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 45 #include "target_core_iblock.h" 46 47 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */ 48 #define IBLOCK_BIO_POOL_SIZE 128 49 50 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev) 51 { 52 return container_of(dev, struct iblock_dev, dev); 53 } 54 55 56 static struct se_subsystem_api iblock_template; 57 58 /* iblock_attach_hba(): (Part of se_subsystem_api_t template) 59 * 60 * 61 */ 62 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 63 { 64 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 65 " Generic Target Core Stack %s\n", hba->hba_id, 66 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION); 67 return 0; 68 } 69 70 static void iblock_detach_hba(struct se_hba *hba) 71 { 72 } 73 74 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name) 75 { 76 struct iblock_dev *ib_dev = NULL; 77 78 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 79 if (!ib_dev) { 80 pr_err("Unable to allocate struct iblock_dev\n"); 81 return NULL; 82 } 83 84 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name); 85 86 return &ib_dev->dev; 87 } 88 89 static int iblock_configure_device(struct se_device *dev) 90 { 91 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 92 struct request_queue *q; 93 struct block_device *bd = NULL; 94 fmode_t mode; 95 int ret = -ENOMEM; 96 97 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) { 98 pr_err("Missing udev_path= parameters for IBLOCK\n"); 99 return -EINVAL; 100 } 101 102 ib_dev->ibd_bio_set = bioset_create(IBLOCK_BIO_POOL_SIZE, 0); 103 if (!ib_dev->ibd_bio_set) { 104 pr_err("IBLOCK: Unable to create bioset\n"); 105 goto out; 106 } 107 108 pr_debug( "IBLOCK: Claiming struct block_device: %s\n", 109 ib_dev->ibd_udev_path); 110 111 mode = FMODE_READ|FMODE_EXCL; 112 if (!ib_dev->ibd_readonly) 113 mode |= FMODE_WRITE; 114 115 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev); 116 if (IS_ERR(bd)) { 117 ret = PTR_ERR(bd); 118 goto out_free_bioset; 119 } 120 ib_dev->ibd_bd = bd; 121 122 q = bdev_get_queue(bd); 123 124 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd); 125 dev->dev_attrib.hw_max_sectors = UINT_MAX; 126 dev->dev_attrib.hw_queue_depth = q->nr_requests; 127 128 /* 129 * Check if the underlying struct block_device request_queue supports 130 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM 131 * in ATA and we need to set TPE=1 132 */ 133 if (blk_queue_discard(q)) { 134 dev->dev_attrib.max_unmap_lba_count = 135 q->limits.max_discard_sectors; 136 137 /* 138 * Currently hardcoded to 1 in Linux/SCSI code.. 139 */ 140 dev->dev_attrib.max_unmap_block_desc_count = 1; 141 dev->dev_attrib.unmap_granularity = 142 q->limits.discard_granularity >> 9; 143 dev->dev_attrib.unmap_granularity_alignment = 144 q->limits.discard_alignment; 145 146 pr_debug("IBLOCK: BLOCK Discard support available," 147 " disabled by default\n"); 148 } 149 /* 150 * Enable write same emulation for IBLOCK and use 0xFFFF as 151 * the smaller WRITE_SAME(10) only has a two-byte block count. 152 */ 153 dev->dev_attrib.max_write_same_len = 0xFFFF; 154 155 if (blk_queue_nonrot(q)) 156 dev->dev_attrib.is_nonrot = 1; 157 158 return 0; 159 160 out_free_bioset: 161 bioset_free(ib_dev->ibd_bio_set); 162 ib_dev->ibd_bio_set = NULL; 163 out: 164 return ret; 165 } 166 167 static void iblock_free_device(struct se_device *dev) 168 { 169 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 170 171 if (ib_dev->ibd_bd != NULL) 172 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 173 if (ib_dev->ibd_bio_set != NULL) 174 bioset_free(ib_dev->ibd_bio_set); 175 kfree(ib_dev); 176 } 177 178 static unsigned long long iblock_emulate_read_cap_with_block_size( 179 struct se_device *dev, 180 struct block_device *bd, 181 struct request_queue *q) 182 { 183 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode), 184 bdev_logical_block_size(bd)) - 1); 185 u32 block_size = bdev_logical_block_size(bd); 186 187 if (block_size == dev->dev_attrib.block_size) 188 return blocks_long; 189 190 switch (block_size) { 191 case 4096: 192 switch (dev->dev_attrib.block_size) { 193 case 2048: 194 blocks_long <<= 1; 195 break; 196 case 1024: 197 blocks_long <<= 2; 198 break; 199 case 512: 200 blocks_long <<= 3; 201 default: 202 break; 203 } 204 break; 205 case 2048: 206 switch (dev->dev_attrib.block_size) { 207 case 4096: 208 blocks_long >>= 1; 209 break; 210 case 1024: 211 blocks_long <<= 1; 212 break; 213 case 512: 214 blocks_long <<= 2; 215 break; 216 default: 217 break; 218 } 219 break; 220 case 1024: 221 switch (dev->dev_attrib.block_size) { 222 case 4096: 223 blocks_long >>= 2; 224 break; 225 case 2048: 226 blocks_long >>= 1; 227 break; 228 case 512: 229 blocks_long <<= 1; 230 break; 231 default: 232 break; 233 } 234 break; 235 case 512: 236 switch (dev->dev_attrib.block_size) { 237 case 4096: 238 blocks_long >>= 3; 239 break; 240 case 2048: 241 blocks_long >>= 2; 242 break; 243 case 1024: 244 blocks_long >>= 1; 245 break; 246 default: 247 break; 248 } 249 break; 250 default: 251 break; 252 } 253 254 return blocks_long; 255 } 256 257 static void iblock_complete_cmd(struct se_cmd *cmd) 258 { 259 struct iblock_req *ibr = cmd->priv; 260 u8 status; 261 262 if (!atomic_dec_and_test(&ibr->pending)) 263 return; 264 265 if (atomic_read(&ibr->ib_bio_err_cnt)) 266 status = SAM_STAT_CHECK_CONDITION; 267 else 268 status = SAM_STAT_GOOD; 269 270 target_complete_cmd(cmd, status); 271 kfree(ibr); 272 } 273 274 static void iblock_bio_done(struct bio *bio, int err) 275 { 276 struct se_cmd *cmd = bio->bi_private; 277 struct iblock_req *ibr = cmd->priv; 278 279 /* 280 * Set -EIO if !BIO_UPTODATE and the passed is still err=0 281 */ 282 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err) 283 err = -EIO; 284 285 if (err != 0) { 286 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p," 287 " err: %d\n", bio, err); 288 /* 289 * Bump the ib_bio_err_cnt and release bio. 290 */ 291 atomic_inc(&ibr->ib_bio_err_cnt); 292 smp_mb__after_atomic_inc(); 293 } 294 295 bio_put(bio); 296 297 iblock_complete_cmd(cmd); 298 } 299 300 static struct bio * 301 iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num) 302 { 303 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 304 struct bio *bio; 305 306 /* 307 * Only allocate as many vector entries as the bio code allows us to, 308 * we'll loop later on until we have handled the whole request. 309 */ 310 if (sg_num > BIO_MAX_PAGES) 311 sg_num = BIO_MAX_PAGES; 312 313 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set); 314 if (!bio) { 315 pr_err("Unable to allocate memory for bio\n"); 316 return NULL; 317 } 318 319 bio->bi_bdev = ib_dev->ibd_bd; 320 bio->bi_private = cmd; 321 bio->bi_end_io = &iblock_bio_done; 322 bio->bi_sector = lba; 323 324 return bio; 325 } 326 327 static void iblock_submit_bios(struct bio_list *list, int rw) 328 { 329 struct blk_plug plug; 330 struct bio *bio; 331 332 blk_start_plug(&plug); 333 while ((bio = bio_list_pop(list))) 334 submit_bio(rw, bio); 335 blk_finish_plug(&plug); 336 } 337 338 static void iblock_end_io_flush(struct bio *bio, int err) 339 { 340 struct se_cmd *cmd = bio->bi_private; 341 342 if (err) 343 pr_err("IBLOCK: cache flush failed: %d\n", err); 344 345 if (cmd) { 346 if (err) 347 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION); 348 else 349 target_complete_cmd(cmd, SAM_STAT_GOOD); 350 } 351 352 bio_put(bio); 353 } 354 355 /* 356 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must 357 * always flush the whole cache. 358 */ 359 static sense_reason_t 360 iblock_execute_sync_cache(struct se_cmd *cmd) 361 { 362 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 363 int immed = (cmd->t_task_cdb[1] & 0x2); 364 struct bio *bio; 365 366 /* 367 * If the Immediate bit is set, queue up the GOOD response 368 * for this SYNCHRONIZE_CACHE op. 369 */ 370 if (immed) 371 target_complete_cmd(cmd, SAM_STAT_GOOD); 372 373 bio = bio_alloc(GFP_KERNEL, 0); 374 bio->bi_end_io = iblock_end_io_flush; 375 bio->bi_bdev = ib_dev->ibd_bd; 376 if (!immed) 377 bio->bi_private = cmd; 378 submit_bio(WRITE_FLUSH, bio); 379 return 0; 380 } 381 382 static sense_reason_t 383 iblock_do_unmap(struct se_cmd *cmd, void *priv, 384 sector_t lba, sector_t nolb) 385 { 386 struct block_device *bdev = priv; 387 int ret; 388 389 ret = blkdev_issue_discard(bdev, lba, nolb, GFP_KERNEL, 0); 390 if (ret < 0) { 391 pr_err("blkdev_issue_discard() failed: %d\n", ret); 392 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 393 } 394 395 return 0; 396 } 397 398 static sense_reason_t 399 iblock_execute_unmap(struct se_cmd *cmd) 400 { 401 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 402 403 return sbc_execute_unmap(cmd, iblock_do_unmap, bdev); 404 } 405 406 static sense_reason_t 407 iblock_execute_write_same_unmap(struct se_cmd *cmd) 408 { 409 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 410 sector_t lba = cmd->t_task_lba; 411 sector_t nolb = sbc_get_write_same_sectors(cmd); 412 int ret; 413 414 ret = iblock_do_unmap(cmd, bdev, lba, nolb); 415 if (ret) 416 return ret; 417 418 target_complete_cmd(cmd, GOOD); 419 return 0; 420 } 421 422 static sense_reason_t 423 iblock_execute_write_same(struct se_cmd *cmd) 424 { 425 struct iblock_req *ibr; 426 struct scatterlist *sg; 427 struct bio *bio; 428 struct bio_list list; 429 sector_t block_lba = cmd->t_task_lba; 430 sector_t sectors = sbc_get_write_same_sectors(cmd); 431 432 sg = &cmd->t_data_sg[0]; 433 434 if (cmd->t_data_nents > 1 || 435 sg->length != cmd->se_dev->dev_attrib.block_size) { 436 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 437 " block_size: %u\n", cmd->t_data_nents, sg->length, 438 cmd->se_dev->dev_attrib.block_size); 439 return TCM_INVALID_CDB_FIELD; 440 } 441 442 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 443 if (!ibr) 444 goto fail; 445 cmd->priv = ibr; 446 447 bio = iblock_get_bio(cmd, block_lba, 1); 448 if (!bio) 449 goto fail_free_ibr; 450 451 bio_list_init(&list); 452 bio_list_add(&list, bio); 453 454 atomic_set(&ibr->pending, 1); 455 456 while (sectors) { 457 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 458 != sg->length) { 459 460 bio = iblock_get_bio(cmd, block_lba, 1); 461 if (!bio) 462 goto fail_put_bios; 463 464 atomic_inc(&ibr->pending); 465 bio_list_add(&list, bio); 466 } 467 468 /* Always in 512 byte units for Linux/Block */ 469 block_lba += sg->length >> IBLOCK_LBA_SHIFT; 470 sectors -= 1; 471 } 472 473 iblock_submit_bios(&list, WRITE); 474 return 0; 475 476 fail_put_bios: 477 while ((bio = bio_list_pop(&list))) 478 bio_put(bio); 479 fail_free_ibr: 480 kfree(ibr); 481 fail: 482 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 483 } 484 485 enum { 486 Opt_udev_path, Opt_readonly, Opt_force, Opt_err 487 }; 488 489 static match_table_t tokens = { 490 {Opt_udev_path, "udev_path=%s"}, 491 {Opt_readonly, "readonly=%d"}, 492 {Opt_force, "force=%d"}, 493 {Opt_err, NULL} 494 }; 495 496 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev, 497 const char *page, ssize_t count) 498 { 499 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 500 char *orig, *ptr, *arg_p, *opts; 501 substring_t args[MAX_OPT_ARGS]; 502 int ret = 0, token; 503 unsigned long tmp_readonly; 504 505 opts = kstrdup(page, GFP_KERNEL); 506 if (!opts) 507 return -ENOMEM; 508 509 orig = opts; 510 511 while ((ptr = strsep(&opts, ",\n")) != NULL) { 512 if (!*ptr) 513 continue; 514 515 token = match_token(ptr, tokens, args); 516 switch (token) { 517 case Opt_udev_path: 518 if (ib_dev->ibd_bd) { 519 pr_err("Unable to set udev_path= while" 520 " ib_dev->ibd_bd exists\n"); 521 ret = -EEXIST; 522 goto out; 523 } 524 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0], 525 SE_UDEV_PATH_LEN) == 0) { 526 ret = -EINVAL; 527 break; 528 } 529 pr_debug("IBLOCK: Referencing UDEV path: %s\n", 530 ib_dev->ibd_udev_path); 531 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 532 break; 533 case Opt_readonly: 534 arg_p = match_strdup(&args[0]); 535 if (!arg_p) { 536 ret = -ENOMEM; 537 break; 538 } 539 ret = kstrtoul(arg_p, 0, &tmp_readonly); 540 kfree(arg_p); 541 if (ret < 0) { 542 pr_err("kstrtoul() failed for" 543 " readonly=\n"); 544 goto out; 545 } 546 ib_dev->ibd_readonly = tmp_readonly; 547 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly); 548 break; 549 case Opt_force: 550 break; 551 default: 552 break; 553 } 554 } 555 556 out: 557 kfree(orig); 558 return (!ret) ? count : ret; 559 } 560 561 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b) 562 { 563 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 564 struct block_device *bd = ib_dev->ibd_bd; 565 char buf[BDEVNAME_SIZE]; 566 ssize_t bl = 0; 567 568 if (bd) 569 bl += sprintf(b + bl, "iBlock device: %s", 570 bdevname(bd, buf)); 571 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH) 572 bl += sprintf(b + bl, " UDEV PATH: %s", 573 ib_dev->ibd_udev_path); 574 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly); 575 576 bl += sprintf(b + bl, " "); 577 if (bd) { 578 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 579 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ? 580 "" : (bd->bd_holder == ib_dev) ? 581 "CLAIMED: IBLOCK" : "CLAIMED: OS"); 582 } else { 583 bl += sprintf(b + bl, "Major: 0 Minor: 0\n"); 584 } 585 586 return bl; 587 } 588 589 static sense_reason_t 590 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 591 enum dma_data_direction data_direction) 592 { 593 struct se_device *dev = cmd->se_dev; 594 struct iblock_req *ibr; 595 struct bio *bio; 596 struct bio_list list; 597 struct scatterlist *sg; 598 u32 sg_num = sgl_nents; 599 sector_t block_lba; 600 unsigned bio_cnt; 601 int rw = 0; 602 int i; 603 604 if (data_direction == DMA_TO_DEVICE) { 605 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 606 struct request_queue *q = bdev_get_queue(ib_dev->ibd_bd); 607 /* 608 * Force writethrough using WRITE_FUA if a volatile write cache 609 * is not enabled, or if initiator set the Force Unit Access bit. 610 */ 611 if (q->flush_flags & REQ_FUA) { 612 if (cmd->se_cmd_flags & SCF_FUA) 613 rw = WRITE_FUA; 614 else if (!(q->flush_flags & REQ_FLUSH)) 615 rw = WRITE_FUA; 616 else 617 rw = WRITE; 618 } else { 619 rw = WRITE; 620 } 621 } else { 622 rw = READ; 623 } 624 625 /* 626 * Convert the blocksize advertised to the initiator to the 512 byte 627 * units unconditionally used by the Linux block layer. 628 */ 629 if (dev->dev_attrib.block_size == 4096) 630 block_lba = (cmd->t_task_lba << 3); 631 else if (dev->dev_attrib.block_size == 2048) 632 block_lba = (cmd->t_task_lba << 2); 633 else if (dev->dev_attrib.block_size == 1024) 634 block_lba = (cmd->t_task_lba << 1); 635 else if (dev->dev_attrib.block_size == 512) 636 block_lba = cmd->t_task_lba; 637 else { 638 pr_err("Unsupported SCSI -> BLOCK LBA conversion:" 639 " %u\n", dev->dev_attrib.block_size); 640 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 641 } 642 643 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 644 if (!ibr) 645 goto fail; 646 cmd->priv = ibr; 647 648 if (!sgl_nents) { 649 atomic_set(&ibr->pending, 1); 650 iblock_complete_cmd(cmd); 651 return 0; 652 } 653 654 bio = iblock_get_bio(cmd, block_lba, sgl_nents); 655 if (!bio) 656 goto fail_free_ibr; 657 658 bio_list_init(&list); 659 bio_list_add(&list, bio); 660 661 atomic_set(&ibr->pending, 2); 662 bio_cnt = 1; 663 664 for_each_sg(sgl, sg, sgl_nents, i) { 665 /* 666 * XXX: if the length the device accepts is shorter than the 667 * length of the S/G list entry this will cause and 668 * endless loop. Better hope no driver uses huge pages. 669 */ 670 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 671 != sg->length) { 672 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) { 673 iblock_submit_bios(&list, rw); 674 bio_cnt = 0; 675 } 676 677 bio = iblock_get_bio(cmd, block_lba, sg_num); 678 if (!bio) 679 goto fail_put_bios; 680 681 atomic_inc(&ibr->pending); 682 bio_list_add(&list, bio); 683 bio_cnt++; 684 } 685 686 /* Always in 512 byte units for Linux/Block */ 687 block_lba += sg->length >> IBLOCK_LBA_SHIFT; 688 sg_num--; 689 } 690 691 iblock_submit_bios(&list, rw); 692 iblock_complete_cmd(cmd); 693 return 0; 694 695 fail_put_bios: 696 while ((bio = bio_list_pop(&list))) 697 bio_put(bio); 698 fail_free_ibr: 699 kfree(ibr); 700 fail: 701 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 702 } 703 704 static sector_t iblock_get_blocks(struct se_device *dev) 705 { 706 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 707 struct block_device *bd = ib_dev->ibd_bd; 708 struct request_queue *q = bdev_get_queue(bd); 709 710 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 711 } 712 713 static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev) 714 { 715 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 716 struct block_device *bd = ib_dev->ibd_bd; 717 int ret; 718 719 ret = bdev_alignment_offset(bd); 720 if (ret == -1) 721 return 0; 722 723 /* convert offset-bytes to offset-lbas */ 724 return ret / bdev_logical_block_size(bd); 725 } 726 727 static unsigned int iblock_get_lbppbe(struct se_device *dev) 728 { 729 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 730 struct block_device *bd = ib_dev->ibd_bd; 731 int logs_per_phys = bdev_physical_block_size(bd) / bdev_logical_block_size(bd); 732 733 return ilog2(logs_per_phys); 734 } 735 736 static unsigned int iblock_get_io_min(struct se_device *dev) 737 { 738 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 739 struct block_device *bd = ib_dev->ibd_bd; 740 741 return bdev_io_min(bd); 742 } 743 744 static unsigned int iblock_get_io_opt(struct se_device *dev) 745 { 746 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 747 struct block_device *bd = ib_dev->ibd_bd; 748 749 return bdev_io_opt(bd); 750 } 751 752 static struct sbc_ops iblock_sbc_ops = { 753 .execute_rw = iblock_execute_rw, 754 .execute_sync_cache = iblock_execute_sync_cache, 755 .execute_write_same = iblock_execute_write_same, 756 .execute_write_same_unmap = iblock_execute_write_same_unmap, 757 .execute_unmap = iblock_execute_unmap, 758 }; 759 760 static sense_reason_t 761 iblock_parse_cdb(struct se_cmd *cmd) 762 { 763 return sbc_parse_cdb(cmd, &iblock_sbc_ops); 764 } 765 766 bool iblock_get_write_cache(struct se_device *dev) 767 { 768 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 769 struct block_device *bd = ib_dev->ibd_bd; 770 struct request_queue *q = bdev_get_queue(bd); 771 772 return q->flush_flags & REQ_FLUSH; 773 } 774 775 static struct se_subsystem_api iblock_template = { 776 .name = "iblock", 777 .inquiry_prod = "IBLOCK", 778 .inquiry_rev = IBLOCK_VERSION, 779 .owner = THIS_MODULE, 780 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, 781 .attach_hba = iblock_attach_hba, 782 .detach_hba = iblock_detach_hba, 783 .alloc_device = iblock_alloc_device, 784 .configure_device = iblock_configure_device, 785 .free_device = iblock_free_device, 786 .parse_cdb = iblock_parse_cdb, 787 .set_configfs_dev_params = iblock_set_configfs_dev_params, 788 .show_configfs_dev_params = iblock_show_configfs_dev_params, 789 .get_device_type = sbc_get_device_type, 790 .get_blocks = iblock_get_blocks, 791 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas, 792 .get_lbppbe = iblock_get_lbppbe, 793 .get_io_min = iblock_get_io_min, 794 .get_io_opt = iblock_get_io_opt, 795 .get_write_cache = iblock_get_write_cache, 796 }; 797 798 static int __init iblock_module_init(void) 799 { 800 return transport_subsystem_register(&iblock_template); 801 } 802 803 static void __exit iblock_module_exit(void) 804 { 805 transport_subsystem_release(&iblock_template); 806 } 807 808 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 809 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 810 MODULE_LICENSE("GPL"); 811 812 module_init(iblock_module_init); 813 module_exit(iblock_module_exit); 814