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 2003-2012 RisingTide Systems LLC. 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 return 0; 158 159 out_free_bioset: 160 bioset_free(ib_dev->ibd_bio_set); 161 ib_dev->ibd_bio_set = NULL; 162 out: 163 return ret; 164 } 165 166 static void iblock_free_device(struct se_device *dev) 167 { 168 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 169 170 if (ib_dev->ibd_bd != NULL) 171 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 172 if (ib_dev->ibd_bio_set != NULL) 173 bioset_free(ib_dev->ibd_bio_set); 174 kfree(ib_dev); 175 } 176 177 static unsigned long long iblock_emulate_read_cap_with_block_size( 178 struct se_device *dev, 179 struct block_device *bd, 180 struct request_queue *q) 181 { 182 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode), 183 bdev_logical_block_size(bd)) - 1); 184 u32 block_size = bdev_logical_block_size(bd); 185 186 if (block_size == dev->dev_attrib.block_size) 187 return blocks_long; 188 189 switch (block_size) { 190 case 4096: 191 switch (dev->dev_attrib.block_size) { 192 case 2048: 193 blocks_long <<= 1; 194 break; 195 case 1024: 196 blocks_long <<= 2; 197 break; 198 case 512: 199 blocks_long <<= 3; 200 default: 201 break; 202 } 203 break; 204 case 2048: 205 switch (dev->dev_attrib.block_size) { 206 case 4096: 207 blocks_long >>= 1; 208 break; 209 case 1024: 210 blocks_long <<= 1; 211 break; 212 case 512: 213 blocks_long <<= 2; 214 break; 215 default: 216 break; 217 } 218 break; 219 case 1024: 220 switch (dev->dev_attrib.block_size) { 221 case 4096: 222 blocks_long >>= 2; 223 break; 224 case 2048: 225 blocks_long >>= 1; 226 break; 227 case 512: 228 blocks_long <<= 1; 229 break; 230 default: 231 break; 232 } 233 break; 234 case 512: 235 switch (dev->dev_attrib.block_size) { 236 case 4096: 237 blocks_long >>= 3; 238 break; 239 case 2048: 240 blocks_long >>= 2; 241 break; 242 case 1024: 243 blocks_long >>= 1; 244 break; 245 default: 246 break; 247 } 248 break; 249 default: 250 break; 251 } 252 253 return blocks_long; 254 } 255 256 static void iblock_complete_cmd(struct se_cmd *cmd) 257 { 258 struct iblock_req *ibr = cmd->priv; 259 u8 status; 260 261 if (!atomic_dec_and_test(&ibr->pending)) 262 return; 263 264 if (atomic_read(&ibr->ib_bio_err_cnt)) 265 status = SAM_STAT_CHECK_CONDITION; 266 else 267 status = SAM_STAT_GOOD; 268 269 target_complete_cmd(cmd, status); 270 kfree(ibr); 271 } 272 273 static void iblock_bio_done(struct bio *bio, int err) 274 { 275 struct se_cmd *cmd = bio->bi_private; 276 struct iblock_req *ibr = cmd->priv; 277 278 /* 279 * Set -EIO if !BIO_UPTODATE and the passed is still err=0 280 */ 281 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err) 282 err = -EIO; 283 284 if (err != 0) { 285 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p," 286 " err: %d\n", bio, err); 287 /* 288 * Bump the ib_bio_err_cnt and release bio. 289 */ 290 atomic_inc(&ibr->ib_bio_err_cnt); 291 smp_mb__after_atomic_inc(); 292 } 293 294 bio_put(bio); 295 296 iblock_complete_cmd(cmd); 297 } 298 299 static struct bio * 300 iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num) 301 { 302 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 303 struct bio *bio; 304 305 /* 306 * Only allocate as many vector entries as the bio code allows us to, 307 * we'll loop later on until we have handled the whole request. 308 */ 309 if (sg_num > BIO_MAX_PAGES) 310 sg_num = BIO_MAX_PAGES; 311 312 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set); 313 if (!bio) { 314 pr_err("Unable to allocate memory for bio\n"); 315 return NULL; 316 } 317 318 bio->bi_bdev = ib_dev->ibd_bd; 319 bio->bi_private = cmd; 320 bio->bi_end_io = &iblock_bio_done; 321 bio->bi_sector = lba; 322 323 return bio; 324 } 325 326 static void iblock_submit_bios(struct bio_list *list, int rw) 327 { 328 struct blk_plug plug; 329 struct bio *bio; 330 331 blk_start_plug(&plug); 332 while ((bio = bio_list_pop(list))) 333 submit_bio(rw, bio); 334 blk_finish_plug(&plug); 335 } 336 337 static void iblock_end_io_flush(struct bio *bio, int err) 338 { 339 struct se_cmd *cmd = bio->bi_private; 340 341 if (err) 342 pr_err("IBLOCK: cache flush failed: %d\n", err); 343 344 if (cmd) { 345 if (err) 346 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION); 347 else 348 target_complete_cmd(cmd, SAM_STAT_GOOD); 349 } 350 351 bio_put(bio); 352 } 353 354 /* 355 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must 356 * always flush the whole cache. 357 */ 358 static sense_reason_t 359 iblock_execute_sync_cache(struct se_cmd *cmd) 360 { 361 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 362 int immed = (cmd->t_task_cdb[1] & 0x2); 363 struct bio *bio; 364 365 /* 366 * If the Immediate bit is set, queue up the GOOD response 367 * for this SYNCHRONIZE_CACHE op. 368 */ 369 if (immed) 370 target_complete_cmd(cmd, SAM_STAT_GOOD); 371 372 bio = bio_alloc(GFP_KERNEL, 0); 373 bio->bi_end_io = iblock_end_io_flush; 374 bio->bi_bdev = ib_dev->ibd_bd; 375 if (!immed) 376 bio->bi_private = cmd; 377 submit_bio(WRITE_FLUSH, bio); 378 return 0; 379 } 380 381 static sense_reason_t 382 iblock_execute_unmap(struct se_cmd *cmd) 383 { 384 struct se_device *dev = cmd->se_dev; 385 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 386 unsigned char *buf, *ptr = NULL; 387 sector_t lba; 388 int size; 389 u32 range; 390 sense_reason_t ret = 0; 391 int dl, bd_dl, err; 392 393 if (cmd->data_length < 8) { 394 pr_warn("UNMAP parameter list length %u too small\n", 395 cmd->data_length); 396 return TCM_INVALID_PARAMETER_LIST; 397 } 398 399 buf = transport_kmap_data_sg(cmd); 400 if (!buf) 401 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 402 403 dl = get_unaligned_be16(&buf[0]); 404 bd_dl = get_unaligned_be16(&buf[2]); 405 406 size = cmd->data_length - 8; 407 if (bd_dl > size) 408 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n", 409 cmd->data_length, bd_dl); 410 else 411 size = bd_dl; 412 413 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) { 414 ret = TCM_INVALID_PARAMETER_LIST; 415 goto err; 416 } 417 418 /* First UNMAP block descriptor starts at 8 byte offset */ 419 ptr = &buf[8]; 420 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u" 421 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr); 422 423 while (size >= 16) { 424 lba = get_unaligned_be64(&ptr[0]); 425 range = get_unaligned_be32(&ptr[8]); 426 pr_debug("UNMAP: Using lba: %llu and range: %u\n", 427 (unsigned long long)lba, range); 428 429 if (range > dev->dev_attrib.max_unmap_lba_count) { 430 ret = TCM_INVALID_PARAMETER_LIST; 431 goto err; 432 } 433 434 if (lba + range > dev->transport->get_blocks(dev) + 1) { 435 ret = TCM_ADDRESS_OUT_OF_RANGE; 436 goto err; 437 } 438 439 err = blkdev_issue_discard(ib_dev->ibd_bd, lba, range, 440 GFP_KERNEL, 0); 441 if (err < 0) { 442 pr_err("blkdev_issue_discard() failed: %d\n", 443 err); 444 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 445 goto err; 446 } 447 448 ptr += 16; 449 size -= 16; 450 } 451 452 err: 453 transport_kunmap_data_sg(cmd); 454 if (!ret) 455 target_complete_cmd(cmd, GOOD); 456 return ret; 457 } 458 459 static sense_reason_t 460 iblock_execute_write_same_unmap(struct se_cmd *cmd) 461 { 462 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 463 int rc; 464 465 rc = blkdev_issue_discard(ib_dev->ibd_bd, cmd->t_task_lba, 466 spc_get_write_same_sectors(cmd), GFP_KERNEL, 0); 467 if (rc < 0) { 468 pr_warn("blkdev_issue_discard() failed: %d\n", rc); 469 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 470 } 471 472 target_complete_cmd(cmd, GOOD); 473 return 0; 474 } 475 476 static sense_reason_t 477 iblock_execute_write_same(struct se_cmd *cmd) 478 { 479 struct iblock_req *ibr; 480 struct scatterlist *sg; 481 struct bio *bio; 482 struct bio_list list; 483 sector_t block_lba = cmd->t_task_lba; 484 sector_t sectors = spc_get_write_same_sectors(cmd); 485 486 sg = &cmd->t_data_sg[0]; 487 488 if (cmd->t_data_nents > 1 || 489 sg->length != cmd->se_dev->dev_attrib.block_size) { 490 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 491 " block_size: %u\n", cmd->t_data_nents, sg->length, 492 cmd->se_dev->dev_attrib.block_size); 493 return TCM_INVALID_CDB_FIELD; 494 } 495 496 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 497 if (!ibr) 498 goto fail; 499 cmd->priv = ibr; 500 501 bio = iblock_get_bio(cmd, block_lba, 1); 502 if (!bio) 503 goto fail_free_ibr; 504 505 bio_list_init(&list); 506 bio_list_add(&list, bio); 507 508 atomic_set(&ibr->pending, 1); 509 510 while (sectors) { 511 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 512 != sg->length) { 513 514 bio = iblock_get_bio(cmd, block_lba, 1); 515 if (!bio) 516 goto fail_put_bios; 517 518 atomic_inc(&ibr->pending); 519 bio_list_add(&list, bio); 520 } 521 522 /* Always in 512 byte units for Linux/Block */ 523 block_lba += sg->length >> IBLOCK_LBA_SHIFT; 524 sectors -= 1; 525 } 526 527 iblock_submit_bios(&list, WRITE); 528 return 0; 529 530 fail_put_bios: 531 while ((bio = bio_list_pop(&list))) 532 bio_put(bio); 533 fail_free_ibr: 534 kfree(ibr); 535 fail: 536 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 537 } 538 539 enum { 540 Opt_udev_path, Opt_readonly, Opt_force, Opt_err 541 }; 542 543 static match_table_t tokens = { 544 {Opt_udev_path, "udev_path=%s"}, 545 {Opt_readonly, "readonly=%d"}, 546 {Opt_force, "force=%d"}, 547 {Opt_err, NULL} 548 }; 549 550 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev, 551 const char *page, ssize_t count) 552 { 553 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 554 char *orig, *ptr, *arg_p, *opts; 555 substring_t args[MAX_OPT_ARGS]; 556 int ret = 0, token; 557 unsigned long tmp_readonly; 558 559 opts = kstrdup(page, GFP_KERNEL); 560 if (!opts) 561 return -ENOMEM; 562 563 orig = opts; 564 565 while ((ptr = strsep(&opts, ",\n")) != NULL) { 566 if (!*ptr) 567 continue; 568 569 token = match_token(ptr, tokens, args); 570 switch (token) { 571 case Opt_udev_path: 572 if (ib_dev->ibd_bd) { 573 pr_err("Unable to set udev_path= while" 574 " ib_dev->ibd_bd exists\n"); 575 ret = -EEXIST; 576 goto out; 577 } 578 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0], 579 SE_UDEV_PATH_LEN) == 0) { 580 ret = -EINVAL; 581 break; 582 } 583 pr_debug("IBLOCK: Referencing UDEV path: %s\n", 584 ib_dev->ibd_udev_path); 585 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 586 break; 587 case Opt_readonly: 588 arg_p = match_strdup(&args[0]); 589 if (!arg_p) { 590 ret = -ENOMEM; 591 break; 592 } 593 ret = strict_strtoul(arg_p, 0, &tmp_readonly); 594 kfree(arg_p); 595 if (ret < 0) { 596 pr_err("strict_strtoul() failed for" 597 " readonly=\n"); 598 goto out; 599 } 600 ib_dev->ibd_readonly = tmp_readonly; 601 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly); 602 break; 603 case Opt_force: 604 break; 605 default: 606 break; 607 } 608 } 609 610 out: 611 kfree(orig); 612 return (!ret) ? count : ret; 613 } 614 615 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b) 616 { 617 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 618 struct block_device *bd = ib_dev->ibd_bd; 619 char buf[BDEVNAME_SIZE]; 620 ssize_t bl = 0; 621 622 if (bd) 623 bl += sprintf(b + bl, "iBlock device: %s", 624 bdevname(bd, buf)); 625 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH) 626 bl += sprintf(b + bl, " UDEV PATH: %s", 627 ib_dev->ibd_udev_path); 628 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly); 629 630 bl += sprintf(b + bl, " "); 631 if (bd) { 632 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 633 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ? 634 "" : (bd->bd_holder == ib_dev) ? 635 "CLAIMED: IBLOCK" : "CLAIMED: OS"); 636 } else { 637 bl += sprintf(b + bl, "Major: 0 Minor: 0\n"); 638 } 639 640 return bl; 641 } 642 643 static sense_reason_t 644 iblock_execute_rw(struct se_cmd *cmd) 645 { 646 struct scatterlist *sgl = cmd->t_data_sg; 647 u32 sgl_nents = cmd->t_data_nents; 648 enum dma_data_direction data_direction = cmd->data_direction; 649 struct se_device *dev = cmd->se_dev; 650 struct iblock_req *ibr; 651 struct bio *bio; 652 struct bio_list list; 653 struct scatterlist *sg; 654 u32 sg_num = sgl_nents; 655 sector_t block_lba; 656 unsigned bio_cnt; 657 int rw; 658 int i; 659 660 if (data_direction == DMA_TO_DEVICE) { 661 /* 662 * Force data to disk if we pretend to not have a volatile 663 * write cache, or the initiator set the Force Unit Access bit. 664 */ 665 if (dev->dev_attrib.emulate_write_cache == 0 || 666 (dev->dev_attrib.emulate_fua_write > 0 && 667 (cmd->se_cmd_flags & SCF_FUA))) 668 rw = WRITE_FUA; 669 else 670 rw = WRITE; 671 } else { 672 rw = READ; 673 } 674 675 /* 676 * Convert the blocksize advertised to the initiator to the 512 byte 677 * units unconditionally used by the Linux block layer. 678 */ 679 if (dev->dev_attrib.block_size == 4096) 680 block_lba = (cmd->t_task_lba << 3); 681 else if (dev->dev_attrib.block_size == 2048) 682 block_lba = (cmd->t_task_lba << 2); 683 else if (dev->dev_attrib.block_size == 1024) 684 block_lba = (cmd->t_task_lba << 1); 685 else if (dev->dev_attrib.block_size == 512) 686 block_lba = cmd->t_task_lba; 687 else { 688 pr_err("Unsupported SCSI -> BLOCK LBA conversion:" 689 " %u\n", dev->dev_attrib.block_size); 690 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 691 } 692 693 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 694 if (!ibr) 695 goto fail; 696 cmd->priv = ibr; 697 698 if (!sgl_nents) { 699 atomic_set(&ibr->pending, 1); 700 iblock_complete_cmd(cmd); 701 return 0; 702 } 703 704 bio = iblock_get_bio(cmd, block_lba, sgl_nents); 705 if (!bio) 706 goto fail_free_ibr; 707 708 bio_list_init(&list); 709 bio_list_add(&list, bio); 710 711 atomic_set(&ibr->pending, 2); 712 bio_cnt = 1; 713 714 for_each_sg(sgl, sg, sgl_nents, i) { 715 /* 716 * XXX: if the length the device accepts is shorter than the 717 * length of the S/G list entry this will cause and 718 * endless loop. Better hope no driver uses huge pages. 719 */ 720 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 721 != sg->length) { 722 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) { 723 iblock_submit_bios(&list, rw); 724 bio_cnt = 0; 725 } 726 727 bio = iblock_get_bio(cmd, block_lba, sg_num); 728 if (!bio) 729 goto fail_put_bios; 730 731 atomic_inc(&ibr->pending); 732 bio_list_add(&list, bio); 733 bio_cnt++; 734 } 735 736 /* Always in 512 byte units for Linux/Block */ 737 block_lba += sg->length >> IBLOCK_LBA_SHIFT; 738 sg_num--; 739 } 740 741 iblock_submit_bios(&list, rw); 742 iblock_complete_cmd(cmd); 743 return 0; 744 745 fail_put_bios: 746 while ((bio = bio_list_pop(&list))) 747 bio_put(bio); 748 fail_free_ibr: 749 kfree(ibr); 750 fail: 751 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 752 } 753 754 static sector_t iblock_get_blocks(struct se_device *dev) 755 { 756 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 757 struct block_device *bd = ib_dev->ibd_bd; 758 struct request_queue *q = bdev_get_queue(bd); 759 760 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 761 } 762 763 static struct sbc_ops iblock_sbc_ops = { 764 .execute_rw = iblock_execute_rw, 765 .execute_sync_cache = iblock_execute_sync_cache, 766 .execute_write_same = iblock_execute_write_same, 767 .execute_write_same_unmap = iblock_execute_write_same_unmap, 768 .execute_unmap = iblock_execute_unmap, 769 }; 770 771 static sense_reason_t 772 iblock_parse_cdb(struct se_cmd *cmd) 773 { 774 return sbc_parse_cdb(cmd, &iblock_sbc_ops); 775 } 776 777 static struct se_subsystem_api iblock_template = { 778 .name = "iblock", 779 .inquiry_prod = "IBLOCK", 780 .inquiry_rev = IBLOCK_VERSION, 781 .owner = THIS_MODULE, 782 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, 783 .attach_hba = iblock_attach_hba, 784 .detach_hba = iblock_detach_hba, 785 .alloc_device = iblock_alloc_device, 786 .configure_device = iblock_configure_device, 787 .free_device = iblock_free_device, 788 .parse_cdb = iblock_parse_cdb, 789 .set_configfs_dev_params = iblock_set_configfs_dev_params, 790 .show_configfs_dev_params = iblock_show_configfs_dev_params, 791 .get_device_type = sbc_get_device_type, 792 .get_blocks = iblock_get_blocks, 793 }; 794 795 static int __init iblock_module_init(void) 796 { 797 return transport_subsystem_register(&iblock_template); 798 } 799 800 static void iblock_module_exit(void) 801 { 802 transport_subsystem_release(&iblock_template); 803 } 804 805 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 806 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 807 MODULE_LICENSE("GPL"); 808 809 module_init(iblock_module_init); 810 module_exit(iblock_module_exit); 811