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Commit | Line | Data |
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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" | |
51e5b2bd | 9 | #include "dm-uevent.h" |
1da177e4 LT |
10 | |
11 | #include <linux/init.h> | |
12 | #include <linux/module.h> | |
48c9c27b | 13 | #include <linux/mutex.h> |
1da177e4 LT |
14 | #include <linux/moduleparam.h> |
15 | #include <linux/blkpg.h> | |
16 | #include <linux/bio.h> | |
17 | #include <linux/buffer_head.h> | |
18 | #include <linux/mempool.h> | |
19 | #include <linux/slab.h> | |
20 | #include <linux/idr.h> | |
3ac51e74 | 21 | #include <linux/hdreg.h> |
3f77316d | 22 | #include <linux/delay.h> |
55782138 LZ |
23 | |
24 | #include <trace/events/block.h> | |
1da177e4 | 25 | |
72d94861 AK |
26 | #define DM_MSG_PREFIX "core" |
27 | ||
60935eb2 MB |
28 | /* |
29 | * Cookies are numeric values sent with CHANGE and REMOVE | |
30 | * uevents while resuming, removing or renaming the device. | |
31 | */ | |
32 | #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" | |
33 | #define DM_COOKIE_LENGTH 24 | |
34 | ||
1da177e4 LT |
35 | static const char *_name = DM_NAME; |
36 | ||
37 | static unsigned int major = 0; | |
38 | static unsigned int _major = 0; | |
39 | ||
d15b774c AK |
40 | static DEFINE_IDR(_minor_idr); |
41 | ||
f32c10b0 | 42 | static DEFINE_SPINLOCK(_minor_lock); |
1da177e4 | 43 | /* |
8fbf26ad | 44 | * For bio-based dm. |
1da177e4 LT |
45 | * One of these is allocated per bio. |
46 | */ | |
47 | struct dm_io { | |
48 | struct mapped_device *md; | |
49 | int error; | |
1da177e4 | 50 | atomic_t io_count; |
6ae2fa67 | 51 | struct bio *bio; |
3eaf840e | 52 | unsigned long start_time; |
f88fb981 | 53 | spinlock_t endio_lock; |
1da177e4 LT |
54 | }; |
55 | ||
56 | /* | |
8fbf26ad | 57 | * For bio-based dm. |
1da177e4 LT |
58 | * One of these is allocated per target within a bio. Hopefully |
59 | * this will be simplified out one day. | |
60 | */ | |
028867ac | 61 | struct dm_target_io { |
1da177e4 LT |
62 | struct dm_io *io; |
63 | struct dm_target *ti; | |
64 | union map_info info; | |
65 | }; | |
66 | ||
8fbf26ad KU |
67 | /* |
68 | * For request-based dm. | |
69 | * One of these is allocated per request. | |
70 | */ | |
71 | struct dm_rq_target_io { | |
72 | struct mapped_device *md; | |
73 | struct dm_target *ti; | |
74 | struct request *orig, clone; | |
75 | int error; | |
76 | union map_info info; | |
77 | }; | |
78 | ||
79 | /* | |
80 | * For request-based dm. | |
81 | * One of these is allocated per bio. | |
82 | */ | |
83 | struct dm_rq_clone_bio_info { | |
84 | struct bio *orig; | |
cec47e3d | 85 | struct dm_rq_target_io *tio; |
8fbf26ad KU |
86 | }; |
87 | ||
1da177e4 LT |
88 | union map_info *dm_get_mapinfo(struct bio *bio) |
89 | { | |
17b2f66f | 90 | if (bio && bio->bi_private) |
028867ac | 91 | return &((struct dm_target_io *)bio->bi_private)->info; |
17b2f66f | 92 | return NULL; |
1da177e4 LT |
93 | } |
94 | ||
cec47e3d KU |
95 | union map_info *dm_get_rq_mapinfo(struct request *rq) |
96 | { | |
97 | if (rq && rq->end_io_data) | |
98 | return &((struct dm_rq_target_io *)rq->end_io_data)->info; | |
99 | return NULL; | |
100 | } | |
101 | EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo); | |
102 | ||
ba61fdd1 JM |
103 | #define MINOR_ALLOCED ((void *)-1) |
104 | ||
1da177e4 LT |
105 | /* |
106 | * Bits for the md->flags field. | |
107 | */ | |
1eb787ec | 108 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
1da177e4 | 109 | #define DMF_SUSPENDED 1 |
aa8d7c2f | 110 | #define DMF_FROZEN 2 |
fba9f90e | 111 | #define DMF_FREEING 3 |
5c6bd75d | 112 | #define DMF_DELETING 4 |
2e93ccc1 | 113 | #define DMF_NOFLUSH_SUSPENDING 5 |
d5b9dd04 | 114 | #define DMF_MERGE_IS_OPTIONAL 6 |
1da177e4 | 115 | |
304f3f6a MB |
116 | /* |
117 | * Work processed by per-device workqueue. | |
118 | */ | |
1da177e4 | 119 | struct mapped_device { |
2ca3310e | 120 | struct rw_semaphore io_lock; |
e61290a4 | 121 | struct mutex suspend_lock; |
1da177e4 LT |
122 | rwlock_t map_lock; |
123 | atomic_t holders; | |
5c6bd75d | 124 | atomic_t open_count; |
1da177e4 LT |
125 | |
126 | unsigned long flags; | |
127 | ||
165125e1 | 128 | struct request_queue *queue; |
a5664dad | 129 | unsigned type; |
4a0b4ddf | 130 | /* Protect queue and type against concurrent access. */ |
a5664dad MS |
131 | struct mutex type_lock; |
132 | ||
1da177e4 | 133 | struct gendisk *disk; |
7e51f257 | 134 | char name[16]; |
1da177e4 LT |
135 | |
136 | void *interface_ptr; | |
137 | ||
138 | /* | |
139 | * A list of ios that arrived while we were suspended. | |
140 | */ | |
316d315b | 141 | atomic_t pending[2]; |
1da177e4 | 142 | wait_queue_head_t wait; |
53d5914f | 143 | struct work_struct work; |
74859364 | 144 | struct bio_list deferred; |
022c2611 | 145 | spinlock_t deferred_lock; |
1da177e4 | 146 | |
af7e466a | 147 | /* |
29e4013d | 148 | * Processing queue (flush) |
304f3f6a MB |
149 | */ |
150 | struct workqueue_struct *wq; | |
151 | ||
1da177e4 LT |
152 | /* |
153 | * The current mapping. | |
154 | */ | |
155 | struct dm_table *map; | |
156 | ||
157 | /* | |
158 | * io objects are allocated from here. | |
159 | */ | |
160 | mempool_t *io_pool; | |
161 | mempool_t *tio_pool; | |
162 | ||
9faf400f SB |
163 | struct bio_set *bs; |
164 | ||
1da177e4 LT |
165 | /* |
166 | * Event handling. | |
167 | */ | |
168 | atomic_t event_nr; | |
169 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
170 | atomic_t uevent_seq; |
171 | struct list_head uevent_list; | |
172 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
173 | |
174 | /* | |
175 | * freeze/thaw support require holding onto a super block | |
176 | */ | |
177 | struct super_block *frozen_sb; | |
db8fef4f | 178 | struct block_device *bdev; |
3ac51e74 DW |
179 | |
180 | /* forced geometry settings */ | |
181 | struct hd_geometry geometry; | |
784aae73 | 182 | |
cec47e3d KU |
183 | /* For saving the address of __make_request for request based dm */ |
184 | make_request_fn *saved_make_request_fn; | |
185 | ||
784aae73 MB |
186 | /* sysfs handle */ |
187 | struct kobject kobj; | |
52b1fd5a | 188 | |
d87f4c14 TH |
189 | /* zero-length flush that will be cloned and submitted to targets */ |
190 | struct bio flush_bio; | |
1da177e4 LT |
191 | }; |
192 | ||
e6ee8c0b KU |
193 | /* |
194 | * For mempools pre-allocation at the table loading time. | |
195 | */ | |
196 | struct dm_md_mempools { | |
197 | mempool_t *io_pool; | |
198 | mempool_t *tio_pool; | |
199 | struct bio_set *bs; | |
200 | }; | |
201 | ||
1da177e4 | 202 | #define MIN_IOS 256 |
e18b890b CL |
203 | static struct kmem_cache *_io_cache; |
204 | static struct kmem_cache *_tio_cache; | |
8fbf26ad KU |
205 | static struct kmem_cache *_rq_tio_cache; |
206 | static struct kmem_cache *_rq_bio_info_cache; | |
1da177e4 | 207 | |
1da177e4 LT |
208 | static int __init local_init(void) |
209 | { | |
51157b4a | 210 | int r = -ENOMEM; |
1da177e4 | 211 | |
1da177e4 | 212 | /* allocate a slab for the dm_ios */ |
028867ac | 213 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 | 214 | if (!_io_cache) |
51157b4a | 215 | return r; |
1da177e4 LT |
216 | |
217 | /* allocate a slab for the target ios */ | |
028867ac | 218 | _tio_cache = KMEM_CACHE(dm_target_io, 0); |
51157b4a KU |
219 | if (!_tio_cache) |
220 | goto out_free_io_cache; | |
1da177e4 | 221 | |
8fbf26ad KU |
222 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
223 | if (!_rq_tio_cache) | |
224 | goto out_free_tio_cache; | |
225 | ||
226 | _rq_bio_info_cache = KMEM_CACHE(dm_rq_clone_bio_info, 0); | |
227 | if (!_rq_bio_info_cache) | |
228 | goto out_free_rq_tio_cache; | |
229 | ||
51e5b2bd | 230 | r = dm_uevent_init(); |
51157b4a | 231 | if (r) |
8fbf26ad | 232 | goto out_free_rq_bio_info_cache; |
51e5b2bd | 233 | |
1da177e4 LT |
234 | _major = major; |
235 | r = register_blkdev(_major, _name); | |
51157b4a KU |
236 | if (r < 0) |
237 | goto out_uevent_exit; | |
1da177e4 LT |
238 | |
239 | if (!_major) | |
240 | _major = r; | |
241 | ||
242 | return 0; | |
51157b4a KU |
243 | |
244 | out_uevent_exit: | |
245 | dm_uevent_exit(); | |
8fbf26ad KU |
246 | out_free_rq_bio_info_cache: |
247 | kmem_cache_destroy(_rq_bio_info_cache); | |
248 | out_free_rq_tio_cache: | |
249 | kmem_cache_destroy(_rq_tio_cache); | |
51157b4a KU |
250 | out_free_tio_cache: |
251 | kmem_cache_destroy(_tio_cache); | |
252 | out_free_io_cache: | |
253 | kmem_cache_destroy(_io_cache); | |
254 | ||
255 | return r; | |
1da177e4 LT |
256 | } |
257 | ||
258 | static void local_exit(void) | |
259 | { | |
8fbf26ad KU |
260 | kmem_cache_destroy(_rq_bio_info_cache); |
261 | kmem_cache_destroy(_rq_tio_cache); | |
1da177e4 LT |
262 | kmem_cache_destroy(_tio_cache); |
263 | kmem_cache_destroy(_io_cache); | |
00d59405 | 264 | unregister_blkdev(_major, _name); |
51e5b2bd | 265 | dm_uevent_exit(); |
1da177e4 LT |
266 | |
267 | _major = 0; | |
268 | ||
269 | DMINFO("cleaned up"); | |
270 | } | |
271 | ||
b9249e55 | 272 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
273 | local_init, |
274 | dm_target_init, | |
275 | dm_linear_init, | |
276 | dm_stripe_init, | |
952b3557 | 277 | dm_io_init, |
945fa4d2 | 278 | dm_kcopyd_init, |
1da177e4 LT |
279 | dm_interface_init, |
280 | }; | |
281 | ||
b9249e55 | 282 | static void (*_exits[])(void) = { |
1da177e4 LT |
283 | local_exit, |
284 | dm_target_exit, | |
285 | dm_linear_exit, | |
286 | dm_stripe_exit, | |
952b3557 | 287 | dm_io_exit, |
945fa4d2 | 288 | dm_kcopyd_exit, |
1da177e4 LT |
289 | dm_interface_exit, |
290 | }; | |
291 | ||
292 | static int __init dm_init(void) | |
293 | { | |
294 | const int count = ARRAY_SIZE(_inits); | |
295 | ||
296 | int r, i; | |
297 | ||
298 | for (i = 0; i < count; i++) { | |
299 | r = _inits[i](); | |
300 | if (r) | |
301 | goto bad; | |
302 | } | |
303 | ||
304 | return 0; | |
305 | ||
306 | bad: | |
307 | while (i--) | |
308 | _exits[i](); | |
309 | ||
310 | return r; | |
311 | } | |
312 | ||
313 | static void __exit dm_exit(void) | |
314 | { | |
315 | int i = ARRAY_SIZE(_exits); | |
316 | ||
317 | while (i--) | |
318 | _exits[i](); | |
d15b774c AK |
319 | |
320 | /* | |
321 | * Should be empty by this point. | |
322 | */ | |
323 | idr_remove_all(&_minor_idr); | |
324 | idr_destroy(&_minor_idr); | |
1da177e4 LT |
325 | } |
326 | ||
327 | /* | |
328 | * Block device functions | |
329 | */ | |
432a212c MA |
330 | int dm_deleting_md(struct mapped_device *md) |
331 | { | |
332 | return test_bit(DMF_DELETING, &md->flags); | |
333 | } | |
334 | ||
fe5f9f2c | 335 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
336 | { |
337 | struct mapped_device *md; | |
338 | ||
fba9f90e JM |
339 | spin_lock(&_minor_lock); |
340 | ||
fe5f9f2c | 341 | md = bdev->bd_disk->private_data; |
fba9f90e JM |
342 | if (!md) |
343 | goto out; | |
344 | ||
5c6bd75d | 345 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 346 | dm_deleting_md(md)) { |
fba9f90e JM |
347 | md = NULL; |
348 | goto out; | |
349 | } | |
350 | ||
1da177e4 | 351 | dm_get(md); |
5c6bd75d | 352 | atomic_inc(&md->open_count); |
fba9f90e JM |
353 | |
354 | out: | |
355 | spin_unlock(&_minor_lock); | |
356 | ||
357 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
358 | } |
359 | ||
fe5f9f2c | 360 | static int dm_blk_close(struct gendisk *disk, fmode_t mode) |
1da177e4 | 361 | { |
fe5f9f2c | 362 | struct mapped_device *md = disk->private_data; |
6e9624b8 | 363 | |
4a1aeb98 MB |
364 | spin_lock(&_minor_lock); |
365 | ||
5c6bd75d | 366 | atomic_dec(&md->open_count); |
1da177e4 | 367 | dm_put(md); |
4a1aeb98 MB |
368 | |
369 | spin_unlock(&_minor_lock); | |
6e9624b8 | 370 | |
1da177e4 LT |
371 | return 0; |
372 | } | |
373 | ||
5c6bd75d AK |
374 | int dm_open_count(struct mapped_device *md) |
375 | { | |
376 | return atomic_read(&md->open_count); | |
377 | } | |
378 | ||
379 | /* | |
380 | * Guarantees nothing is using the device before it's deleted. | |
381 | */ | |
382 | int dm_lock_for_deletion(struct mapped_device *md) | |
383 | { | |
384 | int r = 0; | |
385 | ||
386 | spin_lock(&_minor_lock); | |
387 | ||
388 | if (dm_open_count(md)) | |
389 | r = -EBUSY; | |
390 | else | |
391 | set_bit(DMF_DELETING, &md->flags); | |
392 | ||
393 | spin_unlock(&_minor_lock); | |
394 | ||
395 | return r; | |
396 | } | |
397 | ||
3ac51e74 DW |
398 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
399 | { | |
400 | struct mapped_device *md = bdev->bd_disk->private_data; | |
401 | ||
402 | return dm_get_geometry(md, geo); | |
403 | } | |
404 | ||
fe5f9f2c | 405 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
aa129a22 MB |
406 | unsigned int cmd, unsigned long arg) |
407 | { | |
fe5f9f2c | 408 | struct mapped_device *md = bdev->bd_disk->private_data; |
7c666411 | 409 | struct dm_table *map = dm_get_live_table(md); |
aa129a22 MB |
410 | struct dm_target *tgt; |
411 | int r = -ENOTTY; | |
412 | ||
aa129a22 MB |
413 | if (!map || !dm_table_get_size(map)) |
414 | goto out; | |
415 | ||
416 | /* We only support devices that have a single target */ | |
417 | if (dm_table_get_num_targets(map) != 1) | |
418 | goto out; | |
419 | ||
420 | tgt = dm_table_get_target(map, 0); | |
421 | ||
4f186f8b | 422 | if (dm_suspended_md(md)) { |
aa129a22 MB |
423 | r = -EAGAIN; |
424 | goto out; | |
425 | } | |
426 | ||
427 | if (tgt->type->ioctl) | |
647b3d00 | 428 | r = tgt->type->ioctl(tgt, cmd, arg); |
aa129a22 MB |
429 | |
430 | out: | |
431 | dm_table_put(map); | |
432 | ||
aa129a22 MB |
433 | return r; |
434 | } | |
435 | ||
028867ac | 436 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
437 | { |
438 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
439 | } | |
440 | ||
028867ac | 441 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
442 | { |
443 | mempool_free(io, md->io_pool); | |
444 | } | |
445 | ||
028867ac | 446 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 LT |
447 | { |
448 | mempool_free(tio, md->tio_pool); | |
449 | } | |
450 | ||
08885643 KU |
451 | static struct dm_rq_target_io *alloc_rq_tio(struct mapped_device *md, |
452 | gfp_t gfp_mask) | |
cec47e3d | 453 | { |
08885643 | 454 | return mempool_alloc(md->tio_pool, gfp_mask); |
cec47e3d KU |
455 | } |
456 | ||
457 | static void free_rq_tio(struct dm_rq_target_io *tio) | |
458 | { | |
459 | mempool_free(tio, tio->md->tio_pool); | |
460 | } | |
461 | ||
462 | static struct dm_rq_clone_bio_info *alloc_bio_info(struct mapped_device *md) | |
463 | { | |
464 | return mempool_alloc(md->io_pool, GFP_ATOMIC); | |
465 | } | |
466 | ||
467 | static void free_bio_info(struct dm_rq_clone_bio_info *info) | |
468 | { | |
469 | mempool_free(info, info->tio->md->io_pool); | |
470 | } | |
471 | ||
90abb8c4 KU |
472 | static int md_in_flight(struct mapped_device *md) |
473 | { | |
474 | return atomic_read(&md->pending[READ]) + | |
475 | atomic_read(&md->pending[WRITE]); | |
476 | } | |
477 | ||
3eaf840e JNN |
478 | static void start_io_acct(struct dm_io *io) |
479 | { | |
480 | struct mapped_device *md = io->md; | |
c9959059 | 481 | int cpu; |
316d315b | 482 | int rw = bio_data_dir(io->bio); |
3eaf840e JNN |
483 | |
484 | io->start_time = jiffies; | |
485 | ||
074a7aca TH |
486 | cpu = part_stat_lock(); |
487 | part_round_stats(cpu, &dm_disk(md)->part0); | |
488 | part_stat_unlock(); | |
1e9bb880 SL |
489 | atomic_set(&dm_disk(md)->part0.in_flight[rw], |
490 | atomic_inc_return(&md->pending[rw])); | |
3eaf840e JNN |
491 | } |
492 | ||
d221d2e7 | 493 | static void end_io_acct(struct dm_io *io) |
3eaf840e JNN |
494 | { |
495 | struct mapped_device *md = io->md; | |
496 | struct bio *bio = io->bio; | |
497 | unsigned long duration = jiffies - io->start_time; | |
c9959059 | 498 | int pending, cpu; |
3eaf840e JNN |
499 | int rw = bio_data_dir(bio); |
500 | ||
074a7aca TH |
501 | cpu = part_stat_lock(); |
502 | part_round_stats(cpu, &dm_disk(md)->part0); | |
503 | part_stat_add(cpu, &dm_disk(md)->part0, ticks[rw], duration); | |
504 | part_stat_unlock(); | |
3eaf840e | 505 | |
af7e466a MP |
506 | /* |
507 | * After this is decremented the bio must not be touched if it is | |
d87f4c14 | 508 | * a flush. |
af7e466a | 509 | */ |
1e9bb880 SL |
510 | pending = atomic_dec_return(&md->pending[rw]); |
511 | atomic_set(&dm_disk(md)->part0.in_flight[rw], pending); | |
316d315b | 512 | pending += atomic_read(&md->pending[rw^0x1]); |
3eaf840e | 513 | |
d221d2e7 MP |
514 | /* nudge anyone waiting on suspend queue */ |
515 | if (!pending) | |
516 | wake_up(&md->wait); | |
3eaf840e JNN |
517 | } |
518 | ||
1da177e4 LT |
519 | /* |
520 | * Add the bio to the list of deferred io. | |
521 | */ | |
92c63902 | 522 | static void queue_io(struct mapped_device *md, struct bio *bio) |
1da177e4 | 523 | { |
05447420 | 524 | unsigned long flags; |
1da177e4 | 525 | |
05447420 | 526 | spin_lock_irqsave(&md->deferred_lock, flags); |
1da177e4 | 527 | bio_list_add(&md->deferred, bio); |
05447420 | 528 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
6a8736d1 | 529 | queue_work(md->wq, &md->work); |
1da177e4 LT |
530 | } |
531 | ||
532 | /* | |
533 | * Everyone (including functions in this file), should use this | |
534 | * function to access the md->map field, and make sure they call | |
535 | * dm_table_put() when finished. | |
536 | */ | |
7c666411 | 537 | struct dm_table *dm_get_live_table(struct mapped_device *md) |
1da177e4 LT |
538 | { |
539 | struct dm_table *t; | |
523d9297 | 540 | unsigned long flags; |
1da177e4 | 541 | |
523d9297 | 542 | read_lock_irqsave(&md->map_lock, flags); |
1da177e4 LT |
543 | t = md->map; |
544 | if (t) | |
545 | dm_table_get(t); | |
523d9297 | 546 | read_unlock_irqrestore(&md->map_lock, flags); |
1da177e4 LT |
547 | |
548 | return t; | |
549 | } | |
550 | ||
3ac51e74 DW |
551 | /* |
552 | * Get the geometry associated with a dm device | |
553 | */ | |
554 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
555 | { | |
556 | *geo = md->geometry; | |
557 | ||
558 | return 0; | |
559 | } | |
560 | ||
561 | /* | |
562 | * Set the geometry of a device. | |
563 | */ | |
564 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
565 | { | |
566 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
567 | ||
568 | if (geo->start > sz) { | |
569 | DMWARN("Start sector is beyond the geometry limits."); | |
570 | return -EINVAL; | |
571 | } | |
572 | ||
573 | md->geometry = *geo; | |
574 | ||
575 | return 0; | |
576 | } | |
577 | ||
1da177e4 LT |
578 | /*----------------------------------------------------------------- |
579 | * CRUD START: | |
580 | * A more elegant soln is in the works that uses the queue | |
581 | * merge fn, unfortunately there are a couple of changes to | |
582 | * the block layer that I want to make for this. So in the | |
583 | * interests of getting something for people to use I give | |
584 | * you this clearly demarcated crap. | |
585 | *---------------------------------------------------------------*/ | |
586 | ||
2e93ccc1 KU |
587 | static int __noflush_suspending(struct mapped_device *md) |
588 | { | |
589 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
590 | } | |
591 | ||
1da177e4 LT |
592 | /* |
593 | * Decrements the number of outstanding ios that a bio has been | |
594 | * cloned into, completing the original io if necc. | |
595 | */ | |
858119e1 | 596 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 597 | { |
2e93ccc1 | 598 | unsigned long flags; |
b35f8caa MB |
599 | int io_error; |
600 | struct bio *bio; | |
601 | struct mapped_device *md = io->md; | |
2e93ccc1 KU |
602 | |
603 | /* Push-back supersedes any I/O errors */ | |
f88fb981 KU |
604 | if (unlikely(error)) { |
605 | spin_lock_irqsave(&io->endio_lock, flags); | |
606 | if (!(io->error > 0 && __noflush_suspending(md))) | |
607 | io->error = error; | |
608 | spin_unlock_irqrestore(&io->endio_lock, flags); | |
609 | } | |
1da177e4 LT |
610 | |
611 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
612 | if (io->error == DM_ENDIO_REQUEUE) { |
613 | /* | |
614 | * Target requested pushing back the I/O. | |
2e93ccc1 | 615 | */ |
022c2611 | 616 | spin_lock_irqsave(&md->deferred_lock, flags); |
6a8736d1 TH |
617 | if (__noflush_suspending(md)) |
618 | bio_list_add_head(&md->deferred, io->bio); | |
619 | else | |
2e93ccc1 KU |
620 | /* noflush suspend was interrupted. */ |
621 | io->error = -EIO; | |
022c2611 | 622 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
2e93ccc1 KU |
623 | } |
624 | ||
b35f8caa MB |
625 | io_error = io->error; |
626 | bio = io->bio; | |
6a8736d1 TH |
627 | end_io_acct(io); |
628 | free_io(md, io); | |
629 | ||
630 | if (io_error == DM_ENDIO_REQUEUE) | |
631 | return; | |
2e93ccc1 | 632 | |
b372d360 | 633 | if ((bio->bi_rw & REQ_FLUSH) && bio->bi_size) { |
af7e466a | 634 | /* |
6a8736d1 TH |
635 | * Preflush done for flush with data, reissue |
636 | * without REQ_FLUSH. | |
af7e466a | 637 | */ |
6a8736d1 TH |
638 | bio->bi_rw &= ~REQ_FLUSH; |
639 | queue_io(md, bio); | |
af7e466a | 640 | } else { |
b372d360 | 641 | /* done with normal IO or empty flush */ |
b7908c10 | 642 | trace_block_bio_complete(md->queue, bio, io_error); |
b372d360 | 643 | bio_endio(bio, io_error); |
b35f8caa | 644 | } |
1da177e4 LT |
645 | } |
646 | } | |
647 | ||
6712ecf8 | 648 | static void clone_endio(struct bio *bio, int error) |
1da177e4 LT |
649 | { |
650 | int r = 0; | |
028867ac | 651 | struct dm_target_io *tio = bio->bi_private; |
b35f8caa | 652 | struct dm_io *io = tio->io; |
9faf400f | 653 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
654 | dm_endio_fn endio = tio->ti->type->end_io; |
655 | ||
1da177e4 LT |
656 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
657 | error = -EIO; | |
658 | ||
659 | if (endio) { | |
660 | r = endio(tio->ti, bio, error, &tio->info); | |
2e93ccc1 KU |
661 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
662 | /* | |
663 | * error and requeue request are handled | |
664 | * in dec_pending(). | |
665 | */ | |
1da177e4 | 666 | error = r; |
45cbcd79 KU |
667 | else if (r == DM_ENDIO_INCOMPLETE) |
668 | /* The target will handle the io */ | |
6712ecf8 | 669 | return; |
45cbcd79 KU |
670 | else if (r) { |
671 | DMWARN("unimplemented target endio return value: %d", r); | |
672 | BUG(); | |
673 | } | |
1da177e4 LT |
674 | } |
675 | ||
9faf400f SB |
676 | /* |
677 | * Store md for cleanup instead of tio which is about to get freed. | |
678 | */ | |
679 | bio->bi_private = md->bs; | |
680 | ||
9faf400f | 681 | free_tio(md, tio); |
b35f8caa MB |
682 | bio_put(bio); |
683 | dec_pending(io, error); | |
1da177e4 LT |
684 | } |
685 | ||
cec47e3d KU |
686 | /* |
687 | * Partial completion handling for request-based dm | |
688 | */ | |
689 | static void end_clone_bio(struct bio *clone, int error) | |
690 | { | |
691 | struct dm_rq_clone_bio_info *info = clone->bi_private; | |
692 | struct dm_rq_target_io *tio = info->tio; | |
693 | struct bio *bio = info->orig; | |
694 | unsigned int nr_bytes = info->orig->bi_size; | |
695 | ||
696 | bio_put(clone); | |
697 | ||
698 | if (tio->error) | |
699 | /* | |
700 | * An error has already been detected on the request. | |
701 | * Once error occurred, just let clone->end_io() handle | |
702 | * the remainder. | |
703 | */ | |
704 | return; | |
705 | else if (error) { | |
706 | /* | |
707 | * Don't notice the error to the upper layer yet. | |
708 | * The error handling decision is made by the target driver, | |
709 | * when the request is completed. | |
710 | */ | |
711 | tio->error = error; | |
712 | return; | |
713 | } | |
714 | ||
715 | /* | |
716 | * I/O for the bio successfully completed. | |
717 | * Notice the data completion to the upper layer. | |
718 | */ | |
719 | ||
720 | /* | |
721 | * bios are processed from the head of the list. | |
722 | * So the completing bio should always be rq->bio. | |
723 | * If it's not, something wrong is happening. | |
724 | */ | |
725 | if (tio->orig->bio != bio) | |
726 | DMERR("bio completion is going in the middle of the request"); | |
727 | ||
728 | /* | |
729 | * Update the original request. | |
730 | * Do not use blk_end_request() here, because it may complete | |
731 | * the original request before the clone, and break the ordering. | |
732 | */ | |
733 | blk_update_request(tio->orig, 0, nr_bytes); | |
734 | } | |
735 | ||
736 | /* | |
737 | * Don't touch any member of the md after calling this function because | |
738 | * the md may be freed in dm_put() at the end of this function. | |
739 | * Or do dm_get() before calling this function and dm_put() later. | |
740 | */ | |
b4324fee | 741 | static void rq_completed(struct mapped_device *md, int rw, int run_queue) |
cec47e3d | 742 | { |
b4324fee | 743 | atomic_dec(&md->pending[rw]); |
cec47e3d KU |
744 | |
745 | /* nudge anyone waiting on suspend queue */ | |
b4324fee | 746 | if (!md_in_flight(md)) |
cec47e3d KU |
747 | wake_up(&md->wait); |
748 | ||
749 | if (run_queue) | |
b4324fee | 750 | blk_run_queue(md->queue); |
cec47e3d KU |
751 | |
752 | /* | |
753 | * dm_put() must be at the end of this function. See the comment above | |
754 | */ | |
755 | dm_put(md); | |
756 | } | |
757 | ||
a77e28c7 KU |
758 | static void free_rq_clone(struct request *clone) |
759 | { | |
760 | struct dm_rq_target_io *tio = clone->end_io_data; | |
761 | ||
762 | blk_rq_unprep_clone(clone); | |
763 | free_rq_tio(tio); | |
764 | } | |
765 | ||
980691e5 KU |
766 | /* |
767 | * Complete the clone and the original request. | |
768 | * Must be called without queue lock. | |
769 | */ | |
770 | static void dm_end_request(struct request *clone, int error) | |
771 | { | |
772 | int rw = rq_data_dir(clone); | |
773 | struct dm_rq_target_io *tio = clone->end_io_data; | |
774 | struct mapped_device *md = tio->md; | |
775 | struct request *rq = tio->orig; | |
776 | ||
29e4013d | 777 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
980691e5 KU |
778 | rq->errors = clone->errors; |
779 | rq->resid_len = clone->resid_len; | |
780 | ||
781 | if (rq->sense) | |
782 | /* | |
783 | * We are using the sense buffer of the original | |
784 | * request. | |
785 | * So setting the length of the sense data is enough. | |
786 | */ | |
787 | rq->sense_len = clone->sense_len; | |
788 | } | |
789 | ||
790 | free_rq_clone(clone); | |
29e4013d TH |
791 | blk_end_request_all(rq, error); |
792 | rq_completed(md, rw, true); | |
980691e5 KU |
793 | } |
794 | ||
cec47e3d KU |
795 | static void dm_unprep_request(struct request *rq) |
796 | { | |
797 | struct request *clone = rq->special; | |
cec47e3d KU |
798 | |
799 | rq->special = NULL; | |
800 | rq->cmd_flags &= ~REQ_DONTPREP; | |
801 | ||
a77e28c7 | 802 | free_rq_clone(clone); |
cec47e3d KU |
803 | } |
804 | ||
805 | /* | |
806 | * Requeue the original request of a clone. | |
807 | */ | |
808 | void dm_requeue_unmapped_request(struct request *clone) | |
809 | { | |
b4324fee | 810 | int rw = rq_data_dir(clone); |
cec47e3d KU |
811 | struct dm_rq_target_io *tio = clone->end_io_data; |
812 | struct mapped_device *md = tio->md; | |
813 | struct request *rq = tio->orig; | |
814 | struct request_queue *q = rq->q; | |
815 | unsigned long flags; | |
816 | ||
817 | dm_unprep_request(rq); | |
818 | ||
819 | spin_lock_irqsave(q->queue_lock, flags); | |
cec47e3d KU |
820 | blk_requeue_request(q, rq); |
821 | spin_unlock_irqrestore(q->queue_lock, flags); | |
822 | ||
b4324fee | 823 | rq_completed(md, rw, 0); |
cec47e3d KU |
824 | } |
825 | EXPORT_SYMBOL_GPL(dm_requeue_unmapped_request); | |
826 | ||
827 | static void __stop_queue(struct request_queue *q) | |
828 | { | |
829 | blk_stop_queue(q); | |
830 | } | |
831 | ||
832 | static void stop_queue(struct request_queue *q) | |
833 | { | |
834 | unsigned long flags; | |
835 | ||
836 | spin_lock_irqsave(q->queue_lock, flags); | |
837 | __stop_queue(q); | |
838 | spin_unlock_irqrestore(q->queue_lock, flags); | |
839 | } | |
840 | ||
841 | static void __start_queue(struct request_queue *q) | |
842 | { | |
843 | if (blk_queue_stopped(q)) | |
844 | blk_start_queue(q); | |
845 | } | |
846 | ||
847 | static void start_queue(struct request_queue *q) | |
848 | { | |
849 | unsigned long flags; | |
850 | ||
851 | spin_lock_irqsave(q->queue_lock, flags); | |
852 | __start_queue(q); | |
853 | spin_unlock_irqrestore(q->queue_lock, flags); | |
854 | } | |
855 | ||
11a68244 | 856 | static void dm_done(struct request *clone, int error, bool mapped) |
cec47e3d | 857 | { |
11a68244 | 858 | int r = error; |
cec47e3d KU |
859 | struct dm_rq_target_io *tio = clone->end_io_data; |
860 | dm_request_endio_fn rq_end_io = tio->ti->type->rq_end_io; | |
cec47e3d | 861 | |
11a68244 KU |
862 | if (mapped && rq_end_io) |
863 | r = rq_end_io(tio->ti, clone, error, &tio->info); | |
cec47e3d | 864 | |
11a68244 | 865 | if (r <= 0) |
cec47e3d | 866 | /* The target wants to complete the I/O */ |
11a68244 KU |
867 | dm_end_request(clone, r); |
868 | else if (r == DM_ENDIO_INCOMPLETE) | |
cec47e3d KU |
869 | /* The target will handle the I/O */ |
870 | return; | |
11a68244 | 871 | else if (r == DM_ENDIO_REQUEUE) |
cec47e3d KU |
872 | /* The target wants to requeue the I/O */ |
873 | dm_requeue_unmapped_request(clone); | |
874 | else { | |
11a68244 | 875 | DMWARN("unimplemented target endio return value: %d", r); |
cec47e3d KU |
876 | BUG(); |
877 | } | |
878 | } | |
879 | ||
11a68244 KU |
880 | /* |
881 | * Request completion handler for request-based dm | |
882 | */ | |
883 | static void dm_softirq_done(struct request *rq) | |
884 | { | |
885 | bool mapped = true; | |
886 | struct request *clone = rq->completion_data; | |
887 | struct dm_rq_target_io *tio = clone->end_io_data; | |
888 | ||
889 | if (rq->cmd_flags & REQ_FAILED) | |
890 | mapped = false; | |
891 | ||
892 | dm_done(clone, tio->error, mapped); | |
893 | } | |
894 | ||
cec47e3d KU |
895 | /* |
896 | * Complete the clone and the original request with the error status | |
897 | * through softirq context. | |
898 | */ | |
899 | static void dm_complete_request(struct request *clone, int error) | |
900 | { | |
901 | struct dm_rq_target_io *tio = clone->end_io_data; | |
902 | struct request *rq = tio->orig; | |
903 | ||
904 | tio->error = error; | |
905 | rq->completion_data = clone; | |
906 | blk_complete_request(rq); | |
907 | } | |
908 | ||
909 | /* | |
910 | * Complete the not-mapped clone and the original request with the error status | |
911 | * through softirq context. | |
912 | * Target's rq_end_io() function isn't called. | |
913 | * This may be used when the target's map_rq() function fails. | |
914 | */ | |
915 | void dm_kill_unmapped_request(struct request *clone, int error) | |
916 | { | |
917 | struct dm_rq_target_io *tio = clone->end_io_data; | |
918 | struct request *rq = tio->orig; | |
919 | ||
920 | rq->cmd_flags |= REQ_FAILED; | |
921 | dm_complete_request(clone, error); | |
922 | } | |
923 | EXPORT_SYMBOL_GPL(dm_kill_unmapped_request); | |
924 | ||
925 | /* | |
926 | * Called with the queue lock held | |
927 | */ | |
928 | static void end_clone_request(struct request *clone, int error) | |
929 | { | |
930 | /* | |
931 | * For just cleaning up the information of the queue in which | |
932 | * the clone was dispatched. | |
933 | * The clone is *NOT* freed actually here because it is alloced from | |
934 | * dm own mempool and REQ_ALLOCED isn't set in clone->cmd_flags. | |
935 | */ | |
936 | __blk_put_request(clone->q, clone); | |
937 | ||
938 | /* | |
939 | * Actual request completion is done in a softirq context which doesn't | |
940 | * hold the queue lock. Otherwise, deadlock could occur because: | |
941 | * - another request may be submitted by the upper level driver | |
942 | * of the stacking during the completion | |
943 | * - the submission which requires queue lock may be done | |
944 | * against this queue | |
945 | */ | |
946 | dm_complete_request(clone, error); | |
947 | } | |
948 | ||
56a67df7 MS |
949 | /* |
950 | * Return maximum size of I/O possible at the supplied sector up to the current | |
951 | * target boundary. | |
952 | */ | |
953 | static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti) | |
954 | { | |
955 | sector_t target_offset = dm_target_offset(ti, sector); | |
956 | ||
957 | return ti->len - target_offset; | |
958 | } | |
959 | ||
960 | static sector_t max_io_len(sector_t sector, struct dm_target *ti) | |
1da177e4 | 961 | { |
56a67df7 | 962 | sector_t len = max_io_len_target_boundary(sector, ti); |
1da177e4 LT |
963 | |
964 | /* | |
965 | * Does the target need to split even further ? | |
966 | */ | |
967 | if (ti->split_io) { | |
968 | sector_t boundary; | |
56a67df7 | 969 | sector_t offset = dm_target_offset(ti, sector); |
1da177e4 LT |
970 | boundary = ((offset + ti->split_io) & ~(ti->split_io - 1)) |
971 | - offset; | |
972 | if (len > boundary) | |
973 | len = boundary; | |
974 | } | |
975 | ||
976 | return len; | |
977 | } | |
978 | ||
979 | static void __map_bio(struct dm_target *ti, struct bio *clone, | |
028867ac | 980 | struct dm_target_io *tio) |
1da177e4 LT |
981 | { |
982 | int r; | |
2056a782 | 983 | sector_t sector; |
9faf400f | 984 | struct mapped_device *md; |
1da177e4 | 985 | |
1da177e4 LT |
986 | clone->bi_end_io = clone_endio; |
987 | clone->bi_private = tio; | |
988 | ||
989 | /* | |
990 | * Map the clone. If r == 0 we don't need to do | |
991 | * anything, the target has assumed ownership of | |
992 | * this io. | |
993 | */ | |
994 | atomic_inc(&tio->io->io_count); | |
2056a782 | 995 | sector = clone->bi_sector; |
1da177e4 | 996 | r = ti->type->map(ti, clone, &tio->info); |
45cbcd79 | 997 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 998 | /* the bio has been remapped so dispatch it */ |
2056a782 | 999 | |
d07335e5 MS |
1000 | trace_block_bio_remap(bdev_get_queue(clone->bi_bdev), clone, |
1001 | tio->io->bio->bi_bdev->bd_dev, sector); | |
2056a782 | 1002 | |
1da177e4 | 1003 | generic_make_request(clone); |
2e93ccc1 KU |
1004 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
1005 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
1006 | md = tio->io->md; |
1007 | dec_pending(tio->io, r); | |
1008 | /* | |
1009 | * Store bio_set for cleanup. | |
1010 | */ | |
1011 | clone->bi_private = md->bs; | |
1da177e4 | 1012 | bio_put(clone); |
9faf400f | 1013 | free_tio(md, tio); |
45cbcd79 KU |
1014 | } else if (r) { |
1015 | DMWARN("unimplemented target map return value: %d", r); | |
1016 | BUG(); | |
1da177e4 LT |
1017 | } |
1018 | } | |
1019 | ||
1020 | struct clone_info { | |
1021 | struct mapped_device *md; | |
1022 | struct dm_table *map; | |
1023 | struct bio *bio; | |
1024 | struct dm_io *io; | |
1025 | sector_t sector; | |
1026 | sector_t sector_count; | |
1027 | unsigned short idx; | |
1028 | }; | |
1029 | ||
3676347a PO |
1030 | static void dm_bio_destructor(struct bio *bio) |
1031 | { | |
9faf400f SB |
1032 | struct bio_set *bs = bio->bi_private; |
1033 | ||
1034 | bio_free(bio, bs); | |
3676347a PO |
1035 | } |
1036 | ||
1da177e4 | 1037 | /* |
d87f4c14 | 1038 | * Creates a little bio that just does part of a bvec. |
1da177e4 LT |
1039 | */ |
1040 | static struct bio *split_bvec(struct bio *bio, sector_t sector, | |
1041 | unsigned short idx, unsigned int offset, | |
9faf400f | 1042 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
1043 | { |
1044 | struct bio *clone; | |
1045 | struct bio_vec *bv = bio->bi_io_vec + idx; | |
1046 | ||
9faf400f | 1047 | clone = bio_alloc_bioset(GFP_NOIO, 1, bs); |
3676347a | 1048 | clone->bi_destructor = dm_bio_destructor; |
1da177e4 LT |
1049 | *clone->bi_io_vec = *bv; |
1050 | ||
1051 | clone->bi_sector = sector; | |
1052 | clone->bi_bdev = bio->bi_bdev; | |
d87f4c14 | 1053 | clone->bi_rw = bio->bi_rw; |
1da177e4 LT |
1054 | clone->bi_vcnt = 1; |
1055 | clone->bi_size = to_bytes(len); | |
1056 | clone->bi_io_vec->bv_offset = offset; | |
1057 | clone->bi_io_vec->bv_len = clone->bi_size; | |
f3e1d26e | 1058 | clone->bi_flags |= 1 << BIO_CLONED; |
1da177e4 | 1059 | |
9c47008d | 1060 | if (bio_integrity(bio)) { |
7878cba9 | 1061 | bio_integrity_clone(clone, bio, GFP_NOIO, bs); |
9c47008d MP |
1062 | bio_integrity_trim(clone, |
1063 | bio_sector_offset(bio, idx, offset), len); | |
1064 | } | |
1065 | ||
1da177e4 LT |
1066 | return clone; |
1067 | } | |
1068 | ||
1069 | /* | |
1070 | * Creates a bio that consists of range of complete bvecs. | |
1071 | */ | |
1072 | static struct bio *clone_bio(struct bio *bio, sector_t sector, | |
1073 | unsigned short idx, unsigned short bv_count, | |
9faf400f | 1074 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
1075 | { |
1076 | struct bio *clone; | |
1077 | ||
9faf400f SB |
1078 | clone = bio_alloc_bioset(GFP_NOIO, bio->bi_max_vecs, bs); |
1079 | __bio_clone(clone, bio); | |
1080 | clone->bi_destructor = dm_bio_destructor; | |
1da177e4 LT |
1081 | clone->bi_sector = sector; |
1082 | clone->bi_idx = idx; | |
1083 | clone->bi_vcnt = idx + bv_count; | |
1084 | clone->bi_size = to_bytes(len); | |
1085 | clone->bi_flags &= ~(1 << BIO_SEG_VALID); | |
1086 | ||
9c47008d | 1087 | if (bio_integrity(bio)) { |
7878cba9 | 1088 | bio_integrity_clone(clone, bio, GFP_NOIO, bs); |
9c47008d MP |
1089 | |
1090 | if (idx != bio->bi_idx || clone->bi_size < bio->bi_size) | |
1091 | bio_integrity_trim(clone, | |
1092 | bio_sector_offset(bio, idx, 0), len); | |
1093 | } | |
1094 | ||
1da177e4 LT |
1095 | return clone; |
1096 | } | |
1097 | ||
9015df24 AK |
1098 | static struct dm_target_io *alloc_tio(struct clone_info *ci, |
1099 | struct dm_target *ti) | |
f9ab94ce | 1100 | { |
9015df24 | 1101 | struct dm_target_io *tio = mempool_alloc(ci->md->tio_pool, GFP_NOIO); |
f9ab94ce MP |
1102 | |
1103 | tio->io = ci->io; | |
1104 | tio->ti = ti; | |
f9ab94ce | 1105 | memset(&tio->info, 0, sizeof(tio->info)); |
9015df24 AK |
1106 | |
1107 | return tio; | |
1108 | } | |
1109 | ||
06a426ce | 1110 | static void __issue_target_request(struct clone_info *ci, struct dm_target *ti, |
a79245b3 | 1111 | unsigned request_nr, sector_t len) |
9015df24 AK |
1112 | { |
1113 | struct dm_target_io *tio = alloc_tio(ci, ti); | |
1114 | struct bio *clone; | |
1115 | ||
57cba5d3 | 1116 | tio->info.target_request_nr = request_nr; |
f9ab94ce | 1117 | |
06a426ce MS |
1118 | /* |
1119 | * Discard requests require the bio's inline iovecs be initialized. | |
1120 | * ci->bio->bi_max_vecs is BIO_INLINE_VECS anyway, for both flush | |
1121 | * and discard, so no need for concern about wasted bvec allocations. | |
1122 | */ | |
1123 | clone = bio_alloc_bioset(GFP_NOIO, ci->bio->bi_max_vecs, ci->md->bs); | |
f9ab94ce MP |
1124 | __bio_clone(clone, ci->bio); |
1125 | clone->bi_destructor = dm_bio_destructor; | |
a79245b3 MS |
1126 | if (len) { |
1127 | clone->bi_sector = ci->sector; | |
1128 | clone->bi_size = to_bytes(len); | |
1129 | } | |
f9ab94ce MP |
1130 | |
1131 | __map_bio(ti, clone, tio); | |
1132 | } | |
1133 | ||
06a426ce | 1134 | static void __issue_target_requests(struct clone_info *ci, struct dm_target *ti, |
a79245b3 | 1135 | unsigned num_requests, sector_t len) |
06a426ce MS |
1136 | { |
1137 | unsigned request_nr; | |
1138 | ||
1139 | for (request_nr = 0; request_nr < num_requests; request_nr++) | |
a79245b3 | 1140 | __issue_target_request(ci, ti, request_nr, len); |
06a426ce MS |
1141 | } |
1142 | ||
b372d360 | 1143 | static int __clone_and_map_empty_flush(struct clone_info *ci) |
f9ab94ce | 1144 | { |
06a426ce | 1145 | unsigned target_nr = 0; |
f9ab94ce MP |
1146 | struct dm_target *ti; |
1147 | ||
b372d360 | 1148 | BUG_ON(bio_has_data(ci->bio)); |
f9ab94ce | 1149 | while ((ti = dm_table_get_target(ci->map, target_nr++))) |
a79245b3 | 1150 | __issue_target_requests(ci, ti, ti->num_flush_requests, 0); |
f9ab94ce | 1151 | |
f9ab94ce MP |
1152 | return 0; |
1153 | } | |
1154 | ||
5ae89a87 MS |
1155 | /* |
1156 | * Perform all io with a single clone. | |
1157 | */ | |
1158 | static void __clone_and_map_simple(struct clone_info *ci, struct dm_target *ti) | |
1159 | { | |
1160 | struct bio *clone, *bio = ci->bio; | |
1161 | struct dm_target_io *tio; | |
1162 | ||
1163 | tio = alloc_tio(ci, ti); | |
1164 | clone = clone_bio(bio, ci->sector, ci->idx, | |
1165 | bio->bi_vcnt - ci->idx, ci->sector_count, | |
1166 | ci->md->bs); | |
1167 | __map_bio(ti, clone, tio); | |
1168 | ci->sector_count = 0; | |
1169 | } | |
1170 | ||
1171 | static int __clone_and_map_discard(struct clone_info *ci) | |
1172 | { | |
1173 | struct dm_target *ti; | |
a79245b3 | 1174 | sector_t len; |
5ae89a87 | 1175 | |
a79245b3 MS |
1176 | do { |
1177 | ti = dm_table_find_target(ci->map, ci->sector); | |
1178 | if (!dm_target_is_valid(ti)) | |
1179 | return -EIO; | |
5ae89a87 | 1180 | |
5ae89a87 | 1181 | /* |
a79245b3 | 1182 | * Even though the device advertised discard support, |
936688d7 MS |
1183 | * that does not mean every target supports it, and |
1184 | * reconfiguration might also have changed that since the | |
a79245b3 | 1185 | * check was performed. |
5ae89a87 | 1186 | */ |
a79245b3 MS |
1187 | if (!ti->num_discard_requests) |
1188 | return -EOPNOTSUPP; | |
5ae89a87 | 1189 | |
a79245b3 | 1190 | len = min(ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); |
06a426ce | 1191 | |
a79245b3 MS |
1192 | __issue_target_requests(ci, ti, ti->num_discard_requests, len); |
1193 | ||
1194 | ci->sector += len; | |
1195 | } while (ci->sector_count -= len); | |
5ae89a87 MS |
1196 | |
1197 | return 0; | |
1198 | } | |
1199 | ||
512875bd | 1200 | static int __clone_and_map(struct clone_info *ci) |
1da177e4 LT |
1201 | { |
1202 | struct bio *clone, *bio = ci->bio; | |
512875bd JN |
1203 | struct dm_target *ti; |
1204 | sector_t len = 0, max; | |
028867ac | 1205 | struct dm_target_io *tio; |
1da177e4 | 1206 | |
5ae89a87 MS |
1207 | if (unlikely(bio->bi_rw & REQ_DISCARD)) |
1208 | return __clone_and_map_discard(ci); | |
1209 | ||
512875bd JN |
1210 | ti = dm_table_find_target(ci->map, ci->sector); |
1211 | if (!dm_target_is_valid(ti)) | |
1212 | return -EIO; | |
1213 | ||
56a67df7 | 1214 | max = max_io_len(ci->sector, ti); |
512875bd | 1215 | |
1da177e4 LT |
1216 | if (ci->sector_count <= max) { |
1217 | /* | |
1218 | * Optimise for the simple case where we can do all of | |
1219 | * the remaining io with a single clone. | |
1220 | */ | |
5ae89a87 | 1221 | __clone_and_map_simple(ci, ti); |
1da177e4 LT |
1222 | |
1223 | } else if (to_sector(bio->bi_io_vec[ci->idx].bv_len) <= max) { | |
1224 | /* | |
1225 | * There are some bvecs that don't span targets. | |
1226 | * Do as many of these as possible. | |
1227 | */ | |
1228 | int i; | |
1229 | sector_t remaining = max; | |
1230 | sector_t bv_len; | |
1231 | ||
1232 | for (i = ci->idx; remaining && (i < bio->bi_vcnt); i++) { | |
1233 | bv_len = to_sector(bio->bi_io_vec[i].bv_len); | |
1234 | ||
1235 | if (bv_len > remaining) | |
1236 | break; | |
1237 | ||
1238 | remaining -= bv_len; | |
1239 | len += bv_len; | |
1240 | } | |
1241 | ||
5ae89a87 | 1242 | tio = alloc_tio(ci, ti); |
9faf400f SB |
1243 | clone = clone_bio(bio, ci->sector, ci->idx, i - ci->idx, len, |
1244 | ci->md->bs); | |
1da177e4 LT |
1245 | __map_bio(ti, clone, tio); |
1246 | ||
1247 | ci->sector += len; | |
1248 | ci->sector_count -= len; | |
1249 | ci->idx = i; | |
1250 | ||
1251 | } else { | |
1252 | /* | |
d2044a94 | 1253 | * Handle a bvec that must be split between two or more targets. |
1da177e4 LT |
1254 | */ |
1255 | struct bio_vec *bv = bio->bi_io_vec + ci->idx; | |
d2044a94 AK |
1256 | sector_t remaining = to_sector(bv->bv_len); |
1257 | unsigned int offset = 0; | |
1da177e4 | 1258 | |
d2044a94 AK |
1259 | do { |
1260 | if (offset) { | |
1261 | ti = dm_table_find_target(ci->map, ci->sector); | |
512875bd JN |
1262 | if (!dm_target_is_valid(ti)) |
1263 | return -EIO; | |
1264 | ||
56a67df7 | 1265 | max = max_io_len(ci->sector, ti); |
d2044a94 AK |
1266 | } |
1267 | ||
1268 | len = min(remaining, max); | |
1269 | ||
5ae89a87 | 1270 | tio = alloc_tio(ci, ti); |
d2044a94 | 1271 | clone = split_bvec(bio, ci->sector, ci->idx, |
9faf400f SB |
1272 | bv->bv_offset + offset, len, |
1273 | ci->md->bs); | |
d2044a94 AK |
1274 | |
1275 | __map_bio(ti, clone, tio); | |
1276 | ||
1277 | ci->sector += len; | |
1278 | ci->sector_count -= len; | |
1279 | offset += to_bytes(len); | |
1280 | } while (remaining -= len); | |
1da177e4 | 1281 | |
1da177e4 LT |
1282 | ci->idx++; |
1283 | } | |
512875bd JN |
1284 | |
1285 | return 0; | |
1da177e4 LT |
1286 | } |
1287 | ||
1288 | /* | |
8a53c28d | 1289 | * Split the bio into several clones and submit it to targets. |
1da177e4 | 1290 | */ |
f0b9a450 | 1291 | static void __split_and_process_bio(struct mapped_device *md, struct bio *bio) |
1da177e4 LT |
1292 | { |
1293 | struct clone_info ci; | |
512875bd | 1294 | int error = 0; |
1da177e4 | 1295 | |
7c666411 | 1296 | ci.map = dm_get_live_table(md); |
f0b9a450 | 1297 | if (unlikely(!ci.map)) { |
6a8736d1 | 1298 | bio_io_error(bio); |
f0b9a450 MP |
1299 | return; |
1300 | } | |
692d0eb9 | 1301 | |
1da177e4 | 1302 | ci.md = md; |
1da177e4 LT |
1303 | ci.io = alloc_io(md); |
1304 | ci.io->error = 0; | |
1305 | atomic_set(&ci.io->io_count, 1); | |
1306 | ci.io->bio = bio; | |
1307 | ci.io->md = md; | |
f88fb981 | 1308 | spin_lock_init(&ci.io->endio_lock); |
1da177e4 | 1309 | ci.sector = bio->bi_sector; |
1da177e4 LT |
1310 | ci.idx = bio->bi_idx; |
1311 | ||
3eaf840e | 1312 | start_io_acct(ci.io); |
b372d360 MS |
1313 | if (bio->bi_rw & REQ_FLUSH) { |
1314 | ci.bio = &ci.md->flush_bio; | |
1315 | ci.sector_count = 0; | |
1316 | error = __clone_and_map_empty_flush(&ci); | |
1317 | /* dec_pending submits any data associated with flush */ | |
1318 | } else { | |
6a8736d1 | 1319 | ci.bio = bio; |
d87f4c14 | 1320 | ci.sector_count = bio_sectors(bio); |
b372d360 | 1321 | while (ci.sector_count && !error) |
d87f4c14 | 1322 | error = __clone_and_map(&ci); |
d87f4c14 | 1323 | } |
1da177e4 LT |
1324 | |
1325 | /* drop the extra reference count */ | |
512875bd | 1326 | dec_pending(ci.io, error); |
1da177e4 LT |
1327 | dm_table_put(ci.map); |
1328 | } | |
1329 | /*----------------------------------------------------------------- | |
1330 | * CRUD END | |
1331 | *---------------------------------------------------------------*/ | |
1332 | ||
f6fccb12 MB |
1333 | static int dm_merge_bvec(struct request_queue *q, |
1334 | struct bvec_merge_data *bvm, | |
1335 | struct bio_vec *biovec) | |
1336 | { | |
1337 | struct mapped_device *md = q->queuedata; | |
7c666411 | 1338 | struct dm_table *map = dm_get_live_table(md); |
f6fccb12 MB |
1339 | struct dm_target *ti; |
1340 | sector_t max_sectors; | |
5037108a | 1341 | int max_size = 0; |
f6fccb12 MB |
1342 | |
1343 | if (unlikely(!map)) | |
5037108a | 1344 | goto out; |
f6fccb12 MB |
1345 | |
1346 | ti = dm_table_find_target(map, bvm->bi_sector); | |
b01cd5ac MP |
1347 | if (!dm_target_is_valid(ti)) |
1348 | goto out_table; | |
f6fccb12 MB |
1349 | |
1350 | /* | |
1351 | * Find maximum amount of I/O that won't need splitting | |
1352 | */ | |
56a67df7 | 1353 | max_sectors = min(max_io_len(bvm->bi_sector, ti), |
f6fccb12 MB |
1354 | (sector_t) BIO_MAX_SECTORS); |
1355 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; | |
1356 | if (max_size < 0) | |
1357 | max_size = 0; | |
1358 | ||
1359 | /* | |
1360 | * merge_bvec_fn() returns number of bytes | |
1361 | * it can accept at this offset | |
1362 | * max is precomputed maximal io size | |
1363 | */ | |
1364 | if (max_size && ti->type->merge) | |
1365 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
8cbeb67a MP |
1366 | /* |
1367 | * If the target doesn't support merge method and some of the devices | |
1368 | * provided their merge_bvec method (we know this by looking at | |
1369 | * queue_max_hw_sectors), then we can't allow bios with multiple vector | |
1370 | * entries. So always set max_size to 0, and the code below allows | |
1371 | * just one page. | |
1372 | */ | |
1373 | else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9) | |
1374 | ||
1375 | max_size = 0; | |
f6fccb12 | 1376 | |
b01cd5ac | 1377 | out_table: |
5037108a MP |
1378 | dm_table_put(map); |
1379 | ||
1380 | out: | |
f6fccb12 MB |
1381 | /* |
1382 | * Always allow an entire first page | |
1383 | */ | |
1384 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
1385 | max_size = biovec->bv_len; | |
1386 | ||
f6fccb12 MB |
1387 | return max_size; |
1388 | } | |
1389 | ||
1da177e4 LT |
1390 | /* |
1391 | * The request function that just remaps the bio built up by | |
1392 | * dm_merge_bvec. | |
1393 | */ | |
cec47e3d | 1394 | static int _dm_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 1395 | { |
12f03a49 | 1396 | int rw = bio_data_dir(bio); |
1da177e4 | 1397 | struct mapped_device *md = q->queuedata; |
c9959059 | 1398 | int cpu; |
1da177e4 | 1399 | |
2ca3310e | 1400 | down_read(&md->io_lock); |
1da177e4 | 1401 | |
074a7aca TH |
1402 | cpu = part_stat_lock(); |
1403 | part_stat_inc(cpu, &dm_disk(md)->part0, ios[rw]); | |
1404 | part_stat_add(cpu, &dm_disk(md)->part0, sectors[rw], bio_sectors(bio)); | |
1405 | part_stat_unlock(); | |
12f03a49 | 1406 | |
6a8736d1 TH |
1407 | /* if we're suspended, we have to queue this io for later */ |
1408 | if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { | |
2ca3310e | 1409 | up_read(&md->io_lock); |
1da177e4 | 1410 | |
6a8736d1 TH |
1411 | if (bio_rw(bio) != READA) |
1412 | queue_io(md, bio); | |
1413 | else | |
54d9a1b4 | 1414 | bio_io_error(bio); |
92c63902 | 1415 | return 0; |
1da177e4 LT |
1416 | } |
1417 | ||
f0b9a450 | 1418 | __split_and_process_bio(md, bio); |
2ca3310e | 1419 | up_read(&md->io_lock); |
f0b9a450 | 1420 | return 0; |
1da177e4 LT |
1421 | } |
1422 | ||
cec47e3d KU |
1423 | static int dm_make_request(struct request_queue *q, struct bio *bio) |
1424 | { | |
1425 | struct mapped_device *md = q->queuedata; | |
1426 | ||
cec47e3d KU |
1427 | return md->saved_make_request_fn(q, bio); /* call __make_request() */ |
1428 | } | |
1429 | ||
1430 | static int dm_request_based(struct mapped_device *md) | |
1431 | { | |
1432 | return blk_queue_stackable(md->queue); | |
1433 | } | |
1434 | ||
1435 | static int dm_request(struct request_queue *q, struct bio *bio) | |
1436 | { | |
1437 | struct mapped_device *md = q->queuedata; | |
1438 | ||
1439 | if (dm_request_based(md)) | |
1440 | return dm_make_request(q, bio); | |
1441 | ||
1442 | return _dm_request(q, bio); | |
1443 | } | |
1444 | ||
1445 | void dm_dispatch_request(struct request *rq) | |
1446 | { | |
1447 | int r; | |
1448 | ||
1449 | if (blk_queue_io_stat(rq->q)) | |
1450 | rq->cmd_flags |= REQ_IO_STAT; | |
1451 | ||
1452 | rq->start_time = jiffies; | |
1453 | r = blk_insert_cloned_request(rq->q, rq); | |
1454 | if (r) | |
1455 | dm_complete_request(rq, r); | |
1456 | } | |
1457 | EXPORT_SYMBOL_GPL(dm_dispatch_request); | |
1458 | ||
1459 | static void dm_rq_bio_destructor(struct bio *bio) | |
1460 | { | |
1461 | struct dm_rq_clone_bio_info *info = bio->bi_private; | |
1462 | struct mapped_device *md = info->tio->md; | |
1463 | ||
1464 | free_bio_info(info); | |
1465 | bio_free(bio, md->bs); | |
1466 | } | |
1467 | ||
1468 | static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig, | |
1469 | void *data) | |
1470 | { | |
1471 | struct dm_rq_target_io *tio = data; | |
1472 | struct mapped_device *md = tio->md; | |
1473 | struct dm_rq_clone_bio_info *info = alloc_bio_info(md); | |
1474 | ||
1475 | if (!info) | |
1476 | return -ENOMEM; | |
1477 | ||
1478 | info->orig = bio_orig; | |
1479 | info->tio = tio; | |
1480 | bio->bi_end_io = end_clone_bio; | |
1481 | bio->bi_private = info; | |
1482 | bio->bi_destructor = dm_rq_bio_destructor; | |
1483 | ||
1484 | return 0; | |
1485 | } | |
1486 | ||
1487 | static int setup_clone(struct request *clone, struct request *rq, | |
1488 | struct dm_rq_target_io *tio) | |
1489 | { | |
d0bcb878 | 1490 | int r; |
cec47e3d | 1491 | |
29e4013d TH |
1492 | r = blk_rq_prep_clone(clone, rq, tio->md->bs, GFP_ATOMIC, |
1493 | dm_rq_bio_constructor, tio); | |
1494 | if (r) | |
1495 | return r; | |
cec47e3d | 1496 | |
29e4013d TH |
1497 | clone->cmd = rq->cmd; |
1498 | clone->cmd_len = rq->cmd_len; | |
1499 | clone->sense = rq->sense; | |
1500 | clone->buffer = rq->buffer; | |
cec47e3d KU |
1501 | clone->end_io = end_clone_request; |
1502 | clone->end_io_data = tio; | |
1503 | ||
1504 | return 0; | |
1505 | } | |
1506 | ||
6facdaff KU |
1507 | static struct request *clone_rq(struct request *rq, struct mapped_device *md, |
1508 | gfp_t gfp_mask) | |
1509 | { | |
1510 | struct request *clone; | |
1511 | struct dm_rq_target_io *tio; | |
1512 | ||
1513 | tio = alloc_rq_tio(md, gfp_mask); | |
1514 | if (!tio) | |
1515 | return NULL; | |
1516 | ||
1517 | tio->md = md; | |
1518 | tio->ti = NULL; | |
1519 | tio->orig = rq; | |
1520 | tio->error = 0; | |
1521 | memset(&tio->info, 0, sizeof(tio->info)); | |
1522 | ||
1523 | clone = &tio->clone; | |
1524 | if (setup_clone(clone, rq, tio)) { | |
1525 | /* -ENOMEM */ | |
1526 | free_rq_tio(tio); | |
1527 | return NULL; | |
1528 | } | |
1529 | ||
1530 | return clone; | |
1531 | } | |
1532 | ||
cec47e3d KU |
1533 | /* |
1534 | * Called with the queue lock held. | |
1535 | */ | |
1536 | static int dm_prep_fn(struct request_queue *q, struct request *rq) | |
1537 | { | |
1538 | struct mapped_device *md = q->queuedata; | |
cec47e3d KU |
1539 | struct request *clone; |
1540 | ||
cec47e3d KU |
1541 | if (unlikely(rq->special)) { |
1542 | DMWARN("Already has something in rq->special."); | |
1543 | return BLKPREP_KILL; | |
1544 | } | |
1545 | ||
6facdaff KU |
1546 | clone = clone_rq(rq, md, GFP_ATOMIC); |
1547 | if (!clone) | |
cec47e3d | 1548 | return BLKPREP_DEFER; |
cec47e3d KU |
1549 | |
1550 | rq->special = clone; | |
1551 | rq->cmd_flags |= REQ_DONTPREP; | |
1552 | ||
1553 | return BLKPREP_OK; | |
1554 | } | |
1555 | ||
9eef87da KU |
1556 | /* |
1557 | * Returns: | |
1558 | * 0 : the request has been processed (not requeued) | |
1559 | * !0 : the request has been requeued | |
1560 | */ | |
1561 | static int map_request(struct dm_target *ti, struct request *clone, | |
1562 | struct mapped_device *md) | |
cec47e3d | 1563 | { |
9eef87da | 1564 | int r, requeued = 0; |
cec47e3d KU |
1565 | struct dm_rq_target_io *tio = clone->end_io_data; |
1566 | ||
1567 | /* | |
1568 | * Hold the md reference here for the in-flight I/O. | |
1569 | * We can't rely on the reference count by device opener, | |
1570 | * because the device may be closed during the request completion | |
1571 | * when all bios are completed. | |
1572 | * See the comment in rq_completed() too. | |
1573 | */ | |
1574 | dm_get(md); | |
1575 | ||
1576 | tio->ti = ti; | |
1577 | r = ti->type->map_rq(ti, clone, &tio->info); | |
1578 | switch (r) { | |
1579 | case DM_MAPIO_SUBMITTED: | |
1580 | /* The target has taken the I/O to submit by itself later */ | |
1581 | break; | |
1582 | case DM_MAPIO_REMAPPED: | |
1583 | /* The target has remapped the I/O so dispatch it */ | |
6db4ccd6 JN |
1584 | trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)), |
1585 | blk_rq_pos(tio->orig)); | |
cec47e3d KU |
1586 | dm_dispatch_request(clone); |
1587 | break; | |
1588 | case DM_MAPIO_REQUEUE: | |
1589 | /* The target wants to requeue the I/O */ | |
1590 | dm_requeue_unmapped_request(clone); | |
9eef87da | 1591 | requeued = 1; |
cec47e3d KU |
1592 | break; |
1593 | default: | |
1594 | if (r > 0) { | |
1595 | DMWARN("unimplemented target map return value: %d", r); | |
1596 | BUG(); | |
1597 | } | |
1598 | ||
1599 | /* The target wants to complete the I/O */ | |
1600 | dm_kill_unmapped_request(clone, r); | |
1601 | break; | |
1602 | } | |
9eef87da KU |
1603 | |
1604 | return requeued; | |
cec47e3d KU |
1605 | } |
1606 | ||
1607 | /* | |
1608 | * q->request_fn for request-based dm. | |
1609 | * Called with the queue lock held. | |
1610 | */ | |
1611 | static void dm_request_fn(struct request_queue *q) | |
1612 | { | |
1613 | struct mapped_device *md = q->queuedata; | |
7c666411 | 1614 | struct dm_table *map = dm_get_live_table(md); |
cec47e3d | 1615 | struct dm_target *ti; |
b4324fee | 1616 | struct request *rq, *clone; |
29e4013d | 1617 | sector_t pos; |
cec47e3d KU |
1618 | |
1619 | /* | |
b4324fee KU |
1620 | * For suspend, check blk_queue_stopped() and increment |
1621 | * ->pending within a single queue_lock not to increment the | |
1622 | * number of in-flight I/Os after the queue is stopped in | |
1623 | * dm_suspend(). | |
cec47e3d | 1624 | */ |
7eaceacc | 1625 | while (!blk_queue_stopped(q)) { |
cec47e3d KU |
1626 | rq = blk_peek_request(q); |
1627 | if (!rq) | |
7eaceacc | 1628 | goto delay_and_out; |
cec47e3d | 1629 | |
29e4013d TH |
1630 | /* always use block 0 to find the target for flushes for now */ |
1631 | pos = 0; | |
1632 | if (!(rq->cmd_flags & REQ_FLUSH)) | |
1633 | pos = blk_rq_pos(rq); | |
1634 | ||
1635 | ti = dm_table_find_target(map, pos); | |
1636 | BUG_ON(!dm_target_is_valid(ti)); | |
d0bcb878 | 1637 | |
cec47e3d | 1638 | if (ti->type->busy && ti->type->busy(ti)) |
7eaceacc | 1639 | goto delay_and_out; |
cec47e3d KU |
1640 | |
1641 | blk_start_request(rq); | |
b4324fee KU |
1642 | clone = rq->special; |
1643 | atomic_inc(&md->pending[rq_data_dir(clone)]); | |
1644 | ||
cec47e3d | 1645 | spin_unlock(q->queue_lock); |
9eef87da KU |
1646 | if (map_request(ti, clone, md)) |
1647 | goto requeued; | |
1648 | ||
052189a2 KU |
1649 | BUG_ON(!irqs_disabled()); |
1650 | spin_lock(q->queue_lock); | |
cec47e3d KU |
1651 | } |
1652 | ||
1653 | goto out; | |
1654 | ||
9eef87da | 1655 | requeued: |
052189a2 KU |
1656 | BUG_ON(!irqs_disabled()); |
1657 | spin_lock(q->queue_lock); | |
9eef87da | 1658 | |
7eaceacc JA |
1659 | delay_and_out: |
1660 | blk_delay_queue(q, HZ / 10); | |
cec47e3d KU |
1661 | out: |
1662 | dm_table_put(map); | |
1663 | ||
1664 | return; | |
1665 | } | |
1666 | ||
1667 | int dm_underlying_device_busy(struct request_queue *q) | |
1668 | { | |
1669 | return blk_lld_busy(q); | |
1670 | } | |
1671 | EXPORT_SYMBOL_GPL(dm_underlying_device_busy); | |
1672 | ||
1673 | static int dm_lld_busy(struct request_queue *q) | |
1674 | { | |
1675 | int r; | |
1676 | struct mapped_device *md = q->queuedata; | |
7c666411 | 1677 | struct dm_table *map = dm_get_live_table(md); |
cec47e3d KU |
1678 | |
1679 | if (!map || test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) | |
1680 | r = 1; | |
1681 | else | |
1682 | r = dm_table_any_busy_target(map); | |
1683 | ||
1684 | dm_table_put(map); | |
1685 | ||
1686 | return r; | |
1687 | } | |
1688 | ||
1da177e4 LT |
1689 | static int dm_any_congested(void *congested_data, int bdi_bits) |
1690 | { | |
8a57dfc6 CS |
1691 | int r = bdi_bits; |
1692 | struct mapped_device *md = congested_data; | |
1693 | struct dm_table *map; | |
1da177e4 | 1694 | |
1eb787ec | 1695 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
7c666411 | 1696 | map = dm_get_live_table(md); |
8a57dfc6 | 1697 | if (map) { |
cec47e3d KU |
1698 | /* |
1699 | * Request-based dm cares about only own queue for | |
1700 | * the query about congestion status of request_queue | |
1701 | */ | |
1702 | if (dm_request_based(md)) | |
1703 | r = md->queue->backing_dev_info.state & | |
1704 | bdi_bits; | |
1705 | else | |
1706 | r = dm_table_any_congested(map, bdi_bits); | |
1707 | ||
8a57dfc6 CS |
1708 | dm_table_put(map); |
1709 | } | |
1710 | } | |
1711 | ||
1da177e4 LT |
1712 | return r; |
1713 | } | |
1714 | ||
1715 | /*----------------------------------------------------------------- | |
1716 | * An IDR is used to keep track of allocated minor numbers. | |
1717 | *---------------------------------------------------------------*/ | |
2b06cfff | 1718 | static void free_minor(int minor) |
1da177e4 | 1719 | { |
f32c10b0 | 1720 | spin_lock(&_minor_lock); |
1da177e4 | 1721 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 1722 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1723 | } |
1724 | ||
1725 | /* | |
1726 | * See if the device with a specific minor # is free. | |
1727 | */ | |
cf13ab8e | 1728 | static int specific_minor(int minor) |
1da177e4 LT |
1729 | { |
1730 | int r, m; | |
1731 | ||
1732 | if (minor >= (1 << MINORBITS)) | |
1733 | return -EINVAL; | |
1734 | ||
62f75c2f JM |
1735 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
1736 | if (!r) | |
1737 | return -ENOMEM; | |
1738 | ||
f32c10b0 | 1739 | spin_lock(&_minor_lock); |
1da177e4 LT |
1740 | |
1741 | if (idr_find(&_minor_idr, minor)) { | |
1742 | r = -EBUSY; | |
1743 | goto out; | |
1744 | } | |
1745 | ||
ba61fdd1 | 1746 | r = idr_get_new_above(&_minor_idr, MINOR_ALLOCED, minor, &m); |
62f75c2f | 1747 | if (r) |
1da177e4 | 1748 | goto out; |
1da177e4 LT |
1749 | |
1750 | if (m != minor) { | |
1751 | idr_remove(&_minor_idr, m); | |
1752 | r = -EBUSY; | |
1753 | goto out; | |
1754 | } | |
1755 | ||
1756 | out: | |
f32c10b0 | 1757 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1758 | return r; |
1759 | } | |
1760 | ||
cf13ab8e | 1761 | static int next_free_minor(int *minor) |
1da177e4 | 1762 | { |
2b06cfff | 1763 | int r, m; |
1da177e4 | 1764 | |
1da177e4 | 1765 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
62f75c2f JM |
1766 | if (!r) |
1767 | return -ENOMEM; | |
1768 | ||
f32c10b0 | 1769 | spin_lock(&_minor_lock); |
1da177e4 | 1770 | |
ba61fdd1 | 1771 | r = idr_get_new(&_minor_idr, MINOR_ALLOCED, &m); |
cf13ab8e | 1772 | if (r) |
1da177e4 | 1773 | goto out; |
1da177e4 LT |
1774 | |
1775 | if (m >= (1 << MINORBITS)) { | |
1776 | idr_remove(&_minor_idr, m); | |
1777 | r = -ENOSPC; | |
1778 | goto out; | |
1779 | } | |
1780 | ||
1781 | *minor = m; | |
1782 | ||
1783 | out: | |
f32c10b0 | 1784 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1785 | return r; |
1786 | } | |
1787 | ||
83d5cde4 | 1788 | static const struct block_device_operations dm_blk_dops; |
1da177e4 | 1789 | |
53d5914f MP |
1790 | static void dm_wq_work(struct work_struct *work); |
1791 | ||
4a0b4ddf MS |
1792 | static void dm_init_md_queue(struct mapped_device *md) |
1793 | { | |
1794 | /* | |
1795 | * Request-based dm devices cannot be stacked on top of bio-based dm | |
1796 | * devices. The type of this dm device has not been decided yet. | |
1797 | * The type is decided at the first table loading time. | |
1798 | * To prevent problematic device stacking, clear the queue flag | |
1799 | * for request stacking support until then. | |
1800 | * | |
1801 | * This queue is new, so no concurrency on the queue_flags. | |
1802 | */ | |
1803 | queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue); | |
1804 | ||
1805 | md->queue->queuedata = md; | |
1806 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
1807 | md->queue->backing_dev_info.congested_data = md; | |
1808 | blk_queue_make_request(md->queue, dm_request); | |
1809 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); | |
4a0b4ddf MS |
1810 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); |
1811 | } | |
1812 | ||
1da177e4 LT |
1813 | /* |
1814 | * Allocate and initialise a blank device with a given minor. | |
1815 | */ | |
2b06cfff | 1816 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
1817 | { |
1818 | int r; | |
cf13ab8e | 1819 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 1820 | void *old_md; |
1da177e4 LT |
1821 | |
1822 | if (!md) { | |
1823 | DMWARN("unable to allocate device, out of memory."); | |
1824 | return NULL; | |
1825 | } | |
1826 | ||
10da4f79 | 1827 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 1828 | goto bad_module_get; |
10da4f79 | 1829 | |
1da177e4 | 1830 | /* get a minor number for the dev */ |
2b06cfff | 1831 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 1832 | r = next_free_minor(&minor); |
2b06cfff | 1833 | else |
cf13ab8e | 1834 | r = specific_minor(minor); |
1da177e4 | 1835 | if (r < 0) |
6ed7ade8 | 1836 | goto bad_minor; |
1da177e4 | 1837 | |
a5664dad | 1838 | md->type = DM_TYPE_NONE; |
2ca3310e | 1839 | init_rwsem(&md->io_lock); |
e61290a4 | 1840 | mutex_init(&md->suspend_lock); |
a5664dad | 1841 | mutex_init(&md->type_lock); |
022c2611 | 1842 | spin_lock_init(&md->deferred_lock); |
1da177e4 LT |
1843 | rwlock_init(&md->map_lock); |
1844 | atomic_set(&md->holders, 1); | |
5c6bd75d | 1845 | atomic_set(&md->open_count, 0); |
1da177e4 | 1846 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
1847 | atomic_set(&md->uevent_seq, 0); |
1848 | INIT_LIST_HEAD(&md->uevent_list); | |
1849 | spin_lock_init(&md->uevent_lock); | |
1da177e4 | 1850 | |
4a0b4ddf | 1851 | md->queue = blk_alloc_queue(GFP_KERNEL); |
1da177e4 | 1852 | if (!md->queue) |
6ed7ade8 | 1853 | goto bad_queue; |
1da177e4 | 1854 | |
4a0b4ddf | 1855 | dm_init_md_queue(md); |
9faf400f | 1856 | |
1da177e4 LT |
1857 | md->disk = alloc_disk(1); |
1858 | if (!md->disk) | |
6ed7ade8 | 1859 | goto bad_disk; |
1da177e4 | 1860 | |
316d315b NK |
1861 | atomic_set(&md->pending[0], 0); |
1862 | atomic_set(&md->pending[1], 0); | |
f0b04115 | 1863 | init_waitqueue_head(&md->wait); |
53d5914f | 1864 | INIT_WORK(&md->work, dm_wq_work); |
f0b04115 JM |
1865 | init_waitqueue_head(&md->eventq); |
1866 | ||
1da177e4 LT |
1867 | md->disk->major = _major; |
1868 | md->disk->first_minor = minor; | |
1869 | md->disk->fops = &dm_blk_dops; | |
1870 | md->disk->queue = md->queue; | |
1871 | md->disk->private_data = md; | |
1872 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
1873 | add_disk(md->disk); | |
7e51f257 | 1874 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 1875 | |
9c4376de TH |
1876 | md->wq = alloc_workqueue("kdmflush", |
1877 | WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0); | |
304f3f6a MB |
1878 | if (!md->wq) |
1879 | goto bad_thread; | |
1880 | ||
32a926da MP |
1881 | md->bdev = bdget_disk(md->disk, 0); |
1882 | if (!md->bdev) | |
1883 | goto bad_bdev; | |
1884 | ||
6a8736d1 TH |
1885 | bio_init(&md->flush_bio); |
1886 | md->flush_bio.bi_bdev = md->bdev; | |
1887 | md->flush_bio.bi_rw = WRITE_FLUSH; | |
1888 | ||
ba61fdd1 | 1889 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 1890 | spin_lock(&_minor_lock); |
ba61fdd1 | 1891 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 1892 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
1893 | |
1894 | BUG_ON(old_md != MINOR_ALLOCED); | |
1895 | ||
1da177e4 LT |
1896 | return md; |
1897 | ||
32a926da MP |
1898 | bad_bdev: |
1899 | destroy_workqueue(md->wq); | |
304f3f6a | 1900 | bad_thread: |
03022c54 | 1901 | del_gendisk(md->disk); |
304f3f6a | 1902 | put_disk(md->disk); |
6ed7ade8 | 1903 | bad_disk: |
1312f40e | 1904 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 1905 | bad_queue: |
1da177e4 | 1906 | free_minor(minor); |
6ed7ade8 | 1907 | bad_minor: |
10da4f79 | 1908 | module_put(THIS_MODULE); |
6ed7ade8 | 1909 | bad_module_get: |
1da177e4 LT |
1910 | kfree(md); |
1911 | return NULL; | |
1912 | } | |
1913 | ||
ae9da83f JN |
1914 | static void unlock_fs(struct mapped_device *md); |
1915 | ||
1da177e4 LT |
1916 | static void free_dev(struct mapped_device *md) |
1917 | { | |
f331c029 | 1918 | int minor = MINOR(disk_devt(md->disk)); |
63d94e48 | 1919 | |
32a926da MP |
1920 | unlock_fs(md); |
1921 | bdput(md->bdev); | |
304f3f6a | 1922 | destroy_workqueue(md->wq); |
e6ee8c0b KU |
1923 | if (md->tio_pool) |
1924 | mempool_destroy(md->tio_pool); | |
1925 | if (md->io_pool) | |
1926 | mempool_destroy(md->io_pool); | |
1927 | if (md->bs) | |
1928 | bioset_free(md->bs); | |
9c47008d | 1929 | blk_integrity_unregister(md->disk); |
1da177e4 | 1930 | del_gendisk(md->disk); |
63d94e48 | 1931 | free_minor(minor); |
fba9f90e JM |
1932 | |
1933 | spin_lock(&_minor_lock); | |
1934 | md->disk->private_data = NULL; | |
1935 | spin_unlock(&_minor_lock); | |
1936 | ||
1da177e4 | 1937 | put_disk(md->disk); |
1312f40e | 1938 | blk_cleanup_queue(md->queue); |
10da4f79 | 1939 | module_put(THIS_MODULE); |
1da177e4 LT |
1940 | kfree(md); |
1941 | } | |
1942 | ||
e6ee8c0b KU |
1943 | static void __bind_mempools(struct mapped_device *md, struct dm_table *t) |
1944 | { | |
1945 | struct dm_md_mempools *p; | |
1946 | ||
1947 | if (md->io_pool && md->tio_pool && md->bs) | |
1948 | /* the md already has necessary mempools */ | |
1949 | goto out; | |
1950 | ||
1951 | p = dm_table_get_md_mempools(t); | |
1952 | BUG_ON(!p || md->io_pool || md->tio_pool || md->bs); | |
1953 | ||
1954 | md->io_pool = p->io_pool; | |
1955 | p->io_pool = NULL; | |
1956 | md->tio_pool = p->tio_pool; | |
1957 | p->tio_pool = NULL; | |
1958 | md->bs = p->bs; | |
1959 | p->bs = NULL; | |
1960 | ||
1961 | out: | |
1962 | /* mempool bind completed, now no need any mempools in the table */ | |
1963 | dm_table_free_md_mempools(t); | |
1964 | } | |
1965 | ||
1da177e4 LT |
1966 | /* |
1967 | * Bind a table to the device. | |
1968 | */ | |
1969 | static void event_callback(void *context) | |
1970 | { | |
7a8c3d3b MA |
1971 | unsigned long flags; |
1972 | LIST_HEAD(uevents); | |
1da177e4 LT |
1973 | struct mapped_device *md = (struct mapped_device *) context; |
1974 | ||
7a8c3d3b MA |
1975 | spin_lock_irqsave(&md->uevent_lock, flags); |
1976 | list_splice_init(&md->uevent_list, &uevents); | |
1977 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
1978 | ||
ed9e1982 | 1979 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
7a8c3d3b | 1980 | |
1da177e4 LT |
1981 | atomic_inc(&md->event_nr); |
1982 | wake_up(&md->eventq); | |
1983 | } | |
1984 | ||
c217649b MS |
1985 | /* |
1986 | * Protected by md->suspend_lock obtained by dm_swap_table(). | |
1987 | */ | |
4e90188b | 1988 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 1989 | { |
4e90188b | 1990 | set_capacity(md->disk, size); |
1da177e4 | 1991 | |
db8fef4f | 1992 | i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
1da177e4 LT |
1993 | } |
1994 | ||
d5b9dd04 MP |
1995 | /* |
1996 | * Return 1 if the queue has a compulsory merge_bvec_fn function. | |
1997 | * | |
1998 | * If this function returns 0, then the device is either a non-dm | |
1999 | * device without a merge_bvec_fn, or it is a dm device that is | |
2000 | * able to split any bios it receives that are too big. | |
2001 | */ | |
2002 | int dm_queue_merge_is_compulsory(struct request_queue *q) | |
2003 | { | |
2004 | struct mapped_device *dev_md; | |
2005 | ||
2006 | if (!q->merge_bvec_fn) | |
2007 | return 0; | |
2008 | ||
2009 | if (q->make_request_fn == dm_request) { | |
2010 | dev_md = q->queuedata; | |
2011 | if (test_bit(DMF_MERGE_IS_OPTIONAL, &dev_md->flags)) | |
2012 | return 0; | |
2013 | } | |
2014 | ||
2015 | return 1; | |
2016 | } | |
2017 | ||
2018 | static int dm_device_merge_is_compulsory(struct dm_target *ti, | |
2019 | struct dm_dev *dev, sector_t start, | |
2020 | sector_t len, void *data) | |
2021 | { | |
2022 | struct block_device *bdev = dev->bdev; | |
2023 | struct request_queue *q = bdev_get_queue(bdev); | |
2024 | ||
2025 | return dm_queue_merge_is_compulsory(q); | |
2026 | } | |
2027 | ||
2028 | /* | |
2029 | * Return 1 if it is acceptable to ignore merge_bvec_fn based | |
2030 | * on the properties of the underlying devices. | |
2031 | */ | |
2032 | static int dm_table_merge_is_optional(struct dm_table *table) | |
2033 | { | |
2034 | unsigned i = 0; | |
2035 | struct dm_target *ti; | |
2036 | ||
2037 | while (i < dm_table_get_num_targets(table)) { | |
2038 | ti = dm_table_get_target(table, i++); | |
2039 | ||
2040 | if (ti->type->iterate_devices && | |
2041 | ti->type->iterate_devices(ti, dm_device_merge_is_compulsory, NULL)) | |
2042 | return 0; | |
2043 | } | |
2044 | ||
2045 | return 1; | |
2046 | } | |
2047 | ||
042d2a9b AK |
2048 | /* |
2049 | * Returns old map, which caller must destroy. | |
2050 | */ | |
2051 | static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, | |
2052 | struct queue_limits *limits) | |
1da177e4 | 2053 | { |
042d2a9b | 2054 | struct dm_table *old_map; |
165125e1 | 2055 | struct request_queue *q = md->queue; |
1da177e4 | 2056 | sector_t size; |
523d9297 | 2057 | unsigned long flags; |
d5b9dd04 | 2058 | int merge_is_optional; |
1da177e4 LT |
2059 | |
2060 | size = dm_table_get_size(t); | |
3ac51e74 DW |
2061 | |
2062 | /* | |
2063 | * Wipe any geometry if the size of the table changed. | |
2064 | */ | |
2065 | if (size != get_capacity(md->disk)) | |
2066 | memset(&md->geometry, 0, sizeof(md->geometry)); | |
2067 | ||
32a926da | 2068 | __set_size(md, size); |
d5816876 | 2069 | |
2ca3310e AK |
2070 | dm_table_event_callback(t, event_callback, md); |
2071 | ||
e6ee8c0b KU |
2072 | /* |
2073 | * The queue hasn't been stopped yet, if the old table type wasn't | |
2074 | * for request-based during suspension. So stop it to prevent | |
2075 | * I/O mapping before resume. | |
2076 | * This must be done before setting the queue restrictions, | |
2077 | * because request-based dm may be run just after the setting. | |
2078 | */ | |
2079 | if (dm_table_request_based(t) && !blk_queue_stopped(q)) | |
2080 | stop_queue(q); | |
2081 | ||
2082 | __bind_mempools(md, t); | |
2083 | ||
d5b9dd04 MP |
2084 | merge_is_optional = dm_table_merge_is_optional(t); |
2085 | ||
523d9297 | 2086 | write_lock_irqsave(&md->map_lock, flags); |
042d2a9b | 2087 | old_map = md->map; |
1da177e4 | 2088 | md->map = t; |
754c5fc7 | 2089 | dm_table_set_restrictions(t, q, limits); |
d5b9dd04 MP |
2090 | if (merge_is_optional) |
2091 | set_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
2092 | else | |
2093 | clear_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
523d9297 | 2094 | write_unlock_irqrestore(&md->map_lock, flags); |
1da177e4 | 2095 | |
042d2a9b | 2096 | return old_map; |
1da177e4 LT |
2097 | } |
2098 | ||
a7940155 AK |
2099 | /* |
2100 | * Returns unbound table for the caller to free. | |
2101 | */ | |
2102 | static struct dm_table *__unbind(struct mapped_device *md) | |
1da177e4 LT |
2103 | { |
2104 | struct dm_table *map = md->map; | |
523d9297 | 2105 | unsigned long flags; |
1da177e4 LT |
2106 | |
2107 | if (!map) | |
a7940155 | 2108 | return NULL; |
1da177e4 LT |
2109 | |
2110 | dm_table_event_callback(map, NULL, NULL); | |
523d9297 | 2111 | write_lock_irqsave(&md->map_lock, flags); |
1da177e4 | 2112 | md->map = NULL; |
523d9297 | 2113 | write_unlock_irqrestore(&md->map_lock, flags); |
a7940155 AK |
2114 | |
2115 | return map; | |
1da177e4 LT |
2116 | } |
2117 | ||
2118 | /* | |
2119 | * Constructor for a new device. | |
2120 | */ | |
2b06cfff | 2121 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
2122 | { |
2123 | struct mapped_device *md; | |
2124 | ||
2b06cfff | 2125 | md = alloc_dev(minor); |
1da177e4 LT |
2126 | if (!md) |
2127 | return -ENXIO; | |
2128 | ||
784aae73 MB |
2129 | dm_sysfs_init(md); |
2130 | ||
1da177e4 LT |
2131 | *result = md; |
2132 | return 0; | |
2133 | } | |
2134 | ||
a5664dad MS |
2135 | /* |
2136 | * Functions to manage md->type. | |
2137 | * All are required to hold md->type_lock. | |
2138 | */ | |
2139 | void dm_lock_md_type(struct mapped_device *md) | |
2140 | { | |
2141 | mutex_lock(&md->type_lock); | |
2142 | } | |
2143 | ||
2144 | void dm_unlock_md_type(struct mapped_device *md) | |
2145 | { | |
2146 | mutex_unlock(&md->type_lock); | |
2147 | } | |
2148 | ||
2149 | void dm_set_md_type(struct mapped_device *md, unsigned type) | |
2150 | { | |
2151 | md->type = type; | |
2152 | } | |
2153 | ||
2154 | unsigned dm_get_md_type(struct mapped_device *md) | |
2155 | { | |
2156 | return md->type; | |
2157 | } | |
2158 | ||
4a0b4ddf MS |
2159 | /* |
2160 | * Fully initialize a request-based queue (->elevator, ->request_fn, etc). | |
2161 | */ | |
2162 | static int dm_init_request_based_queue(struct mapped_device *md) | |
2163 | { | |
2164 | struct request_queue *q = NULL; | |
2165 | ||
2166 | if (md->queue->elevator) | |
2167 | return 1; | |
2168 | ||
2169 | /* Fully initialize the queue */ | |
2170 | q = blk_init_allocated_queue(md->queue, dm_request_fn, NULL); | |
2171 | if (!q) | |
2172 | return 0; | |
2173 | ||
2174 | md->queue = q; | |
2175 | md->saved_make_request_fn = md->queue->make_request_fn; | |
2176 | dm_init_md_queue(md); | |
2177 | blk_queue_softirq_done(md->queue, dm_softirq_done); | |
2178 | blk_queue_prep_rq(md->queue, dm_prep_fn); | |
2179 | blk_queue_lld_busy(md->queue, dm_lld_busy); | |
4a0b4ddf MS |
2180 | |
2181 | elv_register_queue(md->queue); | |
2182 | ||
2183 | return 1; | |
2184 | } | |
2185 | ||
2186 | /* | |
2187 | * Setup the DM device's queue based on md's type | |
2188 | */ | |
2189 | int dm_setup_md_queue(struct mapped_device *md) | |
2190 | { | |
2191 | if ((dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) && | |
2192 | !dm_init_request_based_queue(md)) { | |
2193 | DMWARN("Cannot initialize queue for request-based mapped device"); | |
2194 | return -EINVAL; | |
2195 | } | |
2196 | ||
2197 | return 0; | |
2198 | } | |
2199 | ||
637842cf | 2200 | static struct mapped_device *dm_find_md(dev_t dev) |
1da177e4 LT |
2201 | { |
2202 | struct mapped_device *md; | |
1da177e4 LT |
2203 | unsigned minor = MINOR(dev); |
2204 | ||
2205 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
2206 | return NULL; | |
2207 | ||
f32c10b0 | 2208 | spin_lock(&_minor_lock); |
1da177e4 LT |
2209 | |
2210 | md = idr_find(&_minor_idr, minor); | |
fba9f90e | 2211 | if (md && (md == MINOR_ALLOCED || |
f331c029 | 2212 | (MINOR(disk_devt(dm_disk(md))) != minor) || |
abdc568b | 2213 | dm_deleting_md(md) || |
17b2f66f | 2214 | test_bit(DMF_FREEING, &md->flags))) { |
637842cf | 2215 | md = NULL; |
fba9f90e JM |
2216 | goto out; |
2217 | } | |
1da177e4 | 2218 | |
fba9f90e | 2219 | out: |
f32c10b0 | 2220 | spin_unlock(&_minor_lock); |
1da177e4 | 2221 | |
637842cf DT |
2222 | return md; |
2223 | } | |
2224 | ||
d229a958 DT |
2225 | struct mapped_device *dm_get_md(dev_t dev) |
2226 | { | |
2227 | struct mapped_device *md = dm_find_md(dev); | |
2228 | ||
2229 | if (md) | |
2230 | dm_get(md); | |
2231 | ||
2232 | return md; | |
2233 | } | |
2234 | ||
9ade92a9 | 2235 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 2236 | { |
9ade92a9 | 2237 | return md->interface_ptr; |
1da177e4 LT |
2238 | } |
2239 | ||
2240 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
2241 | { | |
2242 | md->interface_ptr = ptr; | |
2243 | } | |
2244 | ||
2245 | void dm_get(struct mapped_device *md) | |
2246 | { | |
2247 | atomic_inc(&md->holders); | |
3f77316d | 2248 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
1da177e4 LT |
2249 | } |
2250 | ||
72d94861 AK |
2251 | const char *dm_device_name(struct mapped_device *md) |
2252 | { | |
2253 | return md->name; | |
2254 | } | |
2255 | EXPORT_SYMBOL_GPL(dm_device_name); | |
2256 | ||
3f77316d | 2257 | static void __dm_destroy(struct mapped_device *md, bool wait) |
1da177e4 | 2258 | { |
1134e5ae | 2259 | struct dm_table *map; |
1da177e4 | 2260 | |
3f77316d | 2261 | might_sleep(); |
fba9f90e | 2262 | |
3f77316d KU |
2263 | spin_lock(&_minor_lock); |
2264 | map = dm_get_live_table(md); | |
2265 | idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); | |
2266 | set_bit(DMF_FREEING, &md->flags); | |
2267 | spin_unlock(&_minor_lock); | |
2268 | ||
2269 | if (!dm_suspended_md(md)) { | |
2270 | dm_table_presuspend_targets(map); | |
2271 | dm_table_postsuspend_targets(map); | |
1da177e4 | 2272 | } |
3f77316d KU |
2273 | |
2274 | /* | |
2275 | * Rare, but there may be I/O requests still going to complete, | |
2276 | * for example. Wait for all references to disappear. | |
2277 | * No one should increment the reference count of the mapped_device, | |
2278 | * after the mapped_device state becomes DMF_FREEING. | |
2279 | */ | |
2280 | if (wait) | |
2281 | while (atomic_read(&md->holders)) | |
2282 | msleep(1); | |
2283 | else if (atomic_read(&md->holders)) | |
2284 | DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", | |
2285 | dm_device_name(md), atomic_read(&md->holders)); | |
2286 | ||
2287 | dm_sysfs_exit(md); | |
2288 | dm_table_put(map); | |
2289 | dm_table_destroy(__unbind(md)); | |
2290 | free_dev(md); | |
2291 | } | |
2292 | ||
2293 | void dm_destroy(struct mapped_device *md) | |
2294 | { | |
2295 | __dm_destroy(md, true); | |
2296 | } | |
2297 | ||
2298 | void dm_destroy_immediate(struct mapped_device *md) | |
2299 | { | |
2300 | __dm_destroy(md, false); | |
2301 | } | |
2302 | ||
2303 | void dm_put(struct mapped_device *md) | |
2304 | { | |
2305 | atomic_dec(&md->holders); | |
1da177e4 | 2306 | } |
79eb885c | 2307 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 2308 | |
401600df | 2309 | static int dm_wait_for_completion(struct mapped_device *md, int interruptible) |
46125c1c MB |
2310 | { |
2311 | int r = 0; | |
b44ebeb0 MP |
2312 | DECLARE_WAITQUEUE(wait, current); |
2313 | ||
b44ebeb0 | 2314 | add_wait_queue(&md->wait, &wait); |
46125c1c MB |
2315 | |
2316 | while (1) { | |
401600df | 2317 | set_current_state(interruptible); |
46125c1c MB |
2318 | |
2319 | smp_mb(); | |
b4324fee | 2320 | if (!md_in_flight(md)) |
46125c1c MB |
2321 | break; |
2322 | ||
401600df MP |
2323 | if (interruptible == TASK_INTERRUPTIBLE && |
2324 | signal_pending(current)) { | |
46125c1c MB |
2325 | r = -EINTR; |
2326 | break; | |
2327 | } | |
2328 | ||
2329 | io_schedule(); | |
2330 | } | |
2331 | set_current_state(TASK_RUNNING); | |
2332 | ||
b44ebeb0 MP |
2333 | remove_wait_queue(&md->wait, &wait); |
2334 | ||
46125c1c MB |
2335 | return r; |
2336 | } | |
2337 | ||
1da177e4 LT |
2338 | /* |
2339 | * Process the deferred bios | |
2340 | */ | |
ef208587 | 2341 | static void dm_wq_work(struct work_struct *work) |
1da177e4 | 2342 | { |
ef208587 MP |
2343 | struct mapped_device *md = container_of(work, struct mapped_device, |
2344 | work); | |
6d6f10df | 2345 | struct bio *c; |
1da177e4 | 2346 | |
6a8736d1 | 2347 | down_read(&md->io_lock); |
ef208587 | 2348 | |
3b00b203 | 2349 | while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
df12ee99 AK |
2350 | spin_lock_irq(&md->deferred_lock); |
2351 | c = bio_list_pop(&md->deferred); | |
2352 | spin_unlock_irq(&md->deferred_lock); | |
2353 | ||
6a8736d1 | 2354 | if (!c) |
df12ee99 | 2355 | break; |
022c2611 | 2356 | |
6a8736d1 | 2357 | up_read(&md->io_lock); |
3b00b203 | 2358 | |
e6ee8c0b KU |
2359 | if (dm_request_based(md)) |
2360 | generic_make_request(c); | |
6a8736d1 TH |
2361 | else |
2362 | __split_and_process_bio(md, c); | |
3b00b203 | 2363 | |
6a8736d1 | 2364 | down_read(&md->io_lock); |
022c2611 | 2365 | } |
73d410c0 | 2366 | |
6a8736d1 | 2367 | up_read(&md->io_lock); |
1da177e4 LT |
2368 | } |
2369 | ||
9a1fb464 | 2370 | static void dm_queue_flush(struct mapped_device *md) |
304f3f6a | 2371 | { |
3b00b203 MP |
2372 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
2373 | smp_mb__after_clear_bit(); | |
53d5914f | 2374 | queue_work(md->wq, &md->work); |
304f3f6a MB |
2375 | } |
2376 | ||
1da177e4 | 2377 | /* |
042d2a9b | 2378 | * Swap in a new table, returning the old one for the caller to destroy. |
1da177e4 | 2379 | */ |
042d2a9b | 2380 | struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) |
1da177e4 | 2381 | { |
042d2a9b | 2382 | struct dm_table *map = ERR_PTR(-EINVAL); |
754c5fc7 | 2383 | struct queue_limits limits; |
042d2a9b | 2384 | int r; |
1da177e4 | 2385 | |
e61290a4 | 2386 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
2387 | |
2388 | /* device must be suspended */ | |
4f186f8b | 2389 | if (!dm_suspended_md(md)) |
93c534ae | 2390 | goto out; |
1da177e4 | 2391 | |
754c5fc7 | 2392 | r = dm_calculate_queue_limits(table, &limits); |
042d2a9b AK |
2393 | if (r) { |
2394 | map = ERR_PTR(r); | |
754c5fc7 | 2395 | goto out; |
042d2a9b | 2396 | } |
754c5fc7 | 2397 | |
042d2a9b | 2398 | map = __bind(md, table, &limits); |
1da177e4 | 2399 | |
93c534ae | 2400 | out: |
e61290a4 | 2401 | mutex_unlock(&md->suspend_lock); |
042d2a9b | 2402 | return map; |
1da177e4 LT |
2403 | } |
2404 | ||
2405 | /* | |
2406 | * Functions to lock and unlock any filesystem running on the | |
2407 | * device. | |
2408 | */ | |
2ca3310e | 2409 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 2410 | { |
e39e2e95 | 2411 | int r; |
1da177e4 LT |
2412 | |
2413 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 2414 | |
db8fef4f | 2415 | md->frozen_sb = freeze_bdev(md->bdev); |
dfbe03f6 | 2416 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 2417 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
2418 | md->frozen_sb = NULL; |
2419 | return r; | |
dfbe03f6 AK |
2420 | } |
2421 | ||
aa8d7c2f AK |
2422 | set_bit(DMF_FROZEN, &md->flags); |
2423 | ||
1da177e4 LT |
2424 | return 0; |
2425 | } | |
2426 | ||
2ca3310e | 2427 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 2428 | { |
aa8d7c2f AK |
2429 | if (!test_bit(DMF_FROZEN, &md->flags)) |
2430 | return; | |
2431 | ||
db8fef4f | 2432 | thaw_bdev(md->bdev, md->frozen_sb); |
1da177e4 | 2433 | md->frozen_sb = NULL; |
aa8d7c2f | 2434 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
2435 | } |
2436 | ||
2437 | /* | |
2438 | * We need to be able to change a mapping table under a mounted | |
2439 | * filesystem. For example we might want to move some data in | |
2440 | * the background. Before the table can be swapped with | |
2441 | * dm_bind_table, dm_suspend must be called to flush any in | |
2442 | * flight bios and ensure that any further io gets deferred. | |
2443 | */ | |
cec47e3d KU |
2444 | /* |
2445 | * Suspend mechanism in request-based dm. | |
2446 | * | |
9f518b27 KU |
2447 | * 1. Flush all I/Os by lock_fs() if needed. |
2448 | * 2. Stop dispatching any I/O by stopping the request_queue. | |
2449 | * 3. Wait for all in-flight I/Os to be completed or requeued. | |
cec47e3d | 2450 | * |
9f518b27 | 2451 | * To abort suspend, start the request_queue. |
cec47e3d | 2452 | */ |
a3d77d35 | 2453 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) |
1da177e4 | 2454 | { |
2ca3310e | 2455 | struct dm_table *map = NULL; |
46125c1c | 2456 | int r = 0; |
a3d77d35 | 2457 | int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0; |
2e93ccc1 | 2458 | int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0; |
1da177e4 | 2459 | |
e61290a4 | 2460 | mutex_lock(&md->suspend_lock); |
2ca3310e | 2461 | |
4f186f8b | 2462 | if (dm_suspended_md(md)) { |
73d410c0 | 2463 | r = -EINVAL; |
d287483d | 2464 | goto out_unlock; |
73d410c0 | 2465 | } |
1da177e4 | 2466 | |
7c666411 | 2467 | map = dm_get_live_table(md); |
1da177e4 | 2468 | |
2e93ccc1 KU |
2469 | /* |
2470 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
2471 | * This flag is cleared before dm_suspend returns. | |
2472 | */ | |
2473 | if (noflush) | |
2474 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
2475 | ||
cf222b37 AK |
2476 | /* This does not get reverted if there's an error later. */ |
2477 | dm_table_presuspend_targets(map); | |
2478 | ||
32a926da | 2479 | /* |
9f518b27 KU |
2480 | * Flush I/O to the device. |
2481 | * Any I/O submitted after lock_fs() may not be flushed. | |
2482 | * noflush takes precedence over do_lockfs. | |
2483 | * (lock_fs() flushes I/Os and waits for them to complete.) | |
32a926da MP |
2484 | */ |
2485 | if (!noflush && do_lockfs) { | |
2486 | r = lock_fs(md); | |
2487 | if (r) | |
f431d966 | 2488 | goto out; |
aa8d7c2f | 2489 | } |
1da177e4 LT |
2490 | |
2491 | /* | |
3b00b203 MP |
2492 | * Here we must make sure that no processes are submitting requests |
2493 | * to target drivers i.e. no one may be executing | |
2494 | * __split_and_process_bio. This is called from dm_request and | |
2495 | * dm_wq_work. | |
2496 | * | |
2497 | * To get all processes out of __split_and_process_bio in dm_request, | |
2498 | * we take the write lock. To prevent any process from reentering | |
6a8736d1 TH |
2499 | * __split_and_process_bio from dm_request and quiesce the thread |
2500 | * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call | |
2501 | * flush_workqueue(md->wq). | |
1da177e4 | 2502 | */ |
2ca3310e | 2503 | down_write(&md->io_lock); |
1eb787ec | 2504 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
2ca3310e | 2505 | up_write(&md->io_lock); |
1da177e4 | 2506 | |
d0bcb878 | 2507 | /* |
29e4013d TH |
2508 | * Stop md->queue before flushing md->wq in case request-based |
2509 | * dm defers requests to md->wq from md->queue. | |
d0bcb878 | 2510 | */ |
cec47e3d | 2511 | if (dm_request_based(md)) |
9f518b27 | 2512 | stop_queue(md->queue); |
cec47e3d | 2513 | |
d0bcb878 KU |
2514 | flush_workqueue(md->wq); |
2515 | ||
1da177e4 | 2516 | /* |
3b00b203 MP |
2517 | * At this point no more requests are entering target request routines. |
2518 | * We call dm_wait_for_completion to wait for all existing requests | |
2519 | * to finish. | |
1da177e4 | 2520 | */ |
401600df | 2521 | r = dm_wait_for_completion(md, TASK_INTERRUPTIBLE); |
1da177e4 | 2522 | |
2ca3310e | 2523 | down_write(&md->io_lock); |
6d6f10df | 2524 | if (noflush) |
022c2611 | 2525 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
94d6351e | 2526 | up_write(&md->io_lock); |
2e93ccc1 | 2527 | |
1da177e4 | 2528 | /* were we interrupted ? */ |
46125c1c | 2529 | if (r < 0) { |
9a1fb464 | 2530 | dm_queue_flush(md); |
73d410c0 | 2531 | |
cec47e3d | 2532 | if (dm_request_based(md)) |
9f518b27 | 2533 | start_queue(md->queue); |
cec47e3d | 2534 | |
2ca3310e | 2535 | unlock_fs(md); |
2e93ccc1 | 2536 | goto out; /* pushback list is already flushed, so skip flush */ |
2ca3310e | 2537 | } |
1da177e4 | 2538 | |
3b00b203 MP |
2539 | /* |
2540 | * If dm_wait_for_completion returned 0, the device is completely | |
2541 | * quiescent now. There is no request-processing activity. All new | |
2542 | * requests are being added to md->deferred list. | |
2543 | */ | |
2544 | ||
2ca3310e | 2545 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 2546 | |
4d4471cb KU |
2547 | dm_table_postsuspend_targets(map); |
2548 | ||
2ca3310e AK |
2549 | out: |
2550 | dm_table_put(map); | |
d287483d AK |
2551 | |
2552 | out_unlock: | |
e61290a4 | 2553 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 2554 | return r; |
1da177e4 LT |
2555 | } |
2556 | ||
2557 | int dm_resume(struct mapped_device *md) | |
2558 | { | |
cf222b37 | 2559 | int r = -EINVAL; |
cf222b37 | 2560 | struct dm_table *map = NULL; |
1da177e4 | 2561 | |
e61290a4 | 2562 | mutex_lock(&md->suspend_lock); |
4f186f8b | 2563 | if (!dm_suspended_md(md)) |
cf222b37 | 2564 | goto out; |
cf222b37 | 2565 | |
7c666411 | 2566 | map = dm_get_live_table(md); |
2ca3310e | 2567 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 2568 | goto out; |
1da177e4 | 2569 | |
8757b776 MB |
2570 | r = dm_table_resume_targets(map); |
2571 | if (r) | |
2572 | goto out; | |
2ca3310e | 2573 | |
9a1fb464 | 2574 | dm_queue_flush(md); |
2ca3310e | 2575 | |
cec47e3d KU |
2576 | /* |
2577 | * Flushing deferred I/Os must be done after targets are resumed | |
2578 | * so that mapping of targets can work correctly. | |
2579 | * Request-based dm is queueing the deferred I/Os in its request_queue. | |
2580 | */ | |
2581 | if (dm_request_based(md)) | |
2582 | start_queue(md->queue); | |
2583 | ||
2ca3310e AK |
2584 | unlock_fs(md); |
2585 | ||
2586 | clear_bit(DMF_SUSPENDED, &md->flags); | |
2587 | ||
cf222b37 AK |
2588 | r = 0; |
2589 | out: | |
2590 | dm_table_put(map); | |
e61290a4 | 2591 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 2592 | |
cf222b37 | 2593 | return r; |
1da177e4 LT |
2594 | } |
2595 | ||
2596 | /*----------------------------------------------------------------- | |
2597 | * Event notification. | |
2598 | *---------------------------------------------------------------*/ | |
3abf85b5 | 2599 | int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
60935eb2 | 2600 | unsigned cookie) |
69267a30 | 2601 | { |
60935eb2 MB |
2602 | char udev_cookie[DM_COOKIE_LENGTH]; |
2603 | char *envp[] = { udev_cookie, NULL }; | |
2604 | ||
2605 | if (!cookie) | |
3abf85b5 | 2606 | return kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
60935eb2 MB |
2607 | else { |
2608 | snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", | |
2609 | DM_COOKIE_ENV_VAR_NAME, cookie); | |
3abf85b5 PR |
2610 | return kobject_uevent_env(&disk_to_dev(md->disk)->kobj, |
2611 | action, envp); | |
60935eb2 | 2612 | } |
69267a30 AK |
2613 | } |
2614 | ||
7a8c3d3b MA |
2615 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
2616 | { | |
2617 | return atomic_add_return(1, &md->uevent_seq); | |
2618 | } | |
2619 | ||
1da177e4 LT |
2620 | uint32_t dm_get_event_nr(struct mapped_device *md) |
2621 | { | |
2622 | return atomic_read(&md->event_nr); | |
2623 | } | |
2624 | ||
2625 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
2626 | { | |
2627 | return wait_event_interruptible(md->eventq, | |
2628 | (event_nr != atomic_read(&md->event_nr))); | |
2629 | } | |
2630 | ||
7a8c3d3b MA |
2631 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
2632 | { | |
2633 | unsigned long flags; | |
2634 | ||
2635 | spin_lock_irqsave(&md->uevent_lock, flags); | |
2636 | list_add(elist, &md->uevent_list); | |
2637 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2638 | } | |
2639 | ||
1da177e4 LT |
2640 | /* |
2641 | * The gendisk is only valid as long as you have a reference | |
2642 | * count on 'md'. | |
2643 | */ | |
2644 | struct gendisk *dm_disk(struct mapped_device *md) | |
2645 | { | |
2646 | return md->disk; | |
2647 | } | |
2648 | ||
784aae73 MB |
2649 | struct kobject *dm_kobject(struct mapped_device *md) |
2650 | { | |
2651 | return &md->kobj; | |
2652 | } | |
2653 | ||
2654 | /* | |
2655 | * struct mapped_device should not be exported outside of dm.c | |
2656 | * so use this check to verify that kobj is part of md structure | |
2657 | */ | |
2658 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) | |
2659 | { | |
2660 | struct mapped_device *md; | |
2661 | ||
2662 | md = container_of(kobj, struct mapped_device, kobj); | |
2663 | if (&md->kobj != kobj) | |
2664 | return NULL; | |
2665 | ||
4d89b7b4 | 2666 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 2667 | dm_deleting_md(md)) |
4d89b7b4 MB |
2668 | return NULL; |
2669 | ||
784aae73 MB |
2670 | dm_get(md); |
2671 | return md; | |
2672 | } | |
2673 | ||
4f186f8b | 2674 | int dm_suspended_md(struct mapped_device *md) |
1da177e4 LT |
2675 | { |
2676 | return test_bit(DMF_SUSPENDED, &md->flags); | |
2677 | } | |
2678 | ||
64dbce58 KU |
2679 | int dm_suspended(struct dm_target *ti) |
2680 | { | |
ecdb2e25 | 2681 | return dm_suspended_md(dm_table_get_md(ti->table)); |
64dbce58 KU |
2682 | } |
2683 | EXPORT_SYMBOL_GPL(dm_suspended); | |
2684 | ||
2e93ccc1 KU |
2685 | int dm_noflush_suspending(struct dm_target *ti) |
2686 | { | |
ecdb2e25 | 2687 | return __noflush_suspending(dm_table_get_md(ti->table)); |
2e93ccc1 KU |
2688 | } |
2689 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
2690 | ||
a91a2785 | 2691 | struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity) |
e6ee8c0b KU |
2692 | { |
2693 | struct dm_md_mempools *pools = kmalloc(sizeof(*pools), GFP_KERNEL); | |
a91a2785 | 2694 | unsigned int pool_size = (type == DM_TYPE_BIO_BASED) ? 16 : MIN_IOS; |
e6ee8c0b KU |
2695 | |
2696 | if (!pools) | |
2697 | return NULL; | |
2698 | ||
2699 | pools->io_pool = (type == DM_TYPE_BIO_BASED) ? | |
2700 | mempool_create_slab_pool(MIN_IOS, _io_cache) : | |
2701 | mempool_create_slab_pool(MIN_IOS, _rq_bio_info_cache); | |
2702 | if (!pools->io_pool) | |
2703 | goto free_pools_and_out; | |
2704 | ||
2705 | pools->tio_pool = (type == DM_TYPE_BIO_BASED) ? | |
2706 | mempool_create_slab_pool(MIN_IOS, _tio_cache) : | |
2707 | mempool_create_slab_pool(MIN_IOS, _rq_tio_cache); | |
2708 | if (!pools->tio_pool) | |
2709 | goto free_io_pool_and_out; | |
2710 | ||
a91a2785 | 2711 | pools->bs = bioset_create(pool_size, 0); |
e6ee8c0b KU |
2712 | if (!pools->bs) |
2713 | goto free_tio_pool_and_out; | |
2714 | ||
a91a2785 MP |
2715 | if (integrity && bioset_integrity_create(pools->bs, pool_size)) |
2716 | goto free_bioset_and_out; | |
2717 | ||
e6ee8c0b KU |
2718 | return pools; |
2719 | ||
a91a2785 MP |
2720 | free_bioset_and_out: |
2721 | bioset_free(pools->bs); | |
2722 | ||
e6ee8c0b KU |
2723 | free_tio_pool_and_out: |
2724 | mempool_destroy(pools->tio_pool); | |
2725 | ||
2726 | free_io_pool_and_out: | |
2727 | mempool_destroy(pools->io_pool); | |
2728 | ||
2729 | free_pools_and_out: | |
2730 | kfree(pools); | |
2731 | ||
2732 | return NULL; | |
2733 | } | |
2734 | ||
2735 | void dm_free_md_mempools(struct dm_md_mempools *pools) | |
2736 | { | |
2737 | if (!pools) | |
2738 | return; | |
2739 | ||
2740 | if (pools->io_pool) | |
2741 | mempool_destroy(pools->io_pool); | |
2742 | ||
2743 | if (pools->tio_pool) | |
2744 | mempool_destroy(pools->tio_pool); | |
2745 | ||
2746 | if (pools->bs) | |
2747 | bioset_free(pools->bs); | |
2748 | ||
2749 | kfree(pools); | |
2750 | } | |
2751 | ||
83d5cde4 | 2752 | static const struct block_device_operations dm_blk_dops = { |
1da177e4 LT |
2753 | .open = dm_blk_open, |
2754 | .release = dm_blk_close, | |
aa129a22 | 2755 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 2756 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
2757 | .owner = THIS_MODULE |
2758 | }; | |
2759 | ||
2760 | EXPORT_SYMBOL(dm_get_mapinfo); | |
2761 | ||
2762 | /* | |
2763 | * module hooks | |
2764 | */ | |
2765 | module_init(dm_init); | |
2766 | module_exit(dm_exit); | |
2767 | ||
2768 | module_param(major, uint, 0); | |
2769 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
2770 | MODULE_DESCRIPTION(DM_NAME " driver"); | |
2771 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
2772 | MODULE_LICENSE("GPL"); |