drivers/target/target_core_pscsi.c

   1 /*******************************************************************************
   2  * Filename:  target_core_pscsi.c
   3  *
   4  * This file contains the generic target mode <-> Linux SCSI subsystem plugin.
   5  *
   6  * (c) Copyright 2003-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/string.h>
  27 #include <linux/parser.h>
  28 #include <linux/timer.h>
  29 #include <linux/blkdev.h>
  30 #include <linux/blk_types.h>
  31 #include <linux/slab.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/genhd.h>
  34 #include <linux/cdrom.h>
  35 #include <linux/ratelimit.h>
  36 #include <linux/module.h>
  37 #include <asm/unaligned.h>
  38
  39 #include <scsi/scsi_device.h>
  40 #include <scsi/scsi_host.h>
  41 #include <scsi/scsi_tcq.h>
  42
  43 #include <target/target_core_base.h>
  44 #include <target/target_core_backend.h>
  45 #include <target/target_core_backend_configfs.h>
  46
  47 #include "target_core_alua.h"
  48 #include "target_core_pscsi.h"
  49
  50 #define ISPRINT(a)  ((a >= ' ') && (a <= '~'))
  51
  52 static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
  53 {
  54         return container_of(dev, struct pscsi_dev_virt, dev);
  55 }
  56
  57 static struct se_subsystem_api pscsi_template;
  58
  59 static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
  60 static void pscsi_req_done(struct request *, int);
  61
  62 /*      pscsi_attach_hba():
  63  *
  64  *      pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
  65  *      from the passed SCSI Host ID.
  66  */
  67 static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
  68 {
  69         struct pscsi_hba_virt *phv;
  70
  71         phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
  72         if (!phv) {
  73                 pr_err("Unable to allocate struct pscsi_hba_virt\n");
  74                 return -ENOMEM;
  75         }
  76         phv->phv_host_id = host_id;
  77         phv->phv_mode = PHV_VIRTUAL_HOST_ID;
  78
  79         hba->hba_ptr = phv;
  80
  81         pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
  82                 " Generic Target Core Stack %s\n", hba->hba_id,
  83                 PSCSI_VERSION, TARGET_CORE_MOD_VERSION);
  84         pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
  85                hba->hba_id);
  86
  87         return 0;
  88 }
  89
  90 static void pscsi_detach_hba(struct se_hba *hba)
  91 {
  92         struct pscsi_hba_virt *phv = hba->hba_ptr;
  93         struct Scsi_Host *scsi_host = phv->phv_lld_host;
  94
  95         if (scsi_host) {
  96                 scsi_host_put(scsi_host);
  97
  98                 pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
  99                         " Generic Target Core\n", hba->hba_id,
 100                         (scsi_host->hostt->name) ? (scsi_host->hostt->name) :
 101                         "Unknown");
 102         } else
 103                 pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
 104                         " from Generic Target Core\n", hba->hba_id);
 105
 106         kfree(phv);
 107         hba->hba_ptr = NULL;
 108 }
 109
 110 static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
 111 {
 112         struct pscsi_hba_virt *phv = hba->hba_ptr;
 113         struct Scsi_Host *sh = phv->phv_lld_host;
 114         /*
 115          * Release the struct Scsi_Host
 116          */
 117         if (!mode_flag) {
 118                 if (!sh)
 119                         return 0;
 120
 121                 phv->phv_lld_host = NULL;
 122                 phv->phv_mode = PHV_VIRTUAL_HOST_ID;
 123
 124                 pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
 125                         " %s\n", hba->hba_id, (sh->hostt->name) ?
 126                         (sh->hostt->name) : "Unknown");
 127
 128                 scsi_host_put(sh);
 129                 return 0;
 130         }
 131         /*
 132          * Otherwise, locate struct Scsi_Host from the original passed
 133          * pSCSI Host ID and enable for phba mode
 134          */
 135         sh = scsi_host_lookup(phv->phv_host_id);
 136         if (!sh) {
 137                 pr_err("pSCSI: Unable to locate SCSI Host for"
 138                         " phv_host_id: %d\n", phv->phv_host_id);
 139                 return -EINVAL;
 140         }
 141
 142         phv->phv_lld_host = sh;
 143         phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
 144
 145         pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
 146                 hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
 147
 148         return 1;
 149 }
 150
 151 static void pscsi_tape_read_blocksize(struct se_device *dev,
 152                 struct scsi_device *sdev)
 153 {
 154         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 155         int ret;
 156
 157         buf = kzalloc(12, GFP_KERNEL);
 158         if (!buf)
 159                 return;
 160
 161         memset(cdb, 0, MAX_COMMAND_SIZE);
 162         cdb[0] = MODE_SENSE;
 163         cdb[4] = 0x0c; /* 12 bytes */
 164
 165         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
 166                         HZ, 1, NULL);
 167         if (ret)
 168                 goto out_free;
 169
 170         /*
 171          * If MODE_SENSE still returns zero, set the default value to 1024.
 172          */
 173         sdev->sector_size = (buf[9] << 16) | (buf[10] << 8) | (buf[11]);
 174         if (!sdev->sector_size)
 175                 sdev->sector_size = 1024;
 176 out_free:
 177         kfree(buf);
 178 }
 179
 180 static void
 181 pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
 182 {
 183         unsigned char *buf;
 184
 185         if (sdev->inquiry_len < INQUIRY_LEN)
 186                 return;
 187
 188         buf = sdev->inquiry;
 189         if (!buf)
 190                 return;
 191         /*
 192          * Use sdev->inquiry from drivers/scsi/scsi_scan.c:scsi_alloc_sdev()
 193          */
 194         memcpy(&wwn->vendor[0], &buf[8], sizeof(wwn->vendor));
 195         memcpy(&wwn->model[0], &buf[16], sizeof(wwn->model));
 196         memcpy(&wwn->revision[0], &buf[32], sizeof(wwn->revision));
 197 }
 198
 199 static int
 200 pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
 201 {
 202         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 203         int ret;
 204
 205         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 206         if (!buf)
 207                 return -ENOMEM;
 208
 209         memset(cdb, 0, MAX_COMMAND_SIZE);
 210         cdb[0] = INQUIRY;
 211         cdb[1] = 0x01; /* Query VPD */
 212         cdb[2] = 0x80; /* Unit Serial Number */
 213         cdb[3] = (INQUIRY_VPD_SERIAL_LEN >> 8) & 0xff;
 214         cdb[4] = (INQUIRY_VPD_SERIAL_LEN & 0xff);
 215
 216         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 217                               INQUIRY_VPD_SERIAL_LEN, NULL, HZ, 1, NULL);
 218         if (ret)
 219                 goto out_free;
 220
 221         snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
 222
 223         wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
 224
 225         kfree(buf);
 226         return 0;
 227
 228 out_free:
 229         kfree(buf);
 230         return -EPERM;
 231 }
 232
 233 static void
 234 pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
 235                 struct t10_wwn *wwn)
 236 {
 237         unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
 238         int ident_len, page_len, off = 4, ret;
 239         struct t10_vpd *vpd;
 240
 241         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 242         if (!buf)
 243                 return;
 244
 245         memset(cdb, 0, MAX_COMMAND_SIZE);
 246         cdb[0] = INQUIRY;
 247         cdb[1] = 0x01; /* Query VPD */
 248         cdb[2] = 0x83; /* Device Identifier */
 249         cdb[3] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN >> 8) & 0xff;
 250         cdb[4] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN & 0xff);
 251
 252         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 253                               INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
 254                               NULL, HZ, 1, NULL);
 255         if (ret)
 256                 goto out;
 257
 258         page_len = (buf[2] << 8) | buf[3];
 259         while (page_len > 0) {
 260                 /* Grab a pointer to the Identification descriptor */
 261                 page_83 = &buf[off];
 262                 ident_len = page_83[3];
 263                 if (!ident_len) {
 264                         pr_err("page_83[3]: identifier"
 265                                         " length zero!\n");
 266                         break;
 267                 }
 268                 pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
 269
 270                 vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
 271                 if (!vpd) {
 272                         pr_err("Unable to allocate memory for"
 273                                         " struct t10_vpd\n");
 274                         goto out;
 275                 }
 276                 INIT_LIST_HEAD(&vpd->vpd_list);
 277
 278                 transport_set_vpd_proto_id(vpd, page_83);
 279                 transport_set_vpd_assoc(vpd, page_83);
 280
 281                 if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
 282                         off += (ident_len + 4);
 283                         page_len -= (ident_len + 4);
 284                         kfree(vpd);
 285                         continue;
 286                 }
 287                 if (transport_set_vpd_ident(vpd, page_83) < 0) {
 288                         off += (ident_len + 4);
 289                         page_len -= (ident_len + 4);
 290                         kfree(vpd);
 291                         continue;
 292                 }
 293
 294                 list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
 295                 off += (ident_len + 4);
 296                 page_len -= (ident_len + 4);
 297         }
 298
 299 out:
 300         kfree(buf);
 301 }
 302
 303 static int pscsi_add_device_to_list(struct se_device *dev,
 304                 struct scsi_device *sd)
 305 {
 306         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 307         struct request_queue *q = sd->request_queue;
 308
 309         pdv->pdv_sd = sd;
 310
 311         if (!sd->queue_depth) {
 312                 sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
 313
 314                 pr_err("Set broken SCSI Device %d:%d:%llu"
 315                         " queue_depth to %d\n", sd->channel, sd->id,
 316                                 sd->lun, sd->queue_depth);
 317         }
 318
 319         dev->dev_attrib.hw_block_size = sd->sector_size;
 320         dev->dev_attrib.hw_max_sectors =
 321                 min_t(int, sd->host->max_sectors, queue_max_hw_sectors(q));
 322         dev->dev_attrib.hw_queue_depth = sd->queue_depth;
 323
 324         /*
 325          * Setup our standard INQUIRY info into se_dev->t10_wwn
 326          */
 327         pscsi_set_inquiry_info(sd, &dev->t10_wwn);
 328
 329         /*
 330          * Locate VPD WWN Information used for various purposes within
 331          * the Storage Engine.
 332          */
 333         if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
 334                 /*
 335                  * If VPD Unit Serial returned GOOD status, try
 336                  * VPD Device Identification page (0x83).
 337                  */
 338                 pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
 339         }
 340
 341         /*
 342          * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
 343          */
 344         if (sd->type == TYPE_TAPE)
 345                 pscsi_tape_read_blocksize(dev, sd);
 346         return 0;
 347 }
 348
 349 static struct se_device *pscsi_alloc_device(struct se_hba *hba,
 350                 const char *name)
 351 {
 352         struct pscsi_dev_virt *pdv;
 353
 354         pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
 355         if (!pdv) {
 356                 pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
 357                 return NULL;
 358         }
 359
 360         pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
 361         return &pdv->dev;
 362 }
 363
 364 /*
 365  * Called with struct Scsi_Host->host_lock called.
 366  */
 367 static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
 368         __releases(sh->host_lock)
 369 {
 370         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 371         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 372         struct Scsi_Host *sh = sd->host;
 373         struct block_device *bd;
 374         int ret;
 375
 376         if (scsi_device_get(sd)) {
 377                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 378                         sh->host_no, sd->channel, sd->id, sd->lun);
 379                 spin_unlock_irq(sh->host_lock);
 380                 return -EIO;
 381         }
 382         spin_unlock_irq(sh->host_lock);
 383         /*
 384          * Claim exclusive struct block_device access to struct scsi_device
 385          * for TYPE_DISK using supplied udev_path
 386          */
 387         bd = blkdev_get_by_path(dev->udev_path,
 388                                 FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
 389         if (IS_ERR(bd)) {
 390                 pr_err("pSCSI: blkdev_get_by_path() failed\n");
 391                 scsi_device_put(sd);
 392                 return PTR_ERR(bd);
 393         }
 394         pdv->pdv_bd = bd;
 395
 396         ret = pscsi_add_device_to_list(dev, sd);
 397         if (ret) {
 398                 blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 399                 scsi_device_put(sd);
 400                 return ret;
 401         }
 402
 403         pr_debug("CORE_PSCSI[%d] - Added TYPE_DISK for %d:%d:%d:%llu\n",
 404                 phv->phv_host_id, sh->host_no, sd->channel, sd->id, sd->lun);
 405         return 0;
 406 }
 407
 408 /*
 409  * Called with struct Scsi_Host->host_lock called.
 410  */
 411 static int pscsi_create_type_rom(struct se_device *dev, struct scsi_device *sd)
 412         __releases(sh->host_lock)
 413 {
 414         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 415         struct Scsi_Host *sh = sd->host;
 416         int ret;
 417
 418         if (scsi_device_get(sd)) {
 419                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 420                         sh->host_no, sd->channel, sd->id, sd->lun);
 421                 spin_unlock_irq(sh->host_lock);
 422                 return -EIO;
 423         }
 424         spin_unlock_irq(sh->host_lock);
 425
 426         ret = pscsi_add_device_to_list(dev, sd);
 427         if (ret) {
 428                 scsi_device_put(sd);
 429                 return ret;
 430         }
 431         pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
 432                 phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
 433                 sd->channel, sd->id, sd->lun);
 434
 435         return 0;
 436 }
 437
 438 /*
 439  * Called with struct Scsi_Host->host_lock called.
 440  */
 441 static int pscsi_create_type_other(struct se_device *dev,
 442                 struct scsi_device *sd)
 443         __releases(sh->host_lock)
 444 {
 445         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 446         struct Scsi_Host *sh = sd->host;
 447         int ret;
 448
 449         spin_unlock_irq(sh->host_lock);
 450         ret = pscsi_add_device_to_list(dev, sd);
 451         if (ret)
 452                 return ret;
 453
 454         pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
 455                 phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
 456                 sd->channel, sd->id, sd->lun);
 457         return 0;
 458 }
 459
 460 static int pscsi_configure_device(struct se_device *dev)
 461 {
 462         struct se_hba *hba = dev->se_hba;
 463         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 464         struct scsi_device *sd;
 465         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 466         struct Scsi_Host *sh = phv->phv_lld_host;
 467         int legacy_mode_enable = 0;
 468         int ret;
 469
 470         if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
 471             !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
 472             !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
 473                 pr_err("Missing scsi_channel_id=, scsi_target_id= and"
 474                         " scsi_lun_id= parameters\n");
 475                 return -EINVAL;
 476         }
 477
 478         /*
 479          * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
 480          * struct Scsi_Host we will need to bring the TCM/pSCSI object online
 481          */
 482         if (!sh) {
 483                 if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 484                         pr_err("pSCSI: Unable to locate struct"
 485                                 " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
 486                         return -ENODEV;
 487                 }
 488                 /*
 489                  * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
 490                  * reference, we enforce that udev_path has been set
 491                  */
 492                 if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
 493                         pr_err("pSCSI: udev_path attribute has not"
 494                                 " been set before ENABLE=1\n");
 495                         return -EINVAL;
 496                 }
 497                 /*
 498                  * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
 499                  * use the original TCM hba ID to reference Linux/SCSI Host No
 500                  * and enable for PHV_LLD_SCSI_HOST_NO mode.
 501                  */
 502                 if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
 503                         if (hba->dev_count) {
 504                                 pr_err("pSCSI: Unable to set hba_mode"
 505                                         " with active devices\n");
 506                                 return -EEXIST;
 507                         }
 508
 509                         if (pscsi_pmode_enable_hba(hba, 1) != 1)
 510                                 return -ENODEV;
 511
 512                         legacy_mode_enable = 1;
 513                         hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
 514                         sh = phv->phv_lld_host;
 515                 } else {
 516                         sh = scsi_host_lookup(pdv->pdv_host_id);
 517                         if (!sh) {
 518                                 pr_err("pSCSI: Unable to locate"
 519                                         " pdv_host_id: %d\n", pdv->pdv_host_id);
 520                                 return -EINVAL;
 521                         }
 522                         pdv->pdv_lld_host = sh;
 523                 }
 524         } else {
 525                 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
 526                         pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
 527                                 " struct Scsi_Host exists\n");
 528                         return -EEXIST;
 529                 }
 530         }
 531
 532         spin_lock_irq(sh->host_lock);
 533         list_for_each_entry(sd, &sh->__devices, siblings) {
 534                 if ((pdv->pdv_channel_id != sd->channel) ||
 535                     (pdv->pdv_target_id != sd->id) ||
 536                     (pdv->pdv_lun_id != sd->lun))
 537                         continue;
 538                 /*
 539                  * Functions will release the held struct scsi_host->host_lock
 540                  * before calling calling pscsi_add_device_to_list() to register
 541                  * struct scsi_device with target_core_mod.
 542                  */
 543                 switch (sd->type) {
 544                 case TYPE_DISK:
 545                         ret = pscsi_create_type_disk(dev, sd);
 546                         break;
 547                 case TYPE_ROM:
 548                         ret = pscsi_create_type_rom(dev, sd);
 549                         break;
 550                 default:
 551                         ret = pscsi_create_type_other(dev, sd);
 552                         break;
 553                 }
 554
 555                 if (ret) {
 556                         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 557                                 scsi_host_put(sh);
 558                         else if (legacy_mode_enable) {
 559                                 pscsi_pmode_enable_hba(hba, 0);
 560                                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 561                         }
 562                         pdv->pdv_sd = NULL;
 563                         return ret;
 564                 }
 565                 return 0;
 566         }
 567         spin_unlock_irq(sh->host_lock);
 568
 569         pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
 570                 pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
 571
 572         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 573                 scsi_host_put(sh);
 574         else if (legacy_mode_enable) {
 575                 pscsi_pmode_enable_hba(hba, 0);
 576                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 577         }
 578
 579         return -ENODEV;
 580 }
 581
 582 static void pscsi_free_device(struct se_device *dev)
 583 {
 584         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 585         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 586         struct scsi_device *sd = pdv->pdv_sd;
 587
 588         if (sd) {
 589                 /*
 590                  * Release exclusive pSCSI internal struct block_device claim for
 591                  * struct scsi_device with TYPE_DISK from pscsi_create_type_disk()
 592                  */
 593                 if ((sd->type == TYPE_DISK) && pdv->pdv_bd) {
 594                         blkdev_put(pdv->pdv_bd,
 595                                    FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 596                         pdv->pdv_bd = NULL;
 597                 }
 598                 /*
 599                  * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
 600                  * to struct Scsi_Host now.
 601                  */
 602                 if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
 603                     (phv->phv_lld_host != NULL))
 604                         scsi_host_put(phv->phv_lld_host);
 605                 else if (pdv->pdv_lld_host)
 606                         scsi_host_put(pdv->pdv_lld_host);
 607
 608                 if ((sd->type == TYPE_DISK) || (sd->type == TYPE_ROM))
 609                         scsi_device_put(sd);
 610
 611                 pdv->pdv_sd = NULL;
 612         }
 613
 614         kfree(pdv);
 615 }
 616
 617 static void pscsi_transport_complete(struct se_cmd *cmd, struct scatterlist *sg,
 618                                      unsigned char *sense_buffer)
 619 {
 620         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 621         struct scsi_device *sd = pdv->pdv_sd;
 622         int result;
 623         struct pscsi_plugin_task *pt = cmd->priv;
 624         unsigned char *cdb;
 625         /*
 626          * Special case for REPORT_LUNs handling where pscsi_plugin_task has
 627          * not been allocated because TCM is handling the emulation directly.
 628          */
 629         if (!pt)
 630                 return;
 631
 632         cdb = &pt->pscsi_cdb[0];
 633         result = pt->pscsi_result;
 634         /*
 635          * Hack to make sure that Write-Protect modepage is set if R/O mode is
 636          * forced.
 637          */
 638         if (!cmd->se_deve || !cmd->data_length)
 639                 goto after_mode_sense;
 640
 641         if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
 642              (status_byte(result) << 1) == SAM_STAT_GOOD) {
 643                 if (cmd->se_deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY) {
 644                         unsigned char *buf;
 645
 646                         buf = transport_kmap_data_sg(cmd);
 647                         if (!buf)
 648                                 ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
 649
 650                         if (cdb[0] == MODE_SENSE_10) {
 651                                 if (!(buf[3] & 0x80))
 652                                         buf[3] |= 0x80;
 653                         } else {
 654                                 if (!(buf[2] & 0x80))
 655                                         buf[2] |= 0x80;
 656                         }
 657
 658                         transport_kunmap_data_sg(cmd);
 659                 }
 660         }
 661 after_mode_sense:
 662
 663         if (sd->type != TYPE_TAPE || !cmd->data_length)
 664                 goto after_mode_select;
 665
 666         /*
 667          * Hack to correctly obtain the initiator requested blocksize for
 668          * TYPE_TAPE.  Since this value is dependent upon each tape media,
 669          * struct scsi_device->sector_size will not contain the correct value
 670          * by default, so we go ahead and set it so
 671          * TRANSPORT(dev)->get_blockdev() returns the correct value to the
 672          * storage engine.
 673          */
 674         if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
 675               (status_byte(result) << 1) == SAM_STAT_GOOD) {
 676                 unsigned char *buf;
 677                 u16 bdl;
 678                 u32 blocksize;
 679
 680                 buf = sg_virt(&sg[0]);
 681                 if (!buf) {
 682                         pr_err("Unable to get buf for scatterlist\n");
 683                         goto after_mode_select;
 684                 }
 685
 686                 if (cdb[0] == MODE_SELECT)
 687                         bdl = (buf[3]);
 688                 else
 689                         bdl = (buf[6] << 8) | (buf[7]);
 690
 691                 if (!bdl)
 692                         goto after_mode_select;
 693
 694                 if (cdb[0] == MODE_SELECT)
 695                         blocksize = (buf[9] << 16) | (buf[10] << 8) |
 696                                         (buf[11]);
 697                 else
 698                         blocksize = (buf[13] << 16) | (buf[14] << 8) |
 699                                         (buf[15]);
 700
 701                 sd->sector_size = blocksize;
 702         }
 703 after_mode_select:
 704
 705         if (sense_buffer && (status_byte(result) & CHECK_CONDITION)) {
 706                 memcpy(sense_buffer, pt->pscsi_sense, TRANSPORT_SENSE_BUFFER);
 707                 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
 708         }
 709 }
 710
 711 enum {
 712         Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
 713         Opt_scsi_lun_id, Opt_err
 714 };
 715
 716 static match_table_t tokens = {
 717         {Opt_scsi_host_id, "scsi_host_id=%d"},
 718         {Opt_scsi_channel_id, "scsi_channel_id=%d"},
 719         {Opt_scsi_target_id, "scsi_target_id=%d"},
 720         {Opt_scsi_lun_id, "scsi_lun_id=%d"},
 721         {Opt_err, NULL}
 722 };
 723
 724 static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
 725                 const char *page, ssize_t count)
 726 {
 727         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 728         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 729         char *orig, *ptr, *opts;
 730         substring_t args[MAX_OPT_ARGS];
 731         int ret = 0, arg, token;
 732
 733         opts = kstrdup(page, GFP_KERNEL);
 734         if (!opts)
 735                 return -ENOMEM;
 736
 737         orig = opts;
 738
 739         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 740                 if (!*ptr)
 741                         continue;
 742
 743                 token = match_token(ptr, tokens, args);
 744                 switch (token) {
 745                 case Opt_scsi_host_id:
 746                         if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 747                                 pr_err("PSCSI[%d]: Unable to accept"
 748                                         " scsi_host_id while phv_mode =="
 749                                         " PHV_LLD_SCSI_HOST_NO\n",
 750                                         phv->phv_host_id);
 751                                 ret = -EINVAL;
 752                                 goto out;
 753                         }
 754                         ret = match_int(args, &arg);
 755                         if (ret)
 756                                 goto out;
 757                         pdv->pdv_host_id = arg;
 758                         pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
 759                                 " %d\n", phv->phv_host_id, pdv->pdv_host_id);
 760                         pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
 761                         break;
 762                 case Opt_scsi_channel_id:
 763                         ret = match_int(args, &arg);
 764                         if (ret)
 765                                 goto out;
 766                         pdv->pdv_channel_id = arg;
 767                         pr_debug("PSCSI[%d]: Referencing SCSI Channel"
 768                                 " ID: %d\n",  phv->phv_host_id,
 769                                 pdv->pdv_channel_id);
 770                         pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
 771                         break;
 772                 case Opt_scsi_target_id:
 773                         ret = match_int(args, &arg);
 774                         if (ret)
 775                                 goto out;
 776                         pdv->pdv_target_id = arg;
 777                         pr_debug("PSCSI[%d]: Referencing SCSI Target"
 778                                 " ID: %d\n", phv->phv_host_id,
 779                                 pdv->pdv_target_id);
 780                         pdv->pdv_flags |= PDF_HAS_TARGET_ID;
 781                         break;
 782                 case Opt_scsi_lun_id:
 783                         ret = match_int(args, &arg);
 784                         if (ret)
 785                                 goto out;
 786                         pdv->pdv_lun_id = arg;
 787                         pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
 788                                 " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
 789                         pdv->pdv_flags |= PDF_HAS_LUN_ID;
 790                         break;
 791                 default:
 792                         break;
 793                 }
 794         }
 795
 796 out:
 797         kfree(orig);
 798         return (!ret) ? count : ret;
 799 }
 800
 801 static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
 802 {
 803         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 804         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 805         struct scsi_device *sd = pdv->pdv_sd;
 806         unsigned char host_id[16];
 807         ssize_t bl;
 808         int i;
 809
 810         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 811                 snprintf(host_id, 16, "%d", pdv->pdv_host_id);
 812         else
 813                 snprintf(host_id, 16, "PHBA Mode");
 814
 815         bl = sprintf(b, "SCSI Device Bus Location:"
 816                 " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
 817                 pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
 818                 host_id);
 819
 820         if (sd) {
 821                 bl += sprintf(b + bl, "        ");
 822                 bl += sprintf(b + bl, "Vendor: ");
 823                 for (i = 0; i < 8; i++) {
 824                         if (ISPRINT(sd->vendor[i]))   /* printable character? */
 825                                 bl += sprintf(b + bl, "%c", sd->vendor[i]);
 826                         else
 827                                 bl += sprintf(b + bl, " ");
 828                 }
 829                 bl += sprintf(b + bl, " Model: ");
 830                 for (i = 0; i < 16; i++) {
 831                         if (ISPRINT(sd->model[i]))   /* printable character ? */
 832                                 bl += sprintf(b + bl, "%c", sd->model[i]);
 833                         else
 834                                 bl += sprintf(b + bl, " ");
 835                 }
 836                 bl += sprintf(b + bl, " Rev: ");
 837                 for (i = 0; i < 4; i++) {
 838                         if (ISPRINT(sd->rev[i]))   /* printable character ? */
 839                                 bl += sprintf(b + bl, "%c", sd->rev[i]);
 840                         else
 841                                 bl += sprintf(b + bl, " ");
 842                 }
 843                 bl += sprintf(b + bl, "\n");
 844         }
 845         return bl;
 846 }
 847
 848 static void pscsi_bi_endio(struct bio *bio, int error)
 849 {
 850         bio_put(bio);
 851 }
 852
 853 static inline struct bio *pscsi_get_bio(int nr_vecs)
 854 {
 855         struct bio *bio;
 856         /*
 857          * Use bio_malloc() following the comment in for bio -> struct request
 858          * in block/blk-core.c:blk_make_request()
 859          */
 860         bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
 861         if (!bio) {
 862                 pr_err("PSCSI: bio_kmalloc() failed\n");
 863                 return NULL;
 864         }
 865         bio->bi_end_io = pscsi_bi_endio;
 866
 867         return bio;
 868 }
 869
 870 static sense_reason_t
 871 pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 872                 enum dma_data_direction data_direction, struct bio **hbio)
 873 {
 874         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 875         struct bio *bio = NULL, *tbio = NULL;
 876         struct page *page;
 877         struct scatterlist *sg;
 878         u32 data_len = cmd->data_length, i, len, bytes, off;
 879         int nr_pages = (cmd->data_length + sgl[0].offset +
 880                         PAGE_SIZE - 1) >> PAGE_SHIFT;
 881         int nr_vecs = 0, rc;
 882         int rw = (data_direction == DMA_TO_DEVICE);
 883
 884         *hbio = NULL;
 885
 886         pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
 887
 888         for_each_sg(sgl, sg, sgl_nents, i) {
 889                 page = sg_page(sg);
 890                 off = sg->offset;
 891                 len = sg->length;
 892
 893                 pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
 894                         page, len, off);
 895
 896                 /*
 897                  * We only have one page of data in each sg element,
 898                  * we can not cross a page boundary.
 899                  */
 900                 if (off + len > PAGE_SIZE)
 901                         goto fail;
 902
 903                 if (len > 0 && data_len > 0) {
 904                         bytes = min_t(unsigned int, len, PAGE_SIZE - off);
 905                         bytes = min(bytes, data_len);
 906
 907                         if (!bio) {
 908                                 nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
 909                                 nr_pages -= nr_vecs;
 910                                 /*
 911                                  * Calls bio_kmalloc() and sets bio->bi_end_io()
 912                                  */
 913                                 bio = pscsi_get_bio(nr_vecs);
 914                                 if (!bio)
 915                                         goto fail;
 916
 917                                 if (rw)
 918                                         bio->bi_rw |= REQ_WRITE;
 919
 920                                 pr_debug("PSCSI: Allocated bio: %p,"
 921                                         " dir: %s nr_vecs: %d\n", bio,
 922                                         (rw) ? "rw" : "r", nr_vecs);
 923                                 /*
 924                                  * Set *hbio pointer to handle the case:
 925                                  * nr_pages > BIO_MAX_PAGES, where additional
 926                                  * bios need to be added to complete a given
 927                                  * command.
 928                                  */
 929                                 if (!*hbio)
 930                                         *hbio = tbio = bio;
 931                                 else
 932                                         tbio = tbio->bi_next = bio;
 933                         }
 934
 935                         pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
 936                                 " bio: %p page: %p len: %d off: %d\n", i, bio,
 937                                 page, len, off);
 938
 939                         rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
 940                                         bio, page, bytes, off);
 941                         if (rc != bytes)
 942                                 goto fail;
 943
 944                         pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
 945                                 bio->bi_vcnt, nr_vecs);
 946
 947                         if (bio->bi_vcnt > nr_vecs) {
 948                                 pr_debug("PSCSI: Reached bio->bi_vcnt max:"
 949                                         " %d i: %d bio: %p, allocating another"
 950                                         " bio\n", bio->bi_vcnt, i, bio);
 951                                 /*
 952                                  * Clear the pointer so that another bio will
 953                                  * be allocated with pscsi_get_bio() above, the
 954                                  * current bio has already been set *tbio and
 955                                  * bio->bi_next.
 956                                  */
 957                                 bio = NULL;
 958                         }
 959
 960                         data_len -= bytes;
 961                 }
 962         }
 963
 964         return 0;
 965 fail:
 966         while (*hbio) {
 967                 bio = *hbio;
 968                 *hbio = (*hbio)->bi_next;
 969                 bio_endio(bio, 0);      /* XXX: should be error */
 970         }
 971         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 972 }
 973
 974 static sense_reason_t
 975 pscsi_parse_cdb(struct se_cmd *cmd)
 976 {
 977         if (cmd->se_cmd_flags & SCF_BIDI)
 978                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 979
 980         return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
 981 }
 982
 983 static sense_reason_t
 984 pscsi_execute_cmd(struct se_cmd *cmd)
 985 {
 986         struct scatterlist *sgl = cmd->t_data_sg;
 987         u32 sgl_nents = cmd->t_data_nents;
 988         enum dma_data_direction data_direction = cmd->data_direction;
 989         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 990         struct pscsi_plugin_task *pt;
 991         struct request *req;
 992         struct bio *hbio;
 993         sense_reason_t ret;
 994
 995         /*
 996          * Dynamically alloc cdb space, since it may be larger than
 997          * TCM_MAX_COMMAND_SIZE
 998          */
 999         pt = kzalloc(sizeof(*pt) + scsi_command_size(cmd->t_task_cdb), GFP_KERNEL);
1000         if (!pt) {
1001                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1002         }
1003         cmd->priv = pt;
1004
1005         memcpy(pt->pscsi_cdb, cmd->t_task_cdb,
1006                 scsi_command_size(cmd->t_task_cdb));
1007
1008         if (!sgl) {
1009                 req = blk_get_request(pdv->pdv_sd->request_queue,
1010                                 (data_direction == DMA_TO_DEVICE),
1011                                 GFP_KERNEL);
1012                 if (IS_ERR(req)) {
1013                         pr_err("PSCSI: blk_get_request() failed\n");
1014                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1015                         goto fail;
1016                 }
1017
1018                 blk_rq_set_block_pc(req);
1019         } else {
1020                 BUG_ON(!cmd->data_length);
1021
1022                 ret = pscsi_map_sg(cmd, sgl, sgl_nents, data_direction, &hbio);
1023                 if (ret)
1024                         goto fail;
1025
1026                 req = blk_make_request(pdv->pdv_sd->request_queue, hbio,
1027                                        GFP_KERNEL);
1028                 if (IS_ERR(req)) {
1029                         pr_err("pSCSI: blk_make_request() failed\n");
1030                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1031                         goto fail_free_bio;
1032                 }
1033         }
1034
1035         req->end_io = pscsi_req_done;
1036         req->end_io_data = cmd;
1037         req->cmd_len = scsi_command_size(pt->pscsi_cdb);
1038         req->cmd = &pt->pscsi_cdb[0];
1039         req->sense = &pt->pscsi_sense[0];
1040         req->sense_len = 0;
1041         if (pdv->pdv_sd->type == TYPE_DISK)
1042                 req->timeout = PS_TIMEOUT_DISK;
1043         else
1044                 req->timeout = PS_TIMEOUT_OTHER;
1045         req->retries = PS_RETRY;
1046
1047         blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL, req,
1048                         (cmd->sam_task_attr == TCM_HEAD_TAG),
1049                         pscsi_req_done);
1050
1051         return 0;
1052
1053 fail_free_bio:
1054         while (hbio) {
1055                 struct bio *bio = hbio;
1056                 hbio = hbio->bi_next;
1057                 bio_endio(bio, 0);      /* XXX: should be error */
1058         }
1059         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1060 fail:
1061         kfree(pt);
1062         return ret;
1063 }
1064
1065 /*      pscsi_get_device_type():
1066  *
1067  *
1068  */
1069 static u32 pscsi_get_device_type(struct se_device *dev)
1070 {
1071         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1072         struct scsi_device *sd = pdv->pdv_sd;
1073
1074         return (sd) ? sd->type : TYPE_NO_LUN;
1075 }
1076
1077 static sector_t pscsi_get_blocks(struct se_device *dev)
1078 {
1079         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1080
1081         if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
1082                 return pdv->pdv_bd->bd_part->nr_sects;
1083
1084         dump_stack();
1085         return 0;
1086 }
1087
1088 static void pscsi_req_done(struct request *req, int uptodate)
1089 {
1090         struct se_cmd *cmd = req->end_io_data;
1091         struct pscsi_plugin_task *pt = cmd->priv;
1092
1093         pt->pscsi_result = req->errors;
1094         pt->pscsi_resid = req->resid_len;
1095
1096         cmd->scsi_status = status_byte(pt->pscsi_result) << 1;
1097         if (cmd->scsi_status) {
1098                 pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1099                         " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1100                         pt->pscsi_result);
1101         }
1102
1103         switch (host_byte(pt->pscsi_result)) {
1104         case DID_OK:
1105                 target_complete_cmd(cmd, cmd->scsi_status);
1106                 break;
1107         default:
1108                 pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1109                         " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1110                         pt->pscsi_result);
1111                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1112                 break;
1113         }
1114
1115         __blk_put_request(req->q, req);
1116         kfree(pt);
1117 }
1118
1119 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_pi_prot_type);
1120 TB_DEV_ATTR_RO(pscsi, hw_pi_prot_type);
1121
1122 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_block_size);
1123 TB_DEV_ATTR_RO(pscsi, hw_block_size);
1124
1125 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_max_sectors);
1126 TB_DEV_ATTR_RO(pscsi, hw_max_sectors);
1127
1128 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_queue_depth);
1129 TB_DEV_ATTR_RO(pscsi, hw_queue_depth);
1130
1131 static struct configfs_attribute *pscsi_backend_dev_attrs[] = {
1132         &pscsi_dev_attrib_hw_pi_prot_type.attr,
1133         &pscsi_dev_attrib_hw_block_size.attr,
1134         &pscsi_dev_attrib_hw_max_sectors.attr,
1135         &pscsi_dev_attrib_hw_queue_depth.attr,
1136         NULL,
1137 };
1138
1139 static struct se_subsystem_api pscsi_template = {
1140         .name                   = "pscsi",
1141         .owner                  = THIS_MODULE,
1142         .transport_flags        = TRANSPORT_FLAG_PASSTHROUGH,
1143         .attach_hba             = pscsi_attach_hba,
1144         .detach_hba             = pscsi_detach_hba,
1145         .pmode_enable_hba       = pscsi_pmode_enable_hba,
1146         .alloc_device           = pscsi_alloc_device,
1147         .configure_device       = pscsi_configure_device,
1148         .free_device            = pscsi_free_device,
1149         .transport_complete     = pscsi_transport_complete,
1150         .parse_cdb              = pscsi_parse_cdb,
1151         .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1152         .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1153         .get_device_type        = pscsi_get_device_type,
1154         .get_blocks             = pscsi_get_blocks,
1155 };
1156
1157 static int __init pscsi_module_init(void)
1158 {
1159         struct target_backend_cits *tbc = &pscsi_template.tb_cits;
1160
1161         target_core_setup_sub_cits(&pscsi_template);
1162         tbc->tb_dev_attrib_cit.ct_attrs = pscsi_backend_dev_attrs;
1163
1164         return transport_subsystem_register(&pscsi_template);
1165 }
1166
1167 static void __exit pscsi_module_exit(void)
1168 {
1169         transport_subsystem_release(&pscsi_template);
1170 }
1171
1172 MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1173 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1174 MODULE_LICENSE("GPL");
1175
1176 module_init(pscsi_module_init);
1177 module_exit(pscsi_module_exit);