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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> | |
6e9624b8 | 18 | #include <linux/smp_lock.h> |
1da177e4 LT |
19 | #include <linux/mempool.h> |
20 | #include <linux/slab.h> | |
21 | #include <linux/idr.h> | |
3ac51e74 | 22 | #include <linux/hdreg.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 | ||
f32c10b0 | 40 | static DEFINE_SPINLOCK(_minor_lock); |
1da177e4 | 41 | /* |
8fbf26ad | 42 | * For bio-based dm. |
1da177e4 LT |
43 | * One of these is allocated per bio. |
44 | */ | |
45 | struct dm_io { | |
46 | struct mapped_device *md; | |
47 | int error; | |
1da177e4 | 48 | atomic_t io_count; |
6ae2fa67 | 49 | struct bio *bio; |
3eaf840e | 50 | unsigned long start_time; |
f88fb981 | 51 | spinlock_t endio_lock; |
1da177e4 LT |
52 | }; |
53 | ||
54 | /* | |
8fbf26ad | 55 | * For bio-based dm. |
1da177e4 LT |
56 | * One of these is allocated per target within a bio. Hopefully |
57 | * this will be simplified out one day. | |
58 | */ | |
028867ac | 59 | struct dm_target_io { |
1da177e4 LT |
60 | struct dm_io *io; |
61 | struct dm_target *ti; | |
62 | union map_info info; | |
63 | }; | |
64 | ||
8fbf26ad KU |
65 | /* |
66 | * For request-based dm. | |
67 | * One of these is allocated per request. | |
68 | */ | |
69 | struct dm_rq_target_io { | |
70 | struct mapped_device *md; | |
71 | struct dm_target *ti; | |
72 | struct request *orig, clone; | |
73 | int error; | |
74 | union map_info info; | |
75 | }; | |
76 | ||
77 | /* | |
78 | * For request-based dm. | |
79 | * One of these is allocated per bio. | |
80 | */ | |
81 | struct dm_rq_clone_bio_info { | |
82 | struct bio *orig; | |
cec47e3d | 83 | struct dm_rq_target_io *tio; |
8fbf26ad KU |
84 | }; |
85 | ||
1da177e4 LT |
86 | union map_info *dm_get_mapinfo(struct bio *bio) |
87 | { | |
17b2f66f | 88 | if (bio && bio->bi_private) |
028867ac | 89 | return &((struct dm_target_io *)bio->bi_private)->info; |
17b2f66f | 90 | return NULL; |
1da177e4 LT |
91 | } |
92 | ||
cec47e3d KU |
93 | union map_info *dm_get_rq_mapinfo(struct request *rq) |
94 | { | |
95 | if (rq && rq->end_io_data) | |
96 | return &((struct dm_rq_target_io *)rq->end_io_data)->info; | |
97 | return NULL; | |
98 | } | |
99 | EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo); | |
100 | ||
ba61fdd1 JM |
101 | #define MINOR_ALLOCED ((void *)-1) |
102 | ||
1da177e4 LT |
103 | /* |
104 | * Bits for the md->flags field. | |
105 | */ | |
1eb787ec | 106 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
1da177e4 | 107 | #define DMF_SUSPENDED 1 |
aa8d7c2f | 108 | #define DMF_FROZEN 2 |
fba9f90e | 109 | #define DMF_FREEING 3 |
5c6bd75d | 110 | #define DMF_DELETING 4 |
2e93ccc1 | 111 | #define DMF_NOFLUSH_SUSPENDING 5 |
1eb787ec | 112 | #define DMF_QUEUE_IO_TO_THREAD 6 |
1da177e4 | 113 | |
304f3f6a MB |
114 | /* |
115 | * Work processed by per-device workqueue. | |
116 | */ | |
1da177e4 | 117 | struct mapped_device { |
2ca3310e | 118 | struct rw_semaphore io_lock; |
e61290a4 | 119 | struct mutex suspend_lock; |
1da177e4 LT |
120 | rwlock_t map_lock; |
121 | atomic_t holders; | |
5c6bd75d | 122 | atomic_t open_count; |
1da177e4 LT |
123 | |
124 | unsigned long flags; | |
125 | ||
165125e1 | 126 | struct request_queue *queue; |
1da177e4 | 127 | struct gendisk *disk; |
7e51f257 | 128 | char name[16]; |
1da177e4 LT |
129 | |
130 | void *interface_ptr; | |
131 | ||
132 | /* | |
133 | * A list of ios that arrived while we were suspended. | |
134 | */ | |
316d315b | 135 | atomic_t pending[2]; |
1da177e4 | 136 | wait_queue_head_t wait; |
53d5914f | 137 | struct work_struct work; |
74859364 | 138 | struct bio_list deferred; |
022c2611 | 139 | spinlock_t deferred_lock; |
1da177e4 | 140 | |
af7e466a MP |
141 | /* |
142 | * An error from the barrier request currently being processed. | |
143 | */ | |
144 | int barrier_error; | |
145 | ||
d0bcb878 KU |
146 | /* |
147 | * Protect barrier_error from concurrent endio processing | |
148 | * in request-based dm. | |
149 | */ | |
150 | spinlock_t barrier_error_lock; | |
151 | ||
304f3f6a MB |
152 | /* |
153 | * Processing queue (flush/barriers) | |
154 | */ | |
155 | struct workqueue_struct *wq; | |
d0bcb878 KU |
156 | struct work_struct barrier_work; |
157 | ||
158 | /* A pointer to the currently processing pre/post flush request */ | |
159 | struct request *flush_request; | |
304f3f6a | 160 | |
1da177e4 LT |
161 | /* |
162 | * The current mapping. | |
163 | */ | |
164 | struct dm_table *map; | |
165 | ||
166 | /* | |
167 | * io objects are allocated from here. | |
168 | */ | |
169 | mempool_t *io_pool; | |
170 | mempool_t *tio_pool; | |
171 | ||
9faf400f SB |
172 | struct bio_set *bs; |
173 | ||
1da177e4 LT |
174 | /* |
175 | * Event handling. | |
176 | */ | |
177 | atomic_t event_nr; | |
178 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
179 | atomic_t uevent_seq; |
180 | struct list_head uevent_list; | |
181 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
182 | |
183 | /* | |
184 | * freeze/thaw support require holding onto a super block | |
185 | */ | |
186 | struct super_block *frozen_sb; | |
db8fef4f | 187 | struct block_device *bdev; |
3ac51e74 DW |
188 | |
189 | /* forced geometry settings */ | |
190 | struct hd_geometry geometry; | |
784aae73 | 191 | |
cec47e3d KU |
192 | /* For saving the address of __make_request for request based dm */ |
193 | make_request_fn *saved_make_request_fn; | |
194 | ||
784aae73 MB |
195 | /* sysfs handle */ |
196 | struct kobject kobj; | |
52b1fd5a MP |
197 | |
198 | /* zero-length barrier that will be cloned and submitted to targets */ | |
199 | struct bio barrier_bio; | |
1da177e4 LT |
200 | }; |
201 | ||
e6ee8c0b KU |
202 | /* |
203 | * For mempools pre-allocation at the table loading time. | |
204 | */ | |
205 | struct dm_md_mempools { | |
206 | mempool_t *io_pool; | |
207 | mempool_t *tio_pool; | |
208 | struct bio_set *bs; | |
209 | }; | |
210 | ||
1da177e4 | 211 | #define MIN_IOS 256 |
e18b890b CL |
212 | static struct kmem_cache *_io_cache; |
213 | static struct kmem_cache *_tio_cache; | |
8fbf26ad KU |
214 | static struct kmem_cache *_rq_tio_cache; |
215 | static struct kmem_cache *_rq_bio_info_cache; | |
1da177e4 | 216 | |
1da177e4 LT |
217 | static int __init local_init(void) |
218 | { | |
51157b4a | 219 | int r = -ENOMEM; |
1da177e4 | 220 | |
1da177e4 | 221 | /* allocate a slab for the dm_ios */ |
028867ac | 222 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 | 223 | if (!_io_cache) |
51157b4a | 224 | return r; |
1da177e4 LT |
225 | |
226 | /* allocate a slab for the target ios */ | |
028867ac | 227 | _tio_cache = KMEM_CACHE(dm_target_io, 0); |
51157b4a KU |
228 | if (!_tio_cache) |
229 | goto out_free_io_cache; | |
1da177e4 | 230 | |
8fbf26ad KU |
231 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
232 | if (!_rq_tio_cache) | |
233 | goto out_free_tio_cache; | |
234 | ||
235 | _rq_bio_info_cache = KMEM_CACHE(dm_rq_clone_bio_info, 0); | |
236 | if (!_rq_bio_info_cache) | |
237 | goto out_free_rq_tio_cache; | |
238 | ||
51e5b2bd | 239 | r = dm_uevent_init(); |
51157b4a | 240 | if (r) |
8fbf26ad | 241 | goto out_free_rq_bio_info_cache; |
51e5b2bd | 242 | |
1da177e4 LT |
243 | _major = major; |
244 | r = register_blkdev(_major, _name); | |
51157b4a KU |
245 | if (r < 0) |
246 | goto out_uevent_exit; | |
1da177e4 LT |
247 | |
248 | if (!_major) | |
249 | _major = r; | |
250 | ||
251 | return 0; | |
51157b4a KU |
252 | |
253 | out_uevent_exit: | |
254 | dm_uevent_exit(); | |
8fbf26ad KU |
255 | out_free_rq_bio_info_cache: |
256 | kmem_cache_destroy(_rq_bio_info_cache); | |
257 | out_free_rq_tio_cache: | |
258 | kmem_cache_destroy(_rq_tio_cache); | |
51157b4a KU |
259 | out_free_tio_cache: |
260 | kmem_cache_destroy(_tio_cache); | |
261 | out_free_io_cache: | |
262 | kmem_cache_destroy(_io_cache); | |
263 | ||
264 | return r; | |
1da177e4 LT |
265 | } |
266 | ||
267 | static void local_exit(void) | |
268 | { | |
8fbf26ad KU |
269 | kmem_cache_destroy(_rq_bio_info_cache); |
270 | kmem_cache_destroy(_rq_tio_cache); | |
1da177e4 LT |
271 | kmem_cache_destroy(_tio_cache); |
272 | kmem_cache_destroy(_io_cache); | |
00d59405 | 273 | unregister_blkdev(_major, _name); |
51e5b2bd | 274 | dm_uevent_exit(); |
1da177e4 LT |
275 | |
276 | _major = 0; | |
277 | ||
278 | DMINFO("cleaned up"); | |
279 | } | |
280 | ||
b9249e55 | 281 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
282 | local_init, |
283 | dm_target_init, | |
284 | dm_linear_init, | |
285 | dm_stripe_init, | |
952b3557 | 286 | dm_io_init, |
945fa4d2 | 287 | dm_kcopyd_init, |
1da177e4 LT |
288 | dm_interface_init, |
289 | }; | |
290 | ||
b9249e55 | 291 | static void (*_exits[])(void) = { |
1da177e4 LT |
292 | local_exit, |
293 | dm_target_exit, | |
294 | dm_linear_exit, | |
295 | dm_stripe_exit, | |
952b3557 | 296 | dm_io_exit, |
945fa4d2 | 297 | dm_kcopyd_exit, |
1da177e4 LT |
298 | dm_interface_exit, |
299 | }; | |
300 | ||
301 | static int __init dm_init(void) | |
302 | { | |
303 | const int count = ARRAY_SIZE(_inits); | |
304 | ||
305 | int r, i; | |
306 | ||
307 | for (i = 0; i < count; i++) { | |
308 | r = _inits[i](); | |
309 | if (r) | |
310 | goto bad; | |
311 | } | |
312 | ||
313 | return 0; | |
314 | ||
315 | bad: | |
316 | while (i--) | |
317 | _exits[i](); | |
318 | ||
319 | return r; | |
320 | } | |
321 | ||
322 | static void __exit dm_exit(void) | |
323 | { | |
324 | int i = ARRAY_SIZE(_exits); | |
325 | ||
326 | while (i--) | |
327 | _exits[i](); | |
328 | } | |
329 | ||
330 | /* | |
331 | * Block device functions | |
332 | */ | |
432a212c MA |
333 | int dm_deleting_md(struct mapped_device *md) |
334 | { | |
335 | return test_bit(DMF_DELETING, &md->flags); | |
336 | } | |
337 | ||
fe5f9f2c | 338 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
339 | { |
340 | struct mapped_device *md; | |
341 | ||
6e9624b8 | 342 | lock_kernel(); |
fba9f90e JM |
343 | spin_lock(&_minor_lock); |
344 | ||
fe5f9f2c | 345 | md = bdev->bd_disk->private_data; |
fba9f90e JM |
346 | if (!md) |
347 | goto out; | |
348 | ||
5c6bd75d | 349 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 350 | dm_deleting_md(md)) { |
fba9f90e JM |
351 | md = NULL; |
352 | goto out; | |
353 | } | |
354 | ||
1da177e4 | 355 | dm_get(md); |
5c6bd75d | 356 | atomic_inc(&md->open_count); |
fba9f90e JM |
357 | |
358 | out: | |
359 | spin_unlock(&_minor_lock); | |
6e9624b8 | 360 | unlock_kernel(); |
fba9f90e JM |
361 | |
362 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
363 | } |
364 | ||
fe5f9f2c | 365 | static int dm_blk_close(struct gendisk *disk, fmode_t mode) |
1da177e4 | 366 | { |
fe5f9f2c | 367 | struct mapped_device *md = disk->private_data; |
6e9624b8 AB |
368 | |
369 | lock_kernel(); | |
5c6bd75d | 370 | atomic_dec(&md->open_count); |
1da177e4 | 371 | dm_put(md); |
6e9624b8 AB |
372 | unlock_kernel(); |
373 | ||
1da177e4 LT |
374 | return 0; |
375 | } | |
376 | ||
5c6bd75d AK |
377 | int dm_open_count(struct mapped_device *md) |
378 | { | |
379 | return atomic_read(&md->open_count); | |
380 | } | |
381 | ||
382 | /* | |
383 | * Guarantees nothing is using the device before it's deleted. | |
384 | */ | |
385 | int dm_lock_for_deletion(struct mapped_device *md) | |
386 | { | |
387 | int r = 0; | |
388 | ||
389 | spin_lock(&_minor_lock); | |
390 | ||
391 | if (dm_open_count(md)) | |
392 | r = -EBUSY; | |
393 | else | |
394 | set_bit(DMF_DELETING, &md->flags); | |
395 | ||
396 | spin_unlock(&_minor_lock); | |
397 | ||
398 | return r; | |
399 | } | |
400 | ||
3ac51e74 DW |
401 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
402 | { | |
403 | struct mapped_device *md = bdev->bd_disk->private_data; | |
404 | ||
405 | return dm_get_geometry(md, geo); | |
406 | } | |
407 | ||
fe5f9f2c | 408 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
aa129a22 MB |
409 | unsigned int cmd, unsigned long arg) |
410 | { | |
fe5f9f2c | 411 | struct mapped_device *md = bdev->bd_disk->private_data; |
7c666411 | 412 | struct dm_table *map = dm_get_live_table(md); |
aa129a22 MB |
413 | struct dm_target *tgt; |
414 | int r = -ENOTTY; | |
415 | ||
aa129a22 MB |
416 | if (!map || !dm_table_get_size(map)) |
417 | goto out; | |
418 | ||
419 | /* We only support devices that have a single target */ | |
420 | if (dm_table_get_num_targets(map) != 1) | |
421 | goto out; | |
422 | ||
423 | tgt = dm_table_get_target(map, 0); | |
424 | ||
4f186f8b | 425 | if (dm_suspended_md(md)) { |
aa129a22 MB |
426 | r = -EAGAIN; |
427 | goto out; | |
428 | } | |
429 | ||
430 | if (tgt->type->ioctl) | |
647b3d00 | 431 | r = tgt->type->ioctl(tgt, cmd, arg); |
aa129a22 MB |
432 | |
433 | out: | |
434 | dm_table_put(map); | |
435 | ||
aa129a22 MB |
436 | return r; |
437 | } | |
438 | ||
028867ac | 439 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
440 | { |
441 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
442 | } | |
443 | ||
028867ac | 444 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
445 | { |
446 | mempool_free(io, md->io_pool); | |
447 | } | |
448 | ||
028867ac | 449 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 LT |
450 | { |
451 | mempool_free(tio, md->tio_pool); | |
452 | } | |
453 | ||
08885643 KU |
454 | static struct dm_rq_target_io *alloc_rq_tio(struct mapped_device *md, |
455 | gfp_t gfp_mask) | |
cec47e3d | 456 | { |
08885643 | 457 | return mempool_alloc(md->tio_pool, gfp_mask); |
cec47e3d KU |
458 | } |
459 | ||
460 | static void free_rq_tio(struct dm_rq_target_io *tio) | |
461 | { | |
462 | mempool_free(tio, tio->md->tio_pool); | |
463 | } | |
464 | ||
465 | static struct dm_rq_clone_bio_info *alloc_bio_info(struct mapped_device *md) | |
466 | { | |
467 | return mempool_alloc(md->io_pool, GFP_ATOMIC); | |
468 | } | |
469 | ||
470 | static void free_bio_info(struct dm_rq_clone_bio_info *info) | |
471 | { | |
472 | mempool_free(info, info->tio->md->io_pool); | |
473 | } | |
474 | ||
90abb8c4 KU |
475 | static int md_in_flight(struct mapped_device *md) |
476 | { | |
477 | return atomic_read(&md->pending[READ]) + | |
478 | atomic_read(&md->pending[WRITE]); | |
479 | } | |
480 | ||
3eaf840e JNN |
481 | static void start_io_acct(struct dm_io *io) |
482 | { | |
483 | struct mapped_device *md = io->md; | |
c9959059 | 484 | int cpu; |
316d315b | 485 | int rw = bio_data_dir(io->bio); |
3eaf840e JNN |
486 | |
487 | io->start_time = jiffies; | |
488 | ||
074a7aca TH |
489 | cpu = part_stat_lock(); |
490 | part_round_stats(cpu, &dm_disk(md)->part0); | |
491 | part_stat_unlock(); | |
316d315b | 492 | dm_disk(md)->part0.in_flight[rw] = atomic_inc_return(&md->pending[rw]); |
3eaf840e JNN |
493 | } |
494 | ||
d221d2e7 | 495 | static void end_io_acct(struct dm_io *io) |
3eaf840e JNN |
496 | { |
497 | struct mapped_device *md = io->md; | |
498 | struct bio *bio = io->bio; | |
499 | unsigned long duration = jiffies - io->start_time; | |
c9959059 | 500 | int pending, cpu; |
3eaf840e JNN |
501 | int rw = bio_data_dir(bio); |
502 | ||
074a7aca TH |
503 | cpu = part_stat_lock(); |
504 | part_round_stats(cpu, &dm_disk(md)->part0); | |
505 | part_stat_add(cpu, &dm_disk(md)->part0, ticks[rw], duration); | |
506 | part_stat_unlock(); | |
3eaf840e | 507 | |
af7e466a MP |
508 | /* |
509 | * After this is decremented the bio must not be touched if it is | |
510 | * a barrier. | |
511 | */ | |
316d315b NK |
512 | dm_disk(md)->part0.in_flight[rw] = pending = |
513 | atomic_dec_return(&md->pending[rw]); | |
514 | pending += atomic_read(&md->pending[rw^0x1]); | |
3eaf840e | 515 | |
d221d2e7 MP |
516 | /* nudge anyone waiting on suspend queue */ |
517 | if (!pending) | |
518 | wake_up(&md->wait); | |
3eaf840e JNN |
519 | } |
520 | ||
1da177e4 LT |
521 | /* |
522 | * Add the bio to the list of deferred io. | |
523 | */ | |
92c63902 | 524 | static void queue_io(struct mapped_device *md, struct bio *bio) |
1da177e4 | 525 | { |
2ca3310e | 526 | down_write(&md->io_lock); |
1da177e4 | 527 | |
022c2611 | 528 | spin_lock_irq(&md->deferred_lock); |
1da177e4 | 529 | bio_list_add(&md->deferred, bio); |
022c2611 | 530 | spin_unlock_irq(&md->deferred_lock); |
1da177e4 | 531 | |
92c63902 MP |
532 | if (!test_and_set_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags)) |
533 | queue_work(md->wq, &md->work); | |
534 | ||
2ca3310e | 535 | up_write(&md->io_lock); |
1da177e4 LT |
536 | } |
537 | ||
538 | /* | |
539 | * Everyone (including functions in this file), should use this | |
540 | * function to access the md->map field, and make sure they call | |
541 | * dm_table_put() when finished. | |
542 | */ | |
7c666411 | 543 | struct dm_table *dm_get_live_table(struct mapped_device *md) |
1da177e4 LT |
544 | { |
545 | struct dm_table *t; | |
523d9297 | 546 | unsigned long flags; |
1da177e4 | 547 | |
523d9297 | 548 | read_lock_irqsave(&md->map_lock, flags); |
1da177e4 LT |
549 | t = md->map; |
550 | if (t) | |
551 | dm_table_get(t); | |
523d9297 | 552 | read_unlock_irqrestore(&md->map_lock, flags); |
1da177e4 LT |
553 | |
554 | return t; | |
555 | } | |
556 | ||
3ac51e74 DW |
557 | /* |
558 | * Get the geometry associated with a dm device | |
559 | */ | |
560 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
561 | { | |
562 | *geo = md->geometry; | |
563 | ||
564 | return 0; | |
565 | } | |
566 | ||
567 | /* | |
568 | * Set the geometry of a device. | |
569 | */ | |
570 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
571 | { | |
572 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
573 | ||
574 | if (geo->start > sz) { | |
575 | DMWARN("Start sector is beyond the geometry limits."); | |
576 | return -EINVAL; | |
577 | } | |
578 | ||
579 | md->geometry = *geo; | |
580 | ||
581 | return 0; | |
582 | } | |
583 | ||
1da177e4 LT |
584 | /*----------------------------------------------------------------- |
585 | * CRUD START: | |
586 | * A more elegant soln is in the works that uses the queue | |
587 | * merge fn, unfortunately there are a couple of changes to | |
588 | * the block layer that I want to make for this. So in the | |
589 | * interests of getting something for people to use I give | |
590 | * you this clearly demarcated crap. | |
591 | *---------------------------------------------------------------*/ | |
592 | ||
2e93ccc1 KU |
593 | static int __noflush_suspending(struct mapped_device *md) |
594 | { | |
595 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
596 | } | |
597 | ||
1da177e4 LT |
598 | /* |
599 | * Decrements the number of outstanding ios that a bio has been | |
600 | * cloned into, completing the original io if necc. | |
601 | */ | |
858119e1 | 602 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 603 | { |
2e93ccc1 | 604 | unsigned long flags; |
b35f8caa MB |
605 | int io_error; |
606 | struct bio *bio; | |
607 | struct mapped_device *md = io->md; | |
2e93ccc1 KU |
608 | |
609 | /* Push-back supersedes any I/O errors */ | |
f88fb981 KU |
610 | if (unlikely(error)) { |
611 | spin_lock_irqsave(&io->endio_lock, flags); | |
612 | if (!(io->error > 0 && __noflush_suspending(md))) | |
613 | io->error = error; | |
614 | spin_unlock_irqrestore(&io->endio_lock, flags); | |
615 | } | |
1da177e4 LT |
616 | |
617 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
618 | if (io->error == DM_ENDIO_REQUEUE) { |
619 | /* | |
620 | * Target requested pushing back the I/O. | |
2e93ccc1 | 621 | */ |
022c2611 | 622 | spin_lock_irqsave(&md->deferred_lock, flags); |
2761e95f | 623 | if (__noflush_suspending(md)) { |
7b6d91da | 624 | if (!(io->bio->bi_rw & REQ_HARDBARRIER)) |
2761e95f MP |
625 | bio_list_add_head(&md->deferred, |
626 | io->bio); | |
627 | } else | |
2e93ccc1 KU |
628 | /* noflush suspend was interrupted. */ |
629 | io->error = -EIO; | |
022c2611 | 630 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
2e93ccc1 KU |
631 | } |
632 | ||
b35f8caa MB |
633 | io_error = io->error; |
634 | bio = io->bio; | |
2e93ccc1 | 635 | |
7b6d91da | 636 | if (bio->bi_rw & REQ_HARDBARRIER) { |
af7e466a MP |
637 | /* |
638 | * There can be just one barrier request so we use | |
639 | * a per-device variable for error reporting. | |
640 | * Note that you can't touch the bio after end_io_acct | |
641 | */ | |
fdb9572b | 642 | if (!md->barrier_error && io_error != -EOPNOTSUPP) |
5aa2781d | 643 | md->barrier_error = io_error; |
af7e466a | 644 | end_io_acct(io); |
a97f925a | 645 | free_io(md, io); |
af7e466a MP |
646 | } else { |
647 | end_io_acct(io); | |
a97f925a | 648 | free_io(md, io); |
b35f8caa | 649 | |
af7e466a MP |
650 | if (io_error != DM_ENDIO_REQUEUE) { |
651 | trace_block_bio_complete(md->queue, bio); | |
2056a782 | 652 | |
af7e466a MP |
653 | bio_endio(bio, io_error); |
654 | } | |
b35f8caa | 655 | } |
1da177e4 LT |
656 | } |
657 | } | |
658 | ||
6712ecf8 | 659 | static void clone_endio(struct bio *bio, int error) |
1da177e4 LT |
660 | { |
661 | int r = 0; | |
028867ac | 662 | struct dm_target_io *tio = bio->bi_private; |
b35f8caa | 663 | struct dm_io *io = tio->io; |
9faf400f | 664 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
665 | dm_endio_fn endio = tio->ti->type->end_io; |
666 | ||
1da177e4 LT |
667 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
668 | error = -EIO; | |
669 | ||
670 | if (endio) { | |
671 | r = endio(tio->ti, bio, error, &tio->info); | |
2e93ccc1 KU |
672 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
673 | /* | |
674 | * error and requeue request are handled | |
675 | * in dec_pending(). | |
676 | */ | |
1da177e4 | 677 | error = r; |
45cbcd79 KU |
678 | else if (r == DM_ENDIO_INCOMPLETE) |
679 | /* The target will handle the io */ | |
6712ecf8 | 680 | return; |
45cbcd79 KU |
681 | else if (r) { |
682 | DMWARN("unimplemented target endio return value: %d", r); | |
683 | BUG(); | |
684 | } | |
1da177e4 LT |
685 | } |
686 | ||
9faf400f SB |
687 | /* |
688 | * Store md for cleanup instead of tio which is about to get freed. | |
689 | */ | |
690 | bio->bi_private = md->bs; | |
691 | ||
9faf400f | 692 | free_tio(md, tio); |
b35f8caa MB |
693 | bio_put(bio); |
694 | dec_pending(io, error); | |
1da177e4 LT |
695 | } |
696 | ||
cec47e3d KU |
697 | /* |
698 | * Partial completion handling for request-based dm | |
699 | */ | |
700 | static void end_clone_bio(struct bio *clone, int error) | |
701 | { | |
702 | struct dm_rq_clone_bio_info *info = clone->bi_private; | |
703 | struct dm_rq_target_io *tio = info->tio; | |
704 | struct bio *bio = info->orig; | |
705 | unsigned int nr_bytes = info->orig->bi_size; | |
706 | ||
707 | bio_put(clone); | |
708 | ||
709 | if (tio->error) | |
710 | /* | |
711 | * An error has already been detected on the request. | |
712 | * Once error occurred, just let clone->end_io() handle | |
713 | * the remainder. | |
714 | */ | |
715 | return; | |
716 | else if (error) { | |
717 | /* | |
718 | * Don't notice the error to the upper layer yet. | |
719 | * The error handling decision is made by the target driver, | |
720 | * when the request is completed. | |
721 | */ | |
722 | tio->error = error; | |
723 | return; | |
724 | } | |
725 | ||
726 | /* | |
727 | * I/O for the bio successfully completed. | |
728 | * Notice the data completion to the upper layer. | |
729 | */ | |
730 | ||
731 | /* | |
732 | * bios are processed from the head of the list. | |
733 | * So the completing bio should always be rq->bio. | |
734 | * If it's not, something wrong is happening. | |
735 | */ | |
736 | if (tio->orig->bio != bio) | |
737 | DMERR("bio completion is going in the middle of the request"); | |
738 | ||
739 | /* | |
740 | * Update the original request. | |
741 | * Do not use blk_end_request() here, because it may complete | |
742 | * the original request before the clone, and break the ordering. | |
743 | */ | |
744 | blk_update_request(tio->orig, 0, nr_bytes); | |
745 | } | |
746 | ||
d0bcb878 KU |
747 | static void store_barrier_error(struct mapped_device *md, int error) |
748 | { | |
749 | unsigned long flags; | |
750 | ||
751 | spin_lock_irqsave(&md->barrier_error_lock, flags); | |
752 | /* | |
753 | * Basically, the first error is taken, but: | |
754 | * -EOPNOTSUPP supersedes any I/O error. | |
755 | * Requeue request supersedes any I/O error but -EOPNOTSUPP. | |
756 | */ | |
757 | if (!md->barrier_error || error == -EOPNOTSUPP || | |
758 | (md->barrier_error != -EOPNOTSUPP && | |
759 | error == DM_ENDIO_REQUEUE)) | |
760 | md->barrier_error = error; | |
761 | spin_unlock_irqrestore(&md->barrier_error_lock, flags); | |
762 | } | |
763 | ||
cec47e3d KU |
764 | /* |
765 | * Don't touch any member of the md after calling this function because | |
766 | * the md may be freed in dm_put() at the end of this function. | |
767 | * Or do dm_get() before calling this function and dm_put() later. | |
768 | */ | |
b4324fee | 769 | static void rq_completed(struct mapped_device *md, int rw, int run_queue) |
cec47e3d | 770 | { |
b4324fee | 771 | atomic_dec(&md->pending[rw]); |
cec47e3d KU |
772 | |
773 | /* nudge anyone waiting on suspend queue */ | |
b4324fee | 774 | if (!md_in_flight(md)) |
cec47e3d KU |
775 | wake_up(&md->wait); |
776 | ||
777 | if (run_queue) | |
b4324fee | 778 | blk_run_queue(md->queue); |
cec47e3d KU |
779 | |
780 | /* | |
781 | * dm_put() must be at the end of this function. See the comment above | |
782 | */ | |
783 | dm_put(md); | |
784 | } | |
785 | ||
a77e28c7 KU |
786 | static void free_rq_clone(struct request *clone) |
787 | { | |
788 | struct dm_rq_target_io *tio = clone->end_io_data; | |
789 | ||
790 | blk_rq_unprep_clone(clone); | |
791 | free_rq_tio(tio); | |
792 | } | |
793 | ||
980691e5 KU |
794 | /* |
795 | * Complete the clone and the original request. | |
796 | * Must be called without queue lock. | |
797 | */ | |
798 | static void dm_end_request(struct request *clone, int error) | |
799 | { | |
800 | int rw = rq_data_dir(clone); | |
d0bcb878 | 801 | int run_queue = 1; |
33659ebb | 802 | bool is_barrier = clone->cmd_flags & REQ_HARDBARRIER; |
980691e5 KU |
803 | struct dm_rq_target_io *tio = clone->end_io_data; |
804 | struct mapped_device *md = tio->md; | |
805 | struct request *rq = tio->orig; | |
806 | ||
33659ebb | 807 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC && !is_barrier) { |
980691e5 KU |
808 | rq->errors = clone->errors; |
809 | rq->resid_len = clone->resid_len; | |
810 | ||
811 | if (rq->sense) | |
812 | /* | |
813 | * We are using the sense buffer of the original | |
814 | * request. | |
815 | * So setting the length of the sense data is enough. | |
816 | */ | |
817 | rq->sense_len = clone->sense_len; | |
818 | } | |
819 | ||
820 | free_rq_clone(clone); | |
821 | ||
d0bcb878 KU |
822 | if (unlikely(is_barrier)) { |
823 | if (unlikely(error)) | |
824 | store_barrier_error(md, error); | |
825 | run_queue = 0; | |
826 | } else | |
827 | blk_end_request_all(rq, error); | |
980691e5 | 828 | |
d0bcb878 | 829 | rq_completed(md, rw, run_queue); |
980691e5 KU |
830 | } |
831 | ||
cec47e3d KU |
832 | static void dm_unprep_request(struct request *rq) |
833 | { | |
834 | struct request *clone = rq->special; | |
cec47e3d KU |
835 | |
836 | rq->special = NULL; | |
837 | rq->cmd_flags &= ~REQ_DONTPREP; | |
838 | ||
a77e28c7 | 839 | free_rq_clone(clone); |
cec47e3d KU |
840 | } |
841 | ||
842 | /* | |
843 | * Requeue the original request of a clone. | |
844 | */ | |
845 | void dm_requeue_unmapped_request(struct request *clone) | |
846 | { | |
b4324fee | 847 | int rw = rq_data_dir(clone); |
cec47e3d KU |
848 | struct dm_rq_target_io *tio = clone->end_io_data; |
849 | struct mapped_device *md = tio->md; | |
850 | struct request *rq = tio->orig; | |
851 | struct request_queue *q = rq->q; | |
852 | unsigned long flags; | |
853 | ||
33659ebb | 854 | if (unlikely(clone->cmd_flags & REQ_HARDBARRIER)) { |
d0bcb878 KU |
855 | /* |
856 | * Barrier clones share an original request. | |
857 | * Leave it to dm_end_request(), which handles this special | |
858 | * case. | |
859 | */ | |
860 | dm_end_request(clone, DM_ENDIO_REQUEUE); | |
861 | return; | |
862 | } | |
863 | ||
cec47e3d KU |
864 | dm_unprep_request(rq); |
865 | ||
866 | spin_lock_irqsave(q->queue_lock, flags); | |
867 | if (elv_queue_empty(q)) | |
868 | blk_plug_device(q); | |
869 | blk_requeue_request(q, rq); | |
870 | spin_unlock_irqrestore(q->queue_lock, flags); | |
871 | ||
b4324fee | 872 | rq_completed(md, rw, 0); |
cec47e3d KU |
873 | } |
874 | EXPORT_SYMBOL_GPL(dm_requeue_unmapped_request); | |
875 | ||
876 | static void __stop_queue(struct request_queue *q) | |
877 | { | |
878 | blk_stop_queue(q); | |
879 | } | |
880 | ||
881 | static void stop_queue(struct request_queue *q) | |
882 | { | |
883 | unsigned long flags; | |
884 | ||
885 | spin_lock_irqsave(q->queue_lock, flags); | |
886 | __stop_queue(q); | |
887 | spin_unlock_irqrestore(q->queue_lock, flags); | |
888 | } | |
889 | ||
890 | static void __start_queue(struct request_queue *q) | |
891 | { | |
892 | if (blk_queue_stopped(q)) | |
893 | blk_start_queue(q); | |
894 | } | |
895 | ||
896 | static void start_queue(struct request_queue *q) | |
897 | { | |
898 | unsigned long flags; | |
899 | ||
900 | spin_lock_irqsave(q->queue_lock, flags); | |
901 | __start_queue(q); | |
902 | spin_unlock_irqrestore(q->queue_lock, flags); | |
903 | } | |
904 | ||
11a68244 | 905 | static void dm_done(struct request *clone, int error, bool mapped) |
cec47e3d | 906 | { |
11a68244 | 907 | int r = error; |
cec47e3d KU |
908 | struct dm_rq_target_io *tio = clone->end_io_data; |
909 | dm_request_endio_fn rq_end_io = tio->ti->type->rq_end_io; | |
cec47e3d | 910 | |
11a68244 KU |
911 | if (mapped && rq_end_io) |
912 | r = rq_end_io(tio->ti, clone, error, &tio->info); | |
cec47e3d | 913 | |
11a68244 | 914 | if (r <= 0) |
cec47e3d | 915 | /* The target wants to complete the I/O */ |
11a68244 KU |
916 | dm_end_request(clone, r); |
917 | else if (r == DM_ENDIO_INCOMPLETE) | |
cec47e3d KU |
918 | /* The target will handle the I/O */ |
919 | return; | |
11a68244 | 920 | else if (r == DM_ENDIO_REQUEUE) |
cec47e3d KU |
921 | /* The target wants to requeue the I/O */ |
922 | dm_requeue_unmapped_request(clone); | |
923 | else { | |
11a68244 | 924 | DMWARN("unimplemented target endio return value: %d", r); |
cec47e3d KU |
925 | BUG(); |
926 | } | |
927 | } | |
928 | ||
11a68244 KU |
929 | /* |
930 | * Request completion handler for request-based dm | |
931 | */ | |
932 | static void dm_softirq_done(struct request *rq) | |
933 | { | |
934 | bool mapped = true; | |
935 | struct request *clone = rq->completion_data; | |
936 | struct dm_rq_target_io *tio = clone->end_io_data; | |
937 | ||
938 | if (rq->cmd_flags & REQ_FAILED) | |
939 | mapped = false; | |
940 | ||
941 | dm_done(clone, tio->error, mapped); | |
942 | } | |
943 | ||
cec47e3d KU |
944 | /* |
945 | * Complete the clone and the original request with the error status | |
946 | * through softirq context. | |
947 | */ | |
948 | static void dm_complete_request(struct request *clone, int error) | |
949 | { | |
950 | struct dm_rq_target_io *tio = clone->end_io_data; | |
951 | struct request *rq = tio->orig; | |
952 | ||
33659ebb | 953 | if (unlikely(clone->cmd_flags & REQ_HARDBARRIER)) { |
d0bcb878 KU |
954 | /* |
955 | * Barrier clones share an original request. So can't use | |
956 | * softirq_done with the original. | |
957 | * Pass the clone to dm_done() directly in this special case. | |
958 | * It is safe (even if clone->q->queue_lock is held here) | |
959 | * because there is no I/O dispatching during the completion | |
960 | * of barrier clone. | |
961 | */ | |
962 | dm_done(clone, error, true); | |
963 | return; | |
964 | } | |
965 | ||
cec47e3d KU |
966 | tio->error = error; |
967 | rq->completion_data = clone; | |
968 | blk_complete_request(rq); | |
969 | } | |
970 | ||
971 | /* | |
972 | * Complete the not-mapped clone and the original request with the error status | |
973 | * through softirq context. | |
974 | * Target's rq_end_io() function isn't called. | |
975 | * This may be used when the target's map_rq() function fails. | |
976 | */ | |
977 | void dm_kill_unmapped_request(struct request *clone, int error) | |
978 | { | |
979 | struct dm_rq_target_io *tio = clone->end_io_data; | |
980 | struct request *rq = tio->orig; | |
981 | ||
33659ebb | 982 | if (unlikely(clone->cmd_flags & REQ_HARDBARRIER)) { |
d0bcb878 KU |
983 | /* |
984 | * Barrier clones share an original request. | |
985 | * Leave it to dm_end_request(), which handles this special | |
986 | * case. | |
987 | */ | |
988 | BUG_ON(error > 0); | |
989 | dm_end_request(clone, error); | |
990 | return; | |
991 | } | |
992 | ||
cec47e3d KU |
993 | rq->cmd_flags |= REQ_FAILED; |
994 | dm_complete_request(clone, error); | |
995 | } | |
996 | EXPORT_SYMBOL_GPL(dm_kill_unmapped_request); | |
997 | ||
998 | /* | |
999 | * Called with the queue lock held | |
1000 | */ | |
1001 | static void end_clone_request(struct request *clone, int error) | |
1002 | { | |
1003 | /* | |
1004 | * For just cleaning up the information of the queue in which | |
1005 | * the clone was dispatched. | |
1006 | * The clone is *NOT* freed actually here because it is alloced from | |
1007 | * dm own mempool and REQ_ALLOCED isn't set in clone->cmd_flags. | |
1008 | */ | |
1009 | __blk_put_request(clone->q, clone); | |
1010 | ||
1011 | /* | |
1012 | * Actual request completion is done in a softirq context which doesn't | |
1013 | * hold the queue lock. Otherwise, deadlock could occur because: | |
1014 | * - another request may be submitted by the upper level driver | |
1015 | * of the stacking during the completion | |
1016 | * - the submission which requires queue lock may be done | |
1017 | * against this queue | |
1018 | */ | |
1019 | dm_complete_request(clone, error); | |
1020 | } | |
1021 | ||
1da177e4 LT |
1022 | static sector_t max_io_len(struct mapped_device *md, |
1023 | sector_t sector, struct dm_target *ti) | |
1024 | { | |
1025 | sector_t offset = sector - ti->begin; | |
1026 | sector_t len = ti->len - offset; | |
1027 | ||
1028 | /* | |
1029 | * Does the target need to split even further ? | |
1030 | */ | |
1031 | if (ti->split_io) { | |
1032 | sector_t boundary; | |
1033 | boundary = ((offset + ti->split_io) & ~(ti->split_io - 1)) | |
1034 | - offset; | |
1035 | if (len > boundary) | |
1036 | len = boundary; | |
1037 | } | |
1038 | ||
1039 | return len; | |
1040 | } | |
1041 | ||
1042 | static void __map_bio(struct dm_target *ti, struct bio *clone, | |
028867ac | 1043 | struct dm_target_io *tio) |
1da177e4 LT |
1044 | { |
1045 | int r; | |
2056a782 | 1046 | sector_t sector; |
9faf400f | 1047 | struct mapped_device *md; |
1da177e4 | 1048 | |
1da177e4 LT |
1049 | clone->bi_end_io = clone_endio; |
1050 | clone->bi_private = tio; | |
1051 | ||
1052 | /* | |
1053 | * Map the clone. If r == 0 we don't need to do | |
1054 | * anything, the target has assumed ownership of | |
1055 | * this io. | |
1056 | */ | |
1057 | atomic_inc(&tio->io->io_count); | |
2056a782 | 1058 | sector = clone->bi_sector; |
1da177e4 | 1059 | r = ti->type->map(ti, clone, &tio->info); |
45cbcd79 | 1060 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 1061 | /* the bio has been remapped so dispatch it */ |
2056a782 | 1062 | |
5f3ea37c | 1063 | trace_block_remap(bdev_get_queue(clone->bi_bdev), clone, |
22a7c31a | 1064 | tio->io->bio->bi_bdev->bd_dev, sector); |
2056a782 | 1065 | |
1da177e4 | 1066 | generic_make_request(clone); |
2e93ccc1 KU |
1067 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
1068 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
1069 | md = tio->io->md; |
1070 | dec_pending(tio->io, r); | |
1071 | /* | |
1072 | * Store bio_set for cleanup. | |
1073 | */ | |
1074 | clone->bi_private = md->bs; | |
1da177e4 | 1075 | bio_put(clone); |
9faf400f | 1076 | free_tio(md, tio); |
45cbcd79 KU |
1077 | } else if (r) { |
1078 | DMWARN("unimplemented target map return value: %d", r); | |
1079 | BUG(); | |
1da177e4 LT |
1080 | } |
1081 | } | |
1082 | ||
1083 | struct clone_info { | |
1084 | struct mapped_device *md; | |
1085 | struct dm_table *map; | |
1086 | struct bio *bio; | |
1087 | struct dm_io *io; | |
1088 | sector_t sector; | |
1089 | sector_t sector_count; | |
1090 | unsigned short idx; | |
1091 | }; | |
1092 | ||
3676347a PO |
1093 | static void dm_bio_destructor(struct bio *bio) |
1094 | { | |
9faf400f SB |
1095 | struct bio_set *bs = bio->bi_private; |
1096 | ||
1097 | bio_free(bio, bs); | |
3676347a PO |
1098 | } |
1099 | ||
1da177e4 LT |
1100 | /* |
1101 | * Creates a little bio that is just does part of a bvec. | |
1102 | */ | |
1103 | static struct bio *split_bvec(struct bio *bio, sector_t sector, | |
1104 | unsigned short idx, unsigned int offset, | |
9faf400f | 1105 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
1106 | { |
1107 | struct bio *clone; | |
1108 | struct bio_vec *bv = bio->bi_io_vec + idx; | |
1109 | ||
9faf400f | 1110 | clone = bio_alloc_bioset(GFP_NOIO, 1, bs); |
3676347a | 1111 | clone->bi_destructor = dm_bio_destructor; |
1da177e4 LT |
1112 | *clone->bi_io_vec = *bv; |
1113 | ||
1114 | clone->bi_sector = sector; | |
1115 | clone->bi_bdev = bio->bi_bdev; | |
7b6d91da | 1116 | clone->bi_rw = bio->bi_rw & ~REQ_HARDBARRIER; |
1da177e4 LT |
1117 | clone->bi_vcnt = 1; |
1118 | clone->bi_size = to_bytes(len); | |
1119 | clone->bi_io_vec->bv_offset = offset; | |
1120 | clone->bi_io_vec->bv_len = clone->bi_size; | |
f3e1d26e | 1121 | clone->bi_flags |= 1 << BIO_CLONED; |
1da177e4 | 1122 | |
9c47008d | 1123 | if (bio_integrity(bio)) { |
7878cba9 | 1124 | bio_integrity_clone(clone, bio, GFP_NOIO, bs); |
9c47008d MP |
1125 | bio_integrity_trim(clone, |
1126 | bio_sector_offset(bio, idx, offset), len); | |
1127 | } | |
1128 | ||
1da177e4 LT |
1129 | return clone; |
1130 | } | |
1131 | ||
1132 | /* | |
1133 | * Creates a bio that consists of range of complete bvecs. | |
1134 | */ | |
1135 | static struct bio *clone_bio(struct bio *bio, sector_t sector, | |
1136 | unsigned short idx, unsigned short bv_count, | |
9faf400f | 1137 | unsigned int len, struct bio_set *bs) |
1da177e4 LT |
1138 | { |
1139 | struct bio *clone; | |
1140 | ||
9faf400f SB |
1141 | clone = bio_alloc_bioset(GFP_NOIO, bio->bi_max_vecs, bs); |
1142 | __bio_clone(clone, bio); | |
7b6d91da | 1143 | clone->bi_rw &= ~REQ_HARDBARRIER; |
9faf400f | 1144 | clone->bi_destructor = dm_bio_destructor; |
1da177e4 LT |
1145 | clone->bi_sector = sector; |
1146 | clone->bi_idx = idx; | |
1147 | clone->bi_vcnt = idx + bv_count; | |
1148 | clone->bi_size = to_bytes(len); | |
1149 | clone->bi_flags &= ~(1 << BIO_SEG_VALID); | |
1150 | ||
9c47008d | 1151 | if (bio_integrity(bio)) { |
7878cba9 | 1152 | bio_integrity_clone(clone, bio, GFP_NOIO, bs); |
9c47008d MP |
1153 | |
1154 | if (idx != bio->bi_idx || clone->bi_size < bio->bi_size) | |
1155 | bio_integrity_trim(clone, | |
1156 | bio_sector_offset(bio, idx, 0), len); | |
1157 | } | |
1158 | ||
1da177e4 LT |
1159 | return clone; |
1160 | } | |
1161 | ||
9015df24 AK |
1162 | static struct dm_target_io *alloc_tio(struct clone_info *ci, |
1163 | struct dm_target *ti) | |
f9ab94ce | 1164 | { |
9015df24 | 1165 | struct dm_target_io *tio = mempool_alloc(ci->md->tio_pool, GFP_NOIO); |
f9ab94ce MP |
1166 | |
1167 | tio->io = ci->io; | |
1168 | tio->ti = ti; | |
f9ab94ce | 1169 | memset(&tio->info, 0, sizeof(tio->info)); |
9015df24 AK |
1170 | |
1171 | return tio; | |
1172 | } | |
1173 | ||
1174 | static void __flush_target(struct clone_info *ci, struct dm_target *ti, | |
1175 | unsigned flush_nr) | |
1176 | { | |
1177 | struct dm_target_io *tio = alloc_tio(ci, ti); | |
1178 | struct bio *clone; | |
1179 | ||
f9ab94ce MP |
1180 | tio->info.flush_request = flush_nr; |
1181 | ||
1182 | clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs); | |
1183 | __bio_clone(clone, ci->bio); | |
1184 | clone->bi_destructor = dm_bio_destructor; | |
1185 | ||
1186 | __map_bio(ti, clone, tio); | |
1187 | } | |
1188 | ||
1189 | static int __clone_and_map_empty_barrier(struct clone_info *ci) | |
1190 | { | |
1191 | unsigned target_nr = 0, flush_nr; | |
1192 | struct dm_target *ti; | |
1193 | ||
1194 | while ((ti = dm_table_get_target(ci->map, target_nr++))) | |
1195 | for (flush_nr = 0; flush_nr < ti->num_flush_requests; | |
1196 | flush_nr++) | |
1197 | __flush_target(ci, ti, flush_nr); | |
1198 | ||
1199 | ci->sector_count = 0; | |
1200 | ||
1201 | return 0; | |
1202 | } | |
1203 | ||
512875bd | 1204 | static int __clone_and_map(struct clone_info *ci) |
1da177e4 LT |
1205 | { |
1206 | struct bio *clone, *bio = ci->bio; | |
512875bd JN |
1207 | struct dm_target *ti; |
1208 | sector_t len = 0, max; | |
028867ac | 1209 | struct dm_target_io *tio; |
1da177e4 | 1210 | |
f9ab94ce MP |
1211 | if (unlikely(bio_empty_barrier(bio))) |
1212 | return __clone_and_map_empty_barrier(ci); | |
1213 | ||
512875bd JN |
1214 | ti = dm_table_find_target(ci->map, ci->sector); |
1215 | if (!dm_target_is_valid(ti)) | |
1216 | return -EIO; | |
1217 | ||
1218 | max = max_io_len(ci->md, ci->sector, ti); | |
1219 | ||
1da177e4 LT |
1220 | /* |
1221 | * Allocate a target io object. | |
1222 | */ | |
9015df24 | 1223 | tio = alloc_tio(ci, ti); |
1da177e4 LT |
1224 | |
1225 | if (ci->sector_count <= max) { | |
1226 | /* | |
1227 | * Optimise for the simple case where we can do all of | |
1228 | * the remaining io with a single clone. | |
1229 | */ | |
1230 | clone = clone_bio(bio, ci->sector, ci->idx, | |
9faf400f SB |
1231 | bio->bi_vcnt - ci->idx, ci->sector_count, |
1232 | ci->md->bs); | |
1da177e4 LT |
1233 | __map_bio(ti, clone, tio); |
1234 | ci->sector_count = 0; | |
1235 | ||
1236 | } else if (to_sector(bio->bi_io_vec[ci->idx].bv_len) <= max) { | |
1237 | /* | |
1238 | * There are some bvecs that don't span targets. | |
1239 | * Do as many of these as possible. | |
1240 | */ | |
1241 | int i; | |
1242 | sector_t remaining = max; | |
1243 | sector_t bv_len; | |
1244 | ||
1245 | for (i = ci->idx; remaining && (i < bio->bi_vcnt); i++) { | |
1246 | bv_len = to_sector(bio->bi_io_vec[i].bv_len); | |
1247 | ||
1248 | if (bv_len > remaining) | |
1249 | break; | |
1250 | ||
1251 | remaining -= bv_len; | |
1252 | len += bv_len; | |
1253 | } | |
1254 | ||
9faf400f SB |
1255 | clone = clone_bio(bio, ci->sector, ci->idx, i - ci->idx, len, |
1256 | ci->md->bs); | |
1da177e4 LT |
1257 | __map_bio(ti, clone, tio); |
1258 | ||
1259 | ci->sector += len; | |
1260 | ci->sector_count -= len; | |
1261 | ci->idx = i; | |
1262 | ||
1263 | } else { | |
1264 | /* | |
d2044a94 | 1265 | * Handle a bvec that must be split between two or more targets. |
1da177e4 LT |
1266 | */ |
1267 | struct bio_vec *bv = bio->bi_io_vec + ci->idx; | |
d2044a94 AK |
1268 | sector_t remaining = to_sector(bv->bv_len); |
1269 | unsigned int offset = 0; | |
1da177e4 | 1270 | |
d2044a94 AK |
1271 | do { |
1272 | if (offset) { | |
1273 | ti = dm_table_find_target(ci->map, ci->sector); | |
512875bd JN |
1274 | if (!dm_target_is_valid(ti)) |
1275 | return -EIO; | |
1276 | ||
d2044a94 | 1277 | max = max_io_len(ci->md, ci->sector, ti); |
1da177e4 | 1278 | |
9015df24 | 1279 | tio = alloc_tio(ci, ti); |
d2044a94 AK |
1280 | } |
1281 | ||
1282 | len = min(remaining, max); | |
1283 | ||
1284 | clone = split_bvec(bio, ci->sector, ci->idx, | |
9faf400f SB |
1285 | bv->bv_offset + offset, len, |
1286 | ci->md->bs); | |
d2044a94 AK |
1287 | |
1288 | __map_bio(ti, clone, tio); | |
1289 | ||
1290 | ci->sector += len; | |
1291 | ci->sector_count -= len; | |
1292 | offset += to_bytes(len); | |
1293 | } while (remaining -= len); | |
1da177e4 | 1294 | |
1da177e4 LT |
1295 | ci->idx++; |
1296 | } | |
512875bd JN |
1297 | |
1298 | return 0; | |
1da177e4 LT |
1299 | } |
1300 | ||
1301 | /* | |
8a53c28d | 1302 | * Split the bio into several clones and submit it to targets. |
1da177e4 | 1303 | */ |
f0b9a450 | 1304 | static void __split_and_process_bio(struct mapped_device *md, struct bio *bio) |
1da177e4 LT |
1305 | { |
1306 | struct clone_info ci; | |
512875bd | 1307 | int error = 0; |
1da177e4 | 1308 | |
7c666411 | 1309 | ci.map = dm_get_live_table(md); |
f0b9a450 | 1310 | if (unlikely(!ci.map)) { |
7b6d91da | 1311 | if (!(bio->bi_rw & REQ_HARDBARRIER)) |
af7e466a MP |
1312 | bio_io_error(bio); |
1313 | else | |
5aa2781d MP |
1314 | if (!md->barrier_error) |
1315 | md->barrier_error = -EIO; | |
f0b9a450 MP |
1316 | return; |
1317 | } | |
692d0eb9 | 1318 | |
1da177e4 LT |
1319 | ci.md = md; |
1320 | ci.bio = bio; | |
1321 | ci.io = alloc_io(md); | |
1322 | ci.io->error = 0; | |
1323 | atomic_set(&ci.io->io_count, 1); | |
1324 | ci.io->bio = bio; | |
1325 | ci.io->md = md; | |
f88fb981 | 1326 | spin_lock_init(&ci.io->endio_lock); |
1da177e4 LT |
1327 | ci.sector = bio->bi_sector; |
1328 | ci.sector_count = bio_sectors(bio); | |
f9ab94ce MP |
1329 | if (unlikely(bio_empty_barrier(bio))) |
1330 | ci.sector_count = 1; | |
1da177e4 LT |
1331 | ci.idx = bio->bi_idx; |
1332 | ||
3eaf840e | 1333 | start_io_acct(ci.io); |
512875bd JN |
1334 | while (ci.sector_count && !error) |
1335 | error = __clone_and_map(&ci); | |
1da177e4 LT |
1336 | |
1337 | /* drop the extra reference count */ | |
512875bd | 1338 | dec_pending(ci.io, error); |
1da177e4 LT |
1339 | dm_table_put(ci.map); |
1340 | } | |
1341 | /*----------------------------------------------------------------- | |
1342 | * CRUD END | |
1343 | *---------------------------------------------------------------*/ | |
1344 | ||
f6fccb12 MB |
1345 | static int dm_merge_bvec(struct request_queue *q, |
1346 | struct bvec_merge_data *bvm, | |
1347 | struct bio_vec *biovec) | |
1348 | { | |
1349 | struct mapped_device *md = q->queuedata; | |
7c666411 | 1350 | struct dm_table *map = dm_get_live_table(md); |
f6fccb12 MB |
1351 | struct dm_target *ti; |
1352 | sector_t max_sectors; | |
5037108a | 1353 | int max_size = 0; |
f6fccb12 MB |
1354 | |
1355 | if (unlikely(!map)) | |
5037108a | 1356 | goto out; |
f6fccb12 MB |
1357 | |
1358 | ti = dm_table_find_target(map, bvm->bi_sector); | |
b01cd5ac MP |
1359 | if (!dm_target_is_valid(ti)) |
1360 | goto out_table; | |
f6fccb12 MB |
1361 | |
1362 | /* | |
1363 | * Find maximum amount of I/O that won't need splitting | |
1364 | */ | |
1365 | max_sectors = min(max_io_len(md, bvm->bi_sector, ti), | |
1366 | (sector_t) BIO_MAX_SECTORS); | |
1367 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; | |
1368 | if (max_size < 0) | |
1369 | max_size = 0; | |
1370 | ||
1371 | /* | |
1372 | * merge_bvec_fn() returns number of bytes | |
1373 | * it can accept at this offset | |
1374 | * max is precomputed maximal io size | |
1375 | */ | |
1376 | if (max_size && ti->type->merge) | |
1377 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
8cbeb67a MP |
1378 | /* |
1379 | * If the target doesn't support merge method and some of the devices | |
1380 | * provided their merge_bvec method (we know this by looking at | |
1381 | * queue_max_hw_sectors), then we can't allow bios with multiple vector | |
1382 | * entries. So always set max_size to 0, and the code below allows | |
1383 | * just one page. | |
1384 | */ | |
1385 | else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9) | |
1386 | ||
1387 | max_size = 0; | |
f6fccb12 | 1388 | |
b01cd5ac | 1389 | out_table: |
5037108a MP |
1390 | dm_table_put(map); |
1391 | ||
1392 | out: | |
f6fccb12 MB |
1393 | /* |
1394 | * Always allow an entire first page | |
1395 | */ | |
1396 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
1397 | max_size = biovec->bv_len; | |
1398 | ||
f6fccb12 MB |
1399 | return max_size; |
1400 | } | |
1401 | ||
1da177e4 LT |
1402 | /* |
1403 | * The request function that just remaps the bio built up by | |
1404 | * dm_merge_bvec. | |
1405 | */ | |
cec47e3d | 1406 | static int _dm_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 1407 | { |
12f03a49 | 1408 | int rw = bio_data_dir(bio); |
1da177e4 | 1409 | struct mapped_device *md = q->queuedata; |
c9959059 | 1410 | int cpu; |
1da177e4 | 1411 | |
2ca3310e | 1412 | down_read(&md->io_lock); |
1da177e4 | 1413 | |
074a7aca TH |
1414 | cpu = part_stat_lock(); |
1415 | part_stat_inc(cpu, &dm_disk(md)->part0, ios[rw]); | |
1416 | part_stat_add(cpu, &dm_disk(md)->part0, sectors[rw], bio_sectors(bio)); | |
1417 | part_stat_unlock(); | |
12f03a49 | 1418 | |
1da177e4 | 1419 | /* |
1eb787ec AK |
1420 | * If we're suspended or the thread is processing barriers |
1421 | * we have to queue this io for later. | |
1da177e4 | 1422 | */ |
af7e466a | 1423 | if (unlikely(test_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags)) || |
7b6d91da | 1424 | unlikely(bio->bi_rw & REQ_HARDBARRIER)) { |
2ca3310e | 1425 | up_read(&md->io_lock); |
1da177e4 | 1426 | |
54d9a1b4 AK |
1427 | if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) && |
1428 | bio_rw(bio) == READA) { | |
1429 | bio_io_error(bio); | |
1430 | return 0; | |
1431 | } | |
1da177e4 | 1432 | |
92c63902 | 1433 | queue_io(md, bio); |
1da177e4 | 1434 | |
92c63902 | 1435 | return 0; |
1da177e4 LT |
1436 | } |
1437 | ||
f0b9a450 | 1438 | __split_and_process_bio(md, bio); |
2ca3310e | 1439 | up_read(&md->io_lock); |
f0b9a450 | 1440 | return 0; |
1da177e4 LT |
1441 | } |
1442 | ||
cec47e3d KU |
1443 | static int dm_make_request(struct request_queue *q, struct bio *bio) |
1444 | { | |
1445 | struct mapped_device *md = q->queuedata; | |
1446 | ||
cec47e3d KU |
1447 | return md->saved_make_request_fn(q, bio); /* call __make_request() */ |
1448 | } | |
1449 | ||
1450 | static int dm_request_based(struct mapped_device *md) | |
1451 | { | |
1452 | return blk_queue_stackable(md->queue); | |
1453 | } | |
1454 | ||
1455 | static int dm_request(struct request_queue *q, struct bio *bio) | |
1456 | { | |
1457 | struct mapped_device *md = q->queuedata; | |
1458 | ||
1459 | if (dm_request_based(md)) | |
1460 | return dm_make_request(q, bio); | |
1461 | ||
1462 | return _dm_request(q, bio); | |
1463 | } | |
1464 | ||
d0bcb878 KU |
1465 | static bool dm_rq_is_flush_request(struct request *rq) |
1466 | { | |
144d6ed5 | 1467 | if (rq->cmd_flags & REQ_FLUSH) |
d0bcb878 KU |
1468 | return true; |
1469 | else | |
1470 | return false; | |
1471 | } | |
1472 | ||
cec47e3d KU |
1473 | void dm_dispatch_request(struct request *rq) |
1474 | { | |
1475 | int r; | |
1476 | ||
1477 | if (blk_queue_io_stat(rq->q)) | |
1478 | rq->cmd_flags |= REQ_IO_STAT; | |
1479 | ||
1480 | rq->start_time = jiffies; | |
1481 | r = blk_insert_cloned_request(rq->q, rq); | |
1482 | if (r) | |
1483 | dm_complete_request(rq, r); | |
1484 | } | |
1485 | EXPORT_SYMBOL_GPL(dm_dispatch_request); | |
1486 | ||
1487 | static void dm_rq_bio_destructor(struct bio *bio) | |
1488 | { | |
1489 | struct dm_rq_clone_bio_info *info = bio->bi_private; | |
1490 | struct mapped_device *md = info->tio->md; | |
1491 | ||
1492 | free_bio_info(info); | |
1493 | bio_free(bio, md->bs); | |
1494 | } | |
1495 | ||
1496 | static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig, | |
1497 | void *data) | |
1498 | { | |
1499 | struct dm_rq_target_io *tio = data; | |
1500 | struct mapped_device *md = tio->md; | |
1501 | struct dm_rq_clone_bio_info *info = alloc_bio_info(md); | |
1502 | ||
1503 | if (!info) | |
1504 | return -ENOMEM; | |
1505 | ||
1506 | info->orig = bio_orig; | |
1507 | info->tio = tio; | |
1508 | bio->bi_end_io = end_clone_bio; | |
1509 | bio->bi_private = info; | |
1510 | bio->bi_destructor = dm_rq_bio_destructor; | |
1511 | ||
1512 | return 0; | |
1513 | } | |
1514 | ||
1515 | static int setup_clone(struct request *clone, struct request *rq, | |
1516 | struct dm_rq_target_io *tio) | |
1517 | { | |
d0bcb878 | 1518 | int r; |
cec47e3d | 1519 | |
d0bcb878 KU |
1520 | if (dm_rq_is_flush_request(rq)) { |
1521 | blk_rq_init(NULL, clone); | |
1522 | clone->cmd_type = REQ_TYPE_FS; | |
1523 | clone->cmd_flags |= (REQ_HARDBARRIER | WRITE); | |
1524 | } else { | |
1525 | r = blk_rq_prep_clone(clone, rq, tio->md->bs, GFP_ATOMIC, | |
1526 | dm_rq_bio_constructor, tio); | |
1527 | if (r) | |
1528 | return r; | |
1529 | ||
1530 | clone->cmd = rq->cmd; | |
1531 | clone->cmd_len = rq->cmd_len; | |
1532 | clone->sense = rq->sense; | |
1533 | clone->buffer = rq->buffer; | |
1534 | } | |
cec47e3d | 1535 | |
cec47e3d KU |
1536 | clone->end_io = end_clone_request; |
1537 | clone->end_io_data = tio; | |
1538 | ||
1539 | return 0; | |
1540 | } | |
1541 | ||
6facdaff KU |
1542 | static struct request *clone_rq(struct request *rq, struct mapped_device *md, |
1543 | gfp_t gfp_mask) | |
1544 | { | |
1545 | struct request *clone; | |
1546 | struct dm_rq_target_io *tio; | |
1547 | ||
1548 | tio = alloc_rq_tio(md, gfp_mask); | |
1549 | if (!tio) | |
1550 | return NULL; | |
1551 | ||
1552 | tio->md = md; | |
1553 | tio->ti = NULL; | |
1554 | tio->orig = rq; | |
1555 | tio->error = 0; | |
1556 | memset(&tio->info, 0, sizeof(tio->info)); | |
1557 | ||
1558 | clone = &tio->clone; | |
1559 | if (setup_clone(clone, rq, tio)) { | |
1560 | /* -ENOMEM */ | |
1561 | free_rq_tio(tio); | |
1562 | return NULL; | |
1563 | } | |
1564 | ||
1565 | return clone; | |
1566 | } | |
1567 | ||
cec47e3d KU |
1568 | /* |
1569 | * Called with the queue lock held. | |
1570 | */ | |
1571 | static int dm_prep_fn(struct request_queue *q, struct request *rq) | |
1572 | { | |
1573 | struct mapped_device *md = q->queuedata; | |
cec47e3d KU |
1574 | struct request *clone; |
1575 | ||
d0bcb878 KU |
1576 | if (unlikely(dm_rq_is_flush_request(rq))) |
1577 | return BLKPREP_OK; | |
1578 | ||
cec47e3d KU |
1579 | if (unlikely(rq->special)) { |
1580 | DMWARN("Already has something in rq->special."); | |
1581 | return BLKPREP_KILL; | |
1582 | } | |
1583 | ||
6facdaff KU |
1584 | clone = clone_rq(rq, md, GFP_ATOMIC); |
1585 | if (!clone) | |
cec47e3d | 1586 | return BLKPREP_DEFER; |
cec47e3d KU |
1587 | |
1588 | rq->special = clone; | |
1589 | rq->cmd_flags |= REQ_DONTPREP; | |
1590 | ||
1591 | return BLKPREP_OK; | |
1592 | } | |
1593 | ||
9eef87da KU |
1594 | /* |
1595 | * Returns: | |
1596 | * 0 : the request has been processed (not requeued) | |
1597 | * !0 : the request has been requeued | |
1598 | */ | |
1599 | static int map_request(struct dm_target *ti, struct request *clone, | |
1600 | struct mapped_device *md) | |
cec47e3d | 1601 | { |
9eef87da | 1602 | int r, requeued = 0; |
cec47e3d KU |
1603 | struct dm_rq_target_io *tio = clone->end_io_data; |
1604 | ||
1605 | /* | |
1606 | * Hold the md reference here for the in-flight I/O. | |
1607 | * We can't rely on the reference count by device opener, | |
1608 | * because the device may be closed during the request completion | |
1609 | * when all bios are completed. | |
1610 | * See the comment in rq_completed() too. | |
1611 | */ | |
1612 | dm_get(md); | |
1613 | ||
1614 | tio->ti = ti; | |
1615 | r = ti->type->map_rq(ti, clone, &tio->info); | |
1616 | switch (r) { | |
1617 | case DM_MAPIO_SUBMITTED: | |
1618 | /* The target has taken the I/O to submit by itself later */ | |
1619 | break; | |
1620 | case DM_MAPIO_REMAPPED: | |
1621 | /* The target has remapped the I/O so dispatch it */ | |
6db4ccd6 JN |
1622 | trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)), |
1623 | blk_rq_pos(tio->orig)); | |
cec47e3d KU |
1624 | dm_dispatch_request(clone); |
1625 | break; | |
1626 | case DM_MAPIO_REQUEUE: | |
1627 | /* The target wants to requeue the I/O */ | |
1628 | dm_requeue_unmapped_request(clone); | |
9eef87da | 1629 | requeued = 1; |
cec47e3d KU |
1630 | break; |
1631 | default: | |
1632 | if (r > 0) { | |
1633 | DMWARN("unimplemented target map return value: %d", r); | |
1634 | BUG(); | |
1635 | } | |
1636 | ||
1637 | /* The target wants to complete the I/O */ | |
1638 | dm_kill_unmapped_request(clone, r); | |
1639 | break; | |
1640 | } | |
9eef87da KU |
1641 | |
1642 | return requeued; | |
cec47e3d KU |
1643 | } |
1644 | ||
1645 | /* | |
1646 | * q->request_fn for request-based dm. | |
1647 | * Called with the queue lock held. | |
1648 | */ | |
1649 | static void dm_request_fn(struct request_queue *q) | |
1650 | { | |
1651 | struct mapped_device *md = q->queuedata; | |
7c666411 | 1652 | struct dm_table *map = dm_get_live_table(md); |
cec47e3d | 1653 | struct dm_target *ti; |
b4324fee | 1654 | struct request *rq, *clone; |
cec47e3d KU |
1655 | |
1656 | /* | |
b4324fee KU |
1657 | * For suspend, check blk_queue_stopped() and increment |
1658 | * ->pending within a single queue_lock not to increment the | |
1659 | * number of in-flight I/Os after the queue is stopped in | |
1660 | * dm_suspend(). | |
cec47e3d KU |
1661 | */ |
1662 | while (!blk_queue_plugged(q) && !blk_queue_stopped(q)) { | |
1663 | rq = blk_peek_request(q); | |
1664 | if (!rq) | |
1665 | goto plug_and_out; | |
1666 | ||
d0bcb878 KU |
1667 | if (unlikely(dm_rq_is_flush_request(rq))) { |
1668 | BUG_ON(md->flush_request); | |
1669 | md->flush_request = rq; | |
1670 | blk_start_request(rq); | |
1671 | queue_work(md->wq, &md->barrier_work); | |
1672 | goto out; | |
1673 | } | |
1674 | ||
cec47e3d KU |
1675 | ti = dm_table_find_target(map, blk_rq_pos(rq)); |
1676 | if (ti->type->busy && ti->type->busy(ti)) | |
1677 | goto plug_and_out; | |
1678 | ||
1679 | blk_start_request(rq); | |
b4324fee KU |
1680 | clone = rq->special; |
1681 | atomic_inc(&md->pending[rq_data_dir(clone)]); | |
1682 | ||
cec47e3d | 1683 | spin_unlock(q->queue_lock); |
9eef87da KU |
1684 | if (map_request(ti, clone, md)) |
1685 | goto requeued; | |
1686 | ||
cec47e3d KU |
1687 | spin_lock_irq(q->queue_lock); |
1688 | } | |
1689 | ||
1690 | goto out; | |
1691 | ||
9eef87da KU |
1692 | requeued: |
1693 | spin_lock_irq(q->queue_lock); | |
1694 | ||
cec47e3d KU |
1695 | plug_and_out: |
1696 | if (!elv_queue_empty(q)) | |
1697 | /* Some requests still remain, retry later */ | |
1698 | blk_plug_device(q); | |
1699 | ||
1700 | out: | |
1701 | dm_table_put(map); | |
1702 | ||
1703 | return; | |
1704 | } | |
1705 | ||
1706 | int dm_underlying_device_busy(struct request_queue *q) | |
1707 | { | |
1708 | return blk_lld_busy(q); | |
1709 | } | |
1710 | EXPORT_SYMBOL_GPL(dm_underlying_device_busy); | |
1711 | ||
1712 | static int dm_lld_busy(struct request_queue *q) | |
1713 | { | |
1714 | int r; | |
1715 | struct mapped_device *md = q->queuedata; | |
7c666411 | 1716 | struct dm_table *map = dm_get_live_table(md); |
cec47e3d KU |
1717 | |
1718 | if (!map || test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) | |
1719 | r = 1; | |
1720 | else | |
1721 | r = dm_table_any_busy_target(map); | |
1722 | ||
1723 | dm_table_put(map); | |
1724 | ||
1725 | return r; | |
1726 | } | |
1727 | ||
165125e1 | 1728 | static void dm_unplug_all(struct request_queue *q) |
1da177e4 LT |
1729 | { |
1730 | struct mapped_device *md = q->queuedata; | |
7c666411 | 1731 | struct dm_table *map = dm_get_live_table(md); |
1da177e4 LT |
1732 | |
1733 | if (map) { | |
cec47e3d KU |
1734 | if (dm_request_based(md)) |
1735 | generic_unplug_device(q); | |
1736 | ||
1da177e4 LT |
1737 | dm_table_unplug_all(map); |
1738 | dm_table_put(map); | |
1739 | } | |
1740 | } | |
1741 | ||
1742 | static int dm_any_congested(void *congested_data, int bdi_bits) | |
1743 | { | |
8a57dfc6 CS |
1744 | int r = bdi_bits; |
1745 | struct mapped_device *md = congested_data; | |
1746 | struct dm_table *map; | |
1da177e4 | 1747 | |
1eb787ec | 1748 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
7c666411 | 1749 | map = dm_get_live_table(md); |
8a57dfc6 | 1750 | if (map) { |
cec47e3d KU |
1751 | /* |
1752 | * Request-based dm cares about only own queue for | |
1753 | * the query about congestion status of request_queue | |
1754 | */ | |
1755 | if (dm_request_based(md)) | |
1756 | r = md->queue->backing_dev_info.state & | |
1757 | bdi_bits; | |
1758 | else | |
1759 | r = dm_table_any_congested(map, bdi_bits); | |
1760 | ||
8a57dfc6 CS |
1761 | dm_table_put(map); |
1762 | } | |
1763 | } | |
1764 | ||
1da177e4 LT |
1765 | return r; |
1766 | } | |
1767 | ||
1768 | /*----------------------------------------------------------------- | |
1769 | * An IDR is used to keep track of allocated minor numbers. | |
1770 | *---------------------------------------------------------------*/ | |
1da177e4 LT |
1771 | static DEFINE_IDR(_minor_idr); |
1772 | ||
2b06cfff | 1773 | static void free_minor(int minor) |
1da177e4 | 1774 | { |
f32c10b0 | 1775 | spin_lock(&_minor_lock); |
1da177e4 | 1776 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 1777 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1778 | } |
1779 | ||
1780 | /* | |
1781 | * See if the device with a specific minor # is free. | |
1782 | */ | |
cf13ab8e | 1783 | static int specific_minor(int minor) |
1da177e4 LT |
1784 | { |
1785 | int r, m; | |
1786 | ||
1787 | if (minor >= (1 << MINORBITS)) | |
1788 | return -EINVAL; | |
1789 | ||
62f75c2f JM |
1790 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
1791 | if (!r) | |
1792 | return -ENOMEM; | |
1793 | ||
f32c10b0 | 1794 | spin_lock(&_minor_lock); |
1da177e4 LT |
1795 | |
1796 | if (idr_find(&_minor_idr, minor)) { | |
1797 | r = -EBUSY; | |
1798 | goto out; | |
1799 | } | |
1800 | ||
ba61fdd1 | 1801 | r = idr_get_new_above(&_minor_idr, MINOR_ALLOCED, minor, &m); |
62f75c2f | 1802 | if (r) |
1da177e4 | 1803 | goto out; |
1da177e4 LT |
1804 | |
1805 | if (m != minor) { | |
1806 | idr_remove(&_minor_idr, m); | |
1807 | r = -EBUSY; | |
1808 | goto out; | |
1809 | } | |
1810 | ||
1811 | out: | |
f32c10b0 | 1812 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1813 | return r; |
1814 | } | |
1815 | ||
cf13ab8e | 1816 | static int next_free_minor(int *minor) |
1da177e4 | 1817 | { |
2b06cfff | 1818 | int r, m; |
1da177e4 | 1819 | |
1da177e4 | 1820 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
62f75c2f JM |
1821 | if (!r) |
1822 | return -ENOMEM; | |
1823 | ||
f32c10b0 | 1824 | spin_lock(&_minor_lock); |
1da177e4 | 1825 | |
ba61fdd1 | 1826 | r = idr_get_new(&_minor_idr, MINOR_ALLOCED, &m); |
cf13ab8e | 1827 | if (r) |
1da177e4 | 1828 | goto out; |
1da177e4 LT |
1829 | |
1830 | if (m >= (1 << MINORBITS)) { | |
1831 | idr_remove(&_minor_idr, m); | |
1832 | r = -ENOSPC; | |
1833 | goto out; | |
1834 | } | |
1835 | ||
1836 | *minor = m; | |
1837 | ||
1838 | out: | |
f32c10b0 | 1839 | spin_unlock(&_minor_lock); |
1da177e4 LT |
1840 | return r; |
1841 | } | |
1842 | ||
83d5cde4 | 1843 | static const struct block_device_operations dm_blk_dops; |
1da177e4 | 1844 | |
53d5914f | 1845 | static void dm_wq_work(struct work_struct *work); |
d0bcb878 | 1846 | static void dm_rq_barrier_work(struct work_struct *work); |
53d5914f | 1847 | |
1da177e4 LT |
1848 | /* |
1849 | * Allocate and initialise a blank device with a given minor. | |
1850 | */ | |
2b06cfff | 1851 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
1852 | { |
1853 | int r; | |
cf13ab8e | 1854 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 1855 | void *old_md; |
1da177e4 LT |
1856 | |
1857 | if (!md) { | |
1858 | DMWARN("unable to allocate device, out of memory."); | |
1859 | return NULL; | |
1860 | } | |
1861 | ||
10da4f79 | 1862 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 1863 | goto bad_module_get; |
10da4f79 | 1864 | |
1da177e4 | 1865 | /* get a minor number for the dev */ |
2b06cfff | 1866 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 1867 | r = next_free_minor(&minor); |
2b06cfff | 1868 | else |
cf13ab8e | 1869 | r = specific_minor(minor); |
1da177e4 | 1870 | if (r < 0) |
6ed7ade8 | 1871 | goto bad_minor; |
1da177e4 | 1872 | |
2ca3310e | 1873 | init_rwsem(&md->io_lock); |
e61290a4 | 1874 | mutex_init(&md->suspend_lock); |
022c2611 | 1875 | spin_lock_init(&md->deferred_lock); |
d0bcb878 | 1876 | spin_lock_init(&md->barrier_error_lock); |
1da177e4 LT |
1877 | rwlock_init(&md->map_lock); |
1878 | atomic_set(&md->holders, 1); | |
5c6bd75d | 1879 | atomic_set(&md->open_count, 0); |
1da177e4 | 1880 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
1881 | atomic_set(&md->uevent_seq, 0); |
1882 | INIT_LIST_HEAD(&md->uevent_list); | |
1883 | spin_lock_init(&md->uevent_lock); | |
1da177e4 | 1884 | |
e6ee8c0b | 1885 | md->queue = blk_init_queue(dm_request_fn, NULL); |
1da177e4 | 1886 | if (!md->queue) |
6ed7ade8 | 1887 | goto bad_queue; |
1da177e4 | 1888 | |
e6ee8c0b KU |
1889 | /* |
1890 | * Request-based dm devices cannot be stacked on top of bio-based dm | |
1891 | * devices. The type of this dm device has not been decided yet, | |
1892 | * although we initialized the queue using blk_init_queue(). | |
1893 | * The type is decided at the first table loading time. | |
1894 | * To prevent problematic device stacking, clear the queue flag | |
1895 | * for request stacking support until then. | |
1896 | * | |
1897 | * This queue is new, so no concurrency on the queue_flags. | |
1898 | */ | |
1899 | queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue); | |
1900 | md->saved_make_request_fn = md->queue->make_request_fn; | |
1da177e4 LT |
1901 | md->queue->queuedata = md; |
1902 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
1903 | md->queue->backing_dev_info.congested_data = md; | |
1904 | blk_queue_make_request(md->queue, dm_request); | |
daef265f | 1905 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); |
1da177e4 | 1906 | md->queue->unplug_fn = dm_unplug_all; |
f6fccb12 | 1907 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); |
e6ee8c0b KU |
1908 | blk_queue_softirq_done(md->queue, dm_softirq_done); |
1909 | blk_queue_prep_rq(md->queue, dm_prep_fn); | |
1910 | blk_queue_lld_busy(md->queue, dm_lld_busy); | |
00fff265 | 1911 | blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN_FLUSH); |
9faf400f | 1912 | |
1da177e4 LT |
1913 | md->disk = alloc_disk(1); |
1914 | if (!md->disk) | |
6ed7ade8 | 1915 | goto bad_disk; |
1da177e4 | 1916 | |
316d315b NK |
1917 | atomic_set(&md->pending[0], 0); |
1918 | atomic_set(&md->pending[1], 0); | |
f0b04115 | 1919 | init_waitqueue_head(&md->wait); |
53d5914f | 1920 | INIT_WORK(&md->work, dm_wq_work); |
d0bcb878 | 1921 | INIT_WORK(&md->barrier_work, dm_rq_barrier_work); |
f0b04115 JM |
1922 | init_waitqueue_head(&md->eventq); |
1923 | ||
1da177e4 LT |
1924 | md->disk->major = _major; |
1925 | md->disk->first_minor = minor; | |
1926 | md->disk->fops = &dm_blk_dops; | |
1927 | md->disk->queue = md->queue; | |
1928 | md->disk->private_data = md; | |
1929 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
1930 | add_disk(md->disk); | |
7e51f257 | 1931 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 1932 | |
304f3f6a MB |
1933 | md->wq = create_singlethread_workqueue("kdmflush"); |
1934 | if (!md->wq) | |
1935 | goto bad_thread; | |
1936 | ||
32a926da MP |
1937 | md->bdev = bdget_disk(md->disk, 0); |
1938 | if (!md->bdev) | |
1939 | goto bad_bdev; | |
1940 | ||
ba61fdd1 | 1941 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 1942 | spin_lock(&_minor_lock); |
ba61fdd1 | 1943 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 1944 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
1945 | |
1946 | BUG_ON(old_md != MINOR_ALLOCED); | |
1947 | ||
1da177e4 LT |
1948 | return md; |
1949 | ||
32a926da MP |
1950 | bad_bdev: |
1951 | destroy_workqueue(md->wq); | |
304f3f6a | 1952 | bad_thread: |
03022c54 | 1953 | del_gendisk(md->disk); |
304f3f6a | 1954 | put_disk(md->disk); |
6ed7ade8 | 1955 | bad_disk: |
1312f40e | 1956 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 1957 | bad_queue: |
1da177e4 | 1958 | free_minor(minor); |
6ed7ade8 | 1959 | bad_minor: |
10da4f79 | 1960 | module_put(THIS_MODULE); |
6ed7ade8 | 1961 | bad_module_get: |
1da177e4 LT |
1962 | kfree(md); |
1963 | return NULL; | |
1964 | } | |
1965 | ||
ae9da83f JN |
1966 | static void unlock_fs(struct mapped_device *md); |
1967 | ||
1da177e4 LT |
1968 | static void free_dev(struct mapped_device *md) |
1969 | { | |
f331c029 | 1970 | int minor = MINOR(disk_devt(md->disk)); |
63d94e48 | 1971 | |
32a926da MP |
1972 | unlock_fs(md); |
1973 | bdput(md->bdev); | |
304f3f6a | 1974 | destroy_workqueue(md->wq); |
e6ee8c0b KU |
1975 | if (md->tio_pool) |
1976 | mempool_destroy(md->tio_pool); | |
1977 | if (md->io_pool) | |
1978 | mempool_destroy(md->io_pool); | |
1979 | if (md->bs) | |
1980 | bioset_free(md->bs); | |
9c47008d | 1981 | blk_integrity_unregister(md->disk); |
1da177e4 | 1982 | del_gendisk(md->disk); |
63d94e48 | 1983 | free_minor(minor); |
fba9f90e JM |
1984 | |
1985 | spin_lock(&_minor_lock); | |
1986 | md->disk->private_data = NULL; | |
1987 | spin_unlock(&_minor_lock); | |
1988 | ||
1da177e4 | 1989 | put_disk(md->disk); |
1312f40e | 1990 | blk_cleanup_queue(md->queue); |
10da4f79 | 1991 | module_put(THIS_MODULE); |
1da177e4 LT |
1992 | kfree(md); |
1993 | } | |
1994 | ||
e6ee8c0b KU |
1995 | static void __bind_mempools(struct mapped_device *md, struct dm_table *t) |
1996 | { | |
1997 | struct dm_md_mempools *p; | |
1998 | ||
1999 | if (md->io_pool && md->tio_pool && md->bs) | |
2000 | /* the md already has necessary mempools */ | |
2001 | goto out; | |
2002 | ||
2003 | p = dm_table_get_md_mempools(t); | |
2004 | BUG_ON(!p || md->io_pool || md->tio_pool || md->bs); | |
2005 | ||
2006 | md->io_pool = p->io_pool; | |
2007 | p->io_pool = NULL; | |
2008 | md->tio_pool = p->tio_pool; | |
2009 | p->tio_pool = NULL; | |
2010 | md->bs = p->bs; | |
2011 | p->bs = NULL; | |
2012 | ||
2013 | out: | |
2014 | /* mempool bind completed, now no need any mempools in the table */ | |
2015 | dm_table_free_md_mempools(t); | |
2016 | } | |
2017 | ||
1da177e4 LT |
2018 | /* |
2019 | * Bind a table to the device. | |
2020 | */ | |
2021 | static void event_callback(void *context) | |
2022 | { | |
7a8c3d3b MA |
2023 | unsigned long flags; |
2024 | LIST_HEAD(uevents); | |
1da177e4 LT |
2025 | struct mapped_device *md = (struct mapped_device *) context; |
2026 | ||
7a8c3d3b MA |
2027 | spin_lock_irqsave(&md->uevent_lock, flags); |
2028 | list_splice_init(&md->uevent_list, &uevents); | |
2029 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2030 | ||
ed9e1982 | 2031 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
7a8c3d3b | 2032 | |
1da177e4 LT |
2033 | atomic_inc(&md->event_nr); |
2034 | wake_up(&md->eventq); | |
2035 | } | |
2036 | ||
4e90188b | 2037 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 2038 | { |
4e90188b | 2039 | set_capacity(md->disk, size); |
1da177e4 | 2040 | |
db8fef4f MP |
2041 | mutex_lock(&md->bdev->bd_inode->i_mutex); |
2042 | i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); | |
2043 | mutex_unlock(&md->bdev->bd_inode->i_mutex); | |
1da177e4 LT |
2044 | } |
2045 | ||
042d2a9b AK |
2046 | /* |
2047 | * Returns old map, which caller must destroy. | |
2048 | */ | |
2049 | static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, | |
2050 | struct queue_limits *limits) | |
1da177e4 | 2051 | { |
042d2a9b | 2052 | struct dm_table *old_map; |
165125e1 | 2053 | struct request_queue *q = md->queue; |
1da177e4 | 2054 | sector_t size; |
523d9297 | 2055 | unsigned long flags; |
1da177e4 LT |
2056 | |
2057 | size = dm_table_get_size(t); | |
3ac51e74 DW |
2058 | |
2059 | /* | |
2060 | * Wipe any geometry if the size of the table changed. | |
2061 | */ | |
2062 | if (size != get_capacity(md->disk)) | |
2063 | memset(&md->geometry, 0, sizeof(md->geometry)); | |
2064 | ||
32a926da | 2065 | __set_size(md, size); |
d5816876 | 2066 | |
2ca3310e AK |
2067 | dm_table_event_callback(t, event_callback, md); |
2068 | ||
e6ee8c0b KU |
2069 | /* |
2070 | * The queue hasn't been stopped yet, if the old table type wasn't | |
2071 | * for request-based during suspension. So stop it to prevent | |
2072 | * I/O mapping before resume. | |
2073 | * This must be done before setting the queue restrictions, | |
2074 | * because request-based dm may be run just after the setting. | |
2075 | */ | |
2076 | if (dm_table_request_based(t) && !blk_queue_stopped(q)) | |
2077 | stop_queue(q); | |
2078 | ||
2079 | __bind_mempools(md, t); | |
2080 | ||
523d9297 | 2081 | write_lock_irqsave(&md->map_lock, flags); |
042d2a9b | 2082 | old_map = md->map; |
1da177e4 | 2083 | md->map = t; |
754c5fc7 | 2084 | dm_table_set_restrictions(t, q, limits); |
523d9297 | 2085 | write_unlock_irqrestore(&md->map_lock, flags); |
1da177e4 | 2086 | |
042d2a9b | 2087 | return old_map; |
1da177e4 LT |
2088 | } |
2089 | ||
a7940155 AK |
2090 | /* |
2091 | * Returns unbound table for the caller to free. | |
2092 | */ | |
2093 | static struct dm_table *__unbind(struct mapped_device *md) | |
1da177e4 LT |
2094 | { |
2095 | struct dm_table *map = md->map; | |
523d9297 | 2096 | unsigned long flags; |
1da177e4 LT |
2097 | |
2098 | if (!map) | |
a7940155 | 2099 | return NULL; |
1da177e4 LT |
2100 | |
2101 | dm_table_event_callback(map, NULL, NULL); | |
523d9297 | 2102 | write_lock_irqsave(&md->map_lock, flags); |
1da177e4 | 2103 | md->map = NULL; |
523d9297 | 2104 | write_unlock_irqrestore(&md->map_lock, flags); |
a7940155 AK |
2105 | |
2106 | return map; | |
1da177e4 LT |
2107 | } |
2108 | ||
2109 | /* | |
2110 | * Constructor for a new device. | |
2111 | */ | |
2b06cfff | 2112 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
2113 | { |
2114 | struct mapped_device *md; | |
2115 | ||
2b06cfff | 2116 | md = alloc_dev(minor); |
1da177e4 LT |
2117 | if (!md) |
2118 | return -ENXIO; | |
2119 | ||
784aae73 MB |
2120 | dm_sysfs_init(md); |
2121 | ||
1da177e4 LT |
2122 | *result = md; |
2123 | return 0; | |
2124 | } | |
2125 | ||
637842cf | 2126 | static struct mapped_device *dm_find_md(dev_t dev) |
1da177e4 LT |
2127 | { |
2128 | struct mapped_device *md; | |
1da177e4 LT |
2129 | unsigned minor = MINOR(dev); |
2130 | ||
2131 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
2132 | return NULL; | |
2133 | ||
f32c10b0 | 2134 | spin_lock(&_minor_lock); |
1da177e4 LT |
2135 | |
2136 | md = idr_find(&_minor_idr, minor); | |
fba9f90e | 2137 | if (md && (md == MINOR_ALLOCED || |
f331c029 | 2138 | (MINOR(disk_devt(dm_disk(md))) != minor) || |
17b2f66f | 2139 | test_bit(DMF_FREEING, &md->flags))) { |
637842cf | 2140 | md = NULL; |
fba9f90e JM |
2141 | goto out; |
2142 | } | |
1da177e4 | 2143 | |
fba9f90e | 2144 | out: |
f32c10b0 | 2145 | spin_unlock(&_minor_lock); |
1da177e4 | 2146 | |
637842cf DT |
2147 | return md; |
2148 | } | |
2149 | ||
d229a958 DT |
2150 | struct mapped_device *dm_get_md(dev_t dev) |
2151 | { | |
2152 | struct mapped_device *md = dm_find_md(dev); | |
2153 | ||
2154 | if (md) | |
2155 | dm_get(md); | |
2156 | ||
2157 | return md; | |
2158 | } | |
2159 | ||
9ade92a9 | 2160 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 2161 | { |
9ade92a9 | 2162 | return md->interface_ptr; |
1da177e4 LT |
2163 | } |
2164 | ||
2165 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
2166 | { | |
2167 | md->interface_ptr = ptr; | |
2168 | } | |
2169 | ||
2170 | void dm_get(struct mapped_device *md) | |
2171 | { | |
2172 | atomic_inc(&md->holders); | |
2173 | } | |
2174 | ||
72d94861 AK |
2175 | const char *dm_device_name(struct mapped_device *md) |
2176 | { | |
2177 | return md->name; | |
2178 | } | |
2179 | EXPORT_SYMBOL_GPL(dm_device_name); | |
2180 | ||
1da177e4 LT |
2181 | void dm_put(struct mapped_device *md) |
2182 | { | |
1134e5ae | 2183 | struct dm_table *map; |
1da177e4 | 2184 | |
fba9f90e JM |
2185 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
2186 | ||
f32c10b0 | 2187 | if (atomic_dec_and_lock(&md->holders, &_minor_lock)) { |
7c666411 | 2188 | map = dm_get_live_table(md); |
f331c029 TH |
2189 | idr_replace(&_minor_idr, MINOR_ALLOCED, |
2190 | MINOR(disk_devt(dm_disk(md)))); | |
fba9f90e | 2191 | set_bit(DMF_FREEING, &md->flags); |
f32c10b0 | 2192 | spin_unlock(&_minor_lock); |
4f186f8b | 2193 | if (!dm_suspended_md(md)) { |
1da177e4 LT |
2194 | dm_table_presuspend_targets(map); |
2195 | dm_table_postsuspend_targets(map); | |
2196 | } | |
784aae73 | 2197 | dm_sysfs_exit(md); |
1134e5ae | 2198 | dm_table_put(map); |
a7940155 | 2199 | dm_table_destroy(__unbind(md)); |
1da177e4 LT |
2200 | free_dev(md); |
2201 | } | |
1da177e4 | 2202 | } |
79eb885c | 2203 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 2204 | |
401600df | 2205 | static int dm_wait_for_completion(struct mapped_device *md, int interruptible) |
46125c1c MB |
2206 | { |
2207 | int r = 0; | |
b44ebeb0 MP |
2208 | DECLARE_WAITQUEUE(wait, current); |
2209 | ||
2210 | dm_unplug_all(md->queue); | |
2211 | ||
2212 | add_wait_queue(&md->wait, &wait); | |
46125c1c MB |
2213 | |
2214 | while (1) { | |
401600df | 2215 | set_current_state(interruptible); |
46125c1c MB |
2216 | |
2217 | smp_mb(); | |
b4324fee | 2218 | if (!md_in_flight(md)) |
46125c1c MB |
2219 | break; |
2220 | ||
401600df MP |
2221 | if (interruptible == TASK_INTERRUPTIBLE && |
2222 | signal_pending(current)) { | |
46125c1c MB |
2223 | r = -EINTR; |
2224 | break; | |
2225 | } | |
2226 | ||
2227 | io_schedule(); | |
2228 | } | |
2229 | set_current_state(TASK_RUNNING); | |
2230 | ||
b44ebeb0 MP |
2231 | remove_wait_queue(&md->wait, &wait); |
2232 | ||
46125c1c MB |
2233 | return r; |
2234 | } | |
2235 | ||
531fe963 | 2236 | static void dm_flush(struct mapped_device *md) |
af7e466a MP |
2237 | { |
2238 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); | |
52b1fd5a MP |
2239 | |
2240 | bio_init(&md->barrier_bio); | |
2241 | md->barrier_bio.bi_bdev = md->bdev; | |
2242 | md->barrier_bio.bi_rw = WRITE_BARRIER; | |
2243 | __split_and_process_bio(md, &md->barrier_bio); | |
2244 | ||
2245 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); | |
af7e466a MP |
2246 | } |
2247 | ||
2248 | static void process_barrier(struct mapped_device *md, struct bio *bio) | |
2249 | { | |
5aa2781d MP |
2250 | md->barrier_error = 0; |
2251 | ||
531fe963 | 2252 | dm_flush(md); |
af7e466a | 2253 | |
5aa2781d MP |
2254 | if (!bio_empty_barrier(bio)) { |
2255 | __split_and_process_bio(md, bio); | |
2256 | dm_flush(md); | |
af7e466a MP |
2257 | } |
2258 | ||
af7e466a | 2259 | if (md->barrier_error != DM_ENDIO_REQUEUE) |
531fe963 | 2260 | bio_endio(bio, md->barrier_error); |
2761e95f MP |
2261 | else { |
2262 | spin_lock_irq(&md->deferred_lock); | |
2263 | bio_list_add_head(&md->deferred, bio); | |
2264 | spin_unlock_irq(&md->deferred_lock); | |
2265 | } | |
af7e466a MP |
2266 | } |
2267 | ||
1da177e4 LT |
2268 | /* |
2269 | * Process the deferred bios | |
2270 | */ | |
ef208587 | 2271 | static void dm_wq_work(struct work_struct *work) |
1da177e4 | 2272 | { |
ef208587 MP |
2273 | struct mapped_device *md = container_of(work, struct mapped_device, |
2274 | work); | |
6d6f10df | 2275 | struct bio *c; |
1da177e4 | 2276 | |
ef208587 MP |
2277 | down_write(&md->io_lock); |
2278 | ||
3b00b203 | 2279 | while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
df12ee99 AK |
2280 | spin_lock_irq(&md->deferred_lock); |
2281 | c = bio_list_pop(&md->deferred); | |
2282 | spin_unlock_irq(&md->deferred_lock); | |
2283 | ||
2284 | if (!c) { | |
1eb787ec | 2285 | clear_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags); |
df12ee99 AK |
2286 | break; |
2287 | } | |
022c2611 | 2288 | |
3b00b203 MP |
2289 | up_write(&md->io_lock); |
2290 | ||
e6ee8c0b KU |
2291 | if (dm_request_based(md)) |
2292 | generic_make_request(c); | |
2293 | else { | |
7b6d91da | 2294 | if (c->bi_rw & REQ_HARDBARRIER) |
e6ee8c0b KU |
2295 | process_barrier(md, c); |
2296 | else | |
2297 | __split_and_process_bio(md, c); | |
2298 | } | |
3b00b203 MP |
2299 | |
2300 | down_write(&md->io_lock); | |
022c2611 | 2301 | } |
73d410c0 | 2302 | |
ef208587 | 2303 | up_write(&md->io_lock); |
1da177e4 LT |
2304 | } |
2305 | ||
9a1fb464 | 2306 | static void dm_queue_flush(struct mapped_device *md) |
304f3f6a | 2307 | { |
3b00b203 MP |
2308 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
2309 | smp_mb__after_clear_bit(); | |
53d5914f | 2310 | queue_work(md->wq, &md->work); |
304f3f6a MB |
2311 | } |
2312 | ||
d0bcb878 KU |
2313 | static void dm_rq_set_flush_nr(struct request *clone, unsigned flush_nr) |
2314 | { | |
2315 | struct dm_rq_target_io *tio = clone->end_io_data; | |
2316 | ||
2317 | tio->info.flush_request = flush_nr; | |
2318 | } | |
2319 | ||
2320 | /* Issue barrier requests to targets and wait for their completion. */ | |
2321 | static int dm_rq_barrier(struct mapped_device *md) | |
2322 | { | |
2323 | int i, j; | |
7c666411 | 2324 | struct dm_table *map = dm_get_live_table(md); |
d0bcb878 KU |
2325 | unsigned num_targets = dm_table_get_num_targets(map); |
2326 | struct dm_target *ti; | |
2327 | struct request *clone; | |
2328 | ||
2329 | md->barrier_error = 0; | |
2330 | ||
2331 | for (i = 0; i < num_targets; i++) { | |
2332 | ti = dm_table_get_target(map, i); | |
2333 | for (j = 0; j < ti->num_flush_requests; j++) { | |
2334 | clone = clone_rq(md->flush_request, md, GFP_NOIO); | |
2335 | dm_rq_set_flush_nr(clone, j); | |
2336 | atomic_inc(&md->pending[rq_data_dir(clone)]); | |
2337 | map_request(ti, clone, md); | |
2338 | } | |
2339 | } | |
2340 | ||
2341 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); | |
2342 | dm_table_put(map); | |
2343 | ||
2344 | return md->barrier_error; | |
2345 | } | |
2346 | ||
2347 | static void dm_rq_barrier_work(struct work_struct *work) | |
2348 | { | |
2349 | int error; | |
2350 | struct mapped_device *md = container_of(work, struct mapped_device, | |
2351 | barrier_work); | |
2352 | struct request_queue *q = md->queue; | |
2353 | struct request *rq; | |
2354 | unsigned long flags; | |
2355 | ||
2356 | /* | |
2357 | * Hold the md reference here and leave it at the last part so that | |
2358 | * the md can't be deleted by device opener when the barrier request | |
2359 | * completes. | |
2360 | */ | |
2361 | dm_get(md); | |
2362 | ||
2363 | error = dm_rq_barrier(md); | |
2364 | ||
2365 | rq = md->flush_request; | |
2366 | md->flush_request = NULL; | |
2367 | ||
2368 | if (error == DM_ENDIO_REQUEUE) { | |
2369 | spin_lock_irqsave(q->queue_lock, flags); | |
2370 | blk_requeue_request(q, rq); | |
2371 | spin_unlock_irqrestore(q->queue_lock, flags); | |
2372 | } else | |
2373 | blk_end_request_all(rq, error); | |
2374 | ||
2375 | blk_run_queue(q); | |
2376 | ||
2377 | dm_put(md); | |
2378 | } | |
2379 | ||
1da177e4 | 2380 | /* |
042d2a9b | 2381 | * Swap in a new table, returning the old one for the caller to destroy. |
1da177e4 | 2382 | */ |
042d2a9b | 2383 | struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) |
1da177e4 | 2384 | { |
042d2a9b | 2385 | struct dm_table *map = ERR_PTR(-EINVAL); |
754c5fc7 | 2386 | struct queue_limits limits; |
042d2a9b | 2387 | int r; |
1da177e4 | 2388 | |
e61290a4 | 2389 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
2390 | |
2391 | /* device must be suspended */ | |
4f186f8b | 2392 | if (!dm_suspended_md(md)) |
93c534ae | 2393 | goto out; |
1da177e4 | 2394 | |
754c5fc7 | 2395 | r = dm_calculate_queue_limits(table, &limits); |
042d2a9b AK |
2396 | if (r) { |
2397 | map = ERR_PTR(r); | |
754c5fc7 | 2398 | goto out; |
042d2a9b | 2399 | } |
754c5fc7 | 2400 | |
e6ee8c0b KU |
2401 | /* cannot change the device type, once a table is bound */ |
2402 | if (md->map && | |
2403 | (dm_table_get_type(md->map) != dm_table_get_type(table))) { | |
2404 | DMWARN("can't change the device type after a table is bound"); | |
2405 | goto out; | |
2406 | } | |
2407 | ||
042d2a9b | 2408 | map = __bind(md, table, &limits); |
1da177e4 | 2409 | |
93c534ae | 2410 | out: |
e61290a4 | 2411 | mutex_unlock(&md->suspend_lock); |
042d2a9b | 2412 | return map; |
1da177e4 LT |
2413 | } |
2414 | ||
2415 | /* | |
2416 | * Functions to lock and unlock any filesystem running on the | |
2417 | * device. | |
2418 | */ | |
2ca3310e | 2419 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 2420 | { |
e39e2e95 | 2421 | int r; |
1da177e4 LT |
2422 | |
2423 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 2424 | |
db8fef4f | 2425 | md->frozen_sb = freeze_bdev(md->bdev); |
dfbe03f6 | 2426 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 2427 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
2428 | md->frozen_sb = NULL; |
2429 | return r; | |
dfbe03f6 AK |
2430 | } |
2431 | ||
aa8d7c2f AK |
2432 | set_bit(DMF_FROZEN, &md->flags); |
2433 | ||
1da177e4 LT |
2434 | return 0; |
2435 | } | |
2436 | ||
2ca3310e | 2437 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 2438 | { |
aa8d7c2f AK |
2439 | if (!test_bit(DMF_FROZEN, &md->flags)) |
2440 | return; | |
2441 | ||
db8fef4f | 2442 | thaw_bdev(md->bdev, md->frozen_sb); |
1da177e4 | 2443 | md->frozen_sb = NULL; |
aa8d7c2f | 2444 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
2445 | } |
2446 | ||
2447 | /* | |
2448 | * We need to be able to change a mapping table under a mounted | |
2449 | * filesystem. For example we might want to move some data in | |
2450 | * the background. Before the table can be swapped with | |
2451 | * dm_bind_table, dm_suspend must be called to flush any in | |
2452 | * flight bios and ensure that any further io gets deferred. | |
2453 | */ | |
cec47e3d KU |
2454 | /* |
2455 | * Suspend mechanism in request-based dm. | |
2456 | * | |
9f518b27 KU |
2457 | * 1. Flush all I/Os by lock_fs() if needed. |
2458 | * 2. Stop dispatching any I/O by stopping the request_queue. | |
2459 | * 3. Wait for all in-flight I/Os to be completed or requeued. | |
cec47e3d | 2460 | * |
9f518b27 | 2461 | * To abort suspend, start the request_queue. |
cec47e3d | 2462 | */ |
a3d77d35 | 2463 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) |
1da177e4 | 2464 | { |
2ca3310e | 2465 | struct dm_table *map = NULL; |
46125c1c | 2466 | int r = 0; |
a3d77d35 | 2467 | int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0; |
2e93ccc1 | 2468 | int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0; |
1da177e4 | 2469 | |
e61290a4 | 2470 | mutex_lock(&md->suspend_lock); |
2ca3310e | 2471 | |
4f186f8b | 2472 | if (dm_suspended_md(md)) { |
73d410c0 | 2473 | r = -EINVAL; |
d287483d | 2474 | goto out_unlock; |
73d410c0 | 2475 | } |
1da177e4 | 2476 | |
7c666411 | 2477 | map = dm_get_live_table(md); |
1da177e4 | 2478 | |
2e93ccc1 KU |
2479 | /* |
2480 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
2481 | * This flag is cleared before dm_suspend returns. | |
2482 | */ | |
2483 | if (noflush) | |
2484 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
2485 | ||
cf222b37 AK |
2486 | /* This does not get reverted if there's an error later. */ |
2487 | dm_table_presuspend_targets(map); | |
2488 | ||
32a926da | 2489 | /* |
9f518b27 KU |
2490 | * Flush I/O to the device. |
2491 | * Any I/O submitted after lock_fs() may not be flushed. | |
2492 | * noflush takes precedence over do_lockfs. | |
2493 | * (lock_fs() flushes I/Os and waits for them to complete.) | |
32a926da MP |
2494 | */ |
2495 | if (!noflush && do_lockfs) { | |
2496 | r = lock_fs(md); | |
2497 | if (r) | |
f431d966 | 2498 | goto out; |
aa8d7c2f | 2499 | } |
1da177e4 LT |
2500 | |
2501 | /* | |
3b00b203 MP |
2502 | * Here we must make sure that no processes are submitting requests |
2503 | * to target drivers i.e. no one may be executing | |
2504 | * __split_and_process_bio. This is called from dm_request and | |
2505 | * dm_wq_work. | |
2506 | * | |
2507 | * To get all processes out of __split_and_process_bio in dm_request, | |
2508 | * we take the write lock. To prevent any process from reentering | |
2509 | * __split_and_process_bio from dm_request, we set | |
2510 | * DMF_QUEUE_IO_TO_THREAD. | |
2511 | * | |
2512 | * To quiesce the thread (dm_wq_work), we set DMF_BLOCK_IO_FOR_SUSPEND | |
2513 | * and call flush_workqueue(md->wq). flush_workqueue will wait until | |
2514 | * dm_wq_work exits and DMF_BLOCK_IO_FOR_SUSPEND will prevent any | |
2515 | * further calls to __split_and_process_bio from dm_wq_work. | |
1da177e4 | 2516 | */ |
2ca3310e | 2517 | down_write(&md->io_lock); |
1eb787ec AK |
2518 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
2519 | set_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags); | |
2ca3310e | 2520 | up_write(&md->io_lock); |
1da177e4 | 2521 | |
d0bcb878 KU |
2522 | /* |
2523 | * Request-based dm uses md->wq for barrier (dm_rq_barrier_work) which | |
2524 | * can be kicked until md->queue is stopped. So stop md->queue before | |
2525 | * flushing md->wq. | |
2526 | */ | |
cec47e3d | 2527 | if (dm_request_based(md)) |
9f518b27 | 2528 | stop_queue(md->queue); |
cec47e3d | 2529 | |
d0bcb878 KU |
2530 | flush_workqueue(md->wq); |
2531 | ||
1da177e4 | 2532 | /* |
3b00b203 MP |
2533 | * At this point no more requests are entering target request routines. |
2534 | * We call dm_wait_for_completion to wait for all existing requests | |
2535 | * to finish. | |
1da177e4 | 2536 | */ |
401600df | 2537 | r = dm_wait_for_completion(md, TASK_INTERRUPTIBLE); |
1da177e4 | 2538 | |
2ca3310e | 2539 | down_write(&md->io_lock); |
6d6f10df | 2540 | if (noflush) |
022c2611 | 2541 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
94d6351e | 2542 | up_write(&md->io_lock); |
2e93ccc1 | 2543 | |
1da177e4 | 2544 | /* were we interrupted ? */ |
46125c1c | 2545 | if (r < 0) { |
9a1fb464 | 2546 | dm_queue_flush(md); |
73d410c0 | 2547 | |
cec47e3d | 2548 | if (dm_request_based(md)) |
9f518b27 | 2549 | start_queue(md->queue); |
cec47e3d | 2550 | |
2ca3310e | 2551 | unlock_fs(md); |
2e93ccc1 | 2552 | goto out; /* pushback list is already flushed, so skip flush */ |
2ca3310e | 2553 | } |
1da177e4 | 2554 | |
3b00b203 MP |
2555 | /* |
2556 | * If dm_wait_for_completion returned 0, the device is completely | |
2557 | * quiescent now. There is no request-processing activity. All new | |
2558 | * requests are being added to md->deferred list. | |
2559 | */ | |
2560 | ||
2ca3310e | 2561 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 2562 | |
4d4471cb KU |
2563 | dm_table_postsuspend_targets(map); |
2564 | ||
2ca3310e AK |
2565 | out: |
2566 | dm_table_put(map); | |
d287483d AK |
2567 | |
2568 | out_unlock: | |
e61290a4 | 2569 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 2570 | return r; |
1da177e4 LT |
2571 | } |
2572 | ||
2573 | int dm_resume(struct mapped_device *md) | |
2574 | { | |
cf222b37 | 2575 | int r = -EINVAL; |
cf222b37 | 2576 | struct dm_table *map = NULL; |
1da177e4 | 2577 | |
e61290a4 | 2578 | mutex_lock(&md->suspend_lock); |
4f186f8b | 2579 | if (!dm_suspended_md(md)) |
cf222b37 | 2580 | goto out; |
cf222b37 | 2581 | |
7c666411 | 2582 | map = dm_get_live_table(md); |
2ca3310e | 2583 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 2584 | goto out; |
1da177e4 | 2585 | |
8757b776 MB |
2586 | r = dm_table_resume_targets(map); |
2587 | if (r) | |
2588 | goto out; | |
2ca3310e | 2589 | |
9a1fb464 | 2590 | dm_queue_flush(md); |
2ca3310e | 2591 | |
cec47e3d KU |
2592 | /* |
2593 | * Flushing deferred I/Os must be done after targets are resumed | |
2594 | * so that mapping of targets can work correctly. | |
2595 | * Request-based dm is queueing the deferred I/Os in its request_queue. | |
2596 | */ | |
2597 | if (dm_request_based(md)) | |
2598 | start_queue(md->queue); | |
2599 | ||
2ca3310e AK |
2600 | unlock_fs(md); |
2601 | ||
2602 | clear_bit(DMF_SUSPENDED, &md->flags); | |
2603 | ||
1da177e4 | 2604 | dm_table_unplug_all(map); |
cf222b37 AK |
2605 | r = 0; |
2606 | out: | |
2607 | dm_table_put(map); | |
e61290a4 | 2608 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 2609 | |
cf222b37 | 2610 | return r; |
1da177e4 LT |
2611 | } |
2612 | ||
2613 | /*----------------------------------------------------------------- | |
2614 | * Event notification. | |
2615 | *---------------------------------------------------------------*/ | |
3abf85b5 | 2616 | int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
60935eb2 | 2617 | unsigned cookie) |
69267a30 | 2618 | { |
60935eb2 MB |
2619 | char udev_cookie[DM_COOKIE_LENGTH]; |
2620 | char *envp[] = { udev_cookie, NULL }; | |
2621 | ||
2622 | if (!cookie) | |
3abf85b5 | 2623 | return kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
60935eb2 MB |
2624 | else { |
2625 | snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", | |
2626 | DM_COOKIE_ENV_VAR_NAME, cookie); | |
3abf85b5 PR |
2627 | return kobject_uevent_env(&disk_to_dev(md->disk)->kobj, |
2628 | action, envp); | |
60935eb2 | 2629 | } |
69267a30 AK |
2630 | } |
2631 | ||
7a8c3d3b MA |
2632 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
2633 | { | |
2634 | return atomic_add_return(1, &md->uevent_seq); | |
2635 | } | |
2636 | ||
1da177e4 LT |
2637 | uint32_t dm_get_event_nr(struct mapped_device *md) |
2638 | { | |
2639 | return atomic_read(&md->event_nr); | |
2640 | } | |
2641 | ||
2642 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
2643 | { | |
2644 | return wait_event_interruptible(md->eventq, | |
2645 | (event_nr != atomic_read(&md->event_nr))); | |
2646 | } | |
2647 | ||
7a8c3d3b MA |
2648 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
2649 | { | |
2650 | unsigned long flags; | |
2651 | ||
2652 | spin_lock_irqsave(&md->uevent_lock, flags); | |
2653 | list_add(elist, &md->uevent_list); | |
2654 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2655 | } | |
2656 | ||
1da177e4 LT |
2657 | /* |
2658 | * The gendisk is only valid as long as you have a reference | |
2659 | * count on 'md'. | |
2660 | */ | |
2661 | struct gendisk *dm_disk(struct mapped_device *md) | |
2662 | { | |
2663 | return md->disk; | |
2664 | } | |
2665 | ||
784aae73 MB |
2666 | struct kobject *dm_kobject(struct mapped_device *md) |
2667 | { | |
2668 | return &md->kobj; | |
2669 | } | |
2670 | ||
2671 | /* | |
2672 | * struct mapped_device should not be exported outside of dm.c | |
2673 | * so use this check to verify that kobj is part of md structure | |
2674 | */ | |
2675 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) | |
2676 | { | |
2677 | struct mapped_device *md; | |
2678 | ||
2679 | md = container_of(kobj, struct mapped_device, kobj); | |
2680 | if (&md->kobj != kobj) | |
2681 | return NULL; | |
2682 | ||
4d89b7b4 | 2683 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 2684 | dm_deleting_md(md)) |
4d89b7b4 MB |
2685 | return NULL; |
2686 | ||
784aae73 MB |
2687 | dm_get(md); |
2688 | return md; | |
2689 | } | |
2690 | ||
4f186f8b | 2691 | int dm_suspended_md(struct mapped_device *md) |
1da177e4 LT |
2692 | { |
2693 | return test_bit(DMF_SUSPENDED, &md->flags); | |
2694 | } | |
2695 | ||
64dbce58 KU |
2696 | int dm_suspended(struct dm_target *ti) |
2697 | { | |
ecdb2e25 | 2698 | return dm_suspended_md(dm_table_get_md(ti->table)); |
64dbce58 KU |
2699 | } |
2700 | EXPORT_SYMBOL_GPL(dm_suspended); | |
2701 | ||
2e93ccc1 KU |
2702 | int dm_noflush_suspending(struct dm_target *ti) |
2703 | { | |
ecdb2e25 | 2704 | return __noflush_suspending(dm_table_get_md(ti->table)); |
2e93ccc1 KU |
2705 | } |
2706 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
2707 | ||
e6ee8c0b KU |
2708 | struct dm_md_mempools *dm_alloc_md_mempools(unsigned type) |
2709 | { | |
2710 | struct dm_md_mempools *pools = kmalloc(sizeof(*pools), GFP_KERNEL); | |
2711 | ||
2712 | if (!pools) | |
2713 | return NULL; | |
2714 | ||
2715 | pools->io_pool = (type == DM_TYPE_BIO_BASED) ? | |
2716 | mempool_create_slab_pool(MIN_IOS, _io_cache) : | |
2717 | mempool_create_slab_pool(MIN_IOS, _rq_bio_info_cache); | |
2718 | if (!pools->io_pool) | |
2719 | goto free_pools_and_out; | |
2720 | ||
2721 | pools->tio_pool = (type == DM_TYPE_BIO_BASED) ? | |
2722 | mempool_create_slab_pool(MIN_IOS, _tio_cache) : | |
2723 | mempool_create_slab_pool(MIN_IOS, _rq_tio_cache); | |
2724 | if (!pools->tio_pool) | |
2725 | goto free_io_pool_and_out; | |
2726 | ||
2727 | pools->bs = (type == DM_TYPE_BIO_BASED) ? | |
2728 | bioset_create(16, 0) : bioset_create(MIN_IOS, 0); | |
2729 | if (!pools->bs) | |
2730 | goto free_tio_pool_and_out; | |
2731 | ||
2732 | return pools; | |
2733 | ||
2734 | free_tio_pool_and_out: | |
2735 | mempool_destroy(pools->tio_pool); | |
2736 | ||
2737 | free_io_pool_and_out: | |
2738 | mempool_destroy(pools->io_pool); | |
2739 | ||
2740 | free_pools_and_out: | |
2741 | kfree(pools); | |
2742 | ||
2743 | return NULL; | |
2744 | } | |
2745 | ||
2746 | void dm_free_md_mempools(struct dm_md_mempools *pools) | |
2747 | { | |
2748 | if (!pools) | |
2749 | return; | |
2750 | ||
2751 | if (pools->io_pool) | |
2752 | mempool_destroy(pools->io_pool); | |
2753 | ||
2754 | if (pools->tio_pool) | |
2755 | mempool_destroy(pools->tio_pool); | |
2756 | ||
2757 | if (pools->bs) | |
2758 | bioset_free(pools->bs); | |
2759 | ||
2760 | kfree(pools); | |
2761 | } | |
2762 | ||
83d5cde4 | 2763 | static const struct block_device_operations dm_blk_dops = { |
1da177e4 LT |
2764 | .open = dm_blk_open, |
2765 | .release = dm_blk_close, | |
aa129a22 | 2766 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 2767 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
2768 | .owner = THIS_MODULE |
2769 | }; | |
2770 | ||
2771 | EXPORT_SYMBOL(dm_get_mapinfo); | |
2772 | ||
2773 | /* | |
2774 | * module hooks | |
2775 | */ | |
2776 | module_init(dm_init); | |
2777 | module_exit(dm_exit); | |
2778 | ||
2779 | module_param(major, uint, 0); | |
2780 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
2781 | MODULE_DESCRIPTION(DM_NAME " driver"); | |
2782 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
2783 | MODULE_LICENSE("GPL"); |