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 #if 0 51 #define DEBUG_IBLOCK(x...) printk(x) 52 #else 53 #define DEBUG_IBLOCK(x...) 54 #endif 55 56 static struct se_subsystem_api iblock_template; 57 58 static void iblock_bio_done(struct bio *, int); 59 60 /* iblock_attach_hba(): (Part of se_subsystem_api_t template) 61 * 62 * 63 */ 64 static int iblock_attach_hba(struct se_hba *hba, u32 host_id) 65 { 66 struct iblock_hba *ib_host; 67 68 ib_host = kzalloc(sizeof(struct iblock_hba), GFP_KERNEL); 69 if (!(ib_host)) { 70 printk(KERN_ERR "Unable to allocate memory for" 71 " struct iblock_hba\n"); 72 return -ENOMEM; 73 } 74 75 ib_host->iblock_host_id = host_id; 76 77 atomic_set(&hba->left_queue_depth, IBLOCK_HBA_QUEUE_DEPTH); 78 atomic_set(&hba->max_queue_depth, IBLOCK_HBA_QUEUE_DEPTH); 79 hba->hba_ptr = (void *) ib_host; 80 81 printk(KERN_INFO "CORE_HBA[%d] - TCM iBlock HBA Driver %s on" 82 " Generic Target Core Stack %s\n", hba->hba_id, 83 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION); 84 85 printk(KERN_INFO "CORE_HBA[%d] - Attached iBlock HBA: %u to Generic" 86 " Target Core TCQ Depth: %d\n", hba->hba_id, 87 ib_host->iblock_host_id, atomic_read(&hba->max_queue_depth)); 88 89 return 0; 90 } 91 92 static void iblock_detach_hba(struct se_hba *hba) 93 { 94 struct iblock_hba *ib_host = hba->hba_ptr; 95 96 printk(KERN_INFO "CORE_HBA[%d] - Detached iBlock HBA: %u from Generic" 97 " Target Core\n", hba->hba_id, ib_host->iblock_host_id); 98 99 kfree(ib_host); 100 hba->hba_ptr = NULL; 101 } 102 103 static void *iblock_allocate_virtdevice(struct se_hba *hba, const char *name) 104 { 105 struct iblock_dev *ib_dev = NULL; 106 struct iblock_hba *ib_host = hba->hba_ptr; 107 108 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL); 109 if (!(ib_dev)) { 110 printk(KERN_ERR "Unable to allocate struct iblock_dev\n"); 111 return NULL; 112 } 113 ib_dev->ibd_host = ib_host; 114 115 printk(KERN_INFO "IBLOCK: Allocated ib_dev for %s\n", name); 116 117 return ib_dev; 118 } 119 120 static struct se_device *iblock_create_virtdevice( 121 struct se_hba *hba, 122 struct se_subsystem_dev *se_dev, 123 void *p) 124 { 125 struct iblock_dev *ib_dev = p; 126 struct se_device *dev; 127 struct se_dev_limits dev_limits; 128 struct block_device *bd = NULL; 129 struct request_queue *q; 130 struct queue_limits *limits; 131 u32 dev_flags = 0; 132 133 if (!(ib_dev)) { 134 printk(KERN_ERR "Unable to locate struct iblock_dev parameter\n"); 135 return 0; 136 } 137 memset(&dev_limits, 0, sizeof(struct se_dev_limits)); 138 /* 139 * These settings need to be made tunable.. 140 */ 141 ib_dev->ibd_bio_set = bioset_create(32, 64); 142 if (!(ib_dev->ibd_bio_set)) { 143 printk(KERN_ERR "IBLOCK: Unable to create bioset()\n"); 144 return 0; 145 } 146 printk(KERN_INFO "IBLOCK: Created bio_set()\n"); 147 /* 148 * iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path 149 * must already have been set in order for echo 1 > $HBA/$DEV/enable to run. 150 */ 151 printk(KERN_INFO "IBLOCK: Claiming struct block_device: %s\n", 152 ib_dev->ibd_udev_path); 153 154 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, 155 FMODE_WRITE|FMODE_READ|FMODE_EXCL, ib_dev); 156 if (IS_ERR(bd)) 157 goto failed; 158 /* 159 * Setup the local scope queue_limits from struct request_queue->limits 160 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits. 161 */ 162 q = bdev_get_queue(bd); 163 limits = &dev_limits.limits; 164 limits->logical_block_size = bdev_logical_block_size(bd); 165 limits->max_hw_sectors = queue_max_hw_sectors(q); 166 limits->max_sectors = queue_max_sectors(q); 167 dev_limits.hw_queue_depth = IBLOCK_MAX_DEVICE_QUEUE_DEPTH; 168 dev_limits.queue_depth = IBLOCK_DEVICE_QUEUE_DEPTH; 169 170 ib_dev->ibd_major = MAJOR(bd->bd_dev); 171 ib_dev->ibd_minor = MINOR(bd->bd_dev); 172 ib_dev->ibd_bd = bd; 173 174 dev = transport_add_device_to_core_hba(hba, 175 &iblock_template, se_dev, dev_flags, (void *)ib_dev, 176 &dev_limits, "IBLOCK", IBLOCK_VERSION); 177 if (!(dev)) 178 goto failed; 179 180 ib_dev->ibd_depth = dev->queue_depth; 181 182 /* 183 * Check if the underlying struct block_device request_queue supports 184 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM 185 * in ATA and we need to set TPE=1 186 */ 187 if (blk_queue_discard(bdev_get_queue(bd))) { 188 struct request_queue *q = bdev_get_queue(bd); 189 190 DEV_ATTRIB(dev)->max_unmap_lba_count = 191 q->limits.max_discard_sectors; 192 /* 193 * Currently hardcoded to 1 in Linux/SCSI code.. 194 */ 195 DEV_ATTRIB(dev)->max_unmap_block_desc_count = 1; 196 DEV_ATTRIB(dev)->unmap_granularity = 197 q->limits.discard_granularity; 198 DEV_ATTRIB(dev)->unmap_granularity_alignment = 199 q->limits.discard_alignment; 200 201 printk(KERN_INFO "IBLOCK: BLOCK Discard support available," 202 " disabled by default\n"); 203 } 204 205 return dev; 206 207 failed: 208 if (ib_dev->ibd_bio_set) { 209 bioset_free(ib_dev->ibd_bio_set); 210 ib_dev->ibd_bio_set = NULL; 211 } 212 ib_dev->ibd_bd = NULL; 213 ib_dev->ibd_major = 0; 214 ib_dev->ibd_minor = 0; 215 return NULL; 216 } 217 218 static void iblock_free_device(void *p) 219 { 220 struct iblock_dev *ib_dev = p; 221 222 if (ib_dev->ibd_bd != NULL) 223 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 224 if (ib_dev->ibd_bio_set != NULL) 225 bioset_free(ib_dev->ibd_bio_set); 226 kfree(ib_dev); 227 } 228 229 static inline struct iblock_req *IBLOCK_REQ(struct se_task *task) 230 { 231 return container_of(task, struct iblock_req, ib_task); 232 } 233 234 static struct se_task * 235 iblock_alloc_task(struct se_cmd *cmd) 236 { 237 struct iblock_req *ib_req; 238 239 ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 240 if (!(ib_req)) { 241 printk(KERN_ERR "Unable to allocate memory for struct iblock_req\n"); 242 return NULL; 243 } 244 245 ib_req->ib_dev = SE_DEV(cmd)->dev_ptr; 246 atomic_set(&ib_req->ib_bio_cnt, 0); 247 return &ib_req->ib_task; 248 } 249 250 static unsigned long long iblock_emulate_read_cap_with_block_size( 251 struct se_device *dev, 252 struct block_device *bd, 253 struct request_queue *q) 254 { 255 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode), 256 bdev_logical_block_size(bd)) - 1); 257 u32 block_size = bdev_logical_block_size(bd); 258 259 if (block_size == DEV_ATTRIB(dev)->block_size) 260 return blocks_long; 261 262 switch (block_size) { 263 case 4096: 264 switch (DEV_ATTRIB(dev)->block_size) { 265 case 2048: 266 blocks_long <<= 1; 267 break; 268 case 1024: 269 blocks_long <<= 2; 270 break; 271 case 512: 272 blocks_long <<= 3; 273 default: 274 break; 275 } 276 break; 277 case 2048: 278 switch (DEV_ATTRIB(dev)->block_size) { 279 case 4096: 280 blocks_long >>= 1; 281 break; 282 case 1024: 283 blocks_long <<= 1; 284 break; 285 case 512: 286 blocks_long <<= 2; 287 break; 288 default: 289 break; 290 } 291 break; 292 case 1024: 293 switch (DEV_ATTRIB(dev)->block_size) { 294 case 4096: 295 blocks_long >>= 2; 296 break; 297 case 2048: 298 blocks_long >>= 1; 299 break; 300 case 512: 301 blocks_long <<= 1; 302 break; 303 default: 304 break; 305 } 306 break; 307 case 512: 308 switch (DEV_ATTRIB(dev)->block_size) { 309 case 4096: 310 blocks_long >>= 3; 311 break; 312 case 2048: 313 blocks_long >>= 2; 314 break; 315 case 1024: 316 blocks_long >>= 1; 317 break; 318 default: 319 break; 320 } 321 break; 322 default: 323 break; 324 } 325 326 return blocks_long; 327 } 328 329 /* 330 * Emulate SYCHRONIZE_CACHE_* 331 */ 332 static void iblock_emulate_sync_cache(struct se_task *task) 333 { 334 struct se_cmd *cmd = TASK_CMD(task); 335 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr; 336 int immed = (T_TASK(cmd)->t_task_cdb[1] & 0x2); 337 sector_t error_sector; 338 int ret; 339 340 /* 341 * If the Immediate bit is set, queue up the GOOD response 342 * for this SYNCHRONIZE_CACHE op 343 */ 344 if (immed) 345 transport_complete_sync_cache(cmd, 1); 346 347 /* 348 * blkdev_issue_flush() does not support a specifying a range, so 349 * we have to flush the entire cache. 350 */ 351 ret = blkdev_issue_flush(ib_dev->ibd_bd, GFP_KERNEL, &error_sector); 352 if (ret != 0) { 353 printk(KERN_ERR "IBLOCK: block_issue_flush() failed: %d " 354 " error_sector: %llu\n", ret, 355 (unsigned long long)error_sector); 356 } 357 358 if (!immed) 359 transport_complete_sync_cache(cmd, ret == 0); 360 } 361 362 /* 363 * Tell TCM Core that we are capable of WriteCache emulation for 364 * an underlying struct se_device. 365 */ 366 static int iblock_emulated_write_cache(struct se_device *dev) 367 { 368 return 1; 369 } 370 371 static int iblock_emulated_dpo(struct se_device *dev) 372 { 373 return 0; 374 } 375 376 /* 377 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs 378 * for TYPE_DISK. 379 */ 380 static int iblock_emulated_fua_write(struct se_device *dev) 381 { 382 return 1; 383 } 384 385 static int iblock_emulated_fua_read(struct se_device *dev) 386 { 387 return 0; 388 } 389 390 static int iblock_do_task(struct se_task *task) 391 { 392 struct se_device *dev = task->task_se_cmd->se_dev; 393 struct iblock_req *req = IBLOCK_REQ(task); 394 struct iblock_dev *ibd = (struct iblock_dev *)req->ib_dev; 395 struct request_queue *q = bdev_get_queue(ibd->ibd_bd); 396 struct bio *bio = req->ib_bio, *nbio = NULL; 397 int rw; 398 399 if (task->task_data_direction == DMA_TO_DEVICE) { 400 /* 401 * Force data to disk if we pretend to not have a volatile 402 * write cache, or the initiator set the Force Unit Access bit. 403 */ 404 if (DEV_ATTRIB(dev)->emulate_write_cache == 0 || 405 (DEV_ATTRIB(dev)->emulate_fua_write > 0 && 406 T_TASK(task->task_se_cmd)->t_tasks_fua)) 407 rw = WRITE_FUA; 408 else 409 rw = WRITE; 410 } else { 411 rw = READ; 412 } 413 414 while (bio) { 415 nbio = bio->bi_next; 416 bio->bi_next = NULL; 417 DEBUG_IBLOCK("Calling submit_bio() task: %p bio: %p" 418 " bio->bi_sector: %llu\n", task, bio, bio->bi_sector); 419 420 submit_bio(rw, bio); 421 bio = nbio; 422 } 423 424 if (q->unplug_fn) 425 q->unplug_fn(q); 426 return PYX_TRANSPORT_SENT_TO_TRANSPORT; 427 } 428 429 static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range) 430 { 431 struct iblock_dev *ibd = dev->dev_ptr; 432 struct block_device *bd = ibd->ibd_bd; 433 int barrier = 0; 434 435 return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier); 436 } 437 438 static void iblock_free_task(struct se_task *task) 439 { 440 struct iblock_req *req = IBLOCK_REQ(task); 441 struct bio *bio, *hbio = req->ib_bio; 442 /* 443 * We only release the bio(s) here if iblock_bio_done() has not called 444 * bio_put() -> iblock_bio_destructor(). 445 */ 446 while (hbio != NULL) { 447 bio = hbio; 448 hbio = hbio->bi_next; 449 bio->bi_next = NULL; 450 bio_put(bio); 451 } 452 453 kfree(req); 454 } 455 456 enum { 457 Opt_udev_path, Opt_force, Opt_err 458 }; 459 460 static match_table_t tokens = { 461 {Opt_udev_path, "udev_path=%s"}, 462 {Opt_force, "force=%d"}, 463 {Opt_err, NULL} 464 }; 465 466 static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba, 467 struct se_subsystem_dev *se_dev, 468 const char *page, ssize_t count) 469 { 470 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr; 471 char *orig, *ptr, *opts; 472 substring_t args[MAX_OPT_ARGS]; 473 int ret = 0, arg, token; 474 475 opts = kstrdup(page, GFP_KERNEL); 476 if (!opts) 477 return -ENOMEM; 478 479 orig = opts; 480 481 while ((ptr = strsep(&opts, ",")) != NULL) { 482 if (!*ptr) 483 continue; 484 485 token = match_token(ptr, tokens, args); 486 switch (token) { 487 case Opt_udev_path: 488 if (ib_dev->ibd_bd) { 489 printk(KERN_ERR "Unable to set udev_path= while" 490 " ib_dev->ibd_bd exists\n"); 491 ret = -EEXIST; 492 goto out; 493 } 494 495 ret = snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN, 496 "%s", match_strdup(&args[0])); 497 printk(KERN_INFO "IBLOCK: Referencing UDEV path: %s\n", 498 ib_dev->ibd_udev_path); 499 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 500 break; 501 case Opt_force: 502 match_int(args, &arg); 503 ib_dev->ibd_force = arg; 504 printk(KERN_INFO "IBLOCK: Set force=%d\n", 505 ib_dev->ibd_force); 506 break; 507 default: 508 break; 509 } 510 } 511 512 out: 513 kfree(orig); 514 return (!ret) ? count : ret; 515 } 516 517 static ssize_t iblock_check_configfs_dev_params( 518 struct se_hba *hba, 519 struct se_subsystem_dev *se_dev) 520 { 521 struct iblock_dev *ibd = se_dev->se_dev_su_ptr; 522 523 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) { 524 printk(KERN_ERR "Missing udev_path= parameters for IBLOCK\n"); 525 return -1; 526 } 527 528 return 0; 529 } 530 531 static ssize_t iblock_show_configfs_dev_params( 532 struct se_hba *hba, 533 struct se_subsystem_dev *se_dev, 534 char *b) 535 { 536 struct iblock_dev *ibd = se_dev->se_dev_su_ptr; 537 struct block_device *bd = ibd->ibd_bd; 538 char buf[BDEVNAME_SIZE]; 539 ssize_t bl = 0; 540 541 if (bd) 542 bl += sprintf(b + bl, "iBlock device: %s", 543 bdevname(bd, buf)); 544 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) { 545 bl += sprintf(b + bl, " UDEV PATH: %s\n", 546 ibd->ibd_udev_path); 547 } else 548 bl += sprintf(b + bl, "\n"); 549 550 bl += sprintf(b + bl, " "); 551 if (bd) { 552 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 553 ibd->ibd_major, ibd->ibd_minor, (!bd->bd_contains) ? 554 "" : (bd->bd_holder == (struct iblock_dev *)ibd) ? 555 "CLAIMED: IBLOCK" : "CLAIMED: OS"); 556 } else { 557 bl += sprintf(b + bl, "Major: %d Minor: %d\n", 558 ibd->ibd_major, ibd->ibd_minor); 559 } 560 561 return bl; 562 } 563 564 static void iblock_bio_destructor(struct bio *bio) 565 { 566 struct se_task *task = bio->bi_private; 567 struct iblock_dev *ib_dev = task->se_dev->dev_ptr; 568 569 bio_free(bio, ib_dev->ibd_bio_set); 570 } 571 572 static struct bio *iblock_get_bio( 573 struct se_task *task, 574 struct iblock_req *ib_req, 575 struct iblock_dev *ib_dev, 576 int *ret, 577 sector_t lba, 578 u32 sg_num) 579 { 580 struct bio *bio; 581 582 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set); 583 if (!(bio)) { 584 printk(KERN_ERR "Unable to allocate memory for bio\n"); 585 *ret = PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES; 586 return NULL; 587 } 588 589 DEBUG_IBLOCK("Allocated bio: %p task_sg_num: %u using ibd_bio_set:" 590 " %p\n", bio, task->task_sg_num, ib_dev->ibd_bio_set); 591 DEBUG_IBLOCK("Allocated bio: %p task_size: %u\n", bio, task->task_size); 592 593 bio->bi_bdev = ib_dev->ibd_bd; 594 bio->bi_private = (void *) task; 595 bio->bi_destructor = iblock_bio_destructor; 596 bio->bi_end_io = &iblock_bio_done; 597 bio->bi_sector = lba; 598 atomic_inc(&ib_req->ib_bio_cnt); 599 600 DEBUG_IBLOCK("Set bio->bi_sector: %llu\n", bio->bi_sector); 601 DEBUG_IBLOCK("Set ib_req->ib_bio_cnt: %d\n", 602 atomic_read(&ib_req->ib_bio_cnt)); 603 return bio; 604 } 605 606 static int iblock_map_task_SG(struct se_task *task) 607 { 608 struct se_cmd *cmd = task->task_se_cmd; 609 struct se_device *dev = SE_DEV(cmd); 610 struct iblock_dev *ib_dev = task->se_dev->dev_ptr; 611 struct iblock_req *ib_req = IBLOCK_REQ(task); 612 struct bio *bio = NULL, *hbio = NULL, *tbio = NULL; 613 struct scatterlist *sg; 614 int ret = 0; 615 u32 i, sg_num = task->task_sg_num; 616 sector_t block_lba; 617 /* 618 * Do starting conversion up from non 512-byte blocksize with 619 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO. 620 */ 621 if (DEV_ATTRIB(dev)->block_size == 4096) 622 block_lba = (task->task_lba << 3); 623 else if (DEV_ATTRIB(dev)->block_size == 2048) 624 block_lba = (task->task_lba << 2); 625 else if (DEV_ATTRIB(dev)->block_size == 1024) 626 block_lba = (task->task_lba << 1); 627 else if (DEV_ATTRIB(dev)->block_size == 512) 628 block_lba = task->task_lba; 629 else { 630 printk(KERN_ERR "Unsupported SCSI -> BLOCK LBA conversion:" 631 " %u\n", DEV_ATTRIB(dev)->block_size); 632 return PYX_TRANSPORT_LU_COMM_FAILURE; 633 } 634 635 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, block_lba, sg_num); 636 if (!(bio)) 637 return ret; 638 639 ib_req->ib_bio = bio; 640 hbio = tbio = bio; 641 /* 642 * Use fs/bio.c:bio_add_pages() to setup the bio_vec maplist 643 * from TCM struct se_mem -> task->task_sg -> struct scatterlist memory. 644 */ 645 for_each_sg(task->task_sg, sg, task->task_sg_num, i) { 646 DEBUG_IBLOCK("task: %p bio: %p Calling bio_add_page(): page:" 647 " %p len: %u offset: %u\n", task, bio, sg_page(sg), 648 sg->length, sg->offset); 649 again: 650 ret = bio_add_page(bio, sg_page(sg), sg->length, sg->offset); 651 if (ret != sg->length) { 652 653 DEBUG_IBLOCK("*** Set bio->bi_sector: %llu\n", 654 bio->bi_sector); 655 DEBUG_IBLOCK("** task->task_size: %u\n", 656 task->task_size); 657 DEBUG_IBLOCK("*** bio->bi_max_vecs: %u\n", 658 bio->bi_max_vecs); 659 DEBUG_IBLOCK("*** bio->bi_vcnt: %u\n", 660 bio->bi_vcnt); 661 662 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, 663 block_lba, sg_num); 664 if (!(bio)) 665 goto fail; 666 667 tbio = tbio->bi_next = bio; 668 DEBUG_IBLOCK("-----------------> Added +1 bio: %p to" 669 " list, Going to again\n", bio); 670 goto again; 671 } 672 /* Always in 512 byte units for Linux/Block */ 673 block_lba += sg->length >> IBLOCK_LBA_SHIFT; 674 sg_num--; 675 DEBUG_IBLOCK("task: %p bio-add_page() passed!, decremented" 676 " sg_num to %u\n", task, sg_num); 677 DEBUG_IBLOCK("task: %p bio_add_page() passed!, increased lba" 678 " to %llu\n", task, block_lba); 679 DEBUG_IBLOCK("task: %p bio_add_page() passed!, bio->bi_vcnt:" 680 " %u\n", task, bio->bi_vcnt); 681 } 682 683 return 0; 684 fail: 685 while (hbio) { 686 bio = hbio; 687 hbio = hbio->bi_next; 688 bio->bi_next = NULL; 689 bio_put(bio); 690 } 691 return ret; 692 } 693 694 static unsigned char *iblock_get_cdb(struct se_task *task) 695 { 696 return IBLOCK_REQ(task)->ib_scsi_cdb; 697 } 698 699 static u32 iblock_get_device_rev(struct se_device *dev) 700 { 701 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */ 702 } 703 704 static u32 iblock_get_device_type(struct se_device *dev) 705 { 706 return TYPE_DISK; 707 } 708 709 static sector_t iblock_get_blocks(struct se_device *dev) 710 { 711 struct iblock_dev *ibd = dev->dev_ptr; 712 struct block_device *bd = ibd->ibd_bd; 713 struct request_queue *q = bdev_get_queue(bd); 714 715 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 716 } 717 718 static void iblock_bio_done(struct bio *bio, int err) 719 { 720 struct se_task *task = bio->bi_private; 721 struct iblock_req *ibr = IBLOCK_REQ(task); 722 /* 723 * Set -EIO if !BIO_UPTODATE and the passed is still err=0 724 */ 725 if (!(test_bit(BIO_UPTODATE, &bio->bi_flags)) && !(err)) 726 err = -EIO; 727 728 if (err != 0) { 729 printk(KERN_ERR "test_bit(BIO_UPTODATE) failed for bio: %p," 730 " err: %d\n", bio, err); 731 /* 732 * Bump the ib_bio_err_cnt and release bio. 733 */ 734 atomic_inc(&ibr->ib_bio_err_cnt); 735 smp_mb__after_atomic_inc(); 736 bio_put(bio); 737 /* 738 * Wait to complete the task until the last bio as completed. 739 */ 740 if (!(atomic_dec_and_test(&ibr->ib_bio_cnt))) 741 return; 742 743 ibr->ib_bio = NULL; 744 transport_complete_task(task, 0); 745 return; 746 } 747 DEBUG_IBLOCK("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n", 748 task, bio, task->task_lba, bio->bi_sector, err); 749 /* 750 * bio_put() will call iblock_bio_destructor() to release the bio back 751 * to ibr->ib_bio_set. 752 */ 753 bio_put(bio); 754 /* 755 * Wait to complete the task until the last bio as completed. 756 */ 757 if (!(atomic_dec_and_test(&ibr->ib_bio_cnt))) 758 return; 759 /* 760 * Return GOOD status for task if zero ib_bio_err_cnt exists. 761 */ 762 ibr->ib_bio = NULL; 763 transport_complete_task(task, (!atomic_read(&ibr->ib_bio_err_cnt))); 764 } 765 766 static struct se_subsystem_api iblock_template = { 767 .name = "iblock", 768 .owner = THIS_MODULE, 769 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, 770 .map_task_SG = iblock_map_task_SG, 771 .attach_hba = iblock_attach_hba, 772 .detach_hba = iblock_detach_hba, 773 .allocate_virtdevice = iblock_allocate_virtdevice, 774 .create_virtdevice = iblock_create_virtdevice, 775 .free_device = iblock_free_device, 776 .dpo_emulated = iblock_emulated_dpo, 777 .fua_write_emulated = iblock_emulated_fua_write, 778 .fua_read_emulated = iblock_emulated_fua_read, 779 .write_cache_emulated = iblock_emulated_write_cache, 780 .alloc_task = iblock_alloc_task, 781 .do_task = iblock_do_task, 782 .do_discard = iblock_do_discard, 783 .do_sync_cache = iblock_emulate_sync_cache, 784 .free_task = iblock_free_task, 785 .check_configfs_dev_params = iblock_check_configfs_dev_params, 786 .set_configfs_dev_params = iblock_set_configfs_dev_params, 787 .show_configfs_dev_params = iblock_show_configfs_dev_params, 788 .get_cdb = iblock_get_cdb, 789 .get_device_rev = iblock_get_device_rev, 790 .get_device_type = iblock_get_device_type, 791 .get_blocks = iblock_get_blocks, 792 }; 793 794 static int __init iblock_module_init(void) 795 { 796 return transport_subsystem_register(&iblock_template); 797 } 798 799 static void iblock_module_exit(void) 800 { 801 transport_subsystem_release(&iblock_template); 802 } 803 804 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 805 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 806 MODULE_LICENSE("GPL"); 807 808 module_init(iblock_module_init); 809 module_exit(iblock_module_exit); 810