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 (IS_ERR(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 if (ib_dev->ibd_bd != NULL) 224 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL); 225 if (ib_dev->ibd_bio_set != NULL) 226 bioset_free(ib_dev->ibd_bio_set); 227 kfree(ib_dev); 228 } 229 230 static inline struct iblock_req *IBLOCK_REQ(struct se_task *task) 231 { 232 return container_of(task, struct iblock_req, ib_task); 233 } 234 235 static struct se_task * 236 iblock_alloc_task(struct se_cmd *cmd) 237 { 238 struct iblock_req *ib_req; 239 240 ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); 241 if (!(ib_req)) { 242 printk(KERN_ERR "Unable to allocate memory for struct iblock_req\n"); 243 return NULL; 244 } 245 246 ib_req->ib_dev = SE_DEV(cmd)->dev_ptr; 247 atomic_set(&ib_req->ib_bio_cnt, 0); 248 return &ib_req->ib_task; 249 } 250 251 static unsigned long long iblock_emulate_read_cap_with_block_size( 252 struct se_device *dev, 253 struct block_device *bd, 254 struct request_queue *q) 255 { 256 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode), 257 bdev_logical_block_size(bd)) - 1); 258 u32 block_size = bdev_logical_block_size(bd); 259 260 if (block_size == DEV_ATTRIB(dev)->block_size) 261 return blocks_long; 262 263 switch (block_size) { 264 case 4096: 265 switch (DEV_ATTRIB(dev)->block_size) { 266 case 2048: 267 blocks_long <<= 1; 268 break; 269 case 1024: 270 blocks_long <<= 2; 271 break; 272 case 512: 273 blocks_long <<= 3; 274 default: 275 break; 276 } 277 break; 278 case 2048: 279 switch (DEV_ATTRIB(dev)->block_size) { 280 case 4096: 281 blocks_long >>= 1; 282 break; 283 case 1024: 284 blocks_long <<= 1; 285 break; 286 case 512: 287 blocks_long <<= 2; 288 break; 289 default: 290 break; 291 } 292 break; 293 case 1024: 294 switch (DEV_ATTRIB(dev)->block_size) { 295 case 4096: 296 blocks_long >>= 2; 297 break; 298 case 2048: 299 blocks_long >>= 1; 300 break; 301 case 512: 302 blocks_long <<= 1; 303 break; 304 default: 305 break; 306 } 307 break; 308 case 512: 309 switch (DEV_ATTRIB(dev)->block_size) { 310 case 4096: 311 blocks_long >>= 3; 312 break; 313 case 2048: 314 blocks_long >>= 2; 315 break; 316 case 1024: 317 blocks_long >>= 1; 318 break; 319 default: 320 break; 321 } 322 break; 323 default: 324 break; 325 } 326 327 return blocks_long; 328 } 329 330 /* 331 * Emulate SYCHRONIZE_CACHE_* 332 */ 333 static void iblock_emulate_sync_cache(struct se_task *task) 334 { 335 struct se_cmd *cmd = TASK_CMD(task); 336 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr; 337 int immed = (T_TASK(cmd)->t_task_cdb[1] & 0x2); 338 sector_t error_sector; 339 int ret; 340 341 /* 342 * If the Immediate bit is set, queue up the GOOD response 343 * for this SYNCHRONIZE_CACHE op 344 */ 345 if (immed) 346 transport_complete_sync_cache(cmd, 1); 347 348 /* 349 * blkdev_issue_flush() does not support a specifying a range, so 350 * we have to flush the entire cache. 351 */ 352 ret = blkdev_issue_flush(ib_dev->ibd_bd, GFP_KERNEL, &error_sector); 353 if (ret != 0) { 354 printk(KERN_ERR "IBLOCK: block_issue_flush() failed: %d " 355 " error_sector: %llu\n", ret, 356 (unsigned long long)error_sector); 357 } 358 359 if (!immed) 360 transport_complete_sync_cache(cmd, ret == 0); 361 } 362 363 /* 364 * Tell TCM Core that we are capable of WriteCache emulation for 365 * an underlying struct se_device. 366 */ 367 static int iblock_emulated_write_cache(struct se_device *dev) 368 { 369 return 1; 370 } 371 372 static int iblock_emulated_dpo(struct se_device *dev) 373 { 374 return 0; 375 } 376 377 /* 378 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs 379 * for TYPE_DISK. 380 */ 381 static int iblock_emulated_fua_write(struct se_device *dev) 382 { 383 return 1; 384 } 385 386 static int iblock_emulated_fua_read(struct se_device *dev) 387 { 388 return 0; 389 } 390 391 static int iblock_do_task(struct se_task *task) 392 { 393 struct se_device *dev = task->task_se_cmd->se_dev; 394 struct iblock_req *req = IBLOCK_REQ(task); 395 struct iblock_dev *ibd = (struct iblock_dev *)req->ib_dev; 396 struct request_queue *q = bdev_get_queue(ibd->ibd_bd); 397 struct bio *bio = req->ib_bio, *nbio = NULL; 398 int rw; 399 400 if (task->task_data_direction == DMA_TO_DEVICE) { 401 /* 402 * Force data to disk if we pretend to not have a volatile 403 * write cache, or the initiator set the Force Unit Access bit. 404 */ 405 if (DEV_ATTRIB(dev)->emulate_write_cache == 0 || 406 (DEV_ATTRIB(dev)->emulate_fua_write > 0 && 407 T_TASK(task->task_se_cmd)->t_tasks_fua)) 408 rw = WRITE_FUA; 409 else 410 rw = WRITE; 411 } else { 412 rw = READ; 413 } 414 415 while (bio) { 416 nbio = bio->bi_next; 417 bio->bi_next = NULL; 418 DEBUG_IBLOCK("Calling submit_bio() task: %p bio: %p" 419 " bio->bi_sector: %llu\n", task, bio, bio->bi_sector); 420 421 submit_bio(rw, bio); 422 bio = nbio; 423 } 424 425 if (q->unplug_fn) 426 q->unplug_fn(q); 427 return PYX_TRANSPORT_SENT_TO_TRANSPORT; 428 } 429 430 static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range) 431 { 432 struct iblock_dev *ibd = dev->dev_ptr; 433 struct block_device *bd = ibd->ibd_bd; 434 int barrier = 0; 435 436 return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier); 437 } 438 439 static void iblock_free_task(struct se_task *task) 440 { 441 struct iblock_req *req = IBLOCK_REQ(task); 442 struct bio *bio, *hbio = req->ib_bio; 443 /* 444 * We only release the bio(s) here if iblock_bio_done() has not called 445 * bio_put() -> iblock_bio_destructor(). 446 */ 447 while (hbio != NULL) { 448 bio = hbio; 449 hbio = hbio->bi_next; 450 bio->bi_next = NULL; 451 bio_put(bio); 452 } 453 454 kfree(req); 455 } 456 457 enum { 458 Opt_udev_path, Opt_force, Opt_err 459 }; 460 461 static match_table_t tokens = { 462 {Opt_udev_path, "udev_path=%s"}, 463 {Opt_force, "force=%d"}, 464 {Opt_err, NULL} 465 }; 466 467 static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba, 468 struct se_subsystem_dev *se_dev, 469 const char *page, ssize_t count) 470 { 471 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr; 472 char *orig, *ptr, *opts; 473 substring_t args[MAX_OPT_ARGS]; 474 int ret = 0, arg, token; 475 476 opts = kstrdup(page, GFP_KERNEL); 477 if (!opts) 478 return -ENOMEM; 479 480 orig = opts; 481 482 while ((ptr = strsep(&opts, ",")) != NULL) { 483 if (!*ptr) 484 continue; 485 486 token = match_token(ptr, tokens, args); 487 switch (token) { 488 case Opt_udev_path: 489 if (ib_dev->ibd_bd) { 490 printk(KERN_ERR "Unable to set udev_path= while" 491 " ib_dev->ibd_bd exists\n"); 492 ret = -EEXIST; 493 goto out; 494 } 495 496 ret = snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN, 497 "%s", match_strdup(&args[0])); 498 printk(KERN_INFO "IBLOCK: Referencing UDEV path: %s\n", 499 ib_dev->ibd_udev_path); 500 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH; 501 break; 502 case Opt_force: 503 match_int(args, &arg); 504 ib_dev->ibd_force = arg; 505 printk(KERN_INFO "IBLOCK: Set force=%d\n", 506 ib_dev->ibd_force); 507 break; 508 default: 509 break; 510 } 511 } 512 513 out: 514 kfree(orig); 515 return (!ret) ? count : ret; 516 } 517 518 static ssize_t iblock_check_configfs_dev_params( 519 struct se_hba *hba, 520 struct se_subsystem_dev *se_dev) 521 { 522 struct iblock_dev *ibd = se_dev->se_dev_su_ptr; 523 524 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) { 525 printk(KERN_ERR "Missing udev_path= parameters for IBLOCK\n"); 526 return -1; 527 } 528 529 return 0; 530 } 531 532 static ssize_t iblock_show_configfs_dev_params( 533 struct se_hba *hba, 534 struct se_subsystem_dev *se_dev, 535 char *b) 536 { 537 struct iblock_dev *ibd = se_dev->se_dev_su_ptr; 538 struct block_device *bd = ibd->ibd_bd; 539 char buf[BDEVNAME_SIZE]; 540 ssize_t bl = 0; 541 542 if (bd) 543 bl += sprintf(b + bl, "iBlock device: %s", 544 bdevname(bd, buf)); 545 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) { 546 bl += sprintf(b + bl, " UDEV PATH: %s\n", 547 ibd->ibd_udev_path); 548 } else 549 bl += sprintf(b + bl, "\n"); 550 551 bl += sprintf(b + bl, " "); 552 if (bd) { 553 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n", 554 ibd->ibd_major, ibd->ibd_minor, (!bd->bd_contains) ? 555 "" : (bd->bd_holder == (struct iblock_dev *)ibd) ? 556 "CLAIMED: IBLOCK" : "CLAIMED: OS"); 557 } else { 558 bl += sprintf(b + bl, "Major: %d Minor: %d\n", 559 ibd->ibd_major, ibd->ibd_minor); 560 } 561 562 return bl; 563 } 564 565 static void iblock_bio_destructor(struct bio *bio) 566 { 567 struct se_task *task = bio->bi_private; 568 struct iblock_dev *ib_dev = task->se_dev->dev_ptr; 569 570 bio_free(bio, ib_dev->ibd_bio_set); 571 } 572 573 static struct bio *iblock_get_bio( 574 struct se_task *task, 575 struct iblock_req *ib_req, 576 struct iblock_dev *ib_dev, 577 int *ret, 578 sector_t lba, 579 u32 sg_num) 580 { 581 struct bio *bio; 582 583 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set); 584 if (!(bio)) { 585 printk(KERN_ERR "Unable to allocate memory for bio\n"); 586 *ret = PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES; 587 return NULL; 588 } 589 590 DEBUG_IBLOCK("Allocated bio: %p task_sg_num: %u using ibd_bio_set:" 591 " %p\n", bio, task->task_sg_num, ib_dev->ibd_bio_set); 592 DEBUG_IBLOCK("Allocated bio: %p task_size: %u\n", bio, task->task_size); 593 594 bio->bi_bdev = ib_dev->ibd_bd; 595 bio->bi_private = (void *) task; 596 bio->bi_destructor = iblock_bio_destructor; 597 bio->bi_end_io = &iblock_bio_done; 598 bio->bi_sector = lba; 599 atomic_inc(&ib_req->ib_bio_cnt); 600 601 DEBUG_IBLOCK("Set bio->bi_sector: %llu\n", bio->bi_sector); 602 DEBUG_IBLOCK("Set ib_req->ib_bio_cnt: %d\n", 603 atomic_read(&ib_req->ib_bio_cnt)); 604 return bio; 605 } 606 607 static int iblock_map_task_SG(struct se_task *task) 608 { 609 struct se_cmd *cmd = task->task_se_cmd; 610 struct se_device *dev = SE_DEV(cmd); 611 struct iblock_dev *ib_dev = task->se_dev->dev_ptr; 612 struct iblock_req *ib_req = IBLOCK_REQ(task); 613 struct bio *bio = NULL, *hbio = NULL, *tbio = NULL; 614 struct scatterlist *sg; 615 int ret = 0; 616 u32 i, sg_num = task->task_sg_num; 617 sector_t block_lba; 618 /* 619 * Do starting conversion up from non 512-byte blocksize with 620 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO. 621 */ 622 if (DEV_ATTRIB(dev)->block_size == 4096) 623 block_lba = (task->task_lba << 3); 624 else if (DEV_ATTRIB(dev)->block_size == 2048) 625 block_lba = (task->task_lba << 2); 626 else if (DEV_ATTRIB(dev)->block_size == 1024) 627 block_lba = (task->task_lba << 1); 628 else if (DEV_ATTRIB(dev)->block_size == 512) 629 block_lba = task->task_lba; 630 else { 631 printk(KERN_ERR "Unsupported SCSI -> BLOCK LBA conversion:" 632 " %u\n", DEV_ATTRIB(dev)->block_size); 633 return PYX_TRANSPORT_LU_COMM_FAILURE; 634 } 635 636 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, block_lba, sg_num); 637 if (!(bio)) 638 return ret; 639 640 ib_req->ib_bio = bio; 641 hbio = tbio = bio; 642 /* 643 * Use fs/bio.c:bio_add_pages() to setup the bio_vec maplist 644 * from TCM struct se_mem -> task->task_sg -> struct scatterlist memory. 645 */ 646 for_each_sg(task->task_sg, sg, task->task_sg_num, i) { 647 DEBUG_IBLOCK("task: %p bio: %p Calling bio_add_page(): page:" 648 " %p len: %u offset: %u\n", task, bio, sg_page(sg), 649 sg->length, sg->offset); 650 again: 651 ret = bio_add_page(bio, sg_page(sg), sg->length, sg->offset); 652 if (ret != sg->length) { 653 654 DEBUG_IBLOCK("*** Set bio->bi_sector: %llu\n", 655 bio->bi_sector); 656 DEBUG_IBLOCK("** task->task_size: %u\n", 657 task->task_size); 658 DEBUG_IBLOCK("*** bio->bi_max_vecs: %u\n", 659 bio->bi_max_vecs); 660 DEBUG_IBLOCK("*** bio->bi_vcnt: %u\n", 661 bio->bi_vcnt); 662 663 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, 664 block_lba, sg_num); 665 if (!(bio)) 666 goto fail; 667 668 tbio = tbio->bi_next = bio; 669 DEBUG_IBLOCK("-----------------> Added +1 bio: %p to" 670 " list, Going to again\n", bio); 671 goto again; 672 } 673 /* Always in 512 byte units for Linux/Block */ 674 block_lba += sg->length >> IBLOCK_LBA_SHIFT; 675 sg_num--; 676 DEBUG_IBLOCK("task: %p bio-add_page() passed!, decremented" 677 " sg_num to %u\n", task, sg_num); 678 DEBUG_IBLOCK("task: %p bio_add_page() passed!, increased lba" 679 " to %llu\n", task, block_lba); 680 DEBUG_IBLOCK("task: %p bio_add_page() passed!, bio->bi_vcnt:" 681 " %u\n", task, bio->bi_vcnt); 682 } 683 684 return 0; 685 fail: 686 while (hbio) { 687 bio = hbio; 688 hbio = hbio->bi_next; 689 bio->bi_next = NULL; 690 bio_put(bio); 691 } 692 return ret; 693 } 694 695 static unsigned char *iblock_get_cdb(struct se_task *task) 696 { 697 return IBLOCK_REQ(task)->ib_scsi_cdb; 698 } 699 700 static u32 iblock_get_device_rev(struct se_device *dev) 701 { 702 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */ 703 } 704 705 static u32 iblock_get_device_type(struct se_device *dev) 706 { 707 return TYPE_DISK; 708 } 709 710 static sector_t iblock_get_blocks(struct se_device *dev) 711 { 712 struct iblock_dev *ibd = dev->dev_ptr; 713 struct block_device *bd = ibd->ibd_bd; 714 struct request_queue *q = bdev_get_queue(bd); 715 716 return iblock_emulate_read_cap_with_block_size(dev, bd, q); 717 } 718 719 static void iblock_bio_done(struct bio *bio, int err) 720 { 721 struct se_task *task = bio->bi_private; 722 struct iblock_req *ibr = IBLOCK_REQ(task); 723 /* 724 * Set -EIO if !BIO_UPTODATE and the passed is still err=0 725 */ 726 if (!(test_bit(BIO_UPTODATE, &bio->bi_flags)) && !(err)) 727 err = -EIO; 728 729 if (err != 0) { 730 printk(KERN_ERR "test_bit(BIO_UPTODATE) failed for bio: %p," 731 " err: %d\n", bio, err); 732 /* 733 * Bump the ib_bio_err_cnt and release bio. 734 */ 735 atomic_inc(&ibr->ib_bio_err_cnt); 736 smp_mb__after_atomic_inc(); 737 bio_put(bio); 738 /* 739 * Wait to complete the task until the last bio as completed. 740 */ 741 if (!(atomic_dec_and_test(&ibr->ib_bio_cnt))) 742 return; 743 744 ibr->ib_bio = NULL; 745 transport_complete_task(task, 0); 746 return; 747 } 748 DEBUG_IBLOCK("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n", 749 task, bio, task->task_lba, bio->bi_sector, err); 750 /* 751 * bio_put() will call iblock_bio_destructor() to release the bio back 752 * to ibr->ib_bio_set. 753 */ 754 bio_put(bio); 755 /* 756 * Wait to complete the task until the last bio as completed. 757 */ 758 if (!(atomic_dec_and_test(&ibr->ib_bio_cnt))) 759 return; 760 /* 761 * Return GOOD status for task if zero ib_bio_err_cnt exists. 762 */ 763 ibr->ib_bio = NULL; 764 transport_complete_task(task, (!atomic_read(&ibr->ib_bio_err_cnt))); 765 } 766 767 static struct se_subsystem_api iblock_template = { 768 .name = "iblock", 769 .owner = THIS_MODULE, 770 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, 771 .map_task_SG = iblock_map_task_SG, 772 .attach_hba = iblock_attach_hba, 773 .detach_hba = iblock_detach_hba, 774 .allocate_virtdevice = iblock_allocate_virtdevice, 775 .create_virtdevice = iblock_create_virtdevice, 776 .free_device = iblock_free_device, 777 .dpo_emulated = iblock_emulated_dpo, 778 .fua_write_emulated = iblock_emulated_fua_write, 779 .fua_read_emulated = iblock_emulated_fua_read, 780 .write_cache_emulated = iblock_emulated_write_cache, 781 .alloc_task = iblock_alloc_task, 782 .do_task = iblock_do_task, 783 .do_discard = iblock_do_discard, 784 .do_sync_cache = iblock_emulate_sync_cache, 785 .free_task = iblock_free_task, 786 .check_configfs_dev_params = iblock_check_configfs_dev_params, 787 .set_configfs_dev_params = iblock_set_configfs_dev_params, 788 .show_configfs_dev_params = iblock_show_configfs_dev_params, 789 .get_cdb = iblock_get_cdb, 790 .get_device_rev = iblock_get_device_rev, 791 .get_device_type = iblock_get_device_type, 792 .get_blocks = iblock_get_blocks, 793 }; 794 795 static int __init iblock_module_init(void) 796 { 797 return transport_subsystem_register(&iblock_template); 798 } 799 800 static void iblock_module_exit(void) 801 { 802 transport_subsystem_release(&iblock_template); 803 } 804 805 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin"); 806 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 807 MODULE_LICENSE("GPL"); 808 809 module_init(iblock_module_init); 810 module_exit(iblock_module_exit); 811