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 | */ | |
1eb787ec | 92 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
1da177e4 | 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 |
1eb787ec | 98 | #define DMF_QUEUE_IO_TO_THREAD 6 |
1da177e4 | 99 | |
304f3f6a MB |
100 | /* |
101 | * Work processed by per-device workqueue. | |
102 | */ | |
1da177e4 | 103 | struct mapped_device { |
2ca3310e | 104 | struct rw_semaphore io_lock; |
e61290a4 | 105 | struct mutex suspend_lock; |
1da177e4 LT |
106 | rwlock_t map_lock; |
107 | atomic_t holders; | |
5c6bd75d | 108 | atomic_t open_count; |
1da177e4 LT |
109 | |
110 | unsigned long flags; | |
111 | ||
165125e1 | 112 | struct request_queue *queue; |
1da177e4 | 113 | struct gendisk *disk; |
7e51f257 | 114 | char name[16]; |
1da177e4 LT |
115 | |
116 | void *interface_ptr; | |
117 | ||
118 | /* | |
119 | * A list of ios that arrived while we were suspended. | |
120 | */ | |
121 | atomic_t pending; | |
122 | wait_queue_head_t wait; | |
53d5914f | 123 | struct work_struct work; |
74859364 | 124 | struct bio_list deferred; |
022c2611 | 125 | spinlock_t deferred_lock; |
1da177e4 | 126 | |
304f3f6a MB |
127 | /* |
128 | * Processing queue (flush/barriers) | |
129 | */ | |
130 | struct workqueue_struct *wq; | |
131 | ||
1da177e4 LT |
132 | /* |
133 | * The current mapping. | |
134 | */ | |
135 | struct dm_table *map; | |
136 | ||
137 | /* | |
138 | * io objects are allocated from here. | |
139 | */ | |
140 | mempool_t *io_pool; | |
141 | mempool_t *tio_pool; | |
142 | ||
9faf400f SB |
143 | struct bio_set *bs; |
144 | ||
1da177e4 LT |
145 | /* |
146 | * Event handling. | |
147 | */ | |
148 | atomic_t event_nr; | |
149 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
150 | atomic_t uevent_seq; |
151 | struct list_head uevent_list; | |
152 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
153 | |
154 | /* | |
155 | * freeze/thaw support require holding onto a super block | |
156 | */ | |
157 | struct super_block *frozen_sb; | |
e39e2e95 | 158 | struct block_device *suspended_bdev; |
3ac51e74 DW |
159 | |
160 | /* forced geometry settings */ | |
161 | struct hd_geometry geometry; | |
784aae73 MB |
162 | |
163 | /* sysfs handle */ | |
164 | struct kobject kobj; | |
1da177e4 LT |
165 | }; |
166 | ||
167 | #define MIN_IOS 256 | |
e18b890b CL |
168 | static struct kmem_cache *_io_cache; |
169 | static struct kmem_cache *_tio_cache; | |
8fbf26ad KU |
170 | static struct kmem_cache *_rq_tio_cache; |
171 | static struct kmem_cache *_rq_bio_info_cache; | |
1da177e4 | 172 | |
1da177e4 LT |
173 | static int __init local_init(void) |
174 | { | |
51157b4a | 175 | int r = -ENOMEM; |
1da177e4 | 176 | |
1da177e4 | 177 | /* allocate a slab for the dm_ios */ |
028867ac | 178 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 | 179 | if (!_io_cache) |
51157b4a | 180 | return r; |
1da177e4 LT |
181 | |
182 | /* allocate a slab for the target ios */ | |
028867ac | 183 | _tio_cache = KMEM_CACHE(dm_target_io, 0); |
51157b4a KU |
184 | if (!_tio_cache) |
185 | goto out_free_io_cache; | |
1da177e4 | 186 | |
8fbf26ad KU |
187 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
188 | if (!_rq_tio_cache) | |
189 | goto out_free_tio_cache; | |
190 | ||
191 | _rq_bio_info_cache = KMEM_CACHE(dm_rq_clone_bio_info, 0); | |
192 | if (!_rq_bio_info_cache) | |
193 | goto out_free_rq_tio_cache; | |
194 | ||
51e5b2bd | 195 | r = dm_uevent_init(); |
51157b4a | 196 | if (r) |
8fbf26ad | 197 | goto out_free_rq_bio_info_cache; |
51e5b2bd | 198 | |
1da177e4 LT |
199 | _major = major; |
200 | r = register_blkdev(_major, _name); | |
51157b4a KU |
201 | if (r < 0) |
202 | goto out_uevent_exit; | |
1da177e4 LT |
203 | |
204 | if (!_major) | |
205 | _major = r; | |
206 | ||
207 | return 0; | |
51157b4a KU |
208 | |
209 | out_uevent_exit: | |
210 | dm_uevent_exit(); | |
8fbf26ad KU |
211 | out_free_rq_bio_info_cache: |
212 | kmem_cache_destroy(_rq_bio_info_cache); | |
213 | out_free_rq_tio_cache: | |
214 | kmem_cache_destroy(_rq_tio_cache); | |
51157b4a KU |
215 | out_free_tio_cache: |
216 | kmem_cache_destroy(_tio_cache); | |
217 | out_free_io_cache: | |
218 | kmem_cache_destroy(_io_cache); | |
219 | ||
220 | return r; | |
1da177e4 LT |
221 | } |
222 | ||
223 | static void local_exit(void) | |
224 | { | |
8fbf26ad KU |
225 | kmem_cache_destroy(_rq_bio_info_cache); |
226 | kmem_cache_destroy(_rq_tio_cache); | |
1da177e4 LT |
227 | kmem_cache_destroy(_tio_cache); |
228 | kmem_cache_destroy(_io_cache); | |
00d59405 | 229 | unregister_blkdev(_major, _name); |
51e5b2bd | 230 | dm_uevent_exit(); |
1da177e4 LT |
231 | |
232 | _major = 0; | |
233 | ||
234 | DMINFO("cleaned up"); | |
235 | } | |
236 | ||
b9249e55 | 237 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
238 | local_init, |
239 | dm_target_init, | |
240 | dm_linear_init, | |
241 | dm_stripe_init, | |
945fa4d2 | 242 | dm_kcopyd_init, |
1da177e4 LT |
243 | dm_interface_init, |
244 | }; | |
245 | ||
b9249e55 | 246 | static void (*_exits[])(void) = { |
1da177e4 LT |
247 | local_exit, |
248 | dm_target_exit, | |
249 | dm_linear_exit, | |
250 | dm_stripe_exit, | |
945fa4d2 | 251 | dm_kcopyd_exit, |
1da177e4 LT |
252 | dm_interface_exit, |
253 | }; | |
254 | ||
255 | static int __init dm_init(void) | |
256 | { | |
257 | const int count = ARRAY_SIZE(_inits); | |
258 | ||
259 | int r, i; | |
260 | ||
261 | for (i = 0; i < count; i++) { | |
262 | r = _inits[i](); | |
263 | if (r) | |
264 | goto bad; | |
265 | } | |
266 | ||
267 | return 0; | |
268 | ||
269 | bad: | |
270 | while (i--) | |
271 | _exits[i](); | |
272 | ||
273 | return r; | |
274 | } | |
275 | ||
276 | static void __exit dm_exit(void) | |
277 | { | |
278 | int i = ARRAY_SIZE(_exits); | |
279 | ||
280 | while (i--) | |
281 | _exits[i](); | |
282 | } | |
283 | ||
284 | /* | |
285 | * Block device functions | |
286 | */ | |
fe5f9f2c | 287 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
288 | { |
289 | struct mapped_device *md; | |
290 | ||
fba9f90e JM |
291 | spin_lock(&_minor_lock); |
292 | ||
fe5f9f2c | 293 | md = bdev->bd_disk->private_data; |
fba9f90e JM |
294 | if (!md) |
295 | goto out; | |
296 | ||
5c6bd75d AK |
297 | if (test_bit(DMF_FREEING, &md->flags) || |
298 | test_bit(DMF_DELETING, &md->flags)) { | |
fba9f90e JM |
299 | md = NULL; |
300 | goto out; | |
301 | } | |
302 | ||
1da177e4 | 303 | dm_get(md); |
5c6bd75d | 304 | atomic_inc(&md->open_count); |
fba9f90e JM |
305 | |
306 | out: | |
307 | spin_unlock(&_minor_lock); | |
308 | ||
309 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
310 | } |
311 | ||
fe5f9f2c | 312 | static int dm_blk_close(struct gendisk *disk, fmode_t mode) |
1da177e4 | 313 | { |
fe5f9f2c | 314 | struct mapped_device *md = disk->private_data; |
5c6bd75d | 315 | atomic_dec(&md->open_count); |
1da177e4 LT |
316 | dm_put(md); |
317 | return 0; | |
318 | } | |
319 | ||
5c6bd75d AK |
320 | int dm_open_count(struct mapped_device *md) |
321 | { | |
322 | return atomic_read(&md->open_count); | |
323 | } | |
324 | ||
325 | /* | |
326 | * Guarantees nothing is using the device before it's deleted. | |
327 | */ | |
328 | int dm_lock_for_deletion(struct mapped_device *md) | |
329 | { | |
330 | int r = 0; | |
331 | ||
332 | spin_lock(&_minor_lock); | |
333 | ||
334 | if (dm_open_count(md)) | |
335 | r = -EBUSY; | |
336 | else | |
337 | set_bit(DMF_DELETING, &md->flags); | |
338 | ||
339 | spin_unlock(&_minor_lock); | |
340 | ||
341 | return r; | |
342 | } | |
343 | ||
3ac51e74 DW |
344 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
345 | { | |
346 | struct mapped_device *md = bdev->bd_disk->private_data; | |
347 | ||
348 | return dm_get_geometry(md, geo); | |
349 | } | |
350 | ||
fe5f9f2c | 351 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
aa129a22 MB |
352 | unsigned int cmd, unsigned long arg) |
353 | { | |
fe5f9f2c AV |
354 | struct mapped_device *md = bdev->bd_disk->private_data; |
355 | struct dm_table *map = dm_get_table(md); | |
aa129a22 MB |
356 | struct dm_target *tgt; |
357 | int r = -ENOTTY; | |
358 | ||
aa129a22 MB |
359 | if (!map || !dm_table_get_size(map)) |
360 | goto out; | |
361 | ||
362 | /* We only support devices that have a single target */ | |
363 | if (dm_table_get_num_targets(map) != 1) | |
364 | goto out; | |
365 | ||
366 | tgt = dm_table_get_target(map, 0); | |
367 | ||
368 | if (dm_suspended(md)) { | |
369 | r = -EAGAIN; | |
370 | goto out; | |
371 | } | |
372 | ||
373 | if (tgt->type->ioctl) | |
647b3d00 | 374 | r = tgt->type->ioctl(tgt, cmd, arg); |
aa129a22 MB |
375 | |
376 | out: | |
377 | dm_table_put(map); | |
378 | ||
aa129a22 MB |
379 | return r; |
380 | } | |
381 | ||
028867ac | 382 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
383 | { |
384 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
385 | } | |
386 | ||
028867ac | 387 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
388 | { |
389 | mempool_free(io, md->io_pool); | |
390 | } | |
391 | ||
028867ac | 392 | static struct dm_target_io *alloc_tio(struct mapped_device *md) |
1da177e4 LT |
393 | { |
394 | return mempool_alloc(md->tio_pool, GFP_NOIO); | |
395 | } | |
396 | ||
028867ac | 397 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 LT |
398 | { |
399 | mempool_free(tio, md->tio_pool); | |
400 | } | |
401 | ||
3eaf840e JNN |
402 | static void start_io_acct(struct dm_io *io) |
403 | { | |
404 | struct mapped_device *md = io->md; | |
c9959059 | 405 | int cpu; |
3eaf840e JNN |
406 | |
407 | io->start_time = jiffies; | |
408 | ||
074a7aca TH |
409 | cpu = part_stat_lock(); |
410 | part_round_stats(cpu, &dm_disk(md)->part0); | |
411 | part_stat_unlock(); | |
412 | dm_disk(md)->part0.in_flight = atomic_inc_return(&md->pending); | |
3eaf840e JNN |
413 | } |
414 | ||
d221d2e7 | 415 | static void end_io_acct(struct dm_io *io) |
3eaf840e JNN |
416 | { |
417 | struct mapped_device *md = io->md; | |
418 | struct bio *bio = io->bio; | |
419 | unsigned long duration = jiffies - io->start_time; | |
c9959059 | 420 | int pending, cpu; |
3eaf840e JNN |
421 | int rw = bio_data_dir(bio); |
422 | ||
074a7aca TH |
423 | cpu = part_stat_lock(); |
424 | part_round_stats(cpu, &dm_disk(md)->part0); | |
425 | part_stat_add(cpu, &dm_disk(md)->part0, ticks[rw], duration); | |
426 | part_stat_unlock(); | |
3eaf840e | 427 | |
074a7aca TH |
428 | dm_disk(md)->part0.in_flight = pending = |
429 | atomic_dec_return(&md->pending); | |
3eaf840e | 430 | |
d221d2e7 MP |
431 | /* nudge anyone waiting on suspend queue */ |
432 | if (!pending) | |
433 | wake_up(&md->wait); | |
3eaf840e JNN |
434 | } |
435 | ||
1da177e4 LT |
436 | /* |
437 | * Add the bio to the list of deferred io. | |
438 | */ | |
439 | static int queue_io(struct mapped_device *md, struct bio *bio) | |
440 | { | |
2ca3310e | 441 | down_write(&md->io_lock); |
1da177e4 | 442 | |
1eb787ec | 443 | if (!test_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags)) { |
2ca3310e | 444 | up_write(&md->io_lock); |
1da177e4 LT |
445 | return 1; |
446 | } | |
447 | ||
022c2611 | 448 | spin_lock_irq(&md->deferred_lock); |
1da177e4 | 449 | bio_list_add(&md->deferred, bio); |
022c2611 | 450 | spin_unlock_irq(&md->deferred_lock); |
1da177e4 | 451 | |
2ca3310e | 452 | up_write(&md->io_lock); |
1da177e4 LT |
453 | return 0; /* deferred successfully */ |
454 | } | |
455 | ||
456 | /* | |
457 | * Everyone (including functions in this file), should use this | |
458 | * function to access the md->map field, and make sure they call | |
459 | * dm_table_put() when finished. | |
460 | */ | |
461 | struct dm_table *dm_get_table(struct mapped_device *md) | |
462 | { | |
463 | struct dm_table *t; | |
464 | ||
465 | read_lock(&md->map_lock); | |
466 | t = md->map; | |
467 | if (t) | |
468 | dm_table_get(t); | |
469 | read_unlock(&md->map_lock); | |
470 | ||
471 | return t; | |
472 | } | |
473 | ||
3ac51e74 DW |
474 | /* |
475 | * Get the geometry associated with a dm device | |
476 | */ | |
477 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
478 | { | |
479 | *geo = md->geometry; | |
480 | ||
481 | return 0; | |
482 | } | |
483 | ||
484 | /* | |
485 | * Set the geometry of a device. | |
486 | */ | |
487 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
488 | { | |
489 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
490 | ||
491 | if (geo->start > sz) { | |
492 | DMWARN("Start sector is beyond the geometry limits."); | |
493 | return -EINVAL; | |
494 | } | |
495 | ||
496 | md->geometry = *geo; | |
497 | ||
498 | return 0; | |
499 | } | |
500 | ||
1da177e4 LT |
501 | /*----------------------------------------------------------------- |
502 | * CRUD START: | |
503 | * A more elegant soln is in the works that uses the queue | |
504 | * merge fn, unfortunately there are a couple of changes to | |
505 | * the block layer that I want to make for this. So in the | |
506 | * interests of getting something for people to use I give | |
507 | * you this clearly demarcated crap. | |
508 | *---------------------------------------------------------------*/ | |
509 | ||
2e93ccc1 KU |
510 | static int __noflush_suspending(struct mapped_device *md) |
511 | { | |
512 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
513 | } | |
514 | ||
1da177e4 LT |
515 | /* |
516 | * Decrements the number of outstanding ios that a bio has been | |
517 | * cloned into, completing the original io if necc. | |
518 | */ | |
858119e1 | 519 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 520 | { |
2e93ccc1 | 521 | unsigned long flags; |
b35f8caa MB |
522 | int io_error; |
523 | struct bio *bio; | |
524 | struct mapped_device *md = io->md; | |
2e93ccc1 KU |
525 | |
526 | /* Push-back supersedes any I/O errors */ | |
b35f8caa | 527 | if (error && !(io->error > 0 && __noflush_suspending(md))) |
1da177e4 LT |
528 | io->error = error; |
529 | ||
530 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
531 | if (io->error == DM_ENDIO_REQUEUE) { |
532 | /* | |
533 | * Target requested pushing back the I/O. | |
2e93ccc1 | 534 | */ |
022c2611 | 535 | spin_lock_irqsave(&md->deferred_lock, flags); |
b35f8caa | 536 | if (__noflush_suspending(md)) |
022c2611 | 537 | bio_list_add(&md->deferred, io->bio); |
2e93ccc1 KU |
538 | else |
539 | /* noflush suspend was interrupted. */ | |
540 | io->error = -EIO; | |
022c2611 | 541 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
2e93ccc1 KU |
542 | } |
543 | ||
d221d2e7 | 544 | end_io_acct(io); |
1da177e4 | 545 | |
b35f8caa MB |
546 | io_error = io->error; |
547 | bio = io->bio; | |
2e93ccc1 | 548 | |
b35f8caa MB |
549 | free_io(md, io); |
550 | ||
551 | if (io_error != DM_ENDIO_REQUEUE) { | |
552 | trace_block_bio_complete(md->queue, bio); | |
2056a782 | 553 | |
b35f8caa MB |
554 | bio_endio(bio, io_error); |
555 | } | |
1da177e4 LT |
556 | } |
557 | } | |
558 | ||
6712ecf8 | 559 | static void clone_endio(struct bio *bio, int error) |
1da177e4 LT |
560 | { |
561 | int r = 0; | |
028867ac | 562 | struct dm_target_io *tio = bio->bi_private; |
b35f8caa | 563 | struct dm_io *io = tio->io; |
9faf400f | 564 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
565 | dm_endio_fn endio = tio->ti->type->end_io; |
566 | ||
1da177e4 LT |
567 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
568 | error = -EIO; | |
569 | ||
570 | if (endio) { | |
571 | r = endio(tio->ti, bio, error, &tio->info); | |
2e93ccc1 KU |
572 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
573 | /* | |
574 | * error and requeue request are handled | |
575 | * in dec_pending(). | |
576 | */ | |
1da177e4 | 577 | error = r; |
45cbcd79 KU |
578 | else if (r == DM_ENDIO_INCOMPLETE) |
579 | /* The target will handle the io */ | |
6712ecf8 | 580 | return; |
45cbcd79 KU |
581 | else if (r) { |
582 | DMWARN("unimplemented target endio return value: %d", r); | |
583 | BUG(); | |
584 | } | |
1da177e4 LT |
585 | } |
586 | ||
9faf400f SB |
587 | /* |
588 | * Store md for cleanup instead of tio which is about to get freed. | |
589 | */ | |
590 | bio->bi_private = md->bs; | |
591 | ||
9faf400f | 592 | free_tio(md, tio); |
b35f8caa MB |
593 | bio_put(bio); |
594 | dec_pending(io, error); | |
1da177e4 LT |
595 | } |
596 | ||
597 | static sector_t max_io_len(struct mapped_device *md, | |
598 | sector_t sector, struct dm_target *ti) | |
599 | { | |
600 | sector_t offset = sector - ti->begin; | |
601 | sector_t len = ti->len - offset; | |
602 | ||
603 | /* | |
604 | * Does the target need to split even further ? | |
605 | */ | |
606 | if (ti->split_io) { | |
607 | sector_t boundary; | |
608 | boundary = ((offset + ti->split_io) & ~(ti->split_io - 1)) | |
609 | - offset; | |
610 | if (len > boundary) | |
611 | len = boundary; | |
612 | } | |
613 | ||
614 | return len; | |
615 | } | |
616 | ||
617 | static void __map_bio(struct dm_target *ti, struct bio *clone, | |
028867ac | 618 | struct dm_target_io *tio) |
1da177e4 LT |
619 | { |
620 | int r; | |
2056a782 | 621 | sector_t sector; |
9faf400f | 622 | struct mapped_device *md; |
1da177e4 LT |
623 | |
624 | /* | |
625 | * Sanity checks. | |
626 | */ | |
627 | BUG_ON(!clone->bi_size); | |
628 | ||
629 | clone->bi_end_io = clone_endio; | |
630 | clone->bi_private = tio; | |
631 | ||
632 | /* | |
633 | * Map the clone. If r == 0 we don't need to do | |
634 | * anything, the target has assumed ownership of | |
635 | * this io. | |
636 | */ | |
637 | atomic_inc(&tio->io->io_count); | |
2056a782 | 638 | sector = clone->bi_sector; |
1da177e4 | 639 | r = ti->type->map(ti, clone, &tio->info); |
45cbcd79 | 640 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 641 | /* the bio has been remapped so dispatch it */ |
2056a782 | 642 | |
5f3ea37c | 643 | trace_block_remap(bdev_get_queue(clone->bi_bdev), clone, |
c7149d6b AB |
644 | tio->io->bio->bi_bdev->bd_dev, |
645 | clone->bi_sector, sector); | |
2056a782 | 646 | |
1da177e4 | 647 | generic_make_request(clone); |
2e93ccc1 KU |
648 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
649 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
650 | md = tio->io->md; |
651 | dec_pending(tio->io, r); | |
652 | /* | |
653 | * Store bio_set for cleanup. | |
654 | */ | |
655 | clone->bi_private = md->bs; | |
1da177e4 | 656 | bio_put(clone); |
9faf400f | 657 | free_tio(md, tio); |
45cbcd79 KU |
658 | } else if (r) { |
659 | DMWARN("unimplemented target map return value: %d", r); | |
660 | BUG(); | |
1da177e4 LT |
661 | } |
662 | } | |
663 | ||
664 | struct clone_info { | |
665 | struct mapped_device *md; | |
666 | struct dm_table *map; | |
667 | struct bio *bio; | |
668 | struct dm_io *io; | |
669 | sector_t sector; | |
670 | sector_t sector_count; | |
671 | unsigned short idx; | |
672 | }; | |
673 | ||
3676347a PO |
674 | static void dm_bio_destructor(struct bio *bio) |
675 | { | |
9faf400f SB |
676 | struct bio_set *bs = bio->bi_private; |
677 | ||
678 | bio_free(bio, bs); | |
3676347a PO |
679 | } |
680 | ||
1da177e4 LT |
681 | /* |
682 | * Creates a little bio that is just does part of a bvec. | |
683 | */ | |
684 | static struct bio *split_bvec(struct bio *bio, sector_t sector, | |
685 | unsigned short idx, unsigned int offset, | |
9faf400f | 686 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
687 | { |
688 | struct bio *clone; | |
689 | struct bio_vec *bv = bio->bi_io_vec + idx; | |
690 | ||
9faf400f | 691 | clone = bio_alloc_bioset(GFP_NOIO, 1, bs); |
3676347a | 692 | clone->bi_destructor = dm_bio_destructor; |
1da177e4 LT |
693 | *clone->bi_io_vec = *bv; |
694 | ||
695 | clone->bi_sector = sector; | |
696 | clone->bi_bdev = bio->bi_bdev; | |
697 | clone->bi_rw = bio->bi_rw; | |
698 | clone->bi_vcnt = 1; | |
699 | clone->bi_size = to_bytes(len); | |
700 | clone->bi_io_vec->bv_offset = offset; | |
701 | clone->bi_io_vec->bv_len = clone->bi_size; | |
f3e1d26e | 702 | clone->bi_flags |= 1 << BIO_CLONED; |
1da177e4 | 703 | |
9c47008d MP |
704 | if (bio_integrity(bio)) { |
705 | bio_integrity_clone(clone, bio, GFP_NOIO); | |
706 | bio_integrity_trim(clone, | |
707 | bio_sector_offset(bio, idx, offset), len); | |
708 | } | |
709 | ||
1da177e4 LT |
710 | return clone; |
711 | } | |
712 | ||
713 | /* | |
714 | * Creates a bio that consists of range of complete bvecs. | |
715 | */ | |
716 | static struct bio *clone_bio(struct bio *bio, sector_t sector, | |
717 | unsigned short idx, unsigned short bv_count, | |
9faf400f | 718 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
719 | { |
720 | struct bio *clone; | |
721 | ||
9faf400f SB |
722 | clone = bio_alloc_bioset(GFP_NOIO, bio->bi_max_vecs, bs); |
723 | __bio_clone(clone, bio); | |
724 | clone->bi_destructor = dm_bio_destructor; | |
1da177e4 LT |
725 | clone->bi_sector = sector; |
726 | clone->bi_idx = idx; | |
727 | clone->bi_vcnt = idx + bv_count; | |
728 | clone->bi_size = to_bytes(len); | |
729 | clone->bi_flags &= ~(1 << BIO_SEG_VALID); | |
730 | ||
9c47008d MP |
731 | if (bio_integrity(bio)) { |
732 | bio_integrity_clone(clone, bio, GFP_NOIO); | |
733 | ||
734 | if (idx != bio->bi_idx || clone->bi_size < bio->bi_size) | |
735 | bio_integrity_trim(clone, | |
736 | bio_sector_offset(bio, idx, 0), len); | |
737 | } | |
738 | ||
1da177e4 LT |
739 | return clone; |
740 | } | |
741 | ||
512875bd | 742 | static int __clone_and_map(struct clone_info *ci) |
1da177e4 LT |
743 | { |
744 | struct bio *clone, *bio = ci->bio; | |
512875bd JN |
745 | struct dm_target *ti; |
746 | sector_t len = 0, max; | |
028867ac | 747 | struct dm_target_io *tio; |
1da177e4 | 748 | |
512875bd JN |
749 | ti = dm_table_find_target(ci->map, ci->sector); |
750 | if (!dm_target_is_valid(ti)) | |
751 | return -EIO; | |
752 | ||
753 | max = max_io_len(ci->md, ci->sector, ti); | |
754 | ||
1da177e4 LT |
755 | /* |
756 | * Allocate a target io object. | |
757 | */ | |
758 | tio = alloc_tio(ci->md); | |
759 | tio->io = ci->io; | |
760 | tio->ti = ti; | |
761 | memset(&tio->info, 0, sizeof(tio->info)); | |
762 | ||
763 | if (ci->sector_count <= max) { | |
764 | /* | |
765 | * Optimise for the simple case where we can do all of | |
766 | * the remaining io with a single clone. | |
767 | */ | |
768 | clone = clone_bio(bio, ci->sector, ci->idx, | |
9faf400f SB |
769 | bio->bi_vcnt - ci->idx, ci->sector_count, |
770 | ci->md->bs); | |
1da177e4 LT |
771 | __map_bio(ti, clone, tio); |
772 | ci->sector_count = 0; | |
773 | ||
774 | } else if (to_sector(bio->bi_io_vec[ci->idx].bv_len) <= max) { | |
775 | /* | |
776 | * There are some bvecs that don't span targets. | |
777 | * Do as many of these as possible. | |
778 | */ | |
779 | int i; | |
780 | sector_t remaining = max; | |
781 | sector_t bv_len; | |
782 | ||
783 | for (i = ci->idx; remaining && (i < bio->bi_vcnt); i++) { | |
784 | bv_len = to_sector(bio->bi_io_vec[i].bv_len); | |
785 | ||
786 | if (bv_len > remaining) | |
787 | break; | |
788 | ||
789 | remaining -= bv_len; | |
790 | len += bv_len; | |
791 | } | |
792 | ||
9faf400f SB |
793 | clone = clone_bio(bio, ci->sector, ci->idx, i - ci->idx, len, |
794 | ci->md->bs); | |
1da177e4 LT |
795 | __map_bio(ti, clone, tio); |
796 | ||
797 | ci->sector += len; | |
798 | ci->sector_count -= len; | |
799 | ci->idx = i; | |
800 | ||
801 | } else { | |
802 | /* | |
d2044a94 | 803 | * Handle a bvec that must be split between two or more targets. |
1da177e4 LT |
804 | */ |
805 | struct bio_vec *bv = bio->bi_io_vec + ci->idx; | |
d2044a94 AK |
806 | sector_t remaining = to_sector(bv->bv_len); |
807 | unsigned int offset = 0; | |
1da177e4 | 808 | |
d2044a94 AK |
809 | do { |
810 | if (offset) { | |
811 | ti = dm_table_find_target(ci->map, ci->sector); | |
512875bd JN |
812 | if (!dm_target_is_valid(ti)) |
813 | return -EIO; | |
814 | ||
d2044a94 | 815 | max = max_io_len(ci->md, ci->sector, ti); |
1da177e4 | 816 | |
d2044a94 AK |
817 | tio = alloc_tio(ci->md); |
818 | tio->io = ci->io; | |
819 | tio->ti = ti; | |
820 | memset(&tio->info, 0, sizeof(tio->info)); | |
821 | } | |
822 | ||
823 | len = min(remaining, max); | |
824 | ||
825 | clone = split_bvec(bio, ci->sector, ci->idx, | |
9faf400f SB |
826 | bv->bv_offset + offset, len, |
827 | ci->md->bs); | |
d2044a94 AK |
828 | |
829 | __map_bio(ti, clone, tio); | |
830 | ||
831 | ci->sector += len; | |
832 | ci->sector_count -= len; | |
833 | offset += to_bytes(len); | |
834 | } while (remaining -= len); | |
1da177e4 | 835 | |
1da177e4 LT |
836 | ci->idx++; |
837 | } | |
512875bd JN |
838 | |
839 | return 0; | |
1da177e4 LT |
840 | } |
841 | ||
842 | /* | |
8a53c28d | 843 | * Split the bio into several clones and submit it to targets. |
1da177e4 | 844 | */ |
f0b9a450 | 845 | static void __split_and_process_bio(struct mapped_device *md, struct bio *bio) |
1da177e4 LT |
846 | { |
847 | struct clone_info ci; | |
512875bd | 848 | int error = 0; |
1da177e4 LT |
849 | |
850 | ci.map = dm_get_table(md); | |
f0b9a450 MP |
851 | if (unlikely(!ci.map)) { |
852 | bio_io_error(bio); | |
853 | return; | |
854 | } | |
692d0eb9 | 855 | |
1da177e4 LT |
856 | ci.md = md; |
857 | ci.bio = bio; | |
858 | ci.io = alloc_io(md); | |
859 | ci.io->error = 0; | |
860 | atomic_set(&ci.io->io_count, 1); | |
861 | ci.io->bio = bio; | |
862 | ci.io->md = md; | |
863 | ci.sector = bio->bi_sector; | |
864 | ci.sector_count = bio_sectors(bio); | |
865 | ci.idx = bio->bi_idx; | |
866 | ||
3eaf840e | 867 | start_io_acct(ci.io); |
512875bd JN |
868 | while (ci.sector_count && !error) |
869 | error = __clone_and_map(&ci); | |
1da177e4 LT |
870 | |
871 | /* drop the extra reference count */ | |
512875bd | 872 | dec_pending(ci.io, error); |
1da177e4 LT |
873 | dm_table_put(ci.map); |
874 | } | |
875 | /*----------------------------------------------------------------- | |
876 | * CRUD END | |
877 | *---------------------------------------------------------------*/ | |
878 | ||
f6fccb12 MB |
879 | static int dm_merge_bvec(struct request_queue *q, |
880 | struct bvec_merge_data *bvm, | |
881 | struct bio_vec *biovec) | |
882 | { | |
883 | struct mapped_device *md = q->queuedata; | |
884 | struct dm_table *map = dm_get_table(md); | |
885 | struct dm_target *ti; | |
886 | sector_t max_sectors; | |
5037108a | 887 | int max_size = 0; |
f6fccb12 MB |
888 | |
889 | if (unlikely(!map)) | |
5037108a | 890 | goto out; |
f6fccb12 MB |
891 | |
892 | ti = dm_table_find_target(map, bvm->bi_sector); | |
b01cd5ac MP |
893 | if (!dm_target_is_valid(ti)) |
894 | goto out_table; | |
f6fccb12 MB |
895 | |
896 | /* | |
897 | * Find maximum amount of I/O that won't need splitting | |
898 | */ | |
899 | max_sectors = min(max_io_len(md, bvm->bi_sector, ti), | |
900 | (sector_t) BIO_MAX_SECTORS); | |
901 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; | |
902 | if (max_size < 0) | |
903 | max_size = 0; | |
904 | ||
905 | /* | |
906 | * merge_bvec_fn() returns number of bytes | |
907 | * it can accept at this offset | |
908 | * max is precomputed maximal io size | |
909 | */ | |
910 | if (max_size && ti->type->merge) | |
911 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
912 | ||
b01cd5ac | 913 | out_table: |
5037108a MP |
914 | dm_table_put(map); |
915 | ||
916 | out: | |
f6fccb12 MB |
917 | /* |
918 | * Always allow an entire first page | |
919 | */ | |
920 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
921 | max_size = biovec->bv_len; | |
922 | ||
f6fccb12 MB |
923 | return max_size; |
924 | } | |
925 | ||
1da177e4 LT |
926 | /* |
927 | * The request function that just remaps the bio built up by | |
928 | * dm_merge_bvec. | |
929 | */ | |
165125e1 | 930 | static int dm_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 931 | { |
9e4e5f87 | 932 | int r = -EIO; |
12f03a49 | 933 | int rw = bio_data_dir(bio); |
1da177e4 | 934 | struct mapped_device *md = q->queuedata; |
c9959059 | 935 | int cpu; |
1da177e4 | 936 | |
692d0eb9 MP |
937 | /* |
938 | * There is no use in forwarding any barrier request since we can't | |
939 | * guarantee it is (or can be) handled by the targets correctly. | |
940 | */ | |
941 | if (unlikely(bio_barrier(bio))) { | |
942 | bio_endio(bio, -EOPNOTSUPP); | |
943 | return 0; | |
944 | } | |
945 | ||
2ca3310e | 946 | down_read(&md->io_lock); |
1da177e4 | 947 | |
074a7aca TH |
948 | cpu = part_stat_lock(); |
949 | part_stat_inc(cpu, &dm_disk(md)->part0, ios[rw]); | |
950 | part_stat_add(cpu, &dm_disk(md)->part0, sectors[rw], bio_sectors(bio)); | |
951 | part_stat_unlock(); | |
12f03a49 | 952 | |
1da177e4 | 953 | /* |
1eb787ec AK |
954 | * If we're suspended or the thread is processing barriers |
955 | * we have to queue this io for later. | |
1da177e4 | 956 | */ |
1eb787ec | 957 | while (test_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags)) { |
2ca3310e | 958 | up_read(&md->io_lock); |
1da177e4 | 959 | |
9e4e5f87 MB |
960 | if (bio_rw(bio) != READA) |
961 | r = queue_io(md, bio); | |
1da177e4 | 962 | |
9e4e5f87 MB |
963 | if (r <= 0) |
964 | goto out_req; | |
1da177e4 LT |
965 | |
966 | /* | |
967 | * We're in a while loop, because someone could suspend | |
968 | * before we get to the following read lock. | |
969 | */ | |
2ca3310e | 970 | down_read(&md->io_lock); |
1da177e4 LT |
971 | } |
972 | ||
f0b9a450 | 973 | __split_and_process_bio(md, bio); |
2ca3310e | 974 | up_read(&md->io_lock); |
f0b9a450 | 975 | return 0; |
9e4e5f87 MB |
976 | |
977 | out_req: | |
978 | if (r < 0) | |
979 | bio_io_error(bio); | |
980 | ||
1da177e4 LT |
981 | return 0; |
982 | } | |
983 | ||
165125e1 | 984 | static void dm_unplug_all(struct request_queue *q) |
1da177e4 LT |
985 | { |
986 | struct mapped_device *md = q->queuedata; | |
987 | struct dm_table *map = dm_get_table(md); | |
988 | ||
989 | if (map) { | |
990 | dm_table_unplug_all(map); | |
991 | dm_table_put(map); | |
992 | } | |
993 | } | |
994 | ||
995 | static int dm_any_congested(void *congested_data, int bdi_bits) | |
996 | { | |
8a57dfc6 CS |
997 | int r = bdi_bits; |
998 | struct mapped_device *md = congested_data; | |
999 | struct dm_table *map; | |
1da177e4 | 1000 | |
1eb787ec | 1001 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
8a57dfc6 CS |
1002 | map = dm_get_table(md); |
1003 | if (map) { | |
1004 | r = dm_table_any_congested(map, bdi_bits); | |
1005 | dm_table_put(map); | |
1006 | } | |
1007 | } | |
1008 | ||
1da177e4 LT |
1009 | return r; |
1010 | } | |
1011 | ||
1012 | /*----------------------------------------------------------------- | |
1013 | * An IDR is used to keep track of allocated minor numbers. | |
1014 | *---------------------------------------------------------------*/ | |
1da177e4 LT |
1015 | static DEFINE_IDR(_minor_idr); |
1016 | ||
2b06cfff | 1017 | static void free_minor(int minor) |
1da177e4 | 1018 | { |
f32c10b0 | 1019 | spin_lock(&_minor_lock); |
1da177e4 | 1020 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 1021 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1022 | } |
1023 | ||
1024 | /* | |
1025 | * See if the device with a specific minor # is free. | |
1026 | */ | |
cf13ab8e | 1027 | static int specific_minor(int minor) |
1da177e4 LT |
1028 | { |
1029 | int r, m; | |
1030 | ||
1031 | if (minor >= (1 << MINORBITS)) | |
1032 | return -EINVAL; | |
1033 | ||
62f75c2f JM |
1034 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
1035 | if (!r) | |
1036 | return -ENOMEM; | |
1037 | ||
f32c10b0 | 1038 | spin_lock(&_minor_lock); |
1da177e4 LT |
1039 | |
1040 | if (idr_find(&_minor_idr, minor)) { | |
1041 | r = -EBUSY; | |
1042 | goto out; | |
1043 | } | |
1044 | ||
ba61fdd1 | 1045 | r = idr_get_new_above(&_minor_idr, MINOR_ALLOCED, minor, &m); |
62f75c2f | 1046 | if (r) |
1da177e4 | 1047 | goto out; |
1da177e4 LT |
1048 | |
1049 | if (m != minor) { | |
1050 | idr_remove(&_minor_idr, m); | |
1051 | r = -EBUSY; | |
1052 | goto out; | |
1053 | } | |
1054 | ||
1055 | out: | |
f32c10b0 | 1056 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1057 | return r; |
1058 | } | |
1059 | ||
cf13ab8e | 1060 | static int next_free_minor(int *minor) |
1da177e4 | 1061 | { |
2b06cfff | 1062 | int r, m; |
1da177e4 | 1063 | |
1da177e4 | 1064 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
62f75c2f JM |
1065 | if (!r) |
1066 | return -ENOMEM; | |
1067 | ||
f32c10b0 | 1068 | spin_lock(&_minor_lock); |
1da177e4 | 1069 | |
ba61fdd1 | 1070 | r = idr_get_new(&_minor_idr, MINOR_ALLOCED, &m); |
cf13ab8e | 1071 | if (r) |
1da177e4 | 1072 | goto out; |
1da177e4 LT |
1073 | |
1074 | if (m >= (1 << MINORBITS)) { | |
1075 | idr_remove(&_minor_idr, m); | |
1076 | r = -ENOSPC; | |
1077 | goto out; | |
1078 | } | |
1079 | ||
1080 | *minor = m; | |
1081 | ||
1082 | out: | |
f32c10b0 | 1083 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1084 | return r; |
1085 | } | |
1086 | ||
1087 | static struct block_device_operations dm_blk_dops; | |
1088 | ||
53d5914f MP |
1089 | static void dm_wq_work(struct work_struct *work); |
1090 | ||
1da177e4 LT |
1091 | /* |
1092 | * Allocate and initialise a blank device with a given minor. | |
1093 | */ | |
2b06cfff | 1094 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
1095 | { |
1096 | int r; | |
cf13ab8e | 1097 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 1098 | void *old_md; |
1da177e4 LT |
1099 | |
1100 | if (!md) { | |
1101 | DMWARN("unable to allocate device, out of memory."); | |
1102 | return NULL; | |
1103 | } | |
1104 | ||
10da4f79 | 1105 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 1106 | goto bad_module_get; |
10da4f79 | 1107 | |
1da177e4 | 1108 | /* get a minor number for the dev */ |
2b06cfff | 1109 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 1110 | r = next_free_minor(&minor); |
2b06cfff | 1111 | else |
cf13ab8e | 1112 | r = specific_minor(minor); |
1da177e4 | 1113 | if (r < 0) |
6ed7ade8 | 1114 | goto bad_minor; |
1da177e4 | 1115 | |
2ca3310e | 1116 | init_rwsem(&md->io_lock); |
e61290a4 | 1117 | mutex_init(&md->suspend_lock); |
022c2611 | 1118 | spin_lock_init(&md->deferred_lock); |
1da177e4 LT |
1119 | rwlock_init(&md->map_lock); |
1120 | atomic_set(&md->holders, 1); | |
5c6bd75d | 1121 | atomic_set(&md->open_count, 0); |
1da177e4 | 1122 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
1123 | atomic_set(&md->uevent_seq, 0); |
1124 | INIT_LIST_HEAD(&md->uevent_list); | |
1125 | spin_lock_init(&md->uevent_lock); | |
1da177e4 LT |
1126 | |
1127 | md->queue = blk_alloc_queue(GFP_KERNEL); | |
1128 | if (!md->queue) | |
6ed7ade8 | 1129 | goto bad_queue; |
1da177e4 LT |
1130 | |
1131 | md->queue->queuedata = md; | |
1132 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
1133 | md->queue->backing_dev_info.congested_data = md; | |
1134 | blk_queue_make_request(md->queue, dm_request); | |
99360b4c | 1135 | blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN, NULL); |
daef265f | 1136 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); |
1da177e4 | 1137 | md->queue->unplug_fn = dm_unplug_all; |
f6fccb12 | 1138 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); |
1da177e4 | 1139 | |
93d2341c | 1140 | md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache); |
74859364 | 1141 | if (!md->io_pool) |
6ed7ade8 | 1142 | goto bad_io_pool; |
1da177e4 | 1143 | |
93d2341c | 1144 | md->tio_pool = mempool_create_slab_pool(MIN_IOS, _tio_cache); |
1da177e4 | 1145 | if (!md->tio_pool) |
6ed7ade8 | 1146 | goto bad_tio_pool; |
1da177e4 | 1147 | |
bb799ca0 | 1148 | md->bs = bioset_create(16, 0); |
9faf400f SB |
1149 | if (!md->bs) |
1150 | goto bad_no_bioset; | |
1151 | ||
1da177e4 LT |
1152 | md->disk = alloc_disk(1); |
1153 | if (!md->disk) | |
6ed7ade8 | 1154 | goto bad_disk; |
1da177e4 | 1155 | |
f0b04115 JM |
1156 | atomic_set(&md->pending, 0); |
1157 | init_waitqueue_head(&md->wait); | |
53d5914f | 1158 | INIT_WORK(&md->work, dm_wq_work); |
f0b04115 JM |
1159 | init_waitqueue_head(&md->eventq); |
1160 | ||
1da177e4 LT |
1161 | md->disk->major = _major; |
1162 | md->disk->first_minor = minor; | |
1163 | md->disk->fops = &dm_blk_dops; | |
1164 | md->disk->queue = md->queue; | |
1165 | md->disk->private_data = md; | |
1166 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
1167 | add_disk(md->disk); | |
7e51f257 | 1168 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 1169 | |
304f3f6a MB |
1170 | md->wq = create_singlethread_workqueue("kdmflush"); |
1171 | if (!md->wq) | |
1172 | goto bad_thread; | |
1173 | ||
ba61fdd1 | 1174 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 1175 | spin_lock(&_minor_lock); |
ba61fdd1 | 1176 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 1177 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
1178 | |
1179 | BUG_ON(old_md != MINOR_ALLOCED); | |
1180 | ||
1da177e4 LT |
1181 | return md; |
1182 | ||
304f3f6a MB |
1183 | bad_thread: |
1184 | put_disk(md->disk); | |
6ed7ade8 | 1185 | bad_disk: |
9faf400f | 1186 | bioset_free(md->bs); |
6ed7ade8 | 1187 | bad_no_bioset: |
1da177e4 | 1188 | mempool_destroy(md->tio_pool); |
6ed7ade8 | 1189 | bad_tio_pool: |
1da177e4 | 1190 | mempool_destroy(md->io_pool); |
6ed7ade8 | 1191 | bad_io_pool: |
1312f40e | 1192 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 1193 | bad_queue: |
1da177e4 | 1194 | free_minor(minor); |
6ed7ade8 | 1195 | bad_minor: |
10da4f79 | 1196 | module_put(THIS_MODULE); |
6ed7ade8 | 1197 | bad_module_get: |
1da177e4 LT |
1198 | kfree(md); |
1199 | return NULL; | |
1200 | } | |
1201 | ||
ae9da83f JN |
1202 | static void unlock_fs(struct mapped_device *md); |
1203 | ||
1da177e4 LT |
1204 | static void free_dev(struct mapped_device *md) |
1205 | { | |
f331c029 | 1206 | int minor = MINOR(disk_devt(md->disk)); |
63d94e48 | 1207 | |
d9dde59b | 1208 | if (md->suspended_bdev) { |
ae9da83f | 1209 | unlock_fs(md); |
d9dde59b JN |
1210 | bdput(md->suspended_bdev); |
1211 | } | |
304f3f6a | 1212 | destroy_workqueue(md->wq); |
1da177e4 LT |
1213 | mempool_destroy(md->tio_pool); |
1214 | mempool_destroy(md->io_pool); | |
9faf400f | 1215 | bioset_free(md->bs); |
9c47008d | 1216 | blk_integrity_unregister(md->disk); |
1da177e4 | 1217 | del_gendisk(md->disk); |
63d94e48 | 1218 | free_minor(minor); |
fba9f90e JM |
1219 | |
1220 | spin_lock(&_minor_lock); | |
1221 | md->disk->private_data = NULL; | |
1222 | spin_unlock(&_minor_lock); | |
1223 | ||
1da177e4 | 1224 | put_disk(md->disk); |
1312f40e | 1225 | blk_cleanup_queue(md->queue); |
10da4f79 | 1226 | module_put(THIS_MODULE); |
1da177e4 LT |
1227 | kfree(md); |
1228 | } | |
1229 | ||
1230 | /* | |
1231 | * Bind a table to the device. | |
1232 | */ | |
1233 | static void event_callback(void *context) | |
1234 | { | |
7a8c3d3b MA |
1235 | unsigned long flags; |
1236 | LIST_HEAD(uevents); | |
1da177e4 LT |
1237 | struct mapped_device *md = (struct mapped_device *) context; |
1238 | ||
7a8c3d3b MA |
1239 | spin_lock_irqsave(&md->uevent_lock, flags); |
1240 | list_splice_init(&md->uevent_list, &uevents); | |
1241 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
1242 | ||
ed9e1982 | 1243 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
7a8c3d3b | 1244 | |
1da177e4 LT |
1245 | atomic_inc(&md->event_nr); |
1246 | wake_up(&md->eventq); | |
1247 | } | |
1248 | ||
4e90188b | 1249 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 1250 | { |
4e90188b | 1251 | set_capacity(md->disk, size); |
1da177e4 | 1252 | |
1b1dcc1b | 1253 | mutex_lock(&md->suspended_bdev->bd_inode->i_mutex); |
e39e2e95 | 1254 | i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
1b1dcc1b | 1255 | mutex_unlock(&md->suspended_bdev->bd_inode->i_mutex); |
1da177e4 LT |
1256 | } |
1257 | ||
1258 | static int __bind(struct mapped_device *md, struct dm_table *t) | |
1259 | { | |
165125e1 | 1260 | struct request_queue *q = md->queue; |
1da177e4 LT |
1261 | sector_t size; |
1262 | ||
1263 | size = dm_table_get_size(t); | |
3ac51e74 DW |
1264 | |
1265 | /* | |
1266 | * Wipe any geometry if the size of the table changed. | |
1267 | */ | |
1268 | if (size != get_capacity(md->disk)) | |
1269 | memset(&md->geometry, 0, sizeof(md->geometry)); | |
1270 | ||
bfa152fa JN |
1271 | if (md->suspended_bdev) |
1272 | __set_size(md, size); | |
d5816876 MP |
1273 | |
1274 | if (!size) { | |
1275 | dm_table_destroy(t); | |
1da177e4 | 1276 | return 0; |
d5816876 | 1277 | } |
1da177e4 | 1278 | |
2ca3310e AK |
1279 | dm_table_event_callback(t, event_callback, md); |
1280 | ||
1da177e4 LT |
1281 | write_lock(&md->map_lock); |
1282 | md->map = t; | |
2ca3310e | 1283 | dm_table_set_restrictions(t, q); |
1da177e4 LT |
1284 | write_unlock(&md->map_lock); |
1285 | ||
1da177e4 LT |
1286 | return 0; |
1287 | } | |
1288 | ||
1289 | static void __unbind(struct mapped_device *md) | |
1290 | { | |
1291 | struct dm_table *map = md->map; | |
1292 | ||
1293 | if (!map) | |
1294 | return; | |
1295 | ||
1296 | dm_table_event_callback(map, NULL, NULL); | |
1297 | write_lock(&md->map_lock); | |
1298 | md->map = NULL; | |
1299 | write_unlock(&md->map_lock); | |
d5816876 | 1300 | dm_table_destroy(map); |
1da177e4 LT |
1301 | } |
1302 | ||
1303 | /* | |
1304 | * Constructor for a new device. | |
1305 | */ | |
2b06cfff | 1306 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
1307 | { |
1308 | struct mapped_device *md; | |
1309 | ||
2b06cfff | 1310 | md = alloc_dev(minor); |
1da177e4 LT |
1311 | if (!md) |
1312 | return -ENXIO; | |
1313 | ||
784aae73 MB |
1314 | dm_sysfs_init(md); |
1315 | ||
1da177e4 LT |
1316 | *result = md; |
1317 | return 0; | |
1318 | } | |
1319 | ||
637842cf | 1320 | static struct mapped_device *dm_find_md(dev_t dev) |
1da177e4 LT |
1321 | { |
1322 | struct mapped_device *md; | |
1da177e4 LT |
1323 | unsigned minor = MINOR(dev); |
1324 | ||
1325 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
1326 | return NULL; | |
1327 | ||
f32c10b0 | 1328 | spin_lock(&_minor_lock); |
1da177e4 LT |
1329 | |
1330 | md = idr_find(&_minor_idr, minor); | |
fba9f90e | 1331 | if (md && (md == MINOR_ALLOCED || |
f331c029 | 1332 | (MINOR(disk_devt(dm_disk(md))) != minor) || |
17b2f66f | 1333 | test_bit(DMF_FREEING, &md->flags))) { |
637842cf | 1334 | md = NULL; |
fba9f90e JM |
1335 | goto out; |
1336 | } | |
1da177e4 | 1337 | |
fba9f90e | 1338 | out: |
f32c10b0 | 1339 | spin_unlock(&_minor_lock); |
1da177e4 | 1340 | |
637842cf DT |
1341 | return md; |
1342 | } | |
1343 | ||
d229a958 DT |
1344 | struct mapped_device *dm_get_md(dev_t dev) |
1345 | { | |
1346 | struct mapped_device *md = dm_find_md(dev); | |
1347 | ||
1348 | if (md) | |
1349 | dm_get(md); | |
1350 | ||
1351 | return md; | |
1352 | } | |
1353 | ||
9ade92a9 | 1354 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 1355 | { |
9ade92a9 | 1356 | return md->interface_ptr; |
1da177e4 LT |
1357 | } |
1358 | ||
1359 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
1360 | { | |
1361 | md->interface_ptr = ptr; | |
1362 | } | |
1363 | ||
1364 | void dm_get(struct mapped_device *md) | |
1365 | { | |
1366 | atomic_inc(&md->holders); | |
1367 | } | |
1368 | ||
72d94861 AK |
1369 | const char *dm_device_name(struct mapped_device *md) |
1370 | { | |
1371 | return md->name; | |
1372 | } | |
1373 | EXPORT_SYMBOL_GPL(dm_device_name); | |
1374 | ||
1da177e4 LT |
1375 | void dm_put(struct mapped_device *md) |
1376 | { | |
1134e5ae | 1377 | struct dm_table *map; |
1da177e4 | 1378 | |
fba9f90e JM |
1379 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
1380 | ||
f32c10b0 | 1381 | if (atomic_dec_and_lock(&md->holders, &_minor_lock)) { |
1134e5ae | 1382 | map = dm_get_table(md); |
f331c029 TH |
1383 | idr_replace(&_minor_idr, MINOR_ALLOCED, |
1384 | MINOR(disk_devt(dm_disk(md)))); | |
fba9f90e | 1385 | set_bit(DMF_FREEING, &md->flags); |
f32c10b0 | 1386 | spin_unlock(&_minor_lock); |
cf222b37 | 1387 | if (!dm_suspended(md)) { |
1da177e4 LT |
1388 | dm_table_presuspend_targets(map); |
1389 | dm_table_postsuspend_targets(map); | |
1390 | } | |
784aae73 | 1391 | dm_sysfs_exit(md); |
1134e5ae | 1392 | dm_table_put(map); |
a1b51e98 | 1393 | __unbind(md); |
1da177e4 LT |
1394 | free_dev(md); |
1395 | } | |
1da177e4 | 1396 | } |
79eb885c | 1397 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 1398 | |
401600df | 1399 | static int dm_wait_for_completion(struct mapped_device *md, int interruptible) |
46125c1c MB |
1400 | { |
1401 | int r = 0; | |
b44ebeb0 MP |
1402 | DECLARE_WAITQUEUE(wait, current); |
1403 | ||
1404 | dm_unplug_all(md->queue); | |
1405 | ||
1406 | add_wait_queue(&md->wait, &wait); | |
46125c1c MB |
1407 | |
1408 | while (1) { | |
401600df | 1409 | set_current_state(interruptible); |
46125c1c MB |
1410 | |
1411 | smp_mb(); | |
1412 | if (!atomic_read(&md->pending)) | |
1413 | break; | |
1414 | ||
401600df MP |
1415 | if (interruptible == TASK_INTERRUPTIBLE && |
1416 | signal_pending(current)) { | |
46125c1c MB |
1417 | r = -EINTR; |
1418 | break; | |
1419 | } | |
1420 | ||
1421 | io_schedule(); | |
1422 | } | |
1423 | set_current_state(TASK_RUNNING); | |
1424 | ||
b44ebeb0 MP |
1425 | remove_wait_queue(&md->wait, &wait); |
1426 | ||
46125c1c MB |
1427 | return r; |
1428 | } | |
1429 | ||
1da177e4 LT |
1430 | /* |
1431 | * Process the deferred bios | |
1432 | */ | |
ef208587 | 1433 | static void dm_wq_work(struct work_struct *work) |
1da177e4 | 1434 | { |
ef208587 MP |
1435 | struct mapped_device *md = container_of(work, struct mapped_device, |
1436 | work); | |
6d6f10df | 1437 | struct bio *c; |
1da177e4 | 1438 | |
ef208587 MP |
1439 | down_write(&md->io_lock); |
1440 | ||
df12ee99 AK |
1441 | while (1) { |
1442 | spin_lock_irq(&md->deferred_lock); | |
1443 | c = bio_list_pop(&md->deferred); | |
1444 | spin_unlock_irq(&md->deferred_lock); | |
1445 | ||
1446 | if (!c) { | |
1eb787ec AK |
1447 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
1448 | clear_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags); | |
df12ee99 AK |
1449 | break; |
1450 | } | |
022c2611 | 1451 | |
f0b9a450 | 1452 | __split_and_process_bio(md, c); |
022c2611 | 1453 | } |
73d410c0 | 1454 | |
ef208587 | 1455 | up_write(&md->io_lock); |
1da177e4 LT |
1456 | } |
1457 | ||
9a1fb464 | 1458 | static void dm_queue_flush(struct mapped_device *md) |
304f3f6a | 1459 | { |
53d5914f | 1460 | queue_work(md->wq, &md->work); |
304f3f6a MB |
1461 | flush_workqueue(md->wq); |
1462 | } | |
1463 | ||
1da177e4 LT |
1464 | /* |
1465 | * Swap in a new table (destroying old one). | |
1466 | */ | |
1467 | int dm_swap_table(struct mapped_device *md, struct dm_table *table) | |
1468 | { | |
93c534ae | 1469 | int r = -EINVAL; |
1da177e4 | 1470 | |
e61290a4 | 1471 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
1472 | |
1473 | /* device must be suspended */ | |
cf222b37 | 1474 | if (!dm_suspended(md)) |
93c534ae | 1475 | goto out; |
1da177e4 | 1476 | |
bfa152fa JN |
1477 | /* without bdev, the device size cannot be changed */ |
1478 | if (!md->suspended_bdev) | |
1479 | if (get_capacity(md->disk) != dm_table_get_size(table)) | |
1480 | goto out; | |
1481 | ||
1da177e4 LT |
1482 | __unbind(md); |
1483 | r = __bind(md, table); | |
1da177e4 | 1484 | |
93c534ae | 1485 | out: |
e61290a4 | 1486 | mutex_unlock(&md->suspend_lock); |
93c534ae | 1487 | return r; |
1da177e4 LT |
1488 | } |
1489 | ||
1490 | /* | |
1491 | * Functions to lock and unlock any filesystem running on the | |
1492 | * device. | |
1493 | */ | |
2ca3310e | 1494 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 1495 | { |
e39e2e95 | 1496 | int r; |
1da177e4 LT |
1497 | |
1498 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 1499 | |
e39e2e95 | 1500 | md->frozen_sb = freeze_bdev(md->suspended_bdev); |
dfbe03f6 | 1501 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 1502 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
1503 | md->frozen_sb = NULL; |
1504 | return r; | |
dfbe03f6 AK |
1505 | } |
1506 | ||
aa8d7c2f AK |
1507 | set_bit(DMF_FROZEN, &md->flags); |
1508 | ||
1da177e4 | 1509 | /* don't bdput right now, we don't want the bdev |
e39e2e95 | 1510 | * to go away while it is locked. |
1da177e4 LT |
1511 | */ |
1512 | return 0; | |
1513 | } | |
1514 | ||
2ca3310e | 1515 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 1516 | { |
aa8d7c2f AK |
1517 | if (!test_bit(DMF_FROZEN, &md->flags)) |
1518 | return; | |
1519 | ||
e39e2e95 | 1520 | thaw_bdev(md->suspended_bdev, md->frozen_sb); |
1da177e4 | 1521 | md->frozen_sb = NULL; |
aa8d7c2f | 1522 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
1523 | } |
1524 | ||
1525 | /* | |
1526 | * We need to be able to change a mapping table under a mounted | |
1527 | * filesystem. For example we might want to move some data in | |
1528 | * the background. Before the table can be swapped with | |
1529 | * dm_bind_table, dm_suspend must be called to flush any in | |
1530 | * flight bios and ensure that any further io gets deferred. | |
1531 | */ | |
a3d77d35 | 1532 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) |
1da177e4 | 1533 | { |
2ca3310e | 1534 | struct dm_table *map = NULL; |
46125c1c | 1535 | int r = 0; |
a3d77d35 | 1536 | int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0; |
2e93ccc1 | 1537 | int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0; |
1da177e4 | 1538 | |
e61290a4 | 1539 | mutex_lock(&md->suspend_lock); |
2ca3310e | 1540 | |
73d410c0 MB |
1541 | if (dm_suspended(md)) { |
1542 | r = -EINVAL; | |
d287483d | 1543 | goto out_unlock; |
73d410c0 | 1544 | } |
1da177e4 LT |
1545 | |
1546 | map = dm_get_table(md); | |
1da177e4 | 1547 | |
2e93ccc1 KU |
1548 | /* |
1549 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
1550 | * This flag is cleared before dm_suspend returns. | |
1551 | */ | |
1552 | if (noflush) | |
1553 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
1554 | ||
cf222b37 AK |
1555 | /* This does not get reverted if there's an error later. */ |
1556 | dm_table_presuspend_targets(map); | |
1557 | ||
bfa152fa JN |
1558 | /* bdget() can stall if the pending I/Os are not flushed */ |
1559 | if (!noflush) { | |
1560 | md->suspended_bdev = bdget_disk(md->disk, 0); | |
1561 | if (!md->suspended_bdev) { | |
1562 | DMWARN("bdget failed in dm_suspend"); | |
1563 | r = -ENOMEM; | |
f431d966 | 1564 | goto out; |
bfa152fa | 1565 | } |
e39e2e95 | 1566 | |
6d6f10df MB |
1567 | /* |
1568 | * Flush I/O to the device. noflush supersedes do_lockfs, | |
1569 | * because lock_fs() needs to flush I/Os. | |
1570 | */ | |
1571 | if (do_lockfs) { | |
1572 | r = lock_fs(md); | |
1573 | if (r) | |
1574 | goto out; | |
1575 | } | |
aa8d7c2f | 1576 | } |
1da177e4 LT |
1577 | |
1578 | /* | |
1eb787ec AK |
1579 | * First we set the DMF_QUEUE_IO_TO_THREAD flag so no more ios |
1580 | * will be mapped. | |
1da177e4 | 1581 | */ |
2ca3310e | 1582 | down_write(&md->io_lock); |
1eb787ec AK |
1583 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
1584 | set_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags); | |
1da177e4 | 1585 | |
2ca3310e | 1586 | up_write(&md->io_lock); |
1da177e4 | 1587 | |
1da177e4 | 1588 | /* |
46125c1c | 1589 | * Wait for the already-mapped ios to complete. |
1da177e4 | 1590 | */ |
401600df | 1591 | r = dm_wait_for_completion(md, TASK_INTERRUPTIBLE); |
1da177e4 | 1592 | |
2ca3310e | 1593 | down_write(&md->io_lock); |
1da177e4 | 1594 | |
6d6f10df | 1595 | if (noflush) |
022c2611 | 1596 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
94d6351e | 1597 | up_write(&md->io_lock); |
2e93ccc1 | 1598 | |
1da177e4 | 1599 | /* were we interrupted ? */ |
46125c1c | 1600 | if (r < 0) { |
9a1fb464 | 1601 | dm_queue_flush(md); |
73d410c0 | 1602 | |
2ca3310e | 1603 | unlock_fs(md); |
2e93ccc1 | 1604 | goto out; /* pushback list is already flushed, so skip flush */ |
2ca3310e | 1605 | } |
1da177e4 | 1606 | |
cf222b37 | 1607 | dm_table_postsuspend_targets(map); |
1da177e4 | 1608 | |
2ca3310e | 1609 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 1610 | |
2ca3310e | 1611 | out: |
e39e2e95 AK |
1612 | if (r && md->suspended_bdev) { |
1613 | bdput(md->suspended_bdev); | |
1614 | md->suspended_bdev = NULL; | |
1615 | } | |
1616 | ||
2ca3310e | 1617 | dm_table_put(map); |
d287483d AK |
1618 | |
1619 | out_unlock: | |
e61290a4 | 1620 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 1621 | return r; |
1da177e4 LT |
1622 | } |
1623 | ||
1624 | int dm_resume(struct mapped_device *md) | |
1625 | { | |
cf222b37 | 1626 | int r = -EINVAL; |
cf222b37 | 1627 | struct dm_table *map = NULL; |
1da177e4 | 1628 | |
e61290a4 | 1629 | mutex_lock(&md->suspend_lock); |
2ca3310e | 1630 | if (!dm_suspended(md)) |
cf222b37 | 1631 | goto out; |
cf222b37 AK |
1632 | |
1633 | map = dm_get_table(md); | |
2ca3310e | 1634 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 1635 | goto out; |
1da177e4 | 1636 | |
8757b776 MB |
1637 | r = dm_table_resume_targets(map); |
1638 | if (r) | |
1639 | goto out; | |
2ca3310e | 1640 | |
9a1fb464 | 1641 | dm_queue_flush(md); |
2ca3310e AK |
1642 | |
1643 | unlock_fs(md); | |
1644 | ||
bfa152fa JN |
1645 | if (md->suspended_bdev) { |
1646 | bdput(md->suspended_bdev); | |
1647 | md->suspended_bdev = NULL; | |
1648 | } | |
e39e2e95 | 1649 | |
2ca3310e AK |
1650 | clear_bit(DMF_SUSPENDED, &md->flags); |
1651 | ||
1da177e4 | 1652 | dm_table_unplug_all(map); |
1da177e4 | 1653 | |
69267a30 | 1654 | dm_kobject_uevent(md); |
8560ed6f | 1655 | |
cf222b37 | 1656 | r = 0; |
2ca3310e | 1657 | |
cf222b37 AK |
1658 | out: |
1659 | dm_table_put(map); | |
e61290a4 | 1660 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 1661 | |
cf222b37 | 1662 | return r; |
1da177e4 LT |
1663 | } |
1664 | ||
1665 | /*----------------------------------------------------------------- | |
1666 | * Event notification. | |
1667 | *---------------------------------------------------------------*/ | |
69267a30 AK |
1668 | void dm_kobject_uevent(struct mapped_device *md) |
1669 | { | |
ed9e1982 | 1670 | kobject_uevent(&disk_to_dev(md->disk)->kobj, KOBJ_CHANGE); |
69267a30 AK |
1671 | } |
1672 | ||
7a8c3d3b MA |
1673 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
1674 | { | |
1675 | return atomic_add_return(1, &md->uevent_seq); | |
1676 | } | |
1677 | ||
1da177e4 LT |
1678 | uint32_t dm_get_event_nr(struct mapped_device *md) |
1679 | { | |
1680 | return atomic_read(&md->event_nr); | |
1681 | } | |
1682 | ||
1683 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
1684 | { | |
1685 | return wait_event_interruptible(md->eventq, | |
1686 | (event_nr != atomic_read(&md->event_nr))); | |
1687 | } | |
1688 | ||
7a8c3d3b MA |
1689 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
1690 | { | |
1691 | unsigned long flags; | |
1692 | ||
1693 | spin_lock_irqsave(&md->uevent_lock, flags); | |
1694 | list_add(elist, &md->uevent_list); | |
1695 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
1696 | } | |
1697 | ||
1da177e4 LT |
1698 | /* |
1699 | * The gendisk is only valid as long as you have a reference | |
1700 | * count on 'md'. | |
1701 | */ | |
1702 | struct gendisk *dm_disk(struct mapped_device *md) | |
1703 | { | |
1704 | return md->disk; | |
1705 | } | |
1706 | ||
784aae73 MB |
1707 | struct kobject *dm_kobject(struct mapped_device *md) |
1708 | { | |
1709 | return &md->kobj; | |
1710 | } | |
1711 | ||
1712 | /* | |
1713 | * struct mapped_device should not be exported outside of dm.c | |
1714 | * so use this check to verify that kobj is part of md structure | |
1715 | */ | |
1716 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) | |
1717 | { | |
1718 | struct mapped_device *md; | |
1719 | ||
1720 | md = container_of(kobj, struct mapped_device, kobj); | |
1721 | if (&md->kobj != kobj) | |
1722 | return NULL; | |
1723 | ||
1724 | dm_get(md); | |
1725 | return md; | |
1726 | } | |
1727 | ||
1da177e4 LT |
1728 | int dm_suspended(struct mapped_device *md) |
1729 | { | |
1730 | return test_bit(DMF_SUSPENDED, &md->flags); | |
1731 | } | |
1732 | ||
2e93ccc1 KU |
1733 | int dm_noflush_suspending(struct dm_target *ti) |
1734 | { | |
1735 | struct mapped_device *md = dm_table_get_md(ti->table); | |
1736 | int r = __noflush_suspending(md); | |
1737 | ||
1738 | dm_put(md); | |
1739 | ||
1740 | return r; | |
1741 | } | |
1742 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
1743 | ||
1da177e4 LT |
1744 | static struct block_device_operations dm_blk_dops = { |
1745 | .open = dm_blk_open, | |
1746 | .release = dm_blk_close, | |
aa129a22 | 1747 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 1748 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
1749 | .owner = THIS_MODULE |
1750 | }; | |
1751 | ||
1752 | EXPORT_SYMBOL(dm_get_mapinfo); | |
1753 | ||
1754 | /* | |
1755 | * module hooks | |
1756 | */ | |
1757 | module_init(dm_init); | |
1758 | module_exit(dm_exit); | |
1759 | ||
1760 | module_param(major, uint, 0); | |
1761 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
1762 | MODULE_DESCRIPTION(DM_NAME " driver"); | |
1763 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
1764 | MODULE_LICENSE("GPL"); |