1 /******************************************************************************* 2 * Filename: target_core_iblock.c 3 * 4 * This file contains the Storage Engine <-> Linux BlockIO transport 5 * specific functions. 6 * 7 * Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc. 8 * Copyright (c) 2005, 2006, 2007 SBE, Inc. 9 * Copyright (c) 2007-2010 Rising Tide Systems 10 * Copyright (c) 2008-2010 Linux-iSCSI.org 11 * 12 * Nicholas A. Bellinger <nab@kernel.org> 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License as published by 16 * the Free Software Foundation; either version 2 of the License, or 17 * (at your option) any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22 * GNU General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with this program; if not, write to the Free Software 26 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 27 * 28 ******************************************************************************/ 29 30 #include <linux/version.h> 31 #include <linux/string.h> 32 #include <linux/parser.h> 33 #include <linux/timer.h> 34 #include <linux/fs.h> 35 #include <linux/blkdev.h> 36 #include <linux/slab.h> 37 #include <linux/spinlock.h> 38 #include <linux/bio.h> 39 #include <linux/genhd.h> 40 #include <linux/file.h> 41 #include <scsi/scsi.h> 42 #include <scsi/scsi_host.h> 43 44 #include <target/target_core_base.h> 45 #include <target/target_core_device.h> 46 #include <target/target_core_transport.h> 47 48 #include "target_core_iblock.h" 49 50 static struct se_subsystem_api iblock_template; 51 52 static void iblock_bio_done(struct bio *, int); 53 54 /* iblock_attach_hba(): (Part of se_subsystem_api_t template) 55 * 56 * 57 */ 58 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 59 { 60 struct iblock_hba *ib_host; 61 62 ib_host = kzalloc(sizeof(struct iblock_hba), GFP_KERNEL); 63 if (!ib_host) { 64 pr_err("Unable to allocate memory for" 65 " struct iblock_hba\n"); 66 return -ENOMEM; 67 } 68 69 ib_host->iblock_host_id = host_id; 70 71 hba->hba_ptr = ib_host; 72 73 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 74 " Generic Target Core Stack %s\n", hba->hba_id, 75 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION); 76 77 pr_debug("CORE_HBA[%d] - Attached iBlock HBA: %u to Generic\n", 78 hba->hba_id, ib_host->iblock_host_id); 79 80 return 0; 81 } 82 83 static void iblock_detach_hba(struct se_hba *hba) 84 { 85 struct iblock_hba *ib_host = hba->hba_ptr; 86 87 pr_debug("CORE_HBA[%d] - Detached iBlock HBA: %u from Generic" 88 " Target Core\n", hba->hba_id, ib_host->iblock_host_id); 89 90 kfree(ib_host); 91 hba->hba_ptr = NULL; 92 } 93 94 static void *iblock_allocate_virtdevice(struct se_hba *hba, const char *name) 95 { 96 struct iblock_dev *ib_dev = NULL; 97 struct iblock_hba *ib_host = hba->hba_ptr; 98 99 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 100 if (!ib_dev) { 101 pr_err("Unable to allocate struct iblock_dev\n"); 102 return NULL; 103 } 104 ib_dev->ibd_host = ib_host; 105 106 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name); 107 108 return ib_dev; 109 } 110 111 static struct se_device *iblock_create_virtdevice( 112 struct se_hba *hba, 113 struct se_subsystem_dev *se_dev, 114 void *p) 115 { 116 struct iblock_dev *ib_dev = p; 117 struct se_device *dev; 118 struct se_dev_limits dev_limits; 119 struct block_device *bd = NULL; 120 struct request_queue *q; 121 struct queue_limits *limits; 122 u32 dev_flags = 0; 123 int ret = -EINVAL; 124 125 if (!ib_dev) { 126 pr_err("Unable to locate struct iblock_dev parameter\n"); 127 return ERR_PTR(ret); 128 } 129 memset(&dev_limits, 0, sizeof(struct se_dev_limits)); 130 /* 131 * These settings need to be made tunable.. 132 */ 133 ib_dev->ibd_bio_set = bioset_create(32, 64); 134 if (!ib_dev->ibd_bio_set) { 135 pr_err("IBLOCK: Unable to create bioset()\n"); 136 return ERR_PTR(-ENOMEM); 137 } 138 pr_debug("IBLOCK: Created bio_set()\n"); 139 /* 140 * iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path 141 * must already have been set in order for echo 1 > $HBA/$DEV/enable to run. 142 */ 143 pr_debug( "IBLOCK: Claiming struct block_device: %s\n", 144 ib_dev->ibd_udev_path); 145 146 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, 147 FMODE_WRITE|FMODE_READ|FMODE_EXCL, ib_dev); 148 if (IS_ERR(bd)) { 149 ret = PTR_ERR(bd); 150 goto failed; 151 } 152 /* 153 * Setup the local scope queue_limits from struct request_queue->limits 154 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits. 155 */ 156 q = bdev_get_queue(bd); 157 limits = &dev_limits.limits; 158 limits->logical_block_size = bdev_logical_block_size(bd); 159 limits->max_hw_sectors = queue_max_hw_sectors(q); 160 limits->max_sectors = queue_max_sectors(q); 161 dev_limits.hw_queue_depth = q->nr_requests; 162 dev_limits.queue_depth = q->nr_requests; 163 164 ib_dev->ibd_bd = bd; 165 166 dev = transport_add_device_to_core_hba(hba, 167 &iblock_template, se_dev, dev_flags, ib_dev, 168 &dev_limits, "IBLOCK", IBLOCK_VERSION); 169 if (!dev) 170 goto failed; 171 172 /* 173 * Check if the underlying struct block_device request_queue supports 174 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM 175 * in ATA and we need to set TPE=1 176 */ 177 if (blk_queue_discard(q)) { 178 dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count = 179 q->limits.max_discard_sectors; 180 /* 181 * Currently hardcoded to 1 in Linux/SCSI code.. 182 */ 183 dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count = 1; 184 dev->se_sub_dev->se_dev_attrib.unmap_granularity = 185 q->limits.discard_granularity; 186 dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment = 187 q->limits.discard_alignment; 188 189 pr_debug("IBLOCK: BLOCK Discard support available," 190 " disabled by default\n"); 191 } 192 193 if (blk_queue_nonrot(q)) 194 dev->se_sub_dev->se_dev_attrib.is_nonrot = 1; 195 196 return dev; 197 198 failed: 199 if (ib_dev->ibd_bio_set) { 200 bioset_free(ib_dev->ibd_bio_set); 201 ib_dev->ibd_bio_set = NULL; 202 } 203 ib_dev->ibd_bd = NULL; 204 return ERR_PTR(ret); 205 } 206 207 static void iblock_free_device(void *p) 208 { 209 struct iblock_dev *ib_dev = p; 210 211 if (ib_dev->ibd_bd != NULL) 212 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 213 if (ib_dev->ibd_bio_set != NULL) 214 bioset_free(ib_dev->ibd_bio_set); 215 kfree(ib_dev); 216 } 217 218 static inline struct iblock_req *IBLOCK_REQ(struct se_task *task) 219 { 220 return container_of(task, struct iblock_req, ib_task); 221 } 222 223 static struct se_task * 224 iblock_alloc_task(unsigned char *cdb) 225 { 226 struct iblock_req *ib_req; 227 228 ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 229 if (!ib_req) { 230 pr_err("Unable to allocate memory for struct iblock_req\n"); 231 return NULL; 232 } 233 234 atomic_set(&ib_req->ib_bio_cnt, 0); 235 return &ib_req->ib_task; 236 } 237 238 static unsigned long long iblock_emulate_read_cap_with_block_size( 239 struct se_device *dev, 240 struct block_device *bd, 241 struct request_queue *q) 242 { 243 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode), 244 bdev_logical_block_size(bd)) - 1); 245 u32 block_size = bdev_logical_block_size(bd); 246 247 if (block_size == dev->se_sub_dev->se_dev_attrib.block_size) 248 return blocks_long; 249 250 switch (block_size) { 251 case 4096: 252 switch (dev->se_sub_dev->se_dev_attrib.block_size) { 253 case 2048: 254 blocks_long <<= 1; 255 break; 256 case 1024: 257 blocks_long <<= 2; 258 break; 259 case 512: 260 blocks_long <<= 3; 261 default: 262 break; 263 } 264 break; 265 case 2048: 266 switch (dev->se_sub_dev->se_dev_attrib.block_size) { 267 case 4096: 268 blocks_long >>= 1; 269 break; 270 case 1024: 271 blocks_long <<= 1; 272 break; 273 case 512: 274 blocks_long <<= 2; 275 break; 276 default: 277 break; 278 } 279 break; 280 case 1024: 281 switch (dev->se_sub_dev->se_dev_attrib.block_size) { 282 case 4096: 283 blocks_long >>= 2; 284 break; 285 case 2048: 286 blocks_long >>= 1; 287 break; 288 case 512: 289 blocks_long <<= 1; 290 break; 291 default: 292 break; 293 } 294 break; 295 case 512: 296 switch (dev->se_sub_dev->se_dev_attrib.block_size) { 297 case 4096: 298 blocks_long >>= 3; 299 break; 300 case 2048: 301 blocks_long >>= 2; 302 break; 303 case 1024: 304 blocks_long >>= 1; 305 break; 306 default: 307 break; 308 } 309 break; 310 default: 311 break; 312 } 313 314 return blocks_long; 315 } 316 317 /* 318 * Emulate SYCHRONIZE_CACHE_* 319 */ 320 static void iblock_emulate_sync_cache(struct se_task *task) 321 { 322 struct se_cmd *cmd = task->task_se_cmd; 323 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr; 324 int immed = (cmd->t_task_cdb[1] & 0x2); 325 sector_t error_sector; 326 int ret; 327 328 /* 329 * If the Immediate bit is set, queue up the GOOD response 330 * for this SYNCHRONIZE_CACHE op 331 */ 332 if (immed) 333 transport_complete_sync_cache(cmd, 1); 334 335 /* 336 * blkdev_issue_flush() does not support a specifying a range, so 337 * we have to flush the entire cache. 338 */ 339 ret = blkdev_issue_flush(ib_dev->ibd_bd, GFP_KERNEL, &error_sector); 340 if (ret != 0) { 341 pr_err("IBLOCK: block_issue_flush() failed: %d " 342 " error_sector: %llu\n", ret, 343 (unsigned long long)error_sector); 344 } 345 346 if (!immed) 347 transport_complete_sync_cache(cmd, ret == 0); 348 } 349 350 /* 351 * Tell TCM Core that we are capable of WriteCache emulation for 352 * an underlying struct se_device. 353 */ 354 static int iblock_emulated_write_cache(struct se_device *dev) 355 { 356 return 1; 357 } 358 359 static int iblock_emulated_dpo(struct se_device *dev) 360 { 361 return 0; 362 } 363 364 /* 365 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs 366 * for TYPE_DISK. 367 */ 368 static int iblock_emulated_fua_write(struct se_device *dev) 369 { 370 return 1; 371 } 372 373 static int iblock_emulated_fua_read(struct se_device *dev) 374 { 375 return 0; 376 } 377 378 static int iblock_do_task(struct se_task *task) 379 { 380 struct se_device *dev = task->task_se_cmd->se_dev; 381 struct iblock_req *req = IBLOCK_REQ(task); 382 struct bio *bio = req->ib_bio, *nbio = NULL; 383 struct blk_plug plug; 384 int rw; 385 386 if (task->task_data_direction == DMA_TO_DEVICE) { 387 /* 388 * Force data to disk if we pretend to not have a volatile 389 * write cache, or the initiator set the Force Unit Access bit. 390 */ 391 if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache == 0 || 392 (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 && 393 task->task_se_cmd->t_tasks_fua)) 394 rw = WRITE_FUA; 395 else 396 rw = WRITE; 397 } else { 398 rw = READ; 399 } 400 401 blk_start_plug(&plug); 402 while (bio) { 403 nbio = bio->bi_next; 404 bio->bi_next = NULL; 405 pr_debug("Calling submit_bio() task: %p bio: %p" 406 " bio->bi_sector: %llu\n", task, bio, 407 (unsigned long long)bio->bi_sector); 408 409 submit_bio(rw, bio); 410 bio = nbio; 411 } 412 blk_finish_plug(&plug); 413 414 return PYX_TRANSPORT_SENT_TO_TRANSPORT; 415 } 416 417 static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range) 418 { 419 struct iblock_dev *ibd = dev->dev_ptr; 420 struct block_device *bd = ibd->ibd_bd; 421 int barrier = 0; 422 423 return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier); 424 } 425 426 static void iblock_free_task(struct se_task *task) 427 { 428 struct iblock_req *req = IBLOCK_REQ(task); 429 struct bio *bio, *hbio = req->ib_bio; 430 /* 431 * We only release the bio(s) here if iblock_bio_done() has not called 432 * bio_put() -> iblock_bio_destructor(). 433 */ 434 while (hbio != NULL) { 435 bio = hbio; 436 hbio = hbio->bi_next; 437 bio->bi_next = NULL; 438 bio_put(bio); 439 } 440 441 kfree(req); 442 } 443 444 enum { 445 Opt_udev_path, Opt_force, Opt_err 446 }; 447 448 static match_table_t tokens = { 449 {Opt_udev_path, "udev_path=%s"}, 450 {Opt_force, "force=%d"}, 451 {Opt_err, NULL} 452 }; 453 454 static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba, 455 struct se_subsystem_dev *se_dev, 456 const char *page, ssize_t count) 457 { 458 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr; 459 char *orig, *ptr, *arg_p, *opts; 460 substring_t args[MAX_OPT_ARGS]; 461 int ret = 0, token; 462 463 opts = kstrdup(page, GFP_KERNEL); 464 if (!opts) 465 return -ENOMEM; 466 467 orig = opts; 468 469 while ((ptr = strsep(&opts, ",")) != NULL) { 470 if (!*ptr) 471 continue; 472 473 token = match_token(ptr, tokens, args); 474 switch (token) { 475 case Opt_udev_path: 476 if (ib_dev->ibd_bd) { 477 pr_err("Unable to set udev_path= while" 478 " ib_dev->ibd_bd exists\n"); 479 ret = -EEXIST; 480 goto out; 481 } 482 arg_p = match_strdup(&args[0]); 483 if (!arg_p) { 484 ret = -ENOMEM; 485 break; 486 } 487 snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN, 488 "%s", arg_p); 489 kfree(arg_p); 490 pr_debug("IBLOCK: Referencing UDEV path: %s\n", 491 ib_dev->ibd_udev_path); 492 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 493 break; 494 case Opt_force: 495 break; 496 default: 497 break; 498 } 499 } 500 501 out: 502 kfree(orig); 503 return (!ret) ? count : ret; 504 } 505 506 static ssize_t iblock_check_configfs_dev_params( 507 struct se_hba *hba, 508 struct se_subsystem_dev *se_dev) 509 { 510 struct iblock_dev *ibd = se_dev->se_dev_su_ptr; 511 512 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) { 513 pr_err("Missing udev_path= parameters for IBLOCK\n"); 514 return -EINVAL; 515 } 516 517 return 0; 518 } 519 520 static ssize_t iblock_show_configfs_dev_params( 521 struct se_hba *hba, 522 struct se_subsystem_dev *se_dev, 523 char *b) 524 { 525 struct iblock_dev *ibd = se_dev->se_dev_su_ptr; 526 struct block_device *bd = ibd->ibd_bd; 527 char buf[BDEVNAME_SIZE]; 528 ssize_t bl = 0; 529 530 if (bd) 531 bl += sprintf(b + bl, "iBlock device: %s", 532 bdevname(bd, buf)); 533 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) { 534 bl += sprintf(b + bl, " UDEV PATH: %s\n", 535 ibd->ibd_udev_path); 536 } else 537 bl += sprintf(b + bl, "\n"); 538 539 bl += sprintf(b + bl, " "); 540 if (bd) { 541 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 542 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ? 543 "" : (bd->bd_holder == (struct iblock_dev *)ibd) ? 544 "CLAIMED: IBLOCK" : "CLAIMED: OS"); 545 } else { 546 bl += sprintf(b + bl, "Major: 0 Minor: 0\n"); 547 } 548 549 return bl; 550 } 551 552 static void iblock_bio_destructor(struct bio *bio) 553 { 554 struct se_task *task = bio->bi_private; 555 struct iblock_dev *ib_dev = task->se_dev->dev_ptr; 556 557 bio_free(bio, ib_dev->ibd_bio_set); 558 } 559 560 static struct bio *iblock_get_bio( 561 struct se_task *task, 562 struct iblock_req *ib_req, 563 struct iblock_dev *ib_dev, 564 int *ret, 565 sector_t lba, 566 u32 sg_num) 567 { 568 struct bio *bio; 569 570 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set); 571 if (!bio) { 572 pr_err("Unable to allocate memory for bio\n"); 573 *ret = PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES; 574 return NULL; 575 } 576 577 pr_debug("Allocated bio: %p task_sg_nents: %u using ibd_bio_set:" 578 " %p\n", bio, task->task_sg_nents, ib_dev->ibd_bio_set); 579 pr_debug("Allocated bio: %p task_size: %u\n", bio, task->task_size); 580 581 bio->bi_bdev = ib_dev->ibd_bd; 582 bio->bi_private = task; 583 bio->bi_destructor = iblock_bio_destructor; 584 bio->bi_end_io = &iblock_bio_done; 585 bio->bi_sector = lba; 586 atomic_inc(&ib_req->ib_bio_cnt); 587 588 pr_debug("Set bio->bi_sector: %llu\n", (unsigned long long)bio->bi_sector); 589 pr_debug("Set ib_req->ib_bio_cnt: %d\n", 590 atomic_read(&ib_req->ib_bio_cnt)); 591 return bio; 592 } 593 594 static int iblock_map_data_SG(struct se_task *task) 595 { 596 struct se_cmd *cmd = task->task_se_cmd; 597 struct se_device *dev = cmd->se_dev; 598 struct iblock_dev *ib_dev = task->se_dev->dev_ptr; 599 struct iblock_req *ib_req = IBLOCK_REQ(task); 600 struct bio *bio = NULL, *hbio = NULL, *tbio = NULL; 601 struct scatterlist *sg; 602 int ret = 0; 603 u32 i, sg_num = task->task_sg_nents; 604 sector_t block_lba; 605 /* 606 * Do starting conversion up from non 512-byte blocksize with 607 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO. 608 */ 609 if (dev->se_sub_dev->se_dev_attrib.block_size == 4096) 610 block_lba = (task->task_lba << 3); 611 else if (dev->se_sub_dev->se_dev_attrib.block_size == 2048) 612 block_lba = (task->task_lba << 2); 613 else if (dev->se_sub_dev->se_dev_attrib.block_size == 1024) 614 block_lba = (task->task_lba << 1); 615 else if (dev->se_sub_dev->se_dev_attrib.block_size == 512) 616 block_lba = task->task_lba; 617 else { 618 pr_err("Unsupported SCSI -> BLOCK LBA conversion:" 619 " %u\n", dev->se_sub_dev->se_dev_attrib.block_size); 620 return PYX_TRANSPORT_LU_COMM_FAILURE; 621 } 622 623 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, block_lba, sg_num); 624 if (!bio) 625 return ret; 626 627 ib_req->ib_bio = bio; 628 hbio = tbio = bio; 629 /* 630 * Use fs/bio.c:bio_add_pages() to setup the bio_vec maplist 631 * from task->task_sg -> struct scatterlist memory. 632 */ 633 for_each_sg(task->task_sg, sg, task->task_sg_nents, i) { 634 pr_debug("task: %p bio: %p Calling bio_add_page(): page:" 635 " %p len: %u offset: %u\n", task, bio, sg_page(sg), 636 sg->length, sg->offset); 637 again: 638 ret = bio_add_page(bio, sg_page(sg), sg->length, sg->offset); 639 if (ret != sg->length) { 640 641 pr_debug("*** Set bio->bi_sector: %llu\n", 642 (unsigned long long)bio->bi_sector); 643 pr_debug("** task->task_size: %u\n", 644 task->task_size); 645 pr_debug("*** bio->bi_max_vecs: %u\n", 646 bio->bi_max_vecs); 647 pr_debug("*** bio->bi_vcnt: %u\n", 648 bio->bi_vcnt); 649 650 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, 651 block_lba, sg_num); 652 if (!bio) 653 goto fail; 654 655 tbio = tbio->bi_next = bio; 656 pr_debug("-----------------> Added +1 bio: %p to" 657 " list, Going to again\n", bio); 658 goto again; 659 } 660 /* Always in 512 byte units for Linux/Block */ 661 block_lba += sg->length >> IBLOCK_LBA_SHIFT; 662 sg_num--; 663 pr_debug("task: %p bio-add_page() passed!, decremented" 664 " sg_num to %u\n", task, sg_num); 665 pr_debug("task: %p bio_add_page() passed!, increased lba" 666 " to %llu\n", task, (unsigned long long)block_lba); 667 pr_debug("task: %p bio_add_page() passed!, bio->bi_vcnt:" 668 " %u\n", task, bio->bi_vcnt); 669 } 670 671 return 0; 672 fail: 673 while (hbio) { 674 bio = hbio; 675 hbio = hbio->bi_next; 676 bio->bi_next = NULL; 677 bio_put(bio); 678 } 679 return ret; 680 } 681 682 static unsigned char *iblock_get_cdb(struct se_task *task) 683 { 684 return IBLOCK_REQ(task)->ib_scsi_cdb; 685 } 686 687 static u32 iblock_get_device_rev(struct se_device *dev) 688 { 689 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */ 690 } 691 692 static u32 iblock_get_device_type(struct se_device *dev) 693 { 694 return TYPE_DISK; 695 } 696 697 static sector_t iblock_get_blocks(struct se_device *dev) 698 { 699 struct iblock_dev *ibd = dev->dev_ptr; 700 struct block_device *bd = ibd->ibd_bd; 701 struct request_queue *q = bdev_get_queue(bd); 702 703 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 704 } 705 706 static void iblock_bio_done(struct bio *bio, int err) 707 { 708 struct se_task *task = bio->bi_private; 709 struct iblock_req *ibr = IBLOCK_REQ(task); 710 /* 711 * Set -EIO if !BIO_UPTODATE and the passed is still err=0 712 */ 713 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err) 714 err = -EIO; 715 716 if (err != 0) { 717 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p," 718 " err: %d\n", bio, err); 719 /* 720 * Bump the ib_bio_err_cnt and release bio. 721 */ 722 atomic_inc(&ibr->ib_bio_err_cnt); 723 smp_mb__after_atomic_inc(); 724 bio_put(bio); 725 /* 726 * Wait to complete the task until the last bio as completed. 727 */ 728 if (!atomic_dec_and_test(&ibr->ib_bio_cnt)) 729 return; 730 731 ibr->ib_bio = NULL; 732 transport_complete_task(task, 0); 733 return; 734 } 735 pr_debug("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n", 736 task, bio, task->task_lba, (unsigned long long)bio->bi_sector, err); 737 /* 738 * bio_put() will call iblock_bio_destructor() to release the bio back 739 * to ibr->ib_bio_set. 740 */ 741 bio_put(bio); 742 /* 743 * Wait to complete the task until the last bio as completed. 744 */ 745 if (!atomic_dec_and_test(&ibr->ib_bio_cnt)) 746 return; 747 /* 748 * Return GOOD status for task if zero ib_bio_err_cnt exists. 749 */ 750 ibr->ib_bio = NULL; 751 transport_complete_task(task, (!atomic_read(&ibr->ib_bio_err_cnt))); 752 } 753 754 static struct se_subsystem_api iblock_template = { 755 .name = "iblock", 756 .owner = THIS_MODULE, 757 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, 758 .map_data_SG = iblock_map_data_SG, 759 .attach_hba = iblock_attach_hba, 760 .detach_hba = iblock_detach_hba, 761 .allocate_virtdevice = iblock_allocate_virtdevice, 762 .create_virtdevice = iblock_create_virtdevice, 763 .free_device = iblock_free_device, 764 .dpo_emulated = iblock_emulated_dpo, 765 .fua_write_emulated = iblock_emulated_fua_write, 766 .fua_read_emulated = iblock_emulated_fua_read, 767 .write_cache_emulated = iblock_emulated_write_cache, 768 .alloc_task = iblock_alloc_task, 769 .do_task = iblock_do_task, 770 .do_discard = iblock_do_discard, 771 .do_sync_cache = iblock_emulate_sync_cache, 772 .free_task = iblock_free_task, 773 .check_configfs_dev_params = iblock_check_configfs_dev_params, 774 .set_configfs_dev_params = iblock_set_configfs_dev_params, 775 .show_configfs_dev_params = iblock_show_configfs_dev_params, 776 .get_cdb = iblock_get_cdb, 777 .get_device_rev = iblock_get_device_rev, 778 .get_device_type = iblock_get_device_type, 779 .get_blocks = iblock_get_blocks, 780 }; 781 782 static int __init iblock_module_init(void) 783 { 784 return transport_subsystem_register(&iblock_template); 785 } 786 787 static void iblock_module_exit(void) 788 { 789 transport_subsystem_release(&iblock_template); 790 } 791 792 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 793 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 794 MODULE_LICENSE("GPL"); 795 796 module_init(iblock_module_init); 797 module_exit(iblock_module_exit); 798