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/file.h> 24 #include <linux/module.h> 25 #include <linux/scatterlist.h> 26 #include <scsi/scsi_proto.h> 27 #include <asm/unaligned.h> 28 29 #include <target/target_core_base.h> 30 #include <target/target_core_backend.h> 31 32 #include "target_core_iblock.h" 33 34 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */ 35 #define IBLOCK_BIO_POOL_SIZE 128 36 37 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev) 38 { 39 return container_of(dev, struct iblock_dev, dev); 40 } 41 42 43 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 44 { 45 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 46 " Generic Target Core Stack %s\n", hba->hba_id, 47 IBLOCK_VERSION, TARGET_CORE_VERSION); 48 return 0; 49 } 50 51 static void iblock_detach_hba(struct se_hba *hba) 52 { 53 } 54 55 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name) 56 { 57 struct iblock_dev *ib_dev = NULL; 58 59 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 60 if (!ib_dev) { 61 pr_err("Unable to allocate struct iblock_dev\n"); 62 return NULL; 63 } 64 65 ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug), 66 GFP_KERNEL); 67 if (!ib_dev->ibd_plug) 68 goto free_dev; 69 70 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name); 71 72 return &ib_dev->dev; 73 74 free_dev: 75 kfree(ib_dev); 76 return NULL; 77 } 78 79 static int iblock_configure_device(struct se_device *dev) 80 { 81 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 82 struct request_queue *q; 83 struct block_device *bd = NULL; 84 struct blk_integrity *bi; 85 fmode_t mode; 86 unsigned int max_write_zeroes_sectors; 87 int ret; 88 89 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) { 90 pr_err("Missing udev_path= parameters for IBLOCK\n"); 91 return -EINVAL; 92 } 93 94 ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); 95 if (ret) { 96 pr_err("IBLOCK: Unable to create bioset\n"); 97 goto out; 98 } 99 100 pr_debug( "IBLOCK: Claiming struct block_device: %s\n", 101 ib_dev->ibd_udev_path); 102 103 mode = FMODE_READ|FMODE_EXCL; 104 if (!ib_dev->ibd_readonly) 105 mode |= FMODE_WRITE; 106 else 107 dev->dev_flags |= DF_READ_ONLY; 108 109 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev); 110 if (IS_ERR(bd)) { 111 ret = PTR_ERR(bd); 112 goto out_free_bioset; 113 } 114 ib_dev->ibd_bd = bd; 115 116 q = bdev_get_queue(bd); 117 118 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd); 119 dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q); 120 dev->dev_attrib.hw_queue_depth = q->nr_requests; 121 122 if (target_configure_unmap_from_queue(&dev->dev_attrib, q)) 123 pr_debug("IBLOCK: BLOCK Discard support available," 124 " disabled by default\n"); 125 126 /* 127 * Enable write same emulation for IBLOCK and use 0xFFFF as 128 * the smaller WRITE_SAME(10) only has a two-byte block count. 129 */ 130 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd); 131 if (max_write_zeroes_sectors) 132 dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors; 133 else 134 dev->dev_attrib.max_write_same_len = 0xFFFF; 135 136 if (blk_queue_nonrot(q)) 137 dev->dev_attrib.is_nonrot = 1; 138 139 bi = bdev_get_integrity(bd); 140 if (bi) { 141 struct bio_set *bs = &ib_dev->ibd_bio_set; 142 143 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-IP") || 144 !strcmp(bi->profile->name, "T10-DIF-TYPE1-IP")) { 145 pr_err("IBLOCK export of blk_integrity: %s not" 146 " supported\n", bi->profile->name); 147 ret = -ENOSYS; 148 goto out_blkdev_put; 149 } 150 151 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-CRC")) { 152 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT; 153 } else if (!strcmp(bi->profile->name, "T10-DIF-TYPE1-CRC")) { 154 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT; 155 } 156 157 if (dev->dev_attrib.pi_prot_type) { 158 if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) { 159 pr_err("Unable to allocate bioset for PI\n"); 160 ret = -ENOMEM; 161 goto out_blkdev_put; 162 } 163 pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n", 164 &bs->bio_integrity_pool); 165 } 166 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type; 167 } 168 169 return 0; 170 171 out_blkdev_put: 172 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 173 out_free_bioset: 174 bioset_exit(&ib_dev->ibd_bio_set); 175 out: 176 return ret; 177 } 178 179 static void iblock_dev_call_rcu(struct rcu_head *p) 180 { 181 struct se_device *dev = container_of(p, struct se_device, rcu_head); 182 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 183 184 kfree(ib_dev->ibd_plug); 185 kfree(ib_dev); 186 } 187 188 static void iblock_free_device(struct se_device *dev) 189 { 190 call_rcu(&dev->rcu_head, iblock_dev_call_rcu); 191 } 192 193 static void iblock_destroy_device(struct se_device *dev) 194 { 195 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 196 197 if (ib_dev->ibd_bd != NULL) 198 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 199 bioset_exit(&ib_dev->ibd_bio_set); 200 } 201 202 static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev) 203 { 204 struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev); 205 struct iblock_dev_plug *ib_dev_plug; 206 207 /* 208 * Each se_device has a per cpu work this can be run from. We 209 * shouldn't have multiple threads on the same cpu calling this 210 * at the same time. 211 */ 212 ib_dev_plug = &ib_dev->ibd_plug[raw_smp_processor_id()]; 213 if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags)) 214 return NULL; 215 216 blk_start_plug(&ib_dev_plug->blk_plug); 217 return &ib_dev_plug->se_plug; 218 } 219 220 static void iblock_unplug_device(struct se_dev_plug *se_plug) 221 { 222 struct iblock_dev_plug *ib_dev_plug = container_of(se_plug, 223 struct iblock_dev_plug, se_plug); 224 225 blk_finish_plug(&ib_dev_plug->blk_plug); 226 clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags); 227 } 228 229 static unsigned long long iblock_emulate_read_cap_with_block_size( 230 struct se_device *dev, 231 struct block_device *bd, 232 struct request_queue *q) 233 { 234 u32 block_size = bdev_logical_block_size(bd); 235 unsigned long long blocks_long = 236 div_u64(bdev_nr_bytes(bd), block_size) - 1; 237 238 if (block_size == dev->dev_attrib.block_size) 239 return blocks_long; 240 241 switch (block_size) { 242 case 4096: 243 switch (dev->dev_attrib.block_size) { 244 case 2048: 245 blocks_long <<= 1; 246 break; 247 case 1024: 248 blocks_long <<= 2; 249 break; 250 case 512: 251 blocks_long <<= 3; 252 break; 253 default: 254 break; 255 } 256 break; 257 case 2048: 258 switch (dev->dev_attrib.block_size) { 259 case 4096: 260 blocks_long >>= 1; 261 break; 262 case 1024: 263 blocks_long <<= 1; 264 break; 265 case 512: 266 blocks_long <<= 2; 267 break; 268 default: 269 break; 270 } 271 break; 272 case 1024: 273 switch (dev->dev_attrib.block_size) { 274 case 4096: 275 blocks_long >>= 2; 276 break; 277 case 2048: 278 blocks_long >>= 1; 279 break; 280 case 512: 281 blocks_long <<= 1; 282 break; 283 default: 284 break; 285 } 286 break; 287 case 512: 288 switch (dev->dev_attrib.block_size) { 289 case 4096: 290 blocks_long >>= 3; 291 break; 292 case 2048: 293 blocks_long >>= 2; 294 break; 295 case 1024: 296 blocks_long >>= 1; 297 break; 298 default: 299 break; 300 } 301 break; 302 default: 303 break; 304 } 305 306 return blocks_long; 307 } 308 309 static void iblock_complete_cmd(struct se_cmd *cmd) 310 { 311 struct iblock_req *ibr = cmd->priv; 312 u8 status; 313 314 if (!refcount_dec_and_test(&ibr->pending)) 315 return; 316 317 if (atomic_read(&ibr->ib_bio_err_cnt)) 318 status = SAM_STAT_CHECK_CONDITION; 319 else 320 status = SAM_STAT_GOOD; 321 322 target_complete_cmd(cmd, status); 323 kfree(ibr); 324 } 325 326 static void iblock_bio_done(struct bio *bio) 327 { 328 struct se_cmd *cmd = bio->bi_private; 329 struct iblock_req *ibr = cmd->priv; 330 331 if (bio->bi_status) { 332 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status); 333 /* 334 * Bump the ib_bio_err_cnt and release bio. 335 */ 336 atomic_inc(&ibr->ib_bio_err_cnt); 337 smp_mb__after_atomic(); 338 } 339 340 bio_put(bio); 341 342 iblock_complete_cmd(cmd); 343 } 344 345 static struct bio *iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num, 346 unsigned int opf) 347 { 348 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 349 struct bio *bio; 350 351 /* 352 * Only allocate as many vector entries as the bio code allows us to, 353 * we'll loop later on until we have handled the whole request. 354 */ 355 bio = bio_alloc_bioset(ib_dev->ibd_bd, bio_max_segs(sg_num), opf, 356 GFP_NOIO, &ib_dev->ibd_bio_set); 357 if (!bio) { 358 pr_err("Unable to allocate memory for bio\n"); 359 return NULL; 360 } 361 362 bio->bi_private = cmd; 363 bio->bi_end_io = &iblock_bio_done; 364 bio->bi_iter.bi_sector = lba; 365 366 return bio; 367 } 368 369 static void iblock_submit_bios(struct bio_list *list) 370 { 371 struct blk_plug plug; 372 struct bio *bio; 373 /* 374 * The block layer handles nested plugs, so just plug/unplug to handle 375 * fabric drivers that didn't support batching and multi bio cmds. 376 */ 377 blk_start_plug(&plug); 378 while ((bio = bio_list_pop(list))) 379 submit_bio(bio); 380 blk_finish_plug(&plug); 381 } 382 383 static void iblock_end_io_flush(struct bio *bio) 384 { 385 struct se_cmd *cmd = bio->bi_private; 386 387 if (bio->bi_status) 388 pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status); 389 390 if (cmd) { 391 if (bio->bi_status) 392 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION); 393 else 394 target_complete_cmd(cmd, SAM_STAT_GOOD); 395 } 396 397 bio_put(bio); 398 } 399 400 /* 401 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must 402 * always flush the whole cache. 403 */ 404 static sense_reason_t 405 iblock_execute_sync_cache(struct se_cmd *cmd) 406 { 407 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 408 int immed = (cmd->t_task_cdb[1] & 0x2); 409 struct bio *bio; 410 411 /* 412 * If the Immediate bit is set, queue up the GOOD response 413 * for this SYNCHRONIZE_CACHE op. 414 */ 415 if (immed) 416 target_complete_cmd(cmd, SAM_STAT_GOOD); 417 418 bio = bio_alloc(GFP_KERNEL, 0); 419 bio->bi_end_io = iblock_end_io_flush; 420 bio_set_dev(bio, ib_dev->ibd_bd); 421 bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; 422 if (!immed) 423 bio->bi_private = cmd; 424 submit_bio(bio); 425 return 0; 426 } 427 428 static sense_reason_t 429 iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 430 { 431 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 432 struct se_device *dev = cmd->se_dev; 433 int ret; 434 435 ret = blkdev_issue_discard(bdev, 436 target_to_linux_sector(dev, lba), 437 target_to_linux_sector(dev, nolb), 438 GFP_KERNEL, 0); 439 if (ret < 0) { 440 pr_err("blkdev_issue_discard() failed: %d\n", ret); 441 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 442 } 443 444 return 0; 445 } 446 447 static sense_reason_t 448 iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd) 449 { 450 struct se_device *dev = cmd->se_dev; 451 struct scatterlist *sg = &cmd->t_data_sg[0]; 452 unsigned char *buf, *not_zero; 453 int ret; 454 455 buf = kmap(sg_page(sg)) + sg->offset; 456 if (!buf) 457 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 458 /* 459 * Fall back to block_execute_write_same() slow-path if 460 * incoming WRITE_SAME payload does not contain zeros. 461 */ 462 not_zero = memchr_inv(buf, 0x00, cmd->data_length); 463 kunmap(sg_page(sg)); 464 465 if (not_zero) 466 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 467 468 ret = blkdev_issue_zeroout(bdev, 469 target_to_linux_sector(dev, cmd->t_task_lba), 470 target_to_linux_sector(dev, 471 sbc_get_write_same_sectors(cmd)), 472 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); 473 if (ret) 474 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 475 476 target_complete_cmd(cmd, SAM_STAT_GOOD); 477 return 0; 478 } 479 480 static sense_reason_t 481 iblock_execute_write_same(struct se_cmd *cmd) 482 { 483 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 484 struct iblock_req *ibr; 485 struct scatterlist *sg; 486 struct bio *bio; 487 struct bio_list list; 488 struct se_device *dev = cmd->se_dev; 489 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 490 sector_t sectors = target_to_linux_sector(dev, 491 sbc_get_write_same_sectors(cmd)); 492 493 if (cmd->prot_op) { 494 pr_err("WRITE_SAME: Protection information with IBLOCK" 495 " backends not supported\n"); 496 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 497 } 498 sg = &cmd->t_data_sg[0]; 499 500 if (cmd->t_data_nents > 1 || 501 sg->length != cmd->se_dev->dev_attrib.block_size) { 502 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 503 " block_size: %u\n", cmd->t_data_nents, sg->length, 504 cmd->se_dev->dev_attrib.block_size); 505 return TCM_INVALID_CDB_FIELD; 506 } 507 508 if (bdev_write_zeroes_sectors(bdev)) { 509 if (!iblock_execute_zero_out(bdev, cmd)) 510 return 0; 511 } 512 513 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 514 if (!ibr) 515 goto fail; 516 cmd->priv = ibr; 517 518 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); 519 if (!bio) 520 goto fail_free_ibr; 521 522 bio_list_init(&list); 523 bio_list_add(&list, bio); 524 525 refcount_set(&ibr->pending, 1); 526 527 while (sectors) { 528 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 529 != sg->length) { 530 531 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); 532 if (!bio) 533 goto fail_put_bios; 534 535 refcount_inc(&ibr->pending); 536 bio_list_add(&list, bio); 537 } 538 539 /* Always in 512 byte units for Linux/Block */ 540 block_lba += sg->length >> SECTOR_SHIFT; 541 sectors -= sg->length >> SECTOR_SHIFT; 542 } 543 544 iblock_submit_bios(&list); 545 return 0; 546 547 fail_put_bios: 548 while ((bio = bio_list_pop(&list))) 549 bio_put(bio); 550 fail_free_ibr: 551 kfree(ibr); 552 fail: 553 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 554 } 555 556 enum { 557 Opt_udev_path, Opt_readonly, Opt_force, Opt_err 558 }; 559 560 static match_table_t tokens = { 561 {Opt_udev_path, "udev_path=%s"}, 562 {Opt_readonly, "readonly=%d"}, 563 {Opt_force, "force=%d"}, 564 {Opt_err, NULL} 565 }; 566 567 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev, 568 const char *page, ssize_t count) 569 { 570 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 571 char *orig, *ptr, *arg_p, *opts; 572 substring_t args[MAX_OPT_ARGS]; 573 int ret = 0, token; 574 unsigned long tmp_readonly; 575 576 opts = kstrdup(page, GFP_KERNEL); 577 if (!opts) 578 return -ENOMEM; 579 580 orig = opts; 581 582 while ((ptr = strsep(&opts, ",\n")) != NULL) { 583 if (!*ptr) 584 continue; 585 586 token = match_token(ptr, tokens, args); 587 switch (token) { 588 case Opt_udev_path: 589 if (ib_dev->ibd_bd) { 590 pr_err("Unable to set udev_path= while" 591 " ib_dev->ibd_bd exists\n"); 592 ret = -EEXIST; 593 goto out; 594 } 595 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0], 596 SE_UDEV_PATH_LEN) == 0) { 597 ret = -EINVAL; 598 break; 599 } 600 pr_debug("IBLOCK: Referencing UDEV path: %s\n", 601 ib_dev->ibd_udev_path); 602 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 603 break; 604 case Opt_readonly: 605 arg_p = match_strdup(&args[0]); 606 if (!arg_p) { 607 ret = -ENOMEM; 608 break; 609 } 610 ret = kstrtoul(arg_p, 0, &tmp_readonly); 611 kfree(arg_p); 612 if (ret < 0) { 613 pr_err("kstrtoul() failed for" 614 " readonly=\n"); 615 goto out; 616 } 617 ib_dev->ibd_readonly = tmp_readonly; 618 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly); 619 break; 620 case Opt_force: 621 break; 622 default: 623 break; 624 } 625 } 626 627 out: 628 kfree(orig); 629 return (!ret) ? count : ret; 630 } 631 632 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b) 633 { 634 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 635 struct block_device *bd = ib_dev->ibd_bd; 636 ssize_t bl = 0; 637 638 if (bd) 639 bl += sprintf(b + bl, "iBlock device: %pg", bd); 640 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH) 641 bl += sprintf(b + bl, " UDEV PATH: %s", 642 ib_dev->ibd_udev_path); 643 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly); 644 645 bl += sprintf(b + bl, " "); 646 if (bd) { 647 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 648 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), 649 "CLAIMED: IBLOCK"); 650 } else { 651 bl += sprintf(b + bl, "Major: 0 Minor: 0\n"); 652 } 653 654 return bl; 655 } 656 657 static int 658 iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio, 659 struct sg_mapping_iter *miter) 660 { 661 struct se_device *dev = cmd->se_dev; 662 struct blk_integrity *bi; 663 struct bio_integrity_payload *bip; 664 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 665 int rc; 666 size_t resid, len; 667 668 bi = bdev_get_integrity(ib_dev->ibd_bd); 669 if (!bi) { 670 pr_err("Unable to locate bio_integrity\n"); 671 return -ENODEV; 672 } 673 674 bip = bio_integrity_alloc(bio, GFP_NOIO, bio_max_segs(cmd->t_prot_nents)); 675 if (IS_ERR(bip)) { 676 pr_err("Unable to allocate bio_integrity_payload\n"); 677 return PTR_ERR(bip); 678 } 679 680 bip->bip_iter.bi_size = bio_integrity_bytes(bi, bio_sectors(bio)); 681 /* virtual start sector must be in integrity interval units */ 682 bip_set_seed(bip, bio->bi_iter.bi_sector >> 683 (bi->interval_exp - SECTOR_SHIFT)); 684 685 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size, 686 (unsigned long long)bip->bip_iter.bi_sector); 687 688 resid = bip->bip_iter.bi_size; 689 while (resid > 0 && sg_miter_next(miter)) { 690 691 len = min_t(size_t, miter->length, resid); 692 rc = bio_integrity_add_page(bio, miter->page, len, 693 offset_in_page(miter->addr)); 694 if (rc != len) { 695 pr_err("bio_integrity_add_page() failed; %d\n", rc); 696 sg_miter_stop(miter); 697 return -ENOMEM; 698 } 699 700 pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n", 701 miter->page, len, offset_in_page(miter->addr)); 702 703 resid -= len; 704 if (len < miter->length) 705 miter->consumed -= miter->length - len; 706 } 707 sg_miter_stop(miter); 708 709 return 0; 710 } 711 712 static sense_reason_t 713 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 714 enum dma_data_direction data_direction) 715 { 716 struct se_device *dev = cmd->se_dev; 717 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 718 struct iblock_req *ibr; 719 struct bio *bio; 720 struct bio_list list; 721 struct scatterlist *sg; 722 u32 sg_num = sgl_nents; 723 unsigned int opf; 724 unsigned bio_cnt; 725 int i, rc; 726 struct sg_mapping_iter prot_miter; 727 unsigned int miter_dir; 728 729 if (data_direction == DMA_TO_DEVICE) { 730 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 731 struct request_queue *q = bdev_get_queue(ib_dev->ibd_bd); 732 /* 733 * Force writethrough using REQ_FUA if a volatile write cache 734 * is not enabled, or if initiator set the Force Unit Access bit. 735 */ 736 opf = REQ_OP_WRITE; 737 miter_dir = SG_MITER_TO_SG; 738 if (test_bit(QUEUE_FLAG_FUA, &q->queue_flags)) { 739 if (cmd->se_cmd_flags & SCF_FUA) 740 opf |= REQ_FUA; 741 else if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) 742 opf |= REQ_FUA; 743 } 744 } else { 745 opf = REQ_OP_READ; 746 miter_dir = SG_MITER_FROM_SG; 747 } 748 749 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 750 if (!ibr) 751 goto fail; 752 cmd->priv = ibr; 753 754 if (!sgl_nents) { 755 refcount_set(&ibr->pending, 1); 756 iblock_complete_cmd(cmd); 757 return 0; 758 } 759 760 bio = iblock_get_bio(cmd, block_lba, sgl_nents, opf); 761 if (!bio) 762 goto fail_free_ibr; 763 764 bio_list_init(&list); 765 bio_list_add(&list, bio); 766 767 refcount_set(&ibr->pending, 2); 768 bio_cnt = 1; 769 770 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) 771 sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents, 772 miter_dir); 773 774 for_each_sg(sgl, sg, sgl_nents, i) { 775 /* 776 * XXX: if the length the device accepts is shorter than the 777 * length of the S/G list entry this will cause and 778 * endless loop. Better hope no driver uses huge pages. 779 */ 780 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 781 != sg->length) { 782 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 783 rc = iblock_alloc_bip(cmd, bio, &prot_miter); 784 if (rc) 785 goto fail_put_bios; 786 } 787 788 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) { 789 iblock_submit_bios(&list); 790 bio_cnt = 0; 791 } 792 793 bio = iblock_get_bio(cmd, block_lba, sg_num, opf); 794 if (!bio) 795 goto fail_put_bios; 796 797 refcount_inc(&ibr->pending); 798 bio_list_add(&list, bio); 799 bio_cnt++; 800 } 801 802 /* Always in 512 byte units for Linux/Block */ 803 block_lba += sg->length >> SECTOR_SHIFT; 804 sg_num--; 805 } 806 807 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 808 rc = iblock_alloc_bip(cmd, bio, &prot_miter); 809 if (rc) 810 goto fail_put_bios; 811 } 812 813 iblock_submit_bios(&list); 814 iblock_complete_cmd(cmd); 815 return 0; 816 817 fail_put_bios: 818 while ((bio = bio_list_pop(&list))) 819 bio_put(bio); 820 fail_free_ibr: 821 kfree(ibr); 822 fail: 823 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 824 } 825 826 static sector_t iblock_get_blocks(struct se_device *dev) 827 { 828 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 829 struct block_device *bd = ib_dev->ibd_bd; 830 struct request_queue *q = bdev_get_queue(bd); 831 832 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 833 } 834 835 static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev) 836 { 837 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 838 struct block_device *bd = ib_dev->ibd_bd; 839 int ret; 840 841 ret = bdev_alignment_offset(bd); 842 if (ret == -1) 843 return 0; 844 845 /* convert offset-bytes to offset-lbas */ 846 return ret / bdev_logical_block_size(bd); 847 } 848 849 static unsigned int iblock_get_lbppbe(struct se_device *dev) 850 { 851 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 852 struct block_device *bd = ib_dev->ibd_bd; 853 unsigned int logs_per_phys = 854 bdev_physical_block_size(bd) / bdev_logical_block_size(bd); 855 856 return ilog2(logs_per_phys); 857 } 858 859 static unsigned int iblock_get_io_min(struct se_device *dev) 860 { 861 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 862 struct block_device *bd = ib_dev->ibd_bd; 863 864 return bdev_io_min(bd); 865 } 866 867 static unsigned int iblock_get_io_opt(struct se_device *dev) 868 { 869 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 870 struct block_device *bd = ib_dev->ibd_bd; 871 872 return bdev_io_opt(bd); 873 } 874 875 static struct sbc_ops iblock_sbc_ops = { 876 .execute_rw = iblock_execute_rw, 877 .execute_sync_cache = iblock_execute_sync_cache, 878 .execute_write_same = iblock_execute_write_same, 879 .execute_unmap = iblock_execute_unmap, 880 }; 881 882 static sense_reason_t 883 iblock_parse_cdb(struct se_cmd *cmd) 884 { 885 return sbc_parse_cdb(cmd, &iblock_sbc_ops); 886 } 887 888 static bool iblock_get_write_cache(struct se_device *dev) 889 { 890 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 891 struct block_device *bd = ib_dev->ibd_bd; 892 struct request_queue *q = bdev_get_queue(bd); 893 894 return test_bit(QUEUE_FLAG_WC, &q->queue_flags); 895 } 896 897 static const struct target_backend_ops iblock_ops = { 898 .name = "iblock", 899 .inquiry_prod = "IBLOCK", 900 .inquiry_rev = IBLOCK_VERSION, 901 .owner = THIS_MODULE, 902 .attach_hba = iblock_attach_hba, 903 .detach_hba = iblock_detach_hba, 904 .alloc_device = iblock_alloc_device, 905 .configure_device = iblock_configure_device, 906 .destroy_device = iblock_destroy_device, 907 .free_device = iblock_free_device, 908 .plug_device = iblock_plug_device, 909 .unplug_device = iblock_unplug_device, 910 .parse_cdb = iblock_parse_cdb, 911 .set_configfs_dev_params = iblock_set_configfs_dev_params, 912 .show_configfs_dev_params = iblock_show_configfs_dev_params, 913 .get_device_type = sbc_get_device_type, 914 .get_blocks = iblock_get_blocks, 915 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas, 916 .get_lbppbe = iblock_get_lbppbe, 917 .get_io_min = iblock_get_io_min, 918 .get_io_opt = iblock_get_io_opt, 919 .get_write_cache = iblock_get_write_cache, 920 .tb_dev_attrib_attrs = sbc_attrib_attrs, 921 }; 922 923 static int __init iblock_module_init(void) 924 { 925 return transport_backend_register(&iblock_ops); 926 } 927 928 static void __exit iblock_module_exit(void) 929 { 930 target_backend_unregister(&iblock_ops); 931 } 932 933 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 934 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 935 MODULE_LICENSE("GPL"); 936 937 module_init(iblock_module_init); 938 module_exit(iblock_module_exit); 939