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