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> |
0ce65797 | 24 | #include <linux/ktime.h> |
de3ec86d | 25 | #include <linux/elevator.h> /* for rq_end_sector() */ |
55782138 LZ |
26 | |
27 | #include <trace/events/block.h> | |
1da177e4 | 28 | |
72d94861 AK |
29 | #define DM_MSG_PREFIX "core" |
30 | ||
71a16736 NK |
31 | #ifdef CONFIG_PRINTK |
32 | /* | |
33 | * ratelimit state to be used in DMXXX_LIMIT(). | |
34 | */ | |
35 | DEFINE_RATELIMIT_STATE(dm_ratelimit_state, | |
36 | DEFAULT_RATELIMIT_INTERVAL, | |
37 | DEFAULT_RATELIMIT_BURST); | |
38 | EXPORT_SYMBOL(dm_ratelimit_state); | |
39 | #endif | |
40 | ||
60935eb2 MB |
41 | /* |
42 | * Cookies are numeric values sent with CHANGE and REMOVE | |
43 | * uevents while resuming, removing or renaming the device. | |
44 | */ | |
45 | #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" | |
46 | #define DM_COOKIE_LENGTH 24 | |
47 | ||
1da177e4 LT |
48 | static const char *_name = DM_NAME; |
49 | ||
50 | static unsigned int major = 0; | |
51 | static unsigned int _major = 0; | |
52 | ||
d15b774c AK |
53 | static DEFINE_IDR(_minor_idr); |
54 | ||
f32c10b0 | 55 | static DEFINE_SPINLOCK(_minor_lock); |
2c140a24 MP |
56 | |
57 | static void do_deferred_remove(struct work_struct *w); | |
58 | ||
59 | static DECLARE_WORK(deferred_remove_work, do_deferred_remove); | |
60 | ||
acfe0ad7 MP |
61 | static struct workqueue_struct *deferred_remove_workqueue; |
62 | ||
1da177e4 | 63 | /* |
8fbf26ad | 64 | * For bio-based dm. |
1da177e4 LT |
65 | * One of these is allocated per bio. |
66 | */ | |
67 | struct dm_io { | |
68 | struct mapped_device *md; | |
69 | int error; | |
1da177e4 | 70 | atomic_t io_count; |
6ae2fa67 | 71 | struct bio *bio; |
3eaf840e | 72 | unsigned long start_time; |
f88fb981 | 73 | spinlock_t endio_lock; |
fd2ed4d2 | 74 | struct dm_stats_aux stats_aux; |
1da177e4 LT |
75 | }; |
76 | ||
8fbf26ad KU |
77 | /* |
78 | * For request-based dm. | |
79 | * One of these is allocated per request. | |
80 | */ | |
81 | struct dm_rq_target_io { | |
82 | struct mapped_device *md; | |
83 | struct dm_target *ti; | |
1ae49ea2 | 84 | struct request *orig, *clone; |
2eb6e1e3 | 85 | struct kthread_work work; |
8fbf26ad KU |
86 | int error; |
87 | union map_info info; | |
88 | }; | |
89 | ||
90 | /* | |
94818742 KO |
91 | * For request-based dm - the bio clones we allocate are embedded in these |
92 | * structs. | |
93 | * | |
94 | * We allocate these with bio_alloc_bioset, using the front_pad parameter when | |
95 | * the bioset is created - this means the bio has to come at the end of the | |
96 | * struct. | |
8fbf26ad KU |
97 | */ |
98 | struct dm_rq_clone_bio_info { | |
99 | struct bio *orig; | |
cec47e3d | 100 | struct dm_rq_target_io *tio; |
94818742 | 101 | struct bio clone; |
8fbf26ad KU |
102 | }; |
103 | ||
cec47e3d KU |
104 | union map_info *dm_get_rq_mapinfo(struct request *rq) |
105 | { | |
106 | if (rq && rq->end_io_data) | |
107 | return &((struct dm_rq_target_io *)rq->end_io_data)->info; | |
108 | return NULL; | |
109 | } | |
110 | EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo); | |
111 | ||
ba61fdd1 JM |
112 | #define MINOR_ALLOCED ((void *)-1) |
113 | ||
1da177e4 LT |
114 | /* |
115 | * Bits for the md->flags field. | |
116 | */ | |
1eb787ec | 117 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
1da177e4 | 118 | #define DMF_SUSPENDED 1 |
aa8d7c2f | 119 | #define DMF_FROZEN 2 |
fba9f90e | 120 | #define DMF_FREEING 3 |
5c6bd75d | 121 | #define DMF_DELETING 4 |
2e93ccc1 | 122 | #define DMF_NOFLUSH_SUSPENDING 5 |
d5b9dd04 | 123 | #define DMF_MERGE_IS_OPTIONAL 6 |
2c140a24 | 124 | #define DMF_DEFERRED_REMOVE 7 |
ffcc3936 | 125 | #define DMF_SUSPENDED_INTERNALLY 8 |
1da177e4 | 126 | |
83d5e5b0 MP |
127 | /* |
128 | * A dummy definition to make RCU happy. | |
129 | * struct dm_table should never be dereferenced in this file. | |
130 | */ | |
131 | struct dm_table { | |
132 | int undefined__; | |
133 | }; | |
134 | ||
304f3f6a MB |
135 | /* |
136 | * Work processed by per-device workqueue. | |
137 | */ | |
1da177e4 | 138 | struct mapped_device { |
83d5e5b0 | 139 | struct srcu_struct io_barrier; |
e61290a4 | 140 | struct mutex suspend_lock; |
1da177e4 | 141 | atomic_t holders; |
5c6bd75d | 142 | atomic_t open_count; |
1da177e4 | 143 | |
2a7faeb1 MP |
144 | /* |
145 | * The current mapping. | |
146 | * Use dm_get_live_table{_fast} or take suspend_lock for | |
147 | * dereference. | |
148 | */ | |
6fa99520 | 149 | struct dm_table __rcu *map; |
2a7faeb1 | 150 | |
86f1152b BM |
151 | struct list_head table_devices; |
152 | struct mutex table_devices_lock; | |
153 | ||
1da177e4 LT |
154 | unsigned long flags; |
155 | ||
165125e1 | 156 | struct request_queue *queue; |
a5664dad | 157 | unsigned type; |
4a0b4ddf | 158 | /* Protect queue and type against concurrent access. */ |
a5664dad MS |
159 | struct mutex type_lock; |
160 | ||
36a0456f AK |
161 | struct target_type *immutable_target_type; |
162 | ||
1da177e4 | 163 | struct gendisk *disk; |
7e51f257 | 164 | char name[16]; |
1da177e4 LT |
165 | |
166 | void *interface_ptr; | |
167 | ||
168 | /* | |
169 | * A list of ios that arrived while we were suspended. | |
170 | */ | |
316d315b | 171 | atomic_t pending[2]; |
1da177e4 | 172 | wait_queue_head_t wait; |
53d5914f | 173 | struct work_struct work; |
74859364 | 174 | struct bio_list deferred; |
022c2611 | 175 | spinlock_t deferred_lock; |
1da177e4 | 176 | |
af7e466a | 177 | /* |
29e4013d | 178 | * Processing queue (flush) |
304f3f6a MB |
179 | */ |
180 | struct workqueue_struct *wq; | |
181 | ||
1da177e4 LT |
182 | /* |
183 | * io objects are allocated from here. | |
184 | */ | |
185 | mempool_t *io_pool; | |
1ae49ea2 | 186 | mempool_t *rq_pool; |
1da177e4 | 187 | |
9faf400f SB |
188 | struct bio_set *bs; |
189 | ||
1da177e4 LT |
190 | /* |
191 | * Event handling. | |
192 | */ | |
193 | atomic_t event_nr; | |
194 | wait_queue_head_t eventq; | |
7a8c3d3b MA |
195 | atomic_t uevent_seq; |
196 | struct list_head uevent_list; | |
197 | spinlock_t uevent_lock; /* Protect access to uevent_list */ | |
1da177e4 LT |
198 | |
199 | /* | |
200 | * freeze/thaw support require holding onto a super block | |
201 | */ | |
202 | struct super_block *frozen_sb; | |
db8fef4f | 203 | struct block_device *bdev; |
3ac51e74 DW |
204 | |
205 | /* forced geometry settings */ | |
206 | struct hd_geometry geometry; | |
784aae73 | 207 | |
2995fa78 MP |
208 | /* kobject and completion */ |
209 | struct dm_kobject_holder kobj_holder; | |
be35f486 | 210 | |
d87f4c14 TH |
211 | /* zero-length flush that will be cloned and submitted to targets */ |
212 | struct bio flush_bio; | |
fd2ed4d2 | 213 | |
96b26c8c MP |
214 | /* the number of internal suspends */ |
215 | unsigned internal_suspend_count; | |
216 | ||
fd2ed4d2 | 217 | struct dm_stats stats; |
2eb6e1e3 KB |
218 | |
219 | struct kthread_worker kworker; | |
220 | struct task_struct *kworker_task; | |
de3ec86d MS |
221 | |
222 | /* for request-based merge heuristic in dm_request_fn() */ | |
0ce65797 | 223 | unsigned seq_rq_merge_deadline_usecs; |
de3ec86d | 224 | int last_rq_rw; |
0ce65797 MS |
225 | sector_t last_rq_pos; |
226 | ktime_t last_rq_start_time; | |
1da177e4 LT |
227 | }; |
228 | ||
e6ee8c0b KU |
229 | /* |
230 | * For mempools pre-allocation at the table loading time. | |
231 | */ | |
232 | struct dm_md_mempools { | |
233 | mempool_t *io_pool; | |
1ae49ea2 | 234 | mempool_t *rq_pool; |
e6ee8c0b KU |
235 | struct bio_set *bs; |
236 | }; | |
237 | ||
86f1152b BM |
238 | struct table_device { |
239 | struct list_head list; | |
240 | atomic_t count; | |
241 | struct dm_dev dm_dev; | |
242 | }; | |
243 | ||
6cfa5857 MS |
244 | #define RESERVED_BIO_BASED_IOS 16 |
245 | #define RESERVED_REQUEST_BASED_IOS 256 | |
f4790826 | 246 | #define RESERVED_MAX_IOS 1024 |
e18b890b | 247 | static struct kmem_cache *_io_cache; |
8fbf26ad | 248 | static struct kmem_cache *_rq_tio_cache; |
1ae49ea2 | 249 | static struct kmem_cache *_rq_cache; |
94818742 | 250 | |
e8603136 MS |
251 | /* |
252 | * Bio-based DM's mempools' reserved IOs set by the user. | |
253 | */ | |
254 | static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; | |
255 | ||
f4790826 MS |
256 | /* |
257 | * Request-based DM's mempools' reserved IOs set by the user. | |
258 | */ | |
259 | static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS; | |
260 | ||
09c2d531 | 261 | static unsigned __dm_get_module_param(unsigned *module_param, |
f4790826 MS |
262 | unsigned def, unsigned max) |
263 | { | |
09c2d531 MS |
264 | unsigned param = ACCESS_ONCE(*module_param); |
265 | unsigned modified_param = 0; | |
f4790826 | 266 | |
09c2d531 MS |
267 | if (!param) |
268 | modified_param = def; | |
269 | else if (param > max) | |
270 | modified_param = max; | |
f4790826 | 271 | |
09c2d531 MS |
272 | if (modified_param) { |
273 | (void)cmpxchg(module_param, param, modified_param); | |
274 | param = modified_param; | |
f4790826 MS |
275 | } |
276 | ||
09c2d531 | 277 | return param; |
f4790826 MS |
278 | } |
279 | ||
e8603136 MS |
280 | unsigned dm_get_reserved_bio_based_ios(void) |
281 | { | |
09c2d531 | 282 | return __dm_get_module_param(&reserved_bio_based_ios, |
e8603136 MS |
283 | RESERVED_BIO_BASED_IOS, RESERVED_MAX_IOS); |
284 | } | |
285 | EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); | |
286 | ||
f4790826 MS |
287 | unsigned dm_get_reserved_rq_based_ios(void) |
288 | { | |
09c2d531 | 289 | return __dm_get_module_param(&reserved_rq_based_ios, |
f4790826 MS |
290 | RESERVED_REQUEST_BASED_IOS, RESERVED_MAX_IOS); |
291 | } | |
292 | EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios); | |
293 | ||
1da177e4 LT |
294 | static int __init local_init(void) |
295 | { | |
51157b4a | 296 | int r = -ENOMEM; |
1da177e4 | 297 | |
1da177e4 | 298 | /* allocate a slab for the dm_ios */ |
028867ac | 299 | _io_cache = KMEM_CACHE(dm_io, 0); |
1da177e4 | 300 | if (!_io_cache) |
51157b4a | 301 | return r; |
1da177e4 | 302 | |
8fbf26ad KU |
303 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
304 | if (!_rq_tio_cache) | |
dba14160 | 305 | goto out_free_io_cache; |
8fbf26ad | 306 | |
1ae49ea2 MS |
307 | _rq_cache = kmem_cache_create("dm_clone_request", sizeof(struct request), |
308 | __alignof__(struct request), 0, NULL); | |
309 | if (!_rq_cache) | |
310 | goto out_free_rq_tio_cache; | |
311 | ||
51e5b2bd | 312 | r = dm_uevent_init(); |
51157b4a | 313 | if (r) |
1ae49ea2 | 314 | goto out_free_rq_cache; |
51e5b2bd | 315 | |
acfe0ad7 MP |
316 | deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1); |
317 | if (!deferred_remove_workqueue) { | |
318 | r = -ENOMEM; | |
319 | goto out_uevent_exit; | |
320 | } | |
321 | ||
1da177e4 LT |
322 | _major = major; |
323 | r = register_blkdev(_major, _name); | |
51157b4a | 324 | if (r < 0) |
acfe0ad7 | 325 | goto out_free_workqueue; |
1da177e4 LT |
326 | |
327 | if (!_major) | |
328 | _major = r; | |
329 | ||
330 | return 0; | |
51157b4a | 331 | |
acfe0ad7 MP |
332 | out_free_workqueue: |
333 | destroy_workqueue(deferred_remove_workqueue); | |
51157b4a KU |
334 | out_uevent_exit: |
335 | dm_uevent_exit(); | |
1ae49ea2 MS |
336 | out_free_rq_cache: |
337 | kmem_cache_destroy(_rq_cache); | |
8fbf26ad KU |
338 | out_free_rq_tio_cache: |
339 | kmem_cache_destroy(_rq_tio_cache); | |
51157b4a KU |
340 | out_free_io_cache: |
341 | kmem_cache_destroy(_io_cache); | |
342 | ||
343 | return r; | |
1da177e4 LT |
344 | } |
345 | ||
346 | static void local_exit(void) | |
347 | { | |
2c140a24 | 348 | flush_scheduled_work(); |
acfe0ad7 | 349 | destroy_workqueue(deferred_remove_workqueue); |
2c140a24 | 350 | |
1ae49ea2 | 351 | kmem_cache_destroy(_rq_cache); |
8fbf26ad | 352 | kmem_cache_destroy(_rq_tio_cache); |
1da177e4 | 353 | kmem_cache_destroy(_io_cache); |
00d59405 | 354 | unregister_blkdev(_major, _name); |
51e5b2bd | 355 | dm_uevent_exit(); |
1da177e4 LT |
356 | |
357 | _major = 0; | |
358 | ||
359 | DMINFO("cleaned up"); | |
360 | } | |
361 | ||
b9249e55 | 362 | static int (*_inits[])(void) __initdata = { |
1da177e4 LT |
363 | local_init, |
364 | dm_target_init, | |
365 | dm_linear_init, | |
366 | dm_stripe_init, | |
952b3557 | 367 | dm_io_init, |
945fa4d2 | 368 | dm_kcopyd_init, |
1da177e4 | 369 | dm_interface_init, |
fd2ed4d2 | 370 | dm_statistics_init, |
1da177e4 LT |
371 | }; |
372 | ||
b9249e55 | 373 | static void (*_exits[])(void) = { |
1da177e4 LT |
374 | local_exit, |
375 | dm_target_exit, | |
376 | dm_linear_exit, | |
377 | dm_stripe_exit, | |
952b3557 | 378 | dm_io_exit, |
945fa4d2 | 379 | dm_kcopyd_exit, |
1da177e4 | 380 | dm_interface_exit, |
fd2ed4d2 | 381 | dm_statistics_exit, |
1da177e4 LT |
382 | }; |
383 | ||
384 | static int __init dm_init(void) | |
385 | { | |
386 | const int count = ARRAY_SIZE(_inits); | |
387 | ||
388 | int r, i; | |
389 | ||
390 | for (i = 0; i < count; i++) { | |
391 | r = _inits[i](); | |
392 | if (r) | |
393 | goto bad; | |
394 | } | |
395 | ||
396 | return 0; | |
397 | ||
398 | bad: | |
399 | while (i--) | |
400 | _exits[i](); | |
401 | ||
402 | return r; | |
403 | } | |
404 | ||
405 | static void __exit dm_exit(void) | |
406 | { | |
407 | int i = ARRAY_SIZE(_exits); | |
408 | ||
409 | while (i--) | |
410 | _exits[i](); | |
d15b774c AK |
411 | |
412 | /* | |
413 | * Should be empty by this point. | |
414 | */ | |
d15b774c | 415 | idr_destroy(&_minor_idr); |
1da177e4 LT |
416 | } |
417 | ||
418 | /* | |
419 | * Block device functions | |
420 | */ | |
432a212c MA |
421 | int dm_deleting_md(struct mapped_device *md) |
422 | { | |
423 | return test_bit(DMF_DELETING, &md->flags); | |
424 | } | |
425 | ||
fe5f9f2c | 426 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
427 | { |
428 | struct mapped_device *md; | |
429 | ||
fba9f90e JM |
430 | spin_lock(&_minor_lock); |
431 | ||
fe5f9f2c | 432 | md = bdev->bd_disk->private_data; |
fba9f90e JM |
433 | if (!md) |
434 | goto out; | |
435 | ||
5c6bd75d | 436 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 437 | dm_deleting_md(md)) { |
fba9f90e JM |
438 | md = NULL; |
439 | goto out; | |
440 | } | |
441 | ||
1da177e4 | 442 | dm_get(md); |
5c6bd75d | 443 | atomic_inc(&md->open_count); |
fba9f90e JM |
444 | out: |
445 | spin_unlock(&_minor_lock); | |
446 | ||
447 | return md ? 0 : -ENXIO; | |
1da177e4 LT |
448 | } |
449 | ||
db2a144b | 450 | static void dm_blk_close(struct gendisk *disk, fmode_t mode) |
1da177e4 | 451 | { |
63a4f065 | 452 | struct mapped_device *md; |
6e9624b8 | 453 | |
4a1aeb98 MB |
454 | spin_lock(&_minor_lock); |
455 | ||
63a4f065 MS |
456 | md = disk->private_data; |
457 | if (WARN_ON(!md)) | |
458 | goto out; | |
459 | ||
2c140a24 MP |
460 | if (atomic_dec_and_test(&md->open_count) && |
461 | (test_bit(DMF_DEFERRED_REMOVE, &md->flags))) | |
acfe0ad7 | 462 | queue_work(deferred_remove_workqueue, &deferred_remove_work); |
2c140a24 | 463 | |
1da177e4 | 464 | dm_put(md); |
63a4f065 | 465 | out: |
4a1aeb98 | 466 | spin_unlock(&_minor_lock); |
1da177e4 LT |
467 | } |
468 | ||
5c6bd75d AK |
469 | int dm_open_count(struct mapped_device *md) |
470 | { | |
471 | return atomic_read(&md->open_count); | |
472 | } | |
473 | ||
474 | /* | |
475 | * Guarantees nothing is using the device before it's deleted. | |
476 | */ | |
2c140a24 | 477 | int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred) |
5c6bd75d AK |
478 | { |
479 | int r = 0; | |
480 | ||
481 | spin_lock(&_minor_lock); | |
482 | ||
2c140a24 | 483 | if (dm_open_count(md)) { |
5c6bd75d | 484 | r = -EBUSY; |
2c140a24 MP |
485 | if (mark_deferred) |
486 | set_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
487 | } else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags)) | |
488 | r = -EEXIST; | |
5c6bd75d AK |
489 | else |
490 | set_bit(DMF_DELETING, &md->flags); | |
491 | ||
492 | spin_unlock(&_minor_lock); | |
493 | ||
494 | return r; | |
495 | } | |
496 | ||
2c140a24 MP |
497 | int dm_cancel_deferred_remove(struct mapped_device *md) |
498 | { | |
499 | int r = 0; | |
500 | ||
501 | spin_lock(&_minor_lock); | |
502 | ||
503 | if (test_bit(DMF_DELETING, &md->flags)) | |
504 | r = -EBUSY; | |
505 | else | |
506 | clear_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
507 | ||
508 | spin_unlock(&_minor_lock); | |
509 | ||
510 | return r; | |
511 | } | |
512 | ||
513 | static void do_deferred_remove(struct work_struct *w) | |
514 | { | |
515 | dm_deferred_remove(); | |
516 | } | |
517 | ||
fd2ed4d2 MP |
518 | sector_t dm_get_size(struct mapped_device *md) |
519 | { | |
520 | return get_capacity(md->disk); | |
521 | } | |
522 | ||
9974fa2c MS |
523 | struct request_queue *dm_get_md_queue(struct mapped_device *md) |
524 | { | |
525 | return md->queue; | |
526 | } | |
527 | ||
fd2ed4d2 MP |
528 | struct dm_stats *dm_get_stats(struct mapped_device *md) |
529 | { | |
530 | return &md->stats; | |
531 | } | |
532 | ||
3ac51e74 DW |
533 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
534 | { | |
535 | struct mapped_device *md = bdev->bd_disk->private_data; | |
536 | ||
537 | return dm_get_geometry(md, geo); | |
538 | } | |
539 | ||
fe5f9f2c | 540 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
aa129a22 MB |
541 | unsigned int cmd, unsigned long arg) |
542 | { | |
fe5f9f2c | 543 | struct mapped_device *md = bdev->bd_disk->private_data; |
83d5e5b0 | 544 | int srcu_idx; |
6c182cd8 | 545 | struct dm_table *map; |
aa129a22 MB |
546 | struct dm_target *tgt; |
547 | int r = -ENOTTY; | |
548 | ||
6c182cd8 | 549 | retry: |
83d5e5b0 MP |
550 | map = dm_get_live_table(md, &srcu_idx); |
551 | ||
aa129a22 MB |
552 | if (!map || !dm_table_get_size(map)) |
553 | goto out; | |
554 | ||
555 | /* We only support devices that have a single target */ | |
556 | if (dm_table_get_num_targets(map) != 1) | |
557 | goto out; | |
558 | ||
559 | tgt = dm_table_get_target(map, 0); | |
4d341d82 MS |
560 | if (!tgt->type->ioctl) |
561 | goto out; | |
aa129a22 | 562 | |
4f186f8b | 563 | if (dm_suspended_md(md)) { |
aa129a22 MB |
564 | r = -EAGAIN; |
565 | goto out; | |
566 | } | |
567 | ||
4d341d82 | 568 | r = tgt->type->ioctl(tgt, cmd, arg); |
aa129a22 MB |
569 | |
570 | out: | |
83d5e5b0 | 571 | dm_put_live_table(md, srcu_idx); |
aa129a22 | 572 | |
6c182cd8 HR |
573 | if (r == -ENOTCONN) { |
574 | msleep(10); | |
575 | goto retry; | |
576 | } | |
577 | ||
aa129a22 MB |
578 | return r; |
579 | } | |
580 | ||
028867ac | 581 | static struct dm_io *alloc_io(struct mapped_device *md) |
1da177e4 LT |
582 | { |
583 | return mempool_alloc(md->io_pool, GFP_NOIO); | |
584 | } | |
585 | ||
028867ac | 586 | static void free_io(struct mapped_device *md, struct dm_io *io) |
1da177e4 LT |
587 | { |
588 | mempool_free(io, md->io_pool); | |
589 | } | |
590 | ||
028867ac | 591 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
1da177e4 | 592 | { |
dba14160 | 593 | bio_put(&tio->clone); |
1da177e4 LT |
594 | } |
595 | ||
08885643 KU |
596 | static struct dm_rq_target_io *alloc_rq_tio(struct mapped_device *md, |
597 | gfp_t gfp_mask) | |
cec47e3d | 598 | { |
5f015204 | 599 | return mempool_alloc(md->io_pool, gfp_mask); |
cec47e3d KU |
600 | } |
601 | ||
602 | static void free_rq_tio(struct dm_rq_target_io *tio) | |
603 | { | |
5f015204 | 604 | mempool_free(tio, tio->md->io_pool); |
cec47e3d KU |
605 | } |
606 | ||
1ae49ea2 MS |
607 | static struct request *alloc_clone_request(struct mapped_device *md, |
608 | gfp_t gfp_mask) | |
609 | { | |
610 | return mempool_alloc(md->rq_pool, gfp_mask); | |
611 | } | |
612 | ||
613 | static void free_clone_request(struct mapped_device *md, struct request *rq) | |
614 | { | |
615 | mempool_free(rq, md->rq_pool); | |
616 | } | |
617 | ||
90abb8c4 KU |
618 | static int md_in_flight(struct mapped_device *md) |
619 | { | |
620 | return atomic_read(&md->pending[READ]) + | |
621 | atomic_read(&md->pending[WRITE]); | |
622 | } | |
623 | ||
3eaf840e JNN |
624 | static void start_io_acct(struct dm_io *io) |
625 | { | |
626 | struct mapped_device *md = io->md; | |
fd2ed4d2 | 627 | struct bio *bio = io->bio; |
c9959059 | 628 | int cpu; |
fd2ed4d2 | 629 | int rw = bio_data_dir(bio); |
3eaf840e JNN |
630 | |
631 | io->start_time = jiffies; | |
632 | ||
074a7aca TH |
633 | cpu = part_stat_lock(); |
634 | part_round_stats(cpu, &dm_disk(md)->part0); | |
635 | part_stat_unlock(); | |
1e9bb880 SL |
636 | atomic_set(&dm_disk(md)->part0.in_flight[rw], |
637 | atomic_inc_return(&md->pending[rw])); | |
fd2ed4d2 MP |
638 | |
639 | if (unlikely(dm_stats_used(&md->stats))) | |
4f024f37 | 640 | dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, |
fd2ed4d2 | 641 | bio_sectors(bio), false, 0, &io->stats_aux); |
3eaf840e JNN |
642 | } |
643 | ||
d221d2e7 | 644 | static void end_io_acct(struct dm_io *io) |
3eaf840e JNN |
645 | { |
646 | struct mapped_device *md = io->md; | |
647 | struct bio *bio = io->bio; | |
648 | unsigned long duration = jiffies - io->start_time; | |
18c0b223 | 649 | int pending; |
3eaf840e JNN |
650 | int rw = bio_data_dir(bio); |
651 | ||
18c0b223 | 652 | generic_end_io_acct(rw, &dm_disk(md)->part0, io->start_time); |
3eaf840e | 653 | |
fd2ed4d2 | 654 | if (unlikely(dm_stats_used(&md->stats))) |
4f024f37 | 655 | dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, |
fd2ed4d2 MP |
656 | bio_sectors(bio), true, duration, &io->stats_aux); |
657 | ||
af7e466a MP |
658 | /* |
659 | * After this is decremented the bio must not be touched if it is | |
d87f4c14 | 660 | * a flush. |
af7e466a | 661 | */ |
1e9bb880 SL |
662 | pending = atomic_dec_return(&md->pending[rw]); |
663 | atomic_set(&dm_disk(md)->part0.in_flight[rw], pending); | |
316d315b | 664 | pending += atomic_read(&md->pending[rw^0x1]); |
3eaf840e | 665 | |
d221d2e7 MP |
666 | /* nudge anyone waiting on suspend queue */ |
667 | if (!pending) | |
668 | wake_up(&md->wait); | |
3eaf840e JNN |
669 | } |
670 | ||
1da177e4 LT |
671 | /* |
672 | * Add the bio to the list of deferred io. | |
673 | */ | |
92c63902 | 674 | static void queue_io(struct mapped_device *md, struct bio *bio) |
1da177e4 | 675 | { |
05447420 | 676 | unsigned long flags; |
1da177e4 | 677 | |
05447420 | 678 | spin_lock_irqsave(&md->deferred_lock, flags); |
1da177e4 | 679 | bio_list_add(&md->deferred, bio); |
05447420 | 680 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
6a8736d1 | 681 | queue_work(md->wq, &md->work); |
1da177e4 LT |
682 | } |
683 | ||
684 | /* | |
685 | * Everyone (including functions in this file), should use this | |
686 | * function to access the md->map field, and make sure they call | |
83d5e5b0 | 687 | * dm_put_live_table() when finished. |
1da177e4 | 688 | */ |
83d5e5b0 | 689 | struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier) |
1da177e4 | 690 | { |
83d5e5b0 MP |
691 | *srcu_idx = srcu_read_lock(&md->io_barrier); |
692 | ||
693 | return srcu_dereference(md->map, &md->io_barrier); | |
694 | } | |
1da177e4 | 695 | |
83d5e5b0 MP |
696 | void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier) |
697 | { | |
698 | srcu_read_unlock(&md->io_barrier, srcu_idx); | |
699 | } | |
700 | ||
701 | void dm_sync_table(struct mapped_device *md) | |
702 | { | |
703 | synchronize_srcu(&md->io_barrier); | |
704 | synchronize_rcu_expedited(); | |
705 | } | |
706 | ||
707 | /* | |
708 | * A fast alternative to dm_get_live_table/dm_put_live_table. | |
709 | * The caller must not block between these two functions. | |
710 | */ | |
711 | static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU) | |
712 | { | |
713 | rcu_read_lock(); | |
714 | return rcu_dereference(md->map); | |
715 | } | |
1da177e4 | 716 | |
83d5e5b0 MP |
717 | static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU) |
718 | { | |
719 | rcu_read_unlock(); | |
1da177e4 LT |
720 | } |
721 | ||
86f1152b BM |
722 | /* |
723 | * Open a table device so we can use it as a map destination. | |
724 | */ | |
725 | static int open_table_device(struct table_device *td, dev_t dev, | |
726 | struct mapped_device *md) | |
727 | { | |
728 | static char *_claim_ptr = "I belong to device-mapper"; | |
729 | struct block_device *bdev; | |
730 | ||
731 | int r; | |
732 | ||
733 | BUG_ON(td->dm_dev.bdev); | |
734 | ||
735 | bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _claim_ptr); | |
736 | if (IS_ERR(bdev)) | |
737 | return PTR_ERR(bdev); | |
738 | ||
739 | r = bd_link_disk_holder(bdev, dm_disk(md)); | |
740 | if (r) { | |
741 | blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL); | |
742 | return r; | |
743 | } | |
744 | ||
745 | td->dm_dev.bdev = bdev; | |
746 | return 0; | |
747 | } | |
748 | ||
749 | /* | |
750 | * Close a table device that we've been using. | |
751 | */ | |
752 | static void close_table_device(struct table_device *td, struct mapped_device *md) | |
753 | { | |
754 | if (!td->dm_dev.bdev) | |
755 | return; | |
756 | ||
757 | bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md)); | |
758 | blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL); | |
759 | td->dm_dev.bdev = NULL; | |
760 | } | |
761 | ||
762 | static struct table_device *find_table_device(struct list_head *l, dev_t dev, | |
763 | fmode_t mode) { | |
764 | struct table_device *td; | |
765 | ||
766 | list_for_each_entry(td, l, list) | |
767 | if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode) | |
768 | return td; | |
769 | ||
770 | return NULL; | |
771 | } | |
772 | ||
773 | int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, | |
774 | struct dm_dev **result) { | |
775 | int r; | |
776 | struct table_device *td; | |
777 | ||
778 | mutex_lock(&md->table_devices_lock); | |
779 | td = find_table_device(&md->table_devices, dev, mode); | |
780 | if (!td) { | |
781 | td = kmalloc(sizeof(*td), GFP_KERNEL); | |
782 | if (!td) { | |
783 | mutex_unlock(&md->table_devices_lock); | |
784 | return -ENOMEM; | |
785 | } | |
786 | ||
787 | td->dm_dev.mode = mode; | |
788 | td->dm_dev.bdev = NULL; | |
789 | ||
790 | if ((r = open_table_device(td, dev, md))) { | |
791 | mutex_unlock(&md->table_devices_lock); | |
792 | kfree(td); | |
793 | return r; | |
794 | } | |
795 | ||
796 | format_dev_t(td->dm_dev.name, dev); | |
797 | ||
798 | atomic_set(&td->count, 0); | |
799 | list_add(&td->list, &md->table_devices); | |
800 | } | |
801 | atomic_inc(&td->count); | |
802 | mutex_unlock(&md->table_devices_lock); | |
803 | ||
804 | *result = &td->dm_dev; | |
805 | return 0; | |
806 | } | |
807 | EXPORT_SYMBOL_GPL(dm_get_table_device); | |
808 | ||
809 | void dm_put_table_device(struct mapped_device *md, struct dm_dev *d) | |
810 | { | |
811 | struct table_device *td = container_of(d, struct table_device, dm_dev); | |
812 | ||
813 | mutex_lock(&md->table_devices_lock); | |
814 | if (atomic_dec_and_test(&td->count)) { | |
815 | close_table_device(td, md); | |
816 | list_del(&td->list); | |
817 | kfree(td); | |
818 | } | |
819 | mutex_unlock(&md->table_devices_lock); | |
820 | } | |
821 | EXPORT_SYMBOL(dm_put_table_device); | |
822 | ||
823 | static void free_table_devices(struct list_head *devices) | |
824 | { | |
825 | struct list_head *tmp, *next; | |
826 | ||
827 | list_for_each_safe(tmp, next, devices) { | |
828 | struct table_device *td = list_entry(tmp, struct table_device, list); | |
829 | ||
830 | DMWARN("dm_destroy: %s still exists with %d references", | |
831 | td->dm_dev.name, atomic_read(&td->count)); | |
832 | kfree(td); | |
833 | } | |
834 | } | |
835 | ||
3ac51e74 DW |
836 | /* |
837 | * Get the geometry associated with a dm device | |
838 | */ | |
839 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
840 | { | |
841 | *geo = md->geometry; | |
842 | ||
843 | return 0; | |
844 | } | |
845 | ||
846 | /* | |
847 | * Set the geometry of a device. | |
848 | */ | |
849 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
850 | { | |
851 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
852 | ||
853 | if (geo->start > sz) { | |
854 | DMWARN("Start sector is beyond the geometry limits."); | |
855 | return -EINVAL; | |
856 | } | |
857 | ||
858 | md->geometry = *geo; | |
859 | ||
860 | return 0; | |
861 | } | |
862 | ||
1da177e4 LT |
863 | /*----------------------------------------------------------------- |
864 | * CRUD START: | |
865 | * A more elegant soln is in the works that uses the queue | |
866 | * merge fn, unfortunately there are a couple of changes to | |
867 | * the block layer that I want to make for this. So in the | |
868 | * interests of getting something for people to use I give | |
869 | * you this clearly demarcated crap. | |
870 | *---------------------------------------------------------------*/ | |
871 | ||
2e93ccc1 KU |
872 | static int __noflush_suspending(struct mapped_device *md) |
873 | { | |
874 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
875 | } | |
876 | ||
1da177e4 LT |
877 | /* |
878 | * Decrements the number of outstanding ios that a bio has been | |
879 | * cloned into, completing the original io if necc. | |
880 | */ | |
858119e1 | 881 | static void dec_pending(struct dm_io *io, int error) |
1da177e4 | 882 | { |
2e93ccc1 | 883 | unsigned long flags; |
b35f8caa MB |
884 | int io_error; |
885 | struct bio *bio; | |
886 | struct mapped_device *md = io->md; | |
2e93ccc1 KU |
887 | |
888 | /* Push-back supersedes any I/O errors */ | |
f88fb981 KU |
889 | if (unlikely(error)) { |
890 | spin_lock_irqsave(&io->endio_lock, flags); | |
891 | if (!(io->error > 0 && __noflush_suspending(md))) | |
892 | io->error = error; | |
893 | spin_unlock_irqrestore(&io->endio_lock, flags); | |
894 | } | |
1da177e4 LT |
895 | |
896 | if (atomic_dec_and_test(&io->io_count)) { | |
2e93ccc1 KU |
897 | if (io->error == DM_ENDIO_REQUEUE) { |
898 | /* | |
899 | * Target requested pushing back the I/O. | |
2e93ccc1 | 900 | */ |
022c2611 | 901 | spin_lock_irqsave(&md->deferred_lock, flags); |
6a8736d1 TH |
902 | if (__noflush_suspending(md)) |
903 | bio_list_add_head(&md->deferred, io->bio); | |
904 | else | |
2e93ccc1 KU |
905 | /* noflush suspend was interrupted. */ |
906 | io->error = -EIO; | |
022c2611 | 907 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
2e93ccc1 KU |
908 | } |
909 | ||
b35f8caa MB |
910 | io_error = io->error; |
911 | bio = io->bio; | |
6a8736d1 TH |
912 | end_io_acct(io); |
913 | free_io(md, io); | |
914 | ||
915 | if (io_error == DM_ENDIO_REQUEUE) | |
916 | return; | |
2e93ccc1 | 917 | |
4f024f37 | 918 | if ((bio->bi_rw & REQ_FLUSH) && bio->bi_iter.bi_size) { |
af7e466a | 919 | /* |
6a8736d1 TH |
920 | * Preflush done for flush with data, reissue |
921 | * without REQ_FLUSH. | |
af7e466a | 922 | */ |
6a8736d1 TH |
923 | bio->bi_rw &= ~REQ_FLUSH; |
924 | queue_io(md, bio); | |
af7e466a | 925 | } else { |
b372d360 | 926 | /* done with normal IO or empty flush */ |
0a82a8d1 | 927 | trace_block_bio_complete(md->queue, bio, io_error); |
b372d360 | 928 | bio_endio(bio, io_error); |
b35f8caa | 929 | } |
1da177e4 LT |
930 | } |
931 | } | |
932 | ||
7eee4ae2 MS |
933 | static void disable_write_same(struct mapped_device *md) |
934 | { | |
935 | struct queue_limits *limits = dm_get_queue_limits(md); | |
936 | ||
937 | /* device doesn't really support WRITE SAME, disable it */ | |
938 | limits->max_write_same_sectors = 0; | |
939 | } | |
940 | ||
6712ecf8 | 941 | static void clone_endio(struct bio *bio, int error) |
1da177e4 | 942 | { |
5164bece | 943 | int r = error; |
bfc6d41c | 944 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
b35f8caa | 945 | struct dm_io *io = tio->io; |
9faf400f | 946 | struct mapped_device *md = tio->io->md; |
1da177e4 LT |
947 | dm_endio_fn endio = tio->ti->type->end_io; |
948 | ||
1da177e4 LT |
949 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
950 | error = -EIO; | |
951 | ||
952 | if (endio) { | |
7de3ee57 | 953 | r = endio(tio->ti, bio, error); |
2e93ccc1 KU |
954 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
955 | /* | |
956 | * error and requeue request are handled | |
957 | * in dec_pending(). | |
958 | */ | |
1da177e4 | 959 | error = r; |
45cbcd79 KU |
960 | else if (r == DM_ENDIO_INCOMPLETE) |
961 | /* The target will handle the io */ | |
6712ecf8 | 962 | return; |
45cbcd79 KU |
963 | else if (r) { |
964 | DMWARN("unimplemented target endio return value: %d", r); | |
965 | BUG(); | |
966 | } | |
1da177e4 LT |
967 | } |
968 | ||
7eee4ae2 MS |
969 | if (unlikely(r == -EREMOTEIO && (bio->bi_rw & REQ_WRITE_SAME) && |
970 | !bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors)) | |
971 | disable_write_same(md); | |
972 | ||
9faf400f | 973 | free_tio(md, tio); |
b35f8caa | 974 | dec_pending(io, error); |
1da177e4 LT |
975 | } |
976 | ||
cec47e3d KU |
977 | /* |
978 | * Partial completion handling for request-based dm | |
979 | */ | |
980 | static void end_clone_bio(struct bio *clone, int error) | |
981 | { | |
bfc6d41c MP |
982 | struct dm_rq_clone_bio_info *info = |
983 | container_of(clone, struct dm_rq_clone_bio_info, clone); | |
cec47e3d KU |
984 | struct dm_rq_target_io *tio = info->tio; |
985 | struct bio *bio = info->orig; | |
4f024f37 | 986 | unsigned int nr_bytes = info->orig->bi_iter.bi_size; |
cec47e3d KU |
987 | |
988 | bio_put(clone); | |
989 | ||
990 | if (tio->error) | |
991 | /* | |
992 | * An error has already been detected on the request. | |
993 | * Once error occurred, just let clone->end_io() handle | |
994 | * the remainder. | |
995 | */ | |
996 | return; | |
997 | else if (error) { | |
998 | /* | |
999 | * Don't notice the error to the upper layer yet. | |
1000 | * The error handling decision is made by the target driver, | |
1001 | * when the request is completed. | |
1002 | */ | |
1003 | tio->error = error; | |
1004 | return; | |
1005 | } | |
1006 | ||
1007 | /* | |
1008 | * I/O for the bio successfully completed. | |
1009 | * Notice the data completion to the upper layer. | |
1010 | */ | |
1011 | ||
1012 | /* | |
1013 | * bios are processed from the head of the list. | |
1014 | * So the completing bio should always be rq->bio. | |
1015 | * If it's not, something wrong is happening. | |
1016 | */ | |
1017 | if (tio->orig->bio != bio) | |
1018 | DMERR("bio completion is going in the middle of the request"); | |
1019 | ||
1020 | /* | |
1021 | * Update the original request. | |
1022 | * Do not use blk_end_request() here, because it may complete | |
1023 | * the original request before the clone, and break the ordering. | |
1024 | */ | |
1025 | blk_update_request(tio->orig, 0, nr_bytes); | |
1026 | } | |
1027 | ||
1028 | /* | |
1029 | * Don't touch any member of the md after calling this function because | |
1030 | * the md may be freed in dm_put() at the end of this function. | |
1031 | * Or do dm_get() before calling this function and dm_put() later. | |
1032 | */ | |
466d89a6 | 1033 | static void rq_completed(struct mapped_device *md, int rw, bool run_queue) |
cec47e3d | 1034 | { |
9a0e609e MS |
1035 | int nr_requests_pending; |
1036 | ||
b4324fee | 1037 | atomic_dec(&md->pending[rw]); |
cec47e3d KU |
1038 | |
1039 | /* nudge anyone waiting on suspend queue */ | |
9a0e609e MS |
1040 | nr_requests_pending = md_in_flight(md); |
1041 | if (!nr_requests_pending) | |
cec47e3d KU |
1042 | wake_up(&md->wait); |
1043 | ||
a8c32a5c JA |
1044 | /* |
1045 | * Run this off this callpath, as drivers could invoke end_io while | |
1046 | * inside their request_fn (and holding the queue lock). Calling | |
1047 | * back into ->request_fn() could deadlock attempting to grab the | |
1048 | * queue lock again. | |
1049 | */ | |
9a0e609e MS |
1050 | if (run_queue) { |
1051 | if (!nr_requests_pending || | |
1052 | (nr_requests_pending >= md->queue->nr_congestion_on)) | |
1053 | blk_run_queue_async(md->queue); | |
1054 | } | |
cec47e3d KU |
1055 | |
1056 | /* | |
1057 | * dm_put() must be at the end of this function. See the comment above | |
1058 | */ | |
1059 | dm_put(md); | |
1060 | } | |
1061 | ||
a77e28c7 KU |
1062 | static void free_rq_clone(struct request *clone) |
1063 | { | |
1064 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1065 | ||
1066 | blk_rq_unprep_clone(clone); | |
e5863d9a MS |
1067 | if (clone->q && clone->q->mq_ops) |
1068 | tio->ti->type->release_clone_rq(clone); | |
1069 | else | |
1070 | free_clone_request(tio->md, clone); | |
a77e28c7 KU |
1071 | free_rq_tio(tio); |
1072 | } | |
1073 | ||
980691e5 KU |
1074 | /* |
1075 | * Complete the clone and the original request. | |
466d89a6 KB |
1076 | * Must be called without clone's queue lock held, |
1077 | * see end_clone_request() for more details. | |
980691e5 KU |
1078 | */ |
1079 | static void dm_end_request(struct request *clone, int error) | |
1080 | { | |
1081 | int rw = rq_data_dir(clone); | |
1082 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1083 | struct mapped_device *md = tio->md; | |
1084 | struct request *rq = tio->orig; | |
1085 | ||
29e4013d | 1086 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
980691e5 KU |
1087 | rq->errors = clone->errors; |
1088 | rq->resid_len = clone->resid_len; | |
1089 | ||
1090 | if (rq->sense) | |
1091 | /* | |
1092 | * We are using the sense buffer of the original | |
1093 | * request. | |
1094 | * So setting the length of the sense data is enough. | |
1095 | */ | |
1096 | rq->sense_len = clone->sense_len; | |
1097 | } | |
1098 | ||
1099 | free_rq_clone(clone); | |
29e4013d TH |
1100 | blk_end_request_all(rq, error); |
1101 | rq_completed(md, rw, true); | |
980691e5 KU |
1102 | } |
1103 | ||
cec47e3d KU |
1104 | static void dm_unprep_request(struct request *rq) |
1105 | { | |
466d89a6 KB |
1106 | struct dm_rq_target_io *tio = rq->special; |
1107 | struct request *clone = tio->clone; | |
cec47e3d KU |
1108 | |
1109 | rq->special = NULL; | |
1110 | rq->cmd_flags &= ~REQ_DONTPREP; | |
1111 | ||
e5863d9a MS |
1112 | if (clone) |
1113 | free_rq_clone(clone); | |
cec47e3d KU |
1114 | } |
1115 | ||
1116 | /* | |
1117 | * Requeue the original request of a clone. | |
1118 | */ | |
466d89a6 KB |
1119 | static void dm_requeue_unmapped_original_request(struct mapped_device *md, |
1120 | struct request *rq) | |
cec47e3d | 1121 | { |
466d89a6 | 1122 | int rw = rq_data_dir(rq); |
cec47e3d KU |
1123 | struct request_queue *q = rq->q; |
1124 | unsigned long flags; | |
1125 | ||
1126 | dm_unprep_request(rq); | |
1127 | ||
1128 | spin_lock_irqsave(q->queue_lock, flags); | |
cec47e3d KU |
1129 | blk_requeue_request(q, rq); |
1130 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1131 | ||
466d89a6 KB |
1132 | rq_completed(md, rw, false); |
1133 | } | |
1134 | ||
1135 | static void dm_requeue_unmapped_request(struct request *clone) | |
1136 | { | |
1137 | struct dm_rq_target_io *tio = clone->end_io_data; | |
1138 | ||
1139 | dm_requeue_unmapped_original_request(tio->md, tio->orig); | |
cec47e3d | 1140 | } |
cec47e3d KU |
1141 | |
1142 | static void __stop_queue(struct request_queue *q) | |
1143 | { | |
1144 | blk_stop_queue(q); | |
1145 | } | |
1146 | ||
1147 | static void stop_queue(struct request_queue *q) | |
1148 | { | |
1149 | unsigned long flags; | |
1150 | ||
1151 | spin_lock_irqsave(q->queue_lock, flags); | |
1152 | __stop_queue(q); | |
1153 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1154 | } | |
1155 | ||
1156 | static void __start_queue(struct request_queue *q) | |
1157 | { | |
1158 | if (blk_queue_stopped(q)) | |
1159 | blk_start_queue(q); | |
1160 | } | |
1161 | ||
1162 | static void start_queue(struct request_queue *q) | |
1163 | { | |
1164 | unsigned long flags; | |
1165 | ||
1166 | spin_lock_irqsave(q->queue_lock, flags); | |
1167 | __start_queue(q); | |
1168 | spin_unlock_irqrestore(q->queue_lock, flags); | |
1169 | } | |
1170 | ||
11a68244 | 1171 | static void dm_done(struct request *clone, int error, bool mapped) |
cec47e3d | 1172 | { |
11a68244 | 1173 | int r = error; |
cec47e3d | 1174 | struct dm_rq_target_io *tio = clone->end_io_data; |
ba1cbad9 | 1175 | dm_request_endio_fn rq_end_io = NULL; |
cec47e3d | 1176 | |
ba1cbad9 MS |
1177 | if (tio->ti) { |
1178 | rq_end_io = tio->ti->type->rq_end_io; | |
1179 | ||
1180 | if (mapped && rq_end_io) | |
1181 | r = rq_end_io(tio->ti, clone, error, &tio->info); | |
1182 | } | |
cec47e3d | 1183 | |
7eee4ae2 MS |
1184 | if (unlikely(r == -EREMOTEIO && (clone->cmd_flags & REQ_WRITE_SAME) && |
1185 | !clone->q->limits.max_write_same_sectors)) | |
1186 | disable_write_same(tio->md); | |
1187 | ||
11a68244 | 1188 | if (r <= 0) |
cec47e3d | 1189 | /* The target wants to complete the I/O */ |
11a68244 KU |
1190 | dm_end_request(clone, r); |
1191 | else if (r == DM_ENDIO_INCOMPLETE) | |
cec47e3d KU |
1192 | /* The target will handle the I/O */ |
1193 | return; | |
11a68244 | 1194 | else if (r == DM_ENDIO_REQUEUE) |
cec47e3d KU |
1195 | /* The target wants to requeue the I/O */ |
1196 | dm_requeue_unmapped_request(clone); | |
1197 | else { | |
11a68244 | 1198 | DMWARN("unimplemented target endio return value: %d", r); |
cec47e3d KU |
1199 | BUG(); |
1200 | } | |
1201 | } | |
1202 | ||
11a68244 KU |
1203 | /* |
1204 | * Request completion handler for request-based dm | |
1205 | */ | |
1206 | static void dm_softirq_done(struct request *rq) | |
1207 | { | |
1208 | bool mapped = true; | |
466d89a6 KB |
1209 | struct dm_rq_target_io *tio = rq->special; |
1210 | struct request *clone = tio->clone; | |
11a68244 | 1211 | |
e5863d9a MS |
1212 | if (!clone) { |
1213 | blk_end_request_all(rq, tio->error); | |
1214 | rq_completed(tio->md, rq_data_dir(rq), false); | |
1215 | free_rq_tio(tio); | |
1216 | return; | |
1217 | } | |
11a68244 KU |
1218 | |
1219 | if (rq->cmd_flags & REQ_FAILED) | |
1220 | mapped = false; | |
1221 | ||
1222 | dm_done(clone, tio->error, mapped); | |
1223 | } | |
1224 | ||
cec47e3d KU |
1225 | /* |
1226 | * Complete the clone and the original request with the error status | |
1227 | * through softirq context. | |
1228 | */ | |
466d89a6 | 1229 | static void dm_complete_request(struct request *rq, int error) |
cec47e3d | 1230 | { |
466d89a6 | 1231 | struct dm_rq_target_io *tio = rq->special; |
cec47e3d KU |
1232 | |
1233 | tio->error = error; | |
cec47e3d KU |
1234 | blk_complete_request(rq); |
1235 | } | |
1236 | ||
1237 | /* | |
1238 | * Complete the not-mapped clone and the original request with the error status | |
1239 | * through softirq context. | |
1240 | * Target's rq_end_io() function isn't called. | |
e5863d9a | 1241 | * This may be used when the target's map_rq() or clone_and_map_rq() functions fail. |
cec47e3d | 1242 | */ |
466d89a6 | 1243 | static void dm_kill_unmapped_request(struct request *rq, int error) |
cec47e3d | 1244 | { |
cec47e3d | 1245 | rq->cmd_flags |= REQ_FAILED; |
466d89a6 | 1246 | dm_complete_request(rq, error); |
cec47e3d | 1247 | } |
cec47e3d KU |
1248 | |
1249 | /* | |
466d89a6 | 1250 | * Called with the clone's queue lock held |
cec47e3d KU |
1251 | */ |
1252 | static void end_clone_request(struct request *clone, int error) | |
1253 | { | |
466d89a6 KB |
1254 | struct dm_rq_target_io *tio = clone->end_io_data; |
1255 | ||
e5863d9a MS |
1256 | if (!clone->q->mq_ops) { |
1257 | /* | |
1258 | * For just cleaning up the information of the queue in which | |
1259 | * the clone was dispatched. | |
1260 | * The clone is *NOT* freed actually here because it is alloced | |
1261 | * from dm own mempool (REQ_ALLOCED isn't set). | |
1262 | */ | |
1263 | __blk_put_request(clone->q, clone); | |
1264 | } | |
cec47e3d KU |
1265 | |
1266 | /* | |
1267 | * Actual request completion is done in a softirq context which doesn't | |
466d89a6 | 1268 | * hold the clone's queue lock. Otherwise, deadlock could occur because: |
cec47e3d KU |
1269 | * - another request may be submitted by the upper level driver |
1270 | * of the stacking during the completion | |
1271 | * - the submission which requires queue lock may be done | |
466d89a6 | 1272 | * against this clone's queue |
cec47e3d | 1273 | */ |
466d89a6 | 1274 | dm_complete_request(tio->orig, error); |
cec47e3d KU |
1275 | } |
1276 | ||
56a67df7 MS |
1277 | /* |
1278 | * Return maximum size of I/O possible at the supplied sector up to the current | |
1279 | * target boundary. | |
1280 | */ | |
1281 | static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti) | |
1282 | { | |
1283 | sector_t target_offset = dm_target_offset(ti, sector); | |
1284 | ||
1285 | return ti->len - target_offset; | |
1286 | } | |
1287 | ||
1288 | static sector_t max_io_len(sector_t sector, struct dm_target *ti) | |
1da177e4 | 1289 | { |
56a67df7 | 1290 | sector_t len = max_io_len_target_boundary(sector, ti); |
542f9038 | 1291 | sector_t offset, max_len; |
1da177e4 LT |
1292 | |
1293 | /* | |
542f9038 | 1294 | * Does the target need to split even further? |
1da177e4 | 1295 | */ |
542f9038 MS |
1296 | if (ti->max_io_len) { |
1297 | offset = dm_target_offset(ti, sector); | |
1298 | if (unlikely(ti->max_io_len & (ti->max_io_len - 1))) | |
1299 | max_len = sector_div(offset, ti->max_io_len); | |
1300 | else | |
1301 | max_len = offset & (ti->max_io_len - 1); | |
1302 | max_len = ti->max_io_len - max_len; | |
1303 | ||
1304 | if (len > max_len) | |
1305 | len = max_len; | |
1da177e4 LT |
1306 | } |
1307 | ||
1308 | return len; | |
1309 | } | |
1310 | ||
542f9038 MS |
1311 | int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) |
1312 | { | |
1313 | if (len > UINT_MAX) { | |
1314 | DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)", | |
1315 | (unsigned long long)len, UINT_MAX); | |
1316 | ti->error = "Maximum size of target IO is too large"; | |
1317 | return -EINVAL; | |
1318 | } | |
1319 | ||
1320 | ti->max_io_len = (uint32_t) len; | |
1321 | ||
1322 | return 0; | |
1323 | } | |
1324 | EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); | |
1325 | ||
1dd40c3e MP |
1326 | /* |
1327 | * A target may call dm_accept_partial_bio only from the map routine. It is | |
1328 | * allowed for all bio types except REQ_FLUSH. | |
1329 | * | |
1330 | * dm_accept_partial_bio informs the dm that the target only wants to process | |
1331 | * additional n_sectors sectors of the bio and the rest of the data should be | |
1332 | * sent in a next bio. | |
1333 | * | |
1334 | * A diagram that explains the arithmetics: | |
1335 | * +--------------------+---------------+-------+ | |
1336 | * | 1 | 2 | 3 | | |
1337 | * +--------------------+---------------+-------+ | |
1338 | * | |
1339 | * <-------------- *tio->len_ptr ---------------> | |
1340 | * <------- bi_size -------> | |
1341 | * <-- n_sectors --> | |
1342 | * | |
1343 | * Region 1 was already iterated over with bio_advance or similar function. | |
1344 | * (it may be empty if the target doesn't use bio_advance) | |
1345 | * Region 2 is the remaining bio size that the target wants to process. | |
1346 | * (it may be empty if region 1 is non-empty, although there is no reason | |
1347 | * to make it empty) | |
1348 | * The target requires that region 3 is to be sent in the next bio. | |
1349 | * | |
1350 | * If the target wants to receive multiple copies of the bio (via num_*bios, etc), | |
1351 | * the partially processed part (the sum of regions 1+2) must be the same for all | |
1352 | * copies of the bio. | |
1353 | */ | |
1354 | void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) | |
1355 | { | |
1356 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); | |
1357 | unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; | |
1358 | BUG_ON(bio->bi_rw & REQ_FLUSH); | |
1359 | BUG_ON(bi_size > *tio->len_ptr); | |
1360 | BUG_ON(n_sectors > bi_size); | |
1361 | *tio->len_ptr -= bi_size - n_sectors; | |
1362 | bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT; | |
1363 | } | |
1364 | EXPORT_SYMBOL_GPL(dm_accept_partial_bio); | |
1365 | ||
bd2a49b8 | 1366 | static void __map_bio(struct dm_target_io *tio) |
1da177e4 LT |
1367 | { |
1368 | int r; | |
2056a782 | 1369 | sector_t sector; |
9faf400f | 1370 | struct mapped_device *md; |
dba14160 | 1371 | struct bio *clone = &tio->clone; |
bd2a49b8 | 1372 | struct dm_target *ti = tio->ti; |
1da177e4 | 1373 | |
1da177e4 | 1374 | clone->bi_end_io = clone_endio; |
1da177e4 LT |
1375 | |
1376 | /* | |
1377 | * Map the clone. If r == 0 we don't need to do | |
1378 | * anything, the target has assumed ownership of | |
1379 | * this io. | |
1380 | */ | |
1381 | atomic_inc(&tio->io->io_count); | |
4f024f37 | 1382 | sector = clone->bi_iter.bi_sector; |
7de3ee57 | 1383 | r = ti->type->map(ti, clone); |
45cbcd79 | 1384 | if (r == DM_MAPIO_REMAPPED) { |
1da177e4 | 1385 | /* the bio has been remapped so dispatch it */ |
2056a782 | 1386 | |
d07335e5 MS |
1387 | trace_block_bio_remap(bdev_get_queue(clone->bi_bdev), clone, |
1388 | tio->io->bio->bi_bdev->bd_dev, sector); | |
2056a782 | 1389 | |
1da177e4 | 1390 | generic_make_request(clone); |
2e93ccc1 KU |
1391 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
1392 | /* error the io and bail out, or requeue it if needed */ | |
9faf400f SB |
1393 | md = tio->io->md; |
1394 | dec_pending(tio->io, r); | |
9faf400f | 1395 | free_tio(md, tio); |
45cbcd79 KU |
1396 | } else if (r) { |
1397 | DMWARN("unimplemented target map return value: %d", r); | |
1398 | BUG(); | |
1da177e4 LT |
1399 | } |
1400 | } | |
1401 | ||
1402 | struct clone_info { | |
1403 | struct mapped_device *md; | |
1404 | struct dm_table *map; | |
1405 | struct bio *bio; | |
1406 | struct dm_io *io; | |
1407 | sector_t sector; | |
e0d6609a | 1408 | unsigned sector_count; |
1da177e4 LT |
1409 | }; |
1410 | ||
e0d6609a | 1411 | static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) |
bd2a49b8 | 1412 | { |
4f024f37 KO |
1413 | bio->bi_iter.bi_sector = sector; |
1414 | bio->bi_iter.bi_size = to_bytes(len); | |
1da177e4 LT |
1415 | } |
1416 | ||
1417 | /* | |
1418 | * Creates a bio that consists of range of complete bvecs. | |
1419 | */ | |
dba14160 | 1420 | static void clone_bio(struct dm_target_io *tio, struct bio *bio, |
1c3b13e6 | 1421 | sector_t sector, unsigned len) |
1da177e4 | 1422 | { |
dba14160 | 1423 | struct bio *clone = &tio->clone; |
1da177e4 | 1424 | |
1c3b13e6 KO |
1425 | __bio_clone_fast(clone, bio); |
1426 | ||
1427 | if (bio_integrity(bio)) | |
1428 | bio_integrity_clone(clone, bio, GFP_NOIO); | |
bd2a49b8 | 1429 | |
1c3b13e6 KO |
1430 | bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); |
1431 | clone->bi_iter.bi_size = to_bytes(len); | |
1432 | ||
1433 | if (bio_integrity(bio)) | |
1434 | bio_integrity_trim(clone, 0, len); | |
1da177e4 LT |
1435 | } |
1436 | ||
9015df24 | 1437 | static struct dm_target_io *alloc_tio(struct clone_info *ci, |
99778273 | 1438 | struct dm_target *ti, |
55a62eef | 1439 | unsigned target_bio_nr) |
f9ab94ce | 1440 | { |
dba14160 MP |
1441 | struct dm_target_io *tio; |
1442 | struct bio *clone; | |
1443 | ||
99778273 | 1444 | clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs); |
dba14160 | 1445 | tio = container_of(clone, struct dm_target_io, clone); |
f9ab94ce MP |
1446 | |
1447 | tio->io = ci->io; | |
1448 | tio->ti = ti; | |
55a62eef | 1449 | tio->target_bio_nr = target_bio_nr; |
9015df24 AK |
1450 | |
1451 | return tio; | |
1452 | } | |
1453 | ||
14fe594d AK |
1454 | static void __clone_and_map_simple_bio(struct clone_info *ci, |
1455 | struct dm_target *ti, | |
1dd40c3e | 1456 | unsigned target_bio_nr, unsigned *len) |
9015df24 | 1457 | { |
99778273 | 1458 | struct dm_target_io *tio = alloc_tio(ci, ti, target_bio_nr); |
dba14160 | 1459 | struct bio *clone = &tio->clone; |
9015df24 | 1460 | |
1dd40c3e MP |
1461 | tio->len_ptr = len; |
1462 | ||
99778273 | 1463 | __bio_clone_fast(clone, ci->bio); |
bd2a49b8 | 1464 | if (len) |
1dd40c3e | 1465 | bio_setup_sector(clone, ci->sector, *len); |
f9ab94ce | 1466 | |
bd2a49b8 | 1467 | __map_bio(tio); |
f9ab94ce MP |
1468 | } |
1469 | ||
14fe594d | 1470 | static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, |
1dd40c3e | 1471 | unsigned num_bios, unsigned *len) |
06a426ce | 1472 | { |
55a62eef | 1473 | unsigned target_bio_nr; |
06a426ce | 1474 | |
55a62eef | 1475 | for (target_bio_nr = 0; target_bio_nr < num_bios; target_bio_nr++) |
14fe594d | 1476 | __clone_and_map_simple_bio(ci, ti, target_bio_nr, len); |
06a426ce MS |
1477 | } |
1478 | ||
14fe594d | 1479 | static int __send_empty_flush(struct clone_info *ci) |
f9ab94ce | 1480 | { |
06a426ce | 1481 | unsigned target_nr = 0; |
f9ab94ce MP |
1482 | struct dm_target *ti; |
1483 | ||
b372d360 | 1484 | BUG_ON(bio_has_data(ci->bio)); |
f9ab94ce | 1485 | while ((ti = dm_table_get_target(ci->map, target_nr++))) |
1dd40c3e | 1486 | __send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL); |
f9ab94ce | 1487 | |
f9ab94ce MP |
1488 | return 0; |
1489 | } | |
1490 | ||
e4c93811 | 1491 | static void __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, |
1dd40c3e | 1492 | sector_t sector, unsigned *len) |
5ae89a87 | 1493 | { |
dba14160 | 1494 | struct bio *bio = ci->bio; |
5ae89a87 | 1495 | struct dm_target_io *tio; |
b0d8ed4d AK |
1496 | unsigned target_bio_nr; |
1497 | unsigned num_target_bios = 1; | |
5ae89a87 | 1498 | |
b0d8ed4d AK |
1499 | /* |
1500 | * Does the target want to receive duplicate copies of the bio? | |
1501 | */ | |
1502 | if (bio_data_dir(bio) == WRITE && ti->num_write_bios) | |
1503 | num_target_bios = ti->num_write_bios(ti, bio); | |
e4c93811 | 1504 | |
b0d8ed4d | 1505 | for (target_bio_nr = 0; target_bio_nr < num_target_bios; target_bio_nr++) { |
99778273 | 1506 | tio = alloc_tio(ci, ti, target_bio_nr); |
1dd40c3e MP |
1507 | tio->len_ptr = len; |
1508 | clone_bio(tio, bio, sector, *len); | |
b0d8ed4d AK |
1509 | __map_bio(tio); |
1510 | } | |
5ae89a87 MS |
1511 | } |
1512 | ||
55a62eef | 1513 | typedef unsigned (*get_num_bios_fn)(struct dm_target *ti); |
23508a96 | 1514 | |
55a62eef | 1515 | static unsigned get_num_discard_bios(struct dm_target *ti) |
23508a96 | 1516 | { |
55a62eef | 1517 | return ti->num_discard_bios; |
23508a96 MS |
1518 | } |
1519 | ||
55a62eef | 1520 | static unsigned get_num_write_same_bios(struct dm_target *ti) |
23508a96 | 1521 | { |
55a62eef | 1522 | return ti->num_write_same_bios; |
23508a96 MS |
1523 | } |
1524 | ||
1525 | typedef bool (*is_split_required_fn)(struct dm_target *ti); | |
1526 | ||
1527 | static bool is_split_required_for_discard(struct dm_target *ti) | |
1528 | { | |
55a62eef | 1529 | return ti->split_discard_bios; |
23508a96 MS |
1530 | } |
1531 | ||
14fe594d AK |
1532 | static int __send_changing_extent_only(struct clone_info *ci, |
1533 | get_num_bios_fn get_num_bios, | |
1534 | is_split_required_fn is_split_required) | |
5ae89a87 MS |
1535 | { |
1536 | struct dm_target *ti; | |
e0d6609a | 1537 | unsigned len; |
55a62eef | 1538 | unsigned num_bios; |
5ae89a87 | 1539 | |
a79245b3 MS |
1540 | do { |
1541 | ti = dm_table_find_target(ci->map, ci->sector); | |
1542 | if (!dm_target_is_valid(ti)) | |
1543 | return -EIO; | |
5ae89a87 | 1544 | |
5ae89a87 | 1545 | /* |
23508a96 MS |
1546 | * Even though the device advertised support for this type of |
1547 | * request, that does not mean every target supports it, and | |
936688d7 | 1548 | * reconfiguration might also have changed that since the |
a79245b3 | 1549 | * check was performed. |
5ae89a87 | 1550 | */ |
55a62eef AK |
1551 | num_bios = get_num_bios ? get_num_bios(ti) : 0; |
1552 | if (!num_bios) | |
a79245b3 | 1553 | return -EOPNOTSUPP; |
5ae89a87 | 1554 | |
23508a96 | 1555 | if (is_split_required && !is_split_required(ti)) |
e0d6609a | 1556 | len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); |
7acf0277 | 1557 | else |
e0d6609a | 1558 | len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti)); |
06a426ce | 1559 | |
1dd40c3e | 1560 | __send_duplicate_bios(ci, ti, num_bios, &len); |
a79245b3 MS |
1561 | |
1562 | ci->sector += len; | |
1563 | } while (ci->sector_count -= len); | |
5ae89a87 MS |
1564 | |
1565 | return 0; | |
1566 | } | |
1567 | ||
14fe594d | 1568 | static int __send_discard(struct clone_info *ci) |
23508a96 | 1569 | { |
14fe594d AK |
1570 | return __send_changing_extent_only(ci, get_num_discard_bios, |
1571 | is_split_required_for_discard); | |
23508a96 MS |
1572 | } |
1573 | ||
14fe594d | 1574 | static int __send_write_same(struct clone_info *ci) |
23508a96 | 1575 | { |
14fe594d | 1576 | return __send_changing_extent_only(ci, get_num_write_same_bios, NULL); |
23508a96 MS |
1577 | } |
1578 | ||
e4c93811 AK |
1579 | /* |
1580 | * Select the correct strategy for processing a non-flush bio. | |
1581 | */ | |
14fe594d | 1582 | static int __split_and_process_non_flush(struct clone_info *ci) |
1da177e4 | 1583 | { |
dba14160 | 1584 | struct bio *bio = ci->bio; |
512875bd | 1585 | struct dm_target *ti; |
1c3b13e6 | 1586 | unsigned len; |
1da177e4 | 1587 | |
5ae89a87 | 1588 | if (unlikely(bio->bi_rw & REQ_DISCARD)) |
14fe594d | 1589 | return __send_discard(ci); |
23508a96 | 1590 | else if (unlikely(bio->bi_rw & REQ_WRITE_SAME)) |
14fe594d | 1591 | return __send_write_same(ci); |
5ae89a87 | 1592 | |
512875bd JN |
1593 | ti = dm_table_find_target(ci->map, ci->sector); |
1594 | if (!dm_target_is_valid(ti)) | |
1595 | return -EIO; | |
1596 | ||
1c3b13e6 | 1597 | len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count); |
1da177e4 | 1598 | |
1dd40c3e | 1599 | __clone_and_map_data_bio(ci, ti, ci->sector, &len); |
1da177e4 | 1600 | |
1c3b13e6 KO |
1601 | ci->sector += len; |
1602 | ci->sector_count -= len; | |
1da177e4 | 1603 | |
1c3b13e6 | 1604 | return 0; |
1da177e4 LT |
1605 | } |
1606 | ||
1607 | /* | |
14fe594d | 1608 | * Entry point to split a bio into clones and submit them to the targets. |
1da177e4 | 1609 | */ |
83d5e5b0 MP |
1610 | static void __split_and_process_bio(struct mapped_device *md, |
1611 | struct dm_table *map, struct bio *bio) | |
1da177e4 LT |
1612 | { |
1613 | struct clone_info ci; | |
512875bd | 1614 | int error = 0; |
1da177e4 | 1615 | |
83d5e5b0 | 1616 | if (unlikely(!map)) { |
6a8736d1 | 1617 | bio_io_error(bio); |
f0b9a450 MP |
1618 | return; |
1619 | } | |
692d0eb9 | 1620 | |
83d5e5b0 | 1621 | ci.map = map; |
1da177e4 | 1622 | ci.md = md; |
1da177e4 LT |
1623 | ci.io = alloc_io(md); |
1624 | ci.io->error = 0; | |
1625 | atomic_set(&ci.io->io_count, 1); | |
1626 | ci.io->bio = bio; | |
1627 | ci.io->md = md; | |
f88fb981 | 1628 | spin_lock_init(&ci.io->endio_lock); |
4f024f37 | 1629 | ci.sector = bio->bi_iter.bi_sector; |
1da177e4 | 1630 | |
3eaf840e | 1631 | start_io_acct(ci.io); |
bd2a49b8 | 1632 | |
b372d360 MS |
1633 | if (bio->bi_rw & REQ_FLUSH) { |
1634 | ci.bio = &ci.md->flush_bio; | |
1635 | ci.sector_count = 0; | |
14fe594d | 1636 | error = __send_empty_flush(&ci); |
b372d360 MS |
1637 | /* dec_pending submits any data associated with flush */ |
1638 | } else { | |
6a8736d1 | 1639 | ci.bio = bio; |
d87f4c14 | 1640 | ci.sector_count = bio_sectors(bio); |
b372d360 | 1641 | while (ci.sector_count && !error) |
14fe594d | 1642 | error = __split_and_process_non_flush(&ci); |
d87f4c14 | 1643 | } |
1da177e4 LT |
1644 | |
1645 | /* drop the extra reference count */ | |
512875bd | 1646 | dec_pending(ci.io, error); |
1da177e4 LT |
1647 | } |
1648 | /*----------------------------------------------------------------- | |
1649 | * CRUD END | |
1650 | *---------------------------------------------------------------*/ | |
1651 | ||
f6fccb12 MB |
1652 | static int dm_merge_bvec(struct request_queue *q, |
1653 | struct bvec_merge_data *bvm, | |
1654 | struct bio_vec *biovec) | |
1655 | { | |
1656 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 | 1657 | struct dm_table *map = dm_get_live_table_fast(md); |
f6fccb12 MB |
1658 | struct dm_target *ti; |
1659 | sector_t max_sectors; | |
5037108a | 1660 | int max_size = 0; |
f6fccb12 MB |
1661 | |
1662 | if (unlikely(!map)) | |
5037108a | 1663 | goto out; |
f6fccb12 MB |
1664 | |
1665 | ti = dm_table_find_target(map, bvm->bi_sector); | |
b01cd5ac | 1666 | if (!dm_target_is_valid(ti)) |
83d5e5b0 | 1667 | goto out; |
f6fccb12 MB |
1668 | |
1669 | /* | |
1670 | * Find maximum amount of I/O that won't need splitting | |
1671 | */ | |
56a67df7 | 1672 | max_sectors = min(max_io_len(bvm->bi_sector, ti), |
148e51ba | 1673 | (sector_t) queue_max_sectors(q)); |
f6fccb12 | 1674 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; |
148e51ba | 1675 | if (unlikely(max_size < 0)) /* this shouldn't _ever_ happen */ |
f6fccb12 MB |
1676 | max_size = 0; |
1677 | ||
1678 | /* | |
1679 | * merge_bvec_fn() returns number of bytes | |
1680 | * it can accept at this offset | |
1681 | * max is precomputed maximal io size | |
1682 | */ | |
1683 | if (max_size && ti->type->merge) | |
1684 | max_size = ti->type->merge(ti, bvm, biovec, max_size); | |
8cbeb67a MP |
1685 | /* |
1686 | * If the target doesn't support merge method and some of the devices | |
148e51ba MS |
1687 | * provided their merge_bvec method (we know this by looking for the |
1688 | * max_hw_sectors that dm_set_device_limits may set), then we can't | |
1689 | * allow bios with multiple vector entries. So always set max_size | |
1690 | * to 0, and the code below allows just one page. | |
8cbeb67a MP |
1691 | */ |
1692 | else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9) | |
8cbeb67a | 1693 | max_size = 0; |
f6fccb12 | 1694 | |
5037108a | 1695 | out: |
83d5e5b0 | 1696 | dm_put_live_table_fast(md); |
f6fccb12 MB |
1697 | /* |
1698 | * Always allow an entire first page | |
1699 | */ | |
1700 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) | |
1701 | max_size = biovec->bv_len; | |
1702 | ||
f6fccb12 MB |
1703 | return max_size; |
1704 | } | |
1705 | ||
1da177e4 LT |
1706 | /* |
1707 | * The request function that just remaps the bio built up by | |
1708 | * dm_merge_bvec. | |
1709 | */ | |
ff36ab34 | 1710 | static void dm_make_request(struct request_queue *q, struct bio *bio) |
1da177e4 | 1711 | { |
12f03a49 | 1712 | int rw = bio_data_dir(bio); |
1da177e4 | 1713 | struct mapped_device *md = q->queuedata; |
83d5e5b0 MP |
1714 | int srcu_idx; |
1715 | struct dm_table *map; | |
1da177e4 | 1716 | |
83d5e5b0 | 1717 | map = dm_get_live_table(md, &srcu_idx); |
1da177e4 | 1718 | |
18c0b223 | 1719 | generic_start_io_acct(rw, bio_sectors(bio), &dm_disk(md)->part0); |
12f03a49 | 1720 | |
6a8736d1 TH |
1721 | /* if we're suspended, we have to queue this io for later */ |
1722 | if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { | |
83d5e5b0 | 1723 | dm_put_live_table(md, srcu_idx); |
1da177e4 | 1724 | |
6a8736d1 TH |
1725 | if (bio_rw(bio) != READA) |
1726 | queue_io(md, bio); | |
1727 | else | |
54d9a1b4 | 1728 | bio_io_error(bio); |
5a7bbad2 | 1729 | return; |
1da177e4 LT |
1730 | } |
1731 | ||
83d5e5b0 MP |
1732 | __split_and_process_bio(md, map, bio); |
1733 | dm_put_live_table(md, srcu_idx); | |
5a7bbad2 | 1734 | return; |
cec47e3d KU |
1735 | } |
1736 | ||
fd2ed4d2 | 1737 | int dm_request_based(struct mapped_device *md) |
cec47e3d KU |
1738 | { |
1739 | return blk_queue_stackable(md->queue); | |
1740 | } | |
1741 | ||
466d89a6 | 1742 | static void dm_dispatch_clone_request(struct request *clone, struct request *rq) |
cec47e3d KU |
1743 | { |
1744 | int r; | |
1745 | ||
466d89a6 KB |
1746 | if (blk_queue_io_stat(clone->q)) |
1747 | clone->cmd_flags |= REQ_IO_STAT; | |
cec47e3d | 1748 | |
466d89a6 KB |
1749 | clone->start_time = jiffies; |
1750 | r = blk_insert_cloned_request(clone->q, clone); | |
cec47e3d | 1751 | if (r) |
466d89a6 | 1752 | /* must complete clone in terms of original request */ |
cec47e3d KU |
1753 | dm_complete_request(rq, r); |
1754 | } | |
cec47e3d | 1755 | |
cec47e3d KU |
1756 | static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig, |
1757 | void *data) | |
1758 | { | |
1759 | struct dm_rq_target_io *tio = data; | |
94818742 KO |
1760 | struct dm_rq_clone_bio_info *info = |
1761 | container_of(bio, struct dm_rq_clone_bio_info, clone); | |
cec47e3d KU |
1762 | |
1763 | info->orig = bio_orig; | |
1764 | info->tio = tio; | |
1765 | bio->bi_end_io = end_clone_bio; | |
cec47e3d KU |
1766 | |
1767 | return 0; | |
1768 | } | |
1769 | ||
1770 | static int setup_clone(struct request *clone, struct request *rq, | |
1ae49ea2 | 1771 | struct dm_rq_target_io *tio, gfp_t gfp_mask) |
cec47e3d | 1772 | { |
d0bcb878 | 1773 | int r; |
cec47e3d | 1774 | |
1ae49ea2 | 1775 | r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask, |
29e4013d TH |
1776 | dm_rq_bio_constructor, tio); |
1777 | if (r) | |
1778 | return r; | |
cec47e3d | 1779 | |
29e4013d TH |
1780 | clone->cmd = rq->cmd; |
1781 | clone->cmd_len = rq->cmd_len; | |
1782 | clone->sense = rq->sense; | |
cec47e3d KU |
1783 | clone->end_io = end_clone_request; |
1784 | clone->end_io_data = tio; | |
1785 | ||
1ae49ea2 MS |
1786 | tio->clone = clone; |
1787 | ||
cec47e3d KU |
1788 | return 0; |
1789 | } | |
1790 | ||
6facdaff | 1791 | static struct request *clone_rq(struct request *rq, struct mapped_device *md, |
466d89a6 | 1792 | struct dm_rq_target_io *tio, gfp_t gfp_mask) |
1ae49ea2 MS |
1793 | { |
1794 | struct request *clone = alloc_clone_request(md, gfp_mask); | |
1795 | ||
1796 | if (!clone) | |
1797 | return NULL; | |
1798 | ||
1799 | blk_rq_init(NULL, clone); | |
1800 | if (setup_clone(clone, rq, tio, gfp_mask)) { | |
1801 | /* -ENOMEM */ | |
1802 | free_clone_request(md, clone); | |
1803 | return NULL; | |
1804 | } | |
1805 | ||
1806 | return clone; | |
1807 | } | |
1808 | ||
2eb6e1e3 KB |
1809 | static void map_tio_request(struct kthread_work *work); |
1810 | ||
466d89a6 KB |
1811 | static struct dm_rq_target_io *prep_tio(struct request *rq, |
1812 | struct mapped_device *md, gfp_t gfp_mask) | |
6facdaff | 1813 | { |
6facdaff | 1814 | struct dm_rq_target_io *tio; |
e5863d9a MS |
1815 | int srcu_idx; |
1816 | struct dm_table *table; | |
6facdaff KU |
1817 | |
1818 | tio = alloc_rq_tio(md, gfp_mask); | |
1819 | if (!tio) | |
1820 | return NULL; | |
1821 | ||
1822 | tio->md = md; | |
1823 | tio->ti = NULL; | |
1ae49ea2 | 1824 | tio->clone = NULL; |
6facdaff KU |
1825 | tio->orig = rq; |
1826 | tio->error = 0; | |
1827 | memset(&tio->info, 0, sizeof(tio->info)); | |
2eb6e1e3 | 1828 | init_kthread_work(&tio->work, map_tio_request); |
6facdaff | 1829 | |
e5863d9a MS |
1830 | table = dm_get_live_table(md, &srcu_idx); |
1831 | if (!dm_table_mq_request_based(table)) { | |
1832 | if (!clone_rq(rq, md, tio, gfp_mask)) { | |
1833 | dm_put_live_table(md, srcu_idx); | |
1834 | free_rq_tio(tio); | |
1835 | return NULL; | |
1836 | } | |
6facdaff | 1837 | } |
e5863d9a | 1838 | dm_put_live_table(md, srcu_idx); |
6facdaff | 1839 | |
466d89a6 | 1840 | return tio; |
6facdaff KU |
1841 | } |
1842 | ||
cec47e3d KU |
1843 | /* |
1844 | * Called with the queue lock held. | |
1845 | */ | |
1846 | static int dm_prep_fn(struct request_queue *q, struct request *rq) | |
1847 | { | |
1848 | struct mapped_device *md = q->queuedata; | |
466d89a6 | 1849 | struct dm_rq_target_io *tio; |
cec47e3d | 1850 | |
cec47e3d KU |
1851 | if (unlikely(rq->special)) { |
1852 | DMWARN("Already has something in rq->special."); | |
1853 | return BLKPREP_KILL; | |
1854 | } | |
1855 | ||
466d89a6 KB |
1856 | tio = prep_tio(rq, md, GFP_ATOMIC); |
1857 | if (!tio) | |
cec47e3d | 1858 | return BLKPREP_DEFER; |
cec47e3d | 1859 | |
466d89a6 | 1860 | rq->special = tio; |
cec47e3d KU |
1861 | rq->cmd_flags |= REQ_DONTPREP; |
1862 | ||
1863 | return BLKPREP_OK; | |
1864 | } | |
1865 | ||
9eef87da KU |
1866 | /* |
1867 | * Returns: | |
e5863d9a MS |
1868 | * 0 : the request has been processed |
1869 | * DM_MAPIO_REQUEUE : the original request needs to be requeued | |
1870 | * < 0 : the request was completed due to failure | |
9eef87da | 1871 | */ |
466d89a6 | 1872 | static int map_request(struct dm_target *ti, struct request *rq, |
9eef87da | 1873 | struct mapped_device *md) |
cec47e3d | 1874 | { |
e5863d9a | 1875 | int r; |
466d89a6 | 1876 | struct dm_rq_target_io *tio = rq->special; |
e5863d9a MS |
1877 | struct request *clone = NULL; |
1878 | ||
1879 | if (tio->clone) { | |
1880 | clone = tio->clone; | |
1881 | r = ti->type->map_rq(ti, clone, &tio->info); | |
1882 | } else { | |
1883 | r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone); | |
1884 | if (r < 0) { | |
1885 | /* The target wants to complete the I/O */ | |
1886 | dm_kill_unmapped_request(rq, r); | |
1887 | return r; | |
1888 | } | |
1889 | if (IS_ERR(clone)) | |
1890 | return DM_MAPIO_REQUEUE; | |
1891 | if (setup_clone(clone, rq, tio, GFP_KERNEL)) { | |
1892 | /* -ENOMEM */ | |
1893 | ti->type->release_clone_rq(clone); | |
1894 | return DM_MAPIO_REQUEUE; | |
1895 | } | |
1896 | } | |
cec47e3d | 1897 | |
cec47e3d KU |
1898 | switch (r) { |
1899 | case DM_MAPIO_SUBMITTED: | |
1900 | /* The target has taken the I/O to submit by itself later */ | |
1901 | break; | |
1902 | case DM_MAPIO_REMAPPED: | |
1903 | /* The target has remapped the I/O so dispatch it */ | |
6db4ccd6 | 1904 | trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)), |
466d89a6 KB |
1905 | blk_rq_pos(rq)); |
1906 | dm_dispatch_clone_request(clone, rq); | |
cec47e3d KU |
1907 | break; |
1908 | case DM_MAPIO_REQUEUE: | |
1909 | /* The target wants to requeue the I/O */ | |
1910 | dm_requeue_unmapped_request(clone); | |
1911 | break; | |
1912 | default: | |
1913 | if (r > 0) { | |
1914 | DMWARN("unimplemented target map return value: %d", r); | |
1915 | BUG(); | |
1916 | } | |
1917 | ||
1918 | /* The target wants to complete the I/O */ | |
466d89a6 | 1919 | dm_kill_unmapped_request(rq, r); |
e5863d9a | 1920 | return r; |
cec47e3d | 1921 | } |
9eef87da | 1922 | |
e5863d9a | 1923 | return 0; |
cec47e3d KU |
1924 | } |
1925 | ||
2eb6e1e3 | 1926 | static void map_tio_request(struct kthread_work *work) |
ba1cbad9 | 1927 | { |
2eb6e1e3 | 1928 | struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work); |
e5863d9a MS |
1929 | struct request *rq = tio->orig; |
1930 | struct mapped_device *md = tio->md; | |
ba1cbad9 | 1931 | |
e5863d9a MS |
1932 | if (map_request(tio->ti, rq, md) == DM_MAPIO_REQUEUE) |
1933 | dm_requeue_unmapped_original_request(md, rq); | |
2eb6e1e3 KB |
1934 | } |
1935 | ||
466d89a6 | 1936 | static void dm_start_request(struct mapped_device *md, struct request *orig) |
ba1cbad9 | 1937 | { |
ba1cbad9 | 1938 | blk_start_request(orig); |
466d89a6 | 1939 | atomic_inc(&md->pending[rq_data_dir(orig)]); |
ba1cbad9 | 1940 | |
0ce65797 MS |
1941 | if (md->seq_rq_merge_deadline_usecs) { |
1942 | md->last_rq_pos = rq_end_sector(orig); | |
1943 | md->last_rq_rw = rq_data_dir(orig); | |
1944 | md->last_rq_start_time = ktime_get(); | |
1945 | } | |
de3ec86d | 1946 | |
ba1cbad9 MS |
1947 | /* |
1948 | * Hold the md reference here for the in-flight I/O. | |
1949 | * We can't rely on the reference count by device opener, | |
1950 | * because the device may be closed during the request completion | |
1951 | * when all bios are completed. | |
1952 | * See the comment in rq_completed() too. | |
1953 | */ | |
1954 | dm_get(md); | |
ba1cbad9 MS |
1955 | } |
1956 | ||
0ce65797 MS |
1957 | #define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000 |
1958 | ||
1959 | ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf) | |
1960 | { | |
1961 | return sprintf(buf, "%u\n", md->seq_rq_merge_deadline_usecs); | |
1962 | } | |
1963 | ||
1964 | ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md, | |
1965 | const char *buf, size_t count) | |
1966 | { | |
1967 | unsigned deadline; | |
1968 | ||
1969 | if (!dm_request_based(md)) | |
1970 | return count; | |
1971 | ||
1972 | if (kstrtouint(buf, 10, &deadline)) | |
1973 | return -EINVAL; | |
1974 | ||
1975 | if (deadline > MAX_SEQ_RQ_MERGE_DEADLINE_USECS) | |
1976 | deadline = MAX_SEQ_RQ_MERGE_DEADLINE_USECS; | |
1977 | ||
1978 | md->seq_rq_merge_deadline_usecs = deadline; | |
1979 | ||
1980 | return count; | |
1981 | } | |
1982 | ||
1983 | static bool dm_request_peeked_before_merge_deadline(struct mapped_device *md) | |
1984 | { | |
1985 | ktime_t kt_deadline; | |
1986 | ||
1987 | if (!md->seq_rq_merge_deadline_usecs) | |
1988 | return false; | |
1989 | ||
1990 | kt_deadline = ns_to_ktime((u64)md->seq_rq_merge_deadline_usecs * NSEC_PER_USEC); | |
1991 | kt_deadline = ktime_add_safe(md->last_rq_start_time, kt_deadline); | |
1992 | ||
1993 | return !ktime_after(ktime_get(), kt_deadline); | |
1994 | } | |
1995 | ||
cec47e3d KU |
1996 | /* |
1997 | * q->request_fn for request-based dm. | |
1998 | * Called with the queue lock held. | |
1999 | */ | |
2000 | static void dm_request_fn(struct request_queue *q) | |
2001 | { | |
2002 | struct mapped_device *md = q->queuedata; | |
83d5e5b0 MP |
2003 | int srcu_idx; |
2004 | struct dm_table *map = dm_get_live_table(md, &srcu_idx); | |
cec47e3d | 2005 | struct dm_target *ti; |
466d89a6 | 2006 | struct request *rq; |
2eb6e1e3 | 2007 | struct dm_rq_target_io *tio; |
29e4013d | 2008 | sector_t pos; |
cec47e3d KU |
2009 | |
2010 | /* | |
b4324fee KU |
2011 | * For suspend, check blk_queue_stopped() and increment |
2012 | * ->pending within a single queue_lock not to increment the | |
2013 | * number of in-flight I/Os after the queue is stopped in | |
2014 | * dm_suspend(). | |
cec47e3d | 2015 | */ |
7eaceacc | 2016 | while (!blk_queue_stopped(q)) { |
cec47e3d KU |
2017 | rq = blk_peek_request(q); |
2018 | if (!rq) | |
9d1deb83 | 2019 | goto out; |
cec47e3d | 2020 | |
29e4013d TH |
2021 | /* always use block 0 to find the target for flushes for now */ |
2022 | pos = 0; | |
2023 | if (!(rq->cmd_flags & REQ_FLUSH)) | |
2024 | pos = blk_rq_pos(rq); | |
2025 | ||
2026 | ti = dm_table_find_target(map, pos); | |
ba1cbad9 MS |
2027 | if (!dm_target_is_valid(ti)) { |
2028 | /* | |
466d89a6 | 2029 | * Must perform setup, that rq_completed() requires, |
ba1cbad9 MS |
2030 | * before calling dm_kill_unmapped_request |
2031 | */ | |
2032 | DMERR_LIMIT("request attempted access beyond the end of device"); | |
466d89a6 KB |
2033 | dm_start_request(md, rq); |
2034 | dm_kill_unmapped_request(rq, -EIO); | |
ba1cbad9 MS |
2035 | continue; |
2036 | } | |
d0bcb878 | 2037 | |
0ce65797 MS |
2038 | if (dm_request_peeked_before_merge_deadline(md) && |
2039 | md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 && | |
de3ec86d MS |
2040 | md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) |
2041 | goto delay_and_out; | |
2042 | ||
cec47e3d | 2043 | if (ti->type->busy && ti->type->busy(ti)) |
7eaceacc | 2044 | goto delay_and_out; |
cec47e3d | 2045 | |
466d89a6 | 2046 | dm_start_request(md, rq); |
9eef87da | 2047 | |
2eb6e1e3 KB |
2048 | tio = rq->special; |
2049 | /* Establish tio->ti before queuing work (map_tio_request) */ | |
2050 | tio->ti = ti; | |
2051 | queue_kthread_work(&md->kworker, &tio->work); | |
052189a2 | 2052 | BUG_ON(!irqs_disabled()); |
cec47e3d KU |
2053 | } |
2054 | ||
2055 | goto out; | |
2056 | ||
7eaceacc | 2057 | delay_and_out: |
d548b34b | 2058 | blk_delay_queue(q, HZ / 100); |
cec47e3d | 2059 | out: |
83d5e5b0 | 2060 | dm_put_live_table(md, srcu_idx); |
cec47e3d KU |
2061 | } |
2062 | ||
1da177e4 LT |
2063 | static int dm_any_congested(void *congested_data, int bdi_bits) |
2064 | { | |
8a57dfc6 CS |
2065 | int r = bdi_bits; |
2066 | struct mapped_device *md = congested_data; | |
2067 | struct dm_table *map; | |
1da177e4 | 2068 | |
1eb787ec | 2069 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
83d5e5b0 | 2070 | map = dm_get_live_table_fast(md); |
8a57dfc6 | 2071 | if (map) { |
cec47e3d KU |
2072 | /* |
2073 | * Request-based dm cares about only own queue for | |
2074 | * the query about congestion status of request_queue | |
2075 | */ | |
2076 | if (dm_request_based(md)) | |
2077 | r = md->queue->backing_dev_info.state & | |
2078 | bdi_bits; | |
2079 | else | |
2080 | r = dm_table_any_congested(map, bdi_bits); | |
8a57dfc6 | 2081 | } |
83d5e5b0 | 2082 | dm_put_live_table_fast(md); |
8a57dfc6 CS |
2083 | } |
2084 | ||
1da177e4 LT |
2085 | return r; |
2086 | } | |
2087 | ||
2088 | /*----------------------------------------------------------------- | |
2089 | * An IDR is used to keep track of allocated minor numbers. | |
2090 | *---------------------------------------------------------------*/ | |
2b06cfff | 2091 | static void free_minor(int minor) |
1da177e4 | 2092 | { |
f32c10b0 | 2093 | spin_lock(&_minor_lock); |
1da177e4 | 2094 | idr_remove(&_minor_idr, minor); |
f32c10b0 | 2095 | spin_unlock(&_minor_lock); |
1da177e4 LT |
2096 | } |
2097 | ||
2098 | /* | |
2099 | * See if the device with a specific minor # is free. | |
2100 | */ | |
cf13ab8e | 2101 | static int specific_minor(int minor) |
1da177e4 | 2102 | { |
c9d76be6 | 2103 | int r; |
1da177e4 LT |
2104 | |
2105 | if (minor >= (1 << MINORBITS)) | |
2106 | return -EINVAL; | |
2107 | ||
c9d76be6 | 2108 | idr_preload(GFP_KERNEL); |
f32c10b0 | 2109 | spin_lock(&_minor_lock); |
1da177e4 | 2110 | |
c9d76be6 | 2111 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT); |
1da177e4 | 2112 | |
f32c10b0 | 2113 | spin_unlock(&_minor_lock); |
c9d76be6 TH |
2114 | idr_preload_end(); |
2115 | if (r < 0) | |
2116 | return r == -ENOSPC ? -EBUSY : r; | |
2117 | return 0; | |
1da177e4 LT |
2118 | } |
2119 | ||
cf13ab8e | 2120 | static int next_free_minor(int *minor) |
1da177e4 | 2121 | { |
c9d76be6 | 2122 | int r; |
62f75c2f | 2123 | |
c9d76be6 | 2124 | idr_preload(GFP_KERNEL); |
f32c10b0 | 2125 | spin_lock(&_minor_lock); |
1da177e4 | 2126 | |
c9d76be6 | 2127 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT); |
1da177e4 | 2128 | |
f32c10b0 | 2129 | spin_unlock(&_minor_lock); |
c9d76be6 TH |
2130 | idr_preload_end(); |
2131 | if (r < 0) | |
2132 | return r; | |
2133 | *minor = r; | |
2134 | return 0; | |
1da177e4 LT |
2135 | } |
2136 | ||
83d5cde4 | 2137 | static const struct block_device_operations dm_blk_dops; |
1da177e4 | 2138 | |
53d5914f MP |
2139 | static void dm_wq_work(struct work_struct *work); |
2140 | ||
4a0b4ddf MS |
2141 | static void dm_init_md_queue(struct mapped_device *md) |
2142 | { | |
2143 | /* | |
2144 | * Request-based dm devices cannot be stacked on top of bio-based dm | |
2145 | * devices. The type of this dm device has not been decided yet. | |
2146 | * The type is decided at the first table loading time. | |
2147 | * To prevent problematic device stacking, clear the queue flag | |
2148 | * for request stacking support until then. | |
2149 | * | |
2150 | * This queue is new, so no concurrency on the queue_flags. | |
2151 | */ | |
2152 | queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue); | |
2153 | ||
2154 | md->queue->queuedata = md; | |
2155 | md->queue->backing_dev_info.congested_fn = dm_any_congested; | |
2156 | md->queue->backing_dev_info.congested_data = md; | |
ff36ab34 | 2157 | |
4a0b4ddf | 2158 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); |
4a0b4ddf MS |
2159 | } |
2160 | ||
1da177e4 LT |
2161 | /* |
2162 | * Allocate and initialise a blank device with a given minor. | |
2163 | */ | |
2b06cfff | 2164 | static struct mapped_device *alloc_dev(int minor) |
1da177e4 LT |
2165 | { |
2166 | int r; | |
cf13ab8e | 2167 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
ba61fdd1 | 2168 | void *old_md; |
1da177e4 LT |
2169 | |
2170 | if (!md) { | |
2171 | DMWARN("unable to allocate device, out of memory."); | |
2172 | return NULL; | |
2173 | } | |
2174 | ||
10da4f79 | 2175 | if (!try_module_get(THIS_MODULE)) |
6ed7ade8 | 2176 | goto bad_module_get; |
10da4f79 | 2177 | |
1da177e4 | 2178 | /* get a minor number for the dev */ |
2b06cfff | 2179 | if (minor == DM_ANY_MINOR) |
cf13ab8e | 2180 | r = next_free_minor(&minor); |
2b06cfff | 2181 | else |
cf13ab8e | 2182 | r = specific_minor(minor); |
1da177e4 | 2183 | if (r < 0) |
6ed7ade8 | 2184 | goto bad_minor; |
1da177e4 | 2185 | |
83d5e5b0 MP |
2186 | r = init_srcu_struct(&md->io_barrier); |
2187 | if (r < 0) | |
2188 | goto bad_io_barrier; | |
2189 | ||
a5664dad | 2190 | md->type = DM_TYPE_NONE; |
e61290a4 | 2191 | mutex_init(&md->suspend_lock); |
a5664dad | 2192 | mutex_init(&md->type_lock); |
86f1152b | 2193 | mutex_init(&md->table_devices_lock); |
022c2611 | 2194 | spin_lock_init(&md->deferred_lock); |
1da177e4 | 2195 | atomic_set(&md->holders, 1); |
5c6bd75d | 2196 | atomic_set(&md->open_count, 0); |
1da177e4 | 2197 | atomic_set(&md->event_nr, 0); |
7a8c3d3b MA |
2198 | atomic_set(&md->uevent_seq, 0); |
2199 | INIT_LIST_HEAD(&md->uevent_list); | |
86f1152b | 2200 | INIT_LIST_HEAD(&md->table_devices); |
7a8c3d3b | 2201 | spin_lock_init(&md->uevent_lock); |
1da177e4 | 2202 | |
4a0b4ddf | 2203 | md->queue = blk_alloc_queue(GFP_KERNEL); |
1da177e4 | 2204 | if (!md->queue) |
6ed7ade8 | 2205 | goto bad_queue; |
1da177e4 | 2206 | |
4a0b4ddf | 2207 | dm_init_md_queue(md); |
9faf400f | 2208 | |
1da177e4 LT |
2209 | md->disk = alloc_disk(1); |
2210 | if (!md->disk) | |
6ed7ade8 | 2211 | goto bad_disk; |
1da177e4 | 2212 | |
316d315b NK |
2213 | atomic_set(&md->pending[0], 0); |
2214 | atomic_set(&md->pending[1], 0); | |
f0b04115 | 2215 | init_waitqueue_head(&md->wait); |
53d5914f | 2216 | INIT_WORK(&md->work, dm_wq_work); |
f0b04115 | 2217 | init_waitqueue_head(&md->eventq); |
2995fa78 | 2218 | init_completion(&md->kobj_holder.completion); |
2eb6e1e3 | 2219 | md->kworker_task = NULL; |
f0b04115 | 2220 | |
1da177e4 LT |
2221 | md->disk->major = _major; |
2222 | md->disk->first_minor = minor; | |
2223 | md->disk->fops = &dm_blk_dops; | |
2224 | md->disk->queue = md->queue; | |
2225 | md->disk->private_data = md; | |
2226 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
2227 | add_disk(md->disk); | |
7e51f257 | 2228 | format_dev_t(md->name, MKDEV(_major, minor)); |
1da177e4 | 2229 | |
670368a8 | 2230 | md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0); |
304f3f6a MB |
2231 | if (!md->wq) |
2232 | goto bad_thread; | |
2233 | ||
32a926da MP |
2234 | md->bdev = bdget_disk(md->disk, 0); |
2235 | if (!md->bdev) | |
2236 | goto bad_bdev; | |
2237 | ||
6a8736d1 TH |
2238 | bio_init(&md->flush_bio); |
2239 | md->flush_bio.bi_bdev = md->bdev; | |
2240 | md->flush_bio.bi_rw = WRITE_FLUSH; | |
2241 | ||
fd2ed4d2 MP |
2242 | dm_stats_init(&md->stats); |
2243 | ||
ba61fdd1 | 2244 | /* Populate the mapping, nobody knows we exist yet */ |
f32c10b0 | 2245 | spin_lock(&_minor_lock); |
ba61fdd1 | 2246 | old_md = idr_replace(&_minor_idr, md, minor); |
f32c10b0 | 2247 | spin_unlock(&_minor_lock); |
ba61fdd1 JM |
2248 | |
2249 | BUG_ON(old_md != MINOR_ALLOCED); | |
2250 | ||
1da177e4 LT |
2251 | return md; |
2252 | ||
32a926da MP |
2253 | bad_bdev: |
2254 | destroy_workqueue(md->wq); | |
304f3f6a | 2255 | bad_thread: |
03022c54 | 2256 | del_gendisk(md->disk); |
304f3f6a | 2257 | put_disk(md->disk); |
6ed7ade8 | 2258 | bad_disk: |
1312f40e | 2259 | blk_cleanup_queue(md->queue); |
6ed7ade8 | 2260 | bad_queue: |
83d5e5b0 MP |
2261 | cleanup_srcu_struct(&md->io_barrier); |
2262 | bad_io_barrier: | |
1da177e4 | 2263 | free_minor(minor); |
6ed7ade8 | 2264 | bad_minor: |
10da4f79 | 2265 | module_put(THIS_MODULE); |
6ed7ade8 | 2266 | bad_module_get: |
1da177e4 LT |
2267 | kfree(md); |
2268 | return NULL; | |
2269 | } | |
2270 | ||
ae9da83f JN |
2271 | static void unlock_fs(struct mapped_device *md); |
2272 | ||
1da177e4 LT |
2273 | static void free_dev(struct mapped_device *md) |
2274 | { | |
f331c029 | 2275 | int minor = MINOR(disk_devt(md->disk)); |
63d94e48 | 2276 | |
32a926da | 2277 | unlock_fs(md); |
304f3f6a | 2278 | destroy_workqueue(md->wq); |
2eb6e1e3 KB |
2279 | |
2280 | if (md->kworker_task) | |
2281 | kthread_stop(md->kworker_task); | |
e6ee8c0b KU |
2282 | if (md->io_pool) |
2283 | mempool_destroy(md->io_pool); | |
1ae49ea2 MS |
2284 | if (md->rq_pool) |
2285 | mempool_destroy(md->rq_pool); | |
e6ee8c0b KU |
2286 | if (md->bs) |
2287 | bioset_free(md->bs); | |
63a4f065 | 2288 | |
83d5e5b0 | 2289 | cleanup_srcu_struct(&md->io_barrier); |
86f1152b | 2290 | free_table_devices(&md->table_devices); |
63a4f065 | 2291 | dm_stats_cleanup(&md->stats); |
fba9f90e JM |
2292 | |
2293 | spin_lock(&_minor_lock); | |
2294 | md->disk->private_data = NULL; | |
2295 | spin_unlock(&_minor_lock); | |
63a4f065 MS |
2296 | if (blk_get_integrity(md->disk)) |
2297 | blk_integrity_unregister(md->disk); | |
2298 | del_gendisk(md->disk); | |
1da177e4 | 2299 | put_disk(md->disk); |
1312f40e | 2300 | blk_cleanup_queue(md->queue); |
63a4f065 MS |
2301 | bdput(md->bdev); |
2302 | free_minor(minor); | |
2303 | ||
10da4f79 | 2304 | module_put(THIS_MODULE); |
1da177e4 LT |
2305 | kfree(md); |
2306 | } | |
2307 | ||
e6ee8c0b KU |
2308 | static void __bind_mempools(struct mapped_device *md, struct dm_table *t) |
2309 | { | |
c0820cf5 | 2310 | struct dm_md_mempools *p = dm_table_get_md_mempools(t); |
e6ee8c0b | 2311 | |
5f015204 | 2312 | if (md->io_pool && md->bs) { |
16245bdc JN |
2313 | /* The md already has necessary mempools. */ |
2314 | if (dm_table_get_type(t) == DM_TYPE_BIO_BASED) { | |
2315 | /* | |
2316 | * Reload bioset because front_pad may have changed | |
2317 | * because a different table was loaded. | |
2318 | */ | |
2319 | bioset_free(md->bs); | |
2320 | md->bs = p->bs; | |
2321 | p->bs = NULL; | |
16245bdc | 2322 | } |
466d89a6 KB |
2323 | /* |
2324 | * There's no need to reload with request-based dm | |
2325 | * because the size of front_pad doesn't change. | |
2326 | * Note for future: If you are to reload bioset, | |
2327 | * prep-ed requests in the queue may refer | |
2328 | * to bio from the old bioset, so you must walk | |
2329 | * through the queue to unprep. | |
2330 | */ | |
e6ee8c0b | 2331 | goto out; |
c0820cf5 | 2332 | } |
e6ee8c0b | 2333 | |
1ae49ea2 | 2334 | BUG_ON(!p || md->io_pool || md->rq_pool || md->bs); |
e6ee8c0b KU |
2335 | |
2336 | md->io_pool = p->io_pool; | |
2337 | p->io_pool = NULL; | |
1ae49ea2 MS |
2338 | md->rq_pool = p->rq_pool; |
2339 | p->rq_pool = NULL; | |
e6ee8c0b KU |
2340 | md->bs = p->bs; |
2341 | p->bs = NULL; | |
2342 | ||
2343 | out: | |
2344 | /* mempool bind completed, now no need any mempools in the table */ | |
2345 | dm_table_free_md_mempools(t); | |
2346 | } | |
2347 | ||
1da177e4 LT |
2348 | /* |
2349 | * Bind a table to the device. | |
2350 | */ | |
2351 | static void event_callback(void *context) | |
2352 | { | |
7a8c3d3b MA |
2353 | unsigned long flags; |
2354 | LIST_HEAD(uevents); | |
1da177e4 LT |
2355 | struct mapped_device *md = (struct mapped_device *) context; |
2356 | ||
7a8c3d3b MA |
2357 | spin_lock_irqsave(&md->uevent_lock, flags); |
2358 | list_splice_init(&md->uevent_list, &uevents); | |
2359 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2360 | ||
ed9e1982 | 2361 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
7a8c3d3b | 2362 | |
1da177e4 LT |
2363 | atomic_inc(&md->event_nr); |
2364 | wake_up(&md->eventq); | |
2365 | } | |
2366 | ||
c217649b MS |
2367 | /* |
2368 | * Protected by md->suspend_lock obtained by dm_swap_table(). | |
2369 | */ | |
4e90188b | 2370 | static void __set_size(struct mapped_device *md, sector_t size) |
1da177e4 | 2371 | { |
4e90188b | 2372 | set_capacity(md->disk, size); |
1da177e4 | 2373 | |
db8fef4f | 2374 | i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
1da177e4 LT |
2375 | } |
2376 | ||
d5b9dd04 MP |
2377 | /* |
2378 | * Return 1 if the queue has a compulsory merge_bvec_fn function. | |
2379 | * | |
2380 | * If this function returns 0, then the device is either a non-dm | |
2381 | * device without a merge_bvec_fn, or it is a dm device that is | |
2382 | * able to split any bios it receives that are too big. | |
2383 | */ | |
2384 | int dm_queue_merge_is_compulsory(struct request_queue *q) | |
2385 | { | |
2386 | struct mapped_device *dev_md; | |
2387 | ||
2388 | if (!q->merge_bvec_fn) | |
2389 | return 0; | |
2390 | ||
ff36ab34 | 2391 | if (q->make_request_fn == dm_make_request) { |
d5b9dd04 MP |
2392 | dev_md = q->queuedata; |
2393 | if (test_bit(DMF_MERGE_IS_OPTIONAL, &dev_md->flags)) | |
2394 | return 0; | |
2395 | } | |
2396 | ||
2397 | return 1; | |
2398 | } | |
2399 | ||
2400 | static int dm_device_merge_is_compulsory(struct dm_target *ti, | |
2401 | struct dm_dev *dev, sector_t start, | |
2402 | sector_t len, void *data) | |
2403 | { | |
2404 | struct block_device *bdev = dev->bdev; | |
2405 | struct request_queue *q = bdev_get_queue(bdev); | |
2406 | ||
2407 | return dm_queue_merge_is_compulsory(q); | |
2408 | } | |
2409 | ||
2410 | /* | |
2411 | * Return 1 if it is acceptable to ignore merge_bvec_fn based | |
2412 | * on the properties of the underlying devices. | |
2413 | */ | |
2414 | static int dm_table_merge_is_optional(struct dm_table *table) | |
2415 | { | |
2416 | unsigned i = 0; | |
2417 | struct dm_target *ti; | |
2418 | ||
2419 | while (i < dm_table_get_num_targets(table)) { | |
2420 | ti = dm_table_get_target(table, i++); | |
2421 | ||
2422 | if (ti->type->iterate_devices && | |
2423 | ti->type->iterate_devices(ti, dm_device_merge_is_compulsory, NULL)) | |
2424 | return 0; | |
2425 | } | |
2426 | ||
2427 | return 1; | |
2428 | } | |
2429 | ||
042d2a9b AK |
2430 | /* |
2431 | * Returns old map, which caller must destroy. | |
2432 | */ | |
2433 | static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, | |
2434 | struct queue_limits *limits) | |
1da177e4 | 2435 | { |
042d2a9b | 2436 | struct dm_table *old_map; |
165125e1 | 2437 | struct request_queue *q = md->queue; |
1da177e4 | 2438 | sector_t size; |
d5b9dd04 | 2439 | int merge_is_optional; |
1da177e4 LT |
2440 | |
2441 | size = dm_table_get_size(t); | |
3ac51e74 DW |
2442 | |
2443 | /* | |
2444 | * Wipe any geometry if the size of the table changed. | |
2445 | */ | |
fd2ed4d2 | 2446 | if (size != dm_get_size(md)) |
3ac51e74 DW |
2447 | memset(&md->geometry, 0, sizeof(md->geometry)); |
2448 | ||
32a926da | 2449 | __set_size(md, size); |
d5816876 | 2450 | |
2ca3310e AK |
2451 | dm_table_event_callback(t, event_callback, md); |
2452 | ||
e6ee8c0b KU |
2453 | /* |
2454 | * The queue hasn't been stopped yet, if the old table type wasn't | |
2455 | * for request-based during suspension. So stop it to prevent | |
2456 | * I/O mapping before resume. | |
2457 | * This must be done before setting the queue restrictions, | |
2458 | * because request-based dm may be run just after the setting. | |
2459 | */ | |
2460 | if (dm_table_request_based(t) && !blk_queue_stopped(q)) | |
2461 | stop_queue(q); | |
2462 | ||
2463 | __bind_mempools(md, t); | |
2464 | ||
d5b9dd04 MP |
2465 | merge_is_optional = dm_table_merge_is_optional(t); |
2466 | ||
a12f5d48 | 2467 | old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
83d5e5b0 | 2468 | rcu_assign_pointer(md->map, t); |
36a0456f AK |
2469 | md->immutable_target_type = dm_table_get_immutable_target_type(t); |
2470 | ||
754c5fc7 | 2471 | dm_table_set_restrictions(t, q, limits); |
d5b9dd04 MP |
2472 | if (merge_is_optional) |
2473 | set_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
2474 | else | |
2475 | clear_bit(DMF_MERGE_IS_OPTIONAL, &md->flags); | |
41abc4e1 HR |
2476 | if (old_map) |
2477 | dm_sync_table(md); | |
1da177e4 | 2478 | |
042d2a9b | 2479 | return old_map; |
1da177e4 LT |
2480 | } |
2481 | ||
a7940155 AK |
2482 | /* |
2483 | * Returns unbound table for the caller to free. | |
2484 | */ | |
2485 | static struct dm_table *__unbind(struct mapped_device *md) | |
1da177e4 | 2486 | { |
a12f5d48 | 2487 | struct dm_table *map = rcu_dereference_protected(md->map, 1); |
1da177e4 LT |
2488 | |
2489 | if (!map) | |
a7940155 | 2490 | return NULL; |
1da177e4 LT |
2491 | |
2492 | dm_table_event_callback(map, NULL, NULL); | |
9cdb8520 | 2493 | RCU_INIT_POINTER(md->map, NULL); |
83d5e5b0 | 2494 | dm_sync_table(md); |
a7940155 AK |
2495 | |
2496 | return map; | |
1da177e4 LT |
2497 | } |
2498 | ||
2499 | /* | |
2500 | * Constructor for a new device. | |
2501 | */ | |
2b06cfff | 2502 | int dm_create(int minor, struct mapped_device **result) |
1da177e4 LT |
2503 | { |
2504 | struct mapped_device *md; | |
2505 | ||
2b06cfff | 2506 | md = alloc_dev(minor); |
1da177e4 LT |
2507 | if (!md) |
2508 | return -ENXIO; | |
2509 | ||
784aae73 MB |
2510 | dm_sysfs_init(md); |
2511 | ||
1da177e4 LT |
2512 | *result = md; |
2513 | return 0; | |
2514 | } | |
2515 | ||
a5664dad MS |
2516 | /* |
2517 | * Functions to manage md->type. | |
2518 | * All are required to hold md->type_lock. | |
2519 | */ | |
2520 | void dm_lock_md_type(struct mapped_device *md) | |
2521 | { | |
2522 | mutex_lock(&md->type_lock); | |
2523 | } | |
2524 | ||
2525 | void dm_unlock_md_type(struct mapped_device *md) | |
2526 | { | |
2527 | mutex_unlock(&md->type_lock); | |
2528 | } | |
2529 | ||
2530 | void dm_set_md_type(struct mapped_device *md, unsigned type) | |
2531 | { | |
00c4fc3b | 2532 | BUG_ON(!mutex_is_locked(&md->type_lock)); |
a5664dad MS |
2533 | md->type = type; |
2534 | } | |
2535 | ||
2536 | unsigned dm_get_md_type(struct mapped_device *md) | |
2537 | { | |
00c4fc3b | 2538 | BUG_ON(!mutex_is_locked(&md->type_lock)); |
a5664dad MS |
2539 | return md->type; |
2540 | } | |
2541 | ||
e5863d9a MS |
2542 | static bool dm_md_type_request_based(struct mapped_device *md) |
2543 | { | |
2544 | unsigned table_type = dm_get_md_type(md); | |
2545 | ||
2546 | return (table_type == DM_TYPE_REQUEST_BASED || | |
2547 | table_type == DM_TYPE_MQ_REQUEST_BASED); | |
2548 | } | |
2549 | ||
36a0456f AK |
2550 | struct target_type *dm_get_immutable_target_type(struct mapped_device *md) |
2551 | { | |
2552 | return md->immutable_target_type; | |
2553 | } | |
2554 | ||
f84cb8a4 MS |
2555 | /* |
2556 | * The queue_limits are only valid as long as you have a reference | |
2557 | * count on 'md'. | |
2558 | */ | |
2559 | struct queue_limits *dm_get_queue_limits(struct mapped_device *md) | |
2560 | { | |
2561 | BUG_ON(!atomic_read(&md->holders)); | |
2562 | return &md->queue->limits; | |
2563 | } | |
2564 | EXPORT_SYMBOL_GPL(dm_get_queue_limits); | |
2565 | ||
4a0b4ddf MS |
2566 | /* |
2567 | * Fully initialize a request-based queue (->elevator, ->request_fn, etc). | |
2568 | */ | |
2569 | static int dm_init_request_based_queue(struct mapped_device *md) | |
2570 | { | |
2571 | struct request_queue *q = NULL; | |
2572 | ||
2573 | if (md->queue->elevator) | |
2574 | return 1; | |
2575 | ||
2576 | /* Fully initialize the queue */ | |
2577 | q = blk_init_allocated_queue(md->queue, dm_request_fn, NULL); | |
2578 | if (!q) | |
2579 | return 0; | |
2580 | ||
0ce65797 MS |
2581 | /* disable dm_request_fn's merge heuristic by default */ |
2582 | md->seq_rq_merge_deadline_usecs = 0; | |
2583 | ||
4a0b4ddf | 2584 | md->queue = q; |
4a0b4ddf MS |
2585 | dm_init_md_queue(md); |
2586 | blk_queue_softirq_done(md->queue, dm_softirq_done); | |
2587 | blk_queue_prep_rq(md->queue, dm_prep_fn); | |
4a0b4ddf | 2588 | |
2eb6e1e3 KB |
2589 | /* Also initialize the request-based DM worker thread */ |
2590 | init_kthread_worker(&md->kworker); | |
2591 | md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker, | |
2592 | "kdmwork-%s", dm_device_name(md)); | |
2593 | ||
4a0b4ddf MS |
2594 | elv_register_queue(md->queue); |
2595 | ||
2596 | return 1; | |
2597 | } | |
2598 | ||
2599 | /* | |
2600 | * Setup the DM device's queue based on md's type | |
2601 | */ | |
2602 | int dm_setup_md_queue(struct mapped_device *md) | |
2603 | { | |
ff36ab34 MS |
2604 | if (dm_md_type_request_based(md)) { |
2605 | if (!dm_init_request_based_queue(md)) { | |
2606 | DMWARN("Cannot initialize queue for request-based mapped device"); | |
2607 | return -EINVAL; | |
2608 | } | |
2609 | } else { | |
2610 | /* bio-based specific initialization */ | |
2611 | blk_queue_make_request(md->queue, dm_make_request); | |
2612 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); | |
4a0b4ddf MS |
2613 | } |
2614 | ||
2615 | return 0; | |
2616 | } | |
2617 | ||
2bec1f4a | 2618 | struct mapped_device *dm_get_md(dev_t dev) |
1da177e4 LT |
2619 | { |
2620 | struct mapped_device *md; | |
1da177e4 LT |
2621 | unsigned minor = MINOR(dev); |
2622 | ||
2623 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
2624 | return NULL; | |
2625 | ||
f32c10b0 | 2626 | spin_lock(&_minor_lock); |
1da177e4 LT |
2627 | |
2628 | md = idr_find(&_minor_idr, minor); | |
2bec1f4a MP |
2629 | if (md) { |
2630 | if ((md == MINOR_ALLOCED || | |
2631 | (MINOR(disk_devt(dm_disk(md))) != minor) || | |
2632 | dm_deleting_md(md) || | |
2633 | test_bit(DMF_FREEING, &md->flags))) { | |
2634 | md = NULL; | |
2635 | goto out; | |
2636 | } | |
2637 | dm_get(md); | |
fba9f90e | 2638 | } |
1da177e4 | 2639 | |
fba9f90e | 2640 | out: |
f32c10b0 | 2641 | spin_unlock(&_minor_lock); |
1da177e4 | 2642 | |
637842cf DT |
2643 | return md; |
2644 | } | |
3cf2e4ba | 2645 | EXPORT_SYMBOL_GPL(dm_get_md); |
d229a958 | 2646 | |
9ade92a9 | 2647 | void *dm_get_mdptr(struct mapped_device *md) |
637842cf | 2648 | { |
9ade92a9 | 2649 | return md->interface_ptr; |
1da177e4 LT |
2650 | } |
2651 | ||
2652 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
2653 | { | |
2654 | md->interface_ptr = ptr; | |
2655 | } | |
2656 | ||
2657 | void dm_get(struct mapped_device *md) | |
2658 | { | |
2659 | atomic_inc(&md->holders); | |
3f77316d | 2660 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
1da177e4 LT |
2661 | } |
2662 | ||
09ee96b2 MP |
2663 | int dm_hold(struct mapped_device *md) |
2664 | { | |
2665 | spin_lock(&_minor_lock); | |
2666 | if (test_bit(DMF_FREEING, &md->flags)) { | |
2667 | spin_unlock(&_minor_lock); | |
2668 | return -EBUSY; | |
2669 | } | |
2670 | dm_get(md); | |
2671 | spin_unlock(&_minor_lock); | |
2672 | return 0; | |
2673 | } | |
2674 | EXPORT_SYMBOL_GPL(dm_hold); | |
2675 | ||
72d94861 AK |
2676 | const char *dm_device_name(struct mapped_device *md) |
2677 | { | |
2678 | return md->name; | |
2679 | } | |
2680 | EXPORT_SYMBOL_GPL(dm_device_name); | |
2681 | ||
3f77316d | 2682 | static void __dm_destroy(struct mapped_device *md, bool wait) |
1da177e4 | 2683 | { |
1134e5ae | 2684 | struct dm_table *map; |
83d5e5b0 | 2685 | int srcu_idx; |
1da177e4 | 2686 | |
3f77316d | 2687 | might_sleep(); |
fba9f90e | 2688 | |
83d5e5b0 | 2689 | map = dm_get_live_table(md, &srcu_idx); |
63a4f065 MS |
2690 | |
2691 | spin_lock(&_minor_lock); | |
3f77316d KU |
2692 | idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); |
2693 | set_bit(DMF_FREEING, &md->flags); | |
2694 | spin_unlock(&_minor_lock); | |
2695 | ||
2eb6e1e3 KB |
2696 | if (dm_request_based(md)) |
2697 | flush_kthread_worker(&md->kworker); | |
2698 | ||
ab7c7bb6 MP |
2699 | /* |
2700 | * Take suspend_lock so that presuspend and postsuspend methods | |
2701 | * do not race with internal suspend. | |
2702 | */ | |
2703 | mutex_lock(&md->suspend_lock); | |
3f77316d KU |
2704 | if (!dm_suspended_md(md)) { |
2705 | dm_table_presuspend_targets(map); | |
2706 | dm_table_postsuspend_targets(map); | |
1da177e4 | 2707 | } |
ab7c7bb6 | 2708 | mutex_unlock(&md->suspend_lock); |
3f77316d | 2709 | |
83d5e5b0 MP |
2710 | /* dm_put_live_table must be before msleep, otherwise deadlock is possible */ |
2711 | dm_put_live_table(md, srcu_idx); | |
2712 | ||
3f77316d KU |
2713 | /* |
2714 | * Rare, but there may be I/O requests still going to complete, | |
2715 | * for example. Wait for all references to disappear. | |
2716 | * No one should increment the reference count of the mapped_device, | |
2717 | * after the mapped_device state becomes DMF_FREEING. | |
2718 | */ | |
2719 | if (wait) | |
2720 | while (atomic_read(&md->holders)) | |
2721 | msleep(1); | |
2722 | else if (atomic_read(&md->holders)) | |
2723 | DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", | |
2724 | dm_device_name(md), atomic_read(&md->holders)); | |
2725 | ||
2726 | dm_sysfs_exit(md); | |
3f77316d KU |
2727 | dm_table_destroy(__unbind(md)); |
2728 | free_dev(md); | |
2729 | } | |
2730 | ||
2731 | void dm_destroy(struct mapped_device *md) | |
2732 | { | |
2733 | __dm_destroy(md, true); | |
2734 | } | |
2735 | ||
2736 | void dm_destroy_immediate(struct mapped_device *md) | |
2737 | { | |
2738 | __dm_destroy(md, false); | |
2739 | } | |
2740 | ||
2741 | void dm_put(struct mapped_device *md) | |
2742 | { | |
2743 | atomic_dec(&md->holders); | |
1da177e4 | 2744 | } |
79eb885c | 2745 | EXPORT_SYMBOL_GPL(dm_put); |
1da177e4 | 2746 | |
401600df | 2747 | static int dm_wait_for_completion(struct mapped_device *md, int interruptible) |
46125c1c MB |
2748 | { |
2749 | int r = 0; | |
b44ebeb0 MP |
2750 | DECLARE_WAITQUEUE(wait, current); |
2751 | ||
b44ebeb0 | 2752 | add_wait_queue(&md->wait, &wait); |
46125c1c MB |
2753 | |
2754 | while (1) { | |
401600df | 2755 | set_current_state(interruptible); |
46125c1c | 2756 | |
b4324fee | 2757 | if (!md_in_flight(md)) |
46125c1c MB |
2758 | break; |
2759 | ||
401600df MP |
2760 | if (interruptible == TASK_INTERRUPTIBLE && |
2761 | signal_pending(current)) { | |
46125c1c MB |
2762 | r = -EINTR; |
2763 | break; | |
2764 | } | |
2765 | ||
2766 | io_schedule(); | |
2767 | } | |
2768 | set_current_state(TASK_RUNNING); | |
2769 | ||
b44ebeb0 MP |
2770 | remove_wait_queue(&md->wait, &wait); |
2771 | ||
46125c1c MB |
2772 | return r; |
2773 | } | |
2774 | ||
1da177e4 LT |
2775 | /* |
2776 | * Process the deferred bios | |
2777 | */ | |
ef208587 | 2778 | static void dm_wq_work(struct work_struct *work) |
1da177e4 | 2779 | { |
ef208587 MP |
2780 | struct mapped_device *md = container_of(work, struct mapped_device, |
2781 | work); | |
6d6f10df | 2782 | struct bio *c; |
83d5e5b0 MP |
2783 | int srcu_idx; |
2784 | struct dm_table *map; | |
1da177e4 | 2785 | |
83d5e5b0 | 2786 | map = dm_get_live_table(md, &srcu_idx); |
ef208587 | 2787 | |
3b00b203 | 2788 | while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
df12ee99 AK |
2789 | spin_lock_irq(&md->deferred_lock); |
2790 | c = bio_list_pop(&md->deferred); | |
2791 | spin_unlock_irq(&md->deferred_lock); | |
2792 | ||
6a8736d1 | 2793 | if (!c) |
df12ee99 | 2794 | break; |
022c2611 | 2795 | |
e6ee8c0b KU |
2796 | if (dm_request_based(md)) |
2797 | generic_make_request(c); | |
6a8736d1 | 2798 | else |
83d5e5b0 | 2799 | __split_and_process_bio(md, map, c); |
022c2611 | 2800 | } |
73d410c0 | 2801 | |
83d5e5b0 | 2802 | dm_put_live_table(md, srcu_idx); |
1da177e4 LT |
2803 | } |
2804 | ||
9a1fb464 | 2805 | static void dm_queue_flush(struct mapped_device *md) |
304f3f6a | 2806 | { |
3b00b203 | 2807 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
4e857c58 | 2808 | smp_mb__after_atomic(); |
53d5914f | 2809 | queue_work(md->wq, &md->work); |
304f3f6a MB |
2810 | } |
2811 | ||
1da177e4 | 2812 | /* |
042d2a9b | 2813 | * Swap in a new table, returning the old one for the caller to destroy. |
1da177e4 | 2814 | */ |
042d2a9b | 2815 | struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) |
1da177e4 | 2816 | { |
87eb5b21 | 2817 | struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL); |
754c5fc7 | 2818 | struct queue_limits limits; |
042d2a9b | 2819 | int r; |
1da177e4 | 2820 | |
e61290a4 | 2821 | mutex_lock(&md->suspend_lock); |
1da177e4 LT |
2822 | |
2823 | /* device must be suspended */ | |
4f186f8b | 2824 | if (!dm_suspended_md(md)) |
93c534ae | 2825 | goto out; |
1da177e4 | 2826 | |
3ae70656 MS |
2827 | /* |
2828 | * If the new table has no data devices, retain the existing limits. | |
2829 | * This helps multipath with queue_if_no_path if all paths disappear, | |
2830 | * then new I/O is queued based on these limits, and then some paths | |
2831 | * reappear. | |
2832 | */ | |
2833 | if (dm_table_has_no_data_devices(table)) { | |
83d5e5b0 | 2834 | live_map = dm_get_live_table_fast(md); |
3ae70656 MS |
2835 | if (live_map) |
2836 | limits = md->queue->limits; | |
83d5e5b0 | 2837 | dm_put_live_table_fast(md); |
3ae70656 MS |
2838 | } |
2839 | ||
87eb5b21 MC |
2840 | if (!live_map) { |
2841 | r = dm_calculate_queue_limits(table, &limits); | |
2842 | if (r) { | |
2843 | map = ERR_PTR(r); | |
2844 | goto out; | |
2845 | } | |
042d2a9b | 2846 | } |
754c5fc7 | 2847 | |
042d2a9b | 2848 | map = __bind(md, table, &limits); |
1da177e4 | 2849 | |
93c534ae | 2850 | out: |
e61290a4 | 2851 | mutex_unlock(&md->suspend_lock); |
042d2a9b | 2852 | return map; |
1da177e4 LT |
2853 | } |
2854 | ||
2855 | /* | |
2856 | * Functions to lock and unlock any filesystem running on the | |
2857 | * device. | |
2858 | */ | |
2ca3310e | 2859 | static int lock_fs(struct mapped_device *md) |
1da177e4 | 2860 | { |
e39e2e95 | 2861 | int r; |
1da177e4 LT |
2862 | |
2863 | WARN_ON(md->frozen_sb); | |
dfbe03f6 | 2864 | |
db8fef4f | 2865 | md->frozen_sb = freeze_bdev(md->bdev); |
dfbe03f6 | 2866 | if (IS_ERR(md->frozen_sb)) { |
cf222b37 | 2867 | r = PTR_ERR(md->frozen_sb); |
e39e2e95 AK |
2868 | md->frozen_sb = NULL; |
2869 | return r; | |
dfbe03f6 AK |
2870 | } |
2871 | ||
aa8d7c2f AK |
2872 | set_bit(DMF_FROZEN, &md->flags); |
2873 | ||
1da177e4 LT |
2874 | return 0; |
2875 | } | |
2876 | ||
2ca3310e | 2877 | static void unlock_fs(struct mapped_device *md) |
1da177e4 | 2878 | { |
aa8d7c2f AK |
2879 | if (!test_bit(DMF_FROZEN, &md->flags)) |
2880 | return; | |
2881 | ||
db8fef4f | 2882 | thaw_bdev(md->bdev, md->frozen_sb); |
1da177e4 | 2883 | md->frozen_sb = NULL; |
aa8d7c2f | 2884 | clear_bit(DMF_FROZEN, &md->flags); |
1da177e4 LT |
2885 | } |
2886 | ||
2887 | /* | |
ffcc3936 MS |
2888 | * If __dm_suspend returns 0, the device is completely quiescent |
2889 | * now. There is no request-processing activity. All new requests | |
2890 | * are being added to md->deferred list. | |
cec47e3d | 2891 | * |
ffcc3936 | 2892 | * Caller must hold md->suspend_lock |
cec47e3d | 2893 | */ |
ffcc3936 MS |
2894 | static int __dm_suspend(struct mapped_device *md, struct dm_table *map, |
2895 | unsigned suspend_flags, int interruptible) | |
1da177e4 | 2896 | { |
ffcc3936 MS |
2897 | bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG; |
2898 | bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG; | |
2899 | int r; | |
1da177e4 | 2900 | |
2e93ccc1 KU |
2901 | /* |
2902 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
2903 | * This flag is cleared before dm_suspend returns. | |
2904 | */ | |
2905 | if (noflush) | |
2906 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
2907 | ||
d67ee213 MS |
2908 | /* |
2909 | * This gets reverted if there's an error later and the targets | |
2910 | * provide the .presuspend_undo hook. | |
2911 | */ | |
cf222b37 AK |
2912 | dm_table_presuspend_targets(map); |
2913 | ||
32a926da | 2914 | /* |
9f518b27 KU |
2915 | * Flush I/O to the device. |
2916 | * Any I/O submitted after lock_fs() may not be flushed. | |
2917 | * noflush takes precedence over do_lockfs. | |
2918 | * (lock_fs() flushes I/Os and waits for them to complete.) | |
32a926da MP |
2919 | */ |
2920 | if (!noflush && do_lockfs) { | |
2921 | r = lock_fs(md); | |
d67ee213 MS |
2922 | if (r) { |
2923 | dm_table_presuspend_undo_targets(map); | |
ffcc3936 | 2924 | return r; |
d67ee213 | 2925 | } |
aa8d7c2f | 2926 | } |
1da177e4 LT |
2927 | |
2928 | /* | |
3b00b203 MP |
2929 | * Here we must make sure that no processes are submitting requests |
2930 | * to target drivers i.e. no one may be executing | |
2931 | * __split_and_process_bio. This is called from dm_request and | |
2932 | * dm_wq_work. | |
2933 | * | |
2934 | * To get all processes out of __split_and_process_bio in dm_request, | |
2935 | * we take the write lock. To prevent any process from reentering | |
6a8736d1 TH |
2936 | * __split_and_process_bio from dm_request and quiesce the thread |
2937 | * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call | |
2938 | * flush_workqueue(md->wq). | |
1da177e4 | 2939 | */ |
1eb787ec | 2940 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
41abc4e1 HR |
2941 | if (map) |
2942 | synchronize_srcu(&md->io_barrier); | |
1da177e4 | 2943 | |
d0bcb878 | 2944 | /* |
29e4013d TH |
2945 | * Stop md->queue before flushing md->wq in case request-based |
2946 | * dm defers requests to md->wq from md->queue. | |
d0bcb878 | 2947 | */ |
2eb6e1e3 | 2948 | if (dm_request_based(md)) { |
9f518b27 | 2949 | stop_queue(md->queue); |
2eb6e1e3 KB |
2950 | flush_kthread_worker(&md->kworker); |
2951 | } | |
cec47e3d | 2952 | |
d0bcb878 KU |
2953 | flush_workqueue(md->wq); |
2954 | ||
1da177e4 | 2955 | /* |
3b00b203 MP |
2956 | * At this point no more requests are entering target request routines. |
2957 | * We call dm_wait_for_completion to wait for all existing requests | |
2958 | * to finish. | |
1da177e4 | 2959 | */ |
ffcc3936 | 2960 | r = dm_wait_for_completion(md, interruptible); |
1da177e4 | 2961 | |
6d6f10df | 2962 | if (noflush) |
022c2611 | 2963 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
41abc4e1 HR |
2964 | if (map) |
2965 | synchronize_srcu(&md->io_barrier); | |
2e93ccc1 | 2966 | |
1da177e4 | 2967 | /* were we interrupted ? */ |
46125c1c | 2968 | if (r < 0) { |
9a1fb464 | 2969 | dm_queue_flush(md); |
73d410c0 | 2970 | |
cec47e3d | 2971 | if (dm_request_based(md)) |
9f518b27 | 2972 | start_queue(md->queue); |
cec47e3d | 2973 | |
2ca3310e | 2974 | unlock_fs(md); |
d67ee213 | 2975 | dm_table_presuspend_undo_targets(map); |
ffcc3936 | 2976 | /* pushback list is already flushed, so skip flush */ |
2ca3310e | 2977 | } |
1da177e4 | 2978 | |
ffcc3936 MS |
2979 | return r; |
2980 | } | |
2981 | ||
2982 | /* | |
2983 | * We need to be able to change a mapping table under a mounted | |
2984 | * filesystem. For example we might want to move some data in | |
2985 | * the background. Before the table can be swapped with | |
2986 | * dm_bind_table, dm_suspend must be called to flush any in | |
2987 | * flight bios and ensure that any further io gets deferred. | |
2988 | */ | |
2989 | /* | |
2990 | * Suspend mechanism in request-based dm. | |
2991 | * | |
2992 | * 1. Flush all I/Os by lock_fs() if needed. | |
2993 | * 2. Stop dispatching any I/O by stopping the request_queue. | |
2994 | * 3. Wait for all in-flight I/Os to be completed or requeued. | |
2995 | * | |
2996 | * To abort suspend, start the request_queue. | |
2997 | */ | |
2998 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) | |
2999 | { | |
3000 | struct dm_table *map = NULL; | |
3001 | int r = 0; | |
3002 | ||
3003 | retry: | |
3004 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
3005 | ||
3006 | if (dm_suspended_md(md)) { | |
3007 | r = -EINVAL; | |
3008 | goto out_unlock; | |
3009 | } | |
3010 | ||
3011 | if (dm_suspended_internally_md(md)) { | |
3012 | /* already internally suspended, wait for internal resume */ | |
3013 | mutex_unlock(&md->suspend_lock); | |
3014 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
3015 | if (r) | |
3016 | return r; | |
3017 | goto retry; | |
3018 | } | |
3019 | ||
a12f5d48 | 3020 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
ffcc3936 MS |
3021 | |
3022 | r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE); | |
3023 | if (r) | |
3024 | goto out_unlock; | |
3b00b203 | 3025 | |
2ca3310e | 3026 | set_bit(DMF_SUSPENDED, &md->flags); |
b84b0287 | 3027 | |
4d4471cb KU |
3028 | dm_table_postsuspend_targets(map); |
3029 | ||
d287483d | 3030 | out_unlock: |
e61290a4 | 3031 | mutex_unlock(&md->suspend_lock); |
cf222b37 | 3032 | return r; |
1da177e4 LT |
3033 | } |
3034 | ||
ffcc3936 MS |
3035 | static int __dm_resume(struct mapped_device *md, struct dm_table *map) |
3036 | { | |
3037 | if (map) { | |
3038 | int r = dm_table_resume_targets(map); | |
3039 | if (r) | |
3040 | return r; | |
3041 | } | |
3042 | ||
3043 | dm_queue_flush(md); | |
3044 | ||
3045 | /* | |
3046 | * Flushing deferred I/Os must be done after targets are resumed | |
3047 | * so that mapping of targets can work correctly. | |
3048 | * Request-based dm is queueing the deferred I/Os in its request_queue. | |
3049 | */ | |
3050 | if (dm_request_based(md)) | |
3051 | start_queue(md->queue); | |
3052 | ||
3053 | unlock_fs(md); | |
3054 | ||
3055 | return 0; | |
3056 | } | |
3057 | ||
1da177e4 LT |
3058 | int dm_resume(struct mapped_device *md) |
3059 | { | |
cf222b37 | 3060 | int r = -EINVAL; |
cf222b37 | 3061 | struct dm_table *map = NULL; |
1da177e4 | 3062 | |
ffcc3936 MS |
3063 | retry: |
3064 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
3065 | ||
4f186f8b | 3066 | if (!dm_suspended_md(md)) |
cf222b37 | 3067 | goto out; |
cf222b37 | 3068 | |
ffcc3936 MS |
3069 | if (dm_suspended_internally_md(md)) { |
3070 | /* already internally suspended, wait for internal resume */ | |
3071 | mutex_unlock(&md->suspend_lock); | |
3072 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
3073 | if (r) | |
3074 | return r; | |
3075 | goto retry; | |
3076 | } | |
3077 | ||
a12f5d48 | 3078 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
2ca3310e | 3079 | if (!map || !dm_table_get_size(map)) |
cf222b37 | 3080 | goto out; |
1da177e4 | 3081 | |
ffcc3936 | 3082 | r = __dm_resume(md, map); |
8757b776 MB |
3083 | if (r) |
3084 | goto out; | |
2ca3310e | 3085 | |
2ca3310e AK |
3086 | clear_bit(DMF_SUSPENDED, &md->flags); |
3087 | ||
cf222b37 AK |
3088 | r = 0; |
3089 | out: | |
e61290a4 | 3090 | mutex_unlock(&md->suspend_lock); |
2ca3310e | 3091 | |
cf222b37 | 3092 | return r; |
1da177e4 LT |
3093 | } |
3094 | ||
fd2ed4d2 MP |
3095 | /* |
3096 | * Internal suspend/resume works like userspace-driven suspend. It waits | |
3097 | * until all bios finish and prevents issuing new bios to the target drivers. | |
3098 | * It may be used only from the kernel. | |
fd2ed4d2 MP |
3099 | */ |
3100 | ||
ffcc3936 | 3101 | static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags) |
fd2ed4d2 | 3102 | { |
ffcc3936 MS |
3103 | struct dm_table *map = NULL; |
3104 | ||
96b26c8c | 3105 | if (md->internal_suspend_count++) |
ffcc3936 MS |
3106 | return; /* nested internal suspend */ |
3107 | ||
3108 | if (dm_suspended_md(md)) { | |
3109 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3110 | return; /* nest suspend */ | |
3111 | } | |
3112 | ||
a12f5d48 | 3113 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
ffcc3936 MS |
3114 | |
3115 | /* | |
3116 | * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is | |
3117 | * supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend | |
3118 | * would require changing .presuspend to return an error -- avoid this | |
3119 | * until there is a need for more elaborate variants of internal suspend. | |
3120 | */ | |
3121 | (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE); | |
3122 | ||
3123 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3124 | ||
3125 | dm_table_postsuspend_targets(map); | |
3126 | } | |
3127 | ||
3128 | static void __dm_internal_resume(struct mapped_device *md) | |
3129 | { | |
96b26c8c MP |
3130 | BUG_ON(!md->internal_suspend_count); |
3131 | ||
3132 | if (--md->internal_suspend_count) | |
ffcc3936 MS |
3133 | return; /* resume from nested internal suspend */ |
3134 | ||
fd2ed4d2 | 3135 | if (dm_suspended_md(md)) |
ffcc3936 MS |
3136 | goto done; /* resume from nested suspend */ |
3137 | ||
3138 | /* | |
3139 | * NOTE: existing callers don't need to call dm_table_resume_targets | |
3140 | * (which may fail -- so best to avoid it for now by passing NULL map) | |
3141 | */ | |
3142 | (void) __dm_resume(md, NULL); | |
3143 | ||
3144 | done: | |
3145 | clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3146 | smp_mb__after_atomic(); | |
3147 | wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY); | |
3148 | } | |
3149 | ||
3150 | void dm_internal_suspend_noflush(struct mapped_device *md) | |
3151 | { | |
3152 | mutex_lock(&md->suspend_lock); | |
3153 | __dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG); | |
3154 | mutex_unlock(&md->suspend_lock); | |
3155 | } | |
3156 | EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush); | |
3157 | ||
3158 | void dm_internal_resume(struct mapped_device *md) | |
3159 | { | |
3160 | mutex_lock(&md->suspend_lock); | |
3161 | __dm_internal_resume(md); | |
3162 | mutex_unlock(&md->suspend_lock); | |
3163 | } | |
3164 | EXPORT_SYMBOL_GPL(dm_internal_resume); | |
3165 | ||
3166 | /* | |
3167 | * Fast variants of internal suspend/resume hold md->suspend_lock, | |
3168 | * which prevents interaction with userspace-driven suspend. | |
3169 | */ | |
3170 | ||
3171 | void dm_internal_suspend_fast(struct mapped_device *md) | |
3172 | { | |
3173 | mutex_lock(&md->suspend_lock); | |
3174 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) | |
fd2ed4d2 MP |
3175 | return; |
3176 | ||
3177 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); | |
3178 | synchronize_srcu(&md->io_barrier); | |
3179 | flush_workqueue(md->wq); | |
3180 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); | |
3181 | } | |
b735fede | 3182 | EXPORT_SYMBOL_GPL(dm_internal_suspend_fast); |
fd2ed4d2 | 3183 | |
ffcc3936 | 3184 | void dm_internal_resume_fast(struct mapped_device *md) |
fd2ed4d2 | 3185 | { |
ffcc3936 | 3186 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) |
fd2ed4d2 MP |
3187 | goto done; |
3188 | ||
3189 | dm_queue_flush(md); | |
3190 | ||
3191 | done: | |
3192 | mutex_unlock(&md->suspend_lock); | |
3193 | } | |
b735fede | 3194 | EXPORT_SYMBOL_GPL(dm_internal_resume_fast); |
fd2ed4d2 | 3195 | |
1da177e4 LT |
3196 | /*----------------------------------------------------------------- |
3197 | * Event notification. | |
3198 | *---------------------------------------------------------------*/ | |
3abf85b5 | 3199 | int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
60935eb2 | 3200 | unsigned cookie) |
69267a30 | 3201 | { |
60935eb2 MB |
3202 | char udev_cookie[DM_COOKIE_LENGTH]; |
3203 | char *envp[] = { udev_cookie, NULL }; | |
3204 | ||
3205 | if (!cookie) | |
3abf85b5 | 3206 | return kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
60935eb2 MB |
3207 | else { |
3208 | snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", | |
3209 | DM_COOKIE_ENV_VAR_NAME, cookie); | |
3abf85b5 PR |
3210 | return kobject_uevent_env(&disk_to_dev(md->disk)->kobj, |
3211 | action, envp); | |
60935eb2 | 3212 | } |
69267a30 AK |
3213 | } |
3214 | ||
7a8c3d3b MA |
3215 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
3216 | { | |
3217 | return atomic_add_return(1, &md->uevent_seq); | |
3218 | } | |
3219 | ||
1da177e4 LT |
3220 | uint32_t dm_get_event_nr(struct mapped_device *md) |
3221 | { | |
3222 | return atomic_read(&md->event_nr); | |
3223 | } | |
3224 | ||
3225 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
3226 | { | |
3227 | return wait_event_interruptible(md->eventq, | |
3228 | (event_nr != atomic_read(&md->event_nr))); | |
3229 | } | |
3230 | ||
7a8c3d3b MA |
3231 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
3232 | { | |
3233 | unsigned long flags; | |
3234 | ||
3235 | spin_lock_irqsave(&md->uevent_lock, flags); | |
3236 | list_add(elist, &md->uevent_list); | |
3237 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
3238 | } | |
3239 | ||
1da177e4 LT |
3240 | /* |
3241 | * The gendisk is only valid as long as you have a reference | |
3242 | * count on 'md'. | |
3243 | */ | |
3244 | struct gendisk *dm_disk(struct mapped_device *md) | |
3245 | { | |
3246 | return md->disk; | |
3247 | } | |
3248 | ||
784aae73 MB |
3249 | struct kobject *dm_kobject(struct mapped_device *md) |
3250 | { | |
2995fa78 | 3251 | return &md->kobj_holder.kobj; |
784aae73 MB |
3252 | } |
3253 | ||
784aae73 MB |
3254 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) |
3255 | { | |
3256 | struct mapped_device *md; | |
3257 | ||
2995fa78 | 3258 | md = container_of(kobj, struct mapped_device, kobj_holder.kobj); |
784aae73 | 3259 | |
4d89b7b4 | 3260 | if (test_bit(DMF_FREEING, &md->flags) || |
432a212c | 3261 | dm_deleting_md(md)) |
4d89b7b4 MB |
3262 | return NULL; |
3263 | ||
784aae73 MB |
3264 | dm_get(md); |
3265 | return md; | |
3266 | } | |
3267 | ||
4f186f8b | 3268 | int dm_suspended_md(struct mapped_device *md) |
1da177e4 LT |
3269 | { |
3270 | return test_bit(DMF_SUSPENDED, &md->flags); | |
3271 | } | |
3272 | ||
ffcc3936 MS |
3273 | int dm_suspended_internally_md(struct mapped_device *md) |
3274 | { | |
3275 | return test_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
3276 | } | |
3277 | ||
2c140a24 MP |
3278 | int dm_test_deferred_remove_flag(struct mapped_device *md) |
3279 | { | |
3280 | return test_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
3281 | } | |
3282 | ||
64dbce58 KU |
3283 | int dm_suspended(struct dm_target *ti) |
3284 | { | |
ecdb2e25 | 3285 | return dm_suspended_md(dm_table_get_md(ti->table)); |
64dbce58 KU |
3286 | } |
3287 | EXPORT_SYMBOL_GPL(dm_suspended); | |
3288 | ||
2e93ccc1 KU |
3289 | int dm_noflush_suspending(struct dm_target *ti) |
3290 | { | |
ecdb2e25 | 3291 | return __noflush_suspending(dm_table_get_md(ti->table)); |
2e93ccc1 KU |
3292 | } |
3293 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
3294 | ||
c0820cf5 | 3295 | struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, unsigned per_bio_data_size) |
e6ee8c0b | 3296 | { |
5f015204 JN |
3297 | struct dm_md_mempools *pools = kzalloc(sizeof(*pools), GFP_KERNEL); |
3298 | struct kmem_cache *cachep; | |
e5863d9a | 3299 | unsigned int pool_size = 0; |
5f015204 | 3300 | unsigned int front_pad; |
e6ee8c0b KU |
3301 | |
3302 | if (!pools) | |
3303 | return NULL; | |
3304 | ||
e5863d9a MS |
3305 | switch (type) { |
3306 | case DM_TYPE_BIO_BASED: | |
5f015204 | 3307 | cachep = _io_cache; |
e8603136 | 3308 | pool_size = dm_get_reserved_bio_based_ios(); |
5f015204 | 3309 | front_pad = roundup(per_bio_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone); |
e5863d9a MS |
3310 | break; |
3311 | case DM_TYPE_REQUEST_BASED: | |
f4790826 | 3312 | pool_size = dm_get_reserved_rq_based_ios(); |
1ae49ea2 MS |
3313 | pools->rq_pool = mempool_create_slab_pool(pool_size, _rq_cache); |
3314 | if (!pools->rq_pool) | |
3315 | goto out; | |
e5863d9a MS |
3316 | /* fall through to setup remaining rq-based pools */ |
3317 | case DM_TYPE_MQ_REQUEST_BASED: | |
3318 | cachep = _rq_tio_cache; | |
3319 | if (!pool_size) | |
3320 | pool_size = dm_get_reserved_rq_based_ios(); | |
5f015204 JN |
3321 | front_pad = offsetof(struct dm_rq_clone_bio_info, clone); |
3322 | /* per_bio_data_size is not used. See __bind_mempools(). */ | |
3323 | WARN_ON(per_bio_data_size != 0); | |
e5863d9a MS |
3324 | break; |
3325 | default: | |
5f015204 | 3326 | goto out; |
e5863d9a | 3327 | } |
e6ee8c0b | 3328 | |
6cfa5857 | 3329 | pools->io_pool = mempool_create_slab_pool(pool_size, cachep); |
5f015204 JN |
3330 | if (!pools->io_pool) |
3331 | goto out; | |
e6ee8c0b | 3332 | |
3d8aab2d | 3333 | pools->bs = bioset_create_nobvec(pool_size, front_pad); |
e6ee8c0b | 3334 | if (!pools->bs) |
5f015204 | 3335 | goto out; |
e6ee8c0b | 3336 | |
a91a2785 | 3337 | if (integrity && bioset_integrity_create(pools->bs, pool_size)) |
5f015204 | 3338 | goto out; |
a91a2785 | 3339 | |
e6ee8c0b KU |
3340 | return pools; |
3341 | ||
5f015204 JN |
3342 | out: |
3343 | dm_free_md_mempools(pools); | |
e6ee8c0b KU |
3344 | |
3345 | return NULL; | |
3346 | } | |
3347 | ||
3348 | void dm_free_md_mempools(struct dm_md_mempools *pools) | |
3349 | { | |
3350 | if (!pools) | |
3351 | return; | |
3352 | ||
3353 | if (pools->io_pool) | |
3354 | mempool_destroy(pools->io_pool); | |
3355 | ||
1ae49ea2 MS |
3356 | if (pools->rq_pool) |
3357 | mempool_destroy(pools->rq_pool); | |
3358 | ||
e6ee8c0b KU |
3359 | if (pools->bs) |
3360 | bioset_free(pools->bs); | |
3361 | ||
3362 | kfree(pools); | |
3363 | } | |
3364 | ||
83d5cde4 | 3365 | static const struct block_device_operations dm_blk_dops = { |
1da177e4 LT |
3366 | .open = dm_blk_open, |
3367 | .release = dm_blk_close, | |
aa129a22 | 3368 | .ioctl = dm_blk_ioctl, |
3ac51e74 | 3369 | .getgeo = dm_blk_getgeo, |
1da177e4 LT |
3370 | .owner = THIS_MODULE |
3371 | }; | |
3372 | ||
1da177e4 LT |
3373 | /* |
3374 | * module hooks | |
3375 | */ | |
3376 | module_init(dm_init); | |
3377 | module_exit(dm_exit); | |
3378 | ||
3379 | module_param(major, uint, 0); | |
3380 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
f4790826 | 3381 | |
e8603136 MS |
3382 | module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR); |
3383 | MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools"); | |
3384 | ||
f4790826 MS |
3385 | module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR); |
3386 | MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools"); | |
3387 | ||
1da177e4 LT |
3388 | MODULE_DESCRIPTION(DM_NAME " driver"); |
3389 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
3390 | MODULE_LICENSE("GPL"); |