2 * Copyright (C) 2001 Sistina Software (UK) Limited.
3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
5 * This file is released under the GPL.
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 #include <linux/blk-mq.h>
22 #include <linux/mount.h>
23 #include <linux/dax.h>
25 #define DM_MSG_PREFIX "table"
27 #define NODE_SIZE L1_CACHE_BYTES
28 #define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
29 #define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
32 * Similar to ceiling(log_size(n))
34 static unsigned int int_log(unsigned int n, unsigned int base)
39 n = dm_div_up(n, base);
47 * Calculate the index of the child node of the n'th node k'th key.
49 static inline unsigned int get_child(unsigned int n, unsigned int k)
51 return (n * CHILDREN_PER_NODE) + k;
55 * Return the n'th node of level l from table t.
57 static inline sector_t *get_node(struct dm_table *t,
58 unsigned int l, unsigned int n)
60 return t->index[l] + (n * KEYS_PER_NODE);
64 * Return the highest key that you could lookup from the n'th
65 * node on level l of the btree.
67 static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
69 for (; l < t->depth - 1; l++)
70 n = get_child(n, CHILDREN_PER_NODE - 1);
72 if (n >= t->counts[l])
73 return (sector_t) - 1;
75 return get_node(t, l, n)[KEYS_PER_NODE - 1];
79 * Fills in a level of the btree based on the highs of the level
82 static int setup_btree_index(unsigned int l, struct dm_table *t)
87 for (n = 0U; n < t->counts[l]; n++) {
88 node = get_node(t, l, n);
90 for (k = 0U; k < KEYS_PER_NODE; k++)
91 node[k] = high(t, l + 1, get_child(n, k));
97 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
103 * Check that we're not going to overflow.
105 if (nmemb > (ULONG_MAX / elem_size))
108 size = nmemb * elem_size;
109 addr = vzalloc(size);
113 EXPORT_SYMBOL(dm_vcalloc);
116 * highs, and targets are managed as dynamic arrays during a
119 static int alloc_targets(struct dm_table *t, unsigned int num)
122 struct dm_target *n_targets;
125 * Allocate both the target array and offset array at once.
127 n_highs = (sector_t *) dm_vcalloc(num, sizeof(struct dm_target) +
132 n_targets = (struct dm_target *) (n_highs + num);
134 memset(n_highs, -1, sizeof(*n_highs) * num);
137 t->num_allocated = num;
139 t->targets = n_targets;
144 int dm_table_create(struct dm_table **result, fmode_t mode,
145 unsigned num_targets, struct mapped_device *md)
149 if (num_targets > DM_MAX_TARGETS)
152 t = kzalloc(sizeof(*t), GFP_KERNEL);
157 INIT_LIST_HEAD(&t->devices);
160 num_targets = KEYS_PER_NODE;
162 num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
169 if (alloc_targets(t, num_targets)) {
174 t->type = DM_TYPE_NONE;
181 static void free_devices(struct list_head *devices, struct mapped_device *md)
183 struct list_head *tmp, *next;
185 list_for_each_safe(tmp, next, devices) {
186 struct dm_dev_internal *dd =
187 list_entry(tmp, struct dm_dev_internal, list);
188 DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
189 dm_device_name(md), dd->dm_dev->name);
190 dm_put_table_device(md, dd->dm_dev);
195 void dm_table_destroy(struct dm_table *t)
202 /* free the indexes */
204 vfree(t->index[t->depth - 2]);
206 /* free the targets */
207 for (i = 0; i < t->num_targets; i++) {
208 struct dm_target *tgt = t->targets + i;
213 dm_put_target_type(tgt->type);
218 /* free the device list */
219 free_devices(&t->devices, t->md);
221 dm_free_md_mempools(t->mempools);
227 * See if we've already got a device in the list.
229 static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
231 struct dm_dev_internal *dd;
233 list_for_each_entry (dd, l, list)
234 if (dd->dm_dev->bdev->bd_dev == dev)
241 * If possible, this checks an area of a destination device is invalid.
243 static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
244 sector_t start, sector_t len, void *data)
246 struct queue_limits *limits = data;
247 struct block_device *bdev = dev->bdev;
249 i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
250 unsigned short logical_block_size_sectors =
251 limits->logical_block_size >> SECTOR_SHIFT;
252 char b[BDEVNAME_SIZE];
257 if ((start >= dev_size) || (start + len > dev_size)) {
258 DMWARN("%s: %s too small for target: "
259 "start=%llu, len=%llu, dev_size=%llu",
260 dm_device_name(ti->table->md), bdevname(bdev, b),
261 (unsigned long long)start,
262 (unsigned long long)len,
263 (unsigned long long)dev_size);
268 * If the target is mapped to zoned block device(s), check
269 * that the zones are not partially mapped.
271 if (bdev_zoned_model(bdev) != BLK_ZONED_NONE) {
272 unsigned int zone_sectors = bdev_zone_sectors(bdev);
274 if (start & (zone_sectors - 1)) {
275 DMWARN("%s: start=%llu not aligned to h/w zone size %u of %s",
276 dm_device_name(ti->table->md),
277 (unsigned long long)start,
278 zone_sectors, bdevname(bdev, b));
283 * Note: The last zone of a zoned block device may be smaller
284 * than other zones. So for a target mapping the end of a
285 * zoned block device with such a zone, len would not be zone
286 * aligned. We do not allow such last smaller zone to be part
287 * of the mapping here to ensure that mappings with multiple
288 * devices do not end up with a smaller zone in the middle of
291 if (len & (zone_sectors - 1)) {
292 DMWARN("%s: len=%llu not aligned to h/w zone size %u of %s",
293 dm_device_name(ti->table->md),
294 (unsigned long long)len,
295 zone_sectors, bdevname(bdev, b));
300 if (logical_block_size_sectors <= 1)
303 if (start & (logical_block_size_sectors - 1)) {
304 DMWARN("%s: start=%llu not aligned to h/w "
305 "logical block size %u of %s",
306 dm_device_name(ti->table->md),
307 (unsigned long long)start,
308 limits->logical_block_size, bdevname(bdev, b));
312 if (len & (logical_block_size_sectors - 1)) {
313 DMWARN("%s: len=%llu not aligned to h/w "
314 "logical block size %u of %s",
315 dm_device_name(ti->table->md),
316 (unsigned long long)len,
317 limits->logical_block_size, bdevname(bdev, b));
325 * This upgrades the mode on an already open dm_dev, being
326 * careful to leave things as they were if we fail to reopen the
327 * device and not to touch the existing bdev field in case
328 * it is accessed concurrently.
330 static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
331 struct mapped_device *md)
334 struct dm_dev *old_dev, *new_dev;
336 old_dev = dd->dm_dev;
338 r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
339 dd->dm_dev->mode | new_mode, &new_dev);
343 dd->dm_dev = new_dev;
344 dm_put_table_device(md, old_dev);
350 * Convert the path to a device
352 dev_t dm_get_dev_t(const char *path)
355 struct block_device *bdev;
357 bdev = lookup_bdev(path);
359 dev = name_to_dev_t(path);
367 EXPORT_SYMBOL_GPL(dm_get_dev_t);
370 * Add a device to the list, or just increment the usage count if
371 * it's already present.
373 int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
374 struct dm_dev **result)
378 unsigned int major, minor;
380 struct dm_dev_internal *dd;
381 struct dm_table *t = ti->table;
385 if (sscanf(path, "%u:%u%c", &major, &minor, &dummy) == 2) {
386 /* Extract the major/minor numbers */
387 dev = MKDEV(major, minor);
388 if (MAJOR(dev) != major || MINOR(dev) != minor)
391 dev = dm_get_dev_t(path);
396 dd = find_device(&t->devices, dev);
398 dd = kmalloc(sizeof(*dd), GFP_KERNEL);
402 if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) {
407 refcount_set(&dd->count, 1);
408 list_add(&dd->list, &t->devices);
411 } else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
412 r = upgrade_mode(dd, mode, t->md);
416 refcount_inc(&dd->count);
418 *result = dd->dm_dev;
421 EXPORT_SYMBOL(dm_get_device);
423 static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
424 sector_t start, sector_t len, void *data)
426 struct queue_limits *limits = data;
427 struct block_device *bdev = dev->bdev;
428 struct request_queue *q = bdev_get_queue(bdev);
429 char b[BDEVNAME_SIZE];
432 DMWARN("%s: Cannot set limits for nonexistent device %s",
433 dm_device_name(ti->table->md), bdevname(bdev, b));
437 if (blk_stack_limits(limits, &q->limits,
438 get_start_sect(bdev) + start) < 0)
439 DMWARN("%s: adding target device %s caused an alignment inconsistency: "
440 "physical_block_size=%u, logical_block_size=%u, "
441 "alignment_offset=%u, start=%llu",
442 dm_device_name(ti->table->md), bdevname(bdev, b),
443 q->limits.physical_block_size,
444 q->limits.logical_block_size,
445 q->limits.alignment_offset,
446 (unsigned long long) start << SECTOR_SHIFT);
451 * Decrement a device's use count and remove it if necessary.
453 void dm_put_device(struct dm_target *ti, struct dm_dev *d)
456 struct list_head *devices = &ti->table->devices;
457 struct dm_dev_internal *dd;
459 list_for_each_entry(dd, devices, list) {
460 if (dd->dm_dev == d) {
466 DMWARN("%s: device %s not in table devices list",
467 dm_device_name(ti->table->md), d->name);
470 if (refcount_dec_and_test(&dd->count)) {
471 dm_put_table_device(ti->table->md, d);
476 EXPORT_SYMBOL(dm_put_device);
479 * Checks to see if the target joins onto the end of the table.
481 static int adjoin(struct dm_table *table, struct dm_target *ti)
483 struct dm_target *prev;
485 if (!table->num_targets)
488 prev = &table->targets[table->num_targets - 1];
489 return (ti->begin == (prev->begin + prev->len));
493 * Used to dynamically allocate the arg array.
495 * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
496 * process messages even if some device is suspended. These messages have a
497 * small fixed number of arguments.
499 * On the other hand, dm-switch needs to process bulk data using messages and
500 * excessive use of GFP_NOIO could cause trouble.
502 static char **realloc_argv(unsigned *size, char **old_argv)
509 new_size = *size * 2;
515 argv = kmalloc_array(new_size, sizeof(*argv), gfp);
516 if (argv && old_argv) {
517 memcpy(argv, old_argv, *size * sizeof(*argv));
526 * Destructively splits up the argument list to pass to ctr.
528 int dm_split_args(int *argc, char ***argvp, char *input)
530 char *start, *end = input, *out, **argv = NULL;
531 unsigned array_size = 0;
540 argv = realloc_argv(&array_size, argv);
545 /* Skip whitespace */
546 start = skip_spaces(end);
549 break; /* success, we hit the end */
551 /* 'out' is used to remove any back-quotes */
554 /* Everything apart from '\0' can be quoted */
555 if (*end == '\\' && *(end + 1)) {
562 break; /* end of token */
567 /* have we already filled the array ? */
568 if ((*argc + 1) > array_size) {
569 argv = realloc_argv(&array_size, argv);
574 /* we know this is whitespace */
578 /* terminate the string and put it in the array */
589 * Impose necessary and sufficient conditions on a devices's table such
590 * that any incoming bio which respects its logical_block_size can be
591 * processed successfully. If it falls across the boundary between
592 * two or more targets, the size of each piece it gets split into must
593 * be compatible with the logical_block_size of the target processing it.
595 static int validate_hardware_logical_block_alignment(struct dm_table *table,
596 struct queue_limits *limits)
599 * This function uses arithmetic modulo the logical_block_size
600 * (in units of 512-byte sectors).
602 unsigned short device_logical_block_size_sects =
603 limits->logical_block_size >> SECTOR_SHIFT;
606 * Offset of the start of the next table entry, mod logical_block_size.
608 unsigned short next_target_start = 0;
611 * Given an aligned bio that extends beyond the end of a
612 * target, how many sectors must the next target handle?
614 unsigned short remaining = 0;
616 struct dm_target *ti;
617 struct queue_limits ti_limits;
621 * Check each entry in the table in turn.
623 for (i = 0; i < dm_table_get_num_targets(table); i++) {
624 ti = dm_table_get_target(table, i);
626 blk_set_stacking_limits(&ti_limits);
628 /* combine all target devices' limits */
629 if (ti->type->iterate_devices)
630 ti->type->iterate_devices(ti, dm_set_device_limits,
634 * If the remaining sectors fall entirely within this
635 * table entry are they compatible with its logical_block_size?
637 if (remaining < ti->len &&
638 remaining & ((ti_limits.logical_block_size >>
643 (unsigned short) ((next_target_start + ti->len) &
644 (device_logical_block_size_sects - 1));
645 remaining = next_target_start ?
646 device_logical_block_size_sects - next_target_start : 0;
650 DMWARN("%s: table line %u (start sect %llu len %llu) "
651 "not aligned to h/w logical block size %u",
652 dm_device_name(table->md), i,
653 (unsigned long long) ti->begin,
654 (unsigned long long) ti->len,
655 limits->logical_block_size);
662 int dm_table_add_target(struct dm_table *t, const char *type,
663 sector_t start, sector_t len, char *params)
665 int r = -EINVAL, argc;
667 struct dm_target *tgt;
670 DMERR("%s: target type %s must appear alone in table",
671 dm_device_name(t->md), t->targets->type->name);
675 BUG_ON(t->num_targets >= t->num_allocated);
677 tgt = t->targets + t->num_targets;
678 memset(tgt, 0, sizeof(*tgt));
681 DMERR("%s: zero-length target", dm_device_name(t->md));
685 tgt->type = dm_get_target_type(type);
687 DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
691 if (dm_target_needs_singleton(tgt->type)) {
692 if (t->num_targets) {
693 tgt->error = "singleton target type must appear alone in table";
699 if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) {
700 tgt->error = "target type may not be included in a read-only table";
704 if (t->immutable_target_type) {
705 if (t->immutable_target_type != tgt->type) {
706 tgt->error = "immutable target type cannot be mixed with other target types";
709 } else if (dm_target_is_immutable(tgt->type)) {
710 if (t->num_targets) {
711 tgt->error = "immutable target type cannot be mixed with other target types";
714 t->immutable_target_type = tgt->type;
717 if (dm_target_has_integrity(tgt->type))
718 t->integrity_added = 1;
723 tgt->error = "Unknown error";
726 * Does this target adjoin the previous one ?
728 if (!adjoin(t, tgt)) {
729 tgt->error = "Gap in table";
733 r = dm_split_args(&argc, &argv, params);
735 tgt->error = "couldn't split parameters (insufficient memory)";
739 r = tgt->type->ctr(tgt, argc, argv);
744 t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
746 if (!tgt->num_discard_bios && tgt->discards_supported)
747 DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
748 dm_device_name(t->md), type);
753 DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
754 dm_put_target_type(tgt->type);
759 * Target argument parsing helpers.
761 static int validate_next_arg(const struct dm_arg *arg,
762 struct dm_arg_set *arg_set,
763 unsigned *value, char **error, unsigned grouped)
765 const char *arg_str = dm_shift_arg(arg_set);
769 (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
770 (*value < arg->min) ||
771 (*value > arg->max) ||
772 (grouped && arg_set->argc < *value)) {
780 int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
781 unsigned *value, char **error)
783 return validate_next_arg(arg, arg_set, value, error, 0);
785 EXPORT_SYMBOL(dm_read_arg);
787 int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set,
788 unsigned *value, char **error)
790 return validate_next_arg(arg, arg_set, value, error, 1);
792 EXPORT_SYMBOL(dm_read_arg_group);
794 const char *dm_shift_arg(struct dm_arg_set *as)
807 EXPORT_SYMBOL(dm_shift_arg);
809 void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
811 BUG_ON(as->argc < num_args);
812 as->argc -= num_args;
813 as->argv += num_args;
815 EXPORT_SYMBOL(dm_consume_args);
817 static bool __table_type_bio_based(enum dm_queue_mode table_type)
819 return (table_type == DM_TYPE_BIO_BASED ||
820 table_type == DM_TYPE_DAX_BIO_BASED);
823 static bool __table_type_request_based(enum dm_queue_mode table_type)
825 return table_type == DM_TYPE_REQUEST_BASED;
828 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
832 EXPORT_SYMBOL_GPL(dm_table_set_type);
834 /* validate the dax capability of the target device span */
835 int device_not_dax_capable(struct dm_target *ti, struct dm_dev *dev,
836 sector_t start, sector_t len, void *data)
838 int blocksize = *(int *) data, id;
841 id = dax_read_lock();
842 rc = !dax_supported(dev->dax_dev, dev->bdev, blocksize, start, len);
848 /* Check devices support synchronous DAX */
849 static int device_not_dax_synchronous_capable(struct dm_target *ti, struct dm_dev *dev,
850 sector_t start, sector_t len, void *data)
852 return !dev->dax_dev || !dax_synchronous(dev->dax_dev);
855 bool dm_table_supports_dax(struct dm_table *t,
856 iterate_devices_callout_fn iterate_fn, int *blocksize)
858 struct dm_target *ti;
861 /* Ensure that all targets support DAX. */
862 for (i = 0; i < dm_table_get_num_targets(t); i++) {
863 ti = dm_table_get_target(t, i);
865 if (!ti->type->direct_access)
868 if (!ti->type->iterate_devices ||
869 ti->type->iterate_devices(ti, iterate_fn, blocksize))
876 static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev,
877 sector_t start, sector_t len, void *data)
879 struct block_device *bdev = dev->bdev;
880 struct request_queue *q = bdev_get_queue(bdev);
882 /* request-based cannot stack on partitions! */
883 if (bdev_is_partition(bdev))
886 return queue_is_mq(q);
889 static int dm_table_determine_type(struct dm_table *t)
892 unsigned bio_based = 0, request_based = 0, hybrid = 0;
893 struct dm_target *tgt;
894 struct list_head *devices = dm_table_get_devices(t);
895 enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
896 int page_size = PAGE_SIZE;
898 if (t->type != DM_TYPE_NONE) {
899 /* target already set the table's type */
900 if (t->type == DM_TYPE_BIO_BASED) {
901 /* possibly upgrade to a variant of bio-based */
902 goto verify_bio_based;
904 BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
905 goto verify_rq_based;
908 for (i = 0; i < t->num_targets; i++) {
909 tgt = t->targets + i;
910 if (dm_target_hybrid(tgt))
912 else if (dm_target_request_based(tgt))
917 if (bio_based && request_based) {
918 DMERR("Inconsistent table: different target types"
919 " can't be mixed up");
924 if (hybrid && !bio_based && !request_based) {
926 * The targets can work either way.
927 * Determine the type from the live device.
928 * Default to bio-based if device is new.
930 if (__table_type_request_based(live_md_type))
938 /* We must use this table as bio-based */
939 t->type = DM_TYPE_BIO_BASED;
940 if (dm_table_supports_dax(t, device_not_dax_capable, &page_size) ||
941 (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) {
942 t->type = DM_TYPE_DAX_BIO_BASED;
947 BUG_ON(!request_based); /* No targets in this table */
949 t->type = DM_TYPE_REQUEST_BASED;
953 * Request-based dm supports only tables that have a single target now.
954 * To support multiple targets, request splitting support is needed,
955 * and that needs lots of changes in the block-layer.
956 * (e.g. request completion process for partial completion.)
958 if (t->num_targets > 1) {
959 DMERR("request-based DM doesn't support multiple targets");
963 if (list_empty(devices)) {
965 struct dm_table *live_table = dm_get_live_table(t->md, &srcu_idx);
967 /* inherit live table's type */
969 t->type = live_table->type;
970 dm_put_live_table(t->md, srcu_idx);
974 tgt = dm_table_get_immutable_target(t);
976 DMERR("table load rejected: immutable target is required");
978 } else if (tgt->max_io_len) {
979 DMERR("table load rejected: immutable target that splits IO is not supported");
983 /* Non-request-stackable devices can't be used for request-based dm */
984 if (!tgt->type->iterate_devices ||
985 !tgt->type->iterate_devices(tgt, device_is_rq_stackable, NULL)) {
986 DMERR("table load rejected: including non-request-stackable devices");
993 enum dm_queue_mode dm_table_get_type(struct dm_table *t)
998 struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
1000 return t->immutable_target_type;
1003 struct dm_target *dm_table_get_immutable_target(struct dm_table *t)
1005 /* Immutable target is implicitly a singleton */
1006 if (t->num_targets > 1 ||
1007 !dm_target_is_immutable(t->targets[0].type))
1013 struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
1015 struct dm_target *ti;
1018 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1019 ti = dm_table_get_target(t, i);
1020 if (dm_target_is_wildcard(ti->type))
1027 bool dm_table_bio_based(struct dm_table *t)
1029 return __table_type_bio_based(dm_table_get_type(t));
1032 bool dm_table_request_based(struct dm_table *t)
1034 return __table_type_request_based(dm_table_get_type(t));
1037 static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
1039 enum dm_queue_mode type = dm_table_get_type(t);
1040 unsigned per_io_data_size = 0;
1041 unsigned min_pool_size = 0;
1042 struct dm_target *ti;
1045 if (unlikely(type == DM_TYPE_NONE)) {
1046 DMWARN("no table type is set, can't allocate mempools");
1050 if (__table_type_bio_based(type))
1051 for (i = 0; i < t->num_targets; i++) {
1052 ti = t->targets + i;
1053 per_io_data_size = max(per_io_data_size, ti->per_io_data_size);
1054 min_pool_size = max(min_pool_size, ti->num_flush_bios);
1057 t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported,
1058 per_io_data_size, min_pool_size);
1065 void dm_table_free_md_mempools(struct dm_table *t)
1067 dm_free_md_mempools(t->mempools);
1071 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
1076 static int setup_indexes(struct dm_table *t)
1079 unsigned int total = 0;
1082 /* allocate the space for *all* the indexes */
1083 for (i = t->depth - 2; i >= 0; i--) {
1084 t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
1085 total += t->counts[i];
1088 indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE);
1092 /* set up internal nodes, bottom-up */
1093 for (i = t->depth - 2; i >= 0; i--) {
1094 t->index[i] = indexes;
1095 indexes += (KEYS_PER_NODE * t->counts[i]);
1096 setup_btree_index(i, t);
1103 * Builds the btree to index the map.
1105 static int dm_table_build_index(struct dm_table *t)
1108 unsigned int leaf_nodes;
1110 /* how many indexes will the btree have ? */
1111 leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
1112 t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
1114 /* leaf layer has already been set up */
1115 t->counts[t->depth - 1] = leaf_nodes;
1116 t->index[t->depth - 1] = t->highs;
1119 r = setup_indexes(t);
1124 static bool integrity_profile_exists(struct gendisk *disk)
1126 return !!blk_get_integrity(disk);
1130 * Get a disk whose integrity profile reflects the table's profile.
1131 * Returns NULL if integrity support was inconsistent or unavailable.
1133 static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t)
1135 struct list_head *devices = dm_table_get_devices(t);
1136 struct dm_dev_internal *dd = NULL;
1137 struct gendisk *prev_disk = NULL, *template_disk = NULL;
1140 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1141 struct dm_target *ti = dm_table_get_target(t, i);
1142 if (!dm_target_passes_integrity(ti->type))
1146 list_for_each_entry(dd, devices, list) {
1147 template_disk = dd->dm_dev->bdev->bd_disk;
1148 if (!integrity_profile_exists(template_disk))
1150 else if (prev_disk &&
1151 blk_integrity_compare(prev_disk, template_disk) < 0)
1153 prev_disk = template_disk;
1156 return template_disk;
1160 DMWARN("%s: integrity not set: %s and %s profile mismatch",
1161 dm_device_name(t->md),
1162 prev_disk->disk_name,
1163 template_disk->disk_name);
1168 * Register the mapped device for blk_integrity support if the
1169 * underlying devices have an integrity profile. But all devices may
1170 * not have matching profiles (checking all devices isn't reliable
1171 * during table load because this table may use other DM device(s) which
1172 * must be resumed before they will have an initialized integity
1173 * profile). Consequently, stacked DM devices force a 2 stage integrity
1174 * profile validation: First pass during table load, final pass during
1177 static int dm_table_register_integrity(struct dm_table *t)
1179 struct mapped_device *md = t->md;
1180 struct gendisk *template_disk = NULL;
1182 /* If target handles integrity itself do not register it here. */
1183 if (t->integrity_added)
1186 template_disk = dm_table_get_integrity_disk(t);
1190 if (!integrity_profile_exists(dm_disk(md))) {
1191 t->integrity_supported = true;
1193 * Register integrity profile during table load; we can do
1194 * this because the final profile must match during resume.
1196 blk_integrity_register(dm_disk(md),
1197 blk_get_integrity(template_disk));
1202 * If DM device already has an initialized integrity
1203 * profile the new profile should not conflict.
1205 if (blk_integrity_compare(dm_disk(md), template_disk) < 0) {
1206 DMWARN("%s: conflict with existing integrity profile: "
1207 "%s profile mismatch",
1208 dm_device_name(t->md),
1209 template_disk->disk_name);
1213 /* Preserve existing integrity profile */
1214 t->integrity_supported = true;
1219 * Prepares the table for use by building the indices,
1220 * setting the type, and allocating mempools.
1222 int dm_table_complete(struct dm_table *t)
1226 r = dm_table_determine_type(t);
1228 DMERR("unable to determine table type");
1232 r = dm_table_build_index(t);
1234 DMERR("unable to build btrees");
1238 r = dm_table_register_integrity(t);
1240 DMERR("could not register integrity profile.");
1244 r = dm_table_alloc_md_mempools(t, t->md);
1246 DMERR("unable to allocate mempools");
1251 static DEFINE_MUTEX(_event_lock);
1252 void dm_table_event_callback(struct dm_table *t,
1253 void (*fn)(void *), void *context)
1255 mutex_lock(&_event_lock);
1257 t->event_context = context;
1258 mutex_unlock(&_event_lock);
1261 void dm_table_event(struct dm_table *t)
1263 mutex_lock(&_event_lock);
1265 t->event_fn(t->event_context);
1266 mutex_unlock(&_event_lock);
1268 EXPORT_SYMBOL(dm_table_event);
1270 inline sector_t dm_table_get_size(struct dm_table *t)
1272 return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
1274 EXPORT_SYMBOL(dm_table_get_size);
1276 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
1278 if (index >= t->num_targets)
1281 return t->targets + index;
1285 * Search the btree for the correct target.
1287 * Caller should check returned pointer for NULL
1288 * to trap I/O beyond end of device.
1290 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
1292 unsigned int l, n = 0, k = 0;
1295 if (unlikely(sector >= dm_table_get_size(t)))
1298 for (l = 0; l < t->depth; l++) {
1299 n = get_child(n, k);
1300 node = get_node(t, l, n);
1302 for (k = 0; k < KEYS_PER_NODE; k++)
1303 if (node[k] >= sector)
1307 return &t->targets[(KEYS_PER_NODE * n) + k];
1311 * type->iterate_devices() should be called when the sanity check needs to
1312 * iterate and check all underlying data devices. iterate_devices() will
1313 * iterate all underlying data devices until it encounters a non-zero return
1314 * code, returned by whether the input iterate_devices_callout_fn, or
1315 * iterate_devices() itself internally.
1317 * For some target type (e.g. dm-stripe), one call of iterate_devices() may
1318 * iterate multiple underlying devices internally, in which case a non-zero
1319 * return code returned by iterate_devices_callout_fn will stop the iteration
1322 * Cases requiring _any_ underlying device supporting some kind of attribute,
1323 * should use the iteration structure like dm_table_any_dev_attr(), or call
1324 * it directly. @func should handle semantics of positive examples, e.g.
1325 * capable of something.
1327 * Cases requiring _all_ underlying devices supporting some kind of attribute,
1328 * should use the iteration structure like dm_table_supports_nowait() or
1329 * dm_table_supports_discards(). Or introduce dm_table_all_devs_attr() that
1330 * uses an @anti_func that handle semantics of counter examples, e.g. not
1331 * capable of something. So: return !dm_table_any_dev_attr(t, anti_func, data);
1333 static bool dm_table_any_dev_attr(struct dm_table *t,
1334 iterate_devices_callout_fn func, void *data)
1336 struct dm_target *ti;
1339 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1340 ti = dm_table_get_target(t, i);
1342 if (ti->type->iterate_devices &&
1343 ti->type->iterate_devices(ti, func, data))
1350 static int count_device(struct dm_target *ti, struct dm_dev *dev,
1351 sector_t start, sector_t len, void *data)
1353 unsigned *num_devices = data;
1361 * Check whether a table has no data devices attached using each
1362 * target's iterate_devices method.
1363 * Returns false if the result is unknown because a target doesn't
1364 * support iterate_devices.
1366 bool dm_table_has_no_data_devices(struct dm_table *table)
1368 struct dm_target *ti;
1369 unsigned i, num_devices;
1371 for (i = 0; i < dm_table_get_num_targets(table); i++) {
1372 ti = dm_table_get_target(table, i);
1374 if (!ti->type->iterate_devices)
1378 ti->type->iterate_devices(ti, count_device, &num_devices);
1386 static int device_not_zoned_model(struct dm_target *ti, struct dm_dev *dev,
1387 sector_t start, sector_t len, void *data)
1389 struct request_queue *q = bdev_get_queue(dev->bdev);
1390 enum blk_zoned_model *zoned_model = data;
1392 return !q || blk_queue_zoned_model(q) != *zoned_model;
1396 * Check the device zoned model based on the target feature flag. If the target
1397 * has the DM_TARGET_ZONED_HM feature flag set, host-managed zoned devices are
1398 * also accepted but all devices must have the same zoned model. If the target
1399 * has the DM_TARGET_MIXED_ZONED_MODEL feature set, the devices can have any
1400 * zoned model with all zoned devices having the same zone size.
1402 static bool dm_table_supports_zoned_model(struct dm_table *t,
1403 enum blk_zoned_model zoned_model)
1405 struct dm_target *ti;
1408 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1409 ti = dm_table_get_target(t, i);
1411 if (dm_target_supports_zoned_hm(ti->type)) {
1412 if (!ti->type->iterate_devices ||
1413 ti->type->iterate_devices(ti, device_not_zoned_model,
1416 } else if (!dm_target_supports_mixed_zoned_model(ti->type)) {
1417 if (zoned_model == BLK_ZONED_HM)
1425 static int device_not_matches_zone_sectors(struct dm_target *ti, struct dm_dev *dev,
1426 sector_t start, sector_t len, void *data)
1428 struct request_queue *q = bdev_get_queue(dev->bdev);
1429 unsigned int *zone_sectors = data;
1431 if (!blk_queue_is_zoned(q))
1434 return !q || blk_queue_zone_sectors(q) != *zone_sectors;
1438 * Check consistency of zoned model and zone sectors across all targets. For
1439 * zone sectors, if the destination device is a zoned block device, it shall
1440 * have the specified zone_sectors.
1442 static int validate_hardware_zoned_model(struct dm_table *table,
1443 enum blk_zoned_model zoned_model,
1444 unsigned int zone_sectors)
1446 if (zoned_model == BLK_ZONED_NONE)
1449 if (!dm_table_supports_zoned_model(table, zoned_model)) {
1450 DMERR("%s: zoned model is not consistent across all devices",
1451 dm_device_name(table->md));
1455 /* Check zone size validity and compatibility */
1456 if (!zone_sectors || !is_power_of_2(zone_sectors))
1459 if (dm_table_any_dev_attr(table, device_not_matches_zone_sectors, &zone_sectors)) {
1460 DMERR("%s: zone sectors is not consistent across all zoned devices",
1461 dm_device_name(table->md));
1469 * Establish the new table's queue_limits and validate them.
1471 int dm_calculate_queue_limits(struct dm_table *table,
1472 struct queue_limits *limits)
1474 struct dm_target *ti;
1475 struct queue_limits ti_limits;
1477 enum blk_zoned_model zoned_model = BLK_ZONED_NONE;
1478 unsigned int zone_sectors = 0;
1480 blk_set_stacking_limits(limits);
1482 for (i = 0; i < dm_table_get_num_targets(table); i++) {
1483 blk_set_stacking_limits(&ti_limits);
1485 ti = dm_table_get_target(table, i);
1487 if (!ti->type->iterate_devices)
1488 goto combine_limits;
1491 * Combine queue limits of all the devices this target uses.
1493 ti->type->iterate_devices(ti, dm_set_device_limits,
1496 if (zoned_model == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
1498 * After stacking all limits, validate all devices
1499 * in table support this zoned model and zone sectors.
1501 zoned_model = ti_limits.zoned;
1502 zone_sectors = ti_limits.chunk_sectors;
1505 /* Set I/O hints portion of queue limits */
1506 if (ti->type->io_hints)
1507 ti->type->io_hints(ti, &ti_limits);
1510 * Check each device area is consistent with the target's
1511 * overall queue limits.
1513 if (ti->type->iterate_devices(ti, device_area_is_invalid,
1519 * Merge this target's queue limits into the overall limits
1522 if (blk_stack_limits(limits, &ti_limits, 0) < 0)
1523 DMWARN("%s: adding target device "
1524 "(start sect %llu len %llu) "
1525 "caused an alignment inconsistency",
1526 dm_device_name(table->md),
1527 (unsigned long long) ti->begin,
1528 (unsigned long long) ti->len);
1532 * Verify that the zoned model and zone sectors, as determined before
1533 * any .io_hints override, are the same across all devices in the table.
1534 * - this is especially relevant if .io_hints is emulating a disk-managed
1535 * zoned model (aka BLK_ZONED_NONE) on host-managed zoned block devices.
1538 if (limits->zoned != BLK_ZONED_NONE) {
1540 * ...IF the above limits stacking determined a zoned model
1541 * validate that all of the table's devices conform to it.
1543 zoned_model = limits->zoned;
1544 zone_sectors = limits->chunk_sectors;
1546 if (validate_hardware_zoned_model(table, zoned_model, zone_sectors))
1549 return validate_hardware_logical_block_alignment(table, limits);
1553 * Verify that all devices have an integrity profile that matches the
1554 * DM device's registered integrity profile. If the profiles don't
1555 * match then unregister the DM device's integrity profile.
1557 static void dm_table_verify_integrity(struct dm_table *t)
1559 struct gendisk *template_disk = NULL;
1561 if (t->integrity_added)
1564 if (t->integrity_supported) {
1566 * Verify that the original integrity profile
1567 * matches all the devices in this table.
1569 template_disk = dm_table_get_integrity_disk(t);
1570 if (template_disk &&
1571 blk_integrity_compare(dm_disk(t->md), template_disk) >= 0)
1575 if (integrity_profile_exists(dm_disk(t->md))) {
1576 DMWARN("%s: unable to establish an integrity profile",
1577 dm_device_name(t->md));
1578 blk_integrity_unregister(dm_disk(t->md));
1582 static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
1583 sector_t start, sector_t len, void *data)
1585 unsigned long flush = (unsigned long) data;
1586 struct request_queue *q = bdev_get_queue(dev->bdev);
1588 return q && (q->queue_flags & flush);
1591 static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush)
1593 struct dm_target *ti;
1597 * Require at least one underlying device to support flushes.
1598 * t->devices includes internal dm devices such as mirror logs
1599 * so we need to use iterate_devices here, which targets
1600 * supporting flushes must provide.
1602 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1603 ti = dm_table_get_target(t, i);
1605 if (!ti->num_flush_bios)
1608 if (ti->flush_supported)
1611 if (ti->type->iterate_devices &&
1612 ti->type->iterate_devices(ti, device_flush_capable, (void *) flush))
1619 static int device_dax_write_cache_enabled(struct dm_target *ti,
1620 struct dm_dev *dev, sector_t start,
1621 sector_t len, void *data)
1623 struct dax_device *dax_dev = dev->dax_dev;
1628 if (dax_write_cache_enabled(dax_dev))
1633 static int device_is_rotational(struct dm_target *ti, struct dm_dev *dev,
1634 sector_t start, sector_t len, void *data)
1636 struct request_queue *q = bdev_get_queue(dev->bdev);
1638 return q && !blk_queue_nonrot(q);
1641 static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
1642 sector_t start, sector_t len, void *data)
1644 struct request_queue *q = bdev_get_queue(dev->bdev);
1646 return q && !blk_queue_add_random(q);
1649 static int device_not_write_same_capable(struct dm_target *ti, struct dm_dev *dev,
1650 sector_t start, sector_t len, void *data)
1652 struct request_queue *q = bdev_get_queue(dev->bdev);
1654 return q && !q->limits.max_write_same_sectors;
1657 static bool dm_table_supports_write_same(struct dm_table *t)
1659 struct dm_target *ti;
1662 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1663 ti = dm_table_get_target(t, i);
1665 if (!ti->num_write_same_bios)
1668 if (!ti->type->iterate_devices ||
1669 ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
1676 static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev,
1677 sector_t start, sector_t len, void *data)
1679 struct request_queue *q = bdev_get_queue(dev->bdev);
1681 return q && !q->limits.max_write_zeroes_sectors;
1684 static bool dm_table_supports_write_zeroes(struct dm_table *t)
1686 struct dm_target *ti;
1689 while (i < dm_table_get_num_targets(t)) {
1690 ti = dm_table_get_target(t, i++);
1692 if (!ti->num_write_zeroes_bios)
1695 if (!ti->type->iterate_devices ||
1696 ti->type->iterate_devices(ti, device_not_write_zeroes_capable, NULL))
1703 static int device_not_nowait_capable(struct dm_target *ti, struct dm_dev *dev,
1704 sector_t start, sector_t len, void *data)
1706 struct request_queue *q = bdev_get_queue(dev->bdev);
1708 return q && !blk_queue_nowait(q);
1711 static bool dm_table_supports_nowait(struct dm_table *t)
1713 struct dm_target *ti;
1716 while (i < dm_table_get_num_targets(t)) {
1717 ti = dm_table_get_target(t, i++);
1719 if (!dm_target_supports_nowait(ti->type))
1722 if (!ti->type->iterate_devices ||
1723 ti->type->iterate_devices(ti, device_not_nowait_capable, NULL))
1730 static int device_not_discard_capable(struct dm_target *ti, struct dm_dev *dev,
1731 sector_t start, sector_t len, void *data)
1733 struct request_queue *q = bdev_get_queue(dev->bdev);
1735 return q && !blk_queue_discard(q);
1738 static bool dm_table_supports_discards(struct dm_table *t)
1740 struct dm_target *ti;
1743 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1744 ti = dm_table_get_target(t, i);
1746 if (!ti->num_discard_bios)
1750 * Either the target provides discard support (as implied by setting
1751 * 'discards_supported') or it relies on _all_ data devices having
1754 if (!ti->discards_supported &&
1755 (!ti->type->iterate_devices ||
1756 ti->type->iterate_devices(ti, device_not_discard_capable, NULL)))
1763 static int device_not_secure_erase_capable(struct dm_target *ti,
1764 struct dm_dev *dev, sector_t start,
1765 sector_t len, void *data)
1767 struct request_queue *q = bdev_get_queue(dev->bdev);
1769 return q && !blk_queue_secure_erase(q);
1772 static bool dm_table_supports_secure_erase(struct dm_table *t)
1774 struct dm_target *ti;
1777 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1778 ti = dm_table_get_target(t, i);
1780 if (!ti->num_secure_erase_bios)
1783 if (!ti->type->iterate_devices ||
1784 ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL))
1791 static int device_requires_stable_pages(struct dm_target *ti,
1792 struct dm_dev *dev, sector_t start,
1793 sector_t len, void *data)
1795 struct request_queue *q = bdev_get_queue(dev->bdev);
1797 return q && blk_queue_stable_writes(q);
1800 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1801 struct queue_limits *limits)
1803 bool wc = false, fua = false;
1804 int page_size = PAGE_SIZE;
1807 * Copy table's limits to the DM device's request_queue
1809 q->limits = *limits;
1811 if (dm_table_supports_nowait(t))
1812 blk_queue_flag_set(QUEUE_FLAG_NOWAIT, q);
1814 blk_queue_flag_clear(QUEUE_FLAG_NOWAIT, q);
1816 if (!dm_table_supports_discards(t)) {
1817 blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q);
1818 /* Must also clear discard limits... */
1819 q->limits.max_discard_sectors = 0;
1820 q->limits.max_hw_discard_sectors = 0;
1821 q->limits.discard_granularity = 0;
1822 q->limits.discard_alignment = 0;
1823 q->limits.discard_misaligned = 0;
1825 blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
1827 if (dm_table_supports_secure_erase(t))
1828 blk_queue_flag_set(QUEUE_FLAG_SECERASE, q);
1830 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) {
1832 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA)))
1835 blk_queue_write_cache(q, wc, fua);
1837 if (dm_table_supports_dax(t, device_not_dax_capable, &page_size)) {
1838 blk_queue_flag_set(QUEUE_FLAG_DAX, q);
1839 if (dm_table_supports_dax(t, device_not_dax_synchronous_capable, NULL))
1840 set_dax_synchronous(t->md->dax_dev);
1843 blk_queue_flag_clear(QUEUE_FLAG_DAX, q);
1845 if (dm_table_any_dev_attr(t, device_dax_write_cache_enabled, NULL))
1846 dax_write_cache(t->md->dax_dev, true);
1848 /* Ensure that all underlying devices are non-rotational. */
1849 if (dm_table_any_dev_attr(t, device_is_rotational, NULL))
1850 blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
1852 blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
1854 if (!dm_table_supports_write_same(t))
1855 q->limits.max_write_same_sectors = 0;
1856 if (!dm_table_supports_write_zeroes(t))
1857 q->limits.max_write_zeroes_sectors = 0;
1859 dm_table_verify_integrity(t);
1862 * Some devices don't use blk_integrity but still want stable pages
1863 * because they do their own checksumming.
1864 * If any underlying device requires stable pages, a table must require
1865 * them as well. Only targets that support iterate_devices are considered:
1866 * don't want error, zero, etc to require stable pages.
1868 if (dm_table_any_dev_attr(t, device_requires_stable_pages, NULL))
1869 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, q);
1871 blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, q);
1874 * Determine whether or not this queue's I/O timings contribute
1875 * to the entropy pool, Only request-based targets use this.
1876 * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
1879 if (blk_queue_add_random(q) &&
1880 dm_table_any_dev_attr(t, device_is_not_random, NULL))
1881 blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
1884 * For a zoned target, the number of zones should be updated for the
1885 * correct value to be exposed in sysfs queue/nr_zones. For a BIO based
1886 * target, this is all that is needed.
1888 #ifdef CONFIG_BLK_DEV_ZONED
1889 if (blk_queue_is_zoned(q)) {
1890 WARN_ON_ONCE(queue_is_mq(q));
1891 q->nr_zones = blkdev_nr_zones(t->md->disk);
1895 blk_queue_update_readahead(q);
1898 unsigned int dm_table_get_num_targets(struct dm_table *t)
1900 return t->num_targets;
1903 struct list_head *dm_table_get_devices(struct dm_table *t)
1908 fmode_t dm_table_get_mode(struct dm_table *t)
1912 EXPORT_SYMBOL(dm_table_get_mode);
1920 static void suspend_targets(struct dm_table *t, enum suspend_mode mode)
1922 int i = t->num_targets;
1923 struct dm_target *ti = t->targets;
1925 lockdep_assert_held(&t->md->suspend_lock);
1930 if (ti->type->presuspend)
1931 ti->type->presuspend(ti);
1933 case PRESUSPEND_UNDO:
1934 if (ti->type->presuspend_undo)
1935 ti->type->presuspend_undo(ti);
1938 if (ti->type->postsuspend)
1939 ti->type->postsuspend(ti);
1946 void dm_table_presuspend_targets(struct dm_table *t)
1951 suspend_targets(t, PRESUSPEND);
1954 void dm_table_presuspend_undo_targets(struct dm_table *t)
1959 suspend_targets(t, PRESUSPEND_UNDO);
1962 void dm_table_postsuspend_targets(struct dm_table *t)
1967 suspend_targets(t, POSTSUSPEND);
1970 int dm_table_resume_targets(struct dm_table *t)
1974 lockdep_assert_held(&t->md->suspend_lock);
1976 for (i = 0; i < t->num_targets; i++) {
1977 struct dm_target *ti = t->targets + i;
1979 if (!ti->type->preresume)
1982 r = ti->type->preresume(ti);
1984 DMERR("%s: %s: preresume failed, error = %d",
1985 dm_device_name(t->md), ti->type->name, r);
1990 for (i = 0; i < t->num_targets; i++) {
1991 struct dm_target *ti = t->targets + i;
1993 if (ti->type->resume)
1994 ti->type->resume(ti);
2000 struct mapped_device *dm_table_get_md(struct dm_table *t)
2004 EXPORT_SYMBOL(dm_table_get_md);
2006 const char *dm_table_device_name(struct dm_table *t)
2008 return dm_device_name(t->md);
2010 EXPORT_SYMBOL_GPL(dm_table_device_name);
2012 void dm_table_run_md_queue_async(struct dm_table *t)
2014 if (!dm_table_request_based(t))
2018 blk_mq_run_hw_queues(t->md->queue, true);
2020 EXPORT_SYMBOL(dm_table_run_md_queue_async);