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)
147 struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
152 INIT_LIST_HEAD(&t->devices);
155 num_targets = KEYS_PER_NODE;
157 num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
164 if (alloc_targets(t, num_targets)) {
169 t->type = DM_TYPE_NONE;
176 static void free_devices(struct list_head *devices, struct mapped_device *md)
178 struct list_head *tmp, *next;
180 list_for_each_safe(tmp, next, devices) {
181 struct dm_dev_internal *dd =
182 list_entry(tmp, struct dm_dev_internal, list);
183 DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
184 dm_device_name(md), dd->dm_dev->name);
185 dm_put_table_device(md, dd->dm_dev);
190 void dm_table_destroy(struct dm_table *t)
197 /* free the indexes */
199 vfree(t->index[t->depth - 2]);
201 /* free the targets */
202 for (i = 0; i < t->num_targets; i++) {
203 struct dm_target *tgt = t->targets + i;
208 dm_put_target_type(tgt->type);
213 /* free the device list */
214 free_devices(&t->devices, t->md);
216 dm_free_md_mempools(t->mempools);
222 * See if we've already got a device in the list.
224 static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
226 struct dm_dev_internal *dd;
228 list_for_each_entry (dd, l, list)
229 if (dd->dm_dev->bdev->bd_dev == dev)
236 * If possible, this checks an area of a destination device is invalid.
238 static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
239 sector_t start, sector_t len, void *data)
241 struct queue_limits *limits = data;
242 struct block_device *bdev = dev->bdev;
244 i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
245 unsigned short logical_block_size_sectors =
246 limits->logical_block_size >> SECTOR_SHIFT;
247 char b[BDEVNAME_SIZE];
252 if ((start >= dev_size) || (start + len > dev_size)) {
253 DMWARN("%s: %s too small for target: "
254 "start=%llu, len=%llu, dev_size=%llu",
255 dm_device_name(ti->table->md), bdevname(bdev, b),
256 (unsigned long long)start,
257 (unsigned long long)len,
258 (unsigned long long)dev_size);
263 * If the target is mapped to zoned block device(s), check
264 * that the zones are not partially mapped.
266 if (bdev_zoned_model(bdev) != BLK_ZONED_NONE) {
267 unsigned int zone_sectors = bdev_zone_sectors(bdev);
269 if (start & (zone_sectors - 1)) {
270 DMWARN("%s: start=%llu not aligned to h/w zone size %u of %s",
271 dm_device_name(ti->table->md),
272 (unsigned long long)start,
273 zone_sectors, bdevname(bdev, b));
278 * Note: The last zone of a zoned block device may be smaller
279 * than other zones. So for a target mapping the end of a
280 * zoned block device with such a zone, len would not be zone
281 * aligned. We do not allow such last smaller zone to be part
282 * of the mapping here to ensure that mappings with multiple
283 * devices do not end up with a smaller zone in the middle of
286 if (len & (zone_sectors - 1)) {
287 DMWARN("%s: len=%llu not aligned to h/w zone size %u of %s",
288 dm_device_name(ti->table->md),
289 (unsigned long long)len,
290 zone_sectors, bdevname(bdev, b));
295 if (logical_block_size_sectors <= 1)
298 if (start & (logical_block_size_sectors - 1)) {
299 DMWARN("%s: start=%llu not aligned to h/w "
300 "logical block size %u of %s",
301 dm_device_name(ti->table->md),
302 (unsigned long long)start,
303 limits->logical_block_size, bdevname(bdev, b));
307 if (len & (logical_block_size_sectors - 1)) {
308 DMWARN("%s: len=%llu not aligned to h/w "
309 "logical block size %u of %s",
310 dm_device_name(ti->table->md),
311 (unsigned long long)len,
312 limits->logical_block_size, bdevname(bdev, b));
320 * This upgrades the mode on an already open dm_dev, being
321 * careful to leave things as they were if we fail to reopen the
322 * device and not to touch the existing bdev field in case
323 * it is accessed concurrently.
325 static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
326 struct mapped_device *md)
329 struct dm_dev *old_dev, *new_dev;
331 old_dev = dd->dm_dev;
333 r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
334 dd->dm_dev->mode | new_mode, &new_dev);
338 dd->dm_dev = new_dev;
339 dm_put_table_device(md, old_dev);
345 * Convert the path to a device
347 dev_t dm_get_dev_t(const char *path)
350 struct block_device *bdev;
352 bdev = lookup_bdev(path);
354 dev = name_to_dev_t(path);
362 EXPORT_SYMBOL_GPL(dm_get_dev_t);
365 * Add a device to the list, or just increment the usage count if
366 * it's already present.
368 int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
369 struct dm_dev **result)
373 unsigned int major, minor;
375 struct dm_dev_internal *dd;
376 struct dm_table *t = ti->table;
380 if (sscanf(path, "%u:%u%c", &major, &minor, &dummy) == 2) {
381 /* Extract the major/minor numbers */
382 dev = MKDEV(major, minor);
383 if (MAJOR(dev) != major || MINOR(dev) != minor)
386 dev = dm_get_dev_t(path);
391 dd = find_device(&t->devices, dev);
393 dd = kmalloc(sizeof(*dd), GFP_KERNEL);
397 if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) {
402 refcount_set(&dd->count, 1);
403 list_add(&dd->list, &t->devices);
406 } else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
407 r = upgrade_mode(dd, mode, t->md);
411 refcount_inc(&dd->count);
413 *result = dd->dm_dev;
416 EXPORT_SYMBOL(dm_get_device);
418 static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
419 sector_t start, sector_t len, void *data)
421 struct queue_limits *limits = data;
422 struct block_device *bdev = dev->bdev;
423 struct request_queue *q = bdev_get_queue(bdev);
424 char b[BDEVNAME_SIZE];
427 DMWARN("%s: Cannot set limits for nonexistent device %s",
428 dm_device_name(ti->table->md), bdevname(bdev, b));
432 if (blk_stack_limits(limits, &q->limits,
433 get_start_sect(bdev) + start) < 0)
434 DMWARN("%s: adding target device %s caused an alignment inconsistency: "
435 "physical_block_size=%u, logical_block_size=%u, "
436 "alignment_offset=%u, start=%llu",
437 dm_device_name(ti->table->md), bdevname(bdev, b),
438 q->limits.physical_block_size,
439 q->limits.logical_block_size,
440 q->limits.alignment_offset,
441 (unsigned long long) start << SECTOR_SHIFT);
446 * Decrement a device's use count and remove it if necessary.
448 void dm_put_device(struct dm_target *ti, struct dm_dev *d)
451 struct list_head *devices = &ti->table->devices;
452 struct dm_dev_internal *dd;
454 list_for_each_entry(dd, devices, list) {
455 if (dd->dm_dev == d) {
461 DMWARN("%s: device %s not in table devices list",
462 dm_device_name(ti->table->md), d->name);
465 if (refcount_dec_and_test(&dd->count)) {
466 dm_put_table_device(ti->table->md, d);
471 EXPORT_SYMBOL(dm_put_device);
474 * Checks to see if the target joins onto the end of the table.
476 static int adjoin(struct dm_table *table, struct dm_target *ti)
478 struct dm_target *prev;
480 if (!table->num_targets)
483 prev = &table->targets[table->num_targets - 1];
484 return (ti->begin == (prev->begin + prev->len));
488 * Used to dynamically allocate the arg array.
490 * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
491 * process messages even if some device is suspended. These messages have a
492 * small fixed number of arguments.
494 * On the other hand, dm-switch needs to process bulk data using messages and
495 * excessive use of GFP_NOIO could cause trouble.
497 static char **realloc_argv(unsigned *size, char **old_argv)
504 new_size = *size * 2;
510 argv = kmalloc_array(new_size, sizeof(*argv), gfp);
511 if (argv && old_argv) {
512 memcpy(argv, old_argv, *size * sizeof(*argv));
521 * Destructively splits up the argument list to pass to ctr.
523 int dm_split_args(int *argc, char ***argvp, char *input)
525 char *start, *end = input, *out, **argv = NULL;
526 unsigned array_size = 0;
535 argv = realloc_argv(&array_size, argv);
540 /* Skip whitespace */
541 start = skip_spaces(end);
544 break; /* success, we hit the end */
546 /* 'out' is used to remove any back-quotes */
549 /* Everything apart from '\0' can be quoted */
550 if (*end == '\\' && *(end + 1)) {
557 break; /* end of token */
562 /* have we already filled the array ? */
563 if ((*argc + 1) > array_size) {
564 argv = realloc_argv(&array_size, argv);
569 /* we know this is whitespace */
573 /* terminate the string and put it in the array */
584 * Impose necessary and sufficient conditions on a devices's table such
585 * that any incoming bio which respects its logical_block_size can be
586 * processed successfully. If it falls across the boundary between
587 * two or more targets, the size of each piece it gets split into must
588 * be compatible with the logical_block_size of the target processing it.
590 static int validate_hardware_logical_block_alignment(struct dm_table *table,
591 struct queue_limits *limits)
594 * This function uses arithmetic modulo the logical_block_size
595 * (in units of 512-byte sectors).
597 unsigned short device_logical_block_size_sects =
598 limits->logical_block_size >> SECTOR_SHIFT;
601 * Offset of the start of the next table entry, mod logical_block_size.
603 unsigned short next_target_start = 0;
606 * Given an aligned bio that extends beyond the end of a
607 * target, how many sectors must the next target handle?
609 unsigned short remaining = 0;
611 struct dm_target *ti;
612 struct queue_limits ti_limits;
616 * Check each entry in the table in turn.
618 for (i = 0; i < dm_table_get_num_targets(table); i++) {
619 ti = dm_table_get_target(table, i);
621 blk_set_stacking_limits(&ti_limits);
623 /* combine all target devices' limits */
624 if (ti->type->iterate_devices)
625 ti->type->iterate_devices(ti, dm_set_device_limits,
629 * If the remaining sectors fall entirely within this
630 * table entry are they compatible with its logical_block_size?
632 if (remaining < ti->len &&
633 remaining & ((ti_limits.logical_block_size >>
638 (unsigned short) ((next_target_start + ti->len) &
639 (device_logical_block_size_sects - 1));
640 remaining = next_target_start ?
641 device_logical_block_size_sects - next_target_start : 0;
645 DMWARN("%s: table line %u (start sect %llu len %llu) "
646 "not aligned to h/w logical block size %u",
647 dm_device_name(table->md), i,
648 (unsigned long long) ti->begin,
649 (unsigned long long) ti->len,
650 limits->logical_block_size);
657 int dm_table_add_target(struct dm_table *t, const char *type,
658 sector_t start, sector_t len, char *params)
660 int r = -EINVAL, argc;
662 struct dm_target *tgt;
665 DMERR("%s: target type %s must appear alone in table",
666 dm_device_name(t->md), t->targets->type->name);
670 BUG_ON(t->num_targets >= t->num_allocated);
672 tgt = t->targets + t->num_targets;
673 memset(tgt, 0, sizeof(*tgt));
676 DMERR("%s: zero-length target", dm_device_name(t->md));
680 tgt->type = dm_get_target_type(type);
682 DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
686 if (dm_target_needs_singleton(tgt->type)) {
687 if (t->num_targets) {
688 tgt->error = "singleton target type must appear alone in table";
694 if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) {
695 tgt->error = "target type may not be included in a read-only table";
699 if (t->immutable_target_type) {
700 if (t->immutable_target_type != tgt->type) {
701 tgt->error = "immutable target type cannot be mixed with other target types";
704 } else if (dm_target_is_immutable(tgt->type)) {
705 if (t->num_targets) {
706 tgt->error = "immutable target type cannot be mixed with other target types";
709 t->immutable_target_type = tgt->type;
712 if (dm_target_has_integrity(tgt->type))
713 t->integrity_added = 1;
718 tgt->error = "Unknown error";
721 * Does this target adjoin the previous one ?
723 if (!adjoin(t, tgt)) {
724 tgt->error = "Gap in table";
728 r = dm_split_args(&argc, &argv, params);
730 tgt->error = "couldn't split parameters (insufficient memory)";
734 r = tgt->type->ctr(tgt, argc, argv);
739 t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
741 if (!tgt->num_discard_bios && tgt->discards_supported)
742 DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
743 dm_device_name(t->md), type);
748 DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
749 dm_put_target_type(tgt->type);
754 * Target argument parsing helpers.
756 static int validate_next_arg(const struct dm_arg *arg,
757 struct dm_arg_set *arg_set,
758 unsigned *value, char **error, unsigned grouped)
760 const char *arg_str = dm_shift_arg(arg_set);
764 (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
765 (*value < arg->min) ||
766 (*value > arg->max) ||
767 (grouped && arg_set->argc < *value)) {
775 int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
776 unsigned *value, char **error)
778 return validate_next_arg(arg, arg_set, value, error, 0);
780 EXPORT_SYMBOL(dm_read_arg);
782 int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set,
783 unsigned *value, char **error)
785 return validate_next_arg(arg, arg_set, value, error, 1);
787 EXPORT_SYMBOL(dm_read_arg_group);
789 const char *dm_shift_arg(struct dm_arg_set *as)
802 EXPORT_SYMBOL(dm_shift_arg);
804 void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
806 BUG_ON(as->argc < num_args);
807 as->argc -= num_args;
808 as->argv += num_args;
810 EXPORT_SYMBOL(dm_consume_args);
812 static bool __table_type_bio_based(enum dm_queue_mode table_type)
814 return (table_type == DM_TYPE_BIO_BASED ||
815 table_type == DM_TYPE_DAX_BIO_BASED);
818 static bool __table_type_request_based(enum dm_queue_mode table_type)
820 return table_type == DM_TYPE_REQUEST_BASED;
823 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
827 EXPORT_SYMBOL_GPL(dm_table_set_type);
829 /* validate the dax capability of the target device span */
830 int device_not_dax_capable(struct dm_target *ti, struct dm_dev *dev,
831 sector_t start, sector_t len, void *data)
833 int blocksize = *(int *) data, id;
836 id = dax_read_lock();
837 rc = !dax_supported(dev->dax_dev, dev->bdev, blocksize, start, len);
843 /* Check devices support synchronous DAX */
844 static int device_not_dax_synchronous_capable(struct dm_target *ti, struct dm_dev *dev,
845 sector_t start, sector_t len, void *data)
847 return !dev->dax_dev || !dax_synchronous(dev->dax_dev);
850 bool dm_table_supports_dax(struct dm_table *t,
851 iterate_devices_callout_fn iterate_fn, int *blocksize)
853 struct dm_target *ti;
856 /* Ensure that all targets support DAX. */
857 for (i = 0; i < dm_table_get_num_targets(t); i++) {
858 ti = dm_table_get_target(t, i);
860 if (!ti->type->direct_access)
863 if (!ti->type->iterate_devices ||
864 ti->type->iterate_devices(ti, iterate_fn, blocksize))
871 static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev,
872 sector_t start, sector_t len, void *data)
874 struct block_device *bdev = dev->bdev;
875 struct request_queue *q = bdev_get_queue(bdev);
877 /* request-based cannot stack on partitions! */
878 if (bdev_is_partition(bdev))
881 return queue_is_mq(q);
884 static int dm_table_determine_type(struct dm_table *t)
887 unsigned bio_based = 0, request_based = 0, hybrid = 0;
888 struct dm_target *tgt;
889 struct list_head *devices = dm_table_get_devices(t);
890 enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
891 int page_size = PAGE_SIZE;
893 if (t->type != DM_TYPE_NONE) {
894 /* target already set the table's type */
895 if (t->type == DM_TYPE_BIO_BASED) {
896 /* possibly upgrade to a variant of bio-based */
897 goto verify_bio_based;
899 BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
900 goto verify_rq_based;
903 for (i = 0; i < t->num_targets; i++) {
904 tgt = t->targets + i;
905 if (dm_target_hybrid(tgt))
907 else if (dm_target_request_based(tgt))
912 if (bio_based && request_based) {
913 DMERR("Inconsistent table: different target types"
914 " can't be mixed up");
919 if (hybrid && !bio_based && !request_based) {
921 * The targets can work either way.
922 * Determine the type from the live device.
923 * Default to bio-based if device is new.
925 if (__table_type_request_based(live_md_type))
933 /* We must use this table as bio-based */
934 t->type = DM_TYPE_BIO_BASED;
935 if (dm_table_supports_dax(t, device_not_dax_capable, &page_size) ||
936 (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) {
937 t->type = DM_TYPE_DAX_BIO_BASED;
942 BUG_ON(!request_based); /* No targets in this table */
944 t->type = DM_TYPE_REQUEST_BASED;
948 * Request-based dm supports only tables that have a single target now.
949 * To support multiple targets, request splitting support is needed,
950 * and that needs lots of changes in the block-layer.
951 * (e.g. request completion process for partial completion.)
953 if (t->num_targets > 1) {
954 DMERR("request-based DM doesn't support multiple targets");
958 if (list_empty(devices)) {
960 struct dm_table *live_table = dm_get_live_table(t->md, &srcu_idx);
962 /* inherit live table's type */
964 t->type = live_table->type;
965 dm_put_live_table(t->md, srcu_idx);
969 tgt = dm_table_get_immutable_target(t);
971 DMERR("table load rejected: immutable target is required");
973 } else if (tgt->max_io_len) {
974 DMERR("table load rejected: immutable target that splits IO is not supported");
978 /* Non-request-stackable devices can't be used for request-based dm */
979 if (!tgt->type->iterate_devices ||
980 !tgt->type->iterate_devices(tgt, device_is_rq_stackable, NULL)) {
981 DMERR("table load rejected: including non-request-stackable devices");
988 enum dm_queue_mode dm_table_get_type(struct dm_table *t)
993 struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
995 return t->immutable_target_type;
998 struct dm_target *dm_table_get_immutable_target(struct dm_table *t)
1000 /* Immutable target is implicitly a singleton */
1001 if (t->num_targets > 1 ||
1002 !dm_target_is_immutable(t->targets[0].type))
1008 struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
1010 struct dm_target *ti;
1013 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1014 ti = dm_table_get_target(t, i);
1015 if (dm_target_is_wildcard(ti->type))
1022 bool dm_table_bio_based(struct dm_table *t)
1024 return __table_type_bio_based(dm_table_get_type(t));
1027 bool dm_table_request_based(struct dm_table *t)
1029 return __table_type_request_based(dm_table_get_type(t));
1032 static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
1034 enum dm_queue_mode type = dm_table_get_type(t);
1035 unsigned per_io_data_size = 0;
1036 unsigned min_pool_size = 0;
1037 struct dm_target *ti;
1040 if (unlikely(type == DM_TYPE_NONE)) {
1041 DMWARN("no table type is set, can't allocate mempools");
1045 if (__table_type_bio_based(type))
1046 for (i = 0; i < t->num_targets; i++) {
1047 ti = t->targets + i;
1048 per_io_data_size = max(per_io_data_size, ti->per_io_data_size);
1049 min_pool_size = max(min_pool_size, ti->num_flush_bios);
1052 t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported,
1053 per_io_data_size, min_pool_size);
1060 void dm_table_free_md_mempools(struct dm_table *t)
1062 dm_free_md_mempools(t->mempools);
1066 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
1071 static int setup_indexes(struct dm_table *t)
1074 unsigned int total = 0;
1077 /* allocate the space for *all* the indexes */
1078 for (i = t->depth - 2; i >= 0; i--) {
1079 t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
1080 total += t->counts[i];
1083 indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE);
1087 /* set up internal nodes, bottom-up */
1088 for (i = t->depth - 2; i >= 0; i--) {
1089 t->index[i] = indexes;
1090 indexes += (KEYS_PER_NODE * t->counts[i]);
1091 setup_btree_index(i, t);
1098 * Builds the btree to index the map.
1100 static int dm_table_build_index(struct dm_table *t)
1103 unsigned int leaf_nodes;
1105 /* how many indexes will the btree have ? */
1106 leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
1107 t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
1109 /* leaf layer has already been set up */
1110 t->counts[t->depth - 1] = leaf_nodes;
1111 t->index[t->depth - 1] = t->highs;
1114 r = setup_indexes(t);
1119 static bool integrity_profile_exists(struct gendisk *disk)
1121 return !!blk_get_integrity(disk);
1125 * Get a disk whose integrity profile reflects the table's profile.
1126 * Returns NULL if integrity support was inconsistent or unavailable.
1128 static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t)
1130 struct list_head *devices = dm_table_get_devices(t);
1131 struct dm_dev_internal *dd = NULL;
1132 struct gendisk *prev_disk = NULL, *template_disk = NULL;
1135 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1136 struct dm_target *ti = dm_table_get_target(t, i);
1137 if (!dm_target_passes_integrity(ti->type))
1141 list_for_each_entry(dd, devices, list) {
1142 template_disk = dd->dm_dev->bdev->bd_disk;
1143 if (!integrity_profile_exists(template_disk))
1145 else if (prev_disk &&
1146 blk_integrity_compare(prev_disk, template_disk) < 0)
1148 prev_disk = template_disk;
1151 return template_disk;
1155 DMWARN("%s: integrity not set: %s and %s profile mismatch",
1156 dm_device_name(t->md),
1157 prev_disk->disk_name,
1158 template_disk->disk_name);
1163 * Register the mapped device for blk_integrity support if the
1164 * underlying devices have an integrity profile. But all devices may
1165 * not have matching profiles (checking all devices isn't reliable
1166 * during table load because this table may use other DM device(s) which
1167 * must be resumed before they will have an initialized integity
1168 * profile). Consequently, stacked DM devices force a 2 stage integrity
1169 * profile validation: First pass during table load, final pass during
1172 static int dm_table_register_integrity(struct dm_table *t)
1174 struct mapped_device *md = t->md;
1175 struct gendisk *template_disk = NULL;
1177 /* If target handles integrity itself do not register it here. */
1178 if (t->integrity_added)
1181 template_disk = dm_table_get_integrity_disk(t);
1185 if (!integrity_profile_exists(dm_disk(md))) {
1186 t->integrity_supported = true;
1188 * Register integrity profile during table load; we can do
1189 * this because the final profile must match during resume.
1191 blk_integrity_register(dm_disk(md),
1192 blk_get_integrity(template_disk));
1197 * If DM device already has an initialized integrity
1198 * profile the new profile should not conflict.
1200 if (blk_integrity_compare(dm_disk(md), template_disk) < 0) {
1201 DMWARN("%s: conflict with existing integrity profile: "
1202 "%s profile mismatch",
1203 dm_device_name(t->md),
1204 template_disk->disk_name);
1208 /* Preserve existing integrity profile */
1209 t->integrity_supported = true;
1214 * Prepares the table for use by building the indices,
1215 * setting the type, and allocating mempools.
1217 int dm_table_complete(struct dm_table *t)
1221 r = dm_table_determine_type(t);
1223 DMERR("unable to determine table type");
1227 r = dm_table_build_index(t);
1229 DMERR("unable to build btrees");
1233 r = dm_table_register_integrity(t);
1235 DMERR("could not register integrity profile.");
1239 r = dm_table_alloc_md_mempools(t, t->md);
1241 DMERR("unable to allocate mempools");
1246 static DEFINE_MUTEX(_event_lock);
1247 void dm_table_event_callback(struct dm_table *t,
1248 void (*fn)(void *), void *context)
1250 mutex_lock(&_event_lock);
1252 t->event_context = context;
1253 mutex_unlock(&_event_lock);
1256 void dm_table_event(struct dm_table *t)
1258 mutex_lock(&_event_lock);
1260 t->event_fn(t->event_context);
1261 mutex_unlock(&_event_lock);
1263 EXPORT_SYMBOL(dm_table_event);
1265 inline sector_t dm_table_get_size(struct dm_table *t)
1267 return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
1269 EXPORT_SYMBOL(dm_table_get_size);
1271 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
1273 if (index >= t->num_targets)
1276 return t->targets + index;
1280 * Search the btree for the correct target.
1282 * Caller should check returned pointer for NULL
1283 * to trap I/O beyond end of device.
1285 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
1287 unsigned int l, n = 0, k = 0;
1290 if (unlikely(sector >= dm_table_get_size(t)))
1293 for (l = 0; l < t->depth; l++) {
1294 n = get_child(n, k);
1295 node = get_node(t, l, n);
1297 for (k = 0; k < KEYS_PER_NODE; k++)
1298 if (node[k] >= sector)
1302 return &t->targets[(KEYS_PER_NODE * n) + k];
1306 * type->iterate_devices() should be called when the sanity check needs to
1307 * iterate and check all underlying data devices. iterate_devices() will
1308 * iterate all underlying data devices until it encounters a non-zero return
1309 * code, returned by whether the input iterate_devices_callout_fn, or
1310 * iterate_devices() itself internally.
1312 * For some target type (e.g. dm-stripe), one call of iterate_devices() may
1313 * iterate multiple underlying devices internally, in which case a non-zero
1314 * return code returned by iterate_devices_callout_fn will stop the iteration
1317 * Cases requiring _any_ underlying device supporting some kind of attribute,
1318 * should use the iteration structure like dm_table_any_dev_attr(), or call
1319 * it directly. @func should handle semantics of positive examples, e.g.
1320 * capable of something.
1322 * Cases requiring _all_ underlying devices supporting some kind of attribute,
1323 * should use the iteration structure like dm_table_supports_nowait() or
1324 * dm_table_supports_discards(). Or introduce dm_table_all_devs_attr() that
1325 * uses an @anti_func that handle semantics of counter examples, e.g. not
1326 * capable of something. So: return !dm_table_any_dev_attr(t, anti_func, data);
1328 static bool dm_table_any_dev_attr(struct dm_table *t,
1329 iterate_devices_callout_fn func, void *data)
1331 struct dm_target *ti;
1334 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1335 ti = dm_table_get_target(t, i);
1337 if (ti->type->iterate_devices &&
1338 ti->type->iterate_devices(ti, func, data))
1345 static int count_device(struct dm_target *ti, struct dm_dev *dev,
1346 sector_t start, sector_t len, void *data)
1348 unsigned *num_devices = data;
1356 * Check whether a table has no data devices attached using each
1357 * target's iterate_devices method.
1358 * Returns false if the result is unknown because a target doesn't
1359 * support iterate_devices.
1361 bool dm_table_has_no_data_devices(struct dm_table *table)
1363 struct dm_target *ti;
1364 unsigned i, num_devices;
1366 for (i = 0; i < dm_table_get_num_targets(table); i++) {
1367 ti = dm_table_get_target(table, i);
1369 if (!ti->type->iterate_devices)
1373 ti->type->iterate_devices(ti, count_device, &num_devices);
1381 static int device_not_zoned_model(struct dm_target *ti, struct dm_dev *dev,
1382 sector_t start, sector_t len, void *data)
1384 struct request_queue *q = bdev_get_queue(dev->bdev);
1385 enum blk_zoned_model *zoned_model = data;
1387 return !q || blk_queue_zoned_model(q) != *zoned_model;
1391 * Check the device zoned model based on the target feature flag. If the target
1392 * has the DM_TARGET_ZONED_HM feature flag set, host-managed zoned devices are
1393 * also accepted but all devices must have the same zoned model. If the target
1394 * has the DM_TARGET_MIXED_ZONED_MODEL feature set, the devices can have any
1395 * zoned model with all zoned devices having the same zone size.
1397 static bool dm_table_supports_zoned_model(struct dm_table *t,
1398 enum blk_zoned_model zoned_model)
1400 struct dm_target *ti;
1403 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1404 ti = dm_table_get_target(t, i);
1406 if (dm_target_supports_zoned_hm(ti->type)) {
1407 if (!ti->type->iterate_devices ||
1408 ti->type->iterate_devices(ti, device_not_zoned_model,
1411 } else if (!dm_target_supports_mixed_zoned_model(ti->type)) {
1412 if (zoned_model == BLK_ZONED_HM)
1420 static int device_not_matches_zone_sectors(struct dm_target *ti, struct dm_dev *dev,
1421 sector_t start, sector_t len, void *data)
1423 struct request_queue *q = bdev_get_queue(dev->bdev);
1424 unsigned int *zone_sectors = data;
1426 if (!blk_queue_is_zoned(q))
1429 return !q || blk_queue_zone_sectors(q) != *zone_sectors;
1433 * Check consistency of zoned model and zone sectors across all targets. For
1434 * zone sectors, if the destination device is a zoned block device, it shall
1435 * have the specified zone_sectors.
1437 static int validate_hardware_zoned_model(struct dm_table *table,
1438 enum blk_zoned_model zoned_model,
1439 unsigned int zone_sectors)
1441 if (zoned_model == BLK_ZONED_NONE)
1444 if (!dm_table_supports_zoned_model(table, zoned_model)) {
1445 DMERR("%s: zoned model is not consistent across all devices",
1446 dm_device_name(table->md));
1450 /* Check zone size validity and compatibility */
1451 if (!zone_sectors || !is_power_of_2(zone_sectors))
1454 if (dm_table_any_dev_attr(table, device_not_matches_zone_sectors, &zone_sectors)) {
1455 DMERR("%s: zone sectors is not consistent across all zoned devices",
1456 dm_device_name(table->md));
1464 * Establish the new table's queue_limits and validate them.
1466 int dm_calculate_queue_limits(struct dm_table *table,
1467 struct queue_limits *limits)
1469 struct dm_target *ti;
1470 struct queue_limits ti_limits;
1472 enum blk_zoned_model zoned_model = BLK_ZONED_NONE;
1473 unsigned int zone_sectors = 0;
1475 blk_set_stacking_limits(limits);
1477 for (i = 0; i < dm_table_get_num_targets(table); i++) {
1478 blk_set_stacking_limits(&ti_limits);
1480 ti = dm_table_get_target(table, i);
1482 if (!ti->type->iterate_devices)
1483 goto combine_limits;
1486 * Combine queue limits of all the devices this target uses.
1488 ti->type->iterate_devices(ti, dm_set_device_limits,
1491 if (zoned_model == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
1493 * After stacking all limits, validate all devices
1494 * in table support this zoned model and zone sectors.
1496 zoned_model = ti_limits.zoned;
1497 zone_sectors = ti_limits.chunk_sectors;
1500 /* Set I/O hints portion of queue limits */
1501 if (ti->type->io_hints)
1502 ti->type->io_hints(ti, &ti_limits);
1505 * Check each device area is consistent with the target's
1506 * overall queue limits.
1508 if (ti->type->iterate_devices(ti, device_area_is_invalid,
1514 * Merge this target's queue limits into the overall limits
1517 if (blk_stack_limits(limits, &ti_limits, 0) < 0)
1518 DMWARN("%s: adding target device "
1519 "(start sect %llu len %llu) "
1520 "caused an alignment inconsistency",
1521 dm_device_name(table->md),
1522 (unsigned long long) ti->begin,
1523 (unsigned long long) ti->len);
1527 * Verify that the zoned model and zone sectors, as determined before
1528 * any .io_hints override, are the same across all devices in the table.
1529 * - this is especially relevant if .io_hints is emulating a disk-managed
1530 * zoned model (aka BLK_ZONED_NONE) on host-managed zoned block devices.
1533 if (limits->zoned != BLK_ZONED_NONE) {
1535 * ...IF the above limits stacking determined a zoned model
1536 * validate that all of the table's devices conform to it.
1538 zoned_model = limits->zoned;
1539 zone_sectors = limits->chunk_sectors;
1541 if (validate_hardware_zoned_model(table, zoned_model, zone_sectors))
1544 return validate_hardware_logical_block_alignment(table, limits);
1548 * Verify that all devices have an integrity profile that matches the
1549 * DM device's registered integrity profile. If the profiles don't
1550 * match then unregister the DM device's integrity profile.
1552 static void dm_table_verify_integrity(struct dm_table *t)
1554 struct gendisk *template_disk = NULL;
1556 if (t->integrity_added)
1559 if (t->integrity_supported) {
1561 * Verify that the original integrity profile
1562 * matches all the devices in this table.
1564 template_disk = dm_table_get_integrity_disk(t);
1565 if (template_disk &&
1566 blk_integrity_compare(dm_disk(t->md), template_disk) >= 0)
1570 if (integrity_profile_exists(dm_disk(t->md))) {
1571 DMWARN("%s: unable to establish an integrity profile",
1572 dm_device_name(t->md));
1573 blk_integrity_unregister(dm_disk(t->md));
1577 static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
1578 sector_t start, sector_t len, void *data)
1580 unsigned long flush = (unsigned long) data;
1581 struct request_queue *q = bdev_get_queue(dev->bdev);
1583 return q && (q->queue_flags & flush);
1586 static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush)
1588 struct dm_target *ti;
1592 * Require at least one underlying device to support flushes.
1593 * t->devices includes internal dm devices such as mirror logs
1594 * so we need to use iterate_devices here, which targets
1595 * supporting flushes must provide.
1597 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1598 ti = dm_table_get_target(t, i);
1600 if (!ti->num_flush_bios)
1603 if (ti->flush_supported)
1606 if (ti->type->iterate_devices &&
1607 ti->type->iterate_devices(ti, device_flush_capable, (void *) flush))
1614 static int device_dax_write_cache_enabled(struct dm_target *ti,
1615 struct dm_dev *dev, sector_t start,
1616 sector_t len, void *data)
1618 struct dax_device *dax_dev = dev->dax_dev;
1623 if (dax_write_cache_enabled(dax_dev))
1628 static int device_is_rotational(struct dm_target *ti, struct dm_dev *dev,
1629 sector_t start, sector_t len, void *data)
1631 struct request_queue *q = bdev_get_queue(dev->bdev);
1633 return q && !blk_queue_nonrot(q);
1636 static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
1637 sector_t start, sector_t len, void *data)
1639 struct request_queue *q = bdev_get_queue(dev->bdev);
1641 return q && !blk_queue_add_random(q);
1644 static int device_not_write_same_capable(struct dm_target *ti, struct dm_dev *dev,
1645 sector_t start, sector_t len, void *data)
1647 struct request_queue *q = bdev_get_queue(dev->bdev);
1649 return q && !q->limits.max_write_same_sectors;
1652 static bool dm_table_supports_write_same(struct dm_table *t)
1654 struct dm_target *ti;
1657 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1658 ti = dm_table_get_target(t, i);
1660 if (!ti->num_write_same_bios)
1663 if (!ti->type->iterate_devices ||
1664 ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
1671 static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev,
1672 sector_t start, sector_t len, void *data)
1674 struct request_queue *q = bdev_get_queue(dev->bdev);
1676 return q && !q->limits.max_write_zeroes_sectors;
1679 static bool dm_table_supports_write_zeroes(struct dm_table *t)
1681 struct dm_target *ti;
1684 while (i < dm_table_get_num_targets(t)) {
1685 ti = dm_table_get_target(t, i++);
1687 if (!ti->num_write_zeroes_bios)
1690 if (!ti->type->iterate_devices ||
1691 ti->type->iterate_devices(ti, device_not_write_zeroes_capable, NULL))
1698 static int device_not_nowait_capable(struct dm_target *ti, struct dm_dev *dev,
1699 sector_t start, sector_t len, void *data)
1701 struct request_queue *q = bdev_get_queue(dev->bdev);
1703 return q && !blk_queue_nowait(q);
1706 static bool dm_table_supports_nowait(struct dm_table *t)
1708 struct dm_target *ti;
1711 while (i < dm_table_get_num_targets(t)) {
1712 ti = dm_table_get_target(t, i++);
1714 if (!dm_target_supports_nowait(ti->type))
1717 if (!ti->type->iterate_devices ||
1718 ti->type->iterate_devices(ti, device_not_nowait_capable, NULL))
1725 static int device_not_discard_capable(struct dm_target *ti, struct dm_dev *dev,
1726 sector_t start, sector_t len, void *data)
1728 struct request_queue *q = bdev_get_queue(dev->bdev);
1730 return q && !blk_queue_discard(q);
1733 static bool dm_table_supports_discards(struct dm_table *t)
1735 struct dm_target *ti;
1738 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1739 ti = dm_table_get_target(t, i);
1741 if (!ti->num_discard_bios)
1745 * Either the target provides discard support (as implied by setting
1746 * 'discards_supported') or it relies on _all_ data devices having
1749 if (!ti->discards_supported &&
1750 (!ti->type->iterate_devices ||
1751 ti->type->iterate_devices(ti, device_not_discard_capable, NULL)))
1758 static int device_not_secure_erase_capable(struct dm_target *ti,
1759 struct dm_dev *dev, sector_t start,
1760 sector_t len, void *data)
1762 struct request_queue *q = bdev_get_queue(dev->bdev);
1764 return q && !blk_queue_secure_erase(q);
1767 static bool dm_table_supports_secure_erase(struct dm_table *t)
1769 struct dm_target *ti;
1772 for (i = 0; i < dm_table_get_num_targets(t); i++) {
1773 ti = dm_table_get_target(t, i);
1775 if (!ti->num_secure_erase_bios)
1778 if (!ti->type->iterate_devices ||
1779 ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL))
1786 static int device_requires_stable_pages(struct dm_target *ti,
1787 struct dm_dev *dev, sector_t start,
1788 sector_t len, void *data)
1790 struct request_queue *q = bdev_get_queue(dev->bdev);
1792 return q && blk_queue_stable_writes(q);
1795 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1796 struct queue_limits *limits)
1798 bool wc = false, fua = false;
1799 int page_size = PAGE_SIZE;
1802 * Copy table's limits to the DM device's request_queue
1804 q->limits = *limits;
1806 if (dm_table_supports_nowait(t))
1807 blk_queue_flag_set(QUEUE_FLAG_NOWAIT, q);
1809 blk_queue_flag_clear(QUEUE_FLAG_NOWAIT, q);
1811 if (!dm_table_supports_discards(t)) {
1812 blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q);
1813 /* Must also clear discard limits... */
1814 q->limits.max_discard_sectors = 0;
1815 q->limits.max_hw_discard_sectors = 0;
1816 q->limits.discard_granularity = 0;
1817 q->limits.discard_alignment = 0;
1818 q->limits.discard_misaligned = 0;
1820 blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
1822 if (dm_table_supports_secure_erase(t))
1823 blk_queue_flag_set(QUEUE_FLAG_SECERASE, q);
1825 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) {
1827 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA)))
1830 blk_queue_write_cache(q, wc, fua);
1832 if (dm_table_supports_dax(t, device_not_dax_capable, &page_size)) {
1833 blk_queue_flag_set(QUEUE_FLAG_DAX, q);
1834 if (dm_table_supports_dax(t, device_not_dax_synchronous_capable, NULL))
1835 set_dax_synchronous(t->md->dax_dev);
1838 blk_queue_flag_clear(QUEUE_FLAG_DAX, q);
1840 if (dm_table_any_dev_attr(t, device_dax_write_cache_enabled, NULL))
1841 dax_write_cache(t->md->dax_dev, true);
1843 /* Ensure that all underlying devices are non-rotational. */
1844 if (dm_table_any_dev_attr(t, device_is_rotational, NULL))
1845 blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
1847 blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
1849 if (!dm_table_supports_write_same(t))
1850 q->limits.max_write_same_sectors = 0;
1851 if (!dm_table_supports_write_zeroes(t))
1852 q->limits.max_write_zeroes_sectors = 0;
1854 dm_table_verify_integrity(t);
1857 * Some devices don't use blk_integrity but still want stable pages
1858 * because they do their own checksumming.
1859 * If any underlying device requires stable pages, a table must require
1860 * them as well. Only targets that support iterate_devices are considered:
1861 * don't want error, zero, etc to require stable pages.
1863 if (dm_table_any_dev_attr(t, device_requires_stable_pages, NULL))
1864 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, q);
1866 blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, q);
1869 * Determine whether or not this queue's I/O timings contribute
1870 * to the entropy pool, Only request-based targets use this.
1871 * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
1874 if (blk_queue_add_random(q) &&
1875 dm_table_any_dev_attr(t, device_is_not_random, NULL))
1876 blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
1879 * For a zoned target, the number of zones should be updated for the
1880 * correct value to be exposed in sysfs queue/nr_zones. For a BIO based
1881 * target, this is all that is needed.
1883 #ifdef CONFIG_BLK_DEV_ZONED
1884 if (blk_queue_is_zoned(q)) {
1885 WARN_ON_ONCE(queue_is_mq(q));
1886 q->nr_zones = blkdev_nr_zones(t->md->disk);
1890 blk_queue_update_readahead(q);
1893 unsigned int dm_table_get_num_targets(struct dm_table *t)
1895 return t->num_targets;
1898 struct list_head *dm_table_get_devices(struct dm_table *t)
1903 fmode_t dm_table_get_mode(struct dm_table *t)
1907 EXPORT_SYMBOL(dm_table_get_mode);
1915 static void suspend_targets(struct dm_table *t, enum suspend_mode mode)
1917 int i = t->num_targets;
1918 struct dm_target *ti = t->targets;
1920 lockdep_assert_held(&t->md->suspend_lock);
1925 if (ti->type->presuspend)
1926 ti->type->presuspend(ti);
1928 case PRESUSPEND_UNDO:
1929 if (ti->type->presuspend_undo)
1930 ti->type->presuspend_undo(ti);
1933 if (ti->type->postsuspend)
1934 ti->type->postsuspend(ti);
1941 void dm_table_presuspend_targets(struct dm_table *t)
1946 suspend_targets(t, PRESUSPEND);
1949 void dm_table_presuspend_undo_targets(struct dm_table *t)
1954 suspend_targets(t, PRESUSPEND_UNDO);
1957 void dm_table_postsuspend_targets(struct dm_table *t)
1962 suspend_targets(t, POSTSUSPEND);
1965 int dm_table_resume_targets(struct dm_table *t)
1969 lockdep_assert_held(&t->md->suspend_lock);
1971 for (i = 0; i < t->num_targets; i++) {
1972 struct dm_target *ti = t->targets + i;
1974 if (!ti->type->preresume)
1977 r = ti->type->preresume(ti);
1979 DMERR("%s: %s: preresume failed, error = %d",
1980 dm_device_name(t->md), ti->type->name, r);
1985 for (i = 0; i < t->num_targets; i++) {
1986 struct dm_target *ti = t->targets + i;
1988 if (ti->type->resume)
1989 ti->type->resume(ti);
1995 struct mapped_device *dm_table_get_md(struct dm_table *t)
1999 EXPORT_SYMBOL(dm_table_get_md);
2001 const char *dm_table_device_name(struct dm_table *t)
2003 return dm_device_name(t->md);
2005 EXPORT_SYMBOL_GPL(dm_table_device_name);
2007 void dm_table_run_md_queue_async(struct dm_table *t)
2009 if (!dm_table_request_based(t))
2013 blk_mq_run_hw_queues(t->md->queue, true);
2015 EXPORT_SYMBOL(dm_table_run_md_queue_async);