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Merge 3.2-rc3 into usb-linus
[zen-stable.git] / drivers / target / target_core_iblock.c
blob7698efe29262bfd8a7cb521016da0aff1ff0517d
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_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 static void iblock_end_io_flush(struct bio *bio, int err)
318 {
319 struct se_cmd *cmd = bio->bi_private;
320
321 if (err)
322 pr_err("IBLOCK: cache flush failed: %d\n", err);
323
324 if (cmd)
325 transport_complete_sync_cache(cmd, err == 0);
326 bio_put(bio);
327 }
328
329 /*
330 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
331 * always flush the whole cache.
332 */
333 static void iblock_emulate_sync_cache(struct se_task *task)
334 {
335 struct se_cmd *cmd = task->task_se_cmd;
336 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
337 int immed = (cmd->t_task_cdb[1] & 0x2);
338 struct bio *bio;
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 bio = bio_alloc(GFP_KERNEL, 0);
348 bio->bi_end_io = iblock_end_io_flush;
349 bio->bi_bdev = ib_dev->ibd_bd;
350 if (!immed)
351 bio->bi_private = cmd;
352 submit_bio(WRITE_FLUSH, bio);
353 }
354
355 static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range)
356 {
357 struct iblock_dev *ibd = dev->dev_ptr;
358 struct block_device *bd = ibd->ibd_bd;
359 int barrier = 0;
360
361 return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier);
362 }
363
364 static void iblock_free_task(struct se_task *task)
365 {
366 kfree(IBLOCK_REQ(task));
367 }
368
369 enum {
370 Opt_udev_path, Opt_force, Opt_err
371 };
372
373 static match_table_t tokens = {
374 {Opt_udev_path, "udev_path=%s"},
375 {Opt_force, "force=%d"},
376 {Opt_err, NULL}
377 };
378
379 static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
380 struct se_subsystem_dev *se_dev,
381 const char *page, ssize_t count)
382 {
383 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr;
384 char *orig, *ptr, *arg_p, *opts;
385 substring_t args[MAX_OPT_ARGS];
386 int ret = 0, token;
387
388 opts = kstrdup(page, GFP_KERNEL);
389 if (!opts)
390 return -ENOMEM;
391
392 orig = opts;
393
394 while ((ptr = strsep(&opts, ",")) != NULL) {
395 if (!*ptr)
396 continue;
397
398 token = match_token(ptr, tokens, args);
399 switch (token) {
400 case Opt_udev_path:
401 if (ib_dev->ibd_bd) {
402 pr_err("Unable to set udev_path= while"
403 " ib_dev->ibd_bd exists\n");
404 ret = -EEXIST;
405 goto out;
406 }
407 arg_p = match_strdup(&args[0]);
408 if (!arg_p) {
409 ret = -ENOMEM;
410 break;
411 }
412 snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
413 "%s", arg_p);
414 kfree(arg_p);
415 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
416 ib_dev->ibd_udev_path);
417 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
418 break;
419 case Opt_force:
420 break;
421 default:
422 break;
423 }
424 }
425
426 out:
427 kfree(orig);
428 return (!ret) ? count : ret;
429 }
430
431 static ssize_t iblock_check_configfs_dev_params(
432 struct se_hba *hba,
433 struct se_subsystem_dev *se_dev)
434 {
435 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
436
437 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) {
438 pr_err("Missing udev_path= parameters for IBLOCK\n");
439 return -EINVAL;
440 }
441
442 return 0;
443 }
444
445 static ssize_t iblock_show_configfs_dev_params(
446 struct se_hba *hba,
447 struct se_subsystem_dev *se_dev,
448 char *b)
449 {
450 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
451 struct block_device *bd = ibd->ibd_bd;
452 char buf[BDEVNAME_SIZE];
453 ssize_t bl = 0;
454
455 if (bd)
456 bl += sprintf(b + bl, "iBlock device: %s",
457 bdevname(bd, buf));
458 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) {
459 bl += sprintf(b + bl, " UDEV PATH: %s\n",
460 ibd->ibd_udev_path);
461 } else
462 bl += sprintf(b + bl, "\n");
463
464 bl += sprintf(b + bl, " ");
465 if (bd) {
466 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
467 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
468 "" : (bd->bd_holder == (struct iblock_dev *)ibd) ?
469 "CLAIMED: IBLOCK" : "CLAIMED: OS");
470 } else {
471 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
472 }
473
474 return bl;
475 }
476
477 static void iblock_bio_destructor(struct bio *bio)
478 {
479 struct se_task *task = bio->bi_private;
480 struct iblock_dev *ib_dev = task->task_se_cmd->se_dev->dev_ptr;
481
482 bio_free(bio, ib_dev->ibd_bio_set);
483 }
484
485 static struct bio *
486 iblock_get_bio(struct se_task *task, sector_t lba, u32 sg_num)
487 {
488 struct iblock_dev *ib_dev = task->task_se_cmd->se_dev->dev_ptr;
489 struct iblock_req *ib_req = IBLOCK_REQ(task);
490 struct bio *bio;
491
492 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
493 if (!bio) {
494 pr_err("Unable to allocate memory for bio\n");
495 return NULL;
496 }
497
498 pr_debug("Allocated bio: %p task_sg_nents: %u using ibd_bio_set:"
499 " %p\n", bio, task->task_sg_nents, ib_dev->ibd_bio_set);
500 pr_debug("Allocated bio: %p task_size: %u\n", bio, task->task_size);
501
502 bio->bi_bdev = ib_dev->ibd_bd;
503 bio->bi_private = task;
504 bio->bi_destructor = iblock_bio_destructor;
505 bio->bi_end_io = &iblock_bio_done;
506 bio->bi_sector = lba;
507 atomic_inc(&ib_req->ib_bio_cnt);
508
509 pr_debug("Set bio->bi_sector: %llu\n", (unsigned long long)bio->bi_sector);
510 pr_debug("Set ib_req->ib_bio_cnt: %d\n",
511 atomic_read(&ib_req->ib_bio_cnt));
512 return bio;
513 }
514
515 static int iblock_do_task(struct se_task *task)
516 {
517 struct se_cmd *cmd = task->task_se_cmd;
518 struct se_device *dev = cmd->se_dev;
519 struct bio *bio;
520 struct bio_list list;
521 struct scatterlist *sg;
522 u32 i, sg_num = task->task_sg_nents;
523 sector_t block_lba;
524 struct blk_plug plug;
525 int rw;
526
527 if (task->task_data_direction == DMA_TO_DEVICE) {
528 /*
529 * Force data to disk if we pretend to not have a volatile
530 * write cache, or the initiator set the Force Unit Access bit.
531 */
532 if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache == 0 ||
533 (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
534 task->task_se_cmd->t_tasks_fua))
535 rw = WRITE_FUA;
536 else
537 rw = WRITE;
538 } else {
539 rw = READ;
540 }
541
542 /*
543 * Do starting conversion up from non 512-byte blocksize with
544 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO.
545 */
546 if (dev->se_sub_dev->se_dev_attrib.block_size == 4096)
547 block_lba = (task->task_lba << 3);
548 else if (dev->se_sub_dev->se_dev_attrib.block_size == 2048)
549 block_lba = (task->task_lba << 2);
550 else if (dev->se_sub_dev->se_dev_attrib.block_size == 1024)
551 block_lba = (task->task_lba << 1);
552 else if (dev->se_sub_dev->se_dev_attrib.block_size == 512)
553 block_lba = task->task_lba;
554 else {
555 pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
556 " %u\n", dev->se_sub_dev->se_dev_attrib.block_size);
557 return PYX_TRANSPORT_LU_COMM_FAILURE;
558 }
559
560 bio = iblock_get_bio(task, block_lba, sg_num);
561 if (!bio)
562 return PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
563
564 bio_list_init(&list);
565 bio_list_add(&list, bio);
566
567 for_each_sg(task->task_sg, sg, task->task_sg_nents, i) {
568 /*
569 * XXX: if the length the device accepts is shorter than the
570 * length of the S/G list entry this will cause and
571 * endless loop. Better hope no driver uses huge pages.
572 */
573 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
574 != sg->length) {
575 bio = iblock_get_bio(task, block_lba, sg_num);
576 if (!bio)
577 goto fail;
578 bio_list_add(&list, bio);
579 }
580
581 /* Always in 512 byte units for Linux/Block */
582 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
583 sg_num--;
584 }
585
586 blk_start_plug(&plug);
587 while ((bio = bio_list_pop(&list)))
588 submit_bio(rw, bio);
589 blk_finish_plug(&plug);
590
591 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
592
593 fail:
594 while ((bio = bio_list_pop(&list)))
595 bio_put(bio);
596 return PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
597 }
598
599 static u32 iblock_get_device_rev(struct se_device *dev)
600 {
601 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
602 }
603
604 static u32 iblock_get_device_type(struct se_device *dev)
605 {
606 return TYPE_DISK;
607 }
608
609 static sector_t iblock_get_blocks(struct se_device *dev)
610 {
611 struct iblock_dev *ibd = dev->dev_ptr;
612 struct block_device *bd = ibd->ibd_bd;
613 struct request_queue *q = bdev_get_queue(bd);
614
615 return iblock_emulate_read_cap_with_block_size(dev, bd, q);
616 }
617
618 static void iblock_bio_done(struct bio *bio, int err)
619 {
620 struct se_task *task = bio->bi_private;
621 struct iblock_req *ibr = IBLOCK_REQ(task);
622
623 /*
624 * Set -EIO if !BIO_UPTODATE and the passed is still err=0
625 */
626 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
627 err = -EIO;
628
629 if (err != 0) {
630 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
631 " err: %d\n", bio, err);
632 /*
633 * Bump the ib_bio_err_cnt and release bio.
634 */
635 atomic_inc(&ibr->ib_bio_err_cnt);
636 smp_mb__after_atomic_inc();
637 }
638
639 bio_put(bio);
640
641 if (!atomic_dec_and_test(&ibr->ib_bio_cnt))
642 return;
643
644 pr_debug("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n",
645 task, bio, task->task_lba,
646 (unsigned long long)bio->bi_sector, err);
647
648 transport_complete_task(task, !atomic_read(&ibr->ib_bio_err_cnt));
649 }
650
651 static struct se_subsystem_api iblock_template = {
652 .name = "iblock",
653 .owner = THIS_MODULE,
654 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
655 .write_cache_emulated = 1,
656 .fua_write_emulated = 1,
657 .attach_hba = iblock_attach_hba,
658 .detach_hba = iblock_detach_hba,
659 .allocate_virtdevice = iblock_allocate_virtdevice,
660 .create_virtdevice = iblock_create_virtdevice,
661 .free_device = iblock_free_device,
662 .alloc_task = iblock_alloc_task,
663 .do_task = iblock_do_task,
664 .do_discard = iblock_do_discard,
665 .do_sync_cache = iblock_emulate_sync_cache,
666 .free_task = iblock_free_task,
667 .check_configfs_dev_params = iblock_check_configfs_dev_params,
668 .set_configfs_dev_params = iblock_set_configfs_dev_params,
669 .show_configfs_dev_params = iblock_show_configfs_dev_params,
670 .get_device_rev = iblock_get_device_rev,
671 .get_device_type = iblock_get_device_type,
672 .get_blocks = iblock_get_blocks,
673 };
674
675 static int __init iblock_module_init(void)
676 {
677 return transport_subsystem_register(&iblock_template);
678 }
679
680 static void iblock_module_exit(void)
681 {
682 transport_subsystem_release(&iblock_template);
683 }
684
685 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
686 MODULE_AUTHOR("nab@Linux-iSCSI.org");
687 MODULE_LICENSE("GPL");
688
689 module_init(iblock_module_init);
690 module_exit(iblock_module_exit);