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/smp_lock.h> 39 #include <linux/bio.h> 40 #include <linux/genhd.h> 41 #include <linux/file.h> 42 #include <scsi/scsi.h> 43 #include <scsi/scsi_host.h> 44 45 #include <target/target_core_base.h> 46 #include <target/target_core_device.h> 47 #include <target/target_core_transport.h> 48 49 #include "target_core_iblock.h" 50 51 #if 0 52 #define DEBUG_IBLOCK(x...) printk(x) 53 #else 54 #define DEBUG_IBLOCK(x...) 55 #endif 56 57 static struct se_subsystem_api iblock_template; 58 59 static void iblock_bio_done(struct bio *, int); 60 61 /* iblock_attach_hba(): (Part of se_subsystem_api_t template) 62 * 63 * 64 */ 65 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 66 { 67 struct iblock_hba *ib_host; 68 69 ib_host = kzalloc(sizeof(struct iblock_hba), GFP_KERNEL); 70 if (!(ib_host)) { 71 printk(KERN_ERR "Unable to allocate memory for" 72 " struct iblock_hba\n"); 73 return -ENOMEM; 74 } 75 76 ib_host->iblock_host_id = host_id; 77 78 atomic_set(&hba->left_queue_depth, IBLOCK_HBA_QUEUE_DEPTH); 79 atomic_set(&hba->max_queue_depth, IBLOCK_HBA_QUEUE_DEPTH); 80 hba->hba_ptr = (void *) ib_host; 81 82 printk(KERN_INFO "CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 83 " Generic Target Core Stack %s\n", hba->hba_id, 84 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION); 85 86 printk(KERN_INFO "CORE_HBA[%d] - Attached iBlock HBA: %u to Generic" 87 " Target Core TCQ Depth: %d\n", hba->hba_id, 88 ib_host->iblock_host_id, atomic_read(&hba->max_queue_depth)); 89 90 return 0; 91 } 92 93 static void iblock_detach_hba(struct se_hba *hba) 94 { 95 struct iblock_hba *ib_host = hba->hba_ptr; 96 97 printk(KERN_INFO "CORE_HBA[%d] - Detached iBlock HBA: %u from Generic" 98 " Target Core\n", hba->hba_id, ib_host->iblock_host_id); 99 100 kfree(ib_host); 101 hba->hba_ptr = NULL; 102 } 103 104 static void *iblock_allocate_virtdevice(struct se_hba *hba, const char *name) 105 { 106 struct iblock_dev *ib_dev = NULL; 107 struct iblock_hba *ib_host = hba->hba_ptr; 108 109 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 110 if (!(ib_dev)) { 111 printk(KERN_ERR "Unable to allocate struct iblock_dev\n"); 112 return NULL; 113 } 114 ib_dev->ibd_host = ib_host; 115 116 printk(KERN_INFO "IBLOCK: Allocated ib_dev for %s\n", name); 117 118 return ib_dev; 119 } 120 121 static struct se_device *iblock_create_virtdevice( 122 struct se_hba *hba, 123 struct se_subsystem_dev *se_dev, 124 void *p) 125 { 126 struct iblock_dev *ib_dev = p; 127 struct se_device *dev; 128 struct se_dev_limits dev_limits; 129 struct block_device *bd = NULL; 130 struct request_queue *q; 131 struct queue_limits *limits; 132 u32 dev_flags = 0; 133 134 if (!(ib_dev)) { 135 printk(KERN_ERR "Unable to locate struct iblock_dev parameter\n"); 136 return 0; 137 } 138 memset(&dev_limits, 0, sizeof(struct se_dev_limits)); 139 /* 140 * These settings need to be made tunable.. 141 */ 142 ib_dev->ibd_bio_set = bioset_create(32, 64); 143 if (!(ib_dev->ibd_bio_set)) { 144 printk(KERN_ERR "IBLOCK: Unable to create bioset()\n"); 145 return 0; 146 } 147 printk(KERN_INFO "IBLOCK: Created bio_set()\n"); 148 /* 149 * iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path 150 * must already have been set in order for echo 1 > $HBA/$DEV/enable to run. 151 */ 152 printk(KERN_INFO "IBLOCK: Claiming struct block_device: %s\n", 153 ib_dev->ibd_udev_path); 154 155 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, 156 FMODE_WRITE|FMODE_READ|FMODE_EXCL, ib_dev); 157 if (!(bd)) 158 goto failed; 159 /* 160 * Setup the local scope queue_limits from struct request_queue->limits 161 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits. 162 */ 163 q = bdev_get_queue(bd); 164 limits = &dev_limits.limits; 165 limits->logical_block_size = bdev_logical_block_size(bd); 166 limits->max_hw_sectors = queue_max_hw_sectors(q); 167 limits->max_sectors = queue_max_sectors(q); 168 dev_limits.hw_queue_depth = IBLOCK_MAX_DEVICE_QUEUE_DEPTH; 169 dev_limits.queue_depth = IBLOCK_DEVICE_QUEUE_DEPTH; 170 171 ib_dev->ibd_major = MAJOR(bd->bd_dev); 172 ib_dev->ibd_minor = MINOR(bd->bd_dev); 173 ib_dev->ibd_bd = bd; 174 175 dev = transport_add_device_to_core_hba(hba, 176 &iblock_template, se_dev, dev_flags, (void *)ib_dev, 177 &dev_limits, "IBLOCK", IBLOCK_VERSION); 178 if (!(dev)) 179 goto failed; 180 181 ib_dev->ibd_depth = dev->queue_depth; 182 183 /* 184 * Check if the underlying struct block_device request_queue supports 185 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM 186 * in ATA and we need to set TPE=1 187 */ 188 if (blk_queue_discard(bdev_get_queue(bd))) { 189 struct request_queue *q = bdev_get_queue(bd); 190 191 DEV_ATTRIB(dev)->max_unmap_lba_count = 192 q->limits.max_discard_sectors; 193 /* 194 * Currently hardcoded to 1 in Linux/SCSI code.. 195 */ 196 DEV_ATTRIB(dev)->max_unmap_block_desc_count = 1; 197 DEV_ATTRIB(dev)->unmap_granularity = 198 q->limits.discard_granularity; 199 DEV_ATTRIB(dev)->unmap_granularity_alignment = 200 q->limits.discard_alignment; 201 202 printk(KERN_INFO "IBLOCK: BLOCK Discard support available," 203 " disabled by default\n"); 204 } 205 206 return dev; 207 208 failed: 209 if (ib_dev->ibd_bio_set) { 210 bioset_free(ib_dev->ibd_bio_set); 211 ib_dev->ibd_bio_set = NULL; 212 } 213 ib_dev->ibd_bd = NULL; 214 ib_dev->ibd_major = 0; 215 ib_dev->ibd_minor = 0; 216 return NULL; 217 } 218 219 static void iblock_free_device(void *p) 220 { 221 struct iblock_dev *ib_dev = p; 222 223 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 224 bioset_free(ib_dev->ibd_bio_set); 225 kfree(ib_dev); 226 } 227 228 static inline struct iblock_req *IBLOCK_REQ(struct se_task *task) 229 { 230 return container_of(task, struct iblock_req, ib_task); 231 } 232 233 static struct se_task * 234 iblock_alloc_task(struct se_cmd *cmd) 235 { 236 struct iblock_req *ib_req; 237 238 ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 239 if (!(ib_req)) { 240 printk(KERN_ERR "Unable to allocate memory for struct iblock_req\n"); 241 return NULL; 242 } 243 244 ib_req->ib_dev = SE_DEV(cmd)->dev_ptr; 245 atomic_set(&ib_req->ib_bio_cnt, 0); 246 return &ib_req->ib_task; 247 } 248 249 static unsigned long long iblock_emulate_read_cap_with_block_size( 250 struct se_device *dev, 251 struct block_device *bd, 252 struct request_queue *q) 253 { 254 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode), 255 bdev_logical_block_size(bd)) - 1); 256 u32 block_size = bdev_logical_block_size(bd); 257 258 if (block_size == DEV_ATTRIB(dev)->block_size) 259 return blocks_long; 260 261 switch (block_size) { 262 case 4096: 263 switch (DEV_ATTRIB(dev)->block_size) { 264 case 2048: 265 blocks_long <<= 1; 266 break; 267 case 1024: 268 blocks_long <<= 2; 269 break; 270 case 512: 271 blocks_long <<= 3; 272 default: 273 break; 274 } 275 break; 276 case 2048: 277 switch (DEV_ATTRIB(dev)->block_size) { 278 case 4096: 279 blocks_long >>= 1; 280 break; 281 case 1024: 282 blocks_long <<= 1; 283 break; 284 case 512: 285 blocks_long <<= 2; 286 break; 287 default: 288 break; 289 } 290 break; 291 case 1024: 292 switch (DEV_ATTRIB(dev)->block_size) { 293 case 4096: 294 blocks_long >>= 2; 295 break; 296 case 2048: 297 blocks_long >>= 1; 298 break; 299 case 512: 300 blocks_long <<= 1; 301 break; 302 default: 303 break; 304 } 305 break; 306 case 512: 307 switch (DEV_ATTRIB(dev)->block_size) { 308 case 4096: 309 blocks_long >>= 3; 310 break; 311 case 2048: 312 blocks_long >>= 2; 313 break; 314 case 1024: 315 blocks_long >>= 1; 316 break; 317 default: 318 break; 319 } 320 break; 321 default: 322 break; 323 } 324 325 return blocks_long; 326 } 327 328 /* 329 * Emulate SYCHRONIZE_CACHE_* 330 */ 331 static void iblock_emulate_sync_cache(struct se_task *task) 332 { 333 struct se_cmd *cmd = TASK_CMD(task); 334 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr; 335 int immed = (T_TASK(cmd)->t_task_cdb[1] & 0x2); 336 sector_t error_sector; 337 int ret; 338 339 /* 340 * If the Immediate bit is set, queue up the GOOD response 341 * for this SYNCHRONIZE_CACHE op 342 */ 343 if (immed) 344 transport_complete_sync_cache(cmd, 1); 345 346 /* 347 * blkdev_issue_flush() does not support a specifying a range, so 348 * we have to flush the entire cache. 349 */ 350 ret = blkdev_issue_flush(ib_dev->ibd_bd, GFP_KERNEL, &error_sector); 351 if (ret != 0) { 352 printk(KERN_ERR "IBLOCK: block_issue_flush() failed: %d " 353 " error_sector: %llu\n", ret, 354 (unsigned long long)error_sector); 355 } 356 357 if (!immed) 358 transport_complete_sync_cache(cmd, ret == 0); 359 } 360 361 /* 362 * Tell TCM Core that we are capable of WriteCache emulation for 363 * an underlying struct se_device. 364 */ 365 static int iblock_emulated_write_cache(struct se_device *dev) 366 { 367 return 1; 368 } 369 370 static int iblock_emulated_dpo(struct se_device *dev) 371 { 372 return 0; 373 } 374 375 /* 376 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs 377 * for TYPE_DISK. 378 */ 379 static int iblock_emulated_fua_write(struct se_device *dev) 380 { 381 return 1; 382 } 383 384 static int iblock_emulated_fua_read(struct se_device *dev) 385 { 386 return 0; 387 } 388 389 static int iblock_do_task(struct se_task *task) 390 { 391 struct se_device *dev = task->task_se_cmd->se_dev; 392 struct iblock_req *req = IBLOCK_REQ(task); 393 struct iblock_dev *ibd = (struct iblock_dev *)req->ib_dev; 394 struct request_queue *q = bdev_get_queue(ibd->ibd_bd); 395 struct bio *bio = req->ib_bio, *nbio = NULL; 396 int rw; 397 398 if (task->task_data_direction == DMA_TO_DEVICE) { 399 /* 400 * Force data to disk if we pretend to not have a volatile 401 * write cache, or the initiator set the Force Unit Access bit. 402 */ 403 if (DEV_ATTRIB(dev)->emulate_write_cache == 0 || 404 (DEV_ATTRIB(dev)->emulate_fua_write > 0 && 405 T_TASK(task->task_se_cmd)->t_tasks_fua)) 406 rw = WRITE_FUA; 407 else 408 rw = WRITE; 409 } else { 410 rw = READ; 411 } 412 413 while (bio) { 414 nbio = bio->bi_next; 415 bio->bi_next = NULL; 416 DEBUG_IBLOCK("Calling submit_bio() task: %p bio: %p" 417 " bio->bi_sector: %llu\n", task, bio, bio->bi_sector); 418 419 submit_bio(rw, bio); 420 bio = nbio; 421 } 422 423 if (q->unplug_fn) 424 q->unplug_fn(q); 425 return PYX_TRANSPORT_SENT_TO_TRANSPORT; 426 } 427 428 static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range) 429 { 430 struct iblock_dev *ibd = dev->dev_ptr; 431 struct block_device *bd = ibd->ibd_bd; 432 int barrier = 0; 433 434 return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier); 435 } 436 437 static void iblock_free_task(struct se_task *task) 438 { 439 struct iblock_req *req = IBLOCK_REQ(task); 440 struct bio *bio, *hbio = req->ib_bio; 441 /* 442 * We only release the bio(s) here if iblock_bio_done() has not called 443 * bio_put() -> iblock_bio_destructor(). 444 */ 445 while (hbio != NULL) { 446 bio = hbio; 447 hbio = hbio->bi_next; 448 bio->bi_next = NULL; 449 bio_put(bio); 450 } 451 452 kfree(req); 453 } 454 455 enum { 456 Opt_udev_path, Opt_force, Opt_err 457 }; 458 459 static match_table_t tokens = { 460 {Opt_udev_path, "udev_path=%s"}, 461 {Opt_force, "force=%d"}, 462 {Opt_err, NULL} 463 }; 464 465 static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba, 466 struct se_subsystem_dev *se_dev, 467 const char *page, ssize_t count) 468 { 469 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr; 470 char *orig, *ptr, *opts; 471 substring_t args[MAX_OPT_ARGS]; 472 int ret = 0, arg, token; 473 474 opts = kstrdup(page, GFP_KERNEL); 475 if (!opts) 476 return -ENOMEM; 477 478 orig = opts; 479 480 while ((ptr = strsep(&opts, ",")) != NULL) { 481 if (!*ptr) 482 continue; 483 484 token = match_token(ptr, tokens, args); 485 switch (token) { 486 case Opt_udev_path: 487 if (ib_dev->ibd_bd) { 488 printk(KERN_ERR "Unable to set udev_path= while" 489 " ib_dev->ibd_bd exists\n"); 490 ret = -EEXIST; 491 goto out; 492 } 493 494 ret = snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN, 495 "%s", match_strdup(&args[0])); 496 printk(KERN_INFO "IBLOCK: Referencing UDEV path: %s\n", 497 ib_dev->ibd_udev_path); 498 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 499 break; 500 case Opt_force: 501 match_int(args, &arg); 502 ib_dev->ibd_force = arg; 503 printk(KERN_INFO "IBLOCK: Set force=%d\n", 504 ib_dev->ibd_force); 505 break; 506 default: 507 break; 508 } 509 } 510 511 out: 512 kfree(orig); 513 return (!ret) ? count : ret; 514 } 515 516 static ssize_t iblock_check_configfs_dev_params( 517 struct se_hba *hba, 518 struct se_subsystem_dev *se_dev) 519 { 520 struct iblock_dev *ibd = se_dev->se_dev_su_ptr; 521 522 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) { 523 printk(KERN_ERR "Missing udev_path= parameters for IBLOCK\n"); 524 return -1; 525 } 526 527 return 0; 528 } 529 530 static ssize_t iblock_show_configfs_dev_params( 531 struct se_hba *hba, 532 struct se_subsystem_dev *se_dev, 533 char *b) 534 { 535 struct iblock_dev *ibd = se_dev->se_dev_su_ptr; 536 struct block_device *bd = ibd->ibd_bd; 537 char buf[BDEVNAME_SIZE]; 538 ssize_t bl = 0; 539 540 if (bd) 541 bl += sprintf(b + bl, "iBlock device: %s", 542 bdevname(bd, buf)); 543 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) { 544 bl += sprintf(b + bl, " UDEV PATH: %s\n", 545 ibd->ibd_udev_path); 546 } else 547 bl += sprintf(b + bl, "\n"); 548 549 bl += sprintf(b + bl, " "); 550 if (bd) { 551 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 552 ibd->ibd_major, ibd->ibd_minor, (!bd->bd_contains) ? 553 "" : (bd->bd_holder == (struct iblock_dev *)ibd) ? 554 "CLAIMED: IBLOCK" : "CLAIMED: OS"); 555 } else { 556 bl += sprintf(b + bl, "Major: %d Minor: %d\n", 557 ibd->ibd_major, ibd->ibd_minor); 558 } 559 560 return bl; 561 } 562 563 static void iblock_bio_destructor(struct bio *bio) 564 { 565 struct se_task *task = bio->bi_private; 566 struct iblock_dev *ib_dev = task->se_dev->dev_ptr; 567 568 bio_free(bio, ib_dev->ibd_bio_set); 569 } 570 571 static struct bio *iblock_get_bio( 572 struct se_task *task, 573 struct iblock_req *ib_req, 574 struct iblock_dev *ib_dev, 575 int *ret, 576 sector_t lba, 577 u32 sg_num) 578 { 579 struct bio *bio; 580 581 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set); 582 if (!(bio)) { 583 printk(KERN_ERR "Unable to allocate memory for bio\n"); 584 *ret = PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES; 585 return NULL; 586 } 587 588 DEBUG_IBLOCK("Allocated bio: %p task_sg_num: %u using ibd_bio_set:" 589 " %p\n", bio, task->task_sg_num, ib_dev->ibd_bio_set); 590 DEBUG_IBLOCK("Allocated bio: %p task_size: %u\n", bio, task->task_size); 591 592 bio->bi_bdev = ib_dev->ibd_bd; 593 bio->bi_private = (void *) task; 594 bio->bi_destructor = iblock_bio_destructor; 595 bio->bi_end_io = &iblock_bio_done; 596 bio->bi_sector = lba; 597 atomic_inc(&ib_req->ib_bio_cnt); 598 599 DEBUG_IBLOCK("Set bio->bi_sector: %llu\n", bio->bi_sector); 600 DEBUG_IBLOCK("Set ib_req->ib_bio_cnt: %d\n", 601 atomic_read(&ib_req->ib_bio_cnt)); 602 return bio; 603 } 604 605 static int iblock_map_task_SG(struct se_task *task) 606 { 607 struct se_cmd *cmd = task->task_se_cmd; 608 struct se_device *dev = SE_DEV(cmd); 609 struct iblock_dev *ib_dev = task->se_dev->dev_ptr; 610 struct iblock_req *ib_req = IBLOCK_REQ(task); 611 struct bio *bio = NULL, *hbio = NULL, *tbio = NULL; 612 struct scatterlist *sg; 613 int ret = 0; 614 u32 i, sg_num = task->task_sg_num; 615 sector_t block_lba; 616 /* 617 * Do starting conversion up from non 512-byte blocksize with 618 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO. 619 */ 620 if (DEV_ATTRIB(dev)->block_size == 4096) 621 block_lba = (task->task_lba << 3); 622 else if (DEV_ATTRIB(dev)->block_size == 2048) 623 block_lba = (task->task_lba << 2); 624 else if (DEV_ATTRIB(dev)->block_size == 1024) 625 block_lba = (task->task_lba << 1); 626 else if (DEV_ATTRIB(dev)->block_size == 512) 627 block_lba = task->task_lba; 628 else { 629 printk(KERN_ERR "Unsupported SCSI -> BLOCK LBA conversion:" 630 " %u\n", DEV_ATTRIB(dev)->block_size); 631 return PYX_TRANSPORT_LU_COMM_FAILURE; 632 } 633 634 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, block_lba, sg_num); 635 if (!(bio)) 636 return ret; 637 638 ib_req->ib_bio = bio; 639 hbio = tbio = bio; 640 /* 641 * Use fs/bio.c:bio_add_pages() to setup the bio_vec maplist 642 * from TCM struct se_mem -> task->task_sg -> struct scatterlist memory. 643 */ 644 for_each_sg(task->task_sg, sg, task->task_sg_num, i) { 645 DEBUG_IBLOCK("task: %p bio: %p Calling bio_add_page(): page:" 646 " %p len: %u offset: %u\n", task, bio, sg_page(sg), 647 sg->length, sg->offset); 648 again: 649 ret = bio_add_page(bio, sg_page(sg), sg->length, sg->offset); 650 if (ret != sg->length) { 651 652 DEBUG_IBLOCK("*** Set bio->bi_sector: %llu\n", 653 bio->bi_sector); 654 DEBUG_IBLOCK("** task->task_size: %u\n", 655 task->task_size); 656 DEBUG_IBLOCK("*** bio->bi_max_vecs: %u\n", 657 bio->bi_max_vecs); 658 DEBUG_IBLOCK("*** bio->bi_vcnt: %u\n", 659 bio->bi_vcnt); 660 661 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, 662 block_lba, sg_num); 663 if (!(bio)) 664 goto fail; 665 666 tbio = tbio->bi_next = bio; 667 DEBUG_IBLOCK("-----------------> Added +1 bio: %p to" 668 " list, Going to again\n", bio); 669 goto again; 670 } 671 /* Always in 512 byte units for Linux/Block */ 672 block_lba += sg->length >> IBLOCK_LBA_SHIFT; 673 sg_num--; 674 DEBUG_IBLOCK("task: %p bio-add_page() passed!, decremented" 675 " sg_num to %u\n", task, sg_num); 676 DEBUG_IBLOCK("task: %p bio_add_page() passed!, increased lba" 677 " to %llu\n", task, block_lba); 678 DEBUG_IBLOCK("task: %p bio_add_page() passed!, bio->bi_vcnt:" 679 " %u\n", task, bio->bi_vcnt); 680 } 681 682 return 0; 683 fail: 684 while (hbio) { 685 bio = hbio; 686 hbio = hbio->bi_next; 687 bio->bi_next = NULL; 688 bio_put(bio); 689 } 690 return ret; 691 } 692 693 static unsigned char *iblock_get_cdb(struct se_task *task) 694 { 695 return IBLOCK_REQ(task)->ib_scsi_cdb; 696 } 697 698 static u32 iblock_get_device_rev(struct se_device *dev) 699 { 700 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */ 701 } 702 703 static u32 iblock_get_device_type(struct se_device *dev) 704 { 705 return TYPE_DISK; 706 } 707 708 static sector_t iblock_get_blocks(struct se_device *dev) 709 { 710 struct iblock_dev *ibd = dev->dev_ptr; 711 struct block_device *bd = ibd->ibd_bd; 712 struct request_queue *q = bdev_get_queue(bd); 713 714 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 715 } 716 717 static void iblock_bio_done(struct bio *bio, int err) 718 { 719 struct se_task *task = bio->bi_private; 720 struct iblock_req *ibr = IBLOCK_REQ(task); 721 /* 722 * Set -EIO if !BIO_UPTODATE and the passed is still err=0 723 */ 724 if (!(test_bit(BIO_UPTODATE, &bio->bi_flags)) && !(err)) 725 err = -EIO; 726 727 if (err != 0) { 728 printk(KERN_ERR "test_bit(BIO_UPTODATE) failed for bio: %p," 729 " err: %d\n", bio, err); 730 /* 731 * Bump the ib_bio_err_cnt and release bio. 732 */ 733 atomic_inc(&ibr->ib_bio_err_cnt); 734 smp_mb__after_atomic_inc(); 735 bio_put(bio); 736 /* 737 * Wait to complete the task until the last bio as completed. 738 */ 739 if (!(atomic_dec_and_test(&ibr->ib_bio_cnt))) 740 return; 741 742 ibr->ib_bio = NULL; 743 transport_complete_task(task, 0); 744 return; 745 } 746 DEBUG_IBLOCK("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n", 747 task, bio, task->task_lba, bio->bi_sector, err); 748 /* 749 * bio_put() will call iblock_bio_destructor() to release the bio back 750 * to ibr->ib_bio_set. 751 */ 752 bio_put(bio); 753 /* 754 * Wait to complete the task until the last bio as completed. 755 */ 756 if (!(atomic_dec_and_test(&ibr->ib_bio_cnt))) 757 return; 758 /* 759 * Return GOOD status for task if zero ib_bio_err_cnt exists. 760 */ 761 ibr->ib_bio = NULL; 762 transport_complete_task(task, (!atomic_read(&ibr->ib_bio_err_cnt))); 763 } 764 765 static struct se_subsystem_api iblock_template = { 766 .name = "iblock", 767 .owner = THIS_MODULE, 768 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, 769 .map_task_SG = iblock_map_task_SG, 770 .attach_hba = iblock_attach_hba, 771 .detach_hba = iblock_detach_hba, 772 .allocate_virtdevice = iblock_allocate_virtdevice, 773 .create_virtdevice = iblock_create_virtdevice, 774 .free_device = iblock_free_device, 775 .dpo_emulated = iblock_emulated_dpo, 776 .fua_write_emulated = iblock_emulated_fua_write, 777 .fua_read_emulated = iblock_emulated_fua_read, 778 .write_cache_emulated = iblock_emulated_write_cache, 779 .alloc_task = iblock_alloc_task, 780 .do_task = iblock_do_task, 781 .do_discard = iblock_do_discard, 782 .do_sync_cache = iblock_emulate_sync_cache, 783 .free_task = iblock_free_task, 784 .check_configfs_dev_params = iblock_check_configfs_dev_params, 785 .set_configfs_dev_params = iblock_set_configfs_dev_params, 786 .show_configfs_dev_params = iblock_show_configfs_dev_params, 787 .get_cdb = iblock_get_cdb, 788 .get_device_rev = iblock_get_device_rev, 789 .get_device_type = iblock_get_device_type, 790 .get_blocks = iblock_get_blocks, 791 }; 792 793 static int __init iblock_module_init(void) 794 { 795 return transport_subsystem_register(&iblock_template); 796 } 797 798 static void iblock_module_exit(void) 799 { 800 transport_subsystem_release(&iblock_template); 801 } 802 803 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 804 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 805 MODULE_LICENSE("GPL"); 806 807 module_init(iblock_module_init); 808 module_exit(iblock_module_exit); 809