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1 | /* | |
2 | * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. | |
3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. | |
4 | * | |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include "dm-core.h" | |
9 | #include "dm-rq.h" | |
10 | #include "dm-uevent.h" | |
11 | ||
12 | #include <linux/init.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/mutex.h> | |
15 | #include <linux/sched/signal.h> | |
16 | #include <linux/blkpg.h> | |
17 | #include <linux/bio.h> | |
18 | #include <linux/mempool.h> | |
19 | #include <linux/dax.h> | |
20 | #include <linux/slab.h> | |
21 | #include <linux/idr.h> | |
22 | #include <linux/uio.h> | |
23 | #include <linux/hdreg.h> | |
24 | #include <linux/delay.h> | |
25 | #include <linux/wait.h> | |
26 | #include <linux/pr.h> | |
27 | #include <linux/refcount.h> | |
28 | ||
29 | #define DM_MSG_PREFIX "core" | |
30 | ||
31 | /* | |
32 | * Cookies are numeric values sent with CHANGE and REMOVE | |
33 | * uevents while resuming, removing or renaming the device. | |
34 | */ | |
35 | #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" | |
36 | #define DM_COOKIE_LENGTH 24 | |
37 | ||
38 | static const char *_name = DM_NAME; | |
39 | ||
40 | static unsigned int major = 0; | |
41 | static unsigned int _major = 0; | |
42 | ||
43 | static DEFINE_IDR(_minor_idr); | |
44 | ||
45 | static DEFINE_SPINLOCK(_minor_lock); | |
46 | ||
47 | static void do_deferred_remove(struct work_struct *w); | |
48 | ||
49 | static DECLARE_WORK(deferred_remove_work, do_deferred_remove); | |
50 | ||
51 | static struct workqueue_struct *deferred_remove_workqueue; | |
52 | ||
53 | atomic_t dm_global_event_nr = ATOMIC_INIT(0); | |
54 | DECLARE_WAIT_QUEUE_HEAD(dm_global_eventq); | |
55 | ||
56 | void dm_issue_global_event(void) | |
57 | { | |
58 | atomic_inc(&dm_global_event_nr); | |
59 | wake_up(&dm_global_eventq); | |
60 | } | |
61 | ||
62 | /* | |
63 | * One of these is allocated (on-stack) per original bio. | |
64 | */ | |
65 | struct clone_info { | |
66 | struct dm_table *map; | |
67 | struct bio *bio; | |
68 | struct dm_io *io; | |
69 | sector_t sector; | |
70 | unsigned sector_count; | |
71 | }; | |
72 | ||
73 | /* | |
74 | * One of these is allocated per clone bio. | |
75 | */ | |
76 | #define DM_TIO_MAGIC 7282014 | |
77 | struct dm_target_io { | |
78 | unsigned magic; | |
79 | struct dm_io *io; | |
80 | struct dm_target *ti; | |
81 | unsigned target_bio_nr; | |
82 | unsigned *len_ptr; | |
83 | bool inside_dm_io; | |
84 | struct bio clone; | |
85 | }; | |
86 | ||
87 | /* | |
88 | * One of these is allocated per original bio. | |
89 | * It contains the first clone used for that original. | |
90 | */ | |
91 | #define DM_IO_MAGIC 5191977 | |
92 | struct dm_io { | |
93 | unsigned magic; | |
94 | struct mapped_device *md; | |
95 | blk_status_t status; | |
96 | atomic_t io_count; | |
97 | struct bio *orig_bio; | |
98 | unsigned long start_time; | |
99 | spinlock_t endio_lock; | |
100 | struct dm_stats_aux stats_aux; | |
101 | /* last member of dm_target_io is 'struct bio' */ | |
102 | struct dm_target_io tio; | |
103 | }; | |
104 | ||
105 | void *dm_per_bio_data(struct bio *bio, size_t data_size) | |
106 | { | |
107 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); | |
108 | if (!tio->inside_dm_io) | |
109 | return (char *)bio - offsetof(struct dm_target_io, clone) - data_size; | |
110 | return (char *)bio - offsetof(struct dm_target_io, clone) - offsetof(struct dm_io, tio) - data_size; | |
111 | } | |
112 | EXPORT_SYMBOL_GPL(dm_per_bio_data); | |
113 | ||
114 | struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size) | |
115 | { | |
116 | struct dm_io *io = (struct dm_io *)((char *)data + data_size); | |
117 | if (io->magic == DM_IO_MAGIC) | |
118 | return (struct bio *)((char *)io + offsetof(struct dm_io, tio) + offsetof(struct dm_target_io, clone)); | |
119 | BUG_ON(io->magic != DM_TIO_MAGIC); | |
120 | return (struct bio *)((char *)io + offsetof(struct dm_target_io, clone)); | |
121 | } | |
122 | EXPORT_SYMBOL_GPL(dm_bio_from_per_bio_data); | |
123 | ||
124 | unsigned dm_bio_get_target_bio_nr(const struct bio *bio) | |
125 | { | |
126 | return container_of(bio, struct dm_target_io, clone)->target_bio_nr; | |
127 | } | |
128 | EXPORT_SYMBOL_GPL(dm_bio_get_target_bio_nr); | |
129 | ||
130 | #define MINOR_ALLOCED ((void *)-1) | |
131 | ||
132 | /* | |
133 | * Bits for the md->flags field. | |
134 | */ | |
135 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 | |
136 | #define DMF_SUSPENDED 1 | |
137 | #define DMF_FROZEN 2 | |
138 | #define DMF_FREEING 3 | |
139 | #define DMF_DELETING 4 | |
140 | #define DMF_NOFLUSH_SUSPENDING 5 | |
141 | #define DMF_DEFERRED_REMOVE 6 | |
142 | #define DMF_SUSPENDED_INTERNALLY 7 | |
143 | ||
144 | #define DM_NUMA_NODE NUMA_NO_NODE | |
145 | static int dm_numa_node = DM_NUMA_NODE; | |
146 | ||
147 | /* | |
148 | * For mempools pre-allocation at the table loading time. | |
149 | */ | |
150 | struct dm_md_mempools { | |
151 | struct bio_set bs; | |
152 | struct bio_set io_bs; | |
153 | }; | |
154 | ||
155 | struct table_device { | |
156 | struct list_head list; | |
157 | refcount_t count; | |
158 | struct dm_dev dm_dev; | |
159 | }; | |
160 | ||
161 | /* | |
162 | * Bio-based DM's mempools' reserved IOs set by the user. | |
163 | */ | |
164 | #define RESERVED_BIO_BASED_IOS 16 | |
165 | static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; | |
166 | ||
167 | static int __dm_get_module_param_int(int *module_param, int min, int max) | |
168 | { | |
169 | int param = READ_ONCE(*module_param); | |
170 | int modified_param = 0; | |
171 | bool modified = true; | |
172 | ||
173 | if (param < min) | |
174 | modified_param = min; | |
175 | else if (param > max) | |
176 | modified_param = max; | |
177 | else | |
178 | modified = false; | |
179 | ||
180 | if (modified) { | |
181 | (void)cmpxchg(module_param, param, modified_param); | |
182 | param = modified_param; | |
183 | } | |
184 | ||
185 | return param; | |
186 | } | |
187 | ||
188 | unsigned __dm_get_module_param(unsigned *module_param, | |
189 | unsigned def, unsigned max) | |
190 | { | |
191 | unsigned param = READ_ONCE(*module_param); | |
192 | unsigned modified_param = 0; | |
193 | ||
194 | if (!param) | |
195 | modified_param = def; | |
196 | else if (param > max) | |
197 | modified_param = max; | |
198 | ||
199 | if (modified_param) { | |
200 | (void)cmpxchg(module_param, param, modified_param); | |
201 | param = modified_param; | |
202 | } | |
203 | ||
204 | return param; | |
205 | } | |
206 | ||
207 | unsigned dm_get_reserved_bio_based_ios(void) | |
208 | { | |
209 | return __dm_get_module_param(&reserved_bio_based_ios, | |
210 | RESERVED_BIO_BASED_IOS, DM_RESERVED_MAX_IOS); | |
211 | } | |
212 | EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); | |
213 | ||
214 | static unsigned dm_get_numa_node(void) | |
215 | { | |
216 | return __dm_get_module_param_int(&dm_numa_node, | |
217 | DM_NUMA_NODE, num_online_nodes() - 1); | |
218 | } | |
219 | ||
220 | static int __init local_init(void) | |
221 | { | |
222 | int r; | |
223 | ||
224 | r = dm_uevent_init(); | |
225 | if (r) | |
226 | return r; | |
227 | ||
228 | deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1); | |
229 | if (!deferred_remove_workqueue) { | |
230 | r = -ENOMEM; | |
231 | goto out_uevent_exit; | |
232 | } | |
233 | ||
234 | _major = major; | |
235 | r = register_blkdev(_major, _name); | |
236 | if (r < 0) | |
237 | goto out_free_workqueue; | |
238 | ||
239 | if (!_major) | |
240 | _major = r; | |
241 | ||
242 | return 0; | |
243 | ||
244 | out_free_workqueue: | |
245 | destroy_workqueue(deferred_remove_workqueue); | |
246 | out_uevent_exit: | |
247 | dm_uevent_exit(); | |
248 | ||
249 | return r; | |
250 | } | |
251 | ||
252 | static void local_exit(void) | |
253 | { | |
254 | flush_scheduled_work(); | |
255 | destroy_workqueue(deferred_remove_workqueue); | |
256 | ||
257 | unregister_blkdev(_major, _name); | |
258 | dm_uevent_exit(); | |
259 | ||
260 | _major = 0; | |
261 | ||
262 | DMINFO("cleaned up"); | |
263 | } | |
264 | ||
265 | static int (*_inits[])(void) __initdata = { | |
266 | local_init, | |
267 | dm_target_init, | |
268 | dm_linear_init, | |
269 | dm_stripe_init, | |
270 | dm_io_init, | |
271 | dm_kcopyd_init, | |
272 | dm_interface_init, | |
273 | dm_statistics_init, | |
274 | }; | |
275 | ||
276 | static void (*_exits[])(void) = { | |
277 | local_exit, | |
278 | dm_target_exit, | |
279 | dm_linear_exit, | |
280 | dm_stripe_exit, | |
281 | dm_io_exit, | |
282 | dm_kcopyd_exit, | |
283 | dm_interface_exit, | |
284 | dm_statistics_exit, | |
285 | }; | |
286 | ||
287 | static int __init dm_init(void) | |
288 | { | |
289 | const int count = ARRAY_SIZE(_inits); | |
290 | ||
291 | int r, i; | |
292 | ||
293 | for (i = 0; i < count; i++) { | |
294 | r = _inits[i](); | |
295 | if (r) | |
296 | goto bad; | |
297 | } | |
298 | ||
299 | return 0; | |
300 | ||
301 | bad: | |
302 | while (i--) | |
303 | _exits[i](); | |
304 | ||
305 | return r; | |
306 | } | |
307 | ||
308 | static void __exit dm_exit(void) | |
309 | { | |
310 | int i = ARRAY_SIZE(_exits); | |
311 | ||
312 | while (i--) | |
313 | _exits[i](); | |
314 | ||
315 | /* | |
316 | * Should be empty by this point. | |
317 | */ | |
318 | idr_destroy(&_minor_idr); | |
319 | } | |
320 | ||
321 | /* | |
322 | * Block device functions | |
323 | */ | |
324 | int dm_deleting_md(struct mapped_device *md) | |
325 | { | |
326 | return test_bit(DMF_DELETING, &md->flags); | |
327 | } | |
328 | ||
329 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) | |
330 | { | |
331 | struct mapped_device *md; | |
332 | ||
333 | spin_lock(&_minor_lock); | |
334 | ||
335 | md = bdev->bd_disk->private_data; | |
336 | if (!md) | |
337 | goto out; | |
338 | ||
339 | if (test_bit(DMF_FREEING, &md->flags) || | |
340 | dm_deleting_md(md)) { | |
341 | md = NULL; | |
342 | goto out; | |
343 | } | |
344 | ||
345 | dm_get(md); | |
346 | atomic_inc(&md->open_count); | |
347 | out: | |
348 | spin_unlock(&_minor_lock); | |
349 | ||
350 | return md ? 0 : -ENXIO; | |
351 | } | |
352 | ||
353 | static void dm_blk_close(struct gendisk *disk, fmode_t mode) | |
354 | { | |
355 | struct mapped_device *md; | |
356 | ||
357 | spin_lock(&_minor_lock); | |
358 | ||
359 | md = disk->private_data; | |
360 | if (WARN_ON(!md)) | |
361 | goto out; | |
362 | ||
363 | if (atomic_dec_and_test(&md->open_count) && | |
364 | (test_bit(DMF_DEFERRED_REMOVE, &md->flags))) | |
365 | queue_work(deferred_remove_workqueue, &deferred_remove_work); | |
366 | ||
367 | dm_put(md); | |
368 | out: | |
369 | spin_unlock(&_minor_lock); | |
370 | } | |
371 | ||
372 | int dm_open_count(struct mapped_device *md) | |
373 | { | |
374 | return atomic_read(&md->open_count); | |
375 | } | |
376 | ||
377 | /* | |
378 | * Guarantees nothing is using the device before it's deleted. | |
379 | */ | |
380 | int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred) | |
381 | { | |
382 | int r = 0; | |
383 | ||
384 | spin_lock(&_minor_lock); | |
385 | ||
386 | if (dm_open_count(md)) { | |
387 | r = -EBUSY; | |
388 | if (mark_deferred) | |
389 | set_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
390 | } else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags)) | |
391 | r = -EEXIST; | |
392 | else | |
393 | set_bit(DMF_DELETING, &md->flags); | |
394 | ||
395 | spin_unlock(&_minor_lock); | |
396 | ||
397 | return r; | |
398 | } | |
399 | ||
400 | int dm_cancel_deferred_remove(struct mapped_device *md) | |
401 | { | |
402 | int r = 0; | |
403 | ||
404 | spin_lock(&_minor_lock); | |
405 | ||
406 | if (test_bit(DMF_DELETING, &md->flags)) | |
407 | r = -EBUSY; | |
408 | else | |
409 | clear_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
410 | ||
411 | spin_unlock(&_minor_lock); | |
412 | ||
413 | return r; | |
414 | } | |
415 | ||
416 | static void do_deferred_remove(struct work_struct *w) | |
417 | { | |
418 | dm_deferred_remove(); | |
419 | } | |
420 | ||
421 | sector_t dm_get_size(struct mapped_device *md) | |
422 | { | |
423 | return get_capacity(md->disk); | |
424 | } | |
425 | ||
426 | struct request_queue *dm_get_md_queue(struct mapped_device *md) | |
427 | { | |
428 | return md->queue; | |
429 | } | |
430 | ||
431 | struct dm_stats *dm_get_stats(struct mapped_device *md) | |
432 | { | |
433 | return &md->stats; | |
434 | } | |
435 | ||
436 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) | |
437 | { | |
438 | struct mapped_device *md = bdev->bd_disk->private_data; | |
439 | ||
440 | return dm_get_geometry(md, geo); | |
441 | } | |
442 | ||
443 | static int dm_blk_report_zones(struct gendisk *disk, sector_t sector, | |
444 | struct blk_zone *zones, unsigned int *nr_zones) | |
445 | { | |
446 | #ifdef CONFIG_BLK_DEV_ZONED | |
447 | struct mapped_device *md = disk->private_data; | |
448 | struct dm_target *tgt; | |
449 | struct dm_table *map; | |
450 | int srcu_idx, ret; | |
451 | ||
452 | if (dm_suspended_md(md)) | |
453 | return -EAGAIN; | |
454 | ||
455 | map = dm_get_live_table(md, &srcu_idx); | |
456 | if (!map) | |
457 | return -EIO; | |
458 | ||
459 | tgt = dm_table_find_target(map, sector); | |
460 | if (!tgt) { | |
461 | ret = -EIO; | |
462 | goto out; | |
463 | } | |
464 | ||
465 | /* | |
466 | * If we are executing this, we already know that the block device | |
467 | * is a zoned device and so each target should have support for that | |
468 | * type of drive. A missing report_zones method means that the target | |
469 | * driver has a problem. | |
470 | */ | |
471 | if (WARN_ON(!tgt->type->report_zones)) { | |
472 | ret = -EIO; | |
473 | goto out; | |
474 | } | |
475 | ||
476 | /* | |
477 | * blkdev_report_zones() will loop and call this again to cover all the | |
478 | * zones of the target, eventually moving on to the next target. | |
479 | * So there is no need to loop here trying to fill the entire array | |
480 | * of zones. | |
481 | */ | |
482 | ret = tgt->type->report_zones(tgt, sector, zones, nr_zones); | |
483 | ||
484 | out: | |
485 | dm_put_live_table(md, srcu_idx); | |
486 | return ret; | |
487 | #else | |
488 | return -ENOTSUPP; | |
489 | #endif | |
490 | } | |
491 | ||
492 | static int dm_prepare_ioctl(struct mapped_device *md, int *srcu_idx, | |
493 | struct block_device **bdev) | |
494 | __acquires(md->io_barrier) | |
495 | { | |
496 | struct dm_target *tgt; | |
497 | struct dm_table *map; | |
498 | int r; | |
499 | ||
500 | retry: | |
501 | r = -ENOTTY; | |
502 | map = dm_get_live_table(md, srcu_idx); | |
503 | if (!map || !dm_table_get_size(map)) | |
504 | return r; | |
505 | ||
506 | /* We only support devices that have a single target */ | |
507 | if (dm_table_get_num_targets(map) != 1) | |
508 | return r; | |
509 | ||
510 | tgt = dm_table_get_target(map, 0); | |
511 | if (!tgt->type->prepare_ioctl) | |
512 | return r; | |
513 | ||
514 | if (dm_suspended_md(md)) | |
515 | return -EAGAIN; | |
516 | ||
517 | r = tgt->type->prepare_ioctl(tgt, bdev); | |
518 | if (r == -ENOTCONN && !fatal_signal_pending(current)) { | |
519 | dm_put_live_table(md, *srcu_idx); | |
520 | msleep(10); | |
521 | goto retry; | |
522 | } | |
523 | ||
524 | return r; | |
525 | } | |
526 | ||
527 | static void dm_unprepare_ioctl(struct mapped_device *md, int srcu_idx) | |
528 | __releases(md->io_barrier) | |
529 | { | |
530 | dm_put_live_table(md, srcu_idx); | |
531 | } | |
532 | ||
533 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, | |
534 | unsigned int cmd, unsigned long arg) | |
535 | { | |
536 | struct mapped_device *md = bdev->bd_disk->private_data; | |
537 | int r, srcu_idx; | |
538 | ||
539 | r = dm_prepare_ioctl(md, &srcu_idx, &bdev); | |
540 | if (r < 0) | |
541 | goto out; | |
542 | ||
543 | if (r > 0) { | |
544 | /* | |
545 | * Target determined this ioctl is being issued against a | |
546 | * subset of the parent bdev; require extra privileges. | |
547 | */ | |
548 | if (!capable(CAP_SYS_RAWIO)) { | |
549 | DMWARN_LIMIT( | |
550 | "%s: sending ioctl %x to DM device without required privilege.", | |
551 | current->comm, cmd); | |
552 | r = -ENOIOCTLCMD; | |
553 | goto out; | |
554 | } | |
555 | } | |
556 | ||
557 | r = __blkdev_driver_ioctl(bdev, mode, cmd, arg); | |
558 | out: | |
559 | dm_unprepare_ioctl(md, srcu_idx); | |
560 | return r; | |
561 | } | |
562 | ||
563 | static void start_io_acct(struct dm_io *io); | |
564 | ||
565 | static struct dm_io *alloc_io(struct mapped_device *md, struct bio *bio) | |
566 | { | |
567 | struct dm_io *io; | |
568 | struct dm_target_io *tio; | |
569 | struct bio *clone; | |
570 | ||
571 | clone = bio_alloc_bioset(GFP_NOIO, 0, &md->io_bs); | |
572 | if (!clone) | |
573 | return NULL; | |
574 | ||
575 | tio = container_of(clone, struct dm_target_io, clone); | |
576 | tio->inside_dm_io = true; | |
577 | tio->io = NULL; | |
578 | ||
579 | io = container_of(tio, struct dm_io, tio); | |
580 | io->magic = DM_IO_MAGIC; | |
581 | io->status = 0; | |
582 | atomic_set(&io->io_count, 1); | |
583 | io->orig_bio = bio; | |
584 | io->md = md; | |
585 | spin_lock_init(&io->endio_lock); | |
586 | ||
587 | start_io_acct(io); | |
588 | ||
589 | return io; | |
590 | } | |
591 | ||
592 | static void free_io(struct mapped_device *md, struct dm_io *io) | |
593 | { | |
594 | bio_put(&io->tio.clone); | |
595 | } | |
596 | ||
597 | static struct dm_target_io *alloc_tio(struct clone_info *ci, struct dm_target *ti, | |
598 | unsigned target_bio_nr, gfp_t gfp_mask) | |
599 | { | |
600 | struct dm_target_io *tio; | |
601 | ||
602 | if (!ci->io->tio.io) { | |
603 | /* the dm_target_io embedded in ci->io is available */ | |
604 | tio = &ci->io->tio; | |
605 | } else { | |
606 | struct bio *clone = bio_alloc_bioset(gfp_mask, 0, &ci->io->md->bs); | |
607 | if (!clone) | |
608 | return NULL; | |
609 | ||
610 | tio = container_of(clone, struct dm_target_io, clone); | |
611 | tio->inside_dm_io = false; | |
612 | } | |
613 | ||
614 | tio->magic = DM_TIO_MAGIC; | |
615 | tio->io = ci->io; | |
616 | tio->ti = ti; | |
617 | tio->target_bio_nr = target_bio_nr; | |
618 | ||
619 | return tio; | |
620 | } | |
621 | ||
622 | static void free_tio(struct dm_target_io *tio) | |
623 | { | |
624 | if (tio->inside_dm_io) | |
625 | return; | |
626 | bio_put(&tio->clone); | |
627 | } | |
628 | ||
629 | static bool md_in_flight_bios(struct mapped_device *md) | |
630 | { | |
631 | int cpu; | |
632 | struct hd_struct *part = &dm_disk(md)->part0; | |
633 | long sum = 0; | |
634 | ||
635 | for_each_possible_cpu(cpu) { | |
636 | sum += part_stat_local_read_cpu(part, in_flight[0], cpu); | |
637 | sum += part_stat_local_read_cpu(part, in_flight[1], cpu); | |
638 | } | |
639 | ||
640 | return sum != 0; | |
641 | } | |
642 | ||
643 | static bool md_in_flight(struct mapped_device *md) | |
644 | { | |
645 | if (queue_is_mq(md->queue)) | |
646 | return blk_mq_queue_inflight(md->queue); | |
647 | else | |
648 | return md_in_flight_bios(md); | |
649 | } | |
650 | ||
651 | static void start_io_acct(struct dm_io *io) | |
652 | { | |
653 | struct mapped_device *md = io->md; | |
654 | struct bio *bio = io->orig_bio; | |
655 | ||
656 | io->start_time = jiffies; | |
657 | ||
658 | generic_start_io_acct(md->queue, bio_op(bio), bio_sectors(bio), | |
659 | &dm_disk(md)->part0); | |
660 | ||
661 | if (unlikely(dm_stats_used(&md->stats))) | |
662 | dm_stats_account_io(&md->stats, bio_data_dir(bio), | |
663 | bio->bi_iter.bi_sector, bio_sectors(bio), | |
664 | false, 0, &io->stats_aux); | |
665 | } | |
666 | ||
667 | static void end_io_acct(struct dm_io *io) | |
668 | { | |
669 | struct mapped_device *md = io->md; | |
670 | struct bio *bio = io->orig_bio; | |
671 | unsigned long duration = jiffies - io->start_time; | |
672 | ||
673 | generic_end_io_acct(md->queue, bio_op(bio), &dm_disk(md)->part0, | |
674 | io->start_time); | |
675 | ||
676 | if (unlikely(dm_stats_used(&md->stats))) | |
677 | dm_stats_account_io(&md->stats, bio_data_dir(bio), | |
678 | bio->bi_iter.bi_sector, bio_sectors(bio), | |
679 | true, duration, &io->stats_aux); | |
680 | ||
681 | /* nudge anyone waiting on suspend queue */ | |
682 | if (unlikely(wq_has_sleeper(&md->wait))) | |
683 | wake_up(&md->wait); | |
684 | } | |
685 | ||
686 | /* | |
687 | * Add the bio to the list of deferred io. | |
688 | */ | |
689 | static void queue_io(struct mapped_device *md, struct bio *bio) | |
690 | { | |
691 | unsigned long flags; | |
692 | ||
693 | spin_lock_irqsave(&md->deferred_lock, flags); | |
694 | bio_list_add(&md->deferred, bio); | |
695 | spin_unlock_irqrestore(&md->deferred_lock, flags); | |
696 | queue_work(md->wq, &md->work); | |
697 | } | |
698 | ||
699 | /* | |
700 | * Everyone (including functions in this file), should use this | |
701 | * function to access the md->map field, and make sure they call | |
702 | * dm_put_live_table() when finished. | |
703 | */ | |
704 | struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier) | |
705 | { | |
706 | *srcu_idx = srcu_read_lock(&md->io_barrier); | |
707 | ||
708 | return srcu_dereference(md->map, &md->io_barrier); | |
709 | } | |
710 | ||
711 | void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier) | |
712 | { | |
713 | srcu_read_unlock(&md->io_barrier, srcu_idx); | |
714 | } | |
715 | ||
716 | void dm_sync_table(struct mapped_device *md) | |
717 | { | |
718 | synchronize_srcu(&md->io_barrier); | |
719 | synchronize_rcu_expedited(); | |
720 | } | |
721 | ||
722 | /* | |
723 | * A fast alternative to dm_get_live_table/dm_put_live_table. | |
724 | * The caller must not block between these two functions. | |
725 | */ | |
726 | static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU) | |
727 | { | |
728 | rcu_read_lock(); | |
729 | return rcu_dereference(md->map); | |
730 | } | |
731 | ||
732 | static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU) | |
733 | { | |
734 | rcu_read_unlock(); | |
735 | } | |
736 | ||
737 | static char *_dm_claim_ptr = "I belong to device-mapper"; | |
738 | ||
739 | /* | |
740 | * Open a table device so we can use it as a map destination. | |
741 | */ | |
742 | static int open_table_device(struct table_device *td, dev_t dev, | |
743 | struct mapped_device *md) | |
744 | { | |
745 | struct block_device *bdev; | |
746 | ||
747 | int r; | |
748 | ||
749 | BUG_ON(td->dm_dev.bdev); | |
750 | ||
751 | bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _dm_claim_ptr); | |
752 | if (IS_ERR(bdev)) | |
753 | return PTR_ERR(bdev); | |
754 | ||
755 | r = bd_link_disk_holder(bdev, dm_disk(md)); | |
756 | if (r) { | |
757 | blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL); | |
758 | return r; | |
759 | } | |
760 | ||
761 | td->dm_dev.bdev = bdev; | |
762 | td->dm_dev.dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); | |
763 | return 0; | |
764 | } | |
765 | ||
766 | /* | |
767 | * Close a table device that we've been using. | |
768 | */ | |
769 | static void close_table_device(struct table_device *td, struct mapped_device *md) | |
770 | { | |
771 | if (!td->dm_dev.bdev) | |
772 | return; | |
773 | ||
774 | bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md)); | |
775 | blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL); | |
776 | put_dax(td->dm_dev.dax_dev); | |
777 | td->dm_dev.bdev = NULL; | |
778 | td->dm_dev.dax_dev = NULL; | |
779 | } | |
780 | ||
781 | static struct table_device *find_table_device(struct list_head *l, dev_t dev, | |
782 | fmode_t mode) | |
783 | { | |
784 | struct table_device *td; | |
785 | ||
786 | list_for_each_entry(td, l, list) | |
787 | if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode) | |
788 | return td; | |
789 | ||
790 | return NULL; | |
791 | } | |
792 | ||
793 | int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, | |
794 | struct dm_dev **result) | |
795 | { | |
796 | int r; | |
797 | struct table_device *td; | |
798 | ||
799 | mutex_lock(&md->table_devices_lock); | |
800 | td = find_table_device(&md->table_devices, dev, mode); | |
801 | if (!td) { | |
802 | td = kmalloc_node(sizeof(*td), GFP_KERNEL, md->numa_node_id); | |
803 | if (!td) { | |
804 | mutex_unlock(&md->table_devices_lock); | |
805 | return -ENOMEM; | |
806 | } | |
807 | ||
808 | td->dm_dev.mode = mode; | |
809 | td->dm_dev.bdev = NULL; | |
810 | ||
811 | if ((r = open_table_device(td, dev, md))) { | |
812 | mutex_unlock(&md->table_devices_lock); | |
813 | kfree(td); | |
814 | return r; | |
815 | } | |
816 | ||
817 | format_dev_t(td->dm_dev.name, dev); | |
818 | ||
819 | refcount_set(&td->count, 1); | |
820 | list_add(&td->list, &md->table_devices); | |
821 | } else { | |
822 | refcount_inc(&td->count); | |
823 | } | |
824 | mutex_unlock(&md->table_devices_lock); | |
825 | ||
826 | *result = &td->dm_dev; | |
827 | return 0; | |
828 | } | |
829 | EXPORT_SYMBOL_GPL(dm_get_table_device); | |
830 | ||
831 | void dm_put_table_device(struct mapped_device *md, struct dm_dev *d) | |
832 | { | |
833 | struct table_device *td = container_of(d, struct table_device, dm_dev); | |
834 | ||
835 | mutex_lock(&md->table_devices_lock); | |
836 | if (refcount_dec_and_test(&td->count)) { | |
837 | close_table_device(td, md); | |
838 | list_del(&td->list); | |
839 | kfree(td); | |
840 | } | |
841 | mutex_unlock(&md->table_devices_lock); | |
842 | } | |
843 | EXPORT_SYMBOL(dm_put_table_device); | |
844 | ||
845 | static void free_table_devices(struct list_head *devices) | |
846 | { | |
847 | struct list_head *tmp, *next; | |
848 | ||
849 | list_for_each_safe(tmp, next, devices) { | |
850 | struct table_device *td = list_entry(tmp, struct table_device, list); | |
851 | ||
852 | DMWARN("dm_destroy: %s still exists with %d references", | |
853 | td->dm_dev.name, refcount_read(&td->count)); | |
854 | kfree(td); | |
855 | } | |
856 | } | |
857 | ||
858 | /* | |
859 | * Get the geometry associated with a dm device | |
860 | */ | |
861 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
862 | { | |
863 | *geo = md->geometry; | |
864 | ||
865 | return 0; | |
866 | } | |
867 | ||
868 | /* | |
869 | * Set the geometry of a device. | |
870 | */ | |
871 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) | |
872 | { | |
873 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; | |
874 | ||
875 | if (geo->start > sz) { | |
876 | DMWARN("Start sector is beyond the geometry limits."); | |
877 | return -EINVAL; | |
878 | } | |
879 | ||
880 | md->geometry = *geo; | |
881 | ||
882 | return 0; | |
883 | } | |
884 | ||
885 | static int __noflush_suspending(struct mapped_device *md) | |
886 | { | |
887 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
888 | } | |
889 | ||
890 | /* | |
891 | * Decrements the number of outstanding ios that a bio has been | |
892 | * cloned into, completing the original io if necc. | |
893 | */ | |
894 | static void dec_pending(struct dm_io *io, blk_status_t error) | |
895 | { | |
896 | unsigned long flags; | |
897 | blk_status_t io_error; | |
898 | struct bio *bio; | |
899 | struct mapped_device *md = io->md; | |
900 | ||
901 | /* Push-back supersedes any I/O errors */ | |
902 | if (unlikely(error)) { | |
903 | spin_lock_irqsave(&io->endio_lock, flags); | |
904 | if (!(io->status == BLK_STS_DM_REQUEUE && __noflush_suspending(md))) | |
905 | io->status = error; | |
906 | spin_unlock_irqrestore(&io->endio_lock, flags); | |
907 | } | |
908 | ||
909 | if (atomic_dec_and_test(&io->io_count)) { | |
910 | if (io->status == BLK_STS_DM_REQUEUE) { | |
911 | /* | |
912 | * Target requested pushing back the I/O. | |
913 | */ | |
914 | spin_lock_irqsave(&md->deferred_lock, flags); | |
915 | if (__noflush_suspending(md)) | |
916 | /* NOTE early return due to BLK_STS_DM_REQUEUE below */ | |
917 | bio_list_add_head(&md->deferred, io->orig_bio); | |
918 | else | |
919 | /* noflush suspend was interrupted. */ | |
920 | io->status = BLK_STS_IOERR; | |
921 | spin_unlock_irqrestore(&md->deferred_lock, flags); | |
922 | } | |
923 | ||
924 | io_error = io->status; | |
925 | bio = io->orig_bio; | |
926 | end_io_acct(io); | |
927 | free_io(md, io); | |
928 | ||
929 | if (io_error == BLK_STS_DM_REQUEUE) | |
930 | return; | |
931 | ||
932 | if ((bio->bi_opf & REQ_PREFLUSH) && bio->bi_iter.bi_size) { | |
933 | /* | |
934 | * Preflush done for flush with data, reissue | |
935 | * without REQ_PREFLUSH. | |
936 | */ | |
937 | bio->bi_opf &= ~REQ_PREFLUSH; | |
938 | queue_io(md, bio); | |
939 | } else { | |
940 | /* done with normal IO or empty flush */ | |
941 | if (io_error) | |
942 | bio->bi_status = io_error; | |
943 | bio_endio(bio); | |
944 | } | |
945 | } | |
946 | } | |
947 | ||
948 | void disable_discard(struct mapped_device *md) | |
949 | { | |
950 | struct queue_limits *limits = dm_get_queue_limits(md); | |
951 | ||
952 | /* device doesn't really support DISCARD, disable it */ | |
953 | limits->max_discard_sectors = 0; | |
954 | blk_queue_flag_clear(QUEUE_FLAG_DISCARD, md->queue); | |
955 | } | |
956 | ||
957 | void disable_write_same(struct mapped_device *md) | |
958 | { | |
959 | struct queue_limits *limits = dm_get_queue_limits(md); | |
960 | ||
961 | /* device doesn't really support WRITE SAME, disable it */ | |
962 | limits->max_write_same_sectors = 0; | |
963 | } | |
964 | ||
965 | void disable_write_zeroes(struct mapped_device *md) | |
966 | { | |
967 | struct queue_limits *limits = dm_get_queue_limits(md); | |
968 | ||
969 | /* device doesn't really support WRITE ZEROES, disable it */ | |
970 | limits->max_write_zeroes_sectors = 0; | |
971 | } | |
972 | ||
973 | static void clone_endio(struct bio *bio) | |
974 | { | |
975 | blk_status_t error = bio->bi_status; | |
976 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); | |
977 | struct dm_io *io = tio->io; | |
978 | struct mapped_device *md = tio->io->md; | |
979 | dm_endio_fn endio = tio->ti->type->end_io; | |
980 | ||
981 | if (unlikely(error == BLK_STS_TARGET) && md->type != DM_TYPE_NVME_BIO_BASED) { | |
982 | if (bio_op(bio) == REQ_OP_DISCARD && | |
983 | !bio->bi_disk->queue->limits.max_discard_sectors) | |
984 | disable_discard(md); | |
985 | else if (bio_op(bio) == REQ_OP_WRITE_SAME && | |
986 | !bio->bi_disk->queue->limits.max_write_same_sectors) | |
987 | disable_write_same(md); | |
988 | else if (bio_op(bio) == REQ_OP_WRITE_ZEROES && | |
989 | !bio->bi_disk->queue->limits.max_write_zeroes_sectors) | |
990 | disable_write_zeroes(md); | |
991 | } | |
992 | ||
993 | if (endio) { | |
994 | int r = endio(tio->ti, bio, &error); | |
995 | switch (r) { | |
996 | case DM_ENDIO_REQUEUE: | |
997 | error = BLK_STS_DM_REQUEUE; | |
998 | /*FALLTHRU*/ | |
999 | case DM_ENDIO_DONE: | |
1000 | break; | |
1001 | case DM_ENDIO_INCOMPLETE: | |
1002 | /* The target will handle the io */ | |
1003 | return; | |
1004 | default: | |
1005 | DMWARN("unimplemented target endio return value: %d", r); | |
1006 | BUG(); | |
1007 | } | |
1008 | } | |
1009 | ||
1010 | free_tio(tio); | |
1011 | dec_pending(io, error); | |
1012 | } | |
1013 | ||
1014 | /* | |
1015 | * Return maximum size of I/O possible at the supplied sector up to the current | |
1016 | * target boundary. | |
1017 | */ | |
1018 | static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti) | |
1019 | { | |
1020 | sector_t target_offset = dm_target_offset(ti, sector); | |
1021 | ||
1022 | return ti->len - target_offset; | |
1023 | } | |
1024 | ||
1025 | static sector_t max_io_len(sector_t sector, struct dm_target *ti) | |
1026 | { | |
1027 | sector_t len = max_io_len_target_boundary(sector, ti); | |
1028 | sector_t offset, max_len; | |
1029 | ||
1030 | /* | |
1031 | * Does the target need to split even further? | |
1032 | */ | |
1033 | if (ti->max_io_len) { | |
1034 | offset = dm_target_offset(ti, sector); | |
1035 | if (unlikely(ti->max_io_len & (ti->max_io_len - 1))) | |
1036 | max_len = sector_div(offset, ti->max_io_len); | |
1037 | else | |
1038 | max_len = offset & (ti->max_io_len - 1); | |
1039 | max_len = ti->max_io_len - max_len; | |
1040 | ||
1041 | if (len > max_len) | |
1042 | len = max_len; | |
1043 | } | |
1044 | ||
1045 | return len; | |
1046 | } | |
1047 | ||
1048 | int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) | |
1049 | { | |
1050 | if (len > UINT_MAX) { | |
1051 | DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)", | |
1052 | (unsigned long long)len, UINT_MAX); | |
1053 | ti->error = "Maximum size of target IO is too large"; | |
1054 | return -EINVAL; | |
1055 | } | |
1056 | ||
1057 | ti->max_io_len = (uint32_t) len; | |
1058 | ||
1059 | return 0; | |
1060 | } | |
1061 | EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); | |
1062 | ||
1063 | static struct dm_target *dm_dax_get_live_target(struct mapped_device *md, | |
1064 | sector_t sector, int *srcu_idx) | |
1065 | __acquires(md->io_barrier) | |
1066 | { | |
1067 | struct dm_table *map; | |
1068 | struct dm_target *ti; | |
1069 | ||
1070 | map = dm_get_live_table(md, srcu_idx); | |
1071 | if (!map) | |
1072 | return NULL; | |
1073 | ||
1074 | ti = dm_table_find_target(map, sector); | |
1075 | if (!ti) | |
1076 | return NULL; | |
1077 | ||
1078 | return ti; | |
1079 | } | |
1080 | ||
1081 | static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, | |
1082 | long nr_pages, void **kaddr, pfn_t *pfn) | |
1083 | { | |
1084 | struct mapped_device *md = dax_get_private(dax_dev); | |
1085 | sector_t sector = pgoff * PAGE_SECTORS; | |
1086 | struct dm_target *ti; | |
1087 | long len, ret = -EIO; | |
1088 | int srcu_idx; | |
1089 | ||
1090 | ti = dm_dax_get_live_target(md, sector, &srcu_idx); | |
1091 | ||
1092 | if (!ti) | |
1093 | goto out; | |
1094 | if (!ti->type->direct_access) | |
1095 | goto out; | |
1096 | len = max_io_len(sector, ti) / PAGE_SECTORS; | |
1097 | if (len < 1) | |
1098 | goto out; | |
1099 | nr_pages = min(len, nr_pages); | |
1100 | ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn); | |
1101 | ||
1102 | out: | |
1103 | dm_put_live_table(md, srcu_idx); | |
1104 | ||
1105 | return ret; | |
1106 | } | |
1107 | ||
1108 | static bool dm_dax_supported(struct dax_device *dax_dev, struct block_device *bdev, | |
1109 | int blocksize, sector_t start, sector_t len) | |
1110 | { | |
1111 | struct mapped_device *md = dax_get_private(dax_dev); | |
1112 | struct dm_table *map; | |
1113 | int srcu_idx; | |
1114 | bool ret; | |
1115 | ||
1116 | map = dm_get_live_table(md, &srcu_idx); | |
1117 | if (!map) | |
1118 | return false; | |
1119 | ||
1120 | ret = dm_table_supports_dax(map, device_supports_dax, &blocksize); | |
1121 | ||
1122 | dm_put_live_table(md, srcu_idx); | |
1123 | ||
1124 | return ret; | |
1125 | } | |
1126 | ||
1127 | static size_t dm_dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, | |
1128 | void *addr, size_t bytes, struct iov_iter *i) | |
1129 | { | |
1130 | struct mapped_device *md = dax_get_private(dax_dev); | |
1131 | sector_t sector = pgoff * PAGE_SECTORS; | |
1132 | struct dm_target *ti; | |
1133 | long ret = 0; | |
1134 | int srcu_idx; | |
1135 | ||
1136 | ti = dm_dax_get_live_target(md, sector, &srcu_idx); | |
1137 | ||
1138 | if (!ti) | |
1139 | goto out; | |
1140 | if (!ti->type->dax_copy_from_iter) { | |
1141 | ret = copy_from_iter(addr, bytes, i); | |
1142 | goto out; | |
1143 | } | |
1144 | ret = ti->type->dax_copy_from_iter(ti, pgoff, addr, bytes, i); | |
1145 | out: | |
1146 | dm_put_live_table(md, srcu_idx); | |
1147 | ||
1148 | return ret; | |
1149 | } | |
1150 | ||
1151 | static size_t dm_dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, | |
1152 | void *addr, size_t bytes, struct iov_iter *i) | |
1153 | { | |
1154 | struct mapped_device *md = dax_get_private(dax_dev); | |
1155 | sector_t sector = pgoff * PAGE_SECTORS; | |
1156 | struct dm_target *ti; | |
1157 | long ret = 0; | |
1158 | int srcu_idx; | |
1159 | ||
1160 | ti = dm_dax_get_live_target(md, sector, &srcu_idx); | |
1161 | ||
1162 | if (!ti) | |
1163 | goto out; | |
1164 | if (!ti->type->dax_copy_to_iter) { | |
1165 | ret = copy_to_iter(addr, bytes, i); | |
1166 | goto out; | |
1167 | } | |
1168 | ret = ti->type->dax_copy_to_iter(ti, pgoff, addr, bytes, i); | |
1169 | out: | |
1170 | dm_put_live_table(md, srcu_idx); | |
1171 | ||
1172 | return ret; | |
1173 | } | |
1174 | ||
1175 | /* | |
1176 | * A target may call dm_accept_partial_bio only from the map routine. It is | |
1177 | * allowed for all bio types except REQ_PREFLUSH and REQ_OP_ZONE_RESET. | |
1178 | * | |
1179 | * dm_accept_partial_bio informs the dm that the target only wants to process | |
1180 | * additional n_sectors sectors of the bio and the rest of the data should be | |
1181 | * sent in a next bio. | |
1182 | * | |
1183 | * A diagram that explains the arithmetics: | |
1184 | * +--------------------+---------------+-------+ | |
1185 | * | 1 | 2 | 3 | | |
1186 | * +--------------------+---------------+-------+ | |
1187 | * | |
1188 | * <-------------- *tio->len_ptr ---------------> | |
1189 | * <------- bi_size -------> | |
1190 | * <-- n_sectors --> | |
1191 | * | |
1192 | * Region 1 was already iterated over with bio_advance or similar function. | |
1193 | * (it may be empty if the target doesn't use bio_advance) | |
1194 | * Region 2 is the remaining bio size that the target wants to process. | |
1195 | * (it may be empty if region 1 is non-empty, although there is no reason | |
1196 | * to make it empty) | |
1197 | * The target requires that region 3 is to be sent in the next bio. | |
1198 | * | |
1199 | * If the target wants to receive multiple copies of the bio (via num_*bios, etc), | |
1200 | * the partially processed part (the sum of regions 1+2) must be the same for all | |
1201 | * copies of the bio. | |
1202 | */ | |
1203 | void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) | |
1204 | { | |
1205 | struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); | |
1206 | unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; | |
1207 | BUG_ON(bio->bi_opf & REQ_PREFLUSH); | |
1208 | BUG_ON(bi_size > *tio->len_ptr); | |
1209 | BUG_ON(n_sectors > bi_size); | |
1210 | *tio->len_ptr -= bi_size - n_sectors; | |
1211 | bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT; | |
1212 | } | |
1213 | EXPORT_SYMBOL_GPL(dm_accept_partial_bio); | |
1214 | ||
1215 | /* | |
1216 | * The zone descriptors obtained with a zone report indicate | |
1217 | * zone positions within the underlying device of the target. The zone | |
1218 | * descriptors must be remapped to match their position within the dm device. | |
1219 | * The caller target should obtain the zones information using | |
1220 | * blkdev_report_zones() to ensure that remapping for partition offset is | |
1221 | * already handled. | |
1222 | */ | |
1223 | void dm_remap_zone_report(struct dm_target *ti, sector_t start, | |
1224 | struct blk_zone *zones, unsigned int *nr_zones) | |
1225 | { | |
1226 | #ifdef CONFIG_BLK_DEV_ZONED | |
1227 | struct blk_zone *zone; | |
1228 | unsigned int nrz = *nr_zones; | |
1229 | int i; | |
1230 | ||
1231 | /* | |
1232 | * Remap the start sector and write pointer position of the zones in | |
1233 | * the array. Since we may have obtained from the target underlying | |
1234 | * device more zones that the target size, also adjust the number | |
1235 | * of zones. | |
1236 | */ | |
1237 | for (i = 0; i < nrz; i++) { | |
1238 | zone = zones + i; | |
1239 | if (zone->start >= start + ti->len) { | |
1240 | memset(zone, 0, sizeof(struct blk_zone) * (nrz - i)); | |
1241 | break; | |
1242 | } | |
1243 | ||
1244 | zone->start = zone->start + ti->begin - start; | |
1245 | if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) | |
1246 | continue; | |
1247 | ||
1248 | if (zone->cond == BLK_ZONE_COND_FULL) | |
1249 | zone->wp = zone->start + zone->len; | |
1250 | else if (zone->cond == BLK_ZONE_COND_EMPTY) | |
1251 | zone->wp = zone->start; | |
1252 | else | |
1253 | zone->wp = zone->wp + ti->begin - start; | |
1254 | } | |
1255 | ||
1256 | *nr_zones = i; | |
1257 | #else /* !CONFIG_BLK_DEV_ZONED */ | |
1258 | *nr_zones = 0; | |
1259 | #endif | |
1260 | } | |
1261 | EXPORT_SYMBOL_GPL(dm_remap_zone_report); | |
1262 | ||
1263 | static blk_qc_t __map_bio(struct dm_target_io *tio) | |
1264 | { | |
1265 | int r; | |
1266 | sector_t sector; | |
1267 | struct bio *clone = &tio->clone; | |
1268 | struct dm_io *io = tio->io; | |
1269 | struct mapped_device *md = io->md; | |
1270 | struct dm_target *ti = tio->ti; | |
1271 | blk_qc_t ret = BLK_QC_T_NONE; | |
1272 | ||
1273 | clone->bi_end_io = clone_endio; | |
1274 | ||
1275 | /* | |
1276 | * Map the clone. If r == 0 we don't need to do | |
1277 | * anything, the target has assumed ownership of | |
1278 | * this io. | |
1279 | */ | |
1280 | atomic_inc(&io->io_count); | |
1281 | sector = clone->bi_iter.bi_sector; | |
1282 | ||
1283 | r = ti->type->map(ti, clone); | |
1284 | switch (r) { | |
1285 | case DM_MAPIO_SUBMITTED: | |
1286 | break; | |
1287 | case DM_MAPIO_REMAPPED: | |
1288 | /* the bio has been remapped so dispatch it */ | |
1289 | trace_block_bio_remap(clone->bi_disk->queue, clone, | |
1290 | bio_dev(io->orig_bio), sector); | |
1291 | if (md->type == DM_TYPE_NVME_BIO_BASED) | |
1292 | ret = direct_make_request(clone); | |
1293 | else | |
1294 | ret = generic_make_request(clone); | |
1295 | break; | |
1296 | case DM_MAPIO_KILL: | |
1297 | free_tio(tio); | |
1298 | dec_pending(io, BLK_STS_IOERR); | |
1299 | break; | |
1300 | case DM_MAPIO_REQUEUE: | |
1301 | free_tio(tio); | |
1302 | dec_pending(io, BLK_STS_DM_REQUEUE); | |
1303 | break; | |
1304 | default: | |
1305 | DMWARN("unimplemented target map return value: %d", r); | |
1306 | BUG(); | |
1307 | } | |
1308 | ||
1309 | return ret; | |
1310 | } | |
1311 | ||
1312 | static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) | |
1313 | { | |
1314 | bio->bi_iter.bi_sector = sector; | |
1315 | bio->bi_iter.bi_size = to_bytes(len); | |
1316 | } | |
1317 | ||
1318 | /* | |
1319 | * Creates a bio that consists of range of complete bvecs. | |
1320 | */ | |
1321 | static int clone_bio(struct dm_target_io *tio, struct bio *bio, | |
1322 | sector_t sector, unsigned len) | |
1323 | { | |
1324 | struct bio *clone = &tio->clone; | |
1325 | ||
1326 | __bio_clone_fast(clone, bio); | |
1327 | ||
1328 | if (bio_integrity(bio)) { | |
1329 | int r; | |
1330 | ||
1331 | if (unlikely(!dm_target_has_integrity(tio->ti->type) && | |
1332 | !dm_target_passes_integrity(tio->ti->type))) { | |
1333 | DMWARN("%s: the target %s doesn't support integrity data.", | |
1334 | dm_device_name(tio->io->md), | |
1335 | tio->ti->type->name); | |
1336 | return -EIO; | |
1337 | } | |
1338 | ||
1339 | r = bio_integrity_clone(clone, bio, GFP_NOIO); | |
1340 | if (r < 0) | |
1341 | return r; | |
1342 | } | |
1343 | ||
1344 | bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); | |
1345 | clone->bi_iter.bi_size = to_bytes(len); | |
1346 | ||
1347 | if (bio_integrity(bio)) | |
1348 | bio_integrity_trim(clone); | |
1349 | ||
1350 | return 0; | |
1351 | } | |
1352 | ||
1353 | static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, | |
1354 | struct dm_target *ti, unsigned num_bios) | |
1355 | { | |
1356 | struct dm_target_io *tio; | |
1357 | int try; | |
1358 | ||
1359 | if (!num_bios) | |
1360 | return; | |
1361 | ||
1362 | if (num_bios == 1) { | |
1363 | tio = alloc_tio(ci, ti, 0, GFP_NOIO); | |
1364 | bio_list_add(blist, &tio->clone); | |
1365 | return; | |
1366 | } | |
1367 | ||
1368 | for (try = 0; try < 2; try++) { | |
1369 | int bio_nr; | |
1370 | struct bio *bio; | |
1371 | ||
1372 | if (try) | |
1373 | mutex_lock(&ci->io->md->table_devices_lock); | |
1374 | for (bio_nr = 0; bio_nr < num_bios; bio_nr++) { | |
1375 | tio = alloc_tio(ci, ti, bio_nr, try ? GFP_NOIO : GFP_NOWAIT); | |
1376 | if (!tio) | |
1377 | break; | |
1378 | ||
1379 | bio_list_add(blist, &tio->clone); | |
1380 | } | |
1381 | if (try) | |
1382 | mutex_unlock(&ci->io->md->table_devices_lock); | |
1383 | if (bio_nr == num_bios) | |
1384 | return; | |
1385 | ||
1386 | while ((bio = bio_list_pop(blist))) { | |
1387 | tio = container_of(bio, struct dm_target_io, clone); | |
1388 | free_tio(tio); | |
1389 | } | |
1390 | } | |
1391 | } | |
1392 | ||
1393 | static blk_qc_t __clone_and_map_simple_bio(struct clone_info *ci, | |
1394 | struct dm_target_io *tio, unsigned *len) | |
1395 | { | |
1396 | struct bio *clone = &tio->clone; | |
1397 | ||
1398 | tio->len_ptr = len; | |
1399 | ||
1400 | __bio_clone_fast(clone, ci->bio); | |
1401 | if (len) | |
1402 | bio_setup_sector(clone, ci->sector, *len); | |
1403 | ||
1404 | return __map_bio(tio); | |
1405 | } | |
1406 | ||
1407 | static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, | |
1408 | unsigned num_bios, unsigned *len) | |
1409 | { | |
1410 | struct bio_list blist = BIO_EMPTY_LIST; | |
1411 | struct bio *bio; | |
1412 | struct dm_target_io *tio; | |
1413 | ||
1414 | alloc_multiple_bios(&blist, ci, ti, num_bios); | |
1415 | ||
1416 | while ((bio = bio_list_pop(&blist))) { | |
1417 | tio = container_of(bio, struct dm_target_io, clone); | |
1418 | (void) __clone_and_map_simple_bio(ci, tio, len); | |
1419 | } | |
1420 | } | |
1421 | ||
1422 | static int __send_empty_flush(struct clone_info *ci) | |
1423 | { | |
1424 | unsigned target_nr = 0; | |
1425 | struct dm_target *ti; | |
1426 | ||
1427 | /* | |
1428 | * Empty flush uses a statically initialized bio, as the base for | |
1429 | * cloning. However, blkg association requires that a bdev is | |
1430 | * associated with a gendisk, which doesn't happen until the bdev is | |
1431 | * opened. So, blkg association is done at issue time of the flush | |
1432 | * rather than when the device is created in alloc_dev(). | |
1433 | */ | |
1434 | bio_set_dev(ci->bio, ci->io->md->bdev); | |
1435 | ||
1436 | BUG_ON(bio_has_data(ci->bio)); | |
1437 | while ((ti = dm_table_get_target(ci->map, target_nr++))) | |
1438 | __send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL); | |
1439 | ||
1440 | bio_disassociate_blkg(ci->bio); | |
1441 | ||
1442 | return 0; | |
1443 | } | |
1444 | ||
1445 | static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, | |
1446 | sector_t sector, unsigned *len) | |
1447 | { | |
1448 | struct bio *bio = ci->bio; | |
1449 | struct dm_target_io *tio; | |
1450 | int r; | |
1451 | ||
1452 | tio = alloc_tio(ci, ti, 0, GFP_NOIO); | |
1453 | tio->len_ptr = len; | |
1454 | r = clone_bio(tio, bio, sector, *len); | |
1455 | if (r < 0) { | |
1456 | free_tio(tio); | |
1457 | return r; | |
1458 | } | |
1459 | (void) __map_bio(tio); | |
1460 | ||
1461 | return 0; | |
1462 | } | |
1463 | ||
1464 | typedef unsigned (*get_num_bios_fn)(struct dm_target *ti); | |
1465 | ||
1466 | static unsigned get_num_discard_bios(struct dm_target *ti) | |
1467 | { | |
1468 | return ti->num_discard_bios; | |
1469 | } | |
1470 | ||
1471 | static unsigned get_num_secure_erase_bios(struct dm_target *ti) | |
1472 | { | |
1473 | return ti->num_secure_erase_bios; | |
1474 | } | |
1475 | ||
1476 | static unsigned get_num_write_same_bios(struct dm_target *ti) | |
1477 | { | |
1478 | return ti->num_write_same_bios; | |
1479 | } | |
1480 | ||
1481 | static unsigned get_num_write_zeroes_bios(struct dm_target *ti) | |
1482 | { | |
1483 | return ti->num_write_zeroes_bios; | |
1484 | } | |
1485 | ||
1486 | static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *ti, | |
1487 | unsigned num_bios) | |
1488 | { | |
1489 | unsigned len; | |
1490 | ||
1491 | /* | |
1492 | * Even though the device advertised support for this type of | |
1493 | * request, that does not mean every target supports it, and | |
1494 | * reconfiguration might also have changed that since the | |
1495 | * check was performed. | |
1496 | */ | |
1497 | if (!num_bios) | |
1498 | return -EOPNOTSUPP; | |
1499 | ||
1500 | len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); | |
1501 | ||
1502 | __send_duplicate_bios(ci, ti, num_bios, &len); | |
1503 | ||
1504 | ci->sector += len; | |
1505 | ci->sector_count -= len; | |
1506 | ||
1507 | return 0; | |
1508 | } | |
1509 | ||
1510 | static int __send_discard(struct clone_info *ci, struct dm_target *ti) | |
1511 | { | |
1512 | return __send_changing_extent_only(ci, ti, get_num_discard_bios(ti)); | |
1513 | } | |
1514 | ||
1515 | static int __send_secure_erase(struct clone_info *ci, struct dm_target *ti) | |
1516 | { | |
1517 | return __send_changing_extent_only(ci, ti, get_num_secure_erase_bios(ti)); | |
1518 | } | |
1519 | ||
1520 | static int __send_write_same(struct clone_info *ci, struct dm_target *ti) | |
1521 | { | |
1522 | return __send_changing_extent_only(ci, ti, get_num_write_same_bios(ti)); | |
1523 | } | |
1524 | ||
1525 | static int __send_write_zeroes(struct clone_info *ci, struct dm_target *ti) | |
1526 | { | |
1527 | return __send_changing_extent_only(ci, ti, get_num_write_zeroes_bios(ti)); | |
1528 | } | |
1529 | ||
1530 | static bool is_abnormal_io(struct bio *bio) | |
1531 | { | |
1532 | bool r = false; | |
1533 | ||
1534 | switch (bio_op(bio)) { | |
1535 | case REQ_OP_DISCARD: | |
1536 | case REQ_OP_SECURE_ERASE: | |
1537 | case REQ_OP_WRITE_SAME: | |
1538 | case REQ_OP_WRITE_ZEROES: | |
1539 | r = true; | |
1540 | break; | |
1541 | } | |
1542 | ||
1543 | return r; | |
1544 | } | |
1545 | ||
1546 | static bool __process_abnormal_io(struct clone_info *ci, struct dm_target *ti, | |
1547 | int *result) | |
1548 | { | |
1549 | struct bio *bio = ci->bio; | |
1550 | ||
1551 | if (bio_op(bio) == REQ_OP_DISCARD) | |
1552 | *result = __send_discard(ci, ti); | |
1553 | else if (bio_op(bio) == REQ_OP_SECURE_ERASE) | |
1554 | *result = __send_secure_erase(ci, ti); | |
1555 | else if (bio_op(bio) == REQ_OP_WRITE_SAME) | |
1556 | *result = __send_write_same(ci, ti); | |
1557 | else if (bio_op(bio) == REQ_OP_WRITE_ZEROES) | |
1558 | *result = __send_write_zeroes(ci, ti); | |
1559 | else | |
1560 | return false; | |
1561 | ||
1562 | return true; | |
1563 | } | |
1564 | ||
1565 | /* | |
1566 | * Select the correct strategy for processing a non-flush bio. | |
1567 | */ | |
1568 | static int __split_and_process_non_flush(struct clone_info *ci) | |
1569 | { | |
1570 | struct dm_target *ti; | |
1571 | unsigned len; | |
1572 | int r; | |
1573 | ||
1574 | ti = dm_table_find_target(ci->map, ci->sector); | |
1575 | if (!ti) | |
1576 | return -EIO; | |
1577 | ||
1578 | if (__process_abnormal_io(ci, ti, &r)) | |
1579 | return r; | |
1580 | ||
1581 | len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count); | |
1582 | ||
1583 | r = __clone_and_map_data_bio(ci, ti, ci->sector, &len); | |
1584 | if (r < 0) | |
1585 | return r; | |
1586 | ||
1587 | ci->sector += len; | |
1588 | ci->sector_count -= len; | |
1589 | ||
1590 | return 0; | |
1591 | } | |
1592 | ||
1593 | static void init_clone_info(struct clone_info *ci, struct mapped_device *md, | |
1594 | struct dm_table *map, struct bio *bio) | |
1595 | { | |
1596 | ci->map = map; | |
1597 | ci->io = alloc_io(md, bio); | |
1598 | ci->sector = bio->bi_iter.bi_sector; | |
1599 | } | |
1600 | ||
1601 | #define __dm_part_stat_sub(part, field, subnd) \ | |
1602 | (part_stat_get(part, field) -= (subnd)) | |
1603 | ||
1604 | /* | |
1605 | * Entry point to split a bio into clones and submit them to the targets. | |
1606 | */ | |
1607 | static blk_qc_t __split_and_process_bio(struct mapped_device *md, | |
1608 | struct dm_table *map, struct bio *bio) | |
1609 | { | |
1610 | struct clone_info ci; | |
1611 | blk_qc_t ret = BLK_QC_T_NONE; | |
1612 | int error = 0; | |
1613 | ||
1614 | init_clone_info(&ci, md, map, bio); | |
1615 | ||
1616 | if (bio->bi_opf & REQ_PREFLUSH) { | |
1617 | struct bio flush_bio; | |
1618 | ||
1619 | /* | |
1620 | * Use an on-stack bio for this, it's safe since we don't | |
1621 | * need to reference it after submit. It's just used as | |
1622 | * the basis for the clone(s). | |
1623 | */ | |
1624 | bio_init(&flush_bio, NULL, 0); | |
1625 | flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; | |
1626 | ci.bio = &flush_bio; | |
1627 | ci.sector_count = 0; | |
1628 | error = __send_empty_flush(&ci); | |
1629 | /* dec_pending submits any data associated with flush */ | |
1630 | } else if (bio_op(bio) == REQ_OP_ZONE_RESET) { | |
1631 | ci.bio = bio; | |
1632 | ci.sector_count = 0; | |
1633 | error = __split_and_process_non_flush(&ci); | |
1634 | } else { | |
1635 | ci.bio = bio; | |
1636 | ci.sector_count = bio_sectors(bio); | |
1637 | while (ci.sector_count && !error) { | |
1638 | error = __split_and_process_non_flush(&ci); | |
1639 | if (current->bio_list && ci.sector_count && !error) { | |
1640 | /* | |
1641 | * Remainder must be passed to generic_make_request() | |
1642 | * so that it gets handled *after* bios already submitted | |
1643 | * have been completely processed. | |
1644 | * We take a clone of the original to store in | |
1645 | * ci.io->orig_bio to be used by end_io_acct() and | |
1646 | * for dec_pending to use for completion handling. | |
1647 | */ | |
1648 | struct bio *b = bio_split(bio, bio_sectors(bio) - ci.sector_count, | |
1649 | GFP_NOIO, &md->queue->bio_split); | |
1650 | ci.io->orig_bio = b; | |
1651 | ||
1652 | /* | |
1653 | * Adjust IO stats for each split, otherwise upon queue | |
1654 | * reentry there will be redundant IO accounting. | |
1655 | * NOTE: this is a stop-gap fix, a proper fix involves | |
1656 | * significant refactoring of DM core's bio splitting | |
1657 | * (by eliminating DM's splitting and just using bio_split) | |
1658 | */ | |
1659 | part_stat_lock(); | |
1660 | __dm_part_stat_sub(&dm_disk(md)->part0, | |
1661 | sectors[op_stat_group(bio_op(bio))], ci.sector_count); | |
1662 | part_stat_unlock(); | |
1663 | ||
1664 | bio_chain(b, bio); | |
1665 | trace_block_split(md->queue, b, bio->bi_iter.bi_sector); | |
1666 | ret = generic_make_request(bio); | |
1667 | break; | |
1668 | } | |
1669 | } | |
1670 | } | |
1671 | ||
1672 | /* drop the extra reference count */ | |
1673 | dec_pending(ci.io, errno_to_blk_status(error)); | |
1674 | return ret; | |
1675 | } | |
1676 | ||
1677 | /* | |
1678 | * Optimized variant of __split_and_process_bio that leverages the | |
1679 | * fact that targets that use it do _not_ have a need to split bios. | |
1680 | */ | |
1681 | static blk_qc_t __process_bio(struct mapped_device *md, struct dm_table *map, | |
1682 | struct bio *bio, struct dm_target *ti) | |
1683 | { | |
1684 | struct clone_info ci; | |
1685 | blk_qc_t ret = BLK_QC_T_NONE; | |
1686 | int error = 0; | |
1687 | ||
1688 | init_clone_info(&ci, md, map, bio); | |
1689 | ||
1690 | if (bio->bi_opf & REQ_PREFLUSH) { | |
1691 | struct bio flush_bio; | |
1692 | ||
1693 | /* | |
1694 | * Use an on-stack bio for this, it's safe since we don't | |
1695 | * need to reference it after submit. It's just used as | |
1696 | * the basis for the clone(s). | |
1697 | */ | |
1698 | bio_init(&flush_bio, NULL, 0); | |
1699 | flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; | |
1700 | ci.bio = &flush_bio; | |
1701 | ci.sector_count = 0; | |
1702 | error = __send_empty_flush(&ci); | |
1703 | /* dec_pending submits any data associated with flush */ | |
1704 | } else { | |
1705 | struct dm_target_io *tio; | |
1706 | ||
1707 | ci.bio = bio; | |
1708 | ci.sector_count = bio_sectors(bio); | |
1709 | if (__process_abnormal_io(&ci, ti, &error)) | |
1710 | goto out; | |
1711 | ||
1712 | tio = alloc_tio(&ci, ti, 0, GFP_NOIO); | |
1713 | ret = __clone_and_map_simple_bio(&ci, tio, NULL); | |
1714 | } | |
1715 | out: | |
1716 | /* drop the extra reference count */ | |
1717 | dec_pending(ci.io, errno_to_blk_status(error)); | |
1718 | return ret; | |
1719 | } | |
1720 | ||
1721 | static void dm_queue_split(struct mapped_device *md, struct dm_target *ti, struct bio **bio) | |
1722 | { | |
1723 | unsigned len, sector_count; | |
1724 | ||
1725 | sector_count = bio_sectors(*bio); | |
1726 | len = min_t(sector_t, max_io_len((*bio)->bi_iter.bi_sector, ti), sector_count); | |
1727 | ||
1728 | if (sector_count > len) { | |
1729 | struct bio *split = bio_split(*bio, len, GFP_NOIO, &md->queue->bio_split); | |
1730 | ||
1731 | bio_chain(split, *bio); | |
1732 | trace_block_split(md->queue, split, (*bio)->bi_iter.bi_sector); | |
1733 | generic_make_request(*bio); | |
1734 | *bio = split; | |
1735 | } | |
1736 | } | |
1737 | ||
1738 | static blk_qc_t dm_process_bio(struct mapped_device *md, | |
1739 | struct dm_table *map, struct bio *bio) | |
1740 | { | |
1741 | blk_qc_t ret = BLK_QC_T_NONE; | |
1742 | struct dm_target *ti = md->immutable_target; | |
1743 | ||
1744 | if (unlikely(!map)) { | |
1745 | bio_io_error(bio); | |
1746 | return ret; | |
1747 | } | |
1748 | ||
1749 | if (!ti) { | |
1750 | ti = dm_table_find_target(map, bio->bi_iter.bi_sector); | |
1751 | if (unlikely(!ti)) { | |
1752 | bio_io_error(bio); | |
1753 | return ret; | |
1754 | } | |
1755 | } | |
1756 | ||
1757 | /* | |
1758 | * If in ->make_request_fn we need to use blk_queue_split(), otherwise | |
1759 | * queue_limits for abnormal requests (e.g. discard, writesame, etc) | |
1760 | * won't be imposed. | |
1761 | */ | |
1762 | if (current->bio_list) { | |
1763 | blk_queue_split(md->queue, &bio); | |
1764 | if (!is_abnormal_io(bio)) | |
1765 | dm_queue_split(md, ti, &bio); | |
1766 | } | |
1767 | ||
1768 | if (dm_get_md_type(md) == DM_TYPE_NVME_BIO_BASED) | |
1769 | return __process_bio(md, map, bio, ti); | |
1770 | else | |
1771 | return __split_and_process_bio(md, map, bio); | |
1772 | } | |
1773 | ||
1774 | static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio) | |
1775 | { | |
1776 | struct mapped_device *md = q->queuedata; | |
1777 | blk_qc_t ret = BLK_QC_T_NONE; | |
1778 | int srcu_idx; | |
1779 | struct dm_table *map; | |
1780 | ||
1781 | map = dm_get_live_table(md, &srcu_idx); | |
1782 | ||
1783 | /* if we're suspended, we have to queue this io for later */ | |
1784 | if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { | |
1785 | dm_put_live_table(md, srcu_idx); | |
1786 | ||
1787 | if (!(bio->bi_opf & REQ_RAHEAD)) | |
1788 | queue_io(md, bio); | |
1789 | else | |
1790 | bio_io_error(bio); | |
1791 | return ret; | |
1792 | } | |
1793 | ||
1794 | ret = dm_process_bio(md, map, bio); | |
1795 | ||
1796 | dm_put_live_table(md, srcu_idx); | |
1797 | return ret; | |
1798 | } | |
1799 | ||
1800 | static int dm_any_congested(void *congested_data, int bdi_bits) | |
1801 | { | |
1802 | int r = bdi_bits; | |
1803 | struct mapped_device *md = congested_data; | |
1804 | struct dm_table *map; | |
1805 | ||
1806 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { | |
1807 | if (dm_request_based(md)) { | |
1808 | /* | |
1809 | * With request-based DM we only need to check the | |
1810 | * top-level queue for congestion. | |
1811 | */ | |
1812 | r = md->queue->backing_dev_info->wb.state & bdi_bits; | |
1813 | } else { | |
1814 | map = dm_get_live_table_fast(md); | |
1815 | if (map) | |
1816 | r = dm_table_any_congested(map, bdi_bits); | |
1817 | dm_put_live_table_fast(md); | |
1818 | } | |
1819 | } | |
1820 | ||
1821 | return r; | |
1822 | } | |
1823 | ||
1824 | /*----------------------------------------------------------------- | |
1825 | * An IDR is used to keep track of allocated minor numbers. | |
1826 | *---------------------------------------------------------------*/ | |
1827 | static void free_minor(int minor) | |
1828 | { | |
1829 | spin_lock(&_minor_lock); | |
1830 | idr_remove(&_minor_idr, minor); | |
1831 | spin_unlock(&_minor_lock); | |
1832 | } | |
1833 | ||
1834 | /* | |
1835 | * See if the device with a specific minor # is free. | |
1836 | */ | |
1837 | static int specific_minor(int minor) | |
1838 | { | |
1839 | int r; | |
1840 | ||
1841 | if (minor >= (1 << MINORBITS)) | |
1842 | return -EINVAL; | |
1843 | ||
1844 | idr_preload(GFP_KERNEL); | |
1845 | spin_lock(&_minor_lock); | |
1846 | ||
1847 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT); | |
1848 | ||
1849 | spin_unlock(&_minor_lock); | |
1850 | idr_preload_end(); | |
1851 | if (r < 0) | |
1852 | return r == -ENOSPC ? -EBUSY : r; | |
1853 | return 0; | |
1854 | } | |
1855 | ||
1856 | static int next_free_minor(int *minor) | |
1857 | { | |
1858 | int r; | |
1859 | ||
1860 | idr_preload(GFP_KERNEL); | |
1861 | spin_lock(&_minor_lock); | |
1862 | ||
1863 | r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT); | |
1864 | ||
1865 | spin_unlock(&_minor_lock); | |
1866 | idr_preload_end(); | |
1867 | if (r < 0) | |
1868 | return r; | |
1869 | *minor = r; | |
1870 | return 0; | |
1871 | } | |
1872 | ||
1873 | static const struct block_device_operations dm_blk_dops; | |
1874 | static const struct dax_operations dm_dax_ops; | |
1875 | ||
1876 | static void dm_wq_work(struct work_struct *work); | |
1877 | ||
1878 | static void dm_init_normal_md_queue(struct mapped_device *md) | |
1879 | { | |
1880 | /* | |
1881 | * Initialize aspects of queue that aren't relevant for blk-mq | |
1882 | */ | |
1883 | md->queue->backing_dev_info->congested_fn = dm_any_congested; | |
1884 | } | |
1885 | ||
1886 | static void cleanup_mapped_device(struct mapped_device *md) | |
1887 | { | |
1888 | if (md->wq) | |
1889 | destroy_workqueue(md->wq); | |
1890 | bioset_exit(&md->bs); | |
1891 | bioset_exit(&md->io_bs); | |
1892 | ||
1893 | if (md->dax_dev) { | |
1894 | kill_dax(md->dax_dev); | |
1895 | put_dax(md->dax_dev); | |
1896 | md->dax_dev = NULL; | |
1897 | } | |
1898 | ||
1899 | if (md->disk) { | |
1900 | spin_lock(&_minor_lock); | |
1901 | md->disk->private_data = NULL; | |
1902 | spin_unlock(&_minor_lock); | |
1903 | del_gendisk(md->disk); | |
1904 | put_disk(md->disk); | |
1905 | } | |
1906 | ||
1907 | if (md->queue) | |
1908 | blk_cleanup_queue(md->queue); | |
1909 | ||
1910 | cleanup_srcu_struct(&md->io_barrier); | |
1911 | ||
1912 | if (md->bdev) { | |
1913 | bdput(md->bdev); | |
1914 | md->bdev = NULL; | |
1915 | } | |
1916 | ||
1917 | mutex_destroy(&md->suspend_lock); | |
1918 | mutex_destroy(&md->type_lock); | |
1919 | mutex_destroy(&md->table_devices_lock); | |
1920 | ||
1921 | dm_mq_cleanup_mapped_device(md); | |
1922 | } | |
1923 | ||
1924 | /* | |
1925 | * Allocate and initialise a blank device with a given minor. | |
1926 | */ | |
1927 | static struct mapped_device *alloc_dev(int minor) | |
1928 | { | |
1929 | int r, numa_node_id = dm_get_numa_node(); | |
1930 | struct mapped_device *md; | |
1931 | void *old_md; | |
1932 | ||
1933 | md = kvzalloc_node(sizeof(*md), GFP_KERNEL, numa_node_id); | |
1934 | if (!md) { | |
1935 | DMWARN("unable to allocate device, out of memory."); | |
1936 | return NULL; | |
1937 | } | |
1938 | ||
1939 | if (!try_module_get(THIS_MODULE)) | |
1940 | goto bad_module_get; | |
1941 | ||
1942 | /* get a minor number for the dev */ | |
1943 | if (minor == DM_ANY_MINOR) | |
1944 | r = next_free_minor(&minor); | |
1945 | else | |
1946 | r = specific_minor(minor); | |
1947 | if (r < 0) | |
1948 | goto bad_minor; | |
1949 | ||
1950 | r = init_srcu_struct(&md->io_barrier); | |
1951 | if (r < 0) | |
1952 | goto bad_io_barrier; | |
1953 | ||
1954 | md->numa_node_id = numa_node_id; | |
1955 | md->init_tio_pdu = false; | |
1956 | md->type = DM_TYPE_NONE; | |
1957 | mutex_init(&md->suspend_lock); | |
1958 | mutex_init(&md->type_lock); | |
1959 | mutex_init(&md->table_devices_lock); | |
1960 | spin_lock_init(&md->deferred_lock); | |
1961 | atomic_set(&md->holders, 1); | |
1962 | atomic_set(&md->open_count, 0); | |
1963 | atomic_set(&md->event_nr, 0); | |
1964 | atomic_set(&md->uevent_seq, 0); | |
1965 | INIT_LIST_HEAD(&md->uevent_list); | |
1966 | INIT_LIST_HEAD(&md->table_devices); | |
1967 | spin_lock_init(&md->uevent_lock); | |
1968 | ||
1969 | md->queue = blk_alloc_queue_node(GFP_KERNEL, numa_node_id); | |
1970 | if (!md->queue) | |
1971 | goto bad; | |
1972 | md->queue->queuedata = md; | |
1973 | md->queue->backing_dev_info->congested_data = md; | |
1974 | ||
1975 | md->disk = alloc_disk_node(1, md->numa_node_id); | |
1976 | if (!md->disk) | |
1977 | goto bad; | |
1978 | ||
1979 | init_waitqueue_head(&md->wait); | |
1980 | INIT_WORK(&md->work, dm_wq_work); | |
1981 | init_waitqueue_head(&md->eventq); | |
1982 | init_completion(&md->kobj_holder.completion); | |
1983 | ||
1984 | md->disk->major = _major; | |
1985 | md->disk->first_minor = minor; | |
1986 | md->disk->fops = &dm_blk_dops; | |
1987 | md->disk->queue = md->queue; | |
1988 | md->disk->private_data = md; | |
1989 | sprintf(md->disk->disk_name, "dm-%d", minor); | |
1990 | ||
1991 | if (IS_ENABLED(CONFIG_DAX_DRIVER)) { | |
1992 | md->dax_dev = alloc_dax(md, md->disk->disk_name, | |
1993 | &dm_dax_ops, 0); | |
1994 | if (!md->dax_dev) | |
1995 | goto bad; | |
1996 | } | |
1997 | ||
1998 | add_disk_no_queue_reg(md->disk); | |
1999 | format_dev_t(md->name, MKDEV(_major, minor)); | |
2000 | ||
2001 | md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0); | |
2002 | if (!md->wq) | |
2003 | goto bad; | |
2004 | ||
2005 | md->bdev = bdget_disk(md->disk, 0); | |
2006 | if (!md->bdev) | |
2007 | goto bad; | |
2008 | ||
2009 | dm_stats_init(&md->stats); | |
2010 | ||
2011 | /* Populate the mapping, nobody knows we exist yet */ | |
2012 | spin_lock(&_minor_lock); | |
2013 | old_md = idr_replace(&_minor_idr, md, minor); | |
2014 | spin_unlock(&_minor_lock); | |
2015 | ||
2016 | BUG_ON(old_md != MINOR_ALLOCED); | |
2017 | ||
2018 | return md; | |
2019 | ||
2020 | bad: | |
2021 | cleanup_mapped_device(md); | |
2022 | bad_io_barrier: | |
2023 | free_minor(minor); | |
2024 | bad_minor: | |
2025 | module_put(THIS_MODULE); | |
2026 | bad_module_get: | |
2027 | kvfree(md); | |
2028 | return NULL; | |
2029 | } | |
2030 | ||
2031 | static void unlock_fs(struct mapped_device *md); | |
2032 | ||
2033 | static void free_dev(struct mapped_device *md) | |
2034 | { | |
2035 | int minor = MINOR(disk_devt(md->disk)); | |
2036 | ||
2037 | unlock_fs(md); | |
2038 | ||
2039 | cleanup_mapped_device(md); | |
2040 | ||
2041 | free_table_devices(&md->table_devices); | |
2042 | dm_stats_cleanup(&md->stats); | |
2043 | free_minor(minor); | |
2044 | ||
2045 | module_put(THIS_MODULE); | |
2046 | kvfree(md); | |
2047 | } | |
2048 | ||
2049 | static int __bind_mempools(struct mapped_device *md, struct dm_table *t) | |
2050 | { | |
2051 | struct dm_md_mempools *p = dm_table_get_md_mempools(t); | |
2052 | int ret = 0; | |
2053 | ||
2054 | if (dm_table_bio_based(t)) { | |
2055 | /* | |
2056 | * The md may already have mempools that need changing. | |
2057 | * If so, reload bioset because front_pad may have changed | |
2058 | * because a different table was loaded. | |
2059 | */ | |
2060 | bioset_exit(&md->bs); | |
2061 | bioset_exit(&md->io_bs); | |
2062 | ||
2063 | } else if (bioset_initialized(&md->bs)) { | |
2064 | /* | |
2065 | * There's no need to reload with request-based dm | |
2066 | * because the size of front_pad doesn't change. | |
2067 | * Note for future: If you are to reload bioset, | |
2068 | * prep-ed requests in the queue may refer | |
2069 | * to bio from the old bioset, so you must walk | |
2070 | * through the queue to unprep. | |
2071 | */ | |
2072 | goto out; | |
2073 | } | |
2074 | ||
2075 | BUG_ON(!p || | |
2076 | bioset_initialized(&md->bs) || | |
2077 | bioset_initialized(&md->io_bs)); | |
2078 | ||
2079 | ret = bioset_init_from_src(&md->bs, &p->bs); | |
2080 | if (ret) | |
2081 | goto out; | |
2082 | ret = bioset_init_from_src(&md->io_bs, &p->io_bs); | |
2083 | if (ret) | |
2084 | bioset_exit(&md->bs); | |
2085 | out: | |
2086 | /* mempool bind completed, no longer need any mempools in the table */ | |
2087 | dm_table_free_md_mempools(t); | |
2088 | return ret; | |
2089 | } | |
2090 | ||
2091 | /* | |
2092 | * Bind a table to the device. | |
2093 | */ | |
2094 | static void event_callback(void *context) | |
2095 | { | |
2096 | unsigned long flags; | |
2097 | LIST_HEAD(uevents); | |
2098 | struct mapped_device *md = (struct mapped_device *) context; | |
2099 | ||
2100 | spin_lock_irqsave(&md->uevent_lock, flags); | |
2101 | list_splice_init(&md->uevent_list, &uevents); | |
2102 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2103 | ||
2104 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); | |
2105 | ||
2106 | atomic_inc(&md->event_nr); | |
2107 | wake_up(&md->eventq); | |
2108 | dm_issue_global_event(); | |
2109 | } | |
2110 | ||
2111 | /* | |
2112 | * Protected by md->suspend_lock obtained by dm_swap_table(). | |
2113 | */ | |
2114 | static void __set_size(struct mapped_device *md, sector_t size) | |
2115 | { | |
2116 | lockdep_assert_held(&md->suspend_lock); | |
2117 | ||
2118 | set_capacity(md->disk, size); | |
2119 | ||
2120 | i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); | |
2121 | } | |
2122 | ||
2123 | /* | |
2124 | * Returns old map, which caller must destroy. | |
2125 | */ | |
2126 | static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, | |
2127 | struct queue_limits *limits) | |
2128 | { | |
2129 | struct dm_table *old_map; | |
2130 | struct request_queue *q = md->queue; | |
2131 | bool request_based = dm_table_request_based(t); | |
2132 | sector_t size; | |
2133 | int ret; | |
2134 | ||
2135 | lockdep_assert_held(&md->suspend_lock); | |
2136 | ||
2137 | size = dm_table_get_size(t); | |
2138 | ||
2139 | /* | |
2140 | * Wipe any geometry if the size of the table changed. | |
2141 | */ | |
2142 | if (size != dm_get_size(md)) | |
2143 | memset(&md->geometry, 0, sizeof(md->geometry)); | |
2144 | ||
2145 | __set_size(md, size); | |
2146 | ||
2147 | dm_table_event_callback(t, event_callback, md); | |
2148 | ||
2149 | /* | |
2150 | * The queue hasn't been stopped yet, if the old table type wasn't | |
2151 | * for request-based during suspension. So stop it to prevent | |
2152 | * I/O mapping before resume. | |
2153 | * This must be done before setting the queue restrictions, | |
2154 | * because request-based dm may be run just after the setting. | |
2155 | */ | |
2156 | if (request_based) | |
2157 | dm_stop_queue(q); | |
2158 | ||
2159 | if (request_based || md->type == DM_TYPE_NVME_BIO_BASED) { | |
2160 | /* | |
2161 | * Leverage the fact that request-based DM targets and | |
2162 | * NVMe bio based targets are immutable singletons | |
2163 | * - used to optimize both dm_request_fn and dm_mq_queue_rq; | |
2164 | * and __process_bio. | |
2165 | */ | |
2166 | md->immutable_target = dm_table_get_immutable_target(t); | |
2167 | } | |
2168 | ||
2169 | ret = __bind_mempools(md, t); | |
2170 | if (ret) { | |
2171 | old_map = ERR_PTR(ret); | |
2172 | goto out; | |
2173 | } | |
2174 | ||
2175 | old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); | |
2176 | rcu_assign_pointer(md->map, (void *)t); | |
2177 | md->immutable_target_type = dm_table_get_immutable_target_type(t); | |
2178 | ||
2179 | dm_table_set_restrictions(t, q, limits); | |
2180 | if (old_map) | |
2181 | dm_sync_table(md); | |
2182 | ||
2183 | out: | |
2184 | return old_map; | |
2185 | } | |
2186 | ||
2187 | /* | |
2188 | * Returns unbound table for the caller to free. | |
2189 | */ | |
2190 | static struct dm_table *__unbind(struct mapped_device *md) | |
2191 | { | |
2192 | struct dm_table *map = rcu_dereference_protected(md->map, 1); | |
2193 | ||
2194 | if (!map) | |
2195 | return NULL; | |
2196 | ||
2197 | dm_table_event_callback(map, NULL, NULL); | |
2198 | RCU_INIT_POINTER(md->map, NULL); | |
2199 | dm_sync_table(md); | |
2200 | ||
2201 | return map; | |
2202 | } | |
2203 | ||
2204 | /* | |
2205 | * Constructor for a new device. | |
2206 | */ | |
2207 | int dm_create(int minor, struct mapped_device **result) | |
2208 | { | |
2209 | int r; | |
2210 | struct mapped_device *md; | |
2211 | ||
2212 | md = alloc_dev(minor); | |
2213 | if (!md) | |
2214 | return -ENXIO; | |
2215 | ||
2216 | r = dm_sysfs_init(md); | |
2217 | if (r) { | |
2218 | free_dev(md); | |
2219 | return r; | |
2220 | } | |
2221 | ||
2222 | *result = md; | |
2223 | return 0; | |
2224 | } | |
2225 | ||
2226 | /* | |
2227 | * Functions to manage md->type. | |
2228 | * All are required to hold md->type_lock. | |
2229 | */ | |
2230 | void dm_lock_md_type(struct mapped_device *md) | |
2231 | { | |
2232 | mutex_lock(&md->type_lock); | |
2233 | } | |
2234 | ||
2235 | void dm_unlock_md_type(struct mapped_device *md) | |
2236 | { | |
2237 | mutex_unlock(&md->type_lock); | |
2238 | } | |
2239 | ||
2240 | void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type) | |
2241 | { | |
2242 | BUG_ON(!mutex_is_locked(&md->type_lock)); | |
2243 | md->type = type; | |
2244 | } | |
2245 | ||
2246 | enum dm_queue_mode dm_get_md_type(struct mapped_device *md) | |
2247 | { | |
2248 | return md->type; | |
2249 | } | |
2250 | ||
2251 | struct target_type *dm_get_immutable_target_type(struct mapped_device *md) | |
2252 | { | |
2253 | return md->immutable_target_type; | |
2254 | } | |
2255 | ||
2256 | /* | |
2257 | * The queue_limits are only valid as long as you have a reference | |
2258 | * count on 'md'. | |
2259 | */ | |
2260 | struct queue_limits *dm_get_queue_limits(struct mapped_device *md) | |
2261 | { | |
2262 | BUG_ON(!atomic_read(&md->holders)); | |
2263 | return &md->queue->limits; | |
2264 | } | |
2265 | EXPORT_SYMBOL_GPL(dm_get_queue_limits); | |
2266 | ||
2267 | /* | |
2268 | * Setup the DM device's queue based on md's type | |
2269 | */ | |
2270 | int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t) | |
2271 | { | |
2272 | int r; | |
2273 | struct queue_limits limits; | |
2274 | enum dm_queue_mode type = dm_get_md_type(md); | |
2275 | ||
2276 | switch (type) { | |
2277 | case DM_TYPE_REQUEST_BASED: | |
2278 | r = dm_mq_init_request_queue(md, t); | |
2279 | if (r) { | |
2280 | DMERR("Cannot initialize queue for request-based dm-mq mapped device"); | |
2281 | return r; | |
2282 | } | |
2283 | break; | |
2284 | case DM_TYPE_BIO_BASED: | |
2285 | case DM_TYPE_DAX_BIO_BASED: | |
2286 | case DM_TYPE_NVME_BIO_BASED: | |
2287 | dm_init_normal_md_queue(md); | |
2288 | blk_queue_make_request(md->queue, dm_make_request); | |
2289 | break; | |
2290 | case DM_TYPE_NONE: | |
2291 | WARN_ON_ONCE(true); | |
2292 | break; | |
2293 | } | |
2294 | ||
2295 | r = dm_calculate_queue_limits(t, &limits); | |
2296 | if (r) { | |
2297 | DMERR("Cannot calculate initial queue limits"); | |
2298 | return r; | |
2299 | } | |
2300 | dm_table_set_restrictions(t, md->queue, &limits); | |
2301 | blk_register_queue(md->disk); | |
2302 | ||
2303 | return 0; | |
2304 | } | |
2305 | ||
2306 | struct mapped_device *dm_get_md(dev_t dev) | |
2307 | { | |
2308 | struct mapped_device *md; | |
2309 | unsigned minor = MINOR(dev); | |
2310 | ||
2311 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) | |
2312 | return NULL; | |
2313 | ||
2314 | spin_lock(&_minor_lock); | |
2315 | ||
2316 | md = idr_find(&_minor_idr, minor); | |
2317 | if (!md || md == MINOR_ALLOCED || (MINOR(disk_devt(dm_disk(md))) != minor) || | |
2318 | test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) { | |
2319 | md = NULL; | |
2320 | goto out; | |
2321 | } | |
2322 | dm_get(md); | |
2323 | out: | |
2324 | spin_unlock(&_minor_lock); | |
2325 | ||
2326 | return md; | |
2327 | } | |
2328 | EXPORT_SYMBOL_GPL(dm_get_md); | |
2329 | ||
2330 | void *dm_get_mdptr(struct mapped_device *md) | |
2331 | { | |
2332 | return md->interface_ptr; | |
2333 | } | |
2334 | ||
2335 | void dm_set_mdptr(struct mapped_device *md, void *ptr) | |
2336 | { | |
2337 | md->interface_ptr = ptr; | |
2338 | } | |
2339 | ||
2340 | void dm_get(struct mapped_device *md) | |
2341 | { | |
2342 | atomic_inc(&md->holders); | |
2343 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); | |
2344 | } | |
2345 | ||
2346 | int dm_hold(struct mapped_device *md) | |
2347 | { | |
2348 | spin_lock(&_minor_lock); | |
2349 | if (test_bit(DMF_FREEING, &md->flags)) { | |
2350 | spin_unlock(&_minor_lock); | |
2351 | return -EBUSY; | |
2352 | } | |
2353 | dm_get(md); | |
2354 | spin_unlock(&_minor_lock); | |
2355 | return 0; | |
2356 | } | |
2357 | EXPORT_SYMBOL_GPL(dm_hold); | |
2358 | ||
2359 | const char *dm_device_name(struct mapped_device *md) | |
2360 | { | |
2361 | return md->name; | |
2362 | } | |
2363 | EXPORT_SYMBOL_GPL(dm_device_name); | |
2364 | ||
2365 | static void __dm_destroy(struct mapped_device *md, bool wait) | |
2366 | { | |
2367 | struct dm_table *map; | |
2368 | int srcu_idx; | |
2369 | ||
2370 | might_sleep(); | |
2371 | ||
2372 | spin_lock(&_minor_lock); | |
2373 | idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); | |
2374 | set_bit(DMF_FREEING, &md->flags); | |
2375 | spin_unlock(&_minor_lock); | |
2376 | ||
2377 | blk_set_queue_dying(md->queue); | |
2378 | ||
2379 | /* | |
2380 | * Take suspend_lock so that presuspend and postsuspend methods | |
2381 | * do not race with internal suspend. | |
2382 | */ | |
2383 | mutex_lock(&md->suspend_lock); | |
2384 | map = dm_get_live_table(md, &srcu_idx); | |
2385 | if (!dm_suspended_md(md)) { | |
2386 | dm_table_presuspend_targets(map); | |
2387 | dm_table_postsuspend_targets(map); | |
2388 | } | |
2389 | /* dm_put_live_table must be before msleep, otherwise deadlock is possible */ | |
2390 | dm_put_live_table(md, srcu_idx); | |
2391 | mutex_unlock(&md->suspend_lock); | |
2392 | ||
2393 | /* | |
2394 | * Rare, but there may be I/O requests still going to complete, | |
2395 | * for example. Wait for all references to disappear. | |
2396 | * No one should increment the reference count of the mapped_device, | |
2397 | * after the mapped_device state becomes DMF_FREEING. | |
2398 | */ | |
2399 | if (wait) | |
2400 | while (atomic_read(&md->holders)) | |
2401 | msleep(1); | |
2402 | else if (atomic_read(&md->holders)) | |
2403 | DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", | |
2404 | dm_device_name(md), atomic_read(&md->holders)); | |
2405 | ||
2406 | dm_sysfs_exit(md); | |
2407 | dm_table_destroy(__unbind(md)); | |
2408 | free_dev(md); | |
2409 | } | |
2410 | ||
2411 | void dm_destroy(struct mapped_device *md) | |
2412 | { | |
2413 | __dm_destroy(md, true); | |
2414 | } | |
2415 | ||
2416 | void dm_destroy_immediate(struct mapped_device *md) | |
2417 | { | |
2418 | __dm_destroy(md, false); | |
2419 | } | |
2420 | ||
2421 | void dm_put(struct mapped_device *md) | |
2422 | { | |
2423 | atomic_dec(&md->holders); | |
2424 | } | |
2425 | EXPORT_SYMBOL_GPL(dm_put); | |
2426 | ||
2427 | static int dm_wait_for_completion(struct mapped_device *md, long task_state) | |
2428 | { | |
2429 | int r = 0; | |
2430 | DEFINE_WAIT(wait); | |
2431 | ||
2432 | while (1) { | |
2433 | prepare_to_wait(&md->wait, &wait, task_state); | |
2434 | ||
2435 | if (!md_in_flight(md)) | |
2436 | break; | |
2437 | ||
2438 | if (signal_pending_state(task_state, current)) { | |
2439 | r = -EINTR; | |
2440 | break; | |
2441 | } | |
2442 | ||
2443 | io_schedule(); | |
2444 | } | |
2445 | finish_wait(&md->wait, &wait); | |
2446 | ||
2447 | return r; | |
2448 | } | |
2449 | ||
2450 | /* | |
2451 | * Process the deferred bios | |
2452 | */ | |
2453 | static void dm_wq_work(struct work_struct *work) | |
2454 | { | |
2455 | struct mapped_device *md = container_of(work, struct mapped_device, | |
2456 | work); | |
2457 | struct bio *c; | |
2458 | int srcu_idx; | |
2459 | struct dm_table *map; | |
2460 | ||
2461 | map = dm_get_live_table(md, &srcu_idx); | |
2462 | ||
2463 | while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { | |
2464 | spin_lock_irq(&md->deferred_lock); | |
2465 | c = bio_list_pop(&md->deferred); | |
2466 | spin_unlock_irq(&md->deferred_lock); | |
2467 | ||
2468 | if (!c) | |
2469 | break; | |
2470 | ||
2471 | if (dm_request_based(md)) | |
2472 | (void) generic_make_request(c); | |
2473 | else | |
2474 | (void) dm_process_bio(md, map, c); | |
2475 | } | |
2476 | ||
2477 | dm_put_live_table(md, srcu_idx); | |
2478 | } | |
2479 | ||
2480 | static void dm_queue_flush(struct mapped_device *md) | |
2481 | { | |
2482 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); | |
2483 | smp_mb__after_atomic(); | |
2484 | queue_work(md->wq, &md->work); | |
2485 | } | |
2486 | ||
2487 | /* | |
2488 | * Swap in a new table, returning the old one for the caller to destroy. | |
2489 | */ | |
2490 | struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) | |
2491 | { | |
2492 | struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL); | |
2493 | struct queue_limits limits; | |
2494 | int r; | |
2495 | ||
2496 | mutex_lock(&md->suspend_lock); | |
2497 | ||
2498 | /* device must be suspended */ | |
2499 | if (!dm_suspended_md(md)) | |
2500 | goto out; | |
2501 | ||
2502 | /* | |
2503 | * If the new table has no data devices, retain the existing limits. | |
2504 | * This helps multipath with queue_if_no_path if all paths disappear, | |
2505 | * then new I/O is queued based on these limits, and then some paths | |
2506 | * reappear. | |
2507 | */ | |
2508 | if (dm_table_has_no_data_devices(table)) { | |
2509 | live_map = dm_get_live_table_fast(md); | |
2510 | if (live_map) | |
2511 | limits = md->queue->limits; | |
2512 | dm_put_live_table_fast(md); | |
2513 | } | |
2514 | ||
2515 | if (!live_map) { | |
2516 | r = dm_calculate_queue_limits(table, &limits); | |
2517 | if (r) { | |
2518 | map = ERR_PTR(r); | |
2519 | goto out; | |
2520 | } | |
2521 | } | |
2522 | ||
2523 | map = __bind(md, table, &limits); | |
2524 | dm_issue_global_event(); | |
2525 | ||
2526 | out: | |
2527 | mutex_unlock(&md->suspend_lock); | |
2528 | return map; | |
2529 | } | |
2530 | ||
2531 | /* | |
2532 | * Functions to lock and unlock any filesystem running on the | |
2533 | * device. | |
2534 | */ | |
2535 | static int lock_fs(struct mapped_device *md) | |
2536 | { | |
2537 | int r; | |
2538 | ||
2539 | WARN_ON(md->frozen_sb); | |
2540 | ||
2541 | md->frozen_sb = freeze_bdev(md->bdev); | |
2542 | if (IS_ERR(md->frozen_sb)) { | |
2543 | r = PTR_ERR(md->frozen_sb); | |
2544 | md->frozen_sb = NULL; | |
2545 | return r; | |
2546 | } | |
2547 | ||
2548 | set_bit(DMF_FROZEN, &md->flags); | |
2549 | ||
2550 | return 0; | |
2551 | } | |
2552 | ||
2553 | static void unlock_fs(struct mapped_device *md) | |
2554 | { | |
2555 | if (!test_bit(DMF_FROZEN, &md->flags)) | |
2556 | return; | |
2557 | ||
2558 | thaw_bdev(md->bdev, md->frozen_sb); | |
2559 | md->frozen_sb = NULL; | |
2560 | clear_bit(DMF_FROZEN, &md->flags); | |
2561 | } | |
2562 | ||
2563 | /* | |
2564 | * @suspend_flags: DM_SUSPEND_LOCKFS_FLAG and/or DM_SUSPEND_NOFLUSH_FLAG | |
2565 | * @task_state: e.g. TASK_INTERRUPTIBLE or TASK_UNINTERRUPTIBLE | |
2566 | * @dmf_suspended_flag: DMF_SUSPENDED or DMF_SUSPENDED_INTERNALLY | |
2567 | * | |
2568 | * If __dm_suspend returns 0, the device is completely quiescent | |
2569 | * now. There is no request-processing activity. All new requests | |
2570 | * are being added to md->deferred list. | |
2571 | */ | |
2572 | static int __dm_suspend(struct mapped_device *md, struct dm_table *map, | |
2573 | unsigned suspend_flags, long task_state, | |
2574 | int dmf_suspended_flag) | |
2575 | { | |
2576 | bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG; | |
2577 | bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG; | |
2578 | int r; | |
2579 | ||
2580 | lockdep_assert_held(&md->suspend_lock); | |
2581 | ||
2582 | /* | |
2583 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. | |
2584 | * This flag is cleared before dm_suspend returns. | |
2585 | */ | |
2586 | if (noflush) | |
2587 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
2588 | else | |
2589 | pr_debug("%s: suspending with flush\n", dm_device_name(md)); | |
2590 | ||
2591 | /* | |
2592 | * This gets reverted if there's an error later and the targets | |
2593 | * provide the .presuspend_undo hook. | |
2594 | */ | |
2595 | dm_table_presuspend_targets(map); | |
2596 | ||
2597 | /* | |
2598 | * Flush I/O to the device. | |
2599 | * Any I/O submitted after lock_fs() may not be flushed. | |
2600 | * noflush takes precedence over do_lockfs. | |
2601 | * (lock_fs() flushes I/Os and waits for them to complete.) | |
2602 | */ | |
2603 | if (!noflush && do_lockfs) { | |
2604 | r = lock_fs(md); | |
2605 | if (r) { | |
2606 | dm_table_presuspend_undo_targets(map); | |
2607 | return r; | |
2608 | } | |
2609 | } | |
2610 | ||
2611 | /* | |
2612 | * Here we must make sure that no processes are submitting requests | |
2613 | * to target drivers i.e. no one may be executing | |
2614 | * __split_and_process_bio. This is called from dm_request and | |
2615 | * dm_wq_work. | |
2616 | * | |
2617 | * To get all processes out of __split_and_process_bio in dm_request, | |
2618 | * we take the write lock. To prevent any process from reentering | |
2619 | * __split_and_process_bio from dm_request and quiesce the thread | |
2620 | * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call | |
2621 | * flush_workqueue(md->wq). | |
2622 | */ | |
2623 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); | |
2624 | if (map) | |
2625 | synchronize_srcu(&md->io_barrier); | |
2626 | ||
2627 | /* | |
2628 | * Stop md->queue before flushing md->wq in case request-based | |
2629 | * dm defers requests to md->wq from md->queue. | |
2630 | */ | |
2631 | if (dm_request_based(md)) | |
2632 | dm_stop_queue(md->queue); | |
2633 | ||
2634 | flush_workqueue(md->wq); | |
2635 | ||
2636 | /* | |
2637 | * At this point no more requests are entering target request routines. | |
2638 | * We call dm_wait_for_completion to wait for all existing requests | |
2639 | * to finish. | |
2640 | */ | |
2641 | r = dm_wait_for_completion(md, task_state); | |
2642 | if (!r) | |
2643 | set_bit(dmf_suspended_flag, &md->flags); | |
2644 | ||
2645 | if (noflush) | |
2646 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); | |
2647 | if (map) | |
2648 | synchronize_srcu(&md->io_barrier); | |
2649 | ||
2650 | /* were we interrupted ? */ | |
2651 | if (r < 0) { | |
2652 | dm_queue_flush(md); | |
2653 | ||
2654 | if (dm_request_based(md)) | |
2655 | dm_start_queue(md->queue); | |
2656 | ||
2657 | unlock_fs(md); | |
2658 | dm_table_presuspend_undo_targets(map); | |
2659 | /* pushback list is already flushed, so skip flush */ | |
2660 | } | |
2661 | ||
2662 | return r; | |
2663 | } | |
2664 | ||
2665 | /* | |
2666 | * We need to be able to change a mapping table under a mounted | |
2667 | * filesystem. For example we might want to move some data in | |
2668 | * the background. Before the table can be swapped with | |
2669 | * dm_bind_table, dm_suspend must be called to flush any in | |
2670 | * flight bios and ensure that any further io gets deferred. | |
2671 | */ | |
2672 | /* | |
2673 | * Suspend mechanism in request-based dm. | |
2674 | * | |
2675 | * 1. Flush all I/Os by lock_fs() if needed. | |
2676 | * 2. Stop dispatching any I/O by stopping the request_queue. | |
2677 | * 3. Wait for all in-flight I/Os to be completed or requeued. | |
2678 | * | |
2679 | * To abort suspend, start the request_queue. | |
2680 | */ | |
2681 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) | |
2682 | { | |
2683 | struct dm_table *map = NULL; | |
2684 | int r = 0; | |
2685 | ||
2686 | retry: | |
2687 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
2688 | ||
2689 | if (dm_suspended_md(md)) { | |
2690 | r = -EINVAL; | |
2691 | goto out_unlock; | |
2692 | } | |
2693 | ||
2694 | if (dm_suspended_internally_md(md)) { | |
2695 | /* already internally suspended, wait for internal resume */ | |
2696 | mutex_unlock(&md->suspend_lock); | |
2697 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
2698 | if (r) | |
2699 | return r; | |
2700 | goto retry; | |
2701 | } | |
2702 | ||
2703 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); | |
2704 | ||
2705 | r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE, DMF_SUSPENDED); | |
2706 | if (r) | |
2707 | goto out_unlock; | |
2708 | ||
2709 | dm_table_postsuspend_targets(map); | |
2710 | ||
2711 | out_unlock: | |
2712 | mutex_unlock(&md->suspend_lock); | |
2713 | return r; | |
2714 | } | |
2715 | ||
2716 | static int __dm_resume(struct mapped_device *md, struct dm_table *map) | |
2717 | { | |
2718 | if (map) { | |
2719 | int r = dm_table_resume_targets(map); | |
2720 | if (r) | |
2721 | return r; | |
2722 | } | |
2723 | ||
2724 | dm_queue_flush(md); | |
2725 | ||
2726 | /* | |
2727 | * Flushing deferred I/Os must be done after targets are resumed | |
2728 | * so that mapping of targets can work correctly. | |
2729 | * Request-based dm is queueing the deferred I/Os in its request_queue. | |
2730 | */ | |
2731 | if (dm_request_based(md)) | |
2732 | dm_start_queue(md->queue); | |
2733 | ||
2734 | unlock_fs(md); | |
2735 | ||
2736 | return 0; | |
2737 | } | |
2738 | ||
2739 | int dm_resume(struct mapped_device *md) | |
2740 | { | |
2741 | int r; | |
2742 | struct dm_table *map = NULL; | |
2743 | ||
2744 | retry: | |
2745 | r = -EINVAL; | |
2746 | mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); | |
2747 | ||
2748 | if (!dm_suspended_md(md)) | |
2749 | goto out; | |
2750 | ||
2751 | if (dm_suspended_internally_md(md)) { | |
2752 | /* already internally suspended, wait for internal resume */ | |
2753 | mutex_unlock(&md->suspend_lock); | |
2754 | r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); | |
2755 | if (r) | |
2756 | return r; | |
2757 | goto retry; | |
2758 | } | |
2759 | ||
2760 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); | |
2761 | if (!map || !dm_table_get_size(map)) | |
2762 | goto out; | |
2763 | ||
2764 | r = __dm_resume(md, map); | |
2765 | if (r) | |
2766 | goto out; | |
2767 | ||
2768 | clear_bit(DMF_SUSPENDED, &md->flags); | |
2769 | out: | |
2770 | mutex_unlock(&md->suspend_lock); | |
2771 | ||
2772 | return r; | |
2773 | } | |
2774 | ||
2775 | /* | |
2776 | * Internal suspend/resume works like userspace-driven suspend. It waits | |
2777 | * until all bios finish and prevents issuing new bios to the target drivers. | |
2778 | * It may be used only from the kernel. | |
2779 | */ | |
2780 | ||
2781 | static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags) | |
2782 | { | |
2783 | struct dm_table *map = NULL; | |
2784 | ||
2785 | lockdep_assert_held(&md->suspend_lock); | |
2786 | ||
2787 | if (md->internal_suspend_count++) | |
2788 | return; /* nested internal suspend */ | |
2789 | ||
2790 | if (dm_suspended_md(md)) { | |
2791 | set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
2792 | return; /* nest suspend */ | |
2793 | } | |
2794 | ||
2795 | map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); | |
2796 | ||
2797 | /* | |
2798 | * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is | |
2799 | * supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend | |
2800 | * would require changing .presuspend to return an error -- avoid this | |
2801 | * until there is a need for more elaborate variants of internal suspend. | |
2802 | */ | |
2803 | (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE, | |
2804 | DMF_SUSPENDED_INTERNALLY); | |
2805 | ||
2806 | dm_table_postsuspend_targets(map); | |
2807 | } | |
2808 | ||
2809 | static void __dm_internal_resume(struct mapped_device *md) | |
2810 | { | |
2811 | BUG_ON(!md->internal_suspend_count); | |
2812 | ||
2813 | if (--md->internal_suspend_count) | |
2814 | return; /* resume from nested internal suspend */ | |
2815 | ||
2816 | if (dm_suspended_md(md)) | |
2817 | goto done; /* resume from nested suspend */ | |
2818 | ||
2819 | /* | |
2820 | * NOTE: existing callers don't need to call dm_table_resume_targets | |
2821 | * (which may fail -- so best to avoid it for now by passing NULL map) | |
2822 | */ | |
2823 | (void) __dm_resume(md, NULL); | |
2824 | ||
2825 | done: | |
2826 | clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
2827 | smp_mb__after_atomic(); | |
2828 | wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY); | |
2829 | } | |
2830 | ||
2831 | void dm_internal_suspend_noflush(struct mapped_device *md) | |
2832 | { | |
2833 | mutex_lock(&md->suspend_lock); | |
2834 | __dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG); | |
2835 | mutex_unlock(&md->suspend_lock); | |
2836 | } | |
2837 | EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush); | |
2838 | ||
2839 | void dm_internal_resume(struct mapped_device *md) | |
2840 | { | |
2841 | mutex_lock(&md->suspend_lock); | |
2842 | __dm_internal_resume(md); | |
2843 | mutex_unlock(&md->suspend_lock); | |
2844 | } | |
2845 | EXPORT_SYMBOL_GPL(dm_internal_resume); | |
2846 | ||
2847 | /* | |
2848 | * Fast variants of internal suspend/resume hold md->suspend_lock, | |
2849 | * which prevents interaction with userspace-driven suspend. | |
2850 | */ | |
2851 | ||
2852 | void dm_internal_suspend_fast(struct mapped_device *md) | |
2853 | { | |
2854 | mutex_lock(&md->suspend_lock); | |
2855 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) | |
2856 | return; | |
2857 | ||
2858 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); | |
2859 | synchronize_srcu(&md->io_barrier); | |
2860 | flush_workqueue(md->wq); | |
2861 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); | |
2862 | } | |
2863 | EXPORT_SYMBOL_GPL(dm_internal_suspend_fast); | |
2864 | ||
2865 | void dm_internal_resume_fast(struct mapped_device *md) | |
2866 | { | |
2867 | if (dm_suspended_md(md) || dm_suspended_internally_md(md)) | |
2868 | goto done; | |
2869 | ||
2870 | dm_queue_flush(md); | |
2871 | ||
2872 | done: | |
2873 | mutex_unlock(&md->suspend_lock); | |
2874 | } | |
2875 | EXPORT_SYMBOL_GPL(dm_internal_resume_fast); | |
2876 | ||
2877 | /*----------------------------------------------------------------- | |
2878 | * Event notification. | |
2879 | *---------------------------------------------------------------*/ | |
2880 | int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, | |
2881 | unsigned cookie) | |
2882 | { | |
2883 | char udev_cookie[DM_COOKIE_LENGTH]; | |
2884 | char *envp[] = { udev_cookie, NULL }; | |
2885 | ||
2886 | if (!cookie) | |
2887 | return kobject_uevent(&disk_to_dev(md->disk)->kobj, action); | |
2888 | else { | |
2889 | snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", | |
2890 | DM_COOKIE_ENV_VAR_NAME, cookie); | |
2891 | return kobject_uevent_env(&disk_to_dev(md->disk)->kobj, | |
2892 | action, envp); | |
2893 | } | |
2894 | } | |
2895 | ||
2896 | uint32_t dm_next_uevent_seq(struct mapped_device *md) | |
2897 | { | |
2898 | return atomic_add_return(1, &md->uevent_seq); | |
2899 | } | |
2900 | ||
2901 | uint32_t dm_get_event_nr(struct mapped_device *md) | |
2902 | { | |
2903 | return atomic_read(&md->event_nr); | |
2904 | } | |
2905 | ||
2906 | int dm_wait_event(struct mapped_device *md, int event_nr) | |
2907 | { | |
2908 | return wait_event_interruptible(md->eventq, | |
2909 | (event_nr != atomic_read(&md->event_nr))); | |
2910 | } | |
2911 | ||
2912 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) | |
2913 | { | |
2914 | unsigned long flags; | |
2915 | ||
2916 | spin_lock_irqsave(&md->uevent_lock, flags); | |
2917 | list_add(elist, &md->uevent_list); | |
2918 | spin_unlock_irqrestore(&md->uevent_lock, flags); | |
2919 | } | |
2920 | ||
2921 | /* | |
2922 | * The gendisk is only valid as long as you have a reference | |
2923 | * count on 'md'. | |
2924 | */ | |
2925 | struct gendisk *dm_disk(struct mapped_device *md) | |
2926 | { | |
2927 | return md->disk; | |
2928 | } | |
2929 | EXPORT_SYMBOL_GPL(dm_disk); | |
2930 | ||
2931 | struct kobject *dm_kobject(struct mapped_device *md) | |
2932 | { | |
2933 | return &md->kobj_holder.kobj; | |
2934 | } | |
2935 | ||
2936 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) | |
2937 | { | |
2938 | struct mapped_device *md; | |
2939 | ||
2940 | md = container_of(kobj, struct mapped_device, kobj_holder.kobj); | |
2941 | ||
2942 | spin_lock(&_minor_lock); | |
2943 | if (test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) { | |
2944 | md = NULL; | |
2945 | goto out; | |
2946 | } | |
2947 | dm_get(md); | |
2948 | out: | |
2949 | spin_unlock(&_minor_lock); | |
2950 | ||
2951 | return md; | |
2952 | } | |
2953 | ||
2954 | int dm_suspended_md(struct mapped_device *md) | |
2955 | { | |
2956 | return test_bit(DMF_SUSPENDED, &md->flags); | |
2957 | } | |
2958 | ||
2959 | int dm_suspended_internally_md(struct mapped_device *md) | |
2960 | { | |
2961 | return test_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); | |
2962 | } | |
2963 | ||
2964 | int dm_test_deferred_remove_flag(struct mapped_device *md) | |
2965 | { | |
2966 | return test_bit(DMF_DEFERRED_REMOVE, &md->flags); | |
2967 | } | |
2968 | ||
2969 | int dm_suspended(struct dm_target *ti) | |
2970 | { | |
2971 | return dm_suspended_md(dm_table_get_md(ti->table)); | |
2972 | } | |
2973 | EXPORT_SYMBOL_GPL(dm_suspended); | |
2974 | ||
2975 | int dm_noflush_suspending(struct dm_target *ti) | |
2976 | { | |
2977 | return __noflush_suspending(dm_table_get_md(ti->table)); | |
2978 | } | |
2979 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); | |
2980 | ||
2981 | struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type, | |
2982 | unsigned integrity, unsigned per_io_data_size, | |
2983 | unsigned min_pool_size) | |
2984 | { | |
2985 | struct dm_md_mempools *pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id); | |
2986 | unsigned int pool_size = 0; | |
2987 | unsigned int front_pad, io_front_pad; | |
2988 | int ret; | |
2989 | ||
2990 | if (!pools) | |
2991 | return NULL; | |
2992 | ||
2993 | switch (type) { | |
2994 | case DM_TYPE_BIO_BASED: | |
2995 | case DM_TYPE_DAX_BIO_BASED: | |
2996 | case DM_TYPE_NVME_BIO_BASED: | |
2997 | pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size); | |
2998 | front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone); | |
2999 | io_front_pad = roundup(front_pad, __alignof__(struct dm_io)) + offsetof(struct dm_io, tio); | |
3000 | ret = bioset_init(&pools->io_bs, pool_size, io_front_pad, 0); | |
3001 | if (ret) | |
3002 | goto out; | |
3003 | if (integrity && bioset_integrity_create(&pools->io_bs, pool_size)) | |
3004 | goto out; | |
3005 | break; | |
3006 | case DM_TYPE_REQUEST_BASED: | |
3007 | pool_size = max(dm_get_reserved_rq_based_ios(), min_pool_size); | |
3008 | front_pad = offsetof(struct dm_rq_clone_bio_info, clone); | |
3009 | /* per_io_data_size is used for blk-mq pdu at queue allocation */ | |
3010 | break; | |
3011 | default: | |
3012 | BUG(); | |
3013 | } | |
3014 | ||
3015 | ret = bioset_init(&pools->bs, pool_size, front_pad, 0); | |
3016 | if (ret) | |
3017 | goto out; | |
3018 | ||
3019 | if (integrity && bioset_integrity_create(&pools->bs, pool_size)) | |
3020 | goto out; | |
3021 | ||
3022 | return pools; | |
3023 | ||
3024 | out: | |
3025 | dm_free_md_mempools(pools); | |
3026 | ||
3027 | return NULL; | |
3028 | } | |
3029 | ||
3030 | void dm_free_md_mempools(struct dm_md_mempools *pools) | |
3031 | { | |
3032 | if (!pools) | |
3033 | return; | |
3034 | ||
3035 | bioset_exit(&pools->bs); | |
3036 | bioset_exit(&pools->io_bs); | |
3037 | ||
3038 | kfree(pools); | |
3039 | } | |
3040 | ||
3041 | struct dm_pr { | |
3042 | u64 old_key; | |
3043 | u64 new_key; | |
3044 | u32 flags; | |
3045 | bool fail_early; | |
3046 | }; | |
3047 | ||
3048 | static int dm_call_pr(struct block_device *bdev, iterate_devices_callout_fn fn, | |
3049 | void *data) | |
3050 | { | |
3051 | struct mapped_device *md = bdev->bd_disk->private_data; | |
3052 | struct dm_table *table; | |
3053 | struct dm_target *ti; | |
3054 | int ret = -ENOTTY, srcu_idx; | |
3055 | ||
3056 | table = dm_get_live_table(md, &srcu_idx); | |
3057 | if (!table || !dm_table_get_size(table)) | |
3058 | goto out; | |
3059 | ||
3060 | /* We only support devices that have a single target */ | |
3061 | if (dm_table_get_num_targets(table) != 1) | |
3062 | goto out; | |
3063 | ti = dm_table_get_target(table, 0); | |
3064 | ||
3065 | ret = -EINVAL; | |
3066 | if (!ti->type->iterate_devices) | |
3067 | goto out; | |
3068 | ||
3069 | ret = ti->type->iterate_devices(ti, fn, data); | |
3070 | out: | |
3071 | dm_put_live_table(md, srcu_idx); | |
3072 | return ret; | |
3073 | } | |
3074 | ||
3075 | /* | |
3076 | * For register / unregister we need to manually call out to every path. | |
3077 | */ | |
3078 | static int __dm_pr_register(struct dm_target *ti, struct dm_dev *dev, | |
3079 | sector_t start, sector_t len, void *data) | |
3080 | { | |
3081 | struct dm_pr *pr = data; | |
3082 | const struct pr_ops *ops = dev->bdev->bd_disk->fops->pr_ops; | |
3083 | ||
3084 | if (!ops || !ops->pr_register) | |
3085 | return -EOPNOTSUPP; | |
3086 | return ops->pr_register(dev->bdev, pr->old_key, pr->new_key, pr->flags); | |
3087 | } | |
3088 | ||
3089 | static int dm_pr_register(struct block_device *bdev, u64 old_key, u64 new_key, | |
3090 | u32 flags) | |
3091 | { | |
3092 | struct dm_pr pr = { | |
3093 | .old_key = old_key, | |
3094 | .new_key = new_key, | |
3095 | .flags = flags, | |
3096 | .fail_early = true, | |
3097 | }; | |
3098 | int ret; | |
3099 | ||
3100 | ret = dm_call_pr(bdev, __dm_pr_register, &pr); | |
3101 | if (ret && new_key) { | |
3102 | /* unregister all paths if we failed to register any path */ | |
3103 | pr.old_key = new_key; | |
3104 | pr.new_key = 0; | |
3105 | pr.flags = 0; | |
3106 | pr.fail_early = false; | |
3107 | dm_call_pr(bdev, __dm_pr_register, &pr); | |
3108 | } | |
3109 | ||
3110 | return ret; | |
3111 | } | |
3112 | ||
3113 | static int dm_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type, | |
3114 | u32 flags) | |
3115 | { | |
3116 | struct mapped_device *md = bdev->bd_disk->private_data; | |
3117 | const struct pr_ops *ops; | |
3118 | int r, srcu_idx; | |
3119 | ||
3120 | r = dm_prepare_ioctl(md, &srcu_idx, &bdev); | |
3121 | if (r < 0) | |
3122 | goto out; | |
3123 | ||
3124 | ops = bdev->bd_disk->fops->pr_ops; | |
3125 | if (ops && ops->pr_reserve) | |
3126 | r = ops->pr_reserve(bdev, key, type, flags); | |
3127 | else | |
3128 | r = -EOPNOTSUPP; | |
3129 | out: | |
3130 | dm_unprepare_ioctl(md, srcu_idx); | |
3131 | return r; | |
3132 | } | |
3133 | ||
3134 | static int dm_pr_release(struct block_device *bdev, u64 key, enum pr_type type) | |
3135 | { | |
3136 | struct mapped_device *md = bdev->bd_disk->private_data; | |
3137 | const struct pr_ops *ops; | |
3138 | int r, srcu_idx; | |
3139 | ||
3140 | r = dm_prepare_ioctl(md, &srcu_idx, &bdev); | |
3141 | if (r < 0) | |
3142 | goto out; | |
3143 | ||
3144 | ops = bdev->bd_disk->fops->pr_ops; | |
3145 | if (ops && ops->pr_release) | |
3146 | r = ops->pr_release(bdev, key, type); | |
3147 | else | |
3148 | r = -EOPNOTSUPP; | |
3149 | out: | |
3150 | dm_unprepare_ioctl(md, srcu_idx); | |
3151 | return r; | |
3152 | } | |
3153 | ||
3154 | static int dm_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key, | |
3155 | enum pr_type type, bool abort) | |
3156 | { | |
3157 | struct mapped_device *md = bdev->bd_disk->private_data; | |
3158 | const struct pr_ops *ops; | |
3159 | int r, srcu_idx; | |
3160 | ||
3161 | r = dm_prepare_ioctl(md, &srcu_idx, &bdev); | |
3162 | if (r < 0) | |
3163 | goto out; | |
3164 | ||
3165 | ops = bdev->bd_disk->fops->pr_ops; | |
3166 | if (ops && ops->pr_preempt) | |
3167 | r = ops->pr_preempt(bdev, old_key, new_key, type, abort); | |
3168 | else | |
3169 | r = -EOPNOTSUPP; | |
3170 | out: | |
3171 | dm_unprepare_ioctl(md, srcu_idx); | |
3172 | return r; | |
3173 | } | |
3174 | ||
3175 | static int dm_pr_clear(struct block_device *bdev, u64 key) | |
3176 | { | |
3177 | struct mapped_device *md = bdev->bd_disk->private_data; | |
3178 | const struct pr_ops *ops; | |
3179 | int r, srcu_idx; | |
3180 | ||
3181 | r = dm_prepare_ioctl(md, &srcu_idx, &bdev); | |
3182 | if (r < 0) | |
3183 | goto out; | |
3184 | ||
3185 | ops = bdev->bd_disk->fops->pr_ops; | |
3186 | if (ops && ops->pr_clear) | |
3187 | r = ops->pr_clear(bdev, key); | |
3188 | else | |
3189 | r = -EOPNOTSUPP; | |
3190 | out: | |
3191 | dm_unprepare_ioctl(md, srcu_idx); | |
3192 | return r; | |
3193 | } | |
3194 | ||
3195 | static const struct pr_ops dm_pr_ops = { | |
3196 | .pr_register = dm_pr_register, | |
3197 | .pr_reserve = dm_pr_reserve, | |
3198 | .pr_release = dm_pr_release, | |
3199 | .pr_preempt = dm_pr_preempt, | |
3200 | .pr_clear = dm_pr_clear, | |
3201 | }; | |
3202 | ||
3203 | static const struct block_device_operations dm_blk_dops = { | |
3204 | .open = dm_blk_open, | |
3205 | .release = dm_blk_close, | |
3206 | .ioctl = dm_blk_ioctl, | |
3207 | .getgeo = dm_blk_getgeo, | |
3208 | .report_zones = dm_blk_report_zones, | |
3209 | .pr_ops = &dm_pr_ops, | |
3210 | .owner = THIS_MODULE | |
3211 | }; | |
3212 | ||
3213 | static const struct dax_operations dm_dax_ops = { | |
3214 | .direct_access = dm_dax_direct_access, | |
3215 | .dax_supported = dm_dax_supported, | |
3216 | .copy_from_iter = dm_dax_copy_from_iter, | |
3217 | .copy_to_iter = dm_dax_copy_to_iter, | |
3218 | }; | |
3219 | ||
3220 | /* | |
3221 | * module hooks | |
3222 | */ | |
3223 | module_init(dm_init); | |
3224 | module_exit(dm_exit); | |
3225 | ||
3226 | module_param(major, uint, 0); | |
3227 | MODULE_PARM_DESC(major, "The major number of the device mapper"); | |
3228 | ||
3229 | module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR); | |
3230 | MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools"); | |
3231 | ||
3232 | module_param(dm_numa_node, int, S_IRUGO | S_IWUSR); | |
3233 | MODULE_PARM_DESC(dm_numa_node, "NUMA node for DM device memory allocations"); | |
3234 | ||
3235 | MODULE_DESCRIPTION(DM_NAME " driver"); | |
3236 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
3237 | MODULE_LICENSE("GPL"); |