1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /******************************************************************************* 3 * Filename: target_core_iblock.c 4 * 5 * This file contains the Storage Engine <-> Linux BlockIO transport 6 * specific functions. 7 * 8 * (c) Copyright 2003-2013 Datera, Inc. 9 * 10 * Nicholas A. Bellinger <nab@kernel.org> 11 * 12 ******************************************************************************/ 13 14 #include <linux/string.h> 15 #include <linux/parser.h> 16 #include <linux/timer.h> 17 #include <linux/fs.h> 18 #include <linux/blkdev.h> 19 #include <linux/slab.h> 20 #include <linux/spinlock.h> 21 #include <linux/bio.h> 22 #include <linux/genhd.h> 23 #include <linux/file.h> 24 #include <linux/module.h> 25 #include <scsi/scsi_proto.h> 26 #include <asm/unaligned.h> 27 28 #include <target/target_core_base.h> 29 #include <target/target_core_backend.h> 30 31 #include "target_core_iblock.h" 32 33 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */ 34 #define IBLOCK_BIO_POOL_SIZE 128 35 36 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev) 37 { 38 return container_of(dev, struct iblock_dev, dev); 39 } 40 41 42 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 43 { 44 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 45 " Generic Target Core Stack %s\n", hba->hba_id, 46 IBLOCK_VERSION, TARGET_CORE_VERSION); 47 return 0; 48 } 49 50 static void iblock_detach_hba(struct se_hba *hba) 51 { 52 } 53 54 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name) 55 { 56 struct iblock_dev *ib_dev = NULL; 57 58 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 59 if (!ib_dev) { 60 pr_err("Unable to allocate struct iblock_dev\n"); 61 return NULL; 62 } 63 64 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name); 65 66 return &ib_dev->dev; 67 } 68 69 static int iblock_configure_device(struct se_device *dev) 70 { 71 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 72 struct request_queue *q; 73 struct block_device *bd = NULL; 74 struct blk_integrity *bi; 75 fmode_t mode; 76 unsigned int max_write_zeroes_sectors; 77 int ret = -ENOMEM; 78 79 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) { 80 pr_err("Missing udev_path= parameters for IBLOCK\n"); 81 return -EINVAL; 82 } 83 84 ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); 85 if (ret) { 86 pr_err("IBLOCK: Unable to create bioset\n"); 87 goto out; 88 } 89 90 pr_debug( "IBLOCK: Claiming struct block_device: %s\n", 91 ib_dev->ibd_udev_path); 92 93 mode = FMODE_READ|FMODE_EXCL; 94 if (!ib_dev->ibd_readonly) 95 mode |= FMODE_WRITE; 96 else 97 dev->dev_flags |= DF_READ_ONLY; 98 99 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev); 100 if (IS_ERR(bd)) { 101 ret = PTR_ERR(bd); 102 goto out_free_bioset; 103 } 104 ib_dev->ibd_bd = bd; 105 106 q = bdev_get_queue(bd); 107 108 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd); 109 dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q); 110 dev->dev_attrib.hw_queue_depth = q->nr_requests; 111 112 if (target_configure_unmap_from_queue(&dev->dev_attrib, q)) 113 pr_debug("IBLOCK: BLOCK Discard support available," 114 " disabled by default\n"); 115 116 /* 117 * Enable write same emulation for IBLOCK and use 0xFFFF as 118 * the smaller WRITE_SAME(10) only has a two-byte block count. 119 */ 120 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd); 121 if (max_write_zeroes_sectors) 122 dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors; 123 else 124 dev->dev_attrib.max_write_same_len = 0xFFFF; 125 126 if (blk_queue_nonrot(q)) 127 dev->dev_attrib.is_nonrot = 1; 128 129 bi = bdev_get_integrity(bd); 130 if (bi) { 131 struct bio_set *bs = &ib_dev->ibd_bio_set; 132 133 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-IP") || 134 !strcmp(bi->profile->name, "T10-DIF-TYPE1-IP")) { 135 pr_err("IBLOCK export of blk_integrity: %s not" 136 " supported\n", bi->profile->name); 137 ret = -ENOSYS; 138 goto out_blkdev_put; 139 } 140 141 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-CRC")) { 142 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT; 143 } else if (!strcmp(bi->profile->name, "T10-DIF-TYPE1-CRC")) { 144 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT; 145 } 146 147 if (dev->dev_attrib.pi_prot_type) { 148 if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) { 149 pr_err("Unable to allocate bioset for PI\n"); 150 ret = -ENOMEM; 151 goto out_blkdev_put; 152 } 153 pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n", 154 &bs->bio_integrity_pool); 155 } 156 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type; 157 } 158 159 return 0; 160 161 out_blkdev_put: 162 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 163 out_free_bioset: 164 bioset_exit(&ib_dev->ibd_bio_set); 165 out: 166 return ret; 167 } 168 169 static void iblock_dev_call_rcu(struct rcu_head *p) 170 { 171 struct se_device *dev = container_of(p, struct se_device, rcu_head); 172 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 173 174 kfree(ib_dev); 175 } 176 177 static void iblock_free_device(struct se_device *dev) 178 { 179 call_rcu(&dev->rcu_head, iblock_dev_call_rcu); 180 } 181 182 static void iblock_destroy_device(struct se_device *dev) 183 { 184 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 185 186 if (ib_dev->ibd_bd != NULL) 187 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 188 bioset_exit(&ib_dev->ibd_bio_set); 189 } 190 191 static unsigned long long iblock_emulate_read_cap_with_block_size( 192 struct se_device *dev, 193 struct block_device *bd, 194 struct request_queue *q) 195 { 196 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode), 197 bdev_logical_block_size(bd)) - 1); 198 u32 block_size = bdev_logical_block_size(bd); 199 200 if (block_size == dev->dev_attrib.block_size) 201 return blocks_long; 202 203 switch (block_size) { 204 case 4096: 205 switch (dev->dev_attrib.block_size) { 206 case 2048: 207 blocks_long <<= 1; 208 break; 209 case 1024: 210 blocks_long <<= 2; 211 break; 212 case 512: 213 blocks_long <<= 3; 214 break; 215 default: 216 break; 217 } 218 break; 219 case 2048: 220 switch (dev->dev_attrib.block_size) { 221 case 4096: 222 blocks_long >>= 1; 223 break; 224 case 1024: 225 blocks_long <<= 1; 226 break; 227 case 512: 228 blocks_long <<= 2; 229 break; 230 default: 231 break; 232 } 233 break; 234 case 1024: 235 switch (dev->dev_attrib.block_size) { 236 case 4096: 237 blocks_long >>= 2; 238 break; 239 case 2048: 240 blocks_long >>= 1; 241 break; 242 case 512: 243 blocks_long <<= 1; 244 break; 245 default: 246 break; 247 } 248 break; 249 case 512: 250 switch (dev->dev_attrib.block_size) { 251 case 4096: 252 blocks_long >>= 3; 253 break; 254 case 2048: 255 blocks_long >>= 2; 256 break; 257 case 1024: 258 blocks_long >>= 1; 259 break; 260 default: 261 break; 262 } 263 break; 264 default: 265 break; 266 } 267 268 return blocks_long; 269 } 270 271 static void iblock_complete_cmd(struct se_cmd *cmd) 272 { 273 struct iblock_req *ibr = cmd->priv; 274 u8 status; 275 276 if (!refcount_dec_and_test(&ibr->pending)) 277 return; 278 279 if (atomic_read(&ibr->ib_bio_err_cnt)) 280 status = SAM_STAT_CHECK_CONDITION; 281 else 282 status = SAM_STAT_GOOD; 283 284 target_complete_cmd(cmd, status); 285 kfree(ibr); 286 } 287 288 static void iblock_bio_done(struct bio *bio) 289 { 290 struct se_cmd *cmd = bio->bi_private; 291 struct iblock_req *ibr = cmd->priv; 292 293 if (bio->bi_status) { 294 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status); 295 /* 296 * Bump the ib_bio_err_cnt and release bio. 297 */ 298 atomic_inc(&ibr->ib_bio_err_cnt); 299 smp_mb__after_atomic(); 300 } 301 302 bio_put(bio); 303 304 iblock_complete_cmd(cmd); 305 } 306 307 static struct bio * 308 iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num, int op, 309 int op_flags) 310 { 311 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 312 struct bio *bio; 313 314 /* 315 * Only allocate as many vector entries as the bio code allows us to, 316 * we'll loop later on until we have handled the whole request. 317 */ 318 bio = bio_alloc_bioset(GFP_NOIO, bio_max_segs(sg_num), 319 &ib_dev->ibd_bio_set); 320 if (!bio) { 321 pr_err("Unable to allocate memory for bio\n"); 322 return NULL; 323 } 324 325 bio_set_dev(bio, ib_dev->ibd_bd); 326 bio->bi_private = cmd; 327 bio->bi_end_io = &iblock_bio_done; 328 bio->bi_iter.bi_sector = lba; 329 bio_set_op_attrs(bio, op, op_flags); 330 331 return bio; 332 } 333 334 static void iblock_submit_bios(struct bio_list *list) 335 { 336 struct blk_plug plug; 337 struct bio *bio; 338 339 blk_start_plug(&plug); 340 while ((bio = bio_list_pop(list))) 341 submit_bio(bio); 342 blk_finish_plug(&plug); 343 } 344 345 static void iblock_end_io_flush(struct bio *bio) 346 { 347 struct se_cmd *cmd = bio->bi_private; 348 349 if (bio->bi_status) 350 pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status); 351 352 if (cmd) { 353 if (bio->bi_status) 354 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION); 355 else 356 target_complete_cmd(cmd, SAM_STAT_GOOD); 357 } 358 359 bio_put(bio); 360 } 361 362 /* 363 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must 364 * always flush the whole cache. 365 */ 366 static sense_reason_t 367 iblock_execute_sync_cache(struct se_cmd *cmd) 368 { 369 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 370 int immed = (cmd->t_task_cdb[1] & 0x2); 371 struct bio *bio; 372 373 /* 374 * If the Immediate bit is set, queue up the GOOD response 375 * for this SYNCHRONIZE_CACHE op. 376 */ 377 if (immed) 378 target_complete_cmd(cmd, SAM_STAT_GOOD); 379 380 bio = bio_alloc(GFP_KERNEL, 0); 381 bio->bi_end_io = iblock_end_io_flush; 382 bio_set_dev(bio, ib_dev->ibd_bd); 383 bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; 384 if (!immed) 385 bio->bi_private = cmd; 386 submit_bio(bio); 387 return 0; 388 } 389 390 static sense_reason_t 391 iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 392 { 393 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 394 struct se_device *dev = cmd->se_dev; 395 int ret; 396 397 ret = blkdev_issue_discard(bdev, 398 target_to_linux_sector(dev, lba), 399 target_to_linux_sector(dev, nolb), 400 GFP_KERNEL, 0); 401 if (ret < 0) { 402 pr_err("blkdev_issue_discard() failed: %d\n", ret); 403 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 404 } 405 406 return 0; 407 } 408 409 static sense_reason_t 410 iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd) 411 { 412 struct se_device *dev = cmd->se_dev; 413 struct scatterlist *sg = &cmd->t_data_sg[0]; 414 unsigned char *buf, *not_zero; 415 int ret; 416 417 buf = kmap(sg_page(sg)) + sg->offset; 418 if (!buf) 419 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 420 /* 421 * Fall back to block_execute_write_same() slow-path if 422 * incoming WRITE_SAME payload does not contain zeros. 423 */ 424 not_zero = memchr_inv(buf, 0x00, cmd->data_length); 425 kunmap(sg_page(sg)); 426 427 if (not_zero) 428 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 429 430 ret = blkdev_issue_zeroout(bdev, 431 target_to_linux_sector(dev, cmd->t_task_lba), 432 target_to_linux_sector(dev, 433 sbc_get_write_same_sectors(cmd)), 434 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); 435 if (ret) 436 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 437 438 target_complete_cmd(cmd, GOOD); 439 return 0; 440 } 441 442 static sense_reason_t 443 iblock_execute_write_same(struct se_cmd *cmd) 444 { 445 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 446 struct iblock_req *ibr; 447 struct scatterlist *sg; 448 struct bio *bio; 449 struct bio_list list; 450 struct se_device *dev = cmd->se_dev; 451 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 452 sector_t sectors = target_to_linux_sector(dev, 453 sbc_get_write_same_sectors(cmd)); 454 455 if (cmd->prot_op) { 456 pr_err("WRITE_SAME: Protection information with IBLOCK" 457 " backends not supported\n"); 458 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 459 } 460 sg = &cmd->t_data_sg[0]; 461 462 if (cmd->t_data_nents > 1 || 463 sg->length != cmd->se_dev->dev_attrib.block_size) { 464 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 465 " block_size: %u\n", cmd->t_data_nents, sg->length, 466 cmd->se_dev->dev_attrib.block_size); 467 return TCM_INVALID_CDB_FIELD; 468 } 469 470 if (bdev_write_zeroes_sectors(bdev)) { 471 if (!iblock_execute_zero_out(bdev, cmd)) 472 return 0; 473 } 474 475 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 476 if (!ibr) 477 goto fail; 478 cmd->priv = ibr; 479 480 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE, 0); 481 if (!bio) 482 goto fail_free_ibr; 483 484 bio_list_init(&list); 485 bio_list_add(&list, bio); 486 487 refcount_set(&ibr->pending, 1); 488 489 while (sectors) { 490 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 491 != sg->length) { 492 493 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE, 494 0); 495 if (!bio) 496 goto fail_put_bios; 497 498 refcount_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 >> SECTOR_SHIFT; 504 sectors -= sg->length >> SECTOR_SHIFT; 505 } 506 507 iblock_submit_bios(&list); 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), 614 "CLAIMED: IBLOCK"); 615 } else { 616 bl += sprintf(b + bl, "Major: 0 Minor: 0\n"); 617 } 618 619 return bl; 620 } 621 622 static int 623 iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio, 624 struct sg_mapping_iter *miter) 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 int rc; 631 size_t resid, len; 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, bio_max_segs(cmd->t_prot_nents)); 640 if (IS_ERR(bip)) { 641 pr_err("Unable to allocate bio_integrity_payload\n"); 642 return PTR_ERR(bip); 643 } 644 645 bip->bip_iter.bi_size = bio_integrity_bytes(bi, bio_sectors(bio)); 646 /* virtual start sector must be in integrity interval units */ 647 bip_set_seed(bip, bio->bi_iter.bi_sector >> 648 (bi->interval_exp - SECTOR_SHIFT)); 649 650 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size, 651 (unsigned long long)bip->bip_iter.bi_sector); 652 653 resid = bip->bip_iter.bi_size; 654 while (resid > 0 && sg_miter_next(miter)) { 655 656 len = min_t(size_t, miter->length, resid); 657 rc = bio_integrity_add_page(bio, miter->page, len, 658 offset_in_page(miter->addr)); 659 if (rc != len) { 660 pr_err("bio_integrity_add_page() failed; %d\n", rc); 661 sg_miter_stop(miter); 662 return -ENOMEM; 663 } 664 665 pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n", 666 miter->page, len, offset_in_page(miter->addr)); 667 668 resid -= len; 669 if (len < miter->length) 670 miter->consumed -= miter->length - len; 671 } 672 sg_miter_stop(miter); 673 674 return 0; 675 } 676 677 static sense_reason_t 678 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 679 enum dma_data_direction data_direction) 680 { 681 struct se_device *dev = cmd->se_dev; 682 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 683 struct iblock_req *ibr; 684 struct bio *bio; 685 struct bio_list list; 686 struct scatterlist *sg; 687 u32 sg_num = sgl_nents; 688 unsigned bio_cnt; 689 int i, rc, op, op_flags = 0; 690 struct sg_mapping_iter prot_miter; 691 692 if (data_direction == DMA_TO_DEVICE) { 693 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 694 struct request_queue *q = bdev_get_queue(ib_dev->ibd_bd); 695 /* 696 * Force writethrough using REQ_FUA if a volatile write cache 697 * is not enabled, or if initiator set the Force Unit Access bit. 698 */ 699 op = REQ_OP_WRITE; 700 if (test_bit(QUEUE_FLAG_FUA, &q->queue_flags)) { 701 if (cmd->se_cmd_flags & SCF_FUA) 702 op_flags = REQ_FUA; 703 else if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) 704 op_flags = REQ_FUA; 705 } 706 } else { 707 op = REQ_OP_READ; 708 } 709 710 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 711 if (!ibr) 712 goto fail; 713 cmd->priv = ibr; 714 715 if (!sgl_nents) { 716 refcount_set(&ibr->pending, 1); 717 iblock_complete_cmd(cmd); 718 return 0; 719 } 720 721 bio = iblock_get_bio(cmd, block_lba, sgl_nents, op, op_flags); 722 if (!bio) 723 goto fail_free_ibr; 724 725 bio_list_init(&list); 726 bio_list_add(&list, bio); 727 728 refcount_set(&ibr->pending, 2); 729 bio_cnt = 1; 730 731 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) 732 sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents, 733 op == REQ_OP_READ ? SG_MITER_FROM_SG : 734 SG_MITER_TO_SG); 735 736 for_each_sg(sgl, sg, sgl_nents, i) { 737 /* 738 * XXX: if the length the device accepts is shorter than the 739 * length of the S/G list entry this will cause and 740 * endless loop. Better hope no driver uses huge pages. 741 */ 742 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 743 != sg->length) { 744 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 745 rc = iblock_alloc_bip(cmd, bio, &prot_miter); 746 if (rc) 747 goto fail_put_bios; 748 } 749 750 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) { 751 iblock_submit_bios(&list); 752 bio_cnt = 0; 753 } 754 755 bio = iblock_get_bio(cmd, block_lba, sg_num, op, 756 op_flags); 757 if (!bio) 758 goto fail_put_bios; 759 760 refcount_inc(&ibr->pending); 761 bio_list_add(&list, bio); 762 bio_cnt++; 763 } 764 765 /* Always in 512 byte units for Linux/Block */ 766 block_lba += sg->length >> SECTOR_SHIFT; 767 sg_num--; 768 } 769 770 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 771 rc = iblock_alloc_bip(cmd, bio, &prot_miter); 772 if (rc) 773 goto fail_put_bios; 774 } 775 776 iblock_submit_bios(&list); 777 iblock_complete_cmd(cmd); 778 return 0; 779 780 fail_put_bios: 781 while ((bio = bio_list_pop(&list))) 782 bio_put(bio); 783 fail_free_ibr: 784 kfree(ibr); 785 fail: 786 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 787 } 788 789 static sector_t iblock_get_blocks(struct se_device *dev) 790 { 791 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 792 struct block_device *bd = ib_dev->ibd_bd; 793 struct request_queue *q = bdev_get_queue(bd); 794 795 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 796 } 797 798 static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev) 799 { 800 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 801 struct block_device *bd = ib_dev->ibd_bd; 802 int ret; 803 804 ret = bdev_alignment_offset(bd); 805 if (ret == -1) 806 return 0; 807 808 /* convert offset-bytes to offset-lbas */ 809 return ret / bdev_logical_block_size(bd); 810 } 811 812 static unsigned int iblock_get_lbppbe(struct se_device *dev) 813 { 814 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 815 struct block_device *bd = ib_dev->ibd_bd; 816 int logs_per_phys = bdev_physical_block_size(bd) / bdev_logical_block_size(bd); 817 818 return ilog2(logs_per_phys); 819 } 820 821 static unsigned int iblock_get_io_min(struct se_device *dev) 822 { 823 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 824 struct block_device *bd = ib_dev->ibd_bd; 825 826 return bdev_io_min(bd); 827 } 828 829 static unsigned int iblock_get_io_opt(struct se_device *dev) 830 { 831 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 832 struct block_device *bd = ib_dev->ibd_bd; 833 834 return bdev_io_opt(bd); 835 } 836 837 static struct sbc_ops iblock_sbc_ops = { 838 .execute_rw = iblock_execute_rw, 839 .execute_sync_cache = iblock_execute_sync_cache, 840 .execute_write_same = iblock_execute_write_same, 841 .execute_unmap = iblock_execute_unmap, 842 }; 843 844 static sense_reason_t 845 iblock_parse_cdb(struct se_cmd *cmd) 846 { 847 return sbc_parse_cdb(cmd, &iblock_sbc_ops); 848 } 849 850 static bool iblock_get_write_cache(struct se_device *dev) 851 { 852 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 853 struct block_device *bd = ib_dev->ibd_bd; 854 struct request_queue *q = bdev_get_queue(bd); 855 856 return test_bit(QUEUE_FLAG_WC, &q->queue_flags); 857 } 858 859 static const struct target_backend_ops iblock_ops = { 860 .name = "iblock", 861 .inquiry_prod = "IBLOCK", 862 .inquiry_rev = IBLOCK_VERSION, 863 .owner = THIS_MODULE, 864 .attach_hba = iblock_attach_hba, 865 .detach_hba = iblock_detach_hba, 866 .alloc_device = iblock_alloc_device, 867 .configure_device = iblock_configure_device, 868 .destroy_device = iblock_destroy_device, 869 .free_device = iblock_free_device, 870 .parse_cdb = iblock_parse_cdb, 871 .set_configfs_dev_params = iblock_set_configfs_dev_params, 872 .show_configfs_dev_params = iblock_show_configfs_dev_params, 873 .get_device_type = sbc_get_device_type, 874 .get_blocks = iblock_get_blocks, 875 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas, 876 .get_lbppbe = iblock_get_lbppbe, 877 .get_io_min = iblock_get_io_min, 878 .get_io_opt = iblock_get_io_opt, 879 .get_write_cache = iblock_get_write_cache, 880 .tb_dev_attrib_attrs = sbc_attrib_attrs, 881 }; 882 883 static int __init iblock_module_init(void) 884 { 885 return transport_backend_register(&iblock_ops); 886 } 887 888 static void __exit iblock_module_exit(void) 889 { 890 target_backend_unregister(&iblock_ops); 891 } 892 893 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 894 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 895 MODULE_LICENSE("GPL"); 896 897 module_init(iblock_module_init); 898 module_exit(iblock_module_exit); 899