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