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