linux/drivers/target/target_core_pscsi.c
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   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 *, blk_status_t);
  59
  60/*      pscsi_attach_hba():
  61 *
  62 *      pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
  63 *      from the passed SCSI Host ID.
  64 */
  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                goto out_free;
 158
 159        memset(cdb, 0, MAX_COMMAND_SIZE);
 160        cdb[0] = MODE_SENSE;
 161        cdb[4] = 0x0c; /* 12 bytes */
 162
 163        ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
 164                        HZ, 1, NULL);
 165        if (ret)
 166                goto out_free;
 167
 168        /*
 169         * If MODE_SENSE still returns zero, set the default value to 1024.
 170         */
 171        sdev->sector_size = get_unaligned_be24(&buf[9]);
 172out_free:
 173        if (!sdev->sector_size)
 174                sdev->sector_size = 1024;
 175
 176        kfree(buf);
 177}
 178
 179static void
 180pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
 181{
 182        unsigned char *buf;
 183
 184        if (sdev->inquiry_len < INQUIRY_LEN)
 185                return;
 186
 187        buf = sdev->inquiry;
 188        if (!buf)
 189                return;
 190        /*
 191         * Use sdev->inquiry from drivers/scsi/scsi_scan.c:scsi_alloc_sdev()
 192         */
 193        memcpy(&wwn->vendor[0], &buf[8], sizeof(wwn->vendor));
 194        memcpy(&wwn->model[0], &buf[16], sizeof(wwn->model));
 195        memcpy(&wwn->revision[0], &buf[32], sizeof(wwn->revision));
 196}
 197
 198static int
 199pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
 200{
 201        unsigned char cdb[MAX_COMMAND_SIZE], *buf;
 202        int ret;
 203
 204        buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
 205        if (!buf)
 206                return -ENOMEM;
 207
 208        memset(cdb, 0, MAX_COMMAND_SIZE);
 209        cdb[0] = INQUIRY;
 210        cdb[1] = 0x01; /* Query VPD */
 211        cdb[2] = 0x80; /* Unit Serial Number */
 212        put_unaligned_be16(INQUIRY_VPD_SERIAL_LEN, &cdb[3]);
 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        put_unaligned_be16(INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, &cdb[3]);
 248
 249        ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
 250                              INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
 251                              NULL, HZ, 1, NULL);
 252        if (ret)
 253                goto out;
 254
 255        page_len = get_unaligned_be16(&buf[2]);
 256        while (page_len > 0) {
 257                /* Grab a pointer to the Identification descriptor */
 258                page_83 = &buf[off];
 259                ident_len = page_83[3];
 260                if (!ident_len) {
 261                        pr_err("page_83[3]: identifier"
 262                                        " length zero!\n");
 263                        break;
 264                }
 265                pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
 266
 267                vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
 268                if (!vpd) {
 269                        pr_err("Unable to allocate memory for"
 270                                        " struct t10_vpd\n");
 271                        goto out;
 272                }
 273                INIT_LIST_HEAD(&vpd->vpd_list);
 274
 275                transport_set_vpd_proto_id(vpd, page_83);
 276                transport_set_vpd_assoc(vpd, page_83);
 277
 278                if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
 279                        off += (ident_len + 4);
 280                        page_len -= (ident_len + 4);
 281                        kfree(vpd);
 282                        continue;
 283                }
 284                if (transport_set_vpd_ident(vpd, page_83) < 0) {
 285                        off += (ident_len + 4);
 286                        page_len -= (ident_len + 4);
 287                        kfree(vpd);
 288                        continue;
 289                }
 290
 291                list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
 292                off += (ident_len + 4);
 293                page_len -= (ident_len + 4);
 294        }
 295
 296out:
 297        kfree(buf);
 298}
 299
 300static int pscsi_add_device_to_list(struct se_device *dev,
 301                struct scsi_device *sd)
 302{
 303        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 304        struct request_queue *q = sd->request_queue;
 305
 306        pdv->pdv_sd = sd;
 307
 308        if (!sd->queue_depth) {
 309                sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
 310
 311                pr_err("Set broken SCSI Device %d:%d:%llu"
 312                        " queue_depth to %d\n", sd->channel, sd->id,
 313                                sd->lun, sd->queue_depth);
 314        }
 315
 316        dev->dev_attrib.hw_block_size =
 317                min_not_zero((int)sd->sector_size, 512);
 318        dev->dev_attrib.hw_max_sectors =
 319                min_not_zero(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                dev->dev_attrib.hw_block_size = sd->sector_size;
 345        }
 346        return 0;
 347}
 348
 349static struct se_device *pscsi_alloc_device(struct se_hba *hba,
 350                const char *name)
 351{
 352        struct pscsi_dev_virt *pdv;
 353
 354        pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
 355        if (!pdv) {
 356                pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
 357                return NULL;
 358        }
 359
 360        pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
 361        return &pdv->dev;
 362}
 363
 364/*
 365 * Called with struct Scsi_Host->host_lock called.
 366 */
 367static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
 368        __releases(sh->host_lock)
 369{
 370        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 371        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 372        struct Scsi_Host *sh = sd->host;
 373        struct block_device *bd;
 374        int ret;
 375
 376        if (scsi_device_get(sd)) {
 377                pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 378                        sh->host_no, sd->channel, sd->id, sd->lun);
 379                spin_unlock_irq(sh->host_lock);
 380                return -EIO;
 381        }
 382        spin_unlock_irq(sh->host_lock);
 383        /*
 384         * Claim exclusive struct block_device access to struct scsi_device
 385         * for TYPE_DISK and TYPE_ZBC using supplied udev_path
 386         */
 387        bd = blkdev_get_by_path(dev->udev_path,
 388                                FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
 389        if (IS_ERR(bd)) {
 390                pr_err("pSCSI: blkdev_get_by_path() failed\n");
 391                scsi_device_put(sd);
 392                return PTR_ERR(bd);
 393        }
 394        pdv->pdv_bd = bd;
 395
 396        ret = pscsi_add_device_to_list(dev, sd);
 397        if (ret) {
 398                blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 399                scsi_device_put(sd);
 400                return ret;
 401        }
 402
 403        pr_debug("CORE_PSCSI[%d] - Added TYPE_%s for %d:%d:%d:%llu\n",
 404                phv->phv_host_id, sd->type == TYPE_DISK ? "DISK" : "ZBC",
 405                sh->host_no, sd->channel, sd->id, sd->lun);
 406        return 0;
 407}
 408
 409/*
 410 * Called with struct Scsi_Host->host_lock called.
 411 */
 412static int pscsi_create_type_nondisk(struct se_device *dev, struct scsi_device *sd)
 413        __releases(sh->host_lock)
 414{
 415        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 416        struct Scsi_Host *sh = sd->host;
 417        int ret;
 418
 419        if (scsi_device_get(sd)) {
 420                pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
 421                        sh->host_no, sd->channel, sd->id, sd->lun);
 422                spin_unlock_irq(sh->host_lock);
 423                return -EIO;
 424        }
 425        spin_unlock_irq(sh->host_lock);
 426
 427        ret = pscsi_add_device_to_list(dev, sd);
 428        if (ret) {
 429                scsi_device_put(sd);
 430                return ret;
 431        }
 432        pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
 433                phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
 434                sd->channel, sd->id, sd->lun);
 435
 436        return 0;
 437}
 438
 439static int pscsi_configure_device(struct se_device *dev)
 440{
 441        struct se_hba *hba = dev->se_hba;
 442        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 443        struct scsi_device *sd;
 444        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 445        struct Scsi_Host *sh = phv->phv_lld_host;
 446        int legacy_mode_enable = 0;
 447        int ret;
 448
 449        if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
 450            !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
 451            !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
 452                pr_err("Missing scsi_channel_id=, scsi_target_id= and"
 453                        " scsi_lun_id= parameters\n");
 454                return -EINVAL;
 455        }
 456
 457        /*
 458         * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
 459         * struct Scsi_Host we will need to bring the TCM/pSCSI object online
 460         */
 461        if (!sh) {
 462                if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 463                        pr_err("pSCSI: Unable to locate struct"
 464                                " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
 465                        return -ENODEV;
 466                }
 467                /*
 468                 * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
 469                 * reference, we enforce that udev_path has been set
 470                 */
 471                if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
 472                        pr_err("pSCSI: udev_path attribute has not"
 473                                " been set before ENABLE=1\n");
 474                        return -EINVAL;
 475                }
 476                /*
 477                 * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
 478                 * use the original TCM hba ID to reference Linux/SCSI Host No
 479                 * and enable for PHV_LLD_SCSI_HOST_NO mode.
 480                 */
 481                if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
 482                        if (hba->dev_count) {
 483                                pr_err("pSCSI: Unable to set hba_mode"
 484                                        " with active devices\n");
 485                                return -EEXIST;
 486                        }
 487
 488                        if (pscsi_pmode_enable_hba(hba, 1) != 1)
 489                                return -ENODEV;
 490
 491                        legacy_mode_enable = 1;
 492                        hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
 493                        sh = phv->phv_lld_host;
 494                } else {
 495                        sh = scsi_host_lookup(pdv->pdv_host_id);
 496                        if (!sh) {
 497                                pr_err("pSCSI: Unable to locate"
 498                                        " pdv_host_id: %d\n", pdv->pdv_host_id);
 499                                return -EINVAL;
 500                        }
 501                        pdv->pdv_lld_host = sh;
 502                }
 503        } else {
 504                if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
 505                        pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
 506                                " struct Scsi_Host exists\n");
 507                        return -EEXIST;
 508                }
 509        }
 510
 511        spin_lock_irq(sh->host_lock);
 512        list_for_each_entry(sd, &sh->__devices, siblings) {
 513                if ((pdv->pdv_channel_id != sd->channel) ||
 514                    (pdv->pdv_target_id != sd->id) ||
 515                    (pdv->pdv_lun_id != sd->lun))
 516                        continue;
 517                /*
 518                 * Functions will release the held struct scsi_host->host_lock
 519                 * before calling calling pscsi_add_device_to_list() to register
 520                 * struct scsi_device with target_core_mod.
 521                 */
 522                switch (sd->type) {
 523                case TYPE_DISK:
 524                case TYPE_ZBC:
 525                        ret = pscsi_create_type_disk(dev, sd);
 526                        break;
 527                default:
 528                        ret = pscsi_create_type_nondisk(dev, sd);
 529                        break;
 530                }
 531
 532                if (ret) {
 533                        if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 534                                scsi_host_put(sh);
 535                        else if (legacy_mode_enable) {
 536                                pscsi_pmode_enable_hba(hba, 0);
 537                                hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 538                        }
 539                        pdv->pdv_sd = NULL;
 540                        return ret;
 541                }
 542                return 0;
 543        }
 544        spin_unlock_irq(sh->host_lock);
 545
 546        pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
 547                pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
 548
 549        if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 550                scsi_host_put(sh);
 551        else if (legacy_mode_enable) {
 552                pscsi_pmode_enable_hba(hba, 0);
 553                hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
 554        }
 555
 556        return -ENODEV;
 557}
 558
 559static void pscsi_dev_call_rcu(struct rcu_head *p)
 560{
 561        struct se_device *dev = container_of(p, struct se_device, rcu_head);
 562        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 563
 564        kfree(pdv);
 565}
 566
 567static void pscsi_free_device(struct se_device *dev)
 568{
 569        call_rcu(&dev->rcu_head, pscsi_dev_call_rcu);
 570}
 571
 572static void pscsi_destroy_device(struct se_device *dev)
 573{
 574        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 575        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 576        struct scsi_device *sd = pdv->pdv_sd;
 577
 578        if (sd) {
 579                /*
 580                 * Release exclusive pSCSI internal struct block_device claim for
 581                 * struct scsi_device with TYPE_DISK or TYPE_ZBC
 582                 * from pscsi_create_type_disk()
 583                 */
 584                if ((sd->type == TYPE_DISK || sd->type == TYPE_ZBC) &&
 585                    pdv->pdv_bd) {
 586                        blkdev_put(pdv->pdv_bd,
 587                                   FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 588                        pdv->pdv_bd = NULL;
 589                }
 590                /*
 591                 * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
 592                 * to struct Scsi_Host now.
 593                 */
 594                if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
 595                    (phv->phv_lld_host != NULL))
 596                        scsi_host_put(phv->phv_lld_host);
 597                else if (pdv->pdv_lld_host)
 598                        scsi_host_put(pdv->pdv_lld_host);
 599
 600                scsi_device_put(sd);
 601
 602                pdv->pdv_sd = NULL;
 603        }
 604}
 605
 606static void pscsi_complete_cmd(struct se_cmd *cmd, u8 scsi_status,
 607                               unsigned char *req_sense)
 608{
 609        struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 610        struct scsi_device *sd = pdv->pdv_sd;
 611        struct pscsi_plugin_task *pt = cmd->priv;
 612        unsigned char *cdb;
 613        /*
 614         * Special case for REPORT_LUNs handling where pscsi_plugin_task has
 615         * not been allocated because TCM is handling the emulation directly.
 616         */
 617        if (!pt)
 618                return;
 619
 620        cdb = &pt->pscsi_cdb[0];
 621        /*
 622         * Hack to make sure that Write-Protect modepage is set if R/O mode is
 623         * forced.
 624         */
 625        if (!cmd->data_length)
 626                goto after_mode_sense;
 627
 628        if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
 629            scsi_status == SAM_STAT_GOOD) {
 630                bool read_only = target_lun_is_rdonly(cmd);
 631
 632                if (read_only) {
 633                        unsigned char *buf;
 634
 635                        buf = transport_kmap_data_sg(cmd);
 636                        if (!buf)
 637                                ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
 638
 639                        if (cdb[0] == MODE_SENSE_10) {
 640                                if (!(buf[3] & 0x80))
 641                                        buf[3] |= 0x80;
 642                        } else {
 643                                if (!(buf[2] & 0x80))
 644                                        buf[2] |= 0x80;
 645                        }
 646
 647                        transport_kunmap_data_sg(cmd);
 648                }
 649        }
 650after_mode_sense:
 651
 652        if (sd->type != TYPE_TAPE || !cmd->data_length)
 653                goto after_mode_select;
 654
 655        /*
 656         * Hack to correctly obtain the initiator requested blocksize for
 657         * TYPE_TAPE.  Since this value is dependent upon each tape media,
 658         * struct scsi_device->sector_size will not contain the correct value
 659         * by default, so we go ahead and set it so
 660         * TRANSPORT(dev)->get_blockdev() returns the correct value to the
 661         * storage engine.
 662         */
 663        if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
 664             scsi_status == SAM_STAT_GOOD) {
 665                unsigned char *buf;
 666                u16 bdl;
 667                u32 blocksize;
 668
 669                buf = sg_virt(&cmd->t_data_sg[0]);
 670                if (!buf) {
 671                        pr_err("Unable to get buf for scatterlist\n");
 672                        goto after_mode_select;
 673                }
 674
 675                if (cdb[0] == MODE_SELECT)
 676                        bdl = buf[3];
 677                else
 678                        bdl = get_unaligned_be16(&buf[6]);
 679
 680                if (!bdl)
 681                        goto after_mode_select;
 682
 683                if (cdb[0] == MODE_SELECT)
 684                        blocksize = get_unaligned_be24(&buf[9]);
 685                else
 686                        blocksize = get_unaligned_be24(&buf[13]);
 687
 688                sd->sector_size = blocksize;
 689        }
 690after_mode_select:
 691
 692        if (scsi_status == SAM_STAT_CHECK_CONDITION)
 693                transport_copy_sense_to_cmd(cmd, req_sense);
 694}
 695
 696enum {
 697        Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
 698        Opt_scsi_lun_id, Opt_err
 699};
 700
 701static match_table_t tokens = {
 702        {Opt_scsi_host_id, "scsi_host_id=%d"},
 703        {Opt_scsi_channel_id, "scsi_channel_id=%d"},
 704        {Opt_scsi_target_id, "scsi_target_id=%d"},
 705        {Opt_scsi_lun_id, "scsi_lun_id=%d"},
 706        {Opt_err, NULL}
 707};
 708
 709static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
 710                const char *page, ssize_t count)
 711{
 712        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 713        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 714        char *orig, *ptr, *opts;
 715        substring_t args[MAX_OPT_ARGS];
 716        int ret = 0, arg, token;
 717
 718        opts = kstrdup(page, GFP_KERNEL);
 719        if (!opts)
 720                return -ENOMEM;
 721
 722        orig = opts;
 723
 724        while ((ptr = strsep(&opts, ",\n")) != NULL) {
 725                if (!*ptr)
 726                        continue;
 727
 728                token = match_token(ptr, tokens, args);
 729                switch (token) {
 730                case Opt_scsi_host_id:
 731                        if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
 732                                pr_err("PSCSI[%d]: Unable to accept"
 733                                        " scsi_host_id while phv_mode =="
 734                                        " PHV_LLD_SCSI_HOST_NO\n",
 735                                        phv->phv_host_id);
 736                                ret = -EINVAL;
 737                                goto out;
 738                        }
 739                        ret = match_int(args, &arg);
 740                        if (ret)
 741                                goto out;
 742                        pdv->pdv_host_id = arg;
 743                        pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
 744                                " %d\n", phv->phv_host_id, pdv->pdv_host_id);
 745                        pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
 746                        break;
 747                case Opt_scsi_channel_id:
 748                        ret = match_int(args, &arg);
 749                        if (ret)
 750                                goto out;
 751                        pdv->pdv_channel_id = arg;
 752                        pr_debug("PSCSI[%d]: Referencing SCSI Channel"
 753                                " ID: %d\n",  phv->phv_host_id,
 754                                pdv->pdv_channel_id);
 755                        pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
 756                        break;
 757                case Opt_scsi_target_id:
 758                        ret = match_int(args, &arg);
 759                        if (ret)
 760                                goto out;
 761                        pdv->pdv_target_id = arg;
 762                        pr_debug("PSCSI[%d]: Referencing SCSI Target"
 763                                " ID: %d\n", phv->phv_host_id,
 764                                pdv->pdv_target_id);
 765                        pdv->pdv_flags |= PDF_HAS_TARGET_ID;
 766                        break;
 767                case Opt_scsi_lun_id:
 768                        ret = match_int(args, &arg);
 769                        if (ret)
 770                                goto out;
 771                        pdv->pdv_lun_id = arg;
 772                        pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
 773                                " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
 774                        pdv->pdv_flags |= PDF_HAS_LUN_ID;
 775                        break;
 776                default:
 777                        break;
 778                }
 779        }
 780
 781out:
 782        kfree(orig);
 783        return (!ret) ? count : ret;
 784}
 785
 786static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
 787{
 788        struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 789        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 790        struct scsi_device *sd = pdv->pdv_sd;
 791        unsigned char host_id[16];
 792        ssize_t bl;
 793        int i;
 794
 795        if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
 796                snprintf(host_id, 16, "%d", pdv->pdv_host_id);
 797        else
 798                snprintf(host_id, 16, "PHBA Mode");
 799
 800        bl = sprintf(b, "SCSI Device Bus Location:"
 801                " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
 802                pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
 803                host_id);
 804
 805        if (sd) {
 806                bl += sprintf(b + bl, "        ");
 807                bl += sprintf(b + bl, "Vendor: ");
 808                for (i = 0; i < 8; i++) {
 809                        if (ISPRINT(sd->vendor[i]))   /* printable character? */
 810                                bl += sprintf(b + bl, "%c", sd->vendor[i]);
 811                        else
 812                                bl += sprintf(b + bl, " ");
 813                }
 814                bl += sprintf(b + bl, " Model: ");
 815                for (i = 0; i < 16; i++) {
 816                        if (ISPRINT(sd->model[i]))   /* printable character ? */
 817                                bl += sprintf(b + bl, "%c", sd->model[i]);
 818                        else
 819                                bl += sprintf(b + bl, " ");
 820                }
 821                bl += sprintf(b + bl, " Rev: ");
 822                for (i = 0; i < 4; i++) {
 823                        if (ISPRINT(sd->rev[i]))   /* printable character ? */
 824                                bl += sprintf(b + bl, "%c", sd->rev[i]);
 825                        else
 826                                bl += sprintf(b + bl, " ");
 827                }
 828                bl += sprintf(b + bl, "\n");
 829        }
 830        return bl;
 831}
 832
 833static void pscsi_bi_endio(struct bio *bio)
 834{
 835        bio_put(bio);
 836}
 837
 838static inline struct bio *pscsi_get_bio(int nr_vecs)
 839{
 840        struct bio *bio;
 841        /*
 842         * Use bio_malloc() following the comment in for bio -> struct request
 843         * in block/blk-core.c:blk_make_request()
 844         */
 845        bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
 846        if (!bio) {
 847                pr_err("PSCSI: bio_kmalloc() failed\n");
 848                return NULL;
 849        }
 850        bio->bi_end_io = pscsi_bi_endio;
 851
 852        return bio;
 853}
 854
 855static sense_reason_t
 856pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 857                struct request *req)
 858{
 859        struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 860        struct bio *bio = NULL;
 861        struct page *page;
 862        struct scatterlist *sg;
 863        u32 data_len = cmd->data_length, i, len, bytes, off;
 864        int nr_pages = (cmd->data_length + sgl[0].offset +
 865                        PAGE_SIZE - 1) >> PAGE_SHIFT;
 866        int nr_vecs = 0, rc;
 867        int rw = (cmd->data_direction == DMA_TO_DEVICE);
 868
 869        BUG_ON(!cmd->data_length);
 870
 871        pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
 872
 873        for_each_sg(sgl, sg, sgl_nents, i) {
 874                page = sg_page(sg);
 875                off = sg->offset;
 876                len = sg->length;
 877
 878                pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
 879                        page, len, off);
 880
 881                /*
 882                 * We only have one page of data in each sg element,
 883                 * we can not cross a page boundary.
 884                 */
 885                if (off + len > PAGE_SIZE)
 886                        goto fail;
 887
 888                if (len > 0 && data_len > 0) {
 889                        bytes = min_t(unsigned int, len, PAGE_SIZE - off);
 890                        bytes = min(bytes, data_len);
 891
 892                        if (!bio) {
 893new_bio:
 894                                nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
 895                                nr_pages -= nr_vecs;
 896                                /*
 897                                 * Calls bio_kmalloc() and sets bio->bi_end_io()
 898                                 */
 899                                bio = pscsi_get_bio(nr_vecs);
 900                                if (!bio)
 901                                        goto fail;
 902
 903                                if (rw)
 904                                        bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
 905
 906                                pr_debug("PSCSI: Allocated bio: %p,"
 907                                        " dir: %s nr_vecs: %d\n", bio,
 908                                        (rw) ? "rw" : "r", nr_vecs);
 909                        }
 910
 911                        pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
 912                                " bio: %p page: %p len: %d off: %d\n", i, bio,
 913                                page, len, off);
 914
 915                        rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
 916                                        bio, page, bytes, off);
 917                        pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
 918                                bio_segments(bio), nr_vecs);
 919                        if (rc != bytes) {
 920                                pr_debug("PSCSI: Reached bio->bi_vcnt max:"
 921                                        " %d i: %d bio: %p, allocating another"
 922                                        " bio\n", bio->bi_vcnt, i, bio);
 923
 924                                rc = blk_rq_append_bio(req, &bio);
 925                                if (rc) {
 926                                        pr_err("pSCSI: failed to append bio\n");
 927                                        goto fail;
 928                                }
 929
 930                                /*
 931                                 * Clear the pointer so that another bio will
 932                                 * be allocated with pscsi_get_bio() above.
 933                                 */
 934                                bio = NULL;
 935                                goto new_bio;
 936                        }
 937
 938                        data_len -= bytes;
 939                }
 940        }
 941
 942        if (bio) {
 943                rc = blk_rq_append_bio(req, &bio);
 944                if (rc) {
 945                        pr_err("pSCSI: failed to append bio\n");
 946                        goto fail;
 947                }
 948        }
 949
 950        return 0;
 951fail:
 952        return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 953}
 954
 955static sense_reason_t
 956pscsi_parse_cdb(struct se_cmd *cmd)
 957{
 958        if (cmd->se_cmd_flags & SCF_BIDI)
 959                return TCM_UNSUPPORTED_SCSI_OPCODE;
 960
 961        return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
 962}
 963
 964static sense_reason_t
 965pscsi_execute_cmd(struct se_cmd *cmd)
 966{
 967        struct scatterlist *sgl = cmd->t_data_sg;
 968        u32 sgl_nents = cmd->t_data_nents;
 969        struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
 970        struct pscsi_plugin_task *pt;
 971        struct request *req;
 972        sense_reason_t ret;
 973
 974        /*
 975         * Dynamically alloc cdb space, since it may be larger than
 976         * TCM_MAX_COMMAND_SIZE
 977         */
 978        pt = kzalloc(sizeof(*pt) + scsi_command_size(cmd->t_task_cdb), GFP_KERNEL);
 979        if (!pt) {
 980                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 981        }
 982        cmd->priv = pt;
 983
 984        memcpy(pt->pscsi_cdb, cmd->t_task_cdb,
 985                scsi_command_size(cmd->t_task_cdb));
 986
 987        req = blk_get_request(pdv->pdv_sd->request_queue,
 988                        cmd->data_direction == DMA_TO_DEVICE ?
 989                        REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN,
 990                        GFP_KERNEL);
 991        if (IS_ERR(req)) {
 992                pr_err("PSCSI: blk_get_request() failed\n");
 993                ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 994                goto fail;
 995        }
 996
 997        if (sgl) {
 998                ret = pscsi_map_sg(cmd, sgl, sgl_nents, req);
 999                if (ret)
1000                        goto fail_put_request;
1001        }
1002
1003        req->end_io = pscsi_req_done;
1004        req->end_io_data = cmd;
1005        scsi_req(req)->cmd_len = scsi_command_size(pt->pscsi_cdb);
1006        scsi_req(req)->cmd = &pt->pscsi_cdb[0];
1007        if (pdv->pdv_sd->type == TYPE_DISK ||
1008            pdv->pdv_sd->type == TYPE_ZBC)
1009                req->timeout = PS_TIMEOUT_DISK;
1010        else
1011                req->timeout = PS_TIMEOUT_OTHER;
1012        scsi_req(req)->retries = PS_RETRY;
1013
1014        blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL, req,
1015                        (cmd->sam_task_attr == TCM_HEAD_TAG),
1016                        pscsi_req_done);
1017
1018        return 0;
1019
1020fail_put_request:
1021        blk_put_request(req);
1022fail:
1023        kfree(pt);
1024        return ret;
1025}
1026
1027/*      pscsi_get_device_type():
1028 *
1029 *
1030 */
1031static u32 pscsi_get_device_type(struct se_device *dev)
1032{
1033        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1034        struct scsi_device *sd = pdv->pdv_sd;
1035
1036        return (sd) ? sd->type : TYPE_NO_LUN;
1037}
1038
1039static sector_t pscsi_get_blocks(struct se_device *dev)
1040{
1041        struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1042
1043        if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
1044                return pdv->pdv_bd->bd_part->nr_sects;
1045
1046        return 0;
1047}
1048
1049static void pscsi_req_done(struct request *req, blk_status_t status)
1050{
1051        struct se_cmd *cmd = req->end_io_data;
1052        struct pscsi_plugin_task *pt = cmd->priv;
1053        int result = scsi_req(req)->result;
1054        u8 scsi_status = status_byte(result) << 1;
1055
1056        if (scsi_status) {
1057                pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1058                        " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1059                        result);
1060        }
1061
1062        pscsi_complete_cmd(cmd, scsi_status, scsi_req(req)->sense);
1063
1064        switch (host_byte(result)) {
1065        case DID_OK:
1066                target_complete_cmd(cmd, scsi_status);
1067                break;
1068        default:
1069                pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1070                        " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1071                        result);
1072                target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1073                break;
1074        }
1075
1076        __blk_put_request(req->q, req);
1077        kfree(pt);
1078}
1079
1080static const struct target_backend_ops pscsi_ops = {
1081        .name                   = "pscsi",
1082        .owner                  = THIS_MODULE,
1083        .transport_flags        = TRANSPORT_FLAG_PASSTHROUGH |
1084                                  TRANSPORT_FLAG_PASSTHROUGH_ALUA |
1085                                  TRANSPORT_FLAG_PASSTHROUGH_PGR,
1086        .attach_hba             = pscsi_attach_hba,
1087        .detach_hba             = pscsi_detach_hba,
1088        .pmode_enable_hba       = pscsi_pmode_enable_hba,
1089        .alloc_device           = pscsi_alloc_device,
1090        .configure_device       = pscsi_configure_device,
1091        .destroy_device         = pscsi_destroy_device,
1092        .free_device            = pscsi_free_device,
1093        .parse_cdb              = pscsi_parse_cdb,
1094        .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1095        .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1096        .get_device_type        = pscsi_get_device_type,
1097        .get_blocks             = pscsi_get_blocks,
1098        .tb_dev_attrib_attrs    = passthrough_attrib_attrs,
1099};
1100
1101static int __init pscsi_module_init(void)
1102{
1103        return transport_backend_register(&pscsi_ops);
1104}
1105
1106static void __exit pscsi_module_exit(void)
1107{
1108        target_backend_unregister(&pscsi_ops);
1109}
1110
1111MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1112MODULE_AUTHOR("nab@Linux-iSCSI.org");
1113MODULE_LICENSE("GPL");
1114
1115module_init(pscsi_module_init);
1116module_exit(pscsi_module_exit);
1117