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/blk-integrity.h> 20 #include <linux/slab.h> 21 #include <linux/spinlock.h> 22 #include <linux/bio.h> 23 #include <linux/genhd.h> 24 #include <linux/file.h> 25 #include <linux/module.h> 26 #include <linux/scatterlist.h> 27 #include <scsi/scsi_proto.h> 28 #include <asm/unaligned.h> 29 30 #include <target/target_core_base.h> 31 #include <target/target_core_backend.h> 32 33 #include "target_core_iblock.h" 34 35 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */ 36 #define IBLOCK_BIO_POOL_SIZE 128 37 38 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev) 39 { 40 return container_of(dev, struct iblock_dev, dev); 41 } 42 43 44 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 45 { 46 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 47 " Generic Target Core Stack %s\n", hba->hba_id, 48 IBLOCK_VERSION, TARGET_CORE_VERSION); 49 return 0; 50 } 51 52 static void iblock_detach_hba(struct se_hba *hba) 53 { 54 } 55 56 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name) 57 { 58 struct iblock_dev *ib_dev = NULL; 59 60 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 61 if (!ib_dev) { 62 pr_err("Unable to allocate struct iblock_dev\n"); 63 return NULL; 64 } 65 66 ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug), 67 GFP_KERNEL); 68 if (!ib_dev->ibd_plug) 69 goto free_dev; 70 71 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name); 72 73 return &ib_dev->dev; 74 75 free_dev: 76 kfree(ib_dev); 77 return NULL; 78 } 79 80 static int iblock_configure_device(struct se_device *dev) 81 { 82 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 83 struct request_queue *q; 84 struct block_device *bd = NULL; 85 struct blk_integrity *bi; 86 fmode_t mode; 87 unsigned int max_write_zeroes_sectors; 88 int ret; 89 90 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) { 91 pr_err("Missing udev_path= parameters for IBLOCK\n"); 92 return -EINVAL; 93 } 94 95 ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); 96 if (ret) { 97 pr_err("IBLOCK: Unable to create bioset\n"); 98 goto out; 99 } 100 101 pr_debug( "IBLOCK: Claiming struct block_device: %s\n", 102 ib_dev->ibd_udev_path); 103 104 mode = FMODE_READ|FMODE_EXCL; 105 if (!ib_dev->ibd_readonly) 106 mode |= FMODE_WRITE; 107 else 108 dev->dev_flags |= DF_READ_ONLY; 109 110 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev); 111 if (IS_ERR(bd)) { 112 ret = PTR_ERR(bd); 113 goto out_free_bioset; 114 } 115 ib_dev->ibd_bd = bd; 116 117 q = bdev_get_queue(bd); 118 119 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd); 120 dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q); 121 dev->dev_attrib.hw_queue_depth = q->nr_requests; 122 123 if (target_configure_unmap_from_queue(&dev->dev_attrib, q)) 124 pr_debug("IBLOCK: BLOCK Discard support available," 125 " disabled by default\n"); 126 127 /* 128 * Enable write same emulation for IBLOCK and use 0xFFFF as 129 * the smaller WRITE_SAME(10) only has a two-byte block count. 130 */ 131 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd); 132 if (max_write_zeroes_sectors) 133 dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors; 134 else 135 dev->dev_attrib.max_write_same_len = 0xFFFF; 136 137 if (blk_queue_nonrot(q)) 138 dev->dev_attrib.is_nonrot = 1; 139 140 bi = bdev_get_integrity(bd); 141 if (bi) { 142 struct bio_set *bs = &ib_dev->ibd_bio_set; 143 144 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-IP") || 145 !strcmp(bi->profile->name, "T10-DIF-TYPE1-IP")) { 146 pr_err("IBLOCK export of blk_integrity: %s not" 147 " supported\n", bi->profile->name); 148 ret = -ENOSYS; 149 goto out_blkdev_put; 150 } 151 152 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-CRC")) { 153 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT; 154 } else if (!strcmp(bi->profile->name, "T10-DIF-TYPE1-CRC")) { 155 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT; 156 } 157 158 if (dev->dev_attrib.pi_prot_type) { 159 if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) { 160 pr_err("Unable to allocate bioset for PI\n"); 161 ret = -ENOMEM; 162 goto out_blkdev_put; 163 } 164 pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n", 165 &bs->bio_integrity_pool); 166 } 167 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type; 168 } 169 170 return 0; 171 172 out_blkdev_put: 173 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 174 out_free_bioset: 175 bioset_exit(&ib_dev->ibd_bio_set); 176 out: 177 return ret; 178 } 179 180 static void iblock_dev_call_rcu(struct rcu_head *p) 181 { 182 struct se_device *dev = container_of(p, struct se_device, rcu_head); 183 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 184 185 kfree(ib_dev->ibd_plug); 186 kfree(ib_dev); 187 } 188 189 static void iblock_free_device(struct se_device *dev) 190 { 191 call_rcu(&dev->rcu_head, iblock_dev_call_rcu); 192 } 193 194 static void iblock_destroy_device(struct se_device *dev) 195 { 196 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 197 198 if (ib_dev->ibd_bd != NULL) 199 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 200 bioset_exit(&ib_dev->ibd_bio_set); 201 } 202 203 static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev) 204 { 205 struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev); 206 struct iblock_dev_plug *ib_dev_plug; 207 208 /* 209 * Each se_device has a per cpu work this can be run from. We 210 * shouldn't have multiple threads on the same cpu calling this 211 * at the same time. 212 */ 213 ib_dev_plug = &ib_dev->ibd_plug[raw_smp_processor_id()]; 214 if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags)) 215 return NULL; 216 217 blk_start_plug(&ib_dev_plug->blk_plug); 218 return &ib_dev_plug->se_plug; 219 } 220 221 static void iblock_unplug_device(struct se_dev_plug *se_plug) 222 { 223 struct iblock_dev_plug *ib_dev_plug = container_of(se_plug, 224 struct iblock_dev_plug, se_plug); 225 226 blk_finish_plug(&ib_dev_plug->blk_plug); 227 clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags); 228 } 229 230 static unsigned long long iblock_emulate_read_cap_with_block_size( 231 struct se_device *dev, 232 struct block_device *bd, 233 struct request_queue *q) 234 { 235 u32 block_size = bdev_logical_block_size(bd); 236 unsigned long long blocks_long = 237 div_u64(bdev_nr_bytes(bd), block_size) - 1; 238 239 if (block_size == dev->dev_attrib.block_size) 240 return blocks_long; 241 242 switch (block_size) { 243 case 4096: 244 switch (dev->dev_attrib.block_size) { 245 case 2048: 246 blocks_long <<= 1; 247 break; 248 case 1024: 249 blocks_long <<= 2; 250 break; 251 case 512: 252 blocks_long <<= 3; 253 break; 254 default: 255 break; 256 } 257 break; 258 case 2048: 259 switch (dev->dev_attrib.block_size) { 260 case 4096: 261 blocks_long >>= 1; 262 break; 263 case 1024: 264 blocks_long <<= 1; 265 break; 266 case 512: 267 blocks_long <<= 2; 268 break; 269 default: 270 break; 271 } 272 break; 273 case 1024: 274 switch (dev->dev_attrib.block_size) { 275 case 4096: 276 blocks_long >>= 2; 277 break; 278 case 2048: 279 blocks_long >>= 1; 280 break; 281 case 512: 282 blocks_long <<= 1; 283 break; 284 default: 285 break; 286 } 287 break; 288 case 512: 289 switch (dev->dev_attrib.block_size) { 290 case 4096: 291 blocks_long >>= 3; 292 break; 293 case 2048: 294 blocks_long >>= 2; 295 break; 296 case 1024: 297 blocks_long >>= 1; 298 break; 299 default: 300 break; 301 } 302 break; 303 default: 304 break; 305 } 306 307 return blocks_long; 308 } 309 310 static void iblock_complete_cmd(struct se_cmd *cmd) 311 { 312 struct iblock_req *ibr = cmd->priv; 313 u8 status; 314 315 if (!refcount_dec_and_test(&ibr->pending)) 316 return; 317 318 if (atomic_read(&ibr->ib_bio_err_cnt)) 319 status = SAM_STAT_CHECK_CONDITION; 320 else 321 status = SAM_STAT_GOOD; 322 323 target_complete_cmd(cmd, status); 324 kfree(ibr); 325 } 326 327 static void iblock_bio_done(struct bio *bio) 328 { 329 struct se_cmd *cmd = bio->bi_private; 330 struct iblock_req *ibr = cmd->priv; 331 332 if (bio->bi_status) { 333 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status); 334 /* 335 * Bump the ib_bio_err_cnt and release bio. 336 */ 337 atomic_inc(&ibr->ib_bio_err_cnt); 338 smp_mb__after_atomic(); 339 } 340 341 bio_put(bio); 342 343 iblock_complete_cmd(cmd); 344 } 345 346 static struct bio *iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num, 347 unsigned int opf) 348 { 349 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 350 struct bio *bio; 351 352 /* 353 * Only allocate as many vector entries as the bio code allows us to, 354 * we'll loop later on until we have handled the whole request. 355 */ 356 bio = bio_alloc_bioset(GFP_NOIO, bio_max_segs(sg_num), 357 &ib_dev->ibd_bio_set); 358 if (!bio) { 359 pr_err("Unable to allocate memory for bio\n"); 360 return NULL; 361 } 362 363 bio_set_dev(bio, ib_dev->ibd_bd); 364 bio->bi_private = cmd; 365 bio->bi_end_io = &iblock_bio_done; 366 bio->bi_iter.bi_sector = lba; 367 bio->bi_opf = opf; 368 369 return bio; 370 } 371 372 static void iblock_submit_bios(struct bio_list *list) 373 { 374 struct blk_plug plug; 375 struct bio *bio; 376 /* 377 * The block layer handles nested plugs, so just plug/unplug to handle 378 * fabric drivers that didn't support batching and multi bio cmds. 379 */ 380 blk_start_plug(&plug); 381 while ((bio = bio_list_pop(list))) 382 submit_bio(bio); 383 blk_finish_plug(&plug); 384 } 385 386 static void iblock_end_io_flush(struct bio *bio) 387 { 388 struct se_cmd *cmd = bio->bi_private; 389 390 if (bio->bi_status) 391 pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status); 392 393 if (cmd) { 394 if (bio->bi_status) 395 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION); 396 else 397 target_complete_cmd(cmd, SAM_STAT_GOOD); 398 } 399 400 bio_put(bio); 401 } 402 403 /* 404 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must 405 * always flush the whole cache. 406 */ 407 static sense_reason_t 408 iblock_execute_sync_cache(struct se_cmd *cmd) 409 { 410 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 411 int immed = (cmd->t_task_cdb[1] & 0x2); 412 struct bio *bio; 413 414 /* 415 * If the Immediate bit is set, queue up the GOOD response 416 * for this SYNCHRONIZE_CACHE op. 417 */ 418 if (immed) 419 target_complete_cmd(cmd, SAM_STAT_GOOD); 420 421 bio = bio_alloc(GFP_KERNEL, 0); 422 bio->bi_end_io = iblock_end_io_flush; 423 bio_set_dev(bio, ib_dev->ibd_bd); 424 bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; 425 if (!immed) 426 bio->bi_private = cmd; 427 submit_bio(bio); 428 return 0; 429 } 430 431 static sense_reason_t 432 iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 433 { 434 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 435 struct se_device *dev = cmd->se_dev; 436 int ret; 437 438 ret = blkdev_issue_discard(bdev, 439 target_to_linux_sector(dev, lba), 440 target_to_linux_sector(dev, nolb), 441 GFP_KERNEL, 0); 442 if (ret < 0) { 443 pr_err("blkdev_issue_discard() failed: %d\n", ret); 444 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 445 } 446 447 return 0; 448 } 449 450 static sense_reason_t 451 iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd) 452 { 453 struct se_device *dev = cmd->se_dev; 454 struct scatterlist *sg = &cmd->t_data_sg[0]; 455 unsigned char *buf, *not_zero; 456 int ret; 457 458 buf = kmap(sg_page(sg)) + sg->offset; 459 if (!buf) 460 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 461 /* 462 * Fall back to block_execute_write_same() slow-path if 463 * incoming WRITE_SAME payload does not contain zeros. 464 */ 465 not_zero = memchr_inv(buf, 0x00, cmd->data_length); 466 kunmap(sg_page(sg)); 467 468 if (not_zero) 469 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 470 471 ret = blkdev_issue_zeroout(bdev, 472 target_to_linux_sector(dev, cmd->t_task_lba), 473 target_to_linux_sector(dev, 474 sbc_get_write_same_sectors(cmd)), 475 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); 476 if (ret) 477 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 478 479 target_complete_cmd(cmd, SAM_STAT_GOOD); 480 return 0; 481 } 482 483 static sense_reason_t 484 iblock_execute_write_same(struct se_cmd *cmd) 485 { 486 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 487 struct iblock_req *ibr; 488 struct scatterlist *sg; 489 struct bio *bio; 490 struct bio_list list; 491 struct se_device *dev = cmd->se_dev; 492 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 493 sector_t sectors = target_to_linux_sector(dev, 494 sbc_get_write_same_sectors(cmd)); 495 496 if (cmd->prot_op) { 497 pr_err("WRITE_SAME: Protection information with IBLOCK" 498 " backends not supported\n"); 499 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 500 } 501 sg = &cmd->t_data_sg[0]; 502 503 if (cmd->t_data_nents > 1 || 504 sg->length != cmd->se_dev->dev_attrib.block_size) { 505 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 506 " block_size: %u\n", cmd->t_data_nents, sg->length, 507 cmd->se_dev->dev_attrib.block_size); 508 return TCM_INVALID_CDB_FIELD; 509 } 510 511 if (bdev_write_zeroes_sectors(bdev)) { 512 if (!iblock_execute_zero_out(bdev, cmd)) 513 return 0; 514 } 515 516 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 517 if (!ibr) 518 goto fail; 519 cmd->priv = ibr; 520 521 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); 522 if (!bio) 523 goto fail_free_ibr; 524 525 bio_list_init(&list); 526 bio_list_add(&list, bio); 527 528 refcount_set(&ibr->pending, 1); 529 530 while (sectors) { 531 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 532 != sg->length) { 533 534 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); 535 if (!bio) 536 goto fail_put_bios; 537 538 refcount_inc(&ibr->pending); 539 bio_list_add(&list, bio); 540 } 541 542 /* Always in 512 byte units for Linux/Block */ 543 block_lba += sg->length >> SECTOR_SHIFT; 544 sectors -= sg->length >> SECTOR_SHIFT; 545 } 546 547 iblock_submit_bios(&list); 548 return 0; 549 550 fail_put_bios: 551 while ((bio = bio_list_pop(&list))) 552 bio_put(bio); 553 fail_free_ibr: 554 kfree(ibr); 555 fail: 556 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 557 } 558 559 enum { 560 Opt_udev_path, Opt_readonly, Opt_force, Opt_err 561 }; 562 563 static match_table_t tokens = { 564 {Opt_udev_path, "udev_path=%s"}, 565 {Opt_readonly, "readonly=%d"}, 566 {Opt_force, "force=%d"}, 567 {Opt_err, NULL} 568 }; 569 570 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev, 571 const char *page, ssize_t count) 572 { 573 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 574 char *orig, *ptr, *arg_p, *opts; 575 substring_t args[MAX_OPT_ARGS]; 576 int ret = 0, token; 577 unsigned long tmp_readonly; 578 579 opts = kstrdup(page, GFP_KERNEL); 580 if (!opts) 581 return -ENOMEM; 582 583 orig = opts; 584 585 while ((ptr = strsep(&opts, ",\n")) != NULL) { 586 if (!*ptr) 587 continue; 588 589 token = match_token(ptr, tokens, args); 590 switch (token) { 591 case Opt_udev_path: 592 if (ib_dev->ibd_bd) { 593 pr_err("Unable to set udev_path= while" 594 " ib_dev->ibd_bd exists\n"); 595 ret = -EEXIST; 596 goto out; 597 } 598 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0], 599 SE_UDEV_PATH_LEN) == 0) { 600 ret = -EINVAL; 601 break; 602 } 603 pr_debug("IBLOCK: Referencing UDEV path: %s\n", 604 ib_dev->ibd_udev_path); 605 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 606 break; 607 case Opt_readonly: 608 arg_p = match_strdup(&args[0]); 609 if (!arg_p) { 610 ret = -ENOMEM; 611 break; 612 } 613 ret = kstrtoul(arg_p, 0, &tmp_readonly); 614 kfree(arg_p); 615 if (ret < 0) { 616 pr_err("kstrtoul() failed for" 617 " readonly=\n"); 618 goto out; 619 } 620 ib_dev->ibd_readonly = tmp_readonly; 621 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly); 622 break; 623 case Opt_force: 624 break; 625 default: 626 break; 627 } 628 } 629 630 out: 631 kfree(orig); 632 return (!ret) ? count : ret; 633 } 634 635 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b) 636 { 637 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 638 struct block_device *bd = ib_dev->ibd_bd; 639 ssize_t bl = 0; 640 641 if (bd) 642 bl += sprintf(b + bl, "iBlock device: %pg", bd); 643 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH) 644 bl += sprintf(b + bl, " UDEV PATH: %s", 645 ib_dev->ibd_udev_path); 646 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly); 647 648 bl += sprintf(b + bl, " "); 649 if (bd) { 650 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 651 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), 652 "CLAIMED: IBLOCK"); 653 } else { 654 bl += sprintf(b + bl, "Major: 0 Minor: 0\n"); 655 } 656 657 return bl; 658 } 659 660 static int 661 iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio, 662 struct sg_mapping_iter *miter) 663 { 664 struct se_device *dev = cmd->se_dev; 665 struct blk_integrity *bi; 666 struct bio_integrity_payload *bip; 667 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 668 int rc; 669 size_t resid, len; 670 671 bi = bdev_get_integrity(ib_dev->ibd_bd); 672 if (!bi) { 673 pr_err("Unable to locate bio_integrity\n"); 674 return -ENODEV; 675 } 676 677 bip = bio_integrity_alloc(bio, GFP_NOIO, bio_max_segs(cmd->t_prot_nents)); 678 if (IS_ERR(bip)) { 679 pr_err("Unable to allocate bio_integrity_payload\n"); 680 return PTR_ERR(bip); 681 } 682 683 bip->bip_iter.bi_size = bio_integrity_bytes(bi, bio_sectors(bio)); 684 /* virtual start sector must be in integrity interval units */ 685 bip_set_seed(bip, bio->bi_iter.bi_sector >> 686 (bi->interval_exp - SECTOR_SHIFT)); 687 688 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size, 689 (unsigned long long)bip->bip_iter.bi_sector); 690 691 resid = bip->bip_iter.bi_size; 692 while (resid > 0 && sg_miter_next(miter)) { 693 694 len = min_t(size_t, miter->length, resid); 695 rc = bio_integrity_add_page(bio, miter->page, len, 696 offset_in_page(miter->addr)); 697 if (rc != len) { 698 pr_err("bio_integrity_add_page() failed; %d\n", rc); 699 sg_miter_stop(miter); 700 return -ENOMEM; 701 } 702 703 pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n", 704 miter->page, len, offset_in_page(miter->addr)); 705 706 resid -= len; 707 if (len < miter->length) 708 miter->consumed -= miter->length - len; 709 } 710 sg_miter_stop(miter); 711 712 return 0; 713 } 714 715 static sense_reason_t 716 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 717 enum dma_data_direction data_direction) 718 { 719 struct se_device *dev = cmd->se_dev; 720 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 721 struct iblock_req *ibr; 722 struct bio *bio; 723 struct bio_list list; 724 struct scatterlist *sg; 725 u32 sg_num = sgl_nents; 726 unsigned int opf; 727 unsigned bio_cnt; 728 int i, rc; 729 struct sg_mapping_iter prot_miter; 730 unsigned int miter_dir; 731 732 if (data_direction == DMA_TO_DEVICE) { 733 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 734 struct request_queue *q = bdev_get_queue(ib_dev->ibd_bd); 735 /* 736 * Force writethrough using REQ_FUA if a volatile write cache 737 * is not enabled, or if initiator set the Force Unit Access bit. 738 */ 739 opf = REQ_OP_WRITE; 740 miter_dir = SG_MITER_TO_SG; 741 if (test_bit(QUEUE_FLAG_FUA, &q->queue_flags)) { 742 if (cmd->se_cmd_flags & SCF_FUA) 743 opf |= REQ_FUA; 744 else if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) 745 opf |= REQ_FUA; 746 } 747 } else { 748 opf = REQ_OP_READ; 749 miter_dir = SG_MITER_FROM_SG; 750 } 751 752 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 753 if (!ibr) 754 goto fail; 755 cmd->priv = ibr; 756 757 if (!sgl_nents) { 758 refcount_set(&ibr->pending, 1); 759 iblock_complete_cmd(cmd); 760 return 0; 761 } 762 763 bio = iblock_get_bio(cmd, block_lba, sgl_nents, opf); 764 if (!bio) 765 goto fail_free_ibr; 766 767 bio_list_init(&list); 768 bio_list_add(&list, bio); 769 770 refcount_set(&ibr->pending, 2); 771 bio_cnt = 1; 772 773 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) 774 sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents, 775 miter_dir); 776 777 for_each_sg(sgl, sg, sgl_nents, i) { 778 /* 779 * XXX: if the length the device accepts is shorter than the 780 * length of the S/G list entry this will cause and 781 * endless loop. Better hope no driver uses huge pages. 782 */ 783 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 784 != sg->length) { 785 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 786 rc = iblock_alloc_bip(cmd, bio, &prot_miter); 787 if (rc) 788 goto fail_put_bios; 789 } 790 791 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) { 792 iblock_submit_bios(&list); 793 bio_cnt = 0; 794 } 795 796 bio = iblock_get_bio(cmd, block_lba, sg_num, opf); 797 if (!bio) 798 goto fail_put_bios; 799 800 refcount_inc(&ibr->pending); 801 bio_list_add(&list, bio); 802 bio_cnt++; 803 } 804 805 /* Always in 512 byte units for Linux/Block */ 806 block_lba += sg->length >> SECTOR_SHIFT; 807 sg_num--; 808 } 809 810 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 811 rc = iblock_alloc_bip(cmd, bio, &prot_miter); 812 if (rc) 813 goto fail_put_bios; 814 } 815 816 iblock_submit_bios(&list); 817 iblock_complete_cmd(cmd); 818 return 0; 819 820 fail_put_bios: 821 while ((bio = bio_list_pop(&list))) 822 bio_put(bio); 823 fail_free_ibr: 824 kfree(ibr); 825 fail: 826 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 827 } 828 829 static sector_t iblock_get_blocks(struct se_device *dev) 830 { 831 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 832 struct block_device *bd = ib_dev->ibd_bd; 833 struct request_queue *q = bdev_get_queue(bd); 834 835 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 836 } 837 838 static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev) 839 { 840 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 841 struct block_device *bd = ib_dev->ibd_bd; 842 int ret; 843 844 ret = bdev_alignment_offset(bd); 845 if (ret == -1) 846 return 0; 847 848 /* convert offset-bytes to offset-lbas */ 849 return ret / bdev_logical_block_size(bd); 850 } 851 852 static unsigned int iblock_get_lbppbe(struct se_device *dev) 853 { 854 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 855 struct block_device *bd = ib_dev->ibd_bd; 856 unsigned int logs_per_phys = 857 bdev_physical_block_size(bd) / bdev_logical_block_size(bd); 858 859 return ilog2(logs_per_phys); 860 } 861 862 static unsigned int iblock_get_io_min(struct se_device *dev) 863 { 864 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 865 struct block_device *bd = ib_dev->ibd_bd; 866 867 return bdev_io_min(bd); 868 } 869 870 static unsigned int iblock_get_io_opt(struct se_device *dev) 871 { 872 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 873 struct block_device *bd = ib_dev->ibd_bd; 874 875 return bdev_io_opt(bd); 876 } 877 878 static struct sbc_ops iblock_sbc_ops = { 879 .execute_rw = iblock_execute_rw, 880 .execute_sync_cache = iblock_execute_sync_cache, 881 .execute_write_same = iblock_execute_write_same, 882 .execute_unmap = iblock_execute_unmap, 883 }; 884 885 static sense_reason_t 886 iblock_parse_cdb(struct se_cmd *cmd) 887 { 888 return sbc_parse_cdb(cmd, &iblock_sbc_ops); 889 } 890 891 static bool iblock_get_write_cache(struct se_device *dev) 892 { 893 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 894 struct block_device *bd = ib_dev->ibd_bd; 895 struct request_queue *q = bdev_get_queue(bd); 896 897 return test_bit(QUEUE_FLAG_WC, &q->queue_flags); 898 } 899 900 static const struct target_backend_ops iblock_ops = { 901 .name = "iblock", 902 .inquiry_prod = "IBLOCK", 903 .inquiry_rev = IBLOCK_VERSION, 904 .owner = THIS_MODULE, 905 .attach_hba = iblock_attach_hba, 906 .detach_hba = iblock_detach_hba, 907 .alloc_device = iblock_alloc_device, 908 .configure_device = iblock_configure_device, 909 .destroy_device = iblock_destroy_device, 910 .free_device = iblock_free_device, 911 .plug_device = iblock_plug_device, 912 .unplug_device = iblock_unplug_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 .tb_dev_attrib_attrs = sbc_attrib_attrs, 924 }; 925 926 static int __init iblock_module_init(void) 927 { 928 return transport_backend_register(&iblock_ops); 929 } 930 931 static void __exit iblock_module_exit(void) 932 { 933 target_backend_unregister(&iblock_ops); 934 } 935 936 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 937 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 938 MODULE_LICENSE("GPL"); 939 940 module_init(iblock_module_init); 941 module_exit(iblock_module_exit); 942