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 void 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_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
 148                         HZ, 1, NULL);
 149         if (ret)
 150                 goto out_free;
 151
 152         /*
 153          * If MODE_SENSE still returns zero, set the default value to 1024.
 154          */
 155         sdev->sector_size = get_unaligned_be24(&buf[9]);
 156 out_free:
 157         if (!sdev->sector_size)
 158                 sdev->sector_size = 1024;
 159
 160         kfree(buf);
 161 }
 162
 163 static void
 164 pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
 165 {
 166         if (sdev->inquiry_len < INQUIRY_LEN)
 167                 return;
 168         /*
 169          * Use sdev->inquiry data from drivers/scsi/scsi_scan.c:scsi_add_lun()
 170          */
 171         BUILD_BUG_ON(sizeof(wwn->vendor) != INQUIRY_VENDOR_LEN + 1);
 172         snprintf(wwn->vendor, sizeof(wwn->vendor),
 173                  "%." __stringify(INQUIRY_VENDOR_LEN) "s", sdev->vendor);
 174         BUILD_BUG_ON(sizeof(wwn->model) != INQUIRY_MODEL_LEN + 1);
 175         snprintf(wwn->model, sizeof(wwn->model),
 176                  "%." __stringify(INQUIRY_MODEL_LEN) "s", sdev->model);
 177         BUILD_BUG_ON(sizeof(wwn->revision) != INQUIRY_REVISION_LEN + 1);
 178         snprintf(wwn->revision, sizeof(wwn->revision),
 179                  "%." __stringify(INQUIRY_REVISION_LEN) "s", sdev->rev);
 180 }
 181
 182 static int
 183 pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
 184 {
 185         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 186         int ret;
 187
 188         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 189         if (!buf)
 190                 return -ENOMEM;
 191
 192         memset(cdb, 0, MAX_COMMAND_SIZE);
 193         cdb[0] = INQUIRY;
 194         cdb[1] = 0x01; /* Query VPD */
 195         cdb[2] = 0x80; /* Unit Serial Number */
 196         put_unaligned_be16(INQUIRY_VPD_SERIAL_LEN, &cdb[3]);
 197
 198         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 199                               INQUIRY_VPD_SERIAL_LEN, NULL, HZ, 1, NULL);
 200         if (ret)
 201                 goto out_free;
 202
 203         snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
 204
 205         wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
 206
 207         kfree(buf);
 208         return 0;
 209
 210 out_free:
 211         kfree(buf);
 212         return -EPERM;
 213 }
 214
 215 static void
 216 pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
 217                 struct t10_wwn *wwn)
 218 {
 219         unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
 220         int ident_len, page_len, off = 4, ret;
 221         struct t10_vpd *vpd;
 222
 223         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 224         if (!buf)
 225                 return;
 226
 227         memset(cdb, 0, MAX_COMMAND_SIZE);
 228         cdb[0] = INQUIRY;
 229         cdb[1] = 0x01; /* Query VPD */
 230         cdb[2] = 0x83; /* Device Identifier */
 231         put_unaligned_be16(INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, &cdb[3]);
 232
 233         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 234                               INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
 235                               NULL, HZ, 1, NULL);
 236         if (ret)
 237                 goto out;
 238
 239         page_len = get_unaligned_be16(&buf[2]);
 240         while (page_len > 0) {
 241                 /* Grab a pointer to the Identification descriptor */
 242                 page_83 = &buf[off];
 243                 ident_len = page_83[3];
 244                 if (!ident_len) {
 245                         pr_err("page_83[3]: identifier"
 246                                         " length zero!\n");
 247                         break;
 248                 }
 249                 pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
 250
 251                 vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
 252                 if (!vpd) {
 253                         pr_err("Unable to allocate memory for"
 254                                         " struct t10_vpd\n");
 255                         goto out;
 256                 }
 257                 INIT_LIST_HEAD(&vpd->vpd_list);
 258
 259                 transport_set_vpd_proto_id(vpd, page_83);
 260                 transport_set_vpd_assoc(vpd, page_83);
 261
 262                 if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
 263                         off += (ident_len + 4);
 264                         page_len -= (ident_len + 4);
 265                         kfree(vpd);
 266                         continue;
 267                 }
 268                 if (transport_set_vpd_ident(vpd, page_83) < 0) {
 269                         off += (ident_len + 4);
 270                         page_len -= (ident_len + 4);
 271                         kfree(vpd);
 272                         continue;
 273                 }
 274
 275                 list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
 276                 off += (ident_len + 4);
 277                 page_len -= (ident_len + 4);
 278         }
 279
 280 out:
 281         kfree(buf);
 282 }
 283
 284 static int pscsi_add_device_to_list(struct se_device *dev,
 285                 struct scsi_device *sd)
 286 {
 287         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 288         struct request_queue *q = sd->request_queue;
 289
 290         pdv->pdv_sd = sd;
 291
 292         if (!sd->queue_depth) {
 293                 sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
 294
 295                 pr_err("Set broken SCSI Device %d:%d:%llu"
 296                         " queue_depth to %d\n", sd->channel, sd->id,
 297                                 sd->lun, sd->queue_depth);
 298         }
 299
 300         dev->dev_attrib.hw_block_size =
 301                 min_not_zero((int)sd->sector_size, 512);
 302         dev->dev_attrib.hw_max_sectors =
 303                 min_not_zero(sd->host->max_sectors, queue_max_hw_sectors(q));
 304         dev->dev_attrib.hw_queue_depth = sd->queue_depth;
 305
 306         /*
 307          * Setup our standard INQUIRY info into se_dev->t10_wwn
 308          */
 309         pscsi_set_inquiry_info(sd, &dev->t10_wwn);
 310
 311         /*
 312          * Locate VPD WWN Information used for various purposes within
 313          * the Storage Engine.
 314          */
 315         if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
 316                 /*
 317                  * If VPD Unit Serial returned GOOD status, try
 318                  * VPD Device Identification page (0x83).
 319                  */
 320                 pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
 321         }
 322
 323         /*
 324          * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
 325          */
 326         if (sd->type == TYPE_TAPE) {
 327                 pscsi_tape_read_blocksize(dev, sd);
 328                 dev->dev_attrib.hw_block_size = sd->sector_size;
 329         }
 330         return 0;
 331 }
 332
 333 static struct se_device *pscsi_alloc_device(struct se_hba *hba,
 334                 const char *name)
 335 {
 336         struct pscsi_dev_virt *pdv;
 337
 338         pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
 339         if (!pdv) {
 340                 pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
 341                 return NULL;
 342         }
 343
 344         pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
 345         return &pdv->dev;
 346 }
 347
 348 /*
 349  * Called with struct Scsi_Host->host_lock called.
 350  */
 351 static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
 352         __releases(sh->host_lock)
 353 {
 354         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 355         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 356         struct Scsi_Host *sh = sd->host;
 357         struct block_device *bd;
 358         int ret;
 359
 360         if (scsi_device_get(sd)) {
 361                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 362                         sh->host_no, sd->channel, sd->id, sd->lun);
 363                 spin_unlock_irq(sh->host_lock);
 364                 return -EIO;
 365         }
 366         spin_unlock_irq(sh->host_lock);
 367         /*
 368          * Claim exclusive struct block_device access to struct scsi_device
 369          * for TYPE_DISK and TYPE_ZBC using supplied udev_path
 370          */
 371         bd = blkdev_get_by_path(dev->udev_path,
 372                                 FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
 373         if (IS_ERR(bd)) {
 374                 pr_err("pSCSI: blkdev_get_by_path() failed\n");
 375                 scsi_device_put(sd);
 376                 return PTR_ERR(bd);
 377         }
 378         pdv->pdv_bd = bd;
 379
 380         ret = pscsi_add_device_to_list(dev, sd);
 381         if (ret) {
 382                 blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 383                 scsi_device_put(sd);
 384                 return ret;
 385         }
 386
 387         pr_debug("CORE_PSCSI[%d] - Added TYPE_%s for %d:%d:%d:%llu\n",
 388                 phv->phv_host_id, sd->type == TYPE_DISK ? "DISK" : "ZBC",
 389                 sh->host_no, sd->channel, sd->id, sd->lun);
 390         return 0;
 391 }
 392
 393 /*
 394  * Called with struct Scsi_Host->host_lock called.
 395  */
 396 static int pscsi_create_type_nondisk(struct se_device *dev, struct scsi_device *sd)
 397         __releases(sh->host_lock)
 398 {
 399         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 400         struct Scsi_Host *sh = sd->host;
 401         int ret;
 402
 403         if (scsi_device_get(sd)) {
 404                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 405                         sh->host_no, sd->channel, sd->id, sd->lun);
 406                 spin_unlock_irq(sh->host_lock);
 407                 return -EIO;
 408         }
 409         spin_unlock_irq(sh->host_lock);
 410
 411         ret = pscsi_add_device_to_list(dev, sd);
 412         if (ret) {
 413                 scsi_device_put(sd);
 414                 return ret;
 415         }
 416         pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
 417                 phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
 418                 sd->channel, sd->id, sd->lun);
 419
 420         return 0;
 421 }
 422
 423 static int pscsi_configure_device(struct se_device *dev)
 424 {
 425         struct se_hba *hba = dev->se_hba;
 426         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 427         struct scsi_device *sd;
 428         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 429         struct Scsi_Host *sh = phv->phv_lld_host;
 430         int legacy_mode_enable = 0;
 431         int ret;
 432
 433         if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
 434             !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
 435             !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
 436                 pr_err("Missing scsi_channel_id=, scsi_target_id= and"
 437                         " scsi_lun_id= parameters\n");
 438                 return -EINVAL;
 439         }
 440
 441         /*
 442          * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
 443          * struct Scsi_Host we will need to bring the TCM/pSCSI object online
 444          */
 445         if (!sh) {
 446                 if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 447                         pr_err("pSCSI: Unable to locate struct"
 448                                 " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
 449                         return -ENODEV;
 450                 }
 451                 /*
 452                  * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
 453                  * reference, we enforce that udev_path has been set
 454                  */
 455                 if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
 456                         pr_err("pSCSI: udev_path attribute has not"
 457                                 " been set before ENABLE=1\n");
 458                         return -EINVAL;
 459                 }
 460                 /*
 461                  * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
 462                  * use the original TCM hba ID to reference Linux/SCSI Host No
 463                  * and enable for PHV_LLD_SCSI_HOST_NO mode.
 464                  */
 465                 if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
 466                         if (hba->dev_count) {
 467                                 pr_err("pSCSI: Unable to set hba_mode"
 468                                         " with active devices\n");
 469                                 return -EEXIST;
 470                         }
 471
 472                         if (pscsi_pmode_enable_hba(hba, 1) != 1)
 473                                 return -ENODEV;
 474
 475                         legacy_mode_enable = 1;
 476                         hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
 477                         sh = phv->phv_lld_host;
 478                 } else {
 479                         sh = scsi_host_lookup(pdv->pdv_host_id);
 480                         if (!sh) {
 481                                 pr_err("pSCSI: Unable to locate"
 482                                         " pdv_host_id: %d\n", pdv->pdv_host_id);
 483                                 return -EINVAL;
 484                         }
 485                         pdv->pdv_lld_host = sh;
 486                 }
 487         } else {
 488                 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
 489                         pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
 490                                 " struct Scsi_Host exists\n");
 491                         return -EEXIST;
 492                 }
 493         }
 494
 495         spin_lock_irq(sh->host_lock);
 496         list_for_each_entry(sd, &sh->__devices, siblings) {
 497                 if ((pdv->pdv_channel_id != sd->channel) ||
 498                     (pdv->pdv_target_id != sd->id) ||
 499                     (pdv->pdv_lun_id != sd->lun))
 500                         continue;
 501                 /*
 502                  * Functions will release the held struct scsi_host->host_lock
 503                  * before calling calling pscsi_add_device_to_list() to register
 504                  * struct scsi_device with target_core_mod.
 505                  */
 506                 switch (sd->type) {
 507                 case TYPE_DISK:
 508                 case TYPE_ZBC:
 509                         ret = pscsi_create_type_disk(dev, sd);
 510                         break;
 511                 default:
 512                         ret = pscsi_create_type_nondisk(dev, sd);
 513                         break;
 514                 }
 515
 516                 if (ret) {
 517                         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 518                                 scsi_host_put(sh);
 519                         else if (legacy_mode_enable) {
 520                                 pscsi_pmode_enable_hba(hba, 0);
 521                                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 522                         }
 523                         pdv->pdv_sd = NULL;
 524                         return ret;
 525                 }
 526                 return 0;
 527         }
 528         spin_unlock_irq(sh->host_lock);
 529
 530         pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
 531                 pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
 532
 533         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 534                 scsi_host_put(sh);
 535         else if (legacy_mode_enable) {
 536                 pscsi_pmode_enable_hba(hba, 0);
 537                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 538         }
 539
 540         return -ENODEV;
 541 }
 542
 543 static void pscsi_dev_call_rcu(struct rcu_head *p)
 544 {
 545         struct se_device *dev = container_of(p, struct se_device, rcu_head);
 546         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 547
 548         kfree(pdv);
 549 }
 550
 551 static void pscsi_free_device(struct se_device *dev)
 552 {
 553         call_rcu(&dev->rcu_head, pscsi_dev_call_rcu);
 554 }
 555
 556 static void pscsi_destroy_device(struct se_device *dev)
 557 {
 558         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 559         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 560         struct scsi_device *sd = pdv->pdv_sd;
 561
 562         if (sd) {
 563                 /*
 564                  * Release exclusive pSCSI internal struct block_device claim for
 565                  * struct scsi_device with TYPE_DISK or TYPE_ZBC
 566                  * from pscsi_create_type_disk()
 567                  */
 568                 if ((sd->type == TYPE_DISK || sd->type == TYPE_ZBC) &&
 569                     pdv->pdv_bd) {
 570                         blkdev_put(pdv->pdv_bd,
 571                                    FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 572                         pdv->pdv_bd = NULL;
 573                 }
 574                 /*
 575                  * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
 576                  * to struct Scsi_Host now.
 577                  */
 578                 if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
 579                     (phv->phv_lld_host != NULL))
 580                         scsi_host_put(phv->phv_lld_host);
 581                 else if (pdv->pdv_lld_host)
 582                         scsi_host_put(pdv->pdv_lld_host);
 583
 584                 scsi_device_put(sd);
 585
 586                 pdv->pdv_sd = NULL;
 587         }
 588 }
 589
 590 static void pscsi_complete_cmd(struct se_cmd *cmd, u8 scsi_status,
 591                                unsigned char *req_sense)
 592 {
 593         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 594         struct scsi_device *sd = pdv->pdv_sd;
 595         unsigned char *cdb = cmd->priv;
 596
 597         /*
 598          * Special case for REPORT_LUNs which is emulated and not passed on.
 599          */
 600         if (!cdb)
 601                 return;
 602
 603         /*
 604          * Hack to make sure that Write-Protect modepage is set if R/O mode is
 605          * forced.
 606          */
 607         if (!cmd->data_length)
 608                 goto after_mode_sense;
 609
 610         if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
 611             scsi_status == SAM_STAT_GOOD) {
 612                 bool read_only = target_lun_is_rdonly(cmd);
 613
 614                 if (read_only) {
 615                         unsigned char *buf;
 616
 617                         buf = transport_kmap_data_sg(cmd);
 618                         if (!buf) {
 619                                 ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
 620                         } else {
 621                                 if (cdb[0] == MODE_SENSE_10) {
 622                                         if (!(buf[3] & 0x80))
 623                                                 buf[3] |= 0x80;
 624                                 } else {
 625                                         if (!(buf[2] & 0x80))
 626                                                 buf[2] |= 0x80;
 627                                 }
 628
 629                                 transport_kunmap_data_sg(cmd);
 630                         }
 631                 }
 632         }
 633 after_mode_sense:
 634
 635         if (sd->type != TYPE_TAPE || !cmd->data_length)
 636                 goto after_mode_select;
 637
 638         /*
 639          * Hack to correctly obtain the initiator requested blocksize for
 640          * TYPE_TAPE.  Since this value is dependent upon each tape media,
 641          * struct scsi_device->sector_size will not contain the correct value
 642          * by default, so we go ahead and set it so
 643          * TRANSPORT(dev)->get_blockdev() returns the correct value to the
 644          * storage engine.
 645          */
 646         if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
 647              scsi_status == SAM_STAT_GOOD) {
 648                 unsigned char *buf;
 649                 u16 bdl;
 650                 u32 blocksize;
 651
 652                 buf = sg_virt(&cmd->t_data_sg[0]);
 653                 if (!buf) {
 654                         pr_err("Unable to get buf for scatterlist\n");
 655                         goto after_mode_select;
 656                 }
 657
 658                 if (cdb[0] == MODE_SELECT)
 659                         bdl = buf[3];
 660                 else
 661                         bdl = get_unaligned_be16(&buf[6]);
 662
 663                 if (!bdl)
 664                         goto after_mode_select;
 665
 666                 if (cdb[0] == MODE_SELECT)
 667                         blocksize = get_unaligned_be24(&buf[9]);
 668                 else
 669                         blocksize = get_unaligned_be24(&buf[13]);
 670
 671                 sd->sector_size = blocksize;
 672         }
 673 after_mode_select:
 674
 675         if (scsi_status == SAM_STAT_CHECK_CONDITION) {
 676                 transport_copy_sense_to_cmd(cmd, req_sense);
 677
 678                 /*
 679                  * check for TAPE device reads with
 680                  * FM/EOM/ILI set, so that we can get data
 681                  * back despite framework assumption that a
 682                  * check condition means there is no data
 683                  */
 684                 if (sd->type == TYPE_TAPE &&
 685                     cmd->data_direction == DMA_FROM_DEVICE) {
 686                         /*
 687                          * is sense data valid, fixed format,
 688                          * and have FM, EOM, or ILI set?
 689                          */
 690                         if (req_sense[0] == 0xf0 &&     /* valid, fixed format */
 691                             req_sense[2] & 0xe0 &&      /* FM, EOM, or ILI */
 692                             (req_sense[2] & 0xf) == 0) { /* key==NO_SENSE */
 693                                 pr_debug("Tape FM/EOM/ILI status detected. Treat as normal read.\n");
 694                                 cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL;
 695                         }
 696                 }
 697         }
 698 }
 699
 700 enum {
 701         Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
 702         Opt_scsi_lun_id, Opt_err
 703 };
 704
 705 static match_table_t tokens = {
 706         {Opt_scsi_host_id, "scsi_host_id=%d"},
 707         {Opt_scsi_channel_id, "scsi_channel_id=%d"},
 708         {Opt_scsi_target_id, "scsi_target_id=%d"},
 709         {Opt_scsi_lun_id, "scsi_lun_id=%d"},
 710         {Opt_err, NULL}
 711 };
 712
 713 static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
 714                 const char *page, ssize_t count)
 715 {
 716         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 717         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 718         char *orig, *ptr, *opts;
 719         substring_t args[MAX_OPT_ARGS];
 720         int ret = 0, arg, token;
 721
 722         opts = kstrdup(page, GFP_KERNEL);
 723         if (!opts)
 724                 return -ENOMEM;
 725
 726         orig = opts;
 727
 728         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 729                 if (!*ptr)
 730                         continue;
 731
 732                 token = match_token(ptr, tokens, args);
 733                 switch (token) {
 734                 case Opt_scsi_host_id:
 735                         if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 736                                 pr_err("PSCSI[%d]: Unable to accept"
 737                                         " scsi_host_id while phv_mode =="
 738                                         " PHV_LLD_SCSI_HOST_NO\n",
 739                                         phv->phv_host_id);
 740                                 ret = -EINVAL;
 741                                 goto out;
 742                         }
 743                         ret = match_int(args, &arg);
 744                         if (ret)
 745                                 goto out;
 746                         pdv->pdv_host_id = arg;
 747                         pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
 748                                 " %d\n", phv->phv_host_id, pdv->pdv_host_id);
 749                         pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
 750                         break;
 751                 case Opt_scsi_channel_id:
 752                         ret = match_int(args, &arg);
 753                         if (ret)
 754                                 goto out;
 755                         pdv->pdv_channel_id = arg;
 756                         pr_debug("PSCSI[%d]: Referencing SCSI Channel"
 757                                 " ID: %d\n",  phv->phv_host_id,
 758                                 pdv->pdv_channel_id);
 759                         pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
 760                         break;
 761                 case Opt_scsi_target_id:
 762                         ret = match_int(args, &arg);
 763                         if (ret)
 764                                 goto out;
 765                         pdv->pdv_target_id = arg;
 766                         pr_debug("PSCSI[%d]: Referencing SCSI Target"
 767                                 " ID: %d\n", phv->phv_host_id,
 768                                 pdv->pdv_target_id);
 769                         pdv->pdv_flags |= PDF_HAS_TARGET_ID;
 770                         break;
 771                 case Opt_scsi_lun_id:
 772                         ret = match_int(args, &arg);
 773                         if (ret)
 774                                 goto out;
 775                         pdv->pdv_lun_id = arg;
 776                         pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
 777                                 " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
 778                         pdv->pdv_flags |= PDF_HAS_LUN_ID;
 779                         break;
 780                 default:
 781                         break;
 782                 }
 783         }
 784
 785 out:
 786         kfree(orig);
 787         return (!ret) ? count : ret;
 788 }
 789
 790 static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
 791 {
 792         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 793         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 794         struct scsi_device *sd = pdv->pdv_sd;
 795         unsigned char host_id[16];
 796         ssize_t bl;
 797
 798         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 799                 snprintf(host_id, 16, "%d", pdv->pdv_host_id);
 800         else
 801                 snprintf(host_id, 16, "PHBA Mode");
 802
 803         bl = sprintf(b, "SCSI Device Bus Location:"
 804                 " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
 805                 pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
 806                 host_id);
 807
 808         if (sd) {
 809                 bl += sprintf(b + bl, "        Vendor: %."
 810                         __stringify(INQUIRY_VENDOR_LEN) "s", sd->vendor);
 811                 bl += sprintf(b + bl, " Model: %."
 812                         __stringify(INQUIRY_MODEL_LEN) "s", sd->model);
 813                 bl += sprintf(b + bl, " Rev: %."
 814                         __stringify(INQUIRY_REVISION_LEN) "s\n", sd->rev);
 815         }
 816         return bl;
 817 }
 818
 819 static void pscsi_bi_endio(struct bio *bio)
 820 {
 821         bio_put(bio);
 822 }
 823
 824 static inline struct bio *pscsi_get_bio(int nr_vecs)
 825 {
 826         struct bio *bio;
 827         /*
 828          * Use bio_malloc() following the comment in for bio -> struct request
 829          * in block/blk-core.c:blk_make_request()
 830          */
 831         bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
 832         if (!bio) {
 833                 pr_err("PSCSI: bio_kmalloc() failed\n");
 834                 return NULL;
 835         }
 836         bio->bi_end_io = pscsi_bi_endio;
 837
 838         return bio;
 839 }
 840
 841 static sense_reason_t
 842 pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 843                 struct request *req)
 844 {
 845         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 846         struct bio *bio = NULL;
 847         struct page *page;
 848         struct scatterlist *sg;
 849         u32 data_len = cmd->data_length, i, len, bytes, off;
 850         int nr_pages = (cmd->data_length + sgl[0].offset +
 851                         PAGE_SIZE - 1) >> PAGE_SHIFT;
 852         int nr_vecs = 0, rc;
 853         int rw = (cmd->data_direction == DMA_TO_DEVICE);
 854
 855         BUG_ON(!cmd->data_length);
 856
 857         pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
 858
 859         for_each_sg(sgl, sg, sgl_nents, i) {
 860                 page = sg_page(sg);
 861                 off = sg->offset;
 862                 len = sg->length;
 863
 864                 pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
 865                         page, len, off);
 866
 867                 /*
 868                  * We only have one page of data in each sg element,
 869                  * we can not cross a page boundary.
 870                  */
 871                 if (off + len > PAGE_SIZE)
 872                         goto fail;
 873
 874                 if (len > 0 && data_len > 0) {
 875                         bytes = min_t(unsigned int, len, PAGE_SIZE - off);
 876                         bytes = min(bytes, data_len);
 877
 878                         if (!bio) {
 879 new_bio:
 880                                 nr_vecs = bio_max_segs(nr_pages);
 881                                 /*
 882                                  * Calls bio_kmalloc() and sets bio->bi_end_io()
 883                                  */
 884                                 bio = pscsi_get_bio(nr_vecs);
 885                                 if (!bio)
 886                                         goto fail;
 887
 888                                 if (rw)
 889                                         bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
 890
 891                                 pr_debug("PSCSI: Allocated bio: %p,"
 892                                         " dir: %s nr_vecs: %d\n", bio,
 893                                         (rw) ? "rw" : "r", nr_vecs);
 894                         }
 895
 896                         pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
 897                                 " bio: %p page: %p len: %d off: %d\n", i, bio,
 898                                 page, len, off);
 899
 900                         rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
 901                                         bio, page, bytes, off);
 902                         pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
 903                                 bio_segments(bio), nr_vecs);
 904                         if (rc != bytes) {
 905                                 pr_debug("PSCSI: Reached bio->bi_vcnt max:"
 906                                         " %d i: %d bio: %p, allocating another"
 907                                         " bio\n", bio->bi_vcnt, i, bio);
 908
 909                                 rc = blk_rq_append_bio(req, bio);
 910                                 if (rc) {
 911                                         pr_err("pSCSI: failed to append bio\n");
 912                                         goto fail;
 913                                 }
 914
 915                                 /*
 916                                  * Clear the pointer so that another bio will
 917                                  * be allocated with pscsi_get_bio() above.
 918                                  */
 919                                 bio = NULL;
 920                                 goto new_bio;
 921                         }
 922
 923                         data_len -= bytes;
 924                 }
 925         }
 926
 927         if (bio) {
 928                 rc = blk_rq_append_bio(req, bio);
 929                 if (rc) {
 930                         pr_err("pSCSI: failed to append bio\n");
 931                         goto fail;
 932                 }
 933         }
 934
 935         return 0;
 936 fail:
 937         if (bio)
 938                 bio_put(bio);
 939         while (req->bio) {
 940                 bio = req->bio;
 941                 req->bio = bio->bi_next;
 942                 bio_put(bio);
 943         }
 944         req->biotail = NULL;
 945         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 946 }
 947
 948 static sense_reason_t
 949 pscsi_parse_cdb(struct se_cmd *cmd)
 950 {
 951         if (cmd->se_cmd_flags & SCF_BIDI)
 952                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 953
 954         return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
 955 }
 956
 957 static sense_reason_t
 958 pscsi_execute_cmd(struct se_cmd *cmd)
 959 {
 960         struct scatterlist *sgl = cmd->t_data_sg;
 961         u32 sgl_nents = cmd->t_data_nents;
 962         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 963         struct scsi_cmnd *scmd;
 964         struct request *req;
 965         sense_reason_t ret;
 966
 967         req = scsi_alloc_request(pdv->pdv_sd->request_queue,
 968                         cmd->data_direction == DMA_TO_DEVICE ?
 969                         REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
 970         if (IS_ERR(req))
 971                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 972
 973         if (sgl) {
 974                 ret = pscsi_map_sg(cmd, sgl, sgl_nents, req);
 975                 if (ret)
 976                         goto fail_put_request;
 977         }
 978
 979         req->end_io = pscsi_req_done;
 980         req->end_io_data = cmd;
 981
 982         scmd = blk_mq_rq_to_pdu(req);
 983         scmd->cmd_len = scsi_command_size(cmd->t_task_cdb);
 984         if (scmd->cmd_len > sizeof(scmd->cmnd)) {
 985                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 986                 goto fail_put_request;
 987         }
 988         memcpy(scmd->cmnd, cmd->t_task_cdb, scmd->cmd_len);
 989
 990         if (pdv->pdv_sd->type == TYPE_DISK ||
 991             pdv->pdv_sd->type == TYPE_ZBC)
 992                 req->timeout = PS_TIMEOUT_DISK;
 993         else
 994                 req->timeout = PS_TIMEOUT_OTHER;
 995         scmd->allowed = PS_RETRY;
 996
 997         cmd->priv = scmd->cmnd;
 998
 999         blk_execute_rq_nowait(req, cmd->sam_task_attr == TCM_HEAD_TAG,
1000                         pscsi_req_done);
1001
1002         return 0;
1003
1004 fail_put_request:
1005         blk_mq_free_request(req);
1006         return ret;
1007 }
1008
1009 /*      pscsi_get_device_type():
1010  *
1011  *
1012  */
1013 static u32 pscsi_get_device_type(struct se_device *dev)
1014 {
1015         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1016         struct scsi_device *sd = pdv->pdv_sd;
1017
1018         return (sd) ? sd->type : TYPE_NO_LUN;
1019 }
1020
1021 static sector_t pscsi_get_blocks(struct se_device *dev)
1022 {
1023         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1024
1025         if (pdv->pdv_bd)
1026                 return bdev_nr_sectors(pdv->pdv_bd);
1027         return 0;
1028 }
1029
1030 static void pscsi_req_done(struct request *req, blk_status_t status)
1031 {
1032         struct se_cmd *cmd = req->end_io_data;
1033         struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
1034         enum sam_status scsi_status = scmd->result & 0xff;
1035         u8 *cdb = cmd->priv;
1036
1037         if (scsi_status != SAM_STAT_GOOD) {
1038                 pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1039                         " 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
1040         }
1041
1042         pscsi_complete_cmd(cmd, scsi_status, scmd->sense_buffer);
1043
1044         switch (host_byte(scmd->result)) {
1045         case DID_OK:
1046                 target_complete_cmd_with_length(cmd, scsi_status,
1047                         cmd->data_length - scmd->resid_len);
1048                 break;
1049         default:
1050                 pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1051                         " 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
1052                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1053                 break;
1054         }
1055
1056         blk_mq_free_request(req);
1057 }
1058
1059 static const struct target_backend_ops pscsi_ops = {
1060         .name                   = "pscsi",
1061         .owner                  = THIS_MODULE,
1062         .transport_flags_default = TRANSPORT_FLAG_PASSTHROUGH |
1063                                    TRANSPORT_FLAG_PASSTHROUGH_ALUA |
1064                                    TRANSPORT_FLAG_PASSTHROUGH_PGR,
1065         .attach_hba             = pscsi_attach_hba,
1066         .detach_hba             = pscsi_detach_hba,
1067         .pmode_enable_hba       = pscsi_pmode_enable_hba,
1068         .alloc_device           = pscsi_alloc_device,
1069         .configure_device       = pscsi_configure_device,
1070         .destroy_device         = pscsi_destroy_device,
1071         .free_device            = pscsi_free_device,
1072         .parse_cdb              = pscsi_parse_cdb,
1073         .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1074         .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1075         .get_device_type        = pscsi_get_device_type,
1076         .get_blocks             = pscsi_get_blocks,
1077         .tb_dev_attrib_attrs    = passthrough_attrib_attrs,
1078 };
1079
1080 static int __init pscsi_module_init(void)
1081 {
1082         return transport_backend_register(&pscsi_ops);
1083 }
1084
1085 static void __exit pscsi_module_exit(void)
1086 {
1087         target_backend_unregister(&pscsi_ops);
1088 }
1089
1090 MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1091 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1092 MODULE_LICENSE("GPL");
1093
1094 module_init(pscsi_module_init);
1095 module_exit(pscsi_module_exit);