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Commit | Line | Data |
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7a87edfe JT |
1 | /* |
2 | * Copyright (C) 2012 Red Hat, Inc. | |
3 | * | |
4 | * This file is released under the GPL. | |
5 | */ | |
6 | ||
7 | #include "dm-bitset.h" | |
8 | #include "dm-transaction-manager.h" | |
9 | ||
10 | #include <linux/export.h> | |
11 | #include <linux/device-mapper.h> | |
12 | ||
13 | #define DM_MSG_PREFIX "bitset" | |
14 | #define BITS_PER_ARRAY_ENTRY 64 | |
15 | ||
16 | /*----------------------------------------------------------------*/ | |
17 | ||
18 | static struct dm_btree_value_type bitset_bvt = { | |
19 | .context = NULL, | |
20 | .size = sizeof(__le64), | |
21 | .inc = NULL, | |
22 | .dec = NULL, | |
23 | .equal = NULL, | |
24 | }; | |
25 | ||
26 | /*----------------------------------------------------------------*/ | |
27 | ||
28 | void dm_disk_bitset_init(struct dm_transaction_manager *tm, | |
29 | struct dm_disk_bitset *info) | |
30 | { | |
31 | dm_array_info_init(&info->array_info, tm, &bitset_bvt); | |
32 | info->current_index_set = false; | |
33 | } | |
34 | EXPORT_SYMBOL_GPL(dm_disk_bitset_init); | |
35 | ||
36 | int dm_bitset_empty(struct dm_disk_bitset *info, dm_block_t *root) | |
37 | { | |
38 | return dm_array_empty(&info->array_info, root); | |
39 | } | |
40 | EXPORT_SYMBOL_GPL(dm_bitset_empty); | |
41 | ||
42 | int dm_bitset_resize(struct dm_disk_bitset *info, dm_block_t root, | |
43 | uint32_t old_nr_entries, uint32_t new_nr_entries, | |
44 | bool default_value, dm_block_t *new_root) | |
45 | { | |
46 | uint32_t old_blocks = dm_div_up(old_nr_entries, BITS_PER_ARRAY_ENTRY); | |
47 | uint32_t new_blocks = dm_div_up(new_nr_entries, BITS_PER_ARRAY_ENTRY); | |
48 | __le64 value = default_value ? cpu_to_le64(~0) : cpu_to_le64(0); | |
49 | ||
50 | __dm_bless_for_disk(&value); | |
51 | return dm_array_resize(&info->array_info, root, old_blocks, new_blocks, | |
52 | &value, new_root); | |
53 | } | |
54 | EXPORT_SYMBOL_GPL(dm_bitset_resize); | |
55 | ||
56 | int dm_bitset_del(struct dm_disk_bitset *info, dm_block_t root) | |
57 | { | |
58 | return dm_array_del(&info->array_info, root); | |
59 | } | |
60 | EXPORT_SYMBOL_GPL(dm_bitset_del); | |
61 | ||
62 | int dm_bitset_flush(struct dm_disk_bitset *info, dm_block_t root, | |
63 | dm_block_t *new_root) | |
64 | { | |
65 | int r; | |
66 | __le64 value; | |
67 | ||
428e4698 | 68 | if (!info->current_index_set || !info->dirty) |
7a87edfe JT |
69 | return 0; |
70 | ||
71 | value = cpu_to_le64(info->current_bits); | |
72 | ||
73 | __dm_bless_for_disk(&value); | |
74 | r = dm_array_set_value(&info->array_info, root, info->current_index, | |
75 | &value, new_root); | |
76 | if (r) | |
77 | return r; | |
78 | ||
79 | info->current_index_set = false; | |
428e4698 JT |
80 | info->dirty = false; |
81 | ||
7a87edfe JT |
82 | return 0; |
83 | } | |
84 | EXPORT_SYMBOL_GPL(dm_bitset_flush); | |
85 | ||
86 | static int read_bits(struct dm_disk_bitset *info, dm_block_t root, | |
87 | uint32_t array_index) | |
88 | { | |
89 | int r; | |
90 | __le64 value; | |
91 | ||
92 | r = dm_array_get_value(&info->array_info, root, array_index, &value); | |
93 | if (r) | |
94 | return r; | |
95 | ||
96 | info->current_bits = le64_to_cpu(value); | |
97 | info->current_index_set = true; | |
98 | info->current_index = array_index; | |
428e4698 JT |
99 | info->dirty = false; |
100 | ||
7a87edfe JT |
101 | return 0; |
102 | } | |
103 | ||
104 | static int get_array_entry(struct dm_disk_bitset *info, dm_block_t root, | |
105 | uint32_t index, dm_block_t *new_root) | |
106 | { | |
107 | int r; | |
108 | unsigned array_index = index / BITS_PER_ARRAY_ENTRY; | |
109 | ||
110 | if (info->current_index_set) { | |
111 | if (info->current_index == array_index) | |
112 | return 0; | |
113 | ||
114 | r = dm_bitset_flush(info, root, new_root); | |
115 | if (r) | |
116 | return r; | |
117 | } | |
118 | ||
119 | return read_bits(info, root, array_index); | |
120 | } | |
121 | ||
122 | int dm_bitset_set_bit(struct dm_disk_bitset *info, dm_block_t root, | |
123 | uint32_t index, dm_block_t *new_root) | |
124 | { | |
125 | int r; | |
126 | unsigned b = index % BITS_PER_ARRAY_ENTRY; | |
127 | ||
128 | r = get_array_entry(info, root, index, new_root); | |
129 | if (r) | |
130 | return r; | |
131 | ||
132 | set_bit(b, (unsigned long *) &info->current_bits); | |
428e4698 JT |
133 | info->dirty = true; |
134 | ||
7a87edfe JT |
135 | return 0; |
136 | } | |
137 | EXPORT_SYMBOL_GPL(dm_bitset_set_bit); | |
138 | ||
139 | int dm_bitset_clear_bit(struct dm_disk_bitset *info, dm_block_t root, | |
140 | uint32_t index, dm_block_t *new_root) | |
141 | { | |
142 | int r; | |
143 | unsigned b = index % BITS_PER_ARRAY_ENTRY; | |
144 | ||
145 | r = get_array_entry(info, root, index, new_root); | |
146 | if (r) | |
147 | return r; | |
148 | ||
149 | clear_bit(b, (unsigned long *) &info->current_bits); | |
428e4698 JT |
150 | info->dirty = true; |
151 | ||
7a87edfe JT |
152 | return 0; |
153 | } | |
154 | EXPORT_SYMBOL_GPL(dm_bitset_clear_bit); | |
155 | ||
156 | int dm_bitset_test_bit(struct dm_disk_bitset *info, dm_block_t root, | |
157 | uint32_t index, dm_block_t *new_root, bool *result) | |
158 | { | |
159 | int r; | |
160 | unsigned b = index % BITS_PER_ARRAY_ENTRY; | |
161 | ||
162 | r = get_array_entry(info, root, index, new_root); | |
163 | if (r) | |
164 | return r; | |
165 | ||
166 | *result = test_bit(b, (unsigned long *) &info->current_bits); | |
167 | return 0; | |
168 | } | |
169 | EXPORT_SYMBOL_GPL(dm_bitset_test_bit); | |
170 | ||
171 | /*----------------------------------------------------------------*/ |