
 539         return ret;
 540 }
 541
 542 /*
 543  * stor_vsc_on_device_add - Callback when the device belonging to this driver
 544  * is added
 545  */
 546 static int stor_vsc_on_device_add(struct hv_device *device,
 547                                         void *additional_info)
 548 {
 549         struct storvsc_device *stor_device;
 550         /* struct vmstorage_channel_properties *props; */
 551         struct storvsc_device_info *device_info;
 552         int ret = 0;
 553
 554         device_info = (struct storvsc_device_info *)additional_info;
 555         stor_device = alloc_stor_device(device);
 556         if (!stor_device) {
 557                 ret = -1;
 558                 goto cleanup;
 559         }
 560
 561         /* Save the channel properties to our storvsc channel */
 562         /* props = (struct vmstorage_channel_properties *)
 563          *              channel->offerMsg.Offer.u.Standard.UserDefined; */
 564
 565         /* FIXME: */
 566         /*
 567          * If we support more than 1 scsi channel, we need to set the
 568          * port number here to the scsi channel but how do we get the
 569          * scsi channel prior to the bus scan
 570          */
 571
 572         /* storChannel->PortNumber = 0;
 573         storChannel->PathId = props->PathId;
 574         storChannel->TargetId = props->TargetId; */
 575
 576         stor_device->port_number = device_info->port_number;
 577         /* Send it back up */
 578         ret = stor_vsc_connect_to_vsp(device);
 579
 580         /* device_info->PortNumber = stor_device->PortNumber; */
 581         device_info->path_id = stor_device->path_id;
 582         device_info->target_id = stor_device->target_id;
 583
 584         DPRINT_DBG(STORVSC, "assigned port %u, path %u target %u\n",
 585                    stor_device->port_number, stor_device->path_id,
 586                    stor_device->target_id);
 587
 588 cleanup:
 589         return ret;
 590 }
 591
 592 /*
 593  * stor_vsc_on_device_remove - Callback when the our device is being removed
 594  */
 595 static int stor_vsc_on_device_remove(struct hv_device *device)
 596 {
 597         struct storvsc_device *stor_device;
 598
 599         DPRINT_INFO(STORVSC, "disabling storage device (%p)...",
 600                     device->ext);
 601
 602         stor_device = release_stor_device(device);
 603
 604         /*
 605          * At this point, all outbound traffic should be disable. We
 606          * only allow inbound traffic (responses) to proceed so that
 607          * outstanding requests can be completed.
 608          */
 609         while (atomic_read(&stor_device->num_outstanding_req)) {
 610                 DPRINT_INFO(STORVSC, "waiting for %d requests to complete...",
 611                             atomic_read(&stor_device->num_outstanding_req));
 612                 udelay(100);
 613         }
 614
 615         DPRINT_INFO(STORVSC, "removing storage device (%p)...",
 616                     device->ext);
 617
 618         stor_device = final_release_stor_device(device);
 619
 620         DPRINT_INFO(STORVSC, "storage device (%p) safe to remove", stor_device);
 621
 622         /* Close the channel */
 623         vmbus_close(device->channel);
 624
 625         free_stor_device(stor_device);
 626         return 0;
 627 }
 628
 629 int stor_vsc_on_host_reset(struct hv_device *device)
 630 {
 631         struct storvsc_device *stor_device;
 632         struct storvsc_request_extension *request;
 633         struct vstor_packet *vstor_packet;
 634         int ret;
 635
 636         DPRINT_INFO(STORVSC, "resetting host adapter...");
 637
 638         stor_device = get_stor_device(device);
 639         if (!stor_device) {
 640                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 641                            "device being destroyed?");
 642                 return -1;
 643         }
 644
 645         request = &stor_device->reset_request;
 646         vstor_packet = &request->vstor_packet;
 647
 648         init_waitqueue_head(&request->wait_event);
 649
 650         vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
 651         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 652         vstor_packet->vm_srb.path_id = stor_device->path_id;
 653
 654         request->wait_condition = 0;
 655         ret = vmbus_sendpacket(device->channel, vstor_packet,
 656                                sizeof(struct vstor_packet),
 657                                (unsigned long)&stor_device->reset_request,
 658                                VM_PKT_DATA_INBAND,
 659                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 660         if (ret != 0) {
 661                 DPRINT_ERR(STORVSC, "Unable to send reset packet %p ret %d",
 662                            vstor_packet, ret);
 663                 goto cleanup;
 664         }
 665
 666         wait_event_timeout(request->wait_event, request->wait_condition,
 667                         msecs_to_jiffies(1000));
 668         if (request->wait_condition == 0) {
 669                 ret = -ETIMEDOUT;
 670                 goto cleanup;
 671         }
 672
 673         DPRINT_INFO(STORVSC, "host adapter reset completed");
 674
 675         /*
 676          * At this point, all outstanding requests in the adapter
 677          * should have been flushed out and return to us
 678          */
 679
 680 cleanup:
 681         put_stor_device(device);
 682         return ret;
 683 }
 684
 685 /*
 686  * stor_vsc_on_io_request - Callback to initiate an I/O request
 687  */
 688 static int stor_vsc_on_io_request(struct hv_device *device,
 689                               struct hv_storvsc_request *request)
 690 {
 691         struct storvsc_device *stor_device;
 692         struct storvsc_request_extension *request_extension;
 693         struct vstor_packet *vstor_packet;
 694         int ret = 0;
 695
 696         request_extension =
 697                 (struct storvsc_request_extension *)request->extension;
 698         vstor_packet = &request_extension->vstor_packet;
 699         stor_device = get_stor_device(device);
 700
 701         DPRINT_DBG(STORVSC, "enter - Device %p, DeviceExt %p, Request %p, "
 702                    "Extension %p", device, stor_device, request,
 703                    request_extension);
 704
 705         DPRINT_DBG(STORVSC, "req %p len %d bus %d, target %d, lun %d cdblen %d",
 706                    request, request->data_buffer.len, request->bus,
 707                    request->target_id, request->lun_id, request->cdb_len);
 708
 709         if (!stor_device) {
 710                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 711                            "device being destroyed?");
 712                 return -2;
 713         }
 714
 715         /* print_hex_dump_bytes("", DUMP_PREFIX_NONE, request->Cdb,
 716          *                      request->CdbLen); */
 717
 718         request_extension->request = request;
 719         request_extension->device  = device;
 720
 721         memset(vstor_packet, 0 , sizeof(struct vstor_packet));
 722
 723         vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
 724
 725         vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
 726
 727         vstor_packet->vm_srb.port_number = request->host;
 728         vstor_packet->vm_srb.path_id = request->bus;
 729         vstor_packet->vm_srb.target_id = request->target_id;
 730         vstor_packet->vm_srb.lun = request->lun_id;
 731
 732         vstor_packet->vm_srb.sense_info_length = SENSE_BUFFER_SIZE;
 733
 734         /* Copy over the scsi command descriptor block */
 735         vstor_packet->vm_srb.cdb_length = request->cdb_len;
 736         memcpy(&vstor_packet->vm_srb.cdb, request->cdb, request->cdb_len);
 737
 738         vstor_packet->vm_srb.data_in = request->type;
 739         vstor_packet->vm_srb.data_transfer_length = request->data_buffer.len;
 740
 741         vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
 742
 743         DPRINT_DBG(STORVSC, "srb - len %d port %d, path %d, target %d, "
 744                    "lun %d senselen %d cdblen %d",
 745                    vstor_packet->vm_srb.length,
 746                    vstor_packet->vm_srb.port_number,
 747                    vstor_packet->vm_srb.path_id,
 748                    vstor_packet->vm_srb.target_id,
 749                    vstor_packet->vm_srb.lun,
 750                    vstor_packet->vm_srb.sense_info_length,
 751                    vstor_packet->vm_srb.cdb_length);
 752
 753         if (request_extension->request->data_buffer.len) {
 754                 ret = vmbus_sendpacket_multipagebuffer(device->channel,
 755                                 &request_extension->request->data_buffer,
 756                                 vstor_packet,
 757                                 sizeof(struct vstor_packet),
 758                                 (unsigned long)request_extension);
 759         } else {
 760                 ret = vmbus_sendpacket(device->channel, vstor_packet,
 761                                        sizeof(struct vstor_packet),
 762                                        (unsigned long)request_extension,
 763                                        VM_PKT_DATA_INBAND,
 764                                        VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 765         }
 766
 767         if (ret != 0) {
 768                 DPRINT_DBG(STORVSC, "Unable to send packet %p ret %d",
 769                            vstor_packet, ret);
 770         }
 771
 772         atomic_inc(&stor_device->num_outstanding_req);
 773
 774         put_stor_device(device);
 775         return ret;
 776 }
 777
 778 /*
 779  * stor_vsc_on_cleanup - Perform any cleanup when the driver is removed
 780  */
 781 static void stor_vsc_on_cleanup(struct hv_driver *driver)
 782 {
 783 }
 784
 785 /*
 786  * stor_vsc_initialize - Main entry point
 787  */
 788 int stor_vsc_initialize(struct hv_driver *driver)
 789 {
 790         struct storvsc_driver_object *stor_driver;
 791
 792         stor_driver = (struct storvsc_driver_object *)driver;
 793
 794         DPRINT_DBG(STORVSC, "sizeof(STORVSC_REQUEST)=%zd "
 795                    "sizeof(struct storvsc_request_extension)=%zd "
 796                    "sizeof(struct vstor_packet)=%zd, "
 797                    "sizeof(struct vmscsi_request)=%zd",
 798                    sizeof(struct hv_storvsc_request),
 799                    sizeof(struct storvsc_request_extension),
 800                    sizeof(struct vstor_packet),
 801                    sizeof(struct vmscsi_request));
 802
 803         /* Make sure we are at least 2 pages since 1 page is used for control */
 804         /* ASSERT(stor_driver->RingBufferSize >= (PAGE_SIZE << 1)); */
 805
 806         driver->name = g_driver_name;
 807         memcpy(&driver->dev_type, &gStorVscDeviceType,
 808                sizeof(struct hv_guid));
 809
 810         stor_driver->request_ext_size =
 811                         sizeof(struct storvsc_request_extension);
 812
 813         /*
 814          * Divide the ring buffer data size (which is 1 page less
 815          * than the ring buffer size since that page is reserved for
 816          * the ring buffer indices) by the max request size (which is
 817          * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
 818          */
 819         stor_driver->max_outstanding_req_per_channel =
 820                 ((stor_driver->ring_buffer_size - PAGE_SIZE) /
 821                   ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
 822                            sizeof(struct vstor_packet) + sizeof(u64),
 823                            sizeof(u64)));
 824
 825         DPRINT_INFO(STORVSC, "max io %u, currently %u\n",
 826                     stor_driver->max_outstanding_req_per_channel,
 827                     STORVSC_MAX_IO_REQUESTS);
 828
 829         /* Setup the dispatch table */
 830         stor_driver->base.dev_add       = stor_vsc_on_device_add;
 831         stor_driver->base.dev_rm        = stor_vsc_on_device_remove;
 832         stor_driver->base.cleanup       = stor_vsc_on_cleanup;
 833
 834         stor_driver->on_io_request      = stor_vsc_on_io_request;
 835
 836         return 0;
 837 }