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 <asm/atomic.h>
22 #define DM_MSG_PREFIX "table"
25 #define NODE_SIZE L1_CACHE_BYTES
26 #define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
27 #define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
30 * The table has always exactly one reference from either mapped_device->map
31 * or hash_cell->new_map. This reference is not counted in table->holders.
32 * A pair of dm_create_table/dm_destroy_table functions is used for table
33 * creation/destruction.
35 * Temporary references from the other code increase table->holders. A pair
36 * of dm_table_get/dm_table_put functions is used to manipulate it.
38 * When the table is about to be destroyed, we wait for table->holders to
43 struct mapped_device *md;
49 unsigned int counts[MAX_DEPTH]; /* in nodes */
50 sector_t *index[MAX_DEPTH];
52 unsigned int num_targets;
53 unsigned int num_allocated;
55 struct dm_target *targets;
58 * Indicates the rw permissions for the new logical
59 * device. This should be a combination of FMODE_READ
64 /* a list of devices used by this table */
65 struct list_head devices;
67 /* events get handed up using this callback */
68 void (*event_fn)(void *);
71 struct dm_md_mempools *mempools;
75 * Similar to ceiling(log_size(n))
77 static unsigned int int_log(unsigned int n, unsigned int base)
82 n = dm_div_up(n, base);
90 * Calculate the index of the child node of the n'th node k'th key.
92 static inline unsigned int get_child(unsigned int n, unsigned int k)
94 return (n * CHILDREN_PER_NODE) + k;
98 * Return the n'th node of level l from table t.
100 static inline sector_t *get_node(struct dm_table *t,
101 unsigned int l, unsigned int n)
103 return t->index[l] + (n * KEYS_PER_NODE);
107 * Return the highest key that you could lookup from the n'th
108 * node on level l of the btree.
110 static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
112 for (; l < t->depth - 1; l++)
113 n = get_child(n, CHILDREN_PER_NODE - 1);
115 if (n >= t->counts[l])
116 return (sector_t) - 1;
118 return get_node(t, l, n)[KEYS_PER_NODE - 1];
122 * Fills in a level of the btree based on the highs of the level
125 static int setup_btree_index(unsigned int l, struct dm_table *t)
130 for (n = 0U; n < t->counts[l]; n++) {
131 node = get_node(t, l, n);
133 for (k = 0U; k < KEYS_PER_NODE; k++)
134 node[k] = high(t, l + 1, get_child(n, k));
140 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
146 * Check that we're not going to overflow.
148 if (nmemb > (ULONG_MAX / elem_size))
151 size = nmemb * elem_size;
152 addr = vmalloc(size);
154 memset(addr, 0, size);
160 * highs, and targets are managed as dynamic arrays during a
163 static int alloc_targets(struct dm_table *t, unsigned int num)
166 struct dm_target *n_targets;
167 int n = t->num_targets;
170 * Allocate both the target array and offset array at once.
171 * Append an empty entry to catch sectors beyond the end of
174 n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
179 n_targets = (struct dm_target *) (n_highs + num);
182 memcpy(n_highs, t->highs, sizeof(*n_highs) * n);
183 memcpy(n_targets, t->targets, sizeof(*n_targets) * n);
186 memset(n_highs + n, -1, sizeof(*n_highs) * (num - n));
189 t->num_allocated = num;
191 t->targets = n_targets;
196 int dm_table_create(struct dm_table **result, fmode_t mode,
197 unsigned num_targets, struct mapped_device *md)
199 struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
204 INIT_LIST_HEAD(&t->devices);
205 atomic_set(&t->holders, 0);
208 num_targets = KEYS_PER_NODE;
210 num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
212 if (alloc_targets(t, num_targets)) {
224 static void free_devices(struct list_head *devices)
226 struct list_head *tmp, *next;
228 list_for_each_safe(tmp, next, devices) {
229 struct dm_dev_internal *dd =
230 list_entry(tmp, struct dm_dev_internal, list);
231 DMWARN("dm_table_destroy: dm_put_device call missing for %s",
237 void dm_table_destroy(struct dm_table *t)
244 while (atomic_read(&t->holders))
248 /* free the indexes (see dm_table_complete) */
250 vfree(t->index[t->depth - 2]);
252 /* free the targets */
253 for (i = 0; i < t->num_targets; i++) {
254 struct dm_target *tgt = t->targets + i;
259 dm_put_target_type(tgt->type);
264 /* free the device list */
265 if (t->devices.next != &t->devices)
266 free_devices(&t->devices);
268 dm_free_md_mempools(t->mempools);
273 void dm_table_get(struct dm_table *t)
275 atomic_inc(&t->holders);
278 void dm_table_put(struct dm_table *t)
283 smp_mb__before_atomic_dec();
284 atomic_dec(&t->holders);
288 * Checks to see if we need to extend highs or targets.
290 static inline int check_space(struct dm_table *t)
292 if (t->num_targets >= t->num_allocated)
293 return alloc_targets(t, t->num_allocated * 2);
299 * See if we've already got a device in the list.
301 static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
303 struct dm_dev_internal *dd;
305 list_for_each_entry (dd, l, list)
306 if (dd->dm_dev.bdev->bd_dev == dev)
313 * Open a device so we can use it as a map destination.
315 static int open_dev(struct dm_dev_internal *d, dev_t dev,
316 struct mapped_device *md)
318 static char *_claim_ptr = "I belong to device-mapper";
319 struct block_device *bdev;
323 BUG_ON(d->dm_dev.bdev);
325 bdev = open_by_devnum(dev, d->dm_dev.mode);
327 return PTR_ERR(bdev);
328 r = bd_claim_by_disk(bdev, _claim_ptr, dm_disk(md));
330 blkdev_put(bdev, d->dm_dev.mode);
332 d->dm_dev.bdev = bdev;
337 * Close a device that we've been using.
339 static void close_dev(struct dm_dev_internal *d, struct mapped_device *md)
344 bd_release_from_disk(d->dm_dev.bdev, dm_disk(md));
345 blkdev_put(d->dm_dev.bdev, d->dm_dev.mode);
346 d->dm_dev.bdev = NULL;
350 * If possible, this checks an area of a destination device is invalid.
352 static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
353 sector_t start, sector_t len, void *data)
355 struct queue_limits *limits = data;
356 struct block_device *bdev = dev->bdev;
358 i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
359 unsigned short logical_block_size_sectors =
360 limits->logical_block_size >> SECTOR_SHIFT;
361 char b[BDEVNAME_SIZE];
366 if ((start >= dev_size) || (start + len > dev_size)) {
367 DMWARN("%s: %s too small for target: "
368 "start=%llu, len=%llu, dev_size=%llu",
369 dm_device_name(ti->table->md), bdevname(bdev, b),
370 (unsigned long long)start,
371 (unsigned long long)len,
372 (unsigned long long)dev_size);
376 if (logical_block_size_sectors <= 1)
379 if (start & (logical_block_size_sectors - 1)) {
380 DMWARN("%s: start=%llu not aligned to h/w "
381 "logical block size %u of %s",
382 dm_device_name(ti->table->md),
383 (unsigned long long)start,
384 limits->logical_block_size, bdevname(bdev, b));
388 if (len & (logical_block_size_sectors - 1)) {
389 DMWARN("%s: len=%llu not aligned to h/w "
390 "logical block size %u of %s",
391 dm_device_name(ti->table->md),
392 (unsigned long long)len,
393 limits->logical_block_size, bdevname(bdev, b));
401 * This upgrades the mode on an already open dm_dev, being
402 * careful to leave things as they were if we fail to reopen the
403 * device and not to touch the existing bdev field in case
404 * it is accessed concurrently inside dm_table_any_congested().
406 static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
407 struct mapped_device *md)
410 struct dm_dev_internal dd_new, dd_old;
412 dd_new = dd_old = *dd;
414 dd_new.dm_dev.mode |= new_mode;
415 dd_new.dm_dev.bdev = NULL;
417 r = open_dev(&dd_new, dd->dm_dev.bdev->bd_dev, md);
421 dd->dm_dev.mode |= new_mode;
422 close_dev(&dd_old, md);
428 * Add a device to the list, or just increment the usage count if
429 * it's already present.
431 static int __table_get_device(struct dm_table *t, struct dm_target *ti,
432 const char *path, sector_t start, sector_t len,
433 fmode_t mode, struct dm_dev **result)
436 dev_t uninitialized_var(dev);
437 struct dm_dev_internal *dd;
438 unsigned int major, minor;
442 if (sscanf(path, "%u:%u", &major, &minor) == 2) {
443 /* Extract the major/minor numbers */
444 dev = MKDEV(major, minor);
445 if (MAJOR(dev) != major || MINOR(dev) != minor)
448 /* convert the path to a device */
449 struct block_device *bdev = lookup_bdev(path);
452 return PTR_ERR(bdev);
457 dd = find_device(&t->devices, dev);
459 dd = kmalloc(sizeof(*dd), GFP_KERNEL);
463 dd->dm_dev.mode = mode;
464 dd->dm_dev.bdev = NULL;
466 if ((r = open_dev(dd, dev, t->md))) {
471 format_dev_t(dd->dm_dev.name, dev);
473 atomic_set(&dd->count, 0);
474 list_add(&dd->list, &t->devices);
476 } else if (dd->dm_dev.mode != (mode | dd->dm_dev.mode)) {
477 r = upgrade_mode(dd, mode, t->md);
481 atomic_inc(&dd->count);
483 *result = &dd->dm_dev;
488 * Returns the minimum that is _not_ zero, unless both are zero.
490 #define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r))
492 int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
493 sector_t start, sector_t len, void *data)
495 struct queue_limits *limits = data;
496 struct block_device *bdev = dev->bdev;
497 struct request_queue *q = bdev_get_queue(bdev);
498 char b[BDEVNAME_SIZE];
501 DMWARN("%s: Cannot set limits for nonexistent device %s",
502 dm_device_name(ti->table->md), bdevname(bdev, b));
506 if (bdev_stack_limits(limits, bdev, start) < 0)
507 DMWARN("%s: adding target device %s caused an alignment inconsistency: "
508 "physical_block_size=%u, logical_block_size=%u, "
509 "alignment_offset=%u, start=%llu",
510 dm_device_name(ti->table->md), bdevname(bdev, b),
511 q->limits.physical_block_size,
512 q->limits.logical_block_size,
513 q->limits.alignment_offset,
514 (unsigned long long) start << SECTOR_SHIFT);
517 * Check if merge fn is supported.
518 * If not we'll force DM to use PAGE_SIZE or
519 * smaller I/O, just to be safe.
522 if (q->merge_bvec_fn && !ti->type->merge)
523 limits->max_sectors =
524 min_not_zero(limits->max_sectors,
525 (unsigned int) (PAGE_SIZE >> 9));
528 EXPORT_SYMBOL_GPL(dm_set_device_limits);
530 int dm_get_device(struct dm_target *ti, const char *path, sector_t start,
531 sector_t len, fmode_t mode, struct dm_dev **result)
533 return __table_get_device(ti->table, ti, path,
534 start, len, mode, result);
539 * Decrement a devices use count and remove it if necessary.
541 void dm_put_device(struct dm_target *ti, struct dm_dev *d)
543 struct dm_dev_internal *dd = container_of(d, struct dm_dev_internal,
546 if (atomic_dec_and_test(&dd->count)) {
547 close_dev(dd, ti->table->md);
554 * Checks to see if the target joins onto the end of the table.
556 static int adjoin(struct dm_table *table, struct dm_target *ti)
558 struct dm_target *prev;
560 if (!table->num_targets)
563 prev = &table->targets[table->num_targets - 1];
564 return (ti->begin == (prev->begin + prev->len));
568 * Used to dynamically allocate the arg array.
570 static char **realloc_argv(unsigned *array_size, char **old_argv)
575 new_size = *array_size ? *array_size * 2 : 64;
576 argv = kmalloc(new_size * sizeof(*argv), GFP_KERNEL);
578 memcpy(argv, old_argv, *array_size * sizeof(*argv));
579 *array_size = new_size;
587 * Destructively splits up the argument list to pass to ctr.
589 int dm_split_args(int *argc, char ***argvp, char *input)
591 char *start, *end = input, *out, **argv = NULL;
592 unsigned array_size = 0;
601 argv = realloc_argv(&array_size, argv);
606 /* Skip whitespace */
607 start = skip_spaces(end);
610 break; /* success, we hit the end */
612 /* 'out' is used to remove any back-quotes */
615 /* Everything apart from '\0' can be quoted */
616 if (*end == '\\' && *(end + 1)) {
623 break; /* end of token */
628 /* have we already filled the array ? */
629 if ((*argc + 1) > array_size) {
630 argv = realloc_argv(&array_size, argv);
635 /* we know this is whitespace */
639 /* terminate the string and put it in the array */
650 * Impose necessary and sufficient conditions on a devices's table such
651 * that any incoming bio which respects its logical_block_size can be
652 * processed successfully. If it falls across the boundary between
653 * two or more targets, the size of each piece it gets split into must
654 * be compatible with the logical_block_size of the target processing it.
656 static int validate_hardware_logical_block_alignment(struct dm_table *table,
657 struct queue_limits *limits)
660 * This function uses arithmetic modulo the logical_block_size
661 * (in units of 512-byte sectors).
663 unsigned short device_logical_block_size_sects =
664 limits->logical_block_size >> SECTOR_SHIFT;
667 * Offset of the start of the next table entry, mod logical_block_size.
669 unsigned short next_target_start = 0;
672 * Given an aligned bio that extends beyond the end of a
673 * target, how many sectors must the next target handle?
675 unsigned short remaining = 0;
677 struct dm_target *uninitialized_var(ti);
678 struct queue_limits ti_limits;
682 * Check each entry in the table in turn.
684 while (i < dm_table_get_num_targets(table)) {
685 ti = dm_table_get_target(table, i++);
687 blk_set_default_limits(&ti_limits);
689 /* combine all target devices' limits */
690 if (ti->type->iterate_devices)
691 ti->type->iterate_devices(ti, dm_set_device_limits,
695 * If the remaining sectors fall entirely within this
696 * table entry are they compatible with its logical_block_size?
698 if (remaining < ti->len &&
699 remaining & ((ti_limits.logical_block_size >>
704 (unsigned short) ((next_target_start + ti->len) &
705 (device_logical_block_size_sects - 1));
706 remaining = next_target_start ?
707 device_logical_block_size_sects - next_target_start : 0;
711 DMWARN("%s: table line %u (start sect %llu len %llu) "
712 "not aligned to h/w logical block size %u",
713 dm_device_name(table->md), i,
714 (unsigned long long) ti->begin,
715 (unsigned long long) ti->len,
716 limits->logical_block_size);
723 int dm_table_add_target(struct dm_table *t, const char *type,
724 sector_t start, sector_t len, char *params)
726 int r = -EINVAL, argc;
728 struct dm_target *tgt;
730 if ((r = check_space(t)))
733 tgt = t->targets + t->num_targets;
734 memset(tgt, 0, sizeof(*tgt));
737 DMERR("%s: zero-length target", dm_device_name(t->md));
741 tgt->type = dm_get_target_type(type);
743 DMERR("%s: %s: unknown target type", dm_device_name(t->md),
751 tgt->error = "Unknown error";
754 * Does this target adjoin the previous one ?
756 if (!adjoin(t, tgt)) {
757 tgt->error = "Gap in table";
762 r = dm_split_args(&argc, &argv, params);
764 tgt->error = "couldn't split parameters (insufficient memory)";
768 r = tgt->type->ctr(tgt, argc, argv);
773 t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
778 DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
779 dm_put_target_type(tgt->type);
783 int dm_table_set_type(struct dm_table *t)
786 unsigned bio_based = 0, request_based = 0;
787 struct dm_target *tgt;
788 struct dm_dev_internal *dd;
789 struct list_head *devices;
791 for (i = 0; i < t->num_targets; i++) {
792 tgt = t->targets + i;
793 if (dm_target_request_based(tgt))
798 if (bio_based && request_based) {
799 DMWARN("Inconsistent table: different target types"
800 " can't be mixed up");
806 /* We must use this table as bio-based */
807 t->type = DM_TYPE_BIO_BASED;
811 BUG_ON(!request_based); /* No targets in this table */
813 /* Non-request-stackable devices can't be used for request-based dm */
814 devices = dm_table_get_devices(t);
815 list_for_each_entry(dd, devices, list) {
816 if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev.bdev))) {
817 DMWARN("table load rejected: including"
818 " non-request-stackable devices");
824 * Request-based dm supports only tables that have a single target now.
825 * To support multiple targets, request splitting support is needed,
826 * and that needs lots of changes in the block-layer.
827 * (e.g. request completion process for partial completion.)
829 if (t->num_targets > 1) {
830 DMWARN("Request-based dm doesn't support multiple targets yet");
834 t->type = DM_TYPE_REQUEST_BASED;
839 unsigned dm_table_get_type(struct dm_table *t)
844 bool dm_table_request_based(struct dm_table *t)
846 return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED;
849 int dm_table_alloc_md_mempools(struct dm_table *t)
851 unsigned type = dm_table_get_type(t);
853 if (unlikely(type == DM_TYPE_NONE)) {
854 DMWARN("no table type is set, can't allocate mempools");
858 t->mempools = dm_alloc_md_mempools(type);
865 void dm_table_free_md_mempools(struct dm_table *t)
867 dm_free_md_mempools(t->mempools);
871 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
876 static int setup_indexes(struct dm_table *t)
879 unsigned int total = 0;
882 /* allocate the space for *all* the indexes */
883 for (i = t->depth - 2; i >= 0; i--) {
884 t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
885 total += t->counts[i];
888 indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE);
892 /* set up internal nodes, bottom-up */
893 for (i = t->depth - 2; i >= 0; i--) {
894 t->index[i] = indexes;
895 indexes += (KEYS_PER_NODE * t->counts[i]);
896 setup_btree_index(i, t);
903 * Builds the btree to index the map.
905 int dm_table_complete(struct dm_table *t)
908 unsigned int leaf_nodes;
910 /* how many indexes will the btree have ? */
911 leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
912 t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
914 /* leaf layer has already been set up */
915 t->counts[t->depth - 1] = leaf_nodes;
916 t->index[t->depth - 1] = t->highs;
919 r = setup_indexes(t);
924 static DEFINE_MUTEX(_event_lock);
925 void dm_table_event_callback(struct dm_table *t,
926 void (*fn)(void *), void *context)
928 mutex_lock(&_event_lock);
930 t->event_context = context;
931 mutex_unlock(&_event_lock);
934 void dm_table_event(struct dm_table *t)
937 * You can no longer call dm_table_event() from interrupt
938 * context, use a bottom half instead.
940 BUG_ON(in_interrupt());
942 mutex_lock(&_event_lock);
944 t->event_fn(t->event_context);
945 mutex_unlock(&_event_lock);
948 sector_t dm_table_get_size(struct dm_table *t)
950 return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
953 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
955 if (index >= t->num_targets)
958 return t->targets + index;
962 * Search the btree for the correct target.
964 * Caller should check returned pointer with dm_target_is_valid()
965 * to trap I/O beyond end of device.
967 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
969 unsigned int l, n = 0, k = 0;
972 for (l = 0; l < t->depth; l++) {
974 node = get_node(t, l, n);
976 for (k = 0; k < KEYS_PER_NODE; k++)
977 if (node[k] >= sector)
981 return &t->targets[(KEYS_PER_NODE * n) + k];
985 * Establish the new table's queue_limits and validate them.
987 int dm_calculate_queue_limits(struct dm_table *table,
988 struct queue_limits *limits)
990 struct dm_target *uninitialized_var(ti);
991 struct queue_limits ti_limits;
994 blk_set_default_limits(limits);
996 while (i < dm_table_get_num_targets(table)) {
997 blk_set_default_limits(&ti_limits);
999 ti = dm_table_get_target(table, i++);
1001 if (!ti->type->iterate_devices)
1002 goto combine_limits;
1005 * Combine queue limits of all the devices this target uses.
1007 ti->type->iterate_devices(ti, dm_set_device_limits,
1010 /* Set I/O hints portion of queue limits */
1011 if (ti->type->io_hints)
1012 ti->type->io_hints(ti, &ti_limits);
1015 * Check each device area is consistent with the target's
1016 * overall queue limits.
1018 if (ti->type->iterate_devices(ti, device_area_is_invalid,
1024 * Merge this target's queue limits into the overall limits
1027 if (blk_stack_limits(limits, &ti_limits, 0) < 0)
1028 DMWARN("%s: adding target device "
1029 "(start sect %llu len %llu) "
1030 "caused an alignment inconsistency",
1031 dm_device_name(table->md),
1032 (unsigned long long) ti->begin,
1033 (unsigned long long) ti->len);
1036 return validate_hardware_logical_block_alignment(table, limits);
1040 * Set the integrity profile for this device if all devices used have
1041 * matching profiles.
1043 static void dm_table_set_integrity(struct dm_table *t)
1045 struct list_head *devices = dm_table_get_devices(t);
1046 struct dm_dev_internal *prev = NULL, *dd = NULL;
1048 if (!blk_get_integrity(dm_disk(t->md)))
1051 list_for_each_entry(dd, devices, list) {
1053 blk_integrity_compare(prev->dm_dev.bdev->bd_disk,
1054 dd->dm_dev.bdev->bd_disk) < 0) {
1055 DMWARN("%s: integrity not set: %s and %s mismatch",
1056 dm_device_name(t->md),
1057 prev->dm_dev.bdev->bd_disk->disk_name,
1058 dd->dm_dev.bdev->bd_disk->disk_name);
1064 if (!prev || !bdev_get_integrity(prev->dm_dev.bdev))
1067 blk_integrity_register(dm_disk(t->md),
1068 bdev_get_integrity(prev->dm_dev.bdev));
1073 blk_integrity_register(dm_disk(t->md), NULL);
1078 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1079 struct queue_limits *limits)
1082 * Copy table's limits to the DM device's request_queue
1084 q->limits = *limits;
1086 if (limits->no_cluster)
1087 queue_flag_clear_unlocked(QUEUE_FLAG_CLUSTER, q);
1089 queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, q);
1091 dm_table_set_integrity(t);
1094 * QUEUE_FLAG_STACKABLE must be set after all queue settings are
1095 * visible to other CPUs because, once the flag is set, incoming bios
1096 * are processed by request-based dm, which refers to the queue
1098 * Until the flag set, bios are passed to bio-based dm and queued to
1099 * md->deferred where queue settings are not needed yet.
1100 * Those bios are passed to request-based dm at the resume time.
1103 if (dm_table_request_based(t))
1104 queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q);
1107 unsigned int dm_table_get_num_targets(struct dm_table *t)
1109 return t->num_targets;
1112 struct list_head *dm_table_get_devices(struct dm_table *t)
1117 fmode_t dm_table_get_mode(struct dm_table *t)
1122 static void suspend_targets(struct dm_table *t, unsigned postsuspend)
1124 int i = t->num_targets;
1125 struct dm_target *ti = t->targets;
1129 if (ti->type->postsuspend)
1130 ti->type->postsuspend(ti);
1131 } else if (ti->type->presuspend)
1132 ti->type->presuspend(ti);
1138 void dm_table_presuspend_targets(struct dm_table *t)
1143 suspend_targets(t, 0);
1146 void dm_table_postsuspend_targets(struct dm_table *t)
1151 suspend_targets(t, 1);
1154 int dm_table_resume_targets(struct dm_table *t)
1158 for (i = 0; i < t->num_targets; i++) {
1159 struct dm_target *ti = t->targets + i;
1161 if (!ti->type->preresume)
1164 r = ti->type->preresume(ti);
1169 for (i = 0; i < t->num_targets; i++) {
1170 struct dm_target *ti = t->targets + i;
1172 if (ti->type->resume)
1173 ti->type->resume(ti);
1179 int dm_table_any_congested(struct dm_table *t, int bdi_bits)
1181 struct dm_dev_internal *dd;
1182 struct list_head *devices = dm_table_get_devices(t);
1185 list_for_each_entry(dd, devices, list) {
1186 struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev);
1187 char b[BDEVNAME_SIZE];
1190 r |= bdi_congested(&q->backing_dev_info, bdi_bits);
1192 DMWARN_LIMIT("%s: any_congested: nonexistent device %s",
1193 dm_device_name(t->md),
1194 bdevname(dd->dm_dev.bdev, b));
1200 int dm_table_any_busy_target(struct dm_table *t)
1203 struct dm_target *ti;
1205 for (i = 0; i < t->num_targets; i++) {
1206 ti = t->targets + i;
1207 if (ti->type->busy && ti->type->busy(ti))
1214 void dm_table_unplug_all(struct dm_table *t)
1216 struct dm_dev_internal *dd;
1217 struct list_head *devices = dm_table_get_devices(t);
1219 list_for_each_entry(dd, devices, list) {
1220 struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev);
1221 char b[BDEVNAME_SIZE];
1226 DMWARN_LIMIT("%s: Cannot unplug nonexistent device %s",
1227 dm_device_name(t->md),
1228 bdevname(dd->dm_dev.bdev, b));
1232 struct mapped_device *dm_table_get_md(struct dm_table *t)
1239 EXPORT_SYMBOL(dm_vcalloc);
1240 EXPORT_SYMBOL(dm_get_device);
1241 EXPORT_SYMBOL(dm_put_device);
1242 EXPORT_SYMBOL(dm_table_event);
1243 EXPORT_SYMBOL(dm_table_get_size);
1244 EXPORT_SYMBOL(dm_table_get_mode);
1245 EXPORT_SYMBOL(dm_table_get_md);
1246 EXPORT_SYMBOL(dm_table_put);
1247 EXPORT_SYMBOL(dm_table_get);
1248 EXPORT_SYMBOL(dm_table_unplug_all);