drivers/target/target_core_iblock.c

   1 /*******************************************************************************
   2  * Filename:  target_core_iblock.c
   3  *
   4  * This file contains the Storage Engine  <-> Linux BlockIO transport
   5  * specific functions.
   6  *
   7  * (c) Copyright 2003-2013 Datera, Inc.
   8  *
   9  * Nicholas A. Bellinger <nab@kernel.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24  *
  25  ******************************************************************************/
  26
  27 #include <linux/string.h>
  28 #include <linux/parser.h>
  29 #include <linux/timer.h>
  30 #include <linux/fs.h>
  31 #include <linux/blkdev.h>
  32 #include <linux/slab.h>
  33 #include <linux/spinlock.h>
  34 #include <linux/bio.h>
  35 #include <linux/genhd.h>
  36 #include <linux/file.h>
  37 #include <linux/module.h>
  38 #include <scsi/scsi.h>
  39 #include <scsi/scsi_host.h>
  40 #include <asm/unaligned.h>
  41
  42 #include <target/target_core_base.h>
  43 #include <target/target_core_backend.h>
  44 #include <target/target_core_backend_configfs.h>
  45
  46 #include "target_core_iblock.h"
  47
  48 #define IBLOCK_MAX_BIO_PER_TASK  32     /* max # of bios to submit at a time */
  49 #define IBLOCK_BIO_POOL_SIZE    128
  50
  51 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev)
  52 {
  53         return container_of(dev, struct iblock_dev, dev);
  54 }
  55
  56
  57 static struct se_subsystem_api iblock_template;
  58
  59 /*      iblock_attach_hba(): (Part of se_subsystem_api_t template)
  60  *
  61  *
  62  */
  63 static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
  64 {
  65         pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
  66                 " Generic Target Core Stack %s\n", hba->hba_id,
  67                 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
  68         return 0;
  69 }
  70
  71 static void iblock_detach_hba(struct se_hba *hba)
  72 {
  73 }
  74
  75 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name)
  76 {
  77         struct iblock_dev *ib_dev = NULL;
  78
  79         ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
  80         if (!ib_dev) {
  81                 pr_err("Unable to allocate struct iblock_dev\n");
  82                 return NULL;
  83         }
  84
  85         pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
  86
  87         return &ib_dev->dev;
  88 }
  89
  90 static int iblock_configure_device(struct se_device *dev)
  91 {
  92         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
  93         struct request_queue *q;
  94         struct block_device *bd = NULL;
  95         struct blk_integrity *bi;
  96         fmode_t mode;
  97         int ret = -ENOMEM;
  98
  99         if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) {
 100                 pr_err("Missing udev_path= parameters for IBLOCK\n");
 101                 return -EINVAL;
 102         }
 103
 104         ib_dev->ibd_bio_set = bioset_create(IBLOCK_BIO_POOL_SIZE, 0);
 105         if (!ib_dev->ibd_bio_set) {
 106                 pr_err("IBLOCK: Unable to create bioset\n");
 107                 goto out;
 108         }
 109
 110         pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
 111                         ib_dev->ibd_udev_path);
 112
 113         mode = FMODE_READ|FMODE_EXCL;
 114         if (!ib_dev->ibd_readonly)
 115                 mode |= FMODE_WRITE;
 116
 117         bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev);
 118         if (IS_ERR(bd)) {
 119                 ret = PTR_ERR(bd);
 120                 goto out_free_bioset;
 121         }
 122         ib_dev->ibd_bd = bd;
 123
 124         q = bdev_get_queue(bd);
 125
 126         dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
 127         dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q);
 128         dev->dev_attrib.hw_queue_depth = q->nr_requests;
 129
 130         /*
 131          * Check if the underlying struct block_device request_queue supports
 132          * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
 133          * in ATA and we need to set TPE=1
 134          */
 135         if (blk_queue_discard(q)) {
 136                 dev->dev_attrib.max_unmap_lba_count =
 137                                 q->limits.max_discard_sectors;
 138
 139                 /*
 140                  * Currently hardcoded to 1 in Linux/SCSI code..
 141                  */
 142                 dev->dev_attrib.max_unmap_block_desc_count = 1;
 143                 dev->dev_attrib.unmap_granularity =
 144                                 q->limits.discard_granularity >> 9;
 145                 dev->dev_attrib.unmap_granularity_alignment =
 146                                 q->limits.discard_alignment;
 147
 148                 pr_debug("IBLOCK: BLOCK Discard support available,"
 149                                 " disabled by default\n");
 150         }
 151         /*
 152          * Enable write same emulation for IBLOCK and use 0xFFFF as
 153          * the smaller WRITE_SAME(10) only has a two-byte block count.
 154          */
 155         dev->dev_attrib.max_write_same_len = 0xFFFF;
 156
 157         if (blk_queue_nonrot(q))
 158                 dev->dev_attrib.is_nonrot = 1;
 159
 160         bi = bdev_get_integrity(bd);
 161         if (bi) {
 162                 struct bio_set *bs = ib_dev->ibd_bio_set;
 163
 164                 if (!strcmp(bi->name, "T10-DIF-TYPE3-IP") ||
 165                     !strcmp(bi->name, "T10-DIF-TYPE1-IP")) {
 166                         pr_err("IBLOCK export of blk_integrity: %s not"
 167                                " supported\n", bi->name);
 168                         ret = -ENOSYS;
 169                         goto out_blkdev_put;
 170                 }
 171
 172                 if (!strcmp(bi->name, "T10-DIF-TYPE3-CRC")) {
 173                         dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT;
 174                 } else if (!strcmp(bi->name, "T10-DIF-TYPE1-CRC")) {
 175                         dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT;
 176                 }
 177
 178                 if (dev->dev_attrib.pi_prot_type) {
 179                         if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) {
 180                                 pr_err("Unable to allocate bioset for PI\n");
 181                                 ret = -ENOMEM;
 182                                 goto out_blkdev_put;
 183                         }
 184                         pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n",
 185                                  bs->bio_integrity_pool);
 186                 }
 187                 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type;
 188         }
 189
 190         return 0;
 191
 192 out_blkdev_put:
 193         blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 194 out_free_bioset:
 195         bioset_free(ib_dev->ibd_bio_set);
 196         ib_dev->ibd_bio_set = NULL;
 197 out:
 198         return ret;
 199 }
 200
 201 static void iblock_free_device(struct se_device *dev)
 202 {
 203         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 204
 205         if (ib_dev->ibd_bd != NULL)
 206                 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 207         if (ib_dev->ibd_bio_set != NULL)
 208                 bioset_free(ib_dev->ibd_bio_set);
 209
 210         kfree(ib_dev);
 211 }
 212
 213 static unsigned long long iblock_emulate_read_cap_with_block_size(
 214         struct se_device *dev,
 215         struct block_device *bd,
 216         struct request_queue *q)
 217 {
 218         unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
 219                                         bdev_logical_block_size(bd)) - 1);
 220         u32 block_size = bdev_logical_block_size(bd);
 221
 222         if (block_size == dev->dev_attrib.block_size)
 223                 return blocks_long;
 224
 225         switch (block_size) {
 226         case 4096:
 227                 switch (dev->dev_attrib.block_size) {
 228                 case 2048:
 229                         blocks_long <<= 1;
 230                         break;
 231                 case 1024:
 232                         blocks_long <<= 2;
 233                         break;
 234                 case 512:
 235                         blocks_long <<= 3;
 236                 default:
 237                         break;
 238                 }
 239                 break;
 240         case 2048:
 241                 switch (dev->dev_attrib.block_size) {
 242                 case 4096:
 243                         blocks_long >>= 1;
 244                         break;
 245                 case 1024:
 246                         blocks_long <<= 1;
 247                         break;
 248                 case 512:
 249                         blocks_long <<= 2;
 250                         break;
 251                 default:
 252                         break;
 253                 }
 254                 break;
 255         case 1024:
 256                 switch (dev->dev_attrib.block_size) {
 257                 case 4096:
 258                         blocks_long >>= 2;
 259                         break;
 260                 case 2048:
 261                         blocks_long >>= 1;
 262                         break;
 263                 case 512:
 264                         blocks_long <<= 1;
 265                         break;
 266                 default:
 267                         break;
 268                 }
 269                 break;
 270         case 512:
 271                 switch (dev->dev_attrib.block_size) {
 272                 case 4096:
 273                         blocks_long >>= 3;
 274                         break;
 275                 case 2048:
 276                         blocks_long >>= 2;
 277                         break;
 278                 case 1024:
 279                         blocks_long >>= 1;
 280                         break;
 281                 default:
 282                         break;
 283                 }
 284                 break;
 285         default:
 286                 break;
 287         }
 288
 289         return blocks_long;
 290 }
 291
 292 static void iblock_complete_cmd(struct se_cmd *cmd)
 293 {
 294         struct iblock_req *ibr = cmd->priv;
 295         u8 status;
 296
 297         if (!atomic_dec_and_test(&ibr->pending))
 298                 return;
 299
 300         if (atomic_read(&ibr->ib_bio_err_cnt))
 301                 status = SAM_STAT_CHECK_CONDITION;
 302         else
 303                 status = SAM_STAT_GOOD;
 304
 305         target_complete_cmd(cmd, status);
 306         kfree(ibr);
 307 }
 308
 309 static void iblock_bio_done(struct bio *bio, int err)
 310 {
 311         struct se_cmd *cmd = bio->bi_private;
 312         struct iblock_req *ibr = cmd->priv;
 313
 314         /*
 315          * Set -EIO if !BIO_UPTODATE and the passed is still err=0
 316          */
 317         if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
 318                 err = -EIO;
 319
 320         if (err != 0) {
 321                 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
 322                         " err: %d\n", bio, err);
 323                 /*
 324                  * Bump the ib_bio_err_cnt and release bio.
 325                  */
 326                 atomic_inc(&ibr->ib_bio_err_cnt);
 327                 smp_mb__after_atomic();
 328         }
 329
 330         bio_put(bio);
 331
 332         iblock_complete_cmd(cmd);
 333 }
 334
 335 static struct bio *
 336 iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num)
 337 {
 338         struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
 339         struct bio *bio;
 340
 341         /*
 342          * Only allocate as many vector entries as the bio code allows us to,
 343          * we'll loop later on until we have handled the whole request.
 344          */
 345         if (sg_num > BIO_MAX_PAGES)
 346                 sg_num = BIO_MAX_PAGES;
 347
 348         bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
 349         if (!bio) {
 350                 pr_err("Unable to allocate memory for bio\n");
 351                 return NULL;
 352         }
 353
 354         bio->bi_bdev = ib_dev->ibd_bd;
 355         bio->bi_private = cmd;
 356         bio->bi_end_io = &iblock_bio_done;
 357         bio->bi_iter.bi_sector = lba;
 358
 359         return bio;
 360 }
 361
 362 static void iblock_submit_bios(struct bio_list *list, int rw)
 363 {
 364         struct blk_plug plug;
 365         struct bio *bio;
 366
 367         blk_start_plug(&plug);
 368         while ((bio = bio_list_pop(list)))
 369                 submit_bio(rw, bio);
 370         blk_finish_plug(&plug);
 371 }
 372
 373 static void iblock_end_io_flush(struct bio *bio, int err)
 374 {
 375         struct se_cmd *cmd = bio->bi_private;
 376
 377         if (err)
 378                 pr_err("IBLOCK: cache flush failed: %d\n", err);
 379
 380         if (cmd) {
 381                 if (err)
 382                         target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 383                 else
 384                         target_complete_cmd(cmd, SAM_STAT_GOOD);
 385         }
 386
 387         bio_put(bio);
 388 }
 389
 390 /*
 391  * Implement SYCHRONIZE CACHE.  Note that we can't handle lba ranges and must
 392  * always flush the whole cache.
 393  */
 394 static sense_reason_t
 395 iblock_execute_sync_cache(struct se_cmd *cmd)
 396 {
 397         struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
 398         int immed = (cmd->t_task_cdb[1] & 0x2);
 399         struct bio *bio;
 400
 401         /*
 402          * If the Immediate bit is set, queue up the GOOD response
 403          * for this SYNCHRONIZE_CACHE op.
 404          */
 405         if (immed)
 406                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 407
 408         bio = bio_alloc(GFP_KERNEL, 0);
 409         bio->bi_end_io = iblock_end_io_flush;
 410         bio->bi_bdev = ib_dev->ibd_bd;
 411         if (!immed)
 412                 bio->bi_private = cmd;
 413         submit_bio(WRITE_FLUSH, bio);
 414         return 0;
 415 }
 416
 417 static sense_reason_t
 418 iblock_do_unmap(struct se_cmd *cmd, void *priv,
 419                 sector_t lba, sector_t nolb)
 420 {
 421         struct block_device *bdev = priv;
 422         int ret;
 423
 424         ret = blkdev_issue_discard(bdev, lba, nolb, GFP_KERNEL, 0);
 425         if (ret < 0) {
 426                 pr_err("blkdev_issue_discard() failed: %d\n", ret);
 427                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 428         }
 429
 430         return 0;
 431 }
 432
 433 static sense_reason_t
 434 iblock_execute_unmap(struct se_cmd *cmd)
 435 {
 436         struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
 437
 438         return sbc_execute_unmap(cmd, iblock_do_unmap, bdev);
 439 }
 440
 441 static sense_reason_t
 442 iblock_execute_write_same_unmap(struct se_cmd *cmd)
 443 {
 444         struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
 445         sector_t lba = cmd->t_task_lba;
 446         sector_t nolb = sbc_get_write_same_sectors(cmd);
 447         int ret;
 448
 449         ret = iblock_do_unmap(cmd, bdev, lba, nolb);
 450         if (ret)
 451                 return ret;
 452
 453         target_complete_cmd(cmd, GOOD);
 454         return 0;
 455 }
 456
 457 static sense_reason_t
 458 iblock_execute_write_same(struct se_cmd *cmd)
 459 {
 460         struct iblock_req *ibr;
 461         struct scatterlist *sg;
 462         struct bio *bio;
 463         struct bio_list list;
 464         sector_t block_lba = cmd->t_task_lba;
 465         sector_t sectors = sbc_get_write_same_sectors(cmd);
 466
 467         if (cmd->prot_op) {
 468                 pr_err("WRITE_SAME: Protection information with IBLOCK"
 469                        " backends not supported\n");
 470                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 471         }
 472         sg = &cmd->t_data_sg[0];
 473
 474         if (cmd->t_data_nents > 1 ||
 475             sg->length != cmd->se_dev->dev_attrib.block_size) {
 476                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 477                         " block_size: %u\n", cmd->t_data_nents, sg->length,
 478                         cmd->se_dev->dev_attrib.block_size);
 479                 return TCM_INVALID_CDB_FIELD;
 480         }
 481
 482         ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
 483         if (!ibr)
 484                 goto fail;
 485         cmd->priv = ibr;
 486
 487         bio = iblock_get_bio(cmd, block_lba, 1);
 488         if (!bio)
 489                 goto fail_free_ibr;
 490
 491         bio_list_init(&list);
 492         bio_list_add(&list, bio);
 493
 494         atomic_set(&ibr->pending, 1);
 495
 496         while (sectors) {
 497                 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
 498                                 != sg->length) {
 499
 500                         bio = iblock_get_bio(cmd, block_lba, 1);
 501                         if (!bio)
 502                                 goto fail_put_bios;
 503
 504                         atomic_inc(&ibr->pending);
 505                         bio_list_add(&list, bio);
 506                 }
 507
 508                 /* Always in 512 byte units for Linux/Block */
 509                 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
 510                 sectors -= 1;
 511         }
 512
 513         iblock_submit_bios(&list, WRITE);
 514         return 0;
 515
 516 fail_put_bios:
 517         while ((bio = bio_list_pop(&list)))
 518                 bio_put(bio);
 519 fail_free_ibr:
 520         kfree(ibr);
 521 fail:
 522         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 523 }
 524
 525 enum {
 526         Opt_udev_path, Opt_readonly, Opt_force, Opt_err
 527 };
 528
 529 static match_table_t tokens = {
 530         {Opt_udev_path, "udev_path=%s"},
 531         {Opt_readonly, "readonly=%d"},
 532         {Opt_force, "force=%d"},
 533         {Opt_err, NULL}
 534 };
 535
 536 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
 537                 const char *page, ssize_t count)
 538 {
 539         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 540         char *orig, *ptr, *arg_p, *opts;
 541         substring_t args[MAX_OPT_ARGS];
 542         int ret = 0, token;
 543         unsigned long tmp_readonly;
 544
 545         opts = kstrdup(page, GFP_KERNEL);
 546         if (!opts)
 547                 return -ENOMEM;
 548
 549         orig = opts;
 550
 551         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 552                 if (!*ptr)
 553                         continue;
 554
 555                 token = match_token(ptr, tokens, args);
 556                 switch (token) {
 557                 case Opt_udev_path:
 558                         if (ib_dev->ibd_bd) {
 559                                 pr_err("Unable to set udev_path= while"
 560                                         " ib_dev->ibd_bd exists\n");
 561                                 ret = -EEXIST;
 562                                 goto out;
 563                         }
 564                         if (match_strlcpy(ib_dev->ibd_udev_path, &args[0],
 565                                 SE_UDEV_PATH_LEN) == 0) {
 566                                 ret = -EINVAL;
 567                                 break;
 568                         }
 569                         pr_debug("IBLOCK: Referencing UDEV path: %s\n",
 570                                         ib_dev->ibd_udev_path);
 571                         ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
 572                         break;
 573                 case Opt_readonly:
 574                         arg_p = match_strdup(&args[0]);
 575                         if (!arg_p) {
 576                                 ret = -ENOMEM;
 577                                 break;
 578                         }
 579                         ret = kstrtoul(arg_p, 0, &tmp_readonly);
 580                         kfree(arg_p);
 581                         if (ret < 0) {
 582                                 pr_err("kstrtoul() failed for"
 583                                                 " readonly=\n");
 584                                 goto out;
 585                         }
 586                         ib_dev->ibd_readonly = tmp_readonly;
 587                         pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
 588                         break;
 589                 case Opt_force:
 590                         break;
 591                 default:
 592                         break;
 593                 }
 594         }
 595
 596 out:
 597         kfree(orig);
 598         return (!ret) ? count : ret;
 599 }
 600
 601 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
 602 {
 603         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 604         struct block_device *bd = ib_dev->ibd_bd;
 605         char buf[BDEVNAME_SIZE];
 606         ssize_t bl = 0;
 607
 608         if (bd)
 609                 bl += sprintf(b + bl, "iBlock device: %s",
 610                                 bdevname(bd, buf));
 611         if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
 612                 bl += sprintf(b + bl, "  UDEV PATH: %s",
 613                                 ib_dev->ibd_udev_path);
 614         bl += sprintf(b + bl, "  readonly: %d\n", ib_dev->ibd_readonly);
 615
 616         bl += sprintf(b + bl, "        ");
 617         if (bd) {
 618                 bl += sprintf(b + bl, "Major: %d Minor: %d  %s\n",
 619                         MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
 620                         "" : (bd->bd_holder == ib_dev) ?
 621                         "CLAIMED: IBLOCK" : "CLAIMED: OS");
 622         } else {
 623                 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
 624         }
 625
 626         return bl;
 627 }
 628
 629 static int
 630 iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio)
 631 {
 632         struct se_device *dev = cmd->se_dev;
 633         struct blk_integrity *bi;
 634         struct bio_integrity_payload *bip;
 635         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 636         struct scatterlist *sg;
 637         int i, rc;
 638
 639         bi = bdev_get_integrity(ib_dev->ibd_bd);
 640         if (!bi) {
 641                 pr_err("Unable to locate bio_integrity\n");
 642                 return -ENODEV;
 643         }
 644
 645         bip = bio_integrity_alloc(bio, GFP_NOIO, cmd->t_prot_nents);
 646         if (!bip) {
 647                 pr_err("Unable to allocate bio_integrity_payload\n");
 648                 return -ENOMEM;
 649         }
 650
 651         bip->bip_iter.bi_size = (cmd->data_length / dev->dev_attrib.block_size) *
 652                          dev->prot_length;
 653         bip->bip_iter.bi_sector = bio->bi_iter.bi_sector;
 654
 655         pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size,
 656                  (unsigned long long)bip->bip_iter.bi_sector);
 657
 658         for_each_sg(cmd->t_prot_sg, sg, cmd->t_prot_nents, i) {
 659
 660                 rc = bio_integrity_add_page(bio, sg_page(sg), sg->length,
 661                                             sg->offset);
 662                 if (rc != sg->length) {
 663                         pr_err("bio_integrity_add_page() failed; %d\n", rc);
 664                         return -ENOMEM;
 665                 }
 666
 667                 pr_debug("Added bio integrity page: %p length: %d offset; %d\n",
 668                          sg_page(sg), sg->length, sg->offset);
 669         }
 670
 671         return 0;
 672 }
 673
 674 static sense_reason_t
 675 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 676                   enum dma_data_direction data_direction)
 677 {
 678         struct se_device *dev = cmd->se_dev;
 679         struct iblock_req *ibr;
 680         struct bio *bio, *bio_start;
 681         struct bio_list list;
 682         struct scatterlist *sg;
 683         u32 sg_num = sgl_nents;
 684         sector_t block_lba;
 685         unsigned bio_cnt;
 686         int rw = 0;
 687         int i;
 688
 689         if (data_direction == DMA_TO_DEVICE) {
 690                 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 691                 struct request_queue *q = bdev_get_queue(ib_dev->ibd_bd);
 692                 /*
 693                  * Force writethrough using WRITE_FUA if a volatile write cache
 694                  * is not enabled, or if initiator set the Force Unit Access bit.
 695                  */
 696                 if (q->flush_flags & REQ_FUA) {
 697                         if (cmd->se_cmd_flags & SCF_FUA)
 698                                 rw = WRITE_FUA;
 699                         else if (!(q->flush_flags & REQ_FLUSH))
 700                                 rw = WRITE_FUA;
 701                         else
 702                                 rw = WRITE;
 703                 } else {
 704                         rw = WRITE;
 705                 }
 706         } else {
 707                 rw = READ;
 708         }
 709
 710         /*
 711          * Convert the blocksize advertised to the initiator to the 512 byte
 712          * units unconditionally used by the Linux block layer.
 713          */
 714         if (dev->dev_attrib.block_size == 4096)
 715                 block_lba = (cmd->t_task_lba << 3);
 716         else if (dev->dev_attrib.block_size == 2048)
 717                 block_lba = (cmd->t_task_lba << 2);
 718         else if (dev->dev_attrib.block_size == 1024)
 719                 block_lba = (cmd->t_task_lba << 1);
 720         else if (dev->dev_attrib.block_size == 512)
 721                 block_lba = cmd->t_task_lba;
 722         else {
 723                 pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
 724                                 " %u\n", dev->dev_attrib.block_size);
 725                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 726         }
 727
 728         ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
 729         if (!ibr)
 730                 goto fail;
 731         cmd->priv = ibr;
 732
 733         if (!sgl_nents) {
 734                 atomic_set(&ibr->pending, 1);
 735                 iblock_complete_cmd(cmd);
 736                 return 0;
 737         }
 738
 739         bio = iblock_get_bio(cmd, block_lba, sgl_nents);
 740         if (!bio)
 741                 goto fail_free_ibr;
 742
 743         bio_start = bio;
 744         bio_list_init(&list);
 745         bio_list_add(&list, bio);
 746
 747         atomic_set(&ibr->pending, 2);
 748         bio_cnt = 1;
 749
 750         for_each_sg(sgl, sg, sgl_nents, i) {
 751                 /*
 752                  * XXX: if the length the device accepts is shorter than the
 753                  *      length of the S/G list entry this will cause and
 754                  *      endless loop.  Better hope no driver uses huge pages.
 755                  */
 756                 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
 757                                 != sg->length) {
 758                         if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
 759                                 iblock_submit_bios(&list, rw);
 760                                 bio_cnt = 0;
 761                         }
 762
 763                         bio = iblock_get_bio(cmd, block_lba, sg_num);
 764                         if (!bio)
 765                                 goto fail_put_bios;
 766
 767                         atomic_inc(&ibr->pending);
 768                         bio_list_add(&list, bio);
 769                         bio_cnt++;
 770                 }
 771
 772                 /* Always in 512 byte units for Linux/Block */
 773                 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
 774                 sg_num--;
 775         }
 776
 777         if (cmd->prot_type) {
 778                 int rc = iblock_alloc_bip(cmd, bio_start);
 779                 if (rc)
 780                         goto fail_put_bios;
 781         }
 782
 783         iblock_submit_bios(&list, rw);
 784         iblock_complete_cmd(cmd);
 785         return 0;
 786
 787 fail_put_bios:
 788         while ((bio = bio_list_pop(&list)))
 789                 bio_put(bio);
 790 fail_free_ibr:
 791         kfree(ibr);
 792 fail:
 793         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 794 }
 795
 796 static sector_t iblock_get_blocks(struct se_device *dev)
 797 {
 798         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 799         struct block_device *bd = ib_dev->ibd_bd;
 800         struct request_queue *q = bdev_get_queue(bd);
 801
 802         return iblock_emulate_read_cap_with_block_size(dev, bd, q);
 803 }
 804
 805 static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev)
 806 {
 807         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 808         struct block_device *bd = ib_dev->ibd_bd;
 809         int ret;
 810
 811         ret = bdev_alignment_offset(bd);
 812         if (ret == -1)
 813                 return 0;
 814
 815         /* convert offset-bytes to offset-lbas */
 816         return ret / bdev_logical_block_size(bd);
 817 }
 818
 819 static unsigned int iblock_get_lbppbe(struct se_device *dev)
 820 {
 821         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 822         struct block_device *bd = ib_dev->ibd_bd;
 823         int logs_per_phys = bdev_physical_block_size(bd) / bdev_logical_block_size(bd);
 824
 825         return ilog2(logs_per_phys);
 826 }
 827
 828 static unsigned int iblock_get_io_min(struct se_device *dev)
 829 {
 830         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 831         struct block_device *bd = ib_dev->ibd_bd;
 832
 833         return bdev_io_min(bd);
 834 }
 835
 836 static unsigned int iblock_get_io_opt(struct se_device *dev)
 837 {
 838         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 839         struct block_device *bd = ib_dev->ibd_bd;
 840
 841         return bdev_io_opt(bd);
 842 }
 843
 844 static struct sbc_ops iblock_sbc_ops = {
 845         .execute_rw             = iblock_execute_rw,
 846         .execute_sync_cache     = iblock_execute_sync_cache,
 847         .execute_write_same     = iblock_execute_write_same,
 848         .execute_write_same_unmap = iblock_execute_write_same_unmap,
 849         .execute_unmap          = iblock_execute_unmap,
 850 };
 851
 852 static sense_reason_t
 853 iblock_parse_cdb(struct se_cmd *cmd)
 854 {
 855         return sbc_parse_cdb(cmd, &iblock_sbc_ops);
 856 }
 857
 858 static bool iblock_get_write_cache(struct se_device *dev)
 859 {
 860         struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 861         struct block_device *bd = ib_dev->ibd_bd;
 862         struct request_queue *q = bdev_get_queue(bd);
 863
 864         return q->flush_flags & REQ_FLUSH;
 865 }
 866
 867 DEF_TB_DEFAULT_ATTRIBS(iblock);
 868
 869 static struct configfs_attribute *iblock_backend_dev_attrs[] = {
 870         &iblock_dev_attrib_emulate_model_alias.attr,
 871         &iblock_dev_attrib_emulate_dpo.attr,
 872         &iblock_dev_attrib_emulate_fua_write.attr,
 873         &iblock_dev_attrib_emulate_fua_read.attr,
 874         &iblock_dev_attrib_emulate_write_cache.attr,
 875         &iblock_dev_attrib_emulate_ua_intlck_ctrl.attr,
 876         &iblock_dev_attrib_emulate_tas.attr,
 877         &iblock_dev_attrib_emulate_tpu.attr,
 878         &iblock_dev_attrib_emulate_tpws.attr,
 879         &iblock_dev_attrib_emulate_caw.attr,
 880         &iblock_dev_attrib_emulate_3pc.attr,
 881         &iblock_dev_attrib_pi_prot_type.attr,
 882         &iblock_dev_attrib_hw_pi_prot_type.attr,
 883         &iblock_dev_attrib_pi_prot_format.attr,
 884         &iblock_dev_attrib_enforce_pr_isids.attr,
 885         &iblock_dev_attrib_is_nonrot.attr,
 886         &iblock_dev_attrib_emulate_rest_reord.attr,
 887         &iblock_dev_attrib_force_pr_aptpl.attr,
 888         &iblock_dev_attrib_hw_block_size.attr,
 889         &iblock_dev_attrib_block_size.attr,
 890         &iblock_dev_attrib_hw_max_sectors.attr,
 891         &iblock_dev_attrib_optimal_sectors.attr,
 892         &iblock_dev_attrib_hw_queue_depth.attr,
 893         &iblock_dev_attrib_queue_depth.attr,
 894         &iblock_dev_attrib_max_unmap_lba_count.attr,
 895         &iblock_dev_attrib_max_unmap_block_desc_count.attr,
 896         &iblock_dev_attrib_unmap_granularity.attr,
 897         &iblock_dev_attrib_unmap_granularity_alignment.attr,
 898         &iblock_dev_attrib_max_write_same_len.attr,
 899         NULL,
 900 };
 901
 902 static struct se_subsystem_api iblock_template = {
 903         .name                   = "iblock",
 904         .inquiry_prod           = "IBLOCK",
 905         .inquiry_rev            = IBLOCK_VERSION,
 906         .owner                  = THIS_MODULE,
 907         .transport_type         = TRANSPORT_PLUGIN_VHBA_PDEV,
 908         .attach_hba             = iblock_attach_hba,
 909         .detach_hba             = iblock_detach_hba,
 910         .alloc_device           = iblock_alloc_device,
 911         .configure_device       = iblock_configure_device,
 912         .free_device            = iblock_free_device,
 913         .parse_cdb              = iblock_parse_cdb,
 914         .set_configfs_dev_params = iblock_set_configfs_dev_params,
 915         .show_configfs_dev_params = iblock_show_configfs_dev_params,
 916         .get_device_type        = sbc_get_device_type,
 917         .get_blocks             = iblock_get_blocks,
 918         .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas,
 919         .get_lbppbe             = iblock_get_lbppbe,
 920         .get_io_min             = iblock_get_io_min,
 921         .get_io_opt             = iblock_get_io_opt,
 922         .get_write_cache        = iblock_get_write_cache,
 923 };
 924
 925 static int __init iblock_module_init(void)
 926 {
 927         struct target_backend_cits *tbc = &iblock_template.tb_cits;
 928
 929         target_core_setup_sub_cits(&iblock_template);
 930         tbc->tb_dev_attrib_cit.ct_attrs = iblock_backend_dev_attrs;
 931
 932         return transport_subsystem_register(&iblock_template);
 933 }
 934
 935 static void __exit iblock_module_exit(void)
 936 {
 937         transport_subsystem_release(&iblock_template);
 938 }
 939
 940 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
 941 MODULE_AUTHOR("nab@Linux-iSCSI.org");
 942 MODULE_LICENSE("GPL");
 943
 944 module_init(iblock_module_init);
 945 module_exit(iblock_module_exit);