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