linux/drivers/target/target_core_pscsi.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*******************************************************************************
   3 * Filename:  target_core_pscsi.c
   4 *
   5 * This file contains the generic target mode <-> Linux SCSI subsystem plugin.
   6 *
   7 * (c) Copyright 2003-2013 Datera, Inc.
   8 *
   9 * Nicholas A. Bellinger <nab@kernel.org>
  10 *
  11 ******************************************************************************/
  12
  13#include <linux/string.h>
  14#include <linux/parser.h>
  15#include <linux/timer.h>
  16#include <linux/blkdev.h>
  17#include <linux/blk_types.h>
  18#include <linux/slab.h>
  19#include <linux/spinlock.h>
  20#include <linux/genhd.h>
  21#include <linux/cdrom.h>
  22#include <linux/ratelimit.h>
  23#include <linux/module.h>
  24#include <asm/unaligned.h>
  25
  26#include <scsi/scsi_device.h>
  27#include <scsi/scsi_host.h>
  28#include <scsi/scsi_tcq.h>
  29
  30#include <target/target_core_base.h>
  31#include <target/target_core_backend.h>
  32
  33#include "target_core_alua.h"
  34#include "target_core_internal.h"
  35#include "target_core_pscsi.h"
  36
  37static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
  38{
  39        return container_of(dev, struct pscsi_dev_virt, dev);
  40}
  41
  42static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
  43static void pscsi_req_done(struct request *, blk_status_t);
  44
  45/*      pscsi_attach_hba():
  46 *
  47 *      pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
  48 *      from the passed SCSI Host ID.
  49 */
  50static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
  51{
  52        struct pscsi_hba_virt *phv;
  53
  54        phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
  55        if (!phv) {
  56                pr_err("Unable to allocate struct pscsi_hba_virt\n");
  57                return -ENOMEM;
  58        }
  59        phv->phv_host_id = host_id;
  60        phv->phv_mode = PHV_VIRTUAL_HOST_ID;
  61
  62        hba->hba_ptr = phv;
  63
  64        pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
  65                " Generic Target Core Stack %s\n", hba->hba_id,
  66                PSCSI_VERSION, TARGET_CORE_VERSION);
  67        pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
  68               hba->hba_id);
  69
  70        return 0;
  71}
  72
  73static void pscsi_detach_hba(struct se_hba *hba)
  74{
  75        struct pscsi_hba_virt *phv = hba->hba_ptr;
  76        struct Scsi_Host *scsi_host = phv->phv_lld_host;
  77
  78        if (scsi_host) {
  79                scsi_host_put(scsi_host);
  80
  81                pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
  82                        " Generic Target Core\n", hba->hba_id,
  83                        (scsi_host->hostt->name) ? (scsi_host->hostt->name) :
  84                        "Unknown");
  85        } else
  86                pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
  87                        " from Generic Target Core\n", hba->hba_id);
  88
  89        kfree(phv);
  90        hba->hba_ptr = NULL;
  91}
  92
  93static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
  94{
  95        struct pscsi_hba_virt *phv = hba->hba_ptr;
  96        struct Scsi_Host *sh = phv->phv_lld_host;
  97        /*
  98         * Release the struct Scsi_Host
  99         */
 100        if (!mode_flag) {
 101                if (!sh)
 102                        return 0;
 103
 104                phv->phv_lld_host = NULL;
 105                phv->phv_mode = PHV_VIRTUAL_HOST_ID;
 106
 107                pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
 108                        " %s\n", hba->hba_id, (sh->hostt->name) ?
 109                        (sh->hostt->name) : "Unknown");
 110
 111                scsi_host_put(sh);
 112                return 0;
 113        }
 114        /*
 115         * Otherwise, locate struct Scsi_Host from the original passed
 116         * pSCSI Host ID and enable for phba mode
 117         */
 118        sh = scsi_host_lookup(phv->phv_host_id);
 119        if (!sh) {
 120                pr_err("pSCSI: Unable to locate SCSI Host for"
 121                        " phv_host_id: %d\n", phv->phv_host_id);
 122                return -EINVAL;
 123        }
 124
 125        phv->phv_lld_host = sh;
 126        phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
 127
 128        pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
 129                hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
 130
 131        return 1;
 132}
 133
 134static void pscsi_tape_read_blocksize(struct se_device *dev,
 135                struct scsi_device *sdev)
 136{
 137        unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 138        int ret;
 139
 140        buf = kzalloc(12, GFP_KERNEL);
 141        if (!buf)
 142                goto out_free;
 143
 144        memset(cdb, 0, MAX_COMMAND_SIZE);
 145        cdb[0] = MODE_SENSE;
 146        cdb[4] = 0x0c; /* 12 bytes */
 147
 148        ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
 149                        HZ, 1, NULL);
 150        if (ret)
 151                goto out_free;
 152
 153        /*
 154         * If MODE_SENSE still returns zero, set the default value to 1024.
 155         */
 156        sdev->sector_size = get_unaligned_be24(&buf[9]);
 157out_free:
 158        if (!sdev->sector_size)
 159                sdev->sector_size = 1024;
 160
 161        kfree(buf);
 162}
 163
 164static void
 165pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
 166{
 167        if (sdev->inquiry_len < INQUIRY_LEN)
 168                return;
 169        /*
 170         * Use sdev->inquiry data from drivers/scsi/scsi_scan.c:scsi_add_lun()
 171         */
 172        BUILD_BUG_ON(sizeof(wwn->vendor) != INQUIRY_VENDOR_LEN + 1);
 173        snprintf(wwn->vendor, sizeof(wwn->vendor),
 174                 "%." __stringify(INQUIRY_VENDOR_LEN) "s", sdev->vendor);
 175        BUILD_BUG_ON(sizeof(wwn->model) != INQUIRY_MODEL_LEN + 1);
 176        snprintf(wwn->model, sizeof(wwn->model),
 177                 "%." __stringify(INQUIRY_MODEL_LEN) "s", sdev->model);
 178        BUILD_BUG_ON(sizeof(wwn->revision) != INQUIRY_REVISION_LEN + 1);
 179        snprintf(wwn->revision, sizeof(wwn->revision),
 180                 "%." __stringify(INQUIRY_REVISION_LEN) "s", sdev->rev);
 181}
 182
 183static int
 184pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
 185{
 186        unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 187        int ret;
 188
 189        buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 190        if (!buf)
 191                return -ENOMEM;
 192
 193        memset(cdb, 0, MAX_COMMAND_SIZE);
 194        cdb[0] = INQUIRY;
 195        cdb[1] = 0x01; /* Query VPD */
 196        cdb[2] = 0x80; /* Unit Serial Number */
 197        put_unaligned_be16(INQUIRY_VPD_SERIAL_LEN, &cdb[3]);
 198
 199        ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 200                              INQUIRY_VPD_SERIAL_LEN, NULL, HZ, 1, NULL);
 201        if (ret)
 202                goto out_free;
 203
 204        snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
 205
 206        wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
 207
 208        kfree(buf);
 209        return 0;
 210
 211out_free:
 212        kfree(buf);
 213        return -EPERM;
 214}
 215
 216static void
 217pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
 218                struct t10_wwn *wwn)
 219{
 220        unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
 221        int ident_len, page_len, off = 4, ret;
 222        struct t10_vpd *vpd;
 223
 224        buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 225        if (!buf)
 226                return;
 227
 228        memset(cdb, 0, MAX_COMMAND_SIZE);
 229        cdb[0] = INQUIRY;
 230        cdb[1] = 0x01; /* Query VPD */
 231        cdb[2] = 0x83; /* Device Identifier */
 232        put_unaligned_be16(INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, &cdb[3]);
 233
 234        ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 235                              INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
 236                              NULL, HZ, 1, NULL);
 237        if (ret)
 238                goto out;
 239
 240        page_len = get_unaligned_be16(&buf[2]);
 241        while (page_len > 0) {
 242                /* Grab a pointer to the Identification descriptor */
 243                page_83 = &buf[off];
 244                ident_len = page_83[3];
 245                if (!ident_len) {
 246                        pr_err("page_83[3]: identifier"
 247                                        " length zero!\n");
 248                        break;
 249                }
 250                pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
 251
 252                vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
 253                if (!vpd) {
 254                        pr_err("Unable to allocate memory for"
 255                                        " struct t10_vpd\n");
 256                        goto out;
 257                }
 258                INIT_LIST_HEAD(&vpd->vpd_list);
 259
 260                transport_set_vpd_proto_id(vpd, page_83);
 261                transport_set_vpd_assoc(vpd, page_83);
 262
 263                if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
 264                        off += (ident_len + 4);
 265                        page_len -= (ident_len + 4);
 266                        kfree(vpd);
 267                        continue;
 268                }
 269                if (transport_set_vpd_ident(vpd, page_83) < 0) {
 270                        off += (ident_len + 4);
 271                        page_len -= (ident_len + 4);
 272                        kfree(vpd);
 273                        continue;
 274                }
 275
 276                list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
 277                off += (ident_len + 4);
 278                page_len -= (ident_len + 4);
 279        }
 280
 281out:
 282        kfree(buf);
 283}
 284
 285static int pscsi_add_device_to_list(struct se_device *dev,
 286                struct scsi_device *sd)
 287{
 288        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 289        struct request_queue *q = sd->request_queue;
 290
 291        pdv->pdv_sd = sd;
 292
 293        if (!sd->queue_depth) {
 294                sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
 295
 296                pr_err("Set broken SCSI Device %d:%d:%llu"
 297                        " queue_depth to %d\n", sd->channel, sd->id,
 298                                sd->lun, sd->queue_depth);
 299        }
 300
 301        dev->dev_attrib.hw_block_size =
 302                min_not_zero((int)sd->sector_size, 512);
 303        dev->dev_attrib.hw_max_sectors =
 304                min_not_zero(sd->host->max_sectors, queue_max_hw_sectors(q));
 305        dev->dev_attrib.hw_queue_depth = sd->queue_depth;
 306
 307        /*
 308         * Setup our standard INQUIRY info into se_dev->t10_wwn
 309         */
 310        pscsi_set_inquiry_info(sd, &dev->t10_wwn);
 311
 312        /*
 313         * Locate VPD WWN Information used for various purposes within
 314         * the Storage Engine.
 315         */
 316        if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
 317                /*
 318                 * If VPD Unit Serial returned GOOD status, try
 319                 * VPD Device Identification page (0x83).
 320                 */
 321                pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
 322        }
 323
 324        /*
 325         * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
 326         */
 327        if (sd->type == TYPE_TAPE) {
 328                pscsi_tape_read_blocksize(dev, sd);
 329                dev->dev_attrib.hw_block_size = sd->sector_size;
 330        }
 331        return 0;
 332}
 333
 334static struct se_device *pscsi_alloc_device(struct se_hba *hba,
 335                const char *name)
 336{
 337        struct pscsi_dev_virt *pdv;
 338
 339        pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
 340        if (!pdv) {
 341                pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
 342                return NULL;
 343        }
 344
 345        pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
 346        return &pdv->dev;
 347}
 348
 349/*
 350 * Called with struct Scsi_Host->host_lock called.
 351 */
 352static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
 353        __releases(sh->host_lock)
 354{
 355        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 356        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 357        struct Scsi_Host *sh = sd->host;
 358        struct block_device *bd;
 359        int ret;
 360
 361        if (scsi_device_get(sd)) {
 362                pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 363                        sh->host_no, sd->channel, sd->id, sd->lun);
 364                spin_unlock_irq(sh->host_lock);
 365                return -EIO;
 366        }
 367        spin_unlock_irq(sh->host_lock);
 368        /*
 369         * Claim exclusive struct block_device access to struct scsi_device
 370         * for TYPE_DISK and TYPE_ZBC using supplied udev_path
 371         */
 372        bd = blkdev_get_by_path(dev->udev_path,
 373                                FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
 374        if (IS_ERR(bd)) {
 375                pr_err("pSCSI: blkdev_get_by_path() failed\n");
 376                scsi_device_put(sd);
 377                return PTR_ERR(bd);
 378        }
 379        pdv->pdv_bd = bd;
 380
 381        ret = pscsi_add_device_to_list(dev, sd);
 382        if (ret) {
 383                blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 384                scsi_device_put(sd);
 385                return ret;
 386        }
 387
 388        pr_debug("CORE_PSCSI[%d] - Added TYPE_%s for %d:%d:%d:%llu\n",
 389                phv->phv_host_id, sd->type == TYPE_DISK ? "DISK" : "ZBC",
 390                sh->host_no, sd->channel, sd->id, sd->lun);
 391        return 0;
 392}
 393
 394/*
 395 * Called with struct Scsi_Host->host_lock called.
 396 */
 397static int pscsi_create_type_nondisk(struct se_device *dev, struct scsi_device *sd)
 398        __releases(sh->host_lock)
 399{
 400        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 401        struct Scsi_Host *sh = sd->host;
 402        int ret;
 403
 404        if (scsi_device_get(sd)) {
 405                pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 406                        sh->host_no, sd->channel, sd->id, sd->lun);
 407                spin_unlock_irq(sh->host_lock);
 408                return -EIO;
 409        }
 410        spin_unlock_irq(sh->host_lock);
 411
 412        ret = pscsi_add_device_to_list(dev, sd);
 413        if (ret) {
 414                scsi_device_put(sd);
 415                return ret;
 416        }
 417        pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
 418                phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
 419                sd->channel, sd->id, sd->lun);
 420
 421        return 0;
 422}
 423
 424static int pscsi_configure_device(struct se_device *dev)
 425{
 426        struct se_hba *hba = dev->se_hba;
 427        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 428        struct scsi_device *sd;
 429        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 430        struct Scsi_Host *sh = phv->phv_lld_host;
 431        int legacy_mode_enable = 0;
 432        int ret;
 433
 434        if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
 435            !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
 436            !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
 437                pr_err("Missing scsi_channel_id=, scsi_target_id= and"
 438                        " scsi_lun_id= parameters\n");
 439                return -EINVAL;
 440        }
 441
 442        /*
 443         * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
 444         * struct Scsi_Host we will need to bring the TCM/pSCSI object online
 445         */
 446        if (!sh) {
 447                if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 448                        pr_err("pSCSI: Unable to locate struct"
 449                                " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
 450                        return -ENODEV;
 451                }
 452                /*
 453                 * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
 454                 * reference, we enforce that udev_path has been set
 455                 */
 456                if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
 457                        pr_err("pSCSI: udev_path attribute has not"
 458                                " been set before ENABLE=1\n");
 459                        return -EINVAL;
 460                }
 461                /*
 462                 * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
 463                 * use the original TCM hba ID to reference Linux/SCSI Host No
 464                 * and enable for PHV_LLD_SCSI_HOST_NO mode.
 465                 */
 466                if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
 467                        if (hba->dev_count) {
 468                                pr_err("pSCSI: Unable to set hba_mode"
 469                                        " with active devices\n");
 470                                return -EEXIST;
 471                        }
 472
 473                        if (pscsi_pmode_enable_hba(hba, 1) != 1)
 474                                return -ENODEV;
 475
 476                        legacy_mode_enable = 1;
 477                        hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
 478                        sh = phv->phv_lld_host;
 479                } else {
 480                        sh = scsi_host_lookup(pdv->pdv_host_id);
 481                        if (!sh) {
 482                                pr_err("pSCSI: Unable to locate"
 483                                        " pdv_host_id: %d\n", pdv->pdv_host_id);
 484                                return -EINVAL;
 485                        }
 486                        pdv->pdv_lld_host = sh;
 487                }
 488        } else {
 489                if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
 490                        pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
 491                                " struct Scsi_Host exists\n");
 492                        return -EEXIST;
 493                }
 494        }
 495
 496        spin_lock_irq(sh->host_lock);
 497        list_for_each_entry(sd, &sh->__devices, siblings) {
 498                if ((pdv->pdv_channel_id != sd->channel) ||
 499                    (pdv->pdv_target_id != sd->id) ||
 500                    (pdv->pdv_lun_id != sd->lun))
 501                        continue;
 502                /*
 503                 * Functions will release the held struct scsi_host->host_lock
 504                 * before calling calling pscsi_add_device_to_list() to register
 505                 * struct scsi_device with target_core_mod.
 506                 */
 507                switch (sd->type) {
 508                case TYPE_DISK:
 509                case TYPE_ZBC:
 510                        ret = pscsi_create_type_disk(dev, sd);
 511                        break;
 512                default:
 513                        ret = pscsi_create_type_nondisk(dev, sd);
 514                        break;
 515                }
 516
 517                if (ret) {
 518                        if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 519                                scsi_host_put(sh);
 520                        else if (legacy_mode_enable) {
 521                                pscsi_pmode_enable_hba(hba, 0);
 522                                hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 523                        }
 524                        pdv->pdv_sd = NULL;
 525                        return ret;
 526                }
 527                return 0;
 528        }
 529        spin_unlock_irq(sh->host_lock);
 530
 531        pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
 532                pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
 533
 534        if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 535                scsi_host_put(sh);
 536        else if (legacy_mode_enable) {
 537                pscsi_pmode_enable_hba(hba, 0);
 538                hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 539        }
 540
 541        return -ENODEV;
 542}
 543
 544static void pscsi_dev_call_rcu(struct rcu_head *p)
 545{
 546        struct se_device *dev = container_of(p, struct se_device, rcu_head);
 547        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 548
 549        kfree(pdv);
 550}
 551
 552static void pscsi_free_device(struct se_device *dev)
 553{
 554        call_rcu(&dev->rcu_head, pscsi_dev_call_rcu);
 555}
 556
 557static void pscsi_destroy_device(struct se_device *dev)
 558{
 559        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 560        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 561        struct scsi_device *sd = pdv->pdv_sd;
 562
 563        if (sd) {
 564                /*
 565                 * Release exclusive pSCSI internal struct block_device claim for
 566                 * struct scsi_device with TYPE_DISK or TYPE_ZBC
 567                 * from pscsi_create_type_disk()
 568                 */
 569                if ((sd->type == TYPE_DISK || sd->type == TYPE_ZBC) &&
 570                    pdv->pdv_bd) {
 571                        blkdev_put(pdv->pdv_bd,
 572                                   FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 573                        pdv->pdv_bd = NULL;
 574                }
 575                /*
 576                 * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
 577                 * to struct Scsi_Host now.
 578                 */
 579                if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
 580                    (phv->phv_lld_host != NULL))
 581                        scsi_host_put(phv->phv_lld_host);
 582                else if (pdv->pdv_lld_host)
 583                        scsi_host_put(pdv->pdv_lld_host);
 584
 585                scsi_device_put(sd);
 586
 587                pdv->pdv_sd = NULL;
 588        }
 589}
 590
 591static void pscsi_complete_cmd(struct se_cmd *cmd, u8 scsi_status,
 592                               unsigned char *req_sense)
 593{
 594        struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 595        struct scsi_device *sd = pdv->pdv_sd;
 596        struct pscsi_plugin_task *pt = cmd->priv;
 597        unsigned char *cdb;
 598        /*
 599         * Special case for REPORT_LUNs handling where pscsi_plugin_task has
 600         * not been allocated because TCM is handling the emulation directly.
 601         */
 602        if (!pt)
 603                return;
 604
 605        cdb = &pt->pscsi_cdb[0];
 606        /*
 607         * Hack to make sure that Write-Protect modepage is set if R/O mode is
 608         * forced.
 609         */
 610        if (!cmd->data_length)
 611                goto after_mode_sense;
 612
 613        if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
 614            scsi_status == SAM_STAT_GOOD) {
 615                bool read_only = target_lun_is_rdonly(cmd);
 616
 617                if (read_only) {
 618                        unsigned char *buf;
 619
 620                        buf = transport_kmap_data_sg(cmd);
 621                        if (!buf) {
 622                                ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
 623                        }
 624
 625                        if (cdb[0] == MODE_SENSE_10) {
 626                                if (!(buf[3] & 0x80))
 627                                        buf[3] |= 0x80;
 628                        } else {
 629                                if (!(buf[2] & 0x80))
 630                                        buf[2] |= 0x80;
 631                        }
 632
 633                        transport_kunmap_data_sg(cmd);
 634                }
 635        }
 636after_mode_sense:
 637
 638        if (sd->type != TYPE_TAPE || !cmd->data_length)
 639                goto after_mode_select;
 640
 641        /*
 642         * Hack to correctly obtain the initiator requested blocksize for
 643         * TYPE_TAPE.  Since this value is dependent upon each tape media,
 644         * struct scsi_device->sector_size will not contain the correct value
 645         * by default, so we go ahead and set it so
 646         * TRANSPORT(dev)->get_blockdev() returns the correct value to the
 647         * storage engine.
 648         */
 649        if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
 650             scsi_status == SAM_STAT_GOOD) {
 651                unsigned char *buf;
 652                u16 bdl;
 653                u32 blocksize;
 654
 655                buf = sg_virt(&cmd->t_data_sg[0]);
 656                if (!buf) {
 657                        pr_err("Unable to get buf for scatterlist\n");
 658                        goto after_mode_select;
 659                }
 660
 661                if (cdb[0] == MODE_SELECT)
 662                        bdl = buf[3];
 663                else
 664                        bdl = get_unaligned_be16(&buf[6]);
 665
 666                if (!bdl)
 667                        goto after_mode_select;
 668
 669                if (cdb[0] == MODE_SELECT)
 670                        blocksize = get_unaligned_be24(&buf[9]);
 671                else
 672                        blocksize = get_unaligned_be24(&buf[13]);
 673
 674                sd->sector_size = blocksize;
 675        }
 676after_mode_select:
 677
 678        if (scsi_status == SAM_STAT_CHECK_CONDITION) {
 679                transport_copy_sense_to_cmd(cmd, req_sense);
 680
 681                /*
 682                 * check for TAPE device reads with
 683                 * FM/EOM/ILI set, so that we can get data
 684                 * back despite framework assumption that a
 685                 * check condition means there is no data
 686                 */
 687                if (sd->type == TYPE_TAPE &&
 688                    cmd->data_direction == DMA_FROM_DEVICE) {
 689                        /*
 690                         * is sense data valid, fixed format,
 691                         * and have FM, EOM, or ILI set?
 692                         */
 693                        if (req_sense[0] == 0xf0 &&     /* valid, fixed format */
 694                            req_sense[2] & 0xe0 &&      /* FM, EOM, or ILI */
 695                            (req_sense[2] & 0xf) == 0) { /* key==NO_SENSE */
 696                                pr_debug("Tape FM/EOM/ILI status detected. Treat as normal read.\n");
 697                                cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL;
 698                        }
 699                }
 700        }
 701}
 702
 703enum {
 704        Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
 705        Opt_scsi_lun_id, Opt_err
 706};
 707
 708static match_table_t tokens = {
 709        {Opt_scsi_host_id, "scsi_host_id=%d"},
 710        {Opt_scsi_channel_id, "scsi_channel_id=%d"},
 711        {Opt_scsi_target_id, "scsi_target_id=%d"},
 712        {Opt_scsi_lun_id, "scsi_lun_id=%d"},
 713        {Opt_err, NULL}
 714};
 715
 716static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
 717                const char *page, ssize_t count)
 718{
 719        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 720        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 721        char *orig, *ptr, *opts;
 722        substring_t args[MAX_OPT_ARGS];
 723        int ret = 0, arg, token;
 724
 725        opts = kstrdup(page, GFP_KERNEL);
 726        if (!opts)
 727                return -ENOMEM;
 728
 729        orig = opts;
 730
 731        while ((ptr = strsep(&opts, ",\n")) != NULL) {
 732                if (!*ptr)
 733                        continue;
 734
 735                token = match_token(ptr, tokens, args);
 736                switch (token) {
 737                case Opt_scsi_host_id:
 738                        if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 739                                pr_err("PSCSI[%d]: Unable to accept"
 740                                        " scsi_host_id while phv_mode =="
 741                                        " PHV_LLD_SCSI_HOST_NO\n",
 742                                        phv->phv_host_id);
 743                                ret = -EINVAL;
 744                                goto out;
 745                        }
 746                        ret = match_int(args, &arg);
 747                        if (ret)
 748                                goto out;
 749                        pdv->pdv_host_id = arg;
 750                        pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
 751                                " %d\n", phv->phv_host_id, pdv->pdv_host_id);
 752                        pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
 753                        break;
 754                case Opt_scsi_channel_id:
 755                        ret = match_int(args, &arg);
 756                        if (ret)
 757                                goto out;
 758                        pdv->pdv_channel_id = arg;
 759                        pr_debug("PSCSI[%d]: Referencing SCSI Channel"
 760                                " ID: %d\n",  phv->phv_host_id,
 761                                pdv->pdv_channel_id);
 762                        pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
 763                        break;
 764                case Opt_scsi_target_id:
 765                        ret = match_int(args, &arg);
 766                        if (ret)
 767                                goto out;
 768                        pdv->pdv_target_id = arg;
 769                        pr_debug("PSCSI[%d]: Referencing SCSI Target"
 770                                " ID: %d\n", phv->phv_host_id,
 771                                pdv->pdv_target_id);
 772                        pdv->pdv_flags |= PDF_HAS_TARGET_ID;
 773                        break;
 774                case Opt_scsi_lun_id:
 775                        ret = match_int(args, &arg);
 776                        if (ret)
 777                                goto out;
 778                        pdv->pdv_lun_id = arg;
 779                        pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
 780                                " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
 781                        pdv->pdv_flags |= PDF_HAS_LUN_ID;
 782                        break;
 783                default:
 784                        break;
 785                }
 786        }
 787
 788out:
 789        kfree(orig);
 790        return (!ret) ? count : ret;
 791}
 792
 793static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
 794{
 795        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 796        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 797        struct scsi_device *sd = pdv->pdv_sd;
 798        unsigned char host_id[16];
 799        ssize_t bl;
 800
 801        if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 802                snprintf(host_id, 16, "%d", pdv->pdv_host_id);
 803        else
 804                snprintf(host_id, 16, "PHBA Mode");
 805
 806        bl = sprintf(b, "SCSI Device Bus Location:"
 807                " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
 808                pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
 809                host_id);
 810
 811        if (sd) {
 812                bl += sprintf(b + bl, "        Vendor: %."
 813                        __stringify(INQUIRY_VENDOR_LEN) "s", sd->vendor);
 814                bl += sprintf(b + bl, " Model: %."
 815                        __stringify(INQUIRY_MODEL_LEN) "s", sd->model);
 816                bl += sprintf(b + bl, " Rev: %."
 817                        __stringify(INQUIRY_REVISION_LEN) "s\n", sd->rev);
 818        }
 819        return bl;
 820}
 821
 822static void pscsi_bi_endio(struct bio *bio)
 823{
 824        bio_put(bio);
 825}
 826
 827static inline struct bio *pscsi_get_bio(int nr_vecs)
 828{
 829        struct bio *bio;
 830        /*
 831         * Use bio_malloc() following the comment in for bio -> struct request
 832         * in block/blk-core.c:blk_make_request()
 833         */
 834        bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
 835        if (!bio) {
 836                pr_err("PSCSI: bio_kmalloc() failed\n");
 837                return NULL;
 838        }
 839        bio->bi_end_io = pscsi_bi_endio;
 840
 841        return bio;
 842}
 843
 844static sense_reason_t
 845pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 846                struct request *req)
 847{
 848        struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 849        struct bio *bio = NULL;
 850        struct page *page;
 851        struct scatterlist *sg;
 852        u32 data_len = cmd->data_length, i, len, bytes, off;
 853        int nr_pages = (cmd->data_length + sgl[0].offset +
 854                        PAGE_SIZE - 1) >> PAGE_SHIFT;
 855        int nr_vecs = 0, rc;
 856        int rw = (cmd->data_direction == DMA_TO_DEVICE);
 857
 858        BUG_ON(!cmd->data_length);
 859
 860        pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
 861
 862        for_each_sg(sgl, sg, sgl_nents, i) {
 863                page = sg_page(sg);
 864                off = sg->offset;
 865                len = sg->length;
 866
 867                pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
 868                        page, len, off);
 869
 870                /*
 871                 * We only have one page of data in each sg element,
 872                 * we can not cross a page boundary.
 873                 */
 874                if (off + len > PAGE_SIZE)
 875                        goto fail;
 876
 877                if (len > 0 && data_len > 0) {
 878                        bytes = min_t(unsigned int, len, PAGE_SIZE - off);
 879                        bytes = min(bytes, data_len);
 880
 881                        if (!bio) {
 882new_bio:
 883                                nr_vecs = bio_max_segs(nr_pages);
 884                                /*
 885                                 * Calls bio_kmalloc() and sets bio->bi_end_io()
 886                                 */
 887                                bio = pscsi_get_bio(nr_vecs);
 888                                if (!bio)
 889                                        goto fail;
 890
 891                                if (rw)
 892                                        bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
 893
 894                                pr_debug("PSCSI: Allocated bio: %p,"
 895                                        " dir: %s nr_vecs: %d\n", bio,
 896                                        (rw) ? "rw" : "r", nr_vecs);
 897                        }
 898
 899                        pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
 900                                " bio: %p page: %p len: %d off: %d\n", i, bio,
 901                                page, len, off);
 902
 903                        rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
 904                                        bio, page, bytes, off);
 905                        pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
 906                                bio_segments(bio), nr_vecs);
 907                        if (rc != bytes) {
 908                                pr_debug("PSCSI: Reached bio->bi_vcnt max:"
 909                                        " %d i: %d bio: %p, allocating another"
 910                                        " bio\n", bio->bi_vcnt, i, bio);
 911
 912                                rc = blk_rq_append_bio(req, bio);
 913                                if (rc) {
 914                                        pr_err("pSCSI: failed to append bio\n");
 915                                        goto fail;
 916                                }
 917
 918                                /*
 919                                 * Clear the pointer so that another bio will
 920                                 * be allocated with pscsi_get_bio() above.
 921                                 */
 922                                bio = NULL;
 923                                goto new_bio;
 924                        }
 925
 926                        data_len -= bytes;
 927                }
 928        }
 929
 930        if (bio) {
 931                rc = blk_rq_append_bio(req, bio);
 932                if (rc) {
 933                        pr_err("pSCSI: failed to append bio\n");
 934                        goto fail;
 935                }
 936        }
 937
 938        return 0;
 939fail:
 940        if (bio)
 941                bio_put(bio);
 942        while (req->bio) {
 943                bio = req->bio;
 944                req->bio = bio->bi_next;
 945                bio_put(bio);
 946        }
 947        req->biotail = NULL;
 948        return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 949}
 950
 951static sense_reason_t
 952pscsi_parse_cdb(struct se_cmd *cmd)
 953{
 954        if (cmd->se_cmd_flags & SCF_BIDI)
 955                return TCM_UNSUPPORTED_SCSI_OPCODE;
 956
 957        return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
 958}
 959
 960static sense_reason_t
 961pscsi_execute_cmd(struct se_cmd *cmd)
 962{
 963        struct scatterlist *sgl = cmd->t_data_sg;
 964        u32 sgl_nents = cmd->t_data_nents;
 965        struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 966        struct pscsi_plugin_task *pt;
 967        struct request *req;
 968        sense_reason_t ret;
 969
 970        /*
 971         * Dynamically alloc cdb space, since it may be larger than
 972         * TCM_MAX_COMMAND_SIZE
 973         */
 974        pt = kzalloc(sizeof(*pt) + scsi_command_size(cmd->t_task_cdb), GFP_KERNEL);
 975        if (!pt) {
 976                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 977        }
 978        cmd->priv = pt;
 979
 980        memcpy(pt->pscsi_cdb, cmd->t_task_cdb,
 981                scsi_command_size(cmd->t_task_cdb));
 982
 983        req = blk_get_request(pdv->pdv_sd->request_queue,
 984                        cmd->data_direction == DMA_TO_DEVICE ?
 985                        REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
 986        if (IS_ERR(req)) {
 987                pr_err("PSCSI: blk_get_request() failed\n");
 988                ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 989                goto fail;
 990        }
 991
 992        if (sgl) {
 993                ret = pscsi_map_sg(cmd, sgl, sgl_nents, req);
 994                if (ret)
 995                        goto fail_put_request;
 996        }
 997
 998        req->end_io = pscsi_req_done;
 999        req->end_io_data = cmd;
1000        scsi_req(req)->cmd_len = scsi_command_size(pt->pscsi_cdb);
1001        scsi_req(req)->cmd = &pt->pscsi_cdb[0];
1002        if (pdv->pdv_sd->type == TYPE_DISK ||
1003            pdv->pdv_sd->type == TYPE_ZBC)
1004                req->timeout = PS_TIMEOUT_DISK;
1005        else
1006                req->timeout = PS_TIMEOUT_OTHER;
1007        scsi_req(req)->retries = PS_RETRY;
1008
1009        blk_execute_rq_nowait(NULL, req, (cmd->sam_task_attr == TCM_HEAD_TAG),
1010                        pscsi_req_done);
1011
1012        return 0;
1013
1014fail_put_request:
1015        blk_put_request(req);
1016fail:
1017        kfree(pt);
1018        return ret;
1019}
1020
1021/*      pscsi_get_device_type():
1022 *
1023 *
1024 */
1025static u32 pscsi_get_device_type(struct se_device *dev)
1026{
1027        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1028        struct scsi_device *sd = pdv->pdv_sd;
1029
1030        return (sd) ? sd->type : TYPE_NO_LUN;
1031}
1032
1033static sector_t pscsi_get_blocks(struct se_device *dev)
1034{
1035        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1036
1037        if (pdv->pdv_bd)
1038                return bdev_nr_sectors(pdv->pdv_bd);
1039        return 0;
1040}
1041
1042static void pscsi_req_done(struct request *req, blk_status_t status)
1043{
1044        struct se_cmd *cmd = req->end_io_data;
1045        struct pscsi_plugin_task *pt = cmd->priv;
1046        int result = scsi_req(req)->result;
1047        u8 scsi_status = status_byte(result) << 1;
1048
1049        if (scsi_status != SAM_STAT_GOOD) {
1050                pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1051                        " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1052                        result);
1053        }
1054
1055        pscsi_complete_cmd(cmd, scsi_status, scsi_req(req)->sense);
1056
1057        switch (host_byte(result)) {
1058        case DID_OK:
1059                target_complete_cmd_with_length(cmd, scsi_status,
1060                        cmd->data_length - scsi_req(req)->resid_len);
1061                break;
1062        default:
1063                pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1064                        " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1065                        result);
1066                target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1067                break;
1068        }
1069
1070        blk_put_request(req);
1071        kfree(pt);
1072}
1073
1074static const struct target_backend_ops pscsi_ops = {
1075        .name                   = "pscsi",
1076        .owner                  = THIS_MODULE,
1077        .transport_flags_default = TRANSPORT_FLAG_PASSTHROUGH |
1078                                   TRANSPORT_FLAG_PASSTHROUGH_ALUA |
1079                                   TRANSPORT_FLAG_PASSTHROUGH_PGR,
1080        .attach_hba             = pscsi_attach_hba,
1081        .detach_hba             = pscsi_detach_hba,
1082        .pmode_enable_hba       = pscsi_pmode_enable_hba,
1083        .alloc_device           = pscsi_alloc_device,
1084        .configure_device       = pscsi_configure_device,
1085        .destroy_device         = pscsi_destroy_device,
1086        .free_device            = pscsi_free_device,
1087        .parse_cdb              = pscsi_parse_cdb,
1088        .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1089        .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1090        .get_device_type        = pscsi_get_device_type,
1091        .get_blocks             = pscsi_get_blocks,
1092        .tb_dev_attrib_attrs    = passthrough_attrib_attrs,
1093};
1094
1095static int __init pscsi_module_init(void)
1096{
1097        return transport_backend_register(&pscsi_ops);
1098}
1099
1100static void __exit pscsi_module_exit(void)
1101{
1102        target_backend_unregister(&pscsi_ops);
1103}
1104
1105MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1106MODULE_AUTHOR("nab@Linux-iSCSI.org");
1107MODULE_LICENSE("GPL");
1108
1109module_init(pscsi_module_init);
1110module_exit(pscsi_module_exit);
1111