Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. | |
784aae73 | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include "dm.h" | |
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> | |
1da177e4 LT |
17 | #include <linux/mempool.h> |
18 | #include <linux/slab.h> | |
19 | #include <linux/idr.h> | |
3ac51e74 | 20 | #include <linux/hdreg.h> |
3f77316d | 21 | #include <linux/delay.h> |
ffcc3936 | 22 | #include <linux/wait.h> |
55782138 LZ |
23 | |
24 | #include <trace/events/block.h> | |
1da177e4 | 25 | |
72d94861 AK |
26 | #define DM_MSG_PREFIX "core" |
27 | ||
71a16736 NK |
28 | #ifdef CONFIG_PRINTK |
29 | /* | |
30 | * ratelimit state to be used in DMXXX_LIMIT(). | |
31 | */ | |
32 | DEFINE_RATELIMIT_STATE(dm_ratelimit_state, | |
33 | DEFAULT_RATELIMIT_INTERVAL, | |
34 | DEFAULT_RATELIMIT_BURST); | |
35 | EXPORT_SYMBOL(dm_ratelimit_state); | |
36 | #endif | |
37 | ||
60935eb2 MB |
38 | /* |
39 | * Cookies are numeric values sent with CHANGE and REMOVE | |
40 | * uevents while resuming, removing or renaming the device. | |
41 | */ | |
42 | #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" | |
43 | #define DM_COOKIE_LENGTH 24 | |
44 | ||
1da177e4 LT |
45 | static const char *_name = DM_NAME; |
46 | ||
47 | static unsigned int major = 0; | |
48 | static unsigned int _major = 0; | |
49 | ||
d15b774c AK |
50 | static DEFINE_IDR(_minor_idr); |
51 | ||
f32c10b0 | 52 | static DEFINE_SPINLOCK(_minor_lock); |
2c140a24 MP |
53 | |
54 | static void do_deferred_remove(struct work_struct *w); | |
55 | ||
56 | static DECLARE_WORK(deferred_remove_work, do_deferred_remove); | |
57 | ||
acfe0ad7 MP |
58 | static struct workqueue_struct *deferred_remove_workqueue; |
59 | ||
1da177e4 | 60 | /* |
8fbf26ad | 61 | * For bio-based dm. |
1da177e4 LT |
62 | * One of these is allocated per bio. |
63 | */ | |
64 | struct dm_io { | |
65 | struct mapped_device *md; | |
66 | int error; | |
1da177e4 | 67 | atomic_t io_count; |
6ae2fa67 | 68 | struct bio *bio; |
3eaf840e | 69 | unsigned long start_time; |
f88fb981 | 70 | spinlock_t endio_lock; |
fd2ed4d2 | 71 | struct dm_stats_aux stats_aux; |
1da177e4 LT |
72 | }; |
73 | ||
8fbf26ad KU |
74 | /* |
75 | * For request-based dm. | |
76 | * One of these is allocated per request. | |
77 | */ | |
78 | struct dm_rq_target_io { | |
79 | struct mapped_device *md; | |
80 | struct dm_target *ti; | |
1ae49ea2 | 81 | struct request *orig, *clone; |
8fbf26ad KU |
82 | int error; |
83 | union map_info info; | |
84 | }; | |
85 | ||
86 | /* | |
94818742 KO |
87 | * For request-based dm - the bio clones we allocate are embedded in these |
88 | * structs. | |
89 | * | |
90 | * We allocate these with bio_alloc_bioset, using the front_pad parameter when | |
91 | * the bioset is created - this means the bio has to come at the end of the | |
92 | * struct. | |
8fbf26ad KU |
93 | */ |
94 | struct dm_rq_clone_bio_info { | |
95 | struct bio *orig; | |
cec47e3d | 96 | struct dm_rq_target_io *tio; |
94818742 | 97 | struct bio clone; |
8fbf26ad KU |
98 | }; |
99 | ||
cec47e3d KU |
100 | union map_info *dm_get_rq_mapinfo(struct request *rq) |
101 | { | |
102 | if (rq && rq->end_io_data) | |
103 | return &((struct dm_rq_target_io *)rq->end_io_data)->info; | |
104 | return NULL; | |
105 | } | |
106 | EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo); | |
107 | ||
ba61fdd1 JM |
108 | #define MINOR_ALLOCED ((void *)-1) |
109 | ||
1da177e4 LT |
110 | /* |
111 | * Bits for the md->flags field. | |
112 | */ | |
1eb787ec | 113 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
1da177e4 | 114 | #define DMF_SUSPENDED 1 |
aa8d7c2f | 115 | #define DMF_FROZEN 2 |
fba9f90e | 116 | #define DMF_FREEING 3 |
5c6bd75d | 117 | #define DMF_DELETING 4 |
2e93ccc1 | 118 | #define DMF_NOFLUSH_SUSPENDING 5 |
d5b9dd04 | 119 | #define DMF_MERGE_IS_OPTIONAL 6 |
2c140a24 | 120 | #define DMF_DEFERRED_REMOVE 7 |
ffcc3936 | 121 | #define DMF_SUSPENDED_INTERNALLY 8 |
1da177e4 | 122 | |
83d5e5b0 MP |
123 | /* |
124 | * A dummy definition to make RCU happy. | |
125 | * struct dm_table should never be dereferenced in this file. | |
126 | */ | |
127 | struct dm_table { | |
128 | int undefined__; | |
129 | }; | |
130 | ||
304f3f6a MB |
131 | /* |
132 | * Work processed by per-device workqueue. | |
133 | */ | |
1da177e4 | 134 | struct mapped_device { |
83d5e5b0 | 135 | struct srcu_struct io_barrier; |
e61290a4 | 136 | struct mutex suspend_lock; |
1da177e4 | 137 | atomic_t holders; |
5c6bd75d | 138 | atomic_t open_count; |
1da177e4 | 139 | |
2a7faeb1 MP |
140 | /* |
141 | * The current mapping. | |
142 | * Use dm_get_live_table{_fast} or take suspend_lock for | |
143 | * dereference. | |
144 | */ | |
6fa99520 | 145 | struct dm_table __rcu *map; |
2a7faeb1 | 146 | |
86f1152b BM |
147 | struct list_head table_devices; |
148 | struct mutex table_devices_lock; | |
149 | ||
1da177e4 LT |
150 | unsigned long flags; |
151 | ||
165125e1 | 152 | struct request_queue *queue; |
a5664dad | 153 | unsigned type; |
4a0b4ddf | 154 | /* Protect queue and type against concurrent access. */ |
a5664dad MS |
155 | struct mutex type_lock; |
156 | ||
36a0456f AK |
157 | struct target_type *immutable_target_type; |
158 | ||
1da177e4 | 159 | struct gendisk *disk; |
7e51f257 | 160 | char name[16]; |
1da177e4 LT |
161 | |
162 | void *interface_ptr; | |
163 | ||
164 | /* | |
165 | * A list of ios that arrived while we were suspended. | |
166 | */ | |
316d315b | 167 | atomic_t pending[2]; |
1da177e4 | 168 | wait_queue_head_t wait; |
53d5914f | 169 | struct work_struct work; |
74859364 | 170 | struct bio_list deferred; |
022c2611 | 171 | spinlock_t deferred_lock; |
1da177e4 | 172 | |
af7e466a | 173 | /* |
29e4013d | 174 | * Processing queue (flush) |
304f3f6a MB |
175 | */ |
176 | struct workqueue_struct *wq; | |
177 | ||
1da177e4 LT |
178 | /* |
179 | * io objects are allocated from here. | |
180 | */ | |
181 | mempool_t *io_pool; | |
1ae49ea2 | 182 | mempool_t *rq_pool; |
1da177e4 | 183 | |
9faf400f SB |
184 | struct bio_set *bs; |
185 | ||
1da177e4 LT |
186 | /* |
187 | * Event handling. | |
188 | */ | |
189 | atomic_t event_nr; | |
190 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
191 | atomic_t uevent_seq; |
192 | struct list_head uevent_list; | |
193 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
194 | |
195 | /* | |
196 | * freeze/thaw support require holding onto a super block | |
197 | */ | |
198 | struct super_block *frozen_sb; | |
db8fef4f | 199 | struct block_device *bdev; |
3ac51e74 DW |
200 | |
201 | /* forced geometry settings */ | |
202 | struct hd_geometry geometry; | |
784aae73 | 203 | |
2995fa78 MP |
204 | /* kobject and completion */ |
205 | struct dm_kobject_holder kobj_holder; | |
be35f486 | 206 | |
d87f4c14 TH |
207 | /* zero-length flush that will be cloned and submitted to targets */ |
208 | struct bio flush_bio; | |
fd2ed4d2 MP |
209 | |
210 | struct dm_stats stats; | |
1da177e4 LT |
211 | }; |
212 | ||
e6ee8c0b KU |
213 | /* |
214 | * For mempools pre-allocation at the table loading time. | |
215 | */ | |
216 | struct dm_md_mempools { | |
217 | mempool_t *io_pool; | |
1ae49ea2 | 218 | mempool_t *rq_pool; |
e6ee8c0b KU |
219 | struct bio_set *bs; |
220 | }; | |
221 | ||
86f1152b BM |
222 | struct table_device { |
223 | struct list_head list; | |
224 | atomic_t count; | |
225 | struct dm_dev dm_dev; | |
226 | }; | |
227 | ||
6cfa5857 MS |
228 | #define RESERVED_BIO_BASED_IOS 16 |
229 | #define RESERVED_REQUEST_BASED_IOS 256 | |
f4790826 | 230 | #define RESERVED_MAX_IOS 1024 |
e18b890b | 231 | static struct kmem_cache *_io_cache; |
8fbf26ad | 232 | static struct kmem_cache *_rq_tio_cache; |
1ae49ea2 | 233 | static struct kmem_cache *_rq_cache; |
94818742 | 234 | |
e8603136 MS |
235 | /* |
236 | * Bio-based DM's mempools' reserved IOs set by the user. | |
237 | */ | |
238 | static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; | |
239 | ||
f4790826 MS |
240 | /* |
241 | * Request-based DM's mempools' reserved IOs set by the user. | |
242 | */ | |
243 | static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS; | |
244 | ||
245 | static unsigned __dm_get_reserved_ios(unsigned *reserved_ios, | |
246 | unsigned def, unsigned max) | |
247 | { | |
248 | unsigned ios = ACCESS_ONCE(*reserved_ios); | |
249 | unsigned modified_ios = 0; | |
250 | ||
251 | if (!ios) | |
252 | modified_ios = def; | |
253 | else if (ios > max) | |
254 | modified_ios = max; | |
255 | ||
256 | if (modified_ios) { | |
257 | (void)cmpxchg(reserved_ios, ios, modified_ios); | |
258 | ios = modified_ios; | |
259 | } | |
260 | ||
261 | return ios; | |
262 | } | |
263 | ||
e8603136 MS |
264 | unsigned dm_get_reserved_bio_based_ios(void) |
265 | { | |
266 | return __dm_get_reserved_ios(&reserved_bio_based_ios, | |
267 | RESERVED_BIO_BASED_IOS, RESERVED_MAX_IOS); | |
268 | } | |
269 | EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); | |
270 | ||
f4790826 MS |
271 | unsigned dm_get_reserved_rq_based_ios(void) |
272 | { | |
273 | return __dm_get_reserved_ios(&reserved_rq_based_ios, | |
274 | RESERVED_REQUEST_BASED_IOS, RESERVED_MAX_IOS); | |
275 | } | |
276 | EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios); | |
277 | ||
1da177e4 LT |
278 | static int __init local_init(void) |
279 | { | |
51157b4a | 280 | int r = -ENOMEM; |
1da177e4 | 281 | |
1da177e4 | 282 | /* allocate a slab for the dm_ios */ |
028867ac | 283 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 | 284 | if (!_io_cache) |
51157b4a | 285 | return r; |
1da177e4 | 286 | |
8fbf26ad KU |
287 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
288 | if (!_rq_tio_cache) | |
dba14160 | 289 | goto out_free_io_cache; |
8fbf26ad | 290 | |
1ae49ea2 MS |
291 | _rq_cache = kmem_cache_create("dm_clone_request", sizeof(struct request), |
292 | __alignof__(struct request), 0, NULL); | |
293 | if (!_rq_cache) | |
294 | goto out_free_rq_tio_cache; | |
295 | ||
51e5b2bd | 296 | r = dm_uevent_init(); |
51157b4a | 297 | if (r) |
1ae49ea2 | 298 | goto out_free_rq_cache; |
51e5b2bd | 299 | |
acfe0ad7 MP |
300 | deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1); |
301 | if (!deferred_remove_workqueue) { | |
302 | r = -ENOMEM; | |
303 | goto out_uevent_exit; | |
304 | } | |
305 | ||
1da177e4 LT |
306 | _major = major; |
307 | r = register_blkdev(_major, _name); | |
51157b4a | 308 | if (r < 0) |
acfe0ad7 | 309 | goto out_free_workqueue; |
1da177e4 LT |
310 | |
311 | if (!_major) | |
312 | _major = r; | |
313 | ||
314 | return 0; | |
51157b4a | 315 | |
acfe0ad7 MP |
316 | out_free_workqueue: |
317 | destroy_workqueue(deferred_remove_workqueue); | |
51157b4a KU |
318 | out_uevent_exit: |
319 | dm_uevent_exit(); | |
1ae49ea2 MS |
320 | out_free_rq_cache: |
321 | kmem_cache_destroy(_rq_cache); | |
8fbf26ad KU |
322 | out_free_rq_tio_cache: |
323 | kmem_cache_destroy(_rq_tio_cache); | |
51157b4a KU |
324 | out_free_io_cache: |
325 | kmem_cache_destroy(_io_cache); | |
326 | ||
327 | return r; | |
1da177e4 LT |
328 | } |
329 | ||
330 | static void local_exit(void) | |
331 | { | |
2c140a24 | 332 | flush_scheduled_work(); |
acfe0ad7 | 333 | destroy_workqueue(deferred_remove_workqueue); |
2c140a24 | 334 | |
1ae49ea2 | 335 | kmem_cache_destroy(_rq_cache); |
8fbf26ad | 336 | kmem_cache_destroy(_rq_tio_cache); |
1da177e4 | 337 | kmem_cache_destroy(_io_cache); |
00d59405 | 338 | unregister_blkdev(_major, _name); |
51e5b2bd | 339 | dm_uevent_exit(); |
1da177e4 LT |
340 | |
341 | _major = 0; | |
342 | ||
343 | DMINFO("cleaned up"); | |
344 | } | |
345 | ||
b9249e55 | 346 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
347 | local_init, |
348 | dm_target_init, | |
349 | dm_linear_init, | |
350 | dm_stripe_init, | |
952b3557 | 351 | dm_io_init, |
945fa4d2 | 352 | dm_kcopyd_init, |
1da177e4 | 353 | dm_interface_init, |
fd2ed4d2 | 354 | dm_statistics_init, |
1da177e4 LT |
355 | }; |
356 | ||
b9249e55 | 357 | static void (*_exits[])(void) = { |
1da177e4 LT |
358 | local_exit, |
359 | dm_target_exit, | |
360 | dm_linear_exit, | |
361 | dm_stripe_exit, | |
952b3557 | 362 | dm_io_exit, |
945fa4d2 | 363 | dm_kcopyd_exit, |
1da177e4 | 364 | dm_interface_exit, |
fd2ed4d2 | 365 | dm_statistics_exit, |
1da177e4 LT |
366 | }; |
367 | ||
368 | static int __init dm_init(void) | |
369 | { | |
370 | const int count = ARRAY_SIZE(_inits); | |
371 | ||
372 | int r, i; | |
373 | ||
374 | for (i = 0; i < count; i++) { | |
375 | r = _inits[i](); | |
376 | if (r) | |
377 | goto bad; | |
378 | } | |
379 | ||
380 | return 0; | |
381 | ||
382 | bad: | |
383 | while (i--) | |
384 | _exits[i](); | |
385 | ||
386 | return r; | |
387 | } | |
388 | ||
389 | static void __exit dm_exit(void) | |
390 | { | |
391 | int i = ARRAY_SIZE(_exits); | |
392 | ||
393 | while (i--) | |
394 | _exits[i](); | |
d15b774c AK |
395 | |
396 | /* | |
397 | * Should be empty by this point. | |
398 | */ | |
d15b774c | 399 | idr_destroy(&_minor_idr); |
1da177e4 LT |
400 | } |
401 | ||
402 | /* | |
403 | * Block device functions | |
404 | */ | |
432a212c MA |
405 | int dm_deleting_md(struct mapped_device *md) |
406 | { | |
407 | return test_bit(DMF_DELETING, &md->flags); | |
408 | } | |
409 | ||
fe5f9f2c | 410 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
411 | { |
412 | struct mapped_device *md; | |
413 | ||
fba9f90e JM |
414 | spin_lock(&_minor_lock); |
415 | ||
fe5f9f2c | 416 | md = bdev->bd_disk->private_data; |
fba9f90e JM |
417 | if (!md) |
418 | goto out; | |
419 | ||
5c6bd75d | 420 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 421 | dm_deleting_md(md)) { |
fba9f90e JM |
422 | md = NULL; |
423 | goto out; | |
424 | } | |
425 | ||
1da177e4 | 426 | dm_get(md); |
5c6bd75d | 427 | atomic_inc(&md->open_count); |
fba9f90e JM |
428 | |
429 | out: | |
430 | spin_unlock(&_minor_lock); | |
431 | ||
432 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
433 | } |
434 | ||
db2a144b | 435 | static void dm_blk_close(struct gendisk *disk, fmode_t mode) |
1da177e4 | 436 | { |
fe5f9f2c | 437 | struct mapped_device *md = disk->private_data; |
6e9624b8 | 438 | |
4a1aeb98 MB |
439 | spin_lock(&_minor_lock); |
440 | ||
2c140a24 MP |
441 | if (atomic_dec_and_test(&md->open_count) && |
442 | (test_bit(DMF_DEFERRED_REMOVE, &md->flags))) | |
acfe0ad7 | 443 | queue_work(deferred_remove_workqueue, &deferred_remove_work); |
2c140a24 | 444 | |
1da177e4 | 445 | dm_put(md); |
4a1aeb98 MB |
446 | |
447 | spin_unlock(&_minor_lock); | |
1da177e4 LT |
448 | } |
449 | ||
5c6bd75d AK |
450 | int dm_open_count(struct mapped_device *md) |
451 | { | |
452 | return atomic_read(&md->open_count); | |
453 | } | |
454 | ||
455 | /* | |
456 | * Guarantees nothing is using the device before it's deleted. | |
457 | */ | |
2c140a24 | 458 | int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred) |
5c6bd75d AK |
459 | { |
460 | int r = 0; | |
461 | ||
462 | spin_lock(&_minor_lock); | |
463 | ||
2c140a24 | 464 | if (dm_open_count(md)) { |
5c6bd75d | 465 | r = -EBUSY; |
2c140a24 MP |
466 | if (mark_deferred) |
467 | set_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
468 | } else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags)) | |
469 | r = -EEXIST; | |
5c6bd75d AK |
470 | else |
471 | set_bit(DMF_DELETING, &md->flags); | |
472 | ||
473 | spin_unlock(&_minor_lock); | |
474 | ||
475 | return r; | |
476 | } | |
477 | ||
2c140a24 MP |
478 | int dm_cancel_deferred_remove(struct mapped_device *md) |
479 | { | |
480 | int r = 0; | |
481 | ||
482 | spin_lock(&_minor_lock); | |
483 | ||
484 | if (test_bit(DMF_DELETING, &md->flags)) | |
485 | r = -EBUSY; | |
486 | else | |
487 | clear_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
488 | ||
489 | spin_unlock(&_minor_lock); | |
490 | ||
491 | return r; | |
492 | } | |
493 | ||
494 | static void do_deferred_remove(struct work_struct *w) | |
495 | { | |
496 | dm_deferred_remove(); | |
497 | } | |
498 | ||
fd2ed4d2 MP |
499 | sector_t dm_get_size(struct mapped_device *md) |
500 | { | |
501 | return get_capacity(md->disk); | |
502 | } | |
503 | ||
9974fa2c MS |
504 | struct request_queue *dm_get_md_queue(struct mapped_device *md) |
505 | { | |
506 | return md->queue; | |
507 | } | |
508 | ||
fd2ed4d2 MP |
509 | struct dm_stats *dm_get_stats(struct mapped_device *md) |
510 | { | |
511 | return &md->stats; | |
512 | } | |
513 | ||
3ac51e74 DW |
514 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
515 | { | |
516 | struct mapped_device *md = bdev->bd_disk->private_data; | |
517 | ||
518 | return dm_get_geometry(md, geo); | |
519 | } | |
520 | ||
fe5f9f2c | 521 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
aa129a22 MB |
522 | unsigned int cmd, unsigned long arg) |
523 | { | |
fe5f9f2c | 524 | struct mapped_device *md = bdev->bd_disk->private_data; |
83d5e5b0 | 525 | int srcu_idx; |
6c182cd8 | 526 | struct dm_table *map; |
aa129a22 MB |
527 | struct dm_target *tgt; |
528 | int r = -ENOTTY; | |
529 | ||
6c182cd8 | 530 | retry: |
83d5e5b0 MP |
531 | map = dm_get_live_table(md, &srcu_idx); |
532 | ||
aa129a22 MB |
533 | if (!map || !dm_table_get_size(map)) |
534 | goto out; | |
535 | ||
536 | /* We only support devices that have a single target */ | |
537 | if (dm_table_get_num_targets(map) != 1) | |
538 | goto out; | |
539 | ||
540 | tgt = dm_table_get_target(map, 0); | |
4d341d82 MS |
541 | if (!tgt->type->ioctl) |
542 | goto out; | |
aa129a22 | 543 | |
4f186f8b | 544 | if (dm_suspended_md(md)) { |
aa129a22 MB |
545 | r = -EAGAIN; |
546 | goto out; | |
547 | } | |
548 | ||
4d341d82 | 549 | r = tgt->type->ioctl(tgt, cmd, arg); |
aa129a22 MB |
550 | |
551 | out: | |
83d5e5b0 | 552 | dm_put_live_table(md, srcu_idx); |
aa129a22 | 553 | |
6c182cd8 HR |
554 | if (r == -ENOTCONN) { |
555 | msleep(10); | |
556 | goto retry; | |
557 | } | |
558 | ||
aa129a22 MB |
559 | return r; |
560 | } | |
561 | ||
028867ac | 562 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
563 | { |
564 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
565 | } | |
566 | ||
028867ac | 567 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
568 | { |
569 | mempool_free(io, md->io_pool); | |
570 | } | |
571 | ||
028867ac | 572 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 | 573 | { |
dba14160 | 574 | bio_put(&tio->clone); |
1da177e4 LT |
575 | } |
576 | ||
08885643 KU |
577 | static struct dm_rq_target_io *alloc_rq_tio(struct mapped_device *md, |
578 | gfp_t gfp_mask) | |
cec47e3d | 579 | { |
5f015204 | 580 | return mempool_alloc(md->io_pool, gfp_mask); |
cec47e3d KU |
581 | } |
582 | ||
583 | static void free_rq_tio(struct dm_rq_target_io *tio) | |
584 | { | |
5f015204 | 585 | mempool_free(tio, tio->md->io_pool); |
cec47e3d KU |
586 | } |
587 | ||
1ae49ea2 MS |
588 | static struct request *alloc_clone_request(struct mapped_device *md, |
589 | gfp_t gfp_mask) | |
590 | { | |
591 | return mempool_alloc(md->rq_pool, gfp_mask); | |
592 | } | |
593 | ||
594 | static void free_clone_request(struct mapped_device *md, struct request *rq) | |
595 | { | |
596 | mempool_free(rq, md->rq_pool); | |
597 | } | |
598 | ||
90abb8c4 KU |
599 | static int md_in_flight(struct mapped_device *md) |
600 | { | |
601 | return atomic_read(&md->pending[READ]) + | |
602 | atomic_read(&md->pending[WRITE]); | |
603 | } | |
604 | ||
3eaf840e JNN |
605 | static void start_io_acct(struct dm_io *io) |
606 | { | |
607 | struct mapped_device *md = io->md; | |
fd2ed4d2 | 608 | struct bio *bio = io->bio; |
c9959059 | 609 | int cpu; |
fd2ed4d2 | 610 | int rw = bio_data_dir(bio); |
3eaf840e JNN |
611 | |
612 | io->start_time = jiffies; | |
613 | ||
074a7aca TH |
614 | cpu = part_stat_lock(); |
615 | part_round_stats(cpu, &dm_disk(md)->part0); | |
616 | part_stat_unlock(); | |
1e9bb880 SL |
617 | atomic_set(&dm_disk(md)->part0.in_flight[rw], |
618 | atomic_inc_return(&md->pending[rw])); | |
fd2ed4d2 MP |
619 | |
620 | if (unlikely(dm_stats_used(&md->stats))) | |
4f024f37 | 621 | dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, |
fd2ed4d2 | 622 | bio_sectors(bio), false, 0, &io->stats_aux); |
3eaf840e JNN |
623 | } |
624 | ||
d221d2e7 | 625 | static void end_io_acct(struct dm_io *io) |
3eaf840e JNN |
626 | { |
627 | struct mapped_device *md = io->md; | |
628 | struct bio *bio = io->bio; | |
629 | unsigned long duration = jiffies - io->start_time; | |
18c0b223 | 630 | int pending; |
3eaf840e JNN |
631 | int rw = bio_data_dir(bio); |
632 | ||
18c0b223 | 633 | generic_end_io_acct(rw, &dm_disk(md)->part0, io->start_time); |
3eaf840e | 634 | |
fd2ed4d2 | 635 | if (unlikely(dm_stats_used(&md->stats))) |
4f024f37 | 636 | dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, |
fd2ed4d2 MP |
637 | bio_sectors(bio), true, duration, &io->stats_aux); |
638 | ||
af7e466a MP |
639 | /* |
640 | * After this is decremented the bio must not be touched if it is | |
d87f4c14 | 641 | * a flush. |
af7e466a | 642 | */ |
1e9bb880 SL |
643 | pending = atomic_dec_return(&md->pending[rw]); |
644 | atomic_set(&dm_disk(md)->part0.in_flight[rw], pending); | |
316d315b | 645 | pending += atomic_read(&md->pending[rw^0x1]); |
3eaf840e | 646 | |
d221d2e7 MP |
647 | /* nudge anyone waiting on suspend queue */ |
648 | if (!pending) | |
649 | wake_up(&md->wait); | |
3eaf840e JNN |
650 | } |
651 | ||
1da177e4 LT |
652 | /* |
653 | * Add the bio to the list of deferred io. | |
654 | */ | |
92c63902 | 655 | static void queue_io(struct mapped_device *md, struct bio *bio) |
1da177e4 | 656 | { |
05447420 | 657 | unsigned long flags; |
1da177e4 | 658 | |
05447420 | 659 | spin_lock_irqsave(&md->deferred_lock, flags); |
1da177e4 | 660 | bio_list_add(&md->deferred, bio); |
05447420 | 661 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
6a8736d1 | 662 | queue_work(md->wq, &md->work); |
1da177e4 LT |
663 | } |
664 | ||
665 | /* | |
666 | * Everyone (including functions in this file), should use this | |
667 | * function to access the md->map field, and make sure they call | |
83d5e5b0 | 668 | * dm_put_live_table() when finished. |
1da177e4 | 669 | */ |
83d5e5b0 | 670 | struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier) |
1da177e4 | 671 | { |
83d5e5b0 MP |
672 | *srcu_idx = srcu_read_lock(&md->io_barrier); |
673 | ||
674 | return srcu_dereference(md->map, &md->io_barrier); | |
675 | } | |
1da177e4 | 676 | |
83d5e5b0 MP |
677 | void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier) |
678 | { | |
679 | srcu_read_unlock(&md->io_barrier, srcu_idx); | |
680 | } | |
681 | ||
682 | void dm_sync_table(struct mapped_device *md) | |
683 | { | |
684 | synchronize_srcu(&md->io_barrier); | |
685 | synchronize_rcu_expedited(); | |
686 | } | |
687 | ||
688 | /* | |
689 | * A fast alternative to dm_get_live_table/dm_put_live_table. | |
690 | * The caller must not block between these two functions. | |
691 | */ | |
692 | static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU) | |
693 | { | |
694 | rcu_read_lock(); | |
695 | return rcu_dereference(md->map); | |
696 | } | |
1da177e4 | 697 | |
83d5e5b0 MP |
698 | static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU) |
699 | { | |
700 | rcu_read_unlock(); | |
1da177e4 LT |
701 | } |
702 | ||
86f1152b BM |
703 | /* |
704 | * Open a table device so we can use it as a map destination. | |
705 | */ | |
706 | static int open_table_device(struct table_device *td, dev_t dev, | |
707 | struct mapped_device *md) | |
708 | { | |
709 | static char *_claim_ptr = "I belong to device-mapper"; | |
710 | struct block_device *bdev; | |
711 | ||
712 | int r; | |
713 | ||
714 | BUG_ON(td->dm_dev.bdev); | |
715 | ||
716 | bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _claim_ptr); | |
717 | if (IS_ERR(bdev)) | |
718 | return PTR_ERR(bdev); | |
719 | ||
720 | r = bd_link_disk_holder(bdev, dm_disk(md)); | |
721 | if (r) { | |
722 | blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL); | |
723 | return r; | |
724 | } | |
725 | ||
726 | td->dm_dev.bdev = bdev; | |
727 | return 0; | |
728 | } | |
729 | ||
730 | /* | |
731 | * Close a table device that we've been using. | |
732 | */ | |
733 | static void close_table_device(struct table_device *td, struct mapped_device *md) | |
734 | { | |
735 | if (!td->dm_dev.bdev) | |
736 | return; | |
737 | ||
738 | bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md)); | |
739 | blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL); | |
740 | td->dm_dev.bdev = NULL; | |
741 | } | |
742 | ||
743 | static struct table_device *find_table_device(struct list_head *l, dev_t dev, | |
744 | fmode_t mode) { | |
745 | struct table_device *td; | |
746 | ||
747 | list_for_each_entry(td, l, list) | |
748 | if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode) | |
749 | return td; | |
750 | ||
751 | return NULL; | |
752 | } | |
753 | ||
754 | int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, | |
755 | struct dm_dev **result) { | |
756 | int r; | |
757 | struct table_device *td; | |
758 | ||
759 | mutex_lock(&md->table_devices_lock); | |
760 | td = find_table_device(&md->table_devices, dev, mode); | |
761 | if (!td) { | |
762 | td = kmalloc(sizeof(*td), GFP_KERNEL); | |
763 | if (!td) { | |
764 | mutex_unlock(&md->table_devices_lock); | |
765 | return -ENOMEM; | |
766 | } | |
767 | ||
768 | td->dm_dev.mode = mode; | |
769 | td->dm_dev.bdev = NULL; | |
770 | ||
771 | if ((r = open_table_device(td, dev, md))) { | |
772 | mutex_unlock(&md->table_devices_lock); | |
773 | kfree(td); | |
774 | return r; | |
775 | } | |
776 | ||
777 | format_dev_t(td->dm_dev.name, dev); | |
778 | ||
779 | atomic_set(&td->count, 0); | |
780 | list_add(&td->list, &md->table_devices); | |
781 | } | |
782 | atomic_inc(&td->count); | |
783 | mutex_unlock(&md->table_devices_lock); | |
784 | ||
785 | *result = &td->dm_dev; | |
786 | return 0; | |
787 | } | |
788 | EXPORT_SYMBOL_GPL(dm_get_table_device); | |
789 | ||
790 | void dm_put_table_device(struct mapped_device *md, struct dm_dev *d) | |
791 | { | |
792 | struct table_device *td = container_of(d, struct table_device, dm_dev); | |
793 | ||
794 | mutex_lock(&md->table_devices_lock); | |
795 | if (atomic_dec_and_test(&td->count)) { | |
796 | close_table_device(td, md); | |
797 | list_del(&td->list); | |
798 | kfree(td); | |
799 | } | |
800 | mutex_unlock(&md->table_devices_lock); | |
801 | } | |
802 | EXPORT_SYMBOL(dm_put_table_device); | |
803 | ||
804 | static void free_table_devices(struct list_head *devices) | |
805 | { | |
806 | struct list_head *tmp, *next; | |
807 | ||
808 | list_for_each_safe(tmp, next, devices) { | |
809 | struct table_device *td = list_entry(tmp, struct table_device, list); | |
810 | ||
811 | DMWARN("dm_destroy: %s still exists with %d references", | |
812 | td->dm_dev.name, atomic_read(&td->count)); | |
813 | kfree(td); | |
814 | } | |
815 | } | |
816 | ||
3ac51e74 DW |
817 | /* |
818 | * Get the geometry associated with a dm device | |
819 | */ | |
820 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
821 | { | |
822 | *geo = md->geometry; | |
823 | ||
824 | return 0; | |
825 | } | |
826 | ||
827 | /* | |
828 | * Set the geometry of a device. | |
829 | */ | |
830 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
831 | { | |
832 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
833 | ||
834 | if (geo->start > sz) { | |
835 | DMWARN("Start sector is beyond the geometry limits."); | |
836 | return -EINVAL; | |
837 | } | |
838 | ||
839 | md->geometry = *geo; | |
840 | ||
841 | return 0; | |
842 | } | |
843 | ||
1da177e4 LT |
844 | /*----------------------------------------------------------------- |
845 | * CRUD START: | |
846 | * A more elegant soln is in the works that uses the queue | |
847 | * merge fn, unfortunately there are a couple of changes to | |
848 | * the block layer that I want to make for this. So in the | |
849 | * interests of getting something for people to use I give | |
850 | * you this clearly demarcated crap. | |
851 | *---------------------------------------------------------------*/ | |
852 | ||
2e93ccc1 KU |
853 | static int __noflush_suspending(struct mapped_device *md) |
854 | { | |
855 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
856 | } | |
857 | ||
1da177e4 LT |
858 | /* |
859 | * Decrements the number of outstanding ios that a bio has been | |
860 | * cloned into, completing the original io if necc. | |
861 | */ | |
858119e1 | 862 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 863 | { |
2e93ccc1 | 864 | unsigned long flags; |
b35f8caa MB |
865 | int io_error; |
866 | struct bio *bio; | |
867 | struct mapped_device *md = io->md; | |
2e93ccc1 KU |
868 | |
869 | /* Push-back supersedes any I/O errors */ | |
f88fb981 KU |
870 | if (unlikely(error)) { |
871 | spin_lock_irqsave(&io->endio_lock, flags); | |
872 | if (!(io->error > 0 && __noflush_suspending(md))) | |
873 | io->error = error; | |
874 | spin_unlock_irqrestore(&io->endio_lock, flags); | |
875 | } | |
1da177e4 LT |
876 | |
877 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
878 | if (io->error == DM_ENDIO_REQUEUE) { |
879 | /* | |
880 | * Target requested pushing back the I/O. | |
2e93ccc1 | 881 | */ |
022c2611 | 882 | spin_lock_irqsave(&md->deferred_lock, flags); |
6a8736d1 TH |
883 | if (__noflush_suspending(md)) |
884 | bio_list_add_head(&md->deferred, io->bio); | |
885 | else | |
2e93ccc1 KU |
886 | /* noflush suspend was interrupted. */ |
887 | io->error = -EIO; | |
022c2611 | 888 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
2e93ccc1 KU |
889 | } |
890 | ||
b35f8caa MB |
891 | io_error = io->error; |
892 | bio = io->bio; | |
6a8736d1 TH |
893 | end_io_acct(io); |
894 | free_io(md, io); | |
895 | ||
896 | if (io_error == DM_ENDIO_REQUEUE) | |
897 | return; | |
2e93ccc1 | 898 | |
4f024f37 | 899 | if ((bio->bi_rw & REQ_FLUSH) && bio->bi_iter.bi_size) { |
af7e466a | 900 | /* |
6a8736d1 TH |
901 | * Preflush done for flush with data, reissue |
902 | * without REQ_FLUSH. | |
af7e466a | 903 | */ |
6a8736d1 TH |
904 | bio->bi_rw &= ~REQ_FLUSH; |
905 | queue_io(md, bio); | |
af7e466a | 906 | } else { |
b372d360 | 907 | /* done with normal IO or empty flush */ |
0a82a8d1 | 908 | trace_block_bio_complete(md->queue, bio, io_error); |
b372d360 | 909 | bio_endio(bio, io_error); |
b35f8caa | 910 | } |
1da177e4 LT |
911 | } |
912 | } | |
913 | ||
7eee4ae2 MS |
914 | static void disable_write_same(struct mapped_device *md) |
915 | { | |
916 | struct queue_limits *limits = dm_get_queue_limits(md); | |
917 | ||
918 | /* device doesn't really support WRITE SAME, disable it */ | |
919 | limits->max_write_same_sectors = 0; | |
920 | } | |
921 | ||
6712ecf8 | 922 | static void clone_endio(struct bio *bio, int error) |
1da177e4 | 923 | { |
5164bece | 924 | int r = error; |
bfc6d41c | 925 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
b35f8caa | 926 | struct dm_io *io = tio->io; |
9faf400f | 927 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
928 | dm_endio_fn endio = tio->ti->type->end_io; |
929 | ||
1da177e4 LT |
930 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
931 | error = -EIO; | |
932 | ||
933 | if (endio) { | |
7de3ee57 | 934 | r = endio(tio->ti, bio, error); |
2e93ccc1 KU |
935 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
936 | /* | |
937 | * error and requeue request are handled | |
938 | * in dec_pending(). | |
939 | */ | |
1da177e4 | 940 | error = r; |
45cbcd79 KU |
941 | else if (r == DM_ENDIO_INCOMPLETE) |
942 | /* The target will handle the io */ | |
6712ecf8 | 943 | return; |
45cbcd79 KU |
944 | else if (r) { |
945 | DMWARN("unimplemented target endio return value: %d", r); | |
946 | BUG(); | |
947 | } | |
1da177e4 LT |
948 | } |
949 | ||
7eee4ae2 MS |
950 | if (unlikely(r == -EREMOTEIO && (bio->bi_rw & REQ_WRITE_SAME) && |
951 | !bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors)) | |
952 | disable_write_same(md); | |
953 | ||
9faf400f | 954 | free_tio(md, tio); |
b35f8caa | 955 | dec_pending(io, error); |
1da177e4 LT |
956 | } |
957 | ||
cec47e3d KU |
958 | /* |
959 | * Partial completion handling for request-based dm | |
960 | */ | |
961 | static void end_clone_bio(struct bio *clone, int error) | |
962 | { | |
bfc6d41c MP |
963 | struct dm_rq_clone_bio_info *info = |
964 | container_of(clone, struct dm_rq_clone_bio_info, clone); | |
cec47e3d KU |
965 | struct dm_rq_target_io *tio = info->tio; |
966 | struct bio *bio = info->orig; | |
4f024f37 | 967 | unsigned int nr_bytes = info->orig->bi_iter.bi_size; |
cec47e3d KU |
968 | |
969 | bio_put(clone); | |
970 | ||
971 | if (tio->error) | |
972 | /* | |
973 | * An error has already been detected on the request. | |
974 | * Once error occurred, just let clone->end_io() handle | |
975 | * the remainder. | |
976 | */ | |
977 | return; | |
978 | else if (error) { | |
979 | /* | |
980 | * Don't notice the error to the upper layer yet. | |
981 | * The error handling decision is made by the target driver, | |
982 | * when the request is completed. | |
983 | */ | |
984 | tio->error = error; | |
985 | return; | |
986 | } | |
987 | ||
988 | /* | |
989 | * I/O for the bio successfully completed. | |
990 | * Notice the data completion to the upper layer. | |
991 | */ | |
992 | ||
993 | /* | |
994 | * bios are processed from the head of the list. | |
995 | * So the completing bio should always be rq->bio. | |
996 | * If it's not, something wrong is happening. | |
997 | */ | |
998 | if (tio->orig->bio != bio) | |
999 | DMERR("bio completion is going in the middle of the request"); | |
1000 | ||
1001 | /* | |
1002 | * Update the original request. | |
1003 | * Do not use blk_end_request() here, because it may complete | |
1004 | * the original request before the clone, and break the ordering. | |
1005 | */ | |
1006 | blk_update_request(tio->orig, 0, nr_bytes); | |
1007 | } | |
1008 | ||
1009 | /* | |
1010 | * Don't touch any member of the md after calling this function because | |
1011 | * the md may be freed in dm_put() at the end of this function. | |
1012 | * Or do dm_get() before calling this function and dm_put() later. | |
1013 | */ | |
b4324fee | 1014 | static void rq_completed(struct mapped_device *md, int rw, int run_queue) |
cec47e3d | 1015 | { |
b4324fee | 1016 | atomic_dec(&md->pending[rw]); |
cec47e3d KU |
1017 | |
1018 | /* nudge anyone waiting on suspend queue */ | |
b4324fee | 1019 | if (!md_in_flight(md)) |
cec47e3d KU |
1020 | wake_up(&md->wait); |
1021 | ||
a8c32a5c JA |
1022 | /* |
1023 | * Run this off this callpath, as drivers could invoke end_io while | |
1024 | * inside their request_fn (and holding the queue lock). Calling | |
1025 | * back into ->request_fn() could deadlock attempting to grab the | |
1026 | * queue lock again. | |
1027 | */ | |
cec47e3d | 1028 | if (run_queue) |
a8c32a5c | 1029 | blk_run_queue_async(md->queue); |
cec47e3d KU |
1030 | |
1031 | /* | |
1032 | * dm_put() must be at the end of this function. See the comment above | |
1033 | */ | |
1034 | dm_put(md); | |
1035 | } | |
1036 | ||
a77e28c7 KU |
1037 | static void free_rq_clone(struct request *clone) |
1038 | { | |
1039 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1040 | ||
1041 | blk_rq_unprep_clone(clone); | |
1ae49ea2 | 1042 | free_clone_request(tio->md, clone); |
a77e28c7 KU |
1043 | free_rq_tio(tio); |
1044 | } | |
1045 | ||
980691e5 KU |
1046 | /* |
1047 | * Complete the clone and the original request. | |
1048 | * Must be called without queue lock. | |
1049 | */ | |
1050 | static void dm_end_request(struct request *clone, int error) | |
1051 | { | |
1052 | int rw = rq_data_dir(clone); | |
1053 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1054 | struct mapped_device *md = tio->md; | |
1055 | struct request *rq = tio->orig; | |
1056 | ||
29e4013d | 1057 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
980691e5 KU |
1058 | rq->errors = clone->errors; |
1059 | rq->resid_len = clone->resid_len; | |
1060 | ||
1061 | if (rq->sense) | |
1062 | /* | |
1063 | * We are using the sense buffer of the original | |
1064 | * request. | |
1065 | * So setting the length of the sense data is enough. | |
1066 | */ | |
1067 | rq->sense_len = clone->sense_len; | |
1068 | } | |
1069 | ||
1070 | free_rq_clone(clone); | |
29e4013d TH |
1071 | blk_end_request_all(rq, error); |
1072 | rq_completed(md, rw, true); | |
980691e5 KU |
1073 | } |
1074 | ||
cec47e3d KU |
1075 | static void dm_unprep_request(struct request *rq) |
1076 | { | |
1077 | struct request *clone = rq->special; | |
cec47e3d KU |
1078 | |
1079 | rq->special = NULL; | |
1080 | rq->cmd_flags &= ~REQ_DONTPREP; | |
1081 | ||
a77e28c7 | 1082 | free_rq_clone(clone); |
cec47e3d KU |
1083 | } |
1084 | ||
1085 | /* | |
1086 | * Requeue the original request of a clone. | |
1087 | */ | |
dbf9782c | 1088 | static void dm_requeue_unmapped_request(struct request *clone) |
cec47e3d | 1089 | { |
b4324fee | 1090 | int rw = rq_data_dir(clone); |
cec47e3d KU |
1091 | struct dm_rq_target_io *tio = clone->end_io_data; |
1092 | struct mapped_device *md = tio->md; | |
1093 | struct request *rq = tio->orig; | |
1094 | struct request_queue *q = rq->q; | |
1095 | unsigned long flags; | |
1096 | ||
1097 | dm_unprep_request(rq); | |
1098 | ||
1099 | spin_lock_irqsave(q->queue_lock, flags); | |
cec47e3d KU |
1100 | blk_requeue_request(q, rq); |
1101 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1102 | ||
b4324fee | 1103 | rq_completed(md, rw, 0); |
cec47e3d | 1104 | } |
cec47e3d KU |
1105 | |
1106 | static void __stop_queue(struct request_queue *q) | |
1107 | { | |
1108 | blk_stop_queue(q); | |
1109 | } | |
1110 | ||
1111 | static void stop_queue(struct request_queue *q) | |
1112 | { | |
1113 | unsigned long flags; | |
1114 | ||
1115 | spin_lock_irqsave(q->queue_lock, flags); | |
1116 | __stop_queue(q); | |
1117 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1118 | } | |
1119 | ||
1120 | static void __start_queue(struct request_queue *q) | |
1121 | { | |
1122 | if (blk_queue_stopped(q)) | |
1123 | blk_start_queue(q); | |
1124 | } | |
1125 | ||
1126 | static void start_queue(struct request_queue *q) | |
1127 | { | |
1128 | unsigned long flags; | |
1129 | ||
1130 | spin_lock_irqsave(q->queue_lock, flags); | |
1131 | __start_queue(q); | |
1132 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1133 | } | |
1134 | ||
11a68244 | 1135 | static void dm_done(struct request *clone, int error, bool mapped) |
cec47e3d | 1136 | { |
11a68244 | 1137 | int r = error; |
cec47e3d | 1138 | struct dm_rq_target_io *tio = clone->end_io_data; |
ba1cbad9 | 1139 | dm_request_endio_fn rq_end_io = NULL; |
cec47e3d | 1140 | |
ba1cbad9 MS |
1141 | if (tio->ti) { |
1142 | rq_end_io = tio->ti->type->rq_end_io; | |
1143 | ||
1144 | if (mapped && rq_end_io) | |
1145 | r = rq_end_io(tio->ti, clone, error, &tio->info); | |
1146 | } | |
cec47e3d | 1147 | |
7eee4ae2 MS |
1148 | if (unlikely(r == -EREMOTEIO && (clone->cmd_flags & REQ_WRITE_SAME) && |
1149 | !clone->q->limits.max_write_same_sectors)) | |
1150 | disable_write_same(tio->md); | |
1151 | ||
11a68244 | 1152 | if (r <= 0) |
cec47e3d | 1153 | /* The target wants to complete the I/O */ |
11a68244 KU |
1154 | dm_end_request(clone, r); |
1155 | else if (r == DM_ENDIO_INCOMPLETE) | |
cec47e3d KU |
1156 | /* The target will handle the I/O */ |
1157 | return; | |
11a68244 | 1158 | else if (r == DM_ENDIO_REQUEUE) |
cec47e3d KU |
1159 | /* The target wants to requeue the I/O */ |
1160 | dm_requeue_unmapped_request(clone); | |
1161 | else { | |
11a68244 | 1162 | DMWARN("unimplemented target endio return value: %d", r); |
cec47e3d KU |
1163 | BUG(); |
1164 | } | |
1165 | } | |
1166 | ||
11a68244 KU |
1167 | /* |
1168 | * Request completion handler for request-based dm | |
1169 | */ | |
1170 | static void dm_softirq_done(struct request *rq) | |
1171 | { | |
1172 | bool mapped = true; | |
1173 | struct request *clone = rq->completion_data; | |
1174 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1175 | ||
1176 | if (rq->cmd_flags & REQ_FAILED) | |
1177 | mapped = false; | |
1178 | ||
1179 | dm_done(clone, tio->error, mapped); | |
1180 | } | |
1181 | ||
cec47e3d KU |
1182 | /* |
1183 | * Complete the clone and the original request with the error status | |
1184 | * through softirq context. | |
1185 | */ | |
1186 | static void dm_complete_request(struct request *clone, int error) | |
1187 | { | |
1188 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1189 | struct request *rq = tio->orig; | |
1190 | ||
1191 | tio->error = error; | |
1192 | rq->completion_data = clone; | |
1193 | blk_complete_request(rq); | |
1194 | } | |
1195 | ||
1196 | /* | |
1197 | * Complete the not-mapped clone and the original request with the error status | |
1198 | * through softirq context. | |
1199 | * Target's rq_end_io() function isn't called. | |
1200 | * This may be used when the target's map_rq() function fails. | |
1201 | */ | |
dbf9782c | 1202 | static void dm_kill_unmapped_request(struct request *clone, int error) |
cec47e3d KU |
1203 | { |
1204 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1205 | struct request *rq = tio->orig; | |
1206 | ||
1207 | rq->cmd_flags |= REQ_FAILED; | |
1208 | dm_complete_request(clone, error); | |
1209 | } | |
cec47e3d KU |
1210 | |
1211 | /* | |
1212 | * Called with the queue lock held | |
1213 | */ | |
1214 | static void end_clone_request(struct request *clone, int error) | |
1215 | { | |
1216 | /* | |
1217 | * For just cleaning up the information of the queue in which | |
1218 | * the clone was dispatched. | |
1219 | * The clone is *NOT* freed actually here because it is alloced from | |
1220 | * dm own mempool and REQ_ALLOCED isn't set in clone->cmd_flags. | |
1221 | */ | |
1222 | __blk_put_request(clone->q, clone); | |
1223 | ||
1224 | /* | |
1225 | * Actual request completion is done in a softirq context which doesn't | |
1226 | * hold the queue lock. Otherwise, deadlock could occur because: | |
1227 | * - another request may be submitted by the upper level driver | |
1228 | * of the stacking during the completion | |
1229 | * - the submission which requires queue lock may be done | |
1230 | * against this queue | |
1231 | */ | |
1232 | dm_complete_request(clone, error); | |
1233 | } | |
1234 | ||
56a67df7 MS |
1235 | /* |
1236 | * Return maximum size of I/O possible at the supplied sector up to the current | |
1237 | * target boundary. | |
1238 | */ | |
1239 | static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti) | |
1240 | { | |
1241 | sector_t target_offset = dm_target_offset(ti, sector); | |
1242 | ||
1243 | return ti->len - target_offset; | |
1244 | } | |
1245 | ||
1246 | static sector_t max_io_len(sector_t sector, struct dm_target *ti) | |
1da177e4 | 1247 | { |
56a67df7 | 1248 | sector_t len = max_io_len_target_boundary(sector, ti); |
542f9038 | 1249 | sector_t offset, max_len; |
1da177e4 LT |
1250 | |
1251 | /* | |
542f9038 | 1252 | * Does the target need to split even further? |
1da177e4 | 1253 | */ |
542f9038 MS |
1254 | if (ti->max_io_len) { |
1255 | offset = dm_target_offset(ti, sector); | |
1256 | if (unlikely(ti->max_io_len & (ti->max_io_len - 1))) | |
1257 | max_len = sector_div(offset, ti->max_io_len); | |
1258 | else | |
1259 | max_len = offset & (ti->max_io_len - 1); | |
1260 | max_len = ti->max_io_len - max_len; | |
1261 | ||
1262 | if (len > max_len) | |
1263 | len = max_len; | |
1da177e4 LT |
1264 | } |
1265 | ||
1266 | return len; | |
1267 | } | |
1268 | ||
542f9038 MS |
1269 | int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) |
1270 | { | |
1271 | if (len > UINT_MAX) { | |
1272 | DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)", | |
1273 | (unsigned long long)len, UINT_MAX); | |
1274 | ti->error = "Maximum size of target IO is too large"; | |
1275 | return -EINVAL; | |
1276 | } | |
1277 | ||
1278 | ti->max_io_len = (uint32_t) len; | |
1279 | ||
1280 | return 0; | |
1281 | } | |
1282 | EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); | |
1283 | ||
1dd40c3e MP |
1284 | /* |
1285 | * A target may call dm_accept_partial_bio only from the map routine. It is | |
1286 | * allowed for all bio types except REQ_FLUSH. | |
1287 | * | |
1288 | * dm_accept_partial_bio informs the dm that the target only wants to process | |
1289 | * additional n_sectors sectors of the bio and the rest of the data should be | |
1290 | * sent in a next bio. | |
1291 | * | |
1292 | * A diagram that explains the arithmetics: | |
1293 | * +--------------------+---------------+-------+ | |
1294 | * | 1 | 2 | 3 | | |
1295 | * +--------------------+---------------+-------+ | |
1296 | * | |
1297 | * <-------------- *tio->len_ptr ---------------> | |
1298 | * <------- bi_size -------> | |
1299 | * <-- n_sectors --> | |
1300 | * | |
1301 | * Region 1 was already iterated over with bio_advance or similar function. | |
1302 | * (it may be empty if the target doesn't use bio_advance) | |
1303 | * Region 2 is the remaining bio size that the target wants to process. | |
1304 | * (it may be empty if region 1 is non-empty, although there is no reason | |
1305 | * to make it empty) | |
1306 | * The target requires that region 3 is to be sent in the next bio. | |
1307 | * | |
1308 | * If the target wants to receive multiple copies of the bio (via num_*bios, etc), | |
1309 | * the partially processed part (the sum of regions 1+2) must be the same for all | |
1310 | * copies of the bio. | |
1311 | */ | |
1312 | void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) | |
1313 | { | |
1314 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); | |
1315 | unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; | |
1316 | BUG_ON(bio->bi_rw & REQ_FLUSH); | |
1317 | BUG_ON(bi_size > *tio->len_ptr); | |
1318 | BUG_ON(n_sectors > bi_size); | |
1319 | *tio->len_ptr -= bi_size - n_sectors; | |
1320 | bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT; | |
1321 | } | |
1322 | EXPORT_SYMBOL_GPL(dm_accept_partial_bio); | |
1323 | ||
bd2a49b8 | 1324 | static void __map_bio(struct dm_target_io *tio) |
1da177e4 LT |
1325 | { |
1326 | int r; | |
2056a782 | 1327 | sector_t sector; |
9faf400f | 1328 | struct mapped_device *md; |
dba14160 | 1329 | struct bio *clone = &tio->clone; |
bd2a49b8 | 1330 | struct dm_target *ti = tio->ti; |
1da177e4 | 1331 | |
1da177e4 | 1332 | clone->bi_end_io = clone_endio; |
1da177e4 LT |
1333 | |
1334 | /* | |
1335 | * Map the clone. If r == 0 we don't need to do | |
1336 | * anything, the target has assumed ownership of | |
1337 | * this io. | |
1338 | */ | |
1339 | atomic_inc(&tio->io->io_count); | |
4f024f37 | 1340 | sector = clone->bi_iter.bi_sector; |
7de3ee57 | 1341 | r = ti->type->map(ti, clone); |
45cbcd79 | 1342 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 1343 | /* the bio has been remapped so dispatch it */ |
2056a782 | 1344 | |
d07335e5 MS |
1345 | trace_block_bio_remap(bdev_get_queue(clone->bi_bdev), clone, |
1346 | tio->io->bio->bi_bdev->bd_dev, sector); | |
2056a782 | 1347 | |
1da177e4 | 1348 | generic_make_request(clone); |
2e93ccc1 KU |
1349 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
1350 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
1351 | md = tio->io->md; |
1352 | dec_pending(tio->io, r); | |
9faf400f | 1353 | free_tio(md, tio); |
45cbcd79 KU |
1354 | } else if (r) { |
1355 | DMWARN("unimplemented target map return value: %d", r); | |
1356 | BUG(); | |
1da177e4 LT |
1357 | } |
1358 | } | |
1359 | ||
1360 | struct clone_info { | |
1361 | struct mapped_device *md; | |
1362 | struct dm_table *map; | |
1363 | struct bio *bio; | |
1364 | struct dm_io *io; | |
1365 | sector_t sector; | |
e0d6609a | 1366 | unsigned sector_count; |
1da177e4 LT |
1367 | }; |
1368 | ||
e0d6609a | 1369 | static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) |
bd2a49b8 | 1370 | { |
4f024f37 KO |
1371 | bio->bi_iter.bi_sector = sector; |
1372 | bio->bi_iter.bi_size = to_bytes(len); | |
1da177e4 LT |
1373 | } |
1374 | ||
1375 | /* | |
1376 | * Creates a bio that consists of range of complete bvecs. | |
1377 | */ | |
dba14160 | 1378 | static void clone_bio(struct dm_target_io *tio, struct bio *bio, |
1c3b13e6 | 1379 | sector_t sector, unsigned len) |
1da177e4 | 1380 | { |
dba14160 | 1381 | struct bio *clone = &tio->clone; |
1da177e4 | 1382 | |
1c3b13e6 KO |
1383 | __bio_clone_fast(clone, bio); |
1384 | ||
1385 | if (bio_integrity(bio)) | |
1386 | bio_integrity_clone(clone, bio, GFP_NOIO); | |
bd2a49b8 | 1387 | |
1c3b13e6 KO |
1388 | bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); |
1389 | clone->bi_iter.bi_size = to_bytes(len); | |
1390 | ||
1391 | if (bio_integrity(bio)) | |
1392 | bio_integrity_trim(clone, 0, len); | |
1da177e4 LT |
1393 | } |
1394 | ||
9015df24 | 1395 | static struct dm_target_io *alloc_tio(struct clone_info *ci, |
99778273 | 1396 | struct dm_target *ti, |
55a62eef | 1397 | unsigned target_bio_nr) |
f9ab94ce | 1398 | { |
dba14160 MP |
1399 | struct dm_target_io *tio; |
1400 | struct bio *clone; | |
1401 | ||
99778273 | 1402 | clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs); |
dba14160 | 1403 | tio = container_of(clone, struct dm_target_io, clone); |
f9ab94ce MP |
1404 | |
1405 | tio->io = ci->io; | |
1406 | tio->ti = ti; | |
55a62eef | 1407 | tio->target_bio_nr = target_bio_nr; |
9015df24 AK |
1408 | |
1409 | return tio; | |
1410 | } | |
1411 | ||
14fe594d AK |
1412 | static void __clone_and_map_simple_bio(struct clone_info *ci, |
1413 | struct dm_target *ti, | |
1dd40c3e | 1414 | unsigned target_bio_nr, unsigned *len) |
9015df24 | 1415 | { |
99778273 | 1416 | struct dm_target_io *tio = alloc_tio(ci, ti, target_bio_nr); |
dba14160 | 1417 | struct bio *clone = &tio->clone; |
9015df24 | 1418 | |
1dd40c3e MP |
1419 | tio->len_ptr = len; |
1420 | ||
99778273 | 1421 | __bio_clone_fast(clone, ci->bio); |
bd2a49b8 | 1422 | if (len) |
1dd40c3e | 1423 | bio_setup_sector(clone, ci->sector, *len); |
f9ab94ce | 1424 | |
bd2a49b8 | 1425 | __map_bio(tio); |
f9ab94ce MP |
1426 | } |
1427 | ||
14fe594d | 1428 | static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, |
1dd40c3e | 1429 | unsigned num_bios, unsigned *len) |
06a426ce | 1430 | { |
55a62eef | 1431 | unsigned target_bio_nr; |
06a426ce | 1432 | |
55a62eef | 1433 | for (target_bio_nr = 0; target_bio_nr < num_bios; target_bio_nr++) |
14fe594d | 1434 | __clone_and_map_simple_bio(ci, ti, target_bio_nr, len); |
06a426ce MS |
1435 | } |
1436 | ||
14fe594d | 1437 | static int __send_empty_flush(struct clone_info *ci) |
f9ab94ce | 1438 | { |
06a426ce | 1439 | unsigned target_nr = 0; |
f9ab94ce MP |
1440 | struct dm_target *ti; |
1441 | ||
b372d360 | 1442 | BUG_ON(bio_has_data(ci->bio)); |
f9ab94ce | 1443 | while ((ti = dm_table_get_target(ci->map, target_nr++))) |
1dd40c3e | 1444 | __send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL); |
f9ab94ce | 1445 | |
f9ab94ce MP |
1446 | return 0; |
1447 | } | |
1448 | ||
e4c93811 | 1449 | static void __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, |
1dd40c3e | 1450 | sector_t sector, unsigned *len) |
5ae89a87 | 1451 | { |
dba14160 | 1452 | struct bio *bio = ci->bio; |
5ae89a87 | 1453 | struct dm_target_io *tio; |
b0d8ed4d AK |
1454 | unsigned target_bio_nr; |
1455 | unsigned num_target_bios = 1; | |
5ae89a87 | 1456 | |
b0d8ed4d AK |
1457 | /* |
1458 | * Does the target want to receive duplicate copies of the bio? | |
1459 | */ | |
1460 | if (bio_data_dir(bio) == WRITE && ti->num_write_bios) | |
1461 | num_target_bios = ti->num_write_bios(ti, bio); | |
e4c93811 | 1462 | |
b0d8ed4d | 1463 | for (target_bio_nr = 0; target_bio_nr < num_target_bios; target_bio_nr++) { |
99778273 | 1464 | tio = alloc_tio(ci, ti, target_bio_nr); |
1dd40c3e MP |
1465 | tio->len_ptr = len; |
1466 | clone_bio(tio, bio, sector, *len); | |
b0d8ed4d AK |
1467 | __map_bio(tio); |
1468 | } | |
5ae89a87 MS |
1469 | } |
1470 | ||
55a62eef | 1471 | typedef unsigned (*get_num_bios_fn)(struct dm_target *ti); |
23508a96 | 1472 | |
55a62eef | 1473 | static unsigned get_num_discard_bios(struct dm_target *ti) |
23508a96 | 1474 | { |
55a62eef | 1475 | return ti->num_discard_bios; |
23508a96 MS |
1476 | } |
1477 | ||
55a62eef | 1478 | static unsigned get_num_write_same_bios(struct dm_target *ti) |
23508a96 | 1479 | { |
55a62eef | 1480 | return ti->num_write_same_bios; |
23508a96 MS |
1481 | } |
1482 | ||
1483 | typedef bool (*is_split_required_fn)(struct dm_target *ti); | |
1484 | ||
1485 | static bool is_split_required_for_discard(struct dm_target *ti) | |
1486 | { | |
55a62eef | 1487 | return ti->split_discard_bios; |
23508a96 MS |
1488 | } |
1489 | ||
14fe594d AK |
1490 | static int __send_changing_extent_only(struct clone_info *ci, |
1491 | get_num_bios_fn get_num_bios, | |
1492 | is_split_required_fn is_split_required) | |
5ae89a87 MS |
1493 | { |
1494 | struct dm_target *ti; | |
e0d6609a | 1495 | unsigned len; |
55a62eef | 1496 | unsigned num_bios; |
5ae89a87 | 1497 | |
a79245b3 MS |
1498 | do { |
1499 | ti = dm_table_find_target(ci->map, ci->sector); | |
1500 | if (!dm_target_is_valid(ti)) | |
1501 | return -EIO; | |
5ae89a87 | 1502 | |
5ae89a87 | 1503 | /* |
23508a96 MS |
1504 | * Even though the device advertised support for this type of |
1505 | * request, that does not mean every target supports it, and | |
936688d7 | 1506 | * reconfiguration might also have changed that since the |
a79245b3 | 1507 | * check was performed. |
5ae89a87 | 1508 | */ |
55a62eef AK |
1509 | num_bios = get_num_bios ? get_num_bios(ti) : 0; |
1510 | if (!num_bios) | |
a79245b3 | 1511 | return -EOPNOTSUPP; |
5ae89a87 | 1512 | |
23508a96 | 1513 | if (is_split_required && !is_split_required(ti)) |
e0d6609a | 1514 | len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); |
7acf0277 | 1515 | else |
e0d6609a | 1516 | len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti)); |
06a426ce | 1517 | |
1dd40c3e | 1518 | __send_duplicate_bios(ci, ti, num_bios, &len); |
a79245b3 MS |
1519 | |
1520 | ci->sector += len; | |
1521 | } while (ci->sector_count -= len); | |
5ae89a87 MS |
1522 | |
1523 | return 0; | |
1524 | } | |
1525 | ||
14fe594d | 1526 | static int __send_discard(struct clone_info *ci) |
23508a96 | 1527 | { |
14fe594d AK |
1528 | return __send_changing_extent_only(ci, get_num_discard_bios, |
1529 | is_split_required_for_discard); | |
23508a96 MS |
1530 | } |
1531 | ||
14fe594d | 1532 | static int __send_write_same(struct clone_info *ci) |
23508a96 | 1533 | { |
14fe594d | 1534 | return __send_changing_extent_only(ci, get_num_write_same_bios, NULL); |
23508a96 MS |
1535 | } |
1536 | ||
e4c93811 AK |
1537 | /* |
1538 | * Select the correct strategy for processing a non-flush bio. | |
1539 | */ | |
14fe594d | 1540 | static int __split_and_process_non_flush(struct clone_info *ci) |
1da177e4 | 1541 | { |
dba14160 | 1542 | struct bio *bio = ci->bio; |
512875bd | 1543 | struct dm_target *ti; |
1c3b13e6 | 1544 | unsigned len; |
1da177e4 | 1545 | |
5ae89a87 | 1546 | if (unlikely(bio->bi_rw & REQ_DISCARD)) |
14fe594d | 1547 | return __send_discard(ci); |
23508a96 | 1548 | else if (unlikely(bio->bi_rw & REQ_WRITE_SAME)) |
14fe594d | 1549 | return __send_write_same(ci); |
5ae89a87 | 1550 | |
512875bd JN |
1551 | ti = dm_table_find_target(ci->map, ci->sector); |
1552 | if (!dm_target_is_valid(ti)) | |
1553 | return -EIO; | |
1554 | ||
1c3b13e6 | 1555 | len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count); |
1da177e4 | 1556 | |
1dd40c3e | 1557 | __clone_and_map_data_bio(ci, ti, ci->sector, &len); |
1da177e4 | 1558 | |
1c3b13e6 KO |
1559 | ci->sector += len; |
1560 | ci->sector_count -= len; | |
1da177e4 | 1561 | |
1c3b13e6 | 1562 | return 0; |
1da177e4 LT |
1563 | } |
1564 | ||
1565 | /* | |
14fe594d | 1566 | * Entry point to split a bio into clones and submit them to the targets. |
1da177e4 | 1567 | */ |
83d5e5b0 MP |
1568 | static void __split_and_process_bio(struct mapped_device *md, |
1569 | struct dm_table *map, struct bio *bio) | |
1da177e4 LT |
1570 | { |
1571 | struct clone_info ci; | |
512875bd | 1572 | int error = 0; |
1da177e4 | 1573 | |
83d5e5b0 | 1574 | if (unlikely(!map)) { |
6a8736d1 | 1575 | bio_io_error(bio); |
f0b9a450 MP |
1576 | return; |
1577 | } | |
692d0eb9 | 1578 | |
83d5e5b0 | 1579 | ci.map = map; |
1da177e4 | 1580 | ci.md = md; |
1da177e4 LT |
1581 | ci.io = alloc_io(md); |
1582 | ci.io->error = 0; | |
1583 | atomic_set(&ci.io->io_count, 1); | |
1584 | ci.io->bio = bio; | |
1585 | ci.io->md = md; | |
f88fb981 | 1586 | spin_lock_init(&ci.io->endio_lock); |
4f024f37 | 1587 | ci.sector = bio->bi_iter.bi_sector; |
1da177e4 | 1588 | |
3eaf840e | 1589 | start_io_acct(ci.io); |
bd2a49b8 | 1590 | |
b372d360 MS |
1591 | if (bio->bi_rw & REQ_FLUSH) { |
1592 | ci.bio = &ci.md->flush_bio; | |
1593 | ci.sector_count = 0; | |
14fe594d | 1594 | error = __send_empty_flush(&ci); |
b372d360 MS |
1595 | /* dec_pending submits any data associated with flush */ |
1596 | } else { | |
6a8736d1 | 1597 | ci.bio = bio; |
d87f4c14 | 1598 | ci.sector_count = bio_sectors(bio); |
b372d360 | 1599 | while (ci.sector_count && !error) |
14fe594d | 1600 | error = __split_and_process_non_flush(&ci); |
d87f4c14 | 1601 | } |
1da177e4 LT |
1602 | |
1603 | /* drop the extra reference count */ | |
512875bd | 1604 | dec_pending(ci.io, error); |
1da177e4 LT |
1605 | } |
1606 | /*----------------------------------------------------------------- | |
1607 | * CRUD END | |
1608 | *---------------------------------------------------------------*/ | |
1609 | ||
f6fccb12 MB |
1610 | static int dm_merge_bvec(struct request_queue *q, |
1611 | struct bvec_merge_data *bvm, | |
1612 | struct bio_vec *biovec) | |
1613 | { | |
1614 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 | 1615 | struct dm_table *map = dm_get_live_table_fast(md); |
f6fccb12 MB |
1616 | struct dm_target *ti; |
1617 | sector_t max_sectors; | |
5037108a | 1618 | int max_size = 0; |
f6fccb12 MB |
1619 | |
1620 | if (unlikely(!map)) | |
5037108a | 1621 | goto out; |
f6fccb12 MB |
1622 | |
1623 | ti = dm_table_find_target(map, bvm->bi_sector); | |
b01cd5ac | 1624 | if (!dm_target_is_valid(ti)) |
83d5e5b0 | 1625 | goto out; |
f6fccb12 MB |
1626 | |
1627 | /* | |
1628 | * Find maximum amount of I/O that won't need splitting | |
1629 | */ | |
56a67df7 | 1630 | max_sectors = min(max_io_len(bvm->bi_sector, ti), |
148e51ba | 1631 | (sector_t) queue_max_sectors(q)); |
f6fccb12 | 1632 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; |
148e51ba | 1633 | if (unlikely(max_size < 0)) /* this shouldn't _ever_ happen */ |
f6fccb12 MB |
1634 | max_size = 0; |
1635 | ||
1636 | /* | |
1637 | * merge_bvec_fn() returns number of bytes | |
1638 | * it can accept at this offset | |
1639 | * max is precomputed maximal io size | |
1640 | */ | |
1641 | if (max_size && ti->type->merge) | |
1642 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
8cbeb67a MP |
1643 | /* |
1644 | * If the target doesn't support merge method and some of the devices | |
148e51ba MS |
1645 | * provided their merge_bvec method (we know this by looking for the |
1646 | * max_hw_sectors that dm_set_device_limits may set), then we can't | |
1647 | * allow bios with multiple vector entries. So always set max_size | |
1648 | * to 0, and the code below allows just one page. | |
8cbeb67a MP |
1649 | */ |
1650 | else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9) | |
8cbeb67a | 1651 | max_size = 0; |
f6fccb12 | 1652 | |
5037108a | 1653 | out: |
83d5e5b0 | 1654 | dm_put_live_table_fast(md); |
f6fccb12 MB |
1655 | /* |
1656 | * Always allow an entire first page | |
1657 | */ | |
1658 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
1659 | max_size = biovec->bv_len; | |
1660 | ||
f6fccb12 MB |
1661 | return max_size; |
1662 | } | |
1663 | ||
1da177e4 LT |
1664 | /* |
1665 | * The request function that just remaps the bio built up by | |
1666 | * dm_merge_bvec. | |
1667 | */ | |
5a7bbad2 | 1668 | static void _dm_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 1669 | { |
12f03a49 | 1670 | int rw = bio_data_dir(bio); |
1da177e4 | 1671 | struct mapped_device *md = q->queuedata; |
83d5e5b0 MP |
1672 | int srcu_idx; |
1673 | struct dm_table *map; | |
1da177e4 | 1674 | |
83d5e5b0 | 1675 | map = dm_get_live_table(md, &srcu_idx); |
1da177e4 | 1676 | |
18c0b223 | 1677 | generic_start_io_acct(rw, bio_sectors(bio), &dm_disk(md)->part0); |
12f03a49 | 1678 | |
6a8736d1 TH |
1679 | /* if we're suspended, we have to queue this io for later */ |
1680 | if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { | |
83d5e5b0 | 1681 | dm_put_live_table(md, srcu_idx); |
1da177e4 | 1682 | |
6a8736d1 TH |
1683 | if (bio_rw(bio) != READA) |
1684 | queue_io(md, bio); | |
1685 | else | |
54d9a1b4 | 1686 | bio_io_error(bio); |
5a7bbad2 | 1687 | return; |
1da177e4 LT |
1688 | } |
1689 | ||
83d5e5b0 MP |
1690 | __split_and_process_bio(md, map, bio); |
1691 | dm_put_live_table(md, srcu_idx); | |
5a7bbad2 | 1692 | return; |
cec47e3d KU |
1693 | } |
1694 | ||
fd2ed4d2 | 1695 | int dm_request_based(struct mapped_device *md) |
cec47e3d KU |
1696 | { |
1697 | return blk_queue_stackable(md->queue); | |
1698 | } | |
1699 | ||
5a7bbad2 | 1700 | static void dm_request(struct request_queue *q, struct bio *bio) |
cec47e3d KU |
1701 | { |
1702 | struct mapped_device *md = q->queuedata; | |
1703 | ||
1704 | if (dm_request_based(md)) | |
5a7bbad2 CH |
1705 | blk_queue_bio(q, bio); |
1706 | else | |
1707 | _dm_request(q, bio); | |
cec47e3d KU |
1708 | } |
1709 | ||
dbf9782c | 1710 | static void dm_dispatch_request(struct request *rq) |
cec47e3d KU |
1711 | { |
1712 | int r; | |
1713 | ||
1714 | if (blk_queue_io_stat(rq->q)) | |
1715 | rq->cmd_flags |= REQ_IO_STAT; | |
1716 | ||
1717 | rq->start_time = jiffies; | |
1718 | r = blk_insert_cloned_request(rq->q, rq); | |
1719 | if (r) | |
1720 | dm_complete_request(rq, r); | |
1721 | } | |
cec47e3d | 1722 | |
cec47e3d KU |
1723 | static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig, |
1724 | void *data) | |
1725 | { | |
1726 | struct dm_rq_target_io *tio = data; | |
94818742 KO |
1727 | struct dm_rq_clone_bio_info *info = |
1728 | container_of(bio, struct dm_rq_clone_bio_info, clone); | |
cec47e3d KU |
1729 | |
1730 | info->orig = bio_orig; | |
1731 | info->tio = tio; | |
1732 | bio->bi_end_io = end_clone_bio; | |
cec47e3d KU |
1733 | |
1734 | return 0; | |
1735 | } | |
1736 | ||
1737 | static int setup_clone(struct request *clone, struct request *rq, | |
1ae49ea2 | 1738 | struct dm_rq_target_io *tio, gfp_t gfp_mask) |
cec47e3d | 1739 | { |
d0bcb878 | 1740 | int r; |
cec47e3d | 1741 | |
1ae49ea2 | 1742 | r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask, |
29e4013d TH |
1743 | dm_rq_bio_constructor, tio); |
1744 | if (r) | |
1745 | return r; | |
cec47e3d | 1746 | |
29e4013d TH |
1747 | clone->cmd = rq->cmd; |
1748 | clone->cmd_len = rq->cmd_len; | |
1749 | clone->sense = rq->sense; | |
cec47e3d KU |
1750 | clone->end_io = end_clone_request; |
1751 | clone->end_io_data = tio; | |
1752 | ||
1ae49ea2 MS |
1753 | tio->clone = clone; |
1754 | ||
cec47e3d KU |
1755 | return 0; |
1756 | } | |
1757 | ||
1ae49ea2 MS |
1758 | static struct request *__clone_rq(struct request *rq, struct mapped_device *md, |
1759 | struct dm_rq_target_io *tio, gfp_t gfp_mask) | |
1760 | { | |
1761 | struct request *clone = alloc_clone_request(md, gfp_mask); | |
1762 | ||
1763 | if (!clone) | |
1764 | return NULL; | |
1765 | ||
1766 | blk_rq_init(NULL, clone); | |
1767 | if (setup_clone(clone, rq, tio, gfp_mask)) { | |
1768 | /* -ENOMEM */ | |
1769 | free_clone_request(md, clone); | |
1770 | return NULL; | |
1771 | } | |
1772 | ||
1773 | return clone; | |
1774 | } | |
1775 | ||
6facdaff KU |
1776 | static struct request *clone_rq(struct request *rq, struct mapped_device *md, |
1777 | gfp_t gfp_mask) | |
1778 | { | |
1779 | struct request *clone; | |
1780 | struct dm_rq_target_io *tio; | |
1781 | ||
1782 | tio = alloc_rq_tio(md, gfp_mask); | |
1783 | if (!tio) | |
1784 | return NULL; | |
1785 | ||
1786 | tio->md = md; | |
1787 | tio->ti = NULL; | |
1ae49ea2 | 1788 | tio->clone = NULL; |
6facdaff KU |
1789 | tio->orig = rq; |
1790 | tio->error = 0; | |
1791 | memset(&tio->info, 0, sizeof(tio->info)); | |
1792 | ||
1ae49ea2 MS |
1793 | clone = __clone_rq(rq, md, tio, GFP_ATOMIC); |
1794 | if (!clone) { | |
6facdaff KU |
1795 | free_rq_tio(tio); |
1796 | return NULL; | |
1797 | } | |
1798 | ||
1799 | return clone; | |
1800 | } | |
1801 | ||
cec47e3d KU |
1802 | /* |
1803 | * Called with the queue lock held. | |
1804 | */ | |
1805 | static int dm_prep_fn(struct request_queue *q, struct request *rq) | |
1806 | { | |
1807 | struct mapped_device *md = q->queuedata; | |
cec47e3d KU |
1808 | struct request *clone; |
1809 | ||
cec47e3d KU |
1810 | if (unlikely(rq->special)) { |
1811 | DMWARN("Already has something in rq->special."); | |
1812 | return BLKPREP_KILL; | |
1813 | } | |
1814 | ||
6facdaff KU |
1815 | clone = clone_rq(rq, md, GFP_ATOMIC); |
1816 | if (!clone) | |
cec47e3d | 1817 | return BLKPREP_DEFER; |
cec47e3d KU |
1818 | |
1819 | rq->special = clone; | |
1820 | rq->cmd_flags |= REQ_DONTPREP; | |
1821 | ||
1822 | return BLKPREP_OK; | |
1823 | } | |
1824 | ||
9eef87da KU |
1825 | /* |
1826 | * Returns: | |
1827 | * 0 : the request has been processed (not requeued) | |
1828 | * !0 : the request has been requeued | |
1829 | */ | |
1830 | static int map_request(struct dm_target *ti, struct request *clone, | |
1831 | struct mapped_device *md) | |
cec47e3d | 1832 | { |
9eef87da | 1833 | int r, requeued = 0; |
cec47e3d KU |
1834 | struct dm_rq_target_io *tio = clone->end_io_data; |
1835 | ||
cec47e3d KU |
1836 | tio->ti = ti; |
1837 | r = ti->type->map_rq(ti, clone, &tio->info); | |
1838 | switch (r) { | |
1839 | case DM_MAPIO_SUBMITTED: | |
1840 | /* The target has taken the I/O to submit by itself later */ | |
1841 | break; | |
1842 | case DM_MAPIO_REMAPPED: | |
1843 | /* The target has remapped the I/O so dispatch it */ | |
6db4ccd6 JN |
1844 | trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)), |
1845 | blk_rq_pos(tio->orig)); | |
cec47e3d KU |
1846 | dm_dispatch_request(clone); |
1847 | break; | |
1848 | case DM_MAPIO_REQUEUE: | |
1849 | /* The target wants to requeue the I/O */ | |
1850 | dm_requeue_unmapped_request(clone); | |
9eef87da | 1851 | requeued = 1; |
cec47e3d KU |
1852 | break; |
1853 | default: | |
1854 | if (r > 0) { | |
1855 | DMWARN("unimplemented target map return value: %d", r); | |
1856 | BUG(); | |
1857 | } | |
1858 | ||
1859 | /* The target wants to complete the I/O */ | |
1860 | dm_kill_unmapped_request(clone, r); | |
1861 | break; | |
1862 | } | |
9eef87da KU |
1863 | |
1864 | return requeued; | |
cec47e3d KU |
1865 | } |
1866 | ||
ba1cbad9 MS |
1867 | static struct request *dm_start_request(struct mapped_device *md, struct request *orig) |
1868 | { | |
1869 | struct request *clone; | |
1870 | ||
1871 | blk_start_request(orig); | |
1872 | clone = orig->special; | |
1873 | atomic_inc(&md->pending[rq_data_dir(clone)]); | |
1874 | ||
1875 | /* | |
1876 | * Hold the md reference here for the in-flight I/O. | |
1877 | * We can't rely on the reference count by device opener, | |
1878 | * because the device may be closed during the request completion | |
1879 | * when all bios are completed. | |
1880 | * See the comment in rq_completed() too. | |
1881 | */ | |
1882 | dm_get(md); | |
1883 | ||
1884 | return clone; | |
1885 | } | |
1886 | ||
cec47e3d KU |
1887 | /* |
1888 | * q->request_fn for request-based dm. | |
1889 | * Called with the queue lock held. | |
1890 | */ | |
1891 | static void dm_request_fn(struct request_queue *q) | |
1892 | { | |
1893 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 MP |
1894 | int srcu_idx; |
1895 | struct dm_table *map = dm_get_live_table(md, &srcu_idx); | |
cec47e3d | 1896 | struct dm_target *ti; |
b4324fee | 1897 | struct request *rq, *clone; |
29e4013d | 1898 | sector_t pos; |
cec47e3d KU |
1899 | |
1900 | /* | |
b4324fee KU |
1901 | * For suspend, check blk_queue_stopped() and increment |
1902 | * ->pending within a single queue_lock not to increment the | |
1903 | * number of in-flight I/Os after the queue is stopped in | |
1904 | * dm_suspend(). | |
cec47e3d | 1905 | */ |
7eaceacc | 1906 | while (!blk_queue_stopped(q)) { |
cec47e3d KU |
1907 | rq = blk_peek_request(q); |
1908 | if (!rq) | |
7eaceacc | 1909 | goto delay_and_out; |
cec47e3d | 1910 | |
29e4013d TH |
1911 | /* always use block 0 to find the target for flushes for now */ |
1912 | pos = 0; | |
1913 | if (!(rq->cmd_flags & REQ_FLUSH)) | |
1914 | pos = blk_rq_pos(rq); | |
1915 | ||
1916 | ti = dm_table_find_target(map, pos); | |
ba1cbad9 MS |
1917 | if (!dm_target_is_valid(ti)) { |
1918 | /* | |
1919 | * Must perform setup, that dm_done() requires, | |
1920 | * before calling dm_kill_unmapped_request | |
1921 | */ | |
1922 | DMERR_LIMIT("request attempted access beyond the end of device"); | |
1923 | clone = dm_start_request(md, rq); | |
1924 | dm_kill_unmapped_request(clone, -EIO); | |
1925 | continue; | |
1926 | } | |
d0bcb878 | 1927 | |
cec47e3d | 1928 | if (ti->type->busy && ti->type->busy(ti)) |
7eaceacc | 1929 | goto delay_and_out; |
cec47e3d | 1930 | |
ba1cbad9 | 1931 | clone = dm_start_request(md, rq); |
b4324fee | 1932 | |
cec47e3d | 1933 | spin_unlock(q->queue_lock); |
9eef87da KU |
1934 | if (map_request(ti, clone, md)) |
1935 | goto requeued; | |
1936 | ||
052189a2 KU |
1937 | BUG_ON(!irqs_disabled()); |
1938 | spin_lock(q->queue_lock); | |
cec47e3d KU |
1939 | } |
1940 | ||
1941 | goto out; | |
1942 | ||
9eef87da | 1943 | requeued: |
052189a2 KU |
1944 | BUG_ON(!irqs_disabled()); |
1945 | spin_lock(q->queue_lock); | |
9eef87da | 1946 | |
7eaceacc JA |
1947 | delay_and_out: |
1948 | blk_delay_queue(q, HZ / 10); | |
cec47e3d | 1949 | out: |
83d5e5b0 | 1950 | dm_put_live_table(md, srcu_idx); |
cec47e3d KU |
1951 | } |
1952 | ||
1953 | int dm_underlying_device_busy(struct request_queue *q) | |
1954 | { | |
1955 | return blk_lld_busy(q); | |
1956 | } | |
1957 | EXPORT_SYMBOL_GPL(dm_underlying_device_busy); | |
1958 | ||
1959 | static int dm_lld_busy(struct request_queue *q) | |
1960 | { | |
1961 | int r; | |
1962 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 | 1963 | struct dm_table *map = dm_get_live_table_fast(md); |
cec47e3d KU |
1964 | |
1965 | if (!map || test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) | |
1966 | r = 1; | |
1967 | else | |
1968 | r = dm_table_any_busy_target(map); | |
1969 | ||
83d5e5b0 | 1970 | dm_put_live_table_fast(md); |
cec47e3d KU |
1971 | |
1972 | return r; | |
1973 | } | |
1974 | ||
1da177e4 LT |
1975 | static int dm_any_congested(void *congested_data, int bdi_bits) |
1976 | { | |
8a57dfc6 CS |
1977 | int r = bdi_bits; |
1978 | struct mapped_device *md = congested_data; | |
1979 | struct dm_table *map; | |
1da177e4 | 1980 | |
1eb787ec | 1981 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
83d5e5b0 | 1982 | map = dm_get_live_table_fast(md); |
8a57dfc6 | 1983 | if (map) { |
cec47e3d KU |
1984 | /* |
1985 | * Request-based dm cares about only own queue for | |
1986 | * the query about congestion status of request_queue | |
1987 | */ | |
1988 | if (dm_request_based(md)) | |
1989 | r = md->queue->backing_dev_info.state & | |
1990 | bdi_bits; | |
1991 | else | |
1992 | r = dm_table_any_congested(map, bdi_bits); | |
8a57dfc6 | 1993 | } |
83d5e5b0 | 1994 | dm_put_live_table_fast(md); |
8a57dfc6 CS |
1995 | } |
1996 | ||
1da177e4 LT |
1997 | return r; |
1998 | } | |
1999 | ||
2000 | /*----------------------------------------------------------------- | |
2001 | * An IDR is used to keep track of allocated minor numbers. | |
2002 | *---------------------------------------------------------------*/ | |
2b06cfff | 2003 | static void free_minor(int minor) |
1da177e4 | 2004 | { |
f32c10b0 | 2005 | spin_lock(&_minor_lock); |
1da177e4 | 2006 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 2007 | spin_unlock(&_minor_lock); |
1da177e4 LT |
2008 | } |
2009 | ||
2010 | /* | |
2011 | * See if the device with a specific minor # is free. | |
2012 | */ | |
cf13ab8e | 2013 | static int specific_minor(int minor) |
1da177e4 | 2014 | { |
c9d76be6 | 2015 | int r; |
1da177e4 LT |
2016 | |
2017 | if (minor >= (1 << MINORBITS)) | |
2018 | return -EINVAL; | |
2019 | ||
c9d76be6 | 2020 | idr_preload(GFP_KERNEL); |
f32c10b0 | 2021 | spin_lock(&_minor_lock); |
1da177e4 | 2022 | |
c9d76be6 | 2023 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT); |
1da177e4 | 2024 | |
f32c10b0 | 2025 | spin_unlock(&_minor_lock); |
c9d76be6 TH |
2026 | idr_preload_end(); |
2027 | if (r < 0) | |
2028 | return r == -ENOSPC ? -EBUSY : r; | |
2029 | return 0; | |
1da177e4 LT |
2030 | } |
2031 | ||
cf13ab8e | 2032 | static int next_free_minor(int *minor) |
1da177e4 | 2033 | { |
c9d76be6 | 2034 | int r; |
62f75c2f | 2035 | |
c9d76be6 | 2036 | idr_preload(GFP_KERNEL); |
f32c10b0 | 2037 | spin_lock(&_minor_lock); |
1da177e4 | 2038 | |
c9d76be6 | 2039 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT); |
1da177e4 | 2040 | |
f32c10b0 | 2041 | spin_unlock(&_minor_lock); |
c9d76be6 TH |
2042 | idr_preload_end(); |
2043 | if (r < 0) | |
2044 | return r; | |
2045 | *minor = r; | |
2046 | return 0; | |
1da177e4 LT |
2047 | } |
2048 | ||
83d5cde4 | 2049 | static const struct block_device_operations dm_blk_dops; |
1da177e4 | 2050 | |
53d5914f MP |
2051 | static void dm_wq_work(struct work_struct *work); |
2052 | ||
4a0b4ddf MS |
2053 | static void dm_init_md_queue(struct mapped_device *md) |
2054 | { | |
2055 | /* | |
2056 | * Request-based dm devices cannot be stacked on top of bio-based dm | |
2057 | * devices. The type of this dm device has not been decided yet. | |
2058 | * The type is decided at the first table loading time. | |
2059 | * To prevent problematic device stacking, clear the queue flag | |
2060 | * for request stacking support until then. | |
2061 | * | |
2062 | * This queue is new, so no concurrency on the queue_flags. | |
2063 | */ | |
2064 | queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue); | |
2065 | ||
2066 | md->queue->queuedata = md; | |
2067 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
2068 | md->queue->backing_dev_info.congested_data = md; | |
2069 | blk_queue_make_request(md->queue, dm_request); | |
2070 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); | |
4a0b4ddf MS |
2071 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); |
2072 | } | |
2073 | ||
1da177e4 LT |
2074 | /* |
2075 | * Allocate and initialise a blank device with a given minor. | |
2076 | */ | |
2b06cfff | 2077 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
2078 | { |
2079 | int r; | |
cf13ab8e | 2080 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 2081 | void *old_md; |
1da177e4 LT |
2082 | |
2083 | if (!md) { | |
2084 | DMWARN("unable to allocate device, out of memory."); | |
2085 | return NULL; | |
2086 | } | |
2087 | ||
10da4f79 | 2088 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 2089 | goto bad_module_get; |
10da4f79 | 2090 | |
1da177e4 | 2091 | /* get a minor number for the dev */ |
2b06cfff | 2092 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 2093 | r = next_free_minor(&minor); |
2b06cfff | 2094 | else |
cf13ab8e | 2095 | r = specific_minor(minor); |
1da177e4 | 2096 | if (r < 0) |
6ed7ade8 | 2097 | goto bad_minor; |
1da177e4 | 2098 | |
83d5e5b0 MP |
2099 | r = init_srcu_struct(&md->io_barrier); |
2100 | if (r < 0) | |
2101 | goto bad_io_barrier; | |
2102 | ||
a5664dad | 2103 | md->type = DM_TYPE_NONE; |
e61290a4 | 2104 | mutex_init(&md->suspend_lock); |
a5664dad | 2105 | mutex_init(&md->type_lock); |
86f1152b | 2106 | mutex_init(&md->table_devices_lock); |
022c2611 | 2107 | spin_lock_init(&md->deferred_lock); |
1da177e4 | 2108 | atomic_set(&md->holders, 1); |
5c6bd75d | 2109 | atomic_set(&md->open_count, 0); |
1da177e4 | 2110 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
2111 | atomic_set(&md->uevent_seq, 0); |
2112 | INIT_LIST_HEAD(&md->uevent_list); | |
86f1152b | 2113 | INIT_LIST_HEAD(&md->table_devices); |
7a8c3d3b | 2114 | spin_lock_init(&md->uevent_lock); |
1da177e4 | 2115 | |
4a0b4ddf | 2116 | md->queue = blk_alloc_queue(GFP_KERNEL); |
1da177e4 | 2117 | if (!md->queue) |
6ed7ade8 | 2118 | goto bad_queue; |
1da177e4 | 2119 | |
4a0b4ddf | 2120 | dm_init_md_queue(md); |
9faf400f | 2121 | |
1da177e4 LT |
2122 | md->disk = alloc_disk(1); |
2123 | if (!md->disk) | |
6ed7ade8 | 2124 | goto bad_disk; |
1da177e4 | 2125 | |
316d315b NK |
2126 | atomic_set(&md->pending[0], 0); |
2127 | atomic_set(&md->pending[1], 0); | |
f0b04115 | 2128 | init_waitqueue_head(&md->wait); |
53d5914f | 2129 | INIT_WORK(&md->work, dm_wq_work); |
f0b04115 | 2130 | init_waitqueue_head(&md->eventq); |
2995fa78 | 2131 | init_completion(&md->kobj_holder.completion); |
f0b04115 | 2132 | |
1da177e4 LT |
2133 | md->disk->major = _major; |
2134 | md->disk->first_minor = minor; | |
2135 | md->disk->fops = &dm_blk_dops; | |
2136 | md->disk->queue = md->queue; | |
2137 | md->disk->private_data = md; | |
2138 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
2139 | add_disk(md->disk); | |
7e51f257 | 2140 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 2141 | |
670368a8 | 2142 | md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0); |
304f3f6a MB |
2143 | if (!md->wq) |
2144 | goto bad_thread; | |
2145 | ||
32a926da MP |
2146 | md->bdev = bdget_disk(md->disk, 0); |
2147 | if (!md->bdev) | |
2148 | goto bad_bdev; | |
2149 | ||
6a8736d1 TH |
2150 | bio_init(&md->flush_bio); |
2151 | md->flush_bio.bi_bdev = md->bdev; | |
2152 | md->flush_bio.bi_rw = WRITE_FLUSH; | |
2153 | ||
fd2ed4d2 MP |
2154 | dm_stats_init(&md->stats); |
2155 | ||
ba61fdd1 | 2156 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 2157 | spin_lock(&_minor_lock); |
ba61fdd1 | 2158 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 2159 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
2160 | |
2161 | BUG_ON(old_md != MINOR_ALLOCED); | |
2162 | ||
1da177e4 LT |
2163 | return md; |
2164 | ||
32a926da MP |
2165 | bad_bdev: |
2166 | destroy_workqueue(md->wq); | |
304f3f6a | 2167 | bad_thread: |
03022c54 | 2168 | del_gendisk(md->disk); |
304f3f6a | 2169 | put_disk(md->disk); |
6ed7ade8 | 2170 | bad_disk: |
1312f40e | 2171 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 2172 | bad_queue: |
83d5e5b0 MP |
2173 | cleanup_srcu_struct(&md->io_barrier); |
2174 | bad_io_barrier: | |
1da177e4 | 2175 | free_minor(minor); |
6ed7ade8 | 2176 | bad_minor: |
10da4f79 | 2177 | module_put(THIS_MODULE); |
6ed7ade8 | 2178 | bad_module_get: |
1da177e4 LT |
2179 | kfree(md); |
2180 | return NULL; | |
2181 | } | |
2182 | ||
ae9da83f JN |
2183 | static void unlock_fs(struct mapped_device *md); |
2184 | ||
1da177e4 LT |
2185 | static void free_dev(struct mapped_device *md) |
2186 | { | |
f331c029 | 2187 | int minor = MINOR(disk_devt(md->disk)); |
63d94e48 | 2188 | |
32a926da MP |
2189 | unlock_fs(md); |
2190 | bdput(md->bdev); | |
304f3f6a | 2191 | destroy_workqueue(md->wq); |
e6ee8c0b KU |
2192 | if (md->io_pool) |
2193 | mempool_destroy(md->io_pool); | |
1ae49ea2 MS |
2194 | if (md->rq_pool) |
2195 | mempool_destroy(md->rq_pool); | |
e6ee8c0b KU |
2196 | if (md->bs) |
2197 | bioset_free(md->bs); | |
9c47008d | 2198 | blk_integrity_unregister(md->disk); |
1da177e4 | 2199 | del_gendisk(md->disk); |
83d5e5b0 | 2200 | cleanup_srcu_struct(&md->io_barrier); |
86f1152b | 2201 | free_table_devices(&md->table_devices); |
63d94e48 | 2202 | free_minor(minor); |
fba9f90e JM |
2203 | |
2204 | spin_lock(&_minor_lock); | |
2205 | md->disk->private_data = NULL; | |
2206 | spin_unlock(&_minor_lock); | |
2207 | ||
1da177e4 | 2208 | put_disk(md->disk); |
1312f40e | 2209 | blk_cleanup_queue(md->queue); |
fd2ed4d2 | 2210 | dm_stats_cleanup(&md->stats); |
10da4f79 | 2211 | module_put(THIS_MODULE); |
1da177e4 LT |
2212 | kfree(md); |
2213 | } | |
2214 | ||
e6ee8c0b KU |
2215 | static void __bind_mempools(struct mapped_device *md, struct dm_table *t) |
2216 | { | |
c0820cf5 | 2217 | struct dm_md_mempools *p = dm_table_get_md_mempools(t); |
e6ee8c0b | 2218 | |
5f015204 | 2219 | if (md->io_pool && md->bs) { |
16245bdc JN |
2220 | /* The md already has necessary mempools. */ |
2221 | if (dm_table_get_type(t) == DM_TYPE_BIO_BASED) { | |
2222 | /* | |
2223 | * Reload bioset because front_pad may have changed | |
2224 | * because a different table was loaded. | |
2225 | */ | |
2226 | bioset_free(md->bs); | |
2227 | md->bs = p->bs; | |
2228 | p->bs = NULL; | |
2229 | } else if (dm_table_get_type(t) == DM_TYPE_REQUEST_BASED) { | |
16245bdc JN |
2230 | /* |
2231 | * There's no need to reload with request-based dm | |
2232 | * because the size of front_pad doesn't change. | |
2233 | * Note for future: If you are to reload bioset, | |
2234 | * prep-ed requests in the queue may refer | |
2235 | * to bio from the old bioset, so you must walk | |
2236 | * through the queue to unprep. | |
2237 | */ | |
2238 | } | |
e6ee8c0b | 2239 | goto out; |
c0820cf5 | 2240 | } |
e6ee8c0b | 2241 | |
1ae49ea2 | 2242 | BUG_ON(!p || md->io_pool || md->rq_pool || md->bs); |
e6ee8c0b KU |
2243 | |
2244 | md->io_pool = p->io_pool; | |
2245 | p->io_pool = NULL; | |
1ae49ea2 MS |
2246 | md->rq_pool = p->rq_pool; |
2247 | p->rq_pool = NULL; | |
e6ee8c0b KU |
2248 | md->bs = p->bs; |
2249 | p->bs = NULL; | |
2250 | ||
2251 | out: | |
2252 | /* mempool bind completed, now no need any mempools in the table */ | |
2253 | dm_table_free_md_mempools(t); | |
2254 | } | |
2255 | ||
1da177e4 LT |
2256 | /* |
2257 | * Bind a table to the device. | |
2258 | */ | |
2259 | static void event_callback(void *context) | |
2260 | { | |
7a8c3d3b MA |
2261 | unsigned long flags; |
2262 | LIST_HEAD(uevents); | |
1da177e4 LT |
2263 | struct mapped_device *md = (struct mapped_device *) context; |
2264 | ||
7a8c3d3b MA |
2265 | spin_lock_irqsave(&md->uevent_lock, flags); |
2266 | list_splice_init(&md->uevent_list, &uevents); | |
2267 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2268 | ||
ed9e1982 | 2269 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
7a8c3d3b | 2270 | |
1da177e4 LT |
2271 | atomic_inc(&md->event_nr); |
2272 | wake_up(&md->eventq); | |
2273 | } | |
2274 | ||
c217649b MS |
2275 | /* |
2276 | * Protected by md->suspend_lock obtained by dm_swap_table(). | |
2277 | */ | |
4e90188b | 2278 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 2279 | { |
4e90188b | 2280 | set_capacity(md->disk, size); |
1da177e4 | 2281 | |
db8fef4f | 2282 | i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
1da177e4 LT |
2283 | } |
2284 | ||
d5b9dd04 MP |
2285 | /* |
2286 | * Return 1 if the queue has a compulsory merge_bvec_fn function. | |
2287 | * | |
2288 | * If this function returns 0, then the device is either a non-dm | |
2289 | * device without a merge_bvec_fn, or it is a dm device that is | |
2290 | * able to split any bios it receives that are too big. | |
2291 | */ | |
2292 | int dm_queue_merge_is_compulsory(struct request_queue *q) | |
2293 | { | |
2294 | struct mapped_device *dev_md; | |
2295 | ||
2296 | if (!q->merge_bvec_fn) | |
2297 | return 0; | |
2298 | ||
2299 | if (q->make_request_fn == dm_request) { | |
2300 | dev_md = q->queuedata; | |
2301 | if (test_bit(DMF_MERGE_IS_OPTIONAL, &dev_md->flags)) | |
2302 | return 0; | |
2303 | } | |
2304 | ||
2305 | return 1; | |
2306 | } | |
2307 | ||
2308 | static int dm_device_merge_is_compulsory(struct dm_target *ti, | |
2309 | struct dm_dev *dev, sector_t start, | |
2310 | sector_t len, void *data) | |
2311 | { | |
2312 | struct block_device *bdev = dev->bdev; | |
2313 | struct request_queue *q = bdev_get_queue(bdev); | |
2314 | ||
2315 | return dm_queue_merge_is_compulsory(q); | |
2316 | } | |
2317 | ||
2318 | /* | |
2319 | * Return 1 if it is acceptable to ignore merge_bvec_fn based | |
2320 | * on the properties of the underlying devices. | |
2321 | */ | |
2322 | static int dm_table_merge_is_optional(struct dm_table *table) | |
2323 | { | |
2324 | unsigned i = 0; | |
2325 | struct dm_target *ti; | |
2326 | ||
2327 | while (i < dm_table_get_num_targets(table)) { | |
2328 | ti = dm_table_get_target(table, i++); | |
2329 | ||
2330 | if (ti->type->iterate_devices && | |
2331 | ti->type->iterate_devices(ti, dm_device_merge_is_compulsory, NULL)) | |
2332 | return 0; | |
2333 | } | |
2334 | ||
2335 | return 1; | |
2336 | } | |
2337 | ||
042d2a9b AK |
2338 | /* |
2339 | * Returns old map, which caller must destroy. | |
2340 | */ | |
2341 | static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, | |
2342 | struct queue_limits *limits) | |
1da177e4 | 2343 | { |
042d2a9b | 2344 | struct dm_table *old_map; |
165125e1 | 2345 | struct request_queue *q = md->queue; |
1da177e4 | 2346 | sector_t size; |
d5b9dd04 | 2347 | int merge_is_optional; |
1da177e4 LT |
2348 | |
2349 | size = dm_table_get_size(t); | |
3ac51e74 DW |
2350 | |
2351 | /* | |
2352 | * Wipe any geometry if the size of the table changed. | |
2353 | */ | |
fd2ed4d2 | 2354 | if (size != dm_get_size(md)) |
3ac51e74 DW |
2355 | memset(&md->geometry, 0, sizeof(md->geometry)); |
2356 | ||
32a926da | 2357 | __set_size(md, size); |
d5816876 | 2358 | |
2ca3310e AK |
2359 | dm_table_event_callback(t, event_callback, md); |
2360 | ||
e6ee8c0b KU |
2361 | /* |
2362 | * The queue hasn't been stopped yet, if the old table type wasn't | |
2363 | * for request-based during suspension. So stop it to prevent | |
2364 | * I/O mapping before resume. | |
2365 | * This must be done before setting the queue restrictions, | |
2366 | * because request-based dm may be run just after the setting. | |
2367 | */ | |
2368 | if (dm_table_request_based(t) && !blk_queue_stopped(q)) | |
2369 | stop_queue(q); | |
2370 | ||
2371 | __bind_mempools(md, t); | |
2372 | ||
d5b9dd04 MP |
2373 | merge_is_optional = dm_table_merge_is_optional(t); |
2374 | ||
a12f5d48 | 2375 | old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
83d5e5b0 | 2376 | rcu_assign_pointer(md->map, t); |
36a0456f AK |
2377 | md->immutable_target_type = dm_table_get_immutable_target_type(t); |
2378 | ||
754c5fc7 | 2379 | dm_table_set_restrictions(t, q, limits); |
d5b9dd04 MP |
2380 | if (merge_is_optional) |
2381 | set_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
2382 | else | |
2383 | clear_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
41abc4e1 HR |
2384 | if (old_map) |
2385 | dm_sync_table(md); | |
1da177e4 | 2386 | |
042d2a9b | 2387 | return old_map; |
1da177e4 LT |
2388 | } |
2389 | ||
a7940155 AK |
2390 | /* |
2391 | * Returns unbound table for the caller to free. | |
2392 | */ | |
2393 | static struct dm_table *__unbind(struct mapped_device *md) | |
1da177e4 | 2394 | { |
a12f5d48 | 2395 | struct dm_table *map = rcu_dereference_protected(md->map, 1); |
1da177e4 LT |
2396 | |
2397 | if (!map) | |
a7940155 | 2398 | return NULL; |
1da177e4 LT |
2399 | |
2400 | dm_table_event_callback(map, NULL, NULL); | |
9cdb8520 | 2401 | RCU_INIT_POINTER(md->map, NULL); |
83d5e5b0 | 2402 | dm_sync_table(md); |
a7940155 AK |
2403 | |
2404 | return map; | |
1da177e4 LT |
2405 | } |
2406 | ||
2407 | /* | |
2408 | * Constructor for a new device. | |
2409 | */ | |
2b06cfff | 2410 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
2411 | { |
2412 | struct mapped_device *md; | |
2413 | ||
2b06cfff | 2414 | md = alloc_dev(minor); |
1da177e4 LT |
2415 | if (!md) |
2416 | return -ENXIO; | |
2417 | ||
784aae73 MB |
2418 | dm_sysfs_init(md); |
2419 | ||
1da177e4 LT |
2420 | *result = md; |
2421 | return 0; | |
2422 | } | |
2423 | ||
a5664dad MS |
2424 | /* |
2425 | * Functions to manage md->type. | |
2426 | * All are required to hold md->type_lock. | |
2427 | */ | |
2428 | void dm_lock_md_type(struct mapped_device *md) | |
2429 | { | |
2430 | mutex_lock(&md->type_lock); | |
2431 | } | |
2432 | ||
2433 | void dm_unlock_md_type(struct mapped_device *md) | |
2434 | { | |
2435 | mutex_unlock(&md->type_lock); | |
2436 | } | |
2437 | ||
2438 | void dm_set_md_type(struct mapped_device *md, unsigned type) | |
2439 | { | |
00c4fc3b | 2440 | BUG_ON(!mutex_is_locked(&md->type_lock)); |
a5664dad MS |
2441 | md->type = type; |
2442 | } | |
2443 | ||
2444 | unsigned dm_get_md_type(struct mapped_device *md) | |
2445 | { | |
00c4fc3b | 2446 | BUG_ON(!mutex_is_locked(&md->type_lock)); |
a5664dad MS |
2447 | return md->type; |
2448 | } | |
2449 | ||
36a0456f AK |
2450 | struct target_type *dm_get_immutable_target_type(struct mapped_device *md) |
2451 | { | |
2452 | return md->immutable_target_type; | |
2453 | } | |
2454 | ||
f84cb8a4 MS |
2455 | /* |
2456 | * The queue_limits are only valid as long as you have a reference | |
2457 | * count on 'md'. | |
2458 | */ | |
2459 | struct queue_limits *dm_get_queue_limits(struct mapped_device *md) | |
2460 | { | |
2461 | BUG_ON(!atomic_read(&md->holders)); | |
2462 | return &md->queue->limits; | |
2463 | } | |
2464 | EXPORT_SYMBOL_GPL(dm_get_queue_limits); | |
2465 | ||
4a0b4ddf MS |
2466 | /* |
2467 | * Fully initialize a request-based queue (->elevator, ->request_fn, etc). | |
2468 | */ | |
2469 | static int dm_init_request_based_queue(struct mapped_device *md) | |
2470 | { | |
2471 | struct request_queue *q = NULL; | |
2472 | ||
2473 | if (md->queue->elevator) | |
2474 | return 1; | |
2475 | ||
2476 | /* Fully initialize the queue */ | |
2477 | q = blk_init_allocated_queue(md->queue, dm_request_fn, NULL); | |
2478 | if (!q) | |
2479 | return 0; | |
2480 | ||
2481 | md->queue = q; | |
4a0b4ddf MS |
2482 | dm_init_md_queue(md); |
2483 | blk_queue_softirq_done(md->queue, dm_softirq_done); | |
2484 | blk_queue_prep_rq(md->queue, dm_prep_fn); | |
2485 | blk_queue_lld_busy(md->queue, dm_lld_busy); | |
4a0b4ddf MS |
2486 | |
2487 | elv_register_queue(md->queue); | |
2488 | ||
2489 | return 1; | |
2490 | } | |
2491 | ||
2492 | /* | |
2493 | * Setup the DM device's queue based on md's type | |
2494 | */ | |
2495 | int dm_setup_md_queue(struct mapped_device *md) | |
2496 | { | |
2497 | if ((dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) && | |
2498 | !dm_init_request_based_queue(md)) { | |
2499 | DMWARN("Cannot initialize queue for request-based mapped device"); | |
2500 | return -EINVAL; | |
2501 | } | |
2502 | ||
2503 | return 0; | |
2504 | } | |
2505 | ||
637842cf | 2506 | static struct mapped_device *dm_find_md(dev_t dev) |
1da177e4 LT |
2507 | { |
2508 | struct mapped_device *md; | |
1da177e4 LT |
2509 | unsigned minor = MINOR(dev); |
2510 | ||
2511 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
2512 | return NULL; | |
2513 | ||
f32c10b0 | 2514 | spin_lock(&_minor_lock); |
1da177e4 LT |
2515 | |
2516 | md = idr_find(&_minor_idr, minor); | |
fba9f90e | 2517 | if (md && (md == MINOR_ALLOCED || |
f331c029 | 2518 | (MINOR(disk_devt(dm_disk(md))) != minor) || |
abdc568b | 2519 | dm_deleting_md(md) || |
17b2f66f | 2520 | test_bit(DMF_FREEING, &md->flags))) { |
637842cf | 2521 | md = NULL; |
fba9f90e JM |
2522 | goto out; |
2523 | } | |
1da177e4 | 2524 | |
fba9f90e | 2525 | out: |
f32c10b0 | 2526 | spin_unlock(&_minor_lock); |
1da177e4 | 2527 | |
637842cf DT |
2528 | return md; |
2529 | } | |
2530 | ||
d229a958 DT |
2531 | struct mapped_device *dm_get_md(dev_t dev) |
2532 | { | |
2533 | struct mapped_device *md = dm_find_md(dev); | |
2534 | ||
2535 | if (md) | |
2536 | dm_get(md); | |
2537 | ||
2538 | return md; | |
2539 | } | |
3cf2e4ba | 2540 | EXPORT_SYMBOL_GPL(dm_get_md); |
d229a958 | 2541 | |
9ade92a9 | 2542 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 2543 | { |
9ade92a9 | 2544 | return md->interface_ptr; |
1da177e4 LT |
2545 | } |
2546 | ||
2547 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
2548 | { | |
2549 | md->interface_ptr = ptr; | |
2550 | } | |
2551 | ||
2552 | void dm_get(struct mapped_device *md) | |
2553 | { | |
2554 | atomic_inc(&md->holders); | |
3f77316d | 2555 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
1da177e4 LT |
2556 | } |
2557 | ||
72d94861 AK |
2558 | const char *dm_device_name(struct mapped_device *md) |
2559 | { | |
2560 | return md->name; | |
2561 | } | |
2562 | EXPORT_SYMBOL_GPL(dm_device_name); | |
2563 | ||
3f77316d | 2564 | static void __dm_destroy(struct mapped_device *md, bool wait) |
1da177e4 | 2565 | { |
1134e5ae | 2566 | struct dm_table *map; |
83d5e5b0 | 2567 | int srcu_idx; |
1da177e4 | 2568 | |
3f77316d | 2569 | might_sleep(); |
fba9f90e | 2570 | |
3f77316d | 2571 | spin_lock(&_minor_lock); |
83d5e5b0 | 2572 | map = dm_get_live_table(md, &srcu_idx); |
3f77316d KU |
2573 | idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); |
2574 | set_bit(DMF_FREEING, &md->flags); | |
2575 | spin_unlock(&_minor_lock); | |
2576 | ||
2577 | if (!dm_suspended_md(md)) { | |
2578 | dm_table_presuspend_targets(map); | |
2579 | dm_table_postsuspend_targets(map); | |
1da177e4 | 2580 | } |
3f77316d | 2581 | |
83d5e5b0 MP |
2582 | /* dm_put_live_table must be before msleep, otherwise deadlock is possible */ |
2583 | dm_put_live_table(md, srcu_idx); | |
2584 | ||
3f77316d KU |
2585 | /* |
2586 | * Rare, but there may be I/O requests still going to complete, | |
2587 | * for example. Wait for all references to disappear. | |
2588 | * No one should increment the reference count of the mapped_device, | |
2589 | * after the mapped_device state becomes DMF_FREEING. | |
2590 | */ | |
2591 | if (wait) | |
2592 | while (atomic_read(&md->holders)) | |
2593 | msleep(1); | |
2594 | else if (atomic_read(&md->holders)) | |
2595 | DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", | |
2596 | dm_device_name(md), atomic_read(&md->holders)); | |
2597 | ||
2598 | dm_sysfs_exit(md); | |
3f77316d KU |
2599 | dm_table_destroy(__unbind(md)); |
2600 | free_dev(md); | |
2601 | } | |
2602 | ||
2603 | void dm_destroy(struct mapped_device *md) | |
2604 | { | |
2605 | __dm_destroy(md, true); | |
2606 | } | |
2607 | ||
2608 | void dm_destroy_immediate(struct mapped_device *md) | |
2609 | { | |
2610 | __dm_destroy(md, false); | |
2611 | } | |
2612 | ||
2613 | void dm_put(struct mapped_device *md) | |
2614 | { | |
2615 | atomic_dec(&md->holders); | |
1da177e4 | 2616 | } |
79eb885c | 2617 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 2618 | |
401600df | 2619 | static int dm_wait_for_completion(struct mapped_device *md, int interruptible) |
46125c1c MB |
2620 | { |
2621 | int r = 0; | |
b44ebeb0 MP |
2622 | DECLARE_WAITQUEUE(wait, current); |
2623 | ||
b44ebeb0 | 2624 | add_wait_queue(&md->wait, &wait); |
46125c1c MB |
2625 | |
2626 | while (1) { | |
401600df | 2627 | set_current_state(interruptible); |
46125c1c | 2628 | |
b4324fee | 2629 | if (!md_in_flight(md)) |
46125c1c MB |
2630 | break; |
2631 | ||
401600df MP |
2632 | if (interruptible == TASK_INTERRUPTIBLE && |
2633 | signal_pending(current)) { | |
46125c1c MB |
2634 | r = -EINTR; |
2635 | break; | |
2636 | } | |
2637 | ||
2638 | io_schedule(); | |
2639 | } | |
2640 | set_current_state(TASK_RUNNING); | |
2641 | ||
b44ebeb0 MP |
2642 | remove_wait_queue(&md->wait, &wait); |
2643 | ||
46125c1c MB |
2644 | return r; |
2645 | } | |
2646 | ||
1da177e4 LT |
2647 | /* |
2648 | * Process the deferred bios | |
2649 | */ | |
ef208587 | 2650 | static void dm_wq_work(struct work_struct *work) |
1da177e4 | 2651 | { |
ef208587 MP |
2652 | struct mapped_device *md = container_of(work, struct mapped_device, |
2653 | work); | |
6d6f10df | 2654 | struct bio *c; |
83d5e5b0 MP |
2655 | int srcu_idx; |
2656 | struct dm_table *map; | |
1da177e4 | 2657 | |
83d5e5b0 | 2658 | map = dm_get_live_table(md, &srcu_idx); |
ef208587 | 2659 | |
3b00b203 | 2660 | while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
df12ee99 AK |
2661 | spin_lock_irq(&md->deferred_lock); |
2662 | c = bio_list_pop(&md->deferred); | |
2663 | spin_unlock_irq(&md->deferred_lock); | |
2664 | ||
6a8736d1 | 2665 | if (!c) |
df12ee99 | 2666 | break; |
022c2611 | 2667 | |
e6ee8c0b KU |
2668 | if (dm_request_based(md)) |
2669 | generic_make_request(c); | |
6a8736d1 | 2670 | else |
83d5e5b0 | 2671 | __split_and_process_bio(md, map, c); |
022c2611 | 2672 | } |
73d410c0 | 2673 | |
83d5e5b0 | 2674 | dm_put_live_table(md, srcu_idx); |
1da177e4 LT |
2675 | } |
2676 | ||
9a1fb464 | 2677 | static void dm_queue_flush(struct mapped_device *md) |
304f3f6a | 2678 | { |
3b00b203 | 2679 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
4e857c58 | 2680 | smp_mb__after_atomic(); |
53d5914f | 2681 | queue_work(md->wq, &md->work); |
304f3f6a MB |
2682 | } |
2683 | ||
1da177e4 | 2684 | /* |
042d2a9b | 2685 | * Swap in a new table, returning the old one for the caller to destroy. |
1da177e4 | 2686 | */ |
042d2a9b | 2687 | struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) |
1da177e4 | 2688 | { |
87eb5b21 | 2689 | struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL); |
754c5fc7 | 2690 | struct queue_limits limits; |
042d2a9b | 2691 | int r; |
1da177e4 | 2692 | |
e61290a4 | 2693 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
2694 | |
2695 | /* device must be suspended */ | |
4f186f8b | 2696 | if (!dm_suspended_md(md)) |
93c534ae | 2697 | goto out; |
1da177e4 | 2698 | |
3ae70656 MS |
2699 | /* |
2700 | * If the new table has no data devices, retain the existing limits. | |
2701 | * This helps multipath with queue_if_no_path if all paths disappear, | |
2702 | * then new I/O is queued based on these limits, and then some paths | |
2703 | * reappear. | |
2704 | */ | |
2705 | if (dm_table_has_no_data_devices(table)) { | |
83d5e5b0 | 2706 | live_map = dm_get_live_table_fast(md); |
3ae70656 MS |
2707 | if (live_map) |
2708 | limits = md->queue->limits; | |
83d5e5b0 | 2709 | dm_put_live_table_fast(md); |
3ae70656 MS |
2710 | } |
2711 | ||
87eb5b21 MC |
2712 | if (!live_map) { |
2713 | r = dm_calculate_queue_limits(table, &limits); | |
2714 | if (r) { | |
2715 | map = ERR_PTR(r); | |
2716 | goto out; | |
2717 | } | |
042d2a9b | 2718 | } |
754c5fc7 | 2719 | |
042d2a9b | 2720 | map = __bind(md, table, &limits); |
1da177e4 | 2721 | |
93c534ae | 2722 | out: |
e61290a4 | 2723 | mutex_unlock(&md->suspend_lock); |
042d2a9b | 2724 | return map; |
1da177e4 LT |
2725 | } |
2726 | ||
2727 | /* | |
2728 | * Functions to lock and unlock any filesystem running on the | |
2729 | * device. | |
2730 | */ | |
2ca3310e | 2731 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 2732 | { |
e39e2e95 | 2733 | int r; |
1da177e4 LT |
2734 | |
2735 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 2736 | |
db8fef4f | 2737 | md->frozen_sb = freeze_bdev(md->bdev); |
dfbe03f6 | 2738 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 2739 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
2740 | md->frozen_sb = NULL; |
2741 | return r; | |
dfbe03f6 AK |
2742 | } |
2743 | ||
aa8d7c2f AK |
2744 | set_bit(DMF_FROZEN, &md->flags); |
2745 | ||
1da177e4 LT |
2746 | return 0; |
2747 | } | |
2748 | ||
2ca3310e | 2749 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 2750 | { |
aa8d7c2f AK |
2751 | if (!test_bit(DMF_FROZEN, &md->flags)) |
2752 | return; | |
2753 | ||
db8fef4f | 2754 | thaw_bdev(md->bdev, md->frozen_sb); |
1da177e4 | 2755 | md->frozen_sb = NULL; |
aa8d7c2f | 2756 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
2757 | } |
2758 | ||
2759 | /* | |
ffcc3936 MS |
2760 | * If __dm_suspend returns 0, the device is completely quiescent |
2761 | * now. There is no request-processing activity. All new requests | |
2762 | * are being added to md->deferred list. | |
cec47e3d | 2763 | * |
ffcc3936 | 2764 | * Caller must hold md->suspend_lock |
cec47e3d | 2765 | */ |
ffcc3936 MS |
2766 | static int __dm_suspend(struct mapped_device *md, struct dm_table *map, |
2767 | unsigned suspend_flags, int interruptible) | |
1da177e4 | 2768 | { |
ffcc3936 MS |
2769 | bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG; |
2770 | bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG; | |
2771 | int r; | |
1da177e4 | 2772 | |
2e93ccc1 KU |
2773 | /* |
2774 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
2775 | * This flag is cleared before dm_suspend returns. | |
2776 | */ | |
2777 | if (noflush) | |
2778 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
2779 | ||
d67ee213 MS |
2780 | /* |
2781 | * This gets reverted if there's an error later and the targets | |
2782 | * provide the .presuspend_undo hook. | |
2783 | */ | |
cf222b37 AK |
2784 | dm_table_presuspend_targets(map); |
2785 | ||
32a926da | 2786 | /* |
9f518b27 KU |
2787 | * Flush I/O to the device. |
2788 | * Any I/O submitted after lock_fs() may not be flushed. | |
2789 | * noflush takes precedence over do_lockfs. | |
2790 | * (lock_fs() flushes I/Os and waits for them to complete.) | |
32a926da MP |
2791 | */ |
2792 | if (!noflush && do_lockfs) { | |
2793 | r = lock_fs(md); | |
d67ee213 MS |
2794 | if (r) { |
2795 | dm_table_presuspend_undo_targets(map); | |
ffcc3936 | 2796 | return r; |
d67ee213 | 2797 | } |
aa8d7c2f | 2798 | } |
1da177e4 LT |
2799 | |
2800 | /* | |
3b00b203 MP |
2801 | * Here we must make sure that no processes are submitting requests |
2802 | * to target drivers i.e. no one may be executing | |
2803 | * __split_and_process_bio. This is called from dm_request and | |
2804 | * dm_wq_work. | |
2805 | * | |
2806 | * To get all processes out of __split_and_process_bio in dm_request, | |
2807 | * we take the write lock. To prevent any process from reentering | |
6a8736d1 TH |
2808 | * __split_and_process_bio from dm_request and quiesce the thread |
2809 | * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call | |
2810 | * flush_workqueue(md->wq). | |
1da177e4 | 2811 | */ |
1eb787ec | 2812 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
41abc4e1 HR |
2813 | if (map) |
2814 | synchronize_srcu(&md->io_barrier); | |
1da177e4 | 2815 | |
d0bcb878 | 2816 | /* |
29e4013d TH |
2817 | * Stop md->queue before flushing md->wq in case request-based |
2818 | * dm defers requests to md->wq from md->queue. | |
d0bcb878 | 2819 | */ |
cec47e3d | 2820 | if (dm_request_based(md)) |
9f518b27 | 2821 | stop_queue(md->queue); |
cec47e3d | 2822 | |
d0bcb878 KU |
2823 | flush_workqueue(md->wq); |
2824 | ||
1da177e4 | 2825 | /* |
3b00b203 MP |
2826 | * At this point no more requests are entering target request routines. |
2827 | * We call dm_wait_for_completion to wait for all existing requests | |
2828 | * to finish. | |
1da177e4 | 2829 | */ |
ffcc3936 | 2830 | r = dm_wait_for_completion(md, interruptible); |
1da177e4 | 2831 | |
6d6f10df | 2832 | if (noflush) |
022c2611 | 2833 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
41abc4e1 HR |
2834 | if (map) |
2835 | synchronize_srcu(&md->io_barrier); | |
2e93ccc1 | 2836 | |
1da177e4 | 2837 | /* were we interrupted ? */ |
46125c1c | 2838 | if (r < 0) { |
9a1fb464 | 2839 | dm_queue_flush(md); |
73d410c0 | 2840 | |
cec47e3d | 2841 | if (dm_request_based(md)) |
9f518b27 | 2842 | start_queue(md->queue); |
cec47e3d | 2843 | |
2ca3310e | 2844 | unlock_fs(md); |
d67ee213 | 2845 | dm_table_presuspend_undo_targets(map); |
ffcc3936 | 2846 | /* pushback list is already flushed, so skip flush */ |
2ca3310e | 2847 | } |
1da177e4 | 2848 | |
ffcc3936 MS |
2849 | return r; |
2850 | } | |
2851 | ||
2852 | /* | |
2853 | * We need to be able to change a mapping table under a mounted | |
2854 | * filesystem. For example we might want to move some data in | |
2855 | * the background. Before the table can be swapped with | |
2856 | * dm_bind_table, dm_suspend must be called to flush any in | |
2857 | * flight bios and ensure that any further io gets deferred. | |
2858 | */ | |
2859 | /* | |
2860 | * Suspend mechanism in request-based dm. | |
2861 | * | |
2862 | * 1. Flush all I/Os by lock_fs() if needed. | |
2863 | * 2. Stop dispatching any I/O by stopping the request_queue. | |
2864 | * 3. Wait for all in-flight I/Os to be completed or requeued. | |
2865 | * | |
2866 | * To abort suspend, start the request_queue. | |
2867 | */ | |
2868 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) | |
2869 | { | |
2870 | struct dm_table *map = NULL; | |
2871 | int r = 0; | |
2872 | ||
2873 | retry: | |
2874 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
2875 | ||
2876 | if (dm_suspended_md(md)) { | |
2877 | r = -EINVAL; | |
2878 | goto out_unlock; | |
2879 | } | |
2880 | ||
2881 | if (dm_suspended_internally_md(md)) { | |
2882 | /* already internally suspended, wait for internal resume */ | |
2883 | mutex_unlock(&md->suspend_lock); | |
2884 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
2885 | if (r) | |
2886 | return r; | |
2887 | goto retry; | |
2888 | } | |
2889 | ||
a12f5d48 | 2890 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
ffcc3936 MS |
2891 | |
2892 | r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE); | |
2893 | if (r) | |
2894 | goto out_unlock; | |
3b00b203 | 2895 | |
2ca3310e | 2896 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 2897 | |
4d4471cb KU |
2898 | dm_table_postsuspend_targets(map); |
2899 | ||
d287483d | 2900 | out_unlock: |
e61290a4 | 2901 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 2902 | return r; |
1da177e4 LT |
2903 | } |
2904 | ||
ffcc3936 MS |
2905 | static int __dm_resume(struct mapped_device *md, struct dm_table *map) |
2906 | { | |
2907 | if (map) { | |
2908 | int r = dm_table_resume_targets(map); | |
2909 | if (r) | |
2910 | return r; | |
2911 | } | |
2912 | ||
2913 | dm_queue_flush(md); | |
2914 | ||
2915 | /* | |
2916 | * Flushing deferred I/Os must be done after targets are resumed | |
2917 | * so that mapping of targets can work correctly. | |
2918 | * Request-based dm is queueing the deferred I/Os in its request_queue. | |
2919 | */ | |
2920 | if (dm_request_based(md)) | |
2921 | start_queue(md->queue); | |
2922 | ||
2923 | unlock_fs(md); | |
2924 | ||
2925 | return 0; | |
2926 | } | |
2927 | ||
1da177e4 LT |
2928 | int dm_resume(struct mapped_device *md) |
2929 | { | |
cf222b37 | 2930 | int r = -EINVAL; |
cf222b37 | 2931 | struct dm_table *map = NULL; |
1da177e4 | 2932 | |
ffcc3936 MS |
2933 | retry: |
2934 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
2935 | ||
4f186f8b | 2936 | if (!dm_suspended_md(md)) |
cf222b37 | 2937 | goto out; |
cf222b37 | 2938 | |
ffcc3936 MS |
2939 | if (dm_suspended_internally_md(md)) { |
2940 | /* already internally suspended, wait for internal resume */ | |
2941 | mutex_unlock(&md->suspend_lock); | |
2942 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
2943 | if (r) | |
2944 | return r; | |
2945 | goto retry; | |
2946 | } | |
2947 | ||
a12f5d48 | 2948 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
2ca3310e | 2949 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 2950 | goto out; |
1da177e4 | 2951 | |
ffcc3936 | 2952 | r = __dm_resume(md, map); |
8757b776 MB |
2953 | if (r) |
2954 | goto out; | |
2ca3310e | 2955 | |
2ca3310e AK |
2956 | clear_bit(DMF_SUSPENDED, &md->flags); |
2957 | ||
cf222b37 AK |
2958 | r = 0; |
2959 | out: | |
e61290a4 | 2960 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 2961 | |
cf222b37 | 2962 | return r; |
1da177e4 LT |
2963 | } |
2964 | ||
fd2ed4d2 MP |
2965 | /* |
2966 | * Internal suspend/resume works like userspace-driven suspend. It waits | |
2967 | * until all bios finish and prevents issuing new bios to the target drivers. | |
2968 | * It may be used only from the kernel. | |
fd2ed4d2 MP |
2969 | */ |
2970 | ||
ffcc3936 | 2971 | static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags) |
fd2ed4d2 | 2972 | { |
ffcc3936 MS |
2973 | struct dm_table *map = NULL; |
2974 | ||
2975 | if (dm_suspended_internally_md(md)) | |
2976 | return; /* nested internal suspend */ | |
2977 | ||
2978 | if (dm_suspended_md(md)) { | |
2979 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
2980 | return; /* nest suspend */ | |
2981 | } | |
2982 | ||
a12f5d48 | 2983 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
ffcc3936 MS |
2984 | |
2985 | /* | |
2986 | * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is | |
2987 | * supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend | |
2988 | * would require changing .presuspend to return an error -- avoid this | |
2989 | * until there is a need for more elaborate variants of internal suspend. | |
2990 | */ | |
2991 | (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE); | |
2992 | ||
2993 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
2994 | ||
2995 | dm_table_postsuspend_targets(map); | |
2996 | } | |
2997 | ||
2998 | static void __dm_internal_resume(struct mapped_device *md) | |
2999 | { | |
3000 | if (!dm_suspended_internally_md(md)) | |
3001 | return; /* resume from nested internal suspend */ | |
3002 | ||
fd2ed4d2 | 3003 | if (dm_suspended_md(md)) |
ffcc3936 MS |
3004 | goto done; /* resume from nested suspend */ |
3005 | ||
3006 | /* | |
3007 | * NOTE: existing callers don't need to call dm_table_resume_targets | |
3008 | * (which may fail -- so best to avoid it for now by passing NULL map) | |
3009 | */ | |
3010 | (void) __dm_resume(md, NULL); | |
3011 | ||
3012 | done: | |
3013 | clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3014 | smp_mb__after_atomic(); | |
3015 | wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY); | |
3016 | } | |
3017 | ||
3018 | void dm_internal_suspend_noflush(struct mapped_device *md) | |
3019 | { | |
3020 | mutex_lock(&md->suspend_lock); | |
3021 | __dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG); | |
3022 | mutex_unlock(&md->suspend_lock); | |
3023 | } | |
3024 | EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush); | |
3025 | ||
3026 | void dm_internal_resume(struct mapped_device *md) | |
3027 | { | |
3028 | mutex_lock(&md->suspend_lock); | |
3029 | __dm_internal_resume(md); | |
3030 | mutex_unlock(&md->suspend_lock); | |
3031 | } | |
3032 | EXPORT_SYMBOL_GPL(dm_internal_resume); | |
3033 | ||
3034 | /* | |
3035 | * Fast variants of internal suspend/resume hold md->suspend_lock, | |
3036 | * which prevents interaction with userspace-driven suspend. | |
3037 | */ | |
3038 | ||
3039 | void dm_internal_suspend_fast(struct mapped_device *md) | |
3040 | { | |
3041 | mutex_lock(&md->suspend_lock); | |
3042 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) | |
fd2ed4d2 MP |
3043 | return; |
3044 | ||
3045 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); | |
3046 | synchronize_srcu(&md->io_barrier); | |
3047 | flush_workqueue(md->wq); | |
3048 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); | |
3049 | } | |
3050 | ||
ffcc3936 | 3051 | void dm_internal_resume_fast(struct mapped_device *md) |
fd2ed4d2 | 3052 | { |
ffcc3936 | 3053 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) |
fd2ed4d2 MP |
3054 | goto done; |
3055 | ||
3056 | dm_queue_flush(md); | |
3057 | ||
3058 | done: | |
3059 | mutex_unlock(&md->suspend_lock); | |
3060 | } | |
3061 | ||
1da177e4 LT |
3062 | /*----------------------------------------------------------------- |
3063 | * Event notification. | |
3064 | *---------------------------------------------------------------*/ | |
3abf85b5 | 3065 | int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
60935eb2 | 3066 | unsigned cookie) |
69267a30 | 3067 | { |
60935eb2 MB |
3068 | char udev_cookie[DM_COOKIE_LENGTH]; |
3069 | char *envp[] = { udev_cookie, NULL }; | |
3070 | ||
3071 | if (!cookie) | |
3abf85b5 | 3072 | return kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
60935eb2 MB |
3073 | else { |
3074 | snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", | |
3075 | DM_COOKIE_ENV_VAR_NAME, cookie); | |
3abf85b5 PR |
3076 | return kobject_uevent_env(&disk_to_dev(md->disk)->kobj, |
3077 | action, envp); | |
60935eb2 | 3078 | } |
69267a30 AK |
3079 | } |
3080 | ||
7a8c3d3b MA |
3081 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
3082 | { | |
3083 | return atomic_add_return(1, &md->uevent_seq); | |
3084 | } | |
3085 | ||
1da177e4 LT |
3086 | uint32_t dm_get_event_nr(struct mapped_device *md) |
3087 | { | |
3088 | return atomic_read(&md->event_nr); | |
3089 | } | |
3090 | ||
3091 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
3092 | { | |
3093 | return wait_event_interruptible(md->eventq, | |
3094 | (event_nr != atomic_read(&md->event_nr))); | |
3095 | } | |
3096 | ||
7a8c3d3b MA |
3097 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
3098 | { | |
3099 | unsigned long flags; | |
3100 | ||
3101 | spin_lock_irqsave(&md->uevent_lock, flags); | |
3102 | list_add(elist, &md->uevent_list); | |
3103 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
3104 | } | |
3105 | ||
1da177e4 LT |
3106 | /* |
3107 | * The gendisk is only valid as long as you have a reference | |
3108 | * count on 'md'. | |
3109 | */ | |
3110 | struct gendisk *dm_disk(struct mapped_device *md) | |
3111 | { | |
3112 | return md->disk; | |
3113 | } | |
3114 | ||
784aae73 MB |
3115 | struct kobject *dm_kobject(struct mapped_device *md) |
3116 | { | |
2995fa78 | 3117 | return &md->kobj_holder.kobj; |
784aae73 MB |
3118 | } |
3119 | ||
784aae73 MB |
3120 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) |
3121 | { | |
3122 | struct mapped_device *md; | |
3123 | ||
2995fa78 | 3124 | md = container_of(kobj, struct mapped_device, kobj_holder.kobj); |
784aae73 | 3125 | |
4d89b7b4 | 3126 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 3127 | dm_deleting_md(md)) |
4d89b7b4 MB |
3128 | return NULL; |
3129 | ||
784aae73 MB |
3130 | dm_get(md); |
3131 | return md; | |
3132 | } | |
3133 | ||
4f186f8b | 3134 | int dm_suspended_md(struct mapped_device *md) |
1da177e4 LT |
3135 | { |
3136 | return test_bit(DMF_SUSPENDED, &md->flags); | |
3137 | } | |
3138 | ||
ffcc3936 MS |
3139 | int dm_suspended_internally_md(struct mapped_device *md) |
3140 | { | |
3141 | return test_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3142 | } | |
3143 | ||
2c140a24 MP |
3144 | int dm_test_deferred_remove_flag(struct mapped_device *md) |
3145 | { | |
3146 | return test_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
3147 | } | |
3148 | ||
64dbce58 KU |
3149 | int dm_suspended(struct dm_target *ti) |
3150 | { | |
ecdb2e25 | 3151 | return dm_suspended_md(dm_table_get_md(ti->table)); |
64dbce58 KU |
3152 | } |
3153 | EXPORT_SYMBOL_GPL(dm_suspended); | |
3154 | ||
2e93ccc1 KU |
3155 | int dm_noflush_suspending(struct dm_target *ti) |
3156 | { | |
ecdb2e25 | 3157 | return __noflush_suspending(dm_table_get_md(ti->table)); |
2e93ccc1 KU |
3158 | } |
3159 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
3160 | ||
c0820cf5 | 3161 | struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, unsigned per_bio_data_size) |
e6ee8c0b | 3162 | { |
5f015204 JN |
3163 | struct dm_md_mempools *pools = kzalloc(sizeof(*pools), GFP_KERNEL); |
3164 | struct kmem_cache *cachep; | |
3165 | unsigned int pool_size; | |
3166 | unsigned int front_pad; | |
e6ee8c0b KU |
3167 | |
3168 | if (!pools) | |
3169 | return NULL; | |
3170 | ||
23e5083b | 3171 | if (type == DM_TYPE_BIO_BASED) { |
5f015204 | 3172 | cachep = _io_cache; |
e8603136 | 3173 | pool_size = dm_get_reserved_bio_based_ios(); |
5f015204 JN |
3174 | front_pad = roundup(per_bio_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone); |
3175 | } else if (type == DM_TYPE_REQUEST_BASED) { | |
3176 | cachep = _rq_tio_cache; | |
f4790826 | 3177 | pool_size = dm_get_reserved_rq_based_ios(); |
1ae49ea2 MS |
3178 | pools->rq_pool = mempool_create_slab_pool(pool_size, _rq_cache); |
3179 | if (!pools->rq_pool) | |
3180 | goto out; | |
5f015204 JN |
3181 | front_pad = offsetof(struct dm_rq_clone_bio_info, clone); |
3182 | /* per_bio_data_size is not used. See __bind_mempools(). */ | |
3183 | WARN_ON(per_bio_data_size != 0); | |
3184 | } else | |
3185 | goto out; | |
e6ee8c0b | 3186 | |
6cfa5857 | 3187 | pools->io_pool = mempool_create_slab_pool(pool_size, cachep); |
5f015204 JN |
3188 | if (!pools->io_pool) |
3189 | goto out; | |
e6ee8c0b | 3190 | |
3d8aab2d | 3191 | pools->bs = bioset_create_nobvec(pool_size, front_pad); |
e6ee8c0b | 3192 | if (!pools->bs) |
5f015204 | 3193 | goto out; |
e6ee8c0b | 3194 | |
a91a2785 | 3195 | if (integrity && bioset_integrity_create(pools->bs, pool_size)) |
5f015204 | 3196 | goto out; |
a91a2785 | 3197 | |
e6ee8c0b KU |
3198 | return pools; |
3199 | ||
5f015204 JN |
3200 | out: |
3201 | dm_free_md_mempools(pools); | |
e6ee8c0b KU |
3202 | |
3203 | return NULL; | |
3204 | } | |
3205 | ||
3206 | void dm_free_md_mempools(struct dm_md_mempools *pools) | |
3207 | { | |
3208 | if (!pools) | |
3209 | return; | |
3210 | ||
3211 | if (pools->io_pool) | |
3212 | mempool_destroy(pools->io_pool); | |
3213 | ||
1ae49ea2 MS |
3214 | if (pools->rq_pool) |
3215 | mempool_destroy(pools->rq_pool); | |
3216 | ||
e6ee8c0b KU |
3217 | if (pools->bs) |
3218 | bioset_free(pools->bs); | |
3219 | ||
3220 | kfree(pools); | |
3221 | } | |
3222 | ||
83d5cde4 | 3223 | static const struct block_device_operations dm_blk_dops = { |
1da177e4 LT |
3224 | .open = dm_blk_open, |
3225 | .release = dm_blk_close, | |
aa129a22 | 3226 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 3227 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
3228 | .owner = THIS_MODULE |
3229 | }; | |
3230 | ||
1da177e4 LT |
3231 | /* |
3232 | * module hooks | |
3233 | */ | |
3234 | module_init(dm_init); | |
3235 | module_exit(dm_exit); | |
3236 | ||
3237 | module_param(major, uint, 0); | |
3238 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
f4790826 | 3239 | |
e8603136 MS |
3240 | module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR); |
3241 | MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools"); | |
3242 | ||
f4790826 MS |
3243 | module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR); |
3244 | MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools"); | |
3245 | ||
1da177e4 LT |
3246 | MODULE_DESCRIPTION(DM_NAME " driver"); |
3247 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
3248 | MODULE_LICENSE("GPL"); |