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