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/slab.h>
16 #include <linux/interrupt.h>
17 #include <linux/mutex.h>
18 #include <linux/delay.h>
19 #include <asm/atomic.h>
21 #define DM_MSG_PREFIX "table"
24 #define NODE_SIZE L1_CACHE_BYTES
25 #define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
26 #define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
29 * The table has always exactly one reference from either mapped_device->map
30 * or hash_cell->new_map. This reference is not counted in table->holders.
31 * A pair of dm_create_table/dm_destroy_table functions is used for table
32 * creation/destruction.
34 * Temporary references from the other code increase table->holders. A pair
35 * of dm_table_get/dm_table_put functions is used to manipulate it.
37 * When the table is about to be destroyed, we wait for table->holders to
42 struct mapped_device *md;
48 unsigned int counts[MAX_DEPTH]; /* in nodes */
49 sector_t *index[MAX_DEPTH];
51 unsigned int num_targets;
52 unsigned int num_allocated;
54 struct dm_target *targets;
57 * Indicates the rw permissions for the new logical
58 * device. This should be a combination of FMODE_READ
63 /* a list of devices used by this table */
64 struct list_head devices;
66 /* events get handed up using this callback */
67 void (*event_fn)(void *);
70 struct dm_md_mempools *mempools;
74 * Similar to ceiling(log_size(n))
76 static unsigned int int_log(unsigned int n, unsigned int base)
81 n = dm_div_up(n, base);
89 * Calculate the index of the child node of the n'th node k'th key.
91 static inline unsigned int get_child(unsigned int n, unsigned int k)
93 return (n * CHILDREN_PER_NODE) + k;
97 * Return the n'th node of level l from table t.
99 static inline sector_t *get_node(struct dm_table *t,
100 unsigned int l, unsigned int n)
102 return t->index[l] + (n * KEYS_PER_NODE);
106 * Return the highest key that you could lookup from the n'th
107 * node on level l of the btree.
109 static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
111 for (; l < t->depth - 1; l++)
112 n = get_child(n, CHILDREN_PER_NODE - 1);
114 if (n >= t->counts[l])
115 return (sector_t) - 1;
117 return get_node(t, l, n)[KEYS_PER_NODE - 1];
121 * Fills in a level of the btree based on the highs of the level
124 static int setup_btree_index(unsigned int l, struct dm_table *t)
129 for (n = 0U; n < t->counts[l]; n++) {
130 node = get_node(t, l, n);
132 for (k = 0U; k < KEYS_PER_NODE; k++)
133 node[k] = high(t, l + 1, get_child(n, k));
139 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
145 * Check that we're not going to overflow.
147 if (nmemb > (ULONG_MAX / elem_size))
150 size = nmemb * elem_size;
151 addr = vmalloc(size);
153 memset(addr, 0, size);
159 * highs, and targets are managed as dynamic arrays during a
162 static int alloc_targets(struct dm_table *t, unsigned int num)
165 struct dm_target *n_targets;
166 int n = t->num_targets;
169 * Allocate both the target array and offset array at once.
170 * Append an empty entry to catch sectors beyond the end of
173 n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
178 n_targets = (struct dm_target *) (n_highs + num);
181 memcpy(n_highs, t->highs, sizeof(*n_highs) * n);
182 memcpy(n_targets, t->targets, sizeof(*n_targets) * n);
185 memset(n_highs + n, -1, sizeof(*n_highs) * (num - n));
188 t->num_allocated = num;
190 t->targets = n_targets;
195 int dm_table_create(struct dm_table **result, fmode_t mode,
196 unsigned num_targets, struct mapped_device *md)
198 struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
203 INIT_LIST_HEAD(&t->devices);
204 atomic_set(&t->holders, 0);
207 num_targets = KEYS_PER_NODE;
209 num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
211 if (alloc_targets(t, num_targets)) {
223 static void free_devices(struct list_head *devices)
225 struct list_head *tmp, *next;
227 list_for_each_safe(tmp, next, devices) {
228 struct dm_dev_internal *dd =
229 list_entry(tmp, struct dm_dev_internal, list);
230 DMWARN("dm_table_destroy: dm_put_device call missing for %s",
236 void dm_table_destroy(struct dm_table *t)
240 while (atomic_read(&t->holders))
244 /* free the indexes (see dm_table_complete) */
246 vfree(t->index[t->depth - 2]);
248 /* free the targets */
249 for (i = 0; i < t->num_targets; i++) {
250 struct dm_target *tgt = t->targets + i;
255 dm_put_target_type(tgt->type);
260 /* free the device list */
261 if (t->devices.next != &t->devices)
262 free_devices(&t->devices);
264 dm_free_md_mempools(t->mempools);
269 void dm_table_get(struct dm_table *t)
271 atomic_inc(&t->holders);
274 void dm_table_put(struct dm_table *t)
279 smp_mb__before_atomic_dec();
280 atomic_dec(&t->holders);
284 * Checks to see if we need to extend highs or targets.
286 static inline int check_space(struct dm_table *t)
288 if (t->num_targets >= t->num_allocated)
289 return alloc_targets(t, t->num_allocated * 2);
295 * See if we've already got a device in the list.
297 static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
299 struct dm_dev_internal *dd;
301 list_for_each_entry (dd, l, list)
302 if (dd->dm_dev.bdev->bd_dev == dev)
309 * Open a device so we can use it as a map destination.
311 static int open_dev(struct dm_dev_internal *d, dev_t dev,
312 struct mapped_device *md)
314 static char *_claim_ptr = "I belong to device-mapper";
315 struct block_device *bdev;
319 BUG_ON(d->dm_dev.bdev);
321 bdev = open_by_devnum(dev, d->dm_dev.mode);
323 return PTR_ERR(bdev);
324 r = bd_claim_by_disk(bdev, _claim_ptr, dm_disk(md));
326 blkdev_put(bdev, d->dm_dev.mode);
328 d->dm_dev.bdev = bdev;
333 * Close a device that we've been using.
335 static void close_dev(struct dm_dev_internal *d, struct mapped_device *md)
340 bd_release_from_disk(d->dm_dev.bdev, dm_disk(md));
341 blkdev_put(d->dm_dev.bdev, d->dm_dev.mode);
342 d->dm_dev.bdev = NULL;
346 * If possible, this checks an area of a destination device is invalid.
348 static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
349 sector_t start, sector_t len, void *data)
351 struct queue_limits *limits = data;
352 struct block_device *bdev = dev->bdev;
354 i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
355 unsigned short logical_block_size_sectors =
356 limits->logical_block_size >> SECTOR_SHIFT;
357 char b[BDEVNAME_SIZE];
362 if ((start >= dev_size) || (start + len > dev_size)) {
363 DMWARN("%s: %s too small for target: "
364 "start=%llu, len=%llu, dev_size=%llu",
365 dm_device_name(ti->table->md), bdevname(bdev, b),
366 (unsigned long long)start,
367 (unsigned long long)len,
368 (unsigned long long)dev_size);
372 if (logical_block_size_sectors <= 1)
375 if (start & (logical_block_size_sectors - 1)) {
376 DMWARN("%s: start=%llu not aligned to h/w "
377 "logical block size %u of %s",
378 dm_device_name(ti->table->md),
379 (unsigned long long)start,
380 limits->logical_block_size, bdevname(bdev, b));
384 if (len & (logical_block_size_sectors - 1)) {
385 DMWARN("%s: len=%llu not aligned to h/w "
386 "logical block size %u of %s",
387 dm_device_name(ti->table->md),
388 (unsigned long long)len,
389 limits->logical_block_size, bdevname(bdev, b));
397 * This upgrades the mode on an already open dm_dev, being
398 * careful to leave things as they were if we fail to reopen the
399 * device and not to touch the existing bdev field in case
400 * it is accessed concurrently inside dm_table_any_congested().
402 static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
403 struct mapped_device *md)
406 struct dm_dev_internal dd_new, dd_old;
408 dd_new = dd_old = *dd;
410 dd_new.dm_dev.mode |= new_mode;
411 dd_new.dm_dev.bdev = NULL;
413 r = open_dev(&dd_new, dd->dm_dev.bdev->bd_dev, md);
417 dd->dm_dev.mode |= new_mode;
418 close_dev(&dd_old, md);
424 * Add a device to the list, or just increment the usage count if
425 * it's already present.
427 static int __table_get_device(struct dm_table *t, struct dm_target *ti,
428 const char *path, sector_t start, sector_t len,
429 fmode_t mode, struct dm_dev **result)
432 dev_t uninitialized_var(dev);
433 struct dm_dev_internal *dd;
434 unsigned int major, minor;
438 if (sscanf(path, "%u:%u", &major, &minor) == 2) {
439 /* Extract the major/minor numbers */
440 dev = MKDEV(major, minor);
441 if (MAJOR(dev) != major || MINOR(dev) != minor)
444 /* convert the path to a device */
445 struct block_device *bdev = lookup_bdev(path);
448 return PTR_ERR(bdev);
453 dd = find_device(&t->devices, dev);
455 dd = kmalloc(sizeof(*dd), GFP_KERNEL);
459 dd->dm_dev.mode = mode;
460 dd->dm_dev.bdev = NULL;
462 if ((r = open_dev(dd, dev, t->md))) {
467 format_dev_t(dd->dm_dev.name, dev);
469 atomic_set(&dd->count, 0);
470 list_add(&dd->list, &t->devices);
472 } else if (dd->dm_dev.mode != (mode | dd->dm_dev.mode)) {
473 r = upgrade_mode(dd, mode, t->md);
477 atomic_inc(&dd->count);
479 *result = &dd->dm_dev;
484 * Returns the minimum that is _not_ zero, unless both are zero.
486 #define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r))
488 int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
489 sector_t start, sector_t len, void *data)
491 struct queue_limits *limits = data;
492 struct block_device *bdev = dev->bdev;
493 struct request_queue *q = bdev_get_queue(bdev);
494 char b[BDEVNAME_SIZE];
497 DMWARN("%s: Cannot set limits for nonexistent device %s",
498 dm_device_name(ti->table->md), bdevname(bdev, b));
502 if (bdev_stack_limits(limits, bdev, start) < 0)
503 DMWARN("%s: adding target device %s caused an alignment inconsistency: "
504 "physical_block_size=%u, logical_block_size=%u, "
505 "alignment_offset=%u, start=%llu",
506 dm_device_name(ti->table->md), bdevname(bdev, b),
507 q->limits.physical_block_size,
508 q->limits.logical_block_size,
509 q->limits.alignment_offset,
510 (unsigned long long) start << SECTOR_SHIFT);
513 * Check if merge fn is supported.
514 * If not we'll force DM to use PAGE_SIZE or
515 * smaller I/O, just to be safe.
518 if (q->merge_bvec_fn && !ti->type->merge)
519 limits->max_sectors =
520 min_not_zero(limits->max_sectors,
521 (unsigned int) (PAGE_SIZE >> 9));
524 EXPORT_SYMBOL_GPL(dm_set_device_limits);
526 int dm_get_device(struct dm_target *ti, const char *path, sector_t start,
527 sector_t len, fmode_t mode, struct dm_dev **result)
529 return __table_get_device(ti->table, ti, path,
530 start, len, mode, result);
535 * Decrement a devices use count and remove it if necessary.
537 void dm_put_device(struct dm_target *ti, struct dm_dev *d)
539 struct dm_dev_internal *dd = container_of(d, struct dm_dev_internal,
542 if (atomic_dec_and_test(&dd->count)) {
543 close_dev(dd, ti->table->md);
550 * Checks to see if the target joins onto the end of the table.
552 static int adjoin(struct dm_table *table, struct dm_target *ti)
554 struct dm_target *prev;
556 if (!table->num_targets)
559 prev = &table->targets[table->num_targets - 1];
560 return (ti->begin == (prev->begin + prev->len));
564 * Used to dynamically allocate the arg array.
566 static char **realloc_argv(unsigned *array_size, char **old_argv)
571 new_size = *array_size ? *array_size * 2 : 64;
572 argv = kmalloc(new_size * sizeof(*argv), GFP_KERNEL);
574 memcpy(argv, old_argv, *array_size * sizeof(*argv));
575 *array_size = new_size;
583 * Destructively splits up the argument list to pass to ctr.
585 int dm_split_args(int *argc, char ***argvp, char *input)
587 char *start, *end = input, *out, **argv = NULL;
588 unsigned array_size = 0;
597 argv = realloc_argv(&array_size, argv);
604 /* Skip whitespace */
605 while (*start && isspace(*start))
609 break; /* success, we hit the end */
611 /* 'out' is used to remove any back-quotes */
614 /* Everything apart from '\0' can be quoted */
615 if (*end == '\\' && *(end + 1)) {
622 break; /* end of token */
627 /* have we already filled the array ? */
628 if ((*argc + 1) > array_size) {
629 argv = realloc_argv(&array_size, argv);
634 /* we know this is whitespace */
638 /* terminate the string and put it in the array */
649 * Impose necessary and sufficient conditions on a devices's table such
650 * that any incoming bio which respects its logical_block_size can be
651 * processed successfully. If it falls across the boundary between
652 * two or more targets, the size of each piece it gets split into must
653 * be compatible with the logical_block_size of the target processing it.
655 static int validate_hardware_logical_block_alignment(struct dm_table *table,
656 struct queue_limits *limits)
659 * This function uses arithmetic modulo the logical_block_size
660 * (in units of 512-byte sectors).
662 unsigned short device_logical_block_size_sects =
663 limits->logical_block_size >> SECTOR_SHIFT;
666 * Offset of the start of the next table entry, mod logical_block_size.
668 unsigned short next_target_start = 0;
671 * Given an aligned bio that extends beyond the end of a
672 * target, how many sectors must the next target handle?
674 unsigned short remaining = 0;
676 struct dm_target *uninitialized_var(ti);
677 struct queue_limits ti_limits;
681 * Check each entry in the table in turn.
683 while (i < dm_table_get_num_targets(table)) {
684 ti = dm_table_get_target(table, i++);
686 blk_set_default_limits(&ti_limits);
688 /* combine all target devices' limits */
689 if (ti->type->iterate_devices)
690 ti->type->iterate_devices(ti, dm_set_device_limits,
694 * If the remaining sectors fall entirely within this
695 * table entry are they compatible with its logical_block_size?
697 if (remaining < ti->len &&
698 remaining & ((ti_limits.logical_block_size >>
703 (unsigned short) ((next_target_start + ti->len) &
704 (device_logical_block_size_sects - 1));
705 remaining = next_target_start ?
706 device_logical_block_size_sects - next_target_start : 0;
710 DMWARN("%s: table line %u (start sect %llu len %llu) "
711 "not aligned to h/w logical block size %u",
712 dm_device_name(table->md), i,
713 (unsigned long long) ti->begin,
714 (unsigned long long) ti->len,
715 limits->logical_block_size);
722 int dm_table_add_target(struct dm_table *t, const char *type,
723 sector_t start, sector_t len, char *params)
725 int r = -EINVAL, argc;
727 struct dm_target *tgt;
729 if ((r = check_space(t)))
732 tgt = t->targets + t->num_targets;
733 memset(tgt, 0, sizeof(*tgt));
736 DMERR("%s: zero-length target", dm_device_name(t->md));
740 tgt->type = dm_get_target_type(type);
742 DMERR("%s: %s: unknown target type", dm_device_name(t->md),
750 tgt->error = "Unknown error";
753 * Does this target adjoin the previous one ?
755 if (!adjoin(t, tgt)) {
756 tgt->error = "Gap in table";
761 r = dm_split_args(&argc, &argv, params);
763 tgt->error = "couldn't split parameters (insufficient memory)";
767 r = tgt->type->ctr(tgt, argc, argv);
772 t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
777 DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
778 dm_put_target_type(tgt->type);
782 int dm_table_set_type(struct dm_table *t)
785 unsigned bio_based = 0, request_based = 0;
786 struct dm_target *tgt;
787 struct dm_dev_internal *dd;
788 struct list_head *devices;
790 for (i = 0; i < t->num_targets; i++) {
791 tgt = t->targets + i;
792 if (dm_target_request_based(tgt))
797 if (bio_based && request_based) {
798 DMWARN("Inconsistent table: different target types"
799 " can't be mixed up");
805 /* We must use this table as bio-based */
806 t->type = DM_TYPE_BIO_BASED;
810 BUG_ON(!request_based); /* No targets in this table */
812 /* Non-request-stackable devices can't be used for request-based dm */
813 devices = dm_table_get_devices(t);
814 list_for_each_entry(dd, devices, list) {
815 if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev.bdev))) {
816 DMWARN("table load rejected: including"
817 " non-request-stackable devices");
823 * Request-based dm supports only tables that have a single target now.
824 * To support multiple targets, request splitting support is needed,
825 * and that needs lots of changes in the block-layer.
826 * (e.g. request completion process for partial completion.)
828 if (t->num_targets > 1) {
829 DMWARN("Request-based dm doesn't support multiple targets yet");
833 t->type = DM_TYPE_REQUEST_BASED;
838 unsigned dm_table_get_type(struct dm_table *t)
843 bool dm_table_request_based(struct dm_table *t)
845 return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED;
848 int dm_table_alloc_md_mempools(struct dm_table *t)
850 unsigned type = dm_table_get_type(t);
852 if (unlikely(type == DM_TYPE_NONE)) {
853 DMWARN("no table type is set, can't allocate mempools");
857 t->mempools = dm_alloc_md_mempools(type);
864 void dm_table_free_md_mempools(struct dm_table *t)
866 dm_free_md_mempools(t->mempools);
870 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
875 static int setup_indexes(struct dm_table *t)
878 unsigned int total = 0;
881 /* allocate the space for *all* the indexes */
882 for (i = t->depth - 2; i >= 0; i--) {
883 t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
884 total += t->counts[i];
887 indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE);
891 /* set up internal nodes, bottom-up */
892 for (i = t->depth - 2; i >= 0; i--) {
893 t->index[i] = indexes;
894 indexes += (KEYS_PER_NODE * t->counts[i]);
895 setup_btree_index(i, t);
902 * Builds the btree to index the map.
904 int dm_table_complete(struct dm_table *t)
907 unsigned int leaf_nodes;
909 /* how many indexes will the btree have ? */
910 leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
911 t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
913 /* leaf layer has already been set up */
914 t->counts[t->depth - 1] = leaf_nodes;
915 t->index[t->depth - 1] = t->highs;
918 r = setup_indexes(t);
923 static DEFINE_MUTEX(_event_lock);
924 void dm_table_event_callback(struct dm_table *t,
925 void (*fn)(void *), void *context)
927 mutex_lock(&_event_lock);
929 t->event_context = context;
930 mutex_unlock(&_event_lock);
933 void dm_table_event(struct dm_table *t)
936 * You can no longer call dm_table_event() from interrupt
937 * context, use a bottom half instead.
939 BUG_ON(in_interrupt());
941 mutex_lock(&_event_lock);
943 t->event_fn(t->event_context);
944 mutex_unlock(&_event_lock);
947 sector_t dm_table_get_size(struct dm_table *t)
949 return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
952 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
954 if (index >= t->num_targets)
957 return t->targets + index;
961 * Search the btree for the correct target.
963 * Caller should check returned pointer with dm_target_is_valid()
964 * to trap I/O beyond end of device.
966 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
968 unsigned int l, n = 0, k = 0;
971 for (l = 0; l < t->depth; l++) {
973 node = get_node(t, l, n);
975 for (k = 0; k < KEYS_PER_NODE; k++)
976 if (node[k] >= sector)
980 return &t->targets[(KEYS_PER_NODE * n) + k];
984 * Establish the new table's queue_limits and validate them.
986 int dm_calculate_queue_limits(struct dm_table *table,
987 struct queue_limits *limits)
989 struct dm_target *uninitialized_var(ti);
990 struct queue_limits ti_limits;
993 blk_set_default_limits(limits);
995 while (i < dm_table_get_num_targets(table)) {
996 blk_set_default_limits(&ti_limits);
998 ti = dm_table_get_target(table, i++);
1000 if (!ti->type->iterate_devices)
1001 goto combine_limits;
1004 * Combine queue limits of all the devices this target uses.
1006 ti->type->iterate_devices(ti, dm_set_device_limits,
1009 /* Set I/O hints portion of queue limits */
1010 if (ti->type->io_hints)
1011 ti->type->io_hints(ti, &ti_limits);
1014 * Check each device area is consistent with the target's
1015 * overall queue limits.
1017 if (ti->type->iterate_devices(ti, device_area_is_invalid,
1023 * Merge this target's queue limits into the overall limits
1026 if (blk_stack_limits(limits, &ti_limits, 0) < 0)
1027 DMWARN("%s: adding target device "
1028 "(start sect %llu len %llu) "
1029 "caused an alignment inconsistency",
1030 dm_device_name(table->md),
1031 (unsigned long long) ti->begin,
1032 (unsigned long long) ti->len);
1035 return validate_hardware_logical_block_alignment(table, limits);
1039 * Set the integrity profile for this device if all devices used have
1040 * matching profiles.
1042 static void dm_table_set_integrity(struct dm_table *t)
1044 struct list_head *devices = dm_table_get_devices(t);
1045 struct dm_dev_internal *prev = NULL, *dd = NULL;
1047 if (!blk_get_integrity(dm_disk(t->md)))
1050 list_for_each_entry(dd, devices, list) {
1052 blk_integrity_compare(prev->dm_dev.bdev->bd_disk,
1053 dd->dm_dev.bdev->bd_disk) < 0) {
1054 DMWARN("%s: integrity not set: %s and %s mismatch",
1055 dm_device_name(t->md),
1056 prev->dm_dev.bdev->bd_disk->disk_name,
1057 dd->dm_dev.bdev->bd_disk->disk_name);
1063 if (!prev || !bdev_get_integrity(prev->dm_dev.bdev))
1066 blk_integrity_register(dm_disk(t->md),
1067 bdev_get_integrity(prev->dm_dev.bdev));
1072 blk_integrity_register(dm_disk(t->md), NULL);
1077 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1078 struct queue_limits *limits)
1081 * Copy table's limits to the DM device's request_queue
1083 q->limits = *limits;
1085 if (limits->no_cluster)
1086 queue_flag_clear_unlocked(QUEUE_FLAG_CLUSTER, q);
1088 queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, q);
1090 dm_table_set_integrity(t);
1093 * QUEUE_FLAG_STACKABLE must be set after all queue settings are
1094 * visible to other CPUs because, once the flag is set, incoming bios
1095 * are processed by request-based dm, which refers to the queue
1097 * Until the flag set, bios are passed to bio-based dm and queued to
1098 * md->deferred where queue settings are not needed yet.
1099 * Those bios are passed to request-based dm at the resume time.
1102 if (dm_table_request_based(t))
1103 queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q);
1106 unsigned int dm_table_get_num_targets(struct dm_table *t)
1108 return t->num_targets;
1111 struct list_head *dm_table_get_devices(struct dm_table *t)
1116 fmode_t dm_table_get_mode(struct dm_table *t)
1121 static void suspend_targets(struct dm_table *t, unsigned postsuspend)
1123 int i = t->num_targets;
1124 struct dm_target *ti = t->targets;
1128 if (ti->type->postsuspend)
1129 ti->type->postsuspend(ti);
1130 } else if (ti->type->presuspend)
1131 ti->type->presuspend(ti);
1137 void dm_table_presuspend_targets(struct dm_table *t)
1142 suspend_targets(t, 0);
1145 void dm_table_postsuspend_targets(struct dm_table *t)
1150 suspend_targets(t, 1);
1153 int dm_table_resume_targets(struct dm_table *t)
1157 for (i = 0; i < t->num_targets; i++) {
1158 struct dm_target *ti = t->targets + i;
1160 if (!ti->type->preresume)
1163 r = ti->type->preresume(ti);
1168 for (i = 0; i < t->num_targets; i++) {
1169 struct dm_target *ti = t->targets + i;
1171 if (ti->type->resume)
1172 ti->type->resume(ti);
1178 int dm_table_any_congested(struct dm_table *t, int bdi_bits)
1180 struct dm_dev_internal *dd;
1181 struct list_head *devices = dm_table_get_devices(t);
1184 list_for_each_entry(dd, devices, list) {
1185 struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev);
1186 char b[BDEVNAME_SIZE];
1189 r |= bdi_congested(&q->backing_dev_info, bdi_bits);
1191 DMWARN_LIMIT("%s: any_congested: nonexistent device %s",
1192 dm_device_name(t->md),
1193 bdevname(dd->dm_dev.bdev, b));
1199 int dm_table_any_busy_target(struct dm_table *t)
1202 struct dm_target *ti;
1204 for (i = 0; i < t->num_targets; i++) {
1205 ti = t->targets + i;
1206 if (ti->type->busy && ti->type->busy(ti))
1213 void dm_table_unplug_all(struct dm_table *t)
1215 struct dm_dev_internal *dd;
1216 struct list_head *devices = dm_table_get_devices(t);
1218 list_for_each_entry(dd, devices, list) {
1219 struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev);
1220 char b[BDEVNAME_SIZE];
1225 DMWARN_LIMIT("%s: Cannot unplug nonexistent device %s",
1226 dm_device_name(t->md),
1227 bdevname(dd->dm_dev.bdev, b));
1231 struct mapped_device *dm_table_get_md(struct dm_table *t)
1238 EXPORT_SYMBOL(dm_vcalloc);
1239 EXPORT_SYMBOL(dm_get_device);
1240 EXPORT_SYMBOL(dm_put_device);
1241 EXPORT_SYMBOL(dm_table_event);
1242 EXPORT_SYMBOL(dm_table_get_size);
1243 EXPORT_SYMBOL(dm_table_get_mode);
1244 EXPORT_SYMBOL(dm_table_get_md);
1245 EXPORT_SYMBOL(dm_table_put);
1246 EXPORT_SYMBOL(dm_table_get);
1247 EXPORT_SYMBOL(dm_table_unplug_all);