md/persistent-data/dm-bitset.h

1 /* SPDX-License-Identifier: GPL-2.0-only */
10 #include "dm-array.h"
12 /*----------------------------------------------------------------*/
19  * Like the dm-array that it's based on, the caller needs to keep track of
20  * the size of the bitset separately.  The underlying dm-array implicitly
21  * knows how many words it's storing and will return -ENODATA if you try
34  * b) Get yourself a root.  The root is the index of a block of data on the
36  *    pre existing root in your metadata that you wish to use, or you may
41  * root for a _new_ array.  If you've incremented the old root, via
43  * it in parallel with the new root.
46  * return a root for a new, updated bitset.
82  * tm - the transaction manager that should supervise this structure
83  * info - the structure being initialised
91  * info - describes the bitset
92  * new_root - on success, points to the new root block
102  * info - describes the array
103  * root - the root block of the array on disk
104  * size - the number of entries in the array
105  * fn - the callback
106  * context - passed to the callback
109 int dm_bitset_new(struct dm_disk_bitset *info, dm_block_t *root,
115  * info - describes the bitset
116  * old_root - the root block of the array on disk
117  * old_nr_entries - the number of bits in the old bitset
118  * new_nr_entries - the number of bits you want in the new bitset
119  * default_value - the value for any new bits
120  * new_root - on success, points to the new root block
129 int dm_bitset_del(struct dm_disk_bitset *info, dm_block_t root);
134  * info - describes the bitset
135  * root - the root block of the bitset
136  * index - the bit index
137  * new_root - on success, points to the new root block
139  * -ENODATA will be returned if the index is out of bounds.
141 int dm_bitset_set_bit(struct dm_disk_bitset *info, dm_block_t root,
147  * info - describes the bitset
148  * root - the root block of the bitset
149  * index - the bit index
150  * new_root - on success, points to the new root block
152  * -ENODATA will be returned if the index is out of bounds.
154 int dm_bitset_clear_bit(struct dm_disk_bitset *info, dm_block_t root,
160  * info - describes the bitset
161  * root - the root block of the bitset
162  * index - the bit index
163  * new_root - on success, points to the new root block (cached values may have been written)
164  * result - the bit value you're after
166  * -ENODATA will be returned if the index is out of bounds.
168 int dm_bitset_test_bit(struct dm_disk_bitset *info, dm_block_t root,
174  * info - describes the bitset
175  * root - the root block of the bitset
176  * new_root - on success, points to the new root block
178 int dm_bitset_flush(struct dm_disk_bitset *info, dm_block_t root,
192  * Make sure you've flush any dm_disk_bitset and updated the root before
196 			   dm_block_t root, uint32_t nr_entries,
204 /*----------------------------------------------------------------*/