Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. | |
2b06cfff | 3 | * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include "dm.h" | |
9 | #include "dm-bio-list.h" | |
51e5b2bd | 10 | #include "dm-uevent.h" |
1da177e4 LT |
11 | |
12 | #include <linux/init.h> | |
13 | #include <linux/module.h> | |
48c9c27b | 14 | #include <linux/mutex.h> |
1da177e4 LT |
15 | #include <linux/moduleparam.h> |
16 | #include <linux/blkpg.h> | |
17 | #include <linux/bio.h> | |
18 | #include <linux/buffer_head.h> | |
19 | #include <linux/mempool.h> | |
20 | #include <linux/slab.h> | |
21 | #include <linux/idr.h> | |
3ac51e74 | 22 | #include <linux/hdreg.h> |
2056a782 | 23 | #include <linux/blktrace_api.h> |
aa129a22 | 24 | #include <linux/smp_lock.h> |
1da177e4 | 25 | |
72d94861 AK |
26 | #define DM_MSG_PREFIX "core" |
27 | ||
1da177e4 LT |
28 | static const char *_name = DM_NAME; |
29 | ||
30 | static unsigned int major = 0; | |
31 | static unsigned int _major = 0; | |
32 | ||
f32c10b0 | 33 | static DEFINE_SPINLOCK(_minor_lock); |
1da177e4 LT |
34 | /* |
35 | * One of these is allocated per bio. | |
36 | */ | |
37 | struct dm_io { | |
38 | struct mapped_device *md; | |
39 | int error; | |
1da177e4 | 40 | atomic_t io_count; |
6ae2fa67 | 41 | struct bio *bio; |
3eaf840e | 42 | unsigned long start_time; |
1da177e4 LT |
43 | }; |
44 | ||
45 | /* | |
46 | * One of these is allocated per target within a bio. Hopefully | |
47 | * this will be simplified out one day. | |
48 | */ | |
028867ac | 49 | struct dm_target_io { |
1da177e4 LT |
50 | struct dm_io *io; |
51 | struct dm_target *ti; | |
52 | union map_info info; | |
53 | }; | |
54 | ||
55 | union map_info *dm_get_mapinfo(struct bio *bio) | |
56 | { | |
17b2f66f | 57 | if (bio && bio->bi_private) |
028867ac | 58 | return &((struct dm_target_io *)bio->bi_private)->info; |
17b2f66f | 59 | return NULL; |
1da177e4 LT |
60 | } |
61 | ||
ba61fdd1 JM |
62 | #define MINOR_ALLOCED ((void *)-1) |
63 | ||
1da177e4 LT |
64 | /* |
65 | * Bits for the md->flags field. | |
66 | */ | |
67 | #define DMF_BLOCK_IO 0 | |
68 | #define DMF_SUSPENDED 1 | |
aa8d7c2f | 69 | #define DMF_FROZEN 2 |
fba9f90e | 70 | #define DMF_FREEING 3 |
5c6bd75d | 71 | #define DMF_DELETING 4 |
2e93ccc1 | 72 | #define DMF_NOFLUSH_SUSPENDING 5 |
1da177e4 | 73 | |
304f3f6a MB |
74 | /* |
75 | * Work processed by per-device workqueue. | |
76 | */ | |
77 | struct dm_wq_req { | |
78 | enum { | |
79 | DM_WQ_FLUSH_ALL, | |
80 | DM_WQ_FLUSH_DEFERRED, | |
81 | } type; | |
82 | struct work_struct work; | |
83 | struct mapped_device *md; | |
84 | void *context; | |
85 | }; | |
86 | ||
1da177e4 | 87 | struct mapped_device { |
2ca3310e | 88 | struct rw_semaphore io_lock; |
e61290a4 | 89 | struct mutex suspend_lock; |
2e93ccc1 | 90 | spinlock_t pushback_lock; |
1da177e4 LT |
91 | rwlock_t map_lock; |
92 | atomic_t holders; | |
5c6bd75d | 93 | atomic_t open_count; |
1da177e4 LT |
94 | |
95 | unsigned long flags; | |
96 | ||
165125e1 | 97 | struct request_queue *queue; |
1da177e4 | 98 | struct gendisk *disk; |
7e51f257 | 99 | char name[16]; |
1da177e4 LT |
100 | |
101 | void *interface_ptr; | |
102 | ||
103 | /* | |
104 | * A list of ios that arrived while we were suspended. | |
105 | */ | |
106 | atomic_t pending; | |
107 | wait_queue_head_t wait; | |
74859364 | 108 | struct bio_list deferred; |
2e93ccc1 | 109 | struct bio_list pushback; |
1da177e4 | 110 | |
304f3f6a MB |
111 | /* |
112 | * Processing queue (flush/barriers) | |
113 | */ | |
114 | struct workqueue_struct *wq; | |
115 | ||
1da177e4 LT |
116 | /* |
117 | * The current mapping. | |
118 | */ | |
119 | struct dm_table *map; | |
120 | ||
121 | /* | |
122 | * io objects are allocated from here. | |
123 | */ | |
124 | mempool_t *io_pool; | |
125 | mempool_t *tio_pool; | |
126 | ||
9faf400f SB |
127 | struct bio_set *bs; |
128 | ||
1da177e4 LT |
129 | /* |
130 | * Event handling. | |
131 | */ | |
132 | atomic_t event_nr; | |
133 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
134 | atomic_t uevent_seq; |
135 | struct list_head uevent_list; | |
136 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
137 | |
138 | /* | |
139 | * freeze/thaw support require holding onto a super block | |
140 | */ | |
141 | struct super_block *frozen_sb; | |
e39e2e95 | 142 | struct block_device *suspended_bdev; |
3ac51e74 DW |
143 | |
144 | /* forced geometry settings */ | |
145 | struct hd_geometry geometry; | |
1da177e4 LT |
146 | }; |
147 | ||
148 | #define MIN_IOS 256 | |
e18b890b CL |
149 | static struct kmem_cache *_io_cache; |
150 | static struct kmem_cache *_tio_cache; | |
1da177e4 | 151 | |
1da177e4 LT |
152 | static int __init local_init(void) |
153 | { | |
154 | int r; | |
155 | ||
1da177e4 | 156 | /* allocate a slab for the dm_ios */ |
028867ac | 157 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 LT |
158 | if (!_io_cache) |
159 | return -ENOMEM; | |
160 | ||
161 | /* allocate a slab for the target ios */ | |
028867ac | 162 | _tio_cache = KMEM_CACHE(dm_target_io, 0); |
1da177e4 LT |
163 | if (!_tio_cache) { |
164 | kmem_cache_destroy(_io_cache); | |
165 | return -ENOMEM; | |
166 | } | |
167 | ||
51e5b2bd MA |
168 | r = dm_uevent_init(); |
169 | if (r) { | |
170 | kmem_cache_destroy(_tio_cache); | |
171 | kmem_cache_destroy(_io_cache); | |
172 | return r; | |
173 | } | |
174 | ||
1da177e4 LT |
175 | _major = major; |
176 | r = register_blkdev(_major, _name); | |
177 | if (r < 0) { | |
178 | kmem_cache_destroy(_tio_cache); | |
179 | kmem_cache_destroy(_io_cache); | |
51e5b2bd | 180 | dm_uevent_exit(); |
1da177e4 LT |
181 | return r; |
182 | } | |
183 | ||
184 | if (!_major) | |
185 | _major = r; | |
186 | ||
187 | return 0; | |
188 | } | |
189 | ||
190 | static void local_exit(void) | |
191 | { | |
192 | kmem_cache_destroy(_tio_cache); | |
193 | kmem_cache_destroy(_io_cache); | |
00d59405 | 194 | unregister_blkdev(_major, _name); |
51e5b2bd | 195 | dm_uevent_exit(); |
1da177e4 LT |
196 | |
197 | _major = 0; | |
198 | ||
199 | DMINFO("cleaned up"); | |
200 | } | |
201 | ||
b9249e55 | 202 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
203 | local_init, |
204 | dm_target_init, | |
205 | dm_linear_init, | |
206 | dm_stripe_init, | |
945fa4d2 | 207 | dm_kcopyd_init, |
1da177e4 LT |
208 | dm_interface_init, |
209 | }; | |
210 | ||
b9249e55 | 211 | static void (*_exits[])(void) = { |
1da177e4 LT |
212 | local_exit, |
213 | dm_target_exit, | |
214 | dm_linear_exit, | |
215 | dm_stripe_exit, | |
945fa4d2 | 216 | dm_kcopyd_exit, |
1da177e4 LT |
217 | dm_interface_exit, |
218 | }; | |
219 | ||
220 | static int __init dm_init(void) | |
221 | { | |
222 | const int count = ARRAY_SIZE(_inits); | |
223 | ||
224 | int r, i; | |
225 | ||
226 | for (i = 0; i < count; i++) { | |
227 | r = _inits[i](); | |
228 | if (r) | |
229 | goto bad; | |
230 | } | |
231 | ||
232 | return 0; | |
233 | ||
234 | bad: | |
235 | while (i--) | |
236 | _exits[i](); | |
237 | ||
238 | return r; | |
239 | } | |
240 | ||
241 | static void __exit dm_exit(void) | |
242 | { | |
243 | int i = ARRAY_SIZE(_exits); | |
244 | ||
245 | while (i--) | |
246 | _exits[i](); | |
247 | } | |
248 | ||
249 | /* | |
250 | * Block device functions | |
251 | */ | |
252 | static int dm_blk_open(struct inode *inode, struct file *file) | |
253 | { | |
254 | struct mapped_device *md; | |
255 | ||
fba9f90e JM |
256 | spin_lock(&_minor_lock); |
257 | ||
1da177e4 | 258 | md = inode->i_bdev->bd_disk->private_data; |
fba9f90e JM |
259 | if (!md) |
260 | goto out; | |
261 | ||
5c6bd75d AK |
262 | if (test_bit(DMF_FREEING, &md->flags) || |
263 | test_bit(DMF_DELETING, &md->flags)) { | |
fba9f90e JM |
264 | md = NULL; |
265 | goto out; | |
266 | } | |
267 | ||
1da177e4 | 268 | dm_get(md); |
5c6bd75d | 269 | atomic_inc(&md->open_count); |
fba9f90e JM |
270 | |
271 | out: | |
272 | spin_unlock(&_minor_lock); | |
273 | ||
274 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
275 | } |
276 | ||
277 | static int dm_blk_close(struct inode *inode, struct file *file) | |
278 | { | |
279 | struct mapped_device *md; | |
280 | ||
281 | md = inode->i_bdev->bd_disk->private_data; | |
5c6bd75d | 282 | atomic_dec(&md->open_count); |
1da177e4 LT |
283 | dm_put(md); |
284 | return 0; | |
285 | } | |
286 | ||
5c6bd75d AK |
287 | int dm_open_count(struct mapped_device *md) |
288 | { | |
289 | return atomic_read(&md->open_count); | |
290 | } | |
291 | ||
292 | /* | |
293 | * Guarantees nothing is using the device before it's deleted. | |
294 | */ | |
295 | int dm_lock_for_deletion(struct mapped_device *md) | |
296 | { | |
297 | int r = 0; | |
298 | ||
299 | spin_lock(&_minor_lock); | |
300 | ||
301 | if (dm_open_count(md)) | |
302 | r = -EBUSY; | |
303 | else | |
304 | set_bit(DMF_DELETING, &md->flags); | |
305 | ||
306 | spin_unlock(&_minor_lock); | |
307 | ||
308 | return r; | |
309 | } | |
310 | ||
3ac51e74 DW |
311 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
312 | { | |
313 | struct mapped_device *md = bdev->bd_disk->private_data; | |
314 | ||
315 | return dm_get_geometry(md, geo); | |
316 | } | |
317 | ||
aa129a22 MB |
318 | static int dm_blk_ioctl(struct inode *inode, struct file *file, |
319 | unsigned int cmd, unsigned long arg) | |
320 | { | |
321 | struct mapped_device *md; | |
322 | struct dm_table *map; | |
323 | struct dm_target *tgt; | |
324 | int r = -ENOTTY; | |
325 | ||
326 | /* We don't really need this lock, but we do need 'inode'. */ | |
327 | unlock_kernel(); | |
328 | ||
329 | md = inode->i_bdev->bd_disk->private_data; | |
330 | ||
331 | map = dm_get_table(md); | |
332 | ||
333 | if (!map || !dm_table_get_size(map)) | |
334 | goto out; | |
335 | ||
336 | /* We only support devices that have a single target */ | |
337 | if (dm_table_get_num_targets(map) != 1) | |
338 | goto out; | |
339 | ||
340 | tgt = dm_table_get_target(map, 0); | |
341 | ||
342 | if (dm_suspended(md)) { | |
343 | r = -EAGAIN; | |
344 | goto out; | |
345 | } | |
346 | ||
347 | if (tgt->type->ioctl) | |
348 | r = tgt->type->ioctl(tgt, inode, file, cmd, arg); | |
349 | ||
350 | out: | |
351 | dm_table_put(map); | |
352 | ||
353 | lock_kernel(); | |
354 | return r; | |
355 | } | |
356 | ||
028867ac | 357 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
358 | { |
359 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
360 | } | |
361 | ||
028867ac | 362 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
363 | { |
364 | mempool_free(io, md->io_pool); | |
365 | } | |
366 | ||
028867ac | 367 | static struct dm_target_io *alloc_tio(struct mapped_device *md) |
1da177e4 LT |
368 | { |
369 | return mempool_alloc(md->tio_pool, GFP_NOIO); | |
370 | } | |
371 | ||
028867ac | 372 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 LT |
373 | { |
374 | mempool_free(tio, md->tio_pool); | |
375 | } | |
376 | ||
3eaf840e JNN |
377 | static void start_io_acct(struct dm_io *io) |
378 | { | |
379 | struct mapped_device *md = io->md; | |
380 | ||
381 | io->start_time = jiffies; | |
382 | ||
383 | preempt_disable(); | |
384 | disk_round_stats(dm_disk(md)); | |
385 | preempt_enable(); | |
386 | dm_disk(md)->in_flight = atomic_inc_return(&md->pending); | |
387 | } | |
388 | ||
389 | static int end_io_acct(struct dm_io *io) | |
390 | { | |
391 | struct mapped_device *md = io->md; | |
392 | struct bio *bio = io->bio; | |
393 | unsigned long duration = jiffies - io->start_time; | |
394 | int pending; | |
395 | int rw = bio_data_dir(bio); | |
396 | ||
397 | preempt_disable(); | |
398 | disk_round_stats(dm_disk(md)); | |
399 | preempt_enable(); | |
400 | dm_disk(md)->in_flight = pending = atomic_dec_return(&md->pending); | |
401 | ||
402 | disk_stat_add(dm_disk(md), ticks[rw], duration); | |
403 | ||
404 | return !pending; | |
405 | } | |
406 | ||
1da177e4 LT |
407 | /* |
408 | * Add the bio to the list of deferred io. | |
409 | */ | |
410 | static int queue_io(struct mapped_device *md, struct bio *bio) | |
411 | { | |
2ca3310e | 412 | down_write(&md->io_lock); |
1da177e4 LT |
413 | |
414 | if (!test_bit(DMF_BLOCK_IO, &md->flags)) { | |
2ca3310e | 415 | up_write(&md->io_lock); |
1da177e4 LT |
416 | return 1; |
417 | } | |
418 | ||
419 | bio_list_add(&md->deferred, bio); | |
420 | ||
2ca3310e | 421 | up_write(&md->io_lock); |
1da177e4 LT |
422 | return 0; /* deferred successfully */ |
423 | } | |
424 | ||
425 | /* | |
426 | * Everyone (including functions in this file), should use this | |
427 | * function to access the md->map field, and make sure they call | |
428 | * dm_table_put() when finished. | |
429 | */ | |
430 | struct dm_table *dm_get_table(struct mapped_device *md) | |
431 | { | |
432 | struct dm_table *t; | |
433 | ||
434 | read_lock(&md->map_lock); | |
435 | t = md->map; | |
436 | if (t) | |
437 | dm_table_get(t); | |
438 | read_unlock(&md->map_lock); | |
439 | ||
440 | return t; | |
441 | } | |
442 | ||
3ac51e74 DW |
443 | /* |
444 | * Get the geometry associated with a dm device | |
445 | */ | |
446 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
447 | { | |
448 | *geo = md->geometry; | |
449 | ||
450 | return 0; | |
451 | } | |
452 | ||
453 | /* | |
454 | * Set the geometry of a device. | |
455 | */ | |
456 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
457 | { | |
458 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
459 | ||
460 | if (geo->start > sz) { | |
461 | DMWARN("Start sector is beyond the geometry limits."); | |
462 | return -EINVAL; | |
463 | } | |
464 | ||
465 | md->geometry = *geo; | |
466 | ||
467 | return 0; | |
468 | } | |
469 | ||
1da177e4 LT |
470 | /*----------------------------------------------------------------- |
471 | * CRUD START: | |
472 | * A more elegant soln is in the works that uses the queue | |
473 | * merge fn, unfortunately there are a couple of changes to | |
474 | * the block layer that I want to make for this. So in the | |
475 | * interests of getting something for people to use I give | |
476 | * you this clearly demarcated crap. | |
477 | *---------------------------------------------------------------*/ | |
478 | ||
2e93ccc1 KU |
479 | static int __noflush_suspending(struct mapped_device *md) |
480 | { | |
481 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
482 | } | |
483 | ||
1da177e4 LT |
484 | /* |
485 | * Decrements the number of outstanding ios that a bio has been | |
486 | * cloned into, completing the original io if necc. | |
487 | */ | |
858119e1 | 488 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 489 | { |
2e93ccc1 KU |
490 | unsigned long flags; |
491 | ||
492 | /* Push-back supersedes any I/O errors */ | |
493 | if (error && !(io->error > 0 && __noflush_suspending(io->md))) | |
1da177e4 LT |
494 | io->error = error; |
495 | ||
496 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
497 | if (io->error == DM_ENDIO_REQUEUE) { |
498 | /* | |
499 | * Target requested pushing back the I/O. | |
500 | * This must be handled before the sleeper on | |
501 | * suspend queue merges the pushback list. | |
502 | */ | |
503 | spin_lock_irqsave(&io->md->pushback_lock, flags); | |
504 | if (__noflush_suspending(io->md)) | |
505 | bio_list_add(&io->md->pushback, io->bio); | |
506 | else | |
507 | /* noflush suspend was interrupted. */ | |
508 | io->error = -EIO; | |
509 | spin_unlock_irqrestore(&io->md->pushback_lock, flags); | |
510 | } | |
511 | ||
3eaf840e | 512 | if (end_io_acct(io)) |
1da177e4 LT |
513 | /* nudge anyone waiting on suspend queue */ |
514 | wake_up(&io->md->wait); | |
515 | ||
2e93ccc1 KU |
516 | if (io->error != DM_ENDIO_REQUEUE) { |
517 | blk_add_trace_bio(io->md->queue, io->bio, | |
518 | BLK_TA_COMPLETE); | |
519 | ||
6712ecf8 | 520 | bio_endio(io->bio, io->error); |
2e93ccc1 | 521 | } |
2056a782 | 522 | |
1da177e4 LT |
523 | free_io(io->md, io); |
524 | } | |
525 | } | |
526 | ||
6712ecf8 | 527 | static void clone_endio(struct bio *bio, int error) |
1da177e4 LT |
528 | { |
529 | int r = 0; | |
028867ac | 530 | struct dm_target_io *tio = bio->bi_private; |
9faf400f | 531 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
532 | dm_endio_fn endio = tio->ti->type->end_io; |
533 | ||
1da177e4 LT |
534 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
535 | error = -EIO; | |
536 | ||
537 | if (endio) { | |
538 | r = endio(tio->ti, bio, error, &tio->info); | |
2e93ccc1 KU |
539 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
540 | /* | |
541 | * error and requeue request are handled | |
542 | * in dec_pending(). | |
543 | */ | |
1da177e4 | 544 | error = r; |
45cbcd79 KU |
545 | else if (r == DM_ENDIO_INCOMPLETE) |
546 | /* The target will handle the io */ | |
6712ecf8 | 547 | return; |
45cbcd79 KU |
548 | else if (r) { |
549 | DMWARN("unimplemented target endio return value: %d", r); | |
550 | BUG(); | |
551 | } | |
1da177e4 LT |
552 | } |
553 | ||
9faf400f SB |
554 | dec_pending(tio->io, error); |
555 | ||
556 | /* | |
557 | * Store md for cleanup instead of tio which is about to get freed. | |
558 | */ | |
559 | bio->bi_private = md->bs; | |
560 | ||
1da177e4 | 561 | bio_put(bio); |
9faf400f | 562 | free_tio(md, tio); |
1da177e4 LT |
563 | } |
564 | ||
565 | static sector_t max_io_len(struct mapped_device *md, | |
566 | sector_t sector, struct dm_target *ti) | |
567 | { | |
568 | sector_t offset = sector - ti->begin; | |
569 | sector_t len = ti->len - offset; | |
570 | ||
571 | /* | |
572 | * Does the target need to split even further ? | |
573 | */ | |
574 | if (ti->split_io) { | |
575 | sector_t boundary; | |
576 | boundary = ((offset + ti->split_io) & ~(ti->split_io - 1)) | |
577 | - offset; | |
578 | if (len > boundary) | |
579 | len = boundary; | |
580 | } | |
581 | ||
582 | return len; | |
583 | } | |
584 | ||
585 | static void __map_bio(struct dm_target *ti, struct bio *clone, | |
028867ac | 586 | struct dm_target_io *tio) |
1da177e4 LT |
587 | { |
588 | int r; | |
2056a782 | 589 | sector_t sector; |
9faf400f | 590 | struct mapped_device *md; |
1da177e4 LT |
591 | |
592 | /* | |
593 | * Sanity checks. | |
594 | */ | |
595 | BUG_ON(!clone->bi_size); | |
596 | ||
597 | clone->bi_end_io = clone_endio; | |
598 | clone->bi_private = tio; | |
599 | ||
600 | /* | |
601 | * Map the clone. If r == 0 we don't need to do | |
602 | * anything, the target has assumed ownership of | |
603 | * this io. | |
604 | */ | |
605 | atomic_inc(&tio->io->io_count); | |
2056a782 | 606 | sector = clone->bi_sector; |
1da177e4 | 607 | r = ti->type->map(ti, clone, &tio->info); |
45cbcd79 | 608 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 609 | /* the bio has been remapped so dispatch it */ |
2056a782 | 610 | |
17b2f66f | 611 | blk_add_trace_remap(bdev_get_queue(clone->bi_bdev), clone, |
c7149d6b AB |
612 | tio->io->bio->bi_bdev->bd_dev, |
613 | clone->bi_sector, sector); | |
2056a782 | 614 | |
1da177e4 | 615 | generic_make_request(clone); |
2e93ccc1 KU |
616 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
617 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
618 | md = tio->io->md; |
619 | dec_pending(tio->io, r); | |
620 | /* | |
621 | * Store bio_set for cleanup. | |
622 | */ | |
623 | clone->bi_private = md->bs; | |
1da177e4 | 624 | bio_put(clone); |
9faf400f | 625 | free_tio(md, tio); |
45cbcd79 KU |
626 | } else if (r) { |
627 | DMWARN("unimplemented target map return value: %d", r); | |
628 | BUG(); | |
1da177e4 LT |
629 | } |
630 | } | |
631 | ||
632 | struct clone_info { | |
633 | struct mapped_device *md; | |
634 | struct dm_table *map; | |
635 | struct bio *bio; | |
636 | struct dm_io *io; | |
637 | sector_t sector; | |
638 | sector_t sector_count; | |
639 | unsigned short idx; | |
640 | }; | |
641 | ||
3676347a PO |
642 | static void dm_bio_destructor(struct bio *bio) |
643 | { | |
9faf400f SB |
644 | struct bio_set *bs = bio->bi_private; |
645 | ||
646 | bio_free(bio, bs); | |
3676347a PO |
647 | } |
648 | ||
1da177e4 LT |
649 | /* |
650 | * Creates a little bio that is just does part of a bvec. | |
651 | */ | |
652 | static struct bio *split_bvec(struct bio *bio, sector_t sector, | |
653 | unsigned short idx, unsigned int offset, | |
9faf400f | 654 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
655 | { |
656 | struct bio *clone; | |
657 | struct bio_vec *bv = bio->bi_io_vec + idx; | |
658 | ||
9faf400f | 659 | clone = bio_alloc_bioset(GFP_NOIO, 1, bs); |
3676347a | 660 | clone->bi_destructor = dm_bio_destructor; |
1da177e4 LT |
661 | *clone->bi_io_vec = *bv; |
662 | ||
663 | clone->bi_sector = sector; | |
664 | clone->bi_bdev = bio->bi_bdev; | |
665 | clone->bi_rw = bio->bi_rw; | |
666 | clone->bi_vcnt = 1; | |
667 | clone->bi_size = to_bytes(len); | |
668 | clone->bi_io_vec->bv_offset = offset; | |
669 | clone->bi_io_vec->bv_len = clone->bi_size; | |
670 | ||
671 | return clone; | |
672 | } | |
673 | ||
674 | /* | |
675 | * Creates a bio that consists of range of complete bvecs. | |
676 | */ | |
677 | static struct bio *clone_bio(struct bio *bio, sector_t sector, | |
678 | unsigned short idx, unsigned short bv_count, | |
9faf400f | 679 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
680 | { |
681 | struct bio *clone; | |
682 | ||
9faf400f SB |
683 | clone = bio_alloc_bioset(GFP_NOIO, bio->bi_max_vecs, bs); |
684 | __bio_clone(clone, bio); | |
685 | clone->bi_destructor = dm_bio_destructor; | |
1da177e4 LT |
686 | clone->bi_sector = sector; |
687 | clone->bi_idx = idx; | |
688 | clone->bi_vcnt = idx + bv_count; | |
689 | clone->bi_size = to_bytes(len); | |
690 | clone->bi_flags &= ~(1 << BIO_SEG_VALID); | |
691 | ||
692 | return clone; | |
693 | } | |
694 | ||
512875bd | 695 | static int __clone_and_map(struct clone_info *ci) |
1da177e4 LT |
696 | { |
697 | struct bio *clone, *bio = ci->bio; | |
512875bd JN |
698 | struct dm_target *ti; |
699 | sector_t len = 0, max; | |
028867ac | 700 | struct dm_target_io *tio; |
1da177e4 | 701 | |
512875bd JN |
702 | ti = dm_table_find_target(ci->map, ci->sector); |
703 | if (!dm_target_is_valid(ti)) | |
704 | return -EIO; | |
705 | ||
706 | max = max_io_len(ci->md, ci->sector, ti); | |
707 | ||
1da177e4 LT |
708 | /* |
709 | * Allocate a target io object. | |
710 | */ | |
711 | tio = alloc_tio(ci->md); | |
712 | tio->io = ci->io; | |
713 | tio->ti = ti; | |
714 | memset(&tio->info, 0, sizeof(tio->info)); | |
715 | ||
716 | if (ci->sector_count <= max) { | |
717 | /* | |
718 | * Optimise for the simple case where we can do all of | |
719 | * the remaining io with a single clone. | |
720 | */ | |
721 | clone = clone_bio(bio, ci->sector, ci->idx, | |
9faf400f SB |
722 | bio->bi_vcnt - ci->idx, ci->sector_count, |
723 | ci->md->bs); | |
1da177e4 LT |
724 | __map_bio(ti, clone, tio); |
725 | ci->sector_count = 0; | |
726 | ||
727 | } else if (to_sector(bio->bi_io_vec[ci->idx].bv_len) <= max) { | |
728 | /* | |
729 | * There are some bvecs that don't span targets. | |
730 | * Do as many of these as possible. | |
731 | */ | |
732 | int i; | |
733 | sector_t remaining = max; | |
734 | sector_t bv_len; | |
735 | ||
736 | for (i = ci->idx; remaining && (i < bio->bi_vcnt); i++) { | |
737 | bv_len = to_sector(bio->bi_io_vec[i].bv_len); | |
738 | ||
739 | if (bv_len > remaining) | |
740 | break; | |
741 | ||
742 | remaining -= bv_len; | |
743 | len += bv_len; | |
744 | } | |
745 | ||
9faf400f SB |
746 | clone = clone_bio(bio, ci->sector, ci->idx, i - ci->idx, len, |
747 | ci->md->bs); | |
1da177e4 LT |
748 | __map_bio(ti, clone, tio); |
749 | ||
750 | ci->sector += len; | |
751 | ci->sector_count -= len; | |
752 | ci->idx = i; | |
753 | ||
754 | } else { | |
755 | /* | |
d2044a94 | 756 | * Handle a bvec that must be split between two or more targets. |
1da177e4 LT |
757 | */ |
758 | struct bio_vec *bv = bio->bi_io_vec + ci->idx; | |
d2044a94 AK |
759 | sector_t remaining = to_sector(bv->bv_len); |
760 | unsigned int offset = 0; | |
1da177e4 | 761 | |
d2044a94 AK |
762 | do { |
763 | if (offset) { | |
764 | ti = dm_table_find_target(ci->map, ci->sector); | |
512875bd JN |
765 | if (!dm_target_is_valid(ti)) |
766 | return -EIO; | |
767 | ||
d2044a94 | 768 | max = max_io_len(ci->md, ci->sector, ti); |
1da177e4 | 769 | |
d2044a94 AK |
770 | tio = alloc_tio(ci->md); |
771 | tio->io = ci->io; | |
772 | tio->ti = ti; | |
773 | memset(&tio->info, 0, sizeof(tio->info)); | |
774 | } | |
775 | ||
776 | len = min(remaining, max); | |
777 | ||
778 | clone = split_bvec(bio, ci->sector, ci->idx, | |
9faf400f SB |
779 | bv->bv_offset + offset, len, |
780 | ci->md->bs); | |
d2044a94 AK |
781 | |
782 | __map_bio(ti, clone, tio); | |
783 | ||
784 | ci->sector += len; | |
785 | ci->sector_count -= len; | |
786 | offset += to_bytes(len); | |
787 | } while (remaining -= len); | |
1da177e4 | 788 | |
1da177e4 LT |
789 | ci->idx++; |
790 | } | |
512875bd JN |
791 | |
792 | return 0; | |
1da177e4 LT |
793 | } |
794 | ||
795 | /* | |
796 | * Split the bio into several clones. | |
797 | */ | |
9e4e5f87 | 798 | static int __split_bio(struct mapped_device *md, struct bio *bio) |
1da177e4 LT |
799 | { |
800 | struct clone_info ci; | |
512875bd | 801 | int error = 0; |
1da177e4 LT |
802 | |
803 | ci.map = dm_get_table(md); | |
9e4e5f87 MB |
804 | if (unlikely(!ci.map)) |
805 | return -EIO; | |
1da177e4 LT |
806 | |
807 | ci.md = md; | |
808 | ci.bio = bio; | |
809 | ci.io = alloc_io(md); | |
810 | ci.io->error = 0; | |
811 | atomic_set(&ci.io->io_count, 1); | |
812 | ci.io->bio = bio; | |
813 | ci.io->md = md; | |
814 | ci.sector = bio->bi_sector; | |
815 | ci.sector_count = bio_sectors(bio); | |
816 | ci.idx = bio->bi_idx; | |
817 | ||
3eaf840e | 818 | start_io_acct(ci.io); |
512875bd JN |
819 | while (ci.sector_count && !error) |
820 | error = __clone_and_map(&ci); | |
1da177e4 LT |
821 | |
822 | /* drop the extra reference count */ | |
512875bd | 823 | dec_pending(ci.io, error); |
1da177e4 | 824 | dm_table_put(ci.map); |
9e4e5f87 MB |
825 | |
826 | return 0; | |
1da177e4 LT |
827 | } |
828 | /*----------------------------------------------------------------- | |
829 | * CRUD END | |
830 | *---------------------------------------------------------------*/ | |
831 | ||
f6fccb12 MB |
832 | static int dm_merge_bvec(struct request_queue *q, |
833 | struct bvec_merge_data *bvm, | |
834 | struct bio_vec *biovec) | |
835 | { | |
836 | struct mapped_device *md = q->queuedata; | |
837 | struct dm_table *map = dm_get_table(md); | |
838 | struct dm_target *ti; | |
839 | sector_t max_sectors; | |
5037108a | 840 | int max_size = 0; |
f6fccb12 MB |
841 | |
842 | if (unlikely(!map)) | |
5037108a | 843 | goto out; |
f6fccb12 MB |
844 | |
845 | ti = dm_table_find_target(map, bvm->bi_sector); | |
846 | ||
847 | /* | |
848 | * Find maximum amount of I/O that won't need splitting | |
849 | */ | |
850 | max_sectors = min(max_io_len(md, bvm->bi_sector, ti), | |
851 | (sector_t) BIO_MAX_SECTORS); | |
852 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; | |
853 | if (max_size < 0) | |
854 | max_size = 0; | |
855 | ||
856 | /* | |
857 | * merge_bvec_fn() returns number of bytes | |
858 | * it can accept at this offset | |
859 | * max is precomputed maximal io size | |
860 | */ | |
861 | if (max_size && ti->type->merge) | |
862 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
863 | ||
5037108a MP |
864 | dm_table_put(map); |
865 | ||
866 | out: | |
f6fccb12 MB |
867 | /* |
868 | * Always allow an entire first page | |
869 | */ | |
870 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
871 | max_size = biovec->bv_len; | |
872 | ||
f6fccb12 MB |
873 | return max_size; |
874 | } | |
875 | ||
1da177e4 LT |
876 | /* |
877 | * The request function that just remaps the bio built up by | |
878 | * dm_merge_bvec. | |
879 | */ | |
165125e1 | 880 | static int dm_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 881 | { |
9e4e5f87 | 882 | int r = -EIO; |
12f03a49 | 883 | int rw = bio_data_dir(bio); |
1da177e4 LT |
884 | struct mapped_device *md = q->queuedata; |
885 | ||
07a83c47 SB |
886 | /* |
887 | * There is no use in forwarding any barrier request since we can't | |
888 | * guarantee it is (or can be) handled by the targets correctly. | |
889 | */ | |
890 | if (unlikely(bio_barrier(bio))) { | |
6712ecf8 | 891 | bio_endio(bio, -EOPNOTSUPP); |
07a83c47 SB |
892 | return 0; |
893 | } | |
894 | ||
2ca3310e | 895 | down_read(&md->io_lock); |
1da177e4 | 896 | |
12f03a49 KC |
897 | disk_stat_inc(dm_disk(md), ios[rw]); |
898 | disk_stat_add(dm_disk(md), sectors[rw], bio_sectors(bio)); | |
899 | ||
1da177e4 LT |
900 | /* |
901 | * If we're suspended we have to queue | |
902 | * this io for later. | |
903 | */ | |
904 | while (test_bit(DMF_BLOCK_IO, &md->flags)) { | |
2ca3310e | 905 | up_read(&md->io_lock); |
1da177e4 | 906 | |
9e4e5f87 MB |
907 | if (bio_rw(bio) != READA) |
908 | r = queue_io(md, bio); | |
1da177e4 | 909 | |
9e4e5f87 MB |
910 | if (r <= 0) |
911 | goto out_req; | |
1da177e4 LT |
912 | |
913 | /* | |
914 | * We're in a while loop, because someone could suspend | |
915 | * before we get to the following read lock. | |
916 | */ | |
2ca3310e | 917 | down_read(&md->io_lock); |
1da177e4 LT |
918 | } |
919 | ||
9e4e5f87 | 920 | r = __split_bio(md, bio); |
2ca3310e | 921 | up_read(&md->io_lock); |
9e4e5f87 MB |
922 | |
923 | out_req: | |
924 | if (r < 0) | |
925 | bio_io_error(bio); | |
926 | ||
1da177e4 LT |
927 | return 0; |
928 | } | |
929 | ||
165125e1 | 930 | static void dm_unplug_all(struct request_queue *q) |
1da177e4 LT |
931 | { |
932 | struct mapped_device *md = q->queuedata; | |
933 | struct dm_table *map = dm_get_table(md); | |
934 | ||
935 | if (map) { | |
936 | dm_table_unplug_all(map); | |
937 | dm_table_put(map); | |
938 | } | |
939 | } | |
940 | ||
941 | static int dm_any_congested(void *congested_data, int bdi_bits) | |
942 | { | |
943 | int r; | |
944 | struct mapped_device *md = (struct mapped_device *) congested_data; | |
945 | struct dm_table *map = dm_get_table(md); | |
946 | ||
947 | if (!map || test_bit(DMF_BLOCK_IO, &md->flags)) | |
948 | r = bdi_bits; | |
949 | else | |
950 | r = dm_table_any_congested(map, bdi_bits); | |
951 | ||
952 | dm_table_put(map); | |
953 | return r; | |
954 | } | |
955 | ||
956 | /*----------------------------------------------------------------- | |
957 | * An IDR is used to keep track of allocated minor numbers. | |
958 | *---------------------------------------------------------------*/ | |
1da177e4 LT |
959 | static DEFINE_IDR(_minor_idr); |
960 | ||
2b06cfff | 961 | static void free_minor(int minor) |
1da177e4 | 962 | { |
f32c10b0 | 963 | spin_lock(&_minor_lock); |
1da177e4 | 964 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 965 | spin_unlock(&_minor_lock); |
1da177e4 LT |
966 | } |
967 | ||
968 | /* | |
969 | * See if the device with a specific minor # is free. | |
970 | */ | |
cf13ab8e | 971 | static int specific_minor(int minor) |
1da177e4 LT |
972 | { |
973 | int r, m; | |
974 | ||
975 | if (minor >= (1 << MINORBITS)) | |
976 | return -EINVAL; | |
977 | ||
62f75c2f JM |
978 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
979 | if (!r) | |
980 | return -ENOMEM; | |
981 | ||
f32c10b0 | 982 | spin_lock(&_minor_lock); |
1da177e4 LT |
983 | |
984 | if (idr_find(&_minor_idr, minor)) { | |
985 | r = -EBUSY; | |
986 | goto out; | |
987 | } | |
988 | ||
ba61fdd1 | 989 | r = idr_get_new_above(&_minor_idr, MINOR_ALLOCED, minor, &m); |
62f75c2f | 990 | if (r) |
1da177e4 | 991 | goto out; |
1da177e4 LT |
992 | |
993 | if (m != minor) { | |
994 | idr_remove(&_minor_idr, m); | |
995 | r = -EBUSY; | |
996 | goto out; | |
997 | } | |
998 | ||
999 | out: | |
f32c10b0 | 1000 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1001 | return r; |
1002 | } | |
1003 | ||
cf13ab8e | 1004 | static int next_free_minor(int *minor) |
1da177e4 | 1005 | { |
2b06cfff | 1006 | int r, m; |
1da177e4 | 1007 | |
1da177e4 | 1008 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
62f75c2f JM |
1009 | if (!r) |
1010 | return -ENOMEM; | |
1011 | ||
f32c10b0 | 1012 | spin_lock(&_minor_lock); |
1da177e4 | 1013 | |
ba61fdd1 | 1014 | r = idr_get_new(&_minor_idr, MINOR_ALLOCED, &m); |
cf13ab8e | 1015 | if (r) |
1da177e4 | 1016 | goto out; |
1da177e4 LT |
1017 | |
1018 | if (m >= (1 << MINORBITS)) { | |
1019 | idr_remove(&_minor_idr, m); | |
1020 | r = -ENOSPC; | |
1021 | goto out; | |
1022 | } | |
1023 | ||
1024 | *minor = m; | |
1025 | ||
1026 | out: | |
f32c10b0 | 1027 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1028 | return r; |
1029 | } | |
1030 | ||
1031 | static struct block_device_operations dm_blk_dops; | |
1032 | ||
1033 | /* | |
1034 | * Allocate and initialise a blank device with a given minor. | |
1035 | */ | |
2b06cfff | 1036 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
1037 | { |
1038 | int r; | |
cf13ab8e | 1039 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 1040 | void *old_md; |
1da177e4 LT |
1041 | |
1042 | if (!md) { | |
1043 | DMWARN("unable to allocate device, out of memory."); | |
1044 | return NULL; | |
1045 | } | |
1046 | ||
10da4f79 | 1047 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 1048 | goto bad_module_get; |
10da4f79 | 1049 | |
1da177e4 | 1050 | /* get a minor number for the dev */ |
2b06cfff | 1051 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 1052 | r = next_free_minor(&minor); |
2b06cfff | 1053 | else |
cf13ab8e | 1054 | r = specific_minor(minor); |
1da177e4 | 1055 | if (r < 0) |
6ed7ade8 | 1056 | goto bad_minor; |
1da177e4 | 1057 | |
2ca3310e | 1058 | init_rwsem(&md->io_lock); |
e61290a4 | 1059 | mutex_init(&md->suspend_lock); |
2e93ccc1 | 1060 | spin_lock_init(&md->pushback_lock); |
1da177e4 LT |
1061 | rwlock_init(&md->map_lock); |
1062 | atomic_set(&md->holders, 1); | |
5c6bd75d | 1063 | atomic_set(&md->open_count, 0); |
1da177e4 | 1064 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
1065 | atomic_set(&md->uevent_seq, 0); |
1066 | INIT_LIST_HEAD(&md->uevent_list); | |
1067 | spin_lock_init(&md->uevent_lock); | |
1da177e4 LT |
1068 | |
1069 | md->queue = blk_alloc_queue(GFP_KERNEL); | |
1070 | if (!md->queue) | |
6ed7ade8 | 1071 | goto bad_queue; |
1da177e4 LT |
1072 | |
1073 | md->queue->queuedata = md; | |
1074 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
1075 | md->queue->backing_dev_info.congested_data = md; | |
1076 | blk_queue_make_request(md->queue, dm_request); | |
daef265f | 1077 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); |
1da177e4 | 1078 | md->queue->unplug_fn = dm_unplug_all; |
f6fccb12 | 1079 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); |
1da177e4 | 1080 | |
93d2341c | 1081 | md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache); |
74859364 | 1082 | if (!md->io_pool) |
6ed7ade8 | 1083 | goto bad_io_pool; |
1da177e4 | 1084 | |
93d2341c | 1085 | md->tio_pool = mempool_create_slab_pool(MIN_IOS, _tio_cache); |
1da177e4 | 1086 | if (!md->tio_pool) |
6ed7ade8 | 1087 | goto bad_tio_pool; |
1da177e4 | 1088 | |
5972511b | 1089 | md->bs = bioset_create(16, 16); |
9faf400f SB |
1090 | if (!md->bs) |
1091 | goto bad_no_bioset; | |
1092 | ||
1da177e4 LT |
1093 | md->disk = alloc_disk(1); |
1094 | if (!md->disk) | |
6ed7ade8 | 1095 | goto bad_disk; |
1da177e4 | 1096 | |
f0b04115 JM |
1097 | atomic_set(&md->pending, 0); |
1098 | init_waitqueue_head(&md->wait); | |
1099 | init_waitqueue_head(&md->eventq); | |
1100 | ||
1da177e4 LT |
1101 | md->disk->major = _major; |
1102 | md->disk->first_minor = minor; | |
1103 | md->disk->fops = &dm_blk_dops; | |
1104 | md->disk->queue = md->queue; | |
1105 | md->disk->private_data = md; | |
1106 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
1107 | add_disk(md->disk); | |
7e51f257 | 1108 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 1109 | |
304f3f6a MB |
1110 | md->wq = create_singlethread_workqueue("kdmflush"); |
1111 | if (!md->wq) | |
1112 | goto bad_thread; | |
1113 | ||
ba61fdd1 | 1114 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 1115 | spin_lock(&_minor_lock); |
ba61fdd1 | 1116 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 1117 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
1118 | |
1119 | BUG_ON(old_md != MINOR_ALLOCED); | |
1120 | ||
1da177e4 LT |
1121 | return md; |
1122 | ||
304f3f6a MB |
1123 | bad_thread: |
1124 | put_disk(md->disk); | |
6ed7ade8 | 1125 | bad_disk: |
9faf400f | 1126 | bioset_free(md->bs); |
6ed7ade8 | 1127 | bad_no_bioset: |
1da177e4 | 1128 | mempool_destroy(md->tio_pool); |
6ed7ade8 | 1129 | bad_tio_pool: |
1da177e4 | 1130 | mempool_destroy(md->io_pool); |
6ed7ade8 | 1131 | bad_io_pool: |
1312f40e | 1132 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 1133 | bad_queue: |
1da177e4 | 1134 | free_minor(minor); |
6ed7ade8 | 1135 | bad_minor: |
10da4f79 | 1136 | module_put(THIS_MODULE); |
6ed7ade8 | 1137 | bad_module_get: |
1da177e4 LT |
1138 | kfree(md); |
1139 | return NULL; | |
1140 | } | |
1141 | ||
ae9da83f JN |
1142 | static void unlock_fs(struct mapped_device *md); |
1143 | ||
1da177e4 LT |
1144 | static void free_dev(struct mapped_device *md) |
1145 | { | |
2b06cfff | 1146 | int minor = md->disk->first_minor; |
63d94e48 | 1147 | |
d9dde59b | 1148 | if (md->suspended_bdev) { |
ae9da83f | 1149 | unlock_fs(md); |
d9dde59b JN |
1150 | bdput(md->suspended_bdev); |
1151 | } | |
304f3f6a | 1152 | destroy_workqueue(md->wq); |
1da177e4 LT |
1153 | mempool_destroy(md->tio_pool); |
1154 | mempool_destroy(md->io_pool); | |
9faf400f | 1155 | bioset_free(md->bs); |
1da177e4 | 1156 | del_gendisk(md->disk); |
63d94e48 | 1157 | free_minor(minor); |
fba9f90e JM |
1158 | |
1159 | spin_lock(&_minor_lock); | |
1160 | md->disk->private_data = NULL; | |
1161 | spin_unlock(&_minor_lock); | |
1162 | ||
1da177e4 | 1163 | put_disk(md->disk); |
1312f40e | 1164 | blk_cleanup_queue(md->queue); |
10da4f79 | 1165 | module_put(THIS_MODULE); |
1da177e4 LT |
1166 | kfree(md); |
1167 | } | |
1168 | ||
1169 | /* | |
1170 | * Bind a table to the device. | |
1171 | */ | |
1172 | static void event_callback(void *context) | |
1173 | { | |
7a8c3d3b MA |
1174 | unsigned long flags; |
1175 | LIST_HEAD(uevents); | |
1da177e4 LT |
1176 | struct mapped_device *md = (struct mapped_device *) context; |
1177 | ||
7a8c3d3b MA |
1178 | spin_lock_irqsave(&md->uevent_lock, flags); |
1179 | list_splice_init(&md->uevent_list, &uevents); | |
1180 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
1181 | ||
edfaa7c3 | 1182 | dm_send_uevents(&uevents, &md->disk->dev.kobj); |
7a8c3d3b | 1183 | |
1da177e4 LT |
1184 | atomic_inc(&md->event_nr); |
1185 | wake_up(&md->eventq); | |
1186 | } | |
1187 | ||
4e90188b | 1188 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 1189 | { |
4e90188b | 1190 | set_capacity(md->disk, size); |
1da177e4 | 1191 | |
1b1dcc1b | 1192 | mutex_lock(&md->suspended_bdev->bd_inode->i_mutex); |
e39e2e95 | 1193 | i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
1b1dcc1b | 1194 | mutex_unlock(&md->suspended_bdev->bd_inode->i_mutex); |
1da177e4 LT |
1195 | } |
1196 | ||
1197 | static int __bind(struct mapped_device *md, struct dm_table *t) | |
1198 | { | |
165125e1 | 1199 | struct request_queue *q = md->queue; |
1da177e4 LT |
1200 | sector_t size; |
1201 | ||
1202 | size = dm_table_get_size(t); | |
3ac51e74 DW |
1203 | |
1204 | /* | |
1205 | * Wipe any geometry if the size of the table changed. | |
1206 | */ | |
1207 | if (size != get_capacity(md->disk)) | |
1208 | memset(&md->geometry, 0, sizeof(md->geometry)); | |
1209 | ||
bfa152fa JN |
1210 | if (md->suspended_bdev) |
1211 | __set_size(md, size); | |
1da177e4 LT |
1212 | if (size == 0) |
1213 | return 0; | |
1214 | ||
2ca3310e AK |
1215 | dm_table_get(t); |
1216 | dm_table_event_callback(t, event_callback, md); | |
1217 | ||
1da177e4 LT |
1218 | write_lock(&md->map_lock); |
1219 | md->map = t; | |
2ca3310e | 1220 | dm_table_set_restrictions(t, q); |
1da177e4 LT |
1221 | write_unlock(&md->map_lock); |
1222 | ||
1da177e4 LT |
1223 | return 0; |
1224 | } | |
1225 | ||
1226 | static void __unbind(struct mapped_device *md) | |
1227 | { | |
1228 | struct dm_table *map = md->map; | |
1229 | ||
1230 | if (!map) | |
1231 | return; | |
1232 | ||
1233 | dm_table_event_callback(map, NULL, NULL); | |
1234 | write_lock(&md->map_lock); | |
1235 | md->map = NULL; | |
1236 | write_unlock(&md->map_lock); | |
1237 | dm_table_put(map); | |
1238 | } | |
1239 | ||
1240 | /* | |
1241 | * Constructor for a new device. | |
1242 | */ | |
2b06cfff | 1243 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
1244 | { |
1245 | struct mapped_device *md; | |
1246 | ||
2b06cfff | 1247 | md = alloc_dev(minor); |
1da177e4 LT |
1248 | if (!md) |
1249 | return -ENXIO; | |
1250 | ||
1251 | *result = md; | |
1252 | return 0; | |
1253 | } | |
1254 | ||
637842cf | 1255 | static struct mapped_device *dm_find_md(dev_t dev) |
1da177e4 LT |
1256 | { |
1257 | struct mapped_device *md; | |
1da177e4 LT |
1258 | unsigned minor = MINOR(dev); |
1259 | ||
1260 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
1261 | return NULL; | |
1262 | ||
f32c10b0 | 1263 | spin_lock(&_minor_lock); |
1da177e4 LT |
1264 | |
1265 | md = idr_find(&_minor_idr, minor); | |
fba9f90e JM |
1266 | if (md && (md == MINOR_ALLOCED || |
1267 | (dm_disk(md)->first_minor != minor) || | |
17b2f66f | 1268 | test_bit(DMF_FREEING, &md->flags))) { |
637842cf | 1269 | md = NULL; |
fba9f90e JM |
1270 | goto out; |
1271 | } | |
1da177e4 | 1272 | |
fba9f90e | 1273 | out: |
f32c10b0 | 1274 | spin_unlock(&_minor_lock); |
1da177e4 | 1275 | |
637842cf DT |
1276 | return md; |
1277 | } | |
1278 | ||
d229a958 DT |
1279 | struct mapped_device *dm_get_md(dev_t dev) |
1280 | { | |
1281 | struct mapped_device *md = dm_find_md(dev); | |
1282 | ||
1283 | if (md) | |
1284 | dm_get(md); | |
1285 | ||
1286 | return md; | |
1287 | } | |
1288 | ||
9ade92a9 | 1289 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 1290 | { |
9ade92a9 | 1291 | return md->interface_ptr; |
1da177e4 LT |
1292 | } |
1293 | ||
1294 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
1295 | { | |
1296 | md->interface_ptr = ptr; | |
1297 | } | |
1298 | ||
1299 | void dm_get(struct mapped_device *md) | |
1300 | { | |
1301 | atomic_inc(&md->holders); | |
1302 | } | |
1303 | ||
72d94861 AK |
1304 | const char *dm_device_name(struct mapped_device *md) |
1305 | { | |
1306 | return md->name; | |
1307 | } | |
1308 | EXPORT_SYMBOL_GPL(dm_device_name); | |
1309 | ||
1da177e4 LT |
1310 | void dm_put(struct mapped_device *md) |
1311 | { | |
1134e5ae | 1312 | struct dm_table *map; |
1da177e4 | 1313 | |
fba9f90e JM |
1314 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
1315 | ||
f32c10b0 | 1316 | if (atomic_dec_and_lock(&md->holders, &_minor_lock)) { |
1134e5ae | 1317 | map = dm_get_table(md); |
ba61fdd1 | 1318 | idr_replace(&_minor_idr, MINOR_ALLOCED, dm_disk(md)->first_minor); |
fba9f90e | 1319 | set_bit(DMF_FREEING, &md->flags); |
f32c10b0 | 1320 | spin_unlock(&_minor_lock); |
cf222b37 | 1321 | if (!dm_suspended(md)) { |
1da177e4 LT |
1322 | dm_table_presuspend_targets(map); |
1323 | dm_table_postsuspend_targets(map); | |
1324 | } | |
1325 | __unbind(md); | |
1134e5ae | 1326 | dm_table_put(map); |
1da177e4 LT |
1327 | free_dev(md); |
1328 | } | |
1da177e4 | 1329 | } |
79eb885c | 1330 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 1331 | |
46125c1c MB |
1332 | static int dm_wait_for_completion(struct mapped_device *md) |
1333 | { | |
1334 | int r = 0; | |
1335 | ||
1336 | while (1) { | |
1337 | set_current_state(TASK_INTERRUPTIBLE); | |
1338 | ||
1339 | smp_mb(); | |
1340 | if (!atomic_read(&md->pending)) | |
1341 | break; | |
1342 | ||
1343 | if (signal_pending(current)) { | |
1344 | r = -EINTR; | |
1345 | break; | |
1346 | } | |
1347 | ||
1348 | io_schedule(); | |
1349 | } | |
1350 | set_current_state(TASK_RUNNING); | |
1351 | ||
1352 | return r; | |
1353 | } | |
1354 | ||
1da177e4 LT |
1355 | /* |
1356 | * Process the deferred bios | |
1357 | */ | |
6d6f10df | 1358 | static void __flush_deferred_io(struct mapped_device *md) |
1da177e4 | 1359 | { |
6d6f10df | 1360 | struct bio *c; |
1da177e4 | 1361 | |
6d6f10df | 1362 | while ((c = bio_list_pop(&md->deferred))) { |
9e4e5f87 MB |
1363 | if (__split_bio(md, c)) |
1364 | bio_io_error(c); | |
1da177e4 | 1365 | } |
73d410c0 MB |
1366 | |
1367 | clear_bit(DMF_BLOCK_IO, &md->flags); | |
1da177e4 LT |
1368 | } |
1369 | ||
6d6f10df MB |
1370 | static void __merge_pushback_list(struct mapped_device *md) |
1371 | { | |
1372 | unsigned long flags; | |
1373 | ||
1374 | spin_lock_irqsave(&md->pushback_lock, flags); | |
1375 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
1376 | bio_list_merge_head(&md->deferred, &md->pushback); | |
1377 | bio_list_init(&md->pushback); | |
1378 | spin_unlock_irqrestore(&md->pushback_lock, flags); | |
1379 | } | |
1380 | ||
304f3f6a MB |
1381 | static void dm_wq_work(struct work_struct *work) |
1382 | { | |
1383 | struct dm_wq_req *req = container_of(work, struct dm_wq_req, work); | |
1384 | struct mapped_device *md = req->md; | |
1385 | ||
1386 | down_write(&md->io_lock); | |
1387 | switch (req->type) { | |
1388 | case DM_WQ_FLUSH_ALL: | |
1389 | __merge_pushback_list(md); | |
1390 | /* pass through */ | |
1391 | case DM_WQ_FLUSH_DEFERRED: | |
1392 | __flush_deferred_io(md); | |
1393 | break; | |
1394 | default: | |
1395 | DMERR("dm_wq_work: unrecognised work type %d", req->type); | |
1396 | BUG(); | |
1397 | } | |
1398 | up_write(&md->io_lock); | |
1399 | } | |
1400 | ||
1401 | static void dm_wq_queue(struct mapped_device *md, int type, void *context, | |
1402 | struct dm_wq_req *req) | |
1403 | { | |
1404 | req->type = type; | |
1405 | req->md = md; | |
1406 | req->context = context; | |
1407 | INIT_WORK(&req->work, dm_wq_work); | |
1408 | queue_work(md->wq, &req->work); | |
1409 | } | |
1410 | ||
1411 | static void dm_queue_flush(struct mapped_device *md, int type, void *context) | |
1412 | { | |
1413 | struct dm_wq_req req; | |
1414 | ||
1415 | dm_wq_queue(md, type, context, &req); | |
1416 | flush_workqueue(md->wq); | |
1417 | } | |
1418 | ||
1da177e4 LT |
1419 | /* |
1420 | * Swap in a new table (destroying old one). | |
1421 | */ | |
1422 | int dm_swap_table(struct mapped_device *md, struct dm_table *table) | |
1423 | { | |
93c534ae | 1424 | int r = -EINVAL; |
1da177e4 | 1425 | |
e61290a4 | 1426 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
1427 | |
1428 | /* device must be suspended */ | |
cf222b37 | 1429 | if (!dm_suspended(md)) |
93c534ae | 1430 | goto out; |
1da177e4 | 1431 | |
bfa152fa JN |
1432 | /* without bdev, the device size cannot be changed */ |
1433 | if (!md->suspended_bdev) | |
1434 | if (get_capacity(md->disk) != dm_table_get_size(table)) | |
1435 | goto out; | |
1436 | ||
1da177e4 LT |
1437 | __unbind(md); |
1438 | r = __bind(md, table); | |
1da177e4 | 1439 | |
93c534ae | 1440 | out: |
e61290a4 | 1441 | mutex_unlock(&md->suspend_lock); |
93c534ae | 1442 | return r; |
1da177e4 LT |
1443 | } |
1444 | ||
1445 | /* | |
1446 | * Functions to lock and unlock any filesystem running on the | |
1447 | * device. | |
1448 | */ | |
2ca3310e | 1449 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 1450 | { |
e39e2e95 | 1451 | int r; |
1da177e4 LT |
1452 | |
1453 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 1454 | |
e39e2e95 | 1455 | md->frozen_sb = freeze_bdev(md->suspended_bdev); |
dfbe03f6 | 1456 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 1457 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
1458 | md->frozen_sb = NULL; |
1459 | return r; | |
dfbe03f6 AK |
1460 | } |
1461 | ||
aa8d7c2f AK |
1462 | set_bit(DMF_FROZEN, &md->flags); |
1463 | ||
1da177e4 | 1464 | /* don't bdput right now, we don't want the bdev |
e39e2e95 | 1465 | * to go away while it is locked. |
1da177e4 LT |
1466 | */ |
1467 | return 0; | |
1468 | } | |
1469 | ||
2ca3310e | 1470 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 1471 | { |
aa8d7c2f AK |
1472 | if (!test_bit(DMF_FROZEN, &md->flags)) |
1473 | return; | |
1474 | ||
e39e2e95 | 1475 | thaw_bdev(md->suspended_bdev, md->frozen_sb); |
1da177e4 | 1476 | md->frozen_sb = NULL; |
aa8d7c2f | 1477 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
1478 | } |
1479 | ||
1480 | /* | |
1481 | * We need to be able to change a mapping table under a mounted | |
1482 | * filesystem. For example we might want to move some data in | |
1483 | * the background. Before the table can be swapped with | |
1484 | * dm_bind_table, dm_suspend must be called to flush any in | |
1485 | * flight bios and ensure that any further io gets deferred. | |
1486 | */ | |
a3d77d35 | 1487 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) |
1da177e4 | 1488 | { |
2ca3310e | 1489 | struct dm_table *map = NULL; |
1da177e4 | 1490 | DECLARE_WAITQUEUE(wait, current); |
46125c1c | 1491 | int r = 0; |
a3d77d35 | 1492 | int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0; |
2e93ccc1 | 1493 | int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0; |
1da177e4 | 1494 | |
e61290a4 | 1495 | mutex_lock(&md->suspend_lock); |
2ca3310e | 1496 | |
73d410c0 MB |
1497 | if (dm_suspended(md)) { |
1498 | r = -EINVAL; | |
d287483d | 1499 | goto out_unlock; |
73d410c0 | 1500 | } |
1da177e4 LT |
1501 | |
1502 | map = dm_get_table(md); | |
1da177e4 | 1503 | |
2e93ccc1 KU |
1504 | /* |
1505 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
1506 | * This flag is cleared before dm_suspend returns. | |
1507 | */ | |
1508 | if (noflush) | |
1509 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
1510 | ||
cf222b37 AK |
1511 | /* This does not get reverted if there's an error later. */ |
1512 | dm_table_presuspend_targets(map); | |
1513 | ||
bfa152fa JN |
1514 | /* bdget() can stall if the pending I/Os are not flushed */ |
1515 | if (!noflush) { | |
1516 | md->suspended_bdev = bdget_disk(md->disk, 0); | |
1517 | if (!md->suspended_bdev) { | |
1518 | DMWARN("bdget failed in dm_suspend"); | |
1519 | r = -ENOMEM; | |
1520 | goto flush_and_out; | |
1521 | } | |
e39e2e95 | 1522 | |
6d6f10df MB |
1523 | /* |
1524 | * Flush I/O to the device. noflush supersedes do_lockfs, | |
1525 | * because lock_fs() needs to flush I/Os. | |
1526 | */ | |
1527 | if (do_lockfs) { | |
1528 | r = lock_fs(md); | |
1529 | if (r) | |
1530 | goto out; | |
1531 | } | |
aa8d7c2f | 1532 | } |
1da177e4 LT |
1533 | |
1534 | /* | |
354e0071 | 1535 | * First we set the BLOCK_IO flag so no more ios will be mapped. |
1da177e4 | 1536 | */ |
2ca3310e AK |
1537 | down_write(&md->io_lock); |
1538 | set_bit(DMF_BLOCK_IO, &md->flags); | |
1da177e4 | 1539 | |
1da177e4 | 1540 | add_wait_queue(&md->wait, &wait); |
2ca3310e | 1541 | up_write(&md->io_lock); |
1da177e4 LT |
1542 | |
1543 | /* unplug */ | |
2ca3310e | 1544 | if (map) |
1da177e4 | 1545 | dm_table_unplug_all(map); |
1da177e4 LT |
1546 | |
1547 | /* | |
46125c1c | 1548 | * Wait for the already-mapped ios to complete. |
1da177e4 | 1549 | */ |
46125c1c | 1550 | r = dm_wait_for_completion(md); |
1da177e4 | 1551 | |
2ca3310e | 1552 | down_write(&md->io_lock); |
1da177e4 LT |
1553 | remove_wait_queue(&md->wait, &wait); |
1554 | ||
6d6f10df MB |
1555 | if (noflush) |
1556 | __merge_pushback_list(md); | |
94d6351e | 1557 | up_write(&md->io_lock); |
2e93ccc1 | 1558 | |
1da177e4 | 1559 | /* were we interrupted ? */ |
46125c1c | 1560 | if (r < 0) { |
304f3f6a | 1561 | dm_queue_flush(md, DM_WQ_FLUSH_DEFERRED, NULL); |
73d410c0 | 1562 | |
2ca3310e | 1563 | unlock_fs(md); |
2e93ccc1 | 1564 | goto out; /* pushback list is already flushed, so skip flush */ |
2ca3310e | 1565 | } |
1da177e4 | 1566 | |
cf222b37 | 1567 | dm_table_postsuspend_targets(map); |
1da177e4 | 1568 | |
2ca3310e | 1569 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 1570 | |
2e93ccc1 | 1571 | flush_and_out: |
304f3f6a | 1572 | if (r && noflush) |
2e93ccc1 KU |
1573 | /* |
1574 | * Because there may be already I/Os in the pushback list, | |
1575 | * flush them before return. | |
1576 | */ | |
304f3f6a | 1577 | dm_queue_flush(md, DM_WQ_FLUSH_ALL, NULL); |
2e93ccc1 | 1578 | |
2ca3310e | 1579 | out: |
e39e2e95 AK |
1580 | if (r && md->suspended_bdev) { |
1581 | bdput(md->suspended_bdev); | |
1582 | md->suspended_bdev = NULL; | |
1583 | } | |
1584 | ||
2ca3310e | 1585 | dm_table_put(map); |
d287483d AK |
1586 | |
1587 | out_unlock: | |
e61290a4 | 1588 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 1589 | return r; |
1da177e4 LT |
1590 | } |
1591 | ||
1592 | int dm_resume(struct mapped_device *md) | |
1593 | { | |
cf222b37 | 1594 | int r = -EINVAL; |
cf222b37 | 1595 | struct dm_table *map = NULL; |
1da177e4 | 1596 | |
e61290a4 | 1597 | mutex_lock(&md->suspend_lock); |
2ca3310e | 1598 | if (!dm_suspended(md)) |
cf222b37 | 1599 | goto out; |
cf222b37 AK |
1600 | |
1601 | map = dm_get_table(md); | |
2ca3310e | 1602 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 1603 | goto out; |
1da177e4 | 1604 | |
8757b776 MB |
1605 | r = dm_table_resume_targets(map); |
1606 | if (r) | |
1607 | goto out; | |
2ca3310e | 1608 | |
304f3f6a | 1609 | dm_queue_flush(md, DM_WQ_FLUSH_DEFERRED, NULL); |
2ca3310e AK |
1610 | |
1611 | unlock_fs(md); | |
1612 | ||
bfa152fa JN |
1613 | if (md->suspended_bdev) { |
1614 | bdput(md->suspended_bdev); | |
1615 | md->suspended_bdev = NULL; | |
1616 | } | |
e39e2e95 | 1617 | |
2ca3310e AK |
1618 | clear_bit(DMF_SUSPENDED, &md->flags); |
1619 | ||
1da177e4 | 1620 | dm_table_unplug_all(map); |
1da177e4 | 1621 | |
69267a30 | 1622 | dm_kobject_uevent(md); |
8560ed6f | 1623 | |
cf222b37 | 1624 | r = 0; |
2ca3310e | 1625 | |
cf222b37 AK |
1626 | out: |
1627 | dm_table_put(map); | |
e61290a4 | 1628 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 1629 | |
cf222b37 | 1630 | return r; |
1da177e4 LT |
1631 | } |
1632 | ||
1633 | /*----------------------------------------------------------------- | |
1634 | * Event notification. | |
1635 | *---------------------------------------------------------------*/ | |
69267a30 AK |
1636 | void dm_kobject_uevent(struct mapped_device *md) |
1637 | { | |
edfaa7c3 | 1638 | kobject_uevent(&md->disk->dev.kobj, KOBJ_CHANGE); |
69267a30 AK |
1639 | } |
1640 | ||
7a8c3d3b MA |
1641 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
1642 | { | |
1643 | return atomic_add_return(1, &md->uevent_seq); | |
1644 | } | |
1645 | ||
1da177e4 LT |
1646 | uint32_t dm_get_event_nr(struct mapped_device *md) |
1647 | { | |
1648 | return atomic_read(&md->event_nr); | |
1649 | } | |
1650 | ||
1651 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
1652 | { | |
1653 | return wait_event_interruptible(md->eventq, | |
1654 | (event_nr != atomic_read(&md->event_nr))); | |
1655 | } | |
1656 | ||
7a8c3d3b MA |
1657 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
1658 | { | |
1659 | unsigned long flags; | |
1660 | ||
1661 | spin_lock_irqsave(&md->uevent_lock, flags); | |
1662 | list_add(elist, &md->uevent_list); | |
1663 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
1664 | } | |
1665 | ||
1da177e4 LT |
1666 | /* |
1667 | * The gendisk is only valid as long as you have a reference | |
1668 | * count on 'md'. | |
1669 | */ | |
1670 | struct gendisk *dm_disk(struct mapped_device *md) | |
1671 | { | |
1672 | return md->disk; | |
1673 | } | |
1674 | ||
1675 | int dm_suspended(struct mapped_device *md) | |
1676 | { | |
1677 | return test_bit(DMF_SUSPENDED, &md->flags); | |
1678 | } | |
1679 | ||
2e93ccc1 KU |
1680 | int dm_noflush_suspending(struct dm_target *ti) |
1681 | { | |
1682 | struct mapped_device *md = dm_table_get_md(ti->table); | |
1683 | int r = __noflush_suspending(md); | |
1684 | ||
1685 | dm_put(md); | |
1686 | ||
1687 | return r; | |
1688 | } | |
1689 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
1690 | ||
1da177e4 LT |
1691 | static struct block_device_operations dm_blk_dops = { |
1692 | .open = dm_blk_open, | |
1693 | .release = dm_blk_close, | |
aa129a22 | 1694 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 1695 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
1696 | .owner = THIS_MODULE |
1697 | }; | |
1698 | ||
1699 | EXPORT_SYMBOL(dm_get_mapinfo); | |
1700 | ||
1701 | /* | |
1702 | * module hooks | |
1703 | */ | |
1704 | module_init(dm_init); | |
1705 | module_exit(dm_exit); | |
1706 | ||
1707 | module_param(major, uint, 0); | |
1708 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
1709 | MODULE_DESCRIPTION(DM_NAME " driver"); | |
1710 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
1711 | MODULE_LICENSE("GPL"); |