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