drivers/scsi/storvsc_drv.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  *   K. Y. Srinivasan <kys@microsoft.com>
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/wait.h>
  25 #include <linux/sched.h>
  26 #include <linux/completion.h>
  27 #include <linux/string.h>
  28 #include <linux/mm.h>
  29 #include <linux/delay.h>
  30 #include <linux/init.h>
  31 #include <linux/slab.h>
  32 #include <linux/module.h>
  33 #include <linux/device.h>
  34 #include <linux/hyperv.h>
  35 #include <linux/blkdev.h>
  36 #include <scsi/scsi.h>
  37 #include <scsi/scsi_cmnd.h>
  38 #include <scsi/scsi_host.h>
  39 #include <scsi/scsi_device.h>
  40 #include <scsi/scsi_tcq.h>
  41 #include <scsi/scsi_eh.h>
  42 #include <scsi/scsi_devinfo.h>
  43 #include <scsi/scsi_dbg.h>
  44 #include <scsi/scsi_transport_fc.h>
  45
  46 /*
  47  * All wire protocol details (storage protocol between the guest and the host)
  48  * are consolidated here.
  49  *
  50  * Begin protocol definitions.
  51  */
  52
  53 /*
  54  * Version history:
  55  * V1 Beta: 0.1
  56  * V1 RC < 2008/1/31: 1.0
  57  * V1 RC > 2008/1/31:  2.0
  58  * Win7: 4.2
  59  * Win8: 5.1
  60  * Win8.1: 6.0
  61  * Win10: 6.2
  62  */
  63
  64 #define VMSTOR_PROTO_VERSION(MAJOR_, MINOR_)    ((((MAJOR_) & 0xff) << 8) | \
  65                                                 (((MINOR_) & 0xff)))
  66
  67 #define VMSTOR_PROTO_VERSION_WIN6       VMSTOR_PROTO_VERSION(2, 0)
  68 #define VMSTOR_PROTO_VERSION_WIN7       VMSTOR_PROTO_VERSION(4, 2)
  69 #define VMSTOR_PROTO_VERSION_WIN8       VMSTOR_PROTO_VERSION(5, 1)
  70 #define VMSTOR_PROTO_VERSION_WIN8_1     VMSTOR_PROTO_VERSION(6, 0)
  71 #define VMSTOR_PROTO_VERSION_WIN10      VMSTOR_PROTO_VERSION(6, 2)
  72
  73 /*  Packet structure describing virtual storage requests. */
  74 enum vstor_packet_operation {
  75         VSTOR_OPERATION_COMPLETE_IO             = 1,
  76         VSTOR_OPERATION_REMOVE_DEVICE           = 2,
  77         VSTOR_OPERATION_EXECUTE_SRB             = 3,
  78         VSTOR_OPERATION_RESET_LUN               = 4,
  79         VSTOR_OPERATION_RESET_ADAPTER           = 5,
  80         VSTOR_OPERATION_RESET_BUS               = 6,
  81         VSTOR_OPERATION_BEGIN_INITIALIZATION    = 7,
  82         VSTOR_OPERATION_END_INITIALIZATION      = 8,
  83         VSTOR_OPERATION_QUERY_PROTOCOL_VERSION  = 9,
  84         VSTOR_OPERATION_QUERY_PROPERTIES        = 10,
  85         VSTOR_OPERATION_ENUMERATE_BUS           = 11,
  86         VSTOR_OPERATION_FCHBA_DATA              = 12,
  87         VSTOR_OPERATION_CREATE_SUB_CHANNELS     = 13,
  88         VSTOR_OPERATION_MAXIMUM                 = 13
  89 };
  90
  91 /*
  92  * WWN packet for Fibre Channel HBA
  93  */
  94
  95 struct hv_fc_wwn_packet {
  96         u8      primary_active;
  97         u8      reserved1[3];
  98         u8      primary_port_wwn[8];
  99         u8      primary_node_wwn[8];
 100         u8      secondary_port_wwn[8];
 101         u8      secondary_node_wwn[8];
 102 };
 103
 104
 105
 106 /*
 107  * SRB Flag Bits
 108  */
 109
 110 #define SRB_FLAGS_QUEUE_ACTION_ENABLE           0x00000002
 111 #define SRB_FLAGS_DISABLE_DISCONNECT            0x00000004
 112 #define SRB_FLAGS_DISABLE_SYNCH_TRANSFER        0x00000008
 113 #define SRB_FLAGS_BYPASS_FROZEN_QUEUE           0x00000010
 114 #define SRB_FLAGS_DISABLE_AUTOSENSE             0x00000020
 115 #define SRB_FLAGS_DATA_IN                       0x00000040
 116 #define SRB_FLAGS_DATA_OUT                      0x00000080
 117 #define SRB_FLAGS_NO_DATA_TRANSFER              0x00000000
 118 #define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT)
 119 #define SRB_FLAGS_NO_QUEUE_FREEZE               0x00000100
 120 #define SRB_FLAGS_ADAPTER_CACHE_ENABLE          0x00000200
 121 #define SRB_FLAGS_FREE_SENSE_BUFFER             0x00000400
 122
 123 /*
 124  * This flag indicates the request is part of the workflow for processing a D3.
 125  */
 126 #define SRB_FLAGS_D3_PROCESSING                 0x00000800
 127 #define SRB_FLAGS_IS_ACTIVE                     0x00010000
 128 #define SRB_FLAGS_ALLOCATED_FROM_ZONE           0x00020000
 129 #define SRB_FLAGS_SGLIST_FROM_POOL              0x00040000
 130 #define SRB_FLAGS_BYPASS_LOCKED_QUEUE           0x00080000
 131 #define SRB_FLAGS_NO_KEEP_AWAKE                 0x00100000
 132 #define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE        0x00200000
 133 #define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT      0x00400000
 134 #define SRB_FLAGS_DONT_START_NEXT_PACKET        0x00800000
 135 #define SRB_FLAGS_PORT_DRIVER_RESERVED          0x0F000000
 136 #define SRB_FLAGS_CLASS_DRIVER_RESERVED         0xF0000000
 137
 138
 139 /*
 140  * Platform neutral description of a scsi request -
 141  * this remains the same across the write regardless of 32/64 bit
 142  * note: it's patterned off the SCSI_PASS_THROUGH structure
 143  */
 144 #define STORVSC_MAX_CMD_LEN                     0x10
 145
 146 #define POST_WIN7_STORVSC_SENSE_BUFFER_SIZE     0x14
 147 #define PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE      0x12
 148
 149 #define STORVSC_SENSE_BUFFER_SIZE               0x14
 150 #define STORVSC_MAX_BUF_LEN_WITH_PADDING        0x14
 151
 152 /*
 153  * Sense buffer size changed in win8; have a run-time
 154  * variable to track the size we should use.  This value will
 155  * likely change during protocol negotiation but it is valid
 156  * to start by assuming pre-Win8.
 157  */
 158 static int sense_buffer_size = PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE;
 159
 160 /*
 161  * The storage protocol version is determined during the
 162  * initial exchange with the host.  It will indicate which
 163  * storage functionality is available in the host.
 164 */
 165 static int vmstor_proto_version;
 166
 167 #define STORVSC_LOGGING_NONE    0
 168 #define STORVSC_LOGGING_ERROR   1
 169 #define STORVSC_LOGGING_WARN    2
 170
 171 static int logging_level = STORVSC_LOGGING_ERROR;
 172 module_param(logging_level, int, S_IRUGO|S_IWUSR);
 173 MODULE_PARM_DESC(logging_level,
 174         "Logging level, 0 - None, 1 - Error (default), 2 - Warning.");
 175
 176 static inline bool do_logging(int level)
 177 {
 178         return logging_level >= level;
 179 }
 180
 181 #define storvsc_log(dev, level, fmt, ...)                       \
 182 do {                                                            \
 183         if (do_logging(level))                                  \
 184                 dev_warn(&(dev)->device, fmt, ##__VA_ARGS__);   \
 185 } while (0)
 186
 187 struct vmscsi_win8_extension {
 188         /*
 189          * The following were added in Windows 8
 190          */
 191         u16 reserve;
 192         u8  queue_tag;
 193         u8  queue_action;
 194         u32 srb_flags;
 195         u32 time_out_value;
 196         u32 queue_sort_ey;
 197 } __packed;
 198
 199 struct vmscsi_request {
 200         u16 length;
 201         u8 srb_status;
 202         u8 scsi_status;
 203
 204         u8  port_number;
 205         u8  path_id;
 206         u8  target_id;
 207         u8  lun;
 208
 209         u8  cdb_length;
 210         u8  sense_info_length;
 211         u8  data_in;
 212         u8  reserved;
 213
 214         u32 data_transfer_length;
 215
 216         union {
 217                 u8 cdb[STORVSC_MAX_CMD_LEN];
 218                 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
 219                 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
 220         };
 221         /*
 222          * The following was added in win8.
 223          */
 224         struct vmscsi_win8_extension win8_extension;
 225
 226 } __attribute((packed));
 227
 228
 229 /*
 230  * The size of the vmscsi_request has changed in win8. The
 231  * additional size is because of new elements added to the
 232  * structure. These elements are valid only when we are talking
 233  * to a win8 host.
 234  * Track the correction to size we need to apply. This value
 235  * will likely change during protocol negotiation but it is
 236  * valid to start by assuming pre-Win8.
 237  */
 238 static int vmscsi_size_delta = sizeof(struct vmscsi_win8_extension);
 239
 240 /*
 241  * The list of storage protocols in order of preference.
 242  */
 243 struct vmstor_protocol {
 244         int protocol_version;
 245         int sense_buffer_size;
 246         int vmscsi_size_delta;
 247 };
 248
 249
 250 static const struct vmstor_protocol vmstor_protocols[] = {
 251         {
 252                 VMSTOR_PROTO_VERSION_WIN10,
 253                 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
 254                 0
 255         },
 256         {
 257                 VMSTOR_PROTO_VERSION_WIN8_1,
 258                 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
 259                 0
 260         },
 261         {
 262                 VMSTOR_PROTO_VERSION_WIN8,
 263                 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
 264                 0
 265         },
 266         {
 267                 VMSTOR_PROTO_VERSION_WIN7,
 268                 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
 269                 sizeof(struct vmscsi_win8_extension),
 270         },
 271         {
 272                 VMSTOR_PROTO_VERSION_WIN6,
 273                 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
 274                 sizeof(struct vmscsi_win8_extension),
 275         }
 276 };
 277
 278
 279 /*
 280  * This structure is sent during the intialization phase to get the different
 281  * properties of the channel.
 282  */
 283
 284 #define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL          0x1
 285
 286 struct vmstorage_channel_properties {
 287         u32 reserved;
 288         u16 max_channel_cnt;
 289         u16 reserved1;
 290
 291         u32 flags;
 292         u32   max_transfer_bytes;
 293
 294         u64  reserved2;
 295 } __packed;
 296
 297 /*  This structure is sent during the storage protocol negotiations. */
 298 struct vmstorage_protocol_version {
 299         /* Major (MSW) and minor (LSW) version numbers. */
 300         u16 major_minor;
 301
 302         /*
 303          * Revision number is auto-incremented whenever this file is changed
 304          * (See FILL_VMSTOR_REVISION macro above).  Mismatch does not
 305          * definitely indicate incompatibility--but it does indicate mismatched
 306          * builds.
 307          * This is only used on the windows side. Just set it to 0.
 308          */
 309         u16 revision;
 310 } __packed;
 311
 312 /* Channel Property Flags */
 313 #define STORAGE_CHANNEL_REMOVABLE_FLAG          0x1
 314 #define STORAGE_CHANNEL_EMULATED_IDE_FLAG       0x2
 315
 316 struct vstor_packet {
 317         /* Requested operation type */
 318         enum vstor_packet_operation operation;
 319
 320         /*  Flags - see below for values */
 321         u32 flags;
 322
 323         /* Status of the request returned from the server side. */
 324         u32 status;
 325
 326         /* Data payload area */
 327         union {
 328                 /*
 329                  * Structure used to forward SCSI commands from the
 330                  * client to the server.
 331                  */
 332                 struct vmscsi_request vm_srb;
 333
 334                 /* Structure used to query channel properties. */
 335                 struct vmstorage_channel_properties storage_channel_properties;
 336
 337                 /* Used during version negotiations. */
 338                 struct vmstorage_protocol_version version;
 339
 340                 /* Fibre channel address packet */
 341                 struct hv_fc_wwn_packet wwn_packet;
 342
 343                 /* Number of sub-channels to create */
 344                 u16 sub_channel_count;
 345
 346                 /* This will be the maximum of the union members */
 347                 u8  buffer[0x34];
 348         };
 349 } __packed;
 350
 351 /*
 352  * Packet Flags:
 353  *
 354  * This flag indicates that the server should send back a completion for this
 355  * packet.
 356  */
 357
 358 #define REQUEST_COMPLETION_FLAG 0x1
 359
 360 /* Matches Windows-end */
 361 enum storvsc_request_type {
 362         WRITE_TYPE = 0,
 363         READ_TYPE,
 364         UNKNOWN_TYPE,
 365 };
 366
 367 /*
 368  * SRB status codes and masks; a subset of the codes used here.
 369  */
 370
 371 #define SRB_STATUS_AUTOSENSE_VALID      0x80
 372 #define SRB_STATUS_QUEUE_FROZEN         0x40
 373 #define SRB_STATUS_INVALID_LUN  0x20
 374 #define SRB_STATUS_SUCCESS      0x01
 375 #define SRB_STATUS_ABORTED      0x02
 376 #define SRB_STATUS_ERROR        0x04
 377
 378 #define SRB_STATUS(status) \
 379         (status & ~(SRB_STATUS_AUTOSENSE_VALID | SRB_STATUS_QUEUE_FROZEN))
 380 /*
 381  * This is the end of Protocol specific defines.
 382  */
 383
 384 static int storvsc_ringbuffer_size = (256 * PAGE_SIZE);
 385 static u32 max_outstanding_req_per_channel;
 386
 387 static int storvsc_vcpus_per_sub_channel = 4;
 388
 389 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
 390 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
 391
 392 module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
 393 MODULE_PARM_DESC(vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
 394 /*
 395  * Timeout in seconds for all devices managed by this driver.
 396  */
 397 static int storvsc_timeout = 180;
 398
 399 static int msft_blist_flags = BLIST_TRY_VPD_PAGES;
 400
 401 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
 402 static struct scsi_transport_template *fc_transport_template;
 403 #endif
 404
 405 static void storvsc_on_channel_callback(void *context);
 406
 407 #define STORVSC_MAX_LUNS_PER_TARGET                     255
 408 #define STORVSC_MAX_TARGETS                             2
 409 #define STORVSC_MAX_CHANNELS                            8
 410
 411 #define STORVSC_FC_MAX_LUNS_PER_TARGET                  255
 412 #define STORVSC_FC_MAX_TARGETS                          128
 413 #define STORVSC_FC_MAX_CHANNELS                         8
 414
 415 #define STORVSC_IDE_MAX_LUNS_PER_TARGET                 64
 416 #define STORVSC_IDE_MAX_TARGETS                         1
 417 #define STORVSC_IDE_MAX_CHANNELS                        1
 418
 419 struct storvsc_cmd_request {
 420         struct scsi_cmnd *cmd;
 421
 422         struct hv_device *device;
 423
 424         /* Synchronize the request/response if needed */
 425         struct completion wait_event;
 426
 427         struct vmbus_channel_packet_multipage_buffer mpb;
 428         struct vmbus_packet_mpb_array *payload;
 429         u32 payload_sz;
 430
 431         struct vstor_packet vstor_packet;
 432 };
 433
 434
 435 /* A storvsc device is a device object that contains a vmbus channel */
 436 struct storvsc_device {
 437         struct hv_device *device;
 438
 439         bool     destroy;
 440         bool     drain_notify;
 441         bool     open_sub_channel;
 442         atomic_t num_outstanding_req;
 443         struct Scsi_Host *host;
 444
 445         wait_queue_head_t waiting_to_drain;
 446
 447         /*
 448          * Each unique Port/Path/Target represents 1 channel ie scsi
 449          * controller. In reality, the pathid, targetid is always 0
 450          * and the port is set by us
 451          */
 452         unsigned int port_number;
 453         unsigned char path_id;
 454         unsigned char target_id;
 455
 456         /*
 457          * Max I/O, the device can support.
 458          */
 459         u32   max_transfer_bytes;
 460         /* Used for vsc/vsp channel reset process */
 461         struct storvsc_cmd_request init_request;
 462         struct storvsc_cmd_request reset_request;
 463         /*
 464          * Currently active port and node names for FC devices.
 465          */
 466         u64 node_name;
 467         u64 port_name;
 468 };
 469
 470 struct hv_host_device {
 471         struct hv_device *dev;
 472         unsigned int port;
 473         unsigned char path;
 474         unsigned char target;
 475 };
 476
 477 struct storvsc_scan_work {
 478         struct work_struct work;
 479         struct Scsi_Host *host;
 480         uint lun;
 481 };
 482
 483 static void storvsc_device_scan(struct work_struct *work)
 484 {
 485         struct storvsc_scan_work *wrk;
 486         uint lun;
 487         struct scsi_device *sdev;
 488
 489         wrk = container_of(work, struct storvsc_scan_work, work);
 490         lun = wrk->lun;
 491
 492         sdev = scsi_device_lookup(wrk->host, 0, 0, lun);
 493         if (!sdev)
 494                 goto done;
 495         scsi_rescan_device(&sdev->sdev_gendev);
 496         scsi_device_put(sdev);
 497
 498 done:
 499         kfree(wrk);
 500 }
 501
 502 static void storvsc_host_scan(struct work_struct *work)
 503 {
 504         struct storvsc_scan_work *wrk;
 505         struct Scsi_Host *host;
 506         struct scsi_device *sdev;
 507
 508         wrk = container_of(work, struct storvsc_scan_work, work);
 509         host = wrk->host;
 510
 511         /*
 512          * Before scanning the host, first check to see if any of the
 513          * currrently known devices have been hot removed. We issue a
 514          * "unit ready" command against all currently known devices.
 515          * This I/O will result in an error for devices that have been
 516          * removed. As part of handling the I/O error, we remove the device.
 517          *
 518          * When a LUN is added or removed, the host sends us a signal to
 519          * scan the host. Thus we are forced to discover the LUNs that
 520          * may have been removed this way.
 521          */
 522         mutex_lock(&host->scan_mutex);
 523         shost_for_each_device(sdev, host)
 524                 scsi_test_unit_ready(sdev, 1, 1, NULL);
 525         mutex_unlock(&host->scan_mutex);
 526         /*
 527          * Now scan the host to discover LUNs that may have been added.
 528          */
 529         scsi_scan_host(host);
 530
 531         kfree(wrk);
 532 }
 533
 534 static void storvsc_remove_lun(struct work_struct *work)
 535 {
 536         struct storvsc_scan_work *wrk;
 537         struct scsi_device *sdev;
 538
 539         wrk = container_of(work, struct storvsc_scan_work, work);
 540         if (!scsi_host_get(wrk->host))
 541                 goto done;
 542
 543         sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
 544
 545         if (sdev) {
 546                 scsi_remove_device(sdev);
 547                 scsi_device_put(sdev);
 548         }
 549         scsi_host_put(wrk->host);
 550
 551 done:
 552         kfree(wrk);
 553 }
 554
 555
 556 /*
 557  * We can get incoming messages from the host that are not in response to
 558  * messages that we have sent out. An example of this would be messages
 559  * received by the guest to notify dynamic addition/removal of LUNs. To
 560  * deal with potential race conditions where the driver may be in the
 561  * midst of being unloaded when we might receive an unsolicited message
 562  * from the host, we have implemented a mechanism to gurantee sequential
 563  * consistency:
 564  *
 565  * 1) Once the device is marked as being destroyed, we will fail all
 566  *    outgoing messages.
 567  * 2) We permit incoming messages when the device is being destroyed,
 568  *    only to properly account for messages already sent out.
 569  */
 570
 571 static inline struct storvsc_device *get_out_stor_device(
 572                                         struct hv_device *device)
 573 {
 574         struct storvsc_device *stor_device;
 575
 576         stor_device = hv_get_drvdata(device);
 577
 578         if (stor_device && stor_device->destroy)
 579                 stor_device = NULL;
 580
 581         return stor_device;
 582 }
 583
 584
 585 static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
 586 {
 587         dev->drain_notify = true;
 588         wait_event(dev->waiting_to_drain,
 589                    atomic_read(&dev->num_outstanding_req) == 0);
 590         dev->drain_notify = false;
 591 }
 592
 593 static inline struct storvsc_device *get_in_stor_device(
 594                                         struct hv_device *device)
 595 {
 596         struct storvsc_device *stor_device;
 597
 598         stor_device = hv_get_drvdata(device);
 599
 600         if (!stor_device)
 601                 goto get_in_err;
 602
 603         /*
 604          * If the device is being destroyed; allow incoming
 605          * traffic only to cleanup outstanding requests.
 606          */
 607
 608         if (stor_device->destroy  &&
 609                 (atomic_read(&stor_device->num_outstanding_req) == 0))
 610                 stor_device = NULL;
 611
 612 get_in_err:
 613         return stor_device;
 614
 615 }
 616
 617 static void handle_sc_creation(struct vmbus_channel *new_sc)
 618 {
 619         struct hv_device *device = new_sc->primary_channel->device_obj;
 620         struct storvsc_device *stor_device;
 621         struct vmstorage_channel_properties props;
 622
 623         stor_device = get_out_stor_device(device);
 624         if (!stor_device)
 625                 return;
 626
 627         if (stor_device->open_sub_channel == false)
 628                 return;
 629
 630         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
 631
 632         vmbus_open(new_sc,
 633                    storvsc_ringbuffer_size,
 634                    storvsc_ringbuffer_size,
 635                    (void *)&props,
 636                    sizeof(struct vmstorage_channel_properties),
 637                    storvsc_on_channel_callback, new_sc);
 638 }
 639
 640 static void  handle_multichannel_storage(struct hv_device *device, int max_chns)
 641 {
 642         struct storvsc_device *stor_device;
 643         int num_cpus = num_online_cpus();
 644         int num_sc;
 645         struct storvsc_cmd_request *request;
 646         struct vstor_packet *vstor_packet;
 647         int ret, t;
 648
 649         num_sc = ((max_chns > num_cpus) ? num_cpus : max_chns);
 650         stor_device = get_out_stor_device(device);
 651         if (!stor_device)
 652                 return;
 653
 654         request = &stor_device->init_request;
 655         vstor_packet = &request->vstor_packet;
 656
 657         stor_device->open_sub_channel = true;
 658         /*
 659          * Establish a handler for dealing with subchannels.
 660          */
 661         vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
 662
 663         /*
 664          * Check to see if sub-channels have already been created. This
 665          * can happen when this driver is re-loaded after unloading.
 666          */
 667
 668         if (vmbus_are_subchannels_present(device->channel))
 669                 return;
 670
 671         stor_device->open_sub_channel = false;
 672         /*
 673          * Request the host to create sub-channels.
 674          */
 675         memset(request, 0, sizeof(struct storvsc_cmd_request));
 676         init_completion(&request->wait_event);
 677         vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
 678         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 679         vstor_packet->sub_channel_count = num_sc;
 680
 681         ret = vmbus_sendpacket(device->channel, vstor_packet,
 682                                (sizeof(struct vstor_packet) -
 683                                vmscsi_size_delta),
 684                                (unsigned long)request,
 685                                VM_PKT_DATA_INBAND,
 686                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 687
 688         if (ret != 0)
 689                 return;
 690
 691         t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
 692         if (t == 0)
 693                 return;
 694
 695         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 696             vstor_packet->status != 0)
 697                 return;
 698
 699         /*
 700          * Now that we created the sub-channels, invoke the check; this
 701          * may trigger the callback.
 702          */
 703         stor_device->open_sub_channel = true;
 704         vmbus_are_subchannels_present(device->channel);
 705 }
 706
 707 static void cache_wwn(struct storvsc_device *stor_device,
 708                       struct vstor_packet *vstor_packet)
 709 {
 710         /*
 711          * Cache the currently active port and node ww names.
 712          */
 713         if (vstor_packet->wwn_packet.primary_active) {
 714                 stor_device->node_name =
 715                         wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
 716                 stor_device->port_name =
 717                         wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
 718         } else {
 719                 stor_device->node_name =
 720                         wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
 721                 stor_device->port_name =
 722                         wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
 723         }
 724 }
 725
 726
 727 static int storvsc_execute_vstor_op(struct hv_device *device,
 728                                     struct storvsc_cmd_request *request,
 729                                     bool status_check)
 730 {
 731         struct vstor_packet *vstor_packet;
 732         int ret, t;
 733
 734         vstor_packet = &request->vstor_packet;
 735
 736         init_completion(&request->wait_event);
 737         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 738
 739         ret = vmbus_sendpacket(device->channel, vstor_packet,
 740                                (sizeof(struct vstor_packet) -
 741                                vmscsi_size_delta),
 742                                (unsigned long)request,
 743                                VM_PKT_DATA_INBAND,
 744                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 745         if (ret != 0)
 746                 return ret;
 747
 748         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
 749         if (t == 0)
 750                 return -ETIMEDOUT;
 751
 752         if (!status_check)
 753                 return ret;
 754
 755         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 756             vstor_packet->status != 0)
 757                 return -EINVAL;
 758
 759         return ret;
 760 }
 761
 762 static int storvsc_channel_init(struct hv_device *device, bool is_fc)
 763 {
 764         struct storvsc_device *stor_device;
 765         struct storvsc_cmd_request *request;
 766         struct vstor_packet *vstor_packet;
 767         int ret, i;
 768         int max_chns;
 769         bool process_sub_channels = false;
 770
 771         stor_device = get_out_stor_device(device);
 772         if (!stor_device)
 773                 return -ENODEV;
 774
 775         request = &stor_device->init_request;
 776         vstor_packet = &request->vstor_packet;
 777
 778         /*
 779          * Now, initiate the vsc/vsp initialization protocol on the open
 780          * channel
 781          */
 782         memset(request, 0, sizeof(struct storvsc_cmd_request));
 783         vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
 784         ret = storvsc_execute_vstor_op(device, request, true);
 785         if (ret)
 786                 return ret;
 787         /*
 788          * Query host supported protocol version.
 789          */
 790
 791         for (i = 0; i < ARRAY_SIZE(vmstor_protocols); i++) {
 792                 /* reuse the packet for version range supported */
 793                 memset(vstor_packet, 0, sizeof(struct vstor_packet));
 794                 vstor_packet->operation =
 795                         VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
 796
 797                 vstor_packet->version.major_minor =
 798                         vmstor_protocols[i].protocol_version;
 799
 800                 /*
 801                  * The revision number is only used in Windows; set it to 0.
 802                  */
 803                 vstor_packet->version.revision = 0;
 804                 ret = storvsc_execute_vstor_op(device, request, false);
 805                 if (ret != 0)
 806                         return ret;
 807
 808                 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
 809                         return -EINVAL;
 810
 811                 if (vstor_packet->status == 0) {
 812                         vmstor_proto_version =
 813                                 vmstor_protocols[i].protocol_version;
 814
 815                         sense_buffer_size =
 816                                 vmstor_protocols[i].sense_buffer_size;
 817
 818                         vmscsi_size_delta =
 819                                 vmstor_protocols[i].vmscsi_size_delta;
 820
 821                         break;
 822                 }
 823         }
 824
 825         if (vstor_packet->status != 0)
 826                 return -EINVAL;
 827
 828
 829         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 830         vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
 831         ret = storvsc_execute_vstor_op(device, request, true);
 832         if (ret != 0)
 833                 return ret;
 834
 835         /*
 836          * Check to see if multi-channel support is there.
 837          * Hosts that implement protocol version of 5.1 and above
 838          * support multi-channel.
 839          */
 840         max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
 841         if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN8) {
 842                 if (vstor_packet->storage_channel_properties.flags &
 843                     STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
 844                         process_sub_channels = true;
 845         }
 846         stor_device->max_transfer_bytes =
 847                 vstor_packet->storage_channel_properties.max_transfer_bytes;
 848
 849         if (!is_fc)
 850                 goto done;
 851
 852         /*
 853          * For FC devices retrieve FC HBA data.
 854          */
 855         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 856         vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
 857         ret = storvsc_execute_vstor_op(device, request, true);
 858         if (ret != 0)
 859                 return ret;
 860
 861         /*
 862          * Cache the currently active port and node ww names.
 863          */
 864         cache_wwn(stor_device, vstor_packet);
 865
 866 done:
 867
 868         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 869         vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
 870         ret = storvsc_execute_vstor_op(device, request, true);
 871         if (ret != 0)
 872                 return ret;
 873
 874         if (process_sub_channels)
 875                 handle_multichannel_storage(device, max_chns);
 876
 877         return ret;
 878 }
 879
 880 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
 881                                 struct scsi_cmnd *scmnd,
 882                                 struct Scsi_Host *host,
 883                                 u8 asc, u8 ascq)
 884 {
 885         struct storvsc_scan_work *wrk;
 886         void (*process_err_fn)(struct work_struct *work);
 887         bool do_work = false;
 888
 889         switch (SRB_STATUS(vm_srb->srb_status)) {
 890         case SRB_STATUS_ERROR:
 891                 /*
 892                  * If there is an error; offline the device since all
 893                  * error recovery strategies would have already been
 894                  * deployed on the host side. However, if the command
 895                  * were a pass-through command deal with it appropriately.
 896                  */
 897                 switch (scmnd->cmnd[0]) {
 898                 case ATA_16:
 899                 case ATA_12:
 900                         set_host_byte(scmnd, DID_PASSTHROUGH);
 901                         break;
 902                 /*
 903                  * On Some Windows hosts TEST_UNIT_READY command can return
 904                  * SRB_STATUS_ERROR, let the upper level code deal with it
 905                  * based on the sense information.
 906                  */
 907                 case TEST_UNIT_READY:
 908                         break;
 909                 default:
 910                         set_host_byte(scmnd, DID_TARGET_FAILURE);
 911                 }
 912                 break;
 913         case SRB_STATUS_INVALID_LUN:
 914                 do_work = true;
 915                 process_err_fn = storvsc_remove_lun;
 916                 break;
 917         case (SRB_STATUS_ABORTED | SRB_STATUS_AUTOSENSE_VALID):
 918                 if ((asc == 0x2a) && (ascq == 0x9)) {
 919                         do_work = true;
 920                         process_err_fn = storvsc_device_scan;
 921                         /*
 922                          * Retry the I/O that trigerred this.
 923                          */
 924                         set_host_byte(scmnd, DID_REQUEUE);
 925                 }
 926                 break;
 927         }
 928
 929         if (!do_work)
 930                 return;
 931
 932         /*
 933          * We need to schedule work to process this error; schedule it.
 934          */
 935         wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
 936         if (!wrk) {
 937                 set_host_byte(scmnd, DID_TARGET_FAILURE);
 938                 return;
 939         }
 940
 941         wrk->host = host;
 942         wrk->lun = vm_srb->lun;
 943         INIT_WORK(&wrk->work, process_err_fn);
 944         schedule_work(&wrk->work);
 945 }
 946
 947
 948 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
 949                                        struct storvsc_device *stor_dev)
 950 {
 951         struct scsi_cmnd *scmnd = cmd_request->cmd;
 952         struct scsi_sense_hdr sense_hdr;
 953         struct vmscsi_request *vm_srb;
 954         struct Scsi_Host *host;
 955         u32 payload_sz = cmd_request->payload_sz;
 956         void *payload = cmd_request->payload;
 957
 958         host = stor_dev->host;
 959
 960         vm_srb = &cmd_request->vstor_packet.vm_srb;
 961
 962         scmnd->result = vm_srb->scsi_status;
 963
 964         if (scmnd->result) {
 965                 if (scsi_normalize_sense(scmnd->sense_buffer,
 966                                 SCSI_SENSE_BUFFERSIZE, &sense_hdr) &&
 967                     do_logging(STORVSC_LOGGING_ERROR))
 968                         scsi_print_sense_hdr(scmnd->device, "storvsc",
 969                                              &sense_hdr);
 970         }
 971
 972         if (vm_srb->srb_status != SRB_STATUS_SUCCESS)
 973                 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
 974                                          sense_hdr.ascq);
 975
 976         scsi_set_resid(scmnd,
 977                 cmd_request->payload->range.len -
 978                 vm_srb->data_transfer_length);
 979
 980         scmnd->scsi_done(scmnd);
 981
 982         if (payload_sz >
 983                 sizeof(struct vmbus_channel_packet_multipage_buffer))
 984                 kfree(payload);
 985 }
 986
 987 static void storvsc_on_io_completion(struct storvsc_device *stor_device,
 988                                   struct vstor_packet *vstor_packet,
 989                                   struct storvsc_cmd_request *request)
 990 {
 991         struct vstor_packet *stor_pkt;
 992         struct hv_device *device = stor_device->device;
 993
 994         stor_pkt = &request->vstor_packet;
 995
 996         /*
 997          * The current SCSI handling on the host side does
 998          * not correctly handle:
 999          * INQUIRY command with page code parameter set to 0x80
1000          * MODE_SENSE command with cmd[2] == 0x1c
1001          *
1002          * Setup srb and scsi status so this won't be fatal.
1003          * We do this so we can distinguish truly fatal failues
1004          * (srb status == 0x4) and off-line the device in that case.
1005          */
1006
1007         if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1008            (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1009                 vstor_packet->vm_srb.scsi_status = 0;
1010                 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1011         }
1012
1013
1014         /* Copy over the status...etc */
1015         stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1016         stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1017         stor_pkt->vm_srb.sense_info_length =
1018         vstor_packet->vm_srb.sense_info_length;
1019
1020         if (vstor_packet->vm_srb.scsi_status != 0 ||
1021             vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS)
1022                 storvsc_log(device, STORVSC_LOGGING_WARN,
1023                         "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
1024                         stor_pkt->vm_srb.cdb[0],
1025                         vstor_packet->vm_srb.scsi_status,
1026                         vstor_packet->vm_srb.srb_status);
1027
1028         if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
1029                 /* CHECK_CONDITION */
1030                 if (vstor_packet->vm_srb.srb_status &
1031                         SRB_STATUS_AUTOSENSE_VALID) {
1032                         /* autosense data available */
1033
1034                         storvsc_log(device, STORVSC_LOGGING_WARN,
1035                                 "stor pkt %p autosense data valid - len %d\n",
1036                                 request, vstor_packet->vm_srb.sense_info_length);
1037
1038                         memcpy(request->cmd->sense_buffer,
1039                                vstor_packet->vm_srb.sense_data,
1040                                vstor_packet->vm_srb.sense_info_length);
1041
1042                 }
1043         }
1044
1045         stor_pkt->vm_srb.data_transfer_length =
1046         vstor_packet->vm_srb.data_transfer_length;
1047
1048         storvsc_command_completion(request, stor_device);
1049
1050         if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1051                 stor_device->drain_notify)
1052                 wake_up(&stor_device->waiting_to_drain);
1053
1054
1055 }
1056
1057 static void storvsc_on_receive(struct storvsc_device *stor_device,
1058                              struct vstor_packet *vstor_packet,
1059                              struct storvsc_cmd_request *request)
1060 {
1061         struct storvsc_scan_work *work;
1062
1063         switch (vstor_packet->operation) {
1064         case VSTOR_OPERATION_COMPLETE_IO:
1065                 storvsc_on_io_completion(stor_device, vstor_packet, request);
1066                 break;
1067
1068         case VSTOR_OPERATION_REMOVE_DEVICE:
1069         case VSTOR_OPERATION_ENUMERATE_BUS:
1070                 work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1071                 if (!work)
1072                         return;
1073
1074                 INIT_WORK(&work->work, storvsc_host_scan);
1075                 work->host = stor_device->host;
1076                 schedule_work(&work->work);
1077                 break;
1078
1079         case VSTOR_OPERATION_FCHBA_DATA:
1080                 cache_wwn(stor_device, vstor_packet);
1081 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1082                 fc_host_node_name(stor_device->host) = stor_device->node_name;
1083                 fc_host_port_name(stor_device->host) = stor_device->port_name;
1084 #endif
1085                 break;
1086         default:
1087                 break;
1088         }
1089 }
1090
1091 static void storvsc_on_channel_callback(void *context)
1092 {
1093         struct vmbus_channel *channel = (struct vmbus_channel *)context;
1094         struct hv_device *device;
1095         struct storvsc_device *stor_device;
1096         u32 bytes_recvd;
1097         u64 request_id;
1098         unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
1099         struct storvsc_cmd_request *request;
1100         int ret;
1101
1102         if (channel->primary_channel != NULL)
1103                 device = channel->primary_channel->device_obj;
1104         else
1105                 device = channel->device_obj;
1106
1107         stor_device = get_in_stor_device(device);
1108         if (!stor_device)
1109                 return;
1110
1111         do {
1112                 ret = vmbus_recvpacket(channel, packet,
1113                                        ALIGN((sizeof(struct vstor_packet) -
1114                                              vmscsi_size_delta), 8),
1115                                        &bytes_recvd, &request_id);
1116                 if (ret == 0 && bytes_recvd > 0) {
1117
1118                         request = (struct storvsc_cmd_request *)
1119                                         (unsigned long)request_id;
1120
1121                         if ((request == &stor_device->init_request) ||
1122                             (request == &stor_device->reset_request)) {
1123
1124                                 memcpy(&request->vstor_packet, packet,
1125                                        (sizeof(struct vstor_packet) -
1126                                         vmscsi_size_delta));
1127                                 complete(&request->wait_event);
1128                         } else {
1129                                 storvsc_on_receive(stor_device,
1130                                                 (struct vstor_packet *)packet,
1131                                                 request);
1132                         }
1133                 } else {
1134                         break;
1135                 }
1136         } while (1);
1137
1138         return;
1139 }
1140
1141 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
1142                                   bool is_fc)
1143 {
1144         struct vmstorage_channel_properties props;
1145         int ret;
1146
1147         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1148
1149         ret = vmbus_open(device->channel,
1150                          ring_size,
1151                          ring_size,
1152                          (void *)&props,
1153                          sizeof(struct vmstorage_channel_properties),
1154                          storvsc_on_channel_callback, device->channel);
1155
1156         if (ret != 0)
1157                 return ret;
1158
1159         ret = storvsc_channel_init(device, is_fc);
1160
1161         return ret;
1162 }
1163
1164 static int storvsc_dev_remove(struct hv_device *device)
1165 {
1166         struct storvsc_device *stor_device;
1167         unsigned long flags;
1168
1169         stor_device = hv_get_drvdata(device);
1170
1171         spin_lock_irqsave(&device->channel->inbound_lock, flags);
1172         stor_device->destroy = true;
1173         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1174
1175         /*
1176          * At this point, all outbound traffic should be disable. We
1177          * only allow inbound traffic (responses) to proceed so that
1178          * outstanding requests can be completed.
1179          */
1180
1181         storvsc_wait_to_drain(stor_device);
1182
1183         /*
1184          * Since we have already drained, we don't need to busy wait
1185          * as was done in final_release_stor_device()
1186          * Note that we cannot set the ext pointer to NULL until
1187          * we have drained - to drain the outgoing packets, we need to
1188          * allow incoming packets.
1189          */
1190         spin_lock_irqsave(&device->channel->inbound_lock, flags);
1191         hv_set_drvdata(device, NULL);
1192         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1193
1194         /* Close the channel */
1195         vmbus_close(device->channel);
1196
1197         kfree(stor_device);
1198         return 0;
1199 }
1200
1201 static int storvsc_do_io(struct hv_device *device,
1202                          struct storvsc_cmd_request *request)
1203 {
1204         struct storvsc_device *stor_device;
1205         struct vstor_packet *vstor_packet;
1206         struct vmbus_channel *outgoing_channel;
1207         int ret = 0;
1208
1209         vstor_packet = &request->vstor_packet;
1210         stor_device = get_out_stor_device(device);
1211
1212         if (!stor_device)
1213                 return -ENODEV;
1214
1215
1216         request->device  = device;
1217         /*
1218          * Select an an appropriate channel to send the request out.
1219          */
1220
1221         outgoing_channel = vmbus_get_outgoing_channel(device->channel);
1222
1223
1224         vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1225
1226         vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) -
1227                                         vmscsi_size_delta);
1228
1229
1230         vstor_packet->vm_srb.sense_info_length = sense_buffer_size;
1231
1232
1233         vstor_packet->vm_srb.data_transfer_length =
1234         request->payload->range.len;
1235
1236         vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1237
1238         if (request->payload->range.len) {
1239
1240                 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1241                                 request->payload, request->payload_sz,
1242                                 vstor_packet,
1243                                 (sizeof(struct vstor_packet) -
1244                                 vmscsi_size_delta),
1245                                 (unsigned long)request);
1246         } else {
1247                 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1248                                (sizeof(struct vstor_packet) -
1249                                 vmscsi_size_delta),
1250                                (unsigned long)request,
1251                                VM_PKT_DATA_INBAND,
1252                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1253         }
1254
1255         if (ret != 0)
1256                 return ret;
1257
1258         atomic_inc(&stor_device->num_outstanding_req);
1259
1260         return ret;
1261 }
1262
1263 static int storvsc_device_configure(struct scsi_device *sdevice)
1264 {
1265
1266         blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
1267
1268         blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
1269
1270         blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1271
1272         /* Ensure there are no gaps in presented sgls */
1273         blk_queue_virt_boundary(sdevice->request_queue, PAGE_SIZE - 1);
1274
1275         sdevice->no_write_same = 1;
1276
1277         /*
1278          * Add blist flags to permit the reading of the VPD pages even when
1279          * the target may claim SPC-2 compliance. MSFT targets currently
1280          * claim SPC-2 compliance while they implement post SPC-2 features.
1281          * With this patch we can correctly handle WRITE_SAME_16 issues.
1282          */
1283         sdevice->sdev_bflags |= msft_blist_flags;
1284
1285         /*
1286          * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1287          * if the device is a MSFT virtual device.  If the host is
1288          * WIN10 or newer, allow write_same.
1289          */
1290         if (!strncmp(sdevice->vendor, "Msft", 4)) {
1291                 switch (vmstor_proto_version) {
1292                 case VMSTOR_PROTO_VERSION_WIN8:
1293                 case VMSTOR_PROTO_VERSION_WIN8_1:
1294                         sdevice->scsi_level = SCSI_SPC_3;
1295                         break;
1296                 }
1297
1298                 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1299                         sdevice->no_write_same = 0;
1300         }
1301
1302         return 0;
1303 }
1304
1305 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1306                            sector_t capacity, int *info)
1307 {
1308         sector_t nsect = capacity;
1309         sector_t cylinders = nsect;
1310         int heads, sectors_pt;
1311
1312         /*
1313          * We are making up these values; let us keep it simple.
1314          */
1315         heads = 0xff;
1316         sectors_pt = 0x3f;      /* Sectors per track */
1317         sector_div(cylinders, heads * sectors_pt);
1318         if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1319                 cylinders = 0xffff;
1320
1321         info[0] = heads;
1322         info[1] = sectors_pt;
1323         info[2] = (int)cylinders;
1324
1325         return 0;
1326 }
1327
1328 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1329 {
1330         struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1331         struct hv_device *device = host_dev->dev;
1332
1333         struct storvsc_device *stor_device;
1334         struct storvsc_cmd_request *request;
1335         struct vstor_packet *vstor_packet;
1336         int ret, t;
1337
1338
1339         stor_device = get_out_stor_device(device);
1340         if (!stor_device)
1341                 return FAILED;
1342
1343         request = &stor_device->reset_request;
1344         vstor_packet = &request->vstor_packet;
1345
1346         init_completion(&request->wait_event);
1347
1348         vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1349         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1350         vstor_packet->vm_srb.path_id = stor_device->path_id;
1351
1352         ret = vmbus_sendpacket(device->channel, vstor_packet,
1353                                (sizeof(struct vstor_packet) -
1354                                 vmscsi_size_delta),
1355                                (unsigned long)&stor_device->reset_request,
1356                                VM_PKT_DATA_INBAND,
1357                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1358         if (ret != 0)
1359                 return FAILED;
1360
1361         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1362         if (t == 0)
1363                 return TIMEOUT_ERROR;
1364
1365
1366         /*
1367          * At this point, all outstanding requests in the adapter
1368          * should have been flushed out and return to us
1369          * There is a potential race here where the host may be in
1370          * the process of responding when we return from here.
1371          * Just wait for all in-transit packets to be accounted for
1372          * before we return from here.
1373          */
1374         storvsc_wait_to_drain(stor_device);
1375
1376         return SUCCESS;
1377 }
1378
1379 /*
1380  * The host guarantees to respond to each command, although I/O latencies might
1381  * be unbounded on Azure.  Reset the timer unconditionally to give the host a
1382  * chance to perform EH.
1383  */
1384 static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1385 {
1386         return BLK_EH_RESET_TIMER;
1387 }
1388
1389 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1390 {
1391         bool allowed = true;
1392         u8 scsi_op = scmnd->cmnd[0];
1393
1394         switch (scsi_op) {
1395         /* the host does not handle WRITE_SAME, log accident usage */
1396         case WRITE_SAME:
1397         /*
1398          * smartd sends this command and the host does not handle
1399          * this. So, don't send it.
1400          */
1401         case SET_WINDOW:
1402                 scmnd->result = ILLEGAL_REQUEST << 16;
1403                 allowed = false;
1404                 break;
1405         default:
1406                 break;
1407         }
1408         return allowed;
1409 }
1410
1411 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1412 {
1413         int ret;
1414         struct hv_host_device *host_dev = shost_priv(host);
1415         struct hv_device *dev = host_dev->dev;
1416         struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1417         int i;
1418         struct scatterlist *sgl;
1419         unsigned int sg_count = 0;
1420         struct vmscsi_request *vm_srb;
1421         struct scatterlist *cur_sgl;
1422         struct vmbus_packet_mpb_array  *payload;
1423         u32 payload_sz;
1424         u32 length;
1425
1426         if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1427                 /*
1428                  * On legacy hosts filter unimplemented commands.
1429                  * Future hosts are expected to correctly handle
1430                  * unsupported commands. Furthermore, it is
1431                  * possible that some of the currently
1432                  * unsupported commands maybe supported in
1433                  * future versions of the host.
1434                  */
1435                 if (!storvsc_scsi_cmd_ok(scmnd)) {
1436                         scmnd->scsi_done(scmnd);
1437                         return 0;
1438                 }
1439         }
1440
1441         /* Setup the cmd request */
1442         cmd_request->cmd = scmnd;
1443
1444         vm_srb = &cmd_request->vstor_packet.vm_srb;
1445         vm_srb->win8_extension.time_out_value = 60;
1446
1447         vm_srb->win8_extension.srb_flags |=
1448                 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1449
1450         /* Build the SRB */
1451         switch (scmnd->sc_data_direction) {
1452         case DMA_TO_DEVICE:
1453                 vm_srb->data_in = WRITE_TYPE;
1454                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_OUT;
1455                 break;
1456         case DMA_FROM_DEVICE:
1457                 vm_srb->data_in = READ_TYPE;
1458                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_IN;
1459                 break;
1460         case DMA_NONE:
1461                 vm_srb->data_in = UNKNOWN_TYPE;
1462                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1463                 break;
1464         default:
1465                 /*
1466                  * This is DMA_BIDIRECTIONAL or something else we are never
1467                  * supposed to see here.
1468                  */
1469                 WARN(1, "Unexpected data direction: %d\n",
1470                      scmnd->sc_data_direction);
1471                 return -EINVAL;
1472         }
1473
1474
1475         vm_srb->port_number = host_dev->port;
1476         vm_srb->path_id = scmnd->device->channel;
1477         vm_srb->target_id = scmnd->device->id;
1478         vm_srb->lun = scmnd->device->lun;
1479
1480         vm_srb->cdb_length = scmnd->cmd_len;
1481
1482         memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1483
1484         sgl = (struct scatterlist *)scsi_sglist(scmnd);
1485         sg_count = scsi_sg_count(scmnd);
1486
1487         length = scsi_bufflen(scmnd);
1488         payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1489         payload_sz = sizeof(cmd_request->mpb);
1490
1491         if (sg_count) {
1492                 if (sg_count > MAX_PAGE_BUFFER_COUNT) {
1493
1494                         payload_sz = (sg_count * sizeof(void *) +
1495                                       sizeof(struct vmbus_packet_mpb_array));
1496                         payload = kmalloc(payload_sz, GFP_ATOMIC);
1497                         if (!payload)
1498                                 return SCSI_MLQUEUE_DEVICE_BUSY;
1499                 }
1500
1501                 payload->range.len = length;
1502                 payload->range.offset = sgl[0].offset;
1503
1504                 cur_sgl = sgl;
1505                 for (i = 0; i < sg_count; i++) {
1506                         payload->range.pfn_array[i] =
1507                                 page_to_pfn(sg_page((cur_sgl)));
1508                         cur_sgl = sg_next(cur_sgl);
1509                 }
1510
1511         } else if (scsi_sglist(scmnd)) {
1512                 payload->range.len = length;
1513                 payload->range.offset =
1514                         virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
1515                 payload->range.pfn_array[0] =
1516                         virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
1517         }
1518
1519         cmd_request->payload = payload;
1520         cmd_request->payload_sz = payload_sz;
1521
1522         /* Invokes the vsc to start an IO */
1523         ret = storvsc_do_io(dev, cmd_request);
1524
1525         if (ret == -EAGAIN) {
1526                 /* no more space */
1527                 return SCSI_MLQUEUE_DEVICE_BUSY;
1528         }
1529
1530         return 0;
1531 }
1532
1533 static struct scsi_host_template scsi_driver = {
1534         .module =               THIS_MODULE,
1535         .name =                 "storvsc_host_t",
1536         .cmd_size =             sizeof(struct storvsc_cmd_request),
1537         .bios_param =           storvsc_get_chs,
1538         .queuecommand =         storvsc_queuecommand,
1539         .eh_host_reset_handler =        storvsc_host_reset_handler,
1540         .proc_name =            "storvsc_host",
1541         .eh_timed_out =         storvsc_eh_timed_out,
1542         .slave_configure =      storvsc_device_configure,
1543         .cmd_per_lun =          255,
1544         .this_id =              -1,
1545         .use_clustering =       ENABLE_CLUSTERING,
1546         /* Make sure we dont get a sg segment crosses a page boundary */
1547         .dma_boundary =         PAGE_SIZE-1,
1548         .no_write_same =        1,
1549 };
1550
1551 enum {
1552         SCSI_GUID,
1553         IDE_GUID,
1554         SFC_GUID,
1555 };
1556
1557 static const struct hv_vmbus_device_id id_table[] = {
1558         /* SCSI guid */
1559         { HV_SCSI_GUID,
1560           .driver_data = SCSI_GUID
1561         },
1562         /* IDE guid */
1563         { HV_IDE_GUID,
1564           .driver_data = IDE_GUID
1565         },
1566         /* Fibre Channel GUID */
1567         {
1568           HV_SYNTHFC_GUID,
1569           .driver_data = SFC_GUID
1570         },
1571         { },
1572 };
1573
1574 MODULE_DEVICE_TABLE(vmbus, id_table);
1575
1576 static int storvsc_probe(struct hv_device *device,
1577                         const struct hv_vmbus_device_id *dev_id)
1578 {
1579         int ret;
1580         int num_cpus = num_online_cpus();
1581         struct Scsi_Host *host;
1582         struct hv_host_device *host_dev;
1583         bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1584         bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
1585         int target = 0;
1586         struct storvsc_device *stor_device;
1587         int max_luns_per_target;
1588         int max_targets;
1589         int max_channels;
1590         int max_sub_channels = 0;
1591
1592         /*
1593          * Based on the windows host we are running on,
1594          * set state to properly communicate with the host.
1595          */
1596
1597         if (vmbus_proto_version < VERSION_WIN8) {
1598                 max_luns_per_target = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1599                 max_targets = STORVSC_IDE_MAX_TARGETS;
1600                 max_channels = STORVSC_IDE_MAX_CHANNELS;
1601         } else {
1602                 max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET;
1603                 max_targets = STORVSC_MAX_TARGETS;
1604                 max_channels = STORVSC_MAX_CHANNELS;
1605                 /*
1606                  * On Windows8 and above, we support sub-channels for storage.
1607                  * The number of sub-channels offerred is based on the number of
1608                  * VCPUs in the guest.
1609                  */
1610                 max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel);
1611         }
1612
1613         scsi_driver.can_queue = (max_outstanding_req_per_channel *
1614                                  (max_sub_channels + 1));
1615
1616         host = scsi_host_alloc(&scsi_driver,
1617                                sizeof(struct hv_host_device));
1618         if (!host)
1619                 return -ENOMEM;
1620
1621         host_dev = shost_priv(host);
1622         memset(host_dev, 0, sizeof(struct hv_host_device));
1623
1624         host_dev->port = host->host_no;
1625         host_dev->dev = device;
1626
1627
1628         stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
1629         if (!stor_device) {
1630                 ret = -ENOMEM;
1631                 goto err_out0;
1632         }
1633
1634         stor_device->destroy = false;
1635         stor_device->open_sub_channel = false;
1636         init_waitqueue_head(&stor_device->waiting_to_drain);
1637         stor_device->device = device;
1638         stor_device->host = host;
1639         hv_set_drvdata(device, stor_device);
1640
1641         stor_device->port_number = host->host_no;
1642         ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size, is_fc);
1643         if (ret)
1644                 goto err_out1;
1645
1646         host_dev->path = stor_device->path_id;
1647         host_dev->target = stor_device->target_id;
1648
1649         switch (dev_id->driver_data) {
1650         case SFC_GUID:
1651                 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
1652                 host->max_id = STORVSC_FC_MAX_TARGETS;
1653                 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
1654 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1655                 host->transportt = fc_transport_template;
1656 #endif
1657                 break;
1658
1659         case SCSI_GUID:
1660                 host->max_lun = max_luns_per_target;
1661                 host->max_id = max_targets;
1662                 host->max_channel = max_channels - 1;
1663                 break;
1664
1665         default:
1666                 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1667                 host->max_id = STORVSC_IDE_MAX_TARGETS;
1668                 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
1669                 break;
1670         }
1671         /* max cmd length */
1672         host->max_cmd_len = STORVSC_MAX_CMD_LEN;
1673
1674         /*
1675          * set the table size based on the info we got
1676          * from the host.
1677          */
1678         host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
1679
1680         /* Register the HBA and start the scsi bus scan */
1681         ret = scsi_add_host(host, &device->device);
1682         if (ret != 0)
1683                 goto err_out2;
1684
1685         if (!dev_is_ide) {
1686                 scsi_scan_host(host);
1687         } else {
1688                 target = (device->dev_instance.b[5] << 8 |
1689                          device->dev_instance.b[4]);
1690                 ret = scsi_add_device(host, 0, target, 0);
1691                 if (ret) {
1692                         scsi_remove_host(host);
1693                         goto err_out2;
1694                 }
1695         }
1696 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1697         if (host->transportt == fc_transport_template) {
1698                 fc_host_node_name(host) = stor_device->node_name;
1699                 fc_host_port_name(host) = stor_device->port_name;
1700         }
1701 #endif
1702         return 0;
1703
1704 err_out2:
1705         /*
1706          * Once we have connected with the host, we would need to
1707          * to invoke storvsc_dev_remove() to rollback this state and
1708          * this call also frees up the stor_device; hence the jump around
1709          * err_out1 label.
1710          */
1711         storvsc_dev_remove(device);
1712         goto err_out0;
1713
1714 err_out1:
1715         kfree(stor_device);
1716
1717 err_out0:
1718         scsi_host_put(host);
1719         return ret;
1720 }
1721
1722 static int storvsc_remove(struct hv_device *dev)
1723 {
1724         struct storvsc_device *stor_device = hv_get_drvdata(dev);
1725         struct Scsi_Host *host = stor_device->host;
1726
1727 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1728         if (host->transportt == fc_transport_template)
1729                 fc_remove_host(host);
1730 #endif
1731         scsi_remove_host(host);
1732         storvsc_dev_remove(dev);
1733         scsi_host_put(host);
1734
1735         return 0;
1736 }
1737
1738 static struct hv_driver storvsc_drv = {
1739         .name = KBUILD_MODNAME,
1740         .id_table = id_table,
1741         .probe = storvsc_probe,
1742         .remove = storvsc_remove,
1743 };
1744
1745 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1746 static struct fc_function_template fc_transport_functions = {
1747         .show_host_node_name = 1,
1748         .show_host_port_name = 1,
1749 };
1750 #endif
1751
1752 static int __init storvsc_drv_init(void)
1753 {
1754         int ret;
1755
1756         /*
1757          * Divide the ring buffer data size (which is 1 page less
1758          * than the ring buffer size since that page is reserved for
1759          * the ring buffer indices) by the max request size (which is
1760          * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
1761          */
1762         max_outstanding_req_per_channel =
1763                 ((storvsc_ringbuffer_size - PAGE_SIZE) /
1764                 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
1765                 sizeof(struct vstor_packet) + sizeof(u64) -
1766                 vmscsi_size_delta,
1767                 sizeof(u64)));
1768
1769 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1770         fc_transport_template = fc_attach_transport(&fc_transport_functions);
1771         if (!fc_transport_template)
1772                 return -ENODEV;
1773 #endif
1774
1775         ret = vmbus_driver_register(&storvsc_drv);
1776
1777 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1778         if (ret)
1779                 fc_release_transport(fc_transport_template);
1780 #endif
1781
1782         return ret;
1783 }
1784
1785 static void __exit storvsc_drv_exit(void)
1786 {
1787         vmbus_driver_unregister(&storvsc_drv);
1788 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1789         fc_release_transport(fc_transport_template);
1790 #endif
1791 }
1792
1793 MODULE_LICENSE("GPL");
1794 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
1795 module_init(storvsc_drv_init);
1796 module_exit(storvsc_drv_exit);