Loading...
1/*
2 * Copyright (C) 2001 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.h"
9
10#include <linux/module.h>
11#include <linux/vmalloc.h>
12#include <linux/blkdev.h>
13#include <linux/namei.h>
14#include <linux/ctype.h>
15#include <linux/string.h>
16#include <linux/slab.h>
17#include <linux/interrupt.h>
18#include <linux/mutex.h>
19#include <linux/delay.h>
20#include <linux/atomic.h>
21
22#define DM_MSG_PREFIX "table"
23
24#define MAX_DEPTH 16
25#define NODE_SIZE L1_CACHE_BYTES
26#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
27#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
28
29/*
30 * The table has always exactly one reference from either mapped_device->map
31 * or hash_cell->new_map. This reference is not counted in table->holders.
32 * A pair of dm_create_table/dm_destroy_table functions is used for table
33 * creation/destruction.
34 *
35 * Temporary references from the other code increase table->holders. A pair
36 * of dm_table_get/dm_table_put functions is used to manipulate it.
37 *
38 * When the table is about to be destroyed, we wait for table->holders to
39 * drop to zero.
40 */
41
42struct dm_table {
43 struct mapped_device *md;
44 atomic_t holders;
45 unsigned type;
46
47 /* btree table */
48 unsigned int depth;
49 unsigned int counts[MAX_DEPTH]; /* in nodes */
50 sector_t *index[MAX_DEPTH];
51
52 unsigned int num_targets;
53 unsigned int num_allocated;
54 sector_t *highs;
55 struct dm_target *targets;
56
57 unsigned integrity_supported:1;
58
59 /*
60 * Indicates the rw permissions for the new logical
61 * device. This should be a combination of FMODE_READ
62 * and FMODE_WRITE.
63 */
64 fmode_t mode;
65
66 /* a list of devices used by this table */
67 struct list_head devices;
68
69 /* events get handed up using this callback */
70 void (*event_fn)(void *);
71 void *event_context;
72
73 struct dm_md_mempools *mempools;
74
75 struct list_head target_callbacks;
76};
77
78/*
79 * Similar to ceiling(log_size(n))
80 */
81static unsigned int int_log(unsigned int n, unsigned int base)
82{
83 int result = 0;
84
85 while (n > 1) {
86 n = dm_div_up(n, base);
87 result++;
88 }
89
90 return result;
91}
92
93/*
94 * Calculate the index of the child node of the n'th node k'th key.
95 */
96static inline unsigned int get_child(unsigned int n, unsigned int k)
97{
98 return (n * CHILDREN_PER_NODE) + k;
99}
100
101/*
102 * Return the n'th node of level l from table t.
103 */
104static inline sector_t *get_node(struct dm_table *t,
105 unsigned int l, unsigned int n)
106{
107 return t->index[l] + (n * KEYS_PER_NODE);
108}
109
110/*
111 * Return the highest key that you could lookup from the n'th
112 * node on level l of the btree.
113 */
114static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
115{
116 for (; l < t->depth - 1; l++)
117 n = get_child(n, CHILDREN_PER_NODE - 1);
118
119 if (n >= t->counts[l])
120 return (sector_t) - 1;
121
122 return get_node(t, l, n)[KEYS_PER_NODE - 1];
123}
124
125/*
126 * Fills in a level of the btree based on the highs of the level
127 * below it.
128 */
129static int setup_btree_index(unsigned int l, struct dm_table *t)
130{
131 unsigned int n, k;
132 sector_t *node;
133
134 for (n = 0U; n < t->counts[l]; n++) {
135 node = get_node(t, l, n);
136
137 for (k = 0U; k < KEYS_PER_NODE; k++)
138 node[k] = high(t, l + 1, get_child(n, k));
139 }
140
141 return 0;
142}
143
144void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
145{
146 unsigned long size;
147 void *addr;
148
149 /*
150 * Check that we're not going to overflow.
151 */
152 if (nmemb > (ULONG_MAX / elem_size))
153 return NULL;
154
155 size = nmemb * elem_size;
156 addr = vzalloc(size);
157
158 return addr;
159}
160EXPORT_SYMBOL(dm_vcalloc);
161
162/*
163 * highs, and targets are managed as dynamic arrays during a
164 * table load.
165 */
166static int alloc_targets(struct dm_table *t, unsigned int num)
167{
168 sector_t *n_highs;
169 struct dm_target *n_targets;
170 int n = t->num_targets;
171
172 /*
173 * Allocate both the target array and offset array at once.
174 * Append an empty entry to catch sectors beyond the end of
175 * the device.
176 */
177 n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
178 sizeof(sector_t));
179 if (!n_highs)
180 return -ENOMEM;
181
182 n_targets = (struct dm_target *) (n_highs + num);
183
184 if (n) {
185 memcpy(n_highs, t->highs, sizeof(*n_highs) * n);
186 memcpy(n_targets, t->targets, sizeof(*n_targets) * n);
187 }
188
189 memset(n_highs + n, -1, sizeof(*n_highs) * (num - n));
190 vfree(t->highs);
191
192 t->num_allocated = num;
193 t->highs = n_highs;
194 t->targets = n_targets;
195
196 return 0;
197}
198
199int dm_table_create(struct dm_table **result, fmode_t mode,
200 unsigned num_targets, struct mapped_device *md)
201{
202 struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
203
204 if (!t)
205 return -ENOMEM;
206
207 INIT_LIST_HEAD(&t->devices);
208 INIT_LIST_HEAD(&t->target_callbacks);
209 atomic_set(&t->holders, 0);
210
211 if (!num_targets)
212 num_targets = KEYS_PER_NODE;
213
214 num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
215
216 if (alloc_targets(t, num_targets)) {
217 kfree(t);
218 t = NULL;
219 return -ENOMEM;
220 }
221
222 t->mode = mode;
223 t->md = md;
224 *result = t;
225 return 0;
226}
227
228static void free_devices(struct list_head *devices)
229{
230 struct list_head *tmp, *next;
231
232 list_for_each_safe(tmp, next, devices) {
233 struct dm_dev_internal *dd =
234 list_entry(tmp, struct dm_dev_internal, list);
235 DMWARN("dm_table_destroy: dm_put_device call missing for %s",
236 dd->dm_dev.name);
237 kfree(dd);
238 }
239}
240
241void dm_table_destroy(struct dm_table *t)
242{
243 unsigned int i;
244
245 if (!t)
246 return;
247
248 while (atomic_read(&t->holders))
249 msleep(1);
250 smp_mb();
251
252 /* free the indexes */
253 if (t->depth >= 2)
254 vfree(t->index[t->depth - 2]);
255
256 /* free the targets */
257 for (i = 0; i < t->num_targets; i++) {
258 struct dm_target *tgt = t->targets + i;
259
260 if (tgt->type->dtr)
261 tgt->type->dtr(tgt);
262
263 dm_put_target_type(tgt->type);
264 }
265
266 vfree(t->highs);
267
268 /* free the device list */
269 if (t->devices.next != &t->devices)
270 free_devices(&t->devices);
271
272 dm_free_md_mempools(t->mempools);
273
274 kfree(t);
275}
276
277void dm_table_get(struct dm_table *t)
278{
279 atomic_inc(&t->holders);
280}
281EXPORT_SYMBOL(dm_table_get);
282
283void dm_table_put(struct dm_table *t)
284{
285 if (!t)
286 return;
287
288 smp_mb__before_atomic_dec();
289 atomic_dec(&t->holders);
290}
291EXPORT_SYMBOL(dm_table_put);
292
293/*
294 * Checks to see if we need to extend highs or targets.
295 */
296static inline int check_space(struct dm_table *t)
297{
298 if (t->num_targets >= t->num_allocated)
299 return alloc_targets(t, t->num_allocated * 2);
300
301 return 0;
302}
303
304/*
305 * See if we've already got a device in the list.
306 */
307static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
308{
309 struct dm_dev_internal *dd;
310
311 list_for_each_entry (dd, l, list)
312 if (dd->dm_dev.bdev->bd_dev == dev)
313 return dd;
314
315 return NULL;
316}
317
318/*
319 * Open a device so we can use it as a map destination.
320 */
321static int open_dev(struct dm_dev_internal *d, dev_t dev,
322 struct mapped_device *md)
323{
324 static char *_claim_ptr = "I belong to device-mapper";
325 struct block_device *bdev;
326
327 int r;
328
329 BUG_ON(d->dm_dev.bdev);
330
331 bdev = blkdev_get_by_dev(dev, d->dm_dev.mode | FMODE_EXCL, _claim_ptr);
332 if (IS_ERR(bdev))
333 return PTR_ERR(bdev);
334
335 r = bd_link_disk_holder(bdev, dm_disk(md));
336 if (r) {
337 blkdev_put(bdev, d->dm_dev.mode | FMODE_EXCL);
338 return r;
339 }
340
341 d->dm_dev.bdev = bdev;
342 return 0;
343}
344
345/*
346 * Close a device that we've been using.
347 */
348static void close_dev(struct dm_dev_internal *d, struct mapped_device *md)
349{
350 if (!d->dm_dev.bdev)
351 return;
352
353 bd_unlink_disk_holder(d->dm_dev.bdev, dm_disk(md));
354 blkdev_put(d->dm_dev.bdev, d->dm_dev.mode | FMODE_EXCL);
355 d->dm_dev.bdev = NULL;
356}
357
358/*
359 * If possible, this checks an area of a destination device is invalid.
360 */
361static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
362 sector_t start, sector_t len, void *data)
363{
364 struct request_queue *q;
365 struct queue_limits *limits = data;
366 struct block_device *bdev = dev->bdev;
367 sector_t dev_size =
368 i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
369 unsigned short logical_block_size_sectors =
370 limits->logical_block_size >> SECTOR_SHIFT;
371 char b[BDEVNAME_SIZE];
372
373 /*
374 * Some devices exist without request functions,
375 * such as loop devices not yet bound to backing files.
376 * Forbid the use of such devices.
377 */
378 q = bdev_get_queue(bdev);
379 if (!q || !q->make_request_fn) {
380 DMWARN("%s: %s is not yet initialised: "
381 "start=%llu, len=%llu, dev_size=%llu",
382 dm_device_name(ti->table->md), bdevname(bdev, b),
383 (unsigned long long)start,
384 (unsigned long long)len,
385 (unsigned long long)dev_size);
386 return 1;
387 }
388
389 if (!dev_size)
390 return 0;
391
392 if ((start >= dev_size) || (start + len > dev_size)) {
393 DMWARN("%s: %s too small for target: "
394 "start=%llu, len=%llu, dev_size=%llu",
395 dm_device_name(ti->table->md), bdevname(bdev, b),
396 (unsigned long long)start,
397 (unsigned long long)len,
398 (unsigned long long)dev_size);
399 return 1;
400 }
401
402 if (logical_block_size_sectors <= 1)
403 return 0;
404
405 if (start & (logical_block_size_sectors - 1)) {
406 DMWARN("%s: start=%llu not aligned to h/w "
407 "logical block size %u of %s",
408 dm_device_name(ti->table->md),
409 (unsigned long long)start,
410 limits->logical_block_size, bdevname(bdev, b));
411 return 1;
412 }
413
414 if (len & (logical_block_size_sectors - 1)) {
415 DMWARN("%s: len=%llu not aligned to h/w "
416 "logical block size %u of %s",
417 dm_device_name(ti->table->md),
418 (unsigned long long)len,
419 limits->logical_block_size, bdevname(bdev, b));
420 return 1;
421 }
422
423 return 0;
424}
425
426/*
427 * This upgrades the mode on an already open dm_dev, being
428 * careful to leave things as they were if we fail to reopen the
429 * device and not to touch the existing bdev field in case
430 * it is accessed concurrently inside dm_table_any_congested().
431 */
432static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
433 struct mapped_device *md)
434{
435 int r;
436 struct dm_dev_internal dd_new, dd_old;
437
438 dd_new = dd_old = *dd;
439
440 dd_new.dm_dev.mode |= new_mode;
441 dd_new.dm_dev.bdev = NULL;
442
443 r = open_dev(&dd_new, dd->dm_dev.bdev->bd_dev, md);
444 if (r)
445 return r;
446
447 dd->dm_dev.mode |= new_mode;
448 close_dev(&dd_old, md);
449
450 return 0;
451}
452
453/*
454 * Add a device to the list, or just increment the usage count if
455 * it's already present.
456 */
457int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
458 struct dm_dev **result)
459{
460 int r;
461 dev_t uninitialized_var(dev);
462 struct dm_dev_internal *dd;
463 unsigned int major, minor;
464 struct dm_table *t = ti->table;
465
466 BUG_ON(!t);
467
468 if (sscanf(path, "%u:%u", &major, &minor) == 2) {
469 /* Extract the major/minor numbers */
470 dev = MKDEV(major, minor);
471 if (MAJOR(dev) != major || MINOR(dev) != minor)
472 return -EOVERFLOW;
473 } else {
474 /* convert the path to a device */
475 struct block_device *bdev = lookup_bdev(path);
476
477 if (IS_ERR(bdev))
478 return PTR_ERR(bdev);
479 dev = bdev->bd_dev;
480 bdput(bdev);
481 }
482
483 dd = find_device(&t->devices, dev);
484 if (!dd) {
485 dd = kmalloc(sizeof(*dd), GFP_KERNEL);
486 if (!dd)
487 return -ENOMEM;
488
489 dd->dm_dev.mode = mode;
490 dd->dm_dev.bdev = NULL;
491
492 if ((r = open_dev(dd, dev, t->md))) {
493 kfree(dd);
494 return r;
495 }
496
497 format_dev_t(dd->dm_dev.name, dev);
498
499 atomic_set(&dd->count, 0);
500 list_add(&dd->list, &t->devices);
501
502 } else if (dd->dm_dev.mode != (mode | dd->dm_dev.mode)) {
503 r = upgrade_mode(dd, mode, t->md);
504 if (r)
505 return r;
506 }
507 atomic_inc(&dd->count);
508
509 *result = &dd->dm_dev;
510 return 0;
511}
512EXPORT_SYMBOL(dm_get_device);
513
514int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
515 sector_t start, sector_t len, void *data)
516{
517 struct queue_limits *limits = data;
518 struct block_device *bdev = dev->bdev;
519 struct request_queue *q = bdev_get_queue(bdev);
520 char b[BDEVNAME_SIZE];
521
522 if (unlikely(!q)) {
523 DMWARN("%s: Cannot set limits for nonexistent device %s",
524 dm_device_name(ti->table->md), bdevname(bdev, b));
525 return 0;
526 }
527
528 if (bdev_stack_limits(limits, bdev, start) < 0)
529 DMWARN("%s: adding target device %s caused an alignment inconsistency: "
530 "physical_block_size=%u, logical_block_size=%u, "
531 "alignment_offset=%u, start=%llu",
532 dm_device_name(ti->table->md), bdevname(bdev, b),
533 q->limits.physical_block_size,
534 q->limits.logical_block_size,
535 q->limits.alignment_offset,
536 (unsigned long long) start << SECTOR_SHIFT);
537
538 /*
539 * Check if merge fn is supported.
540 * If not we'll force DM to use PAGE_SIZE or
541 * smaller I/O, just to be safe.
542 */
543 if (dm_queue_merge_is_compulsory(q) && !ti->type->merge)
544 blk_limits_max_hw_sectors(limits,
545 (unsigned int) (PAGE_SIZE >> 9));
546 return 0;
547}
548EXPORT_SYMBOL_GPL(dm_set_device_limits);
549
550/*
551 * Decrement a device's use count and remove it if necessary.
552 */
553void dm_put_device(struct dm_target *ti, struct dm_dev *d)
554{
555 struct dm_dev_internal *dd = container_of(d, struct dm_dev_internal,
556 dm_dev);
557
558 if (atomic_dec_and_test(&dd->count)) {
559 close_dev(dd, ti->table->md);
560 list_del(&dd->list);
561 kfree(dd);
562 }
563}
564EXPORT_SYMBOL(dm_put_device);
565
566/*
567 * Checks to see if the target joins onto the end of the table.
568 */
569static int adjoin(struct dm_table *table, struct dm_target *ti)
570{
571 struct dm_target *prev;
572
573 if (!table->num_targets)
574 return !ti->begin;
575
576 prev = &table->targets[table->num_targets - 1];
577 return (ti->begin == (prev->begin + prev->len));
578}
579
580/*
581 * Used to dynamically allocate the arg array.
582 */
583static char **realloc_argv(unsigned *array_size, char **old_argv)
584{
585 char **argv;
586 unsigned new_size;
587
588 new_size = *array_size ? *array_size * 2 : 64;
589 argv = kmalloc(new_size * sizeof(*argv), GFP_KERNEL);
590 if (argv) {
591 memcpy(argv, old_argv, *array_size * sizeof(*argv));
592 *array_size = new_size;
593 }
594
595 kfree(old_argv);
596 return argv;
597}
598
599/*
600 * Destructively splits up the argument list to pass to ctr.
601 */
602int dm_split_args(int *argc, char ***argvp, char *input)
603{
604 char *start, *end = input, *out, **argv = NULL;
605 unsigned array_size = 0;
606
607 *argc = 0;
608
609 if (!input) {
610 *argvp = NULL;
611 return 0;
612 }
613
614 argv = realloc_argv(&array_size, argv);
615 if (!argv)
616 return -ENOMEM;
617
618 while (1) {
619 /* Skip whitespace */
620 start = skip_spaces(end);
621
622 if (!*start)
623 break; /* success, we hit the end */
624
625 /* 'out' is used to remove any back-quotes */
626 end = out = start;
627 while (*end) {
628 /* Everything apart from '\0' can be quoted */
629 if (*end == '\\' && *(end + 1)) {
630 *out++ = *(end + 1);
631 end += 2;
632 continue;
633 }
634
635 if (isspace(*end))
636 break; /* end of token */
637
638 *out++ = *end++;
639 }
640
641 /* have we already filled the array ? */
642 if ((*argc + 1) > array_size) {
643 argv = realloc_argv(&array_size, argv);
644 if (!argv)
645 return -ENOMEM;
646 }
647
648 /* we know this is whitespace */
649 if (*end)
650 end++;
651
652 /* terminate the string and put it in the array */
653 *out = '\0';
654 argv[*argc] = start;
655 (*argc)++;
656 }
657
658 *argvp = argv;
659 return 0;
660}
661
662/*
663 * Impose necessary and sufficient conditions on a devices's table such
664 * that any incoming bio which respects its logical_block_size can be
665 * processed successfully. If it falls across the boundary between
666 * two or more targets, the size of each piece it gets split into must
667 * be compatible with the logical_block_size of the target processing it.
668 */
669static int validate_hardware_logical_block_alignment(struct dm_table *table,
670 struct queue_limits *limits)
671{
672 /*
673 * This function uses arithmetic modulo the logical_block_size
674 * (in units of 512-byte sectors).
675 */
676 unsigned short device_logical_block_size_sects =
677 limits->logical_block_size >> SECTOR_SHIFT;
678
679 /*
680 * Offset of the start of the next table entry, mod logical_block_size.
681 */
682 unsigned short next_target_start = 0;
683
684 /*
685 * Given an aligned bio that extends beyond the end of a
686 * target, how many sectors must the next target handle?
687 */
688 unsigned short remaining = 0;
689
690 struct dm_target *uninitialized_var(ti);
691 struct queue_limits ti_limits;
692 unsigned i = 0;
693
694 /*
695 * Check each entry in the table in turn.
696 */
697 while (i < dm_table_get_num_targets(table)) {
698 ti = dm_table_get_target(table, i++);
699
700 blk_set_default_limits(&ti_limits);
701
702 /* combine all target devices' limits */
703 if (ti->type->iterate_devices)
704 ti->type->iterate_devices(ti, dm_set_device_limits,
705 &ti_limits);
706
707 /*
708 * If the remaining sectors fall entirely within this
709 * table entry are they compatible with its logical_block_size?
710 */
711 if (remaining < ti->len &&
712 remaining & ((ti_limits.logical_block_size >>
713 SECTOR_SHIFT) - 1))
714 break; /* Error */
715
716 next_target_start =
717 (unsigned short) ((next_target_start + ti->len) &
718 (device_logical_block_size_sects - 1));
719 remaining = next_target_start ?
720 device_logical_block_size_sects - next_target_start : 0;
721 }
722
723 if (remaining) {
724 DMWARN("%s: table line %u (start sect %llu len %llu) "
725 "not aligned to h/w logical block size %u",
726 dm_device_name(table->md), i,
727 (unsigned long long) ti->begin,
728 (unsigned long long) ti->len,
729 limits->logical_block_size);
730 return -EINVAL;
731 }
732
733 return 0;
734}
735
736int dm_table_add_target(struct dm_table *t, const char *type,
737 sector_t start, sector_t len, char *params)
738{
739 int r = -EINVAL, argc;
740 char **argv;
741 struct dm_target *tgt;
742
743 if ((r = check_space(t)))
744 return r;
745
746 tgt = t->targets + t->num_targets;
747 memset(tgt, 0, sizeof(*tgt));
748
749 if (!len) {
750 DMERR("%s: zero-length target", dm_device_name(t->md));
751 return -EINVAL;
752 }
753
754 tgt->type = dm_get_target_type(type);
755 if (!tgt->type) {
756 DMERR("%s: %s: unknown target type", dm_device_name(t->md),
757 type);
758 return -EINVAL;
759 }
760
761 tgt->table = t;
762 tgt->begin = start;
763 tgt->len = len;
764 tgt->error = "Unknown error";
765
766 /*
767 * Does this target adjoin the previous one ?
768 */
769 if (!adjoin(t, tgt)) {
770 tgt->error = "Gap in table";
771 r = -EINVAL;
772 goto bad;
773 }
774
775 r = dm_split_args(&argc, &argv, params);
776 if (r) {
777 tgt->error = "couldn't split parameters (insufficient memory)";
778 goto bad;
779 }
780
781 r = tgt->type->ctr(tgt, argc, argv);
782 kfree(argv);
783 if (r)
784 goto bad;
785
786 t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
787
788 if (!tgt->num_discard_requests && tgt->discards_supported)
789 DMWARN("%s: %s: ignoring discards_supported because num_discard_requests is zero.",
790 dm_device_name(t->md), type);
791
792 return 0;
793
794 bad:
795 DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
796 dm_put_target_type(tgt->type);
797 return r;
798}
799
800/*
801 * Target argument parsing helpers.
802 */
803static int validate_next_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
804 unsigned *value, char **error, unsigned grouped)
805{
806 const char *arg_str = dm_shift_arg(arg_set);
807
808 if (!arg_str ||
809 (sscanf(arg_str, "%u", value) != 1) ||
810 (*value < arg->min) ||
811 (*value > arg->max) ||
812 (grouped && arg_set->argc < *value)) {
813 *error = arg->error;
814 return -EINVAL;
815 }
816
817 return 0;
818}
819
820int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
821 unsigned *value, char **error)
822{
823 return validate_next_arg(arg, arg_set, value, error, 0);
824}
825EXPORT_SYMBOL(dm_read_arg);
826
827int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set,
828 unsigned *value, char **error)
829{
830 return validate_next_arg(arg, arg_set, value, error, 1);
831}
832EXPORT_SYMBOL(dm_read_arg_group);
833
834const char *dm_shift_arg(struct dm_arg_set *as)
835{
836 char *r;
837
838 if (as->argc) {
839 as->argc--;
840 r = *as->argv;
841 as->argv++;
842 return r;
843 }
844
845 return NULL;
846}
847EXPORT_SYMBOL(dm_shift_arg);
848
849void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
850{
851 BUG_ON(as->argc < num_args);
852 as->argc -= num_args;
853 as->argv += num_args;
854}
855EXPORT_SYMBOL(dm_consume_args);
856
857static int dm_table_set_type(struct dm_table *t)
858{
859 unsigned i;
860 unsigned bio_based = 0, request_based = 0;
861 struct dm_target *tgt;
862 struct dm_dev_internal *dd;
863 struct list_head *devices;
864
865 for (i = 0; i < t->num_targets; i++) {
866 tgt = t->targets + i;
867 if (dm_target_request_based(tgt))
868 request_based = 1;
869 else
870 bio_based = 1;
871
872 if (bio_based && request_based) {
873 DMWARN("Inconsistent table: different target types"
874 " can't be mixed up");
875 return -EINVAL;
876 }
877 }
878
879 if (bio_based) {
880 /* We must use this table as bio-based */
881 t->type = DM_TYPE_BIO_BASED;
882 return 0;
883 }
884
885 BUG_ON(!request_based); /* No targets in this table */
886
887 /* Non-request-stackable devices can't be used for request-based dm */
888 devices = dm_table_get_devices(t);
889 list_for_each_entry(dd, devices, list) {
890 if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev.bdev))) {
891 DMWARN("table load rejected: including"
892 " non-request-stackable devices");
893 return -EINVAL;
894 }
895 }
896
897 /*
898 * Request-based dm supports only tables that have a single target now.
899 * To support multiple targets, request splitting support is needed,
900 * and that needs lots of changes in the block-layer.
901 * (e.g. request completion process for partial completion.)
902 */
903 if (t->num_targets > 1) {
904 DMWARN("Request-based dm doesn't support multiple targets yet");
905 return -EINVAL;
906 }
907
908 t->type = DM_TYPE_REQUEST_BASED;
909
910 return 0;
911}
912
913unsigned dm_table_get_type(struct dm_table *t)
914{
915 return t->type;
916}
917
918bool dm_table_request_based(struct dm_table *t)
919{
920 return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED;
921}
922
923int dm_table_alloc_md_mempools(struct dm_table *t)
924{
925 unsigned type = dm_table_get_type(t);
926
927 if (unlikely(type == DM_TYPE_NONE)) {
928 DMWARN("no table type is set, can't allocate mempools");
929 return -EINVAL;
930 }
931
932 t->mempools = dm_alloc_md_mempools(type, t->integrity_supported);
933 if (!t->mempools)
934 return -ENOMEM;
935
936 return 0;
937}
938
939void dm_table_free_md_mempools(struct dm_table *t)
940{
941 dm_free_md_mempools(t->mempools);
942 t->mempools = NULL;
943}
944
945struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
946{
947 return t->mempools;
948}
949
950static int setup_indexes(struct dm_table *t)
951{
952 int i;
953 unsigned int total = 0;
954 sector_t *indexes;
955
956 /* allocate the space for *all* the indexes */
957 for (i = t->depth - 2; i >= 0; i--) {
958 t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
959 total += t->counts[i];
960 }
961
962 indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE);
963 if (!indexes)
964 return -ENOMEM;
965
966 /* set up internal nodes, bottom-up */
967 for (i = t->depth - 2; i >= 0; i--) {
968 t->index[i] = indexes;
969 indexes += (KEYS_PER_NODE * t->counts[i]);
970 setup_btree_index(i, t);
971 }
972
973 return 0;
974}
975
976/*
977 * Builds the btree to index the map.
978 */
979static int dm_table_build_index(struct dm_table *t)
980{
981 int r = 0;
982 unsigned int leaf_nodes;
983
984 /* how many indexes will the btree have ? */
985 leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
986 t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
987
988 /* leaf layer has already been set up */
989 t->counts[t->depth - 1] = leaf_nodes;
990 t->index[t->depth - 1] = t->highs;
991
992 if (t->depth >= 2)
993 r = setup_indexes(t);
994
995 return r;
996}
997
998/*
999 * Get a disk whose integrity profile reflects the table's profile.
1000 * If %match_all is true, all devices' profiles must match.
1001 * If %match_all is false, all devices must at least have an
1002 * allocated integrity profile; but uninitialized is ok.
1003 * Returns NULL if integrity support was inconsistent or unavailable.
1004 */
1005static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t,
1006 bool match_all)
1007{
1008 struct list_head *devices = dm_table_get_devices(t);
1009 struct dm_dev_internal *dd = NULL;
1010 struct gendisk *prev_disk = NULL, *template_disk = NULL;
1011
1012 list_for_each_entry(dd, devices, list) {
1013 template_disk = dd->dm_dev.bdev->bd_disk;
1014 if (!blk_get_integrity(template_disk))
1015 goto no_integrity;
1016 if (!match_all && !blk_integrity_is_initialized(template_disk))
1017 continue; /* skip uninitialized profiles */
1018 else if (prev_disk &&
1019 blk_integrity_compare(prev_disk, template_disk) < 0)
1020 goto no_integrity;
1021 prev_disk = template_disk;
1022 }
1023
1024 return template_disk;
1025
1026no_integrity:
1027 if (prev_disk)
1028 DMWARN("%s: integrity not set: %s and %s profile mismatch",
1029 dm_device_name(t->md),
1030 prev_disk->disk_name,
1031 template_disk->disk_name);
1032 return NULL;
1033}
1034
1035/*
1036 * Register the mapped device for blk_integrity support if
1037 * the underlying devices have an integrity profile. But all devices
1038 * may not have matching profiles (checking all devices isn't reliable
1039 * during table load because this table may use other DM device(s) which
1040 * must be resumed before they will have an initialized integity profile).
1041 * Stacked DM devices force a 2 stage integrity profile validation:
1042 * 1 - during load, validate all initialized integrity profiles match
1043 * 2 - during resume, validate all integrity profiles match
1044 */
1045static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md)
1046{
1047 struct gendisk *template_disk = NULL;
1048
1049 template_disk = dm_table_get_integrity_disk(t, false);
1050 if (!template_disk)
1051 return 0;
1052
1053 if (!blk_integrity_is_initialized(dm_disk(md))) {
1054 t->integrity_supported = 1;
1055 return blk_integrity_register(dm_disk(md), NULL);
1056 }
1057
1058 /*
1059 * If DM device already has an initalized integrity
1060 * profile the new profile should not conflict.
1061 */
1062 if (blk_integrity_is_initialized(template_disk) &&
1063 blk_integrity_compare(dm_disk(md), template_disk) < 0) {
1064 DMWARN("%s: conflict with existing integrity profile: "
1065 "%s profile mismatch",
1066 dm_device_name(t->md),
1067 template_disk->disk_name);
1068 return 1;
1069 }
1070
1071 /* Preserve existing initialized integrity profile */
1072 t->integrity_supported = 1;
1073 return 0;
1074}
1075
1076/*
1077 * Prepares the table for use by building the indices,
1078 * setting the type, and allocating mempools.
1079 */
1080int dm_table_complete(struct dm_table *t)
1081{
1082 int r;
1083
1084 r = dm_table_set_type(t);
1085 if (r) {
1086 DMERR("unable to set table type");
1087 return r;
1088 }
1089
1090 r = dm_table_build_index(t);
1091 if (r) {
1092 DMERR("unable to build btrees");
1093 return r;
1094 }
1095
1096 r = dm_table_prealloc_integrity(t, t->md);
1097 if (r) {
1098 DMERR("could not register integrity profile.");
1099 return r;
1100 }
1101
1102 r = dm_table_alloc_md_mempools(t);
1103 if (r)
1104 DMERR("unable to allocate mempools");
1105
1106 return r;
1107}
1108
1109static DEFINE_MUTEX(_event_lock);
1110void dm_table_event_callback(struct dm_table *t,
1111 void (*fn)(void *), void *context)
1112{
1113 mutex_lock(&_event_lock);
1114 t->event_fn = fn;
1115 t->event_context = context;
1116 mutex_unlock(&_event_lock);
1117}
1118
1119void dm_table_event(struct dm_table *t)
1120{
1121 /*
1122 * You can no longer call dm_table_event() from interrupt
1123 * context, use a bottom half instead.
1124 */
1125 BUG_ON(in_interrupt());
1126
1127 mutex_lock(&_event_lock);
1128 if (t->event_fn)
1129 t->event_fn(t->event_context);
1130 mutex_unlock(&_event_lock);
1131}
1132EXPORT_SYMBOL(dm_table_event);
1133
1134sector_t dm_table_get_size(struct dm_table *t)
1135{
1136 return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
1137}
1138EXPORT_SYMBOL(dm_table_get_size);
1139
1140struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
1141{
1142 if (index >= t->num_targets)
1143 return NULL;
1144
1145 return t->targets + index;
1146}
1147
1148/*
1149 * Search the btree for the correct target.
1150 *
1151 * Caller should check returned pointer with dm_target_is_valid()
1152 * to trap I/O beyond end of device.
1153 */
1154struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
1155{
1156 unsigned int l, n = 0, k = 0;
1157 sector_t *node;
1158
1159 for (l = 0; l < t->depth; l++) {
1160 n = get_child(n, k);
1161 node = get_node(t, l, n);
1162
1163 for (k = 0; k < KEYS_PER_NODE; k++)
1164 if (node[k] >= sector)
1165 break;
1166 }
1167
1168 return &t->targets[(KEYS_PER_NODE * n) + k];
1169}
1170
1171/*
1172 * Establish the new table's queue_limits and validate them.
1173 */
1174int dm_calculate_queue_limits(struct dm_table *table,
1175 struct queue_limits *limits)
1176{
1177 struct dm_target *uninitialized_var(ti);
1178 struct queue_limits ti_limits;
1179 unsigned i = 0;
1180
1181 blk_set_default_limits(limits);
1182
1183 while (i < dm_table_get_num_targets(table)) {
1184 blk_set_default_limits(&ti_limits);
1185
1186 ti = dm_table_get_target(table, i++);
1187
1188 if (!ti->type->iterate_devices)
1189 goto combine_limits;
1190
1191 /*
1192 * Combine queue limits of all the devices this target uses.
1193 */
1194 ti->type->iterate_devices(ti, dm_set_device_limits,
1195 &ti_limits);
1196
1197 /* Set I/O hints portion of queue limits */
1198 if (ti->type->io_hints)
1199 ti->type->io_hints(ti, &ti_limits);
1200
1201 /*
1202 * Check each device area is consistent with the target's
1203 * overall queue limits.
1204 */
1205 if (ti->type->iterate_devices(ti, device_area_is_invalid,
1206 &ti_limits))
1207 return -EINVAL;
1208
1209combine_limits:
1210 /*
1211 * Merge this target's queue limits into the overall limits
1212 * for the table.
1213 */
1214 if (blk_stack_limits(limits, &ti_limits, 0) < 0)
1215 DMWARN("%s: adding target device "
1216 "(start sect %llu len %llu) "
1217 "caused an alignment inconsistency",
1218 dm_device_name(table->md),
1219 (unsigned long long) ti->begin,
1220 (unsigned long long) ti->len);
1221 }
1222
1223 return validate_hardware_logical_block_alignment(table, limits);
1224}
1225
1226/*
1227 * Set the integrity profile for this device if all devices used have
1228 * matching profiles. We're quite deep in the resume path but still
1229 * don't know if all devices (particularly DM devices this device
1230 * may be stacked on) have matching profiles. Even if the profiles
1231 * don't match we have no way to fail (to resume) at this point.
1232 */
1233static void dm_table_set_integrity(struct dm_table *t)
1234{
1235 struct gendisk *template_disk = NULL;
1236
1237 if (!blk_get_integrity(dm_disk(t->md)))
1238 return;
1239
1240 template_disk = dm_table_get_integrity_disk(t, true);
1241 if (template_disk)
1242 blk_integrity_register(dm_disk(t->md),
1243 blk_get_integrity(template_disk));
1244 else if (blk_integrity_is_initialized(dm_disk(t->md)))
1245 DMWARN("%s: device no longer has a valid integrity profile",
1246 dm_device_name(t->md));
1247 else
1248 DMWARN("%s: unable to establish an integrity profile",
1249 dm_device_name(t->md));
1250}
1251
1252static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
1253 sector_t start, sector_t len, void *data)
1254{
1255 unsigned flush = (*(unsigned *)data);
1256 struct request_queue *q = bdev_get_queue(dev->bdev);
1257
1258 return q && (q->flush_flags & flush);
1259}
1260
1261static bool dm_table_supports_flush(struct dm_table *t, unsigned flush)
1262{
1263 struct dm_target *ti;
1264 unsigned i = 0;
1265
1266 /*
1267 * Require at least one underlying device to support flushes.
1268 * t->devices includes internal dm devices such as mirror logs
1269 * so we need to use iterate_devices here, which targets
1270 * supporting flushes must provide.
1271 */
1272 while (i < dm_table_get_num_targets(t)) {
1273 ti = dm_table_get_target(t, i++);
1274
1275 if (!ti->num_flush_requests)
1276 continue;
1277
1278 if (ti->type->iterate_devices &&
1279 ti->type->iterate_devices(ti, device_flush_capable, &flush))
1280 return 1;
1281 }
1282
1283 return 0;
1284}
1285
1286static bool dm_table_discard_zeroes_data(struct dm_table *t)
1287{
1288 struct dm_target *ti;
1289 unsigned i = 0;
1290
1291 /* Ensure that all targets supports discard_zeroes_data. */
1292 while (i < dm_table_get_num_targets(t)) {
1293 ti = dm_table_get_target(t, i++);
1294
1295 if (ti->discard_zeroes_data_unsupported)
1296 return 0;
1297 }
1298
1299 return 1;
1300}
1301
1302void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1303 struct queue_limits *limits)
1304{
1305 unsigned flush = 0;
1306
1307 /*
1308 * Copy table's limits to the DM device's request_queue
1309 */
1310 q->limits = *limits;
1311
1312 if (!dm_table_supports_discards(t))
1313 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
1314 else
1315 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
1316
1317 if (dm_table_supports_flush(t, REQ_FLUSH)) {
1318 flush |= REQ_FLUSH;
1319 if (dm_table_supports_flush(t, REQ_FUA))
1320 flush |= REQ_FUA;
1321 }
1322 blk_queue_flush(q, flush);
1323
1324 if (!dm_table_discard_zeroes_data(t))
1325 q->limits.discard_zeroes_data = 0;
1326
1327 dm_table_set_integrity(t);
1328
1329 /*
1330 * QUEUE_FLAG_STACKABLE must be set after all queue settings are
1331 * visible to other CPUs because, once the flag is set, incoming bios
1332 * are processed by request-based dm, which refers to the queue
1333 * settings.
1334 * Until the flag set, bios are passed to bio-based dm and queued to
1335 * md->deferred where queue settings are not needed yet.
1336 * Those bios are passed to request-based dm at the resume time.
1337 */
1338 smp_mb();
1339 if (dm_table_request_based(t))
1340 queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q);
1341}
1342
1343unsigned int dm_table_get_num_targets(struct dm_table *t)
1344{
1345 return t->num_targets;
1346}
1347
1348struct list_head *dm_table_get_devices(struct dm_table *t)
1349{
1350 return &t->devices;
1351}
1352
1353fmode_t dm_table_get_mode(struct dm_table *t)
1354{
1355 return t->mode;
1356}
1357EXPORT_SYMBOL(dm_table_get_mode);
1358
1359static void suspend_targets(struct dm_table *t, unsigned postsuspend)
1360{
1361 int i = t->num_targets;
1362 struct dm_target *ti = t->targets;
1363
1364 while (i--) {
1365 if (postsuspend) {
1366 if (ti->type->postsuspend)
1367 ti->type->postsuspend(ti);
1368 } else if (ti->type->presuspend)
1369 ti->type->presuspend(ti);
1370
1371 ti++;
1372 }
1373}
1374
1375void dm_table_presuspend_targets(struct dm_table *t)
1376{
1377 if (!t)
1378 return;
1379
1380 suspend_targets(t, 0);
1381}
1382
1383void dm_table_postsuspend_targets(struct dm_table *t)
1384{
1385 if (!t)
1386 return;
1387
1388 suspend_targets(t, 1);
1389}
1390
1391int dm_table_resume_targets(struct dm_table *t)
1392{
1393 int i, r = 0;
1394
1395 for (i = 0; i < t->num_targets; i++) {
1396 struct dm_target *ti = t->targets + i;
1397
1398 if (!ti->type->preresume)
1399 continue;
1400
1401 r = ti->type->preresume(ti);
1402 if (r)
1403 return r;
1404 }
1405
1406 for (i = 0; i < t->num_targets; i++) {
1407 struct dm_target *ti = t->targets + i;
1408
1409 if (ti->type->resume)
1410 ti->type->resume(ti);
1411 }
1412
1413 return 0;
1414}
1415
1416void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb)
1417{
1418 list_add(&cb->list, &t->target_callbacks);
1419}
1420EXPORT_SYMBOL_GPL(dm_table_add_target_callbacks);
1421
1422int dm_table_any_congested(struct dm_table *t, int bdi_bits)
1423{
1424 struct dm_dev_internal *dd;
1425 struct list_head *devices = dm_table_get_devices(t);
1426 struct dm_target_callbacks *cb;
1427 int r = 0;
1428
1429 list_for_each_entry(dd, devices, list) {
1430 struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev);
1431 char b[BDEVNAME_SIZE];
1432
1433 if (likely(q))
1434 r |= bdi_congested(&q->backing_dev_info, bdi_bits);
1435 else
1436 DMWARN_LIMIT("%s: any_congested: nonexistent device %s",
1437 dm_device_name(t->md),
1438 bdevname(dd->dm_dev.bdev, b));
1439 }
1440
1441 list_for_each_entry(cb, &t->target_callbacks, list)
1442 if (cb->congested_fn)
1443 r |= cb->congested_fn(cb, bdi_bits);
1444
1445 return r;
1446}
1447
1448int dm_table_any_busy_target(struct dm_table *t)
1449{
1450 unsigned i;
1451 struct dm_target *ti;
1452
1453 for (i = 0; i < t->num_targets; i++) {
1454 ti = t->targets + i;
1455 if (ti->type->busy && ti->type->busy(ti))
1456 return 1;
1457 }
1458
1459 return 0;
1460}
1461
1462struct mapped_device *dm_table_get_md(struct dm_table *t)
1463{
1464 return t->md;
1465}
1466EXPORT_SYMBOL(dm_table_get_md);
1467
1468static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev,
1469 sector_t start, sector_t len, void *data)
1470{
1471 struct request_queue *q = bdev_get_queue(dev->bdev);
1472
1473 return q && blk_queue_discard(q);
1474}
1475
1476bool dm_table_supports_discards(struct dm_table *t)
1477{
1478 struct dm_target *ti;
1479 unsigned i = 0;
1480
1481 /*
1482 * Unless any target used by the table set discards_supported,
1483 * require at least one underlying device to support discards.
1484 * t->devices includes internal dm devices such as mirror logs
1485 * so we need to use iterate_devices here, which targets
1486 * supporting discard selectively must provide.
1487 */
1488 while (i < dm_table_get_num_targets(t)) {
1489 ti = dm_table_get_target(t, i++);
1490
1491 if (!ti->num_discard_requests)
1492 continue;
1493
1494 if (ti->discards_supported)
1495 return 1;
1496
1497 if (ti->type->iterate_devices &&
1498 ti->type->iterate_devices(ti, device_discard_capable, NULL))
1499 return 1;
1500 }
1501
1502 return 0;
1503}
1/*
2 * Copyright (C) 2001 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
11#include <linux/module.h>
12#include <linux/vmalloc.h>
13#include <linux/blkdev.h>
14#include <linux/blk-integrity.h>
15#include <linux/namei.h>
16#include <linux/ctype.h>
17#include <linux/string.h>
18#include <linux/slab.h>
19#include <linux/interrupt.h>
20#include <linux/mutex.h>
21#include <linux/delay.h>
22#include <linux/atomic.h>
23#include <linux/blk-mq.h>
24#include <linux/mount.h>
25#include <linux/dax.h>
26
27#define DM_MSG_PREFIX "table"
28
29#define NODE_SIZE L1_CACHE_BYTES
30#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
31#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
32
33/*
34 * Similar to ceiling(log_size(n))
35 */
36static unsigned int int_log(unsigned int n, unsigned int base)
37{
38 int result = 0;
39
40 while (n > 1) {
41 n = dm_div_up(n, base);
42 result++;
43 }
44
45 return result;
46}
47
48/*
49 * Calculate the index of the child node of the n'th node k'th key.
50 */
51static inline unsigned int get_child(unsigned int n, unsigned int k)
52{
53 return (n * CHILDREN_PER_NODE) + k;
54}
55
56/*
57 * Return the n'th node of level l from table t.
58 */
59static inline sector_t *get_node(struct dm_table *t,
60 unsigned int l, unsigned int n)
61{
62 return t->index[l] + (n * KEYS_PER_NODE);
63}
64
65/*
66 * Return the highest key that you could lookup from the n'th
67 * node on level l of the btree.
68 */
69static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
70{
71 for (; l < t->depth - 1; l++)
72 n = get_child(n, CHILDREN_PER_NODE - 1);
73
74 if (n >= t->counts[l])
75 return (sector_t) - 1;
76
77 return get_node(t, l, n)[KEYS_PER_NODE - 1];
78}
79
80/*
81 * Fills in a level of the btree based on the highs of the level
82 * below it.
83 */
84static int setup_btree_index(unsigned int l, struct dm_table *t)
85{
86 unsigned int n, k;
87 sector_t *node;
88
89 for (n = 0U; n < t->counts[l]; n++) {
90 node = get_node(t, l, n);
91
92 for (k = 0U; k < KEYS_PER_NODE; k++)
93 node[k] = high(t, l + 1, get_child(n, k));
94 }
95
96 return 0;
97}
98
99/*
100 * highs, and targets are managed as dynamic arrays during a
101 * table load.
102 */
103static int alloc_targets(struct dm_table *t, unsigned int num)
104{
105 sector_t *n_highs;
106 struct dm_target *n_targets;
107
108 /*
109 * Allocate both the target array and offset array at once.
110 */
111 n_highs = kvcalloc(num, sizeof(struct dm_target) + sizeof(sector_t),
112 GFP_KERNEL);
113 if (!n_highs)
114 return -ENOMEM;
115
116 n_targets = (struct dm_target *) (n_highs + num);
117
118 memset(n_highs, -1, sizeof(*n_highs) * num);
119 kvfree(t->highs);
120
121 t->num_allocated = num;
122 t->highs = n_highs;
123 t->targets = n_targets;
124
125 return 0;
126}
127
128int dm_table_create(struct dm_table **result, fmode_t mode,
129 unsigned num_targets, struct mapped_device *md)
130{
131 struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
132
133 if (!t)
134 return -ENOMEM;
135
136 INIT_LIST_HEAD(&t->devices);
137
138 if (!num_targets)
139 num_targets = KEYS_PER_NODE;
140
141 num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
142
143 if (!num_targets) {
144 kfree(t);
145 return -ENOMEM;
146 }
147
148 if (alloc_targets(t, num_targets)) {
149 kfree(t);
150 return -ENOMEM;
151 }
152
153 t->type = DM_TYPE_NONE;
154 t->mode = mode;
155 t->md = md;
156 *result = t;
157 return 0;
158}
159
160static void free_devices(struct list_head *devices, struct mapped_device *md)
161{
162 struct list_head *tmp, *next;
163
164 list_for_each_safe(tmp, next, devices) {
165 struct dm_dev_internal *dd =
166 list_entry(tmp, struct dm_dev_internal, list);
167 DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
168 dm_device_name(md), dd->dm_dev->name);
169 dm_put_table_device(md, dd->dm_dev);
170 kfree(dd);
171 }
172}
173
174static void dm_table_destroy_crypto_profile(struct dm_table *t);
175
176void dm_table_destroy(struct dm_table *t)
177{
178 if (!t)
179 return;
180
181 /* free the indexes */
182 if (t->depth >= 2)
183 kvfree(t->index[t->depth - 2]);
184
185 /* free the targets */
186 for (unsigned int i = 0; i < t->num_targets; i++) {
187 struct dm_target *ti = dm_table_get_target(t, i);
188
189 if (ti->type->dtr)
190 ti->type->dtr(ti);
191
192 dm_put_target_type(ti->type);
193 }
194
195 kvfree(t->highs);
196
197 /* free the device list */
198 free_devices(&t->devices, t->md);
199
200 dm_free_md_mempools(t->mempools);
201
202 dm_table_destroy_crypto_profile(t);
203
204 kfree(t);
205}
206
207/*
208 * See if we've already got a device in the list.
209 */
210static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
211{
212 struct dm_dev_internal *dd;
213
214 list_for_each_entry (dd, l, list)
215 if (dd->dm_dev->bdev->bd_dev == dev)
216 return dd;
217
218 return NULL;
219}
220
221/*
222 * If possible, this checks an area of a destination device is invalid.
223 */
224static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
225 sector_t start, sector_t len, void *data)
226{
227 struct queue_limits *limits = data;
228 struct block_device *bdev = dev->bdev;
229 sector_t dev_size = bdev_nr_sectors(bdev);
230 unsigned short logical_block_size_sectors =
231 limits->logical_block_size >> SECTOR_SHIFT;
232
233 if (!dev_size)
234 return 0;
235
236 if ((start >= dev_size) || (start + len > dev_size)) {
237 DMERR("%s: %pg too small for target: "
238 "start=%llu, len=%llu, dev_size=%llu",
239 dm_device_name(ti->table->md), bdev,
240 (unsigned long long)start,
241 (unsigned long long)len,
242 (unsigned long long)dev_size);
243 return 1;
244 }
245
246 /*
247 * If the target is mapped to zoned block device(s), check
248 * that the zones are not partially mapped.
249 */
250 if (bdev_is_zoned(bdev)) {
251 unsigned int zone_sectors = bdev_zone_sectors(bdev);
252
253 if (start & (zone_sectors - 1)) {
254 DMERR("%s: start=%llu not aligned to h/w zone size %u of %pg",
255 dm_device_name(ti->table->md),
256 (unsigned long long)start,
257 zone_sectors, bdev);
258 return 1;
259 }
260
261 /*
262 * Note: The last zone of a zoned block device may be smaller
263 * than other zones. So for a target mapping the end of a
264 * zoned block device with such a zone, len would not be zone
265 * aligned. We do not allow such last smaller zone to be part
266 * of the mapping here to ensure that mappings with multiple
267 * devices do not end up with a smaller zone in the middle of
268 * the sector range.
269 */
270 if (len & (zone_sectors - 1)) {
271 DMERR("%s: len=%llu not aligned to h/w zone size %u of %pg",
272 dm_device_name(ti->table->md),
273 (unsigned long long)len,
274 zone_sectors, bdev);
275 return 1;
276 }
277 }
278
279 if (logical_block_size_sectors <= 1)
280 return 0;
281
282 if (start & (logical_block_size_sectors - 1)) {
283 DMERR("%s: start=%llu not aligned to h/w "
284 "logical block size %u of %pg",
285 dm_device_name(ti->table->md),
286 (unsigned long long)start,
287 limits->logical_block_size, bdev);
288 return 1;
289 }
290
291 if (len & (logical_block_size_sectors - 1)) {
292 DMERR("%s: len=%llu not aligned to h/w "
293 "logical block size %u of %pg",
294 dm_device_name(ti->table->md),
295 (unsigned long long)len,
296 limits->logical_block_size, bdev);
297 return 1;
298 }
299
300 return 0;
301}
302
303/*
304 * This upgrades the mode on an already open dm_dev, being
305 * careful to leave things as they were if we fail to reopen the
306 * device and not to touch the existing bdev field in case
307 * it is accessed concurrently.
308 */
309static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
310 struct mapped_device *md)
311{
312 int r;
313 struct dm_dev *old_dev, *new_dev;
314
315 old_dev = dd->dm_dev;
316
317 r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
318 dd->dm_dev->mode | new_mode, &new_dev);
319 if (r)
320 return r;
321
322 dd->dm_dev = new_dev;
323 dm_put_table_device(md, old_dev);
324
325 return 0;
326}
327
328/*
329 * Convert the path to a device
330 */
331dev_t dm_get_dev_t(const char *path)
332{
333 dev_t dev;
334
335 if (lookup_bdev(path, &dev))
336 dev = name_to_dev_t(path);
337 return dev;
338}
339EXPORT_SYMBOL_GPL(dm_get_dev_t);
340
341/*
342 * Add a device to the list, or just increment the usage count if
343 * it's already present.
344 */
345int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
346 struct dm_dev **result)
347{
348 int r;
349 dev_t dev;
350 unsigned int major, minor;
351 char dummy;
352 struct dm_dev_internal *dd;
353 struct dm_table *t = ti->table;
354
355 BUG_ON(!t);
356
357 if (sscanf(path, "%u:%u%c", &major, &minor, &dummy) == 2) {
358 /* Extract the major/minor numbers */
359 dev = MKDEV(major, minor);
360 if (MAJOR(dev) != major || MINOR(dev) != minor)
361 return -EOVERFLOW;
362 } else {
363 dev = dm_get_dev_t(path);
364 if (!dev)
365 return -ENODEV;
366 }
367
368 dd = find_device(&t->devices, dev);
369 if (!dd) {
370 dd = kmalloc(sizeof(*dd), GFP_KERNEL);
371 if (!dd)
372 return -ENOMEM;
373
374 if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) {
375 kfree(dd);
376 return r;
377 }
378
379 refcount_set(&dd->count, 1);
380 list_add(&dd->list, &t->devices);
381 goto out;
382
383 } else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
384 r = upgrade_mode(dd, mode, t->md);
385 if (r)
386 return r;
387 }
388 refcount_inc(&dd->count);
389out:
390 *result = dd->dm_dev;
391 return 0;
392}
393EXPORT_SYMBOL(dm_get_device);
394
395static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
396 sector_t start, sector_t len, void *data)
397{
398 struct queue_limits *limits = data;
399 struct block_device *bdev = dev->bdev;
400 struct request_queue *q = bdev_get_queue(bdev);
401
402 if (unlikely(!q)) {
403 DMWARN("%s: Cannot set limits for nonexistent device %pg",
404 dm_device_name(ti->table->md), bdev);
405 return 0;
406 }
407
408 if (blk_stack_limits(limits, &q->limits,
409 get_start_sect(bdev) + start) < 0)
410 DMWARN("%s: adding target device %pg caused an alignment inconsistency: "
411 "physical_block_size=%u, logical_block_size=%u, "
412 "alignment_offset=%u, start=%llu",
413 dm_device_name(ti->table->md), bdev,
414 q->limits.physical_block_size,
415 q->limits.logical_block_size,
416 q->limits.alignment_offset,
417 (unsigned long long) start << SECTOR_SHIFT);
418 return 0;
419}
420
421/*
422 * Decrement a device's use count and remove it if necessary.
423 */
424void dm_put_device(struct dm_target *ti, struct dm_dev *d)
425{
426 int found = 0;
427 struct list_head *devices = &ti->table->devices;
428 struct dm_dev_internal *dd;
429
430 list_for_each_entry(dd, devices, list) {
431 if (dd->dm_dev == d) {
432 found = 1;
433 break;
434 }
435 }
436 if (!found) {
437 DMERR("%s: device %s not in table devices list",
438 dm_device_name(ti->table->md), d->name);
439 return;
440 }
441 if (refcount_dec_and_test(&dd->count)) {
442 dm_put_table_device(ti->table->md, d);
443 list_del(&dd->list);
444 kfree(dd);
445 }
446}
447EXPORT_SYMBOL(dm_put_device);
448
449/*
450 * Checks to see if the target joins onto the end of the table.
451 */
452static int adjoin(struct dm_table *t, struct dm_target *ti)
453{
454 struct dm_target *prev;
455
456 if (!t->num_targets)
457 return !ti->begin;
458
459 prev = &t->targets[t->num_targets - 1];
460 return (ti->begin == (prev->begin + prev->len));
461}
462
463/*
464 * Used to dynamically allocate the arg array.
465 *
466 * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
467 * process messages even if some device is suspended. These messages have a
468 * small fixed number of arguments.
469 *
470 * On the other hand, dm-switch needs to process bulk data using messages and
471 * excessive use of GFP_NOIO could cause trouble.
472 */
473static char **realloc_argv(unsigned *size, char **old_argv)
474{
475 char **argv;
476 unsigned new_size;
477 gfp_t gfp;
478
479 if (*size) {
480 new_size = *size * 2;
481 gfp = GFP_KERNEL;
482 } else {
483 new_size = 8;
484 gfp = GFP_NOIO;
485 }
486 argv = kmalloc_array(new_size, sizeof(*argv), gfp);
487 if (argv && old_argv) {
488 memcpy(argv, old_argv, *size * sizeof(*argv));
489 *size = new_size;
490 }
491
492 kfree(old_argv);
493 return argv;
494}
495
496/*
497 * Destructively splits up the argument list to pass to ctr.
498 */
499int dm_split_args(int *argc, char ***argvp, char *input)
500{
501 char *start, *end = input, *out, **argv = NULL;
502 unsigned array_size = 0;
503
504 *argc = 0;
505
506 if (!input) {
507 *argvp = NULL;
508 return 0;
509 }
510
511 argv = realloc_argv(&array_size, argv);
512 if (!argv)
513 return -ENOMEM;
514
515 while (1) {
516 /* Skip whitespace */
517 start = skip_spaces(end);
518
519 if (!*start)
520 break; /* success, we hit the end */
521
522 /* 'out' is used to remove any back-quotes */
523 end = out = start;
524 while (*end) {
525 /* Everything apart from '\0' can be quoted */
526 if (*end == '\\' && *(end + 1)) {
527 *out++ = *(end + 1);
528 end += 2;
529 continue;
530 }
531
532 if (isspace(*end))
533 break; /* end of token */
534
535 *out++ = *end++;
536 }
537
538 /* have we already filled the array ? */
539 if ((*argc + 1) > array_size) {
540 argv = realloc_argv(&array_size, argv);
541 if (!argv)
542 return -ENOMEM;
543 }
544
545 /* we know this is whitespace */
546 if (*end)
547 end++;
548
549 /* terminate the string and put it in the array */
550 *out = '\0';
551 argv[*argc] = start;
552 (*argc)++;
553 }
554
555 *argvp = argv;
556 return 0;
557}
558
559/*
560 * Impose necessary and sufficient conditions on a devices's table such
561 * that any incoming bio which respects its logical_block_size can be
562 * processed successfully. If it falls across the boundary between
563 * two or more targets, the size of each piece it gets split into must
564 * be compatible with the logical_block_size of the target processing it.
565 */
566static int validate_hardware_logical_block_alignment(struct dm_table *t,
567 struct queue_limits *limits)
568{
569 /*
570 * This function uses arithmetic modulo the logical_block_size
571 * (in units of 512-byte sectors).
572 */
573 unsigned short device_logical_block_size_sects =
574 limits->logical_block_size >> SECTOR_SHIFT;
575
576 /*
577 * Offset of the start of the next table entry, mod logical_block_size.
578 */
579 unsigned short next_target_start = 0;
580
581 /*
582 * Given an aligned bio that extends beyond the end of a
583 * target, how many sectors must the next target handle?
584 */
585 unsigned short remaining = 0;
586
587 struct dm_target *ti;
588 struct queue_limits ti_limits;
589 unsigned int i;
590
591 /*
592 * Check each entry in the table in turn.
593 */
594 for (i = 0; i < t->num_targets; i++) {
595 ti = dm_table_get_target(t, i);
596
597 blk_set_stacking_limits(&ti_limits);
598
599 /* combine all target devices' limits */
600 if (ti->type->iterate_devices)
601 ti->type->iterate_devices(ti, dm_set_device_limits,
602 &ti_limits);
603
604 /*
605 * If the remaining sectors fall entirely within this
606 * table entry are they compatible with its logical_block_size?
607 */
608 if (remaining < ti->len &&
609 remaining & ((ti_limits.logical_block_size >>
610 SECTOR_SHIFT) - 1))
611 break; /* Error */
612
613 next_target_start =
614 (unsigned short) ((next_target_start + ti->len) &
615 (device_logical_block_size_sects - 1));
616 remaining = next_target_start ?
617 device_logical_block_size_sects - next_target_start : 0;
618 }
619
620 if (remaining) {
621 DMERR("%s: table line %u (start sect %llu len %llu) "
622 "not aligned to h/w logical block size %u",
623 dm_device_name(t->md), i,
624 (unsigned long long) ti->begin,
625 (unsigned long long) ti->len,
626 limits->logical_block_size);
627 return -EINVAL;
628 }
629
630 return 0;
631}
632
633int dm_table_add_target(struct dm_table *t, const char *type,
634 sector_t start, sector_t len, char *params)
635{
636 int r = -EINVAL, argc;
637 char **argv;
638 struct dm_target *ti;
639
640 if (t->singleton) {
641 DMERR("%s: target type %s must appear alone in table",
642 dm_device_name(t->md), t->targets->type->name);
643 return -EINVAL;
644 }
645
646 BUG_ON(t->num_targets >= t->num_allocated);
647
648 ti = t->targets + t->num_targets;
649 memset(ti, 0, sizeof(*ti));
650
651 if (!len) {
652 DMERR("%s: zero-length target", dm_device_name(t->md));
653 return -EINVAL;
654 }
655
656 ti->type = dm_get_target_type(type);
657 if (!ti->type) {
658 DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
659 return -EINVAL;
660 }
661
662 if (dm_target_needs_singleton(ti->type)) {
663 if (t->num_targets) {
664 ti->error = "singleton target type must appear alone in table";
665 goto bad;
666 }
667 t->singleton = true;
668 }
669
670 if (dm_target_always_writeable(ti->type) && !(t->mode & FMODE_WRITE)) {
671 ti->error = "target type may not be included in a read-only table";
672 goto bad;
673 }
674
675 if (t->immutable_target_type) {
676 if (t->immutable_target_type != ti->type) {
677 ti->error = "immutable target type cannot be mixed with other target types";
678 goto bad;
679 }
680 } else if (dm_target_is_immutable(ti->type)) {
681 if (t->num_targets) {
682 ti->error = "immutable target type cannot be mixed with other target types";
683 goto bad;
684 }
685 t->immutable_target_type = ti->type;
686 }
687
688 if (dm_target_has_integrity(ti->type))
689 t->integrity_added = 1;
690
691 ti->table = t;
692 ti->begin = start;
693 ti->len = len;
694 ti->error = "Unknown error";
695
696 /*
697 * Does this target adjoin the previous one ?
698 */
699 if (!adjoin(t, ti)) {
700 ti->error = "Gap in table";
701 goto bad;
702 }
703
704 r = dm_split_args(&argc, &argv, params);
705 if (r) {
706 ti->error = "couldn't split parameters";
707 goto bad;
708 }
709
710 r = ti->type->ctr(ti, argc, argv);
711 kfree(argv);
712 if (r)
713 goto bad;
714
715 t->highs[t->num_targets++] = ti->begin + ti->len - 1;
716
717 if (!ti->num_discard_bios && ti->discards_supported)
718 DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
719 dm_device_name(t->md), type);
720
721 if (ti->limit_swap_bios && !static_key_enabled(&swap_bios_enabled.key))
722 static_branch_enable(&swap_bios_enabled);
723
724 return 0;
725
726 bad:
727 DMERR("%s: %s: %s (%pe)", dm_device_name(t->md), type, ti->error, ERR_PTR(r));
728 dm_put_target_type(ti->type);
729 return r;
730}
731
732/*
733 * Target argument parsing helpers.
734 */
735static int validate_next_arg(const struct dm_arg *arg,
736 struct dm_arg_set *arg_set,
737 unsigned *value, char **error, unsigned grouped)
738{
739 const char *arg_str = dm_shift_arg(arg_set);
740 char dummy;
741
742 if (!arg_str ||
743 (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
744 (*value < arg->min) ||
745 (*value > arg->max) ||
746 (grouped && arg_set->argc < *value)) {
747 *error = arg->error;
748 return -EINVAL;
749 }
750
751 return 0;
752}
753
754int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
755 unsigned *value, char **error)
756{
757 return validate_next_arg(arg, arg_set, value, error, 0);
758}
759EXPORT_SYMBOL(dm_read_arg);
760
761int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set,
762 unsigned *value, char **error)
763{
764 return validate_next_arg(arg, arg_set, value, error, 1);
765}
766EXPORT_SYMBOL(dm_read_arg_group);
767
768const char *dm_shift_arg(struct dm_arg_set *as)
769{
770 char *r;
771
772 if (as->argc) {
773 as->argc--;
774 r = *as->argv;
775 as->argv++;
776 return r;
777 }
778
779 return NULL;
780}
781EXPORT_SYMBOL(dm_shift_arg);
782
783void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
784{
785 BUG_ON(as->argc < num_args);
786 as->argc -= num_args;
787 as->argv += num_args;
788}
789EXPORT_SYMBOL(dm_consume_args);
790
791static bool __table_type_bio_based(enum dm_queue_mode table_type)
792{
793 return (table_type == DM_TYPE_BIO_BASED ||
794 table_type == DM_TYPE_DAX_BIO_BASED);
795}
796
797static bool __table_type_request_based(enum dm_queue_mode table_type)
798{
799 return table_type == DM_TYPE_REQUEST_BASED;
800}
801
802void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
803{
804 t->type = type;
805}
806EXPORT_SYMBOL_GPL(dm_table_set_type);
807
808/* validate the dax capability of the target device span */
809static int device_not_dax_capable(struct dm_target *ti, struct dm_dev *dev,
810 sector_t start, sector_t len, void *data)
811{
812 if (dev->dax_dev)
813 return false;
814
815 DMDEBUG("%pg: error: dax unsupported by block device", dev->bdev);
816 return true;
817}
818
819/* Check devices support synchronous DAX */
820static int device_not_dax_synchronous_capable(struct dm_target *ti, struct dm_dev *dev,
821 sector_t start, sector_t len, void *data)
822{
823 return !dev->dax_dev || !dax_synchronous(dev->dax_dev);
824}
825
826static bool dm_table_supports_dax(struct dm_table *t,
827 iterate_devices_callout_fn iterate_fn)
828{
829 /* Ensure that all targets support DAX. */
830 for (unsigned int i = 0; i < t->num_targets; i++) {
831 struct dm_target *ti = dm_table_get_target(t, i);
832
833 if (!ti->type->direct_access)
834 return false;
835
836 if (!ti->type->iterate_devices ||
837 ti->type->iterate_devices(ti, iterate_fn, NULL))
838 return false;
839 }
840
841 return true;
842}
843
844static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev,
845 sector_t start, sector_t len, void *data)
846{
847 struct block_device *bdev = dev->bdev;
848 struct request_queue *q = bdev_get_queue(bdev);
849
850 /* request-based cannot stack on partitions! */
851 if (bdev_is_partition(bdev))
852 return false;
853
854 return queue_is_mq(q);
855}
856
857static int dm_table_determine_type(struct dm_table *t)
858{
859 unsigned bio_based = 0, request_based = 0, hybrid = 0;
860 struct dm_target *ti;
861 struct list_head *devices = dm_table_get_devices(t);
862 enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
863
864 if (t->type != DM_TYPE_NONE) {
865 /* target already set the table's type */
866 if (t->type == DM_TYPE_BIO_BASED) {
867 /* possibly upgrade to a variant of bio-based */
868 goto verify_bio_based;
869 }
870 BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
871 goto verify_rq_based;
872 }
873
874 for (unsigned int i = 0; i < t->num_targets; i++) {
875 ti = dm_table_get_target(t, i);
876 if (dm_target_hybrid(ti))
877 hybrid = 1;
878 else if (dm_target_request_based(ti))
879 request_based = 1;
880 else
881 bio_based = 1;
882
883 if (bio_based && request_based) {
884 DMERR("Inconsistent table: different target types"
885 " can't be mixed up");
886 return -EINVAL;
887 }
888 }
889
890 if (hybrid && !bio_based && !request_based) {
891 /*
892 * The targets can work either way.
893 * Determine the type from the live device.
894 * Default to bio-based if device is new.
895 */
896 if (__table_type_request_based(live_md_type))
897 request_based = 1;
898 else
899 bio_based = 1;
900 }
901
902 if (bio_based) {
903verify_bio_based:
904 /* We must use this table as bio-based */
905 t->type = DM_TYPE_BIO_BASED;
906 if (dm_table_supports_dax(t, device_not_dax_capable) ||
907 (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) {
908 t->type = DM_TYPE_DAX_BIO_BASED;
909 }
910 return 0;
911 }
912
913 BUG_ON(!request_based); /* No targets in this table */
914
915 t->type = DM_TYPE_REQUEST_BASED;
916
917verify_rq_based:
918 /*
919 * Request-based dm supports only tables that have a single target now.
920 * To support multiple targets, request splitting support is needed,
921 * and that needs lots of changes in the block-layer.
922 * (e.g. request completion process for partial completion.)
923 */
924 if (t->num_targets > 1) {
925 DMERR("request-based DM doesn't support multiple targets");
926 return -EINVAL;
927 }
928
929 if (list_empty(devices)) {
930 int srcu_idx;
931 struct dm_table *live_table = dm_get_live_table(t->md, &srcu_idx);
932
933 /* inherit live table's type */
934 if (live_table)
935 t->type = live_table->type;
936 dm_put_live_table(t->md, srcu_idx);
937 return 0;
938 }
939
940 ti = dm_table_get_immutable_target(t);
941 if (!ti) {
942 DMERR("table load rejected: immutable target is required");
943 return -EINVAL;
944 } else if (ti->max_io_len) {
945 DMERR("table load rejected: immutable target that splits IO is not supported");
946 return -EINVAL;
947 }
948
949 /* Non-request-stackable devices can't be used for request-based dm */
950 if (!ti->type->iterate_devices ||
951 !ti->type->iterate_devices(ti, device_is_rq_stackable, NULL)) {
952 DMERR("table load rejected: including non-request-stackable devices");
953 return -EINVAL;
954 }
955
956 return 0;
957}
958
959enum dm_queue_mode dm_table_get_type(struct dm_table *t)
960{
961 return t->type;
962}
963
964struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
965{
966 return t->immutable_target_type;
967}
968
969struct dm_target *dm_table_get_immutable_target(struct dm_table *t)
970{
971 /* Immutable target is implicitly a singleton */
972 if (t->num_targets > 1 ||
973 !dm_target_is_immutable(t->targets[0].type))
974 return NULL;
975
976 return t->targets;
977}
978
979struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
980{
981 for (unsigned int i = 0; i < t->num_targets; i++) {
982 struct dm_target *ti = dm_table_get_target(t, i);
983
984 if (dm_target_is_wildcard(ti->type))
985 return ti;
986 }
987
988 return NULL;
989}
990
991bool dm_table_bio_based(struct dm_table *t)
992{
993 return __table_type_bio_based(dm_table_get_type(t));
994}
995
996bool dm_table_request_based(struct dm_table *t)
997{
998 return __table_type_request_based(dm_table_get_type(t));
999}
1000
1001static bool dm_table_supports_poll(struct dm_table *t);
1002
1003static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
1004{
1005 enum dm_queue_mode type = dm_table_get_type(t);
1006 unsigned int per_io_data_size = 0, front_pad, io_front_pad;
1007 unsigned int min_pool_size = 0, pool_size;
1008 struct dm_md_mempools *pools;
1009
1010 if (unlikely(type == DM_TYPE_NONE)) {
1011 DMERR("no table type is set, can't allocate mempools");
1012 return -EINVAL;
1013 }
1014
1015 pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id);
1016 if (!pools)
1017 return -ENOMEM;
1018
1019 if (type == DM_TYPE_REQUEST_BASED) {
1020 pool_size = dm_get_reserved_rq_based_ios();
1021 front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
1022 goto init_bs;
1023 }
1024
1025 for (unsigned int i = 0; i < t->num_targets; i++) {
1026 struct dm_target *ti = dm_table_get_target(t, i);
1027
1028 per_io_data_size = max(per_io_data_size, ti->per_io_data_size);
1029 min_pool_size = max(min_pool_size, ti->num_flush_bios);
1030 }
1031 pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size);
1032 front_pad = roundup(per_io_data_size,
1033 __alignof__(struct dm_target_io)) + DM_TARGET_IO_BIO_OFFSET;
1034
1035 io_front_pad = roundup(per_io_data_size,
1036 __alignof__(struct dm_io)) + DM_IO_BIO_OFFSET;
1037 if (bioset_init(&pools->io_bs, pool_size, io_front_pad,
1038 dm_table_supports_poll(t) ? BIOSET_PERCPU_CACHE : 0))
1039 goto out_free_pools;
1040 if (t->integrity_supported &&
1041 bioset_integrity_create(&pools->io_bs, pool_size))
1042 goto out_free_pools;
1043init_bs:
1044 if (bioset_init(&pools->bs, pool_size, front_pad, 0))
1045 goto out_free_pools;
1046 if (t->integrity_supported &&
1047 bioset_integrity_create(&pools->bs, pool_size))
1048 goto out_free_pools;
1049
1050 t->mempools = pools;
1051 return 0;
1052
1053out_free_pools:
1054 dm_free_md_mempools(pools);
1055 return -ENOMEM;
1056}
1057
1058static int setup_indexes(struct dm_table *t)
1059{
1060 int i;
1061 unsigned int total = 0;
1062 sector_t *indexes;
1063
1064 /* allocate the space for *all* the indexes */
1065 for (i = t->depth - 2; i >= 0; i--) {
1066 t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
1067 total += t->counts[i];
1068 }
1069
1070 indexes = kvcalloc(total, NODE_SIZE, GFP_KERNEL);
1071 if (!indexes)
1072 return -ENOMEM;
1073
1074 /* set up internal nodes, bottom-up */
1075 for (i = t->depth - 2; i >= 0; i--) {
1076 t->index[i] = indexes;
1077 indexes += (KEYS_PER_NODE * t->counts[i]);
1078 setup_btree_index(i, t);
1079 }
1080
1081 return 0;
1082}
1083
1084/*
1085 * Builds the btree to index the map.
1086 */
1087static int dm_table_build_index(struct dm_table *t)
1088{
1089 int r = 0;
1090 unsigned int leaf_nodes;
1091
1092 /* how many indexes will the btree have ? */
1093 leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
1094 t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
1095
1096 /* leaf layer has already been set up */
1097 t->counts[t->depth - 1] = leaf_nodes;
1098 t->index[t->depth - 1] = t->highs;
1099
1100 if (t->depth >= 2)
1101 r = setup_indexes(t);
1102
1103 return r;
1104}
1105
1106static bool integrity_profile_exists(struct gendisk *disk)
1107{
1108 return !!blk_get_integrity(disk);
1109}
1110
1111/*
1112 * Get a disk whose integrity profile reflects the table's profile.
1113 * Returns NULL if integrity support was inconsistent or unavailable.
1114 */
1115static struct gendisk *dm_table_get_integrity_disk(struct dm_table *t)
1116{
1117 struct list_head *devices = dm_table_get_devices(t);
1118 struct dm_dev_internal *dd = NULL;
1119 struct gendisk *prev_disk = NULL, *template_disk = NULL;
1120
1121 for (unsigned int i = 0; i < t->num_targets; i++) {
1122 struct dm_target *ti = dm_table_get_target(t, i);
1123
1124 if (!dm_target_passes_integrity(ti->type))
1125 goto no_integrity;
1126 }
1127
1128 list_for_each_entry(dd, devices, list) {
1129 template_disk = dd->dm_dev->bdev->bd_disk;
1130 if (!integrity_profile_exists(template_disk))
1131 goto no_integrity;
1132 else if (prev_disk &&
1133 blk_integrity_compare(prev_disk, template_disk) < 0)
1134 goto no_integrity;
1135 prev_disk = template_disk;
1136 }
1137
1138 return template_disk;
1139
1140no_integrity:
1141 if (prev_disk)
1142 DMWARN("%s: integrity not set: %s and %s profile mismatch",
1143 dm_device_name(t->md),
1144 prev_disk->disk_name,
1145 template_disk->disk_name);
1146 return NULL;
1147}
1148
1149/*
1150 * Register the mapped device for blk_integrity support if the
1151 * underlying devices have an integrity profile. But all devices may
1152 * not have matching profiles (checking all devices isn't reliable
1153 * during table load because this table may use other DM device(s) which
1154 * must be resumed before they will have an initialized integity
1155 * profile). Consequently, stacked DM devices force a 2 stage integrity
1156 * profile validation: First pass during table load, final pass during
1157 * resume.
1158 */
1159static int dm_table_register_integrity(struct dm_table *t)
1160{
1161 struct mapped_device *md = t->md;
1162 struct gendisk *template_disk = NULL;
1163
1164 /* If target handles integrity itself do not register it here. */
1165 if (t->integrity_added)
1166 return 0;
1167
1168 template_disk = dm_table_get_integrity_disk(t);
1169 if (!template_disk)
1170 return 0;
1171
1172 if (!integrity_profile_exists(dm_disk(md))) {
1173 t->integrity_supported = true;
1174 /*
1175 * Register integrity profile during table load; we can do
1176 * this because the final profile must match during resume.
1177 */
1178 blk_integrity_register(dm_disk(md),
1179 blk_get_integrity(template_disk));
1180 return 0;
1181 }
1182
1183 /*
1184 * If DM device already has an initialized integrity
1185 * profile the new profile should not conflict.
1186 */
1187 if (blk_integrity_compare(dm_disk(md), template_disk) < 0) {
1188 DMERR("%s: conflict with existing integrity profile: "
1189 "%s profile mismatch",
1190 dm_device_name(t->md),
1191 template_disk->disk_name);
1192 return 1;
1193 }
1194
1195 /* Preserve existing integrity profile */
1196 t->integrity_supported = true;
1197 return 0;
1198}
1199
1200#ifdef CONFIG_BLK_INLINE_ENCRYPTION
1201
1202struct dm_crypto_profile {
1203 struct blk_crypto_profile profile;
1204 struct mapped_device *md;
1205};
1206
1207struct dm_keyslot_evict_args {
1208 const struct blk_crypto_key *key;
1209 int err;
1210};
1211
1212static int dm_keyslot_evict_callback(struct dm_target *ti, struct dm_dev *dev,
1213 sector_t start, sector_t len, void *data)
1214{
1215 struct dm_keyslot_evict_args *args = data;
1216 int err;
1217
1218 err = blk_crypto_evict_key(dev->bdev, args->key);
1219 if (!args->err)
1220 args->err = err;
1221 /* Always try to evict the key from all devices. */
1222 return 0;
1223}
1224
1225/*
1226 * When an inline encryption key is evicted from a device-mapper device, evict
1227 * it from all the underlying devices.
1228 */
1229static int dm_keyslot_evict(struct blk_crypto_profile *profile,
1230 const struct blk_crypto_key *key, unsigned int slot)
1231{
1232 struct mapped_device *md =
1233 container_of(profile, struct dm_crypto_profile, profile)->md;
1234 struct dm_keyslot_evict_args args = { key };
1235 struct dm_table *t;
1236 int srcu_idx;
1237
1238 t = dm_get_live_table(md, &srcu_idx);
1239 if (!t)
1240 return 0;
1241
1242 for (unsigned int i = 0; i < t->num_targets; i++) {
1243 struct dm_target *ti = dm_table_get_target(t, i);
1244
1245 if (!ti->type->iterate_devices)
1246 continue;
1247 ti->type->iterate_devices(ti, dm_keyslot_evict_callback, &args);
1248 }
1249
1250 dm_put_live_table(md, srcu_idx);
1251 return args.err;
1252}
1253
1254static int
1255device_intersect_crypto_capabilities(struct dm_target *ti, struct dm_dev *dev,
1256 sector_t start, sector_t len, void *data)
1257{
1258 struct blk_crypto_profile *parent = data;
1259 struct blk_crypto_profile *child =
1260 bdev_get_queue(dev->bdev)->crypto_profile;
1261
1262 blk_crypto_intersect_capabilities(parent, child);
1263 return 0;
1264}
1265
1266void dm_destroy_crypto_profile(struct blk_crypto_profile *profile)
1267{
1268 struct dm_crypto_profile *dmcp = container_of(profile,
1269 struct dm_crypto_profile,
1270 profile);
1271
1272 if (!profile)
1273 return;
1274
1275 blk_crypto_profile_destroy(profile);
1276 kfree(dmcp);
1277}
1278
1279static void dm_table_destroy_crypto_profile(struct dm_table *t)
1280{
1281 dm_destroy_crypto_profile(t->crypto_profile);
1282 t->crypto_profile = NULL;
1283}
1284
1285/*
1286 * Constructs and initializes t->crypto_profile with a crypto profile that
1287 * represents the common set of crypto capabilities of the devices described by
1288 * the dm_table. However, if the constructed crypto profile doesn't support all
1289 * crypto capabilities that are supported by the current mapped_device, it
1290 * returns an error instead, since we don't support removing crypto capabilities
1291 * on table changes. Finally, if the constructed crypto profile is "empty" (has
1292 * no crypto capabilities at all), it just sets t->crypto_profile to NULL.
1293 */
1294static int dm_table_construct_crypto_profile(struct dm_table *t)
1295{
1296 struct dm_crypto_profile *dmcp;
1297 struct blk_crypto_profile *profile;
1298 unsigned int i;
1299 bool empty_profile = true;
1300
1301 dmcp = kmalloc(sizeof(*dmcp), GFP_KERNEL);
1302 if (!dmcp)
1303 return -ENOMEM;
1304 dmcp->md = t->md;
1305
1306 profile = &dmcp->profile;
1307 blk_crypto_profile_init(profile, 0);
1308 profile->ll_ops.keyslot_evict = dm_keyslot_evict;
1309 profile->max_dun_bytes_supported = UINT_MAX;
1310 memset(profile->modes_supported, 0xFF,
1311 sizeof(profile->modes_supported));
1312
1313 for (i = 0; i < t->num_targets; i++) {
1314 struct dm_target *ti = dm_table_get_target(t, i);
1315
1316 if (!dm_target_passes_crypto(ti->type)) {
1317 blk_crypto_intersect_capabilities(profile, NULL);
1318 break;
1319 }
1320 if (!ti->type->iterate_devices)
1321 continue;
1322 ti->type->iterate_devices(ti,
1323 device_intersect_crypto_capabilities,
1324 profile);
1325 }
1326
1327 if (t->md->queue &&
1328 !blk_crypto_has_capabilities(profile,
1329 t->md->queue->crypto_profile)) {
1330 DMERR("Inline encryption capabilities of new DM table were more restrictive than the old table's. This is not supported!");
1331 dm_destroy_crypto_profile(profile);
1332 return -EINVAL;
1333 }
1334
1335 /*
1336 * If the new profile doesn't actually support any crypto capabilities,
1337 * we may as well represent it with a NULL profile.
1338 */
1339 for (i = 0; i < ARRAY_SIZE(profile->modes_supported); i++) {
1340 if (profile->modes_supported[i]) {
1341 empty_profile = false;
1342 break;
1343 }
1344 }
1345
1346 if (empty_profile) {
1347 dm_destroy_crypto_profile(profile);
1348 profile = NULL;
1349 }
1350
1351 /*
1352 * t->crypto_profile is only set temporarily while the table is being
1353 * set up, and it gets set to NULL after the profile has been
1354 * transferred to the request_queue.
1355 */
1356 t->crypto_profile = profile;
1357
1358 return 0;
1359}
1360
1361static void dm_update_crypto_profile(struct request_queue *q,
1362 struct dm_table *t)
1363{
1364 if (!t->crypto_profile)
1365 return;
1366
1367 /* Make the crypto profile less restrictive. */
1368 if (!q->crypto_profile) {
1369 blk_crypto_register(t->crypto_profile, q);
1370 } else {
1371 blk_crypto_update_capabilities(q->crypto_profile,
1372 t->crypto_profile);
1373 dm_destroy_crypto_profile(t->crypto_profile);
1374 }
1375 t->crypto_profile = NULL;
1376}
1377
1378#else /* CONFIG_BLK_INLINE_ENCRYPTION */
1379
1380static int dm_table_construct_crypto_profile(struct dm_table *t)
1381{
1382 return 0;
1383}
1384
1385void dm_destroy_crypto_profile(struct blk_crypto_profile *profile)
1386{
1387}
1388
1389static void dm_table_destroy_crypto_profile(struct dm_table *t)
1390{
1391}
1392
1393static void dm_update_crypto_profile(struct request_queue *q,
1394 struct dm_table *t)
1395{
1396}
1397
1398#endif /* !CONFIG_BLK_INLINE_ENCRYPTION */
1399
1400/*
1401 * Prepares the table for use by building the indices,
1402 * setting the type, and allocating mempools.
1403 */
1404int dm_table_complete(struct dm_table *t)
1405{
1406 int r;
1407
1408 r = dm_table_determine_type(t);
1409 if (r) {
1410 DMERR("unable to determine table type");
1411 return r;
1412 }
1413
1414 r = dm_table_build_index(t);
1415 if (r) {
1416 DMERR("unable to build btrees");
1417 return r;
1418 }
1419
1420 r = dm_table_register_integrity(t);
1421 if (r) {
1422 DMERR("could not register integrity profile.");
1423 return r;
1424 }
1425
1426 r = dm_table_construct_crypto_profile(t);
1427 if (r) {
1428 DMERR("could not construct crypto profile.");
1429 return r;
1430 }
1431
1432 r = dm_table_alloc_md_mempools(t, t->md);
1433 if (r)
1434 DMERR("unable to allocate mempools");
1435
1436 return r;
1437}
1438
1439static DEFINE_MUTEX(_event_lock);
1440void dm_table_event_callback(struct dm_table *t,
1441 void (*fn)(void *), void *context)
1442{
1443 mutex_lock(&_event_lock);
1444 t->event_fn = fn;
1445 t->event_context = context;
1446 mutex_unlock(&_event_lock);
1447}
1448
1449void dm_table_event(struct dm_table *t)
1450{
1451 mutex_lock(&_event_lock);
1452 if (t->event_fn)
1453 t->event_fn(t->event_context);
1454 mutex_unlock(&_event_lock);
1455}
1456EXPORT_SYMBOL(dm_table_event);
1457
1458inline sector_t dm_table_get_size(struct dm_table *t)
1459{
1460 return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
1461}
1462EXPORT_SYMBOL(dm_table_get_size);
1463
1464/*
1465 * Search the btree for the correct target.
1466 *
1467 * Caller should check returned pointer for NULL
1468 * to trap I/O beyond end of device.
1469 */
1470struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
1471{
1472 unsigned int l, n = 0, k = 0;
1473 sector_t *node;
1474
1475 if (unlikely(sector >= dm_table_get_size(t)))
1476 return NULL;
1477
1478 for (l = 0; l < t->depth; l++) {
1479 n = get_child(n, k);
1480 node = get_node(t, l, n);
1481
1482 for (k = 0; k < KEYS_PER_NODE; k++)
1483 if (node[k] >= sector)
1484 break;
1485 }
1486
1487 return &t->targets[(KEYS_PER_NODE * n) + k];
1488}
1489
1490static int device_not_poll_capable(struct dm_target *ti, struct dm_dev *dev,
1491 sector_t start, sector_t len, void *data)
1492{
1493 struct request_queue *q = bdev_get_queue(dev->bdev);
1494
1495 return !test_bit(QUEUE_FLAG_POLL, &q->queue_flags);
1496}
1497
1498/*
1499 * type->iterate_devices() should be called when the sanity check needs to
1500 * iterate and check all underlying data devices. iterate_devices() will
1501 * iterate all underlying data devices until it encounters a non-zero return
1502 * code, returned by whether the input iterate_devices_callout_fn, or
1503 * iterate_devices() itself internally.
1504 *
1505 * For some target type (e.g. dm-stripe), one call of iterate_devices() may
1506 * iterate multiple underlying devices internally, in which case a non-zero
1507 * return code returned by iterate_devices_callout_fn will stop the iteration
1508 * in advance.
1509 *
1510 * Cases requiring _any_ underlying device supporting some kind of attribute,
1511 * should use the iteration structure like dm_table_any_dev_attr(), or call
1512 * it directly. @func should handle semantics of positive examples, e.g.
1513 * capable of something.
1514 *
1515 * Cases requiring _all_ underlying devices supporting some kind of attribute,
1516 * should use the iteration structure like dm_table_supports_nowait() or
1517 * dm_table_supports_discards(). Or introduce dm_table_all_devs_attr() that
1518 * uses an @anti_func that handle semantics of counter examples, e.g. not
1519 * capable of something. So: return !dm_table_any_dev_attr(t, anti_func, data);
1520 */
1521static bool dm_table_any_dev_attr(struct dm_table *t,
1522 iterate_devices_callout_fn func, void *data)
1523{
1524 for (unsigned int i = 0; i < t->num_targets; i++) {
1525 struct dm_target *ti = dm_table_get_target(t, i);
1526
1527 if (ti->type->iterate_devices &&
1528 ti->type->iterate_devices(ti, func, data))
1529 return true;
1530 }
1531
1532 return false;
1533}
1534
1535static int count_device(struct dm_target *ti, struct dm_dev *dev,
1536 sector_t start, sector_t len, void *data)
1537{
1538 unsigned *num_devices = data;
1539
1540 (*num_devices)++;
1541
1542 return 0;
1543}
1544
1545static bool dm_table_supports_poll(struct dm_table *t)
1546{
1547 for (unsigned int i = 0; i < t->num_targets; i++) {
1548 struct dm_target *ti = dm_table_get_target(t, i);
1549
1550 if (!ti->type->iterate_devices ||
1551 ti->type->iterate_devices(ti, device_not_poll_capable, NULL))
1552 return false;
1553 }
1554
1555 return true;
1556}
1557
1558/*
1559 * Check whether a table has no data devices attached using each
1560 * target's iterate_devices method.
1561 * Returns false if the result is unknown because a target doesn't
1562 * support iterate_devices.
1563 */
1564bool dm_table_has_no_data_devices(struct dm_table *t)
1565{
1566 for (unsigned int i = 0; i < t->num_targets; i++) {
1567 struct dm_target *ti = dm_table_get_target(t, i);
1568 unsigned num_devices = 0;
1569
1570 if (!ti->type->iterate_devices)
1571 return false;
1572
1573 ti->type->iterate_devices(ti, count_device, &num_devices);
1574 if (num_devices)
1575 return false;
1576 }
1577
1578 return true;
1579}
1580
1581static int device_not_zoned_model(struct dm_target *ti, struct dm_dev *dev,
1582 sector_t start, sector_t len, void *data)
1583{
1584 struct request_queue *q = bdev_get_queue(dev->bdev);
1585 enum blk_zoned_model *zoned_model = data;
1586
1587 return blk_queue_zoned_model(q) != *zoned_model;
1588}
1589
1590/*
1591 * Check the device zoned model based on the target feature flag. If the target
1592 * has the DM_TARGET_ZONED_HM feature flag set, host-managed zoned devices are
1593 * also accepted but all devices must have the same zoned model. If the target
1594 * has the DM_TARGET_MIXED_ZONED_MODEL feature set, the devices can have any
1595 * zoned model with all zoned devices having the same zone size.
1596 */
1597static bool dm_table_supports_zoned_model(struct dm_table *t,
1598 enum blk_zoned_model zoned_model)
1599{
1600 for (unsigned int i = 0; i < t->num_targets; i++) {
1601 struct dm_target *ti = dm_table_get_target(t, i);
1602
1603 if (dm_target_supports_zoned_hm(ti->type)) {
1604 if (!ti->type->iterate_devices ||
1605 ti->type->iterate_devices(ti, device_not_zoned_model,
1606 &zoned_model))
1607 return false;
1608 } else if (!dm_target_supports_mixed_zoned_model(ti->type)) {
1609 if (zoned_model == BLK_ZONED_HM)
1610 return false;
1611 }
1612 }
1613
1614 return true;
1615}
1616
1617static int device_not_matches_zone_sectors(struct dm_target *ti, struct dm_dev *dev,
1618 sector_t start, sector_t len, void *data)
1619{
1620 unsigned int *zone_sectors = data;
1621
1622 if (!bdev_is_zoned(dev->bdev))
1623 return 0;
1624 return bdev_zone_sectors(dev->bdev) != *zone_sectors;
1625}
1626
1627/*
1628 * Check consistency of zoned model and zone sectors across all targets. For
1629 * zone sectors, if the destination device is a zoned block device, it shall
1630 * have the specified zone_sectors.
1631 */
1632static int validate_hardware_zoned_model(struct dm_table *t,
1633 enum blk_zoned_model zoned_model,
1634 unsigned int zone_sectors)
1635{
1636 if (zoned_model == BLK_ZONED_NONE)
1637 return 0;
1638
1639 if (!dm_table_supports_zoned_model(t, zoned_model)) {
1640 DMERR("%s: zoned model is not consistent across all devices",
1641 dm_device_name(t->md));
1642 return -EINVAL;
1643 }
1644
1645 /* Check zone size validity and compatibility */
1646 if (!zone_sectors || !is_power_of_2(zone_sectors))
1647 return -EINVAL;
1648
1649 if (dm_table_any_dev_attr(t, device_not_matches_zone_sectors, &zone_sectors)) {
1650 DMERR("%s: zone sectors is not consistent across all zoned devices",
1651 dm_device_name(t->md));
1652 return -EINVAL;
1653 }
1654
1655 return 0;
1656}
1657
1658/*
1659 * Establish the new table's queue_limits and validate them.
1660 */
1661int dm_calculate_queue_limits(struct dm_table *t,
1662 struct queue_limits *limits)
1663{
1664 struct queue_limits ti_limits;
1665 enum blk_zoned_model zoned_model = BLK_ZONED_NONE;
1666 unsigned int zone_sectors = 0;
1667
1668 blk_set_stacking_limits(limits);
1669
1670 for (unsigned int i = 0; i < t->num_targets; i++) {
1671 struct dm_target *ti = dm_table_get_target(t, i);
1672
1673 blk_set_stacking_limits(&ti_limits);
1674
1675 if (!ti->type->iterate_devices)
1676 goto combine_limits;
1677
1678 /*
1679 * Combine queue limits of all the devices this target uses.
1680 */
1681 ti->type->iterate_devices(ti, dm_set_device_limits,
1682 &ti_limits);
1683
1684 if (zoned_model == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
1685 /*
1686 * After stacking all limits, validate all devices
1687 * in table support this zoned model and zone sectors.
1688 */
1689 zoned_model = ti_limits.zoned;
1690 zone_sectors = ti_limits.chunk_sectors;
1691 }
1692
1693 /* Set I/O hints portion of queue limits */
1694 if (ti->type->io_hints)
1695 ti->type->io_hints(ti, &ti_limits);
1696
1697 /*
1698 * Check each device area is consistent with the target's
1699 * overall queue limits.
1700 */
1701 if (ti->type->iterate_devices(ti, device_area_is_invalid,
1702 &ti_limits))
1703 return -EINVAL;
1704
1705combine_limits:
1706 /*
1707 * Merge this target's queue limits into the overall limits
1708 * for the table.
1709 */
1710 if (blk_stack_limits(limits, &ti_limits, 0) < 0)
1711 DMWARN("%s: adding target device "
1712 "(start sect %llu len %llu) "
1713 "caused an alignment inconsistency",
1714 dm_device_name(t->md),
1715 (unsigned long long) ti->begin,
1716 (unsigned long long) ti->len);
1717 }
1718
1719 /*
1720 * Verify that the zoned model and zone sectors, as determined before
1721 * any .io_hints override, are the same across all devices in the table.
1722 * - this is especially relevant if .io_hints is emulating a disk-managed
1723 * zoned model (aka BLK_ZONED_NONE) on host-managed zoned block devices.
1724 * BUT...
1725 */
1726 if (limits->zoned != BLK_ZONED_NONE) {
1727 /*
1728 * ...IF the above limits stacking determined a zoned model
1729 * validate that all of the table's devices conform to it.
1730 */
1731 zoned_model = limits->zoned;
1732 zone_sectors = limits->chunk_sectors;
1733 }
1734 if (validate_hardware_zoned_model(t, zoned_model, zone_sectors))
1735 return -EINVAL;
1736
1737 return validate_hardware_logical_block_alignment(t, limits);
1738}
1739
1740/*
1741 * Verify that all devices have an integrity profile that matches the
1742 * DM device's registered integrity profile. If the profiles don't
1743 * match then unregister the DM device's integrity profile.
1744 */
1745static void dm_table_verify_integrity(struct dm_table *t)
1746{
1747 struct gendisk *template_disk = NULL;
1748
1749 if (t->integrity_added)
1750 return;
1751
1752 if (t->integrity_supported) {
1753 /*
1754 * Verify that the original integrity profile
1755 * matches all the devices in this table.
1756 */
1757 template_disk = dm_table_get_integrity_disk(t);
1758 if (template_disk &&
1759 blk_integrity_compare(dm_disk(t->md), template_disk) >= 0)
1760 return;
1761 }
1762
1763 if (integrity_profile_exists(dm_disk(t->md))) {
1764 DMWARN("%s: unable to establish an integrity profile",
1765 dm_device_name(t->md));
1766 blk_integrity_unregister(dm_disk(t->md));
1767 }
1768}
1769
1770static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
1771 sector_t start, sector_t len, void *data)
1772{
1773 unsigned long flush = (unsigned long) data;
1774 struct request_queue *q = bdev_get_queue(dev->bdev);
1775
1776 return (q->queue_flags & flush);
1777}
1778
1779static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush)
1780{
1781 /*
1782 * Require at least one underlying device to support flushes.
1783 * t->devices includes internal dm devices such as mirror logs
1784 * so we need to use iterate_devices here, which targets
1785 * supporting flushes must provide.
1786 */
1787 for (unsigned int i = 0; i < t->num_targets; i++) {
1788 struct dm_target *ti = dm_table_get_target(t, i);
1789
1790 if (!ti->num_flush_bios)
1791 continue;
1792
1793 if (ti->flush_supported)
1794 return true;
1795
1796 if (ti->type->iterate_devices &&
1797 ti->type->iterate_devices(ti, device_flush_capable, (void *) flush))
1798 return true;
1799 }
1800
1801 return false;
1802}
1803
1804static int device_dax_write_cache_enabled(struct dm_target *ti,
1805 struct dm_dev *dev, sector_t start,
1806 sector_t len, void *data)
1807{
1808 struct dax_device *dax_dev = dev->dax_dev;
1809
1810 if (!dax_dev)
1811 return false;
1812
1813 if (dax_write_cache_enabled(dax_dev))
1814 return true;
1815 return false;
1816}
1817
1818static int device_is_rotational(struct dm_target *ti, struct dm_dev *dev,
1819 sector_t start, sector_t len, void *data)
1820{
1821 return !bdev_nonrot(dev->bdev);
1822}
1823
1824static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
1825 sector_t start, sector_t len, void *data)
1826{
1827 struct request_queue *q = bdev_get_queue(dev->bdev);
1828
1829 return !blk_queue_add_random(q);
1830}
1831
1832static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev,
1833 sector_t start, sector_t len, void *data)
1834{
1835 struct request_queue *q = bdev_get_queue(dev->bdev);
1836
1837 return !q->limits.max_write_zeroes_sectors;
1838}
1839
1840static bool dm_table_supports_write_zeroes(struct dm_table *t)
1841{
1842 for (unsigned int i = 0; i < t->num_targets; i++) {
1843 struct dm_target *ti = dm_table_get_target(t, i);
1844
1845 if (!ti->num_write_zeroes_bios)
1846 return false;
1847
1848 if (!ti->type->iterate_devices ||
1849 ti->type->iterate_devices(ti, device_not_write_zeroes_capable, NULL))
1850 return false;
1851 }
1852
1853 return true;
1854}
1855
1856static int device_not_nowait_capable(struct dm_target *ti, struct dm_dev *dev,
1857 sector_t start, sector_t len, void *data)
1858{
1859 return !bdev_nowait(dev->bdev);
1860}
1861
1862static bool dm_table_supports_nowait(struct dm_table *t)
1863{
1864 for (unsigned int i = 0; i < t->num_targets; i++) {
1865 struct dm_target *ti = dm_table_get_target(t, i);
1866
1867 if (!dm_target_supports_nowait(ti->type))
1868 return false;
1869
1870 if (!ti->type->iterate_devices ||
1871 ti->type->iterate_devices(ti, device_not_nowait_capable, NULL))
1872 return false;
1873 }
1874
1875 return true;
1876}
1877
1878static int device_not_discard_capable(struct dm_target *ti, struct dm_dev *dev,
1879 sector_t start, sector_t len, void *data)
1880{
1881 return !bdev_max_discard_sectors(dev->bdev);
1882}
1883
1884static bool dm_table_supports_discards(struct dm_table *t)
1885{
1886 for (unsigned int i = 0; i < t->num_targets; i++) {
1887 struct dm_target *ti = dm_table_get_target(t, i);
1888
1889 if (!ti->num_discard_bios)
1890 return false;
1891
1892 /*
1893 * Either the target provides discard support (as implied by setting
1894 * 'discards_supported') or it relies on _all_ data devices having
1895 * discard support.
1896 */
1897 if (!ti->discards_supported &&
1898 (!ti->type->iterate_devices ||
1899 ti->type->iterate_devices(ti, device_not_discard_capable, NULL)))
1900 return false;
1901 }
1902
1903 return true;
1904}
1905
1906static int device_not_secure_erase_capable(struct dm_target *ti,
1907 struct dm_dev *dev, sector_t start,
1908 sector_t len, void *data)
1909{
1910 return !bdev_max_secure_erase_sectors(dev->bdev);
1911}
1912
1913static bool dm_table_supports_secure_erase(struct dm_table *t)
1914{
1915 for (unsigned int i = 0; i < t->num_targets; i++) {
1916 struct dm_target *ti = dm_table_get_target(t, i);
1917
1918 if (!ti->num_secure_erase_bios)
1919 return false;
1920
1921 if (!ti->type->iterate_devices ||
1922 ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL))
1923 return false;
1924 }
1925
1926 return true;
1927}
1928
1929static int device_requires_stable_pages(struct dm_target *ti,
1930 struct dm_dev *dev, sector_t start,
1931 sector_t len, void *data)
1932{
1933 return bdev_stable_writes(dev->bdev);
1934}
1935
1936int dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1937 struct queue_limits *limits)
1938{
1939 bool wc = false, fua = false;
1940 int r;
1941
1942 /*
1943 * Copy table's limits to the DM device's request_queue
1944 */
1945 q->limits = *limits;
1946
1947 if (dm_table_supports_nowait(t))
1948 blk_queue_flag_set(QUEUE_FLAG_NOWAIT, q);
1949 else
1950 blk_queue_flag_clear(QUEUE_FLAG_NOWAIT, q);
1951
1952 if (!dm_table_supports_discards(t)) {
1953 q->limits.max_discard_sectors = 0;
1954 q->limits.max_hw_discard_sectors = 0;
1955 q->limits.discard_granularity = 0;
1956 q->limits.discard_alignment = 0;
1957 q->limits.discard_misaligned = 0;
1958 }
1959
1960 if (!dm_table_supports_secure_erase(t))
1961 q->limits.max_secure_erase_sectors = 0;
1962
1963 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) {
1964 wc = true;
1965 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA)))
1966 fua = true;
1967 }
1968 blk_queue_write_cache(q, wc, fua);
1969
1970 if (dm_table_supports_dax(t, device_not_dax_capable)) {
1971 blk_queue_flag_set(QUEUE_FLAG_DAX, q);
1972 if (dm_table_supports_dax(t, device_not_dax_synchronous_capable))
1973 set_dax_synchronous(t->md->dax_dev);
1974 }
1975 else
1976 blk_queue_flag_clear(QUEUE_FLAG_DAX, q);
1977
1978 if (dm_table_any_dev_attr(t, device_dax_write_cache_enabled, NULL))
1979 dax_write_cache(t->md->dax_dev, true);
1980
1981 /* Ensure that all underlying devices are non-rotational. */
1982 if (dm_table_any_dev_attr(t, device_is_rotational, NULL))
1983 blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
1984 else
1985 blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
1986
1987 if (!dm_table_supports_write_zeroes(t))
1988 q->limits.max_write_zeroes_sectors = 0;
1989
1990 dm_table_verify_integrity(t);
1991
1992 /*
1993 * Some devices don't use blk_integrity but still want stable pages
1994 * because they do their own checksumming.
1995 * If any underlying device requires stable pages, a table must require
1996 * them as well. Only targets that support iterate_devices are considered:
1997 * don't want error, zero, etc to require stable pages.
1998 */
1999 if (dm_table_any_dev_attr(t, device_requires_stable_pages, NULL))
2000 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, q);
2001 else
2002 blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, q);
2003
2004 /*
2005 * Determine whether or not this queue's I/O timings contribute
2006 * to the entropy pool, Only request-based targets use this.
2007 * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
2008 * have it set.
2009 */
2010 if (blk_queue_add_random(q) &&
2011 dm_table_any_dev_attr(t, device_is_not_random, NULL))
2012 blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
2013
2014 /*
2015 * For a zoned target, setup the zones related queue attributes
2016 * and resources necessary for zone append emulation if necessary.
2017 */
2018 if (blk_queue_is_zoned(q)) {
2019 r = dm_set_zones_restrictions(t, q);
2020 if (r)
2021 return r;
2022 if (!static_key_enabled(&zoned_enabled.key))
2023 static_branch_enable(&zoned_enabled);
2024 }
2025
2026 dm_update_crypto_profile(q, t);
2027 disk_update_readahead(t->md->disk);
2028
2029 /*
2030 * Check for request-based device is left to
2031 * dm_mq_init_request_queue()->blk_mq_init_allocated_queue().
2032 *
2033 * For bio-based device, only set QUEUE_FLAG_POLL when all
2034 * underlying devices supporting polling.
2035 */
2036 if (__table_type_bio_based(t->type)) {
2037 if (dm_table_supports_poll(t))
2038 blk_queue_flag_set(QUEUE_FLAG_POLL, q);
2039 else
2040 blk_queue_flag_clear(QUEUE_FLAG_POLL, q);
2041 }
2042
2043 return 0;
2044}
2045
2046struct list_head *dm_table_get_devices(struct dm_table *t)
2047{
2048 return &t->devices;
2049}
2050
2051fmode_t dm_table_get_mode(struct dm_table *t)
2052{
2053 return t->mode;
2054}
2055EXPORT_SYMBOL(dm_table_get_mode);
2056
2057enum suspend_mode {
2058 PRESUSPEND,
2059 PRESUSPEND_UNDO,
2060 POSTSUSPEND,
2061};
2062
2063static void suspend_targets(struct dm_table *t, enum suspend_mode mode)
2064{
2065 lockdep_assert_held(&t->md->suspend_lock);
2066
2067 for (unsigned int i = 0; i < t->num_targets; i++) {
2068 struct dm_target *ti = dm_table_get_target(t, i);
2069
2070 switch (mode) {
2071 case PRESUSPEND:
2072 if (ti->type->presuspend)
2073 ti->type->presuspend(ti);
2074 break;
2075 case PRESUSPEND_UNDO:
2076 if (ti->type->presuspend_undo)
2077 ti->type->presuspend_undo(ti);
2078 break;
2079 case POSTSUSPEND:
2080 if (ti->type->postsuspend)
2081 ti->type->postsuspend(ti);
2082 break;
2083 }
2084 }
2085}
2086
2087void dm_table_presuspend_targets(struct dm_table *t)
2088{
2089 if (!t)
2090 return;
2091
2092 suspend_targets(t, PRESUSPEND);
2093}
2094
2095void dm_table_presuspend_undo_targets(struct dm_table *t)
2096{
2097 if (!t)
2098 return;
2099
2100 suspend_targets(t, PRESUSPEND_UNDO);
2101}
2102
2103void dm_table_postsuspend_targets(struct dm_table *t)
2104{
2105 if (!t)
2106 return;
2107
2108 suspend_targets(t, POSTSUSPEND);
2109}
2110
2111int dm_table_resume_targets(struct dm_table *t)
2112{
2113 unsigned int i;
2114 int r = 0;
2115
2116 lockdep_assert_held(&t->md->suspend_lock);
2117
2118 for (i = 0; i < t->num_targets; i++) {
2119 struct dm_target *ti = dm_table_get_target(t, i);
2120
2121 if (!ti->type->preresume)
2122 continue;
2123
2124 r = ti->type->preresume(ti);
2125 if (r) {
2126 DMERR("%s: %s: preresume failed, error = %d",
2127 dm_device_name(t->md), ti->type->name, r);
2128 return r;
2129 }
2130 }
2131
2132 for (i = 0; i < t->num_targets; i++) {
2133 struct dm_target *ti = dm_table_get_target(t, i);
2134
2135 if (ti->type->resume)
2136 ti->type->resume(ti);
2137 }
2138
2139 return 0;
2140}
2141
2142struct mapped_device *dm_table_get_md(struct dm_table *t)
2143{
2144 return t->md;
2145}
2146EXPORT_SYMBOL(dm_table_get_md);
2147
2148const char *dm_table_device_name(struct dm_table *t)
2149{
2150 return dm_device_name(t->md);
2151}
2152EXPORT_SYMBOL_GPL(dm_table_device_name);
2153
2154void dm_table_run_md_queue_async(struct dm_table *t)
2155{
2156 if (!dm_table_request_based(t))
2157 return;
2158
2159 if (t->md->queue)
2160 blk_mq_run_hw_queues(t->md->queue, true);
2161}
2162EXPORT_SYMBOL(dm_table_run_md_queue_async);
2163