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"
28 #define NODE_SIZE L1_CACHE_BYTES
29 #define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
30 #define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
33 struct mapped_device
*md
;
34 enum dm_queue_mode type
;
38 unsigned int counts
[MAX_DEPTH
]; /* in nodes */
39 sector_t
*index
[MAX_DEPTH
];
41 unsigned int num_targets
;
42 unsigned int num_allocated
;
44 struct dm_target
*targets
;
46 struct target_type
*immutable_target_type
;
48 bool integrity_supported
:1;
51 unsigned integrity_added
:1;
54 * Indicates the rw permissions for the new logical
55 * device. This should be a combination of FMODE_READ
60 /* a list of devices used by this table */
61 struct list_head devices
;
63 /* events get handed up using this callback */
64 void (*event_fn
)(void *);
67 struct dm_md_mempools
*mempools
;
69 struct list_head target_callbacks
;
73 * Similar to ceiling(log_size(n))
75 static unsigned int int_log(unsigned int n
, unsigned int base
)
80 n
= dm_div_up(n
, base
);
88 * Calculate the index of the child node of the n'th node k'th key.
90 static inline unsigned int get_child(unsigned int n
, unsigned int k
)
92 return (n
* CHILDREN_PER_NODE
) + k
;
96 * Return the n'th node of level l from table t.
98 static inline sector_t
*get_node(struct dm_table
*t
,
99 unsigned int l
, unsigned int n
)
101 return t
->index
[l
] + (n
* KEYS_PER_NODE
);
105 * Return the highest key that you could lookup from the n'th
106 * node on level l of the btree.
108 static sector_t
high(struct dm_table
*t
, unsigned int l
, unsigned int n
)
110 for (; l
< t
->depth
- 1; l
++)
111 n
= get_child(n
, CHILDREN_PER_NODE
- 1);
113 if (n
>= t
->counts
[l
])
114 return (sector_t
) - 1;
116 return get_node(t
, l
, n
)[KEYS_PER_NODE
- 1];
120 * Fills in a level of the btree based on the highs of the level
123 static int setup_btree_index(unsigned int l
, struct dm_table
*t
)
128 for (n
= 0U; n
< t
->counts
[l
]; n
++) {
129 node
= get_node(t
, l
, n
);
131 for (k
= 0U; k
< KEYS_PER_NODE
; k
++)
132 node
[k
] = high(t
, l
+ 1, get_child(n
, k
));
138 void *dm_vcalloc(unsigned long nmemb
, unsigned long elem_size
)
144 * Check that we're not going to overflow.
146 if (nmemb
> (ULONG_MAX
/ elem_size
))
149 size
= nmemb
* elem_size
;
150 addr
= vzalloc(size
);
154 EXPORT_SYMBOL(dm_vcalloc
);
157 * highs, and targets are managed as dynamic arrays during a
160 static int alloc_targets(struct dm_table
*t
, unsigned int num
)
163 struct dm_target
*n_targets
;
166 * Allocate both the target array and offset array at once.
167 * Append an empty entry to catch sectors beyond the end of
170 n_highs
= (sector_t
*) dm_vcalloc(num
+ 1, sizeof(struct dm_target
) +
175 n_targets
= (struct dm_target
*) (n_highs
+ num
);
177 memset(n_highs
, -1, sizeof(*n_highs
) * num
);
180 t
->num_allocated
= num
;
182 t
->targets
= n_targets
;
187 int dm_table_create(struct dm_table
**result
, fmode_t mode
,
188 unsigned num_targets
, struct mapped_device
*md
)
190 struct dm_table
*t
= kzalloc(sizeof(*t
), GFP_KERNEL
);
195 INIT_LIST_HEAD(&t
->devices
);
196 INIT_LIST_HEAD(&t
->target_callbacks
);
199 num_targets
= KEYS_PER_NODE
;
201 num_targets
= dm_round_up(num_targets
, KEYS_PER_NODE
);
208 if (alloc_targets(t
, num_targets
)) {
213 t
->type
= DM_TYPE_NONE
;
220 static void free_devices(struct list_head
*devices
, struct mapped_device
*md
)
222 struct list_head
*tmp
, *next
;
224 list_for_each_safe(tmp
, next
, devices
) {
225 struct dm_dev_internal
*dd
=
226 list_entry(tmp
, struct dm_dev_internal
, list
);
227 DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
228 dm_device_name(md
), dd
->dm_dev
->name
);
229 dm_put_table_device(md
, dd
->dm_dev
);
234 void dm_table_destroy(struct dm_table
*t
)
241 /* free the indexes */
243 vfree(t
->index
[t
->depth
- 2]);
245 /* free the targets */
246 for (i
= 0; i
< t
->num_targets
; i
++) {
247 struct dm_target
*tgt
= t
->targets
+ i
;
252 dm_put_target_type(tgt
->type
);
257 /* free the device list */
258 free_devices(&t
->devices
, t
->md
);
260 dm_free_md_mempools(t
->mempools
);
266 * See if we've already got a device in the list.
268 static struct dm_dev_internal
*find_device(struct list_head
*l
, dev_t dev
)
270 struct dm_dev_internal
*dd
;
272 list_for_each_entry (dd
, l
, list
)
273 if (dd
->dm_dev
->bdev
->bd_dev
== dev
)
280 * If possible, this checks an area of a destination device is invalid.
282 static int device_area_is_invalid(struct dm_target
*ti
, struct dm_dev
*dev
,
283 sector_t start
, sector_t len
, void *data
)
285 struct request_queue
*q
;
286 struct queue_limits
*limits
= data
;
287 struct block_device
*bdev
= dev
->bdev
;
289 i_size_read(bdev
->bd_inode
) >> SECTOR_SHIFT
;
290 unsigned short logical_block_size_sectors
=
291 limits
->logical_block_size
>> SECTOR_SHIFT
;
292 char b
[BDEVNAME_SIZE
];
295 * Some devices exist without request functions,
296 * such as loop devices not yet bound to backing files.
297 * Forbid the use of such devices.
299 q
= bdev_get_queue(bdev
);
300 if (!q
|| !q
->make_request_fn
) {
301 DMWARN("%s: %s is not yet initialised: "
302 "start=%llu, len=%llu, dev_size=%llu",
303 dm_device_name(ti
->table
->md
), bdevname(bdev
, b
),
304 (unsigned long long)start
,
305 (unsigned long long)len
,
306 (unsigned long long)dev_size
);
313 if ((start
>= dev_size
) || (start
+ len
> dev_size
)) {
314 DMWARN("%s: %s too small for target: "
315 "start=%llu, len=%llu, dev_size=%llu",
316 dm_device_name(ti
->table
->md
), bdevname(bdev
, b
),
317 (unsigned long long)start
,
318 (unsigned long long)len
,
319 (unsigned long long)dev_size
);
324 * If the target is mapped to zoned block device(s), check
325 * that the zones are not partially mapped.
327 if (bdev_zoned_model(bdev
) != BLK_ZONED_NONE
) {
328 unsigned int zone_sectors
= bdev_zone_sectors(bdev
);
330 if (start
& (zone_sectors
- 1)) {
331 DMWARN("%s: start=%llu not aligned to h/w zone size %u of %s",
332 dm_device_name(ti
->table
->md
),
333 (unsigned long long)start
,
334 zone_sectors
, bdevname(bdev
, b
));
339 * Note: The last zone of a zoned block device may be smaller
340 * than other zones. So for a target mapping the end of a
341 * zoned block device with such a zone, len would not be zone
342 * aligned. We do not allow such last smaller zone to be part
343 * of the mapping here to ensure that mappings with multiple
344 * devices do not end up with a smaller zone in the middle of
347 if (len
& (zone_sectors
- 1)) {
348 DMWARN("%s: len=%llu not aligned to h/w zone size %u of %s",
349 dm_device_name(ti
->table
->md
),
350 (unsigned long long)len
,
351 zone_sectors
, bdevname(bdev
, b
));
356 if (logical_block_size_sectors
<= 1)
359 if (start
& (logical_block_size_sectors
- 1)) {
360 DMWARN("%s: start=%llu not aligned to h/w "
361 "logical block size %u of %s",
362 dm_device_name(ti
->table
->md
),
363 (unsigned long long)start
,
364 limits
->logical_block_size
, bdevname(bdev
, b
));
368 if (len
& (logical_block_size_sectors
- 1)) {
369 DMWARN("%s: len=%llu not aligned to h/w "
370 "logical block size %u of %s",
371 dm_device_name(ti
->table
->md
),
372 (unsigned long long)len
,
373 limits
->logical_block_size
, bdevname(bdev
, b
));
381 * This upgrades the mode on an already open dm_dev, being
382 * careful to leave things as they were if we fail to reopen the
383 * device and not to touch the existing bdev field in case
384 * it is accessed concurrently inside dm_table_any_congested().
386 static int upgrade_mode(struct dm_dev_internal
*dd
, fmode_t new_mode
,
387 struct mapped_device
*md
)
390 struct dm_dev
*old_dev
, *new_dev
;
392 old_dev
= dd
->dm_dev
;
394 r
= dm_get_table_device(md
, dd
->dm_dev
->bdev
->bd_dev
,
395 dd
->dm_dev
->mode
| new_mode
, &new_dev
);
399 dd
->dm_dev
= new_dev
;
400 dm_put_table_device(md
, old_dev
);
406 * Convert the path to a device
408 dev_t
dm_get_dev_t(const char *path
)
411 struct block_device
*bdev
;
413 bdev
= lookup_bdev(path
, 0);
415 dev
= name_to_dev_t(path
);
423 EXPORT_SYMBOL_GPL(dm_get_dev_t
);
426 * Add a device to the list, or just increment the usage count if
427 * it's already present.
429 int dm_get_device(struct dm_target
*ti
, const char *path
, fmode_t mode
,
430 struct dm_dev
**result
)
434 struct dm_dev_internal
*dd
;
435 struct dm_table
*t
= ti
->table
;
439 dev
= dm_get_dev_t(path
);
443 dd
= find_device(&t
->devices
, dev
);
445 dd
= kmalloc(sizeof(*dd
), GFP_KERNEL
);
449 if ((r
= dm_get_table_device(t
->md
, dev
, mode
, &dd
->dm_dev
))) {
454 refcount_set(&dd
->count
, 1);
455 list_add(&dd
->list
, &t
->devices
);
458 } else if (dd
->dm_dev
->mode
!= (mode
| dd
->dm_dev
->mode
)) {
459 r
= upgrade_mode(dd
, mode
, t
->md
);
463 refcount_inc(&dd
->count
);
465 *result
= dd
->dm_dev
;
468 EXPORT_SYMBOL(dm_get_device
);
470 static int dm_set_device_limits(struct dm_target
*ti
, struct dm_dev
*dev
,
471 sector_t start
, sector_t len
, void *data
)
473 struct queue_limits
*limits
= data
;
474 struct block_device
*bdev
= dev
->bdev
;
475 struct request_queue
*q
= bdev_get_queue(bdev
);
476 char b
[BDEVNAME_SIZE
];
479 DMWARN("%s: Cannot set limits for nonexistent device %s",
480 dm_device_name(ti
->table
->md
), bdevname(bdev
, b
));
484 if (bdev_stack_limits(limits
, bdev
, start
) < 0)
485 DMWARN("%s: adding target device %s caused an alignment inconsistency: "
486 "physical_block_size=%u, logical_block_size=%u, "
487 "alignment_offset=%u, start=%llu",
488 dm_device_name(ti
->table
->md
), bdevname(bdev
, b
),
489 q
->limits
.physical_block_size
,
490 q
->limits
.logical_block_size
,
491 q
->limits
.alignment_offset
,
492 (unsigned long long) start
<< SECTOR_SHIFT
);
494 limits
->zoned
= blk_queue_zoned_model(q
);
500 * Decrement a device's use count and remove it if necessary.
502 void dm_put_device(struct dm_target
*ti
, struct dm_dev
*d
)
505 struct list_head
*devices
= &ti
->table
->devices
;
506 struct dm_dev_internal
*dd
;
508 list_for_each_entry(dd
, devices
, list
) {
509 if (dd
->dm_dev
== d
) {
515 DMWARN("%s: device %s not in table devices list",
516 dm_device_name(ti
->table
->md
), d
->name
);
519 if (refcount_dec_and_test(&dd
->count
)) {
520 dm_put_table_device(ti
->table
->md
, d
);
525 EXPORT_SYMBOL(dm_put_device
);
528 * Checks to see if the target joins onto the end of the table.
530 static int adjoin(struct dm_table
*table
, struct dm_target
*ti
)
532 struct dm_target
*prev
;
534 if (!table
->num_targets
)
537 prev
= &table
->targets
[table
->num_targets
- 1];
538 return (ti
->begin
== (prev
->begin
+ prev
->len
));
542 * Used to dynamically allocate the arg array.
544 * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
545 * process messages even if some device is suspended. These messages have a
546 * small fixed number of arguments.
548 * On the other hand, dm-switch needs to process bulk data using messages and
549 * excessive use of GFP_NOIO could cause trouble.
551 static char **realloc_argv(unsigned *array_size
, char **old_argv
)
558 new_size
= *array_size
* 2;
564 argv
= kmalloc(new_size
* sizeof(*argv
), gfp
);
566 memcpy(argv
, old_argv
, *array_size
* sizeof(*argv
));
567 *array_size
= new_size
;
575 * Destructively splits up the argument list to pass to ctr.
577 int dm_split_args(int *argc
, char ***argvp
, char *input
)
579 char *start
, *end
= input
, *out
, **argv
= NULL
;
580 unsigned array_size
= 0;
589 argv
= realloc_argv(&array_size
, argv
);
594 /* Skip whitespace */
595 start
= skip_spaces(end
);
598 break; /* success, we hit the end */
600 /* 'out' is used to remove any back-quotes */
603 /* Everything apart from '\0' can be quoted */
604 if (*end
== '\\' && *(end
+ 1)) {
611 break; /* end of token */
616 /* have we already filled the array ? */
617 if ((*argc
+ 1) > array_size
) {
618 argv
= realloc_argv(&array_size
, argv
);
623 /* we know this is whitespace */
627 /* terminate the string and put it in the array */
638 * Impose necessary and sufficient conditions on a devices's table such
639 * that any incoming bio which respects its logical_block_size can be
640 * processed successfully. If it falls across the boundary between
641 * two or more targets, the size of each piece it gets split into must
642 * be compatible with the logical_block_size of the target processing it.
644 static int validate_hardware_logical_block_alignment(struct dm_table
*table
,
645 struct queue_limits
*limits
)
648 * This function uses arithmetic modulo the logical_block_size
649 * (in units of 512-byte sectors).
651 unsigned short device_logical_block_size_sects
=
652 limits
->logical_block_size
>> SECTOR_SHIFT
;
655 * Offset of the start of the next table entry, mod logical_block_size.
657 unsigned short next_target_start
= 0;
660 * Given an aligned bio that extends beyond the end of a
661 * target, how many sectors must the next target handle?
663 unsigned short remaining
= 0;
665 struct dm_target
*uninitialized_var(ti
);
666 struct queue_limits ti_limits
;
670 * Check each entry in the table in turn.
672 for (i
= 0; i
< dm_table_get_num_targets(table
); i
++) {
673 ti
= dm_table_get_target(table
, i
);
675 blk_set_stacking_limits(&ti_limits
);
677 /* combine all target devices' limits */
678 if (ti
->type
->iterate_devices
)
679 ti
->type
->iterate_devices(ti
, dm_set_device_limits
,
683 * If the remaining sectors fall entirely within this
684 * table entry are they compatible with its logical_block_size?
686 if (remaining
< ti
->len
&&
687 remaining
& ((ti_limits
.logical_block_size
>>
692 (unsigned short) ((next_target_start
+ ti
->len
) &
693 (device_logical_block_size_sects
- 1));
694 remaining
= next_target_start
?
695 device_logical_block_size_sects
- next_target_start
: 0;
699 DMWARN("%s: table line %u (start sect %llu len %llu) "
700 "not aligned to h/w logical block size %u",
701 dm_device_name(table
->md
), i
,
702 (unsigned long long) ti
->begin
,
703 (unsigned long long) ti
->len
,
704 limits
->logical_block_size
);
711 int dm_table_add_target(struct dm_table
*t
, const char *type
,
712 sector_t start
, sector_t len
, char *params
)
714 int r
= -EINVAL
, argc
;
716 struct dm_target
*tgt
;
719 DMERR("%s: target type %s must appear alone in table",
720 dm_device_name(t
->md
), t
->targets
->type
->name
);
724 BUG_ON(t
->num_targets
>= t
->num_allocated
);
726 tgt
= t
->targets
+ t
->num_targets
;
727 memset(tgt
, 0, sizeof(*tgt
));
730 DMERR("%s: zero-length target", dm_device_name(t
->md
));
734 tgt
->type
= dm_get_target_type(type
);
736 DMERR("%s: %s: unknown target type", dm_device_name(t
->md
), type
);
740 if (dm_target_needs_singleton(tgt
->type
)) {
741 if (t
->num_targets
) {
742 tgt
->error
= "singleton target type must appear alone in table";
748 if (dm_target_always_writeable(tgt
->type
) && !(t
->mode
& FMODE_WRITE
)) {
749 tgt
->error
= "target type may not be included in a read-only table";
753 if (t
->immutable_target_type
) {
754 if (t
->immutable_target_type
!= tgt
->type
) {
755 tgt
->error
= "immutable target type cannot be mixed with other target types";
758 } else if (dm_target_is_immutable(tgt
->type
)) {
759 if (t
->num_targets
) {
760 tgt
->error
= "immutable target type cannot be mixed with other target types";
763 t
->immutable_target_type
= tgt
->type
;
766 if (dm_target_has_integrity(tgt
->type
))
767 t
->integrity_added
= 1;
772 tgt
->error
= "Unknown error";
775 * Does this target adjoin the previous one ?
777 if (!adjoin(t
, tgt
)) {
778 tgt
->error
= "Gap in table";
782 r
= dm_split_args(&argc
, &argv
, params
);
784 tgt
->error
= "couldn't split parameters (insufficient memory)";
788 r
= tgt
->type
->ctr(tgt
, argc
, argv
);
793 t
->highs
[t
->num_targets
++] = tgt
->begin
+ tgt
->len
- 1;
795 if (!tgt
->num_discard_bios
&& tgt
->discards_supported
)
796 DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
797 dm_device_name(t
->md
), type
);
802 DMERR("%s: %s: %s", dm_device_name(t
->md
), type
, tgt
->error
);
803 dm_put_target_type(tgt
->type
);
808 * Target argument parsing helpers.
810 static int validate_next_arg(const struct dm_arg
*arg
,
811 struct dm_arg_set
*arg_set
,
812 unsigned *value
, char **error
, unsigned grouped
)
814 const char *arg_str
= dm_shift_arg(arg_set
);
818 (sscanf(arg_str
, "%u%c", value
, &dummy
) != 1) ||
819 (*value
< arg
->min
) ||
820 (*value
> arg
->max
) ||
821 (grouped
&& arg_set
->argc
< *value
)) {
829 int dm_read_arg(const struct dm_arg
*arg
, struct dm_arg_set
*arg_set
,
830 unsigned *value
, char **error
)
832 return validate_next_arg(arg
, arg_set
, value
, error
, 0);
834 EXPORT_SYMBOL(dm_read_arg
);
836 int dm_read_arg_group(const struct dm_arg
*arg
, struct dm_arg_set
*arg_set
,
837 unsigned *value
, char **error
)
839 return validate_next_arg(arg
, arg_set
, value
, error
, 1);
841 EXPORT_SYMBOL(dm_read_arg_group
);
843 const char *dm_shift_arg(struct dm_arg_set
*as
)
856 EXPORT_SYMBOL(dm_shift_arg
);
858 void dm_consume_args(struct dm_arg_set
*as
, unsigned num_args
)
860 BUG_ON(as
->argc
< num_args
);
861 as
->argc
-= num_args
;
862 as
->argv
+= num_args
;
864 EXPORT_SYMBOL(dm_consume_args
);
866 static bool __table_type_bio_based(enum dm_queue_mode table_type
)
868 return (table_type
== DM_TYPE_BIO_BASED
||
869 table_type
== DM_TYPE_DAX_BIO_BASED
);
872 static bool __table_type_request_based(enum dm_queue_mode table_type
)
874 return (table_type
== DM_TYPE_REQUEST_BASED
||
875 table_type
== DM_TYPE_MQ_REQUEST_BASED
);
878 void dm_table_set_type(struct dm_table
*t
, enum dm_queue_mode type
)
882 EXPORT_SYMBOL_GPL(dm_table_set_type
);
884 static int device_supports_dax(struct dm_target
*ti
, struct dm_dev
*dev
,
885 sector_t start
, sector_t len
, void *data
)
887 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
889 return q
&& blk_queue_dax(q
);
892 static bool dm_table_supports_dax(struct dm_table
*t
)
894 struct dm_target
*ti
;
897 /* Ensure that all targets support DAX. */
898 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
899 ti
= dm_table_get_target(t
, i
);
901 if (!ti
->type
->direct_access
)
904 if (!ti
->type
->iterate_devices
||
905 !ti
->type
->iterate_devices(ti
, device_supports_dax
, NULL
))
912 static int dm_table_determine_type(struct dm_table
*t
)
915 unsigned bio_based
= 0, request_based
= 0, hybrid
= 0;
916 unsigned sq_count
= 0, mq_count
= 0;
917 struct dm_target
*tgt
;
918 struct dm_dev_internal
*dd
;
919 struct list_head
*devices
= dm_table_get_devices(t
);
920 enum dm_queue_mode live_md_type
= dm_get_md_type(t
->md
);
922 if (t
->type
!= DM_TYPE_NONE
) {
923 /* target already set the table's type */
924 if (t
->type
== DM_TYPE_BIO_BASED
)
926 BUG_ON(t
->type
== DM_TYPE_DAX_BIO_BASED
);
927 goto verify_rq_based
;
930 for (i
= 0; i
< t
->num_targets
; i
++) {
931 tgt
= t
->targets
+ i
;
932 if (dm_target_hybrid(tgt
))
934 else if (dm_target_request_based(tgt
))
939 if (bio_based
&& request_based
) {
940 DMWARN("Inconsistent table: different target types"
941 " can't be mixed up");
946 if (hybrid
&& !bio_based
&& !request_based
) {
948 * The targets can work either way.
949 * Determine the type from the live device.
950 * Default to bio-based if device is new.
952 if (__table_type_request_based(live_md_type
))
959 /* We must use this table as bio-based */
960 t
->type
= DM_TYPE_BIO_BASED
;
961 if (dm_table_supports_dax(t
) ||
962 (list_empty(devices
) && live_md_type
== DM_TYPE_DAX_BIO_BASED
))
963 t
->type
= DM_TYPE_DAX_BIO_BASED
;
967 BUG_ON(!request_based
); /* No targets in this table */
970 * The only way to establish DM_TYPE_MQ_REQUEST_BASED is by
971 * having a compatible target use dm_table_set_type.
973 t
->type
= DM_TYPE_REQUEST_BASED
;
977 * Request-based dm supports only tables that have a single target now.
978 * To support multiple targets, request splitting support is needed,
979 * and that needs lots of changes in the block-layer.
980 * (e.g. request completion process for partial completion.)
982 if (t
->num_targets
> 1) {
983 DMWARN("Request-based dm doesn't support multiple targets yet");
987 if (list_empty(devices
)) {
989 struct dm_table
*live_table
= dm_get_live_table(t
->md
, &srcu_idx
);
991 /* inherit live table's type and all_blk_mq */
993 t
->type
= live_table
->type
;
994 t
->all_blk_mq
= live_table
->all_blk_mq
;
996 dm_put_live_table(t
->md
, srcu_idx
);
1000 /* Non-request-stackable devices can't be used for request-based dm */
1001 list_for_each_entry(dd
, devices
, list
) {
1002 struct request_queue
*q
= bdev_get_queue(dd
->dm_dev
->bdev
);
1004 if (!queue_is_rq_based(q
)) {
1005 DMERR("table load rejected: including"
1006 " non-request-stackable devices");
1015 if (sq_count
&& mq_count
) {
1016 DMERR("table load rejected: not all devices are blk-mq request-stackable");
1019 t
->all_blk_mq
= mq_count
> 0;
1021 if (t
->type
== DM_TYPE_MQ_REQUEST_BASED
&& !t
->all_blk_mq
) {
1022 DMERR("table load rejected: all devices are not blk-mq request-stackable");
1029 enum dm_queue_mode
dm_table_get_type(struct dm_table
*t
)
1034 struct target_type
*dm_table_get_immutable_target_type(struct dm_table
*t
)
1036 return t
->immutable_target_type
;
1039 struct dm_target
*dm_table_get_immutable_target(struct dm_table
*t
)
1041 /* Immutable target is implicitly a singleton */
1042 if (t
->num_targets
> 1 ||
1043 !dm_target_is_immutable(t
->targets
[0].type
))
1049 struct dm_target
*dm_table_get_wildcard_target(struct dm_table
*t
)
1051 struct dm_target
*ti
;
1054 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1055 ti
= dm_table_get_target(t
, i
);
1056 if (dm_target_is_wildcard(ti
->type
))
1063 bool dm_table_bio_based(struct dm_table
*t
)
1065 return __table_type_bio_based(dm_table_get_type(t
));
1068 bool dm_table_request_based(struct dm_table
*t
)
1070 return __table_type_request_based(dm_table_get_type(t
));
1073 bool dm_table_all_blk_mq_devices(struct dm_table
*t
)
1075 return t
->all_blk_mq
;
1078 static int dm_table_alloc_md_mempools(struct dm_table
*t
, struct mapped_device
*md
)
1080 enum dm_queue_mode type
= dm_table_get_type(t
);
1081 unsigned per_io_data_size
= 0;
1082 struct dm_target
*tgt
;
1085 if (unlikely(type
== DM_TYPE_NONE
)) {
1086 DMWARN("no table type is set, can't allocate mempools");
1090 if (__table_type_bio_based(type
))
1091 for (i
= 0; i
< t
->num_targets
; i
++) {
1092 tgt
= t
->targets
+ i
;
1093 per_io_data_size
= max(per_io_data_size
, tgt
->per_io_data_size
);
1096 t
->mempools
= dm_alloc_md_mempools(md
, type
, t
->integrity_supported
, per_io_data_size
);
1103 void dm_table_free_md_mempools(struct dm_table
*t
)
1105 dm_free_md_mempools(t
->mempools
);
1109 struct dm_md_mempools
*dm_table_get_md_mempools(struct dm_table
*t
)
1114 static int setup_indexes(struct dm_table
*t
)
1117 unsigned int total
= 0;
1120 /* allocate the space for *all* the indexes */
1121 for (i
= t
->depth
- 2; i
>= 0; i
--) {
1122 t
->counts
[i
] = dm_div_up(t
->counts
[i
+ 1], CHILDREN_PER_NODE
);
1123 total
+= t
->counts
[i
];
1126 indexes
= (sector_t
*) dm_vcalloc(total
, (unsigned long) NODE_SIZE
);
1130 /* set up internal nodes, bottom-up */
1131 for (i
= t
->depth
- 2; i
>= 0; i
--) {
1132 t
->index
[i
] = indexes
;
1133 indexes
+= (KEYS_PER_NODE
* t
->counts
[i
]);
1134 setup_btree_index(i
, t
);
1141 * Builds the btree to index the map.
1143 static int dm_table_build_index(struct dm_table
*t
)
1146 unsigned int leaf_nodes
;
1148 /* how many indexes will the btree have ? */
1149 leaf_nodes
= dm_div_up(t
->num_targets
, KEYS_PER_NODE
);
1150 t
->depth
= 1 + int_log(leaf_nodes
, CHILDREN_PER_NODE
);
1152 /* leaf layer has already been set up */
1153 t
->counts
[t
->depth
- 1] = leaf_nodes
;
1154 t
->index
[t
->depth
- 1] = t
->highs
;
1157 r
= setup_indexes(t
);
1162 static bool integrity_profile_exists(struct gendisk
*disk
)
1164 return !!blk_get_integrity(disk
);
1168 * Get a disk whose integrity profile reflects the table's profile.
1169 * Returns NULL if integrity support was inconsistent or unavailable.
1171 static struct gendisk
* dm_table_get_integrity_disk(struct dm_table
*t
)
1173 struct list_head
*devices
= dm_table_get_devices(t
);
1174 struct dm_dev_internal
*dd
= NULL
;
1175 struct gendisk
*prev_disk
= NULL
, *template_disk
= NULL
;
1178 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1179 struct dm_target
*ti
= dm_table_get_target(t
, i
);
1180 if (!dm_target_passes_integrity(ti
->type
))
1184 list_for_each_entry(dd
, devices
, list
) {
1185 template_disk
= dd
->dm_dev
->bdev
->bd_disk
;
1186 if (!integrity_profile_exists(template_disk
))
1188 else if (prev_disk
&&
1189 blk_integrity_compare(prev_disk
, template_disk
) < 0)
1191 prev_disk
= template_disk
;
1194 return template_disk
;
1198 DMWARN("%s: integrity not set: %s and %s profile mismatch",
1199 dm_device_name(t
->md
),
1200 prev_disk
->disk_name
,
1201 template_disk
->disk_name
);
1206 * Register the mapped device for blk_integrity support if the
1207 * underlying devices have an integrity profile. But all devices may
1208 * not have matching profiles (checking all devices isn't reliable
1209 * during table load because this table may use other DM device(s) which
1210 * must be resumed before they will have an initialized integity
1211 * profile). Consequently, stacked DM devices force a 2 stage integrity
1212 * profile validation: First pass during table load, final pass during
1215 static int dm_table_register_integrity(struct dm_table
*t
)
1217 struct mapped_device
*md
= t
->md
;
1218 struct gendisk
*template_disk
= NULL
;
1220 /* If target handles integrity itself do not register it here. */
1221 if (t
->integrity_added
)
1224 template_disk
= dm_table_get_integrity_disk(t
);
1228 if (!integrity_profile_exists(dm_disk(md
))) {
1229 t
->integrity_supported
= true;
1231 * Register integrity profile during table load; we can do
1232 * this because the final profile must match during resume.
1234 blk_integrity_register(dm_disk(md
),
1235 blk_get_integrity(template_disk
));
1240 * If DM device already has an initialized integrity
1241 * profile the new profile should not conflict.
1243 if (blk_integrity_compare(dm_disk(md
), template_disk
) < 0) {
1244 DMWARN("%s: conflict with existing integrity profile: "
1245 "%s profile mismatch",
1246 dm_device_name(t
->md
),
1247 template_disk
->disk_name
);
1251 /* Preserve existing integrity profile */
1252 t
->integrity_supported
= true;
1257 * Prepares the table for use by building the indices,
1258 * setting the type, and allocating mempools.
1260 int dm_table_complete(struct dm_table
*t
)
1264 r
= dm_table_determine_type(t
);
1266 DMERR("unable to determine table type");
1270 r
= dm_table_build_index(t
);
1272 DMERR("unable to build btrees");
1276 r
= dm_table_register_integrity(t
);
1278 DMERR("could not register integrity profile.");
1282 r
= dm_table_alloc_md_mempools(t
, t
->md
);
1284 DMERR("unable to allocate mempools");
1289 static DEFINE_MUTEX(_event_lock
);
1290 void dm_table_event_callback(struct dm_table
*t
,
1291 void (*fn
)(void *), void *context
)
1293 mutex_lock(&_event_lock
);
1295 t
->event_context
= context
;
1296 mutex_unlock(&_event_lock
);
1299 void dm_table_event(struct dm_table
*t
)
1302 * You can no longer call dm_table_event() from interrupt
1303 * context, use a bottom half instead.
1305 BUG_ON(in_interrupt());
1307 mutex_lock(&_event_lock
);
1309 t
->event_fn(t
->event_context
);
1310 mutex_unlock(&_event_lock
);
1312 EXPORT_SYMBOL(dm_table_event
);
1314 sector_t
dm_table_get_size(struct dm_table
*t
)
1316 return t
->num_targets
? (t
->highs
[t
->num_targets
- 1] + 1) : 0;
1318 EXPORT_SYMBOL(dm_table_get_size
);
1320 struct dm_target
*dm_table_get_target(struct dm_table
*t
, unsigned int index
)
1322 if (index
>= t
->num_targets
)
1325 return t
->targets
+ index
;
1329 * Search the btree for the correct target.
1331 * Caller should check returned pointer with dm_target_is_valid()
1332 * to trap I/O beyond end of device.
1334 struct dm_target
*dm_table_find_target(struct dm_table
*t
, sector_t sector
)
1336 unsigned int l
, n
= 0, k
= 0;
1339 for (l
= 0; l
< t
->depth
; l
++) {
1340 n
= get_child(n
, k
);
1341 node
= get_node(t
, l
, n
);
1343 for (k
= 0; k
< KEYS_PER_NODE
; k
++)
1344 if (node
[k
] >= sector
)
1348 return &t
->targets
[(KEYS_PER_NODE
* n
) + k
];
1351 static int count_device(struct dm_target
*ti
, struct dm_dev
*dev
,
1352 sector_t start
, sector_t len
, void *data
)
1354 unsigned *num_devices
= data
;
1362 * Check whether a table has no data devices attached using each
1363 * target's iterate_devices method.
1364 * Returns false if the result is unknown because a target doesn't
1365 * support iterate_devices.
1367 bool dm_table_has_no_data_devices(struct dm_table
*table
)
1369 struct dm_target
*ti
;
1370 unsigned i
, num_devices
;
1372 for (i
= 0; i
< dm_table_get_num_targets(table
); i
++) {
1373 ti
= dm_table_get_target(table
, i
);
1375 if (!ti
->type
->iterate_devices
)
1379 ti
->type
->iterate_devices(ti
, count_device
, &num_devices
);
1387 static int device_is_zoned_model(struct dm_target
*ti
, struct dm_dev
*dev
,
1388 sector_t start
, sector_t len
, void *data
)
1390 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1391 enum blk_zoned_model
*zoned_model
= data
;
1393 return q
&& blk_queue_zoned_model(q
) == *zoned_model
;
1396 static bool dm_table_supports_zoned_model(struct dm_table
*t
,
1397 enum blk_zoned_model zoned_model
)
1399 struct dm_target
*ti
;
1402 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1403 ti
= dm_table_get_target(t
, i
);
1405 if (zoned_model
== BLK_ZONED_HM
&&
1406 !dm_target_supports_zoned_hm(ti
->type
))
1409 if (!ti
->type
->iterate_devices
||
1410 !ti
->type
->iterate_devices(ti
, device_is_zoned_model
, &zoned_model
))
1417 static int device_matches_zone_sectors(struct dm_target
*ti
, struct dm_dev
*dev
,
1418 sector_t start
, sector_t len
, void *data
)
1420 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1421 unsigned int *zone_sectors
= data
;
1423 return q
&& blk_queue_zone_sectors(q
) == *zone_sectors
;
1426 static bool dm_table_matches_zone_sectors(struct dm_table
*t
,
1427 unsigned int zone_sectors
)
1429 struct dm_target
*ti
;
1432 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1433 ti
= dm_table_get_target(t
, i
);
1435 if (!ti
->type
->iterate_devices
||
1436 !ti
->type
->iterate_devices(ti
, device_matches_zone_sectors
, &zone_sectors
))
1443 static int validate_hardware_zoned_model(struct dm_table
*table
,
1444 enum blk_zoned_model zoned_model
,
1445 unsigned int zone_sectors
)
1447 if (zoned_model
== BLK_ZONED_NONE
)
1450 if (!dm_table_supports_zoned_model(table
, zoned_model
)) {
1451 DMERR("%s: zoned model is not consistent across all devices",
1452 dm_device_name(table
->md
));
1456 /* Check zone size validity and compatibility */
1457 if (!zone_sectors
|| !is_power_of_2(zone_sectors
))
1460 if (!dm_table_matches_zone_sectors(table
, zone_sectors
)) {
1461 DMERR("%s: zone sectors is not consistent across all devices",
1462 dm_device_name(table
->md
));
1470 * Establish the new table's queue_limits and validate them.
1472 int dm_calculate_queue_limits(struct dm_table
*table
,
1473 struct queue_limits
*limits
)
1475 struct dm_target
*ti
;
1476 struct queue_limits ti_limits
;
1478 enum blk_zoned_model zoned_model
= BLK_ZONED_NONE
;
1479 unsigned int zone_sectors
= 0;
1481 blk_set_stacking_limits(limits
);
1483 for (i
= 0; i
< dm_table_get_num_targets(table
); i
++) {
1484 blk_set_stacking_limits(&ti_limits
);
1486 ti
= dm_table_get_target(table
, i
);
1488 if (!ti
->type
->iterate_devices
)
1489 goto combine_limits
;
1492 * Combine queue limits of all the devices this target uses.
1494 ti
->type
->iterate_devices(ti
, dm_set_device_limits
,
1497 if (zoned_model
== BLK_ZONED_NONE
&& ti_limits
.zoned
!= BLK_ZONED_NONE
) {
1499 * After stacking all limits, validate all devices
1500 * in table support this zoned model and zone sectors.
1502 zoned_model
= ti_limits
.zoned
;
1503 zone_sectors
= ti_limits
.chunk_sectors
;
1506 /* Set I/O hints portion of queue limits */
1507 if (ti
->type
->io_hints
)
1508 ti
->type
->io_hints(ti
, &ti_limits
);
1511 * Check each device area is consistent with the target's
1512 * overall queue limits.
1514 if (ti
->type
->iterate_devices(ti
, device_area_is_invalid
,
1520 * Merge this target's queue limits into the overall limits
1523 if (blk_stack_limits(limits
, &ti_limits
, 0) < 0)
1524 DMWARN("%s: adding target device "
1525 "(start sect %llu len %llu) "
1526 "caused an alignment inconsistency",
1527 dm_device_name(table
->md
),
1528 (unsigned long long) ti
->begin
,
1529 (unsigned long long) ti
->len
);
1532 * FIXME: this should likely be moved to blk_stack_limits(), would
1533 * also eliminate limits->zoned stacking hack in dm_set_device_limits()
1535 if (limits
->zoned
== BLK_ZONED_NONE
&& ti_limits
.zoned
!= BLK_ZONED_NONE
) {
1537 * By default, the stacked limits zoned model is set to
1538 * BLK_ZONED_NONE in blk_set_stacking_limits(). Update
1539 * this model using the first target model reported
1540 * that is not BLK_ZONED_NONE. This will be either the
1541 * first target device zoned model or the model reported
1542 * by the target .io_hints.
1544 limits
->zoned
= ti_limits
.zoned
;
1549 * Verify that the zoned model and zone sectors, as determined before
1550 * any .io_hints override, are the same across all devices in the table.
1551 * - this is especially relevant if .io_hints is emulating a disk-managed
1552 * zoned model (aka BLK_ZONED_NONE) on host-managed zoned block devices.
1555 if (limits
->zoned
!= BLK_ZONED_NONE
) {
1557 * ...IF the above limits stacking determined a zoned model
1558 * validate that all of the table's devices conform to it.
1560 zoned_model
= limits
->zoned
;
1561 zone_sectors
= limits
->chunk_sectors
;
1563 if (validate_hardware_zoned_model(table
, zoned_model
, zone_sectors
))
1566 return validate_hardware_logical_block_alignment(table
, limits
);
1570 * Verify that all devices have an integrity profile that matches the
1571 * DM device's registered integrity profile. If the profiles don't
1572 * match then unregister the DM device's integrity profile.
1574 static void dm_table_verify_integrity(struct dm_table
*t
)
1576 struct gendisk
*template_disk
= NULL
;
1578 if (t
->integrity_added
)
1581 if (t
->integrity_supported
) {
1583 * Verify that the original integrity profile
1584 * matches all the devices in this table.
1586 template_disk
= dm_table_get_integrity_disk(t
);
1587 if (template_disk
&&
1588 blk_integrity_compare(dm_disk(t
->md
), template_disk
) >= 0)
1592 if (integrity_profile_exists(dm_disk(t
->md
))) {
1593 DMWARN("%s: unable to establish an integrity profile",
1594 dm_device_name(t
->md
));
1595 blk_integrity_unregister(dm_disk(t
->md
));
1599 static int device_flush_capable(struct dm_target
*ti
, struct dm_dev
*dev
,
1600 sector_t start
, sector_t len
, void *data
)
1602 unsigned long flush
= (unsigned long) data
;
1603 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1605 return q
&& (q
->queue_flags
& flush
);
1608 static bool dm_table_supports_flush(struct dm_table
*t
, unsigned long flush
)
1610 struct dm_target
*ti
;
1614 * Require at least one underlying device to support flushes.
1615 * t->devices includes internal dm devices such as mirror logs
1616 * so we need to use iterate_devices here, which targets
1617 * supporting flushes must provide.
1619 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1620 ti
= dm_table_get_target(t
, i
);
1622 if (!ti
->num_flush_bios
)
1625 if (ti
->flush_supported
)
1628 if (ti
->type
->iterate_devices
&&
1629 ti
->type
->iterate_devices(ti
, device_flush_capable
, (void *) flush
))
1636 static int device_dax_write_cache_enabled(struct dm_target
*ti
,
1637 struct dm_dev
*dev
, sector_t start
,
1638 sector_t len
, void *data
)
1640 struct dax_device
*dax_dev
= dev
->dax_dev
;
1645 if (dax_write_cache_enabled(dax_dev
))
1650 static int dm_table_supports_dax_write_cache(struct dm_table
*t
)
1652 struct dm_target
*ti
;
1655 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1656 ti
= dm_table_get_target(t
, i
);
1658 if (ti
->type
->iterate_devices
&&
1659 ti
->type
->iterate_devices(ti
,
1660 device_dax_write_cache_enabled
, NULL
))
1667 static int device_is_nonrot(struct dm_target
*ti
, struct dm_dev
*dev
,
1668 sector_t start
, sector_t len
, void *data
)
1670 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1672 return q
&& blk_queue_nonrot(q
);
1675 static int device_is_not_random(struct dm_target
*ti
, struct dm_dev
*dev
,
1676 sector_t start
, sector_t len
, void *data
)
1678 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1680 return q
&& !blk_queue_add_random(q
);
1683 static int queue_supports_sg_merge(struct dm_target
*ti
, struct dm_dev
*dev
,
1684 sector_t start
, sector_t len
, void *data
)
1686 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1688 return q
&& !test_bit(QUEUE_FLAG_NO_SG_MERGE
, &q
->queue_flags
);
1691 static bool dm_table_all_devices_attribute(struct dm_table
*t
,
1692 iterate_devices_callout_fn func
)
1694 struct dm_target
*ti
;
1697 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1698 ti
= dm_table_get_target(t
, i
);
1700 if (!ti
->type
->iterate_devices
||
1701 !ti
->type
->iterate_devices(ti
, func
, NULL
))
1708 static int device_not_write_same_capable(struct dm_target
*ti
, struct dm_dev
*dev
,
1709 sector_t start
, sector_t len
, void *data
)
1711 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1713 return q
&& !q
->limits
.max_write_same_sectors
;
1716 static bool dm_table_supports_write_same(struct dm_table
*t
)
1718 struct dm_target
*ti
;
1721 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1722 ti
= dm_table_get_target(t
, i
);
1724 if (!ti
->num_write_same_bios
)
1727 if (!ti
->type
->iterate_devices
||
1728 ti
->type
->iterate_devices(ti
, device_not_write_same_capable
, NULL
))
1735 static int device_not_write_zeroes_capable(struct dm_target
*ti
, struct dm_dev
*dev
,
1736 sector_t start
, sector_t len
, void *data
)
1738 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1740 return q
&& !q
->limits
.max_write_zeroes_sectors
;
1743 static bool dm_table_supports_write_zeroes(struct dm_table
*t
)
1745 struct dm_target
*ti
;
1748 while (i
< dm_table_get_num_targets(t
)) {
1749 ti
= dm_table_get_target(t
, i
++);
1751 if (!ti
->num_write_zeroes_bios
)
1754 if (!ti
->type
->iterate_devices
||
1755 ti
->type
->iterate_devices(ti
, device_not_write_zeroes_capable
, NULL
))
1762 static int device_not_discard_capable(struct dm_target
*ti
, struct dm_dev
*dev
,
1763 sector_t start
, sector_t len
, void *data
)
1765 struct request_queue
*q
= bdev_get_queue(dev
->bdev
);
1767 return q
&& !blk_queue_discard(q
);
1770 static bool dm_table_supports_discards(struct dm_table
*t
)
1772 struct dm_target
*ti
;
1775 for (i
= 0; i
< dm_table_get_num_targets(t
); i
++) {
1776 ti
= dm_table_get_target(t
, i
);
1778 if (!ti
->num_discard_bios
)
1782 * Either the target provides discard support (as implied by setting
1783 * 'discards_supported') or it relies on _all_ data devices having
1786 if (!ti
->discards_supported
&&
1787 (!ti
->type
->iterate_devices
||
1788 ti
->type
->iterate_devices(ti
, device_not_discard_capable
, NULL
)))
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;
1801 * Copy table's limits to the DM device's request_queue
1803 q
->limits
= *limits
;
1805 if (!dm_table_supports_discards(t
)) {
1806 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
, q
);
1807 /* Must also clear discard limits... */
1808 q
->limits
.max_discard_sectors
= 0;
1809 q
->limits
.max_hw_discard_sectors
= 0;
1810 q
->limits
.discard_granularity
= 0;
1811 q
->limits
.discard_alignment
= 0;
1812 q
->limits
.discard_misaligned
= 0;
1814 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
, q
);
1816 if (dm_table_supports_flush(t
, (1UL << QUEUE_FLAG_WC
))) {
1818 if (dm_table_supports_flush(t
, (1UL << QUEUE_FLAG_FUA
)))
1821 blk_queue_write_cache(q
, wc
, fua
);
1823 if (dm_table_supports_dax(t
))
1824 queue_flag_set_unlocked(QUEUE_FLAG_DAX
, q
);
1825 if (dm_table_supports_dax_write_cache(t
))
1826 dax_write_cache(t
->md
->dax_dev
, true);
1828 /* Ensure that all underlying devices are non-rotational. */
1829 if (dm_table_all_devices_attribute(t
, device_is_nonrot
))
1830 queue_flag_set_unlocked(QUEUE_FLAG_NONROT
, q
);
1832 queue_flag_clear_unlocked(QUEUE_FLAG_NONROT
, q
);
1834 if (!dm_table_supports_write_same(t
))
1835 q
->limits
.max_write_same_sectors
= 0;
1836 if (!dm_table_supports_write_zeroes(t
))
1837 q
->limits
.max_write_zeroes_sectors
= 0;
1839 if (dm_table_all_devices_attribute(t
, queue_supports_sg_merge
))
1840 queue_flag_clear_unlocked(QUEUE_FLAG_NO_SG_MERGE
, q
);
1842 queue_flag_set_unlocked(QUEUE_FLAG_NO_SG_MERGE
, q
);
1844 dm_table_verify_integrity(t
);
1847 * Determine whether or not this queue's I/O timings contribute
1848 * to the entropy pool, Only request-based targets use this.
1849 * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
1852 if (blk_queue_add_random(q
) && dm_table_all_devices_attribute(t
, device_is_not_random
))
1853 queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM
, q
);
1856 unsigned int dm_table_get_num_targets(struct dm_table
*t
)
1858 return t
->num_targets
;
1861 struct list_head
*dm_table_get_devices(struct dm_table
*t
)
1866 fmode_t
dm_table_get_mode(struct dm_table
*t
)
1870 EXPORT_SYMBOL(dm_table_get_mode
);
1878 static void suspend_targets(struct dm_table
*t
, enum suspend_mode mode
)
1880 int i
= t
->num_targets
;
1881 struct dm_target
*ti
= t
->targets
;
1883 lockdep_assert_held(&t
->md
->suspend_lock
);
1888 if (ti
->type
->presuspend
)
1889 ti
->type
->presuspend(ti
);
1891 case PRESUSPEND_UNDO
:
1892 if (ti
->type
->presuspend_undo
)
1893 ti
->type
->presuspend_undo(ti
);
1896 if (ti
->type
->postsuspend
)
1897 ti
->type
->postsuspend(ti
);
1904 void dm_table_presuspend_targets(struct dm_table
*t
)
1909 suspend_targets(t
, PRESUSPEND
);
1912 void dm_table_presuspend_undo_targets(struct dm_table
*t
)
1917 suspend_targets(t
, PRESUSPEND_UNDO
);
1920 void dm_table_postsuspend_targets(struct dm_table
*t
)
1925 suspend_targets(t
, POSTSUSPEND
);
1928 int dm_table_resume_targets(struct dm_table
*t
)
1932 lockdep_assert_held(&t
->md
->suspend_lock
);
1934 for (i
= 0; i
< t
->num_targets
; i
++) {
1935 struct dm_target
*ti
= t
->targets
+ i
;
1937 if (!ti
->type
->preresume
)
1940 r
= ti
->type
->preresume(ti
);
1942 DMERR("%s: %s: preresume failed, error = %d",
1943 dm_device_name(t
->md
), ti
->type
->name
, r
);
1948 for (i
= 0; i
< t
->num_targets
; i
++) {
1949 struct dm_target
*ti
= t
->targets
+ i
;
1951 if (ti
->type
->resume
)
1952 ti
->type
->resume(ti
);
1958 void dm_table_add_target_callbacks(struct dm_table
*t
, struct dm_target_callbacks
*cb
)
1960 list_add(&cb
->list
, &t
->target_callbacks
);
1962 EXPORT_SYMBOL_GPL(dm_table_add_target_callbacks
);
1964 int dm_table_any_congested(struct dm_table
*t
, int bdi_bits
)
1966 struct dm_dev_internal
*dd
;
1967 struct list_head
*devices
= dm_table_get_devices(t
);
1968 struct dm_target_callbacks
*cb
;
1971 list_for_each_entry(dd
, devices
, list
) {
1972 struct request_queue
*q
= bdev_get_queue(dd
->dm_dev
->bdev
);
1973 char b
[BDEVNAME_SIZE
];
1976 r
|= bdi_congested(q
->backing_dev_info
, bdi_bits
);
1978 DMWARN_LIMIT("%s: any_congested: nonexistent device %s",
1979 dm_device_name(t
->md
),
1980 bdevname(dd
->dm_dev
->bdev
, b
));
1983 list_for_each_entry(cb
, &t
->target_callbacks
, list
)
1984 if (cb
->congested_fn
)
1985 r
|= cb
->congested_fn(cb
, bdi_bits
);
1990 struct mapped_device
*dm_table_get_md(struct dm_table
*t
)
1994 EXPORT_SYMBOL(dm_table_get_md
);
1996 void dm_table_run_md_queue_async(struct dm_table
*t
)
1998 struct mapped_device
*md
;
1999 struct request_queue
*queue
;
2000 unsigned long flags
;
2002 if (!dm_table_request_based(t
))
2005 md
= dm_table_get_md(t
);
2006 queue
= dm_get_md_queue(md
);
2009 blk_mq_run_hw_queues(queue
, true);
2011 spin_lock_irqsave(queue
->queue_lock
, flags
);
2012 blk_run_queue_async(queue
);
2013 spin_unlock_irqrestore(queue
->queue_lock
, flags
);
2017 EXPORT_SYMBOL(dm_table_run_md_queue_async
);