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 initialization 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 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
 404 static struct scsi_transport_template *fc_transport_template;
 405 #endif
 406
 407 static void storvsc_on_channel_callback(void *context);
 408
 409 #define STORVSC_MAX_LUNS_PER_TARGET                     255
 410 #define STORVSC_MAX_TARGETS                             2
 411 #define STORVSC_MAX_CHANNELS                            8
 412
 413 #define STORVSC_FC_MAX_LUNS_PER_TARGET                  255
 414 #define STORVSC_FC_MAX_TARGETS                          128
 415 #define STORVSC_FC_MAX_CHANNELS                         8
 416
 417 #define STORVSC_IDE_MAX_LUNS_PER_TARGET                 64
 418 #define STORVSC_IDE_MAX_TARGETS                         1
 419 #define STORVSC_IDE_MAX_CHANNELS                        1
 420
 421 struct storvsc_cmd_request {
 422         struct scsi_cmnd *cmd;
 423
 424         struct hv_device *device;
 425
 426         /* Synchronize the request/response if needed */
 427         struct completion wait_event;
 428
 429         struct vmbus_channel_packet_multipage_buffer mpb;
 430         struct vmbus_packet_mpb_array *payload;
 431         u32 payload_sz;
 432
 433         struct vstor_packet vstor_packet;
 434 };
 435
 436
 437 /* A storvsc device is a device object that contains a vmbus channel */
 438 struct storvsc_device {
 439         struct hv_device *device;
 440
 441         bool     destroy;
 442         bool     drain_notify;
 443         bool     open_sub_channel;
 444         atomic_t num_outstanding_req;
 445         struct Scsi_Host *host;
 446
 447         wait_queue_head_t waiting_to_drain;
 448
 449         /*
 450          * Each unique Port/Path/Target represents 1 channel ie scsi
 451          * controller. In reality, the pathid, targetid is always 0
 452          * and the port is set by us
 453          */
 454         unsigned int port_number;
 455         unsigned char path_id;
 456         unsigned char target_id;
 457
 458         /*
 459          * Max I/O, the device can support.
 460          */
 461         u32   max_transfer_bytes;
 462         /*
 463          * Number of sub-channels we will open.
 464          */
 465         u16 num_sc;
 466         struct vmbus_channel **stor_chns;
 467         /*
 468          * Mask of CPUs bound to subchannels.
 469          */
 470         struct cpumask alloced_cpus;
 471         /* Used for vsc/vsp channel reset process */
 472         struct storvsc_cmd_request init_request;
 473         struct storvsc_cmd_request reset_request;
 474         /*
 475          * Currently active port and node names for FC devices.
 476          */
 477         u64 node_name;
 478         u64 port_name;
 479 };
 480
 481 struct hv_host_device {
 482         struct hv_device *dev;
 483         unsigned int port;
 484         unsigned char path;
 485         unsigned char target;
 486 };
 487
 488 struct storvsc_scan_work {
 489         struct work_struct work;
 490         struct Scsi_Host *host;
 491         u8 lun;
 492         u8 tgt_id;
 493 };
 494
 495 static void storvsc_device_scan(struct work_struct *work)
 496 {
 497         struct storvsc_scan_work *wrk;
 498         struct scsi_device *sdev;
 499
 500         wrk = container_of(work, struct storvsc_scan_work, work);
 501
 502         sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
 503         if (!sdev)
 504                 goto done;
 505         scsi_rescan_device(&sdev->sdev_gendev);
 506         scsi_device_put(sdev);
 507
 508 done:
 509         kfree(wrk);
 510 }
 511
 512 static void storvsc_host_scan(struct work_struct *work)
 513 {
 514         struct storvsc_scan_work *wrk;
 515         struct Scsi_Host *host;
 516         struct scsi_device *sdev;
 517
 518         wrk = container_of(work, struct storvsc_scan_work, work);
 519         host = wrk->host;
 520
 521         /*
 522          * Before scanning the host, first check to see if any of the
 523          * currrently known devices have been hot removed. We issue a
 524          * "unit ready" command against all currently known devices.
 525          * This I/O will result in an error for devices that have been
 526          * removed. As part of handling the I/O error, we remove the device.
 527          *
 528          * When a LUN is added or removed, the host sends us a signal to
 529          * scan the host. Thus we are forced to discover the LUNs that
 530          * may have been removed this way.
 531          */
 532         mutex_lock(&host->scan_mutex);
 533         shost_for_each_device(sdev, host)
 534                 scsi_test_unit_ready(sdev, 1, 1, NULL);
 535         mutex_unlock(&host->scan_mutex);
 536         /*
 537          * Now scan the host to discover LUNs that may have been added.
 538          */
 539         scsi_scan_host(host);
 540
 541         kfree(wrk);
 542 }
 543
 544 static void storvsc_remove_lun(struct work_struct *work)
 545 {
 546         struct storvsc_scan_work *wrk;
 547         struct scsi_device *sdev;
 548
 549         wrk = container_of(work, struct storvsc_scan_work, work);
 550         if (!scsi_host_get(wrk->host))
 551                 goto done;
 552
 553         sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
 554
 555         if (sdev) {
 556                 scsi_remove_device(sdev);
 557                 scsi_device_put(sdev);
 558         }
 559         scsi_host_put(wrk->host);
 560
 561 done:
 562         kfree(wrk);
 563 }
 564
 565
 566 /*
 567  * We can get incoming messages from the host that are not in response to
 568  * messages that we have sent out. An example of this would be messages
 569  * received by the guest to notify dynamic addition/removal of LUNs. To
 570  * deal with potential race conditions where the driver may be in the
 571  * midst of being unloaded when we might receive an unsolicited message
 572  * from the host, we have implemented a mechanism to gurantee sequential
 573  * consistency:
 574  *
 575  * 1) Once the device is marked as being destroyed, we will fail all
 576  *    outgoing messages.
 577  * 2) We permit incoming messages when the device is being destroyed,
 578  *    only to properly account for messages already sent out.
 579  */
 580
 581 static inline struct storvsc_device *get_out_stor_device(
 582                                         struct hv_device *device)
 583 {
 584         struct storvsc_device *stor_device;
 585
 586         stor_device = hv_get_drvdata(device);
 587
 588         if (stor_device && stor_device->destroy)
 589                 stor_device = NULL;
 590
 591         return stor_device;
 592 }
 593
 594
 595 static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
 596 {
 597         dev->drain_notify = true;
 598         wait_event(dev->waiting_to_drain,
 599                    atomic_read(&dev->num_outstanding_req) == 0);
 600         dev->drain_notify = false;
 601 }
 602
 603 static inline struct storvsc_device *get_in_stor_device(
 604                                         struct hv_device *device)
 605 {
 606         struct storvsc_device *stor_device;
 607
 608         stor_device = hv_get_drvdata(device);
 609
 610         if (!stor_device)
 611                 goto get_in_err;
 612
 613         /*
 614          * If the device is being destroyed; allow incoming
 615          * traffic only to cleanup outstanding requests.
 616          */
 617
 618         if (stor_device->destroy  &&
 619                 (atomic_read(&stor_device->num_outstanding_req) == 0))
 620                 stor_device = NULL;
 621
 622 get_in_err:
 623         return stor_device;
 624
 625 }
 626
 627 static void handle_sc_creation(struct vmbus_channel *new_sc)
 628 {
 629         struct hv_device *device = new_sc->primary_channel->device_obj;
 630         struct storvsc_device *stor_device;
 631         struct vmstorage_channel_properties props;
 632
 633         stor_device = get_out_stor_device(device);
 634         if (!stor_device)
 635                 return;
 636
 637         if (stor_device->open_sub_channel == false)
 638                 return;
 639
 640         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
 641
 642         vmbus_open(new_sc,
 643                    storvsc_ringbuffer_size,
 644                    storvsc_ringbuffer_size,
 645                    (void *)&props,
 646                    sizeof(struct vmstorage_channel_properties),
 647                    storvsc_on_channel_callback, new_sc);
 648
 649         if (new_sc->state == CHANNEL_OPENED_STATE) {
 650                 stor_device->stor_chns[new_sc->target_cpu] = new_sc;
 651                 cpumask_set_cpu(new_sc->target_cpu, &stor_device->alloced_cpus);
 652         }
 653 }
 654
 655 static void  handle_multichannel_storage(struct hv_device *device, int max_chns)
 656 {
 657         struct storvsc_device *stor_device;
 658         int num_cpus = num_online_cpus();
 659         int num_sc;
 660         struct storvsc_cmd_request *request;
 661         struct vstor_packet *vstor_packet;
 662         int ret, t;
 663
 664         num_sc = ((max_chns > num_cpus) ? num_cpus : max_chns);
 665         stor_device = get_out_stor_device(device);
 666         if (!stor_device)
 667                 return;
 668
 669         stor_device->num_sc = num_sc;
 670         request = &stor_device->init_request;
 671         vstor_packet = &request->vstor_packet;
 672
 673         stor_device->open_sub_channel = true;
 674         /*
 675          * Establish a handler for dealing with subchannels.
 676          */
 677         vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
 678
 679         /*
 680          * Check to see if sub-channels have already been created. This
 681          * can happen when this driver is re-loaded after unloading.
 682          */
 683
 684         if (vmbus_are_subchannels_present(device->channel))
 685                 return;
 686
 687         stor_device->open_sub_channel = false;
 688         /*
 689          * Request the host to create sub-channels.
 690          */
 691         memset(request, 0, sizeof(struct storvsc_cmd_request));
 692         init_completion(&request->wait_event);
 693         vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
 694         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 695         vstor_packet->sub_channel_count = num_sc;
 696
 697         ret = vmbus_sendpacket(device->channel, vstor_packet,
 698                                (sizeof(struct vstor_packet) -
 699                                vmscsi_size_delta),
 700                                (unsigned long)request,
 701                                VM_PKT_DATA_INBAND,
 702                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 703
 704         if (ret != 0)
 705                 return;
 706
 707         t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
 708         if (t == 0)
 709                 return;
 710
 711         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 712             vstor_packet->status != 0)
 713                 return;
 714
 715         /*
 716          * Now that we created the sub-channels, invoke the check; this
 717          * may trigger the callback.
 718          */
 719         stor_device->open_sub_channel = true;
 720         vmbus_are_subchannels_present(device->channel);
 721 }
 722
 723 static void cache_wwn(struct storvsc_device *stor_device,
 724                       struct vstor_packet *vstor_packet)
 725 {
 726         /*
 727          * Cache the currently active port and node ww names.
 728          */
 729         if (vstor_packet->wwn_packet.primary_active) {
 730                 stor_device->node_name =
 731                         wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
 732                 stor_device->port_name =
 733                         wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
 734         } else {
 735                 stor_device->node_name =
 736                         wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
 737                 stor_device->port_name =
 738                         wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
 739         }
 740 }
 741
 742
 743 static int storvsc_execute_vstor_op(struct hv_device *device,
 744                                     struct storvsc_cmd_request *request,
 745                                     bool status_check)
 746 {
 747         struct vstor_packet *vstor_packet;
 748         int ret, t;
 749
 750         vstor_packet = &request->vstor_packet;
 751
 752         init_completion(&request->wait_event);
 753         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 754
 755         ret = vmbus_sendpacket(device->channel, vstor_packet,
 756                                (sizeof(struct vstor_packet) -
 757                                vmscsi_size_delta),
 758                                (unsigned long)request,
 759                                VM_PKT_DATA_INBAND,
 760                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 761         if (ret != 0)
 762                 return ret;
 763
 764         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
 765         if (t == 0)
 766                 return -ETIMEDOUT;
 767
 768         if (!status_check)
 769                 return ret;
 770
 771         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 772             vstor_packet->status != 0)
 773                 return -EINVAL;
 774
 775         return ret;
 776 }
 777
 778 static int storvsc_channel_init(struct hv_device *device, bool is_fc)
 779 {
 780         struct storvsc_device *stor_device;
 781         struct storvsc_cmd_request *request;
 782         struct vstor_packet *vstor_packet;
 783         int ret, i;
 784         int max_chns;
 785         bool process_sub_channels = false;
 786
 787         stor_device = get_out_stor_device(device);
 788         if (!stor_device)
 789                 return -ENODEV;
 790
 791         request = &stor_device->init_request;
 792         vstor_packet = &request->vstor_packet;
 793
 794         /*
 795          * Now, initiate the vsc/vsp initialization protocol on the open
 796          * channel
 797          */
 798         memset(request, 0, sizeof(struct storvsc_cmd_request));
 799         vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
 800         ret = storvsc_execute_vstor_op(device, request, true);
 801         if (ret)
 802                 return ret;
 803         /*
 804          * Query host supported protocol version.
 805          */
 806
 807         for (i = 0; i < ARRAY_SIZE(vmstor_protocols); i++) {
 808                 /* reuse the packet for version range supported */
 809                 memset(vstor_packet, 0, sizeof(struct vstor_packet));
 810                 vstor_packet->operation =
 811                         VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
 812
 813                 vstor_packet->version.major_minor =
 814                         vmstor_protocols[i].protocol_version;
 815
 816                 /*
 817                  * The revision number is only used in Windows; set it to 0.
 818                  */
 819                 vstor_packet->version.revision = 0;
 820                 ret = storvsc_execute_vstor_op(device, request, false);
 821                 if (ret != 0)
 822                         return ret;
 823
 824                 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
 825                         return -EINVAL;
 826
 827                 if (vstor_packet->status == 0) {
 828                         vmstor_proto_version =
 829                                 vmstor_protocols[i].protocol_version;
 830
 831                         sense_buffer_size =
 832                                 vmstor_protocols[i].sense_buffer_size;
 833
 834                         vmscsi_size_delta =
 835                                 vmstor_protocols[i].vmscsi_size_delta;
 836
 837                         break;
 838                 }
 839         }
 840
 841         if (vstor_packet->status != 0)
 842                 return -EINVAL;
 843
 844
 845         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 846         vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
 847         ret = storvsc_execute_vstor_op(device, request, true);
 848         if (ret != 0)
 849                 return ret;
 850
 851         /*
 852          * Check to see if multi-channel support is there.
 853          * Hosts that implement protocol version of 5.1 and above
 854          * support multi-channel.
 855          */
 856         max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
 857
 858         /*
 859          * Allocate state to manage the sub-channels.
 860          * We allocate an array based on the numbers of possible CPUs
 861          * (Hyper-V does not support cpu online/offline).
 862          * This Array will be sparseley populated with unique
 863          * channels - primary + sub-channels.
 864          * We will however populate all the slots to evenly distribute
 865          * the load.
 866          */
 867         stor_device->stor_chns = kzalloc(sizeof(void *) * num_possible_cpus(),
 868                                          GFP_KERNEL);
 869         if (stor_device->stor_chns == NULL)
 870                 return -ENOMEM;
 871
 872         stor_device->stor_chns[device->channel->target_cpu] = device->channel;
 873         cpumask_set_cpu(device->channel->target_cpu,
 874                         &stor_device->alloced_cpus);
 875
 876         if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN8) {
 877                 if (vstor_packet->storage_channel_properties.flags &
 878                     STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
 879                         process_sub_channels = true;
 880         }
 881         stor_device->max_transfer_bytes =
 882                 vstor_packet->storage_channel_properties.max_transfer_bytes;
 883
 884         if (!is_fc)
 885                 goto done;
 886
 887         /*
 888          * For FC devices retrieve FC HBA data.
 889          */
 890         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 891         vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
 892         ret = storvsc_execute_vstor_op(device, request, true);
 893         if (ret != 0)
 894                 return ret;
 895
 896         /*
 897          * Cache the currently active port and node ww names.
 898          */
 899         cache_wwn(stor_device, vstor_packet);
 900
 901 done:
 902
 903         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 904         vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
 905         ret = storvsc_execute_vstor_op(device, request, true);
 906         if (ret != 0)
 907                 return ret;
 908
 909         if (process_sub_channels)
 910                 handle_multichannel_storage(device, max_chns);
 911
 912         return ret;
 913 }
 914
 915 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
 916                                 struct scsi_cmnd *scmnd,
 917                                 struct Scsi_Host *host,
 918                                 u8 asc, u8 ascq)
 919 {
 920         struct storvsc_scan_work *wrk;
 921         void (*process_err_fn)(struct work_struct *work);
 922         bool do_work = false;
 923
 924         switch (SRB_STATUS(vm_srb->srb_status)) {
 925         case SRB_STATUS_ERROR:
 926                 /*
 927                  * Let upper layer deal with error when
 928                  * sense message is present.
 929                  */
 930
 931                 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID)
 932                         break;
 933                 /*
 934                  * If there is an error; offline the device since all
 935                  * error recovery strategies would have already been
 936                  * deployed on the host side. However, if the command
 937                  * were a pass-through command deal with it appropriately.
 938                  */
 939                 switch (scmnd->cmnd[0]) {
 940                 case ATA_16:
 941                 case ATA_12:
 942                         set_host_byte(scmnd, DID_PASSTHROUGH);
 943                         break;
 944                 /*
 945                  * On Some Windows hosts TEST_UNIT_READY command can return
 946                  * SRB_STATUS_ERROR, let the upper level code deal with it
 947                  * based on the sense information.
 948                  */
 949                 case TEST_UNIT_READY:
 950                         break;
 951                 default:
 952                         set_host_byte(scmnd, DID_TARGET_FAILURE);
 953                 }
 954                 break;
 955         case SRB_STATUS_INVALID_LUN:
 956                 do_work = true;
 957                 process_err_fn = storvsc_remove_lun;
 958                 break;
 959         case SRB_STATUS_ABORTED:
 960                 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID &&
 961                     (asc == 0x2a) && (ascq == 0x9)) {
 962                         do_work = true;
 963                         process_err_fn = storvsc_device_scan;
 964                         /*
 965                          * Retry the I/O that trigerred this.
 966                          */
 967                         set_host_byte(scmnd, DID_REQUEUE);
 968                 }
 969                 break;
 970         }
 971
 972         if (!do_work)
 973                 return;
 974
 975         /*
 976          * We need to schedule work to process this error; schedule it.
 977          */
 978         wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
 979         if (!wrk) {
 980                 set_host_byte(scmnd, DID_TARGET_FAILURE);
 981                 return;
 982         }
 983
 984         wrk->host = host;
 985         wrk->lun = vm_srb->lun;
 986         wrk->tgt_id = vm_srb->target_id;
 987         INIT_WORK(&wrk->work, process_err_fn);
 988         schedule_work(&wrk->work);
 989 }
 990
 991
 992 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
 993                                        struct storvsc_device *stor_dev)
 994 {
 995         struct scsi_cmnd *scmnd = cmd_request->cmd;
 996         struct scsi_sense_hdr sense_hdr;
 997         struct vmscsi_request *vm_srb;
 998         u32 data_transfer_length;
 999         struct Scsi_Host *host;
1000         u32 payload_sz = cmd_request->payload_sz;
1001         void *payload = cmd_request->payload;
1002
1003         host = stor_dev->host;
1004
1005         vm_srb = &cmd_request->vstor_packet.vm_srb;
1006         data_transfer_length = vm_srb->data_transfer_length;
1007
1008         scmnd->result = vm_srb->scsi_status;
1009
1010         if (scmnd->result) {
1011                 if (scsi_normalize_sense(scmnd->sense_buffer,
1012                                 SCSI_SENSE_BUFFERSIZE, &sense_hdr) &&
1013                     !(sense_hdr.sense_key == NOT_READY &&
1014                                  sense_hdr.asc == 0x03A) &&
1015                     do_logging(STORVSC_LOGGING_ERROR))
1016                         scsi_print_sense_hdr(scmnd->device, "storvsc",
1017                                              &sense_hdr);
1018         }
1019
1020         if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
1021                 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
1022                                          sense_hdr.ascq);
1023                 /*
1024                  * The Windows driver set data_transfer_length on
1025                  * SRB_STATUS_DATA_OVERRUN. On other errors, this value
1026                  * is untouched.  In these cases we set it to 0.
1027                  */
1028                 if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
1029                         data_transfer_length = 0;
1030         }
1031
1032         scsi_set_resid(scmnd,
1033                 cmd_request->payload->range.len - data_transfer_length);
1034
1035         scmnd->scsi_done(scmnd);
1036
1037         if (payload_sz >
1038                 sizeof(struct vmbus_channel_packet_multipage_buffer))
1039                 kfree(payload);
1040 }
1041
1042 static void storvsc_on_io_completion(struct storvsc_device *stor_device,
1043                                   struct vstor_packet *vstor_packet,
1044                                   struct storvsc_cmd_request *request)
1045 {
1046         struct vstor_packet *stor_pkt;
1047         struct hv_device *device = stor_device->device;
1048
1049         stor_pkt = &request->vstor_packet;
1050
1051         /*
1052          * The current SCSI handling on the host side does
1053          * not correctly handle:
1054          * INQUIRY command with page code parameter set to 0x80
1055          * MODE_SENSE command with cmd[2] == 0x1c
1056          *
1057          * Setup srb and scsi status so this won't be fatal.
1058          * We do this so we can distinguish truly fatal failues
1059          * (srb status == 0x4) and off-line the device in that case.
1060          */
1061
1062         if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1063            (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1064                 vstor_packet->vm_srb.scsi_status = 0;
1065                 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1066         }
1067
1068
1069         /* Copy over the status...etc */
1070         stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1071         stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1072         stor_pkt->vm_srb.sense_info_length =
1073         vstor_packet->vm_srb.sense_info_length;
1074
1075         if (vstor_packet->vm_srb.scsi_status != 0 ||
1076             vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS)
1077                 storvsc_log(device, STORVSC_LOGGING_WARN,
1078                         "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
1079                         stor_pkt->vm_srb.cdb[0],
1080                         vstor_packet->vm_srb.scsi_status,
1081                         vstor_packet->vm_srb.srb_status);
1082
1083         if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
1084                 /* CHECK_CONDITION */
1085                 if (vstor_packet->vm_srb.srb_status &
1086                         SRB_STATUS_AUTOSENSE_VALID) {
1087                         /* autosense data available */
1088
1089                         storvsc_log(device, STORVSC_LOGGING_WARN,
1090                                 "stor pkt %p autosense data valid - len %d\n",
1091                                 request, vstor_packet->vm_srb.sense_info_length);
1092
1093                         memcpy(request->cmd->sense_buffer,
1094                                vstor_packet->vm_srb.sense_data,
1095                                vstor_packet->vm_srb.sense_info_length);
1096
1097                 }
1098         }
1099
1100         stor_pkt->vm_srb.data_transfer_length =
1101         vstor_packet->vm_srb.data_transfer_length;
1102
1103         storvsc_command_completion(request, stor_device);
1104
1105         if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1106                 stor_device->drain_notify)
1107                 wake_up(&stor_device->waiting_to_drain);
1108
1109
1110 }
1111
1112 static void storvsc_on_receive(struct storvsc_device *stor_device,
1113                              struct vstor_packet *vstor_packet,
1114                              struct storvsc_cmd_request *request)
1115 {
1116         struct storvsc_scan_work *work;
1117
1118         switch (vstor_packet->operation) {
1119         case VSTOR_OPERATION_COMPLETE_IO:
1120                 storvsc_on_io_completion(stor_device, vstor_packet, request);
1121                 break;
1122
1123         case VSTOR_OPERATION_REMOVE_DEVICE:
1124         case VSTOR_OPERATION_ENUMERATE_BUS:
1125                 work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1126                 if (!work)
1127                         return;
1128
1129                 INIT_WORK(&work->work, storvsc_host_scan);
1130                 work->host = stor_device->host;
1131                 schedule_work(&work->work);
1132                 break;
1133
1134         case VSTOR_OPERATION_FCHBA_DATA:
1135                 cache_wwn(stor_device, vstor_packet);
1136 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1137                 fc_host_node_name(stor_device->host) = stor_device->node_name;
1138                 fc_host_port_name(stor_device->host) = stor_device->port_name;
1139 #endif
1140                 break;
1141         default:
1142                 break;
1143         }
1144 }
1145
1146 static void storvsc_on_channel_callback(void *context)
1147 {
1148         struct vmbus_channel *channel = (struct vmbus_channel *)context;
1149         struct hv_device *device;
1150         struct storvsc_device *stor_device;
1151         u32 bytes_recvd;
1152         u64 request_id;
1153         unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
1154         struct storvsc_cmd_request *request;
1155         int ret;
1156
1157         if (channel->primary_channel != NULL)
1158                 device = channel->primary_channel->device_obj;
1159         else
1160                 device = channel->device_obj;
1161
1162         stor_device = get_in_stor_device(device);
1163         if (!stor_device)
1164                 return;
1165
1166         do {
1167                 ret = vmbus_recvpacket(channel, packet,
1168                                        ALIGN((sizeof(struct vstor_packet) -
1169                                              vmscsi_size_delta), 8),
1170                                        &bytes_recvd, &request_id);
1171                 if (ret == 0 && bytes_recvd > 0) {
1172
1173                         request = (struct storvsc_cmd_request *)
1174                                         (unsigned long)request_id;
1175
1176                         if ((request == &stor_device->init_request) ||
1177                             (request == &stor_device->reset_request)) {
1178
1179                                 memcpy(&request->vstor_packet, packet,
1180                                        (sizeof(struct vstor_packet) -
1181                                         vmscsi_size_delta));
1182                                 complete(&request->wait_event);
1183                         } else {
1184                                 storvsc_on_receive(stor_device,
1185                                                 (struct vstor_packet *)packet,
1186                                                 request);
1187                         }
1188                 } else {
1189                         break;
1190                 }
1191         } while (1);
1192
1193         return;
1194 }
1195
1196 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
1197                                   bool is_fc)
1198 {
1199         struct vmstorage_channel_properties props;
1200         int ret;
1201
1202         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1203
1204         ret = vmbus_open(device->channel,
1205                          ring_size,
1206                          ring_size,
1207                          (void *)&props,
1208                          sizeof(struct vmstorage_channel_properties),
1209                          storvsc_on_channel_callback, device->channel);
1210
1211         if (ret != 0)
1212                 return ret;
1213
1214         ret = storvsc_channel_init(device, is_fc);
1215
1216         return ret;
1217 }
1218
1219 static int storvsc_dev_remove(struct hv_device *device)
1220 {
1221         struct storvsc_device *stor_device;
1222         unsigned long flags;
1223
1224         stor_device = hv_get_drvdata(device);
1225
1226         spin_lock_irqsave(&device->channel->inbound_lock, flags);
1227         stor_device->destroy = true;
1228         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1229
1230         /*
1231          * At this point, all outbound traffic should be disable. We
1232          * only allow inbound traffic (responses) to proceed so that
1233          * outstanding requests can be completed.
1234          */
1235
1236         storvsc_wait_to_drain(stor_device);
1237
1238         /*
1239          * Since we have already drained, we don't need to busy wait
1240          * as was done in final_release_stor_device()
1241          * Note that we cannot set the ext pointer to NULL until
1242          * we have drained - to drain the outgoing packets, we need to
1243          * allow incoming packets.
1244          */
1245         spin_lock_irqsave(&device->channel->inbound_lock, flags);
1246         hv_set_drvdata(device, NULL);
1247         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1248
1249         /* Close the channel */
1250         vmbus_close(device->channel);
1251
1252         kfree(stor_device->stor_chns);
1253         kfree(stor_device);
1254         return 0;
1255 }
1256
1257 static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device,
1258                                         u16 q_num)
1259 {
1260         u16 slot = 0;
1261         u16 hash_qnum;
1262         struct cpumask alloced_mask;
1263         int num_channels, tgt_cpu;
1264
1265         if (stor_device->num_sc == 0)
1266                 return stor_device->device->channel;
1267
1268         /*
1269          * Our channel array is sparsley populated and we
1270          * initiated I/O on a processor/hw-q that does not
1271          * currently have a designated channel. Fix this.
1272          * The strategy is simple:
1273          * I. Ensure NUMA locality
1274          * II. Distribute evenly (best effort)
1275          * III. Mapping is persistent.
1276          */
1277
1278         cpumask_and(&alloced_mask, &stor_device->alloced_cpus,
1279                     cpumask_of_node(cpu_to_node(q_num)));
1280
1281         num_channels = cpumask_weight(&alloced_mask);
1282         if (num_channels == 0)
1283                 return stor_device->device->channel;
1284
1285         hash_qnum = q_num;
1286         while (hash_qnum >= num_channels)
1287                 hash_qnum -= num_channels;
1288
1289         for_each_cpu(tgt_cpu, &alloced_mask) {
1290                 if (slot == hash_qnum)
1291                         break;
1292                 slot++;
1293         }
1294
1295         stor_device->stor_chns[q_num] = stor_device->stor_chns[tgt_cpu];
1296
1297         return stor_device->stor_chns[q_num];
1298 }
1299
1300
1301 static int storvsc_do_io(struct hv_device *device,
1302                          struct storvsc_cmd_request *request, u16 q_num)
1303 {
1304         struct storvsc_device *stor_device;
1305         struct vstor_packet *vstor_packet;
1306         struct vmbus_channel *outgoing_channel;
1307         int ret = 0;
1308         struct cpumask alloced_mask;
1309         int tgt_cpu;
1310
1311         vstor_packet = &request->vstor_packet;
1312         stor_device = get_out_stor_device(device);
1313
1314         if (!stor_device)
1315                 return -ENODEV;
1316
1317
1318         request->device  = device;
1319         /*
1320          * Select an an appropriate channel to send the request out.
1321          */
1322
1323         if (stor_device->stor_chns[q_num] != NULL) {
1324                 outgoing_channel = stor_device->stor_chns[q_num];
1325                 if (outgoing_channel->target_cpu == smp_processor_id()) {
1326                         /*
1327                          * Ideally, we want to pick a different channel if
1328                          * available on the same NUMA node.
1329                          */
1330                         cpumask_and(&alloced_mask, &stor_device->alloced_cpus,
1331                                     cpumask_of_node(cpu_to_node(q_num)));
1332                         for_each_cpu(tgt_cpu, &alloced_mask) {
1333                                 if (tgt_cpu != outgoing_channel->target_cpu) {
1334                                         outgoing_channel =
1335                                         stor_device->stor_chns[tgt_cpu];
1336                                         break;
1337                                 }
1338                         }
1339                 }
1340         } else {
1341                 outgoing_channel = get_og_chn(stor_device, q_num);
1342         }
1343
1344
1345         vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1346
1347         vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) -
1348                                         vmscsi_size_delta);
1349
1350
1351         vstor_packet->vm_srb.sense_info_length = sense_buffer_size;
1352
1353
1354         vstor_packet->vm_srb.data_transfer_length =
1355         request->payload->range.len;
1356
1357         vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1358
1359         if (request->payload->range.len) {
1360
1361                 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1362                                 request->payload, request->payload_sz,
1363                                 vstor_packet,
1364                                 (sizeof(struct vstor_packet) -
1365                                 vmscsi_size_delta),
1366                                 (unsigned long)request);
1367         } else {
1368                 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1369                                (sizeof(struct vstor_packet) -
1370                                 vmscsi_size_delta),
1371                                (unsigned long)request,
1372                                VM_PKT_DATA_INBAND,
1373                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1374         }
1375
1376         if (ret != 0)
1377                 return ret;
1378
1379         atomic_inc(&stor_device->num_outstanding_req);
1380
1381         return ret;
1382 }
1383
1384 static int storvsc_device_alloc(struct scsi_device *sdevice)
1385 {
1386         /*
1387          * Set blist flag to permit the reading of the VPD pages even when
1388          * the target may claim SPC-2 compliance. MSFT targets currently
1389          * claim SPC-2 compliance while they implement post SPC-2 features.
1390          * With this flag we can correctly handle WRITE_SAME_16 issues.
1391          *
1392          * Hypervisor reports SCSI_UNKNOWN type for DVD ROM device but
1393          * still supports REPORT LUN.
1394          */
1395         sdevice->sdev_bflags = BLIST_REPORTLUN2 | BLIST_TRY_VPD_PAGES;
1396
1397         return 0;
1398 }
1399
1400 static int storvsc_device_configure(struct scsi_device *sdevice)
1401 {
1402
1403         blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
1404
1405         blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1406
1407         /* Ensure there are no gaps in presented sgls */
1408         blk_queue_virt_boundary(sdevice->request_queue, PAGE_SIZE - 1);
1409
1410         sdevice->no_write_same = 1;
1411
1412         /*
1413          * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1414          * if the device is a MSFT virtual device.  If the host is
1415          * WIN10 or newer, allow write_same.
1416          */
1417         if (!strncmp(sdevice->vendor, "Msft", 4)) {
1418                 switch (vmstor_proto_version) {
1419                 case VMSTOR_PROTO_VERSION_WIN8:
1420                 case VMSTOR_PROTO_VERSION_WIN8_1:
1421                         sdevice->scsi_level = SCSI_SPC_3;
1422                         break;
1423                 }
1424
1425                 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1426                         sdevice->no_write_same = 0;
1427         }
1428
1429         return 0;
1430 }
1431
1432 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1433                            sector_t capacity, int *info)
1434 {
1435         sector_t nsect = capacity;
1436         sector_t cylinders = nsect;
1437         int heads, sectors_pt;
1438
1439         /*
1440          * We are making up these values; let us keep it simple.
1441          */
1442         heads = 0xff;
1443         sectors_pt = 0x3f;      /* Sectors per track */
1444         sector_div(cylinders, heads * sectors_pt);
1445         if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1446                 cylinders = 0xffff;
1447
1448         info[0] = heads;
1449         info[1] = sectors_pt;
1450         info[2] = (int)cylinders;
1451
1452         return 0;
1453 }
1454
1455 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1456 {
1457         struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1458         struct hv_device *device = host_dev->dev;
1459
1460         struct storvsc_device *stor_device;
1461         struct storvsc_cmd_request *request;
1462         struct vstor_packet *vstor_packet;
1463         int ret, t;
1464
1465
1466         stor_device = get_out_stor_device(device);
1467         if (!stor_device)
1468                 return FAILED;
1469
1470         request = &stor_device->reset_request;
1471         vstor_packet = &request->vstor_packet;
1472
1473         init_completion(&request->wait_event);
1474
1475         vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1476         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1477         vstor_packet->vm_srb.path_id = stor_device->path_id;
1478
1479         ret = vmbus_sendpacket(device->channel, vstor_packet,
1480                                (sizeof(struct vstor_packet) -
1481                                 vmscsi_size_delta),
1482                                (unsigned long)&stor_device->reset_request,
1483                                VM_PKT_DATA_INBAND,
1484                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1485         if (ret != 0)
1486                 return FAILED;
1487
1488         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1489         if (t == 0)
1490                 return TIMEOUT_ERROR;
1491
1492
1493         /*
1494          * At this point, all outstanding requests in the adapter
1495          * should have been flushed out and return to us
1496          * There is a potential race here where the host may be in
1497          * the process of responding when we return from here.
1498          * Just wait for all in-transit packets to be accounted for
1499          * before we return from here.
1500          */
1501         storvsc_wait_to_drain(stor_device);
1502
1503         return SUCCESS;
1504 }
1505
1506 /*
1507  * The host guarantees to respond to each command, although I/O latencies might
1508  * be unbounded on Azure.  Reset the timer unconditionally to give the host a
1509  * chance to perform EH.
1510  */
1511 static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1512 {
1513         return BLK_EH_RESET_TIMER;
1514 }
1515
1516 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1517 {
1518         bool allowed = true;
1519         u8 scsi_op = scmnd->cmnd[0];
1520
1521         switch (scsi_op) {
1522         /* the host does not handle WRITE_SAME, log accident usage */
1523         case WRITE_SAME:
1524         /*
1525          * smartd sends this command and the host does not handle
1526          * this. So, don't send it.
1527          */
1528         case SET_WINDOW:
1529                 scmnd->result = ILLEGAL_REQUEST << 16;
1530                 allowed = false;
1531                 break;
1532         default:
1533                 break;
1534         }
1535         return allowed;
1536 }
1537
1538 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1539 {
1540         int ret;
1541         struct hv_host_device *host_dev = shost_priv(host);
1542         struct hv_device *dev = host_dev->dev;
1543         struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1544         int i;
1545         struct scatterlist *sgl;
1546         unsigned int sg_count = 0;
1547         struct vmscsi_request *vm_srb;
1548         struct scatterlist *cur_sgl;
1549         struct vmbus_packet_mpb_array  *payload;
1550         u32 payload_sz;
1551         u32 length;
1552
1553         if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1554                 /*
1555                  * On legacy hosts filter unimplemented commands.
1556                  * Future hosts are expected to correctly handle
1557                  * unsupported commands. Furthermore, it is
1558                  * possible that some of the currently
1559                  * unsupported commands maybe supported in
1560                  * future versions of the host.
1561                  */
1562                 if (!storvsc_scsi_cmd_ok(scmnd)) {
1563                         scmnd->scsi_done(scmnd);
1564                         return 0;
1565                 }
1566         }
1567
1568         /* Setup the cmd request */
1569         cmd_request->cmd = scmnd;
1570
1571         vm_srb = &cmd_request->vstor_packet.vm_srb;
1572         vm_srb->win8_extension.time_out_value = 60;
1573
1574         vm_srb->win8_extension.srb_flags |=
1575                 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1576
1577         if (scmnd->device->tagged_supported) {
1578                 vm_srb->win8_extension.srb_flags |=
1579                 (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
1580                 vm_srb->win8_extension.queue_tag = SP_UNTAGGED;
1581                 vm_srb->win8_extension.queue_action = SRB_SIMPLE_TAG_REQUEST;
1582         }
1583
1584         /* Build the SRB */
1585         switch (scmnd->sc_data_direction) {
1586         case DMA_TO_DEVICE:
1587                 vm_srb->data_in = WRITE_TYPE;
1588                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_OUT;
1589                 break;
1590         case DMA_FROM_DEVICE:
1591                 vm_srb->data_in = READ_TYPE;
1592                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_IN;
1593                 break;
1594         case DMA_NONE:
1595                 vm_srb->data_in = UNKNOWN_TYPE;
1596                 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1597                 break;
1598         default:
1599                 /*
1600                  * This is DMA_BIDIRECTIONAL or something else we are never
1601                  * supposed to see here.
1602                  */
1603                 WARN(1, "Unexpected data direction: %d\n",
1604                      scmnd->sc_data_direction);
1605                 return -EINVAL;
1606         }
1607
1608
1609         vm_srb->port_number = host_dev->port;
1610         vm_srb->path_id = scmnd->device->channel;
1611         vm_srb->target_id = scmnd->device->id;
1612         vm_srb->lun = scmnd->device->lun;
1613
1614         vm_srb->cdb_length = scmnd->cmd_len;
1615
1616         memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1617
1618         sgl = (struct scatterlist *)scsi_sglist(scmnd);
1619         sg_count = scsi_sg_count(scmnd);
1620
1621         length = scsi_bufflen(scmnd);
1622         payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1623         payload_sz = sizeof(cmd_request->mpb);
1624
1625         if (sg_count) {
1626                 if (sg_count > MAX_PAGE_BUFFER_COUNT) {
1627
1628                         payload_sz = (sg_count * sizeof(u64) +
1629                                       sizeof(struct vmbus_packet_mpb_array));
1630                         payload = kzalloc(payload_sz, GFP_ATOMIC);
1631                         if (!payload)
1632                                 return SCSI_MLQUEUE_DEVICE_BUSY;
1633                 }
1634
1635                 payload->range.len = length;
1636                 payload->range.offset = sgl[0].offset;
1637
1638                 cur_sgl = sgl;
1639                 for (i = 0; i < sg_count; i++) {
1640                         payload->range.pfn_array[i] =
1641                                 page_to_pfn(sg_page((cur_sgl)));
1642                         cur_sgl = sg_next(cur_sgl);
1643                 }
1644         }
1645
1646         cmd_request->payload = payload;
1647         cmd_request->payload_sz = payload_sz;
1648
1649         /* Invokes the vsc to start an IO */
1650         ret = storvsc_do_io(dev, cmd_request, get_cpu());
1651         put_cpu();
1652
1653         if (ret == -EAGAIN) {
1654                 /* no more space */
1655                 return SCSI_MLQUEUE_DEVICE_BUSY;
1656         }
1657
1658         return 0;
1659 }
1660
1661 static struct scsi_host_template scsi_driver = {
1662         .module =               THIS_MODULE,
1663         .name =                 "storvsc_host_t",
1664         .cmd_size =             sizeof(struct storvsc_cmd_request),
1665         .bios_param =           storvsc_get_chs,
1666         .queuecommand =         storvsc_queuecommand,
1667         .eh_host_reset_handler =        storvsc_host_reset_handler,
1668         .proc_name =            "storvsc_host",
1669         .eh_timed_out =         storvsc_eh_timed_out,
1670         .slave_alloc =          storvsc_device_alloc,
1671         .slave_configure =      storvsc_device_configure,
1672         .cmd_per_lun =          255,
1673         .this_id =              -1,
1674         .use_clustering =       ENABLE_CLUSTERING,
1675         /* Make sure we dont get a sg segment crosses a page boundary */
1676         .dma_boundary =         PAGE_SIZE-1,
1677         .no_write_same =        1,
1678         .track_queue_depth =    1,
1679 };
1680
1681 enum {
1682         SCSI_GUID,
1683         IDE_GUID,
1684         SFC_GUID,
1685 };
1686
1687 static const struct hv_vmbus_device_id id_table[] = {
1688         /* SCSI guid */
1689         { HV_SCSI_GUID,
1690           .driver_data = SCSI_GUID
1691         },
1692         /* IDE guid */
1693         { HV_IDE_GUID,
1694           .driver_data = IDE_GUID
1695         },
1696         /* Fibre Channel GUID */
1697         {
1698           HV_SYNTHFC_GUID,
1699           .driver_data = SFC_GUID
1700         },
1701         { },
1702 };
1703
1704 MODULE_DEVICE_TABLE(vmbus, id_table);
1705
1706 static int storvsc_probe(struct hv_device *device,
1707                         const struct hv_vmbus_device_id *dev_id)
1708 {
1709         int ret;
1710         int num_cpus = num_online_cpus();
1711         struct Scsi_Host *host;
1712         struct hv_host_device *host_dev;
1713         bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1714         bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
1715         int target = 0;
1716         struct storvsc_device *stor_device;
1717         int max_luns_per_target;
1718         int max_targets;
1719         int max_channels;
1720         int max_sub_channels = 0;
1721
1722         /*
1723          * Based on the windows host we are running on,
1724          * set state to properly communicate with the host.
1725          */
1726
1727         if (vmbus_proto_version < VERSION_WIN8) {
1728                 max_luns_per_target = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1729                 max_targets = STORVSC_IDE_MAX_TARGETS;
1730                 max_channels = STORVSC_IDE_MAX_CHANNELS;
1731         } else {
1732                 max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET;
1733                 max_targets = STORVSC_MAX_TARGETS;
1734                 max_channels = STORVSC_MAX_CHANNELS;
1735                 /*
1736                  * On Windows8 and above, we support sub-channels for storage.
1737                  * The number of sub-channels offerred is based on the number of
1738                  * VCPUs in the guest.
1739                  */
1740                 max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel);
1741         }
1742
1743         scsi_driver.can_queue = (max_outstanding_req_per_channel *
1744                                  (max_sub_channels + 1));
1745
1746         host = scsi_host_alloc(&scsi_driver,
1747                                sizeof(struct hv_host_device));
1748         if (!host)
1749                 return -ENOMEM;
1750
1751         host_dev = shost_priv(host);
1752         memset(host_dev, 0, sizeof(struct hv_host_device));
1753
1754         host_dev->port = host->host_no;
1755         host_dev->dev = device;
1756
1757
1758         stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
1759         if (!stor_device) {
1760                 ret = -ENOMEM;
1761                 goto err_out0;
1762         }
1763
1764         stor_device->destroy = false;
1765         stor_device->open_sub_channel = false;
1766         init_waitqueue_head(&stor_device->waiting_to_drain);
1767         stor_device->device = device;
1768         stor_device->host = host;
1769         hv_set_drvdata(device, stor_device);
1770
1771         stor_device->port_number = host->host_no;
1772         ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size, is_fc);
1773         if (ret)
1774                 goto err_out1;
1775
1776         host_dev->path = stor_device->path_id;
1777         host_dev->target = stor_device->target_id;
1778
1779         switch (dev_id->driver_data) {
1780         case SFC_GUID:
1781                 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
1782                 host->max_id = STORVSC_FC_MAX_TARGETS;
1783                 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
1784 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1785                 host->transportt = fc_transport_template;
1786 #endif
1787                 break;
1788
1789         case SCSI_GUID:
1790                 host->max_lun = max_luns_per_target;
1791                 host->max_id = max_targets;
1792                 host->max_channel = max_channels - 1;
1793                 break;
1794
1795         default:
1796                 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1797                 host->max_id = STORVSC_IDE_MAX_TARGETS;
1798                 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
1799                 break;
1800         }
1801         /* max cmd length */
1802         host->max_cmd_len = STORVSC_MAX_CMD_LEN;
1803
1804         /*
1805          * set the table size based on the info we got
1806          * from the host.
1807          */
1808         host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
1809         /*
1810          * Set the number of HW queues we are supporting.
1811          */
1812         if (stor_device->num_sc != 0)
1813                 host->nr_hw_queues = stor_device->num_sc + 1;
1814
1815         /* Register the HBA and start the scsi bus scan */
1816         ret = scsi_add_host(host, &device->device);
1817         if (ret != 0)
1818                 goto err_out2;
1819
1820         if (!dev_is_ide) {
1821                 scsi_scan_host(host);
1822         } else {
1823                 target = (device->dev_instance.b[5] << 8 |
1824                          device->dev_instance.b[4]);
1825                 ret = scsi_add_device(host, 0, target, 0);
1826                 if (ret) {
1827                         scsi_remove_host(host);
1828                         goto err_out2;
1829                 }
1830         }
1831 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1832         if (host->transportt == fc_transport_template) {
1833                 fc_host_node_name(host) = stor_device->node_name;
1834                 fc_host_port_name(host) = stor_device->port_name;
1835         }
1836 #endif
1837         return 0;
1838
1839 err_out2:
1840         /*
1841          * Once we have connected with the host, we would need to
1842          * to invoke storvsc_dev_remove() to rollback this state and
1843          * this call also frees up the stor_device; hence the jump around
1844          * err_out1 label.
1845          */
1846         storvsc_dev_remove(device);
1847         goto err_out0;
1848
1849 err_out1:
1850         kfree(stor_device->stor_chns);
1851         kfree(stor_device);
1852
1853 err_out0:
1854         scsi_host_put(host);
1855         return ret;
1856 }
1857
1858 static int storvsc_remove(struct hv_device *dev)
1859 {
1860         struct storvsc_device *stor_device = hv_get_drvdata(dev);
1861         struct Scsi_Host *host = stor_device->host;
1862
1863 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1864         if (host->transportt == fc_transport_template)
1865                 fc_remove_host(host);
1866 #endif
1867         scsi_remove_host(host);
1868         storvsc_dev_remove(dev);
1869         scsi_host_put(host);
1870
1871         return 0;
1872 }
1873
1874 static struct hv_driver storvsc_drv = {
1875         .name = KBUILD_MODNAME,
1876         .id_table = id_table,
1877         .probe = storvsc_probe,
1878         .remove = storvsc_remove,
1879 };
1880
1881 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1882 static struct fc_function_template fc_transport_functions = {
1883         .show_host_node_name = 1,
1884         .show_host_port_name = 1,
1885 };
1886 #endif
1887
1888 static int __init storvsc_drv_init(void)
1889 {
1890         int ret;
1891
1892         /*
1893          * Divide the ring buffer data size (which is 1 page less
1894          * than the ring buffer size since that page is reserved for
1895          * the ring buffer indices) by the max request size (which is
1896          * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
1897          */
1898         max_outstanding_req_per_channel =
1899                 ((storvsc_ringbuffer_size - PAGE_SIZE) /
1900                 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
1901                 sizeof(struct vstor_packet) + sizeof(u64) -
1902                 vmscsi_size_delta,
1903                 sizeof(u64)));
1904
1905 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1906         fc_transport_template = fc_attach_transport(&fc_transport_functions);
1907         if (!fc_transport_template)
1908                 return -ENODEV;
1909 #endif
1910
1911         ret = vmbus_driver_register(&storvsc_drv);
1912
1913 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1914         if (ret)
1915                 fc_release_transport(fc_transport_template);
1916 #endif
1917
1918         return ret;
1919 }
1920
1921 static void __exit storvsc_drv_exit(void)
1922 {
1923         vmbus_driver_unregister(&storvsc_drv);
1924 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1925         fc_release_transport(fc_transport_template);
1926 #endif
1927 }
1928
1929 MODULE_LICENSE("GPL");
1930 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
1931 module_init(storvsc_drv_init);
1932 module_exit(storvsc_drv_exit);