Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. | |
784aae73 | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include "dm.h" | |
51e5b2bd | 9 | #include "dm-uevent.h" |
1da177e4 LT |
10 | |
11 | #include <linux/init.h> | |
12 | #include <linux/module.h> | |
48c9c27b | 13 | #include <linux/mutex.h> |
1da177e4 LT |
14 | #include <linux/moduleparam.h> |
15 | #include <linux/blkpg.h> | |
16 | #include <linux/bio.h> | |
1da177e4 LT |
17 | #include <linux/mempool.h> |
18 | #include <linux/slab.h> | |
19 | #include <linux/idr.h> | |
3ac51e74 | 20 | #include <linux/hdreg.h> |
3f77316d | 21 | #include <linux/delay.h> |
ffcc3936 | 22 | #include <linux/wait.h> |
2eb6e1e3 | 23 | #include <linux/kthread.h> |
de3ec86d | 24 | #include <linux/elevator.h> /* for rq_end_sector() */ |
55782138 LZ |
25 | |
26 | #include <trace/events/block.h> | |
1da177e4 | 27 | |
72d94861 AK |
28 | #define DM_MSG_PREFIX "core" |
29 | ||
71a16736 NK |
30 | #ifdef CONFIG_PRINTK |
31 | /* | |
32 | * ratelimit state to be used in DMXXX_LIMIT(). | |
33 | */ | |
34 | DEFINE_RATELIMIT_STATE(dm_ratelimit_state, | |
35 | DEFAULT_RATELIMIT_INTERVAL, | |
36 | DEFAULT_RATELIMIT_BURST); | |
37 | EXPORT_SYMBOL(dm_ratelimit_state); | |
38 | #endif | |
39 | ||
60935eb2 MB |
40 | /* |
41 | * Cookies are numeric values sent with CHANGE and REMOVE | |
42 | * uevents while resuming, removing or renaming the device. | |
43 | */ | |
44 | #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" | |
45 | #define DM_COOKIE_LENGTH 24 | |
46 | ||
1da177e4 LT |
47 | static const char *_name = DM_NAME; |
48 | ||
49 | static unsigned int major = 0; | |
50 | static unsigned int _major = 0; | |
51 | ||
d15b774c AK |
52 | static DEFINE_IDR(_minor_idr); |
53 | ||
f32c10b0 | 54 | static DEFINE_SPINLOCK(_minor_lock); |
2c140a24 MP |
55 | |
56 | static void do_deferred_remove(struct work_struct *w); | |
57 | ||
58 | static DECLARE_WORK(deferred_remove_work, do_deferred_remove); | |
59 | ||
acfe0ad7 MP |
60 | static struct workqueue_struct *deferred_remove_workqueue; |
61 | ||
1da177e4 | 62 | /* |
8fbf26ad | 63 | * For bio-based dm. |
1da177e4 LT |
64 | * One of these is allocated per bio. |
65 | */ | |
66 | struct dm_io { | |
67 | struct mapped_device *md; | |
68 | int error; | |
1da177e4 | 69 | atomic_t io_count; |
6ae2fa67 | 70 | struct bio *bio; |
3eaf840e | 71 | unsigned long start_time; |
f88fb981 | 72 | spinlock_t endio_lock; |
fd2ed4d2 | 73 | struct dm_stats_aux stats_aux; |
1da177e4 LT |
74 | }; |
75 | ||
8fbf26ad KU |
76 | /* |
77 | * For request-based dm. | |
78 | * One of these is allocated per request. | |
79 | */ | |
80 | struct dm_rq_target_io { | |
81 | struct mapped_device *md; | |
82 | struct dm_target *ti; | |
1ae49ea2 | 83 | struct request *orig, *clone; |
2eb6e1e3 | 84 | struct kthread_work work; |
8fbf26ad KU |
85 | int error; |
86 | union map_info info; | |
87 | }; | |
88 | ||
89 | /* | |
94818742 KO |
90 | * For request-based dm - the bio clones we allocate are embedded in these |
91 | * structs. | |
92 | * | |
93 | * We allocate these with bio_alloc_bioset, using the front_pad parameter when | |
94 | * the bioset is created - this means the bio has to come at the end of the | |
95 | * struct. | |
8fbf26ad KU |
96 | */ |
97 | struct dm_rq_clone_bio_info { | |
98 | struct bio *orig; | |
cec47e3d | 99 | struct dm_rq_target_io *tio; |
94818742 | 100 | struct bio clone; |
8fbf26ad KU |
101 | }; |
102 | ||
cec47e3d KU |
103 | union map_info *dm_get_rq_mapinfo(struct request *rq) |
104 | { | |
105 | if (rq && rq->end_io_data) | |
106 | return &((struct dm_rq_target_io *)rq->end_io_data)->info; | |
107 | return NULL; | |
108 | } | |
109 | EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo); | |
110 | ||
ba61fdd1 JM |
111 | #define MINOR_ALLOCED ((void *)-1) |
112 | ||
1da177e4 LT |
113 | /* |
114 | * Bits for the md->flags field. | |
115 | */ | |
1eb787ec | 116 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
1da177e4 | 117 | #define DMF_SUSPENDED 1 |
aa8d7c2f | 118 | #define DMF_FROZEN 2 |
fba9f90e | 119 | #define DMF_FREEING 3 |
5c6bd75d | 120 | #define DMF_DELETING 4 |
2e93ccc1 | 121 | #define DMF_NOFLUSH_SUSPENDING 5 |
d5b9dd04 | 122 | #define DMF_MERGE_IS_OPTIONAL 6 |
2c140a24 | 123 | #define DMF_DEFERRED_REMOVE 7 |
ffcc3936 | 124 | #define DMF_SUSPENDED_INTERNALLY 8 |
1da177e4 | 125 | |
83d5e5b0 MP |
126 | /* |
127 | * A dummy definition to make RCU happy. | |
128 | * struct dm_table should never be dereferenced in this file. | |
129 | */ | |
130 | struct dm_table { | |
131 | int undefined__; | |
132 | }; | |
133 | ||
304f3f6a MB |
134 | /* |
135 | * Work processed by per-device workqueue. | |
136 | */ | |
1da177e4 | 137 | struct mapped_device { |
83d5e5b0 | 138 | struct srcu_struct io_barrier; |
e61290a4 | 139 | struct mutex suspend_lock; |
1da177e4 | 140 | atomic_t holders; |
5c6bd75d | 141 | atomic_t open_count; |
1da177e4 | 142 | |
2a7faeb1 MP |
143 | /* |
144 | * The current mapping. | |
145 | * Use dm_get_live_table{_fast} or take suspend_lock for | |
146 | * dereference. | |
147 | */ | |
6fa99520 | 148 | struct dm_table __rcu *map; |
2a7faeb1 | 149 | |
86f1152b BM |
150 | struct list_head table_devices; |
151 | struct mutex table_devices_lock; | |
152 | ||
1da177e4 LT |
153 | unsigned long flags; |
154 | ||
165125e1 | 155 | struct request_queue *queue; |
a5664dad | 156 | unsigned type; |
4a0b4ddf | 157 | /* Protect queue and type against concurrent access. */ |
a5664dad MS |
158 | struct mutex type_lock; |
159 | ||
36a0456f AK |
160 | struct target_type *immutable_target_type; |
161 | ||
1da177e4 | 162 | struct gendisk *disk; |
7e51f257 | 163 | char name[16]; |
1da177e4 LT |
164 | |
165 | void *interface_ptr; | |
166 | ||
167 | /* | |
168 | * A list of ios that arrived while we were suspended. | |
169 | */ | |
316d315b | 170 | atomic_t pending[2]; |
1da177e4 | 171 | wait_queue_head_t wait; |
53d5914f | 172 | struct work_struct work; |
74859364 | 173 | struct bio_list deferred; |
022c2611 | 174 | spinlock_t deferred_lock; |
1da177e4 | 175 | |
af7e466a | 176 | /* |
29e4013d | 177 | * Processing queue (flush) |
304f3f6a MB |
178 | */ |
179 | struct workqueue_struct *wq; | |
180 | ||
1da177e4 LT |
181 | /* |
182 | * io objects are allocated from here. | |
183 | */ | |
184 | mempool_t *io_pool; | |
1ae49ea2 | 185 | mempool_t *rq_pool; |
1da177e4 | 186 | |
9faf400f SB |
187 | struct bio_set *bs; |
188 | ||
1da177e4 LT |
189 | /* |
190 | * Event handling. | |
191 | */ | |
192 | atomic_t event_nr; | |
193 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
194 | atomic_t uevent_seq; |
195 | struct list_head uevent_list; | |
196 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
197 | |
198 | /* | |
199 | * freeze/thaw support require holding onto a super block | |
200 | */ | |
201 | struct super_block *frozen_sb; | |
db8fef4f | 202 | struct block_device *bdev; |
3ac51e74 DW |
203 | |
204 | /* forced geometry settings */ | |
205 | struct hd_geometry geometry; | |
784aae73 | 206 | |
2995fa78 MP |
207 | /* kobject and completion */ |
208 | struct dm_kobject_holder kobj_holder; | |
be35f486 | 209 | |
d87f4c14 TH |
210 | /* zero-length flush that will be cloned and submitted to targets */ |
211 | struct bio flush_bio; | |
fd2ed4d2 | 212 | |
96b26c8c MP |
213 | /* the number of internal suspends */ |
214 | unsigned internal_suspend_count; | |
215 | ||
fd2ed4d2 | 216 | struct dm_stats stats; |
2eb6e1e3 KB |
217 | |
218 | struct kthread_worker kworker; | |
219 | struct task_struct *kworker_task; | |
de3ec86d MS |
220 | |
221 | /* for request-based merge heuristic in dm_request_fn() */ | |
222 | sector_t last_rq_pos; | |
223 | int last_rq_rw; | |
1da177e4 LT |
224 | }; |
225 | ||
e6ee8c0b KU |
226 | /* |
227 | * For mempools pre-allocation at the table loading time. | |
228 | */ | |
229 | struct dm_md_mempools { | |
230 | mempool_t *io_pool; | |
1ae49ea2 | 231 | mempool_t *rq_pool; |
e6ee8c0b KU |
232 | struct bio_set *bs; |
233 | }; | |
234 | ||
86f1152b BM |
235 | struct table_device { |
236 | struct list_head list; | |
237 | atomic_t count; | |
238 | struct dm_dev dm_dev; | |
239 | }; | |
240 | ||
6cfa5857 MS |
241 | #define RESERVED_BIO_BASED_IOS 16 |
242 | #define RESERVED_REQUEST_BASED_IOS 256 | |
f4790826 | 243 | #define RESERVED_MAX_IOS 1024 |
e18b890b | 244 | static struct kmem_cache *_io_cache; |
8fbf26ad | 245 | static struct kmem_cache *_rq_tio_cache; |
1ae49ea2 | 246 | static struct kmem_cache *_rq_cache; |
94818742 | 247 | |
e8603136 MS |
248 | /* |
249 | * Bio-based DM's mempools' reserved IOs set by the user. | |
250 | */ | |
251 | static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; | |
252 | ||
f4790826 MS |
253 | /* |
254 | * Request-based DM's mempools' reserved IOs set by the user. | |
255 | */ | |
256 | static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS; | |
257 | ||
09c2d531 | 258 | static unsigned __dm_get_module_param(unsigned *module_param, |
f4790826 MS |
259 | unsigned def, unsigned max) |
260 | { | |
09c2d531 MS |
261 | unsigned param = ACCESS_ONCE(*module_param); |
262 | unsigned modified_param = 0; | |
f4790826 | 263 | |
09c2d531 MS |
264 | if (!param) |
265 | modified_param = def; | |
266 | else if (param > max) | |
267 | modified_param = max; | |
f4790826 | 268 | |
09c2d531 MS |
269 | if (modified_param) { |
270 | (void)cmpxchg(module_param, param, modified_param); | |
271 | param = modified_param; | |
f4790826 MS |
272 | } |
273 | ||
09c2d531 | 274 | return param; |
f4790826 MS |
275 | } |
276 | ||
e8603136 MS |
277 | unsigned dm_get_reserved_bio_based_ios(void) |
278 | { | |
09c2d531 | 279 | return __dm_get_module_param(&reserved_bio_based_ios, |
e8603136 MS |
280 | RESERVED_BIO_BASED_IOS, RESERVED_MAX_IOS); |
281 | } | |
282 | EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); | |
283 | ||
f4790826 MS |
284 | unsigned dm_get_reserved_rq_based_ios(void) |
285 | { | |
09c2d531 | 286 | return __dm_get_module_param(&reserved_rq_based_ios, |
f4790826 MS |
287 | RESERVED_REQUEST_BASED_IOS, RESERVED_MAX_IOS); |
288 | } | |
289 | EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios); | |
290 | ||
1da177e4 LT |
291 | static int __init local_init(void) |
292 | { | |
51157b4a | 293 | int r = -ENOMEM; |
1da177e4 | 294 | |
1da177e4 | 295 | /* allocate a slab for the dm_ios */ |
028867ac | 296 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 | 297 | if (!_io_cache) |
51157b4a | 298 | return r; |
1da177e4 | 299 | |
8fbf26ad KU |
300 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
301 | if (!_rq_tio_cache) | |
dba14160 | 302 | goto out_free_io_cache; |
8fbf26ad | 303 | |
1ae49ea2 MS |
304 | _rq_cache = kmem_cache_create("dm_clone_request", sizeof(struct request), |
305 | __alignof__(struct request), 0, NULL); | |
306 | if (!_rq_cache) | |
307 | goto out_free_rq_tio_cache; | |
308 | ||
51e5b2bd | 309 | r = dm_uevent_init(); |
51157b4a | 310 | if (r) |
1ae49ea2 | 311 | goto out_free_rq_cache; |
51e5b2bd | 312 | |
acfe0ad7 MP |
313 | deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1); |
314 | if (!deferred_remove_workqueue) { | |
315 | r = -ENOMEM; | |
316 | goto out_uevent_exit; | |
317 | } | |
318 | ||
1da177e4 LT |
319 | _major = major; |
320 | r = register_blkdev(_major, _name); | |
51157b4a | 321 | if (r < 0) |
acfe0ad7 | 322 | goto out_free_workqueue; |
1da177e4 LT |
323 | |
324 | if (!_major) | |
325 | _major = r; | |
326 | ||
327 | return 0; | |
51157b4a | 328 | |
acfe0ad7 MP |
329 | out_free_workqueue: |
330 | destroy_workqueue(deferred_remove_workqueue); | |
51157b4a KU |
331 | out_uevent_exit: |
332 | dm_uevent_exit(); | |
1ae49ea2 MS |
333 | out_free_rq_cache: |
334 | kmem_cache_destroy(_rq_cache); | |
8fbf26ad KU |
335 | out_free_rq_tio_cache: |
336 | kmem_cache_destroy(_rq_tio_cache); | |
51157b4a KU |
337 | out_free_io_cache: |
338 | kmem_cache_destroy(_io_cache); | |
339 | ||
340 | return r; | |
1da177e4 LT |
341 | } |
342 | ||
343 | static void local_exit(void) | |
344 | { | |
2c140a24 | 345 | flush_scheduled_work(); |
acfe0ad7 | 346 | destroy_workqueue(deferred_remove_workqueue); |
2c140a24 | 347 | |
1ae49ea2 | 348 | kmem_cache_destroy(_rq_cache); |
8fbf26ad | 349 | kmem_cache_destroy(_rq_tio_cache); |
1da177e4 | 350 | kmem_cache_destroy(_io_cache); |
00d59405 | 351 | unregister_blkdev(_major, _name); |
51e5b2bd | 352 | dm_uevent_exit(); |
1da177e4 LT |
353 | |
354 | _major = 0; | |
355 | ||
356 | DMINFO("cleaned up"); | |
357 | } | |
358 | ||
b9249e55 | 359 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
360 | local_init, |
361 | dm_target_init, | |
362 | dm_linear_init, | |
363 | dm_stripe_init, | |
952b3557 | 364 | dm_io_init, |
945fa4d2 | 365 | dm_kcopyd_init, |
1da177e4 | 366 | dm_interface_init, |
fd2ed4d2 | 367 | dm_statistics_init, |
1da177e4 LT |
368 | }; |
369 | ||
b9249e55 | 370 | static void (*_exits[])(void) = { |
1da177e4 LT |
371 | local_exit, |
372 | dm_target_exit, | |
373 | dm_linear_exit, | |
374 | dm_stripe_exit, | |
952b3557 | 375 | dm_io_exit, |
945fa4d2 | 376 | dm_kcopyd_exit, |
1da177e4 | 377 | dm_interface_exit, |
fd2ed4d2 | 378 | dm_statistics_exit, |
1da177e4 LT |
379 | }; |
380 | ||
381 | static int __init dm_init(void) | |
382 | { | |
383 | const int count = ARRAY_SIZE(_inits); | |
384 | ||
385 | int r, i; | |
386 | ||
387 | for (i = 0; i < count; i++) { | |
388 | r = _inits[i](); | |
389 | if (r) | |
390 | goto bad; | |
391 | } | |
392 | ||
393 | return 0; | |
394 | ||
395 | bad: | |
396 | while (i--) | |
397 | _exits[i](); | |
398 | ||
399 | return r; | |
400 | } | |
401 | ||
402 | static void __exit dm_exit(void) | |
403 | { | |
404 | int i = ARRAY_SIZE(_exits); | |
405 | ||
406 | while (i--) | |
407 | _exits[i](); | |
d15b774c AK |
408 | |
409 | /* | |
410 | * Should be empty by this point. | |
411 | */ | |
d15b774c | 412 | idr_destroy(&_minor_idr); |
1da177e4 LT |
413 | } |
414 | ||
415 | /* | |
416 | * Block device functions | |
417 | */ | |
432a212c MA |
418 | int dm_deleting_md(struct mapped_device *md) |
419 | { | |
420 | return test_bit(DMF_DELETING, &md->flags); | |
421 | } | |
422 | ||
fe5f9f2c | 423 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
424 | { |
425 | struct mapped_device *md; | |
426 | ||
fba9f90e JM |
427 | spin_lock(&_minor_lock); |
428 | ||
fe5f9f2c | 429 | md = bdev->bd_disk->private_data; |
fba9f90e JM |
430 | if (!md) |
431 | goto out; | |
432 | ||
5c6bd75d | 433 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 434 | dm_deleting_md(md)) { |
fba9f90e JM |
435 | md = NULL; |
436 | goto out; | |
437 | } | |
438 | ||
1da177e4 | 439 | dm_get(md); |
5c6bd75d | 440 | atomic_inc(&md->open_count); |
fba9f90e JM |
441 | out: |
442 | spin_unlock(&_minor_lock); | |
443 | ||
444 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
445 | } |
446 | ||
db2a144b | 447 | static void dm_blk_close(struct gendisk *disk, fmode_t mode) |
1da177e4 | 448 | { |
63a4f065 | 449 | struct mapped_device *md; |
6e9624b8 | 450 | |
4a1aeb98 MB |
451 | spin_lock(&_minor_lock); |
452 | ||
63a4f065 MS |
453 | md = disk->private_data; |
454 | if (WARN_ON(!md)) | |
455 | goto out; | |
456 | ||
2c140a24 MP |
457 | if (atomic_dec_and_test(&md->open_count) && |
458 | (test_bit(DMF_DEFERRED_REMOVE, &md->flags))) | |
acfe0ad7 | 459 | queue_work(deferred_remove_workqueue, &deferred_remove_work); |
2c140a24 | 460 | |
1da177e4 | 461 | dm_put(md); |
63a4f065 | 462 | out: |
4a1aeb98 | 463 | spin_unlock(&_minor_lock); |
1da177e4 LT |
464 | } |
465 | ||
5c6bd75d AK |
466 | int dm_open_count(struct mapped_device *md) |
467 | { | |
468 | return atomic_read(&md->open_count); | |
469 | } | |
470 | ||
471 | /* | |
472 | * Guarantees nothing is using the device before it's deleted. | |
473 | */ | |
2c140a24 | 474 | int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred) |
5c6bd75d AK |
475 | { |
476 | int r = 0; | |
477 | ||
478 | spin_lock(&_minor_lock); | |
479 | ||
2c140a24 | 480 | if (dm_open_count(md)) { |
5c6bd75d | 481 | r = -EBUSY; |
2c140a24 MP |
482 | if (mark_deferred) |
483 | set_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
484 | } else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags)) | |
485 | r = -EEXIST; | |
5c6bd75d AK |
486 | else |
487 | set_bit(DMF_DELETING, &md->flags); | |
488 | ||
489 | spin_unlock(&_minor_lock); | |
490 | ||
491 | return r; | |
492 | } | |
493 | ||
2c140a24 MP |
494 | int dm_cancel_deferred_remove(struct mapped_device *md) |
495 | { | |
496 | int r = 0; | |
497 | ||
498 | spin_lock(&_minor_lock); | |
499 | ||
500 | if (test_bit(DMF_DELETING, &md->flags)) | |
501 | r = -EBUSY; | |
502 | else | |
503 | clear_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
504 | ||
505 | spin_unlock(&_minor_lock); | |
506 | ||
507 | return r; | |
508 | } | |
509 | ||
510 | static void do_deferred_remove(struct work_struct *w) | |
511 | { | |
512 | dm_deferred_remove(); | |
513 | } | |
514 | ||
fd2ed4d2 MP |
515 | sector_t dm_get_size(struct mapped_device *md) |
516 | { | |
517 | return get_capacity(md->disk); | |
518 | } | |
519 | ||
9974fa2c MS |
520 | struct request_queue *dm_get_md_queue(struct mapped_device *md) |
521 | { | |
522 | return md->queue; | |
523 | } | |
524 | ||
fd2ed4d2 MP |
525 | struct dm_stats *dm_get_stats(struct mapped_device *md) |
526 | { | |
527 | return &md->stats; | |
528 | } | |
529 | ||
3ac51e74 DW |
530 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
531 | { | |
532 | struct mapped_device *md = bdev->bd_disk->private_data; | |
533 | ||
534 | return dm_get_geometry(md, geo); | |
535 | } | |
536 | ||
fe5f9f2c | 537 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
aa129a22 MB |
538 | unsigned int cmd, unsigned long arg) |
539 | { | |
fe5f9f2c | 540 | struct mapped_device *md = bdev->bd_disk->private_data; |
83d5e5b0 | 541 | int srcu_idx; |
6c182cd8 | 542 | struct dm_table *map; |
aa129a22 MB |
543 | struct dm_target *tgt; |
544 | int r = -ENOTTY; | |
545 | ||
6c182cd8 | 546 | retry: |
83d5e5b0 MP |
547 | map = dm_get_live_table(md, &srcu_idx); |
548 | ||
aa129a22 MB |
549 | if (!map || !dm_table_get_size(map)) |
550 | goto out; | |
551 | ||
552 | /* We only support devices that have a single target */ | |
553 | if (dm_table_get_num_targets(map) != 1) | |
554 | goto out; | |
555 | ||
556 | tgt = dm_table_get_target(map, 0); | |
4d341d82 MS |
557 | if (!tgt->type->ioctl) |
558 | goto out; | |
aa129a22 | 559 | |
4f186f8b | 560 | if (dm_suspended_md(md)) { |
aa129a22 MB |
561 | r = -EAGAIN; |
562 | goto out; | |
563 | } | |
564 | ||
4d341d82 | 565 | r = tgt->type->ioctl(tgt, cmd, arg); |
aa129a22 MB |
566 | |
567 | out: | |
83d5e5b0 | 568 | dm_put_live_table(md, srcu_idx); |
aa129a22 | 569 | |
6c182cd8 HR |
570 | if (r == -ENOTCONN) { |
571 | msleep(10); | |
572 | goto retry; | |
573 | } | |
574 | ||
aa129a22 MB |
575 | return r; |
576 | } | |
577 | ||
028867ac | 578 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
579 | { |
580 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
581 | } | |
582 | ||
028867ac | 583 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
584 | { |
585 | mempool_free(io, md->io_pool); | |
586 | } | |
587 | ||
028867ac | 588 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 | 589 | { |
dba14160 | 590 | bio_put(&tio->clone); |
1da177e4 LT |
591 | } |
592 | ||
08885643 KU |
593 | static struct dm_rq_target_io *alloc_rq_tio(struct mapped_device *md, |
594 | gfp_t gfp_mask) | |
cec47e3d | 595 | { |
5f015204 | 596 | return mempool_alloc(md->io_pool, gfp_mask); |
cec47e3d KU |
597 | } |
598 | ||
599 | static void free_rq_tio(struct dm_rq_target_io *tio) | |
600 | { | |
5f015204 | 601 | mempool_free(tio, tio->md->io_pool); |
cec47e3d KU |
602 | } |
603 | ||
1ae49ea2 MS |
604 | static struct request *alloc_clone_request(struct mapped_device *md, |
605 | gfp_t gfp_mask) | |
606 | { | |
607 | return mempool_alloc(md->rq_pool, gfp_mask); | |
608 | } | |
609 | ||
610 | static void free_clone_request(struct mapped_device *md, struct request *rq) | |
611 | { | |
612 | mempool_free(rq, md->rq_pool); | |
613 | } | |
614 | ||
90abb8c4 KU |
615 | static int md_in_flight(struct mapped_device *md) |
616 | { | |
617 | return atomic_read(&md->pending[READ]) + | |
618 | atomic_read(&md->pending[WRITE]); | |
619 | } | |
620 | ||
3eaf840e JNN |
621 | static void start_io_acct(struct dm_io *io) |
622 | { | |
623 | struct mapped_device *md = io->md; | |
fd2ed4d2 | 624 | struct bio *bio = io->bio; |
c9959059 | 625 | int cpu; |
fd2ed4d2 | 626 | int rw = bio_data_dir(bio); |
3eaf840e JNN |
627 | |
628 | io->start_time = jiffies; | |
629 | ||
074a7aca TH |
630 | cpu = part_stat_lock(); |
631 | part_round_stats(cpu, &dm_disk(md)->part0); | |
632 | part_stat_unlock(); | |
1e9bb880 SL |
633 | atomic_set(&dm_disk(md)->part0.in_flight[rw], |
634 | atomic_inc_return(&md->pending[rw])); | |
fd2ed4d2 MP |
635 | |
636 | if (unlikely(dm_stats_used(&md->stats))) | |
4f024f37 | 637 | dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, |
fd2ed4d2 | 638 | bio_sectors(bio), false, 0, &io->stats_aux); |
3eaf840e JNN |
639 | } |
640 | ||
d221d2e7 | 641 | static void end_io_acct(struct dm_io *io) |
3eaf840e JNN |
642 | { |
643 | struct mapped_device *md = io->md; | |
644 | struct bio *bio = io->bio; | |
645 | unsigned long duration = jiffies - io->start_time; | |
18c0b223 | 646 | int pending; |
3eaf840e JNN |
647 | int rw = bio_data_dir(bio); |
648 | ||
18c0b223 | 649 | generic_end_io_acct(rw, &dm_disk(md)->part0, io->start_time); |
3eaf840e | 650 | |
fd2ed4d2 | 651 | if (unlikely(dm_stats_used(&md->stats))) |
4f024f37 | 652 | dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, |
fd2ed4d2 MP |
653 | bio_sectors(bio), true, duration, &io->stats_aux); |
654 | ||
af7e466a MP |
655 | /* |
656 | * After this is decremented the bio must not be touched if it is | |
d87f4c14 | 657 | * a flush. |
af7e466a | 658 | */ |
1e9bb880 SL |
659 | pending = atomic_dec_return(&md->pending[rw]); |
660 | atomic_set(&dm_disk(md)->part0.in_flight[rw], pending); | |
316d315b | 661 | pending += atomic_read(&md->pending[rw^0x1]); |
3eaf840e | 662 | |
d221d2e7 MP |
663 | /* nudge anyone waiting on suspend queue */ |
664 | if (!pending) | |
665 | wake_up(&md->wait); | |
3eaf840e JNN |
666 | } |
667 | ||
1da177e4 LT |
668 | /* |
669 | * Add the bio to the list of deferred io. | |
670 | */ | |
92c63902 | 671 | static void queue_io(struct mapped_device *md, struct bio *bio) |
1da177e4 | 672 | { |
05447420 | 673 | unsigned long flags; |
1da177e4 | 674 | |
05447420 | 675 | spin_lock_irqsave(&md->deferred_lock, flags); |
1da177e4 | 676 | bio_list_add(&md->deferred, bio); |
05447420 | 677 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
6a8736d1 | 678 | queue_work(md->wq, &md->work); |
1da177e4 LT |
679 | } |
680 | ||
681 | /* | |
682 | * Everyone (including functions in this file), should use this | |
683 | * function to access the md->map field, and make sure they call | |
83d5e5b0 | 684 | * dm_put_live_table() when finished. |
1da177e4 | 685 | */ |
83d5e5b0 | 686 | struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier) |
1da177e4 | 687 | { |
83d5e5b0 MP |
688 | *srcu_idx = srcu_read_lock(&md->io_barrier); |
689 | ||
690 | return srcu_dereference(md->map, &md->io_barrier); | |
691 | } | |
1da177e4 | 692 | |
83d5e5b0 MP |
693 | void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier) |
694 | { | |
695 | srcu_read_unlock(&md->io_barrier, srcu_idx); | |
696 | } | |
697 | ||
698 | void dm_sync_table(struct mapped_device *md) | |
699 | { | |
700 | synchronize_srcu(&md->io_barrier); | |
701 | synchronize_rcu_expedited(); | |
702 | } | |
703 | ||
704 | /* | |
705 | * A fast alternative to dm_get_live_table/dm_put_live_table. | |
706 | * The caller must not block between these two functions. | |
707 | */ | |
708 | static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU) | |
709 | { | |
710 | rcu_read_lock(); | |
711 | return rcu_dereference(md->map); | |
712 | } | |
1da177e4 | 713 | |
83d5e5b0 MP |
714 | static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU) |
715 | { | |
716 | rcu_read_unlock(); | |
1da177e4 LT |
717 | } |
718 | ||
86f1152b BM |
719 | /* |
720 | * Open a table device so we can use it as a map destination. | |
721 | */ | |
722 | static int open_table_device(struct table_device *td, dev_t dev, | |
723 | struct mapped_device *md) | |
724 | { | |
725 | static char *_claim_ptr = "I belong to device-mapper"; | |
726 | struct block_device *bdev; | |
727 | ||
728 | int r; | |
729 | ||
730 | BUG_ON(td->dm_dev.bdev); | |
731 | ||
732 | bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _claim_ptr); | |
733 | if (IS_ERR(bdev)) | |
734 | return PTR_ERR(bdev); | |
735 | ||
736 | r = bd_link_disk_holder(bdev, dm_disk(md)); | |
737 | if (r) { | |
738 | blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL); | |
739 | return r; | |
740 | } | |
741 | ||
742 | td->dm_dev.bdev = bdev; | |
743 | return 0; | |
744 | } | |
745 | ||
746 | /* | |
747 | * Close a table device that we've been using. | |
748 | */ | |
749 | static void close_table_device(struct table_device *td, struct mapped_device *md) | |
750 | { | |
751 | if (!td->dm_dev.bdev) | |
752 | return; | |
753 | ||
754 | bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md)); | |
755 | blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL); | |
756 | td->dm_dev.bdev = NULL; | |
757 | } | |
758 | ||
759 | static struct table_device *find_table_device(struct list_head *l, dev_t dev, | |
760 | fmode_t mode) { | |
761 | struct table_device *td; | |
762 | ||
763 | list_for_each_entry(td, l, list) | |
764 | if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode) | |
765 | return td; | |
766 | ||
767 | return NULL; | |
768 | } | |
769 | ||
770 | int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, | |
771 | struct dm_dev **result) { | |
772 | int r; | |
773 | struct table_device *td; | |
774 | ||
775 | mutex_lock(&md->table_devices_lock); | |
776 | td = find_table_device(&md->table_devices, dev, mode); | |
777 | if (!td) { | |
778 | td = kmalloc(sizeof(*td), GFP_KERNEL); | |
779 | if (!td) { | |
780 | mutex_unlock(&md->table_devices_lock); | |
781 | return -ENOMEM; | |
782 | } | |
783 | ||
784 | td->dm_dev.mode = mode; | |
785 | td->dm_dev.bdev = NULL; | |
786 | ||
787 | if ((r = open_table_device(td, dev, md))) { | |
788 | mutex_unlock(&md->table_devices_lock); | |
789 | kfree(td); | |
790 | return r; | |
791 | } | |
792 | ||
793 | format_dev_t(td->dm_dev.name, dev); | |
794 | ||
795 | atomic_set(&td->count, 0); | |
796 | list_add(&td->list, &md->table_devices); | |
797 | } | |
798 | atomic_inc(&td->count); | |
799 | mutex_unlock(&md->table_devices_lock); | |
800 | ||
801 | *result = &td->dm_dev; | |
802 | return 0; | |
803 | } | |
804 | EXPORT_SYMBOL_GPL(dm_get_table_device); | |
805 | ||
806 | void dm_put_table_device(struct mapped_device *md, struct dm_dev *d) | |
807 | { | |
808 | struct table_device *td = container_of(d, struct table_device, dm_dev); | |
809 | ||
810 | mutex_lock(&md->table_devices_lock); | |
811 | if (atomic_dec_and_test(&td->count)) { | |
812 | close_table_device(td, md); | |
813 | list_del(&td->list); | |
814 | kfree(td); | |
815 | } | |
816 | mutex_unlock(&md->table_devices_lock); | |
817 | } | |
818 | EXPORT_SYMBOL(dm_put_table_device); | |
819 | ||
820 | static void free_table_devices(struct list_head *devices) | |
821 | { | |
822 | struct list_head *tmp, *next; | |
823 | ||
824 | list_for_each_safe(tmp, next, devices) { | |
825 | struct table_device *td = list_entry(tmp, struct table_device, list); | |
826 | ||
827 | DMWARN("dm_destroy: %s still exists with %d references", | |
828 | td->dm_dev.name, atomic_read(&td->count)); | |
829 | kfree(td); | |
830 | } | |
831 | } | |
832 | ||
3ac51e74 DW |
833 | /* |
834 | * Get the geometry associated with a dm device | |
835 | */ | |
836 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
837 | { | |
838 | *geo = md->geometry; | |
839 | ||
840 | return 0; | |
841 | } | |
842 | ||
843 | /* | |
844 | * Set the geometry of a device. | |
845 | */ | |
846 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
847 | { | |
848 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
849 | ||
850 | if (geo->start > sz) { | |
851 | DMWARN("Start sector is beyond the geometry limits."); | |
852 | return -EINVAL; | |
853 | } | |
854 | ||
855 | md->geometry = *geo; | |
856 | ||
857 | return 0; | |
858 | } | |
859 | ||
1da177e4 LT |
860 | /*----------------------------------------------------------------- |
861 | * CRUD START: | |
862 | * A more elegant soln is in the works that uses the queue | |
863 | * merge fn, unfortunately there are a couple of changes to | |
864 | * the block layer that I want to make for this. So in the | |
865 | * interests of getting something for people to use I give | |
866 | * you this clearly demarcated crap. | |
867 | *---------------------------------------------------------------*/ | |
868 | ||
2e93ccc1 KU |
869 | static int __noflush_suspending(struct mapped_device *md) |
870 | { | |
871 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
872 | } | |
873 | ||
1da177e4 LT |
874 | /* |
875 | * Decrements the number of outstanding ios that a bio has been | |
876 | * cloned into, completing the original io if necc. | |
877 | */ | |
858119e1 | 878 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 879 | { |
2e93ccc1 | 880 | unsigned long flags; |
b35f8caa MB |
881 | int io_error; |
882 | struct bio *bio; | |
883 | struct mapped_device *md = io->md; | |
2e93ccc1 KU |
884 | |
885 | /* Push-back supersedes any I/O errors */ | |
f88fb981 KU |
886 | if (unlikely(error)) { |
887 | spin_lock_irqsave(&io->endio_lock, flags); | |
888 | if (!(io->error > 0 && __noflush_suspending(md))) | |
889 | io->error = error; | |
890 | spin_unlock_irqrestore(&io->endio_lock, flags); | |
891 | } | |
1da177e4 LT |
892 | |
893 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
894 | if (io->error == DM_ENDIO_REQUEUE) { |
895 | /* | |
896 | * Target requested pushing back the I/O. | |
2e93ccc1 | 897 | */ |
022c2611 | 898 | spin_lock_irqsave(&md->deferred_lock, flags); |
6a8736d1 TH |
899 | if (__noflush_suspending(md)) |
900 | bio_list_add_head(&md->deferred, io->bio); | |
901 | else | |
2e93ccc1 KU |
902 | /* noflush suspend was interrupted. */ |
903 | io->error = -EIO; | |
022c2611 | 904 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
2e93ccc1 KU |
905 | } |
906 | ||
b35f8caa MB |
907 | io_error = io->error; |
908 | bio = io->bio; | |
6a8736d1 TH |
909 | end_io_acct(io); |
910 | free_io(md, io); | |
911 | ||
912 | if (io_error == DM_ENDIO_REQUEUE) | |
913 | return; | |
2e93ccc1 | 914 | |
4f024f37 | 915 | if ((bio->bi_rw & REQ_FLUSH) && bio->bi_iter.bi_size) { |
af7e466a | 916 | /* |
6a8736d1 TH |
917 | * Preflush done for flush with data, reissue |
918 | * without REQ_FLUSH. | |
af7e466a | 919 | */ |
6a8736d1 TH |
920 | bio->bi_rw &= ~REQ_FLUSH; |
921 | queue_io(md, bio); | |
af7e466a | 922 | } else { |
b372d360 | 923 | /* done with normal IO or empty flush */ |
0a82a8d1 | 924 | trace_block_bio_complete(md->queue, bio, io_error); |
b372d360 | 925 | bio_endio(bio, io_error); |
b35f8caa | 926 | } |
1da177e4 LT |
927 | } |
928 | } | |
929 | ||
7eee4ae2 MS |
930 | static void disable_write_same(struct mapped_device *md) |
931 | { | |
932 | struct queue_limits *limits = dm_get_queue_limits(md); | |
933 | ||
934 | /* device doesn't really support WRITE SAME, disable it */ | |
935 | limits->max_write_same_sectors = 0; | |
936 | } | |
937 | ||
6712ecf8 | 938 | static void clone_endio(struct bio *bio, int error) |
1da177e4 | 939 | { |
5164bece | 940 | int r = error; |
bfc6d41c | 941 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
b35f8caa | 942 | struct dm_io *io = tio->io; |
9faf400f | 943 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
944 | dm_endio_fn endio = tio->ti->type->end_io; |
945 | ||
1da177e4 LT |
946 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
947 | error = -EIO; | |
948 | ||
949 | if (endio) { | |
7de3ee57 | 950 | r = endio(tio->ti, bio, error); |
2e93ccc1 KU |
951 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
952 | /* | |
953 | * error and requeue request are handled | |
954 | * in dec_pending(). | |
955 | */ | |
1da177e4 | 956 | error = r; |
45cbcd79 KU |
957 | else if (r == DM_ENDIO_INCOMPLETE) |
958 | /* The target will handle the io */ | |
6712ecf8 | 959 | return; |
45cbcd79 KU |
960 | else if (r) { |
961 | DMWARN("unimplemented target endio return value: %d", r); | |
962 | BUG(); | |
963 | } | |
1da177e4 LT |
964 | } |
965 | ||
7eee4ae2 MS |
966 | if (unlikely(r == -EREMOTEIO && (bio->bi_rw & REQ_WRITE_SAME) && |
967 | !bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors)) | |
968 | disable_write_same(md); | |
969 | ||
9faf400f | 970 | free_tio(md, tio); |
b35f8caa | 971 | dec_pending(io, error); |
1da177e4 LT |
972 | } |
973 | ||
cec47e3d KU |
974 | /* |
975 | * Partial completion handling for request-based dm | |
976 | */ | |
977 | static void end_clone_bio(struct bio *clone, int error) | |
978 | { | |
bfc6d41c MP |
979 | struct dm_rq_clone_bio_info *info = |
980 | container_of(clone, struct dm_rq_clone_bio_info, clone); | |
cec47e3d KU |
981 | struct dm_rq_target_io *tio = info->tio; |
982 | struct bio *bio = info->orig; | |
4f024f37 | 983 | unsigned int nr_bytes = info->orig->bi_iter.bi_size; |
cec47e3d KU |
984 | |
985 | bio_put(clone); | |
986 | ||
987 | if (tio->error) | |
988 | /* | |
989 | * An error has already been detected on the request. | |
990 | * Once error occurred, just let clone->end_io() handle | |
991 | * the remainder. | |
992 | */ | |
993 | return; | |
994 | else if (error) { | |
995 | /* | |
996 | * Don't notice the error to the upper layer yet. | |
997 | * The error handling decision is made by the target driver, | |
998 | * when the request is completed. | |
999 | */ | |
1000 | tio->error = error; | |
1001 | return; | |
1002 | } | |
1003 | ||
1004 | /* | |
1005 | * I/O for the bio successfully completed. | |
1006 | * Notice the data completion to the upper layer. | |
1007 | */ | |
1008 | ||
1009 | /* | |
1010 | * bios are processed from the head of the list. | |
1011 | * So the completing bio should always be rq->bio. | |
1012 | * If it's not, something wrong is happening. | |
1013 | */ | |
1014 | if (tio->orig->bio != bio) | |
1015 | DMERR("bio completion is going in the middle of the request"); | |
1016 | ||
1017 | /* | |
1018 | * Update the original request. | |
1019 | * Do not use blk_end_request() here, because it may complete | |
1020 | * the original request before the clone, and break the ordering. | |
1021 | */ | |
1022 | blk_update_request(tio->orig, 0, nr_bytes); | |
1023 | } | |
1024 | ||
1025 | /* | |
1026 | * Don't touch any member of the md after calling this function because | |
1027 | * the md may be freed in dm_put() at the end of this function. | |
1028 | * Or do dm_get() before calling this function and dm_put() later. | |
1029 | */ | |
466d89a6 | 1030 | static void rq_completed(struct mapped_device *md, int rw, bool run_queue) |
cec47e3d | 1031 | { |
9a0e609e MS |
1032 | int nr_requests_pending; |
1033 | ||
b4324fee | 1034 | atomic_dec(&md->pending[rw]); |
cec47e3d KU |
1035 | |
1036 | /* nudge anyone waiting on suspend queue */ | |
9a0e609e MS |
1037 | nr_requests_pending = md_in_flight(md); |
1038 | if (!nr_requests_pending) | |
cec47e3d KU |
1039 | wake_up(&md->wait); |
1040 | ||
a8c32a5c JA |
1041 | /* |
1042 | * Run this off this callpath, as drivers could invoke end_io while | |
1043 | * inside their request_fn (and holding the queue lock). Calling | |
1044 | * back into ->request_fn() could deadlock attempting to grab the | |
1045 | * queue lock again. | |
1046 | */ | |
9a0e609e MS |
1047 | if (run_queue) { |
1048 | if (!nr_requests_pending || | |
1049 | (nr_requests_pending >= md->queue->nr_congestion_on)) | |
1050 | blk_run_queue_async(md->queue); | |
1051 | } | |
cec47e3d KU |
1052 | |
1053 | /* | |
1054 | * dm_put() must be at the end of this function. See the comment above | |
1055 | */ | |
1056 | dm_put(md); | |
1057 | } | |
1058 | ||
a77e28c7 KU |
1059 | static void free_rq_clone(struct request *clone) |
1060 | { | |
1061 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1062 | ||
1063 | blk_rq_unprep_clone(clone); | |
e5863d9a MS |
1064 | if (clone->q && clone->q->mq_ops) |
1065 | tio->ti->type->release_clone_rq(clone); | |
1066 | else | |
1067 | free_clone_request(tio->md, clone); | |
a77e28c7 KU |
1068 | free_rq_tio(tio); |
1069 | } | |
1070 | ||
980691e5 KU |
1071 | /* |
1072 | * Complete the clone and the original request. | |
466d89a6 KB |
1073 | * Must be called without clone's queue lock held, |
1074 | * see end_clone_request() for more details. | |
980691e5 KU |
1075 | */ |
1076 | static void dm_end_request(struct request *clone, int error) | |
1077 | { | |
1078 | int rw = rq_data_dir(clone); | |
1079 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1080 | struct mapped_device *md = tio->md; | |
1081 | struct request *rq = tio->orig; | |
1082 | ||
29e4013d | 1083 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
980691e5 KU |
1084 | rq->errors = clone->errors; |
1085 | rq->resid_len = clone->resid_len; | |
1086 | ||
1087 | if (rq->sense) | |
1088 | /* | |
1089 | * We are using the sense buffer of the original | |
1090 | * request. | |
1091 | * So setting the length of the sense data is enough. | |
1092 | */ | |
1093 | rq->sense_len = clone->sense_len; | |
1094 | } | |
1095 | ||
1096 | free_rq_clone(clone); | |
29e4013d TH |
1097 | blk_end_request_all(rq, error); |
1098 | rq_completed(md, rw, true); | |
980691e5 KU |
1099 | } |
1100 | ||
cec47e3d KU |
1101 | static void dm_unprep_request(struct request *rq) |
1102 | { | |
466d89a6 KB |
1103 | struct dm_rq_target_io *tio = rq->special; |
1104 | struct request *clone = tio->clone; | |
cec47e3d KU |
1105 | |
1106 | rq->special = NULL; | |
1107 | rq->cmd_flags &= ~REQ_DONTPREP; | |
1108 | ||
e5863d9a MS |
1109 | if (clone) |
1110 | free_rq_clone(clone); | |
cec47e3d KU |
1111 | } |
1112 | ||
1113 | /* | |
1114 | * Requeue the original request of a clone. | |
1115 | */ | |
466d89a6 KB |
1116 | static void dm_requeue_unmapped_original_request(struct mapped_device *md, |
1117 | struct request *rq) | |
cec47e3d | 1118 | { |
466d89a6 | 1119 | int rw = rq_data_dir(rq); |
cec47e3d KU |
1120 | struct request_queue *q = rq->q; |
1121 | unsigned long flags; | |
1122 | ||
1123 | dm_unprep_request(rq); | |
1124 | ||
1125 | spin_lock_irqsave(q->queue_lock, flags); | |
cec47e3d KU |
1126 | blk_requeue_request(q, rq); |
1127 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1128 | ||
466d89a6 KB |
1129 | rq_completed(md, rw, false); |
1130 | } | |
1131 | ||
1132 | static void dm_requeue_unmapped_request(struct request *clone) | |
1133 | { | |
1134 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1135 | ||
1136 | dm_requeue_unmapped_original_request(tio->md, tio->orig); | |
cec47e3d | 1137 | } |
cec47e3d KU |
1138 | |
1139 | static void __stop_queue(struct request_queue *q) | |
1140 | { | |
1141 | blk_stop_queue(q); | |
1142 | } | |
1143 | ||
1144 | static void stop_queue(struct request_queue *q) | |
1145 | { | |
1146 | unsigned long flags; | |
1147 | ||
1148 | spin_lock_irqsave(q->queue_lock, flags); | |
1149 | __stop_queue(q); | |
1150 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1151 | } | |
1152 | ||
1153 | static void __start_queue(struct request_queue *q) | |
1154 | { | |
1155 | if (blk_queue_stopped(q)) | |
1156 | blk_start_queue(q); | |
1157 | } | |
1158 | ||
1159 | static void start_queue(struct request_queue *q) | |
1160 | { | |
1161 | unsigned long flags; | |
1162 | ||
1163 | spin_lock_irqsave(q->queue_lock, flags); | |
1164 | __start_queue(q); | |
1165 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1166 | } | |
1167 | ||
11a68244 | 1168 | static void dm_done(struct request *clone, int error, bool mapped) |
cec47e3d | 1169 | { |
11a68244 | 1170 | int r = error; |
cec47e3d | 1171 | struct dm_rq_target_io *tio = clone->end_io_data; |
ba1cbad9 | 1172 | dm_request_endio_fn rq_end_io = NULL; |
cec47e3d | 1173 | |
ba1cbad9 MS |
1174 | if (tio->ti) { |
1175 | rq_end_io = tio->ti->type->rq_end_io; | |
1176 | ||
1177 | if (mapped && rq_end_io) | |
1178 | r = rq_end_io(tio->ti, clone, error, &tio->info); | |
1179 | } | |
cec47e3d | 1180 | |
7eee4ae2 MS |
1181 | if (unlikely(r == -EREMOTEIO && (clone->cmd_flags & REQ_WRITE_SAME) && |
1182 | !clone->q->limits.max_write_same_sectors)) | |
1183 | disable_write_same(tio->md); | |
1184 | ||
11a68244 | 1185 | if (r <= 0) |
cec47e3d | 1186 | /* The target wants to complete the I/O */ |
11a68244 KU |
1187 | dm_end_request(clone, r); |
1188 | else if (r == DM_ENDIO_INCOMPLETE) | |
cec47e3d KU |
1189 | /* The target will handle the I/O */ |
1190 | return; | |
11a68244 | 1191 | else if (r == DM_ENDIO_REQUEUE) |
cec47e3d KU |
1192 | /* The target wants to requeue the I/O */ |
1193 | dm_requeue_unmapped_request(clone); | |
1194 | else { | |
11a68244 | 1195 | DMWARN("unimplemented target endio return value: %d", r); |
cec47e3d KU |
1196 | BUG(); |
1197 | } | |
1198 | } | |
1199 | ||
11a68244 KU |
1200 | /* |
1201 | * Request completion handler for request-based dm | |
1202 | */ | |
1203 | static void dm_softirq_done(struct request *rq) | |
1204 | { | |
1205 | bool mapped = true; | |
466d89a6 KB |
1206 | struct dm_rq_target_io *tio = rq->special; |
1207 | struct request *clone = tio->clone; | |
11a68244 | 1208 | |
e5863d9a MS |
1209 | if (!clone) { |
1210 | blk_end_request_all(rq, tio->error); | |
1211 | rq_completed(tio->md, rq_data_dir(rq), false); | |
1212 | free_rq_tio(tio); | |
1213 | return; | |
1214 | } | |
11a68244 KU |
1215 | |
1216 | if (rq->cmd_flags & REQ_FAILED) | |
1217 | mapped = false; | |
1218 | ||
1219 | dm_done(clone, tio->error, mapped); | |
1220 | } | |
1221 | ||
cec47e3d KU |
1222 | /* |
1223 | * Complete the clone and the original request with the error status | |
1224 | * through softirq context. | |
1225 | */ | |
466d89a6 | 1226 | static void dm_complete_request(struct request *rq, int error) |
cec47e3d | 1227 | { |
466d89a6 | 1228 | struct dm_rq_target_io *tio = rq->special; |
cec47e3d KU |
1229 | |
1230 | tio->error = error; | |
cec47e3d KU |
1231 | blk_complete_request(rq); |
1232 | } | |
1233 | ||
1234 | /* | |
1235 | * Complete the not-mapped clone and the original request with the error status | |
1236 | * through softirq context. | |
1237 | * Target's rq_end_io() function isn't called. | |
e5863d9a | 1238 | * This may be used when the target's map_rq() or clone_and_map_rq() functions fail. |
cec47e3d | 1239 | */ |
466d89a6 | 1240 | static void dm_kill_unmapped_request(struct request *rq, int error) |
cec47e3d | 1241 | { |
cec47e3d | 1242 | rq->cmd_flags |= REQ_FAILED; |
466d89a6 | 1243 | dm_complete_request(rq, error); |
cec47e3d | 1244 | } |
cec47e3d KU |
1245 | |
1246 | /* | |
466d89a6 | 1247 | * Called with the clone's queue lock held |
cec47e3d KU |
1248 | */ |
1249 | static void end_clone_request(struct request *clone, int error) | |
1250 | { | |
466d89a6 KB |
1251 | struct dm_rq_target_io *tio = clone->end_io_data; |
1252 | ||
e5863d9a MS |
1253 | if (!clone->q->mq_ops) { |
1254 | /* | |
1255 | * For just cleaning up the information of the queue in which | |
1256 | * the clone was dispatched. | |
1257 | * The clone is *NOT* freed actually here because it is alloced | |
1258 | * from dm own mempool (REQ_ALLOCED isn't set). | |
1259 | */ | |
1260 | __blk_put_request(clone->q, clone); | |
1261 | } | |
cec47e3d KU |
1262 | |
1263 | /* | |
1264 | * Actual request completion is done in a softirq context which doesn't | |
466d89a6 | 1265 | * hold the clone's queue lock. Otherwise, deadlock could occur because: |
cec47e3d KU |
1266 | * - another request may be submitted by the upper level driver |
1267 | * of the stacking during the completion | |
1268 | * - the submission which requires queue lock may be done | |
466d89a6 | 1269 | * against this clone's queue |
cec47e3d | 1270 | */ |
466d89a6 | 1271 | dm_complete_request(tio->orig, error); |
cec47e3d KU |
1272 | } |
1273 | ||
56a67df7 MS |
1274 | /* |
1275 | * Return maximum size of I/O possible at the supplied sector up to the current | |
1276 | * target boundary. | |
1277 | */ | |
1278 | static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti) | |
1279 | { | |
1280 | sector_t target_offset = dm_target_offset(ti, sector); | |
1281 | ||
1282 | return ti->len - target_offset; | |
1283 | } | |
1284 | ||
1285 | static sector_t max_io_len(sector_t sector, struct dm_target *ti) | |
1da177e4 | 1286 | { |
56a67df7 | 1287 | sector_t len = max_io_len_target_boundary(sector, ti); |
542f9038 | 1288 | sector_t offset, max_len; |
1da177e4 LT |
1289 | |
1290 | /* | |
542f9038 | 1291 | * Does the target need to split even further? |
1da177e4 | 1292 | */ |
542f9038 MS |
1293 | if (ti->max_io_len) { |
1294 | offset = dm_target_offset(ti, sector); | |
1295 | if (unlikely(ti->max_io_len & (ti->max_io_len - 1))) | |
1296 | max_len = sector_div(offset, ti->max_io_len); | |
1297 | else | |
1298 | max_len = offset & (ti->max_io_len - 1); | |
1299 | max_len = ti->max_io_len - max_len; | |
1300 | ||
1301 | if (len > max_len) | |
1302 | len = max_len; | |
1da177e4 LT |
1303 | } |
1304 | ||
1305 | return len; | |
1306 | } | |
1307 | ||
542f9038 MS |
1308 | int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) |
1309 | { | |
1310 | if (len > UINT_MAX) { | |
1311 | DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)", | |
1312 | (unsigned long long)len, UINT_MAX); | |
1313 | ti->error = "Maximum size of target IO is too large"; | |
1314 | return -EINVAL; | |
1315 | } | |
1316 | ||
1317 | ti->max_io_len = (uint32_t) len; | |
1318 | ||
1319 | return 0; | |
1320 | } | |
1321 | EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); | |
1322 | ||
1dd40c3e MP |
1323 | /* |
1324 | * A target may call dm_accept_partial_bio only from the map routine. It is | |
1325 | * allowed for all bio types except REQ_FLUSH. | |
1326 | * | |
1327 | * dm_accept_partial_bio informs the dm that the target only wants to process | |
1328 | * additional n_sectors sectors of the bio and the rest of the data should be | |
1329 | * sent in a next bio. | |
1330 | * | |
1331 | * A diagram that explains the arithmetics: | |
1332 | * +--------------------+---------------+-------+ | |
1333 | * | 1 | 2 | 3 | | |
1334 | * +--------------------+---------------+-------+ | |
1335 | * | |
1336 | * <-------------- *tio->len_ptr ---------------> | |
1337 | * <------- bi_size -------> | |
1338 | * <-- n_sectors --> | |
1339 | * | |
1340 | * Region 1 was already iterated over with bio_advance or similar function. | |
1341 | * (it may be empty if the target doesn't use bio_advance) | |
1342 | * Region 2 is the remaining bio size that the target wants to process. | |
1343 | * (it may be empty if region 1 is non-empty, although there is no reason | |
1344 | * to make it empty) | |
1345 | * The target requires that region 3 is to be sent in the next bio. | |
1346 | * | |
1347 | * If the target wants to receive multiple copies of the bio (via num_*bios, etc), | |
1348 | * the partially processed part (the sum of regions 1+2) must be the same for all | |
1349 | * copies of the bio. | |
1350 | */ | |
1351 | void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) | |
1352 | { | |
1353 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); | |
1354 | unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; | |
1355 | BUG_ON(bio->bi_rw & REQ_FLUSH); | |
1356 | BUG_ON(bi_size > *tio->len_ptr); | |
1357 | BUG_ON(n_sectors > bi_size); | |
1358 | *tio->len_ptr -= bi_size - n_sectors; | |
1359 | bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT; | |
1360 | } | |
1361 | EXPORT_SYMBOL_GPL(dm_accept_partial_bio); | |
1362 | ||
bd2a49b8 | 1363 | static void __map_bio(struct dm_target_io *tio) |
1da177e4 LT |
1364 | { |
1365 | int r; | |
2056a782 | 1366 | sector_t sector; |
9faf400f | 1367 | struct mapped_device *md; |
dba14160 | 1368 | struct bio *clone = &tio->clone; |
bd2a49b8 | 1369 | struct dm_target *ti = tio->ti; |
1da177e4 | 1370 | |
1da177e4 | 1371 | clone->bi_end_io = clone_endio; |
1da177e4 LT |
1372 | |
1373 | /* | |
1374 | * Map the clone. If r == 0 we don't need to do | |
1375 | * anything, the target has assumed ownership of | |
1376 | * this io. | |
1377 | */ | |
1378 | atomic_inc(&tio->io->io_count); | |
4f024f37 | 1379 | sector = clone->bi_iter.bi_sector; |
7de3ee57 | 1380 | r = ti->type->map(ti, clone); |
45cbcd79 | 1381 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 1382 | /* the bio has been remapped so dispatch it */ |
2056a782 | 1383 | |
d07335e5 MS |
1384 | trace_block_bio_remap(bdev_get_queue(clone->bi_bdev), clone, |
1385 | tio->io->bio->bi_bdev->bd_dev, sector); | |
2056a782 | 1386 | |
1da177e4 | 1387 | generic_make_request(clone); |
2e93ccc1 KU |
1388 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
1389 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
1390 | md = tio->io->md; |
1391 | dec_pending(tio->io, r); | |
9faf400f | 1392 | free_tio(md, tio); |
45cbcd79 KU |
1393 | } else if (r) { |
1394 | DMWARN("unimplemented target map return value: %d", r); | |
1395 | BUG(); | |
1da177e4 LT |
1396 | } |
1397 | } | |
1398 | ||
1399 | struct clone_info { | |
1400 | struct mapped_device *md; | |
1401 | struct dm_table *map; | |
1402 | struct bio *bio; | |
1403 | struct dm_io *io; | |
1404 | sector_t sector; | |
e0d6609a | 1405 | unsigned sector_count; |
1da177e4 LT |
1406 | }; |
1407 | ||
e0d6609a | 1408 | static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) |
bd2a49b8 | 1409 | { |
4f024f37 KO |
1410 | bio->bi_iter.bi_sector = sector; |
1411 | bio->bi_iter.bi_size = to_bytes(len); | |
1da177e4 LT |
1412 | } |
1413 | ||
1414 | /* | |
1415 | * Creates a bio that consists of range of complete bvecs. | |
1416 | */ | |
dba14160 | 1417 | static void clone_bio(struct dm_target_io *tio, struct bio *bio, |
1c3b13e6 | 1418 | sector_t sector, unsigned len) |
1da177e4 | 1419 | { |
dba14160 | 1420 | struct bio *clone = &tio->clone; |
1da177e4 | 1421 | |
1c3b13e6 KO |
1422 | __bio_clone_fast(clone, bio); |
1423 | ||
1424 | if (bio_integrity(bio)) | |
1425 | bio_integrity_clone(clone, bio, GFP_NOIO); | |
bd2a49b8 | 1426 | |
1c3b13e6 KO |
1427 | bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); |
1428 | clone->bi_iter.bi_size = to_bytes(len); | |
1429 | ||
1430 | if (bio_integrity(bio)) | |
1431 | bio_integrity_trim(clone, 0, len); | |
1da177e4 LT |
1432 | } |
1433 | ||
9015df24 | 1434 | static struct dm_target_io *alloc_tio(struct clone_info *ci, |
99778273 | 1435 | struct dm_target *ti, |
55a62eef | 1436 | unsigned target_bio_nr) |
f9ab94ce | 1437 | { |
dba14160 MP |
1438 | struct dm_target_io *tio; |
1439 | struct bio *clone; | |
1440 | ||
99778273 | 1441 | clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs); |
dba14160 | 1442 | tio = container_of(clone, struct dm_target_io, clone); |
f9ab94ce MP |
1443 | |
1444 | tio->io = ci->io; | |
1445 | tio->ti = ti; | |
55a62eef | 1446 | tio->target_bio_nr = target_bio_nr; |
9015df24 AK |
1447 | |
1448 | return tio; | |
1449 | } | |
1450 | ||
14fe594d AK |
1451 | static void __clone_and_map_simple_bio(struct clone_info *ci, |
1452 | struct dm_target *ti, | |
1dd40c3e | 1453 | unsigned target_bio_nr, unsigned *len) |
9015df24 | 1454 | { |
99778273 | 1455 | struct dm_target_io *tio = alloc_tio(ci, ti, target_bio_nr); |
dba14160 | 1456 | struct bio *clone = &tio->clone; |
9015df24 | 1457 | |
1dd40c3e MP |
1458 | tio->len_ptr = len; |
1459 | ||
99778273 | 1460 | __bio_clone_fast(clone, ci->bio); |
bd2a49b8 | 1461 | if (len) |
1dd40c3e | 1462 | bio_setup_sector(clone, ci->sector, *len); |
f9ab94ce | 1463 | |
bd2a49b8 | 1464 | __map_bio(tio); |
f9ab94ce MP |
1465 | } |
1466 | ||
14fe594d | 1467 | static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, |
1dd40c3e | 1468 | unsigned num_bios, unsigned *len) |
06a426ce | 1469 | { |
55a62eef | 1470 | unsigned target_bio_nr; |
06a426ce | 1471 | |
55a62eef | 1472 | for (target_bio_nr = 0; target_bio_nr < num_bios; target_bio_nr++) |
14fe594d | 1473 | __clone_and_map_simple_bio(ci, ti, target_bio_nr, len); |
06a426ce MS |
1474 | } |
1475 | ||
14fe594d | 1476 | static int __send_empty_flush(struct clone_info *ci) |
f9ab94ce | 1477 | { |
06a426ce | 1478 | unsigned target_nr = 0; |
f9ab94ce MP |
1479 | struct dm_target *ti; |
1480 | ||
b372d360 | 1481 | BUG_ON(bio_has_data(ci->bio)); |
f9ab94ce | 1482 | while ((ti = dm_table_get_target(ci->map, target_nr++))) |
1dd40c3e | 1483 | __send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL); |
f9ab94ce | 1484 | |
f9ab94ce MP |
1485 | return 0; |
1486 | } | |
1487 | ||
e4c93811 | 1488 | static void __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, |
1dd40c3e | 1489 | sector_t sector, unsigned *len) |
5ae89a87 | 1490 | { |
dba14160 | 1491 | struct bio *bio = ci->bio; |
5ae89a87 | 1492 | struct dm_target_io *tio; |
b0d8ed4d AK |
1493 | unsigned target_bio_nr; |
1494 | unsigned num_target_bios = 1; | |
5ae89a87 | 1495 | |
b0d8ed4d AK |
1496 | /* |
1497 | * Does the target want to receive duplicate copies of the bio? | |
1498 | */ | |
1499 | if (bio_data_dir(bio) == WRITE && ti->num_write_bios) | |
1500 | num_target_bios = ti->num_write_bios(ti, bio); | |
e4c93811 | 1501 | |
b0d8ed4d | 1502 | for (target_bio_nr = 0; target_bio_nr < num_target_bios; target_bio_nr++) { |
99778273 | 1503 | tio = alloc_tio(ci, ti, target_bio_nr); |
1dd40c3e MP |
1504 | tio->len_ptr = len; |
1505 | clone_bio(tio, bio, sector, *len); | |
b0d8ed4d AK |
1506 | __map_bio(tio); |
1507 | } | |
5ae89a87 MS |
1508 | } |
1509 | ||
55a62eef | 1510 | typedef unsigned (*get_num_bios_fn)(struct dm_target *ti); |
23508a96 | 1511 | |
55a62eef | 1512 | static unsigned get_num_discard_bios(struct dm_target *ti) |
23508a96 | 1513 | { |
55a62eef | 1514 | return ti->num_discard_bios; |
23508a96 MS |
1515 | } |
1516 | ||
55a62eef | 1517 | static unsigned get_num_write_same_bios(struct dm_target *ti) |
23508a96 | 1518 | { |
55a62eef | 1519 | return ti->num_write_same_bios; |
23508a96 MS |
1520 | } |
1521 | ||
1522 | typedef bool (*is_split_required_fn)(struct dm_target *ti); | |
1523 | ||
1524 | static bool is_split_required_for_discard(struct dm_target *ti) | |
1525 | { | |
55a62eef | 1526 | return ti->split_discard_bios; |
23508a96 MS |
1527 | } |
1528 | ||
14fe594d AK |
1529 | static int __send_changing_extent_only(struct clone_info *ci, |
1530 | get_num_bios_fn get_num_bios, | |
1531 | is_split_required_fn is_split_required) | |
5ae89a87 MS |
1532 | { |
1533 | struct dm_target *ti; | |
e0d6609a | 1534 | unsigned len; |
55a62eef | 1535 | unsigned num_bios; |
5ae89a87 | 1536 | |
a79245b3 MS |
1537 | do { |
1538 | ti = dm_table_find_target(ci->map, ci->sector); | |
1539 | if (!dm_target_is_valid(ti)) | |
1540 | return -EIO; | |
5ae89a87 | 1541 | |
5ae89a87 | 1542 | /* |
23508a96 MS |
1543 | * Even though the device advertised support for this type of |
1544 | * request, that does not mean every target supports it, and | |
936688d7 | 1545 | * reconfiguration might also have changed that since the |
a79245b3 | 1546 | * check was performed. |
5ae89a87 | 1547 | */ |
55a62eef AK |
1548 | num_bios = get_num_bios ? get_num_bios(ti) : 0; |
1549 | if (!num_bios) | |
a79245b3 | 1550 | return -EOPNOTSUPP; |
5ae89a87 | 1551 | |
23508a96 | 1552 | if (is_split_required && !is_split_required(ti)) |
e0d6609a | 1553 | len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); |
7acf0277 | 1554 | else |
e0d6609a | 1555 | len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti)); |
06a426ce | 1556 | |
1dd40c3e | 1557 | __send_duplicate_bios(ci, ti, num_bios, &len); |
a79245b3 MS |
1558 | |
1559 | ci->sector += len; | |
1560 | } while (ci->sector_count -= len); | |
5ae89a87 MS |
1561 | |
1562 | return 0; | |
1563 | } | |
1564 | ||
14fe594d | 1565 | static int __send_discard(struct clone_info *ci) |
23508a96 | 1566 | { |
14fe594d AK |
1567 | return __send_changing_extent_only(ci, get_num_discard_bios, |
1568 | is_split_required_for_discard); | |
23508a96 MS |
1569 | } |
1570 | ||
14fe594d | 1571 | static int __send_write_same(struct clone_info *ci) |
23508a96 | 1572 | { |
14fe594d | 1573 | return __send_changing_extent_only(ci, get_num_write_same_bios, NULL); |
23508a96 MS |
1574 | } |
1575 | ||
e4c93811 AK |
1576 | /* |
1577 | * Select the correct strategy for processing a non-flush bio. | |
1578 | */ | |
14fe594d | 1579 | static int __split_and_process_non_flush(struct clone_info *ci) |
1da177e4 | 1580 | { |
dba14160 | 1581 | struct bio *bio = ci->bio; |
512875bd | 1582 | struct dm_target *ti; |
1c3b13e6 | 1583 | unsigned len; |
1da177e4 | 1584 | |
5ae89a87 | 1585 | if (unlikely(bio->bi_rw & REQ_DISCARD)) |
14fe594d | 1586 | return __send_discard(ci); |
23508a96 | 1587 | else if (unlikely(bio->bi_rw & REQ_WRITE_SAME)) |
14fe594d | 1588 | return __send_write_same(ci); |
5ae89a87 | 1589 | |
512875bd JN |
1590 | ti = dm_table_find_target(ci->map, ci->sector); |
1591 | if (!dm_target_is_valid(ti)) | |
1592 | return -EIO; | |
1593 | ||
1c3b13e6 | 1594 | len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count); |
1da177e4 | 1595 | |
1dd40c3e | 1596 | __clone_and_map_data_bio(ci, ti, ci->sector, &len); |
1da177e4 | 1597 | |
1c3b13e6 KO |
1598 | ci->sector += len; |
1599 | ci->sector_count -= len; | |
1da177e4 | 1600 | |
1c3b13e6 | 1601 | return 0; |
1da177e4 LT |
1602 | } |
1603 | ||
1604 | /* | |
14fe594d | 1605 | * Entry point to split a bio into clones and submit them to the targets. |
1da177e4 | 1606 | */ |
83d5e5b0 MP |
1607 | static void __split_and_process_bio(struct mapped_device *md, |
1608 | struct dm_table *map, struct bio *bio) | |
1da177e4 LT |
1609 | { |
1610 | struct clone_info ci; | |
512875bd | 1611 | int error = 0; |
1da177e4 | 1612 | |
83d5e5b0 | 1613 | if (unlikely(!map)) { |
6a8736d1 | 1614 | bio_io_error(bio); |
f0b9a450 MP |
1615 | return; |
1616 | } | |
692d0eb9 | 1617 | |
83d5e5b0 | 1618 | ci.map = map; |
1da177e4 | 1619 | ci.md = md; |
1da177e4 LT |
1620 | ci.io = alloc_io(md); |
1621 | ci.io->error = 0; | |
1622 | atomic_set(&ci.io->io_count, 1); | |
1623 | ci.io->bio = bio; | |
1624 | ci.io->md = md; | |
f88fb981 | 1625 | spin_lock_init(&ci.io->endio_lock); |
4f024f37 | 1626 | ci.sector = bio->bi_iter.bi_sector; |
1da177e4 | 1627 | |
3eaf840e | 1628 | start_io_acct(ci.io); |
bd2a49b8 | 1629 | |
b372d360 MS |
1630 | if (bio->bi_rw & REQ_FLUSH) { |
1631 | ci.bio = &ci.md->flush_bio; | |
1632 | ci.sector_count = 0; | |
14fe594d | 1633 | error = __send_empty_flush(&ci); |
b372d360 MS |
1634 | /* dec_pending submits any data associated with flush */ |
1635 | } else { | |
6a8736d1 | 1636 | ci.bio = bio; |
d87f4c14 | 1637 | ci.sector_count = bio_sectors(bio); |
b372d360 | 1638 | while (ci.sector_count && !error) |
14fe594d | 1639 | error = __split_and_process_non_flush(&ci); |
d87f4c14 | 1640 | } |
1da177e4 LT |
1641 | |
1642 | /* drop the extra reference count */ | |
512875bd | 1643 | dec_pending(ci.io, error); |
1da177e4 LT |
1644 | } |
1645 | /*----------------------------------------------------------------- | |
1646 | * CRUD END | |
1647 | *---------------------------------------------------------------*/ | |
1648 | ||
f6fccb12 MB |
1649 | static int dm_merge_bvec(struct request_queue *q, |
1650 | struct bvec_merge_data *bvm, | |
1651 | struct bio_vec *biovec) | |
1652 | { | |
1653 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 | 1654 | struct dm_table *map = dm_get_live_table_fast(md); |
f6fccb12 MB |
1655 | struct dm_target *ti; |
1656 | sector_t max_sectors; | |
5037108a | 1657 | int max_size = 0; |
f6fccb12 MB |
1658 | |
1659 | if (unlikely(!map)) | |
5037108a | 1660 | goto out; |
f6fccb12 MB |
1661 | |
1662 | ti = dm_table_find_target(map, bvm->bi_sector); | |
b01cd5ac | 1663 | if (!dm_target_is_valid(ti)) |
83d5e5b0 | 1664 | goto out; |
f6fccb12 MB |
1665 | |
1666 | /* | |
1667 | * Find maximum amount of I/O that won't need splitting | |
1668 | */ | |
56a67df7 | 1669 | max_sectors = min(max_io_len(bvm->bi_sector, ti), |
148e51ba | 1670 | (sector_t) queue_max_sectors(q)); |
f6fccb12 | 1671 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; |
148e51ba | 1672 | if (unlikely(max_size < 0)) /* this shouldn't _ever_ happen */ |
f6fccb12 MB |
1673 | max_size = 0; |
1674 | ||
1675 | /* | |
1676 | * merge_bvec_fn() returns number of bytes | |
1677 | * it can accept at this offset | |
1678 | * max is precomputed maximal io size | |
1679 | */ | |
1680 | if (max_size && ti->type->merge) | |
1681 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
8cbeb67a MP |
1682 | /* |
1683 | * If the target doesn't support merge method and some of the devices | |
148e51ba MS |
1684 | * provided their merge_bvec method (we know this by looking for the |
1685 | * max_hw_sectors that dm_set_device_limits may set), then we can't | |
1686 | * allow bios with multiple vector entries. So always set max_size | |
1687 | * to 0, and the code below allows just one page. | |
8cbeb67a MP |
1688 | */ |
1689 | else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9) | |
8cbeb67a | 1690 | max_size = 0; |
f6fccb12 | 1691 | |
5037108a | 1692 | out: |
83d5e5b0 | 1693 | dm_put_live_table_fast(md); |
f6fccb12 MB |
1694 | /* |
1695 | * Always allow an entire first page | |
1696 | */ | |
1697 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
1698 | max_size = biovec->bv_len; | |
1699 | ||
f6fccb12 MB |
1700 | return max_size; |
1701 | } | |
1702 | ||
1da177e4 LT |
1703 | /* |
1704 | * The request function that just remaps the bio built up by | |
1705 | * dm_merge_bvec. | |
1706 | */ | |
ff36ab34 | 1707 | static void dm_make_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 1708 | { |
12f03a49 | 1709 | int rw = bio_data_dir(bio); |
1da177e4 | 1710 | struct mapped_device *md = q->queuedata; |
83d5e5b0 MP |
1711 | int srcu_idx; |
1712 | struct dm_table *map; | |
1da177e4 | 1713 | |
83d5e5b0 | 1714 | map = dm_get_live_table(md, &srcu_idx); |
1da177e4 | 1715 | |
18c0b223 | 1716 | generic_start_io_acct(rw, bio_sectors(bio), &dm_disk(md)->part0); |
12f03a49 | 1717 | |
6a8736d1 TH |
1718 | /* if we're suspended, we have to queue this io for later */ |
1719 | if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { | |
83d5e5b0 | 1720 | dm_put_live_table(md, srcu_idx); |
1da177e4 | 1721 | |
6a8736d1 TH |
1722 | if (bio_rw(bio) != READA) |
1723 | queue_io(md, bio); | |
1724 | else | |
54d9a1b4 | 1725 | bio_io_error(bio); |
5a7bbad2 | 1726 | return; |
1da177e4 LT |
1727 | } |
1728 | ||
83d5e5b0 MP |
1729 | __split_and_process_bio(md, map, bio); |
1730 | dm_put_live_table(md, srcu_idx); | |
5a7bbad2 | 1731 | return; |
cec47e3d KU |
1732 | } |
1733 | ||
fd2ed4d2 | 1734 | int dm_request_based(struct mapped_device *md) |
cec47e3d KU |
1735 | { |
1736 | return blk_queue_stackable(md->queue); | |
1737 | } | |
1738 | ||
466d89a6 | 1739 | static void dm_dispatch_clone_request(struct request *clone, struct request *rq) |
cec47e3d KU |
1740 | { |
1741 | int r; | |
1742 | ||
466d89a6 KB |
1743 | if (blk_queue_io_stat(clone->q)) |
1744 | clone->cmd_flags |= REQ_IO_STAT; | |
cec47e3d | 1745 | |
466d89a6 KB |
1746 | clone->start_time = jiffies; |
1747 | r = blk_insert_cloned_request(clone->q, clone); | |
cec47e3d | 1748 | if (r) |
466d89a6 | 1749 | /* must complete clone in terms of original request */ |
cec47e3d KU |
1750 | dm_complete_request(rq, r); |
1751 | } | |
cec47e3d | 1752 | |
cec47e3d KU |
1753 | static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig, |
1754 | void *data) | |
1755 | { | |
1756 | struct dm_rq_target_io *tio = data; | |
94818742 KO |
1757 | struct dm_rq_clone_bio_info *info = |
1758 | container_of(bio, struct dm_rq_clone_bio_info, clone); | |
cec47e3d KU |
1759 | |
1760 | info->orig = bio_orig; | |
1761 | info->tio = tio; | |
1762 | bio->bi_end_io = end_clone_bio; | |
cec47e3d KU |
1763 | |
1764 | return 0; | |
1765 | } | |
1766 | ||
1767 | static int setup_clone(struct request *clone, struct request *rq, | |
1ae49ea2 | 1768 | struct dm_rq_target_io *tio, gfp_t gfp_mask) |
cec47e3d | 1769 | { |
d0bcb878 | 1770 | int r; |
cec47e3d | 1771 | |
1ae49ea2 | 1772 | r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask, |
29e4013d TH |
1773 | dm_rq_bio_constructor, tio); |
1774 | if (r) | |
1775 | return r; | |
cec47e3d | 1776 | |
29e4013d TH |
1777 | clone->cmd = rq->cmd; |
1778 | clone->cmd_len = rq->cmd_len; | |
1779 | clone->sense = rq->sense; | |
cec47e3d KU |
1780 | clone->end_io = end_clone_request; |
1781 | clone->end_io_data = tio; | |
1782 | ||
1ae49ea2 MS |
1783 | tio->clone = clone; |
1784 | ||
cec47e3d KU |
1785 | return 0; |
1786 | } | |
1787 | ||
6facdaff | 1788 | static struct request *clone_rq(struct request *rq, struct mapped_device *md, |
466d89a6 | 1789 | struct dm_rq_target_io *tio, gfp_t gfp_mask) |
1ae49ea2 MS |
1790 | { |
1791 | struct request *clone = alloc_clone_request(md, gfp_mask); | |
1792 | ||
1793 | if (!clone) | |
1794 | return NULL; | |
1795 | ||
1796 | blk_rq_init(NULL, clone); | |
1797 | if (setup_clone(clone, rq, tio, gfp_mask)) { | |
1798 | /* -ENOMEM */ | |
1799 | free_clone_request(md, clone); | |
1800 | return NULL; | |
1801 | } | |
1802 | ||
1803 | return clone; | |
1804 | } | |
1805 | ||
2eb6e1e3 KB |
1806 | static void map_tio_request(struct kthread_work *work); |
1807 | ||
466d89a6 KB |
1808 | static struct dm_rq_target_io *prep_tio(struct request *rq, |
1809 | struct mapped_device *md, gfp_t gfp_mask) | |
6facdaff | 1810 | { |
6facdaff | 1811 | struct dm_rq_target_io *tio; |
e5863d9a MS |
1812 | int srcu_idx; |
1813 | struct dm_table *table; | |
6facdaff KU |
1814 | |
1815 | tio = alloc_rq_tio(md, gfp_mask); | |
1816 | if (!tio) | |
1817 | return NULL; | |
1818 | ||
1819 | tio->md = md; | |
1820 | tio->ti = NULL; | |
1ae49ea2 | 1821 | tio->clone = NULL; |
6facdaff KU |
1822 | tio->orig = rq; |
1823 | tio->error = 0; | |
1824 | memset(&tio->info, 0, sizeof(tio->info)); | |
2eb6e1e3 | 1825 | init_kthread_work(&tio->work, map_tio_request); |
6facdaff | 1826 | |
e5863d9a MS |
1827 | table = dm_get_live_table(md, &srcu_idx); |
1828 | if (!dm_table_mq_request_based(table)) { | |
1829 | if (!clone_rq(rq, md, tio, gfp_mask)) { | |
1830 | dm_put_live_table(md, srcu_idx); | |
1831 | free_rq_tio(tio); | |
1832 | return NULL; | |
1833 | } | |
6facdaff | 1834 | } |
e5863d9a | 1835 | dm_put_live_table(md, srcu_idx); |
6facdaff | 1836 | |
466d89a6 | 1837 | return tio; |
6facdaff KU |
1838 | } |
1839 | ||
cec47e3d KU |
1840 | /* |
1841 | * Called with the queue lock held. | |
1842 | */ | |
1843 | static int dm_prep_fn(struct request_queue *q, struct request *rq) | |
1844 | { | |
1845 | struct mapped_device *md = q->queuedata; | |
466d89a6 | 1846 | struct dm_rq_target_io *tio; |
cec47e3d | 1847 | |
cec47e3d KU |
1848 | if (unlikely(rq->special)) { |
1849 | DMWARN("Already has something in rq->special."); | |
1850 | return BLKPREP_KILL; | |
1851 | } | |
1852 | ||
466d89a6 KB |
1853 | tio = prep_tio(rq, md, GFP_ATOMIC); |
1854 | if (!tio) | |
cec47e3d | 1855 | return BLKPREP_DEFER; |
cec47e3d | 1856 | |
466d89a6 | 1857 | rq->special = tio; |
cec47e3d KU |
1858 | rq->cmd_flags |= REQ_DONTPREP; |
1859 | ||
1860 | return BLKPREP_OK; | |
1861 | } | |
1862 | ||
9eef87da KU |
1863 | /* |
1864 | * Returns: | |
e5863d9a MS |
1865 | * 0 : the request has been processed |
1866 | * DM_MAPIO_REQUEUE : the original request needs to be requeued | |
1867 | * < 0 : the request was completed due to failure | |
9eef87da | 1868 | */ |
466d89a6 | 1869 | static int map_request(struct dm_target *ti, struct request *rq, |
9eef87da | 1870 | struct mapped_device *md) |
cec47e3d | 1871 | { |
e5863d9a | 1872 | int r; |
466d89a6 | 1873 | struct dm_rq_target_io *tio = rq->special; |
e5863d9a MS |
1874 | struct request *clone = NULL; |
1875 | ||
1876 | if (tio->clone) { | |
1877 | clone = tio->clone; | |
1878 | r = ti->type->map_rq(ti, clone, &tio->info); | |
1879 | } else { | |
1880 | r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone); | |
1881 | if (r < 0) { | |
1882 | /* The target wants to complete the I/O */ | |
1883 | dm_kill_unmapped_request(rq, r); | |
1884 | return r; | |
1885 | } | |
1886 | if (IS_ERR(clone)) | |
1887 | return DM_MAPIO_REQUEUE; | |
1888 | if (setup_clone(clone, rq, tio, GFP_KERNEL)) { | |
1889 | /* -ENOMEM */ | |
1890 | ti->type->release_clone_rq(clone); | |
1891 | return DM_MAPIO_REQUEUE; | |
1892 | } | |
1893 | } | |
cec47e3d | 1894 | |
cec47e3d KU |
1895 | switch (r) { |
1896 | case DM_MAPIO_SUBMITTED: | |
1897 | /* The target has taken the I/O to submit by itself later */ | |
1898 | break; | |
1899 | case DM_MAPIO_REMAPPED: | |
1900 | /* The target has remapped the I/O so dispatch it */ | |
6db4ccd6 | 1901 | trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)), |
466d89a6 KB |
1902 | blk_rq_pos(rq)); |
1903 | dm_dispatch_clone_request(clone, rq); | |
cec47e3d KU |
1904 | break; |
1905 | case DM_MAPIO_REQUEUE: | |
1906 | /* The target wants to requeue the I/O */ | |
1907 | dm_requeue_unmapped_request(clone); | |
1908 | break; | |
1909 | default: | |
1910 | if (r > 0) { | |
1911 | DMWARN("unimplemented target map return value: %d", r); | |
1912 | BUG(); | |
1913 | } | |
1914 | ||
1915 | /* The target wants to complete the I/O */ | |
466d89a6 | 1916 | dm_kill_unmapped_request(rq, r); |
e5863d9a | 1917 | return r; |
cec47e3d | 1918 | } |
9eef87da | 1919 | |
e5863d9a | 1920 | return 0; |
cec47e3d KU |
1921 | } |
1922 | ||
2eb6e1e3 | 1923 | static void map_tio_request(struct kthread_work *work) |
ba1cbad9 | 1924 | { |
2eb6e1e3 | 1925 | struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work); |
e5863d9a MS |
1926 | struct request *rq = tio->orig; |
1927 | struct mapped_device *md = tio->md; | |
ba1cbad9 | 1928 | |
e5863d9a MS |
1929 | if (map_request(tio->ti, rq, md) == DM_MAPIO_REQUEUE) |
1930 | dm_requeue_unmapped_original_request(md, rq); | |
2eb6e1e3 KB |
1931 | } |
1932 | ||
466d89a6 | 1933 | static void dm_start_request(struct mapped_device *md, struct request *orig) |
ba1cbad9 | 1934 | { |
ba1cbad9 | 1935 | blk_start_request(orig); |
466d89a6 | 1936 | atomic_inc(&md->pending[rq_data_dir(orig)]); |
ba1cbad9 | 1937 | |
de3ec86d MS |
1938 | md->last_rq_pos = rq_end_sector(orig); |
1939 | md->last_rq_rw = rq_data_dir(orig); | |
1940 | ||
ba1cbad9 MS |
1941 | /* |
1942 | * Hold the md reference here for the in-flight I/O. | |
1943 | * We can't rely on the reference count by device opener, | |
1944 | * because the device may be closed during the request completion | |
1945 | * when all bios are completed. | |
1946 | * See the comment in rq_completed() too. | |
1947 | */ | |
1948 | dm_get(md); | |
ba1cbad9 MS |
1949 | } |
1950 | ||
cec47e3d KU |
1951 | /* |
1952 | * q->request_fn for request-based dm. | |
1953 | * Called with the queue lock held. | |
1954 | */ | |
1955 | static void dm_request_fn(struct request_queue *q) | |
1956 | { | |
1957 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 MP |
1958 | int srcu_idx; |
1959 | struct dm_table *map = dm_get_live_table(md, &srcu_idx); | |
cec47e3d | 1960 | struct dm_target *ti; |
466d89a6 | 1961 | struct request *rq; |
2eb6e1e3 | 1962 | struct dm_rq_target_io *tio; |
29e4013d | 1963 | sector_t pos; |
cec47e3d KU |
1964 | |
1965 | /* | |
b4324fee KU |
1966 | * For suspend, check blk_queue_stopped() and increment |
1967 | * ->pending within a single queue_lock not to increment the | |
1968 | * number of in-flight I/Os after the queue is stopped in | |
1969 | * dm_suspend(). | |
cec47e3d | 1970 | */ |
7eaceacc | 1971 | while (!blk_queue_stopped(q)) { |
cec47e3d KU |
1972 | rq = blk_peek_request(q); |
1973 | if (!rq) | |
9d1deb83 | 1974 | goto out; |
cec47e3d | 1975 | |
29e4013d TH |
1976 | /* always use block 0 to find the target for flushes for now */ |
1977 | pos = 0; | |
1978 | if (!(rq->cmd_flags & REQ_FLUSH)) | |
1979 | pos = blk_rq_pos(rq); | |
1980 | ||
1981 | ti = dm_table_find_target(map, pos); | |
ba1cbad9 MS |
1982 | if (!dm_target_is_valid(ti)) { |
1983 | /* | |
466d89a6 | 1984 | * Must perform setup, that rq_completed() requires, |
ba1cbad9 MS |
1985 | * before calling dm_kill_unmapped_request |
1986 | */ | |
1987 | DMERR_LIMIT("request attempted access beyond the end of device"); | |
466d89a6 KB |
1988 | dm_start_request(md, rq); |
1989 | dm_kill_unmapped_request(rq, -EIO); | |
ba1cbad9 MS |
1990 | continue; |
1991 | } | |
d0bcb878 | 1992 | |
de3ec86d MS |
1993 | if (md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 && |
1994 | md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) | |
1995 | goto delay_and_out; | |
1996 | ||
cec47e3d | 1997 | if (ti->type->busy && ti->type->busy(ti)) |
7eaceacc | 1998 | goto delay_and_out; |
cec47e3d | 1999 | |
466d89a6 | 2000 | dm_start_request(md, rq); |
9eef87da | 2001 | |
2eb6e1e3 KB |
2002 | tio = rq->special; |
2003 | /* Establish tio->ti before queuing work (map_tio_request) */ | |
2004 | tio->ti = ti; | |
2005 | queue_kthread_work(&md->kworker, &tio->work); | |
052189a2 | 2006 | BUG_ON(!irqs_disabled()); |
cec47e3d KU |
2007 | } |
2008 | ||
2009 | goto out; | |
2010 | ||
7eaceacc | 2011 | delay_and_out: |
d548b34b | 2012 | blk_delay_queue(q, HZ / 100); |
cec47e3d | 2013 | out: |
83d5e5b0 | 2014 | dm_put_live_table(md, srcu_idx); |
cec47e3d KU |
2015 | } |
2016 | ||
1da177e4 LT |
2017 | static int dm_any_congested(void *congested_data, int bdi_bits) |
2018 | { | |
8a57dfc6 CS |
2019 | int r = bdi_bits; |
2020 | struct mapped_device *md = congested_data; | |
2021 | struct dm_table *map; | |
1da177e4 | 2022 | |
1eb787ec | 2023 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
83d5e5b0 | 2024 | map = dm_get_live_table_fast(md); |
8a57dfc6 | 2025 | if (map) { |
cec47e3d KU |
2026 | /* |
2027 | * Request-based dm cares about only own queue for | |
2028 | * the query about congestion status of request_queue | |
2029 | */ | |
2030 | if (dm_request_based(md)) | |
2031 | r = md->queue->backing_dev_info.state & | |
2032 | bdi_bits; | |
2033 | else | |
2034 | r = dm_table_any_congested(map, bdi_bits); | |
8a57dfc6 | 2035 | } |
83d5e5b0 | 2036 | dm_put_live_table_fast(md); |
8a57dfc6 CS |
2037 | } |
2038 | ||
1da177e4 LT |
2039 | return r; |
2040 | } | |
2041 | ||
2042 | /*----------------------------------------------------------------- | |
2043 | * An IDR is used to keep track of allocated minor numbers. | |
2044 | *---------------------------------------------------------------*/ | |
2b06cfff | 2045 | static void free_minor(int minor) |
1da177e4 | 2046 | { |
f32c10b0 | 2047 | spin_lock(&_minor_lock); |
1da177e4 | 2048 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 2049 | spin_unlock(&_minor_lock); |
1da177e4 LT |
2050 | } |
2051 | ||
2052 | /* | |
2053 | * See if the device with a specific minor # is free. | |
2054 | */ | |
cf13ab8e | 2055 | static int specific_minor(int minor) |
1da177e4 | 2056 | { |
c9d76be6 | 2057 | int r; |
1da177e4 LT |
2058 | |
2059 | if (minor >= (1 << MINORBITS)) | |
2060 | return -EINVAL; | |
2061 | ||
c9d76be6 | 2062 | idr_preload(GFP_KERNEL); |
f32c10b0 | 2063 | spin_lock(&_minor_lock); |
1da177e4 | 2064 | |
c9d76be6 | 2065 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT); |
1da177e4 | 2066 | |
f32c10b0 | 2067 | spin_unlock(&_minor_lock); |
c9d76be6 TH |
2068 | idr_preload_end(); |
2069 | if (r < 0) | |
2070 | return r == -ENOSPC ? -EBUSY : r; | |
2071 | return 0; | |
1da177e4 LT |
2072 | } |
2073 | ||
cf13ab8e | 2074 | static int next_free_minor(int *minor) |
1da177e4 | 2075 | { |
c9d76be6 | 2076 | int r; |
62f75c2f | 2077 | |
c9d76be6 | 2078 | idr_preload(GFP_KERNEL); |
f32c10b0 | 2079 | spin_lock(&_minor_lock); |
1da177e4 | 2080 | |
c9d76be6 | 2081 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT); |
1da177e4 | 2082 | |
f32c10b0 | 2083 | spin_unlock(&_minor_lock); |
c9d76be6 TH |
2084 | idr_preload_end(); |
2085 | if (r < 0) | |
2086 | return r; | |
2087 | *minor = r; | |
2088 | return 0; | |
1da177e4 LT |
2089 | } |
2090 | ||
83d5cde4 | 2091 | static const struct block_device_operations dm_blk_dops; |
1da177e4 | 2092 | |
53d5914f MP |
2093 | static void dm_wq_work(struct work_struct *work); |
2094 | ||
4a0b4ddf MS |
2095 | static void dm_init_md_queue(struct mapped_device *md) |
2096 | { | |
2097 | /* | |
2098 | * Request-based dm devices cannot be stacked on top of bio-based dm | |
2099 | * devices. The type of this dm device has not been decided yet. | |
2100 | * The type is decided at the first table loading time. | |
2101 | * To prevent problematic device stacking, clear the queue flag | |
2102 | * for request stacking support until then. | |
2103 | * | |
2104 | * This queue is new, so no concurrency on the queue_flags. | |
2105 | */ | |
2106 | queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue); | |
2107 | ||
2108 | md->queue->queuedata = md; | |
2109 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
2110 | md->queue->backing_dev_info.congested_data = md; | |
ff36ab34 | 2111 | |
4a0b4ddf | 2112 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); |
4a0b4ddf MS |
2113 | } |
2114 | ||
1da177e4 LT |
2115 | /* |
2116 | * Allocate and initialise a blank device with a given minor. | |
2117 | */ | |
2b06cfff | 2118 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
2119 | { |
2120 | int r; | |
cf13ab8e | 2121 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 2122 | void *old_md; |
1da177e4 LT |
2123 | |
2124 | if (!md) { | |
2125 | DMWARN("unable to allocate device, out of memory."); | |
2126 | return NULL; | |
2127 | } | |
2128 | ||
10da4f79 | 2129 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 2130 | goto bad_module_get; |
10da4f79 | 2131 | |
1da177e4 | 2132 | /* get a minor number for the dev */ |
2b06cfff | 2133 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 2134 | r = next_free_minor(&minor); |
2b06cfff | 2135 | else |
cf13ab8e | 2136 | r = specific_minor(minor); |
1da177e4 | 2137 | if (r < 0) |
6ed7ade8 | 2138 | goto bad_minor; |
1da177e4 | 2139 | |
83d5e5b0 MP |
2140 | r = init_srcu_struct(&md->io_barrier); |
2141 | if (r < 0) | |
2142 | goto bad_io_barrier; | |
2143 | ||
a5664dad | 2144 | md->type = DM_TYPE_NONE; |
e61290a4 | 2145 | mutex_init(&md->suspend_lock); |
a5664dad | 2146 | mutex_init(&md->type_lock); |
86f1152b | 2147 | mutex_init(&md->table_devices_lock); |
022c2611 | 2148 | spin_lock_init(&md->deferred_lock); |
1da177e4 | 2149 | atomic_set(&md->holders, 1); |
5c6bd75d | 2150 | atomic_set(&md->open_count, 0); |
1da177e4 | 2151 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
2152 | atomic_set(&md->uevent_seq, 0); |
2153 | INIT_LIST_HEAD(&md->uevent_list); | |
86f1152b | 2154 | INIT_LIST_HEAD(&md->table_devices); |
7a8c3d3b | 2155 | spin_lock_init(&md->uevent_lock); |
1da177e4 | 2156 | |
4a0b4ddf | 2157 | md->queue = blk_alloc_queue(GFP_KERNEL); |
1da177e4 | 2158 | if (!md->queue) |
6ed7ade8 | 2159 | goto bad_queue; |
1da177e4 | 2160 | |
4a0b4ddf | 2161 | dm_init_md_queue(md); |
9faf400f | 2162 | |
1da177e4 LT |
2163 | md->disk = alloc_disk(1); |
2164 | if (!md->disk) | |
6ed7ade8 | 2165 | goto bad_disk; |
1da177e4 | 2166 | |
316d315b NK |
2167 | atomic_set(&md->pending[0], 0); |
2168 | atomic_set(&md->pending[1], 0); | |
f0b04115 | 2169 | init_waitqueue_head(&md->wait); |
53d5914f | 2170 | INIT_WORK(&md->work, dm_wq_work); |
f0b04115 | 2171 | init_waitqueue_head(&md->eventq); |
2995fa78 | 2172 | init_completion(&md->kobj_holder.completion); |
2eb6e1e3 | 2173 | md->kworker_task = NULL; |
f0b04115 | 2174 | |
1da177e4 LT |
2175 | md->disk->major = _major; |
2176 | md->disk->first_minor = minor; | |
2177 | md->disk->fops = &dm_blk_dops; | |
2178 | md->disk->queue = md->queue; | |
2179 | md->disk->private_data = md; | |
2180 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
2181 | add_disk(md->disk); | |
7e51f257 | 2182 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 2183 | |
670368a8 | 2184 | md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0); |
304f3f6a MB |
2185 | if (!md->wq) |
2186 | goto bad_thread; | |
2187 | ||
32a926da MP |
2188 | md->bdev = bdget_disk(md->disk, 0); |
2189 | if (!md->bdev) | |
2190 | goto bad_bdev; | |
2191 | ||
6a8736d1 TH |
2192 | bio_init(&md->flush_bio); |
2193 | md->flush_bio.bi_bdev = md->bdev; | |
2194 | md->flush_bio.bi_rw = WRITE_FLUSH; | |
2195 | ||
fd2ed4d2 MP |
2196 | dm_stats_init(&md->stats); |
2197 | ||
ba61fdd1 | 2198 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 2199 | spin_lock(&_minor_lock); |
ba61fdd1 | 2200 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 2201 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
2202 | |
2203 | BUG_ON(old_md != MINOR_ALLOCED); | |
2204 | ||
1da177e4 LT |
2205 | return md; |
2206 | ||
32a926da MP |
2207 | bad_bdev: |
2208 | destroy_workqueue(md->wq); | |
304f3f6a | 2209 | bad_thread: |
03022c54 | 2210 | del_gendisk(md->disk); |
304f3f6a | 2211 | put_disk(md->disk); |
6ed7ade8 | 2212 | bad_disk: |
1312f40e | 2213 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 2214 | bad_queue: |
83d5e5b0 MP |
2215 | cleanup_srcu_struct(&md->io_barrier); |
2216 | bad_io_barrier: | |
1da177e4 | 2217 | free_minor(minor); |
6ed7ade8 | 2218 | bad_minor: |
10da4f79 | 2219 | module_put(THIS_MODULE); |
6ed7ade8 | 2220 | bad_module_get: |
1da177e4 LT |
2221 | kfree(md); |
2222 | return NULL; | |
2223 | } | |
2224 | ||
ae9da83f JN |
2225 | static void unlock_fs(struct mapped_device *md); |
2226 | ||
1da177e4 LT |
2227 | static void free_dev(struct mapped_device *md) |
2228 | { | |
f331c029 | 2229 | int minor = MINOR(disk_devt(md->disk)); |
63d94e48 | 2230 | |
32a926da | 2231 | unlock_fs(md); |
304f3f6a | 2232 | destroy_workqueue(md->wq); |
2eb6e1e3 KB |
2233 | |
2234 | if (md->kworker_task) | |
2235 | kthread_stop(md->kworker_task); | |
e6ee8c0b KU |
2236 | if (md->io_pool) |
2237 | mempool_destroy(md->io_pool); | |
1ae49ea2 MS |
2238 | if (md->rq_pool) |
2239 | mempool_destroy(md->rq_pool); | |
e6ee8c0b KU |
2240 | if (md->bs) |
2241 | bioset_free(md->bs); | |
63a4f065 | 2242 | |
83d5e5b0 | 2243 | cleanup_srcu_struct(&md->io_barrier); |
86f1152b | 2244 | free_table_devices(&md->table_devices); |
63a4f065 | 2245 | dm_stats_cleanup(&md->stats); |
fba9f90e JM |
2246 | |
2247 | spin_lock(&_minor_lock); | |
2248 | md->disk->private_data = NULL; | |
2249 | spin_unlock(&_minor_lock); | |
63a4f065 MS |
2250 | if (blk_get_integrity(md->disk)) |
2251 | blk_integrity_unregister(md->disk); | |
2252 | del_gendisk(md->disk); | |
1da177e4 | 2253 | put_disk(md->disk); |
1312f40e | 2254 | blk_cleanup_queue(md->queue); |
63a4f065 MS |
2255 | bdput(md->bdev); |
2256 | free_minor(minor); | |
2257 | ||
10da4f79 | 2258 | module_put(THIS_MODULE); |
1da177e4 LT |
2259 | kfree(md); |
2260 | } | |
2261 | ||
e6ee8c0b KU |
2262 | static void __bind_mempools(struct mapped_device *md, struct dm_table *t) |
2263 | { | |
c0820cf5 | 2264 | struct dm_md_mempools *p = dm_table_get_md_mempools(t); |
e6ee8c0b | 2265 | |
5f015204 | 2266 | if (md->io_pool && md->bs) { |
16245bdc JN |
2267 | /* The md already has necessary mempools. */ |
2268 | if (dm_table_get_type(t) == DM_TYPE_BIO_BASED) { | |
2269 | /* | |
2270 | * Reload bioset because front_pad may have changed | |
2271 | * because a different table was loaded. | |
2272 | */ | |
2273 | bioset_free(md->bs); | |
2274 | md->bs = p->bs; | |
2275 | p->bs = NULL; | |
16245bdc | 2276 | } |
466d89a6 KB |
2277 | /* |
2278 | * There's no need to reload with request-based dm | |
2279 | * because the size of front_pad doesn't change. | |
2280 | * Note for future: If you are to reload bioset, | |
2281 | * prep-ed requests in the queue may refer | |
2282 | * to bio from the old bioset, so you must walk | |
2283 | * through the queue to unprep. | |
2284 | */ | |
e6ee8c0b | 2285 | goto out; |
c0820cf5 | 2286 | } |
e6ee8c0b | 2287 | |
1ae49ea2 | 2288 | BUG_ON(!p || md->io_pool || md->rq_pool || md->bs); |
e6ee8c0b KU |
2289 | |
2290 | md->io_pool = p->io_pool; | |
2291 | p->io_pool = NULL; | |
1ae49ea2 MS |
2292 | md->rq_pool = p->rq_pool; |
2293 | p->rq_pool = NULL; | |
e6ee8c0b KU |
2294 | md->bs = p->bs; |
2295 | p->bs = NULL; | |
2296 | ||
2297 | out: | |
2298 | /* mempool bind completed, now no need any mempools in the table */ | |
2299 | dm_table_free_md_mempools(t); | |
2300 | } | |
2301 | ||
1da177e4 LT |
2302 | /* |
2303 | * Bind a table to the device. | |
2304 | */ | |
2305 | static void event_callback(void *context) | |
2306 | { | |
7a8c3d3b MA |
2307 | unsigned long flags; |
2308 | LIST_HEAD(uevents); | |
1da177e4 LT |
2309 | struct mapped_device *md = (struct mapped_device *) context; |
2310 | ||
7a8c3d3b MA |
2311 | spin_lock_irqsave(&md->uevent_lock, flags); |
2312 | list_splice_init(&md->uevent_list, &uevents); | |
2313 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2314 | ||
ed9e1982 | 2315 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
7a8c3d3b | 2316 | |
1da177e4 LT |
2317 | atomic_inc(&md->event_nr); |
2318 | wake_up(&md->eventq); | |
2319 | } | |
2320 | ||
c217649b MS |
2321 | /* |
2322 | * Protected by md->suspend_lock obtained by dm_swap_table(). | |
2323 | */ | |
4e90188b | 2324 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 2325 | { |
4e90188b | 2326 | set_capacity(md->disk, size); |
1da177e4 | 2327 | |
db8fef4f | 2328 | i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
1da177e4 LT |
2329 | } |
2330 | ||
d5b9dd04 MP |
2331 | /* |
2332 | * Return 1 if the queue has a compulsory merge_bvec_fn function. | |
2333 | * | |
2334 | * If this function returns 0, then the device is either a non-dm | |
2335 | * device without a merge_bvec_fn, or it is a dm device that is | |
2336 | * able to split any bios it receives that are too big. | |
2337 | */ | |
2338 | int dm_queue_merge_is_compulsory(struct request_queue *q) | |
2339 | { | |
2340 | struct mapped_device *dev_md; | |
2341 | ||
2342 | if (!q->merge_bvec_fn) | |
2343 | return 0; | |
2344 | ||
ff36ab34 | 2345 | if (q->make_request_fn == dm_make_request) { |
d5b9dd04 MP |
2346 | dev_md = q->queuedata; |
2347 | if (test_bit(DMF_MERGE_IS_OPTIONAL, &dev_md->flags)) | |
2348 | return 0; | |
2349 | } | |
2350 | ||
2351 | return 1; | |
2352 | } | |
2353 | ||
2354 | static int dm_device_merge_is_compulsory(struct dm_target *ti, | |
2355 | struct dm_dev *dev, sector_t start, | |
2356 | sector_t len, void *data) | |
2357 | { | |
2358 | struct block_device *bdev = dev->bdev; | |
2359 | struct request_queue *q = bdev_get_queue(bdev); | |
2360 | ||
2361 | return dm_queue_merge_is_compulsory(q); | |
2362 | } | |
2363 | ||
2364 | /* | |
2365 | * Return 1 if it is acceptable to ignore merge_bvec_fn based | |
2366 | * on the properties of the underlying devices. | |
2367 | */ | |
2368 | static int dm_table_merge_is_optional(struct dm_table *table) | |
2369 | { | |
2370 | unsigned i = 0; | |
2371 | struct dm_target *ti; | |
2372 | ||
2373 | while (i < dm_table_get_num_targets(table)) { | |
2374 | ti = dm_table_get_target(table, i++); | |
2375 | ||
2376 | if (ti->type->iterate_devices && | |
2377 | ti->type->iterate_devices(ti, dm_device_merge_is_compulsory, NULL)) | |
2378 | return 0; | |
2379 | } | |
2380 | ||
2381 | return 1; | |
2382 | } | |
2383 | ||
042d2a9b AK |
2384 | /* |
2385 | * Returns old map, which caller must destroy. | |
2386 | */ | |
2387 | static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, | |
2388 | struct queue_limits *limits) | |
1da177e4 | 2389 | { |
042d2a9b | 2390 | struct dm_table *old_map; |
165125e1 | 2391 | struct request_queue *q = md->queue; |
1da177e4 | 2392 | sector_t size; |
d5b9dd04 | 2393 | int merge_is_optional; |
1da177e4 LT |
2394 | |
2395 | size = dm_table_get_size(t); | |
3ac51e74 DW |
2396 | |
2397 | /* | |
2398 | * Wipe any geometry if the size of the table changed. | |
2399 | */ | |
fd2ed4d2 | 2400 | if (size != dm_get_size(md)) |
3ac51e74 DW |
2401 | memset(&md->geometry, 0, sizeof(md->geometry)); |
2402 | ||
32a926da | 2403 | __set_size(md, size); |
d5816876 | 2404 | |
2ca3310e AK |
2405 | dm_table_event_callback(t, event_callback, md); |
2406 | ||
e6ee8c0b KU |
2407 | /* |
2408 | * The queue hasn't been stopped yet, if the old table type wasn't | |
2409 | * for request-based during suspension. So stop it to prevent | |
2410 | * I/O mapping before resume. | |
2411 | * This must be done before setting the queue restrictions, | |
2412 | * because request-based dm may be run just after the setting. | |
2413 | */ | |
2414 | if (dm_table_request_based(t) && !blk_queue_stopped(q)) | |
2415 | stop_queue(q); | |
2416 | ||
2417 | __bind_mempools(md, t); | |
2418 | ||
d5b9dd04 MP |
2419 | merge_is_optional = dm_table_merge_is_optional(t); |
2420 | ||
a12f5d48 | 2421 | old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
83d5e5b0 | 2422 | rcu_assign_pointer(md->map, t); |
36a0456f AK |
2423 | md->immutable_target_type = dm_table_get_immutable_target_type(t); |
2424 | ||
754c5fc7 | 2425 | dm_table_set_restrictions(t, q, limits); |
d5b9dd04 MP |
2426 | if (merge_is_optional) |
2427 | set_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
2428 | else | |
2429 | clear_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
41abc4e1 HR |
2430 | if (old_map) |
2431 | dm_sync_table(md); | |
1da177e4 | 2432 | |
042d2a9b | 2433 | return old_map; |
1da177e4 LT |
2434 | } |
2435 | ||
a7940155 AK |
2436 | /* |
2437 | * Returns unbound table for the caller to free. | |
2438 | */ | |
2439 | static struct dm_table *__unbind(struct mapped_device *md) | |
1da177e4 | 2440 | { |
a12f5d48 | 2441 | struct dm_table *map = rcu_dereference_protected(md->map, 1); |
1da177e4 LT |
2442 | |
2443 | if (!map) | |
a7940155 | 2444 | return NULL; |
1da177e4 LT |
2445 | |
2446 | dm_table_event_callback(map, NULL, NULL); | |
9cdb8520 | 2447 | RCU_INIT_POINTER(md->map, NULL); |
83d5e5b0 | 2448 | dm_sync_table(md); |
a7940155 AK |
2449 | |
2450 | return map; | |
1da177e4 LT |
2451 | } |
2452 | ||
2453 | /* | |
2454 | * Constructor for a new device. | |
2455 | */ | |
2b06cfff | 2456 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
2457 | { |
2458 | struct mapped_device *md; | |
2459 | ||
2b06cfff | 2460 | md = alloc_dev(minor); |
1da177e4 LT |
2461 | if (!md) |
2462 | return -ENXIO; | |
2463 | ||
784aae73 MB |
2464 | dm_sysfs_init(md); |
2465 | ||
1da177e4 LT |
2466 | *result = md; |
2467 | return 0; | |
2468 | } | |
2469 | ||
a5664dad MS |
2470 | /* |
2471 | * Functions to manage md->type. | |
2472 | * All are required to hold md->type_lock. | |
2473 | */ | |
2474 | void dm_lock_md_type(struct mapped_device *md) | |
2475 | { | |
2476 | mutex_lock(&md->type_lock); | |
2477 | } | |
2478 | ||
2479 | void dm_unlock_md_type(struct mapped_device *md) | |
2480 | { | |
2481 | mutex_unlock(&md->type_lock); | |
2482 | } | |
2483 | ||
2484 | void dm_set_md_type(struct mapped_device *md, unsigned type) | |
2485 | { | |
00c4fc3b | 2486 | BUG_ON(!mutex_is_locked(&md->type_lock)); |
a5664dad MS |
2487 | md->type = type; |
2488 | } | |
2489 | ||
2490 | unsigned dm_get_md_type(struct mapped_device *md) | |
2491 | { | |
00c4fc3b | 2492 | BUG_ON(!mutex_is_locked(&md->type_lock)); |
a5664dad MS |
2493 | return md->type; |
2494 | } | |
2495 | ||
e5863d9a MS |
2496 | static bool dm_md_type_request_based(struct mapped_device *md) |
2497 | { | |
2498 | unsigned table_type = dm_get_md_type(md); | |
2499 | ||
2500 | return (table_type == DM_TYPE_REQUEST_BASED || | |
2501 | table_type == DM_TYPE_MQ_REQUEST_BASED); | |
2502 | } | |
2503 | ||
36a0456f AK |
2504 | struct target_type *dm_get_immutable_target_type(struct mapped_device *md) |
2505 | { | |
2506 | return md->immutable_target_type; | |
2507 | } | |
2508 | ||
f84cb8a4 MS |
2509 | /* |
2510 | * The queue_limits are only valid as long as you have a reference | |
2511 | * count on 'md'. | |
2512 | */ | |
2513 | struct queue_limits *dm_get_queue_limits(struct mapped_device *md) | |
2514 | { | |
2515 | BUG_ON(!atomic_read(&md->holders)); | |
2516 | return &md->queue->limits; | |
2517 | } | |
2518 | EXPORT_SYMBOL_GPL(dm_get_queue_limits); | |
2519 | ||
4a0b4ddf MS |
2520 | /* |
2521 | * Fully initialize a request-based queue (->elevator, ->request_fn, etc). | |
2522 | */ | |
2523 | static int dm_init_request_based_queue(struct mapped_device *md) | |
2524 | { | |
2525 | struct request_queue *q = NULL; | |
2526 | ||
2527 | if (md->queue->elevator) | |
2528 | return 1; | |
2529 | ||
2530 | /* Fully initialize the queue */ | |
2531 | q = blk_init_allocated_queue(md->queue, dm_request_fn, NULL); | |
2532 | if (!q) | |
2533 | return 0; | |
2534 | ||
2535 | md->queue = q; | |
4a0b4ddf MS |
2536 | dm_init_md_queue(md); |
2537 | blk_queue_softirq_done(md->queue, dm_softirq_done); | |
2538 | blk_queue_prep_rq(md->queue, dm_prep_fn); | |
4a0b4ddf | 2539 | |
2eb6e1e3 KB |
2540 | /* Also initialize the request-based DM worker thread */ |
2541 | init_kthread_worker(&md->kworker); | |
2542 | md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker, | |
2543 | "kdmwork-%s", dm_device_name(md)); | |
2544 | ||
4a0b4ddf MS |
2545 | elv_register_queue(md->queue); |
2546 | ||
2547 | return 1; | |
2548 | } | |
2549 | ||
2550 | /* | |
2551 | * Setup the DM device's queue based on md's type | |
2552 | */ | |
2553 | int dm_setup_md_queue(struct mapped_device *md) | |
2554 | { | |
ff36ab34 MS |
2555 | if (dm_md_type_request_based(md)) { |
2556 | if (!dm_init_request_based_queue(md)) { | |
2557 | DMWARN("Cannot initialize queue for request-based mapped device"); | |
2558 | return -EINVAL; | |
2559 | } | |
2560 | } else { | |
2561 | /* bio-based specific initialization */ | |
2562 | blk_queue_make_request(md->queue, dm_make_request); | |
2563 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); | |
4a0b4ddf MS |
2564 | } |
2565 | ||
2566 | return 0; | |
2567 | } | |
2568 | ||
2bec1f4a | 2569 | struct mapped_device *dm_get_md(dev_t dev) |
1da177e4 LT |
2570 | { |
2571 | struct mapped_device *md; | |
1da177e4 LT |
2572 | unsigned minor = MINOR(dev); |
2573 | ||
2574 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
2575 | return NULL; | |
2576 | ||
f32c10b0 | 2577 | spin_lock(&_minor_lock); |
1da177e4 LT |
2578 | |
2579 | md = idr_find(&_minor_idr, minor); | |
2bec1f4a MP |
2580 | if (md) { |
2581 | if ((md == MINOR_ALLOCED || | |
2582 | (MINOR(disk_devt(dm_disk(md))) != minor) || | |
2583 | dm_deleting_md(md) || | |
2584 | test_bit(DMF_FREEING, &md->flags))) { | |
2585 | md = NULL; | |
2586 | goto out; | |
2587 | } | |
2588 | dm_get(md); | |
fba9f90e | 2589 | } |
1da177e4 | 2590 | |
fba9f90e | 2591 | out: |
f32c10b0 | 2592 | spin_unlock(&_minor_lock); |
1da177e4 | 2593 | |
637842cf DT |
2594 | return md; |
2595 | } | |
3cf2e4ba | 2596 | EXPORT_SYMBOL_GPL(dm_get_md); |
d229a958 | 2597 | |
9ade92a9 | 2598 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 2599 | { |
9ade92a9 | 2600 | return md->interface_ptr; |
1da177e4 LT |
2601 | } |
2602 | ||
2603 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
2604 | { | |
2605 | md->interface_ptr = ptr; | |
2606 | } | |
2607 | ||
2608 | void dm_get(struct mapped_device *md) | |
2609 | { | |
2610 | atomic_inc(&md->holders); | |
3f77316d | 2611 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
1da177e4 LT |
2612 | } |
2613 | ||
09ee96b2 MP |
2614 | int dm_hold(struct mapped_device *md) |
2615 | { | |
2616 | spin_lock(&_minor_lock); | |
2617 | if (test_bit(DMF_FREEING, &md->flags)) { | |
2618 | spin_unlock(&_minor_lock); | |
2619 | return -EBUSY; | |
2620 | } | |
2621 | dm_get(md); | |
2622 | spin_unlock(&_minor_lock); | |
2623 | return 0; | |
2624 | } | |
2625 | EXPORT_SYMBOL_GPL(dm_hold); | |
2626 | ||
72d94861 AK |
2627 | const char *dm_device_name(struct mapped_device *md) |
2628 | { | |
2629 | return md->name; | |
2630 | } | |
2631 | EXPORT_SYMBOL_GPL(dm_device_name); | |
2632 | ||
3f77316d | 2633 | static void __dm_destroy(struct mapped_device *md, bool wait) |
1da177e4 | 2634 | { |
1134e5ae | 2635 | struct dm_table *map; |
83d5e5b0 | 2636 | int srcu_idx; |
1da177e4 | 2637 | |
3f77316d | 2638 | might_sleep(); |
fba9f90e | 2639 | |
83d5e5b0 | 2640 | map = dm_get_live_table(md, &srcu_idx); |
63a4f065 MS |
2641 | |
2642 | spin_lock(&_minor_lock); | |
3f77316d KU |
2643 | idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); |
2644 | set_bit(DMF_FREEING, &md->flags); | |
2645 | spin_unlock(&_minor_lock); | |
2646 | ||
2eb6e1e3 KB |
2647 | if (dm_request_based(md)) |
2648 | flush_kthread_worker(&md->kworker); | |
2649 | ||
ab7c7bb6 MP |
2650 | /* |
2651 | * Take suspend_lock so that presuspend and postsuspend methods | |
2652 | * do not race with internal suspend. | |
2653 | */ | |
2654 | mutex_lock(&md->suspend_lock); | |
3f77316d KU |
2655 | if (!dm_suspended_md(md)) { |
2656 | dm_table_presuspend_targets(map); | |
2657 | dm_table_postsuspend_targets(map); | |
1da177e4 | 2658 | } |
ab7c7bb6 | 2659 | mutex_unlock(&md->suspend_lock); |
3f77316d | 2660 | |
83d5e5b0 MP |
2661 | /* dm_put_live_table must be before msleep, otherwise deadlock is possible */ |
2662 | dm_put_live_table(md, srcu_idx); | |
2663 | ||
3f77316d KU |
2664 | /* |
2665 | * Rare, but there may be I/O requests still going to complete, | |
2666 | * for example. Wait for all references to disappear. | |
2667 | * No one should increment the reference count of the mapped_device, | |
2668 | * after the mapped_device state becomes DMF_FREEING. | |
2669 | */ | |
2670 | if (wait) | |
2671 | while (atomic_read(&md->holders)) | |
2672 | msleep(1); | |
2673 | else if (atomic_read(&md->holders)) | |
2674 | DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", | |
2675 | dm_device_name(md), atomic_read(&md->holders)); | |
2676 | ||
2677 | dm_sysfs_exit(md); | |
3f77316d KU |
2678 | dm_table_destroy(__unbind(md)); |
2679 | free_dev(md); | |
2680 | } | |
2681 | ||
2682 | void dm_destroy(struct mapped_device *md) | |
2683 | { | |
2684 | __dm_destroy(md, true); | |
2685 | } | |
2686 | ||
2687 | void dm_destroy_immediate(struct mapped_device *md) | |
2688 | { | |
2689 | __dm_destroy(md, false); | |
2690 | } | |
2691 | ||
2692 | void dm_put(struct mapped_device *md) | |
2693 | { | |
2694 | atomic_dec(&md->holders); | |
1da177e4 | 2695 | } |
79eb885c | 2696 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 2697 | |
401600df | 2698 | static int dm_wait_for_completion(struct mapped_device *md, int interruptible) |
46125c1c MB |
2699 | { |
2700 | int r = 0; | |
b44ebeb0 MP |
2701 | DECLARE_WAITQUEUE(wait, current); |
2702 | ||
b44ebeb0 | 2703 | add_wait_queue(&md->wait, &wait); |
46125c1c MB |
2704 | |
2705 | while (1) { | |
401600df | 2706 | set_current_state(interruptible); |
46125c1c | 2707 | |
b4324fee | 2708 | if (!md_in_flight(md)) |
46125c1c MB |
2709 | break; |
2710 | ||
401600df MP |
2711 | if (interruptible == TASK_INTERRUPTIBLE && |
2712 | signal_pending(current)) { | |
46125c1c MB |
2713 | r = -EINTR; |
2714 | break; | |
2715 | } | |
2716 | ||
2717 | io_schedule(); | |
2718 | } | |
2719 | set_current_state(TASK_RUNNING); | |
2720 | ||
b44ebeb0 MP |
2721 | remove_wait_queue(&md->wait, &wait); |
2722 | ||
46125c1c MB |
2723 | return r; |
2724 | } | |
2725 | ||
1da177e4 LT |
2726 | /* |
2727 | * Process the deferred bios | |
2728 | */ | |
ef208587 | 2729 | static void dm_wq_work(struct work_struct *work) |
1da177e4 | 2730 | { |
ef208587 MP |
2731 | struct mapped_device *md = container_of(work, struct mapped_device, |
2732 | work); | |
6d6f10df | 2733 | struct bio *c; |
83d5e5b0 MP |
2734 | int srcu_idx; |
2735 | struct dm_table *map; | |
1da177e4 | 2736 | |
83d5e5b0 | 2737 | map = dm_get_live_table(md, &srcu_idx); |
ef208587 | 2738 | |
3b00b203 | 2739 | while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
df12ee99 AK |
2740 | spin_lock_irq(&md->deferred_lock); |
2741 | c = bio_list_pop(&md->deferred); | |
2742 | spin_unlock_irq(&md->deferred_lock); | |
2743 | ||
6a8736d1 | 2744 | if (!c) |
df12ee99 | 2745 | break; |
022c2611 | 2746 | |
e6ee8c0b KU |
2747 | if (dm_request_based(md)) |
2748 | generic_make_request(c); | |
6a8736d1 | 2749 | else |
83d5e5b0 | 2750 | __split_and_process_bio(md, map, c); |
022c2611 | 2751 | } |
73d410c0 | 2752 | |
83d5e5b0 | 2753 | dm_put_live_table(md, srcu_idx); |
1da177e4 LT |
2754 | } |
2755 | ||
9a1fb464 | 2756 | static void dm_queue_flush(struct mapped_device *md) |
304f3f6a | 2757 | { |
3b00b203 | 2758 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
4e857c58 | 2759 | smp_mb__after_atomic(); |
53d5914f | 2760 | queue_work(md->wq, &md->work); |
304f3f6a MB |
2761 | } |
2762 | ||
1da177e4 | 2763 | /* |
042d2a9b | 2764 | * Swap in a new table, returning the old one for the caller to destroy. |
1da177e4 | 2765 | */ |
042d2a9b | 2766 | struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) |
1da177e4 | 2767 | { |
87eb5b21 | 2768 | struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL); |
754c5fc7 | 2769 | struct queue_limits limits; |
042d2a9b | 2770 | int r; |
1da177e4 | 2771 | |
e61290a4 | 2772 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
2773 | |
2774 | /* device must be suspended */ | |
4f186f8b | 2775 | if (!dm_suspended_md(md)) |
93c534ae | 2776 | goto out; |
1da177e4 | 2777 | |
3ae70656 MS |
2778 | /* |
2779 | * If the new table has no data devices, retain the existing limits. | |
2780 | * This helps multipath with queue_if_no_path if all paths disappear, | |
2781 | * then new I/O is queued based on these limits, and then some paths | |
2782 | * reappear. | |
2783 | */ | |
2784 | if (dm_table_has_no_data_devices(table)) { | |
83d5e5b0 | 2785 | live_map = dm_get_live_table_fast(md); |
3ae70656 MS |
2786 | if (live_map) |
2787 | limits = md->queue->limits; | |
83d5e5b0 | 2788 | dm_put_live_table_fast(md); |
3ae70656 MS |
2789 | } |
2790 | ||
87eb5b21 MC |
2791 | if (!live_map) { |
2792 | r = dm_calculate_queue_limits(table, &limits); | |
2793 | if (r) { | |
2794 | map = ERR_PTR(r); | |
2795 | goto out; | |
2796 | } | |
042d2a9b | 2797 | } |
754c5fc7 | 2798 | |
042d2a9b | 2799 | map = __bind(md, table, &limits); |
1da177e4 | 2800 | |
93c534ae | 2801 | out: |
e61290a4 | 2802 | mutex_unlock(&md->suspend_lock); |
042d2a9b | 2803 | return map; |
1da177e4 LT |
2804 | } |
2805 | ||
2806 | /* | |
2807 | * Functions to lock and unlock any filesystem running on the | |
2808 | * device. | |
2809 | */ | |
2ca3310e | 2810 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 2811 | { |
e39e2e95 | 2812 | int r; |
1da177e4 LT |
2813 | |
2814 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 2815 | |
db8fef4f | 2816 | md->frozen_sb = freeze_bdev(md->bdev); |
dfbe03f6 | 2817 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 2818 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
2819 | md->frozen_sb = NULL; |
2820 | return r; | |
dfbe03f6 AK |
2821 | } |
2822 | ||
aa8d7c2f AK |
2823 | set_bit(DMF_FROZEN, &md->flags); |
2824 | ||
1da177e4 LT |
2825 | return 0; |
2826 | } | |
2827 | ||
2ca3310e | 2828 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 2829 | { |
aa8d7c2f AK |
2830 | if (!test_bit(DMF_FROZEN, &md->flags)) |
2831 | return; | |
2832 | ||
db8fef4f | 2833 | thaw_bdev(md->bdev, md->frozen_sb); |
1da177e4 | 2834 | md->frozen_sb = NULL; |
aa8d7c2f | 2835 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
2836 | } |
2837 | ||
2838 | /* | |
ffcc3936 MS |
2839 | * If __dm_suspend returns 0, the device is completely quiescent |
2840 | * now. There is no request-processing activity. All new requests | |
2841 | * are being added to md->deferred list. | |
cec47e3d | 2842 | * |
ffcc3936 | 2843 | * Caller must hold md->suspend_lock |
cec47e3d | 2844 | */ |
ffcc3936 MS |
2845 | static int __dm_suspend(struct mapped_device *md, struct dm_table *map, |
2846 | unsigned suspend_flags, int interruptible) | |
1da177e4 | 2847 | { |
ffcc3936 MS |
2848 | bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG; |
2849 | bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG; | |
2850 | int r; | |
1da177e4 | 2851 | |
2e93ccc1 KU |
2852 | /* |
2853 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
2854 | * This flag is cleared before dm_suspend returns. | |
2855 | */ | |
2856 | if (noflush) | |
2857 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
2858 | ||
d67ee213 MS |
2859 | /* |
2860 | * This gets reverted if there's an error later and the targets | |
2861 | * provide the .presuspend_undo hook. | |
2862 | */ | |
cf222b37 AK |
2863 | dm_table_presuspend_targets(map); |
2864 | ||
32a926da | 2865 | /* |
9f518b27 KU |
2866 | * Flush I/O to the device. |
2867 | * Any I/O submitted after lock_fs() may not be flushed. | |
2868 | * noflush takes precedence over do_lockfs. | |
2869 | * (lock_fs() flushes I/Os and waits for them to complete.) | |
32a926da MP |
2870 | */ |
2871 | if (!noflush && do_lockfs) { | |
2872 | r = lock_fs(md); | |
d67ee213 MS |
2873 | if (r) { |
2874 | dm_table_presuspend_undo_targets(map); | |
ffcc3936 | 2875 | return r; |
d67ee213 | 2876 | } |
aa8d7c2f | 2877 | } |
1da177e4 LT |
2878 | |
2879 | /* | |
3b00b203 MP |
2880 | * Here we must make sure that no processes are submitting requests |
2881 | * to target drivers i.e. no one may be executing | |
2882 | * __split_and_process_bio. This is called from dm_request and | |
2883 | * dm_wq_work. | |
2884 | * | |
2885 | * To get all processes out of __split_and_process_bio in dm_request, | |
2886 | * we take the write lock. To prevent any process from reentering | |
6a8736d1 TH |
2887 | * __split_and_process_bio from dm_request and quiesce the thread |
2888 | * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call | |
2889 | * flush_workqueue(md->wq). | |
1da177e4 | 2890 | */ |
1eb787ec | 2891 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
41abc4e1 HR |
2892 | if (map) |
2893 | synchronize_srcu(&md->io_barrier); | |
1da177e4 | 2894 | |
d0bcb878 | 2895 | /* |
29e4013d TH |
2896 | * Stop md->queue before flushing md->wq in case request-based |
2897 | * dm defers requests to md->wq from md->queue. | |
d0bcb878 | 2898 | */ |
2eb6e1e3 | 2899 | if (dm_request_based(md)) { |
9f518b27 | 2900 | stop_queue(md->queue); |
2eb6e1e3 KB |
2901 | flush_kthread_worker(&md->kworker); |
2902 | } | |
cec47e3d | 2903 | |
d0bcb878 KU |
2904 | flush_workqueue(md->wq); |
2905 | ||
1da177e4 | 2906 | /* |
3b00b203 MP |
2907 | * At this point no more requests are entering target request routines. |
2908 | * We call dm_wait_for_completion to wait for all existing requests | |
2909 | * to finish. | |
1da177e4 | 2910 | */ |
ffcc3936 | 2911 | r = dm_wait_for_completion(md, interruptible); |
1da177e4 | 2912 | |
6d6f10df | 2913 | if (noflush) |
022c2611 | 2914 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
41abc4e1 HR |
2915 | if (map) |
2916 | synchronize_srcu(&md->io_barrier); | |
2e93ccc1 | 2917 | |
1da177e4 | 2918 | /* were we interrupted ? */ |
46125c1c | 2919 | if (r < 0) { |
9a1fb464 | 2920 | dm_queue_flush(md); |
73d410c0 | 2921 | |
cec47e3d | 2922 | if (dm_request_based(md)) |
9f518b27 | 2923 | start_queue(md->queue); |
cec47e3d | 2924 | |
2ca3310e | 2925 | unlock_fs(md); |
d67ee213 | 2926 | dm_table_presuspend_undo_targets(map); |
ffcc3936 | 2927 | /* pushback list is already flushed, so skip flush */ |
2ca3310e | 2928 | } |
1da177e4 | 2929 | |
ffcc3936 MS |
2930 | return r; |
2931 | } | |
2932 | ||
2933 | /* | |
2934 | * We need to be able to change a mapping table under a mounted | |
2935 | * filesystem. For example we might want to move some data in | |
2936 | * the background. Before the table can be swapped with | |
2937 | * dm_bind_table, dm_suspend must be called to flush any in | |
2938 | * flight bios and ensure that any further io gets deferred. | |
2939 | */ | |
2940 | /* | |
2941 | * Suspend mechanism in request-based dm. | |
2942 | * | |
2943 | * 1. Flush all I/Os by lock_fs() if needed. | |
2944 | * 2. Stop dispatching any I/O by stopping the request_queue. | |
2945 | * 3. Wait for all in-flight I/Os to be completed or requeued. | |
2946 | * | |
2947 | * To abort suspend, start the request_queue. | |
2948 | */ | |
2949 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) | |
2950 | { | |
2951 | struct dm_table *map = NULL; | |
2952 | int r = 0; | |
2953 | ||
2954 | retry: | |
2955 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
2956 | ||
2957 | if (dm_suspended_md(md)) { | |
2958 | r = -EINVAL; | |
2959 | goto out_unlock; | |
2960 | } | |
2961 | ||
2962 | if (dm_suspended_internally_md(md)) { | |
2963 | /* already internally suspended, wait for internal resume */ | |
2964 | mutex_unlock(&md->suspend_lock); | |
2965 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
2966 | if (r) | |
2967 | return r; | |
2968 | goto retry; | |
2969 | } | |
2970 | ||
a12f5d48 | 2971 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
ffcc3936 MS |
2972 | |
2973 | r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE); | |
2974 | if (r) | |
2975 | goto out_unlock; | |
3b00b203 | 2976 | |
2ca3310e | 2977 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 2978 | |
4d4471cb KU |
2979 | dm_table_postsuspend_targets(map); |
2980 | ||
d287483d | 2981 | out_unlock: |
e61290a4 | 2982 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 2983 | return r; |
1da177e4 LT |
2984 | } |
2985 | ||
ffcc3936 MS |
2986 | static int __dm_resume(struct mapped_device *md, struct dm_table *map) |
2987 | { | |
2988 | if (map) { | |
2989 | int r = dm_table_resume_targets(map); | |
2990 | if (r) | |
2991 | return r; | |
2992 | } | |
2993 | ||
2994 | dm_queue_flush(md); | |
2995 | ||
2996 | /* | |
2997 | * Flushing deferred I/Os must be done after targets are resumed | |
2998 | * so that mapping of targets can work correctly. | |
2999 | * Request-based dm is queueing the deferred I/Os in its request_queue. | |
3000 | */ | |
3001 | if (dm_request_based(md)) | |
3002 | start_queue(md->queue); | |
3003 | ||
3004 | unlock_fs(md); | |
3005 | ||
3006 | return 0; | |
3007 | } | |
3008 | ||
1da177e4 LT |
3009 | int dm_resume(struct mapped_device *md) |
3010 | { | |
cf222b37 | 3011 | int r = -EINVAL; |
cf222b37 | 3012 | struct dm_table *map = NULL; |
1da177e4 | 3013 | |
ffcc3936 MS |
3014 | retry: |
3015 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
3016 | ||
4f186f8b | 3017 | if (!dm_suspended_md(md)) |
cf222b37 | 3018 | goto out; |
cf222b37 | 3019 | |
ffcc3936 MS |
3020 | if (dm_suspended_internally_md(md)) { |
3021 | /* already internally suspended, wait for internal resume */ | |
3022 | mutex_unlock(&md->suspend_lock); | |
3023 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
3024 | if (r) | |
3025 | return r; | |
3026 | goto retry; | |
3027 | } | |
3028 | ||
a12f5d48 | 3029 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
2ca3310e | 3030 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 3031 | goto out; |
1da177e4 | 3032 | |
ffcc3936 | 3033 | r = __dm_resume(md, map); |
8757b776 MB |
3034 | if (r) |
3035 | goto out; | |
2ca3310e | 3036 | |
2ca3310e AK |
3037 | clear_bit(DMF_SUSPENDED, &md->flags); |
3038 | ||
cf222b37 AK |
3039 | r = 0; |
3040 | out: | |
e61290a4 | 3041 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 3042 | |
cf222b37 | 3043 | return r; |
1da177e4 LT |
3044 | } |
3045 | ||
fd2ed4d2 MP |
3046 | /* |
3047 | * Internal suspend/resume works like userspace-driven suspend. It waits | |
3048 | * until all bios finish and prevents issuing new bios to the target drivers. | |
3049 | * It may be used only from the kernel. | |
fd2ed4d2 MP |
3050 | */ |
3051 | ||
ffcc3936 | 3052 | static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags) |
fd2ed4d2 | 3053 | { |
ffcc3936 MS |
3054 | struct dm_table *map = NULL; |
3055 | ||
96b26c8c | 3056 | if (md->internal_suspend_count++) |
ffcc3936 MS |
3057 | return; /* nested internal suspend */ |
3058 | ||
3059 | if (dm_suspended_md(md)) { | |
3060 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3061 | return; /* nest suspend */ | |
3062 | } | |
3063 | ||
a12f5d48 | 3064 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
ffcc3936 MS |
3065 | |
3066 | /* | |
3067 | * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is | |
3068 | * supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend | |
3069 | * would require changing .presuspend to return an error -- avoid this | |
3070 | * until there is a need for more elaborate variants of internal suspend. | |
3071 | */ | |
3072 | (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE); | |
3073 | ||
3074 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3075 | ||
3076 | dm_table_postsuspend_targets(map); | |
3077 | } | |
3078 | ||
3079 | static void __dm_internal_resume(struct mapped_device *md) | |
3080 | { | |
96b26c8c MP |
3081 | BUG_ON(!md->internal_suspend_count); |
3082 | ||
3083 | if (--md->internal_suspend_count) | |
ffcc3936 MS |
3084 | return; /* resume from nested internal suspend */ |
3085 | ||
fd2ed4d2 | 3086 | if (dm_suspended_md(md)) |
ffcc3936 MS |
3087 | goto done; /* resume from nested suspend */ |
3088 | ||
3089 | /* | |
3090 | * NOTE: existing callers don't need to call dm_table_resume_targets | |
3091 | * (which may fail -- so best to avoid it for now by passing NULL map) | |
3092 | */ | |
3093 | (void) __dm_resume(md, NULL); | |
3094 | ||
3095 | done: | |
3096 | clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3097 | smp_mb__after_atomic(); | |
3098 | wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY); | |
3099 | } | |
3100 | ||
3101 | void dm_internal_suspend_noflush(struct mapped_device *md) | |
3102 | { | |
3103 | mutex_lock(&md->suspend_lock); | |
3104 | __dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG); | |
3105 | mutex_unlock(&md->suspend_lock); | |
3106 | } | |
3107 | EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush); | |
3108 | ||
3109 | void dm_internal_resume(struct mapped_device *md) | |
3110 | { | |
3111 | mutex_lock(&md->suspend_lock); | |
3112 | __dm_internal_resume(md); | |
3113 | mutex_unlock(&md->suspend_lock); | |
3114 | } | |
3115 | EXPORT_SYMBOL_GPL(dm_internal_resume); | |
3116 | ||
3117 | /* | |
3118 | * Fast variants of internal suspend/resume hold md->suspend_lock, | |
3119 | * which prevents interaction with userspace-driven suspend. | |
3120 | */ | |
3121 | ||
3122 | void dm_internal_suspend_fast(struct mapped_device *md) | |
3123 | { | |
3124 | mutex_lock(&md->suspend_lock); | |
3125 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) | |
fd2ed4d2 MP |
3126 | return; |
3127 | ||
3128 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); | |
3129 | synchronize_srcu(&md->io_barrier); | |
3130 | flush_workqueue(md->wq); | |
3131 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); | |
3132 | } | |
b735fede | 3133 | EXPORT_SYMBOL_GPL(dm_internal_suspend_fast); |
fd2ed4d2 | 3134 | |
ffcc3936 | 3135 | void dm_internal_resume_fast(struct mapped_device *md) |
fd2ed4d2 | 3136 | { |
ffcc3936 | 3137 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) |
fd2ed4d2 MP |
3138 | goto done; |
3139 | ||
3140 | dm_queue_flush(md); | |
3141 | ||
3142 | done: | |
3143 | mutex_unlock(&md->suspend_lock); | |
3144 | } | |
b735fede | 3145 | EXPORT_SYMBOL_GPL(dm_internal_resume_fast); |
fd2ed4d2 | 3146 | |
1da177e4 LT |
3147 | /*----------------------------------------------------------------- |
3148 | * Event notification. | |
3149 | *---------------------------------------------------------------*/ | |
3abf85b5 | 3150 | int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
60935eb2 | 3151 | unsigned cookie) |
69267a30 | 3152 | { |
60935eb2 MB |
3153 | char udev_cookie[DM_COOKIE_LENGTH]; |
3154 | char *envp[] = { udev_cookie, NULL }; | |
3155 | ||
3156 | if (!cookie) | |
3abf85b5 | 3157 | return kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
60935eb2 MB |
3158 | else { |
3159 | snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", | |
3160 | DM_COOKIE_ENV_VAR_NAME, cookie); | |
3abf85b5 PR |
3161 | return kobject_uevent_env(&disk_to_dev(md->disk)->kobj, |
3162 | action, envp); | |
60935eb2 | 3163 | } |
69267a30 AK |
3164 | } |
3165 | ||
7a8c3d3b MA |
3166 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
3167 | { | |
3168 | return atomic_add_return(1, &md->uevent_seq); | |
3169 | } | |
3170 | ||
1da177e4 LT |
3171 | uint32_t dm_get_event_nr(struct mapped_device *md) |
3172 | { | |
3173 | return atomic_read(&md->event_nr); | |
3174 | } | |
3175 | ||
3176 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
3177 | { | |
3178 | return wait_event_interruptible(md->eventq, | |
3179 | (event_nr != atomic_read(&md->event_nr))); | |
3180 | } | |
3181 | ||
7a8c3d3b MA |
3182 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
3183 | { | |
3184 | unsigned long flags; | |
3185 | ||
3186 | spin_lock_irqsave(&md->uevent_lock, flags); | |
3187 | list_add(elist, &md->uevent_list); | |
3188 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
3189 | } | |
3190 | ||
1da177e4 LT |
3191 | /* |
3192 | * The gendisk is only valid as long as you have a reference | |
3193 | * count on 'md'. | |
3194 | */ | |
3195 | struct gendisk *dm_disk(struct mapped_device *md) | |
3196 | { | |
3197 | return md->disk; | |
3198 | } | |
3199 | ||
784aae73 MB |
3200 | struct kobject *dm_kobject(struct mapped_device *md) |
3201 | { | |
2995fa78 | 3202 | return &md->kobj_holder.kobj; |
784aae73 MB |
3203 | } |
3204 | ||
784aae73 MB |
3205 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) |
3206 | { | |
3207 | struct mapped_device *md; | |
3208 | ||
2995fa78 | 3209 | md = container_of(kobj, struct mapped_device, kobj_holder.kobj); |
784aae73 | 3210 | |
4d89b7b4 | 3211 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 3212 | dm_deleting_md(md)) |
4d89b7b4 MB |
3213 | return NULL; |
3214 | ||
784aae73 MB |
3215 | dm_get(md); |
3216 | return md; | |
3217 | } | |
3218 | ||
4f186f8b | 3219 | int dm_suspended_md(struct mapped_device *md) |
1da177e4 LT |
3220 | { |
3221 | return test_bit(DMF_SUSPENDED, &md->flags); | |
3222 | } | |
3223 | ||
ffcc3936 MS |
3224 | int dm_suspended_internally_md(struct mapped_device *md) |
3225 | { | |
3226 | return test_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3227 | } | |
3228 | ||
2c140a24 MP |
3229 | int dm_test_deferred_remove_flag(struct mapped_device *md) |
3230 | { | |
3231 | return test_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
3232 | } | |
3233 | ||
64dbce58 KU |
3234 | int dm_suspended(struct dm_target *ti) |
3235 | { | |
ecdb2e25 | 3236 | return dm_suspended_md(dm_table_get_md(ti->table)); |
64dbce58 KU |
3237 | } |
3238 | EXPORT_SYMBOL_GPL(dm_suspended); | |
3239 | ||
2e93ccc1 KU |
3240 | int dm_noflush_suspending(struct dm_target *ti) |
3241 | { | |
ecdb2e25 | 3242 | return __noflush_suspending(dm_table_get_md(ti->table)); |
2e93ccc1 KU |
3243 | } |
3244 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
3245 | ||
c0820cf5 | 3246 | struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, unsigned per_bio_data_size) |
e6ee8c0b | 3247 | { |
5f015204 JN |
3248 | struct dm_md_mempools *pools = kzalloc(sizeof(*pools), GFP_KERNEL); |
3249 | struct kmem_cache *cachep; | |
e5863d9a | 3250 | unsigned int pool_size = 0; |
5f015204 | 3251 | unsigned int front_pad; |
e6ee8c0b KU |
3252 | |
3253 | if (!pools) | |
3254 | return NULL; | |
3255 | ||
e5863d9a MS |
3256 | switch (type) { |
3257 | case DM_TYPE_BIO_BASED: | |
5f015204 | 3258 | cachep = _io_cache; |
e8603136 | 3259 | pool_size = dm_get_reserved_bio_based_ios(); |
5f015204 | 3260 | front_pad = roundup(per_bio_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone); |
e5863d9a MS |
3261 | break; |
3262 | case DM_TYPE_REQUEST_BASED: | |
f4790826 | 3263 | pool_size = dm_get_reserved_rq_based_ios(); |
1ae49ea2 MS |
3264 | pools->rq_pool = mempool_create_slab_pool(pool_size, _rq_cache); |
3265 | if (!pools->rq_pool) | |
3266 | goto out; | |
e5863d9a MS |
3267 | /* fall through to setup remaining rq-based pools */ |
3268 | case DM_TYPE_MQ_REQUEST_BASED: | |
3269 | cachep = _rq_tio_cache; | |
3270 | if (!pool_size) | |
3271 | pool_size = dm_get_reserved_rq_based_ios(); | |
5f015204 JN |
3272 | front_pad = offsetof(struct dm_rq_clone_bio_info, clone); |
3273 | /* per_bio_data_size is not used. See __bind_mempools(). */ | |
3274 | WARN_ON(per_bio_data_size != 0); | |
e5863d9a MS |
3275 | break; |
3276 | default: | |
5f015204 | 3277 | goto out; |
e5863d9a | 3278 | } |
e6ee8c0b | 3279 | |
6cfa5857 | 3280 | pools->io_pool = mempool_create_slab_pool(pool_size, cachep); |
5f015204 JN |
3281 | if (!pools->io_pool) |
3282 | goto out; | |
e6ee8c0b | 3283 | |
3d8aab2d | 3284 | pools->bs = bioset_create_nobvec(pool_size, front_pad); |
e6ee8c0b | 3285 | if (!pools->bs) |
5f015204 | 3286 | goto out; |
e6ee8c0b | 3287 | |
a91a2785 | 3288 | if (integrity && bioset_integrity_create(pools->bs, pool_size)) |
5f015204 | 3289 | goto out; |
a91a2785 | 3290 | |
e6ee8c0b KU |
3291 | return pools; |
3292 | ||
5f015204 JN |
3293 | out: |
3294 | dm_free_md_mempools(pools); | |
e6ee8c0b KU |
3295 | |
3296 | return NULL; | |
3297 | } | |
3298 | ||
3299 | void dm_free_md_mempools(struct dm_md_mempools *pools) | |
3300 | { | |
3301 | if (!pools) | |
3302 | return; | |
3303 | ||
3304 | if (pools->io_pool) | |
3305 | mempool_destroy(pools->io_pool); | |
3306 | ||
1ae49ea2 MS |
3307 | if (pools->rq_pool) |
3308 | mempool_destroy(pools->rq_pool); | |
3309 | ||
e6ee8c0b KU |
3310 | if (pools->bs) |
3311 | bioset_free(pools->bs); | |
3312 | ||
3313 | kfree(pools); | |
3314 | } | |
3315 | ||
83d5cde4 | 3316 | static const struct block_device_operations dm_blk_dops = { |
1da177e4 LT |
3317 | .open = dm_blk_open, |
3318 | .release = dm_blk_close, | |
aa129a22 | 3319 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 3320 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
3321 | .owner = THIS_MODULE |
3322 | }; | |
3323 | ||
1da177e4 LT |
3324 | /* |
3325 | * module hooks | |
3326 | */ | |
3327 | module_init(dm_init); | |
3328 | module_exit(dm_exit); | |
3329 | ||
3330 | module_param(major, uint, 0); | |
3331 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
f4790826 | 3332 | |
e8603136 MS |
3333 | module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR); |
3334 | MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools"); | |
3335 | ||
f4790826 MS |
3336 | module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR); |
3337 | MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools"); | |
3338 | ||
1da177e4 LT |
3339 | MODULE_DESCRIPTION(DM_NAME " driver"); |
3340 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
3341 | MODULE_LICENSE("GPL"); |