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/genhd.h>
  21 #include <linux/cdrom.h>
  22 #include <linux/ratelimit.h>
  23 #include <linux/module.h>
  24 #include <asm/unaligned.h>
  25
  26 #include <scsi/scsi_device.h>
  27 #include <scsi/scsi_host.h>
  28 #include <scsi/scsi_tcq.h>
  29
  30 #include <target/target_core_base.h>
  31 #include <target/target_core_backend.h>
  32
  33 #include "target_core_alua.h"
  34 #include "target_core_internal.h"
  35 #include "target_core_pscsi.h"
  36
  37 #define ISPRINT(a)  ((a >= ' ') && (a <= '~'))
  38
  39 static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
  40 {
  41         return container_of(dev, struct pscsi_dev_virt, dev);
  42 }
  43
  44 static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
  45 static void pscsi_req_done(struct request *, blk_status_t);
  46
  47 /*      pscsi_attach_hba():
  48  *
  49  *      pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
  50  *      from the passed SCSI Host ID.
  51  */
  52 static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
  53 {
  54         struct pscsi_hba_virt *phv;
  55
  56         phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
  57         if (!phv) {
  58                 pr_err("Unable to allocate struct pscsi_hba_virt\n");
  59                 return -ENOMEM;
  60         }
  61         phv->phv_host_id = host_id;
  62         phv->phv_mode = PHV_VIRTUAL_HOST_ID;
  63
  64         hba->hba_ptr = phv;
  65
  66         pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
  67                 " Generic Target Core Stack %s\n", hba->hba_id,
  68                 PSCSI_VERSION, TARGET_CORE_VERSION);
  69         pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
  70                hba->hba_id);
  71
  72         return 0;
  73 }
  74
  75 static void pscsi_detach_hba(struct se_hba *hba)
  76 {
  77         struct pscsi_hba_virt *phv = hba->hba_ptr;
  78         struct Scsi_Host *scsi_host = phv->phv_lld_host;
  79
  80         if (scsi_host) {
  81                 scsi_host_put(scsi_host);
  82
  83                 pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
  84                         " Generic Target Core\n", hba->hba_id,
  85                         (scsi_host->hostt->name) ? (scsi_host->hostt->name) :
  86                         "Unknown");
  87         } else
  88                 pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
  89                         " from Generic Target Core\n", hba->hba_id);
  90
  91         kfree(phv);
  92         hba->hba_ptr = NULL;
  93 }
  94
  95 static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
  96 {
  97         struct pscsi_hba_virt *phv = hba->hba_ptr;
  98         struct Scsi_Host *sh = phv->phv_lld_host;
  99         /*
 100          * Release the struct Scsi_Host
 101          */
 102         if (!mode_flag) {
 103                 if (!sh)
 104                         return 0;
 105
 106                 phv->phv_lld_host = NULL;
 107                 phv->phv_mode = PHV_VIRTUAL_HOST_ID;
 108
 109                 pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
 110                         " %s\n", hba->hba_id, (sh->hostt->name) ?
 111                         (sh->hostt->name) : "Unknown");
 112
 113                 scsi_host_put(sh);
 114                 return 0;
 115         }
 116         /*
 117          * Otherwise, locate struct Scsi_Host from the original passed
 118          * pSCSI Host ID and enable for phba mode
 119          */
 120         sh = scsi_host_lookup(phv->phv_host_id);
 121         if (!sh) {
 122                 pr_err("pSCSI: Unable to locate SCSI Host for"
 123                         " phv_host_id: %d\n", phv->phv_host_id);
 124                 return -EINVAL;
 125         }
 126
 127         phv->phv_lld_host = sh;
 128         phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
 129
 130         pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
 131                 hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
 132
 133         return 1;
 134 }
 135
 136 static void pscsi_tape_read_blocksize(struct se_device *dev,
 137                 struct scsi_device *sdev)
 138 {
 139         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 140         int ret;
 141
 142         buf = kzalloc(12, GFP_KERNEL);
 143         if (!buf)
 144                 goto out_free;
 145
 146         memset(cdb, 0, MAX_COMMAND_SIZE);
 147         cdb[0] = MODE_SENSE;
 148         cdb[4] = 0x0c; /* 12 bytes */
 149
 150         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
 151                         HZ, 1, NULL);
 152         if (ret)
 153                 goto out_free;
 154
 155         /*
 156          * If MODE_SENSE still returns zero, set the default value to 1024.
 157          */
 158         sdev->sector_size = get_unaligned_be24(&buf[9]);
 159 out_free:
 160         if (!sdev->sector_size)
 161                 sdev->sector_size = 1024;
 162
 163         kfree(buf);
 164 }
 165
 166 static void
 167 pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
 168 {
 169         if (sdev->inquiry_len < INQUIRY_LEN)
 170                 return;
 171         /*
 172          * Use sdev->inquiry data from drivers/scsi/scsi_scan.c:scsi_add_lun()
 173          */
 174         BUILD_BUG_ON(sizeof(wwn->vendor) != INQUIRY_VENDOR_LEN + 1);
 175         snprintf(wwn->vendor, sizeof(wwn->vendor),
 176                  "%." __stringify(INQUIRY_VENDOR_LEN) "s", sdev->vendor);
 177         BUILD_BUG_ON(sizeof(wwn->model) != INQUIRY_MODEL_LEN + 1);
 178         snprintf(wwn->model, sizeof(wwn->model),
 179                  "%." __stringify(INQUIRY_MODEL_LEN) "s", sdev->model);
 180         BUILD_BUG_ON(sizeof(wwn->revision) != INQUIRY_REVISION_LEN + 1);
 181         snprintf(wwn->revision, sizeof(wwn->revision),
 182                  "%." __stringify(INQUIRY_REVISION_LEN) "s", sdev->rev);
 183 }
 184
 185 static int
 186 pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
 187 {
 188         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 189         int ret;
 190
 191         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 192         if (!buf)
 193                 return -ENOMEM;
 194
 195         memset(cdb, 0, MAX_COMMAND_SIZE);
 196         cdb[0] = INQUIRY;
 197         cdb[1] = 0x01; /* Query VPD */
 198         cdb[2] = 0x80; /* Unit Serial Number */
 199         put_unaligned_be16(INQUIRY_VPD_SERIAL_LEN, &cdb[3]);
 200
 201         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 202                               INQUIRY_VPD_SERIAL_LEN, NULL, HZ, 1, NULL);
 203         if (ret)
 204                 goto out_free;
 205
 206         snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
 207
 208         wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
 209
 210         kfree(buf);
 211         return 0;
 212
 213 out_free:
 214         kfree(buf);
 215         return -EPERM;
 216 }
 217
 218 static void
 219 pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
 220                 struct t10_wwn *wwn)
 221 {
 222         unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
 223         int ident_len, page_len, off = 4, ret;
 224         struct t10_vpd *vpd;
 225
 226         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 227         if (!buf)
 228                 return;
 229
 230         memset(cdb, 0, MAX_COMMAND_SIZE);
 231         cdb[0] = INQUIRY;
 232         cdb[1] = 0x01; /* Query VPD */
 233         cdb[2] = 0x83; /* Device Identifier */
 234         put_unaligned_be16(INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, &cdb[3]);
 235
 236         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 237                               INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
 238                               NULL, HZ, 1, NULL);
 239         if (ret)
 240                 goto out;
 241
 242         page_len = get_unaligned_be16(&buf[2]);
 243         while (page_len > 0) {
 244                 /* Grab a pointer to the Identification descriptor */
 245                 page_83 = &buf[off];
 246                 ident_len = page_83[3];
 247                 if (!ident_len) {
 248                         pr_err("page_83[3]: identifier"
 249                                         " length zero!\n");
 250                         break;
 251                 }
 252                 pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
 253
 254                 vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
 255                 if (!vpd) {
 256                         pr_err("Unable to allocate memory for"
 257                                         " struct t10_vpd\n");
 258                         goto out;
 259                 }
 260                 INIT_LIST_HEAD(&vpd->vpd_list);
 261
 262                 transport_set_vpd_proto_id(vpd, page_83);
 263                 transport_set_vpd_assoc(vpd, page_83);
 264
 265                 if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
 266                         off += (ident_len + 4);
 267                         page_len -= (ident_len + 4);
 268                         kfree(vpd);
 269                         continue;
 270                 }
 271                 if (transport_set_vpd_ident(vpd, page_83) < 0) {
 272                         off += (ident_len + 4);
 273                         page_len -= (ident_len + 4);
 274                         kfree(vpd);
 275                         continue;
 276                 }
 277
 278                 list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
 279                 off += (ident_len + 4);
 280                 page_len -= (ident_len + 4);
 281         }
 282
 283 out:
 284         kfree(buf);
 285 }
 286
 287 static int pscsi_add_device_to_list(struct se_device *dev,
 288                 struct scsi_device *sd)
 289 {
 290         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 291         struct request_queue *q = sd->request_queue;
 292
 293         pdv->pdv_sd = sd;
 294
 295         if (!sd->queue_depth) {
 296                 sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
 297
 298                 pr_err("Set broken SCSI Device %d:%d:%llu"
 299                         " queue_depth to %d\n", sd->channel, sd->id,
 300                                 sd->lun, sd->queue_depth);
 301         }
 302
 303         dev->dev_attrib.hw_block_size =
 304                 min_not_zero((int)sd->sector_size, 512);
 305         dev->dev_attrib.hw_max_sectors =
 306                 min_not_zero(sd->host->max_sectors, queue_max_hw_sectors(q));
 307         dev->dev_attrib.hw_queue_depth = sd->queue_depth;
 308
 309         /*
 310          * Setup our standard INQUIRY info into se_dev->t10_wwn
 311          */
 312         pscsi_set_inquiry_info(sd, &dev->t10_wwn);
 313
 314         /*
 315          * Locate VPD WWN Information used for various purposes within
 316          * the Storage Engine.
 317          */
 318         if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
 319                 /*
 320                  * If VPD Unit Serial returned GOOD status, try
 321                  * VPD Device Identification page (0x83).
 322                  */
 323                 pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
 324         }
 325
 326         /*
 327          * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
 328          */
 329         if (sd->type == TYPE_TAPE) {
 330                 pscsi_tape_read_blocksize(dev, sd);
 331                 dev->dev_attrib.hw_block_size = sd->sector_size;
 332         }
 333         return 0;
 334 }
 335
 336 static struct se_device *pscsi_alloc_device(struct se_hba *hba,
 337                 const char *name)
 338 {
 339         struct pscsi_dev_virt *pdv;
 340
 341         pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
 342         if (!pdv) {
 343                 pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
 344                 return NULL;
 345         }
 346
 347         pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
 348         return &pdv->dev;
 349 }
 350
 351 /*
 352  * Called with struct Scsi_Host->host_lock called.
 353  */
 354 static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
 355         __releases(sh->host_lock)
 356 {
 357         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 358         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 359         struct Scsi_Host *sh = sd->host;
 360         struct block_device *bd;
 361         int ret;
 362
 363         if (scsi_device_get(sd)) {
 364                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 365                         sh->host_no, sd->channel, sd->id, sd->lun);
 366                 spin_unlock_irq(sh->host_lock);
 367                 return -EIO;
 368         }
 369         spin_unlock_irq(sh->host_lock);
 370         /*
 371          * Claim exclusive struct block_device access to struct scsi_device
 372          * for TYPE_DISK and TYPE_ZBC using supplied udev_path
 373          */
 374         bd = blkdev_get_by_path(dev->udev_path,
 375                                 FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
 376         if (IS_ERR(bd)) {
 377                 pr_err("pSCSI: blkdev_get_by_path() failed\n");
 378                 scsi_device_put(sd);
 379                 return PTR_ERR(bd);
 380         }
 381         pdv->pdv_bd = bd;
 382
 383         ret = pscsi_add_device_to_list(dev, sd);
 384         if (ret) {
 385                 blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 386                 scsi_device_put(sd);
 387                 return ret;
 388         }
 389
 390         pr_debug("CORE_PSCSI[%d] - Added TYPE_%s for %d:%d:%d:%llu\n",
 391                 phv->phv_host_id, sd->type == TYPE_DISK ? "DISK" : "ZBC",
 392                 sh->host_no, sd->channel, sd->id, sd->lun);
 393         return 0;
 394 }
 395
 396 /*
 397  * Called with struct Scsi_Host->host_lock called.
 398  */
 399 static int pscsi_create_type_nondisk(struct se_device *dev, struct scsi_device *sd)
 400         __releases(sh->host_lock)
 401 {
 402         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 403         struct Scsi_Host *sh = sd->host;
 404         int ret;
 405
 406         if (scsi_device_get(sd)) {
 407                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 408                         sh->host_no, sd->channel, sd->id, sd->lun);
 409                 spin_unlock_irq(sh->host_lock);
 410                 return -EIO;
 411         }
 412         spin_unlock_irq(sh->host_lock);
 413
 414         ret = pscsi_add_device_to_list(dev, sd);
 415         if (ret) {
 416                 scsi_device_put(sd);
 417                 return ret;
 418         }
 419         pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
 420                 phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
 421                 sd->channel, sd->id, sd->lun);
 422
 423         return 0;
 424 }
 425
 426 static int pscsi_configure_device(struct se_device *dev)
 427 {
 428         struct se_hba *hba = dev->se_hba;
 429         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 430         struct scsi_device *sd;
 431         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 432         struct Scsi_Host *sh = phv->phv_lld_host;
 433         int legacy_mode_enable = 0;
 434         int ret;
 435
 436         if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
 437             !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
 438             !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
 439                 pr_err("Missing scsi_channel_id=, scsi_target_id= and"
 440                         " scsi_lun_id= parameters\n");
 441                 return -EINVAL;
 442         }
 443
 444         /*
 445          * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
 446          * struct Scsi_Host we will need to bring the TCM/pSCSI object online
 447          */
 448         if (!sh) {
 449                 if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 450                         pr_err("pSCSI: Unable to locate struct"
 451                                 " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
 452                         return -ENODEV;
 453                 }
 454                 /*
 455                  * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
 456                  * reference, we enforce that udev_path has been set
 457                  */
 458                 if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
 459                         pr_err("pSCSI: udev_path attribute has not"
 460                                 " been set before ENABLE=1\n");
 461                         return -EINVAL;
 462                 }
 463                 /*
 464                  * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
 465                  * use the original TCM hba ID to reference Linux/SCSI Host No
 466                  * and enable for PHV_LLD_SCSI_HOST_NO mode.
 467                  */
 468                 if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
 469                         if (hba->dev_count) {
 470                                 pr_err("pSCSI: Unable to set hba_mode"
 471                                         " with active devices\n");
 472                                 return -EEXIST;
 473                         }
 474
 475                         if (pscsi_pmode_enable_hba(hba, 1) != 1)
 476                                 return -ENODEV;
 477
 478                         legacy_mode_enable = 1;
 479                         hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
 480                         sh = phv->phv_lld_host;
 481                 } else {
 482                         sh = scsi_host_lookup(pdv->pdv_host_id);
 483                         if (!sh) {
 484                                 pr_err("pSCSI: Unable to locate"
 485                                         " pdv_host_id: %d\n", pdv->pdv_host_id);
 486                                 return -EINVAL;
 487                         }
 488                         pdv->pdv_lld_host = sh;
 489                 }
 490         } else {
 491                 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
 492                         pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
 493                                 " struct Scsi_Host exists\n");
 494                         return -EEXIST;
 495                 }
 496         }
 497
 498         spin_lock_irq(sh->host_lock);
 499         list_for_each_entry(sd, &sh->__devices, siblings) {
 500                 if ((pdv->pdv_channel_id != sd->channel) ||
 501                     (pdv->pdv_target_id != sd->id) ||
 502                     (pdv->pdv_lun_id != sd->lun))
 503                         continue;
 504                 /*
 505                  * Functions will release the held struct scsi_host->host_lock
 506                  * before calling calling pscsi_add_device_to_list() to register
 507                  * struct scsi_device with target_core_mod.
 508                  */
 509                 switch (sd->type) {
 510                 case TYPE_DISK:
 511                 case TYPE_ZBC:
 512                         ret = pscsi_create_type_disk(dev, sd);
 513                         break;
 514                 default:
 515                         ret = pscsi_create_type_nondisk(dev, sd);
 516                         break;
 517                 }
 518
 519                 if (ret) {
 520                         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 521                                 scsi_host_put(sh);
 522                         else if (legacy_mode_enable) {
 523                                 pscsi_pmode_enable_hba(hba, 0);
 524                                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 525                         }
 526                         pdv->pdv_sd = NULL;
 527                         return ret;
 528                 }
 529                 return 0;
 530         }
 531         spin_unlock_irq(sh->host_lock);
 532
 533         pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
 534                 pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
 535
 536         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 537                 scsi_host_put(sh);
 538         else if (legacy_mode_enable) {
 539                 pscsi_pmode_enable_hba(hba, 0);
 540                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 541         }
 542
 543         return -ENODEV;
 544 }
 545
 546 static void pscsi_dev_call_rcu(struct rcu_head *p)
 547 {
 548         struct se_device *dev = container_of(p, struct se_device, rcu_head);
 549         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 550
 551         kfree(pdv);
 552 }
 553
 554 static void pscsi_free_device(struct se_device *dev)
 555 {
 556         call_rcu(&dev->rcu_head, pscsi_dev_call_rcu);
 557 }
 558
 559 static void pscsi_destroy_device(struct se_device *dev)
 560 {
 561         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 562         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 563         struct scsi_device *sd = pdv->pdv_sd;
 564
 565         if (sd) {
 566                 /*
 567                  * Release exclusive pSCSI internal struct block_device claim for
 568                  * struct scsi_device with TYPE_DISK or TYPE_ZBC
 569                  * from pscsi_create_type_disk()
 570                  */
 571                 if ((sd->type == TYPE_DISK || sd->type == TYPE_ZBC) &&
 572                     pdv->pdv_bd) {
 573                         blkdev_put(pdv->pdv_bd,
 574                                    FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 575                         pdv->pdv_bd = NULL;
 576                 }
 577                 /*
 578                  * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
 579                  * to struct Scsi_Host now.
 580                  */
 581                 if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
 582                     (phv->phv_lld_host != NULL))
 583                         scsi_host_put(phv->phv_lld_host);
 584                 else if (pdv->pdv_lld_host)
 585                         scsi_host_put(pdv->pdv_lld_host);
 586
 587                 scsi_device_put(sd);
 588
 589                 pdv->pdv_sd = NULL;
 590         }
 591 }
 592
 593 static void pscsi_complete_cmd(struct se_cmd *cmd, u8 scsi_status,
 594                                unsigned char *req_sense)
 595 {
 596         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 597         struct scsi_device *sd = pdv->pdv_sd;
 598         struct pscsi_plugin_task *pt = cmd->priv;
 599         unsigned char *cdb;
 600         /*
 601          * Special case for REPORT_LUNs handling where pscsi_plugin_task has
 602          * not been allocated because TCM is handling the emulation directly.
 603          */
 604         if (!pt)
 605                 return;
 606
 607         cdb = &pt->pscsi_cdb[0];
 608         /*
 609          * Hack to make sure that Write-Protect modepage is set if R/O mode is
 610          * forced.
 611          */
 612         if (!cmd->data_length)
 613                 goto after_mode_sense;
 614
 615         if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
 616             scsi_status == SAM_STAT_GOOD) {
 617                 bool read_only = target_lun_is_rdonly(cmd);
 618
 619                 if (read_only) {
 620                         unsigned char *buf;
 621
 622                         buf = transport_kmap_data_sg(cmd);
 623                         if (!buf) {
 624                                 ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
 625                         }
 626
 627                         if (cdb[0] == MODE_SENSE_10) {
 628                                 if (!(buf[3] & 0x80))
 629                                         buf[3] |= 0x80;
 630                         } else {
 631                                 if (!(buf[2] & 0x80))
 632                                         buf[2] |= 0x80;
 633                         }
 634
 635                         transport_kunmap_data_sg(cmd);
 636                 }
 637         }
 638 after_mode_sense:
 639
 640         if (sd->type != TYPE_TAPE || !cmd->data_length)
 641                 goto after_mode_select;
 642
 643         /*
 644          * Hack to correctly obtain the initiator requested blocksize for
 645          * TYPE_TAPE.  Since this value is dependent upon each tape media,
 646          * struct scsi_device->sector_size will not contain the correct value
 647          * by default, so we go ahead and set it so
 648          * TRANSPORT(dev)->get_blockdev() returns the correct value to the
 649          * storage engine.
 650          */
 651         if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
 652              scsi_status == SAM_STAT_GOOD) {
 653                 unsigned char *buf;
 654                 u16 bdl;
 655                 u32 blocksize;
 656
 657                 buf = sg_virt(&cmd->t_data_sg[0]);
 658                 if (!buf) {
 659                         pr_err("Unable to get buf for scatterlist\n");
 660                         goto after_mode_select;
 661                 }
 662
 663                 if (cdb[0] == MODE_SELECT)
 664                         bdl = buf[3];
 665                 else
 666                         bdl = get_unaligned_be16(&buf[6]);
 667
 668                 if (!bdl)
 669                         goto after_mode_select;
 670
 671                 if (cdb[0] == MODE_SELECT)
 672                         blocksize = get_unaligned_be24(&buf[9]);
 673                 else
 674                         blocksize = get_unaligned_be24(&buf[13]);
 675
 676                 sd->sector_size = blocksize;
 677         }
 678 after_mode_select:
 679
 680         if (scsi_status == SAM_STAT_CHECK_CONDITION) {
 681                 transport_copy_sense_to_cmd(cmd, req_sense);
 682
 683                 /*
 684                  * check for TAPE device reads with
 685                  * FM/EOM/ILI set, so that we can get data
 686                  * back despite framework assumption that a
 687                  * check condition means there is no data
 688                  */
 689                 if (sd->type == TYPE_TAPE &&
 690                     cmd->data_direction == DMA_FROM_DEVICE) {
 691                         /*
 692                          * is sense data valid, fixed format,
 693                          * and have FM, EOM, or ILI set?
 694                          */
 695                         if (req_sense[0] == 0xf0 &&     /* valid, fixed format */
 696                             req_sense[2] & 0xe0 &&      /* FM, EOM, or ILI */
 697                             (req_sense[2] & 0xf) == 0) { /* key==NO_SENSE */
 698                                 pr_debug("Tape FM/EOM/ILI status detected. Treat as normal read.\n");
 699                                 cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL;
 700                         }
 701                 }
 702         }
 703 }
 704
 705 enum {
 706         Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
 707         Opt_scsi_lun_id, Opt_err
 708 };
 709
 710 static match_table_t tokens = {
 711         {Opt_scsi_host_id, "scsi_host_id=%d"},
 712         {Opt_scsi_channel_id, "scsi_channel_id=%d"},
 713         {Opt_scsi_target_id, "scsi_target_id=%d"},
 714         {Opt_scsi_lun_id, "scsi_lun_id=%d"},
 715         {Opt_err, NULL}
 716 };
 717
 718 static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
 719                 const char *page, ssize_t count)
 720 {
 721         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 722         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 723         char *orig, *ptr, *opts;
 724         substring_t args[MAX_OPT_ARGS];
 725         int ret = 0, arg, token;
 726
 727         opts = kstrdup(page, GFP_KERNEL);
 728         if (!opts)
 729                 return -ENOMEM;
 730
 731         orig = opts;
 732
 733         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 734                 if (!*ptr)
 735                         continue;
 736
 737                 token = match_token(ptr, tokens, args);
 738                 switch (token) {
 739                 case Opt_scsi_host_id:
 740                         if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 741                                 pr_err("PSCSI[%d]: Unable to accept"
 742                                         " scsi_host_id while phv_mode =="
 743                                         " PHV_LLD_SCSI_HOST_NO\n",
 744                                         phv->phv_host_id);
 745                                 ret = -EINVAL;
 746                                 goto out;
 747                         }
 748                         ret = match_int(args, &arg);
 749                         if (ret)
 750                                 goto out;
 751                         pdv->pdv_host_id = arg;
 752                         pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
 753                                 " %d\n", phv->phv_host_id, pdv->pdv_host_id);
 754                         pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
 755                         break;
 756                 case Opt_scsi_channel_id:
 757                         ret = match_int(args, &arg);
 758                         if (ret)
 759                                 goto out;
 760                         pdv->pdv_channel_id = arg;
 761                         pr_debug("PSCSI[%d]: Referencing SCSI Channel"
 762                                 " ID: %d\n",  phv->phv_host_id,
 763                                 pdv->pdv_channel_id);
 764                         pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
 765                         break;
 766                 case Opt_scsi_target_id:
 767                         ret = match_int(args, &arg);
 768                         if (ret)
 769                                 goto out;
 770                         pdv->pdv_target_id = arg;
 771                         pr_debug("PSCSI[%d]: Referencing SCSI Target"
 772                                 " ID: %d\n", phv->phv_host_id,
 773                                 pdv->pdv_target_id);
 774                         pdv->pdv_flags |= PDF_HAS_TARGET_ID;
 775                         break;
 776                 case Opt_scsi_lun_id:
 777                         ret = match_int(args, &arg);
 778                         if (ret)
 779                                 goto out;
 780                         pdv->pdv_lun_id = arg;
 781                         pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
 782                                 " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
 783                         pdv->pdv_flags |= PDF_HAS_LUN_ID;
 784                         break;
 785                 default:
 786                         break;
 787                 }
 788         }
 789
 790 out:
 791         kfree(orig);
 792         return (!ret) ? count : ret;
 793 }
 794
 795 static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
 796 {
 797         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 798         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 799         struct scsi_device *sd = pdv->pdv_sd;
 800         unsigned char host_id[16];
 801         ssize_t bl;
 802
 803         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 804                 snprintf(host_id, 16, "%d", pdv->pdv_host_id);
 805         else
 806                 snprintf(host_id, 16, "PHBA Mode");
 807
 808         bl = sprintf(b, "SCSI Device Bus Location:"
 809                 " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
 810                 pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
 811                 host_id);
 812
 813         if (sd) {
 814                 bl += sprintf(b + bl, "        Vendor: %."
 815                         __stringify(INQUIRY_VENDOR_LEN) "s", sd->vendor);
 816                 bl += sprintf(b + bl, " Model: %."
 817                         __stringify(INQUIRY_MODEL_LEN) "s", sd->model);
 818                 bl += sprintf(b + bl, " Rev: %."
 819                         __stringify(INQUIRY_REVISION_LEN) "s\n", sd->rev);
 820         }
 821         return bl;
 822 }
 823
 824 static void pscsi_bi_endio(struct bio *bio)
 825 {
 826         bio_put(bio);
 827 }
 828
 829 static inline struct bio *pscsi_get_bio(int nr_vecs)
 830 {
 831         struct bio *bio;
 832         /*
 833          * Use bio_malloc() following the comment in for bio -> struct request
 834          * in block/blk-core.c:blk_make_request()
 835          */
 836         bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
 837         if (!bio) {
 838                 pr_err("PSCSI: bio_kmalloc() failed\n");
 839                 return NULL;
 840         }
 841         bio->bi_end_io = pscsi_bi_endio;
 842
 843         return bio;
 844 }
 845
 846 static sense_reason_t
 847 pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 848                 struct request *req)
 849 {
 850         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 851         struct bio *bio = NULL;
 852         struct page *page;
 853         struct scatterlist *sg;
 854         u32 data_len = cmd->data_length, i, len, bytes, off;
 855         int nr_pages = (cmd->data_length + sgl[0].offset +
 856                         PAGE_SIZE - 1) >> PAGE_SHIFT;
 857         int nr_vecs = 0, rc;
 858         int rw = (cmd->data_direction == DMA_TO_DEVICE);
 859
 860         BUG_ON(!cmd->data_length);
 861
 862         pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
 863
 864         for_each_sg(sgl, sg, sgl_nents, i) {
 865                 page = sg_page(sg);
 866                 off = sg->offset;
 867                 len = sg->length;
 868
 869                 pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
 870                         page, len, off);
 871
 872                 /*
 873                  * We only have one page of data in each sg element,
 874                  * we can not cross a page boundary.
 875                  */
 876                 if (off + len > PAGE_SIZE)
 877                         goto fail;
 878
 879                 if (len > 0 && data_len > 0) {
 880                         bytes = min_t(unsigned int, len, PAGE_SIZE - off);
 881                         bytes = min(bytes, data_len);
 882
 883                         if (!bio) {
 884 new_bio:
 885                                 nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
 886                                 nr_pages -= nr_vecs;
 887                                 /*
 888                                  * Calls bio_kmalloc() and sets bio->bi_end_io()
 889                                  */
 890                                 bio = pscsi_get_bio(nr_vecs);
 891                                 if (!bio)
 892                                         goto fail;
 893
 894                                 if (rw)
 895                                         bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
 896
 897                                 pr_debug("PSCSI: Allocated bio: %p,"
 898                                         " dir: %s nr_vecs: %d\n", bio,
 899                                         (rw) ? "rw" : "r", nr_vecs);
 900                         }
 901
 902                         pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
 903                                 " bio: %p page: %p len: %d off: %d\n", i, bio,
 904                                 page, len, off);
 905
 906                         rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
 907                                         bio, page, bytes, off);
 908                         pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
 909                                 bio_segments(bio), nr_vecs);
 910                         if (rc != bytes) {
 911                                 pr_debug("PSCSI: Reached bio->bi_vcnt max:"
 912                                         " %d i: %d bio: %p, allocating another"
 913                                         " bio\n", bio->bi_vcnt, i, bio);
 914
 915                                 rc = blk_rq_append_bio(req, &bio);
 916                                 if (rc) {
 917                                         pr_err("pSCSI: failed to append bio\n");
 918                                         goto fail;
 919                                 }
 920
 921                                 /*
 922                                  * Clear the pointer so that another bio will
 923                                  * be allocated with pscsi_get_bio() above.
 924                                  */
 925                                 bio = NULL;
 926                                 goto new_bio;
 927                         }
 928
 929                         data_len -= bytes;
 930                 }
 931         }
 932
 933         if (bio) {
 934                 rc = blk_rq_append_bio(req, &bio);
 935                 if (rc) {
 936                         pr_err("pSCSI: failed to append bio\n");
 937                         goto fail;
 938                 }
 939         }
 940
 941         return 0;
 942 fail:
 943         if (bio)
 944                 bio_put(bio);
 945         while (req->bio) {
 946                 bio = req->bio;
 947                 req->bio = bio->bi_next;
 948                 bio_put(bio);
 949         }
 950         req->biotail = NULL;
 951         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 952 }
 953
 954 static sense_reason_t
 955 pscsi_parse_cdb(struct se_cmd *cmd)
 956 {
 957         if (cmd->se_cmd_flags & SCF_BIDI)
 958                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 959
 960         return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
 961 }
 962
 963 static sense_reason_t
 964 pscsi_execute_cmd(struct se_cmd *cmd)
 965 {
 966         struct scatterlist *sgl = cmd->t_data_sg;
 967         u32 sgl_nents = cmd->t_data_nents;
 968         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 969         struct pscsi_plugin_task *pt;
 970         struct request *req;
 971         sense_reason_t ret;
 972
 973         /*
 974          * Dynamically alloc cdb space, since it may be larger than
 975          * TCM_MAX_COMMAND_SIZE
 976          */
 977         pt = kzalloc(sizeof(*pt) + scsi_command_size(cmd->t_task_cdb), GFP_KERNEL);
 978         if (!pt) {
 979                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 980         }
 981         cmd->priv = pt;
 982
 983         memcpy(pt->pscsi_cdb, cmd->t_task_cdb,
 984                 scsi_command_size(cmd->t_task_cdb));
 985
 986         req = blk_get_request(pdv->pdv_sd->request_queue,
 987                         cmd->data_direction == DMA_TO_DEVICE ?
 988                         REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
 989         if (IS_ERR(req)) {
 990                 pr_err("PSCSI: blk_get_request() failed\n");
 991                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 992                 goto fail;
 993         }
 994
 995         if (sgl) {
 996                 ret = pscsi_map_sg(cmd, sgl, sgl_nents, req);
 997                 if (ret)
 998                         goto fail_put_request;
 999         }
1000
1001         req->end_io = pscsi_req_done;
1002         req->end_io_data = cmd;
1003         scsi_req(req)->cmd_len = scsi_command_size(pt->pscsi_cdb);
1004         scsi_req(req)->cmd = &pt->pscsi_cdb[0];
1005         if (pdv->pdv_sd->type == TYPE_DISK ||
1006             pdv->pdv_sd->type == TYPE_ZBC)
1007                 req->timeout = PS_TIMEOUT_DISK;
1008         else
1009                 req->timeout = PS_TIMEOUT_OTHER;
1010         scsi_req(req)->retries = PS_RETRY;
1011
1012         blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL, req,
1013                         (cmd->sam_task_attr == TCM_HEAD_TAG),
1014                         pscsi_req_done);
1015
1016         return 0;
1017
1018 fail_put_request:
1019         blk_put_request(req);
1020 fail:
1021         kfree(pt);
1022         return ret;
1023 }
1024
1025 /*      pscsi_get_device_type():
1026  *
1027  *
1028  */
1029 static u32 pscsi_get_device_type(struct se_device *dev)
1030 {
1031         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1032         struct scsi_device *sd = pdv->pdv_sd;
1033
1034         return (sd) ? sd->type : TYPE_NO_LUN;
1035 }
1036
1037 static sector_t pscsi_get_blocks(struct se_device *dev)
1038 {
1039         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1040
1041         if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
1042                 return pdv->pdv_bd->bd_part->nr_sects;
1043
1044         return 0;
1045 }
1046
1047 static void pscsi_req_done(struct request *req, blk_status_t status)
1048 {
1049         struct se_cmd *cmd = req->end_io_data;
1050         struct pscsi_plugin_task *pt = cmd->priv;
1051         int result = scsi_req(req)->result;
1052         u8 scsi_status = status_byte(result) << 1;
1053
1054         if (scsi_status) {
1055                 pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1056                         " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1057                         result);
1058         }
1059
1060         pscsi_complete_cmd(cmd, scsi_status, scsi_req(req)->sense);
1061
1062         switch (host_byte(result)) {
1063         case DID_OK:
1064                 target_complete_cmd_with_length(cmd, scsi_status,
1065                         cmd->data_length - scsi_req(req)->resid_len);
1066                 break;
1067         default:
1068                 pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1069                         " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1070                         result);
1071                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1072                 break;
1073         }
1074
1075         blk_put_request(req);
1076         kfree(pt);
1077 }
1078
1079 static const struct target_backend_ops pscsi_ops = {
1080         .name                   = "pscsi",
1081         .owner                  = THIS_MODULE,
1082         .transport_flags_default = TRANSPORT_FLAG_PASSTHROUGH |
1083                                    TRANSPORT_FLAG_PASSTHROUGH_ALUA |
1084                                    TRANSPORT_FLAG_PASSTHROUGH_PGR,
1085         .attach_hba             = pscsi_attach_hba,
1086         .detach_hba             = pscsi_detach_hba,
1087         .pmode_enable_hba       = pscsi_pmode_enable_hba,
1088         .alloc_device           = pscsi_alloc_device,
1089         .configure_device       = pscsi_configure_device,
1090         .destroy_device         = pscsi_destroy_device,
1091         .free_device            = pscsi_free_device,
1092         .parse_cdb              = pscsi_parse_cdb,
1093         .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1094         .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1095         .get_device_type        = pscsi_get_device_type,
1096         .get_blocks             = pscsi_get_blocks,
1097         .tb_dev_attrib_attrs    = passthrough_attrib_attrs,
1098 };
1099
1100 static int __init pscsi_module_init(void)
1101 {
1102         return transport_backend_register(&pscsi_ops);
1103 }
1104
1105 static void __exit pscsi_module_exit(void)
1106 {
1107         target_backend_unregister(&pscsi_ops);
1108 }
1109
1110 MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1111 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1112 MODULE_LICENSE("GPL");
1113
1114 module_init(pscsi_module_init);
1115 module_exit(pscsi_module_exit);