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 <linux/pr.h> 27 #include <scsi/scsi_proto.h> 28 #include <scsi/scsi_common.h> 29 #include <linux/unaligned.h> 30 31 #include <target/target_core_base.h> 32 #include <target/target_core_backend.h> 33 34 #include "target_core_iblock.h" 35 #include "target_core_pr.h" 36 37 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */ 38 #define IBLOCK_BIO_POOL_SIZE 128 39 40 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev) 41 { 42 return container_of(dev, struct iblock_dev, dev); 43 } 44 45 46 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 47 { 48 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 49 " Generic Target Core Stack %s\n", hba->hba_id, 50 IBLOCK_VERSION, TARGET_CORE_VERSION); 51 return 0; 52 } 53 54 static void iblock_detach_hba(struct se_hba *hba) 55 { 56 } 57 58 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name) 59 { 60 struct iblock_dev *ib_dev = NULL; 61 62 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 63 if (!ib_dev) { 64 pr_err("Unable to allocate struct iblock_dev\n"); 65 return NULL; 66 } 67 68 ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug), 69 GFP_KERNEL); 70 if (!ib_dev->ibd_plug) 71 goto free_dev; 72 73 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name); 74 75 return &ib_dev->dev; 76 77 free_dev: 78 kfree(ib_dev); 79 return NULL; 80 } 81 82 static bool iblock_configure_unmap(struct se_device *dev) 83 { 84 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 85 86 return target_configure_unmap_from_queue(&dev->dev_attrib, 87 ib_dev->ibd_bd); 88 } 89 90 static int iblock_configure_device(struct se_device *dev) 91 { 92 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 93 struct request_queue *q; 94 struct file *bdev_file; 95 struct block_device *bd; 96 struct blk_integrity *bi; 97 blk_mode_t mode = BLK_OPEN_READ; 98 unsigned int max_write_zeroes_sectors; 99 int ret; 100 101 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) { 102 pr_err("Missing udev_path= parameters for IBLOCK\n"); 103 return -EINVAL; 104 } 105 106 ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); 107 if (ret) { 108 pr_err("IBLOCK: Unable to create bioset\n"); 109 goto out; 110 } 111 112 pr_debug( "IBLOCK: Claiming struct block_device: %s\n", 113 ib_dev->ibd_udev_path); 114 115 if (!ib_dev->ibd_readonly) 116 mode |= BLK_OPEN_WRITE; 117 else 118 dev->dev_flags |= DF_READ_ONLY; 119 120 bdev_file = bdev_file_open_by_path(ib_dev->ibd_udev_path, mode, ib_dev, 121 NULL); 122 if (IS_ERR(bdev_file)) { 123 ret = PTR_ERR(bdev_file); 124 goto out_free_bioset; 125 } 126 ib_dev->ibd_bdev_file = bdev_file; 127 ib_dev->ibd_bd = bd = file_bdev(bdev_file); 128 129 q = bdev_get_queue(bd); 130 131 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd); 132 dev->dev_attrib.hw_max_sectors = mult_frac(queue_max_hw_sectors(q), 133 SECTOR_SIZE, 134 dev->dev_attrib.hw_block_size); 135 dev->dev_attrib.hw_queue_depth = q->nr_requests; 136 137 /* 138 * Enable write same emulation for IBLOCK and use 0xFFFF as 139 * the smaller WRITE_SAME(10) only has a two-byte block count. 140 */ 141 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd); 142 if (max_write_zeroes_sectors) 143 dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors; 144 else 145 dev->dev_attrib.max_write_same_len = 0xFFFF; 146 147 if (bdev_nonrot(bd)) 148 dev->dev_attrib.is_nonrot = 1; 149 150 bi = bdev_get_integrity(bd); 151 if (!bi) 152 return 0; 153 154 switch (bi->csum_type) { 155 case BLK_INTEGRITY_CSUM_IP: 156 pr_err("IBLOCK export of blk_integrity: %s not supported\n", 157 blk_integrity_profile_name(bi)); 158 ret = -ENOSYS; 159 goto out_blkdev_put; 160 case BLK_INTEGRITY_CSUM_CRC: 161 if (bi->flags & BLK_INTEGRITY_REF_TAG) 162 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT; 163 else 164 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT; 165 break; 166 default: 167 break; 168 } 169 170 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type; 171 return 0; 172 173 out_blkdev_put: 174 fput(ib_dev->ibd_bdev_file); 175 out_free_bioset: 176 bioset_exit(&ib_dev->ibd_bio_set); 177 out: 178 return ret; 179 } 180 181 static void iblock_dev_call_rcu(struct rcu_head *p) 182 { 183 struct se_device *dev = container_of(p, struct se_device, rcu_head); 184 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 185 186 kfree(ib_dev->ibd_plug); 187 kfree(ib_dev); 188 } 189 190 static void iblock_free_device(struct se_device *dev) 191 { 192 call_rcu(&dev->rcu_head, iblock_dev_call_rcu); 193 } 194 195 static void iblock_destroy_device(struct se_device *dev) 196 { 197 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 198 199 if (ib_dev->ibd_bdev_file) 200 fput(ib_dev->ibd_bdev_file); 201 bioset_exit(&ib_dev->ibd_bio_set); 202 } 203 204 static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev) 205 { 206 struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev); 207 struct iblock_dev_plug *ib_dev_plug; 208 209 /* 210 * Each se_device has a per cpu work this can be run from. We 211 * shouldn't have multiple threads on the same cpu calling this 212 * at the same time. 213 */ 214 ib_dev_plug = &ib_dev->ibd_plug[raw_smp_processor_id()]; 215 if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags)) 216 return NULL; 217 218 blk_start_plug(&ib_dev_plug->blk_plug); 219 return &ib_dev_plug->se_plug; 220 } 221 222 static void iblock_unplug_device(struct se_dev_plug *se_plug) 223 { 224 struct iblock_dev_plug *ib_dev_plug = container_of(se_plug, 225 struct iblock_dev_plug, se_plug); 226 227 blk_finish_plug(&ib_dev_plug->blk_plug); 228 clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags); 229 } 230 231 static sector_t iblock_get_blocks(struct se_device *dev) 232 { 233 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 234 u32 block_size = bdev_logical_block_size(ib_dev->ibd_bd); 235 unsigned long long blocks_long = 236 div_u64(bdev_nr_bytes(ib_dev->ibd_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, blk_status_t blk_status) 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 (blk_status == BLK_STS_RESV_CONFLICT) 318 status = SAM_STAT_RESERVATION_CONFLICT; 319 else if (atomic_read(&ibr->ib_bio_err_cnt)) 320 status = SAM_STAT_CHECK_CONDITION; 321 else 322 status = SAM_STAT_GOOD; 323 324 target_complete_cmd(cmd, status); 325 kfree(ibr); 326 } 327 328 static void iblock_bio_done(struct bio *bio) 329 { 330 struct se_cmd *cmd = bio->bi_private; 331 struct iblock_req *ibr = cmd->priv; 332 blk_status_t blk_status = bio->bi_status; 333 334 if (bio->bi_status) { 335 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status); 336 /* 337 * Bump the ib_bio_err_cnt and release bio. 338 */ 339 atomic_inc(&ibr->ib_bio_err_cnt); 340 smp_mb__after_atomic(); 341 } 342 343 bio_put(bio); 344 345 iblock_complete_cmd(cmd, blk_status); 346 } 347 348 static struct bio *iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num, 349 blk_opf_t opf) 350 { 351 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 352 struct bio *bio; 353 354 /* 355 * Only allocate as many vector entries as the bio code allows us to, 356 * we'll loop later on until we have handled the whole request. 357 */ 358 bio = bio_alloc_bioset(ib_dev->ibd_bd, bio_max_segs(sg_num), opf, 359 GFP_NOIO, &ib_dev->ibd_bio_set); 360 if (!bio) { 361 pr_err("Unable to allocate memory for bio\n"); 362 return NULL; 363 } 364 365 bio->bi_private = cmd; 366 bio->bi_end_io = &iblock_bio_done; 367 bio->bi_iter.bi_sector = lba; 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(ib_dev->ibd_bd, 0, REQ_OP_WRITE | REQ_PREFLUSH, 422 GFP_KERNEL); 423 bio->bi_end_io = iblock_end_io_flush; 424 if (!immed) 425 bio->bi_private = cmd; 426 submit_bio(bio); 427 return 0; 428 } 429 430 static sense_reason_t 431 iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 432 { 433 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 434 struct se_device *dev = cmd->se_dev; 435 int ret; 436 437 ret = blkdev_issue_discard(bdev, 438 target_to_linux_sector(dev, lba), 439 target_to_linux_sector(dev, nolb), 440 GFP_KERNEL); 441 if (ret < 0) { 442 pr_err("blkdev_issue_discard() failed: %d\n", ret); 443 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 444 } 445 446 return 0; 447 } 448 449 static sense_reason_t 450 iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd) 451 { 452 struct se_device *dev = cmd->se_dev; 453 struct scatterlist *sg = &cmd->t_data_sg[0]; 454 unsigned char *buf, *not_zero; 455 int ret; 456 457 buf = kmap(sg_page(sg)) + sg->offset; 458 if (!buf) 459 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 460 /* 461 * Fall back to block_execute_write_same() slow-path if 462 * incoming WRITE_SAME payload does not contain zeros. 463 */ 464 not_zero = memchr_inv(buf, 0x00, cmd->data_length); 465 kunmap(sg_page(sg)); 466 467 if (not_zero) 468 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 469 470 ret = blkdev_issue_zeroout(bdev, 471 target_to_linux_sector(dev, cmd->t_task_lba), 472 target_to_linux_sector(dev, 473 sbc_get_write_same_sectors(cmd)), 474 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); 475 if (ret) 476 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 477 478 target_complete_cmd(cmd, SAM_STAT_GOOD); 479 return 0; 480 } 481 482 static sense_reason_t 483 iblock_execute_write_same(struct se_cmd *cmd) 484 { 485 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 486 struct iblock_req *ibr; 487 struct scatterlist *sg; 488 struct bio *bio; 489 struct bio_list list; 490 struct se_device *dev = cmd->se_dev; 491 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 492 sector_t sectors = target_to_linux_sector(dev, 493 sbc_get_write_same_sectors(cmd)); 494 495 if (cmd->prot_op) { 496 pr_err("WRITE_SAME: Protection information with IBLOCK" 497 " backends not supported\n"); 498 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 499 } 500 501 if (!cmd->t_data_nents) 502 return TCM_INVALID_CDB_FIELD; 503 504 sg = &cmd->t_data_sg[0]; 505 506 if (cmd->t_data_nents > 1 || 507 sg->length != cmd->se_dev->dev_attrib.block_size) { 508 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 509 " block_size: %u\n", cmd->t_data_nents, sg->length, 510 cmd->se_dev->dev_attrib.block_size); 511 return TCM_INVALID_CDB_FIELD; 512 } 513 514 if (bdev_write_zeroes_sectors(bdev)) { 515 if (!iblock_execute_zero_out(bdev, cmd)) 516 return 0; 517 } 518 519 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 520 if (!ibr) 521 goto fail; 522 cmd->priv = ibr; 523 524 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); 525 if (!bio) 526 goto fail_free_ibr; 527 528 bio_list_init(&list); 529 bio_list_add(&list, bio); 530 531 refcount_set(&ibr->pending, 1); 532 533 while (sectors) { 534 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 535 != sg->length) { 536 537 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); 538 if (!bio) 539 goto fail_put_bios; 540 541 refcount_inc(&ibr->pending); 542 bio_list_add(&list, bio); 543 } 544 545 /* Always in 512 byte units for Linux/Block */ 546 block_lba += sg->length >> SECTOR_SHIFT; 547 sectors -= sg->length >> SECTOR_SHIFT; 548 } 549 550 iblock_submit_bios(&list); 551 return 0; 552 553 fail_put_bios: 554 while ((bio = bio_list_pop(&list))) 555 bio_put(bio); 556 fail_free_ibr: 557 kfree(ibr); 558 fail: 559 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 560 } 561 562 enum { 563 Opt_udev_path, Opt_readonly, Opt_force, Opt_err 564 }; 565 566 static match_table_t tokens = { 567 {Opt_udev_path, "udev_path=%s"}, 568 {Opt_readonly, "readonly=%d"}, 569 {Opt_force, "force=%d"}, 570 {Opt_err, NULL} 571 }; 572 573 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev, 574 const char *page, ssize_t count) 575 { 576 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 577 char *orig, *ptr, *arg_p, *opts; 578 substring_t args[MAX_OPT_ARGS]; 579 int ret = 0, token; 580 unsigned long tmp_readonly; 581 582 opts = kstrdup(page, GFP_KERNEL); 583 if (!opts) 584 return -ENOMEM; 585 586 orig = opts; 587 588 while ((ptr = strsep(&opts, ",\n")) != NULL) { 589 if (!*ptr) 590 continue; 591 592 token = match_token(ptr, tokens, args); 593 switch (token) { 594 case Opt_udev_path: 595 if (ib_dev->ibd_bd) { 596 pr_err("Unable to set udev_path= while" 597 " ib_dev->ibd_bd exists\n"); 598 ret = -EEXIST; 599 goto out; 600 } 601 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0], 602 SE_UDEV_PATH_LEN) == 0) { 603 ret = -EINVAL; 604 break; 605 } 606 pr_debug("IBLOCK: Referencing UDEV path: %s\n", 607 ib_dev->ibd_udev_path); 608 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 609 break; 610 case Opt_readonly: 611 arg_p = match_strdup(&args[0]); 612 if (!arg_p) { 613 ret = -ENOMEM; 614 break; 615 } 616 ret = kstrtoul(arg_p, 0, &tmp_readonly); 617 kfree(arg_p); 618 if (ret < 0) { 619 pr_err("kstrtoul() failed for" 620 " readonly=\n"); 621 goto out; 622 } 623 ib_dev->ibd_readonly = tmp_readonly; 624 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly); 625 break; 626 case Opt_force: 627 break; 628 default: 629 break; 630 } 631 } 632 633 out: 634 kfree(orig); 635 return (!ret) ? count : ret; 636 } 637 638 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b) 639 { 640 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 641 struct block_device *bd = ib_dev->ibd_bd; 642 ssize_t bl = 0; 643 644 if (bd) 645 bl += sprintf(b + bl, "iBlock device: %pg", bd); 646 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH) 647 bl += sprintf(b + bl, " UDEV PATH: %s", 648 ib_dev->ibd_udev_path); 649 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly); 650 651 bl += sprintf(b + bl, " "); 652 if (bd) { 653 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 654 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), 655 "CLAIMED: IBLOCK"); 656 } else { 657 bl += sprintf(b + bl, "Major: 0 Minor: 0\n"); 658 } 659 660 return bl; 661 } 662 663 static int 664 iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio, 665 struct sg_mapping_iter *miter) 666 { 667 struct se_device *dev = cmd->se_dev; 668 struct blk_integrity *bi; 669 struct bio_integrity_payload *bip; 670 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 671 int rc; 672 size_t resid, len; 673 674 bi = bdev_get_integrity(ib_dev->ibd_bd); 675 if (!bi) { 676 pr_err("Unable to locate bio_integrity\n"); 677 return -ENODEV; 678 } 679 680 bip = bio_integrity_alloc(bio, GFP_NOIO, bio_max_segs(cmd->t_prot_nents)); 681 if (IS_ERR(bip)) { 682 pr_err("Unable to allocate bio_integrity_payload\n"); 683 return PTR_ERR(bip); 684 } 685 686 /* virtual start sector must be in integrity interval units */ 687 bip_set_seed(bip, bio->bi_iter.bi_sector >> 688 (bi->interval_exp - SECTOR_SHIFT)); 689 690 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size, 691 (unsigned long long)bip->bip_iter.bi_sector); 692 693 resid = bio_integrity_bytes(bi, bio_sectors(bio)); 694 while (resid > 0 && sg_miter_next(miter)) { 695 696 len = min_t(size_t, miter->length, resid); 697 rc = bio_integrity_add_page(bio, miter->page, len, 698 offset_in_page(miter->addr)); 699 if (rc != len) { 700 pr_err("bio_integrity_add_page() failed; %d\n", rc); 701 sg_miter_stop(miter); 702 return -ENOMEM; 703 } 704 705 pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n", 706 miter->page, len, offset_in_page(miter->addr)); 707 708 resid -= len; 709 if (len < miter->length) 710 miter->consumed -= miter->length - len; 711 } 712 sg_miter_stop(miter); 713 714 return 0; 715 } 716 717 static sense_reason_t 718 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 719 enum dma_data_direction data_direction) 720 { 721 struct se_device *dev = cmd->se_dev; 722 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 723 struct iblock_req *ibr; 724 struct bio *bio; 725 struct bio_list list; 726 struct scatterlist *sg; 727 u32 sg_num = sgl_nents; 728 blk_opf_t opf; 729 unsigned bio_cnt; 730 int i, rc; 731 struct sg_mapping_iter prot_miter; 732 unsigned int miter_dir; 733 734 if (data_direction == DMA_TO_DEVICE) { 735 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 736 737 /* 738 * Set bits to indicate WRITE_ODIRECT so we are not throttled 739 * by WBT. 740 */ 741 opf = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE; 742 /* 743 * Force writethrough using REQ_FUA if a volatile write cache 744 * is not enabled, or if initiator set the Force Unit Access bit. 745 */ 746 miter_dir = SG_MITER_TO_SG; 747 if (bdev_fua(ib_dev->ibd_bd)) { 748 if (cmd->se_cmd_flags & SCF_FUA) 749 opf |= REQ_FUA; 750 else if (!bdev_write_cache(ib_dev->ibd_bd)) 751 opf |= REQ_FUA; 752 } 753 } else { 754 opf = REQ_OP_READ; 755 miter_dir = SG_MITER_FROM_SG; 756 } 757 758 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 759 if (!ibr) 760 goto fail; 761 cmd->priv = ibr; 762 763 if (!sgl_nents) { 764 refcount_set(&ibr->pending, 1); 765 iblock_complete_cmd(cmd, BLK_STS_OK); 766 return 0; 767 } 768 769 bio = iblock_get_bio(cmd, block_lba, sgl_nents, opf); 770 if (!bio) 771 goto fail_free_ibr; 772 773 bio_list_init(&list); 774 bio_list_add(&list, bio); 775 776 refcount_set(&ibr->pending, 2); 777 bio_cnt = 1; 778 779 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) 780 sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents, 781 miter_dir); 782 783 for_each_sg(sgl, sg, sgl_nents, i) { 784 /* 785 * XXX: if the length the device accepts is shorter than the 786 * length of the S/G list entry this will cause and 787 * endless loop. Better hope no driver uses huge pages. 788 */ 789 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 790 != sg->length) { 791 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 792 rc = iblock_alloc_bip(cmd, bio, &prot_miter); 793 if (rc) 794 goto fail_put_bios; 795 } 796 797 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) { 798 iblock_submit_bios(&list); 799 bio_cnt = 0; 800 } 801 802 bio = iblock_get_bio(cmd, block_lba, sg_num, opf); 803 if (!bio) 804 goto fail_put_bios; 805 806 refcount_inc(&ibr->pending); 807 bio_list_add(&list, bio); 808 bio_cnt++; 809 } 810 811 /* Always in 512 byte units for Linux/Block */ 812 block_lba += sg->length >> SECTOR_SHIFT; 813 sg_num--; 814 } 815 816 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 817 rc = iblock_alloc_bip(cmd, bio, &prot_miter); 818 if (rc) 819 goto fail_put_bios; 820 } 821 822 iblock_submit_bios(&list); 823 iblock_complete_cmd(cmd, BLK_STS_OK); 824 return 0; 825 826 fail_put_bios: 827 while ((bio = bio_list_pop(&list))) 828 bio_put(bio); 829 fail_free_ibr: 830 kfree(ibr); 831 fail: 832 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 833 } 834 835 static sense_reason_t iblock_execute_pr_out(struct se_cmd *cmd, u8 sa, u64 key, 836 u64 sa_key, u8 type, bool aptpl) 837 { 838 struct se_device *dev = cmd->se_dev; 839 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 840 struct block_device *bdev = ib_dev->ibd_bd; 841 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 842 int ret; 843 844 if (!ops) { 845 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n"); 846 return TCM_UNSUPPORTED_SCSI_OPCODE; 847 } 848 849 switch (sa) { 850 case PRO_REGISTER: 851 case PRO_REGISTER_AND_IGNORE_EXISTING_KEY: 852 if (!ops->pr_register) { 853 pr_err("block device does not support pr_register.\n"); 854 return TCM_UNSUPPORTED_SCSI_OPCODE; 855 } 856 857 /* The block layer pr ops always enables aptpl */ 858 if (!aptpl) 859 pr_info("APTPL not set by initiator, but will be used.\n"); 860 861 ret = ops->pr_register(bdev, key, sa_key, 862 sa == PRO_REGISTER ? 0 : PR_FL_IGNORE_KEY); 863 break; 864 case PRO_RESERVE: 865 if (!ops->pr_reserve) { 866 pr_err("block_device does not support pr_reserve.\n"); 867 return TCM_UNSUPPORTED_SCSI_OPCODE; 868 } 869 870 ret = ops->pr_reserve(bdev, key, scsi_pr_type_to_block(type), 0); 871 break; 872 case PRO_CLEAR: 873 if (!ops->pr_clear) { 874 pr_err("block_device does not support pr_clear.\n"); 875 return TCM_UNSUPPORTED_SCSI_OPCODE; 876 } 877 878 ret = ops->pr_clear(bdev, key); 879 break; 880 case PRO_PREEMPT: 881 case PRO_PREEMPT_AND_ABORT: 882 if (!ops->pr_clear) { 883 pr_err("block_device does not support pr_preempt.\n"); 884 return TCM_UNSUPPORTED_SCSI_OPCODE; 885 } 886 887 ret = ops->pr_preempt(bdev, key, sa_key, 888 scsi_pr_type_to_block(type), 889 sa == PRO_PREEMPT_AND_ABORT); 890 break; 891 case PRO_RELEASE: 892 if (!ops->pr_clear) { 893 pr_err("block_device does not support pr_pclear.\n"); 894 return TCM_UNSUPPORTED_SCSI_OPCODE; 895 } 896 897 ret = ops->pr_release(bdev, key, scsi_pr_type_to_block(type)); 898 break; 899 default: 900 pr_err("Unknown PERSISTENT_RESERVE_OUT SA: 0x%02x\n", sa); 901 return TCM_UNSUPPORTED_SCSI_OPCODE; 902 } 903 904 if (!ret) 905 return TCM_NO_SENSE; 906 else if (ret == PR_STS_RESERVATION_CONFLICT) 907 return TCM_RESERVATION_CONFLICT; 908 else 909 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 910 } 911 912 static void iblock_pr_report_caps(unsigned char *param_data) 913 { 914 u16 len = 8; 915 916 put_unaligned_be16(len, ¶m_data[0]); 917 /* 918 * When using the pr_ops passthrough method we only support exporting 919 * the device through one target port because from the backend module 920 * level we can't see the target port config. As a result we only 921 * support registration directly from the I_T nexus the cmd is sent 922 * through and do not set ATP_C here. 923 * 924 * The block layer pr_ops do not support passing in initiators so 925 * we don't set SIP_C here. 926 */ 927 /* PTPL_C: Persistence across Target Power Loss bit */ 928 param_data[2] |= 0x01; 929 /* 930 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so 931 * set the TMV: Task Mask Valid bit. 932 */ 933 param_data[3] |= 0x80; 934 /* 935 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166 936 */ 937 param_data[3] |= 0x10; /* ALLOW COMMANDs field 001b */ 938 /* 939 * PTPL_A: Persistence across Target Power Loss Active bit. The block 940 * layer pr ops always enables this so report it active. 941 */ 942 param_data[3] |= 0x01; 943 /* 944 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 212 spc4r37. 945 */ 946 param_data[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */ 947 param_data[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */ 948 param_data[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */ 949 param_data[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */ 950 param_data[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */ 951 param_data[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */ 952 } 953 954 static sense_reason_t iblock_pr_read_keys(struct se_cmd *cmd, 955 unsigned char *param_data) 956 { 957 struct se_device *dev = cmd->se_dev; 958 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 959 struct block_device *bdev = ib_dev->ibd_bd; 960 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 961 int i, len, paths, data_offset; 962 struct pr_keys *keys; 963 sense_reason_t ret; 964 965 if (!ops) { 966 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n"); 967 return TCM_UNSUPPORTED_SCSI_OPCODE; 968 } 969 970 if (!ops->pr_read_keys) { 971 pr_err("Block device does not support read_keys.\n"); 972 return TCM_UNSUPPORTED_SCSI_OPCODE; 973 } 974 975 /* 976 * We don't know what's under us, but dm-multipath will register every 977 * path with the same key, so start off with enough space for 16 paths. 978 * which is not a lot of memory and should normally be enough. 979 */ 980 paths = 16; 981 retry: 982 len = 8 * paths; 983 keys = kzalloc(sizeof(*keys) + len, GFP_KERNEL); 984 if (!keys) 985 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 986 987 keys->num_keys = paths; 988 if (!ops->pr_read_keys(bdev, keys)) { 989 if (keys->num_keys > paths) { 990 kfree(keys); 991 paths *= 2; 992 goto retry; 993 } 994 } else { 995 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 996 goto free_keys; 997 } 998 999 ret = TCM_NO_SENSE; 1000 1001 put_unaligned_be32(keys->generation, ¶m_data[0]); 1002 if (!keys->num_keys) { 1003 put_unaligned_be32(0, ¶m_data[4]); 1004 goto free_keys; 1005 } 1006 1007 put_unaligned_be32(8 * keys->num_keys, ¶m_data[4]); 1008 1009 data_offset = 8; 1010 for (i = 0; i < keys->num_keys; i++) { 1011 if (data_offset + 8 > cmd->data_length) 1012 break; 1013 1014 put_unaligned_be64(keys->keys[i], ¶m_data[data_offset]); 1015 data_offset += 8; 1016 } 1017 1018 free_keys: 1019 kfree(keys); 1020 return ret; 1021 } 1022 1023 static sense_reason_t iblock_pr_read_reservation(struct se_cmd *cmd, 1024 unsigned char *param_data) 1025 { 1026 struct se_device *dev = cmd->se_dev; 1027 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 1028 struct block_device *bdev = ib_dev->ibd_bd; 1029 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 1030 struct pr_held_reservation rsv = { }; 1031 1032 if (!ops) { 1033 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n"); 1034 return TCM_UNSUPPORTED_SCSI_OPCODE; 1035 } 1036 1037 if (!ops->pr_read_reservation) { 1038 pr_err("Block device does not support read_keys.\n"); 1039 return TCM_UNSUPPORTED_SCSI_OPCODE; 1040 } 1041 1042 if (ops->pr_read_reservation(bdev, &rsv)) 1043 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 1044 1045 put_unaligned_be32(rsv.generation, ¶m_data[0]); 1046 if (!block_pr_type_to_scsi(rsv.type)) { 1047 put_unaligned_be32(0, ¶m_data[4]); 1048 return TCM_NO_SENSE; 1049 } 1050 1051 put_unaligned_be32(16, ¶m_data[4]); 1052 1053 if (cmd->data_length < 16) 1054 return TCM_NO_SENSE; 1055 put_unaligned_be64(rsv.key, ¶m_data[8]); 1056 1057 if (cmd->data_length < 22) 1058 return TCM_NO_SENSE; 1059 param_data[21] = block_pr_type_to_scsi(rsv.type); 1060 1061 return TCM_NO_SENSE; 1062 } 1063 1064 static sense_reason_t iblock_execute_pr_in(struct se_cmd *cmd, u8 sa, 1065 unsigned char *param_data) 1066 { 1067 sense_reason_t ret = TCM_NO_SENSE; 1068 1069 switch (sa) { 1070 case PRI_REPORT_CAPABILITIES: 1071 iblock_pr_report_caps(param_data); 1072 break; 1073 case PRI_READ_KEYS: 1074 ret = iblock_pr_read_keys(cmd, param_data); 1075 break; 1076 case PRI_READ_RESERVATION: 1077 ret = iblock_pr_read_reservation(cmd, param_data); 1078 break; 1079 default: 1080 pr_err("Unknown PERSISTENT_RESERVE_IN SA: 0x%02x\n", sa); 1081 return TCM_UNSUPPORTED_SCSI_OPCODE; 1082 } 1083 1084 return ret; 1085 } 1086 1087 static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev) 1088 { 1089 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 1090 struct block_device *bd = ib_dev->ibd_bd; 1091 int ret; 1092 1093 ret = bdev_alignment_offset(bd); 1094 if (ret == -1) 1095 return 0; 1096 1097 /* convert offset-bytes to offset-lbas */ 1098 return ret / bdev_logical_block_size(bd); 1099 } 1100 1101 static unsigned int iblock_get_lbppbe(struct se_device *dev) 1102 { 1103 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 1104 struct block_device *bd = ib_dev->ibd_bd; 1105 unsigned int logs_per_phys = 1106 bdev_physical_block_size(bd) / bdev_logical_block_size(bd); 1107 1108 return ilog2(logs_per_phys); 1109 } 1110 1111 static unsigned int iblock_get_io_min(struct se_device *dev) 1112 { 1113 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 1114 struct block_device *bd = ib_dev->ibd_bd; 1115 1116 return bdev_io_min(bd); 1117 } 1118 1119 static unsigned int iblock_get_io_opt(struct se_device *dev) 1120 { 1121 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 1122 struct block_device *bd = ib_dev->ibd_bd; 1123 1124 return bdev_io_opt(bd); 1125 } 1126 1127 static struct exec_cmd_ops iblock_exec_cmd_ops = { 1128 .execute_rw = iblock_execute_rw, 1129 .execute_sync_cache = iblock_execute_sync_cache, 1130 .execute_write_same = iblock_execute_write_same, 1131 .execute_unmap = iblock_execute_unmap, 1132 .execute_pr_out = iblock_execute_pr_out, 1133 .execute_pr_in = iblock_execute_pr_in, 1134 }; 1135 1136 static sense_reason_t 1137 iblock_parse_cdb(struct se_cmd *cmd) 1138 { 1139 return sbc_parse_cdb(cmd, &iblock_exec_cmd_ops); 1140 } 1141 1142 static bool iblock_get_write_cache(struct se_device *dev) 1143 { 1144 return bdev_write_cache(IBLOCK_DEV(dev)->ibd_bd); 1145 } 1146 1147 static const struct target_backend_ops iblock_ops = { 1148 .name = "iblock", 1149 .inquiry_prod = "IBLOCK", 1150 .transport_flags_changeable = TRANSPORT_FLAG_PASSTHROUGH_PGR, 1151 .inquiry_rev = IBLOCK_VERSION, 1152 .owner = THIS_MODULE, 1153 .attach_hba = iblock_attach_hba, 1154 .detach_hba = iblock_detach_hba, 1155 .alloc_device = iblock_alloc_device, 1156 .configure_device = iblock_configure_device, 1157 .destroy_device = iblock_destroy_device, 1158 .free_device = iblock_free_device, 1159 .configure_unmap = iblock_configure_unmap, 1160 .plug_device = iblock_plug_device, 1161 .unplug_device = iblock_unplug_device, 1162 .parse_cdb = iblock_parse_cdb, 1163 .set_configfs_dev_params = iblock_set_configfs_dev_params, 1164 .show_configfs_dev_params = iblock_show_configfs_dev_params, 1165 .get_device_type = sbc_get_device_type, 1166 .get_blocks = iblock_get_blocks, 1167 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas, 1168 .get_lbppbe = iblock_get_lbppbe, 1169 .get_io_min = iblock_get_io_min, 1170 .get_io_opt = iblock_get_io_opt, 1171 .get_write_cache = iblock_get_write_cache, 1172 .tb_dev_attrib_attrs = sbc_attrib_attrs, 1173 }; 1174 1175 static int __init iblock_module_init(void) 1176 { 1177 return transport_backend_register(&iblock_ops); 1178 } 1179 1180 static void __exit iblock_module_exit(void) 1181 { 1182 target_backend_unregister(&iblock_ops); 1183 } 1184 1185 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 1186 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 1187 MODULE_LICENSE("GPL"); 1188 1189 module_init(iblock_module_init); 1190 module_exit(iblock_module_exit); 1191