linux/drivers/target/target_core_pscsi.c
<<
>>
Prefs
   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
  52static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
  53{
  54        return container_of(dev, struct pscsi_dev_virt, dev);
  55}
  56
  57static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
  58static 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 */
  65static 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
  88static 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
 108static 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
 149static 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;
 174out_free:
 175        kfree(buf);
 176}
 177
 178static void
 179pscsi_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
 197static int
 198pscsi_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
 226out_free:
 227        kfree(buf);
 228        return -EPERM;
 229}
 230
 231static void
 232pscsi_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
 297out:
 298        kfree(buf);
 299}
 300
 301static 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
 347static 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 */
 365static 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 */
 409static 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 */
 439static 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
 458static 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
 580static 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
 588static 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
 622static 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        }
 668after_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        }
 710after_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
 718enum {
 719        Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
 720        Opt_scsi_lun_id, Opt_err
 721};
 722
 723static 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
 731static 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
 803out:
 804        kfree(orig);
 805        return (!ret) ? count : ret;
 806}
 807
 808static 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
 855static void pscsi_bi_endio(struct bio *bio)
 856{
 857        bio_put(bio);
 858}
 859
 860static 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
 877static sense_reason_t
 878pscsi_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;
 972fail:
 973        while (*hbio) {
 974                bio = *hbio;
 975                *hbio = (*hbio)->bi_next;
 976                bio_endio(bio);
 977        }
 978        return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 979}
 980
 981static sense_reason_t
 982pscsi_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
 990static sense_reason_t
 991pscsi_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
1060fail_free_bio:
1061        while (hbio) {
1062                struct bio *bio = hbio;
1063                hbio = hbio->bi_next;
1064                bio_endio(bio);
1065        }
1066        ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1067fail:
1068        kfree(pt);
1069        return ret;
1070}
1071
1072/*      pscsi_get_device_type():
1073 *
1074 *
1075 */
1076static 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
1084static 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
1095static 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
1126static 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
1145static int __init pscsi_module_init(void)
1146{
1147        return transport_backend_register(&pscsi_ops);
1148}
1149
1150static void __exit pscsi_module_exit(void)
1151{
1152        target_backend_unregister(&pscsi_ops);
1153}
1154
1155MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1156MODULE_AUTHOR("nab@Linux-iSCSI.org");
1157MODULE_LICENSE("GPL");
1158
1159module_init(pscsi_module_init);
1160module_exit(pscsi_module_exit);
1161