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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. | |
784aae73 | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include "dm.h" | |
51e5b2bd | 9 | #include "dm-uevent.h" |
1da177e4 LT |
10 | |
11 | #include <linux/init.h> | |
12 | #include <linux/module.h> | |
48c9c27b | 13 | #include <linux/mutex.h> |
1da177e4 LT |
14 | #include <linux/moduleparam.h> |
15 | #include <linux/blkpg.h> | |
16 | #include <linux/bio.h> | |
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> |
2eb6e1e3 | 23 | #include <linux/kthread.h> |
55782138 LZ |
24 | |
25 | #include <trace/events/block.h> | |
1da177e4 | 26 | |
72d94861 AK |
27 | #define DM_MSG_PREFIX "core" |
28 | ||
71a16736 NK |
29 | #ifdef CONFIG_PRINTK |
30 | /* | |
31 | * ratelimit state to be used in DMXXX_LIMIT(). | |
32 | */ | |
33 | DEFINE_RATELIMIT_STATE(dm_ratelimit_state, | |
34 | DEFAULT_RATELIMIT_INTERVAL, | |
35 | DEFAULT_RATELIMIT_BURST); | |
36 | EXPORT_SYMBOL(dm_ratelimit_state); | |
37 | #endif | |
38 | ||
60935eb2 MB |
39 | /* |
40 | * Cookies are numeric values sent with CHANGE and REMOVE | |
41 | * uevents while resuming, removing or renaming the device. | |
42 | */ | |
43 | #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" | |
44 | #define DM_COOKIE_LENGTH 24 | |
45 | ||
1da177e4 LT |
46 | static const char *_name = DM_NAME; |
47 | ||
48 | static unsigned int major = 0; | |
49 | static unsigned int _major = 0; | |
50 | ||
d15b774c AK |
51 | static DEFINE_IDR(_minor_idr); |
52 | ||
f32c10b0 | 53 | static DEFINE_SPINLOCK(_minor_lock); |
2c140a24 MP |
54 | |
55 | static void do_deferred_remove(struct work_struct *w); | |
56 | ||
57 | static DECLARE_WORK(deferred_remove_work, do_deferred_remove); | |
58 | ||
acfe0ad7 MP |
59 | static struct workqueue_struct *deferred_remove_workqueue; |
60 | ||
1da177e4 | 61 | /* |
8fbf26ad | 62 | * For bio-based dm. |
1da177e4 LT |
63 | * One of these is allocated per bio. |
64 | */ | |
65 | struct dm_io { | |
66 | struct mapped_device *md; | |
67 | int error; | |
1da177e4 | 68 | atomic_t io_count; |
6ae2fa67 | 69 | struct bio *bio; |
3eaf840e | 70 | unsigned long start_time; |
f88fb981 | 71 | spinlock_t endio_lock; |
fd2ed4d2 | 72 | struct dm_stats_aux stats_aux; |
1da177e4 LT |
73 | }; |
74 | ||
8fbf26ad KU |
75 | /* |
76 | * For request-based dm. | |
77 | * One of these is allocated per request. | |
78 | */ | |
79 | struct dm_rq_target_io { | |
80 | struct mapped_device *md; | |
81 | struct dm_target *ti; | |
1ae49ea2 | 82 | struct request *orig, *clone; |
2eb6e1e3 | 83 | struct kthread_work work; |
8fbf26ad KU |
84 | int error; |
85 | union map_info info; | |
86 | }; | |
87 | ||
88 | /* | |
94818742 KO |
89 | * For request-based dm - the bio clones we allocate are embedded in these |
90 | * structs. | |
91 | * | |
92 | * We allocate these with bio_alloc_bioset, using the front_pad parameter when | |
93 | * the bioset is created - this means the bio has to come at the end of the | |
94 | * struct. | |
8fbf26ad KU |
95 | */ |
96 | struct dm_rq_clone_bio_info { | |
97 | struct bio *orig; | |
cec47e3d | 98 | struct dm_rq_target_io *tio; |
94818742 | 99 | struct bio clone; |
8fbf26ad KU |
100 | }; |
101 | ||
cec47e3d KU |
102 | union map_info *dm_get_rq_mapinfo(struct request *rq) |
103 | { | |
104 | if (rq && rq->end_io_data) | |
105 | return &((struct dm_rq_target_io *)rq->end_io_data)->info; | |
106 | return NULL; | |
107 | } | |
108 | EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo); | |
109 | ||
ba61fdd1 JM |
110 | #define MINOR_ALLOCED ((void *)-1) |
111 | ||
1da177e4 LT |
112 | /* |
113 | * Bits for the md->flags field. | |
114 | */ | |
1eb787ec | 115 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
1da177e4 | 116 | #define DMF_SUSPENDED 1 |
aa8d7c2f | 117 | #define DMF_FROZEN 2 |
fba9f90e | 118 | #define DMF_FREEING 3 |
5c6bd75d | 119 | #define DMF_DELETING 4 |
2e93ccc1 | 120 | #define DMF_NOFLUSH_SUSPENDING 5 |
d5b9dd04 | 121 | #define DMF_MERGE_IS_OPTIONAL 6 |
2c140a24 | 122 | #define DMF_DEFERRED_REMOVE 7 |
ffcc3936 | 123 | #define DMF_SUSPENDED_INTERNALLY 8 |
1da177e4 | 124 | |
83d5e5b0 MP |
125 | /* |
126 | * A dummy definition to make RCU happy. | |
127 | * struct dm_table should never be dereferenced in this file. | |
128 | */ | |
129 | struct dm_table { | |
130 | int undefined__; | |
131 | }; | |
132 | ||
304f3f6a MB |
133 | /* |
134 | * Work processed by per-device workqueue. | |
135 | */ | |
1da177e4 | 136 | struct mapped_device { |
83d5e5b0 | 137 | struct srcu_struct io_barrier; |
e61290a4 | 138 | struct mutex suspend_lock; |
1da177e4 | 139 | atomic_t holders; |
5c6bd75d | 140 | atomic_t open_count; |
1da177e4 | 141 | |
2a7faeb1 MP |
142 | /* |
143 | * The current mapping. | |
144 | * Use dm_get_live_table{_fast} or take suspend_lock for | |
145 | * dereference. | |
146 | */ | |
6fa99520 | 147 | struct dm_table __rcu *map; |
2a7faeb1 | 148 | |
86f1152b BM |
149 | struct list_head table_devices; |
150 | struct mutex table_devices_lock; | |
151 | ||
1da177e4 LT |
152 | unsigned long flags; |
153 | ||
165125e1 | 154 | struct request_queue *queue; |
a5664dad | 155 | unsigned type; |
4a0b4ddf | 156 | /* Protect queue and type against concurrent access. */ |
a5664dad MS |
157 | struct mutex type_lock; |
158 | ||
36a0456f AK |
159 | struct target_type *immutable_target_type; |
160 | ||
1da177e4 | 161 | struct gendisk *disk; |
7e51f257 | 162 | char name[16]; |
1da177e4 LT |
163 | |
164 | void *interface_ptr; | |
165 | ||
166 | /* | |
167 | * A list of ios that arrived while we were suspended. | |
168 | */ | |
316d315b | 169 | atomic_t pending[2]; |
1da177e4 | 170 | wait_queue_head_t wait; |
53d5914f | 171 | struct work_struct work; |
74859364 | 172 | struct bio_list deferred; |
022c2611 | 173 | spinlock_t deferred_lock; |
1da177e4 | 174 | |
af7e466a | 175 | /* |
29e4013d | 176 | * Processing queue (flush) |
304f3f6a MB |
177 | */ |
178 | struct workqueue_struct *wq; | |
179 | ||
1da177e4 LT |
180 | /* |
181 | * io objects are allocated from here. | |
182 | */ | |
183 | mempool_t *io_pool; | |
1ae49ea2 | 184 | mempool_t *rq_pool; |
1da177e4 | 185 | |
9faf400f SB |
186 | struct bio_set *bs; |
187 | ||
1da177e4 LT |
188 | /* |
189 | * Event handling. | |
190 | */ | |
191 | atomic_t event_nr; | |
192 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
193 | atomic_t uevent_seq; |
194 | struct list_head uevent_list; | |
195 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
196 | |
197 | /* | |
198 | * freeze/thaw support require holding onto a super block | |
199 | */ | |
200 | struct super_block *frozen_sb; | |
db8fef4f | 201 | struct block_device *bdev; |
3ac51e74 DW |
202 | |
203 | /* forced geometry settings */ | |
204 | struct hd_geometry geometry; | |
784aae73 | 205 | |
2995fa78 MP |
206 | /* kobject and completion */ |
207 | struct dm_kobject_holder kobj_holder; | |
be35f486 | 208 | |
d87f4c14 TH |
209 | /* zero-length flush that will be cloned and submitted to targets */ |
210 | struct bio flush_bio; | |
fd2ed4d2 | 211 | |
96b26c8c MP |
212 | /* the number of internal suspends */ |
213 | unsigned internal_suspend_count; | |
214 | ||
fd2ed4d2 | 215 | struct dm_stats stats; |
2eb6e1e3 KB |
216 | |
217 | struct kthread_worker kworker; | |
218 | struct task_struct *kworker_task; | |
1da177e4 LT |
219 | }; |
220 | ||
e6ee8c0b KU |
221 | /* |
222 | * For mempools pre-allocation at the table loading time. | |
223 | */ | |
224 | struct dm_md_mempools { | |
225 | mempool_t *io_pool; | |
1ae49ea2 | 226 | mempool_t *rq_pool; |
e6ee8c0b KU |
227 | struct bio_set *bs; |
228 | }; | |
229 | ||
86f1152b BM |
230 | struct table_device { |
231 | struct list_head list; | |
232 | atomic_t count; | |
233 | struct dm_dev dm_dev; | |
234 | }; | |
235 | ||
6cfa5857 MS |
236 | #define RESERVED_BIO_BASED_IOS 16 |
237 | #define RESERVED_REQUEST_BASED_IOS 256 | |
f4790826 | 238 | #define RESERVED_MAX_IOS 1024 |
e18b890b | 239 | static struct kmem_cache *_io_cache; |
8fbf26ad | 240 | static struct kmem_cache *_rq_tio_cache; |
1ae49ea2 | 241 | static struct kmem_cache *_rq_cache; |
94818742 | 242 | |
e8603136 MS |
243 | /* |
244 | * Bio-based DM's mempools' reserved IOs set by the user. | |
245 | */ | |
246 | static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; | |
247 | ||
f4790826 MS |
248 | /* |
249 | * Request-based DM's mempools' reserved IOs set by the user. | |
250 | */ | |
251 | static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS; | |
252 | ||
09c2d531 | 253 | static unsigned __dm_get_module_param(unsigned *module_param, |
f4790826 MS |
254 | unsigned def, unsigned max) |
255 | { | |
09c2d531 MS |
256 | unsigned param = ACCESS_ONCE(*module_param); |
257 | unsigned modified_param = 0; | |
f4790826 | 258 | |
09c2d531 MS |
259 | if (!param) |
260 | modified_param = def; | |
261 | else if (param > max) | |
262 | modified_param = max; | |
f4790826 | 263 | |
09c2d531 MS |
264 | if (modified_param) { |
265 | (void)cmpxchg(module_param, param, modified_param); | |
266 | param = modified_param; | |
f4790826 MS |
267 | } |
268 | ||
09c2d531 | 269 | return param; |
f4790826 MS |
270 | } |
271 | ||
e8603136 MS |
272 | unsigned dm_get_reserved_bio_based_ios(void) |
273 | { | |
09c2d531 | 274 | return __dm_get_module_param(&reserved_bio_based_ios, |
e8603136 MS |
275 | RESERVED_BIO_BASED_IOS, RESERVED_MAX_IOS); |
276 | } | |
277 | EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); | |
278 | ||
f4790826 MS |
279 | unsigned dm_get_reserved_rq_based_ios(void) |
280 | { | |
09c2d531 | 281 | return __dm_get_module_param(&reserved_rq_based_ios, |
f4790826 MS |
282 | RESERVED_REQUEST_BASED_IOS, RESERVED_MAX_IOS); |
283 | } | |
284 | EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios); | |
285 | ||
1da177e4 LT |
286 | static int __init local_init(void) |
287 | { | |
51157b4a | 288 | int r = -ENOMEM; |
1da177e4 | 289 | |
1da177e4 | 290 | /* allocate a slab for the dm_ios */ |
028867ac | 291 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 | 292 | if (!_io_cache) |
51157b4a | 293 | return r; |
1da177e4 | 294 | |
8fbf26ad KU |
295 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
296 | if (!_rq_tio_cache) | |
dba14160 | 297 | goto out_free_io_cache; |
8fbf26ad | 298 | |
1ae49ea2 MS |
299 | _rq_cache = kmem_cache_create("dm_clone_request", sizeof(struct request), |
300 | __alignof__(struct request), 0, NULL); | |
301 | if (!_rq_cache) | |
302 | goto out_free_rq_tio_cache; | |
303 | ||
51e5b2bd | 304 | r = dm_uevent_init(); |
51157b4a | 305 | if (r) |
1ae49ea2 | 306 | goto out_free_rq_cache; |
51e5b2bd | 307 | |
acfe0ad7 MP |
308 | deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1); |
309 | if (!deferred_remove_workqueue) { | |
310 | r = -ENOMEM; | |
311 | goto out_uevent_exit; | |
312 | } | |
313 | ||
1da177e4 LT |
314 | _major = major; |
315 | r = register_blkdev(_major, _name); | |
51157b4a | 316 | if (r < 0) |
acfe0ad7 | 317 | goto out_free_workqueue; |
1da177e4 LT |
318 | |
319 | if (!_major) | |
320 | _major = r; | |
321 | ||
322 | return 0; | |
51157b4a | 323 | |
acfe0ad7 MP |
324 | out_free_workqueue: |
325 | destroy_workqueue(deferred_remove_workqueue); | |
51157b4a KU |
326 | out_uevent_exit: |
327 | dm_uevent_exit(); | |
1ae49ea2 MS |
328 | out_free_rq_cache: |
329 | kmem_cache_destroy(_rq_cache); | |
8fbf26ad KU |
330 | out_free_rq_tio_cache: |
331 | kmem_cache_destroy(_rq_tio_cache); | |
51157b4a KU |
332 | out_free_io_cache: |
333 | kmem_cache_destroy(_io_cache); | |
334 | ||
335 | return r; | |
1da177e4 LT |
336 | } |
337 | ||
338 | static void local_exit(void) | |
339 | { | |
2c140a24 | 340 | flush_scheduled_work(); |
acfe0ad7 | 341 | destroy_workqueue(deferred_remove_workqueue); |
2c140a24 | 342 | |
1ae49ea2 | 343 | kmem_cache_destroy(_rq_cache); |
8fbf26ad | 344 | kmem_cache_destroy(_rq_tio_cache); |
1da177e4 | 345 | kmem_cache_destroy(_io_cache); |
00d59405 | 346 | unregister_blkdev(_major, _name); |
51e5b2bd | 347 | dm_uevent_exit(); |
1da177e4 LT |
348 | |
349 | _major = 0; | |
350 | ||
351 | DMINFO("cleaned up"); | |
352 | } | |
353 | ||
b9249e55 | 354 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
355 | local_init, |
356 | dm_target_init, | |
357 | dm_linear_init, | |
358 | dm_stripe_init, | |
952b3557 | 359 | dm_io_init, |
945fa4d2 | 360 | dm_kcopyd_init, |
1da177e4 | 361 | dm_interface_init, |
fd2ed4d2 | 362 | dm_statistics_init, |
1da177e4 LT |
363 | }; |
364 | ||
b9249e55 | 365 | static void (*_exits[])(void) = { |
1da177e4 LT |
366 | local_exit, |
367 | dm_target_exit, | |
368 | dm_linear_exit, | |
369 | dm_stripe_exit, | |
952b3557 | 370 | dm_io_exit, |
945fa4d2 | 371 | dm_kcopyd_exit, |
1da177e4 | 372 | dm_interface_exit, |
fd2ed4d2 | 373 | dm_statistics_exit, |
1da177e4 LT |
374 | }; |
375 | ||
376 | static int __init dm_init(void) | |
377 | { | |
378 | const int count = ARRAY_SIZE(_inits); | |
379 | ||
380 | int r, i; | |
381 | ||
382 | for (i = 0; i < count; i++) { | |
383 | r = _inits[i](); | |
384 | if (r) | |
385 | goto bad; | |
386 | } | |
387 | ||
388 | return 0; | |
389 | ||
390 | bad: | |
391 | while (i--) | |
392 | _exits[i](); | |
393 | ||
394 | return r; | |
395 | } | |
396 | ||
397 | static void __exit dm_exit(void) | |
398 | { | |
399 | int i = ARRAY_SIZE(_exits); | |
400 | ||
401 | while (i--) | |
402 | _exits[i](); | |
d15b774c AK |
403 | |
404 | /* | |
405 | * Should be empty by this point. | |
406 | */ | |
d15b774c | 407 | idr_destroy(&_minor_idr); |
1da177e4 LT |
408 | } |
409 | ||
410 | /* | |
411 | * Block device functions | |
412 | */ | |
432a212c MA |
413 | int dm_deleting_md(struct mapped_device *md) |
414 | { | |
415 | return test_bit(DMF_DELETING, &md->flags); | |
416 | } | |
417 | ||
fe5f9f2c | 418 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
419 | { |
420 | struct mapped_device *md; | |
421 | ||
fba9f90e JM |
422 | spin_lock(&_minor_lock); |
423 | ||
fe5f9f2c | 424 | md = bdev->bd_disk->private_data; |
fba9f90e JM |
425 | if (!md) |
426 | goto out; | |
427 | ||
5c6bd75d | 428 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 429 | dm_deleting_md(md)) { |
fba9f90e JM |
430 | md = NULL; |
431 | goto out; | |
432 | } | |
433 | ||
1da177e4 | 434 | dm_get(md); |
5c6bd75d | 435 | atomic_inc(&md->open_count); |
fba9f90e JM |
436 | out: |
437 | spin_unlock(&_minor_lock); | |
438 | ||
439 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
440 | } |
441 | ||
db2a144b | 442 | static void dm_blk_close(struct gendisk *disk, fmode_t mode) |
1da177e4 | 443 | { |
63a4f065 | 444 | struct mapped_device *md; |
6e9624b8 | 445 | |
4a1aeb98 MB |
446 | spin_lock(&_minor_lock); |
447 | ||
63a4f065 MS |
448 | md = disk->private_data; |
449 | if (WARN_ON(!md)) | |
450 | goto out; | |
451 | ||
2c140a24 MP |
452 | if (atomic_dec_and_test(&md->open_count) && |
453 | (test_bit(DMF_DEFERRED_REMOVE, &md->flags))) | |
acfe0ad7 | 454 | queue_work(deferred_remove_workqueue, &deferred_remove_work); |
2c140a24 | 455 | |
1da177e4 | 456 | dm_put(md); |
63a4f065 | 457 | out: |
4a1aeb98 | 458 | spin_unlock(&_minor_lock); |
1da177e4 LT |
459 | } |
460 | ||
5c6bd75d AK |
461 | int dm_open_count(struct mapped_device *md) |
462 | { | |
463 | return atomic_read(&md->open_count); | |
464 | } | |
465 | ||
466 | /* | |
467 | * Guarantees nothing is using the device before it's deleted. | |
468 | */ | |
2c140a24 | 469 | int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred) |
5c6bd75d AK |
470 | { |
471 | int r = 0; | |
472 | ||
473 | spin_lock(&_minor_lock); | |
474 | ||
2c140a24 | 475 | if (dm_open_count(md)) { |
5c6bd75d | 476 | r = -EBUSY; |
2c140a24 MP |
477 | if (mark_deferred) |
478 | set_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
479 | } else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags)) | |
480 | r = -EEXIST; | |
5c6bd75d AK |
481 | else |
482 | set_bit(DMF_DELETING, &md->flags); | |
483 | ||
484 | spin_unlock(&_minor_lock); | |
485 | ||
486 | return r; | |
487 | } | |
488 | ||
2c140a24 MP |
489 | int dm_cancel_deferred_remove(struct mapped_device *md) |
490 | { | |
491 | int r = 0; | |
492 | ||
493 | spin_lock(&_minor_lock); | |
494 | ||
495 | if (test_bit(DMF_DELETING, &md->flags)) | |
496 | r = -EBUSY; | |
497 | else | |
498 | clear_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
499 | ||
500 | spin_unlock(&_minor_lock); | |
501 | ||
502 | return r; | |
503 | } | |
504 | ||
505 | static void do_deferred_remove(struct work_struct *w) | |
506 | { | |
507 | dm_deferred_remove(); | |
508 | } | |
509 | ||
fd2ed4d2 MP |
510 | sector_t dm_get_size(struct mapped_device *md) |
511 | { | |
512 | return get_capacity(md->disk); | |
513 | } | |
514 | ||
9974fa2c MS |
515 | struct request_queue *dm_get_md_queue(struct mapped_device *md) |
516 | { | |
517 | return md->queue; | |
518 | } | |
519 | ||
fd2ed4d2 MP |
520 | struct dm_stats *dm_get_stats(struct mapped_device *md) |
521 | { | |
522 | return &md->stats; | |
523 | } | |
524 | ||
3ac51e74 DW |
525 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
526 | { | |
527 | struct mapped_device *md = bdev->bd_disk->private_data; | |
528 | ||
529 | return dm_get_geometry(md, geo); | |
530 | } | |
531 | ||
fe5f9f2c | 532 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
aa129a22 MB |
533 | unsigned int cmd, unsigned long arg) |
534 | { | |
fe5f9f2c | 535 | struct mapped_device *md = bdev->bd_disk->private_data; |
83d5e5b0 | 536 | int srcu_idx; |
6c182cd8 | 537 | struct dm_table *map; |
aa129a22 MB |
538 | struct dm_target *tgt; |
539 | int r = -ENOTTY; | |
540 | ||
6c182cd8 | 541 | retry: |
83d5e5b0 MP |
542 | map = dm_get_live_table(md, &srcu_idx); |
543 | ||
aa129a22 MB |
544 | if (!map || !dm_table_get_size(map)) |
545 | goto out; | |
546 | ||
547 | /* We only support devices that have a single target */ | |
548 | if (dm_table_get_num_targets(map) != 1) | |
549 | goto out; | |
550 | ||
551 | tgt = dm_table_get_target(map, 0); | |
4d341d82 MS |
552 | if (!tgt->type->ioctl) |
553 | goto out; | |
aa129a22 | 554 | |
4f186f8b | 555 | if (dm_suspended_md(md)) { |
aa129a22 MB |
556 | r = -EAGAIN; |
557 | goto out; | |
558 | } | |
559 | ||
4d341d82 | 560 | r = tgt->type->ioctl(tgt, cmd, arg); |
aa129a22 MB |
561 | |
562 | out: | |
83d5e5b0 | 563 | dm_put_live_table(md, srcu_idx); |
aa129a22 | 564 | |
6c182cd8 HR |
565 | if (r == -ENOTCONN) { |
566 | msleep(10); | |
567 | goto retry; | |
568 | } | |
569 | ||
aa129a22 MB |
570 | return r; |
571 | } | |
572 | ||
028867ac | 573 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
574 | { |
575 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
576 | } | |
577 | ||
028867ac | 578 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
579 | { |
580 | mempool_free(io, md->io_pool); | |
581 | } | |
582 | ||
028867ac | 583 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 | 584 | { |
dba14160 | 585 | bio_put(&tio->clone); |
1da177e4 LT |
586 | } |
587 | ||
08885643 KU |
588 | static struct dm_rq_target_io *alloc_rq_tio(struct mapped_device *md, |
589 | gfp_t gfp_mask) | |
cec47e3d | 590 | { |
5f015204 | 591 | return mempool_alloc(md->io_pool, gfp_mask); |
cec47e3d KU |
592 | } |
593 | ||
594 | static void free_rq_tio(struct dm_rq_target_io *tio) | |
595 | { | |
5f015204 | 596 | mempool_free(tio, tio->md->io_pool); |
cec47e3d KU |
597 | } |
598 | ||
1ae49ea2 MS |
599 | static struct request *alloc_clone_request(struct mapped_device *md, |
600 | gfp_t gfp_mask) | |
601 | { | |
602 | return mempool_alloc(md->rq_pool, gfp_mask); | |
603 | } | |
604 | ||
605 | static void free_clone_request(struct mapped_device *md, struct request *rq) | |
606 | { | |
607 | mempool_free(rq, md->rq_pool); | |
608 | } | |
609 | ||
90abb8c4 KU |
610 | static int md_in_flight(struct mapped_device *md) |
611 | { | |
612 | return atomic_read(&md->pending[READ]) + | |
613 | atomic_read(&md->pending[WRITE]); | |
614 | } | |
615 | ||
3eaf840e JNN |
616 | static void start_io_acct(struct dm_io *io) |
617 | { | |
618 | struct mapped_device *md = io->md; | |
fd2ed4d2 | 619 | struct bio *bio = io->bio; |
c9959059 | 620 | int cpu; |
fd2ed4d2 | 621 | int rw = bio_data_dir(bio); |
3eaf840e JNN |
622 | |
623 | io->start_time = jiffies; | |
624 | ||
074a7aca TH |
625 | cpu = part_stat_lock(); |
626 | part_round_stats(cpu, &dm_disk(md)->part0); | |
627 | part_stat_unlock(); | |
1e9bb880 SL |
628 | atomic_set(&dm_disk(md)->part0.in_flight[rw], |
629 | atomic_inc_return(&md->pending[rw])); | |
fd2ed4d2 MP |
630 | |
631 | if (unlikely(dm_stats_used(&md->stats))) | |
4f024f37 | 632 | dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, |
fd2ed4d2 | 633 | bio_sectors(bio), false, 0, &io->stats_aux); |
3eaf840e JNN |
634 | } |
635 | ||
d221d2e7 | 636 | static void end_io_acct(struct dm_io *io) |
3eaf840e JNN |
637 | { |
638 | struct mapped_device *md = io->md; | |
639 | struct bio *bio = io->bio; | |
640 | unsigned long duration = jiffies - io->start_time; | |
18c0b223 | 641 | int pending; |
3eaf840e JNN |
642 | int rw = bio_data_dir(bio); |
643 | ||
18c0b223 | 644 | generic_end_io_acct(rw, &dm_disk(md)->part0, io->start_time); |
3eaf840e | 645 | |
fd2ed4d2 | 646 | if (unlikely(dm_stats_used(&md->stats))) |
4f024f37 | 647 | dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, |
fd2ed4d2 MP |
648 | bio_sectors(bio), true, duration, &io->stats_aux); |
649 | ||
af7e466a MP |
650 | /* |
651 | * After this is decremented the bio must not be touched if it is | |
d87f4c14 | 652 | * a flush. |
af7e466a | 653 | */ |
1e9bb880 SL |
654 | pending = atomic_dec_return(&md->pending[rw]); |
655 | atomic_set(&dm_disk(md)->part0.in_flight[rw], pending); | |
316d315b | 656 | pending += atomic_read(&md->pending[rw^0x1]); |
3eaf840e | 657 | |
d221d2e7 MP |
658 | /* nudge anyone waiting on suspend queue */ |
659 | if (!pending) | |
660 | wake_up(&md->wait); | |
3eaf840e JNN |
661 | } |
662 | ||
1da177e4 LT |
663 | /* |
664 | * Add the bio to the list of deferred io. | |
665 | */ | |
92c63902 | 666 | static void queue_io(struct mapped_device *md, struct bio *bio) |
1da177e4 | 667 | { |
05447420 | 668 | unsigned long flags; |
1da177e4 | 669 | |
05447420 | 670 | spin_lock_irqsave(&md->deferred_lock, flags); |
1da177e4 | 671 | bio_list_add(&md->deferred, bio); |
05447420 | 672 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
6a8736d1 | 673 | queue_work(md->wq, &md->work); |
1da177e4 LT |
674 | } |
675 | ||
676 | /* | |
677 | * Everyone (including functions in this file), should use this | |
678 | * function to access the md->map field, and make sure they call | |
83d5e5b0 | 679 | * dm_put_live_table() when finished. |
1da177e4 | 680 | */ |
83d5e5b0 | 681 | struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier) |
1da177e4 | 682 | { |
83d5e5b0 MP |
683 | *srcu_idx = srcu_read_lock(&md->io_barrier); |
684 | ||
685 | return srcu_dereference(md->map, &md->io_barrier); | |
686 | } | |
1da177e4 | 687 | |
83d5e5b0 MP |
688 | void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier) |
689 | { | |
690 | srcu_read_unlock(&md->io_barrier, srcu_idx); | |
691 | } | |
692 | ||
693 | void dm_sync_table(struct mapped_device *md) | |
694 | { | |
695 | synchronize_srcu(&md->io_barrier); | |
696 | synchronize_rcu_expedited(); | |
697 | } | |
698 | ||
699 | /* | |
700 | * A fast alternative to dm_get_live_table/dm_put_live_table. | |
701 | * The caller must not block between these two functions. | |
702 | */ | |
703 | static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU) | |
704 | { | |
705 | rcu_read_lock(); | |
706 | return rcu_dereference(md->map); | |
707 | } | |
1da177e4 | 708 | |
83d5e5b0 MP |
709 | static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU) |
710 | { | |
711 | rcu_read_unlock(); | |
1da177e4 LT |
712 | } |
713 | ||
86f1152b BM |
714 | /* |
715 | * Open a table device so we can use it as a map destination. | |
716 | */ | |
717 | static int open_table_device(struct table_device *td, dev_t dev, | |
718 | struct mapped_device *md) | |
719 | { | |
720 | static char *_claim_ptr = "I belong to device-mapper"; | |
721 | struct block_device *bdev; | |
722 | ||
723 | int r; | |
724 | ||
725 | BUG_ON(td->dm_dev.bdev); | |
726 | ||
727 | bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _claim_ptr); | |
728 | if (IS_ERR(bdev)) | |
729 | return PTR_ERR(bdev); | |
730 | ||
731 | r = bd_link_disk_holder(bdev, dm_disk(md)); | |
732 | if (r) { | |
733 | blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL); | |
734 | return r; | |
735 | } | |
736 | ||
737 | td->dm_dev.bdev = bdev; | |
738 | return 0; | |
739 | } | |
740 | ||
741 | /* | |
742 | * Close a table device that we've been using. | |
743 | */ | |
744 | static void close_table_device(struct table_device *td, struct mapped_device *md) | |
745 | { | |
746 | if (!td->dm_dev.bdev) | |
747 | return; | |
748 | ||
749 | bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md)); | |
750 | blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL); | |
751 | td->dm_dev.bdev = NULL; | |
752 | } | |
753 | ||
754 | static struct table_device *find_table_device(struct list_head *l, dev_t dev, | |
755 | fmode_t mode) { | |
756 | struct table_device *td; | |
757 | ||
758 | list_for_each_entry(td, l, list) | |
759 | if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode) | |
760 | return td; | |
761 | ||
762 | return NULL; | |
763 | } | |
764 | ||
765 | int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, | |
766 | struct dm_dev **result) { | |
767 | int r; | |
768 | struct table_device *td; | |
769 | ||
770 | mutex_lock(&md->table_devices_lock); | |
771 | td = find_table_device(&md->table_devices, dev, mode); | |
772 | if (!td) { | |
773 | td = kmalloc(sizeof(*td), GFP_KERNEL); | |
774 | if (!td) { | |
775 | mutex_unlock(&md->table_devices_lock); | |
776 | return -ENOMEM; | |
777 | } | |
778 | ||
779 | td->dm_dev.mode = mode; | |
780 | td->dm_dev.bdev = NULL; | |
781 | ||
782 | if ((r = open_table_device(td, dev, md))) { | |
783 | mutex_unlock(&md->table_devices_lock); | |
784 | kfree(td); | |
785 | return r; | |
786 | } | |
787 | ||
788 | format_dev_t(td->dm_dev.name, dev); | |
789 | ||
790 | atomic_set(&td->count, 0); | |
791 | list_add(&td->list, &md->table_devices); | |
792 | } | |
793 | atomic_inc(&td->count); | |
794 | mutex_unlock(&md->table_devices_lock); | |
795 | ||
796 | *result = &td->dm_dev; | |
797 | return 0; | |
798 | } | |
799 | EXPORT_SYMBOL_GPL(dm_get_table_device); | |
800 | ||
801 | void dm_put_table_device(struct mapped_device *md, struct dm_dev *d) | |
802 | { | |
803 | struct table_device *td = container_of(d, struct table_device, dm_dev); | |
804 | ||
805 | mutex_lock(&md->table_devices_lock); | |
806 | if (atomic_dec_and_test(&td->count)) { | |
807 | close_table_device(td, md); | |
808 | list_del(&td->list); | |
809 | kfree(td); | |
810 | } | |
811 | mutex_unlock(&md->table_devices_lock); | |
812 | } | |
813 | EXPORT_SYMBOL(dm_put_table_device); | |
814 | ||
815 | static void free_table_devices(struct list_head *devices) | |
816 | { | |
817 | struct list_head *tmp, *next; | |
818 | ||
819 | list_for_each_safe(tmp, next, devices) { | |
820 | struct table_device *td = list_entry(tmp, struct table_device, list); | |
821 | ||
822 | DMWARN("dm_destroy: %s still exists with %d references", | |
823 | td->dm_dev.name, atomic_read(&td->count)); | |
824 | kfree(td); | |
825 | } | |
826 | } | |
827 | ||
3ac51e74 DW |
828 | /* |
829 | * Get the geometry associated with a dm device | |
830 | */ | |
831 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
832 | { | |
833 | *geo = md->geometry; | |
834 | ||
835 | return 0; | |
836 | } | |
837 | ||
838 | /* | |
839 | * Set the geometry of a device. | |
840 | */ | |
841 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
842 | { | |
843 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
844 | ||
845 | if (geo->start > sz) { | |
846 | DMWARN("Start sector is beyond the geometry limits."); | |
847 | return -EINVAL; | |
848 | } | |
849 | ||
850 | md->geometry = *geo; | |
851 | ||
852 | return 0; | |
853 | } | |
854 | ||
1da177e4 LT |
855 | /*----------------------------------------------------------------- |
856 | * CRUD START: | |
857 | * A more elegant soln is in the works that uses the queue | |
858 | * merge fn, unfortunately there are a couple of changes to | |
859 | * the block layer that I want to make for this. So in the | |
860 | * interests of getting something for people to use I give | |
861 | * you this clearly demarcated crap. | |
862 | *---------------------------------------------------------------*/ | |
863 | ||
2e93ccc1 KU |
864 | static int __noflush_suspending(struct mapped_device *md) |
865 | { | |
866 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
867 | } | |
868 | ||
1da177e4 LT |
869 | /* |
870 | * Decrements the number of outstanding ios that a bio has been | |
871 | * cloned into, completing the original io if necc. | |
872 | */ | |
858119e1 | 873 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 874 | { |
2e93ccc1 | 875 | unsigned long flags; |
b35f8caa MB |
876 | int io_error; |
877 | struct bio *bio; | |
878 | struct mapped_device *md = io->md; | |
2e93ccc1 KU |
879 | |
880 | /* Push-back supersedes any I/O errors */ | |
f88fb981 KU |
881 | if (unlikely(error)) { |
882 | spin_lock_irqsave(&io->endio_lock, flags); | |
883 | if (!(io->error > 0 && __noflush_suspending(md))) | |
884 | io->error = error; | |
885 | spin_unlock_irqrestore(&io->endio_lock, flags); | |
886 | } | |
1da177e4 LT |
887 | |
888 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
889 | if (io->error == DM_ENDIO_REQUEUE) { |
890 | /* | |
891 | * Target requested pushing back the I/O. | |
2e93ccc1 | 892 | */ |
022c2611 | 893 | spin_lock_irqsave(&md->deferred_lock, flags); |
6a8736d1 TH |
894 | if (__noflush_suspending(md)) |
895 | bio_list_add_head(&md->deferred, io->bio); | |
896 | else | |
2e93ccc1 KU |
897 | /* noflush suspend was interrupted. */ |
898 | io->error = -EIO; | |
022c2611 | 899 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
2e93ccc1 KU |
900 | } |
901 | ||
b35f8caa MB |
902 | io_error = io->error; |
903 | bio = io->bio; | |
6a8736d1 TH |
904 | end_io_acct(io); |
905 | free_io(md, io); | |
906 | ||
907 | if (io_error == DM_ENDIO_REQUEUE) | |
908 | return; | |
2e93ccc1 | 909 | |
4f024f37 | 910 | if ((bio->bi_rw & REQ_FLUSH) && bio->bi_iter.bi_size) { |
af7e466a | 911 | /* |
6a8736d1 TH |
912 | * Preflush done for flush with data, reissue |
913 | * without REQ_FLUSH. | |
af7e466a | 914 | */ |
6a8736d1 TH |
915 | bio->bi_rw &= ~REQ_FLUSH; |
916 | queue_io(md, bio); | |
af7e466a | 917 | } else { |
b372d360 | 918 | /* done with normal IO or empty flush */ |
0a82a8d1 | 919 | trace_block_bio_complete(md->queue, bio, io_error); |
b372d360 | 920 | bio_endio(bio, io_error); |
b35f8caa | 921 | } |
1da177e4 LT |
922 | } |
923 | } | |
924 | ||
7eee4ae2 MS |
925 | static void disable_write_same(struct mapped_device *md) |
926 | { | |
927 | struct queue_limits *limits = dm_get_queue_limits(md); | |
928 | ||
929 | /* device doesn't really support WRITE SAME, disable it */ | |
930 | limits->max_write_same_sectors = 0; | |
931 | } | |
932 | ||
6712ecf8 | 933 | static void clone_endio(struct bio *bio, int error) |
1da177e4 | 934 | { |
5164bece | 935 | int r = error; |
bfc6d41c | 936 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
b35f8caa | 937 | struct dm_io *io = tio->io; |
9faf400f | 938 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
939 | dm_endio_fn endio = tio->ti->type->end_io; |
940 | ||
1da177e4 LT |
941 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
942 | error = -EIO; | |
943 | ||
944 | if (endio) { | |
7de3ee57 | 945 | r = endio(tio->ti, bio, error); |
2e93ccc1 KU |
946 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
947 | /* | |
948 | * error and requeue request are handled | |
949 | * in dec_pending(). | |
950 | */ | |
1da177e4 | 951 | error = r; |
45cbcd79 KU |
952 | else if (r == DM_ENDIO_INCOMPLETE) |
953 | /* The target will handle the io */ | |
6712ecf8 | 954 | return; |
45cbcd79 KU |
955 | else if (r) { |
956 | DMWARN("unimplemented target endio return value: %d", r); | |
957 | BUG(); | |
958 | } | |
1da177e4 LT |
959 | } |
960 | ||
7eee4ae2 MS |
961 | if (unlikely(r == -EREMOTEIO && (bio->bi_rw & REQ_WRITE_SAME) && |
962 | !bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors)) | |
963 | disable_write_same(md); | |
964 | ||
9faf400f | 965 | free_tio(md, tio); |
b35f8caa | 966 | dec_pending(io, error); |
1da177e4 LT |
967 | } |
968 | ||
cec47e3d KU |
969 | /* |
970 | * Partial completion handling for request-based dm | |
971 | */ | |
972 | static void end_clone_bio(struct bio *clone, int error) | |
973 | { | |
bfc6d41c MP |
974 | struct dm_rq_clone_bio_info *info = |
975 | container_of(clone, struct dm_rq_clone_bio_info, clone); | |
cec47e3d KU |
976 | struct dm_rq_target_io *tio = info->tio; |
977 | struct bio *bio = info->orig; | |
4f024f37 | 978 | unsigned int nr_bytes = info->orig->bi_iter.bi_size; |
cec47e3d KU |
979 | |
980 | bio_put(clone); | |
981 | ||
982 | if (tio->error) | |
983 | /* | |
984 | * An error has already been detected on the request. | |
985 | * Once error occurred, just let clone->end_io() handle | |
986 | * the remainder. | |
987 | */ | |
988 | return; | |
989 | else if (error) { | |
990 | /* | |
991 | * Don't notice the error to the upper layer yet. | |
992 | * The error handling decision is made by the target driver, | |
993 | * when the request is completed. | |
994 | */ | |
995 | tio->error = error; | |
996 | return; | |
997 | } | |
998 | ||
999 | /* | |
1000 | * I/O for the bio successfully completed. | |
1001 | * Notice the data completion to the upper layer. | |
1002 | */ | |
1003 | ||
1004 | /* | |
1005 | * bios are processed from the head of the list. | |
1006 | * So the completing bio should always be rq->bio. | |
1007 | * If it's not, something wrong is happening. | |
1008 | */ | |
1009 | if (tio->orig->bio != bio) | |
1010 | DMERR("bio completion is going in the middle of the request"); | |
1011 | ||
1012 | /* | |
1013 | * Update the original request. | |
1014 | * Do not use blk_end_request() here, because it may complete | |
1015 | * the original request before the clone, and break the ordering. | |
1016 | */ | |
1017 | blk_update_request(tio->orig, 0, nr_bytes); | |
1018 | } | |
1019 | ||
1020 | /* | |
1021 | * Don't touch any member of the md after calling this function because | |
1022 | * the md may be freed in dm_put() at the end of this function. | |
1023 | * Or do dm_get() before calling this function and dm_put() later. | |
1024 | */ | |
466d89a6 | 1025 | static void rq_completed(struct mapped_device *md, int rw, bool run_queue) |
cec47e3d | 1026 | { |
9a0e609e MS |
1027 | int nr_requests_pending; |
1028 | ||
b4324fee | 1029 | atomic_dec(&md->pending[rw]); |
cec47e3d KU |
1030 | |
1031 | /* nudge anyone waiting on suspend queue */ | |
9a0e609e MS |
1032 | nr_requests_pending = md_in_flight(md); |
1033 | if (!nr_requests_pending) | |
cec47e3d KU |
1034 | wake_up(&md->wait); |
1035 | ||
a8c32a5c JA |
1036 | /* |
1037 | * Run this off this callpath, as drivers could invoke end_io while | |
1038 | * inside their request_fn (and holding the queue lock). Calling | |
1039 | * back into ->request_fn() could deadlock attempting to grab the | |
1040 | * queue lock again. | |
1041 | */ | |
9a0e609e MS |
1042 | if (run_queue) { |
1043 | if (!nr_requests_pending || | |
1044 | (nr_requests_pending >= md->queue->nr_congestion_on)) | |
1045 | blk_run_queue_async(md->queue); | |
1046 | } | |
cec47e3d KU |
1047 | |
1048 | /* | |
1049 | * dm_put() must be at the end of this function. See the comment above | |
1050 | */ | |
1051 | dm_put(md); | |
1052 | } | |
1053 | ||
a77e28c7 KU |
1054 | static void free_rq_clone(struct request *clone) |
1055 | { | |
1056 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1057 | ||
1058 | blk_rq_unprep_clone(clone); | |
e5863d9a MS |
1059 | if (clone->q && clone->q->mq_ops) |
1060 | tio->ti->type->release_clone_rq(clone); | |
1061 | else | |
1062 | free_clone_request(tio->md, clone); | |
a77e28c7 KU |
1063 | free_rq_tio(tio); |
1064 | } | |
1065 | ||
980691e5 KU |
1066 | /* |
1067 | * Complete the clone and the original request. | |
466d89a6 KB |
1068 | * Must be called without clone's queue lock held, |
1069 | * see end_clone_request() for more details. | |
980691e5 KU |
1070 | */ |
1071 | static void dm_end_request(struct request *clone, int error) | |
1072 | { | |
1073 | int rw = rq_data_dir(clone); | |
1074 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1075 | struct mapped_device *md = tio->md; | |
1076 | struct request *rq = tio->orig; | |
1077 | ||
29e4013d | 1078 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
980691e5 KU |
1079 | rq->errors = clone->errors; |
1080 | rq->resid_len = clone->resid_len; | |
1081 | ||
1082 | if (rq->sense) | |
1083 | /* | |
1084 | * We are using the sense buffer of the original | |
1085 | * request. | |
1086 | * So setting the length of the sense data is enough. | |
1087 | */ | |
1088 | rq->sense_len = clone->sense_len; | |
1089 | } | |
1090 | ||
1091 | free_rq_clone(clone); | |
29e4013d TH |
1092 | blk_end_request_all(rq, error); |
1093 | rq_completed(md, rw, true); | |
980691e5 KU |
1094 | } |
1095 | ||
cec47e3d KU |
1096 | static void dm_unprep_request(struct request *rq) |
1097 | { | |
466d89a6 KB |
1098 | struct dm_rq_target_io *tio = rq->special; |
1099 | struct request *clone = tio->clone; | |
cec47e3d KU |
1100 | |
1101 | rq->special = NULL; | |
1102 | rq->cmd_flags &= ~REQ_DONTPREP; | |
1103 | ||
e5863d9a MS |
1104 | if (clone) |
1105 | free_rq_clone(clone); | |
cec47e3d KU |
1106 | } |
1107 | ||
1108 | /* | |
1109 | * Requeue the original request of a clone. | |
1110 | */ | |
466d89a6 KB |
1111 | static void dm_requeue_unmapped_original_request(struct mapped_device *md, |
1112 | struct request *rq) | |
cec47e3d | 1113 | { |
466d89a6 | 1114 | int rw = rq_data_dir(rq); |
cec47e3d KU |
1115 | struct request_queue *q = rq->q; |
1116 | unsigned long flags; | |
1117 | ||
1118 | dm_unprep_request(rq); | |
1119 | ||
1120 | spin_lock_irqsave(q->queue_lock, flags); | |
cec47e3d KU |
1121 | blk_requeue_request(q, rq); |
1122 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1123 | ||
466d89a6 KB |
1124 | rq_completed(md, rw, false); |
1125 | } | |
1126 | ||
1127 | static void dm_requeue_unmapped_request(struct request *clone) | |
1128 | { | |
1129 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1130 | ||
1131 | dm_requeue_unmapped_original_request(tio->md, tio->orig); | |
cec47e3d | 1132 | } |
cec47e3d KU |
1133 | |
1134 | static void __stop_queue(struct request_queue *q) | |
1135 | { | |
1136 | blk_stop_queue(q); | |
1137 | } | |
1138 | ||
1139 | static void stop_queue(struct request_queue *q) | |
1140 | { | |
1141 | unsigned long flags; | |
1142 | ||
1143 | spin_lock_irqsave(q->queue_lock, flags); | |
1144 | __stop_queue(q); | |
1145 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1146 | } | |
1147 | ||
1148 | static void __start_queue(struct request_queue *q) | |
1149 | { | |
1150 | if (blk_queue_stopped(q)) | |
1151 | blk_start_queue(q); | |
1152 | } | |
1153 | ||
1154 | static void start_queue(struct request_queue *q) | |
1155 | { | |
1156 | unsigned long flags; | |
1157 | ||
1158 | spin_lock_irqsave(q->queue_lock, flags); | |
1159 | __start_queue(q); | |
1160 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1161 | } | |
1162 | ||
11a68244 | 1163 | static void dm_done(struct request *clone, int error, bool mapped) |
cec47e3d | 1164 | { |
11a68244 | 1165 | int r = error; |
cec47e3d | 1166 | struct dm_rq_target_io *tio = clone->end_io_data; |
ba1cbad9 | 1167 | dm_request_endio_fn rq_end_io = NULL; |
cec47e3d | 1168 | |
ba1cbad9 MS |
1169 | if (tio->ti) { |
1170 | rq_end_io = tio->ti->type->rq_end_io; | |
1171 | ||
1172 | if (mapped && rq_end_io) | |
1173 | r = rq_end_io(tio->ti, clone, error, &tio->info); | |
1174 | } | |
cec47e3d | 1175 | |
7eee4ae2 MS |
1176 | if (unlikely(r == -EREMOTEIO && (clone->cmd_flags & REQ_WRITE_SAME) && |
1177 | !clone->q->limits.max_write_same_sectors)) | |
1178 | disable_write_same(tio->md); | |
1179 | ||
11a68244 | 1180 | if (r <= 0) |
cec47e3d | 1181 | /* The target wants to complete the I/O */ |
11a68244 KU |
1182 | dm_end_request(clone, r); |
1183 | else if (r == DM_ENDIO_INCOMPLETE) | |
cec47e3d KU |
1184 | /* The target will handle the I/O */ |
1185 | return; | |
11a68244 | 1186 | else if (r == DM_ENDIO_REQUEUE) |
cec47e3d KU |
1187 | /* The target wants to requeue the I/O */ |
1188 | dm_requeue_unmapped_request(clone); | |
1189 | else { | |
11a68244 | 1190 | DMWARN("unimplemented target endio return value: %d", r); |
cec47e3d KU |
1191 | BUG(); |
1192 | } | |
1193 | } | |
1194 | ||
11a68244 KU |
1195 | /* |
1196 | * Request completion handler for request-based dm | |
1197 | */ | |
1198 | static void dm_softirq_done(struct request *rq) | |
1199 | { | |
1200 | bool mapped = true; | |
466d89a6 KB |
1201 | struct dm_rq_target_io *tio = rq->special; |
1202 | struct request *clone = tio->clone; | |
11a68244 | 1203 | |
e5863d9a MS |
1204 | if (!clone) { |
1205 | blk_end_request_all(rq, tio->error); | |
1206 | rq_completed(tio->md, rq_data_dir(rq), false); | |
1207 | free_rq_tio(tio); | |
1208 | return; | |
1209 | } | |
11a68244 KU |
1210 | |
1211 | if (rq->cmd_flags & REQ_FAILED) | |
1212 | mapped = false; | |
1213 | ||
1214 | dm_done(clone, tio->error, mapped); | |
1215 | } | |
1216 | ||
cec47e3d KU |
1217 | /* |
1218 | * Complete the clone and the original request with the error status | |
1219 | * through softirq context. | |
1220 | */ | |
466d89a6 | 1221 | static void dm_complete_request(struct request *rq, int error) |
cec47e3d | 1222 | { |
466d89a6 | 1223 | struct dm_rq_target_io *tio = rq->special; |
cec47e3d KU |
1224 | |
1225 | tio->error = error; | |
cec47e3d KU |
1226 | blk_complete_request(rq); |
1227 | } | |
1228 | ||
1229 | /* | |
1230 | * Complete the not-mapped clone and the original request with the error status | |
1231 | * through softirq context. | |
1232 | * Target's rq_end_io() function isn't called. | |
e5863d9a | 1233 | * This may be used when the target's map_rq() or clone_and_map_rq() functions fail. |
cec47e3d | 1234 | */ |
466d89a6 | 1235 | static void dm_kill_unmapped_request(struct request *rq, int error) |
cec47e3d | 1236 | { |
cec47e3d | 1237 | rq->cmd_flags |= REQ_FAILED; |
466d89a6 | 1238 | dm_complete_request(rq, error); |
cec47e3d | 1239 | } |
cec47e3d KU |
1240 | |
1241 | /* | |
466d89a6 | 1242 | * Called with the clone's queue lock held |
cec47e3d KU |
1243 | */ |
1244 | static void end_clone_request(struct request *clone, int error) | |
1245 | { | |
466d89a6 KB |
1246 | struct dm_rq_target_io *tio = clone->end_io_data; |
1247 | ||
e5863d9a MS |
1248 | if (!clone->q->mq_ops) { |
1249 | /* | |
1250 | * For just cleaning up the information of the queue in which | |
1251 | * the clone was dispatched. | |
1252 | * The clone is *NOT* freed actually here because it is alloced | |
1253 | * from dm own mempool (REQ_ALLOCED isn't set). | |
1254 | */ | |
1255 | __blk_put_request(clone->q, clone); | |
1256 | } | |
cec47e3d KU |
1257 | |
1258 | /* | |
1259 | * Actual request completion is done in a softirq context which doesn't | |
466d89a6 | 1260 | * hold the clone's queue lock. Otherwise, deadlock could occur because: |
cec47e3d KU |
1261 | * - another request may be submitted by the upper level driver |
1262 | * of the stacking during the completion | |
1263 | * - the submission which requires queue lock may be done | |
466d89a6 | 1264 | * against this clone's queue |
cec47e3d | 1265 | */ |
466d89a6 | 1266 | dm_complete_request(tio->orig, error); |
cec47e3d KU |
1267 | } |
1268 | ||
56a67df7 MS |
1269 | /* |
1270 | * Return maximum size of I/O possible at the supplied sector up to the current | |
1271 | * target boundary. | |
1272 | */ | |
1273 | static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti) | |
1274 | { | |
1275 | sector_t target_offset = dm_target_offset(ti, sector); | |
1276 | ||
1277 | return ti->len - target_offset; | |
1278 | } | |
1279 | ||
1280 | static sector_t max_io_len(sector_t sector, struct dm_target *ti) | |
1da177e4 | 1281 | { |
56a67df7 | 1282 | sector_t len = max_io_len_target_boundary(sector, ti); |
542f9038 | 1283 | sector_t offset, max_len; |
1da177e4 LT |
1284 | |
1285 | /* | |
542f9038 | 1286 | * Does the target need to split even further? |
1da177e4 | 1287 | */ |
542f9038 MS |
1288 | if (ti->max_io_len) { |
1289 | offset = dm_target_offset(ti, sector); | |
1290 | if (unlikely(ti->max_io_len & (ti->max_io_len - 1))) | |
1291 | max_len = sector_div(offset, ti->max_io_len); | |
1292 | else | |
1293 | max_len = offset & (ti->max_io_len - 1); | |
1294 | max_len = ti->max_io_len - max_len; | |
1295 | ||
1296 | if (len > max_len) | |
1297 | len = max_len; | |
1da177e4 LT |
1298 | } |
1299 | ||
1300 | return len; | |
1301 | } | |
1302 | ||
542f9038 MS |
1303 | int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) |
1304 | { | |
1305 | if (len > UINT_MAX) { | |
1306 | DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)", | |
1307 | (unsigned long long)len, UINT_MAX); | |
1308 | ti->error = "Maximum size of target IO is too large"; | |
1309 | return -EINVAL; | |
1310 | } | |
1311 | ||
1312 | ti->max_io_len = (uint32_t) len; | |
1313 | ||
1314 | return 0; | |
1315 | } | |
1316 | EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); | |
1317 | ||
1dd40c3e MP |
1318 | /* |
1319 | * A target may call dm_accept_partial_bio only from the map routine. It is | |
1320 | * allowed for all bio types except REQ_FLUSH. | |
1321 | * | |
1322 | * dm_accept_partial_bio informs the dm that the target only wants to process | |
1323 | * additional n_sectors sectors of the bio and the rest of the data should be | |
1324 | * sent in a next bio. | |
1325 | * | |
1326 | * A diagram that explains the arithmetics: | |
1327 | * +--------------------+---------------+-------+ | |
1328 | * | 1 | 2 | 3 | | |
1329 | * +--------------------+---------------+-------+ | |
1330 | * | |
1331 | * <-------------- *tio->len_ptr ---------------> | |
1332 | * <------- bi_size -------> | |
1333 | * <-- n_sectors --> | |
1334 | * | |
1335 | * Region 1 was already iterated over with bio_advance or similar function. | |
1336 | * (it may be empty if the target doesn't use bio_advance) | |
1337 | * Region 2 is the remaining bio size that the target wants to process. | |
1338 | * (it may be empty if region 1 is non-empty, although there is no reason | |
1339 | * to make it empty) | |
1340 | * The target requires that region 3 is to be sent in the next bio. | |
1341 | * | |
1342 | * If the target wants to receive multiple copies of the bio (via num_*bios, etc), | |
1343 | * the partially processed part (the sum of regions 1+2) must be the same for all | |
1344 | * copies of the bio. | |
1345 | */ | |
1346 | void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) | |
1347 | { | |
1348 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); | |
1349 | unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; | |
1350 | BUG_ON(bio->bi_rw & REQ_FLUSH); | |
1351 | BUG_ON(bi_size > *tio->len_ptr); | |
1352 | BUG_ON(n_sectors > bi_size); | |
1353 | *tio->len_ptr -= bi_size - n_sectors; | |
1354 | bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT; | |
1355 | } | |
1356 | EXPORT_SYMBOL_GPL(dm_accept_partial_bio); | |
1357 | ||
bd2a49b8 | 1358 | static void __map_bio(struct dm_target_io *tio) |
1da177e4 LT |
1359 | { |
1360 | int r; | |
2056a782 | 1361 | sector_t sector; |
9faf400f | 1362 | struct mapped_device *md; |
dba14160 | 1363 | struct bio *clone = &tio->clone; |
bd2a49b8 | 1364 | struct dm_target *ti = tio->ti; |
1da177e4 | 1365 | |
1da177e4 | 1366 | clone->bi_end_io = clone_endio; |
1da177e4 LT |
1367 | |
1368 | /* | |
1369 | * Map the clone. If r == 0 we don't need to do | |
1370 | * anything, the target has assumed ownership of | |
1371 | * this io. | |
1372 | */ | |
1373 | atomic_inc(&tio->io->io_count); | |
4f024f37 | 1374 | sector = clone->bi_iter.bi_sector; |
7de3ee57 | 1375 | r = ti->type->map(ti, clone); |
45cbcd79 | 1376 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 1377 | /* the bio has been remapped so dispatch it */ |
2056a782 | 1378 | |
d07335e5 MS |
1379 | trace_block_bio_remap(bdev_get_queue(clone->bi_bdev), clone, |
1380 | tio->io->bio->bi_bdev->bd_dev, sector); | |
2056a782 | 1381 | |
1da177e4 | 1382 | generic_make_request(clone); |
2e93ccc1 KU |
1383 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
1384 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
1385 | md = tio->io->md; |
1386 | dec_pending(tio->io, r); | |
9faf400f | 1387 | free_tio(md, tio); |
45cbcd79 KU |
1388 | } else if (r) { |
1389 | DMWARN("unimplemented target map return value: %d", r); | |
1390 | BUG(); | |
1da177e4 LT |
1391 | } |
1392 | } | |
1393 | ||
1394 | struct clone_info { | |
1395 | struct mapped_device *md; | |
1396 | struct dm_table *map; | |
1397 | struct bio *bio; | |
1398 | struct dm_io *io; | |
1399 | sector_t sector; | |
e0d6609a | 1400 | unsigned sector_count; |
1da177e4 LT |
1401 | }; |
1402 | ||
e0d6609a | 1403 | static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) |
bd2a49b8 | 1404 | { |
4f024f37 KO |
1405 | bio->bi_iter.bi_sector = sector; |
1406 | bio->bi_iter.bi_size = to_bytes(len); | |
1da177e4 LT |
1407 | } |
1408 | ||
1409 | /* | |
1410 | * Creates a bio that consists of range of complete bvecs. | |
1411 | */ | |
dba14160 | 1412 | static void clone_bio(struct dm_target_io *tio, struct bio *bio, |
1c3b13e6 | 1413 | sector_t sector, unsigned len) |
1da177e4 | 1414 | { |
dba14160 | 1415 | struct bio *clone = &tio->clone; |
1da177e4 | 1416 | |
1c3b13e6 KO |
1417 | __bio_clone_fast(clone, bio); |
1418 | ||
1419 | if (bio_integrity(bio)) | |
1420 | bio_integrity_clone(clone, bio, GFP_NOIO); | |
bd2a49b8 | 1421 | |
1c3b13e6 KO |
1422 | bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); |
1423 | clone->bi_iter.bi_size = to_bytes(len); | |
1424 | ||
1425 | if (bio_integrity(bio)) | |
1426 | bio_integrity_trim(clone, 0, len); | |
1da177e4 LT |
1427 | } |
1428 | ||
9015df24 | 1429 | static struct dm_target_io *alloc_tio(struct clone_info *ci, |
99778273 | 1430 | struct dm_target *ti, |
55a62eef | 1431 | unsigned target_bio_nr) |
f9ab94ce | 1432 | { |
dba14160 MP |
1433 | struct dm_target_io *tio; |
1434 | struct bio *clone; | |
1435 | ||
99778273 | 1436 | clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs); |
dba14160 | 1437 | tio = container_of(clone, struct dm_target_io, clone); |
f9ab94ce MP |
1438 | |
1439 | tio->io = ci->io; | |
1440 | tio->ti = ti; | |
55a62eef | 1441 | tio->target_bio_nr = target_bio_nr; |
9015df24 AK |
1442 | |
1443 | return tio; | |
1444 | } | |
1445 | ||
14fe594d AK |
1446 | static void __clone_and_map_simple_bio(struct clone_info *ci, |
1447 | struct dm_target *ti, | |
1dd40c3e | 1448 | unsigned target_bio_nr, unsigned *len) |
9015df24 | 1449 | { |
99778273 | 1450 | struct dm_target_io *tio = alloc_tio(ci, ti, target_bio_nr); |
dba14160 | 1451 | struct bio *clone = &tio->clone; |
9015df24 | 1452 | |
1dd40c3e MP |
1453 | tio->len_ptr = len; |
1454 | ||
99778273 | 1455 | __bio_clone_fast(clone, ci->bio); |
bd2a49b8 | 1456 | if (len) |
1dd40c3e | 1457 | bio_setup_sector(clone, ci->sector, *len); |
f9ab94ce | 1458 | |
bd2a49b8 | 1459 | __map_bio(tio); |
f9ab94ce MP |
1460 | } |
1461 | ||
14fe594d | 1462 | static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, |
1dd40c3e | 1463 | unsigned num_bios, unsigned *len) |
06a426ce | 1464 | { |
55a62eef | 1465 | unsigned target_bio_nr; |
06a426ce | 1466 | |
55a62eef | 1467 | for (target_bio_nr = 0; target_bio_nr < num_bios; target_bio_nr++) |
14fe594d | 1468 | __clone_and_map_simple_bio(ci, ti, target_bio_nr, len); |
06a426ce MS |
1469 | } |
1470 | ||
14fe594d | 1471 | static int __send_empty_flush(struct clone_info *ci) |
f9ab94ce | 1472 | { |
06a426ce | 1473 | unsigned target_nr = 0; |
f9ab94ce MP |
1474 | struct dm_target *ti; |
1475 | ||
b372d360 | 1476 | BUG_ON(bio_has_data(ci->bio)); |
f9ab94ce | 1477 | while ((ti = dm_table_get_target(ci->map, target_nr++))) |
1dd40c3e | 1478 | __send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL); |
f9ab94ce | 1479 | |
f9ab94ce MP |
1480 | return 0; |
1481 | } | |
1482 | ||
e4c93811 | 1483 | static void __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, |
1dd40c3e | 1484 | sector_t sector, unsigned *len) |
5ae89a87 | 1485 | { |
dba14160 | 1486 | struct bio *bio = ci->bio; |
5ae89a87 | 1487 | struct dm_target_io *tio; |
b0d8ed4d AK |
1488 | unsigned target_bio_nr; |
1489 | unsigned num_target_bios = 1; | |
5ae89a87 | 1490 | |
b0d8ed4d AK |
1491 | /* |
1492 | * Does the target want to receive duplicate copies of the bio? | |
1493 | */ | |
1494 | if (bio_data_dir(bio) == WRITE && ti->num_write_bios) | |
1495 | num_target_bios = ti->num_write_bios(ti, bio); | |
e4c93811 | 1496 | |
b0d8ed4d | 1497 | for (target_bio_nr = 0; target_bio_nr < num_target_bios; target_bio_nr++) { |
99778273 | 1498 | tio = alloc_tio(ci, ti, target_bio_nr); |
1dd40c3e MP |
1499 | tio->len_ptr = len; |
1500 | clone_bio(tio, bio, sector, *len); | |
b0d8ed4d AK |
1501 | __map_bio(tio); |
1502 | } | |
5ae89a87 MS |
1503 | } |
1504 | ||
55a62eef | 1505 | typedef unsigned (*get_num_bios_fn)(struct dm_target *ti); |
23508a96 | 1506 | |
55a62eef | 1507 | static unsigned get_num_discard_bios(struct dm_target *ti) |
23508a96 | 1508 | { |
55a62eef | 1509 | return ti->num_discard_bios; |
23508a96 MS |
1510 | } |
1511 | ||
55a62eef | 1512 | static unsigned get_num_write_same_bios(struct dm_target *ti) |
23508a96 | 1513 | { |
55a62eef | 1514 | return ti->num_write_same_bios; |
23508a96 MS |
1515 | } |
1516 | ||
1517 | typedef bool (*is_split_required_fn)(struct dm_target *ti); | |
1518 | ||
1519 | static bool is_split_required_for_discard(struct dm_target *ti) | |
1520 | { | |
55a62eef | 1521 | return ti->split_discard_bios; |
23508a96 MS |
1522 | } |
1523 | ||
14fe594d AK |
1524 | static int __send_changing_extent_only(struct clone_info *ci, |
1525 | get_num_bios_fn get_num_bios, | |
1526 | is_split_required_fn is_split_required) | |
5ae89a87 MS |
1527 | { |
1528 | struct dm_target *ti; | |
e0d6609a | 1529 | unsigned len; |
55a62eef | 1530 | unsigned num_bios; |
5ae89a87 | 1531 | |
a79245b3 MS |
1532 | do { |
1533 | ti = dm_table_find_target(ci->map, ci->sector); | |
1534 | if (!dm_target_is_valid(ti)) | |
1535 | return -EIO; | |
5ae89a87 | 1536 | |
5ae89a87 | 1537 | /* |
23508a96 MS |
1538 | * Even though the device advertised support for this type of |
1539 | * request, that does not mean every target supports it, and | |
936688d7 | 1540 | * reconfiguration might also have changed that since the |
a79245b3 | 1541 | * check was performed. |
5ae89a87 | 1542 | */ |
55a62eef AK |
1543 | num_bios = get_num_bios ? get_num_bios(ti) : 0; |
1544 | if (!num_bios) | |
a79245b3 | 1545 | return -EOPNOTSUPP; |
5ae89a87 | 1546 | |
23508a96 | 1547 | if (is_split_required && !is_split_required(ti)) |
e0d6609a | 1548 | len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); |
7acf0277 | 1549 | else |
e0d6609a | 1550 | len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti)); |
06a426ce | 1551 | |
1dd40c3e | 1552 | __send_duplicate_bios(ci, ti, num_bios, &len); |
a79245b3 MS |
1553 | |
1554 | ci->sector += len; | |
1555 | } while (ci->sector_count -= len); | |
5ae89a87 MS |
1556 | |
1557 | return 0; | |
1558 | } | |
1559 | ||
14fe594d | 1560 | static int __send_discard(struct clone_info *ci) |
23508a96 | 1561 | { |
14fe594d AK |
1562 | return __send_changing_extent_only(ci, get_num_discard_bios, |
1563 | is_split_required_for_discard); | |
23508a96 MS |
1564 | } |
1565 | ||
14fe594d | 1566 | static int __send_write_same(struct clone_info *ci) |
23508a96 | 1567 | { |
14fe594d | 1568 | return __send_changing_extent_only(ci, get_num_write_same_bios, NULL); |
23508a96 MS |
1569 | } |
1570 | ||
e4c93811 AK |
1571 | /* |
1572 | * Select the correct strategy for processing a non-flush bio. | |
1573 | */ | |
14fe594d | 1574 | static int __split_and_process_non_flush(struct clone_info *ci) |
1da177e4 | 1575 | { |
dba14160 | 1576 | struct bio *bio = ci->bio; |
512875bd | 1577 | struct dm_target *ti; |
1c3b13e6 | 1578 | unsigned len; |
1da177e4 | 1579 | |
5ae89a87 | 1580 | if (unlikely(bio->bi_rw & REQ_DISCARD)) |
14fe594d | 1581 | return __send_discard(ci); |
23508a96 | 1582 | else if (unlikely(bio->bi_rw & REQ_WRITE_SAME)) |
14fe594d | 1583 | return __send_write_same(ci); |
5ae89a87 | 1584 | |
512875bd JN |
1585 | ti = dm_table_find_target(ci->map, ci->sector); |
1586 | if (!dm_target_is_valid(ti)) | |
1587 | return -EIO; | |
1588 | ||
1c3b13e6 | 1589 | len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count); |
1da177e4 | 1590 | |
1dd40c3e | 1591 | __clone_and_map_data_bio(ci, ti, ci->sector, &len); |
1da177e4 | 1592 | |
1c3b13e6 KO |
1593 | ci->sector += len; |
1594 | ci->sector_count -= len; | |
1da177e4 | 1595 | |
1c3b13e6 | 1596 | return 0; |
1da177e4 LT |
1597 | } |
1598 | ||
1599 | /* | |
14fe594d | 1600 | * Entry point to split a bio into clones and submit them to the targets. |
1da177e4 | 1601 | */ |
83d5e5b0 MP |
1602 | static void __split_and_process_bio(struct mapped_device *md, |
1603 | struct dm_table *map, struct bio *bio) | |
1da177e4 LT |
1604 | { |
1605 | struct clone_info ci; | |
512875bd | 1606 | int error = 0; |
1da177e4 | 1607 | |
83d5e5b0 | 1608 | if (unlikely(!map)) { |
6a8736d1 | 1609 | bio_io_error(bio); |
f0b9a450 MP |
1610 | return; |
1611 | } | |
692d0eb9 | 1612 | |
83d5e5b0 | 1613 | ci.map = map; |
1da177e4 | 1614 | ci.md = md; |
1da177e4 LT |
1615 | ci.io = alloc_io(md); |
1616 | ci.io->error = 0; | |
1617 | atomic_set(&ci.io->io_count, 1); | |
1618 | ci.io->bio = bio; | |
1619 | ci.io->md = md; | |
f88fb981 | 1620 | spin_lock_init(&ci.io->endio_lock); |
4f024f37 | 1621 | ci.sector = bio->bi_iter.bi_sector; |
1da177e4 | 1622 | |
3eaf840e | 1623 | start_io_acct(ci.io); |
bd2a49b8 | 1624 | |
b372d360 MS |
1625 | if (bio->bi_rw & REQ_FLUSH) { |
1626 | ci.bio = &ci.md->flush_bio; | |
1627 | ci.sector_count = 0; | |
14fe594d | 1628 | error = __send_empty_flush(&ci); |
b372d360 MS |
1629 | /* dec_pending submits any data associated with flush */ |
1630 | } else { | |
6a8736d1 | 1631 | ci.bio = bio; |
d87f4c14 | 1632 | ci.sector_count = bio_sectors(bio); |
b372d360 | 1633 | while (ci.sector_count && !error) |
14fe594d | 1634 | error = __split_and_process_non_flush(&ci); |
d87f4c14 | 1635 | } |
1da177e4 LT |
1636 | |
1637 | /* drop the extra reference count */ | |
512875bd | 1638 | dec_pending(ci.io, error); |
1da177e4 LT |
1639 | } |
1640 | /*----------------------------------------------------------------- | |
1641 | * CRUD END | |
1642 | *---------------------------------------------------------------*/ | |
1643 | ||
f6fccb12 MB |
1644 | static int dm_merge_bvec(struct request_queue *q, |
1645 | struct bvec_merge_data *bvm, | |
1646 | struct bio_vec *biovec) | |
1647 | { | |
1648 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 | 1649 | struct dm_table *map = dm_get_live_table_fast(md); |
f6fccb12 MB |
1650 | struct dm_target *ti; |
1651 | sector_t max_sectors; | |
5037108a | 1652 | int max_size = 0; |
f6fccb12 MB |
1653 | |
1654 | if (unlikely(!map)) | |
5037108a | 1655 | goto out; |
f6fccb12 MB |
1656 | |
1657 | ti = dm_table_find_target(map, bvm->bi_sector); | |
b01cd5ac | 1658 | if (!dm_target_is_valid(ti)) |
83d5e5b0 | 1659 | goto out; |
f6fccb12 MB |
1660 | |
1661 | /* | |
1662 | * Find maximum amount of I/O that won't need splitting | |
1663 | */ | |
56a67df7 | 1664 | max_sectors = min(max_io_len(bvm->bi_sector, ti), |
148e51ba | 1665 | (sector_t) queue_max_sectors(q)); |
f6fccb12 | 1666 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; |
148e51ba | 1667 | if (unlikely(max_size < 0)) /* this shouldn't _ever_ happen */ |
f6fccb12 MB |
1668 | max_size = 0; |
1669 | ||
1670 | /* | |
1671 | * merge_bvec_fn() returns number of bytes | |
1672 | * it can accept at this offset | |
1673 | * max is precomputed maximal io size | |
1674 | */ | |
1675 | if (max_size && ti->type->merge) | |
1676 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
8cbeb67a MP |
1677 | /* |
1678 | * If the target doesn't support merge method and some of the devices | |
148e51ba MS |
1679 | * provided their merge_bvec method (we know this by looking for the |
1680 | * max_hw_sectors that dm_set_device_limits may set), then we can't | |
1681 | * allow bios with multiple vector entries. So always set max_size | |
1682 | * to 0, and the code below allows just one page. | |
8cbeb67a MP |
1683 | */ |
1684 | else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9) | |
8cbeb67a | 1685 | max_size = 0; |
f6fccb12 | 1686 | |
5037108a | 1687 | out: |
83d5e5b0 | 1688 | dm_put_live_table_fast(md); |
f6fccb12 MB |
1689 | /* |
1690 | * Always allow an entire first page | |
1691 | */ | |
1692 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
1693 | max_size = biovec->bv_len; | |
1694 | ||
f6fccb12 MB |
1695 | return max_size; |
1696 | } | |
1697 | ||
1da177e4 LT |
1698 | /* |
1699 | * The request function that just remaps the bio built up by | |
1700 | * dm_merge_bvec. | |
1701 | */ | |
ff36ab34 | 1702 | static void dm_make_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 1703 | { |
12f03a49 | 1704 | int rw = bio_data_dir(bio); |
1da177e4 | 1705 | struct mapped_device *md = q->queuedata; |
83d5e5b0 MP |
1706 | int srcu_idx; |
1707 | struct dm_table *map; | |
1da177e4 | 1708 | |
83d5e5b0 | 1709 | map = dm_get_live_table(md, &srcu_idx); |
1da177e4 | 1710 | |
18c0b223 | 1711 | generic_start_io_acct(rw, bio_sectors(bio), &dm_disk(md)->part0); |
12f03a49 | 1712 | |
6a8736d1 TH |
1713 | /* if we're suspended, we have to queue this io for later */ |
1714 | if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { | |
83d5e5b0 | 1715 | dm_put_live_table(md, srcu_idx); |
1da177e4 | 1716 | |
6a8736d1 TH |
1717 | if (bio_rw(bio) != READA) |
1718 | queue_io(md, bio); | |
1719 | else | |
54d9a1b4 | 1720 | bio_io_error(bio); |
5a7bbad2 | 1721 | return; |
1da177e4 LT |
1722 | } |
1723 | ||
83d5e5b0 MP |
1724 | __split_and_process_bio(md, map, bio); |
1725 | dm_put_live_table(md, srcu_idx); | |
5a7bbad2 | 1726 | return; |
cec47e3d KU |
1727 | } |
1728 | ||
fd2ed4d2 | 1729 | int dm_request_based(struct mapped_device *md) |
cec47e3d KU |
1730 | { |
1731 | return blk_queue_stackable(md->queue); | |
1732 | } | |
1733 | ||
466d89a6 | 1734 | static void dm_dispatch_clone_request(struct request *clone, struct request *rq) |
cec47e3d KU |
1735 | { |
1736 | int r; | |
1737 | ||
466d89a6 KB |
1738 | if (blk_queue_io_stat(clone->q)) |
1739 | clone->cmd_flags |= REQ_IO_STAT; | |
cec47e3d | 1740 | |
466d89a6 KB |
1741 | clone->start_time = jiffies; |
1742 | r = blk_insert_cloned_request(clone->q, clone); | |
cec47e3d | 1743 | if (r) |
466d89a6 | 1744 | /* must complete clone in terms of original request */ |
cec47e3d KU |
1745 | dm_complete_request(rq, r); |
1746 | } | |
cec47e3d | 1747 | |
cec47e3d KU |
1748 | static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig, |
1749 | void *data) | |
1750 | { | |
1751 | struct dm_rq_target_io *tio = data; | |
94818742 KO |
1752 | struct dm_rq_clone_bio_info *info = |
1753 | container_of(bio, struct dm_rq_clone_bio_info, clone); | |
cec47e3d KU |
1754 | |
1755 | info->orig = bio_orig; | |
1756 | info->tio = tio; | |
1757 | bio->bi_end_io = end_clone_bio; | |
cec47e3d KU |
1758 | |
1759 | return 0; | |
1760 | } | |
1761 | ||
1762 | static int setup_clone(struct request *clone, struct request *rq, | |
1ae49ea2 | 1763 | struct dm_rq_target_io *tio, gfp_t gfp_mask) |
cec47e3d | 1764 | { |
d0bcb878 | 1765 | int r; |
cec47e3d | 1766 | |
1ae49ea2 | 1767 | r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask, |
29e4013d TH |
1768 | dm_rq_bio_constructor, tio); |
1769 | if (r) | |
1770 | return r; | |
cec47e3d | 1771 | |
29e4013d TH |
1772 | clone->cmd = rq->cmd; |
1773 | clone->cmd_len = rq->cmd_len; | |
1774 | clone->sense = rq->sense; | |
cec47e3d KU |
1775 | clone->end_io = end_clone_request; |
1776 | clone->end_io_data = tio; | |
1777 | ||
1ae49ea2 MS |
1778 | tio->clone = clone; |
1779 | ||
cec47e3d KU |
1780 | return 0; |
1781 | } | |
1782 | ||
6facdaff | 1783 | static struct request *clone_rq(struct request *rq, struct mapped_device *md, |
466d89a6 | 1784 | struct dm_rq_target_io *tio, gfp_t gfp_mask) |
1ae49ea2 MS |
1785 | { |
1786 | struct request *clone = alloc_clone_request(md, gfp_mask); | |
1787 | ||
1788 | if (!clone) | |
1789 | return NULL; | |
1790 | ||
1791 | blk_rq_init(NULL, clone); | |
1792 | if (setup_clone(clone, rq, tio, gfp_mask)) { | |
1793 | /* -ENOMEM */ | |
1794 | free_clone_request(md, clone); | |
1795 | return NULL; | |
1796 | } | |
1797 | ||
1798 | return clone; | |
1799 | } | |
1800 | ||
2eb6e1e3 KB |
1801 | static void map_tio_request(struct kthread_work *work); |
1802 | ||
466d89a6 KB |
1803 | static struct dm_rq_target_io *prep_tio(struct request *rq, |
1804 | struct mapped_device *md, gfp_t gfp_mask) | |
6facdaff | 1805 | { |
6facdaff | 1806 | struct dm_rq_target_io *tio; |
e5863d9a MS |
1807 | int srcu_idx; |
1808 | struct dm_table *table; | |
6facdaff KU |
1809 | |
1810 | tio = alloc_rq_tio(md, gfp_mask); | |
1811 | if (!tio) | |
1812 | return NULL; | |
1813 | ||
1814 | tio->md = md; | |
1815 | tio->ti = NULL; | |
1ae49ea2 | 1816 | tio->clone = NULL; |
6facdaff KU |
1817 | tio->orig = rq; |
1818 | tio->error = 0; | |
1819 | memset(&tio->info, 0, sizeof(tio->info)); | |
2eb6e1e3 | 1820 | init_kthread_work(&tio->work, map_tio_request); |
6facdaff | 1821 | |
e5863d9a MS |
1822 | table = dm_get_live_table(md, &srcu_idx); |
1823 | if (!dm_table_mq_request_based(table)) { | |
1824 | if (!clone_rq(rq, md, tio, gfp_mask)) { | |
1825 | dm_put_live_table(md, srcu_idx); | |
1826 | free_rq_tio(tio); | |
1827 | return NULL; | |
1828 | } | |
6facdaff | 1829 | } |
e5863d9a | 1830 | dm_put_live_table(md, srcu_idx); |
6facdaff | 1831 | |
466d89a6 | 1832 | return tio; |
6facdaff KU |
1833 | } |
1834 | ||
cec47e3d KU |
1835 | /* |
1836 | * Called with the queue lock held. | |
1837 | */ | |
1838 | static int dm_prep_fn(struct request_queue *q, struct request *rq) | |
1839 | { | |
1840 | struct mapped_device *md = q->queuedata; | |
466d89a6 | 1841 | struct dm_rq_target_io *tio; |
cec47e3d | 1842 | |
cec47e3d KU |
1843 | if (unlikely(rq->special)) { |
1844 | DMWARN("Already has something in rq->special."); | |
1845 | return BLKPREP_KILL; | |
1846 | } | |
1847 | ||
466d89a6 KB |
1848 | tio = prep_tio(rq, md, GFP_ATOMIC); |
1849 | if (!tio) | |
cec47e3d | 1850 | return BLKPREP_DEFER; |
cec47e3d | 1851 | |
466d89a6 | 1852 | rq->special = tio; |
cec47e3d KU |
1853 | rq->cmd_flags |= REQ_DONTPREP; |
1854 | ||
1855 | return BLKPREP_OK; | |
1856 | } | |
1857 | ||
9eef87da KU |
1858 | /* |
1859 | * Returns: | |
e5863d9a MS |
1860 | * 0 : the request has been processed |
1861 | * DM_MAPIO_REQUEUE : the original request needs to be requeued | |
1862 | * < 0 : the request was completed due to failure | |
9eef87da | 1863 | */ |
466d89a6 | 1864 | static int map_request(struct dm_target *ti, struct request *rq, |
9eef87da | 1865 | struct mapped_device *md) |
cec47e3d | 1866 | { |
e5863d9a | 1867 | int r; |
466d89a6 | 1868 | struct dm_rq_target_io *tio = rq->special; |
e5863d9a MS |
1869 | struct request *clone = NULL; |
1870 | ||
1871 | if (tio->clone) { | |
1872 | clone = tio->clone; | |
1873 | r = ti->type->map_rq(ti, clone, &tio->info); | |
1874 | } else { | |
1875 | r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone); | |
1876 | if (r < 0) { | |
1877 | /* The target wants to complete the I/O */ | |
1878 | dm_kill_unmapped_request(rq, r); | |
1879 | return r; | |
1880 | } | |
1881 | if (IS_ERR(clone)) | |
1882 | return DM_MAPIO_REQUEUE; | |
1883 | if (setup_clone(clone, rq, tio, GFP_KERNEL)) { | |
1884 | /* -ENOMEM */ | |
1885 | ti->type->release_clone_rq(clone); | |
1886 | return DM_MAPIO_REQUEUE; | |
1887 | } | |
1888 | } | |
cec47e3d | 1889 | |
cec47e3d KU |
1890 | switch (r) { |
1891 | case DM_MAPIO_SUBMITTED: | |
1892 | /* The target has taken the I/O to submit by itself later */ | |
1893 | break; | |
1894 | case DM_MAPIO_REMAPPED: | |
1895 | /* The target has remapped the I/O so dispatch it */ | |
6db4ccd6 | 1896 | trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)), |
466d89a6 KB |
1897 | blk_rq_pos(rq)); |
1898 | dm_dispatch_clone_request(clone, rq); | |
cec47e3d KU |
1899 | break; |
1900 | case DM_MAPIO_REQUEUE: | |
1901 | /* The target wants to requeue the I/O */ | |
1902 | dm_requeue_unmapped_request(clone); | |
1903 | break; | |
1904 | default: | |
1905 | if (r > 0) { | |
1906 | DMWARN("unimplemented target map return value: %d", r); | |
1907 | BUG(); | |
1908 | } | |
1909 | ||
1910 | /* The target wants to complete the I/O */ | |
466d89a6 | 1911 | dm_kill_unmapped_request(rq, r); |
e5863d9a | 1912 | return r; |
cec47e3d | 1913 | } |
9eef87da | 1914 | |
e5863d9a | 1915 | return 0; |
cec47e3d KU |
1916 | } |
1917 | ||
2eb6e1e3 | 1918 | static void map_tio_request(struct kthread_work *work) |
ba1cbad9 | 1919 | { |
2eb6e1e3 | 1920 | struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work); |
e5863d9a MS |
1921 | struct request *rq = tio->orig; |
1922 | struct mapped_device *md = tio->md; | |
ba1cbad9 | 1923 | |
e5863d9a MS |
1924 | if (map_request(tio->ti, rq, md) == DM_MAPIO_REQUEUE) |
1925 | dm_requeue_unmapped_original_request(md, rq); | |
2eb6e1e3 KB |
1926 | } |
1927 | ||
466d89a6 | 1928 | static void dm_start_request(struct mapped_device *md, struct request *orig) |
ba1cbad9 | 1929 | { |
ba1cbad9 | 1930 | blk_start_request(orig); |
466d89a6 | 1931 | atomic_inc(&md->pending[rq_data_dir(orig)]); |
ba1cbad9 MS |
1932 | |
1933 | /* | |
1934 | * Hold the md reference here for the in-flight I/O. | |
1935 | * We can't rely on the reference count by device opener, | |
1936 | * because the device may be closed during the request completion | |
1937 | * when all bios are completed. | |
1938 | * See the comment in rq_completed() too. | |
1939 | */ | |
1940 | dm_get(md); | |
ba1cbad9 MS |
1941 | } |
1942 | ||
cec47e3d KU |
1943 | /* |
1944 | * q->request_fn for request-based dm. | |
1945 | * Called with the queue lock held. | |
1946 | */ | |
1947 | static void dm_request_fn(struct request_queue *q) | |
1948 | { | |
1949 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 MP |
1950 | int srcu_idx; |
1951 | struct dm_table *map = dm_get_live_table(md, &srcu_idx); | |
cec47e3d | 1952 | struct dm_target *ti; |
466d89a6 | 1953 | struct request *rq; |
2eb6e1e3 | 1954 | struct dm_rq_target_io *tio; |
29e4013d | 1955 | sector_t pos; |
cec47e3d KU |
1956 | |
1957 | /* | |
b4324fee KU |
1958 | * For suspend, check blk_queue_stopped() and increment |
1959 | * ->pending within a single queue_lock not to increment the | |
1960 | * number of in-flight I/Os after the queue is stopped in | |
1961 | * dm_suspend(). | |
cec47e3d | 1962 | */ |
7eaceacc | 1963 | while (!blk_queue_stopped(q)) { |
cec47e3d KU |
1964 | rq = blk_peek_request(q); |
1965 | if (!rq) | |
9d1deb83 | 1966 | goto out; |
cec47e3d | 1967 | |
29e4013d TH |
1968 | /* always use block 0 to find the target for flushes for now */ |
1969 | pos = 0; | |
1970 | if (!(rq->cmd_flags & REQ_FLUSH)) | |
1971 | pos = blk_rq_pos(rq); | |
1972 | ||
1973 | ti = dm_table_find_target(map, pos); | |
ba1cbad9 MS |
1974 | if (!dm_target_is_valid(ti)) { |
1975 | /* | |
466d89a6 | 1976 | * Must perform setup, that rq_completed() requires, |
ba1cbad9 MS |
1977 | * before calling dm_kill_unmapped_request |
1978 | */ | |
1979 | DMERR_LIMIT("request attempted access beyond the end of device"); | |
466d89a6 KB |
1980 | dm_start_request(md, rq); |
1981 | dm_kill_unmapped_request(rq, -EIO); | |
ba1cbad9 MS |
1982 | continue; |
1983 | } | |
d0bcb878 | 1984 | |
cec47e3d | 1985 | if (ti->type->busy && ti->type->busy(ti)) |
7eaceacc | 1986 | goto delay_and_out; |
cec47e3d | 1987 | |
466d89a6 | 1988 | dm_start_request(md, rq); |
9eef87da | 1989 | |
2eb6e1e3 KB |
1990 | tio = rq->special; |
1991 | /* Establish tio->ti before queuing work (map_tio_request) */ | |
1992 | tio->ti = ti; | |
1993 | queue_kthread_work(&md->kworker, &tio->work); | |
052189a2 | 1994 | BUG_ON(!irqs_disabled()); |
cec47e3d KU |
1995 | } |
1996 | ||
1997 | goto out; | |
1998 | ||
7eaceacc | 1999 | delay_and_out: |
d548b34b | 2000 | blk_delay_queue(q, HZ / 100); |
cec47e3d | 2001 | out: |
83d5e5b0 | 2002 | dm_put_live_table(md, srcu_idx); |
cec47e3d KU |
2003 | } |
2004 | ||
1da177e4 LT |
2005 | static int dm_any_congested(void *congested_data, int bdi_bits) |
2006 | { | |
8a57dfc6 CS |
2007 | int r = bdi_bits; |
2008 | struct mapped_device *md = congested_data; | |
2009 | struct dm_table *map; | |
1da177e4 | 2010 | |
1eb787ec | 2011 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
83d5e5b0 | 2012 | map = dm_get_live_table_fast(md); |
8a57dfc6 | 2013 | if (map) { |
cec47e3d KU |
2014 | /* |
2015 | * Request-based dm cares about only own queue for | |
2016 | * the query about congestion status of request_queue | |
2017 | */ | |
2018 | if (dm_request_based(md)) | |
2019 | r = md->queue->backing_dev_info.state & | |
2020 | bdi_bits; | |
2021 | else | |
2022 | r = dm_table_any_congested(map, bdi_bits); | |
8a57dfc6 | 2023 | } |
83d5e5b0 | 2024 | dm_put_live_table_fast(md); |
8a57dfc6 CS |
2025 | } |
2026 | ||
1da177e4 LT |
2027 | return r; |
2028 | } | |
2029 | ||
2030 | /*----------------------------------------------------------------- | |
2031 | * An IDR is used to keep track of allocated minor numbers. | |
2032 | *---------------------------------------------------------------*/ | |
2b06cfff | 2033 | static void free_minor(int minor) |
1da177e4 | 2034 | { |
f32c10b0 | 2035 | spin_lock(&_minor_lock); |
1da177e4 | 2036 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 2037 | spin_unlock(&_minor_lock); |
1da177e4 LT |
2038 | } |
2039 | ||
2040 | /* | |
2041 | * See if the device with a specific minor # is free. | |
2042 | */ | |
cf13ab8e | 2043 | static int specific_minor(int minor) |
1da177e4 | 2044 | { |
c9d76be6 | 2045 | int r; |
1da177e4 LT |
2046 | |
2047 | if (minor >= (1 << MINORBITS)) | |
2048 | return -EINVAL; | |
2049 | ||
c9d76be6 | 2050 | idr_preload(GFP_KERNEL); |
f32c10b0 | 2051 | spin_lock(&_minor_lock); |
1da177e4 | 2052 | |
c9d76be6 | 2053 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT); |
1da177e4 | 2054 | |
f32c10b0 | 2055 | spin_unlock(&_minor_lock); |
c9d76be6 TH |
2056 | idr_preload_end(); |
2057 | if (r < 0) | |
2058 | return r == -ENOSPC ? -EBUSY : r; | |
2059 | return 0; | |
1da177e4 LT |
2060 | } |
2061 | ||
cf13ab8e | 2062 | static int next_free_minor(int *minor) |
1da177e4 | 2063 | { |
c9d76be6 | 2064 | int r; |
62f75c2f | 2065 | |
c9d76be6 | 2066 | idr_preload(GFP_KERNEL); |
f32c10b0 | 2067 | spin_lock(&_minor_lock); |
1da177e4 | 2068 | |
c9d76be6 | 2069 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT); |
1da177e4 | 2070 | |
f32c10b0 | 2071 | spin_unlock(&_minor_lock); |
c9d76be6 TH |
2072 | idr_preload_end(); |
2073 | if (r < 0) | |
2074 | return r; | |
2075 | *minor = r; | |
2076 | return 0; | |
1da177e4 LT |
2077 | } |
2078 | ||
83d5cde4 | 2079 | static const struct block_device_operations dm_blk_dops; |
1da177e4 | 2080 | |
53d5914f MP |
2081 | static void dm_wq_work(struct work_struct *work); |
2082 | ||
4a0b4ddf MS |
2083 | static void dm_init_md_queue(struct mapped_device *md) |
2084 | { | |
2085 | /* | |
2086 | * Request-based dm devices cannot be stacked on top of bio-based dm | |
2087 | * devices. The type of this dm device has not been decided yet. | |
2088 | * The type is decided at the first table loading time. | |
2089 | * To prevent problematic device stacking, clear the queue flag | |
2090 | * for request stacking support until then. | |
2091 | * | |
2092 | * This queue is new, so no concurrency on the queue_flags. | |
2093 | */ | |
2094 | queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue); | |
2095 | ||
2096 | md->queue->queuedata = md; | |
2097 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
2098 | md->queue->backing_dev_info.congested_data = md; | |
ff36ab34 | 2099 | |
4a0b4ddf | 2100 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); |
4a0b4ddf MS |
2101 | } |
2102 | ||
1da177e4 LT |
2103 | /* |
2104 | * Allocate and initialise a blank device with a given minor. | |
2105 | */ | |
2b06cfff | 2106 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
2107 | { |
2108 | int r; | |
cf13ab8e | 2109 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 2110 | void *old_md; |
1da177e4 LT |
2111 | |
2112 | if (!md) { | |
2113 | DMWARN("unable to allocate device, out of memory."); | |
2114 | return NULL; | |
2115 | } | |
2116 | ||
10da4f79 | 2117 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 2118 | goto bad_module_get; |
10da4f79 | 2119 | |
1da177e4 | 2120 | /* get a minor number for the dev */ |
2b06cfff | 2121 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 2122 | r = next_free_minor(&minor); |
2b06cfff | 2123 | else |
cf13ab8e | 2124 | r = specific_minor(minor); |
1da177e4 | 2125 | if (r < 0) |
6ed7ade8 | 2126 | goto bad_minor; |
1da177e4 | 2127 | |
83d5e5b0 MP |
2128 | r = init_srcu_struct(&md->io_barrier); |
2129 | if (r < 0) | |
2130 | goto bad_io_barrier; | |
2131 | ||
a5664dad | 2132 | md->type = DM_TYPE_NONE; |
e61290a4 | 2133 | mutex_init(&md->suspend_lock); |
a5664dad | 2134 | mutex_init(&md->type_lock); |
86f1152b | 2135 | mutex_init(&md->table_devices_lock); |
022c2611 | 2136 | spin_lock_init(&md->deferred_lock); |
1da177e4 | 2137 | atomic_set(&md->holders, 1); |
5c6bd75d | 2138 | atomic_set(&md->open_count, 0); |
1da177e4 | 2139 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
2140 | atomic_set(&md->uevent_seq, 0); |
2141 | INIT_LIST_HEAD(&md->uevent_list); | |
86f1152b | 2142 | INIT_LIST_HEAD(&md->table_devices); |
7a8c3d3b | 2143 | spin_lock_init(&md->uevent_lock); |
1da177e4 | 2144 | |
4a0b4ddf | 2145 | md->queue = blk_alloc_queue(GFP_KERNEL); |
1da177e4 | 2146 | if (!md->queue) |
6ed7ade8 | 2147 | goto bad_queue; |
1da177e4 | 2148 | |
4a0b4ddf | 2149 | dm_init_md_queue(md); |
9faf400f | 2150 | |
1da177e4 LT |
2151 | md->disk = alloc_disk(1); |
2152 | if (!md->disk) | |
6ed7ade8 | 2153 | goto bad_disk; |
1da177e4 | 2154 | |
316d315b NK |
2155 | atomic_set(&md->pending[0], 0); |
2156 | atomic_set(&md->pending[1], 0); | |
f0b04115 | 2157 | init_waitqueue_head(&md->wait); |
53d5914f | 2158 | INIT_WORK(&md->work, dm_wq_work); |
f0b04115 | 2159 | init_waitqueue_head(&md->eventq); |
2995fa78 | 2160 | init_completion(&md->kobj_holder.completion); |
2eb6e1e3 | 2161 | md->kworker_task = NULL; |
f0b04115 | 2162 | |
1da177e4 LT |
2163 | md->disk->major = _major; |
2164 | md->disk->first_minor = minor; | |
2165 | md->disk->fops = &dm_blk_dops; | |
2166 | md->disk->queue = md->queue; | |
2167 | md->disk->private_data = md; | |
2168 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
2169 | add_disk(md->disk); | |
7e51f257 | 2170 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 2171 | |
670368a8 | 2172 | md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0); |
304f3f6a MB |
2173 | if (!md->wq) |
2174 | goto bad_thread; | |
2175 | ||
32a926da MP |
2176 | md->bdev = bdget_disk(md->disk, 0); |
2177 | if (!md->bdev) | |
2178 | goto bad_bdev; | |
2179 | ||
6a8736d1 TH |
2180 | bio_init(&md->flush_bio); |
2181 | md->flush_bio.bi_bdev = md->bdev; | |
2182 | md->flush_bio.bi_rw = WRITE_FLUSH; | |
2183 | ||
fd2ed4d2 MP |
2184 | dm_stats_init(&md->stats); |
2185 | ||
ba61fdd1 | 2186 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 2187 | spin_lock(&_minor_lock); |
ba61fdd1 | 2188 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 2189 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
2190 | |
2191 | BUG_ON(old_md != MINOR_ALLOCED); | |
2192 | ||
1da177e4 LT |
2193 | return md; |
2194 | ||
32a926da MP |
2195 | bad_bdev: |
2196 | destroy_workqueue(md->wq); | |
304f3f6a | 2197 | bad_thread: |
03022c54 | 2198 | del_gendisk(md->disk); |
304f3f6a | 2199 | put_disk(md->disk); |
6ed7ade8 | 2200 | bad_disk: |
1312f40e | 2201 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 2202 | bad_queue: |
83d5e5b0 MP |
2203 | cleanup_srcu_struct(&md->io_barrier); |
2204 | bad_io_barrier: | |
1da177e4 | 2205 | free_minor(minor); |
6ed7ade8 | 2206 | bad_minor: |
10da4f79 | 2207 | module_put(THIS_MODULE); |
6ed7ade8 | 2208 | bad_module_get: |
1da177e4 LT |
2209 | kfree(md); |
2210 | return NULL; | |
2211 | } | |
2212 | ||
ae9da83f JN |
2213 | static void unlock_fs(struct mapped_device *md); |
2214 | ||
1da177e4 LT |
2215 | static void free_dev(struct mapped_device *md) |
2216 | { | |
f331c029 | 2217 | int minor = MINOR(disk_devt(md->disk)); |
63d94e48 | 2218 | |
32a926da | 2219 | unlock_fs(md); |
304f3f6a | 2220 | destroy_workqueue(md->wq); |
2eb6e1e3 KB |
2221 | |
2222 | if (md->kworker_task) | |
2223 | kthread_stop(md->kworker_task); | |
e6ee8c0b KU |
2224 | if (md->io_pool) |
2225 | mempool_destroy(md->io_pool); | |
1ae49ea2 MS |
2226 | if (md->rq_pool) |
2227 | mempool_destroy(md->rq_pool); | |
e6ee8c0b KU |
2228 | if (md->bs) |
2229 | bioset_free(md->bs); | |
63a4f065 | 2230 | |
83d5e5b0 | 2231 | cleanup_srcu_struct(&md->io_barrier); |
86f1152b | 2232 | free_table_devices(&md->table_devices); |
63a4f065 | 2233 | dm_stats_cleanup(&md->stats); |
fba9f90e JM |
2234 | |
2235 | spin_lock(&_minor_lock); | |
2236 | md->disk->private_data = NULL; | |
2237 | spin_unlock(&_minor_lock); | |
63a4f065 MS |
2238 | if (blk_get_integrity(md->disk)) |
2239 | blk_integrity_unregister(md->disk); | |
2240 | del_gendisk(md->disk); | |
1da177e4 | 2241 | put_disk(md->disk); |
1312f40e | 2242 | blk_cleanup_queue(md->queue); |
63a4f065 MS |
2243 | bdput(md->bdev); |
2244 | free_minor(minor); | |
2245 | ||
10da4f79 | 2246 | module_put(THIS_MODULE); |
1da177e4 LT |
2247 | kfree(md); |
2248 | } | |
2249 | ||
e6ee8c0b KU |
2250 | static void __bind_mempools(struct mapped_device *md, struct dm_table *t) |
2251 | { | |
c0820cf5 | 2252 | struct dm_md_mempools *p = dm_table_get_md_mempools(t); |
e6ee8c0b | 2253 | |
5f015204 | 2254 | if (md->io_pool && md->bs) { |
16245bdc JN |
2255 | /* The md already has necessary mempools. */ |
2256 | if (dm_table_get_type(t) == DM_TYPE_BIO_BASED) { | |
2257 | /* | |
2258 | * Reload bioset because front_pad may have changed | |
2259 | * because a different table was loaded. | |
2260 | */ | |
2261 | bioset_free(md->bs); | |
2262 | md->bs = p->bs; | |
2263 | p->bs = NULL; | |
16245bdc | 2264 | } |
466d89a6 KB |
2265 | /* |
2266 | * There's no need to reload with request-based dm | |
2267 | * because the size of front_pad doesn't change. | |
2268 | * Note for future: If you are to reload bioset, | |
2269 | * prep-ed requests in the queue may refer | |
2270 | * to bio from the old bioset, so you must walk | |
2271 | * through the queue to unprep. | |
2272 | */ | |
e6ee8c0b | 2273 | goto out; |
c0820cf5 | 2274 | } |
e6ee8c0b | 2275 | |
1ae49ea2 | 2276 | BUG_ON(!p || md->io_pool || md->rq_pool || md->bs); |
e6ee8c0b KU |
2277 | |
2278 | md->io_pool = p->io_pool; | |
2279 | p->io_pool = NULL; | |
1ae49ea2 MS |
2280 | md->rq_pool = p->rq_pool; |
2281 | p->rq_pool = NULL; | |
e6ee8c0b KU |
2282 | md->bs = p->bs; |
2283 | p->bs = NULL; | |
2284 | ||
2285 | out: | |
2286 | /* mempool bind completed, now no need any mempools in the table */ | |
2287 | dm_table_free_md_mempools(t); | |
2288 | } | |
2289 | ||
1da177e4 LT |
2290 | /* |
2291 | * Bind a table to the device. | |
2292 | */ | |
2293 | static void event_callback(void *context) | |
2294 | { | |
7a8c3d3b MA |
2295 | unsigned long flags; |
2296 | LIST_HEAD(uevents); | |
1da177e4 LT |
2297 | struct mapped_device *md = (struct mapped_device *) context; |
2298 | ||
7a8c3d3b MA |
2299 | spin_lock_irqsave(&md->uevent_lock, flags); |
2300 | list_splice_init(&md->uevent_list, &uevents); | |
2301 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2302 | ||
ed9e1982 | 2303 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
7a8c3d3b | 2304 | |
1da177e4 LT |
2305 | atomic_inc(&md->event_nr); |
2306 | wake_up(&md->eventq); | |
2307 | } | |
2308 | ||
c217649b MS |
2309 | /* |
2310 | * Protected by md->suspend_lock obtained by dm_swap_table(). | |
2311 | */ | |
4e90188b | 2312 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 2313 | { |
4e90188b | 2314 | set_capacity(md->disk, size); |
1da177e4 | 2315 | |
db8fef4f | 2316 | i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
1da177e4 LT |
2317 | } |
2318 | ||
d5b9dd04 MP |
2319 | /* |
2320 | * Return 1 if the queue has a compulsory merge_bvec_fn function. | |
2321 | * | |
2322 | * If this function returns 0, then the device is either a non-dm | |
2323 | * device without a merge_bvec_fn, or it is a dm device that is | |
2324 | * able to split any bios it receives that are too big. | |
2325 | */ | |
2326 | int dm_queue_merge_is_compulsory(struct request_queue *q) | |
2327 | { | |
2328 | struct mapped_device *dev_md; | |
2329 | ||
2330 | if (!q->merge_bvec_fn) | |
2331 | return 0; | |
2332 | ||
ff36ab34 | 2333 | if (q->make_request_fn == dm_make_request) { |
d5b9dd04 MP |
2334 | dev_md = q->queuedata; |
2335 | if (test_bit(DMF_MERGE_IS_OPTIONAL, &dev_md->flags)) | |
2336 | return 0; | |
2337 | } | |
2338 | ||
2339 | return 1; | |
2340 | } | |
2341 | ||
2342 | static int dm_device_merge_is_compulsory(struct dm_target *ti, | |
2343 | struct dm_dev *dev, sector_t start, | |
2344 | sector_t len, void *data) | |
2345 | { | |
2346 | struct block_device *bdev = dev->bdev; | |
2347 | struct request_queue *q = bdev_get_queue(bdev); | |
2348 | ||
2349 | return dm_queue_merge_is_compulsory(q); | |
2350 | } | |
2351 | ||
2352 | /* | |
2353 | * Return 1 if it is acceptable to ignore merge_bvec_fn based | |
2354 | * on the properties of the underlying devices. | |
2355 | */ | |
2356 | static int dm_table_merge_is_optional(struct dm_table *table) | |
2357 | { | |
2358 | unsigned i = 0; | |
2359 | struct dm_target *ti; | |
2360 | ||
2361 | while (i < dm_table_get_num_targets(table)) { | |
2362 | ti = dm_table_get_target(table, i++); | |
2363 | ||
2364 | if (ti->type->iterate_devices && | |
2365 | ti->type->iterate_devices(ti, dm_device_merge_is_compulsory, NULL)) | |
2366 | return 0; | |
2367 | } | |
2368 | ||
2369 | return 1; | |
2370 | } | |
2371 | ||
042d2a9b AK |
2372 | /* |
2373 | * Returns old map, which caller must destroy. | |
2374 | */ | |
2375 | static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, | |
2376 | struct queue_limits *limits) | |
1da177e4 | 2377 | { |
042d2a9b | 2378 | struct dm_table *old_map; |
165125e1 | 2379 | struct request_queue *q = md->queue; |
1da177e4 | 2380 | sector_t size; |
d5b9dd04 | 2381 | int merge_is_optional; |
1da177e4 LT |
2382 | |
2383 | size = dm_table_get_size(t); | |
3ac51e74 DW |
2384 | |
2385 | /* | |
2386 | * Wipe any geometry if the size of the table changed. | |
2387 | */ | |
fd2ed4d2 | 2388 | if (size != dm_get_size(md)) |
3ac51e74 DW |
2389 | memset(&md->geometry, 0, sizeof(md->geometry)); |
2390 | ||
32a926da | 2391 | __set_size(md, size); |
d5816876 | 2392 | |
2ca3310e AK |
2393 | dm_table_event_callback(t, event_callback, md); |
2394 | ||
e6ee8c0b KU |
2395 | /* |
2396 | * The queue hasn't been stopped yet, if the old table type wasn't | |
2397 | * for request-based during suspension. So stop it to prevent | |
2398 | * I/O mapping before resume. | |
2399 | * This must be done before setting the queue restrictions, | |
2400 | * because request-based dm may be run just after the setting. | |
2401 | */ | |
2402 | if (dm_table_request_based(t) && !blk_queue_stopped(q)) | |
2403 | stop_queue(q); | |
2404 | ||
2405 | __bind_mempools(md, t); | |
2406 | ||
d5b9dd04 MP |
2407 | merge_is_optional = dm_table_merge_is_optional(t); |
2408 | ||
a12f5d48 | 2409 | old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
83d5e5b0 | 2410 | rcu_assign_pointer(md->map, t); |
36a0456f AK |
2411 | md->immutable_target_type = dm_table_get_immutable_target_type(t); |
2412 | ||
754c5fc7 | 2413 | dm_table_set_restrictions(t, q, limits); |
d5b9dd04 MP |
2414 | if (merge_is_optional) |
2415 | set_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
2416 | else | |
2417 | clear_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
41abc4e1 HR |
2418 | if (old_map) |
2419 | dm_sync_table(md); | |
1da177e4 | 2420 | |
042d2a9b | 2421 | return old_map; |
1da177e4 LT |
2422 | } |
2423 | ||
a7940155 AK |
2424 | /* |
2425 | * Returns unbound table for the caller to free. | |
2426 | */ | |
2427 | static struct dm_table *__unbind(struct mapped_device *md) | |
1da177e4 | 2428 | { |
a12f5d48 | 2429 | struct dm_table *map = rcu_dereference_protected(md->map, 1); |
1da177e4 LT |
2430 | |
2431 | if (!map) | |
a7940155 | 2432 | return NULL; |
1da177e4 LT |
2433 | |
2434 | dm_table_event_callback(map, NULL, NULL); | |
9cdb8520 | 2435 | RCU_INIT_POINTER(md->map, NULL); |
83d5e5b0 | 2436 | dm_sync_table(md); |
a7940155 AK |
2437 | |
2438 | return map; | |
1da177e4 LT |
2439 | } |
2440 | ||
2441 | /* | |
2442 | * Constructor for a new device. | |
2443 | */ | |
2b06cfff | 2444 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
2445 | { |
2446 | struct mapped_device *md; | |
2447 | ||
2b06cfff | 2448 | md = alloc_dev(minor); |
1da177e4 LT |
2449 | if (!md) |
2450 | return -ENXIO; | |
2451 | ||
784aae73 MB |
2452 | dm_sysfs_init(md); |
2453 | ||
1da177e4 LT |
2454 | *result = md; |
2455 | return 0; | |
2456 | } | |
2457 | ||
a5664dad MS |
2458 | /* |
2459 | * Functions to manage md->type. | |
2460 | * All are required to hold md->type_lock. | |
2461 | */ | |
2462 | void dm_lock_md_type(struct mapped_device *md) | |
2463 | { | |
2464 | mutex_lock(&md->type_lock); | |
2465 | } | |
2466 | ||
2467 | void dm_unlock_md_type(struct mapped_device *md) | |
2468 | { | |
2469 | mutex_unlock(&md->type_lock); | |
2470 | } | |
2471 | ||
2472 | void dm_set_md_type(struct mapped_device *md, unsigned type) | |
2473 | { | |
00c4fc3b | 2474 | BUG_ON(!mutex_is_locked(&md->type_lock)); |
a5664dad MS |
2475 | md->type = type; |
2476 | } | |
2477 | ||
2478 | unsigned dm_get_md_type(struct mapped_device *md) | |
2479 | { | |
00c4fc3b | 2480 | BUG_ON(!mutex_is_locked(&md->type_lock)); |
a5664dad MS |
2481 | return md->type; |
2482 | } | |
2483 | ||
e5863d9a MS |
2484 | static bool dm_md_type_request_based(struct mapped_device *md) |
2485 | { | |
2486 | unsigned table_type = dm_get_md_type(md); | |
2487 | ||
2488 | return (table_type == DM_TYPE_REQUEST_BASED || | |
2489 | table_type == DM_TYPE_MQ_REQUEST_BASED); | |
2490 | } | |
2491 | ||
36a0456f AK |
2492 | struct target_type *dm_get_immutable_target_type(struct mapped_device *md) |
2493 | { | |
2494 | return md->immutable_target_type; | |
2495 | } | |
2496 | ||
f84cb8a4 MS |
2497 | /* |
2498 | * The queue_limits are only valid as long as you have a reference | |
2499 | * count on 'md'. | |
2500 | */ | |
2501 | struct queue_limits *dm_get_queue_limits(struct mapped_device *md) | |
2502 | { | |
2503 | BUG_ON(!atomic_read(&md->holders)); | |
2504 | return &md->queue->limits; | |
2505 | } | |
2506 | EXPORT_SYMBOL_GPL(dm_get_queue_limits); | |
2507 | ||
4a0b4ddf MS |
2508 | /* |
2509 | * Fully initialize a request-based queue (->elevator, ->request_fn, etc). | |
2510 | */ | |
2511 | static int dm_init_request_based_queue(struct mapped_device *md) | |
2512 | { | |
2513 | struct request_queue *q = NULL; | |
2514 | ||
2515 | if (md->queue->elevator) | |
2516 | return 1; | |
2517 | ||
2518 | /* Fully initialize the queue */ | |
2519 | q = blk_init_allocated_queue(md->queue, dm_request_fn, NULL); | |
2520 | if (!q) | |
2521 | return 0; | |
2522 | ||
2523 | md->queue = q; | |
4a0b4ddf MS |
2524 | dm_init_md_queue(md); |
2525 | blk_queue_softirq_done(md->queue, dm_softirq_done); | |
2526 | blk_queue_prep_rq(md->queue, dm_prep_fn); | |
4a0b4ddf | 2527 | |
2eb6e1e3 KB |
2528 | /* Also initialize the request-based DM worker thread */ |
2529 | init_kthread_worker(&md->kworker); | |
2530 | md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker, | |
2531 | "kdmwork-%s", dm_device_name(md)); | |
2532 | ||
4a0b4ddf MS |
2533 | elv_register_queue(md->queue); |
2534 | ||
2535 | return 1; | |
2536 | } | |
2537 | ||
2538 | /* | |
2539 | * Setup the DM device's queue based on md's type | |
2540 | */ | |
2541 | int dm_setup_md_queue(struct mapped_device *md) | |
2542 | { | |
ff36ab34 MS |
2543 | if (dm_md_type_request_based(md)) { |
2544 | if (!dm_init_request_based_queue(md)) { | |
2545 | DMWARN("Cannot initialize queue for request-based mapped device"); | |
2546 | return -EINVAL; | |
2547 | } | |
2548 | } else { | |
2549 | /* bio-based specific initialization */ | |
2550 | blk_queue_make_request(md->queue, dm_make_request); | |
2551 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); | |
4a0b4ddf MS |
2552 | } |
2553 | ||
2554 | return 0; | |
2555 | } | |
2556 | ||
2bec1f4a | 2557 | struct mapped_device *dm_get_md(dev_t dev) |
1da177e4 LT |
2558 | { |
2559 | struct mapped_device *md; | |
1da177e4 LT |
2560 | unsigned minor = MINOR(dev); |
2561 | ||
2562 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
2563 | return NULL; | |
2564 | ||
f32c10b0 | 2565 | spin_lock(&_minor_lock); |
1da177e4 LT |
2566 | |
2567 | md = idr_find(&_minor_idr, minor); | |
2bec1f4a MP |
2568 | if (md) { |
2569 | if ((md == MINOR_ALLOCED || | |
2570 | (MINOR(disk_devt(dm_disk(md))) != minor) || | |
2571 | dm_deleting_md(md) || | |
2572 | test_bit(DMF_FREEING, &md->flags))) { | |
2573 | md = NULL; | |
2574 | goto out; | |
2575 | } | |
2576 | dm_get(md); | |
fba9f90e | 2577 | } |
1da177e4 | 2578 | |
fba9f90e | 2579 | out: |
f32c10b0 | 2580 | spin_unlock(&_minor_lock); |
1da177e4 | 2581 | |
637842cf DT |
2582 | return md; |
2583 | } | |
3cf2e4ba | 2584 | EXPORT_SYMBOL_GPL(dm_get_md); |
d229a958 | 2585 | |
9ade92a9 | 2586 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 2587 | { |
9ade92a9 | 2588 | return md->interface_ptr; |
1da177e4 LT |
2589 | } |
2590 | ||
2591 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
2592 | { | |
2593 | md->interface_ptr = ptr; | |
2594 | } | |
2595 | ||
2596 | void dm_get(struct mapped_device *md) | |
2597 | { | |
2598 | atomic_inc(&md->holders); | |
3f77316d | 2599 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
1da177e4 LT |
2600 | } |
2601 | ||
09ee96b2 MP |
2602 | int dm_hold(struct mapped_device *md) |
2603 | { | |
2604 | spin_lock(&_minor_lock); | |
2605 | if (test_bit(DMF_FREEING, &md->flags)) { | |
2606 | spin_unlock(&_minor_lock); | |
2607 | return -EBUSY; | |
2608 | } | |
2609 | dm_get(md); | |
2610 | spin_unlock(&_minor_lock); | |
2611 | return 0; | |
2612 | } | |
2613 | EXPORT_SYMBOL_GPL(dm_hold); | |
2614 | ||
72d94861 AK |
2615 | const char *dm_device_name(struct mapped_device *md) |
2616 | { | |
2617 | return md->name; | |
2618 | } | |
2619 | EXPORT_SYMBOL_GPL(dm_device_name); | |
2620 | ||
3f77316d | 2621 | static void __dm_destroy(struct mapped_device *md, bool wait) |
1da177e4 | 2622 | { |
1134e5ae | 2623 | struct dm_table *map; |
83d5e5b0 | 2624 | int srcu_idx; |
1da177e4 | 2625 | |
3f77316d | 2626 | might_sleep(); |
fba9f90e | 2627 | |
83d5e5b0 | 2628 | map = dm_get_live_table(md, &srcu_idx); |
63a4f065 MS |
2629 | |
2630 | spin_lock(&_minor_lock); | |
3f77316d KU |
2631 | idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); |
2632 | set_bit(DMF_FREEING, &md->flags); | |
2633 | spin_unlock(&_minor_lock); | |
2634 | ||
2eb6e1e3 KB |
2635 | if (dm_request_based(md)) |
2636 | flush_kthread_worker(&md->kworker); | |
2637 | ||
ab7c7bb6 MP |
2638 | /* |
2639 | * Take suspend_lock so that presuspend and postsuspend methods | |
2640 | * do not race with internal suspend. | |
2641 | */ | |
2642 | mutex_lock(&md->suspend_lock); | |
3f77316d KU |
2643 | if (!dm_suspended_md(md)) { |
2644 | dm_table_presuspend_targets(map); | |
2645 | dm_table_postsuspend_targets(map); | |
1da177e4 | 2646 | } |
ab7c7bb6 | 2647 | mutex_unlock(&md->suspend_lock); |
3f77316d | 2648 | |
83d5e5b0 MP |
2649 | /* dm_put_live_table must be before msleep, otherwise deadlock is possible */ |
2650 | dm_put_live_table(md, srcu_idx); | |
2651 | ||
3f77316d KU |
2652 | /* |
2653 | * Rare, but there may be I/O requests still going to complete, | |
2654 | * for example. Wait for all references to disappear. | |
2655 | * No one should increment the reference count of the mapped_device, | |
2656 | * after the mapped_device state becomes DMF_FREEING. | |
2657 | */ | |
2658 | if (wait) | |
2659 | while (atomic_read(&md->holders)) | |
2660 | msleep(1); | |
2661 | else if (atomic_read(&md->holders)) | |
2662 | DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", | |
2663 | dm_device_name(md), atomic_read(&md->holders)); | |
2664 | ||
2665 | dm_sysfs_exit(md); | |
3f77316d KU |
2666 | dm_table_destroy(__unbind(md)); |
2667 | free_dev(md); | |
2668 | } | |
2669 | ||
2670 | void dm_destroy(struct mapped_device *md) | |
2671 | { | |
2672 | __dm_destroy(md, true); | |
2673 | } | |
2674 | ||
2675 | void dm_destroy_immediate(struct mapped_device *md) | |
2676 | { | |
2677 | __dm_destroy(md, false); | |
2678 | } | |
2679 | ||
2680 | void dm_put(struct mapped_device *md) | |
2681 | { | |
2682 | atomic_dec(&md->holders); | |
1da177e4 | 2683 | } |
79eb885c | 2684 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 2685 | |
401600df | 2686 | static int dm_wait_for_completion(struct mapped_device *md, int interruptible) |
46125c1c MB |
2687 | { |
2688 | int r = 0; | |
b44ebeb0 MP |
2689 | DECLARE_WAITQUEUE(wait, current); |
2690 | ||
b44ebeb0 | 2691 | add_wait_queue(&md->wait, &wait); |
46125c1c MB |
2692 | |
2693 | while (1) { | |
401600df | 2694 | set_current_state(interruptible); |
46125c1c | 2695 | |
b4324fee | 2696 | if (!md_in_flight(md)) |
46125c1c MB |
2697 | break; |
2698 | ||
401600df MP |
2699 | if (interruptible == TASK_INTERRUPTIBLE && |
2700 | signal_pending(current)) { | |
46125c1c MB |
2701 | r = -EINTR; |
2702 | break; | |
2703 | } | |
2704 | ||
2705 | io_schedule(); | |
2706 | } | |
2707 | set_current_state(TASK_RUNNING); | |
2708 | ||
b44ebeb0 MP |
2709 | remove_wait_queue(&md->wait, &wait); |
2710 | ||
46125c1c MB |
2711 | return r; |
2712 | } | |
2713 | ||
1da177e4 LT |
2714 | /* |
2715 | * Process the deferred bios | |
2716 | */ | |
ef208587 | 2717 | static void dm_wq_work(struct work_struct *work) |
1da177e4 | 2718 | { |
ef208587 MP |
2719 | struct mapped_device *md = container_of(work, struct mapped_device, |
2720 | work); | |
6d6f10df | 2721 | struct bio *c; |
83d5e5b0 MP |
2722 | int srcu_idx; |
2723 | struct dm_table *map; | |
1da177e4 | 2724 | |
83d5e5b0 | 2725 | map = dm_get_live_table(md, &srcu_idx); |
ef208587 | 2726 | |
3b00b203 | 2727 | while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
df12ee99 AK |
2728 | spin_lock_irq(&md->deferred_lock); |
2729 | c = bio_list_pop(&md->deferred); | |
2730 | spin_unlock_irq(&md->deferred_lock); | |
2731 | ||
6a8736d1 | 2732 | if (!c) |
df12ee99 | 2733 | break; |
022c2611 | 2734 | |
e6ee8c0b KU |
2735 | if (dm_request_based(md)) |
2736 | generic_make_request(c); | |
6a8736d1 | 2737 | else |
83d5e5b0 | 2738 | __split_and_process_bio(md, map, c); |
022c2611 | 2739 | } |
73d410c0 | 2740 | |
83d5e5b0 | 2741 | dm_put_live_table(md, srcu_idx); |
1da177e4 LT |
2742 | } |
2743 | ||
9a1fb464 | 2744 | static void dm_queue_flush(struct mapped_device *md) |
304f3f6a | 2745 | { |
3b00b203 | 2746 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
4e857c58 | 2747 | smp_mb__after_atomic(); |
53d5914f | 2748 | queue_work(md->wq, &md->work); |
304f3f6a MB |
2749 | } |
2750 | ||
1da177e4 | 2751 | /* |
042d2a9b | 2752 | * Swap in a new table, returning the old one for the caller to destroy. |
1da177e4 | 2753 | */ |
042d2a9b | 2754 | struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) |
1da177e4 | 2755 | { |
87eb5b21 | 2756 | struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL); |
754c5fc7 | 2757 | struct queue_limits limits; |
042d2a9b | 2758 | int r; |
1da177e4 | 2759 | |
e61290a4 | 2760 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
2761 | |
2762 | /* device must be suspended */ | |
4f186f8b | 2763 | if (!dm_suspended_md(md)) |
93c534ae | 2764 | goto out; |
1da177e4 | 2765 | |
3ae70656 MS |
2766 | /* |
2767 | * If the new table has no data devices, retain the existing limits. | |
2768 | * This helps multipath with queue_if_no_path if all paths disappear, | |
2769 | * then new I/O is queued based on these limits, and then some paths | |
2770 | * reappear. | |
2771 | */ | |
2772 | if (dm_table_has_no_data_devices(table)) { | |
83d5e5b0 | 2773 | live_map = dm_get_live_table_fast(md); |
3ae70656 MS |
2774 | if (live_map) |
2775 | limits = md->queue->limits; | |
83d5e5b0 | 2776 | dm_put_live_table_fast(md); |
3ae70656 MS |
2777 | } |
2778 | ||
87eb5b21 MC |
2779 | if (!live_map) { |
2780 | r = dm_calculate_queue_limits(table, &limits); | |
2781 | if (r) { | |
2782 | map = ERR_PTR(r); | |
2783 | goto out; | |
2784 | } | |
042d2a9b | 2785 | } |
754c5fc7 | 2786 | |
042d2a9b | 2787 | map = __bind(md, table, &limits); |
1da177e4 | 2788 | |
93c534ae | 2789 | out: |
e61290a4 | 2790 | mutex_unlock(&md->suspend_lock); |
042d2a9b | 2791 | return map; |
1da177e4 LT |
2792 | } |
2793 | ||
2794 | /* | |
2795 | * Functions to lock and unlock any filesystem running on the | |
2796 | * device. | |
2797 | */ | |
2ca3310e | 2798 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 2799 | { |
e39e2e95 | 2800 | int r; |
1da177e4 LT |
2801 | |
2802 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 2803 | |
db8fef4f | 2804 | md->frozen_sb = freeze_bdev(md->bdev); |
dfbe03f6 | 2805 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 2806 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
2807 | md->frozen_sb = NULL; |
2808 | return r; | |
dfbe03f6 AK |
2809 | } |
2810 | ||
aa8d7c2f AK |
2811 | set_bit(DMF_FROZEN, &md->flags); |
2812 | ||
1da177e4 LT |
2813 | return 0; |
2814 | } | |
2815 | ||
2ca3310e | 2816 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 2817 | { |
aa8d7c2f AK |
2818 | if (!test_bit(DMF_FROZEN, &md->flags)) |
2819 | return; | |
2820 | ||
db8fef4f | 2821 | thaw_bdev(md->bdev, md->frozen_sb); |
1da177e4 | 2822 | md->frozen_sb = NULL; |
aa8d7c2f | 2823 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
2824 | } |
2825 | ||
2826 | /* | |
ffcc3936 MS |
2827 | * If __dm_suspend returns 0, the device is completely quiescent |
2828 | * now. There is no request-processing activity. All new requests | |
2829 | * are being added to md->deferred list. | |
cec47e3d | 2830 | * |
ffcc3936 | 2831 | * Caller must hold md->suspend_lock |
cec47e3d | 2832 | */ |
ffcc3936 MS |
2833 | static int __dm_suspend(struct mapped_device *md, struct dm_table *map, |
2834 | unsigned suspend_flags, int interruptible) | |
1da177e4 | 2835 | { |
ffcc3936 MS |
2836 | bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG; |
2837 | bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG; | |
2838 | int r; | |
1da177e4 | 2839 | |
2e93ccc1 KU |
2840 | /* |
2841 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
2842 | * This flag is cleared before dm_suspend returns. | |
2843 | */ | |
2844 | if (noflush) | |
2845 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
2846 | ||
d67ee213 MS |
2847 | /* |
2848 | * This gets reverted if there's an error later and the targets | |
2849 | * provide the .presuspend_undo hook. | |
2850 | */ | |
cf222b37 AK |
2851 | dm_table_presuspend_targets(map); |
2852 | ||
32a926da | 2853 | /* |
9f518b27 KU |
2854 | * Flush I/O to the device. |
2855 | * Any I/O submitted after lock_fs() may not be flushed. | |
2856 | * noflush takes precedence over do_lockfs. | |
2857 | * (lock_fs() flushes I/Os and waits for them to complete.) | |
32a926da MP |
2858 | */ |
2859 | if (!noflush && do_lockfs) { | |
2860 | r = lock_fs(md); | |
d67ee213 MS |
2861 | if (r) { |
2862 | dm_table_presuspend_undo_targets(map); | |
ffcc3936 | 2863 | return r; |
d67ee213 | 2864 | } |
aa8d7c2f | 2865 | } |
1da177e4 LT |
2866 | |
2867 | /* | |
3b00b203 MP |
2868 | * Here we must make sure that no processes are submitting requests |
2869 | * to target drivers i.e. no one may be executing | |
2870 | * __split_and_process_bio. This is called from dm_request and | |
2871 | * dm_wq_work. | |
2872 | * | |
2873 | * To get all processes out of __split_and_process_bio in dm_request, | |
2874 | * we take the write lock. To prevent any process from reentering | |
6a8736d1 TH |
2875 | * __split_and_process_bio from dm_request and quiesce the thread |
2876 | * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call | |
2877 | * flush_workqueue(md->wq). | |
1da177e4 | 2878 | */ |
1eb787ec | 2879 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
41abc4e1 HR |
2880 | if (map) |
2881 | synchronize_srcu(&md->io_barrier); | |
1da177e4 | 2882 | |
d0bcb878 | 2883 | /* |
29e4013d TH |
2884 | * Stop md->queue before flushing md->wq in case request-based |
2885 | * dm defers requests to md->wq from md->queue. | |
d0bcb878 | 2886 | */ |
2eb6e1e3 | 2887 | if (dm_request_based(md)) { |
9f518b27 | 2888 | stop_queue(md->queue); |
2eb6e1e3 KB |
2889 | flush_kthread_worker(&md->kworker); |
2890 | } | |
cec47e3d | 2891 | |
d0bcb878 KU |
2892 | flush_workqueue(md->wq); |
2893 | ||
1da177e4 | 2894 | /* |
3b00b203 MP |
2895 | * At this point no more requests are entering target request routines. |
2896 | * We call dm_wait_for_completion to wait for all existing requests | |
2897 | * to finish. | |
1da177e4 | 2898 | */ |
ffcc3936 | 2899 | r = dm_wait_for_completion(md, interruptible); |
1da177e4 | 2900 | |
6d6f10df | 2901 | if (noflush) |
022c2611 | 2902 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
41abc4e1 HR |
2903 | if (map) |
2904 | synchronize_srcu(&md->io_barrier); | |
2e93ccc1 | 2905 | |
1da177e4 | 2906 | /* were we interrupted ? */ |
46125c1c | 2907 | if (r < 0) { |
9a1fb464 | 2908 | dm_queue_flush(md); |
73d410c0 | 2909 | |
cec47e3d | 2910 | if (dm_request_based(md)) |
9f518b27 | 2911 | start_queue(md->queue); |
cec47e3d | 2912 | |
2ca3310e | 2913 | unlock_fs(md); |
d67ee213 | 2914 | dm_table_presuspend_undo_targets(map); |
ffcc3936 | 2915 | /* pushback list is already flushed, so skip flush */ |
2ca3310e | 2916 | } |
1da177e4 | 2917 | |
ffcc3936 MS |
2918 | return r; |
2919 | } | |
2920 | ||
2921 | /* | |
2922 | * We need to be able to change a mapping table under a mounted | |
2923 | * filesystem. For example we might want to move some data in | |
2924 | * the background. Before the table can be swapped with | |
2925 | * dm_bind_table, dm_suspend must be called to flush any in | |
2926 | * flight bios and ensure that any further io gets deferred. | |
2927 | */ | |
2928 | /* | |
2929 | * Suspend mechanism in request-based dm. | |
2930 | * | |
2931 | * 1. Flush all I/Os by lock_fs() if needed. | |
2932 | * 2. Stop dispatching any I/O by stopping the request_queue. | |
2933 | * 3. Wait for all in-flight I/Os to be completed or requeued. | |
2934 | * | |
2935 | * To abort suspend, start the request_queue. | |
2936 | */ | |
2937 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) | |
2938 | { | |
2939 | struct dm_table *map = NULL; | |
2940 | int r = 0; | |
2941 | ||
2942 | retry: | |
2943 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
2944 | ||
2945 | if (dm_suspended_md(md)) { | |
2946 | r = -EINVAL; | |
2947 | goto out_unlock; | |
2948 | } | |
2949 | ||
2950 | if (dm_suspended_internally_md(md)) { | |
2951 | /* already internally suspended, wait for internal resume */ | |
2952 | mutex_unlock(&md->suspend_lock); | |
2953 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
2954 | if (r) | |
2955 | return r; | |
2956 | goto retry; | |
2957 | } | |
2958 | ||
a12f5d48 | 2959 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
ffcc3936 MS |
2960 | |
2961 | r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE); | |
2962 | if (r) | |
2963 | goto out_unlock; | |
3b00b203 | 2964 | |
2ca3310e | 2965 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 2966 | |
4d4471cb KU |
2967 | dm_table_postsuspend_targets(map); |
2968 | ||
d287483d | 2969 | out_unlock: |
e61290a4 | 2970 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 2971 | return r; |
1da177e4 LT |
2972 | } |
2973 | ||
ffcc3936 MS |
2974 | static int __dm_resume(struct mapped_device *md, struct dm_table *map) |
2975 | { | |
2976 | if (map) { | |
2977 | int r = dm_table_resume_targets(map); | |
2978 | if (r) | |
2979 | return r; | |
2980 | } | |
2981 | ||
2982 | dm_queue_flush(md); | |
2983 | ||
2984 | /* | |
2985 | * Flushing deferred I/Os must be done after targets are resumed | |
2986 | * so that mapping of targets can work correctly. | |
2987 | * Request-based dm is queueing the deferred I/Os in its request_queue. | |
2988 | */ | |
2989 | if (dm_request_based(md)) | |
2990 | start_queue(md->queue); | |
2991 | ||
2992 | unlock_fs(md); | |
2993 | ||
2994 | return 0; | |
2995 | } | |
2996 | ||
1da177e4 LT |
2997 | int dm_resume(struct mapped_device *md) |
2998 | { | |
cf222b37 | 2999 | int r = -EINVAL; |
cf222b37 | 3000 | struct dm_table *map = NULL; |
1da177e4 | 3001 | |
ffcc3936 MS |
3002 | retry: |
3003 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
3004 | ||
4f186f8b | 3005 | if (!dm_suspended_md(md)) |
cf222b37 | 3006 | goto out; |
cf222b37 | 3007 | |
ffcc3936 MS |
3008 | if (dm_suspended_internally_md(md)) { |
3009 | /* already internally suspended, wait for internal resume */ | |
3010 | mutex_unlock(&md->suspend_lock); | |
3011 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
3012 | if (r) | |
3013 | return r; | |
3014 | goto retry; | |
3015 | } | |
3016 | ||
a12f5d48 | 3017 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
2ca3310e | 3018 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 3019 | goto out; |
1da177e4 | 3020 | |
ffcc3936 | 3021 | r = __dm_resume(md, map); |
8757b776 MB |
3022 | if (r) |
3023 | goto out; | |
2ca3310e | 3024 | |
2ca3310e AK |
3025 | clear_bit(DMF_SUSPENDED, &md->flags); |
3026 | ||
cf222b37 AK |
3027 | r = 0; |
3028 | out: | |
e61290a4 | 3029 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 3030 | |
cf222b37 | 3031 | return r; |
1da177e4 LT |
3032 | } |
3033 | ||
fd2ed4d2 MP |
3034 | /* |
3035 | * Internal suspend/resume works like userspace-driven suspend. It waits | |
3036 | * until all bios finish and prevents issuing new bios to the target drivers. | |
3037 | * It may be used only from the kernel. | |
fd2ed4d2 MP |
3038 | */ |
3039 | ||
ffcc3936 | 3040 | static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags) |
fd2ed4d2 | 3041 | { |
ffcc3936 MS |
3042 | struct dm_table *map = NULL; |
3043 | ||
96b26c8c | 3044 | if (md->internal_suspend_count++) |
ffcc3936 MS |
3045 | return; /* nested internal suspend */ |
3046 | ||
3047 | if (dm_suspended_md(md)) { | |
3048 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3049 | return; /* nest suspend */ | |
3050 | } | |
3051 | ||
a12f5d48 | 3052 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
ffcc3936 MS |
3053 | |
3054 | /* | |
3055 | * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is | |
3056 | * supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend | |
3057 | * would require changing .presuspend to return an error -- avoid this | |
3058 | * until there is a need for more elaborate variants of internal suspend. | |
3059 | */ | |
3060 | (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE); | |
3061 | ||
3062 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3063 | ||
3064 | dm_table_postsuspend_targets(map); | |
3065 | } | |
3066 | ||
3067 | static void __dm_internal_resume(struct mapped_device *md) | |
3068 | { | |
96b26c8c MP |
3069 | BUG_ON(!md->internal_suspend_count); |
3070 | ||
3071 | if (--md->internal_suspend_count) | |
ffcc3936 MS |
3072 | return; /* resume from nested internal suspend */ |
3073 | ||
fd2ed4d2 | 3074 | if (dm_suspended_md(md)) |
ffcc3936 MS |
3075 | goto done; /* resume from nested suspend */ |
3076 | ||
3077 | /* | |
3078 | * NOTE: existing callers don't need to call dm_table_resume_targets | |
3079 | * (which may fail -- so best to avoid it for now by passing NULL map) | |
3080 | */ | |
3081 | (void) __dm_resume(md, NULL); | |
3082 | ||
3083 | done: | |
3084 | clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3085 | smp_mb__after_atomic(); | |
3086 | wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY); | |
3087 | } | |
3088 | ||
3089 | void dm_internal_suspend_noflush(struct mapped_device *md) | |
3090 | { | |
3091 | mutex_lock(&md->suspend_lock); | |
3092 | __dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG); | |
3093 | mutex_unlock(&md->suspend_lock); | |
3094 | } | |
3095 | EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush); | |
3096 | ||
3097 | void dm_internal_resume(struct mapped_device *md) | |
3098 | { | |
3099 | mutex_lock(&md->suspend_lock); | |
3100 | __dm_internal_resume(md); | |
3101 | mutex_unlock(&md->suspend_lock); | |
3102 | } | |
3103 | EXPORT_SYMBOL_GPL(dm_internal_resume); | |
3104 | ||
3105 | /* | |
3106 | * Fast variants of internal suspend/resume hold md->suspend_lock, | |
3107 | * which prevents interaction with userspace-driven suspend. | |
3108 | */ | |
3109 | ||
3110 | void dm_internal_suspend_fast(struct mapped_device *md) | |
3111 | { | |
3112 | mutex_lock(&md->suspend_lock); | |
3113 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) | |
fd2ed4d2 MP |
3114 | return; |
3115 | ||
3116 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); | |
3117 | synchronize_srcu(&md->io_barrier); | |
3118 | flush_workqueue(md->wq); | |
3119 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); | |
3120 | } | |
b735fede | 3121 | EXPORT_SYMBOL_GPL(dm_internal_suspend_fast); |
fd2ed4d2 | 3122 | |
ffcc3936 | 3123 | void dm_internal_resume_fast(struct mapped_device *md) |
fd2ed4d2 | 3124 | { |
ffcc3936 | 3125 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) |
fd2ed4d2 MP |
3126 | goto done; |
3127 | ||
3128 | dm_queue_flush(md); | |
3129 | ||
3130 | done: | |
3131 | mutex_unlock(&md->suspend_lock); | |
3132 | } | |
b735fede | 3133 | EXPORT_SYMBOL_GPL(dm_internal_resume_fast); |
fd2ed4d2 | 3134 | |
1da177e4 LT |
3135 | /*----------------------------------------------------------------- |
3136 | * Event notification. | |
3137 | *---------------------------------------------------------------*/ | |
3abf85b5 | 3138 | int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
60935eb2 | 3139 | unsigned cookie) |
69267a30 | 3140 | { |
60935eb2 MB |
3141 | char udev_cookie[DM_COOKIE_LENGTH]; |
3142 | char *envp[] = { udev_cookie, NULL }; | |
3143 | ||
3144 | if (!cookie) | |
3abf85b5 | 3145 | return kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
60935eb2 MB |
3146 | else { |
3147 | snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", | |
3148 | DM_COOKIE_ENV_VAR_NAME, cookie); | |
3abf85b5 PR |
3149 | return kobject_uevent_env(&disk_to_dev(md->disk)->kobj, |
3150 | action, envp); | |
60935eb2 | 3151 | } |
69267a30 AK |
3152 | } |
3153 | ||
7a8c3d3b MA |
3154 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
3155 | { | |
3156 | return atomic_add_return(1, &md->uevent_seq); | |
3157 | } | |
3158 | ||
1da177e4 LT |
3159 | uint32_t dm_get_event_nr(struct mapped_device *md) |
3160 | { | |
3161 | return atomic_read(&md->event_nr); | |
3162 | } | |
3163 | ||
3164 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
3165 | { | |
3166 | return wait_event_interruptible(md->eventq, | |
3167 | (event_nr != atomic_read(&md->event_nr))); | |
3168 | } | |
3169 | ||
7a8c3d3b MA |
3170 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
3171 | { | |
3172 | unsigned long flags; | |
3173 | ||
3174 | spin_lock_irqsave(&md->uevent_lock, flags); | |
3175 | list_add(elist, &md->uevent_list); | |
3176 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
3177 | } | |
3178 | ||
1da177e4 LT |
3179 | /* |
3180 | * The gendisk is only valid as long as you have a reference | |
3181 | * count on 'md'. | |
3182 | */ | |
3183 | struct gendisk *dm_disk(struct mapped_device *md) | |
3184 | { | |
3185 | return md->disk; | |
3186 | } | |
3187 | ||
784aae73 MB |
3188 | struct kobject *dm_kobject(struct mapped_device *md) |
3189 | { | |
2995fa78 | 3190 | return &md->kobj_holder.kobj; |
784aae73 MB |
3191 | } |
3192 | ||
784aae73 MB |
3193 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) |
3194 | { | |
3195 | struct mapped_device *md; | |
3196 | ||
2995fa78 | 3197 | md = container_of(kobj, struct mapped_device, kobj_holder.kobj); |
784aae73 | 3198 | |
4d89b7b4 | 3199 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 3200 | dm_deleting_md(md)) |
4d89b7b4 MB |
3201 | return NULL; |
3202 | ||
784aae73 MB |
3203 | dm_get(md); |
3204 | return md; | |
3205 | } | |
3206 | ||
4f186f8b | 3207 | int dm_suspended_md(struct mapped_device *md) |
1da177e4 LT |
3208 | { |
3209 | return test_bit(DMF_SUSPENDED, &md->flags); | |
3210 | } | |
3211 | ||
ffcc3936 MS |
3212 | int dm_suspended_internally_md(struct mapped_device *md) |
3213 | { | |
3214 | return test_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3215 | } | |
3216 | ||
2c140a24 MP |
3217 | int dm_test_deferred_remove_flag(struct mapped_device *md) |
3218 | { | |
3219 | return test_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
3220 | } | |
3221 | ||
64dbce58 KU |
3222 | int dm_suspended(struct dm_target *ti) |
3223 | { | |
ecdb2e25 | 3224 | return dm_suspended_md(dm_table_get_md(ti->table)); |
64dbce58 KU |
3225 | } |
3226 | EXPORT_SYMBOL_GPL(dm_suspended); | |
3227 | ||
2e93ccc1 KU |
3228 | int dm_noflush_suspending(struct dm_target *ti) |
3229 | { | |
ecdb2e25 | 3230 | return __noflush_suspending(dm_table_get_md(ti->table)); |
2e93ccc1 KU |
3231 | } |
3232 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
3233 | ||
c0820cf5 | 3234 | struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, unsigned per_bio_data_size) |
e6ee8c0b | 3235 | { |
5f015204 JN |
3236 | struct dm_md_mempools *pools = kzalloc(sizeof(*pools), GFP_KERNEL); |
3237 | struct kmem_cache *cachep; | |
e5863d9a | 3238 | unsigned int pool_size = 0; |
5f015204 | 3239 | unsigned int front_pad; |
e6ee8c0b KU |
3240 | |
3241 | if (!pools) | |
3242 | return NULL; | |
3243 | ||
e5863d9a MS |
3244 | switch (type) { |
3245 | case DM_TYPE_BIO_BASED: | |
5f015204 | 3246 | cachep = _io_cache; |
e8603136 | 3247 | pool_size = dm_get_reserved_bio_based_ios(); |
5f015204 | 3248 | front_pad = roundup(per_bio_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone); |
e5863d9a MS |
3249 | break; |
3250 | case DM_TYPE_REQUEST_BASED: | |
f4790826 | 3251 | pool_size = dm_get_reserved_rq_based_ios(); |
1ae49ea2 MS |
3252 | pools->rq_pool = mempool_create_slab_pool(pool_size, _rq_cache); |
3253 | if (!pools->rq_pool) | |
3254 | goto out; | |
e5863d9a MS |
3255 | /* fall through to setup remaining rq-based pools */ |
3256 | case DM_TYPE_MQ_REQUEST_BASED: | |
3257 | cachep = _rq_tio_cache; | |
3258 | if (!pool_size) | |
3259 | pool_size = dm_get_reserved_rq_based_ios(); | |
5f015204 JN |
3260 | front_pad = offsetof(struct dm_rq_clone_bio_info, clone); |
3261 | /* per_bio_data_size is not used. See __bind_mempools(). */ | |
3262 | WARN_ON(per_bio_data_size != 0); | |
e5863d9a MS |
3263 | break; |
3264 | default: | |
5f015204 | 3265 | goto out; |
e5863d9a | 3266 | } |
e6ee8c0b | 3267 | |
6cfa5857 | 3268 | pools->io_pool = mempool_create_slab_pool(pool_size, cachep); |
5f015204 JN |
3269 | if (!pools->io_pool) |
3270 | goto out; | |
e6ee8c0b | 3271 | |
3d8aab2d | 3272 | pools->bs = bioset_create_nobvec(pool_size, front_pad); |
e6ee8c0b | 3273 | if (!pools->bs) |
5f015204 | 3274 | goto out; |
e6ee8c0b | 3275 | |
a91a2785 | 3276 | if (integrity && bioset_integrity_create(pools->bs, pool_size)) |
5f015204 | 3277 | goto out; |
a91a2785 | 3278 | |
e6ee8c0b KU |
3279 | return pools; |
3280 | ||
5f015204 JN |
3281 | out: |
3282 | dm_free_md_mempools(pools); | |
e6ee8c0b KU |
3283 | |
3284 | return NULL; | |
3285 | } | |
3286 | ||
3287 | void dm_free_md_mempools(struct dm_md_mempools *pools) | |
3288 | { | |
3289 | if (!pools) | |
3290 | return; | |
3291 | ||
3292 | if (pools->io_pool) | |
3293 | mempool_destroy(pools->io_pool); | |
3294 | ||
1ae49ea2 MS |
3295 | if (pools->rq_pool) |
3296 | mempool_destroy(pools->rq_pool); | |
3297 | ||
e6ee8c0b KU |
3298 | if (pools->bs) |
3299 | bioset_free(pools->bs); | |
3300 | ||
3301 | kfree(pools); | |
3302 | } | |
3303 | ||
83d5cde4 | 3304 | static const struct block_device_operations dm_blk_dops = { |
1da177e4 LT |
3305 | .open = dm_blk_open, |
3306 | .release = dm_blk_close, | |
aa129a22 | 3307 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 3308 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
3309 | .owner = THIS_MODULE |
3310 | }; | |
3311 | ||
1da177e4 LT |
3312 | /* |
3313 | * module hooks | |
3314 | */ | |
3315 | module_init(dm_init); | |
3316 | module_exit(dm_exit); | |
3317 | ||
3318 | module_param(major, uint, 0); | |
3319 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
f4790826 | 3320 | |
e8603136 MS |
3321 | module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR); |
3322 | MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools"); | |
3323 | ||
f4790826 MS |
3324 | module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR); |
3325 | MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools"); | |
3326 | ||
1da177e4 LT |
3327 | MODULE_DESCRIPTION(DM_NAME " driver"); |
3328 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
3329 | MODULE_LICENSE("GPL"); |