1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /******************************************************************************* 3 * Filename: target_core_iblock.c 4 * 5 * This file contains the Storage Engine <-> Linux BlockIO transport 6 * specific functions. 7 * 8 * (c) Copyright 2003-2013 Datera, Inc. 9 * 10 * Nicholas A. Bellinger <nab@kernel.org> 11 * 12 ******************************************************************************/ 13 14 #include <linux/string.h> 15 #include <linux/parser.h> 16 #include <linux/timer.h> 17 #include <linux/fs.h> 18 #include <linux/blkdev.h> 19 #include <linux/slab.h> 20 #include <linux/spinlock.h> 21 #include <linux/bio.h> 22 #include <linux/genhd.h> 23 #include <linux/file.h> 24 #include <linux/module.h> 25 #include <scsi/scsi_proto.h> 26 #include <asm/unaligned.h> 27 28 #include <target/target_core_base.h> 29 #include <target/target_core_backend.h> 30 31 #include "target_core_iblock.h" 32 33 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */ 34 #define IBLOCK_BIO_POOL_SIZE 128 35 36 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev) 37 { 38 return container_of(dev, struct iblock_dev, dev); 39 } 40 41 42 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 43 { 44 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 45 " Generic Target Core Stack %s\n", hba->hba_id, 46 IBLOCK_VERSION, TARGET_CORE_VERSION); 47 return 0; 48 } 49 50 static void iblock_detach_hba(struct se_hba *hba) 51 { 52 } 53 54 static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name) 55 { 56 struct iblock_dev *ib_dev = NULL; 57 58 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 59 if (!ib_dev) { 60 pr_err("Unable to allocate struct iblock_dev\n"); 61 return NULL; 62 } 63 64 ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug), 65 GFP_KERNEL); 66 if (!ib_dev->ibd_plug) 67 goto free_dev; 68 69 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name); 70 71 return &ib_dev->dev; 72 73 free_dev: 74 kfree(ib_dev); 75 return NULL; 76 } 77 78 static int iblock_configure_device(struct se_device *dev) 79 { 80 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 81 struct request_queue *q; 82 struct block_device *bd = NULL; 83 struct blk_integrity *bi; 84 fmode_t mode; 85 unsigned int max_write_zeroes_sectors; 86 int ret = -ENOMEM; 87 88 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) { 89 pr_err("Missing udev_path= parameters for IBLOCK\n"); 90 return -EINVAL; 91 } 92 93 ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); 94 if (ret) { 95 pr_err("IBLOCK: Unable to create bioset\n"); 96 goto out; 97 } 98 99 pr_debug( "IBLOCK: Claiming struct block_device: %s\n", 100 ib_dev->ibd_udev_path); 101 102 mode = FMODE_READ|FMODE_EXCL; 103 if (!ib_dev->ibd_readonly) 104 mode |= FMODE_WRITE; 105 else 106 dev->dev_flags |= DF_READ_ONLY; 107 108 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev); 109 if (IS_ERR(bd)) { 110 ret = PTR_ERR(bd); 111 goto out_free_bioset; 112 } 113 ib_dev->ibd_bd = bd; 114 115 q = bdev_get_queue(bd); 116 117 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd); 118 dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q); 119 dev->dev_attrib.hw_queue_depth = q->nr_requests; 120 121 if (target_configure_unmap_from_queue(&dev->dev_attrib, q)) 122 pr_debug("IBLOCK: BLOCK Discard support available," 123 " disabled by default\n"); 124 125 /* 126 * Enable write same emulation for IBLOCK and use 0xFFFF as 127 * the smaller WRITE_SAME(10) only has a two-byte block count. 128 */ 129 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd); 130 if (max_write_zeroes_sectors) 131 dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors; 132 else 133 dev->dev_attrib.max_write_same_len = 0xFFFF; 134 135 if (blk_queue_nonrot(q)) 136 dev->dev_attrib.is_nonrot = 1; 137 138 bi = bdev_get_integrity(bd); 139 if (bi) { 140 struct bio_set *bs = &ib_dev->ibd_bio_set; 141 142 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-IP") || 143 !strcmp(bi->profile->name, "T10-DIF-TYPE1-IP")) { 144 pr_err("IBLOCK export of blk_integrity: %s not" 145 " supported\n", bi->profile->name); 146 ret = -ENOSYS; 147 goto out_blkdev_put; 148 } 149 150 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-CRC")) { 151 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT; 152 } else if (!strcmp(bi->profile->name, "T10-DIF-TYPE1-CRC")) { 153 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT; 154 } 155 156 if (dev->dev_attrib.pi_prot_type) { 157 if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) { 158 pr_err("Unable to allocate bioset for PI\n"); 159 ret = -ENOMEM; 160 goto out_blkdev_put; 161 } 162 pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n", 163 &bs->bio_integrity_pool); 164 } 165 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type; 166 } 167 168 return 0; 169 170 out_blkdev_put: 171 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 172 out_free_bioset: 173 bioset_exit(&ib_dev->ibd_bio_set); 174 out: 175 return ret; 176 } 177 178 static void iblock_dev_call_rcu(struct rcu_head *p) 179 { 180 struct se_device *dev = container_of(p, struct se_device, rcu_head); 181 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 182 183 kfree(ib_dev->ibd_plug); 184 kfree(ib_dev); 185 } 186 187 static void iblock_free_device(struct se_device *dev) 188 { 189 call_rcu(&dev->rcu_head, iblock_dev_call_rcu); 190 } 191 192 static void iblock_destroy_device(struct se_device *dev) 193 { 194 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 195 196 if (ib_dev->ibd_bd != NULL) 197 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 198 bioset_exit(&ib_dev->ibd_bio_set); 199 } 200 201 static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev) 202 { 203 struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev); 204 struct iblock_dev_plug *ib_dev_plug; 205 206 /* 207 * Each se_device has a per cpu work this can be run from. Wwe 208 * shouldn't have multiple threads on the same cpu calling this 209 * at the same time. 210 */ 211 ib_dev_plug = &ib_dev->ibd_plug[smp_processor_id()]; 212 if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags)) 213 return NULL; 214 215 blk_start_plug(&ib_dev_plug->blk_plug); 216 return &ib_dev_plug->se_plug; 217 } 218 219 static void iblock_unplug_device(struct se_dev_plug *se_plug) 220 { 221 struct iblock_dev_plug *ib_dev_plug = container_of(se_plug, 222 struct iblock_dev_plug, se_plug); 223 224 blk_finish_plug(&ib_dev_plug->blk_plug); 225 clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags); 226 } 227 228 static unsigned long long iblock_emulate_read_cap_with_block_size( 229 struct se_device *dev, 230 struct block_device *bd, 231 struct request_queue *q) 232 { 233 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode), 234 bdev_logical_block_size(bd)) - 1); 235 u32 block_size = bdev_logical_block_size(bd); 236 237 if (block_size == dev->dev_attrib.block_size) 238 return blocks_long; 239 240 switch (block_size) { 241 case 4096: 242 switch (dev->dev_attrib.block_size) { 243 case 2048: 244 blocks_long <<= 1; 245 break; 246 case 1024: 247 blocks_long <<= 2; 248 break; 249 case 512: 250 blocks_long <<= 3; 251 break; 252 default: 253 break; 254 } 255 break; 256 case 2048: 257 switch (dev->dev_attrib.block_size) { 258 case 4096: 259 blocks_long >>= 1; 260 break; 261 case 1024: 262 blocks_long <<= 1; 263 break; 264 case 512: 265 blocks_long <<= 2; 266 break; 267 default: 268 break; 269 } 270 break; 271 case 1024: 272 switch (dev->dev_attrib.block_size) { 273 case 4096: 274 blocks_long >>= 2; 275 break; 276 case 2048: 277 blocks_long >>= 1; 278 break; 279 case 512: 280 blocks_long <<= 1; 281 break; 282 default: 283 break; 284 } 285 break; 286 case 512: 287 switch (dev->dev_attrib.block_size) { 288 case 4096: 289 blocks_long >>= 3; 290 break; 291 case 2048: 292 blocks_long >>= 2; 293 break; 294 case 1024: 295 blocks_long >>= 1; 296 break; 297 default: 298 break; 299 } 300 break; 301 default: 302 break; 303 } 304 305 return blocks_long; 306 } 307 308 static void iblock_complete_cmd(struct se_cmd *cmd) 309 { 310 struct iblock_req *ibr = cmd->priv; 311 u8 status; 312 313 if (!refcount_dec_and_test(&ibr->pending)) 314 return; 315 316 if (atomic_read(&ibr->ib_bio_err_cnt)) 317 status = SAM_STAT_CHECK_CONDITION; 318 else 319 status = SAM_STAT_GOOD; 320 321 target_complete_cmd(cmd, status); 322 kfree(ibr); 323 } 324 325 static void iblock_bio_done(struct bio *bio) 326 { 327 struct se_cmd *cmd = bio->bi_private; 328 struct iblock_req *ibr = cmd->priv; 329 330 if (bio->bi_status) { 331 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status); 332 /* 333 * Bump the ib_bio_err_cnt and release bio. 334 */ 335 atomic_inc(&ibr->ib_bio_err_cnt); 336 smp_mb__after_atomic(); 337 } 338 339 bio_put(bio); 340 341 iblock_complete_cmd(cmd); 342 } 343 344 static struct bio *iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num, 345 unsigned int opf) 346 { 347 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 348 struct bio *bio; 349 350 /* 351 * Only allocate as many vector entries as the bio code allows us to, 352 * we'll loop later on until we have handled the whole request. 353 */ 354 bio = bio_alloc_bioset(GFP_NOIO, bio_max_segs(sg_num), 355 &ib_dev->ibd_bio_set); 356 if (!bio) { 357 pr_err("Unable to allocate memory for bio\n"); 358 return NULL; 359 } 360 361 bio_set_dev(bio, ib_dev->ibd_bd); 362 bio->bi_private = cmd; 363 bio->bi_end_io = &iblock_bio_done; 364 bio->bi_iter.bi_sector = lba; 365 bio->bi_opf = opf; 366 367 return bio; 368 } 369 370 static void iblock_submit_bios(struct bio_list *list) 371 { 372 struct blk_plug plug; 373 struct bio *bio; 374 /* 375 * The block layer handles nested plugs, so just plug/unplug to handle 376 * fabric drivers that didn't support batching and multi bio cmds. 377 */ 378 blk_start_plug(&plug); 379 while ((bio = bio_list_pop(list))) 380 submit_bio(bio); 381 blk_finish_plug(&plug); 382 } 383 384 static void iblock_end_io_flush(struct bio *bio) 385 { 386 struct se_cmd *cmd = bio->bi_private; 387 388 if (bio->bi_status) 389 pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status); 390 391 if (cmd) { 392 if (bio->bi_status) 393 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION); 394 else 395 target_complete_cmd(cmd, SAM_STAT_GOOD); 396 } 397 398 bio_put(bio); 399 } 400 401 /* 402 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must 403 * always flush the whole cache. 404 */ 405 static sense_reason_t 406 iblock_execute_sync_cache(struct se_cmd *cmd) 407 { 408 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev); 409 int immed = (cmd->t_task_cdb[1] & 0x2); 410 struct bio *bio; 411 412 /* 413 * If the Immediate bit is set, queue up the GOOD response 414 * for this SYNCHRONIZE_CACHE op. 415 */ 416 if (immed) 417 target_complete_cmd(cmd, SAM_STAT_GOOD); 418 419 bio = bio_alloc(GFP_KERNEL, 0); 420 bio->bi_end_io = iblock_end_io_flush; 421 bio_set_dev(bio, ib_dev->ibd_bd); 422 bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; 423 if (!immed) 424 bio->bi_private = cmd; 425 submit_bio(bio); 426 return 0; 427 } 428 429 static sense_reason_t 430 iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 431 { 432 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 433 struct se_device *dev = cmd->se_dev; 434 int ret; 435 436 ret = blkdev_issue_discard(bdev, 437 target_to_linux_sector(dev, lba), 438 target_to_linux_sector(dev, nolb), 439 GFP_KERNEL, 0); 440 if (ret < 0) { 441 pr_err("blkdev_issue_discard() failed: %d\n", ret); 442 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 443 } 444 445 return 0; 446 } 447 448 static sense_reason_t 449 iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd) 450 { 451 struct se_device *dev = cmd->se_dev; 452 struct scatterlist *sg = &cmd->t_data_sg[0]; 453 unsigned char *buf, *not_zero; 454 int ret; 455 456 buf = kmap(sg_page(sg)) + sg->offset; 457 if (!buf) 458 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 459 /* 460 * Fall back to block_execute_write_same() slow-path if 461 * incoming WRITE_SAME payload does not contain zeros. 462 */ 463 not_zero = memchr_inv(buf, 0x00, cmd->data_length); 464 kunmap(sg_page(sg)); 465 466 if (not_zero) 467 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 468 469 ret = blkdev_issue_zeroout(bdev, 470 target_to_linux_sector(dev, cmd->t_task_lba), 471 target_to_linux_sector(dev, 472 sbc_get_write_same_sectors(cmd)), 473 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); 474 if (ret) 475 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 476 477 target_complete_cmd(cmd, GOOD); 478 return 0; 479 } 480 481 static sense_reason_t 482 iblock_execute_write_same(struct se_cmd *cmd) 483 { 484 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; 485 struct iblock_req *ibr; 486 struct scatterlist *sg; 487 struct bio *bio; 488 struct bio_list list; 489 struct se_device *dev = cmd->se_dev; 490 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); 491 sector_t sectors = target_to_linux_sector(dev, 492 sbc_get_write_same_sectors(cmd)); 493 494 if (cmd->prot_op) { 495 pr_err("WRITE_SAME: Protection information with IBLOCK" 496 " backends not supported\n"); 497 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 498 } 499 sg = &cmd->t_data_sg[0]; 500 501 if (cmd->t_data_nents > 1 || 502 sg->length != cmd->se_dev->dev_attrib.block_size) { 503 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 504 " block_size: %u\n", cmd->t_data_nents, sg->length, 505 cmd->se_dev->dev_attrib.block_size); 506 return TCM_INVALID_CDB_FIELD; 507 } 508 509 if (bdev_write_zeroes_sectors(bdev)) { 510 if (!iblock_execute_zero_out(bdev, cmd)) 511 return 0; 512 } 513 514 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 515 if (!ibr) 516 goto fail; 517 cmd->priv = ibr; 518 519 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); 520 if (!bio) 521 goto fail_free_ibr; 522 523 bio_list_init(&list); 524 bio_list_add(&list, bio); 525 526 refcount_set(&ibr->pending, 1); 527 528 while (sectors) { 529 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) 530 != sg->length) { 531 532 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); 533 if (!bio) 534 goto fail_put_bios; 535 536 refcount_inc(&ibr->pending); 537 bio_list_add(&list, bio); 538 } 539 540 /* Always in 512 byte units for Linux/Block */ 541 block_lba += sg->length >> SECTOR_SHIFT; 542 sectors -= sg->length >> SECTOR_SHIFT; 543 } 544 545 iblock_submit_bios(&list); 546 return 0; 547 548 fail_put_bios: 549 while ((bio = bio_list_pop(&list))) 550 bio_put(bio); 551 fail_free_ibr: 552 kfree(ibr); 553 fail: 554 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 555 } 556 557 enum { 558 Opt_udev_path, Opt_readonly, Opt_force, Opt_err 559 }; 560 561 static match_table_t tokens = { 562 {Opt_udev_path, "udev_path=%s"}, 563 {Opt_readonly, "readonly=%d"}, 564 {Opt_force, "force=%d"}, 565 {Opt_err, NULL} 566 }; 567 568 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev, 569 const char *page, ssize_t count) 570 { 571 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 572 char *orig, *ptr, *arg_p, *opts; 573 substring_t args[MAX_OPT_ARGS]; 574 int ret = 0, token; 575 unsigned long tmp_readonly; 576 577 opts = kstrdup(page, GFP_KERNEL); 578 if (!opts) 579 return -ENOMEM; 580 581 orig = opts; 582 583 while ((ptr = strsep(&opts, ",\n")) != NULL) { 584 if (!*ptr) 585 continue; 586 587 token = match_token(ptr, tokens, args); 588 switch (token) { 589 case Opt_udev_path: 590 if (ib_dev->ibd_bd) { 591 pr_err("Unable to set udev_path= while" 592 " ib_dev->ibd_bd exists\n"); 593 ret = -EEXIST; 594 goto out; 595 } 596 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0], 597 SE_UDEV_PATH_LEN) == 0) { 598 ret = -EINVAL; 599 break; 600 } 601 pr_debug("IBLOCK: Referencing UDEV path: %s\n", 602 ib_dev->ibd_udev_path); 603 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 604 break; 605 case Opt_readonly: 606 arg_p = match_strdup(&args[0]); 607 if (!arg_p) { 608 ret = -ENOMEM; 609 break; 610 } 611 ret = kstrtoul(arg_p, 0, &tmp_readonly); 612 kfree(arg_p); 613 if (ret < 0) { 614 pr_err("kstrtoul() failed for" 615 " readonly=\n"); 616 goto out; 617 } 618 ib_dev->ibd_readonly = tmp_readonly; 619 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly); 620 break; 621 case Opt_force: 622 break; 623 default: 624 break; 625 } 626 } 627 628 out: 629 kfree(orig); 630 return (!ret) ? count : ret; 631 } 632 633 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b) 634 { 635 struct iblock_dev *ib_dev = IBLOCK_DEV(dev); 636 struct block_device *bd = ib_dev->ibd_bd; 637 char buf[BDEVNAME_SIZE]; 638 ssize_t bl = 0; 639 640 if (bd) 641 bl += sprintf(b + bl, "iBlock device: %s", 642 bdevname(bd, buf)); 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