?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
spi-topcliff-pch: add recovery processing in case wait-event timeout
[zen-stable.git] / drivers / target / target_core_iblock.c
blob8572eae62da7a20399216db03ea04fe9fa1dde3e
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/string.h>
31 #include <linux/parser.h>
32 #include <linux/timer.h>
33 #include <linux/fs.h>
34 #include <linux/blkdev.h>
35 #include <linux/slab.h>
36 #include <linux/spinlock.h>
37 #include <linux/bio.h>
38 #include <linux/genhd.h>
39 #include <linux/file.h>
40 #include <linux/module.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_backend.h>
46
47 #include "target_core_iblock.h"
48
49 static struct se_subsystem_api iblock_template;
50
51 static void iblock_bio_done(struct bio *, int);
52
53 /* iblock_attach_hba(): (Part of se_subsystem_api_t template)
54 *
55 *
56 */
57 static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
58 {
59 struct iblock_hba *ib_host;
60
61 ib_host = kzalloc(sizeof(struct iblock_hba), GFP_KERNEL);
62 if (!ib_host) {
63 pr_err("Unable to allocate memory for"
64 " struct iblock_hba\n");
65 return -ENOMEM;
66 }
67
68 ib_host->iblock_host_id = host_id;
69
70 hba->hba_ptr = ib_host;
71
72 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
73 " Generic Target Core Stack %s\n", hba->hba_id,
74 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
75
76 pr_debug("CORE_HBA[%d] - Attached iBlock HBA: %u to Generic\n",
77 hba->hba_id, ib_host->iblock_host_id);
78
79 return 0;
80 }
81
82 static void iblock_detach_hba(struct se_hba *hba)
83 {
84 struct iblock_hba *ib_host = hba->hba_ptr;
85
86 pr_debug("CORE_HBA[%d] - Detached iBlock HBA: %u from Generic"
87 " Target Core\n", hba->hba_id, ib_host->iblock_host_id);
88
89 kfree(ib_host);
90 hba->hba_ptr = NULL;
91 }
92
93 static void *iblock_allocate_virtdevice(struct se_hba *hba, const char *name)
94 {
95 struct iblock_dev *ib_dev = NULL;
96 struct iblock_hba *ib_host = hba->hba_ptr;
97
98 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
99 if (!ib_dev) {
100 pr_err("Unable to allocate struct iblock_dev\n");
101 return NULL;
102 }
103 ib_dev->ibd_host = ib_host;
104
105 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
106
107 return ib_dev;
108 }
109
110 static struct se_device *iblock_create_virtdevice(
111 struct se_hba *hba,
112 struct se_subsystem_dev *se_dev,
113 void *p)
114 {
115 struct iblock_dev *ib_dev = p;
116 struct se_device *dev;
117 struct se_dev_limits dev_limits;
118 struct block_device *bd = NULL;
119 struct request_queue *q;
120 struct queue_limits *limits;
121 u32 dev_flags = 0;
122 int ret = -EINVAL;
123
124 if (!ib_dev) {
125 pr_err("Unable to locate struct iblock_dev parameter\n");
126 return ERR_PTR(ret);
127 }
128 memset(&dev_limits, 0, sizeof(struct se_dev_limits));
129 /*
130 * These settings need to be made tunable..
131 */
132 ib_dev->ibd_bio_set = bioset_create(32, 0);
133 if (!ib_dev->ibd_bio_set) {
134 pr_err("IBLOCK: Unable to create bioset()\n");
135 return ERR_PTR(-ENOMEM);
136 }
137 pr_debug("IBLOCK: Created bio_set()\n");
138 /*
139 * iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path
140 * must already have been set in order for echo 1 > $HBA/$DEV/enable to run.
141 */
142 pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
143 ib_dev->ibd_udev_path);
144
145 bd = blkdev_get_by_path(ib_dev->ibd_udev_path,
146 FMODE_WRITE|FMODE_READ|FMODE_EXCL, ib_dev);
147 if (IS_ERR(bd)) {
148 ret = PTR_ERR(bd);
149 goto failed;
150 }
151 /*
152 * Setup the local scope queue_limits from struct request_queue->limits
153 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
154 */
155 q = bdev_get_queue(bd);
156 limits = &dev_limits.limits;
157 limits->logical_block_size = bdev_logical_block_size(bd);
158 limits->max_hw_sectors = queue_max_hw_sectors(q);
159 limits->max_sectors = queue_max_sectors(q);
160 dev_limits.hw_queue_depth = q->nr_requests;
161 dev_limits.queue_depth = q->nr_requests;
162
163 ib_dev->ibd_bd = bd;
164
165 dev = transport_add_device_to_core_hba(hba,
166 &iblock_template, se_dev, dev_flags, ib_dev,
167 &dev_limits, "IBLOCK", IBLOCK_VERSION);
168 if (!dev)
169 goto failed;
170
171 /*
172 * Check if the underlying struct block_device request_queue supports
173 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
174 * in ATA and we need to set TPE=1
175 */
176 if (blk_queue_discard(q)) {
177 dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count =
178 q->limits.max_discard_sectors;
179 /*
180 * Currently hardcoded to 1 in Linux/SCSI code..
181 */
182 dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count = 1;
183 dev->se_sub_dev->se_dev_attrib.unmap_granularity =
184 q->limits.discard_granularity >> 9;
185 dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment =
186 q->limits.discard_alignment;
187
188 pr_debug("IBLOCK: BLOCK Discard support available,"
189 " disabled by default\n");
190 }
191
192 if (blk_queue_nonrot(q))
193 dev->se_sub_dev->se_dev_attrib.is_nonrot = 1;
194
195 return dev;
196
197 failed:
198 if (ib_dev->ibd_bio_set) {
199 bioset_free(ib_dev->ibd_bio_set);
200 ib_dev->ibd_bio_set = NULL;
201 }
202 ib_dev->ibd_bd = NULL;
203 return ERR_PTR(ret);
204 }
205
206 static void iblock_free_device(void *p)
207 {
208 struct iblock_dev *ib_dev = p;
209
210 if (ib_dev->ibd_bd != NULL)
211 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
212 if (ib_dev->ibd_bio_set != NULL)
213 bioset_free(ib_dev->ibd_bio_set);
214 kfree(ib_dev);
215 }
216
217 static inline struct iblock_req *IBLOCK_REQ(struct se_task *task)
218 {
219 return container_of(task, struct iblock_req, ib_task);
220 }
221
222 static struct se_task *
223 iblock_alloc_task(unsigned char *cdb)
224 {
225 struct iblock_req *ib_req;
226
227 ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
228 if (!ib_req) {
229 pr_err("Unable to allocate memory for struct iblock_req\n");
230 return NULL;
231 }
232
233 atomic_set(&ib_req->ib_bio_cnt, 0);
234 return &ib_req->ib_task;
235 }
236
237 static unsigned long long iblock_emulate_read_cap_with_block_size(
238 struct se_device *dev,
239 struct block_device *bd,
240 struct request_queue *q)
241 {
242 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
243 bdev_logical_block_size(bd)) - 1);
244 u32 block_size = bdev_logical_block_size(bd);
245
246 if (block_size == dev->se_sub_dev->se_dev_attrib.block_size)
247 return blocks_long;
248
249 switch (block_size) {
250 case 4096:
251 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
252 case 2048:
253 blocks_long <<= 1;
254 break;
255 case 1024:
256 blocks_long <<= 2;
257 break;
258 case 512:
259 blocks_long <<= 3;
260 default:
261 break;
262 }
263 break;
264 case 2048:
265 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
266 case 4096:
267 blocks_long >>= 1;
268 break;
269 case 1024:
270 blocks_long <<= 1;
271 break;
272 case 512:
273 blocks_long <<= 2;
274 break;
275 default:
276 break;
277 }
278 break;
279 case 1024:
280 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
281 case 4096:
282 blocks_long >>= 2;
283 break;
284 case 2048:
285 blocks_long >>= 1;
286 break;
287 case 512:
288 blocks_long <<= 1;
289 break;
290 default:
291 break;
292 }
293 break;
294 case 512:
295 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
296 case 4096:
297 blocks_long >>= 3;
298 break;
299 case 2048:
300 blocks_long >>= 2;
301 break;
302 case 1024:
303 blocks_long >>= 1;
304 break;
305 default:
306 break;
307 }
308 break;
309 default:
310 break;
311 }
312
313 return blocks_long;
314 }
315
316 static void iblock_end_io_flush(struct bio *bio, int err)
317 {
318 struct se_cmd *cmd = bio->bi_private;
319
320 if (err)
321 pr_err("IBLOCK: cache flush failed: %d\n", err);
322
323 if (cmd)
324 transport_complete_sync_cache(cmd, err == 0);
325 bio_put(bio);
326 }
327
328 /*
329 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
330 * always flush the whole cache.
331 */
332 static void iblock_emulate_sync_cache(struct se_task *task)
333 {
334 struct se_cmd *cmd = task->task_se_cmd;
335 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
336 int immed = (cmd->t_task_cdb[1] & 0x2);
337 struct bio *bio;
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 bio = bio_alloc(GFP_KERNEL, 0);
347 bio->bi_end_io = iblock_end_io_flush;
348 bio->bi_bdev = ib_dev->ibd_bd;
349 if (!immed)
350 bio->bi_private = cmd;
351 submit_bio(WRITE_FLUSH, bio);
352 }
353
354 static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range)
355 {
356 struct iblock_dev *ibd = dev->dev_ptr;
357 struct block_device *bd = ibd->ibd_bd;
358 int barrier = 0;
359
360 return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier);
361 }
362
363 static void iblock_free_task(struct se_task *task)
364 {
365 kfree(IBLOCK_REQ(task));
366 }
367
368 enum {
369 Opt_udev_path, Opt_force, Opt_err
370 };
371
372 static match_table_t tokens = {
373 {Opt_udev_path, "udev_path=%s"},
374 {Opt_force, "force=%d"},
375 {Opt_err, NULL}
376 };
377
378 static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
379 struct se_subsystem_dev *se_dev,
380 const char *page, ssize_t count)
381 {
382 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr;
383 char *orig, *ptr, *arg_p, *opts;
384 substring_t args[MAX_OPT_ARGS];
385 int ret = 0, token;
386
387 opts = kstrdup(page, GFP_KERNEL);
388 if (!opts)
389 return -ENOMEM;
390
391 orig = opts;
392
393 while ((ptr = strsep(&opts, ",\n")) != NULL) {
394 if (!*ptr)
395 continue;
396
397 token = match_token(ptr, tokens, args);
398 switch (token) {
399 case Opt_udev_path:
400 if (ib_dev->ibd_bd) {
401 pr_err("Unable to set udev_path= while"
402 " ib_dev->ibd_bd exists\n");
403 ret = -EEXIST;
404 goto out;
405 }
406 arg_p = match_strdup(&args[0]);
407 if (!arg_p) {
408 ret = -ENOMEM;
409 break;
410 }
411 snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
412 "%s", arg_p);
413 kfree(arg_p);
414 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
415 ib_dev->ibd_udev_path);
416 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
417 break;
418 case Opt_force:
419 break;
420 default:
421 break;
422 }
423 }
424
425 out:
426 kfree(orig);
427 return (!ret) ? count : ret;
428 }
429
430 static ssize_t iblock_check_configfs_dev_params(
431 struct se_hba *hba,
432 struct se_subsystem_dev *se_dev)
433 {
434 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
435
436 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) {
437 pr_err("Missing udev_path= parameters for IBLOCK\n");
438 return -EINVAL;
439 }
440
441 return 0;
442 }
443
444 static ssize_t iblock_show_configfs_dev_params(
445 struct se_hba *hba,
446 struct se_subsystem_dev *se_dev,
447 char *b)
448 {
449 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
450 struct block_device *bd = ibd->ibd_bd;
451 char buf[BDEVNAME_SIZE];
452 ssize_t bl = 0;
453
454 if (bd)
455 bl += sprintf(b + bl, "iBlock device: %s",
456 bdevname(bd, buf));
457 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) {
458 bl += sprintf(b + bl, " UDEV PATH: %s\n",
459 ibd->ibd_udev_path);
460 } else
461 bl += sprintf(b + bl, "\n");
462
463 bl += sprintf(b + bl, " ");
464 if (bd) {
465 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
466 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
467 "" : (bd->bd_holder == ibd) ?
468 "CLAIMED: IBLOCK" : "CLAIMED: OS");
469 } else {
470 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
471 }
472
473 return bl;
474 }
475
476 static void iblock_bio_destructor(struct bio *bio)
477 {
478 struct se_task *task = bio->bi_private;
479 struct iblock_dev *ib_dev = task->task_se_cmd->se_dev->dev_ptr;
480
481 bio_free(bio, ib_dev->ibd_bio_set);
482 }
483
484 static struct bio *
485 iblock_get_bio(struct se_task *task, sector_t lba, u32 sg_num)
486 {
487 struct iblock_dev *ib_dev = task->task_se_cmd->se_dev->dev_ptr;
488 struct iblock_req *ib_req = IBLOCK_REQ(task);
489 struct bio *bio;
490
491 /*
492 * Only allocate as many vector entries as the bio code allows us to,
493 * we'll loop later on until we have handled the whole request.
494 */
495 if (sg_num > BIO_MAX_PAGES)
496 sg_num = BIO_MAX_PAGES;
497
498 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
499 if (!bio) {
500 pr_err("Unable to allocate memory for bio\n");
501 return NULL;
502 }
503
504 pr_debug("Allocated bio: %p task_sg_nents: %u using ibd_bio_set:"
505 " %p\n", bio, task->task_sg_nents, ib_dev->ibd_bio_set);
506 pr_debug("Allocated bio: %p task_size: %u\n", bio, task->task_size);
507
508 bio->bi_bdev = ib_dev->ibd_bd;
509 bio->bi_private = task;
510 bio->bi_destructor = iblock_bio_destructor;
511 bio->bi_end_io = &iblock_bio_done;
512 bio->bi_sector = lba;
513 atomic_inc(&ib_req->ib_bio_cnt);
514
515 pr_debug("Set bio->bi_sector: %llu\n", (unsigned long long)bio->bi_sector);
516 pr_debug("Set ib_req->ib_bio_cnt: %d\n",
517 atomic_read(&ib_req->ib_bio_cnt));
518 return bio;
519 }
520
521 static int iblock_do_task(struct se_task *task)
522 {
523 struct se_cmd *cmd = task->task_se_cmd;
524 struct se_device *dev = cmd->se_dev;
525 struct bio *bio;
526 struct bio_list list;
527 struct scatterlist *sg;
528 u32 i, sg_num = task->task_sg_nents;
529 sector_t block_lba;
530 struct blk_plug plug;
531 int rw;
532
533 if (task->task_data_direction == DMA_TO_DEVICE) {
534 /*
535 * Force data to disk if we pretend to not have a volatile
536 * write cache, or the initiator set the Force Unit Access bit.
537 */
538 if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache == 0 ||
539 (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
540 (cmd->se_cmd_flags & SCF_FUA)))
541 rw = WRITE_FUA;
542 else
543 rw = WRITE;
544 } else {
545 rw = READ;
546 }
547
548 /*
549 * Do starting conversion up from non 512-byte blocksize with
550 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO.
551 */
552 if (dev->se_sub_dev->se_dev_attrib.block_size == 4096)
553 block_lba = (task->task_lba << 3);
554 else if (dev->se_sub_dev->se_dev_attrib.block_size == 2048)
555 block_lba = (task->task_lba << 2);
556 else if (dev->se_sub_dev->se_dev_attrib.block_size == 1024)
557 block_lba = (task->task_lba << 1);
558 else if (dev->se_sub_dev->se_dev_attrib.block_size == 512)
559 block_lba = task->task_lba;
560 else {
561 pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
562 " %u\n", dev->se_sub_dev->se_dev_attrib.block_size);
563 cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
564 return -ENOSYS;
565 }
566
567 bio = iblock_get_bio(task, block_lba, sg_num);
568 if (!bio) {
569 cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
570 return -ENOMEM;
571 }
572
573 bio_list_init(&list);
574 bio_list_add(&list, bio);
575
576 for_each_sg(task->task_sg, sg, task->task_sg_nents, i) {
577 /*
578 * XXX: if the length the device accepts is shorter than the
579 * length of the S/G list entry this will cause and
580 * endless loop. Better hope no driver uses huge pages.
581 */
582 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
583 != sg->length) {
584 bio = iblock_get_bio(task, block_lba, sg_num);
585 if (!bio)
586 goto fail;
587 bio_list_add(&list, bio);
588 }
589
590 /* Always in 512 byte units for Linux/Block */
591 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
592 sg_num--;
593 }
594
595 blk_start_plug(&plug);
596 while ((bio = bio_list_pop(&list)))
597 submit_bio(rw, bio);
598 blk_finish_plug(&plug);
599
600 return 0;
601
602 fail:
603 while ((bio = bio_list_pop(&list)))
604 bio_put(bio);
605 cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
606 return -ENOMEM;
607 }
608
609 static u32 iblock_get_device_rev(struct se_device *dev)
610 {
611 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
612 }
613
614 static u32 iblock_get_device_type(struct se_device *dev)
615 {
616 return TYPE_DISK;
617 }
618
619 static sector_t iblock_get_blocks(struct se_device *dev)
620 {
621 struct iblock_dev *ibd = dev->dev_ptr;
622 struct block_device *bd = ibd->ibd_bd;
623 struct request_queue *q = bdev_get_queue(bd);
624
625 return iblock_emulate_read_cap_with_block_size(dev, bd, q);
626 }
627
628 static void iblock_bio_done(struct bio *bio, int err)
629 {
630 struct se_task *task = bio->bi_private;
631 struct iblock_req *ibr = IBLOCK_REQ(task);
632
633 /*
634 * Set -EIO if !BIO_UPTODATE and the passed is still err=0
635 */
636 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
637 err = -EIO;
638
639 if (err != 0) {
640 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
641 " err: %d\n", bio, err);
642 /*
643 * Bump the ib_bio_err_cnt and release bio.
644 */
645 atomic_inc(&ibr->ib_bio_err_cnt);
646 smp_mb__after_atomic_inc();
647 }
648
649 bio_put(bio);
650
651 if (!atomic_dec_and_test(&ibr->ib_bio_cnt))
652 return;
653
654 pr_debug("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n",
655 task, bio, task->task_lba,
656 (unsigned long long)bio->bi_sector, err);
657
658 transport_complete_task(task, !atomic_read(&ibr->ib_bio_err_cnt));
659 }
660
661 static struct se_subsystem_api iblock_template = {
662 .name = "iblock",
663 .owner = THIS_MODULE,
664 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
665 .write_cache_emulated = 1,
666 .fua_write_emulated = 1,
667 .attach_hba = iblock_attach_hba,
668 .detach_hba = iblock_detach_hba,
669 .allocate_virtdevice = iblock_allocate_virtdevice,
670 .create_virtdevice = iblock_create_virtdevice,
671 .free_device = iblock_free_device,
672 .alloc_task = iblock_alloc_task,
673 .do_task = iblock_do_task,
674 .do_discard = iblock_do_discard,
675 .do_sync_cache = iblock_emulate_sync_cache,
676 .free_task = iblock_free_task,
677 .check_configfs_dev_params = iblock_check_configfs_dev_params,
678 .set_configfs_dev_params = iblock_set_configfs_dev_params,
679 .show_configfs_dev_params = iblock_show_configfs_dev_params,
680 .get_device_rev = iblock_get_device_rev,
681 .get_device_type = iblock_get_device_type,
682 .get_blocks = iblock_get_blocks,
683 };
684
685 static int __init iblock_module_init(void)
686 {
687 return transport_subsystem_register(&iblock_template);
688 }
689
690 static void iblock_module_exit(void)
691 {
692 transport_subsystem_release(&iblock_template);
693 }
694
695 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
696 MODULE_AUTHOR("nab@Linux-iSCSI.org");
697 MODULE_LICENSE("GPL");
698
699 module_init(iblock_module_init);
700 module_exit(iblock_module_exit);