drivers/target/target_core_pscsi.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*******************************************************************************
   3  * Filename:  target_core_pscsi.c
   4  *
   5  * This file contains the generic target mode <-> Linux SCSI subsystem plugin.
   6  *
   7  * (c) Copyright 2003-2013 Datera, Inc.
   8  *
   9  * Nicholas A. Bellinger <nab@kernel.org>
  10  *
  11  ******************************************************************************/
  12
  13 #include <linux/string.h>
  14 #include <linux/parser.h>
  15 #include <linux/timer.h>
  16 #include <linux/blkdev.h>
  17 #include <linux/blk_types.h>
  18 #include <linux/slab.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/cdrom.h>
  21 #include <linux/ratelimit.h>
  22 #include <linux/module.h>
  23 #include <asm/unaligned.h>
  24
  25 #include <scsi/scsi_device.h>
  26 #include <scsi/scsi_host.h>
  27 #include <scsi/scsi_tcq.h>
  28
  29 #include <target/target_core_base.h>
  30 #include <target/target_core_backend.h>
  31
  32 #include "target_core_alua.h"
  33 #include "target_core_internal.h"
  34 #include "target_core_pscsi.h"
  35
  36 static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
  37 {
  38         return container_of(dev, struct pscsi_dev_virt, dev);
  39 }
  40
  41 static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
  42 static enum rq_end_io_ret pscsi_req_done(struct request *, blk_status_t);
  43
  44 /*      pscsi_attach_hba():
  45  *
  46  *      pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
  47  *      from the passed SCSI Host ID.
  48  */
  49 static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
  50 {
  51         struct pscsi_hba_virt *phv;
  52
  53         phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
  54         if (!phv) {
  55                 pr_err("Unable to allocate struct pscsi_hba_virt\n");
  56                 return -ENOMEM;
  57         }
  58         phv->phv_host_id = host_id;
  59         phv->phv_mode = PHV_VIRTUAL_HOST_ID;
  60
  61         hba->hba_ptr = phv;
  62
  63         pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
  64                 " Generic Target Core Stack %s\n", hba->hba_id,
  65                 PSCSI_VERSION, TARGET_CORE_VERSION);
  66         pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
  67                hba->hba_id);
  68
  69         return 0;
  70 }
  71
  72 static void pscsi_detach_hba(struct se_hba *hba)
  73 {
  74         struct pscsi_hba_virt *phv = hba->hba_ptr;
  75         struct Scsi_Host *scsi_host = phv->phv_lld_host;
  76
  77         if (scsi_host) {
  78                 scsi_host_put(scsi_host);
  79
  80                 pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
  81                         " Generic Target Core\n", hba->hba_id,
  82                         (scsi_host->hostt->name) ? (scsi_host->hostt->name) :
  83                         "Unknown");
  84         } else
  85                 pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
  86                         " from Generic Target Core\n", hba->hba_id);
  87
  88         kfree(phv);
  89         hba->hba_ptr = NULL;
  90 }
  91
  92 static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
  93 {
  94         struct pscsi_hba_virt *phv = hba->hba_ptr;
  95         struct Scsi_Host *sh = phv->phv_lld_host;
  96         /*
  97          * Release the struct Scsi_Host
  98          */
  99         if (!mode_flag) {
 100                 if (!sh)
 101                         return 0;
 102
 103                 phv->phv_lld_host = NULL;
 104                 phv->phv_mode = PHV_VIRTUAL_HOST_ID;
 105
 106                 pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
 107                         " %s\n", hba->hba_id, (sh->hostt->name) ?
 108                         (sh->hostt->name) : "Unknown");
 109
 110                 scsi_host_put(sh);
 111                 return 0;
 112         }
 113         /*
 114          * Otherwise, locate struct Scsi_Host from the original passed
 115          * pSCSI Host ID and enable for phba mode
 116          */
 117         sh = scsi_host_lookup(phv->phv_host_id);
 118         if (!sh) {
 119                 pr_err("pSCSI: Unable to locate SCSI Host for"
 120                         " phv_host_id: %d\n", phv->phv_host_id);
 121                 return -EINVAL;
 122         }
 123
 124         phv->phv_lld_host = sh;
 125         phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
 126
 127         pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
 128                 hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
 129
 130         return 1;
 131 }
 132
 133 static void pscsi_tape_read_blocksize(struct se_device *dev,
 134                 struct scsi_device *sdev)
 135 {
 136         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 137         int ret;
 138
 139         buf = kzalloc(12, GFP_KERNEL);
 140         if (!buf)
 141                 goto out_free;
 142
 143         memset(cdb, 0, MAX_COMMAND_SIZE);
 144         cdb[0] = MODE_SENSE;
 145         cdb[4] = 0x0c; /* 12 bytes */
 146
 147         ret = scsi_execute_cmd(sdev, cdb, REQ_OP_DRV_IN, buf, 12, HZ, 1, NULL);
 148         if (ret)
 149                 goto out_free;
 150
 151         /*
 152          * If MODE_SENSE still returns zero, set the default value to 1024.
 153          */
 154         sdev->sector_size = get_unaligned_be24(&buf[9]);
 155 out_free:
 156         if (!sdev->sector_size)
 157                 sdev->sector_size = 1024;
 158
 159         kfree(buf);
 160 }
 161
 162 static void
 163 pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
 164 {
 165         if (sdev->inquiry_len < INQUIRY_LEN)
 166                 return;
 167         /*
 168          * Use sdev->inquiry data from drivers/scsi/scsi_scan.c:scsi_add_lun()
 169          */
 170         BUILD_BUG_ON(sizeof(wwn->vendor) != INQUIRY_VENDOR_LEN + 1);
 171         snprintf(wwn->vendor, sizeof(wwn->vendor),
 172                  "%." __stringify(INQUIRY_VENDOR_LEN) "s", sdev->vendor);
 173         BUILD_BUG_ON(sizeof(wwn->model) != INQUIRY_MODEL_LEN + 1);
 174         snprintf(wwn->model, sizeof(wwn->model),
 175                  "%." __stringify(INQUIRY_MODEL_LEN) "s", sdev->model);
 176         BUILD_BUG_ON(sizeof(wwn->revision) != INQUIRY_REVISION_LEN + 1);
 177         snprintf(wwn->revision, sizeof(wwn->revision),
 178                  "%." __stringify(INQUIRY_REVISION_LEN) "s", sdev->rev);
 179 }
 180
 181 static int
 182 pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
 183 {
 184         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 185         int ret;
 186
 187         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 188         if (!buf)
 189                 return -ENOMEM;
 190
 191         memset(cdb, 0, MAX_COMMAND_SIZE);
 192         cdb[0] = INQUIRY;
 193         cdb[1] = 0x01; /* Query VPD */
 194         cdb[2] = 0x80; /* Unit Serial Number */
 195         put_unaligned_be16(INQUIRY_VPD_SERIAL_LEN, &cdb[3]);
 196
 197         ret = scsi_execute_cmd(sdev, cdb, REQ_OP_DRV_IN, buf,
 198                                INQUIRY_VPD_SERIAL_LEN, HZ, 1, NULL);
 199         if (ret)
 200                 goto out_free;
 201
 202         snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
 203
 204         wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
 205
 206         kfree(buf);
 207         return 0;
 208
 209 out_free:
 210         kfree(buf);
 211         return -EPERM;
 212 }
 213
 214 static void
 215 pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
 216                 struct t10_wwn *wwn)
 217 {
 218         unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
 219         int ident_len, page_len, off = 4, ret;
 220         struct t10_vpd *vpd;
 221
 222         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 223         if (!buf)
 224                 return;
 225
 226         memset(cdb, 0, MAX_COMMAND_SIZE);
 227         cdb[0] = INQUIRY;
 228         cdb[1] = 0x01; /* Query VPD */
 229         cdb[2] = 0x83; /* Device Identifier */
 230         put_unaligned_be16(INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, &cdb[3]);
 231
 232         ret = scsi_execute_cmd(sdev, cdb, REQ_OP_DRV_IN, buf,
 233                                INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, HZ, 1, NULL);
 234         if (ret)
 235                 goto out;
 236
 237         page_len = get_unaligned_be16(&buf[2]);
 238         while (page_len > 0) {
 239                 /* Grab a pointer to the Identification descriptor */
 240                 page_83 = &buf[off];
 241                 ident_len = page_83[3];
 242                 if (!ident_len) {
 243                         pr_err("page_83[3]: identifier"
 244                                         " length zero!\n");
 245                         break;
 246                 }
 247                 pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
 248
 249                 vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
 250                 if (!vpd) {
 251                         pr_err("Unable to allocate memory for"
 252                                         " struct t10_vpd\n");
 253                         goto out;
 254                 }
 255                 INIT_LIST_HEAD(&vpd->vpd_list);
 256
 257                 transport_set_vpd_proto_id(vpd, page_83);
 258                 transport_set_vpd_assoc(vpd, page_83);
 259
 260                 if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
 261                         off += (ident_len + 4);
 262                         page_len -= (ident_len + 4);
 263                         kfree(vpd);
 264                         continue;
 265                 }
 266                 if (transport_set_vpd_ident(vpd, page_83) < 0) {
 267                         off += (ident_len + 4);
 268                         page_len -= (ident_len + 4);
 269                         kfree(vpd);
 270                         continue;
 271                 }
 272
 273                 list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
 274                 off += (ident_len + 4);
 275                 page_len -= (ident_len + 4);
 276         }
 277
 278 out:
 279         kfree(buf);
 280 }
 281
 282 static int pscsi_add_device_to_list(struct se_device *dev,
 283                 struct scsi_device *sd)
 284 {
 285         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 286         struct request_queue *q = sd->request_queue;
 287
 288         pdv->pdv_sd = sd;
 289
 290         if (!sd->queue_depth) {
 291                 sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
 292
 293                 pr_err("Set broken SCSI Device %d:%d:%llu"
 294                         " queue_depth to %d\n", sd->channel, sd->id,
 295                                 sd->lun, sd->queue_depth);
 296         }
 297
 298         dev->dev_attrib.hw_block_size =
 299                 min_not_zero((int)sd->sector_size, 512);
 300         dev->dev_attrib.hw_max_sectors =
 301                 min_not_zero(sd->host->max_sectors, queue_max_hw_sectors(q));
 302         dev->dev_attrib.hw_queue_depth = sd->queue_depth;
 303
 304         /*
 305          * Setup our standard INQUIRY info into se_dev->t10_wwn
 306          */
 307         pscsi_set_inquiry_info(sd, &dev->t10_wwn);
 308
 309         /*
 310          * Locate VPD WWN Information used for various purposes within
 311          * the Storage Engine.
 312          */
 313         if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
 314                 /*
 315                  * If VPD Unit Serial returned GOOD status, try
 316                  * VPD Device Identification page (0x83).
 317                  */
 318                 pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
 319         }
 320
 321         /*
 322          * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
 323          */
 324         if (sd->type == TYPE_TAPE) {
 325                 pscsi_tape_read_blocksize(dev, sd);
 326                 dev->dev_attrib.hw_block_size = sd->sector_size;
 327         }
 328         return 0;
 329 }
 330
 331 static struct se_device *pscsi_alloc_device(struct se_hba *hba,
 332                 const char *name)
 333 {
 334         struct pscsi_dev_virt *pdv;
 335
 336         pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
 337         if (!pdv) {
 338                 pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
 339                 return NULL;
 340         }
 341
 342         pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
 343         return &pdv->dev;
 344 }
 345
 346 /*
 347  * Called with struct Scsi_Host->host_lock called.
 348  */
 349 static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
 350         __releases(sh->host_lock)
 351 {
 352         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 353         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 354         struct Scsi_Host *sh = sd->host;
 355         struct block_device *bd;
 356         int ret;
 357
 358         if (scsi_device_get(sd)) {
 359                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 360                         sh->host_no, sd->channel, sd->id, sd->lun);
 361                 spin_unlock_irq(sh->host_lock);
 362                 return -EIO;
 363         }
 364         spin_unlock_irq(sh->host_lock);
 365         /*
 366          * Claim exclusive struct block_device access to struct scsi_device
 367          * for TYPE_DISK and TYPE_ZBC using supplied udev_path
 368          */
 369         bd = blkdev_get_by_path(dev->udev_path,
 370                                 FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
 371         if (IS_ERR(bd)) {
 372                 pr_err("pSCSI: blkdev_get_by_path() failed\n");
 373                 scsi_device_put(sd);
 374                 return PTR_ERR(bd);
 375         }
 376         pdv->pdv_bd = bd;
 377
 378         ret = pscsi_add_device_to_list(dev, sd);
 379         if (ret) {
 380                 blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 381                 scsi_device_put(sd);
 382                 return ret;
 383         }
 384
 385         pr_debug("CORE_PSCSI[%d] - Added TYPE_%s for %d:%d:%d:%llu\n",
 386                 phv->phv_host_id, sd->type == TYPE_DISK ? "DISK" : "ZBC",
 387                 sh->host_no, sd->channel, sd->id, sd->lun);
 388         return 0;
 389 }
 390
 391 /*
 392  * Called with struct Scsi_Host->host_lock called.
 393  */
 394 static int pscsi_create_type_nondisk(struct se_device *dev, struct scsi_device *sd)
 395         __releases(sh->host_lock)
 396 {
 397         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 398         struct Scsi_Host *sh = sd->host;
 399         int ret;
 400
 401         if (scsi_device_get(sd)) {
 402                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 403                         sh->host_no, sd->channel, sd->id, sd->lun);
 404                 spin_unlock_irq(sh->host_lock);
 405                 return -EIO;
 406         }
 407         spin_unlock_irq(sh->host_lock);
 408
 409         ret = pscsi_add_device_to_list(dev, sd);
 410         if (ret) {
 411                 scsi_device_put(sd);
 412                 return ret;
 413         }
 414         pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
 415                 phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
 416                 sd->channel, sd->id, sd->lun);
 417
 418         return 0;
 419 }
 420
 421 static int pscsi_configure_device(struct se_device *dev)
 422 {
 423         struct se_hba *hba = dev->se_hba;
 424         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 425         struct scsi_device *sd;
 426         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 427         struct Scsi_Host *sh = phv->phv_lld_host;
 428         int legacy_mode_enable = 0;
 429         int ret;
 430
 431         if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
 432             !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
 433             !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
 434                 pr_err("Missing scsi_channel_id=, scsi_target_id= and"
 435                         " scsi_lun_id= parameters\n");
 436                 return -EINVAL;
 437         }
 438
 439         /*
 440          * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
 441          * struct Scsi_Host we will need to bring the TCM/pSCSI object online
 442          */
 443         if (!sh) {
 444                 if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 445                         pr_err("pSCSI: Unable to locate struct"
 446                                 " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
 447                         return -ENODEV;
 448                 }
 449                 /*
 450                  * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
 451                  * reference, we enforce that udev_path has been set
 452                  */
 453                 if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
 454                         pr_err("pSCSI: udev_path attribute has not"
 455                                 " been set before ENABLE=1\n");
 456                         return -EINVAL;
 457                 }
 458                 /*
 459                  * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
 460                  * use the original TCM hba ID to reference Linux/SCSI Host No
 461                  * and enable for PHV_LLD_SCSI_HOST_NO mode.
 462                  */
 463                 if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
 464                         if (hba->dev_count) {
 465                                 pr_err("pSCSI: Unable to set hba_mode"
 466                                         " with active devices\n");
 467                                 return -EEXIST;
 468                         }
 469
 470                         if (pscsi_pmode_enable_hba(hba, 1) != 1)
 471                                 return -ENODEV;
 472
 473                         legacy_mode_enable = 1;
 474                         hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
 475                         sh = phv->phv_lld_host;
 476                 } else {
 477                         sh = scsi_host_lookup(pdv->pdv_host_id);
 478                         if (!sh) {
 479                                 pr_err("pSCSI: Unable to locate"
 480                                         " pdv_host_id: %d\n", pdv->pdv_host_id);
 481                                 return -EINVAL;
 482                         }
 483                         pdv->pdv_lld_host = sh;
 484                 }
 485         } else {
 486                 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
 487                         pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
 488                                 " struct Scsi_Host exists\n");
 489                         return -EEXIST;
 490                 }
 491         }
 492
 493         spin_lock_irq(sh->host_lock);
 494         list_for_each_entry(sd, &sh->__devices, siblings) {
 495                 if ((pdv->pdv_channel_id != sd->channel) ||
 496                     (pdv->pdv_target_id != sd->id) ||
 497                     (pdv->pdv_lun_id != sd->lun))
 498                         continue;
 499                 /*
 500                  * Functions will release the held struct scsi_host->host_lock
 501                  * before calling pscsi_add_device_to_list() to register
 502                  * struct scsi_device with target_core_mod.
 503                  */
 504                 switch (sd->type) {
 505                 case TYPE_DISK:
 506                 case TYPE_ZBC:
 507                         ret = pscsi_create_type_disk(dev, sd);
 508                         break;
 509                 default:
 510                         ret = pscsi_create_type_nondisk(dev, sd);
 511                         break;
 512                 }
 513
 514                 if (ret) {
 515                         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 516                                 scsi_host_put(sh);
 517                         else if (legacy_mode_enable) {
 518                                 pscsi_pmode_enable_hba(hba, 0);
 519                                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 520                         }
 521                         pdv->pdv_sd = NULL;
 522                         return ret;
 523                 }
 524                 return 0;
 525         }
 526         spin_unlock_irq(sh->host_lock);
 527
 528         pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
 529                 pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
 530
 531         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 532                 scsi_host_put(sh);
 533         else if (legacy_mode_enable) {
 534                 pscsi_pmode_enable_hba(hba, 0);
 535                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 536         }
 537
 538         return -ENODEV;
 539 }
 540
 541 static void pscsi_dev_call_rcu(struct rcu_head *p)
 542 {
 543         struct se_device *dev = container_of(p, struct se_device, rcu_head);
 544         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 545
 546         kfree(pdv);
 547 }
 548
 549 static void pscsi_free_device(struct se_device *dev)
 550 {
 551         call_rcu(&dev->rcu_head, pscsi_dev_call_rcu);
 552 }
 553
 554 static void pscsi_destroy_device(struct se_device *dev)
 555 {
 556         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 557         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 558         struct scsi_device *sd = pdv->pdv_sd;
 559
 560         if (sd) {
 561                 /*
 562                  * Release exclusive pSCSI internal struct block_device claim for
 563                  * struct scsi_device with TYPE_DISK or TYPE_ZBC
 564                  * from pscsi_create_type_disk()
 565                  */
 566                 if ((sd->type == TYPE_DISK || sd->type == TYPE_ZBC) &&
 567                     pdv->pdv_bd) {
 568                         blkdev_put(pdv->pdv_bd,
 569                                    FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 570                         pdv->pdv_bd = NULL;
 571                 }
 572                 /*
 573                  * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
 574                  * to struct Scsi_Host now.
 575                  */
 576                 if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
 577                     (phv->phv_lld_host != NULL))
 578                         scsi_host_put(phv->phv_lld_host);
 579                 else if (pdv->pdv_lld_host)
 580                         scsi_host_put(pdv->pdv_lld_host);
 581
 582                 scsi_device_put(sd);
 583
 584                 pdv->pdv_sd = NULL;
 585         }
 586 }
 587
 588 static void pscsi_complete_cmd(struct se_cmd *cmd, u8 scsi_status,
 589                                unsigned char *req_sense, int valid_data)
 590 {
 591         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 592         struct scsi_device *sd = pdv->pdv_sd;
 593         unsigned char *cdb = cmd->priv;
 594
 595         /*
 596          * Special case for REPORT_LUNs which is emulated and not passed on.
 597          */
 598         if (!cdb)
 599                 return;
 600
 601         /*
 602          * Hack to make sure that Write-Protect modepage is set if R/O mode is
 603          * forced.
 604          */
 605         if (!cmd->data_length)
 606                 goto after_mode_sense;
 607
 608         if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
 609             scsi_status == SAM_STAT_GOOD) {
 610                 bool read_only = target_lun_is_rdonly(cmd);
 611
 612                 if (read_only) {
 613                         unsigned char *buf;
 614
 615                         buf = transport_kmap_data_sg(cmd);
 616                         if (!buf) {
 617                                 ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
 618                         } else {
 619                                 if (cdb[0] == MODE_SENSE_10) {
 620                                         if (!(buf[3] & 0x80))
 621                                                 buf[3] |= 0x80;
 622                                 } else {
 623                                         if (!(buf[2] & 0x80))
 624                                                 buf[2] |= 0x80;
 625                                 }
 626
 627                                 transport_kunmap_data_sg(cmd);
 628                         }
 629                 }
 630         }
 631 after_mode_sense:
 632
 633         if (sd->type != TYPE_TAPE || !cmd->data_length)
 634                 goto after_mode_select;
 635
 636         /*
 637          * Hack to correctly obtain the initiator requested blocksize for
 638          * TYPE_TAPE.  Since this value is dependent upon each tape media,
 639          * struct scsi_device->sector_size will not contain the correct value
 640          * by default, so we go ahead and set it so
 641          * TRANSPORT(dev)->get_blockdev() returns the correct value to the
 642          * storage engine.
 643          */
 644         if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
 645              scsi_status == SAM_STAT_GOOD) {
 646                 unsigned char *buf;
 647                 u16 bdl;
 648                 u32 blocksize;
 649
 650                 buf = sg_virt(&cmd->t_data_sg[0]);
 651                 if (!buf) {
 652                         pr_err("Unable to get buf for scatterlist\n");
 653                         goto after_mode_select;
 654                 }
 655
 656                 if (cdb[0] == MODE_SELECT)
 657                         bdl = buf[3];
 658                 else
 659                         bdl = get_unaligned_be16(&buf[6]);
 660
 661                 if (!bdl)
 662                         goto after_mode_select;
 663
 664                 if (cdb[0] == MODE_SELECT)
 665                         blocksize = get_unaligned_be24(&buf[9]);
 666                 else
 667                         blocksize = get_unaligned_be24(&buf[13]);
 668
 669                 sd->sector_size = blocksize;
 670         }
 671 after_mode_select:
 672
 673         if (scsi_status == SAM_STAT_CHECK_CONDITION) {
 674                 transport_copy_sense_to_cmd(cmd, req_sense);
 675
 676                 /*
 677                  * check for TAPE device reads with
 678                  * FM/EOM/ILI set, so that we can get data
 679                  * back despite framework assumption that a
 680                  * check condition means there is no data
 681                  */
 682                 if (sd->type == TYPE_TAPE && valid_data &&
 683                     cmd->data_direction == DMA_FROM_DEVICE) {
 684                         /*
 685                          * is sense data valid, fixed format,
 686                          * and have FM, EOM, or ILI set?
 687                          */
 688                         if (req_sense[0] == 0xf0 &&     /* valid, fixed format */
 689                             req_sense[2] & 0xe0 &&      /* FM, EOM, or ILI */
 690                             (req_sense[2] & 0xf) == 0) { /* key==NO_SENSE */
 691                                 pr_debug("Tape FM/EOM/ILI status detected. Treat as normal read.\n");
 692                                 cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL;
 693                         }
 694                 }
 695         }
 696 }
 697
 698 enum {
 699         Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
 700         Opt_scsi_lun_id, Opt_err
 701 };
 702
 703 static match_table_t tokens = {
 704         {Opt_scsi_host_id, "scsi_host_id=%d"},
 705         {Opt_scsi_channel_id, "scsi_channel_id=%d"},
 706         {Opt_scsi_target_id, "scsi_target_id=%d"},
 707         {Opt_scsi_lun_id, "scsi_lun_id=%d"},
 708         {Opt_err, NULL}
 709 };
 710
 711 static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
 712                 const char *page, ssize_t count)
 713 {
 714         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 715         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 716         char *orig, *ptr, *opts;
 717         substring_t args[MAX_OPT_ARGS];
 718         int ret = 0, arg, token;
 719
 720         opts = kstrdup(page, GFP_KERNEL);
 721         if (!opts)
 722                 return -ENOMEM;
 723
 724         orig = opts;
 725
 726         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 727                 if (!*ptr)
 728                         continue;
 729
 730                 token = match_token(ptr, tokens, args);
 731                 switch (token) {
 732                 case Opt_scsi_host_id:
 733                         if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 734                                 pr_err("PSCSI[%d]: Unable to accept"
 735                                         " scsi_host_id while phv_mode =="
 736                                         " PHV_LLD_SCSI_HOST_NO\n",
 737                                         phv->phv_host_id);
 738                                 ret = -EINVAL;
 739                                 goto out;
 740                         }
 741                         ret = match_int(args, &arg);
 742                         if (ret)
 743                                 goto out;
 744                         pdv->pdv_host_id = arg;
 745                         pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
 746                                 " %d\n", phv->phv_host_id, pdv->pdv_host_id);
 747                         pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
 748                         break;
 749                 case Opt_scsi_channel_id:
 750                         ret = match_int(args, &arg);
 751                         if (ret)
 752                                 goto out;
 753                         pdv->pdv_channel_id = arg;
 754                         pr_debug("PSCSI[%d]: Referencing SCSI Channel"
 755                                 " ID: %d\n",  phv->phv_host_id,
 756                                 pdv->pdv_channel_id);
 757                         pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
 758                         break;
 759                 case Opt_scsi_target_id:
 760                         ret = match_int(args, &arg);
 761                         if (ret)
 762                                 goto out;
 763                         pdv->pdv_target_id = arg;
 764                         pr_debug("PSCSI[%d]: Referencing SCSI Target"
 765                                 " ID: %d\n", phv->phv_host_id,
 766                                 pdv->pdv_target_id);
 767                         pdv->pdv_flags |= PDF_HAS_TARGET_ID;
 768                         break;
 769                 case Opt_scsi_lun_id:
 770                         ret = match_int(args, &arg);
 771                         if (ret)
 772                                 goto out;
 773                         pdv->pdv_lun_id = arg;
 774                         pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
 775                                 " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
 776                         pdv->pdv_flags |= PDF_HAS_LUN_ID;
 777                         break;
 778                 default:
 779                         break;
 780                 }
 781         }
 782
 783 out:
 784         kfree(orig);
 785         return (!ret) ? count : ret;
 786 }
 787
 788 static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
 789 {
 790         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 791         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 792         struct scsi_device *sd = pdv->pdv_sd;
 793         unsigned char host_id[16];
 794         ssize_t bl;
 795
 796         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 797                 snprintf(host_id, 16, "%d", pdv->pdv_host_id);
 798         else
 799                 snprintf(host_id, 16, "PHBA Mode");
 800
 801         bl = sprintf(b, "SCSI Device Bus Location:"
 802                 " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
 803                 pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
 804                 host_id);
 805
 806         if (sd) {
 807                 bl += sprintf(b + bl, "        Vendor: %."
 808                         __stringify(INQUIRY_VENDOR_LEN) "s", sd->vendor);
 809                 bl += sprintf(b + bl, " Model: %."
 810                         __stringify(INQUIRY_MODEL_LEN) "s", sd->model);
 811                 bl += sprintf(b + bl, " Rev: %."
 812                         __stringify(INQUIRY_REVISION_LEN) "s\n", sd->rev);
 813         }
 814         return bl;
 815 }
 816
 817 static void pscsi_bi_endio(struct bio *bio)
 818 {
 819         bio_uninit(bio);
 820         kfree(bio);
 821 }
 822
 823 static sense_reason_t
 824 pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 825                 struct request *req)
 826 {
 827         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 828         struct bio *bio = NULL;
 829         struct page *page;
 830         struct scatterlist *sg;
 831         u32 data_len = cmd->data_length, i, len, bytes, off;
 832         int nr_pages = (cmd->data_length + sgl[0].offset +
 833                         PAGE_SIZE - 1) >> PAGE_SHIFT;
 834         int nr_vecs = 0, rc;
 835         int rw = (cmd->data_direction == DMA_TO_DEVICE);
 836
 837         BUG_ON(!cmd->data_length);
 838
 839         pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
 840
 841         for_each_sg(sgl, sg, sgl_nents, i) {
 842                 page = sg_page(sg);
 843                 off = sg->offset;
 844                 len = sg->length;
 845
 846                 pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
 847                         page, len, off);
 848
 849                 /*
 850                  * We only have one page of data in each sg element,
 851                  * we can not cross a page boundary.
 852                  */
 853                 if (off + len > PAGE_SIZE)
 854                         goto fail;
 855
 856                 if (len > 0 && data_len > 0) {
 857                         bytes = min_t(unsigned int, len, PAGE_SIZE - off);
 858                         bytes = min(bytes, data_len);
 859
 860                         if (!bio) {
 861 new_bio:
 862                                 nr_vecs = bio_max_segs(nr_pages);
 863                                 bio = bio_kmalloc(nr_vecs, GFP_KERNEL);
 864                                 if (!bio)
 865                                         goto fail;
 866                                 bio_init(bio, NULL, bio->bi_inline_vecs, nr_vecs,
 867                                          rw ? REQ_OP_WRITE : REQ_OP_READ);
 868                                 bio->bi_end_io = pscsi_bi_endio;
 869
 870                                 pr_debug("PSCSI: Allocated bio: %p,"
 871                                         " dir: %s nr_vecs: %d\n", bio,
 872                                         (rw) ? "rw" : "r", nr_vecs);
 873                         }
 874
 875                         pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
 876                                 " bio: %p page: %p len: %d off: %d\n", i, bio,
 877                                 page, len, off);
 878
 879                         rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
 880                                         bio, page, bytes, off);
 881                         pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
 882                                 bio_segments(bio), nr_vecs);
 883                         if (rc != bytes) {
 884                                 pr_debug("PSCSI: Reached bio->bi_vcnt max:"
 885                                         " %d i: %d bio: %p, allocating another"
 886                                         " bio\n", bio->bi_vcnt, i, bio);
 887
 888                                 rc = blk_rq_append_bio(req, bio);
 889                                 if (rc) {
 890                                         pr_err("pSCSI: failed to append bio\n");
 891                                         goto fail;
 892                                 }
 893
 894                                 goto new_bio;
 895                         }
 896
 897                         data_len -= bytes;
 898                 }
 899         }
 900
 901         if (bio) {
 902                 rc = blk_rq_append_bio(req, bio);
 903                 if (rc) {
 904                         pr_err("pSCSI: failed to append bio\n");
 905                         goto fail;
 906                 }
 907         }
 908
 909         return 0;
 910 fail:
 911         if (bio)
 912                 bio_put(bio);
 913         while (req->bio) {
 914                 bio = req->bio;
 915                 req->bio = bio->bi_next;
 916                 bio_put(bio);
 917         }
 918         req->biotail = NULL;
 919         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 920 }
 921
 922 static sense_reason_t
 923 pscsi_parse_cdb(struct se_cmd *cmd)
 924 {
 925         if (cmd->se_cmd_flags & SCF_BIDI)
 926                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 927
 928         return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
 929 }
 930
 931 static sense_reason_t
 932 pscsi_execute_cmd(struct se_cmd *cmd)
 933 {
 934         struct scatterlist *sgl = cmd->t_data_sg;
 935         u32 sgl_nents = cmd->t_data_nents;
 936         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 937         struct scsi_cmnd *scmd;
 938         struct request *req;
 939         sense_reason_t ret;
 940
 941         req = scsi_alloc_request(pdv->pdv_sd->request_queue,
 942                         cmd->data_direction == DMA_TO_DEVICE ?
 943                         REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
 944         if (IS_ERR(req))
 945                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 946
 947         if (sgl) {
 948                 ret = pscsi_map_sg(cmd, sgl, sgl_nents, req);
 949                 if (ret)
 950                         goto fail_put_request;
 951         }
 952
 953         req->end_io = pscsi_req_done;
 954         req->end_io_data = cmd;
 955
 956         scmd = blk_mq_rq_to_pdu(req);
 957         scmd->cmd_len = scsi_command_size(cmd->t_task_cdb);
 958         if (scmd->cmd_len > sizeof(scmd->cmnd)) {
 959                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 960                 goto fail_put_request;
 961         }
 962         memcpy(scmd->cmnd, cmd->t_task_cdb, scmd->cmd_len);
 963
 964         if (pdv->pdv_sd->type == TYPE_DISK ||
 965             pdv->pdv_sd->type == TYPE_ZBC)
 966                 req->timeout = PS_TIMEOUT_DISK;
 967         else
 968                 req->timeout = PS_TIMEOUT_OTHER;
 969         scmd->allowed = PS_RETRY;
 970
 971         cmd->priv = scmd->cmnd;
 972
 973         blk_execute_rq_nowait(req, cmd->sam_task_attr == TCM_HEAD_TAG);
 974
 975         return 0;
 976
 977 fail_put_request:
 978         blk_mq_free_request(req);
 979         return ret;
 980 }
 981
 982 /*      pscsi_get_device_type():
 983  *
 984  *
 985  */
 986 static u32 pscsi_get_device_type(struct se_device *dev)
 987 {
 988         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 989         struct scsi_device *sd = pdv->pdv_sd;
 990
 991         return (sd) ? sd->type : TYPE_NO_LUN;
 992 }
 993
 994 static sector_t pscsi_get_blocks(struct se_device *dev)
 995 {
 996         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 997
 998         if (pdv->pdv_bd)
 999                 return bdev_nr_sectors(pdv->pdv_bd);
1000         return 0;
1001 }
1002
1003 static enum rq_end_io_ret pscsi_req_done(struct request *req,
1004                                          blk_status_t status)
1005 {
1006         struct se_cmd *cmd = req->end_io_data;
1007         struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
1008         enum sam_status scsi_status = scmd->result & 0xff;
1009         int valid_data = cmd->data_length - scmd->resid_len;
1010         u8 *cdb = cmd->priv;
1011
1012         if (scsi_status != SAM_STAT_GOOD) {
1013                 pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1014                         " 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
1015         }
1016
1017         pscsi_complete_cmd(cmd, scsi_status, scmd->sense_buffer, valid_data);
1018
1019         switch (host_byte(scmd->result)) {
1020         case DID_OK:
1021                 target_complete_cmd_with_length(cmd, scsi_status, valid_data);
1022                 break;
1023         default:
1024                 pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1025                         " 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
1026                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1027                 break;
1028         }
1029
1030         blk_mq_free_request(req);
1031         return RQ_END_IO_NONE;
1032 }
1033
1034 static const struct target_backend_ops pscsi_ops = {
1035         .name                   = "pscsi",
1036         .owner                  = THIS_MODULE,
1037         .transport_flags_default = TRANSPORT_FLAG_PASSTHROUGH |
1038                                    TRANSPORT_FLAG_PASSTHROUGH_ALUA |
1039                                    TRANSPORT_FLAG_PASSTHROUGH_PGR,
1040         .attach_hba             = pscsi_attach_hba,
1041         .detach_hba             = pscsi_detach_hba,
1042         .pmode_enable_hba       = pscsi_pmode_enable_hba,
1043         .alloc_device           = pscsi_alloc_device,
1044         .configure_device       = pscsi_configure_device,
1045         .destroy_device         = pscsi_destroy_device,
1046         .free_device            = pscsi_free_device,
1047         .parse_cdb              = pscsi_parse_cdb,
1048         .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1049         .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1050         .get_device_type        = pscsi_get_device_type,
1051         .get_blocks             = pscsi_get_blocks,
1052         .tb_dev_attrib_attrs    = passthrough_attrib_attrs,
1053 };
1054
1055 static int __init pscsi_module_init(void)
1056 {
1057         return transport_backend_register(&pscsi_ops);
1058 }
1059
1060 static void __exit pscsi_module_exit(void)
1061 {
1062         target_backend_unregister(&pscsi_ops);
1063 }
1064
1065 MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1066 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1067 MODULE_LICENSE("GPL");
1068
1069 module_init(pscsi_module_init);
1070 module_exit(pscsi_module_exit);