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 sense_reason_t 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 && dev->dev_attrib.pi_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); 946