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 #include <scsi/scsi_transport.h>
  46
  47 /*
  48  * All wire protocol details (storage protocol between the guest and the host)
  49  * are consolidated here.
  50  *
  51  * Begin protocol definitions.
  52  */
  53
  54 /*
  55  * Version history:
  56  * V1 Beta: 0.1
  57  * V1 RC < 2008/1/31: 1.0
  58  * V1 RC > 2008/1/31:  2.0
  59  * Win7: 4.2
  60  * Win8: 5.1
  61  * Win8.1: 6.0
  62  * Win10: 6.2
  63  */
  64
  65 #define VMSTOR_PROTO_VERSION(MAJOR_, MINOR_)    ((((MAJOR_) & 0xff) << 8) | \
  66                                                 (((MINOR_) & 0xff)))
  67
  68 #define VMSTOR_PROTO_VERSION_WIN6       VMSTOR_PROTO_VERSION(2, 0)
  69 #define VMSTOR_PROTO_VERSION_WIN7       VMSTOR_PROTO_VERSION(4, 2)
  70 #define VMSTOR_PROTO_VERSION_WIN8       VMSTOR_PROTO_VERSION(5, 1)
  71 #define VMSTOR_PROTO_VERSION_WIN8_1     VMSTOR_PROTO_VERSION(6, 0)
  72 #define VMSTOR_PROTO_VERSION_WIN10      VMSTOR_PROTO_VERSION(6, 2)
  73
  74 /*  Packet structure describing virtual storage requests. */
  75 enum vstor_packet_operation {
  76         VSTOR_OPERATION_COMPLETE_IO             = 1,
  77         VSTOR_OPERATION_REMOVE_DEVICE           = 2,
  78         VSTOR_OPERATION_EXECUTE_SRB             = 3,
  79         VSTOR_OPERATION_RESET_LUN               = 4,
  80         VSTOR_OPERATION_RESET_ADAPTER           = 5,
  81         VSTOR_OPERATION_RESET_BUS               = 6,
  82         VSTOR_OPERATION_BEGIN_INITIALIZATION    = 7,
  83         VSTOR_OPERATION_END_INITIALIZATION      = 8,
  84         VSTOR_OPERATION_QUERY_PROTOCOL_VERSION  = 9,
  85         VSTOR_OPERATION_QUERY_PROPERTIES        = 10,
  86         VSTOR_OPERATION_ENUMERATE_BUS           = 11,
  87         VSTOR_OPERATION_FCHBA_DATA              = 12,
  88         VSTOR_OPERATION_CREATE_SUB_CHANNELS     = 13,
  89         VSTOR_OPERATION_MAXIMUM                 = 13
  90 };
  91
  92 /*
  93  * WWN packet for Fibre Channel HBA
  94  */
  95
  96 struct hv_fc_wwn_packet {
  97         u8      primary_active;
  98         u8      reserved1[3];
  99         u8      primary_port_wwn[8];
 100         u8      primary_node_wwn[8];
 101         u8      secondary_port_wwn[8];
 102         u8      secondary_node_wwn[8];
 103 };
 104
 105
 106
 107 /*
 108  * SRB Flag Bits
 109  */
 110
 111 #define SRB_FLAGS_QUEUE_ACTION_ENABLE           0x00000002
 112 #define SRB_FLAGS_DISABLE_DISCONNECT            0x00000004
 113 #define SRB_FLAGS_DISABLE_SYNCH_TRANSFER        0x00000008
 114 #define SRB_FLAGS_BYPASS_FROZEN_QUEUE           0x00000010
 115 #define SRB_FLAGS_DISABLE_AUTOSENSE             0x00000020
 116 #define SRB_FLAGS_DATA_IN                       0x00000040
 117 #define SRB_FLAGS_DATA_OUT                      0x00000080
 118 #define SRB_FLAGS_NO_DATA_TRANSFER              0x00000000
 119 #define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT)
 120 #define SRB_FLAGS_NO_QUEUE_FREEZE               0x00000100
 121 #define SRB_FLAGS_ADAPTER_CACHE_ENABLE          0x00000200
 122 #define SRB_FLAGS_FREE_SENSE_BUFFER             0x00000400
 123
 124 /*
 125  * This flag indicates the request is part of the workflow for processing a D3.
 126  */
 127 #define SRB_FLAGS_D3_PROCESSING                 0x00000800
 128 #define SRB_FLAGS_IS_ACTIVE                     0x00010000
 129 #define SRB_FLAGS_ALLOCATED_FROM_ZONE           0x00020000
 130 #define SRB_FLAGS_SGLIST_FROM_POOL              0x00040000
 131 #define SRB_FLAGS_BYPASS_LOCKED_QUEUE           0x00080000
 132 #define SRB_FLAGS_NO_KEEP_AWAKE                 0x00100000
 133 #define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE        0x00200000
 134 #define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT      0x00400000
 135 #define SRB_FLAGS_DONT_START_NEXT_PACKET        0x00800000
 136 #define SRB_FLAGS_PORT_DRIVER_RESERVED          0x0F000000
 137 #define SRB_FLAGS_CLASS_DRIVER_RESERVED         0xF0000000
 138
 139 #define SP_UNTAGGED                     ((unsigned char) ~0)
 140 #define SRB_SIMPLE_TAG_REQUEST          0x20
 141
 142 /*
 143  * Platform neutral description of a scsi request -
 144  * this remains the same across the write regardless of 32/64 bit
 145  * note: it's patterned off the SCSI_PASS_THROUGH structure
 146  */
 147 #define STORVSC_MAX_CMD_LEN                     0x10
 148
 149 #define POST_WIN7_STORVSC_SENSE_BUFFER_SIZE     0x14
 150 #define PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE      0x12
 151
 152 #define STORVSC_SENSE_BUFFER_SIZE               0x14
 153 #define STORVSC_MAX_BUF_LEN_WITH_PADDING        0x14
 154
 155 /*
 156  * Sense buffer size changed in win8; have a run-time
 157  * variable to track the size we should use.  This value will
 158  * likely change during protocol negotiation but it is valid
 159  * to start by assuming pre-Win8.
 160  */
 161 static int sense_buffer_size = PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE;
 162
 163 /*
 164  * The storage protocol version is determined during the
 165  * initial exchange with the host.  It will indicate which
 166  * storage functionality is available in the host.
 167 */
 168 static int vmstor_proto_version;
 169
 170 #define STORVSC_LOGGING_NONE    0
 171 #define STORVSC_LOGGING_ERROR   1
 172 #define STORVSC_LOGGING_WARN    2
 173
 174 static int logging_level = STORVSC_LOGGING_ERROR;
 175 module_param(logging_level, int, S_IRUGO|S_IWUSR);
 176 MODULE_PARM_DESC(logging_level,
 177         "Logging level, 0 - None, 1 - Error (default), 2 - Warning.");
 178
 179 static inline bool do_logging(int level)
 180 {
 181         return logging_level >= level;
 182 }
 183
 184 #define storvsc_log(dev, level, fmt, ...)                       \
 185 do {                                                            \
 186         if (do_logging(level))                                  \
 187                 dev_warn(&(dev)->device, fmt, ##__VA_ARGS__);   \
 188 } while (0)
 189
 190 struct vmscsi_win8_extension {
 191         /*
 192          * The following were added in Windows 8
 193          */
 194         u16 reserve;
 195         u8  queue_tag;
 196         u8  queue_action;
 197         u32 srb_flags;
 198         u32 time_out_value;
 199         u32 queue_sort_ey;
 200 } __packed;
 201
 202 struct vmscsi_request {
 203         u16 length;
 204         u8 srb_status;
 205         u8 scsi_status;
 206
 207         u8  port_number;
 208         u8  path_id;
 209         u8  target_id;
 210         u8  lun;
 211
 212         u8  cdb_length;
 213         u8  sense_info_length;
 214         u8  data_in;
 215         u8  reserved;
 216
 217         u32 data_transfer_length;
 218
 219         union {
 220                 u8 cdb[STORVSC_MAX_CMD_LEN];
 221                 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
 222                 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
 223         };
 224         /*
 225          * The following was added in win8.
 226          */
 227         struct vmscsi_win8_extension win8_extension;
 228
 229 } __attribute((packed));
 230
 231
 232 /*
 233  * The size of the vmscsi_request has changed in win8. The
 234  * additional size is because of new elements added to the
 235  * structure. These elements are valid only when we are talking
 236  * to a win8 host.
 237  * Track the correction to size we need to apply. This value
 238  * will likely change during protocol negotiation but it is
 239  * valid to start by assuming pre-Win8.
 240  */
 241 static int vmscsi_size_delta = sizeof(struct vmscsi_win8_extension);
 242
 243 /*
 244  * The list of storage protocols in order of preference.
 245  */
 246 struct vmstor_protocol {
 247         int protocol_version;
 248         int sense_buffer_size;
 249         int vmscsi_size_delta;
 250 };
 251
 252
 253 static const struct vmstor_protocol vmstor_protocols[] = {
 254         {
 255                 VMSTOR_PROTO_VERSION_WIN10,
 256                 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
 257                 0
 258         },
 259         {
 260                 VMSTOR_PROTO_VERSION_WIN8_1,
 261                 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
 262                 0
 263         },
 264         {
 265                 VMSTOR_PROTO_VERSION_WIN8,
 266                 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
 267                 0
 268         },
 269         {
 270                 VMSTOR_PROTO_VERSION_WIN7,
 271                 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
 272                 sizeof(struct vmscsi_win8_extension),
 273         },
 274         {
 275                 VMSTOR_PROTO_VERSION_WIN6,
 276                 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
 277                 sizeof(struct vmscsi_win8_extension),
 278         }
 279 };
 280
 281
 282 /*
 283  * This structure is sent during the intialization phase to get the different
 284  * properties of the channel.
 285  */
 286
 287 #define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL          0x1
 288
 289 struct vmstorage_channel_properties {
 290         u32 reserved;
 291         u16 max_channel_cnt;
 292         u16 reserved1;
 293
 294         u32 flags;
 295         u32   max_transfer_bytes;
 296
 297         u64  reserved2;
 298 } __packed;
 299
 300 /*  This structure is sent during the storage protocol negotiations. */
 301 struct vmstorage_protocol_version {
 302         /* Major (MSW) and minor (LSW) version numbers. */
 303         u16 major_minor;
 304
 305         /*
 306          * Revision number is auto-incremented whenever this file is changed
 307          * (See FILL_VMSTOR_REVISION macro above).  Mismatch does not
 308          * definitely indicate incompatibility--but it does indicate mismatched
 309          * builds.
 310          * This is only used on the windows side. Just set it to 0.
 311          */
 312         u16 revision;
 313 } __packed;
 314
 315 /* Channel Property Flags */
 316 #define STORAGE_CHANNEL_REMOVABLE_FLAG          0x1
 317 #define STORAGE_CHANNEL_EMULATED_IDE_FLAG       0x2
 318
 319 struct vstor_packet {
 320         /* Requested operation type */
 321         enum vstor_packet_operation operation;
 322
 323         /*  Flags - see below for values */
 324         u32 flags;
 325
 326         /* Status of the request returned from the server side. */
 327         u32 status;
 328
 329         /* Data payload area */
 330         union {
 331                 /*
 332                  * Structure used to forward SCSI commands from the
 333                  * client to the server.
 334                  */
 335                 struct vmscsi_request vm_srb;
 336
 337                 /* Structure used to query channel properties. */
 338                 struct vmstorage_channel_properties storage_channel_properties;
 339
 340                 /* Used during version negotiations. */
 341                 struct vmstorage_protocol_version version;
 342
 343                 /* Fibre channel address packet */
 344                 struct hv_fc_wwn_packet wwn_packet;
 345
 346                 /* Number of sub-channels to create */
 347                 u16 sub_channel_count;
 348
 349                 /* This will be the maximum of the union members */
 350                 u8  buffer[0x34];
 351         };
 352 } __packed;
 353
 354 /*
 355  * Packet Flags:
 356  *
 357  * This flag indicates that the server should send back a completion for this
 358  * packet.
 359  */
 360
 361 #define REQUEST_COMPLETION_FLAG 0x1
 362
 363 /* Matches Windows-end */
 364 enum storvsc_request_type {
 365         WRITE_TYPE = 0,
 366         READ_TYPE,
 367         UNKNOWN_TYPE,
 368 };
 369
 370 /*
 371  * SRB status codes and masks; a subset of the codes used here.
 372  */
 373
 374 #define SRB_STATUS_AUTOSENSE_VALID      0x80
 375 #define SRB_STATUS_QUEUE_FROZEN         0x40
 376 #define SRB_STATUS_INVALID_LUN  0x20
 377 #define SRB_STATUS_SUCCESS      0x01
 378 #define SRB_STATUS_ABORTED      0x02
 379 #define SRB_STATUS_ERROR        0x04
 380 #define SRB_STATUS_DATA_OVERRUN 0x12
 381
 382 #define SRB_STATUS(status) \
 383         (status & ~(SRB_STATUS_AUTOSENSE_VALID | SRB_STATUS_QUEUE_FROZEN))
 384 /*
 385  * This is the end of Protocol specific defines.
 386  */
 387
 388 static int storvsc_ringbuffer_size = (256 * PAGE_SIZE);
 389 static u32 max_outstanding_req_per_channel;
 390
 391 static int storvsc_vcpus_per_sub_channel = 4;
 392
 393 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
 394 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
 395
 396 module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
 397 MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
 398 /*
 399  * Timeout in seconds for all devices managed by this driver.
 400  */
 401 static int storvsc_timeout = 180;
 402
 403 static int msft_blist_flags = BLIST_TRY_VPD_PAGES;
 404
 405 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
 406 static struct scsi_transport_template *fc_transport_template;
 407 #endif
 408
 409 static void storvsc_on_channel_callback(void *context);
 410
 411 #define STORVSC_MAX_LUNS_PER_TARGET                     255
 412 #define STORVSC_MAX_TARGETS                             2
 413 #define STORVSC_MAX_CHANNELS                            8
 414
 415 #define STORVSC_FC_MAX_LUNS_PER_TARGET                  255
 416 #define STORVSC_FC_MAX_TARGETS                          128
 417 #define STORVSC_FC_MAX_CHANNELS                         8
 418
 419 #define STORVSC_IDE_MAX_LUNS_PER_TARGET                 64
 420 #define STORVSC_IDE_MAX_TARGETS                         1
 421 #define STORVSC_IDE_MAX_CHANNELS                        1
 422
 423 struct storvsc_cmd_request {
 424         struct scsi_cmnd *cmd;
 425
 426         struct hv_device *device;
 427
 428         /* Synchronize the request/response if needed */
 429         struct completion wait_event;
 430
 431         struct vmbus_channel_packet_multipage_buffer mpb;
 432         struct vmbus_packet_mpb_array *payload;
 433         u32 payload_sz;
 434
 435         struct vstor_packet vstor_packet;
 436 };
 437
 438
 439 /* A storvsc device is a device object that contains a vmbus channel */
 440 struct storvsc_device {
 441         struct hv_device *device;
 442
 443         bool     destroy;
 444         bool     drain_notify;
 445         bool     open_sub_channel;
 446         atomic_t num_outstanding_req;
 447         struct Scsi_Host *host;
 448
 449         wait_queue_head_t waiting_to_drain;
 450
 451         /*
 452          * Each unique Port/Path/Target represents 1 channel ie scsi
 453          * controller. In reality, the pathid, targetid is always 0
 454          * and the port is set by us
 455          */
 456         unsigned int port_number;
 457         unsigned char path_id;
 458         unsigned char target_id;
 459
 460         /*
 461          * Max I/O, the device can support.
 462          */
 463         u32   max_transfer_bytes;
 464         /*
 465          * Number of sub-channels we will open.
 466          */
 467         u16 num_sc;
 468         struct vmbus_channel **stor_chns;
 469         /*
 470          * Mask of CPUs bound to subchannels.
 471          */
 472         struct cpumask alloced_cpus;
 473         /* Used for vsc/vsp channel reset process */
 474         struct storvsc_cmd_request init_request;
 475         struct storvsc_cmd_request reset_request;
 476         /*
 477          * Currently active port and node names for FC devices.
 478          */
 479         u64 node_name;
 480         u64 port_name;
 481 };
 482
 483 struct hv_host_device {
 484         struct hv_device *dev;
 485         unsigned int port;
 486         unsigned char path;
 487         unsigned char target;
 488 };
 489
 490 struct storvsc_scan_work {
 491         struct work_struct work;
 492         struct Scsi_Host *host;
 493         u8 lun;
 494         u8 tgt_id;
 495 };
 496
 497 static void storvsc_device_scan(struct work_struct *work)
 498 {
 499         struct storvsc_scan_work *wrk;
 500         struct scsi_device *sdev;
 501
 502         wrk = container_of(work, struct storvsc_scan_work, work);
 503
 504         sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
 505         if (!sdev)
 506                 goto done;
 507         scsi_rescan_device(&sdev->sdev_gendev);
 508         scsi_device_put(sdev);
 509
 510 done:
 511         kfree(wrk);
 512 }
 513
 514 static void storvsc_host_scan(struct work_struct *work)
 515 {
 516         struct storvsc_scan_work *wrk;
 517         struct Scsi_Host *host;
 518         struct scsi_device *sdev;
 519
 520         wrk = container_of(work, struct storvsc_scan_work, work);
 521         host = wrk->host;
 522
 523         /*
 524          * Before scanning the host, first check to see if any of the
 525          * currrently known devices have been hot removed. We issue a
 526          * "unit ready" command against all currently known devices.
 527          * This I/O will result in an error for devices that have been
 528          * removed. As part of handling the I/O error, we remove the device.
 529          *
 530          * When a LUN is added or removed, the host sends us a signal to
 531          * scan the host. Thus we are forced to discover the LUNs that
 532          * may have been removed this way.
 533          */
 534         mutex_lock(&host->scan_mutex);
 535         shost_for_each_device(sdev, host)
 536                 scsi_test_unit_ready(sdev, 1, 1, NULL);
 537         mutex_unlock(&host->scan_mutex);
 538         /*
 539          * Now scan the host to discover LUNs that may have been added.
 540          */
 541         scsi_scan_host(host);
 542
 543         kfree(wrk);
 544 }
 545
 546 static void storvsc_remove_lun(struct work_struct *work)
 547 {
 548         struct storvsc_scan_work *wrk;
 549         struct scsi_device *sdev;
 550
 551         wrk = container_of(work, struct storvsc_scan_work, work);
 552         if (!scsi_host_get(wrk->host))
 553                 goto done;
 554
 555         sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
 556
 557         if (sdev) {
 558                 scsi_remove_device(sdev);
 559                 scsi_device_put(sdev);
 560         }
 561         scsi_host_put(wrk->host);
 562
 563 done:
 564         kfree(wrk);
 565 }
 566
 567
 568 /*
 569  * We can get incoming messages from the host that are not in response to
 570  * messages that we have sent out. An example of this would be messages
 571  * received by the guest to notify dynamic addition/removal of LUNs. To
 572  * deal with potential race conditions where the driver may be in the
 573  * midst of being unloaded when we might receive an unsolicited message
 574  * from the host, we have implemented a mechanism to gurantee sequential
 575  * consistency:
 576  *
 577  * 1) Once the device is marked as being destroyed, we will fail all
 578  *    outgoing messages.
 579  * 2) We permit incoming messages when the device is being destroyed,
 580  *    only to properly account for messages already sent out.
 581  */
 582
 583 static inline struct storvsc_device *get_out_stor_device(
 584                                         struct hv_device *device)
 585 {
 586         struct storvsc_device *stor_device;
 587
 588         stor_device = hv_get_drvdata(device);
 589
 590         if (stor_device && stor_device->destroy)
 591                 stor_device = NULL;
 592
 593         return stor_device;
 594 }
 595
 596
 597 static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
 598 {
 599         dev->drain_notify = true;
 600         wait_event(dev->waiting_to_drain,
 601                    atomic_read(&dev->num_outstanding_req) == 0);
 602         dev->drain_notify = false;
 603 }
 604
 605 static inline struct storvsc_device *get_in_stor_device(
 606                                         struct hv_device *device)
 607 {
 608         struct storvsc_device *stor_device;
 609
 610         stor_device = hv_get_drvdata(device);
 611
 612         if (!stor_device)
 613                 goto get_in_err;
 614
 615         /*
 616          * If the device is being destroyed; allow incoming
 617          * traffic only to cleanup outstanding requests.
 618          */
 619
 620         if (stor_device->destroy  &&
 621                 (atomic_read(&stor_device->num_outstanding_req) == 0))
 622                 stor_device = NULL;
 623
 624 get_in_err:
 625         return stor_device;
 626
 627 }
 628
 629 static void handle_sc_creation(struct vmbus_channel *new_sc)
 630 {
 631         struct hv_device *device = new_sc->primary_channel->device_obj;
 632         struct storvsc_device *stor_device;
 633         struct vmstorage_channel_properties props;
 634
 635         stor_device = get_out_stor_device(device);
 636         if (!stor_device)
 637                 return;
 638
 639         if (stor_device->open_sub_channel == false)
 640                 return;
 641
 642         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
 643
 644         vmbus_open(new_sc,
 645                    storvsc_ringbuffer_size,
 646                    storvsc_ringbuffer_size,
 647                    (void *)&props,
 648                    sizeof(struct vmstorage_channel_properties),
 649                    storvsc_on_channel_callback, new_sc);
 650
 651         if (new_sc->state == CHANNEL_OPENED_STATE) {
 652                 stor_device->stor_chns[new_sc->target_cpu] = new_sc;
 653                 cpumask_set_cpu(new_sc->target_cpu, &stor_device->alloced_cpus);
 654         }
 655 }
 656
 657 static void  handle_multichannel_storage(struct hv_device *device, int max_chns)
 658 {
 659         struct storvsc_device *stor_device;
 660         int num_cpus = num_online_cpus();
 661         int num_sc;
 662         struct storvsc_cmd_request *request;
 663         struct vstor_packet *vstor_packet;
 664         int ret, t;
 665
 666         num_sc = ((max_chns > num_cpus) ? num_cpus : max_chns);
 667         stor_device = get_out_stor_device(device);
 668         if (!stor_device)
 669                 return;
 670
 671         stor_device->num_sc = num_sc;
 672         request = &stor_device->init_request;
 673         vstor_packet = &request->vstor_packet;
 674
 675         stor_device->open_sub_channel = true;
 676         /*
 677          * Establish a handler for dealing with subchannels.
 678          */
 679         vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
 680
 681         /*
 682          * Check to see if sub-channels have already been created. This
 683          * can happen when this driver is re-loaded after unloading.
 684          */
 685
 686         if (vmbus_are_subchannels_present(device->channel))
 687                 return;
 688
 689         stor_device->open_sub_channel = false;
 690         /*
 691          * Request the host to create sub-channels.
 692          */
 693         memset(request, 0, sizeof(struct storvsc_cmd_request));
 694         init_completion(&request->wait_event);
 695         vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
 696         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 697         vstor_packet->sub_channel_count = num_sc;
 698
 699         ret = vmbus_sendpacket(device->channel, vstor_packet,
 700                                (sizeof(struct vstor_packet) -
 701                                vmscsi_size_delta),
 702                                (unsigned long)request,
 703                                VM_PKT_DATA_INBAND,
 704                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 705
 706         if (ret != 0)
 707                 return;
 708
 709         t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
 710         if (t == 0)
 711                 return;
 712
 713         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 714             vstor_packet->status != 0)
 715                 return;
 716
 717         /*
 718          * Now that we created the sub-channels, invoke the check; this
 719          * may trigger the callback.
 720          */
 721         stor_device->open_sub_channel = true;
 722         vmbus_are_subchannels_present(device->channel);
 723 }
 724
 725 static void cache_wwn(struct storvsc_device *stor_device,
 726                       struct vstor_packet *vstor_packet)
 727 {
 728         /*
 729          * Cache the currently active port and node ww names.
 730          */
 731         if (vstor_packet->wwn_packet.primary_active) {
 732                 stor_device->node_name =
 733                         wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
 734                 stor_device->port_name =
 735                         wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
 736         } else {
 737                 stor_device->node_name =
 738                         wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
 739                 stor_device->port_name =
 740                         wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
 741         }
 742 }
 743
 744
 745 static int storvsc_execute_vstor_op(struct hv_device *device,
 746                                     struct storvsc_cmd_request *request,
 747                                     bool status_check)
 748 {
 749         struct vstor_packet *vstor_packet;
 750         int ret, t;
 751
 752         vstor_packet = &request->vstor_packet;
 753
 754         init_completion(&request->wait_event);
 755         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 756
 757         ret = vmbus_sendpacket(device->channel, vstor_packet,
 758                                (sizeof(struct vstor_packet) -
 759                                vmscsi_size_delta),
 760                                (unsigned long)request,
 761                                VM_PKT_DATA_INBAND,
 762                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 763         if (ret != 0)
 764                 return ret;
 765
 766         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
 767         if (t == 0)
 768                 return -ETIMEDOUT;
 769
 770         if (!status_check)
 771                 return ret;
 772
 773         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 774             vstor_packet->status != 0)
 775                 return -EINVAL;
 776
 777         return ret;
 778 }
 779
 780 static int storvsc_channel_init(struct hv_device *device, bool is_fc)
 781 {
 782         struct storvsc_device *stor_device;
 783         struct storvsc_cmd_request *request;
 784         struct vstor_packet *vstor_packet;
 785         int ret, i;
 786         int max_chns;
 787         bool process_sub_channels = false;
 788
 789         stor_device = get_out_stor_device(device);
 790         if (!stor_device)
 791                 return -ENODEV;
 792
 793         request = &stor_device->init_request;
 794         vstor_packet = &request->vstor_packet;
 795
 796         /*
 797          * Now, initiate the vsc/vsp initialization protocol on the open
 798          * channel
 799          */
 800         memset(request, 0, sizeof(struct storvsc_cmd_request));
 801         vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
 802         ret = storvsc_execute_vstor_op(device, request, true);
 803         if (ret)
 804                 return ret;
 805         /*
 806          * Query host supported protocol version.
 807          */
 808
 809         for (i = 0; i < ARRAY_SIZE(vmstor_protocols); i++) {
 810                 /* reuse the packet for version range supported */
 811                 memset(vstor_packet, 0, sizeof(struct vstor_packet));
 812                 vstor_packet->operation =
 813                         VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
 814
 815                 vstor_packet->version.major_minor =
 816                         vmstor_protocols[i].protocol_version;
 817
 818                 /*
 819                  * The revision number is only used in Windows; set it to 0.
 820                  */
 821                 vstor_packet->version.revision = 0;
 822                 ret = storvsc_execute_vstor_op(device, request, false);
 823                 if (ret != 0)
 824                         return ret;
 825
 826                 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
 827                         return -EINVAL;
 828
 829                 if (vstor_packet->status == 0) {
 830                         vmstor_proto_version =
 831                                 vmstor_protocols[i].protocol_version;
 832
 833                         sense_buffer_size =
 834                                 vmstor_protocols[i].sense_buffer_size;
 835
 836                         vmscsi_size_delta =
 837                                 vmstor_protocols[i].vmscsi_size_delta;
 838
 839                         break;
 840                 }
 841         }
 842
 843         if (vstor_packet->status != 0)
 844                 return -EINVAL;
 845
 846
 847         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 848         vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
 849         ret = storvsc_execute_vstor_op(device, request, true);
 850         if (ret != 0)
 851                 return ret;
 852
 853         /*
 854          * Check to see if multi-channel support is there.
 855          * Hosts that implement protocol version of 5.1 and above
 856          * support multi-channel.
 857          */
 858         max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
 859
 860         /*
 861          * Allocate state to manage the sub-channels.
 862          * We allocate an array based on the numbers of possible CPUs
 863          * (Hyper-V does not support cpu online/offline).
 864          * This Array will be sparseley populated with unique
 865          * channels - primary + sub-channels.
 866          * We will however populate all the slots to evenly distribute
 867          * the load.
 868          */
 869         stor_device->stor_chns = kzalloc(sizeof(void *) * num_possible_cpus(),
 870                                          GFP_KERNEL);
 871         if (stor_device->stor_chns == NULL)
 872                 return -ENOMEM;
 873
 874         stor_device->stor_chns[device->channel->target_cpu] = device->channel;
 875         cpumask_set_cpu(device->channel->target_cpu,
 876                         &stor_device->alloced_cpus);
 877
 878         if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN8) {
 879                 if (vstor_packet->storage_channel_properties.flags &
 880                     STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
 881                         process_sub_channels = true;
 882         }
 883         stor_device->max_transfer_bytes =
 884                 vstor_packet->storage_channel_properties.max_transfer_bytes;
 885
 886         if (!is_fc)
 887                 goto done;
 888
 889         /*
 890          * For FC devices retrieve FC HBA data.
 891          */
 892         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 893         vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
 894         ret = storvsc_execute_vstor_op(device, request, true);
 895         if (ret != 0)
 896                 return ret;
 897
 898         /*
 899          * Cache the currently active port and node ww names.
 900          */
 901         cache_wwn(stor_device, vstor_packet);
 902
 903 done:
 904
 905         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 906         vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
 907         ret = storvsc_execute_vstor_op(device, request, true);
 908         if (ret != 0)
 909                 return ret;
 910
 911         if (process_sub_channels)
 912                 handle_multichannel_storage(device, max_chns);
 913
 914         return ret;
 915 }
 916
 917 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
 918                                 struct scsi_cmnd *scmnd,
 919                                 struct Scsi_Host *host,
 920                                 u8 asc, u8 ascq)
 921 {
 922         struct storvsc_scan_work *wrk;
 923         void (*process_err_fn)(struct work_struct *work);
 924         bool do_work = false;
 925
 926         switch (SRB_STATUS(vm_srb->srb_status)) {
 927         case SRB_STATUS_ERROR:
 928                 /*
 929                  * Let upper layer deal with error when
 930                  * sense message is present.
 931                  */
 932
 933                 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID)
 934                         break;
 935                 /*
 936                  * If there is an error; offline the device since all
 937                  * error recovery strategies would have already been
 938                  * deployed on the host side. However, if the command
 939                  * were a pass-through command deal with it appropriately.
 940                  */
 941                 switch (scmnd->cmnd[0]) {
 942                 case ATA_16:
 943                 case ATA_12:
 944                         set_host_byte(scmnd, DID_PASSTHROUGH);
 945                         break;
 946                 /*
 947                  * On Some Windows hosts TEST_UNIT_READY command can return
 948                  * SRB_STATUS_ERROR, let the upper level code deal with it
 949                  * based on the sense information.
 950                  */
 951                 case TEST_UNIT_READY:
 952                         break;
 953                 default:
 954                         set_host_byte(scmnd, DID_TARGET_FAILURE);
 955                 }
 956                 break;
 957         case SRB_STATUS_INVALID_LUN:
 958                 do_work = true;
 959                 process_err_fn = storvsc_remove_lun;
 960                 break;
 961         case SRB_STATUS_ABORTED:
 962                 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID &&
 963                     (asc == 0x2a) && (ascq == 0x9)) {
 964                         do_work = true;
 965                         process_err_fn = storvsc_device_scan;
 966                         /*
 967                          * Retry the I/O that trigerred this.
 968                          */
 969                         set_host_byte(scmnd, DID_REQUEUE);
 970                 }
 971                 break;
 972         }
 973
 974         if (!do_work)
 975                 return;
 976
 977         /*
 978          * We need to schedule work to process this error; schedule it.
 979          */
 980         wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
 981         if (!wrk) {
 982                 set_host_byte(scmnd, DID_TARGET_FAILURE);
 983                 return;
 984         }
 985
 986         wrk->host = host;
 987         wrk->lun = vm_srb->lun;
 988         wrk->tgt_id = vm_srb->target_id;
 989         INIT_WORK(&wrk->work, process_err_fn);
 990         schedule_work(&wrk->work);
 991 }
 992
 993
 994 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
 995                                        struct storvsc_device *stor_dev)
 996 {
 997         struct scsi_cmnd *scmnd = cmd_request->cmd;
 998         struct scsi_sense_hdr sense_hdr;
 999         struct vmscsi_request *vm_srb;
1000         u32 data_transfer_length;
1001         struct Scsi_Host *host;
1002         u32 payload_sz = cmd_request->payload_sz;
1003         void *payload = cmd_request->payload;
1004
1005         host = stor_dev->host;
1006
1007         vm_srb = &cmd_request->vstor_packet.vm_srb;
1008         data_transfer_length = vm_srb->data_transfer_length;
1009
1010         scmnd->result = vm_srb->scsi_status;
1011
1012         if (scmnd->result) {
1013                 if (scsi_normalize_sense(scmnd->sense_buffer,
1014                                 SCSI_SENSE_BUFFERSIZE, &sense_hdr) &&
1015                     !(sense_hdr.sense_key == NOT_READY &&
1016                                  sense_hdr.asc == 0x03A) &&
1017                     do_logging(STORVSC_LOGGING_ERROR))
1018                         scsi_print_sense_hdr(scmnd->device, "storvsc",
1019                                              &sense_hdr);
1020         }
1021
1022         if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
1023                 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
1024                                          sense_hdr.ascq);
1025                 /*
1026                  * The Windows driver set data_transfer_length on
1027                  * SRB_STATUS_DATA_OVERRUN. On other errors, this value
1028                  * is untouched.  In these cases we set it to 0.
1029                  */
1030                 if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
1031                         data_transfer_length = 0;
1032         }
1033
1034         scsi_set_resid(scmnd,
1035                 cmd_request->payload->range.len - data_transfer_length);
1036
1037         scmnd->scsi_done(scmnd);
1038
1039         if (payload_sz >
1040                 sizeof(struct vmbus_channel_packet_multipage_buffer))
1041                 kfree(payload);
1042 }
1043
1044 static void storvsc_on_io_completion(struct storvsc_device *stor_device,
1045                                   struct vstor_packet *vstor_packet,
1046                                   struct storvsc_cmd_request *request)
1047 {
1048         struct vstor_packet *stor_pkt;
1049         struct hv_device *device = stor_device->device;
1050
1051         stor_pkt = &request->vstor_packet;
1052
1053         /*
1054          * The current SCSI handling on the host side does
1055          * not correctly handle:
1056          * INQUIRY command with page code parameter set to 0x80
1057          * MODE_SENSE command with cmd[2] == 0x1c
1058          *
1059          * Setup srb and scsi status so this won't be fatal.
1060          * We do this so we can distinguish truly fatal failues
1061          * (srb status == 0x4) and off-line the device in that case.
1062          */
1063
1064         if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1065            (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1066                 vstor_packet->vm_srb.scsi_status = 0;
1067                 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1068         }
1069
1070
1071         /* Copy over the status...etc */
1072         stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1073         stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1074         stor_pkt->vm_srb.sense_info_length =
1075         vstor_packet->vm_srb.sense_info_length;
1076
1077         if (vstor_packet->vm_srb.scsi_status != 0 ||
1078             vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS)
1079                 storvsc_log(device, STORVSC_LOGGING_WARN,
1080                         "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
1081                         stor_pkt->vm_srb.cdb[0],
1082                         vstor_packet->vm_srb.scsi_status,
1083                         vstor_packet->vm_srb.srb_status);
1084
1085         if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
1086                 /* CHECK_CONDITION */
1087                 if (vstor_packet->vm_srb.srb_status &
1088                         SRB_STATUS_AUTOSENSE_VALID) {
1089                         /* autosense data available */
1090
1091                         storvsc_log(device, STORVSC_LOGGING_WARN,
1092                                 "stor pkt %p autosense data valid - len %d\n",
1093                                 request, vstor_packet->vm_srb.sense_info_length);
1094
1095                         memcpy(request->cmd->sense_buffer,
1096                                vstor_packet->vm_srb.sense_data,
1097                                vstor_packet->vm_srb.sense_info_length);
1098
1099                 }
1100         }
1101
1102         stor_pkt->vm_srb.data_transfer_length =
1103         vstor_packet->vm_srb.data_transfer_length;
1104
1105         storvsc_command_completion(request, stor_device);
1106
1107         if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1108                 stor_device->drain_notify)
1109                 wake_up(&stor_device->waiting_to_drain);
1110
1111
1112 }
1113
1114 static void storvsc_on_receive(struct storvsc_device *stor_device,
1115                              struct vstor_packet *vstor_packet,
1116                              struct storvsc_cmd_request *request)
1117 {
1118         struct storvsc_scan_work *work;
1119
1120         switch (vstor_packet->operation) {
1121         case VSTOR_OPERATION_COMPLETE_IO:
1122                 storvsc_on_io_completion(stor_device, vstor_packet, request);
1123                 break;
1124
1125         case VSTOR_OPERATION_REMOVE_DEVICE:
1126         case VSTOR_OPERATION_ENUMERATE_BUS:
1127                 work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1128                 if (!work)
1129                         return;
1130
1131                 INIT_WORK(&work->work, storvsc_host_scan);
1132                 work->host = stor_device->host;
1133                 schedule_work(&work->work);
1134                 break;
1135
1136         case VSTOR_OPERATION_FCHBA_DATA:
1137                 cache_wwn(stor_device, vstor_packet);
1138 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1139                 fc_host_node_name(stor_device->host) = stor_device->node_name;
1140                 fc_host_port_name(stor_device->host) = stor_device->port_name;
1141 #endif
1142                 break;
1143         default:
1144                 break;
1145         }
1146 }
1147
1148 static void storvsc_on_channel_callback(void *context)
1149 {
1150         struct vmbus_channel *channel = (struct vmbus_channel *)context;
1151         struct hv_device *device;
1152         struct storvsc_device *stor_device;
1153         u32 bytes_recvd;
1154         u64 request_id;
1155         unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
1156         struct storvsc_cmd_request *request;
1157         int ret;
1158
1159         if (channel->primary_channel != NULL)
1160                 device = channel->primary_channel->device_obj;
1161         else
1162                 device = channel->device_obj;
1163
1164         stor_device = get_in_stor_device(device);
1165         if (!stor_device)
1166                 return;
1167
1168         do {
1169                 ret = vmbus_recvpacket(channel, packet,
1170                                        ALIGN((sizeof(struct vstor_packet) -
1171                                              vmscsi_size_delta), 8),
1172                                        &bytes_recvd, &request_id);
1173                 if (ret == 0 && bytes_recvd > 0) {
1174
1175                         request = (struct storvsc_cmd_request *)
1176                                         (unsigned long)request_id;
1177
1178                         if ((request == &stor_device->init_request) ||
1179                             (request == &stor_device->reset_request)) {
1180
1181                                 memcpy(&request->vstor_packet, packet,
1182                                        (sizeof(struct vstor_packet) -
1183                                         vmscsi_size_delta));
1184                                 complete(&request->wait_event);
1185                         } else {
1186                                 storvsc_on_receive(stor_device,
1187                                                 (struct vstor_packet *)packet,
1188                                                 request);
1189                         }
1190                 } else {
1191                         break;
1192                 }
1193         } while (1);
1194
1195         return;
1196 }
1197
1198 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
1199                                   bool is_fc)
1200 {
1201         struct vmstorage_channel_properties props;
1202         int ret;
1203
1204         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1205
1206         ret = vmbus_open(device->channel,
1207                          ring_size,
1208                          ring_size,
1209                          (void *)&props,
1210                          sizeof(struct vmstorage_channel_properties),
1211                          storvsc_on_channel_callback, device->channel);
1212
1213         if (ret != 0)
1214                 return ret;
1215
1216         ret = storvsc_channel_init(device, is_fc);
1217
1218         return ret;
1219 }
1220
1221 static int storvsc_dev_remove(struct hv_device *device)
1222 {
1223         struct storvsc_device *stor_device;
1224         unsigned long flags;
1225
1226         stor_device = hv_get_drvdata(device);
1227
1228         spin_lock_irqsave(&device->channel->inbound_lock, flags);
1229         stor_device->destroy = true;
1230         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1231
1232         /*
1233          * At this point, all outbound traffic should be disable. We
1234          * only allow inbound traffic (responses) to proceed so that
1235          * outstanding requests can be completed.
1236          */
1237
1238         storvsc_wait_to_drain(stor_device);
1239
1240         /*
1241          * Since we have already drained, we don't need to busy wait
1242          * as was done in final_release_stor_device()
1243          * Note that we cannot set the ext pointer to NULL until
1244          * we have drained - to drain the outgoing packets, we need to
1245          * allow incoming packets.
1246          */
1247         spin_lock_irqsave(&device->channel->inbound_lock, flags);
1248         hv_set_drvdata(device, NULL);
1249         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1250
1251         /* Close the channel */
1252         vmbus_close(device->channel);
1253
1254         kfree(stor_device->stor_chns);
1255         kfree(stor_device);
1256         return 0;
1257 }
1258
1259 static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device,
1260                                         u16 q_num)
1261 {
1262         u16 slot = 0;
1263         u16 hash_qnum;
1264         struct cpumask alloced_mask;
1265         int num_channels, tgt_cpu;
1266
1267         if (stor_device->num_sc == 0)
1268                 return stor_device->device->channel;
1269
1270         /*
1271          * Our channel array is sparsley populated and we
1272          * initiated I/O on a processor/hw-q that does not
1273          * currently have a designated channel. Fix this.
1274          * The strategy is simple:
1275          * I. Ensure NUMA locality
1276          * II. Distribute evenly (best effort)
1277          * III. Mapping is persistent.
1278          */
1279
1280         cpumask_and(&alloced_mask, &stor_device->alloced_cpus,
1281                     cpumask_of_node(cpu_to_node(q_num)));
1282
1283         num_channels = cpumask_weight(&alloced_mask);
1284         if (num_channels == 0)
1285                 return stor_device->device->channel;
1286
1287         hash_qnum = q_num;
1288         while (hash_qnum >= num_channels)
1289                 hash_qnum -= num_channels;
1290
1291         for_each_cpu(tgt_cpu, &alloced_mask) {
1292                 if (slot == hash_qnum)
1293                         break;
1294                 slot++;
1295         }
1296
1297         stor_device->stor_chns[q_num] = stor_device->stor_chns[tgt_cpu];
1298
1299         return stor_device->stor_chns[q_num];
1300 }
1301
1302
1303 static int storvsc_do_io(struct hv_device *device,
1304                          struct storvsc_cmd_request *request, u16 q_num)
1305 {
1306         struct storvsc_device *stor_device;
1307         struct vstor_packet *vstor_packet;
1308         struct vmbus_channel *outgoing_channel;
1309         int ret = 0;
1310         struct cpumask alloced_mask;
1311         int tgt_cpu;
1312
1313         vstor_packet = &request->vstor_packet;
1314         stor_device = get_out_stor_device(device);
1315
1316         if (!stor_device)
1317                 return -ENODEV;
1318
1319
1320         request->device  = device;
1321         /*
1322          * Select an an appropriate channel to send the request out.
1323          */
1324
1325         if (stor_device->stor_chns[q_num] != NULL) {
1326                 outgoing_channel = stor_device->stor_chns[q_num];
1327                 if (outgoing_channel->target_cpu == smp_processor_id()) {
1328                         /*
1329                          * Ideally, we want to pick a different channel if
1330                          * available on the same NUMA node.
1331                          */
1332                         cpumask_and(&alloced_mask, &stor_device->alloced_cpus,
1333                                     cpumask_of_node(cpu_to_node(q_num)));
1334                         for_each_cpu(tgt_cpu, &alloced_mask) {
1335                                 if (tgt_cpu != outgoing_channel->target_cpu) {
1336                                         outgoing_channel =
1337                                         stor_device->stor_chns[tgt_cpu];
1338                                         break;
1339                                 }
1340                         }
1341                 }
1342         } else {
1343                 outgoing_channel = get_og_chn(stor_device, q_num);
1344         }
1345
1346
1347         vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1348
1349         vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) -
1350                                         vmscsi_size_delta);
1351
1352
1353         vstor_packet->vm_srb.sense_info_length = sense_buffer_size;
1354
1355
1356         vstor_packet->vm_srb.data_transfer_length =
1357         request->payload->range.len;
1358
1359         vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1360
1361         if (request->payload->range.len) {
1362
1363                 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1364                                 request->payload, request->payload_sz,
1365                                 vstor_packet,
1366                                 (sizeof(struct vstor_packet) -
1367                                 vmscsi_size_delta),
1368                                 (unsigned long)request);
1369         } else {
1370                 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1371                                (sizeof(struct vstor_packet) -
1372                                 vmscsi_size_delta),
1373                                (unsigned long)request,
1374                                VM_PKT_DATA_INBAND,
1375                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1376         }
1377
1378         if (ret != 0)
1379                 return ret;
1380
1381         atomic_inc(&stor_device->num_outstanding_req);
1382
1383         return ret;
1384 }
1385
1386 static int storvsc_device_configure(struct scsi_device *sdevice)
1387 {
1388
1389         blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
1390
1391         blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1392
1393         /* Ensure there are no gaps in presented sgls */
1394         blk_queue_virt_boundary(sdevice->request_queue, PAGE_SIZE - 1);
1395
1396         sdevice->no_write_same = 1;
1397
1398         /*
1399          * Add blist flags to permit the reading of the VPD pages even when
1400          * the target may claim SPC-2 compliance. MSFT targets currently
1401          * claim SPC-2 compliance while they implement post SPC-2 features.
1402          * With this patch we can correctly handle WRITE_SAME_16 issues.
1403          */
1404         sdevice->sdev_bflags |= msft_blist_flags;
1405
1406         /*
1407          * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1408          * if the device is a MSFT virtual device.  If the host is
1409          * WIN10 or newer, allow write_same.
1410          */
1411         if (!strncmp(sdevice->vendor, "Msft", 4)) {
1412                 switch (vmstor_proto_version) {
1413                 case VMSTOR_PROTO_VERSION_WIN8:
1414                 case VMSTOR_PROTO_VERSION_WIN8_1:
1415                         sdevice->scsi_level = SCSI_SPC_3;
1416                         break;
1417                 }
1418
1419                 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1420                         sdevice->no_write_same = 0;
1421         }
1422
1423         return 0;
1424 }
1425
1426 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1427                            sector_t capacity, int *info)
1428 {
1429         sector_t nsect = capacity;
1430         sector_t cylinders = nsect;
1431         int heads, sectors_pt;
1432
1433         /*
1434          * We are making up these values; let us keep it simple.
1435          */
1436         heads = 0xff;
1437         sectors_pt = 0x3f;      /* Sectors per track */
1438         sector_div(cylinders, heads * sectors_pt);
1439         if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1440                 cylinders = 0xffff;
1441
1442         info[0] = heads;
1443         info[1] = sectors_pt;
1444         info[2] = (int)cylinders;
1445
1446         return 0;
1447 }
1448
1449 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1450 {
1451         struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1452         struct hv_device *device = host_dev->dev;
1453
1454         struct storvsc_device *stor_device;
1455         struct storvsc_cmd_request *request;
1456         struct vstor_packet *vstor_packet;
1457         int ret, t;
1458
1459
1460         stor_device = get_out_stor_device(device);
1461         if (!stor_device)
1462                 return FAILED;
1463
1464         request = &stor_device->reset_request;
1465         vstor_packet = &request->vstor_packet;
1466
1467         init_completion(&request->wait_event);
1468
1469         vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1470         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1471         vstor_packet->vm_srb.path_id = stor_device->path_id;
1472
1473         ret = vmbus_sendpacket(device->channel, vstor_packet,
1474                                (sizeof(struct vstor_packet) -
1475                                 vmscsi_size_delta),
1476                                (unsigned long)&stor_device->reset_request,
1477                                VM_PKT_DATA_INBAND,
1478                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1479         if (ret != 0)
1480                 return FAILED;
1481
1482         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1483         if (t == 0)
1484                 return TIMEOUT_ERROR;
1485
1486
1487         /*
1488          * At this point, all outstanding requests in the adapter
1489          * should have been flushed out and return to us
1490          * There is a potential race here where the host may be in
1491          * the process of responding when we return from here.
1492          * Just wait for all in-transit packets to be accounted for
1493          * before we return from here.
1494          */
1495         storvsc_wait_to_drain(stor_device);
1496
1497         return SUCCESS;
1498 }
1499
1500 /*
1501  * The host guarantees to respond to each command, although I/O latencies might
1502  * be unbounded on Azure.  Reset the timer unconditionally to give the host a
1503  * chance to perform EH.
1504  */
1505 static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1506 {
1507         return BLK_EH_RESET_TIMER;
1508 }
1509
1510 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1511 {
1512         bool allowed = true;
1513         u8 scsi_op = scmnd->cmnd[0];
1514
1515         switch (scsi_op) {
1516         /* the host does not handle WRITE_SAME, log accident usage */
1517         case WRITE_SAME:
1518         /*
1519          * smartd sends this command and the host does not handle
1520          * this. So, don't send it.
1521          */
1522         case SET_WINDOW:
1523                 scmnd->result = ILLEGAL_REQUEST << 16;
1524                 allowed = false;
1525                 break;
1526         default:
1527                 break;
1528         }
1529         return allowed;
1530 }
1531
1532 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1533 {
1534         int ret;
1535         struct hv_host_device *host_dev = shost_priv(host);
1536         struct hv_device *dev = host_dev->dev;
1537         struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1538         int i;
1539         struct scatterlist *sgl;
1540         unsigned int sg_count = 0;
1541         struct vmscsi_request *vm_srb;
1542         struct scatterlist *cur_sgl;
1543         struct vmbus_packet_mpb_array  *payload;
1544         u32 payload_sz;
1545         u32 length;
1546
1547         if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1548                 /*
1549                  * On legacy hosts filter unimplemented commands.
1550                  * Future hosts are expected to correctly handle
1551                  * unsupported commands. Furthermore, it is
1552                  * possible that some of the currently
1553                  * unsupported commands maybe supported in
1554                  * future versions of the host.
1555                  */
1556                 if (!storvsc_scsi_cmd_ok(scmnd)) {
1557                         scmnd->scsi_done(scmnd);
1558                         return 0;
1559                 }
1560         }
1561
1562         /* Setup the cmd request */
1563         cmd_request->cmd = scmnd;
1564
1565         vm_srb = &cmd_request->vstor_packet.vm_srb;
1566         vm_srb->win8_extension.time_out_value = 60;
1567
1568         vm_srb->win8_extension.srb_flags |=
1569                 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1570
1571         if (scmnd->device->tagged_supported) {
1572                 vm_srb->win8_extension.srb_flags |=
1573                 (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
1574                 vm_srb->win8_extension.queue_tag = SP_UNTAGGED;
1575                 vm_srb->win8_extension.queue_action = SRB_SIMPLE_TAG_REQUEST;
1576         }
1577
1578         /* Build the SRB */
1579         switch (scmnd->sc_data_direction) {
1580         case DMA_TO_DEVICE:
1581                 vm_srb->data_in = WRITE_TYPE;
1582                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_OUT;
1583                 break;
1584         case DMA_FROM_DEVICE:
1585                 vm_srb->data_in = READ_TYPE;
1586                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_IN;
1587                 break;
1588         case DMA_NONE:
1589                 vm_srb->data_in = UNKNOWN_TYPE;
1590                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1591                 break;
1592         default:
1593                 /*
1594                  * This is DMA_BIDIRECTIONAL or something else we are never
1595                  * supposed to see here.
1596                  */
1597                 WARN(1, "Unexpected data direction: %d\n",
1598                      scmnd->sc_data_direction);
1599                 return -EINVAL;
1600         }
1601
1602
1603         vm_srb->port_number = host_dev->port;
1604         vm_srb->path_id = scmnd->device->channel;
1605         vm_srb->target_id = scmnd->device->id;
1606         vm_srb->lun = scmnd->device->lun;
1607
1608         vm_srb->cdb_length = scmnd->cmd_len;
1609
1610         memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1611
1612         sgl = (struct scatterlist *)scsi_sglist(scmnd);
1613         sg_count = scsi_sg_count(scmnd);
1614
1615         length = scsi_bufflen(scmnd);
1616         payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1617         payload_sz = sizeof(cmd_request->mpb);
1618
1619         if (sg_count) {
1620                 if (sg_count > MAX_PAGE_BUFFER_COUNT) {
1621
1622                         payload_sz = (sg_count * sizeof(u64) +
1623                                       sizeof(struct vmbus_packet_mpb_array));
1624                         payload = kzalloc(payload_sz, GFP_ATOMIC);
1625                         if (!payload)
1626                                 return SCSI_MLQUEUE_DEVICE_BUSY;
1627                 }
1628
1629                 payload->range.len = length;
1630                 payload->range.offset = sgl[0].offset;
1631
1632                 cur_sgl = sgl;
1633                 for (i = 0; i < sg_count; i++) {
1634                         payload->range.pfn_array[i] =
1635                                 page_to_pfn(sg_page((cur_sgl)));
1636                         cur_sgl = sg_next(cur_sgl);
1637                 }
1638         }
1639
1640         cmd_request->payload = payload;
1641         cmd_request->payload_sz = payload_sz;
1642
1643         /* Invokes the vsc to start an IO */
1644         ret = storvsc_do_io(dev, cmd_request, get_cpu());
1645         put_cpu();
1646
1647         if (ret == -EAGAIN) {
1648                 /* no more space */
1649                 return SCSI_MLQUEUE_DEVICE_BUSY;
1650         }
1651
1652         return 0;
1653 }
1654
1655 static struct scsi_host_template scsi_driver = {
1656         .module =               THIS_MODULE,
1657         .name =                 "storvsc_host_t",
1658         .cmd_size =             sizeof(struct storvsc_cmd_request),
1659         .bios_param =           storvsc_get_chs,
1660         .queuecommand =         storvsc_queuecommand,
1661         .eh_host_reset_handler =        storvsc_host_reset_handler,
1662         .proc_name =            "storvsc_host",
1663         .eh_timed_out =         storvsc_eh_timed_out,
1664         .slave_configure =      storvsc_device_configure,
1665         .cmd_per_lun =          255,
1666         .this_id =              -1,
1667         .use_clustering =       ENABLE_CLUSTERING,
1668         /* Make sure we dont get a sg segment crosses a page boundary */
1669         .dma_boundary =         PAGE_SIZE-1,
1670         .no_write_same =        1,
1671         .track_queue_depth =    1,
1672 };
1673
1674 enum {
1675         SCSI_GUID,
1676         IDE_GUID,
1677         SFC_GUID,
1678 };
1679
1680 static const struct hv_vmbus_device_id id_table[] = {
1681         /* SCSI guid */
1682         { HV_SCSI_GUID,
1683           .driver_data = SCSI_GUID
1684         },
1685         /* IDE guid */
1686         { HV_IDE_GUID,
1687           .driver_data = IDE_GUID
1688         },
1689         /* Fibre Channel GUID */
1690         {
1691           HV_SYNTHFC_GUID,
1692           .driver_data = SFC_GUID
1693         },
1694         { },
1695 };
1696
1697 MODULE_DEVICE_TABLE(vmbus, id_table);
1698
1699 static int storvsc_probe(struct hv_device *device,
1700                         const struct hv_vmbus_device_id *dev_id)
1701 {
1702         int ret;
1703         int num_cpus = num_online_cpus();
1704         struct Scsi_Host *host;
1705         struct hv_host_device *host_dev;
1706         bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1707         bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
1708         int target = 0;
1709         struct storvsc_device *stor_device;
1710         int max_luns_per_target;
1711         int max_targets;
1712         int max_channels;
1713         int max_sub_channels = 0;
1714
1715         /*
1716          * Based on the windows host we are running on,
1717          * set state to properly communicate with the host.
1718          */
1719
1720         if (vmbus_proto_version < VERSION_WIN8) {
1721                 max_luns_per_target = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1722                 max_targets = STORVSC_IDE_MAX_TARGETS;
1723                 max_channels = STORVSC_IDE_MAX_CHANNELS;
1724         } else {
1725                 max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET;
1726                 max_targets = STORVSC_MAX_TARGETS;
1727                 max_channels = STORVSC_MAX_CHANNELS;
1728                 /*
1729                  * On Windows8 and above, we support sub-channels for storage.
1730                  * The number of sub-channels offerred is based on the number of
1731                  * VCPUs in the guest.
1732                  */
1733                 max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel);
1734         }
1735
1736         scsi_driver.can_queue = (max_outstanding_req_per_channel *
1737                                  (max_sub_channels + 1));
1738
1739         host = scsi_host_alloc(&scsi_driver,
1740                                sizeof(struct hv_host_device));
1741         if (!host)
1742                 return -ENOMEM;
1743
1744         host_dev = shost_priv(host);
1745         memset(host_dev, 0, sizeof(struct hv_host_device));
1746
1747         host_dev->port = host->host_no;
1748         host_dev->dev = device;
1749
1750
1751         stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
1752         if (!stor_device) {
1753                 ret = -ENOMEM;
1754                 goto err_out0;
1755         }
1756
1757         stor_device->destroy = false;
1758         stor_device->open_sub_channel = false;
1759         init_waitqueue_head(&stor_device->waiting_to_drain);
1760         stor_device->device = device;
1761         stor_device->host = host;
1762         hv_set_drvdata(device, stor_device);
1763
1764         stor_device->port_number = host->host_no;
1765         ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size, is_fc);
1766         if (ret)
1767                 goto err_out1;
1768
1769         host_dev->path = stor_device->path_id;
1770         host_dev->target = stor_device->target_id;
1771
1772         switch (dev_id->driver_data) {
1773         case SFC_GUID:
1774                 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
1775                 host->max_id = STORVSC_FC_MAX_TARGETS;
1776                 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
1777 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1778                 host->transportt = fc_transport_template;
1779 #endif
1780                 break;
1781
1782         case SCSI_GUID:
1783                 host->max_lun = max_luns_per_target;
1784                 host->max_id = max_targets;
1785                 host->max_channel = max_channels - 1;
1786                 break;
1787
1788         default:
1789                 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1790                 host->max_id = STORVSC_IDE_MAX_TARGETS;
1791                 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
1792                 break;
1793         }
1794         /* max cmd length */
1795         host->max_cmd_len = STORVSC_MAX_CMD_LEN;
1796
1797         /*
1798          * set the table size based on the info we got
1799          * from the host.
1800          */
1801         host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
1802         /*
1803          * Set the number of HW queues we are supporting.
1804          */
1805         if (stor_device->num_sc != 0)
1806                 host->nr_hw_queues = stor_device->num_sc + 1;
1807
1808         /* Register the HBA and start the scsi bus scan */
1809         ret = scsi_add_host(host, &device->device);
1810         if (ret != 0)
1811                 goto err_out2;
1812
1813         if (!dev_is_ide) {
1814                 scsi_scan_host(host);
1815         } else {
1816                 target = (device->dev_instance.b[5] << 8 |
1817                          device->dev_instance.b[4]);
1818                 ret = scsi_add_device(host, 0, target, 0);
1819                 if (ret) {
1820                         scsi_remove_host(host);
1821                         goto err_out2;
1822                 }
1823         }
1824 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1825         if (host->transportt == fc_transport_template) {
1826                 fc_host_node_name(host) = stor_device->node_name;
1827                 fc_host_port_name(host) = stor_device->port_name;
1828         }
1829 #endif
1830         return 0;
1831
1832 err_out2:
1833         /*
1834          * Once we have connected with the host, we would need to
1835          * to invoke storvsc_dev_remove() to rollback this state and
1836          * this call also frees up the stor_device; hence the jump around
1837          * err_out1 label.
1838          */
1839         storvsc_dev_remove(device);
1840         goto err_out0;
1841
1842 err_out1:
1843         kfree(stor_device->stor_chns);
1844         kfree(stor_device);
1845
1846 err_out0:
1847         scsi_host_put(host);
1848         return ret;
1849 }
1850
1851 static int storvsc_remove(struct hv_device *dev)
1852 {
1853         struct storvsc_device *stor_device = hv_get_drvdata(dev);
1854         struct Scsi_Host *host = stor_device->host;
1855
1856 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1857         if (host->transportt == fc_transport_template)
1858                 fc_remove_host(host);
1859 #endif
1860         scsi_remove_host(host);
1861         storvsc_dev_remove(dev);
1862         scsi_host_put(host);
1863
1864         return 0;
1865 }
1866
1867 static struct hv_driver storvsc_drv = {
1868         .name = KBUILD_MODNAME,
1869         .id_table = id_table,
1870         .probe = storvsc_probe,
1871         .remove = storvsc_remove,
1872 };
1873
1874 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1875 static struct fc_function_template fc_transport_functions = {
1876         .show_host_node_name = 1,
1877         .show_host_port_name = 1,
1878 };
1879 #endif
1880
1881 static int __init storvsc_drv_init(void)
1882 {
1883         int ret;
1884
1885         /*
1886          * Divide the ring buffer data size (which is 1 page less
1887          * than the ring buffer size since that page is reserved for
1888          * the ring buffer indices) by the max request size (which is
1889          * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
1890          */
1891         max_outstanding_req_per_channel =
1892                 ((storvsc_ringbuffer_size - PAGE_SIZE) /
1893                 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
1894                 sizeof(struct vstor_packet) + sizeof(u64) -
1895                 vmscsi_size_delta,
1896                 sizeof(u64)));
1897
1898 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1899         fc_transport_template = fc_attach_transport(&fc_transport_functions);
1900         if (!fc_transport_template)
1901                 return -ENODEV;
1902 #endif
1903
1904         ret = vmbus_driver_register(&storvsc_drv);
1905
1906 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1907         if (ret)
1908                 fc_release_transport(fc_transport_template);
1909 #endif
1910
1911         return ret;
1912 }
1913
1914 static void __exit storvsc_drv_exit(void)
1915 {
1916         vmbus_driver_unregister(&storvsc_drv);
1917 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1918         fc_release_transport(fc_transport_template);
1919 #endif
1920 }
1921
1922 MODULE_LICENSE("GPL");
1923 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
1924 module_init(storvsc_drv_init);
1925 module_exit(storvsc_drv_exit);