Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. | |
784aae73 | 3 | * Copyright (C) 2004-2008 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> |
5f3ea37c | 24 | #include <trace/block.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 | 34 | /* |
8fbf26ad | 35 | * For bio-based dm. |
1da177e4 LT |
36 | * One of these is allocated per bio. |
37 | */ | |
38 | struct dm_io { | |
39 | struct mapped_device *md; | |
40 | int error; | |
1da177e4 | 41 | atomic_t io_count; |
6ae2fa67 | 42 | struct bio *bio; |
3eaf840e | 43 | unsigned long start_time; |
1da177e4 LT |
44 | }; |
45 | ||
46 | /* | |
8fbf26ad | 47 | * For bio-based dm. |
1da177e4 LT |
48 | * One of these is allocated per target within a bio. Hopefully |
49 | * this will be simplified out one day. | |
50 | */ | |
028867ac | 51 | struct dm_target_io { |
1da177e4 LT |
52 | struct dm_io *io; |
53 | struct dm_target *ti; | |
54 | union map_info info; | |
55 | }; | |
56 | ||
0bfc2455 IM |
57 | DEFINE_TRACE(block_bio_complete); |
58 | ||
8fbf26ad KU |
59 | /* |
60 | * For request-based dm. | |
61 | * One of these is allocated per request. | |
62 | */ | |
63 | struct dm_rq_target_io { | |
64 | struct mapped_device *md; | |
65 | struct dm_target *ti; | |
66 | struct request *orig, clone; | |
67 | int error; | |
68 | union map_info info; | |
69 | }; | |
70 | ||
71 | /* | |
72 | * For request-based dm. | |
73 | * One of these is allocated per bio. | |
74 | */ | |
75 | struct dm_rq_clone_bio_info { | |
76 | struct bio *orig; | |
77 | struct request *rq; | |
78 | }; | |
79 | ||
1da177e4 LT |
80 | union map_info *dm_get_mapinfo(struct bio *bio) |
81 | { | |
17b2f66f | 82 | if (bio && bio->bi_private) |
028867ac | 83 | return &((struct dm_target_io *)bio->bi_private)->info; |
17b2f66f | 84 | return NULL; |
1da177e4 LT |
85 | } |
86 | ||
ba61fdd1 JM |
87 | #define MINOR_ALLOCED ((void *)-1) |
88 | ||
1da177e4 LT |
89 | /* |
90 | * Bits for the md->flags field. | |
91 | */ | |
92 | #define DMF_BLOCK_IO 0 | |
93 | #define DMF_SUSPENDED 1 | |
aa8d7c2f | 94 | #define DMF_FROZEN 2 |
fba9f90e | 95 | #define DMF_FREEING 3 |
5c6bd75d | 96 | #define DMF_DELETING 4 |
2e93ccc1 | 97 | #define DMF_NOFLUSH_SUSPENDING 5 |
1da177e4 | 98 | |
304f3f6a MB |
99 | /* |
100 | * Work processed by per-device workqueue. | |
101 | */ | |
102 | struct dm_wq_req { | |
103 | enum { | |
304f3f6a MB |
104 | DM_WQ_FLUSH_DEFERRED, |
105 | } type; | |
106 | struct work_struct work; | |
107 | struct mapped_device *md; | |
108 | void *context; | |
109 | }; | |
110 | ||
1da177e4 | 111 | struct mapped_device { |
2ca3310e | 112 | struct rw_semaphore io_lock; |
e61290a4 | 113 | struct mutex suspend_lock; |
2e93ccc1 | 114 | spinlock_t pushback_lock; |
1da177e4 LT |
115 | rwlock_t map_lock; |
116 | atomic_t holders; | |
5c6bd75d | 117 | atomic_t open_count; |
1da177e4 LT |
118 | |
119 | unsigned long flags; | |
120 | ||
165125e1 | 121 | struct request_queue *queue; |
1da177e4 | 122 | struct gendisk *disk; |
7e51f257 | 123 | char name[16]; |
1da177e4 LT |
124 | |
125 | void *interface_ptr; | |
126 | ||
127 | /* | |
128 | * A list of ios that arrived while we were suspended. | |
129 | */ | |
130 | atomic_t pending; | |
131 | wait_queue_head_t wait; | |
74859364 | 132 | struct bio_list deferred; |
2e93ccc1 | 133 | struct bio_list pushback; |
1da177e4 | 134 | |
304f3f6a MB |
135 | /* |
136 | * Processing queue (flush/barriers) | |
137 | */ | |
138 | struct workqueue_struct *wq; | |
139 | ||
1da177e4 LT |
140 | /* |
141 | * The current mapping. | |
142 | */ | |
143 | struct dm_table *map; | |
144 | ||
145 | /* | |
146 | * io objects are allocated from here. | |
147 | */ | |
148 | mempool_t *io_pool; | |
149 | mempool_t *tio_pool; | |
150 | ||
9faf400f SB |
151 | struct bio_set *bs; |
152 | ||
1da177e4 LT |
153 | /* |
154 | * Event handling. | |
155 | */ | |
156 | atomic_t event_nr; | |
157 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
158 | atomic_t uevent_seq; |
159 | struct list_head uevent_list; | |
160 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
161 | |
162 | /* | |
163 | * freeze/thaw support require holding onto a super block | |
164 | */ | |
165 | struct super_block *frozen_sb; | |
e39e2e95 | 166 | struct block_device *suspended_bdev; |
3ac51e74 DW |
167 | |
168 | /* forced geometry settings */ | |
169 | struct hd_geometry geometry; | |
784aae73 MB |
170 | |
171 | /* sysfs handle */ | |
172 | struct kobject kobj; | |
1da177e4 LT |
173 | }; |
174 | ||
175 | #define MIN_IOS 256 | |
e18b890b CL |
176 | static struct kmem_cache *_io_cache; |
177 | static struct kmem_cache *_tio_cache; | |
8fbf26ad KU |
178 | static struct kmem_cache *_rq_tio_cache; |
179 | static struct kmem_cache *_rq_bio_info_cache; | |
1da177e4 | 180 | |
1da177e4 LT |
181 | static int __init local_init(void) |
182 | { | |
51157b4a | 183 | int r = -ENOMEM; |
1da177e4 | 184 | |
1da177e4 | 185 | /* allocate a slab for the dm_ios */ |
028867ac | 186 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 | 187 | if (!_io_cache) |
51157b4a | 188 | return r; |
1da177e4 LT |
189 | |
190 | /* allocate a slab for the target ios */ | |
028867ac | 191 | _tio_cache = KMEM_CACHE(dm_target_io, 0); |
51157b4a KU |
192 | if (!_tio_cache) |
193 | goto out_free_io_cache; | |
1da177e4 | 194 | |
8fbf26ad KU |
195 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
196 | if (!_rq_tio_cache) | |
197 | goto out_free_tio_cache; | |
198 | ||
199 | _rq_bio_info_cache = KMEM_CACHE(dm_rq_clone_bio_info, 0); | |
200 | if (!_rq_bio_info_cache) | |
201 | goto out_free_rq_tio_cache; | |
202 | ||
51e5b2bd | 203 | r = dm_uevent_init(); |
51157b4a | 204 | if (r) |
8fbf26ad | 205 | goto out_free_rq_bio_info_cache; |
51e5b2bd | 206 | |
1da177e4 LT |
207 | _major = major; |
208 | r = register_blkdev(_major, _name); | |
51157b4a KU |
209 | if (r < 0) |
210 | goto out_uevent_exit; | |
1da177e4 LT |
211 | |
212 | if (!_major) | |
213 | _major = r; | |
214 | ||
215 | return 0; | |
51157b4a KU |
216 | |
217 | out_uevent_exit: | |
218 | dm_uevent_exit(); | |
8fbf26ad KU |
219 | out_free_rq_bio_info_cache: |
220 | kmem_cache_destroy(_rq_bio_info_cache); | |
221 | out_free_rq_tio_cache: | |
222 | kmem_cache_destroy(_rq_tio_cache); | |
51157b4a KU |
223 | out_free_tio_cache: |
224 | kmem_cache_destroy(_tio_cache); | |
225 | out_free_io_cache: | |
226 | kmem_cache_destroy(_io_cache); | |
227 | ||
228 | return r; | |
1da177e4 LT |
229 | } |
230 | ||
231 | static void local_exit(void) | |
232 | { | |
8fbf26ad KU |
233 | kmem_cache_destroy(_rq_bio_info_cache); |
234 | kmem_cache_destroy(_rq_tio_cache); | |
1da177e4 LT |
235 | kmem_cache_destroy(_tio_cache); |
236 | kmem_cache_destroy(_io_cache); | |
00d59405 | 237 | unregister_blkdev(_major, _name); |
51e5b2bd | 238 | dm_uevent_exit(); |
1da177e4 LT |
239 | |
240 | _major = 0; | |
241 | ||
242 | DMINFO("cleaned up"); | |
243 | } | |
244 | ||
b9249e55 | 245 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
246 | local_init, |
247 | dm_target_init, | |
248 | dm_linear_init, | |
249 | dm_stripe_init, | |
945fa4d2 | 250 | dm_kcopyd_init, |
1da177e4 LT |
251 | dm_interface_init, |
252 | }; | |
253 | ||
b9249e55 | 254 | static void (*_exits[])(void) = { |
1da177e4 LT |
255 | local_exit, |
256 | dm_target_exit, | |
257 | dm_linear_exit, | |
258 | dm_stripe_exit, | |
945fa4d2 | 259 | dm_kcopyd_exit, |
1da177e4 LT |
260 | dm_interface_exit, |
261 | }; | |
262 | ||
263 | static int __init dm_init(void) | |
264 | { | |
265 | const int count = ARRAY_SIZE(_inits); | |
266 | ||
267 | int r, i; | |
268 | ||
269 | for (i = 0; i < count; i++) { | |
270 | r = _inits[i](); | |
271 | if (r) | |
272 | goto bad; | |
273 | } | |
274 | ||
275 | return 0; | |
276 | ||
277 | bad: | |
278 | while (i--) | |
279 | _exits[i](); | |
280 | ||
281 | return r; | |
282 | } | |
283 | ||
284 | static void __exit dm_exit(void) | |
285 | { | |
286 | int i = ARRAY_SIZE(_exits); | |
287 | ||
288 | while (i--) | |
289 | _exits[i](); | |
290 | } | |
291 | ||
292 | /* | |
293 | * Block device functions | |
294 | */ | |
fe5f9f2c | 295 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
296 | { |
297 | struct mapped_device *md; | |
298 | ||
fba9f90e JM |
299 | spin_lock(&_minor_lock); |
300 | ||
fe5f9f2c | 301 | md = bdev->bd_disk->private_data; |
fba9f90e JM |
302 | if (!md) |
303 | goto out; | |
304 | ||
5c6bd75d AK |
305 | if (test_bit(DMF_FREEING, &md->flags) || |
306 | test_bit(DMF_DELETING, &md->flags)) { | |
fba9f90e JM |
307 | md = NULL; |
308 | goto out; | |
309 | } | |
310 | ||
1da177e4 | 311 | dm_get(md); |
5c6bd75d | 312 | atomic_inc(&md->open_count); |
fba9f90e JM |
313 | |
314 | out: | |
315 | spin_unlock(&_minor_lock); | |
316 | ||
317 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
318 | } |
319 | ||
fe5f9f2c | 320 | static int dm_blk_close(struct gendisk *disk, fmode_t mode) |
1da177e4 | 321 | { |
fe5f9f2c | 322 | struct mapped_device *md = disk->private_data; |
5c6bd75d | 323 | atomic_dec(&md->open_count); |
1da177e4 LT |
324 | dm_put(md); |
325 | return 0; | |
326 | } | |
327 | ||
5c6bd75d AK |
328 | int dm_open_count(struct mapped_device *md) |
329 | { | |
330 | return atomic_read(&md->open_count); | |
331 | } | |
332 | ||
333 | /* | |
334 | * Guarantees nothing is using the device before it's deleted. | |
335 | */ | |
336 | int dm_lock_for_deletion(struct mapped_device *md) | |
337 | { | |
338 | int r = 0; | |
339 | ||
340 | spin_lock(&_minor_lock); | |
341 | ||
342 | if (dm_open_count(md)) | |
343 | r = -EBUSY; | |
344 | else | |
345 | set_bit(DMF_DELETING, &md->flags); | |
346 | ||
347 | spin_unlock(&_minor_lock); | |
348 | ||
349 | return r; | |
350 | } | |
351 | ||
3ac51e74 DW |
352 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
353 | { | |
354 | struct mapped_device *md = bdev->bd_disk->private_data; | |
355 | ||
356 | return dm_get_geometry(md, geo); | |
357 | } | |
358 | ||
fe5f9f2c | 359 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
aa129a22 MB |
360 | unsigned int cmd, unsigned long arg) |
361 | { | |
fe5f9f2c AV |
362 | struct mapped_device *md = bdev->bd_disk->private_data; |
363 | struct dm_table *map = dm_get_table(md); | |
aa129a22 MB |
364 | struct dm_target *tgt; |
365 | int r = -ENOTTY; | |
366 | ||
aa129a22 MB |
367 | if (!map || !dm_table_get_size(map)) |
368 | goto out; | |
369 | ||
370 | /* We only support devices that have a single target */ | |
371 | if (dm_table_get_num_targets(map) != 1) | |
372 | goto out; | |
373 | ||
374 | tgt = dm_table_get_target(map, 0); | |
375 | ||
376 | if (dm_suspended(md)) { | |
377 | r = -EAGAIN; | |
378 | goto out; | |
379 | } | |
380 | ||
381 | if (tgt->type->ioctl) | |
647b3d00 | 382 | r = tgt->type->ioctl(tgt, cmd, arg); |
aa129a22 MB |
383 | |
384 | out: | |
385 | dm_table_put(map); | |
386 | ||
aa129a22 MB |
387 | return r; |
388 | } | |
389 | ||
028867ac | 390 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
391 | { |
392 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
393 | } | |
394 | ||
028867ac | 395 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
396 | { |
397 | mempool_free(io, md->io_pool); | |
398 | } | |
399 | ||
028867ac | 400 | static struct dm_target_io *alloc_tio(struct mapped_device *md) |
1da177e4 LT |
401 | { |
402 | return mempool_alloc(md->tio_pool, GFP_NOIO); | |
403 | } | |
404 | ||
028867ac | 405 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 LT |
406 | { |
407 | mempool_free(tio, md->tio_pool); | |
408 | } | |
409 | ||
3eaf840e JNN |
410 | static void start_io_acct(struct dm_io *io) |
411 | { | |
412 | struct mapped_device *md = io->md; | |
c9959059 | 413 | int cpu; |
3eaf840e JNN |
414 | |
415 | io->start_time = jiffies; | |
416 | ||
074a7aca TH |
417 | cpu = part_stat_lock(); |
418 | part_round_stats(cpu, &dm_disk(md)->part0); | |
419 | part_stat_unlock(); | |
420 | dm_disk(md)->part0.in_flight = atomic_inc_return(&md->pending); | |
3eaf840e JNN |
421 | } |
422 | ||
d221d2e7 | 423 | static void end_io_acct(struct dm_io *io) |
3eaf840e JNN |
424 | { |
425 | struct mapped_device *md = io->md; | |
426 | struct bio *bio = io->bio; | |
427 | unsigned long duration = jiffies - io->start_time; | |
c9959059 | 428 | int pending, cpu; |
3eaf840e JNN |
429 | int rw = bio_data_dir(bio); |
430 | ||
074a7aca TH |
431 | cpu = part_stat_lock(); |
432 | part_round_stats(cpu, &dm_disk(md)->part0); | |
433 | part_stat_add(cpu, &dm_disk(md)->part0, ticks[rw], duration); | |
434 | part_stat_unlock(); | |
3eaf840e | 435 | |
074a7aca TH |
436 | dm_disk(md)->part0.in_flight = pending = |
437 | atomic_dec_return(&md->pending); | |
3eaf840e | 438 | |
d221d2e7 MP |
439 | /* nudge anyone waiting on suspend queue */ |
440 | if (!pending) | |
441 | wake_up(&md->wait); | |
3eaf840e JNN |
442 | } |
443 | ||
1da177e4 LT |
444 | /* |
445 | * Add the bio to the list of deferred io. | |
446 | */ | |
447 | static int queue_io(struct mapped_device *md, struct bio *bio) | |
448 | { | |
2ca3310e | 449 | down_write(&md->io_lock); |
1da177e4 LT |
450 | |
451 | if (!test_bit(DMF_BLOCK_IO, &md->flags)) { | |
2ca3310e | 452 | up_write(&md->io_lock); |
1da177e4 LT |
453 | return 1; |
454 | } | |
455 | ||
456 | bio_list_add(&md->deferred, bio); | |
457 | ||
2ca3310e | 458 | up_write(&md->io_lock); |
1da177e4 LT |
459 | return 0; /* deferred successfully */ |
460 | } | |
461 | ||
462 | /* | |
463 | * Everyone (including functions in this file), should use this | |
464 | * function to access the md->map field, and make sure they call | |
465 | * dm_table_put() when finished. | |
466 | */ | |
467 | struct dm_table *dm_get_table(struct mapped_device *md) | |
468 | { | |
469 | struct dm_table *t; | |
470 | ||
471 | read_lock(&md->map_lock); | |
472 | t = md->map; | |
473 | if (t) | |
474 | dm_table_get(t); | |
475 | read_unlock(&md->map_lock); | |
476 | ||
477 | return t; | |
478 | } | |
479 | ||
3ac51e74 DW |
480 | /* |
481 | * Get the geometry associated with a dm device | |
482 | */ | |
483 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
484 | { | |
485 | *geo = md->geometry; | |
486 | ||
487 | return 0; | |
488 | } | |
489 | ||
490 | /* | |
491 | * Set the geometry of a device. | |
492 | */ | |
493 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
494 | { | |
495 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
496 | ||
497 | if (geo->start > sz) { | |
498 | DMWARN("Start sector is beyond the geometry limits."); | |
499 | return -EINVAL; | |
500 | } | |
501 | ||
502 | md->geometry = *geo; | |
503 | ||
504 | return 0; | |
505 | } | |
506 | ||
1da177e4 LT |
507 | /*----------------------------------------------------------------- |
508 | * CRUD START: | |
509 | * A more elegant soln is in the works that uses the queue | |
510 | * merge fn, unfortunately there are a couple of changes to | |
511 | * the block layer that I want to make for this. So in the | |
512 | * interests of getting something for people to use I give | |
513 | * you this clearly demarcated crap. | |
514 | *---------------------------------------------------------------*/ | |
515 | ||
2e93ccc1 KU |
516 | static int __noflush_suspending(struct mapped_device *md) |
517 | { | |
518 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
519 | } | |
520 | ||
1da177e4 LT |
521 | /* |
522 | * Decrements the number of outstanding ios that a bio has been | |
523 | * cloned into, completing the original io if necc. | |
524 | */ | |
858119e1 | 525 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 526 | { |
2e93ccc1 | 527 | unsigned long flags; |
b35f8caa MB |
528 | int io_error; |
529 | struct bio *bio; | |
530 | struct mapped_device *md = io->md; | |
2e93ccc1 KU |
531 | |
532 | /* Push-back supersedes any I/O errors */ | |
b35f8caa | 533 | if (error && !(io->error > 0 && __noflush_suspending(md))) |
1da177e4 LT |
534 | io->error = error; |
535 | ||
536 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
537 | if (io->error == DM_ENDIO_REQUEUE) { |
538 | /* | |
539 | * Target requested pushing back the I/O. | |
540 | * This must be handled before the sleeper on | |
541 | * suspend queue merges the pushback list. | |
542 | */ | |
b35f8caa MB |
543 | spin_lock_irqsave(&md->pushback_lock, flags); |
544 | if (__noflush_suspending(md)) | |
545 | bio_list_add(&md->pushback, io->bio); | |
2e93ccc1 KU |
546 | else |
547 | /* noflush suspend was interrupted. */ | |
548 | io->error = -EIO; | |
b35f8caa | 549 | spin_unlock_irqrestore(&md->pushback_lock, flags); |
2e93ccc1 KU |
550 | } |
551 | ||
d221d2e7 | 552 | end_io_acct(io); |
1da177e4 | 553 | |
b35f8caa MB |
554 | io_error = io->error; |
555 | bio = io->bio; | |
2e93ccc1 | 556 | |
b35f8caa MB |
557 | free_io(md, io); |
558 | ||
559 | if (io_error != DM_ENDIO_REQUEUE) { | |
560 | trace_block_bio_complete(md->queue, bio); | |
2056a782 | 561 | |
b35f8caa MB |
562 | bio_endio(bio, io_error); |
563 | } | |
1da177e4 LT |
564 | } |
565 | } | |
566 | ||
6712ecf8 | 567 | static void clone_endio(struct bio *bio, int error) |
1da177e4 LT |
568 | { |
569 | int r = 0; | |
028867ac | 570 | struct dm_target_io *tio = bio->bi_private; |
b35f8caa | 571 | struct dm_io *io = tio->io; |
9faf400f | 572 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
573 | dm_endio_fn endio = tio->ti->type->end_io; |
574 | ||
1da177e4 LT |
575 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
576 | error = -EIO; | |
577 | ||
578 | if (endio) { | |
579 | r = endio(tio->ti, bio, error, &tio->info); | |
2e93ccc1 KU |
580 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
581 | /* | |
582 | * error and requeue request are handled | |
583 | * in dec_pending(). | |
584 | */ | |
1da177e4 | 585 | error = r; |
45cbcd79 KU |
586 | else if (r == DM_ENDIO_INCOMPLETE) |
587 | /* The target will handle the io */ | |
6712ecf8 | 588 | return; |
45cbcd79 KU |
589 | else if (r) { |
590 | DMWARN("unimplemented target endio return value: %d", r); | |
591 | BUG(); | |
592 | } | |
1da177e4 LT |
593 | } |
594 | ||
9faf400f SB |
595 | /* |
596 | * Store md for cleanup instead of tio which is about to get freed. | |
597 | */ | |
598 | bio->bi_private = md->bs; | |
599 | ||
9faf400f | 600 | free_tio(md, tio); |
b35f8caa MB |
601 | bio_put(bio); |
602 | dec_pending(io, error); | |
1da177e4 LT |
603 | } |
604 | ||
605 | static sector_t max_io_len(struct mapped_device *md, | |
606 | sector_t sector, struct dm_target *ti) | |
607 | { | |
608 | sector_t offset = sector - ti->begin; | |
609 | sector_t len = ti->len - offset; | |
610 | ||
611 | /* | |
612 | * Does the target need to split even further ? | |
613 | */ | |
614 | if (ti->split_io) { | |
615 | sector_t boundary; | |
616 | boundary = ((offset + ti->split_io) & ~(ti->split_io - 1)) | |
617 | - offset; | |
618 | if (len > boundary) | |
619 | len = boundary; | |
620 | } | |
621 | ||
622 | return len; | |
623 | } | |
624 | ||
625 | static void __map_bio(struct dm_target *ti, struct bio *clone, | |
028867ac | 626 | struct dm_target_io *tio) |
1da177e4 LT |
627 | { |
628 | int r; | |
2056a782 | 629 | sector_t sector; |
9faf400f | 630 | struct mapped_device *md; |
1da177e4 LT |
631 | |
632 | /* | |
633 | * Sanity checks. | |
634 | */ | |
635 | BUG_ON(!clone->bi_size); | |
636 | ||
637 | clone->bi_end_io = clone_endio; | |
638 | clone->bi_private = tio; | |
639 | ||
640 | /* | |
641 | * Map the clone. If r == 0 we don't need to do | |
642 | * anything, the target has assumed ownership of | |
643 | * this io. | |
644 | */ | |
645 | atomic_inc(&tio->io->io_count); | |
2056a782 | 646 | sector = clone->bi_sector; |
1da177e4 | 647 | r = ti->type->map(ti, clone, &tio->info); |
45cbcd79 | 648 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 649 | /* the bio has been remapped so dispatch it */ |
2056a782 | 650 | |
5f3ea37c | 651 | trace_block_remap(bdev_get_queue(clone->bi_bdev), clone, |
c7149d6b AB |
652 | tio->io->bio->bi_bdev->bd_dev, |
653 | clone->bi_sector, sector); | |
2056a782 | 654 | |
1da177e4 | 655 | generic_make_request(clone); |
2e93ccc1 KU |
656 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
657 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
658 | md = tio->io->md; |
659 | dec_pending(tio->io, r); | |
660 | /* | |
661 | * Store bio_set for cleanup. | |
662 | */ | |
663 | clone->bi_private = md->bs; | |
1da177e4 | 664 | bio_put(clone); |
9faf400f | 665 | free_tio(md, tio); |
45cbcd79 KU |
666 | } else if (r) { |
667 | DMWARN("unimplemented target map return value: %d", r); | |
668 | BUG(); | |
1da177e4 LT |
669 | } |
670 | } | |
671 | ||
672 | struct clone_info { | |
673 | struct mapped_device *md; | |
674 | struct dm_table *map; | |
675 | struct bio *bio; | |
676 | struct dm_io *io; | |
677 | sector_t sector; | |
678 | sector_t sector_count; | |
679 | unsigned short idx; | |
680 | }; | |
681 | ||
3676347a PO |
682 | static void dm_bio_destructor(struct bio *bio) |
683 | { | |
9faf400f SB |
684 | struct bio_set *bs = bio->bi_private; |
685 | ||
686 | bio_free(bio, bs); | |
3676347a PO |
687 | } |
688 | ||
1da177e4 LT |
689 | /* |
690 | * Creates a little bio that is just does part of a bvec. | |
691 | */ | |
692 | static struct bio *split_bvec(struct bio *bio, sector_t sector, | |
693 | unsigned short idx, unsigned int offset, | |
9faf400f | 694 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
695 | { |
696 | struct bio *clone; | |
697 | struct bio_vec *bv = bio->bi_io_vec + idx; | |
698 | ||
9faf400f | 699 | clone = bio_alloc_bioset(GFP_NOIO, 1, bs); |
3676347a | 700 | clone->bi_destructor = dm_bio_destructor; |
1da177e4 LT |
701 | *clone->bi_io_vec = *bv; |
702 | ||
703 | clone->bi_sector = sector; | |
704 | clone->bi_bdev = bio->bi_bdev; | |
705 | clone->bi_rw = bio->bi_rw; | |
706 | clone->bi_vcnt = 1; | |
707 | clone->bi_size = to_bytes(len); | |
708 | clone->bi_io_vec->bv_offset = offset; | |
709 | clone->bi_io_vec->bv_len = clone->bi_size; | |
f3e1d26e | 710 | clone->bi_flags |= 1 << BIO_CLONED; |
1da177e4 LT |
711 | |
712 | return clone; | |
713 | } | |
714 | ||
715 | /* | |
716 | * Creates a bio that consists of range of complete bvecs. | |
717 | */ | |
718 | static struct bio *clone_bio(struct bio *bio, sector_t sector, | |
719 | unsigned short idx, unsigned short bv_count, | |
9faf400f | 720 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
721 | { |
722 | struct bio *clone; | |
723 | ||
9faf400f SB |
724 | clone = bio_alloc_bioset(GFP_NOIO, bio->bi_max_vecs, bs); |
725 | __bio_clone(clone, bio); | |
726 | clone->bi_destructor = dm_bio_destructor; | |
1da177e4 LT |
727 | clone->bi_sector = sector; |
728 | clone->bi_idx = idx; | |
729 | clone->bi_vcnt = idx + bv_count; | |
730 | clone->bi_size = to_bytes(len); | |
731 | clone->bi_flags &= ~(1 << BIO_SEG_VALID); | |
732 | ||
733 | return clone; | |
734 | } | |
735 | ||
512875bd | 736 | static int __clone_and_map(struct clone_info *ci) |
1da177e4 LT |
737 | { |
738 | struct bio *clone, *bio = ci->bio; | |
512875bd JN |
739 | struct dm_target *ti; |
740 | sector_t len = 0, max; | |
028867ac | 741 | struct dm_target_io *tio; |
1da177e4 | 742 | |
512875bd JN |
743 | ti = dm_table_find_target(ci->map, ci->sector); |
744 | if (!dm_target_is_valid(ti)) | |
745 | return -EIO; | |
746 | ||
747 | max = max_io_len(ci->md, ci->sector, ti); | |
748 | ||
1da177e4 LT |
749 | /* |
750 | * Allocate a target io object. | |
751 | */ | |
752 | tio = alloc_tio(ci->md); | |
753 | tio->io = ci->io; | |
754 | tio->ti = ti; | |
755 | memset(&tio->info, 0, sizeof(tio->info)); | |
756 | ||
757 | if (ci->sector_count <= max) { | |
758 | /* | |
759 | * Optimise for the simple case where we can do all of | |
760 | * the remaining io with a single clone. | |
761 | */ | |
762 | clone = clone_bio(bio, ci->sector, ci->idx, | |
9faf400f SB |
763 | bio->bi_vcnt - ci->idx, ci->sector_count, |
764 | ci->md->bs); | |
1da177e4 LT |
765 | __map_bio(ti, clone, tio); |
766 | ci->sector_count = 0; | |
767 | ||
768 | } else if (to_sector(bio->bi_io_vec[ci->idx].bv_len) <= max) { | |
769 | /* | |
770 | * There are some bvecs that don't span targets. | |
771 | * Do as many of these as possible. | |
772 | */ | |
773 | int i; | |
774 | sector_t remaining = max; | |
775 | sector_t bv_len; | |
776 | ||
777 | for (i = ci->idx; remaining && (i < bio->bi_vcnt); i++) { | |
778 | bv_len = to_sector(bio->bi_io_vec[i].bv_len); | |
779 | ||
780 | if (bv_len > remaining) | |
781 | break; | |
782 | ||
783 | remaining -= bv_len; | |
784 | len += bv_len; | |
785 | } | |
786 | ||
9faf400f SB |
787 | clone = clone_bio(bio, ci->sector, ci->idx, i - ci->idx, len, |
788 | ci->md->bs); | |
1da177e4 LT |
789 | __map_bio(ti, clone, tio); |
790 | ||
791 | ci->sector += len; | |
792 | ci->sector_count -= len; | |
793 | ci->idx = i; | |
794 | ||
795 | } else { | |
796 | /* | |
d2044a94 | 797 | * Handle a bvec that must be split between two or more targets. |
1da177e4 LT |
798 | */ |
799 | struct bio_vec *bv = bio->bi_io_vec + ci->idx; | |
d2044a94 AK |
800 | sector_t remaining = to_sector(bv->bv_len); |
801 | unsigned int offset = 0; | |
1da177e4 | 802 | |
d2044a94 AK |
803 | do { |
804 | if (offset) { | |
805 | ti = dm_table_find_target(ci->map, ci->sector); | |
512875bd JN |
806 | if (!dm_target_is_valid(ti)) |
807 | return -EIO; | |
808 | ||
d2044a94 | 809 | max = max_io_len(ci->md, ci->sector, ti); |
1da177e4 | 810 | |
d2044a94 AK |
811 | tio = alloc_tio(ci->md); |
812 | tio->io = ci->io; | |
813 | tio->ti = ti; | |
814 | memset(&tio->info, 0, sizeof(tio->info)); | |
815 | } | |
816 | ||
817 | len = min(remaining, max); | |
818 | ||
819 | clone = split_bvec(bio, ci->sector, ci->idx, | |
9faf400f SB |
820 | bv->bv_offset + offset, len, |
821 | ci->md->bs); | |
d2044a94 AK |
822 | |
823 | __map_bio(ti, clone, tio); | |
824 | ||
825 | ci->sector += len; | |
826 | ci->sector_count -= len; | |
827 | offset += to_bytes(len); | |
828 | } while (remaining -= len); | |
1da177e4 | 829 | |
1da177e4 LT |
830 | ci->idx++; |
831 | } | |
512875bd JN |
832 | |
833 | return 0; | |
1da177e4 LT |
834 | } |
835 | ||
836 | /* | |
837 | * Split the bio into several clones. | |
838 | */ | |
9e4e5f87 | 839 | static int __split_bio(struct mapped_device *md, struct bio *bio) |
1da177e4 LT |
840 | { |
841 | struct clone_info ci; | |
512875bd | 842 | int error = 0; |
1da177e4 LT |
843 | |
844 | ci.map = dm_get_table(md); | |
9e4e5f87 MB |
845 | if (unlikely(!ci.map)) |
846 | return -EIO; | |
ab4c1424 AK |
847 | if (unlikely(bio_barrier(bio) && !dm_table_barrier_ok(ci.map))) { |
848 | dm_table_put(ci.map); | |
849 | bio_endio(bio, -EOPNOTSUPP); | |
850 | return 0; | |
851 | } | |
1da177e4 LT |
852 | ci.md = md; |
853 | ci.bio = bio; | |
854 | ci.io = alloc_io(md); | |
855 | ci.io->error = 0; | |
856 | atomic_set(&ci.io->io_count, 1); | |
857 | ci.io->bio = bio; | |
858 | ci.io->md = md; | |
859 | ci.sector = bio->bi_sector; | |
860 | ci.sector_count = bio_sectors(bio); | |
861 | ci.idx = bio->bi_idx; | |
862 | ||
3eaf840e | 863 | start_io_acct(ci.io); |
512875bd JN |
864 | while (ci.sector_count && !error) |
865 | error = __clone_and_map(&ci); | |
1da177e4 LT |
866 | |
867 | /* drop the extra reference count */ | |
512875bd | 868 | dec_pending(ci.io, error); |
1da177e4 | 869 | dm_table_put(ci.map); |
9e4e5f87 MB |
870 | |
871 | return 0; | |
1da177e4 LT |
872 | } |
873 | /*----------------------------------------------------------------- | |
874 | * CRUD END | |
875 | *---------------------------------------------------------------*/ | |
876 | ||
f6fccb12 MB |
877 | static int dm_merge_bvec(struct request_queue *q, |
878 | struct bvec_merge_data *bvm, | |
879 | struct bio_vec *biovec) | |
880 | { | |
881 | struct mapped_device *md = q->queuedata; | |
882 | struct dm_table *map = dm_get_table(md); | |
883 | struct dm_target *ti; | |
884 | sector_t max_sectors; | |
5037108a | 885 | int max_size = 0; |
f6fccb12 MB |
886 | |
887 | if (unlikely(!map)) | |
5037108a | 888 | goto out; |
f6fccb12 MB |
889 | |
890 | ti = dm_table_find_target(map, bvm->bi_sector); | |
b01cd5ac MP |
891 | if (!dm_target_is_valid(ti)) |
892 | goto out_table; | |
f6fccb12 MB |
893 | |
894 | /* | |
895 | * Find maximum amount of I/O that won't need splitting | |
896 | */ | |
897 | max_sectors = min(max_io_len(md, bvm->bi_sector, ti), | |
898 | (sector_t) BIO_MAX_SECTORS); | |
899 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; | |
900 | if (max_size < 0) | |
901 | max_size = 0; | |
902 | ||
903 | /* | |
904 | * merge_bvec_fn() returns number of bytes | |
905 | * it can accept at this offset | |
906 | * max is precomputed maximal io size | |
907 | */ | |
908 | if (max_size && ti->type->merge) | |
909 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
910 | ||
b01cd5ac | 911 | out_table: |
5037108a MP |
912 | dm_table_put(map); |
913 | ||
914 | out: | |
f6fccb12 MB |
915 | /* |
916 | * Always allow an entire first page | |
917 | */ | |
918 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
919 | max_size = biovec->bv_len; | |
920 | ||
f6fccb12 MB |
921 | return max_size; |
922 | } | |
923 | ||
1da177e4 LT |
924 | /* |
925 | * The request function that just remaps the bio built up by | |
926 | * dm_merge_bvec. | |
927 | */ | |
165125e1 | 928 | static int dm_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 929 | { |
9e4e5f87 | 930 | int r = -EIO; |
12f03a49 | 931 | int rw = bio_data_dir(bio); |
1da177e4 | 932 | struct mapped_device *md = q->queuedata; |
c9959059 | 933 | int cpu; |
1da177e4 | 934 | |
2ca3310e | 935 | down_read(&md->io_lock); |
1da177e4 | 936 | |
074a7aca TH |
937 | cpu = part_stat_lock(); |
938 | part_stat_inc(cpu, &dm_disk(md)->part0, ios[rw]); | |
939 | part_stat_add(cpu, &dm_disk(md)->part0, sectors[rw], bio_sectors(bio)); | |
940 | part_stat_unlock(); | |
12f03a49 | 941 | |
1da177e4 LT |
942 | /* |
943 | * If we're suspended we have to queue | |
944 | * this io for later. | |
945 | */ | |
946 | while (test_bit(DMF_BLOCK_IO, &md->flags)) { | |
2ca3310e | 947 | up_read(&md->io_lock); |
1da177e4 | 948 | |
9e4e5f87 MB |
949 | if (bio_rw(bio) != READA) |
950 | r = queue_io(md, bio); | |
1da177e4 | 951 | |
9e4e5f87 MB |
952 | if (r <= 0) |
953 | goto out_req; | |
1da177e4 LT |
954 | |
955 | /* | |
956 | * We're in a while loop, because someone could suspend | |
957 | * before we get to the following read lock. | |
958 | */ | |
2ca3310e | 959 | down_read(&md->io_lock); |
1da177e4 LT |
960 | } |
961 | ||
9e4e5f87 | 962 | r = __split_bio(md, bio); |
2ca3310e | 963 | up_read(&md->io_lock); |
9e4e5f87 MB |
964 | |
965 | out_req: | |
966 | if (r < 0) | |
967 | bio_io_error(bio); | |
968 | ||
1da177e4 LT |
969 | return 0; |
970 | } | |
971 | ||
165125e1 | 972 | static void dm_unplug_all(struct request_queue *q) |
1da177e4 LT |
973 | { |
974 | struct mapped_device *md = q->queuedata; | |
975 | struct dm_table *map = dm_get_table(md); | |
976 | ||
977 | if (map) { | |
978 | dm_table_unplug_all(map); | |
979 | dm_table_put(map); | |
980 | } | |
981 | } | |
982 | ||
983 | static int dm_any_congested(void *congested_data, int bdi_bits) | |
984 | { | |
8a57dfc6 CS |
985 | int r = bdi_bits; |
986 | struct mapped_device *md = congested_data; | |
987 | struct dm_table *map; | |
1da177e4 | 988 | |
8a57dfc6 CS |
989 | if (!test_bit(DMF_BLOCK_IO, &md->flags)) { |
990 | map = dm_get_table(md); | |
991 | if (map) { | |
992 | r = dm_table_any_congested(map, bdi_bits); | |
993 | dm_table_put(map); | |
994 | } | |
995 | } | |
996 | ||
1da177e4 LT |
997 | return r; |
998 | } | |
999 | ||
1000 | /*----------------------------------------------------------------- | |
1001 | * An IDR is used to keep track of allocated minor numbers. | |
1002 | *---------------------------------------------------------------*/ | |
1da177e4 LT |
1003 | static DEFINE_IDR(_minor_idr); |
1004 | ||
2b06cfff | 1005 | static void free_minor(int minor) |
1da177e4 | 1006 | { |
f32c10b0 | 1007 | spin_lock(&_minor_lock); |
1da177e4 | 1008 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 1009 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1010 | } |
1011 | ||
1012 | /* | |
1013 | * See if the device with a specific minor # is free. | |
1014 | */ | |
cf13ab8e | 1015 | static int specific_minor(int minor) |
1da177e4 LT |
1016 | { |
1017 | int r, m; | |
1018 | ||
1019 | if (minor >= (1 << MINORBITS)) | |
1020 | return -EINVAL; | |
1021 | ||
62f75c2f JM |
1022 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
1023 | if (!r) | |
1024 | return -ENOMEM; | |
1025 | ||
f32c10b0 | 1026 | spin_lock(&_minor_lock); |
1da177e4 LT |
1027 | |
1028 | if (idr_find(&_minor_idr, minor)) { | |
1029 | r = -EBUSY; | |
1030 | goto out; | |
1031 | } | |
1032 | ||
ba61fdd1 | 1033 | r = idr_get_new_above(&_minor_idr, MINOR_ALLOCED, minor, &m); |
62f75c2f | 1034 | if (r) |
1da177e4 | 1035 | goto out; |
1da177e4 LT |
1036 | |
1037 | if (m != minor) { | |
1038 | idr_remove(&_minor_idr, m); | |
1039 | r = -EBUSY; | |
1040 | goto out; | |
1041 | } | |
1042 | ||
1043 | out: | |
f32c10b0 | 1044 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1045 | return r; |
1046 | } | |
1047 | ||
cf13ab8e | 1048 | static int next_free_minor(int *minor) |
1da177e4 | 1049 | { |
2b06cfff | 1050 | int r, m; |
1da177e4 | 1051 | |
1da177e4 | 1052 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
62f75c2f JM |
1053 | if (!r) |
1054 | return -ENOMEM; | |
1055 | ||
f32c10b0 | 1056 | spin_lock(&_minor_lock); |
1da177e4 | 1057 | |
ba61fdd1 | 1058 | r = idr_get_new(&_minor_idr, MINOR_ALLOCED, &m); |
cf13ab8e | 1059 | if (r) |
1da177e4 | 1060 | goto out; |
1da177e4 LT |
1061 | |
1062 | if (m >= (1 << MINORBITS)) { | |
1063 | idr_remove(&_minor_idr, m); | |
1064 | r = -ENOSPC; | |
1065 | goto out; | |
1066 | } | |
1067 | ||
1068 | *minor = m; | |
1069 | ||
1070 | out: | |
f32c10b0 | 1071 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1072 | return r; |
1073 | } | |
1074 | ||
1075 | static struct block_device_operations dm_blk_dops; | |
1076 | ||
1077 | /* | |
1078 | * Allocate and initialise a blank device with a given minor. | |
1079 | */ | |
2b06cfff | 1080 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
1081 | { |
1082 | int r; | |
cf13ab8e | 1083 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 1084 | void *old_md; |
1da177e4 LT |
1085 | |
1086 | if (!md) { | |
1087 | DMWARN("unable to allocate device, out of memory."); | |
1088 | return NULL; | |
1089 | } | |
1090 | ||
10da4f79 | 1091 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 1092 | goto bad_module_get; |
10da4f79 | 1093 | |
1da177e4 | 1094 | /* get a minor number for the dev */ |
2b06cfff | 1095 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 1096 | r = next_free_minor(&minor); |
2b06cfff | 1097 | else |
cf13ab8e | 1098 | r = specific_minor(minor); |
1da177e4 | 1099 | if (r < 0) |
6ed7ade8 | 1100 | goto bad_minor; |
1da177e4 | 1101 | |
2ca3310e | 1102 | init_rwsem(&md->io_lock); |
e61290a4 | 1103 | mutex_init(&md->suspend_lock); |
2e93ccc1 | 1104 | spin_lock_init(&md->pushback_lock); |
1da177e4 LT |
1105 | rwlock_init(&md->map_lock); |
1106 | atomic_set(&md->holders, 1); | |
5c6bd75d | 1107 | atomic_set(&md->open_count, 0); |
1da177e4 | 1108 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
1109 | atomic_set(&md->uevent_seq, 0); |
1110 | INIT_LIST_HEAD(&md->uevent_list); | |
1111 | spin_lock_init(&md->uevent_lock); | |
1da177e4 LT |
1112 | |
1113 | md->queue = blk_alloc_queue(GFP_KERNEL); | |
1114 | if (!md->queue) | |
6ed7ade8 | 1115 | goto bad_queue; |
1da177e4 LT |
1116 | |
1117 | md->queue->queuedata = md; | |
1118 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
1119 | md->queue->backing_dev_info.congested_data = md; | |
1120 | blk_queue_make_request(md->queue, dm_request); | |
daef265f | 1121 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); |
1da177e4 | 1122 | md->queue->unplug_fn = dm_unplug_all; |
f6fccb12 | 1123 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); |
1da177e4 | 1124 | |
93d2341c | 1125 | md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache); |
74859364 | 1126 | if (!md->io_pool) |
6ed7ade8 | 1127 | goto bad_io_pool; |
1da177e4 | 1128 | |
93d2341c | 1129 | md->tio_pool = mempool_create_slab_pool(MIN_IOS, _tio_cache); |
1da177e4 | 1130 | if (!md->tio_pool) |
6ed7ade8 | 1131 | goto bad_tio_pool; |
1da177e4 | 1132 | |
bb799ca0 | 1133 | md->bs = bioset_create(16, 0); |
9faf400f SB |
1134 | if (!md->bs) |
1135 | goto bad_no_bioset; | |
1136 | ||
1da177e4 LT |
1137 | md->disk = alloc_disk(1); |
1138 | if (!md->disk) | |
6ed7ade8 | 1139 | goto bad_disk; |
1da177e4 | 1140 | |
f0b04115 JM |
1141 | atomic_set(&md->pending, 0); |
1142 | init_waitqueue_head(&md->wait); | |
1143 | init_waitqueue_head(&md->eventq); | |
1144 | ||
1da177e4 LT |
1145 | md->disk->major = _major; |
1146 | md->disk->first_minor = minor; | |
1147 | md->disk->fops = &dm_blk_dops; | |
1148 | md->disk->queue = md->queue; | |
1149 | md->disk->private_data = md; | |
1150 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
1151 | add_disk(md->disk); | |
7e51f257 | 1152 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 1153 | |
304f3f6a MB |
1154 | md->wq = create_singlethread_workqueue("kdmflush"); |
1155 | if (!md->wq) | |
1156 | goto bad_thread; | |
1157 | ||
ba61fdd1 | 1158 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 1159 | spin_lock(&_minor_lock); |
ba61fdd1 | 1160 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 1161 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
1162 | |
1163 | BUG_ON(old_md != MINOR_ALLOCED); | |
1164 | ||
1da177e4 LT |
1165 | return md; |
1166 | ||
304f3f6a MB |
1167 | bad_thread: |
1168 | put_disk(md->disk); | |
6ed7ade8 | 1169 | bad_disk: |
9faf400f | 1170 | bioset_free(md->bs); |
6ed7ade8 | 1171 | bad_no_bioset: |
1da177e4 | 1172 | mempool_destroy(md->tio_pool); |
6ed7ade8 | 1173 | bad_tio_pool: |
1da177e4 | 1174 | mempool_destroy(md->io_pool); |
6ed7ade8 | 1175 | bad_io_pool: |
1312f40e | 1176 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 1177 | bad_queue: |
1da177e4 | 1178 | free_minor(minor); |
6ed7ade8 | 1179 | bad_minor: |
10da4f79 | 1180 | module_put(THIS_MODULE); |
6ed7ade8 | 1181 | bad_module_get: |
1da177e4 LT |
1182 | kfree(md); |
1183 | return NULL; | |
1184 | } | |
1185 | ||
ae9da83f JN |
1186 | static void unlock_fs(struct mapped_device *md); |
1187 | ||
1da177e4 LT |
1188 | static void free_dev(struct mapped_device *md) |
1189 | { | |
f331c029 | 1190 | int minor = MINOR(disk_devt(md->disk)); |
63d94e48 | 1191 | |
d9dde59b | 1192 | if (md->suspended_bdev) { |
ae9da83f | 1193 | unlock_fs(md); |
d9dde59b JN |
1194 | bdput(md->suspended_bdev); |
1195 | } | |
304f3f6a | 1196 | destroy_workqueue(md->wq); |
1da177e4 LT |
1197 | mempool_destroy(md->tio_pool); |
1198 | mempool_destroy(md->io_pool); | |
9faf400f | 1199 | bioset_free(md->bs); |
1da177e4 | 1200 | del_gendisk(md->disk); |
63d94e48 | 1201 | free_minor(minor); |
fba9f90e JM |
1202 | |
1203 | spin_lock(&_minor_lock); | |
1204 | md->disk->private_data = NULL; | |
1205 | spin_unlock(&_minor_lock); | |
1206 | ||
1da177e4 | 1207 | put_disk(md->disk); |
1312f40e | 1208 | blk_cleanup_queue(md->queue); |
10da4f79 | 1209 | module_put(THIS_MODULE); |
1da177e4 LT |
1210 | kfree(md); |
1211 | } | |
1212 | ||
1213 | /* | |
1214 | * Bind a table to the device. | |
1215 | */ | |
1216 | static void event_callback(void *context) | |
1217 | { | |
7a8c3d3b MA |
1218 | unsigned long flags; |
1219 | LIST_HEAD(uevents); | |
1da177e4 LT |
1220 | struct mapped_device *md = (struct mapped_device *) context; |
1221 | ||
7a8c3d3b MA |
1222 | spin_lock_irqsave(&md->uevent_lock, flags); |
1223 | list_splice_init(&md->uevent_list, &uevents); | |
1224 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
1225 | ||
ed9e1982 | 1226 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
7a8c3d3b | 1227 | |
1da177e4 LT |
1228 | atomic_inc(&md->event_nr); |
1229 | wake_up(&md->eventq); | |
1230 | } | |
1231 | ||
4e90188b | 1232 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 1233 | { |
4e90188b | 1234 | set_capacity(md->disk, size); |
1da177e4 | 1235 | |
1b1dcc1b | 1236 | mutex_lock(&md->suspended_bdev->bd_inode->i_mutex); |
e39e2e95 | 1237 | i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
1b1dcc1b | 1238 | mutex_unlock(&md->suspended_bdev->bd_inode->i_mutex); |
1da177e4 LT |
1239 | } |
1240 | ||
1241 | static int __bind(struct mapped_device *md, struct dm_table *t) | |
1242 | { | |
165125e1 | 1243 | struct request_queue *q = md->queue; |
1da177e4 LT |
1244 | sector_t size; |
1245 | ||
1246 | size = dm_table_get_size(t); | |
3ac51e74 DW |
1247 | |
1248 | /* | |
1249 | * Wipe any geometry if the size of the table changed. | |
1250 | */ | |
1251 | if (size != get_capacity(md->disk)) | |
1252 | memset(&md->geometry, 0, sizeof(md->geometry)); | |
1253 | ||
bfa152fa JN |
1254 | if (md->suspended_bdev) |
1255 | __set_size(md, size); | |
d5816876 MP |
1256 | |
1257 | if (!size) { | |
1258 | dm_table_destroy(t); | |
1da177e4 | 1259 | return 0; |
d5816876 | 1260 | } |
1da177e4 | 1261 | |
2ca3310e AK |
1262 | dm_table_event_callback(t, event_callback, md); |
1263 | ||
1da177e4 LT |
1264 | write_lock(&md->map_lock); |
1265 | md->map = t; | |
2ca3310e | 1266 | dm_table_set_restrictions(t, q); |
1da177e4 LT |
1267 | write_unlock(&md->map_lock); |
1268 | ||
1da177e4 LT |
1269 | return 0; |
1270 | } | |
1271 | ||
1272 | static void __unbind(struct mapped_device *md) | |
1273 | { | |
1274 | struct dm_table *map = md->map; | |
1275 | ||
1276 | if (!map) | |
1277 | return; | |
1278 | ||
1279 | dm_table_event_callback(map, NULL, NULL); | |
1280 | write_lock(&md->map_lock); | |
1281 | md->map = NULL; | |
1282 | write_unlock(&md->map_lock); | |
d5816876 | 1283 | dm_table_destroy(map); |
1da177e4 LT |
1284 | } |
1285 | ||
1286 | /* | |
1287 | * Constructor for a new device. | |
1288 | */ | |
2b06cfff | 1289 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
1290 | { |
1291 | struct mapped_device *md; | |
1292 | ||
2b06cfff | 1293 | md = alloc_dev(minor); |
1da177e4 LT |
1294 | if (!md) |
1295 | return -ENXIO; | |
1296 | ||
784aae73 MB |
1297 | dm_sysfs_init(md); |
1298 | ||
1da177e4 LT |
1299 | *result = md; |
1300 | return 0; | |
1301 | } | |
1302 | ||
637842cf | 1303 | static struct mapped_device *dm_find_md(dev_t dev) |
1da177e4 LT |
1304 | { |
1305 | struct mapped_device *md; | |
1da177e4 LT |
1306 | unsigned minor = MINOR(dev); |
1307 | ||
1308 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
1309 | return NULL; | |
1310 | ||
f32c10b0 | 1311 | spin_lock(&_minor_lock); |
1da177e4 LT |
1312 | |
1313 | md = idr_find(&_minor_idr, minor); | |
fba9f90e | 1314 | if (md && (md == MINOR_ALLOCED || |
f331c029 | 1315 | (MINOR(disk_devt(dm_disk(md))) != minor) || |
17b2f66f | 1316 | test_bit(DMF_FREEING, &md->flags))) { |
637842cf | 1317 | md = NULL; |
fba9f90e JM |
1318 | goto out; |
1319 | } | |
1da177e4 | 1320 | |
fba9f90e | 1321 | out: |
f32c10b0 | 1322 | spin_unlock(&_minor_lock); |
1da177e4 | 1323 | |
637842cf DT |
1324 | return md; |
1325 | } | |
1326 | ||
d229a958 DT |
1327 | struct mapped_device *dm_get_md(dev_t dev) |
1328 | { | |
1329 | struct mapped_device *md = dm_find_md(dev); | |
1330 | ||
1331 | if (md) | |
1332 | dm_get(md); | |
1333 | ||
1334 | return md; | |
1335 | } | |
1336 | ||
9ade92a9 | 1337 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 1338 | { |
9ade92a9 | 1339 | return md->interface_ptr; |
1da177e4 LT |
1340 | } |
1341 | ||
1342 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
1343 | { | |
1344 | md->interface_ptr = ptr; | |
1345 | } | |
1346 | ||
1347 | void dm_get(struct mapped_device *md) | |
1348 | { | |
1349 | atomic_inc(&md->holders); | |
1350 | } | |
1351 | ||
72d94861 AK |
1352 | const char *dm_device_name(struct mapped_device *md) |
1353 | { | |
1354 | return md->name; | |
1355 | } | |
1356 | EXPORT_SYMBOL_GPL(dm_device_name); | |
1357 | ||
1da177e4 LT |
1358 | void dm_put(struct mapped_device *md) |
1359 | { | |
1134e5ae | 1360 | struct dm_table *map; |
1da177e4 | 1361 | |
fba9f90e JM |
1362 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
1363 | ||
f32c10b0 | 1364 | if (atomic_dec_and_lock(&md->holders, &_minor_lock)) { |
1134e5ae | 1365 | map = dm_get_table(md); |
f331c029 TH |
1366 | idr_replace(&_minor_idr, MINOR_ALLOCED, |
1367 | MINOR(disk_devt(dm_disk(md)))); | |
fba9f90e | 1368 | set_bit(DMF_FREEING, &md->flags); |
f32c10b0 | 1369 | spin_unlock(&_minor_lock); |
cf222b37 | 1370 | if (!dm_suspended(md)) { |
1da177e4 LT |
1371 | dm_table_presuspend_targets(map); |
1372 | dm_table_postsuspend_targets(map); | |
1373 | } | |
784aae73 | 1374 | dm_sysfs_exit(md); |
1134e5ae | 1375 | dm_table_put(map); |
a1b51e98 | 1376 | __unbind(md); |
1da177e4 LT |
1377 | free_dev(md); |
1378 | } | |
1da177e4 | 1379 | } |
79eb885c | 1380 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 1381 | |
46125c1c MB |
1382 | static int dm_wait_for_completion(struct mapped_device *md) |
1383 | { | |
1384 | int r = 0; | |
1385 | ||
1386 | while (1) { | |
1387 | set_current_state(TASK_INTERRUPTIBLE); | |
1388 | ||
1389 | smp_mb(); | |
1390 | if (!atomic_read(&md->pending)) | |
1391 | break; | |
1392 | ||
1393 | if (signal_pending(current)) { | |
1394 | r = -EINTR; | |
1395 | break; | |
1396 | } | |
1397 | ||
1398 | io_schedule(); | |
1399 | } | |
1400 | set_current_state(TASK_RUNNING); | |
1401 | ||
1402 | return r; | |
1403 | } | |
1404 | ||
1da177e4 LT |
1405 | /* |
1406 | * Process the deferred bios | |
1407 | */ | |
6d6f10df | 1408 | static void __flush_deferred_io(struct mapped_device *md) |
1da177e4 | 1409 | { |
6d6f10df | 1410 | struct bio *c; |
1da177e4 | 1411 | |
6d6f10df | 1412 | while ((c = bio_list_pop(&md->deferred))) { |
9e4e5f87 MB |
1413 | if (__split_bio(md, c)) |
1414 | bio_io_error(c); | |
1da177e4 | 1415 | } |
73d410c0 MB |
1416 | |
1417 | clear_bit(DMF_BLOCK_IO, &md->flags); | |
1da177e4 LT |
1418 | } |
1419 | ||
6d6f10df MB |
1420 | static void __merge_pushback_list(struct mapped_device *md) |
1421 | { | |
1422 | unsigned long flags; | |
1423 | ||
1424 | spin_lock_irqsave(&md->pushback_lock, flags); | |
1425 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
1426 | bio_list_merge_head(&md->deferred, &md->pushback); | |
1427 | bio_list_init(&md->pushback); | |
1428 | spin_unlock_irqrestore(&md->pushback_lock, flags); | |
1429 | } | |
1430 | ||
304f3f6a MB |
1431 | static void dm_wq_work(struct work_struct *work) |
1432 | { | |
1433 | struct dm_wq_req *req = container_of(work, struct dm_wq_req, work); | |
1434 | struct mapped_device *md = req->md; | |
1435 | ||
1436 | down_write(&md->io_lock); | |
1437 | switch (req->type) { | |
304f3f6a MB |
1438 | case DM_WQ_FLUSH_DEFERRED: |
1439 | __flush_deferred_io(md); | |
1440 | break; | |
1441 | default: | |
1442 | DMERR("dm_wq_work: unrecognised work type %d", req->type); | |
1443 | BUG(); | |
1444 | } | |
1445 | up_write(&md->io_lock); | |
1446 | } | |
1447 | ||
1448 | static void dm_wq_queue(struct mapped_device *md, int type, void *context, | |
1449 | struct dm_wq_req *req) | |
1450 | { | |
1451 | req->type = type; | |
1452 | req->md = md; | |
1453 | req->context = context; | |
1454 | INIT_WORK(&req->work, dm_wq_work); | |
1455 | queue_work(md->wq, &req->work); | |
1456 | } | |
1457 | ||
1458 | static void dm_queue_flush(struct mapped_device *md, int type, void *context) | |
1459 | { | |
1460 | struct dm_wq_req req; | |
1461 | ||
1462 | dm_wq_queue(md, type, context, &req); | |
1463 | flush_workqueue(md->wq); | |
1464 | } | |
1465 | ||
1da177e4 LT |
1466 | /* |
1467 | * Swap in a new table (destroying old one). | |
1468 | */ | |
1469 | int dm_swap_table(struct mapped_device *md, struct dm_table *table) | |
1470 | { | |
93c534ae | 1471 | int r = -EINVAL; |
1da177e4 | 1472 | |
e61290a4 | 1473 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
1474 | |
1475 | /* device must be suspended */ | |
cf222b37 | 1476 | if (!dm_suspended(md)) |
93c534ae | 1477 | goto out; |
1da177e4 | 1478 | |
bfa152fa JN |
1479 | /* without bdev, the device size cannot be changed */ |
1480 | if (!md->suspended_bdev) | |
1481 | if (get_capacity(md->disk) != dm_table_get_size(table)) | |
1482 | goto out; | |
1483 | ||
1da177e4 LT |
1484 | __unbind(md); |
1485 | r = __bind(md, table); | |
1da177e4 | 1486 | |
93c534ae | 1487 | out: |
e61290a4 | 1488 | mutex_unlock(&md->suspend_lock); |
93c534ae | 1489 | return r; |
1da177e4 LT |
1490 | } |
1491 | ||
1492 | /* | |
1493 | * Functions to lock and unlock any filesystem running on the | |
1494 | * device. | |
1495 | */ | |
2ca3310e | 1496 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 1497 | { |
e39e2e95 | 1498 | int r; |
1da177e4 LT |
1499 | |
1500 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 1501 | |
e39e2e95 | 1502 | md->frozen_sb = freeze_bdev(md->suspended_bdev); |
dfbe03f6 | 1503 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 1504 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
1505 | md->frozen_sb = NULL; |
1506 | return r; | |
dfbe03f6 AK |
1507 | } |
1508 | ||
aa8d7c2f AK |
1509 | set_bit(DMF_FROZEN, &md->flags); |
1510 | ||
1da177e4 | 1511 | /* don't bdput right now, we don't want the bdev |
e39e2e95 | 1512 | * to go away while it is locked. |
1da177e4 LT |
1513 | */ |
1514 | return 0; | |
1515 | } | |
1516 | ||
2ca3310e | 1517 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 1518 | { |
aa8d7c2f AK |
1519 | if (!test_bit(DMF_FROZEN, &md->flags)) |
1520 | return; | |
1521 | ||
e39e2e95 | 1522 | thaw_bdev(md->suspended_bdev, md->frozen_sb); |
1da177e4 | 1523 | md->frozen_sb = NULL; |
aa8d7c2f | 1524 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
1525 | } |
1526 | ||
1527 | /* | |
1528 | * We need to be able to change a mapping table under a mounted | |
1529 | * filesystem. For example we might want to move some data in | |
1530 | * the background. Before the table can be swapped with | |
1531 | * dm_bind_table, dm_suspend must be called to flush any in | |
1532 | * flight bios and ensure that any further io gets deferred. | |
1533 | */ | |
a3d77d35 | 1534 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) |
1da177e4 | 1535 | { |
2ca3310e | 1536 | struct dm_table *map = NULL; |
1da177e4 | 1537 | DECLARE_WAITQUEUE(wait, current); |
46125c1c | 1538 | int r = 0; |
a3d77d35 | 1539 | int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0; |
2e93ccc1 | 1540 | int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0; |
1da177e4 | 1541 | |
e61290a4 | 1542 | mutex_lock(&md->suspend_lock); |
2ca3310e | 1543 | |
73d410c0 MB |
1544 | if (dm_suspended(md)) { |
1545 | r = -EINVAL; | |
d287483d | 1546 | goto out_unlock; |
73d410c0 | 1547 | } |
1da177e4 LT |
1548 | |
1549 | map = dm_get_table(md); | |
1da177e4 | 1550 | |
2e93ccc1 KU |
1551 | /* |
1552 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
1553 | * This flag is cleared before dm_suspend returns. | |
1554 | */ | |
1555 | if (noflush) | |
1556 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
1557 | ||
cf222b37 AK |
1558 | /* This does not get reverted if there's an error later. */ |
1559 | dm_table_presuspend_targets(map); | |
1560 | ||
bfa152fa JN |
1561 | /* bdget() can stall if the pending I/Os are not flushed */ |
1562 | if (!noflush) { | |
1563 | md->suspended_bdev = bdget_disk(md->disk, 0); | |
1564 | if (!md->suspended_bdev) { | |
1565 | DMWARN("bdget failed in dm_suspend"); | |
1566 | r = -ENOMEM; | |
f431d966 | 1567 | goto out; |
bfa152fa | 1568 | } |
e39e2e95 | 1569 | |
6d6f10df MB |
1570 | /* |
1571 | * Flush I/O to the device. noflush supersedes do_lockfs, | |
1572 | * because lock_fs() needs to flush I/Os. | |
1573 | */ | |
1574 | if (do_lockfs) { | |
1575 | r = lock_fs(md); | |
1576 | if (r) | |
1577 | goto out; | |
1578 | } | |
aa8d7c2f | 1579 | } |
1da177e4 LT |
1580 | |
1581 | /* | |
354e0071 | 1582 | * First we set the BLOCK_IO flag so no more ios will be mapped. |
1da177e4 | 1583 | */ |
2ca3310e AK |
1584 | down_write(&md->io_lock); |
1585 | set_bit(DMF_BLOCK_IO, &md->flags); | |
1da177e4 | 1586 | |
1da177e4 | 1587 | add_wait_queue(&md->wait, &wait); |
2ca3310e | 1588 | up_write(&md->io_lock); |
1da177e4 LT |
1589 | |
1590 | /* unplug */ | |
2ca3310e | 1591 | if (map) |
1da177e4 | 1592 | dm_table_unplug_all(map); |
1da177e4 LT |
1593 | |
1594 | /* | |
46125c1c | 1595 | * Wait for the already-mapped ios to complete. |
1da177e4 | 1596 | */ |
46125c1c | 1597 | r = dm_wait_for_completion(md); |
1da177e4 | 1598 | |
2ca3310e | 1599 | down_write(&md->io_lock); |
1da177e4 LT |
1600 | remove_wait_queue(&md->wait, &wait); |
1601 | ||
6d6f10df MB |
1602 | if (noflush) |
1603 | __merge_pushback_list(md); | |
94d6351e | 1604 | up_write(&md->io_lock); |
2e93ccc1 | 1605 | |
1da177e4 | 1606 | /* were we interrupted ? */ |
46125c1c | 1607 | if (r < 0) { |
304f3f6a | 1608 | dm_queue_flush(md, DM_WQ_FLUSH_DEFERRED, NULL); |
73d410c0 | 1609 | |
2ca3310e | 1610 | unlock_fs(md); |
2e93ccc1 | 1611 | goto out; /* pushback list is already flushed, so skip flush */ |
2ca3310e | 1612 | } |
1da177e4 | 1613 | |
cf222b37 | 1614 | dm_table_postsuspend_targets(map); |
1da177e4 | 1615 | |
2ca3310e | 1616 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 1617 | |
2ca3310e | 1618 | out: |
e39e2e95 AK |
1619 | if (r && md->suspended_bdev) { |
1620 | bdput(md->suspended_bdev); | |
1621 | md->suspended_bdev = NULL; | |
1622 | } | |
1623 | ||
2ca3310e | 1624 | dm_table_put(map); |
d287483d AK |
1625 | |
1626 | out_unlock: | |
e61290a4 | 1627 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 1628 | return r; |
1da177e4 LT |
1629 | } |
1630 | ||
1631 | int dm_resume(struct mapped_device *md) | |
1632 | { | |
cf222b37 | 1633 | int r = -EINVAL; |
cf222b37 | 1634 | struct dm_table *map = NULL; |
1da177e4 | 1635 | |
e61290a4 | 1636 | mutex_lock(&md->suspend_lock); |
2ca3310e | 1637 | if (!dm_suspended(md)) |
cf222b37 | 1638 | goto out; |
cf222b37 AK |
1639 | |
1640 | map = dm_get_table(md); | |
2ca3310e | 1641 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 1642 | goto out; |
1da177e4 | 1643 | |
8757b776 MB |
1644 | r = dm_table_resume_targets(map); |
1645 | if (r) | |
1646 | goto out; | |
2ca3310e | 1647 | |
304f3f6a | 1648 | dm_queue_flush(md, DM_WQ_FLUSH_DEFERRED, NULL); |
2ca3310e AK |
1649 | |
1650 | unlock_fs(md); | |
1651 | ||
bfa152fa JN |
1652 | if (md->suspended_bdev) { |
1653 | bdput(md->suspended_bdev); | |
1654 | md->suspended_bdev = NULL; | |
1655 | } | |
e39e2e95 | 1656 | |
2ca3310e AK |
1657 | clear_bit(DMF_SUSPENDED, &md->flags); |
1658 | ||
1da177e4 | 1659 | dm_table_unplug_all(map); |
1da177e4 | 1660 | |
69267a30 | 1661 | dm_kobject_uevent(md); |
8560ed6f | 1662 | |
cf222b37 | 1663 | r = 0; |
2ca3310e | 1664 | |
cf222b37 AK |
1665 | out: |
1666 | dm_table_put(map); | |
e61290a4 | 1667 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 1668 | |
cf222b37 | 1669 | return r; |
1da177e4 LT |
1670 | } |
1671 | ||
1672 | /*----------------------------------------------------------------- | |
1673 | * Event notification. | |
1674 | *---------------------------------------------------------------*/ | |
69267a30 AK |
1675 | void dm_kobject_uevent(struct mapped_device *md) |
1676 | { | |
ed9e1982 | 1677 | kobject_uevent(&disk_to_dev(md->disk)->kobj, KOBJ_CHANGE); |
69267a30 AK |
1678 | } |
1679 | ||
7a8c3d3b MA |
1680 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
1681 | { | |
1682 | return atomic_add_return(1, &md->uevent_seq); | |
1683 | } | |
1684 | ||
1da177e4 LT |
1685 | uint32_t dm_get_event_nr(struct mapped_device *md) |
1686 | { | |
1687 | return atomic_read(&md->event_nr); | |
1688 | } | |
1689 | ||
1690 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
1691 | { | |
1692 | return wait_event_interruptible(md->eventq, | |
1693 | (event_nr != atomic_read(&md->event_nr))); | |
1694 | } | |
1695 | ||
7a8c3d3b MA |
1696 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
1697 | { | |
1698 | unsigned long flags; | |
1699 | ||
1700 | spin_lock_irqsave(&md->uevent_lock, flags); | |
1701 | list_add(elist, &md->uevent_list); | |
1702 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
1703 | } | |
1704 | ||
1da177e4 LT |
1705 | /* |
1706 | * The gendisk is only valid as long as you have a reference | |
1707 | * count on 'md'. | |
1708 | */ | |
1709 | struct gendisk *dm_disk(struct mapped_device *md) | |
1710 | { | |
1711 | return md->disk; | |
1712 | } | |
1713 | ||
784aae73 MB |
1714 | struct kobject *dm_kobject(struct mapped_device *md) |
1715 | { | |
1716 | return &md->kobj; | |
1717 | } | |
1718 | ||
1719 | /* | |
1720 | * struct mapped_device should not be exported outside of dm.c | |
1721 | * so use this check to verify that kobj is part of md structure | |
1722 | */ | |
1723 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) | |
1724 | { | |
1725 | struct mapped_device *md; | |
1726 | ||
1727 | md = container_of(kobj, struct mapped_device, kobj); | |
1728 | if (&md->kobj != kobj) | |
1729 | return NULL; | |
1730 | ||
1731 | dm_get(md); | |
1732 | return md; | |
1733 | } | |
1734 | ||
1da177e4 LT |
1735 | int dm_suspended(struct mapped_device *md) |
1736 | { | |
1737 | return test_bit(DMF_SUSPENDED, &md->flags); | |
1738 | } | |
1739 | ||
2e93ccc1 KU |
1740 | int dm_noflush_suspending(struct dm_target *ti) |
1741 | { | |
1742 | struct mapped_device *md = dm_table_get_md(ti->table); | |
1743 | int r = __noflush_suspending(md); | |
1744 | ||
1745 | dm_put(md); | |
1746 | ||
1747 | return r; | |
1748 | } | |
1749 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
1750 | ||
1da177e4 LT |
1751 | static struct block_device_operations dm_blk_dops = { |
1752 | .open = dm_blk_open, | |
1753 | .release = dm_blk_close, | |
aa129a22 | 1754 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 1755 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
1756 | .owner = THIS_MODULE |
1757 | }; | |
1758 | ||
1759 | EXPORT_SYMBOL(dm_get_mapinfo); | |
1760 | ||
1761 | /* | |
1762 | * module hooks | |
1763 | */ | |
1764 | module_init(dm_init); | |
1765 | module_exit(dm_exit); | |
1766 | ||
1767 | module_param(major, uint, 0); | |
1768 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
1769 | MODULE_DESCRIPTION(DM_NAME " driver"); | |
1770 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
1771 | MODULE_LICENSE("GPL"); |