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, BLK_OPEN_WRITE | BLK_OPEN_READ,
 370                                 pdv, NULL);
 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, pdv);
 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, pdv);
 569                         pdv->pdv_bd = NULL;
 570                 }
 571                 /*
 572                  * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
 573                  * to struct Scsi_Host now.
 574                  */
 575                 if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
 576                     (phv->phv_lld_host != NULL))
 577                         scsi_host_put(phv->phv_lld_host);
 578                 else if (pdv->pdv_lld_host)
 579                         scsi_host_put(pdv->pdv_lld_host);
 580
 581                 scsi_device_put(sd);
 582
 583                 pdv->pdv_sd = NULL;
 584         }
 585 }
 586
 587 static void pscsi_complete_cmd(struct se_cmd *cmd, u8 scsi_status,
 588                                unsigned char *req_sense, int valid_data)
 589 {
 590         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 591         struct scsi_device *sd = pdv->pdv_sd;
 592         unsigned char *cdb = cmd->priv;
 593
 594         /*
 595          * Special case for REPORT_LUNs which is emulated and not passed on.
 596          */
 597         if (!cdb)
 598                 return;
 599
 600         /*
 601          * Hack to make sure that Write-Protect modepage is set if R/O mode is
 602          * forced.
 603          */
 604         if (!cmd->data_length)
 605                 goto after_mode_sense;
 606
 607         if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
 608             scsi_status == SAM_STAT_GOOD) {
 609                 bool read_only = target_lun_is_rdonly(cmd);
 610
 611                 if (read_only) {
 612                         unsigned char *buf;
 613
 614                         buf = transport_kmap_data_sg(cmd);
 615                         if (!buf) {
 616                                 ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
 617                         } else {
 618                                 if (cdb[0] == MODE_SENSE_10) {
 619                                         if (!(buf[3] & 0x80))
 620                                                 buf[3] |= 0x80;
 621                                 } else {
 622                                         if (!(buf[2] & 0x80))
 623                                                 buf[2] |= 0x80;
 624                                 }
 625
 626                                 transport_kunmap_data_sg(cmd);
 627                         }
 628                 }
 629         }
 630 after_mode_sense:
 631
 632         if (sd->type != TYPE_TAPE || !cmd->data_length)
 633                 goto after_mode_select;
 634
 635         /*
 636          * Hack to correctly obtain the initiator requested blocksize for
 637          * TYPE_TAPE.  Since this value is dependent upon each tape media,
 638          * struct scsi_device->sector_size will not contain the correct value
 639          * by default, so we go ahead and set it so
 640          * TRANSPORT(dev)->get_blockdev() returns the correct value to the
 641          * storage engine.
 642          */
 643         if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
 644              scsi_status == SAM_STAT_GOOD) {
 645                 unsigned char *buf;
 646                 u16 bdl;
 647                 u32 blocksize;
 648
 649                 buf = sg_virt(&cmd->t_data_sg[0]);
 650                 if (!buf) {
 651                         pr_err("Unable to get buf for scatterlist\n");
 652                         goto after_mode_select;
 653                 }
 654
 655                 if (cdb[0] == MODE_SELECT)
 656                         bdl = buf[3];
 657                 else
 658                         bdl = get_unaligned_be16(&buf[6]);
 659
 660                 if (!bdl)
 661                         goto after_mode_select;
 662
 663                 if (cdb[0] == MODE_SELECT)
 664                         blocksize = get_unaligned_be24(&buf[9]);
 665                 else
 666                         blocksize = get_unaligned_be24(&buf[13]);
 667
 668                 sd->sector_size = blocksize;
 669         }
 670 after_mode_select:
 671
 672         if (scsi_status == SAM_STAT_CHECK_CONDITION) {
 673                 transport_copy_sense_to_cmd(cmd, req_sense);
 674
 675                 /*
 676                  * check for TAPE device reads with
 677                  * FM/EOM/ILI set, so that we can get data
 678                  * back despite framework assumption that a
 679                  * check condition means there is no data
 680                  */
 681                 if (sd->type == TYPE_TAPE && valid_data &&
 682                     cmd->data_direction == DMA_FROM_DEVICE) {
 683                         /*
 684                          * is sense data valid, fixed format,
 685                          * and have FM, EOM, or ILI set?
 686                          */
 687                         if (req_sense[0] == 0xf0 &&     /* valid, fixed format */
 688                             req_sense[2] & 0xe0 &&      /* FM, EOM, or ILI */
 689                             (req_sense[2] & 0xf) == 0) { /* key==NO_SENSE */
 690                                 pr_debug("Tape FM/EOM/ILI status detected. Treat as normal read.\n");
 691                                 cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL;
 692                         }
 693                 }
 694         }
 695 }
 696
 697 enum {
 698         Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
 699         Opt_scsi_lun_id, Opt_err
 700 };
 701
 702 static match_table_t tokens = {
 703         {Opt_scsi_host_id, "scsi_host_id=%d"},
 704         {Opt_scsi_channel_id, "scsi_channel_id=%d"},
 705         {Opt_scsi_target_id, "scsi_target_id=%d"},
 706         {Opt_scsi_lun_id, "scsi_lun_id=%d"},
 707         {Opt_err, NULL}
 708 };
 709
 710 static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
 711                 const char *page, ssize_t count)
 712 {
 713         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 714         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 715         char *orig, *ptr, *opts;
 716         substring_t args[MAX_OPT_ARGS];
 717         int ret = 0, arg, token;
 718
 719         opts = kstrdup(page, GFP_KERNEL);
 720         if (!opts)
 721                 return -ENOMEM;
 722
 723         orig = opts;
 724
 725         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 726                 if (!*ptr)
 727                         continue;
 728
 729                 token = match_token(ptr, tokens, args);
 730                 switch (token) {
 731                 case Opt_scsi_host_id:
 732                         if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 733                                 pr_err("PSCSI[%d]: Unable to accept"
 734                                         " scsi_host_id while phv_mode =="
 735                                         " PHV_LLD_SCSI_HOST_NO\n",
 736                                         phv->phv_host_id);
 737                                 ret = -EINVAL;
 738                                 goto out;
 739                         }
 740                         ret = match_int(args, &arg);
 741                         if (ret)
 742                                 goto out;
 743                         pdv->pdv_host_id = arg;
 744                         pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
 745                                 " %d\n", phv->phv_host_id, pdv->pdv_host_id);
 746                         pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
 747                         break;
 748                 case Opt_scsi_channel_id:
 749                         ret = match_int(args, &arg);
 750                         if (ret)
 751                                 goto out;
 752                         pdv->pdv_channel_id = arg;
 753                         pr_debug("PSCSI[%d]: Referencing SCSI Channel"
 754                                 " ID: %d\n",  phv->phv_host_id,
 755                                 pdv->pdv_channel_id);
 756                         pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
 757                         break;
 758                 case Opt_scsi_target_id:
 759                         ret = match_int(args, &arg);
 760                         if (ret)
 761                                 goto out;
 762                         pdv->pdv_target_id = arg;
 763                         pr_debug("PSCSI[%d]: Referencing SCSI Target"
 764                                 " ID: %d\n", phv->phv_host_id,
 765                                 pdv->pdv_target_id);
 766                         pdv->pdv_flags |= PDF_HAS_TARGET_ID;
 767                         break;
 768                 case Opt_scsi_lun_id:
 769                         ret = match_int(args, &arg);
 770                         if (ret)
 771                                 goto out;
 772                         pdv->pdv_lun_id = arg;
 773                         pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
 774                                 " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
 775                         pdv->pdv_flags |= PDF_HAS_LUN_ID;
 776                         break;
 777                 default:
 778                         break;
 779                 }
 780         }
 781
 782 out:
 783         kfree(orig);
 784         return (!ret) ? count : ret;
 785 }
 786
 787 static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
 788 {
 789         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 790         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 791         struct scsi_device *sd = pdv->pdv_sd;
 792         unsigned char host_id[16];
 793         ssize_t bl;
 794
 795         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 796                 snprintf(host_id, 16, "%d", pdv->pdv_host_id);
 797         else
 798                 snprintf(host_id, 16, "PHBA Mode");
 799
 800         bl = sprintf(b, "SCSI Device Bus Location:"
 801                 " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
 802                 pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
 803                 host_id);
 804
 805         if (sd) {
 806                 bl += sprintf(b + bl, "        Vendor: %."
 807                         __stringify(INQUIRY_VENDOR_LEN) "s", sd->vendor);
 808                 bl += sprintf(b + bl, " Model: %."
 809                         __stringify(INQUIRY_MODEL_LEN) "s", sd->model);
 810                 bl += sprintf(b + bl, " Rev: %."
 811                         __stringify(INQUIRY_REVISION_LEN) "s\n", sd->rev);
 812         }
 813         return bl;
 814 }
 815
 816 static void pscsi_bi_endio(struct bio *bio)
 817 {
 818         bio_uninit(bio);
 819         kfree(bio);
 820 }
 821
 822 static sense_reason_t
 823 pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 824                 struct request *req)
 825 {
 826         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 827         struct bio *bio = NULL;
 828         struct page *page;
 829         struct scatterlist *sg;
 830         u32 data_len = cmd->data_length, i, len, bytes, off;
 831         int nr_pages = (cmd->data_length + sgl[0].offset +
 832                         PAGE_SIZE - 1) >> PAGE_SHIFT;
 833         int nr_vecs = 0, rc;
 834         int rw = (cmd->data_direction == DMA_TO_DEVICE);
 835
 836         BUG_ON(!cmd->data_length);
 837
 838         pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
 839
 840         for_each_sg(sgl, sg, sgl_nents, i) {
 841                 page = sg_page(sg);
 842                 off = sg->offset;
 843                 len = sg->length;
 844
 845                 pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
 846                         page, len, off);
 847
 848                 /*
 849                  * We only have one page of data in each sg element,
 850                  * we can not cross a page boundary.
 851                  */
 852                 if (off + len > PAGE_SIZE)
 853                         goto fail;
 854
 855                 if (len > 0 && data_len > 0) {
 856                         bytes = min_t(unsigned int, len, PAGE_SIZE - off);
 857                         bytes = min(bytes, data_len);
 858
 859                         if (!bio) {
 860 new_bio:
 861                                 nr_vecs = bio_max_segs(nr_pages);
 862                                 bio = bio_kmalloc(nr_vecs, GFP_KERNEL);
 863                                 if (!bio)
 864                                         goto fail;
 865                                 bio_init(bio, NULL, bio->bi_inline_vecs, nr_vecs,
 866                                          rw ? REQ_OP_WRITE : REQ_OP_READ);
 867                                 bio->bi_end_io = pscsi_bi_endio;
 868
 869                                 pr_debug("PSCSI: Allocated bio: %p,"
 870                                         " dir: %s nr_vecs: %d\n", bio,
 871                                         (rw) ? "rw" : "r", nr_vecs);
 872                         }
 873
 874                         pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
 875                                 " bio: %p page: %p len: %d off: %d\n", i, bio,
 876                                 page, len, off);
 877
 878                         rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
 879                                         bio, page, bytes, off);
 880                         pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
 881                                 bio_segments(bio), nr_vecs);
 882                         if (rc != bytes) {
 883                                 pr_debug("PSCSI: Reached bio->bi_vcnt max:"
 884                                         " %d i: %d bio: %p, allocating another"
 885                                         " bio\n", bio->bi_vcnt, i, bio);
 886
 887                                 rc = blk_rq_append_bio(req, bio);
 888                                 if (rc) {
 889                                         pr_err("pSCSI: failed to append bio\n");
 890                                         goto fail;
 891                                 }
 892
 893                                 goto new_bio;
 894                         }
 895
 896                         data_len -= bytes;
 897                 }
 898         }
 899
 900         if (bio) {
 901                 rc = blk_rq_append_bio(req, bio);
 902                 if (rc) {
 903                         pr_err("pSCSI: failed to append bio\n");
 904                         goto fail;
 905                 }
 906         }
 907
 908         return 0;
 909 fail:
 910         if (bio)
 911                 bio_put(bio);
 912         while (req->bio) {
 913                 bio = req->bio;
 914                 req->bio = bio->bi_next;
 915                 bio_put(bio);
 916         }
 917         req->biotail = NULL;
 918         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 919 }
 920
 921 static sense_reason_t
 922 pscsi_parse_cdb(struct se_cmd *cmd)
 923 {
 924         if (cmd->se_cmd_flags & SCF_BIDI)
 925                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 926
 927         return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
 928 }
 929
 930 static sense_reason_t
 931 pscsi_execute_cmd(struct se_cmd *cmd)
 932 {
 933         struct scatterlist *sgl = cmd->t_data_sg;
 934         u32 sgl_nents = cmd->t_data_nents;
 935         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 936         struct scsi_cmnd *scmd;
 937         struct request *req;
 938         sense_reason_t ret;
 939
 940         req = scsi_alloc_request(pdv->pdv_sd->request_queue,
 941                         cmd->data_direction == DMA_TO_DEVICE ?
 942                         REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
 943         if (IS_ERR(req))
 944                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 945
 946         if (sgl) {
 947                 ret = pscsi_map_sg(cmd, sgl, sgl_nents, req);
 948                 if (ret)
 949                         goto fail_put_request;
 950         }
 951
 952         req->end_io = pscsi_req_done;
 953         req->end_io_data = cmd;
 954
 955         scmd = blk_mq_rq_to_pdu(req);
 956         scmd->cmd_len = scsi_command_size(cmd->t_task_cdb);
 957         if (scmd->cmd_len > sizeof(scmd->cmnd)) {
 958                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 959                 goto fail_put_request;
 960         }
 961         memcpy(scmd->cmnd, cmd->t_task_cdb, scmd->cmd_len);
 962
 963         if (pdv->pdv_sd->type == TYPE_DISK ||
 964             pdv->pdv_sd->type == TYPE_ZBC)
 965                 req->timeout = PS_TIMEOUT_DISK;
 966         else
 967                 req->timeout = PS_TIMEOUT_OTHER;
 968         scmd->allowed = PS_RETRY;
 969
 970         cmd->priv = scmd->cmnd;
 971
 972         blk_execute_rq_nowait(req, cmd->sam_task_attr == TCM_HEAD_TAG);
 973
 974         return 0;
 975
 976 fail_put_request:
 977         blk_mq_free_request(req);
 978         return ret;
 979 }
 980
 981 /*      pscsi_get_device_type():
 982  *
 983  *
 984  */
 985 static u32 pscsi_get_device_type(struct se_device *dev)
 986 {
 987         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 988         struct scsi_device *sd = pdv->pdv_sd;
 989
 990         return (sd) ? sd->type : TYPE_NO_LUN;
 991 }
 992
 993 static sector_t pscsi_get_blocks(struct se_device *dev)
 994 {
 995         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 996
 997         if (pdv->pdv_bd)
 998                 return bdev_nr_sectors(pdv->pdv_bd);
 999         return 0;
1000 }
1001
1002 static enum rq_end_io_ret pscsi_req_done(struct request *req,
1003                                          blk_status_t status)
1004 {
1005         struct se_cmd *cmd = req->end_io_data;
1006         struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
1007         enum sam_status scsi_status = scmd->result & 0xff;
1008         int valid_data = cmd->data_length - scmd->resid_len;
1009         u8 *cdb = cmd->priv;
1010
1011         if (scsi_status != SAM_STAT_GOOD) {
1012                 pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1013                         " 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
1014         }
1015
1016         pscsi_complete_cmd(cmd, scsi_status, scmd->sense_buffer, valid_data);
1017
1018         switch (host_byte(scmd->result)) {
1019         case DID_OK:
1020                 target_complete_cmd_with_length(cmd, scsi_status, valid_data);
1021                 break;
1022         default:
1023                 pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1024                         " 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
1025                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1026                 break;
1027         }
1028
1029         blk_mq_free_request(req);
1030         return RQ_END_IO_NONE;
1031 }
1032
1033 static const struct target_backend_ops pscsi_ops = {
1034         .name                   = "pscsi",
1035         .owner                  = THIS_MODULE,
1036         .transport_flags_default = TRANSPORT_FLAG_PASSTHROUGH |
1037                                    TRANSPORT_FLAG_PASSTHROUGH_ALUA |
1038                                    TRANSPORT_FLAG_PASSTHROUGH_PGR,
1039         .attach_hba             = pscsi_attach_hba,
1040         .detach_hba             = pscsi_detach_hba,
1041         .pmode_enable_hba       = pscsi_pmode_enable_hba,
1042         .alloc_device           = pscsi_alloc_device,
1043         .configure_device       = pscsi_configure_device,
1044         .destroy_device         = pscsi_destroy_device,
1045         .free_device            = pscsi_free_device,
1046         .parse_cdb              = pscsi_parse_cdb,
1047         .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1048         .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1049         .get_device_type        = pscsi_get_device_type,
1050         .get_blocks             = pscsi_get_blocks,
1051         .tb_dev_attrib_attrs    = passthrough_attrib_attrs,
1052 };
1053
1054 static int __init pscsi_module_init(void)
1055 {
1056         return transport_backend_register(&pscsi_ops);
1057 }
1058
1059 static void __exit pscsi_module_exit(void)
1060 {
1061         target_backend_unregister(&pscsi_ops);
1062 }
1063
1064 MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1065 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1066 MODULE_LICENSE("GPL");
1067
1068 module_init(pscsi_module_init);
1069 module_exit(pscsi_module_exit);