root / block / qcow2-refcount.c @ 2dedf83e
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1 | f7d0fe02 | Kevin Wolf | /*
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2 | f7d0fe02 | Kevin Wolf | * Block driver for the QCOW version 2 format
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3 | f7d0fe02 | Kevin Wolf | *
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4 | f7d0fe02 | Kevin Wolf | * Copyright (c) 2004-2006 Fabrice Bellard
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5 | f7d0fe02 | Kevin Wolf | *
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6 | f7d0fe02 | Kevin Wolf | * Permission is hereby granted, free of charge, to any person obtaining a copy
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7 | f7d0fe02 | Kevin Wolf | * of this software and associated documentation files (the "Software"), to deal
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8 | f7d0fe02 | Kevin Wolf | * in the Software without restriction, including without limitation the rights
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9 | f7d0fe02 | Kevin Wolf | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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10 | f7d0fe02 | Kevin Wolf | * copies of the Software, and to permit persons to whom the Software is
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11 | f7d0fe02 | Kevin Wolf | * furnished to do so, subject to the following conditions:
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12 | f7d0fe02 | Kevin Wolf | *
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13 | f7d0fe02 | Kevin Wolf | * The above copyright notice and this permission notice shall be included in
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14 | f7d0fe02 | Kevin Wolf | * all copies or substantial portions of the Software.
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15 | f7d0fe02 | Kevin Wolf | *
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16 | f7d0fe02 | Kevin Wolf | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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17 | f7d0fe02 | Kevin Wolf | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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18 | f7d0fe02 | Kevin Wolf | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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19 | f7d0fe02 | Kevin Wolf | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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20 | f7d0fe02 | Kevin Wolf | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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21 | f7d0fe02 | Kevin Wolf | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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22 | f7d0fe02 | Kevin Wolf | * THE SOFTWARE.
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23 | f7d0fe02 | Kevin Wolf | */
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24 | f7d0fe02 | Kevin Wolf | |
25 | f7d0fe02 | Kevin Wolf | #include "qemu-common.h" |
26 | f7d0fe02 | Kevin Wolf | #include "block_int.h" |
27 | f7d0fe02 | Kevin Wolf | #include "block/qcow2.h" |
28 | f7d0fe02 | Kevin Wolf | |
29 | f7d0fe02 | Kevin Wolf | static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size);
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30 | f7d0fe02 | Kevin Wolf | static int update_refcount(BlockDriverState *bs, |
31 | f7d0fe02 | Kevin Wolf | int64_t offset, int64_t length, |
32 | f7d0fe02 | Kevin Wolf | int addend);
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33 | f7d0fe02 | Kevin Wolf | |
34 | 3b88e52b | Kevin Wolf | |
35 | 3b88e52b | Kevin Wolf | static int cache_refcount_updates = 0; |
36 | 3b88e52b | Kevin Wolf | |
37 | 3b88e52b | Kevin Wolf | static int write_refcount_block(BDRVQcowState *s) |
38 | 3b88e52b | Kevin Wolf | { |
39 | 3b88e52b | Kevin Wolf | size_t size = s->cluster_size; |
40 | 3b88e52b | Kevin Wolf | |
41 | 3b88e52b | Kevin Wolf | if (s->refcount_block_cache_offset == 0) { |
42 | 3b88e52b | Kevin Wolf | return 0; |
43 | 3b88e52b | Kevin Wolf | } |
44 | 3b88e52b | Kevin Wolf | |
45 | 3b88e52b | Kevin Wolf | if (bdrv_pwrite(s->hd, s->refcount_block_cache_offset,
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46 | 3b88e52b | Kevin Wolf | s->refcount_block_cache, size) != size) |
47 | 3b88e52b | Kevin Wolf | { |
48 | 3b88e52b | Kevin Wolf | return -EIO;
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49 | 3b88e52b | Kevin Wolf | } |
50 | 3b88e52b | Kevin Wolf | |
51 | 3b88e52b | Kevin Wolf | return 0; |
52 | 3b88e52b | Kevin Wolf | } |
53 | 3b88e52b | Kevin Wolf | |
54 | f7d0fe02 | Kevin Wolf | /*********************************************************/
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55 | f7d0fe02 | Kevin Wolf | /* refcount handling */
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56 | f7d0fe02 | Kevin Wolf | |
57 | ed6ccf0f | Kevin Wolf | int qcow2_refcount_init(BlockDriverState *bs)
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58 | f7d0fe02 | Kevin Wolf | { |
59 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
60 | f7d0fe02 | Kevin Wolf | int ret, refcount_table_size2, i;
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61 | f7d0fe02 | Kevin Wolf | |
62 | f7d0fe02 | Kevin Wolf | s->refcount_block_cache = qemu_malloc(s->cluster_size); |
63 | f7d0fe02 | Kevin Wolf | refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
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64 | f7d0fe02 | Kevin Wolf | s->refcount_table = qemu_malloc(refcount_table_size2); |
65 | f7d0fe02 | Kevin Wolf | if (s->refcount_table_size > 0) { |
66 | f7d0fe02 | Kevin Wolf | ret = bdrv_pread(s->hd, s->refcount_table_offset, |
67 | f7d0fe02 | Kevin Wolf | s->refcount_table, refcount_table_size2); |
68 | f7d0fe02 | Kevin Wolf | if (ret != refcount_table_size2)
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69 | f7d0fe02 | Kevin Wolf | goto fail;
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70 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->refcount_table_size; i++) |
71 | f7d0fe02 | Kevin Wolf | be64_to_cpus(&s->refcount_table[i]); |
72 | f7d0fe02 | Kevin Wolf | } |
73 | f7d0fe02 | Kevin Wolf | return 0; |
74 | f7d0fe02 | Kevin Wolf | fail:
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75 | f7d0fe02 | Kevin Wolf | return -ENOMEM;
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76 | f7d0fe02 | Kevin Wolf | } |
77 | f7d0fe02 | Kevin Wolf | |
78 | ed6ccf0f | Kevin Wolf | void qcow2_refcount_close(BlockDriverState *bs)
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79 | f7d0fe02 | Kevin Wolf | { |
80 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
81 | f7d0fe02 | Kevin Wolf | qemu_free(s->refcount_block_cache); |
82 | f7d0fe02 | Kevin Wolf | qemu_free(s->refcount_table); |
83 | f7d0fe02 | Kevin Wolf | } |
84 | f7d0fe02 | Kevin Wolf | |
85 | f7d0fe02 | Kevin Wolf | |
86 | f7d0fe02 | Kevin Wolf | static int load_refcount_block(BlockDriverState *bs, |
87 | f7d0fe02 | Kevin Wolf | int64_t refcount_block_offset) |
88 | f7d0fe02 | Kevin Wolf | { |
89 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
90 | f7d0fe02 | Kevin Wolf | int ret;
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91 | 3b88e52b | Kevin Wolf | |
92 | 3b88e52b | Kevin Wolf | if (cache_refcount_updates) {
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93 | 3b88e52b | Kevin Wolf | write_refcount_block(s); |
94 | 3b88e52b | Kevin Wolf | } |
95 | 3b88e52b | Kevin Wolf | |
96 | f7d0fe02 | Kevin Wolf | ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache, |
97 | f7d0fe02 | Kevin Wolf | s->cluster_size); |
98 | f7d0fe02 | Kevin Wolf | if (ret != s->cluster_size)
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99 | f7d0fe02 | Kevin Wolf | return -EIO;
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100 | f7d0fe02 | Kevin Wolf | s->refcount_block_cache_offset = refcount_block_offset; |
101 | f7d0fe02 | Kevin Wolf | return 0; |
102 | f7d0fe02 | Kevin Wolf | } |
103 | f7d0fe02 | Kevin Wolf | |
104 | f7d0fe02 | Kevin Wolf | static int get_refcount(BlockDriverState *bs, int64_t cluster_index) |
105 | f7d0fe02 | Kevin Wolf | { |
106 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
107 | f7d0fe02 | Kevin Wolf | int refcount_table_index, block_index;
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108 | f7d0fe02 | Kevin Wolf | int64_t refcount_block_offset; |
109 | f7d0fe02 | Kevin Wolf | |
110 | f7d0fe02 | Kevin Wolf | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
111 | f7d0fe02 | Kevin Wolf | if (refcount_table_index >= s->refcount_table_size)
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112 | f7d0fe02 | Kevin Wolf | return 0; |
113 | f7d0fe02 | Kevin Wolf | refcount_block_offset = s->refcount_table[refcount_table_index]; |
114 | f7d0fe02 | Kevin Wolf | if (!refcount_block_offset)
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115 | f7d0fe02 | Kevin Wolf | return 0; |
116 | f7d0fe02 | Kevin Wolf | if (refcount_block_offset != s->refcount_block_cache_offset) {
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117 | f7d0fe02 | Kevin Wolf | /* better than nothing: return allocated if read error */
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118 | f7d0fe02 | Kevin Wolf | if (load_refcount_block(bs, refcount_block_offset) < 0) |
119 | f7d0fe02 | Kevin Wolf | return 1; |
120 | f7d0fe02 | Kevin Wolf | } |
121 | f7d0fe02 | Kevin Wolf | block_index = cluster_index & |
122 | f7d0fe02 | Kevin Wolf | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
123 | f7d0fe02 | Kevin Wolf | return be16_to_cpu(s->refcount_block_cache[block_index]);
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124 | f7d0fe02 | Kevin Wolf | } |
125 | f7d0fe02 | Kevin Wolf | |
126 | f7d0fe02 | Kevin Wolf | static int grow_refcount_table(BlockDriverState *bs, int min_size) |
127 | f7d0fe02 | Kevin Wolf | { |
128 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
129 | f7d0fe02 | Kevin Wolf | int new_table_size, new_table_size2, refcount_table_clusters, i, ret;
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130 | f7d0fe02 | Kevin Wolf | uint64_t *new_table; |
131 | f7d0fe02 | Kevin Wolf | int64_t table_offset; |
132 | f7d0fe02 | Kevin Wolf | uint8_t data[12];
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133 | f7d0fe02 | Kevin Wolf | int old_table_size;
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134 | f7d0fe02 | Kevin Wolf | int64_t old_table_offset; |
135 | f7d0fe02 | Kevin Wolf | |
136 | f7d0fe02 | Kevin Wolf | if (min_size <= s->refcount_table_size)
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137 | f7d0fe02 | Kevin Wolf | return 0; |
138 | f7d0fe02 | Kevin Wolf | /* compute new table size */
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139 | f7d0fe02 | Kevin Wolf | refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3);
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140 | f7d0fe02 | Kevin Wolf | for(;;) {
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141 | f7d0fe02 | Kevin Wolf | if (refcount_table_clusters == 0) { |
142 | f7d0fe02 | Kevin Wolf | refcount_table_clusters = 1;
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143 | f7d0fe02 | Kevin Wolf | } else {
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144 | f7d0fe02 | Kevin Wolf | refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2; |
145 | f7d0fe02 | Kevin Wolf | } |
146 | f7d0fe02 | Kevin Wolf | new_table_size = refcount_table_clusters << (s->cluster_bits - 3);
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147 | f7d0fe02 | Kevin Wolf | if (min_size <= new_table_size)
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148 | f7d0fe02 | Kevin Wolf | break;
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149 | f7d0fe02 | Kevin Wolf | } |
150 | f7d0fe02 | Kevin Wolf | #ifdef DEBUG_ALLOC2
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151 | f7d0fe02 | Kevin Wolf | printf("grow_refcount_table from %d to %d\n",
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152 | f7d0fe02 | Kevin Wolf | s->refcount_table_size, |
153 | f7d0fe02 | Kevin Wolf | new_table_size); |
154 | f7d0fe02 | Kevin Wolf | #endif
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155 | f7d0fe02 | Kevin Wolf | new_table_size2 = new_table_size * sizeof(uint64_t);
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156 | f7d0fe02 | Kevin Wolf | new_table = qemu_mallocz(new_table_size2); |
157 | f7d0fe02 | Kevin Wolf | memcpy(new_table, s->refcount_table, |
158 | f7d0fe02 | Kevin Wolf | s->refcount_table_size * sizeof(uint64_t));
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159 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->refcount_table_size; i++) |
160 | f7d0fe02 | Kevin Wolf | cpu_to_be64s(&new_table[i]); |
161 | f7d0fe02 | Kevin Wolf | /* Note: we cannot update the refcount now to avoid recursion */
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162 | f7d0fe02 | Kevin Wolf | table_offset = alloc_clusters_noref(bs, new_table_size2); |
163 | f7d0fe02 | Kevin Wolf | ret = bdrv_pwrite(s->hd, table_offset, new_table, new_table_size2); |
164 | f7d0fe02 | Kevin Wolf | if (ret != new_table_size2)
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165 | f7d0fe02 | Kevin Wolf | goto fail;
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166 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->refcount_table_size; i++) |
167 | f7d0fe02 | Kevin Wolf | be64_to_cpus(&new_table[i]); |
168 | f7d0fe02 | Kevin Wolf | |
169 | f7d0fe02 | Kevin Wolf | cpu_to_be64w((uint64_t*)data, table_offset); |
170 | f7d0fe02 | Kevin Wolf | cpu_to_be32w((uint32_t*)(data + 8), refcount_table_clusters);
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171 | f2b7c8b3 | Kevin Wolf | ret = bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset), |
172 | f2b7c8b3 | Kevin Wolf | data, sizeof(data));
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173 | f2b7c8b3 | Kevin Wolf | if (ret != sizeof(data)) { |
174 | f7d0fe02 | Kevin Wolf | goto fail;
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175 | f2b7c8b3 | Kevin Wolf | } |
176 | f2b7c8b3 | Kevin Wolf | |
177 | f7d0fe02 | Kevin Wolf | qemu_free(s->refcount_table); |
178 | f7d0fe02 | Kevin Wolf | old_table_offset = s->refcount_table_offset; |
179 | f7d0fe02 | Kevin Wolf | old_table_size = s->refcount_table_size; |
180 | f7d0fe02 | Kevin Wolf | s->refcount_table = new_table; |
181 | f7d0fe02 | Kevin Wolf | s->refcount_table_size = new_table_size; |
182 | f7d0fe02 | Kevin Wolf | s->refcount_table_offset = table_offset; |
183 | f7d0fe02 | Kevin Wolf | |
184 | f7d0fe02 | Kevin Wolf | update_refcount(bs, table_offset, new_table_size2, 1);
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185 | ed6ccf0f | Kevin Wolf | qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
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186 | f7d0fe02 | Kevin Wolf | return 0; |
187 | f7d0fe02 | Kevin Wolf | fail:
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188 | f7d0fe02 | Kevin Wolf | qemu_free(new_table); |
189 | f2b7c8b3 | Kevin Wolf | return ret < 0 ? ret : -EIO; |
190 | f7d0fe02 | Kevin Wolf | } |
191 | f7d0fe02 | Kevin Wolf | |
192 | f7d0fe02 | Kevin Wolf | |
193 | f7d0fe02 | Kevin Wolf | static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
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194 | f7d0fe02 | Kevin Wolf | { |
195 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
196 | f7d0fe02 | Kevin Wolf | int64_t offset, refcount_block_offset; |
197 | 80ee15a6 | Kevin Wolf | unsigned int refcount_table_index; |
198 | 80ee15a6 | Kevin Wolf | int ret;
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199 | f7d0fe02 | Kevin Wolf | uint64_t data64; |
200 | 3b88e52b | Kevin Wolf | int cache = cache_refcount_updates;
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201 | f7d0fe02 | Kevin Wolf | |
202 | f7d0fe02 | Kevin Wolf | /* Find L1 index and grow refcount table if needed */
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203 | f7d0fe02 | Kevin Wolf | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
204 | f7d0fe02 | Kevin Wolf | if (refcount_table_index >= s->refcount_table_size) {
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205 | f7d0fe02 | Kevin Wolf | ret = grow_refcount_table(bs, refcount_table_index + 1);
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206 | f7d0fe02 | Kevin Wolf | if (ret < 0) |
207 | f7d0fe02 | Kevin Wolf | return ret;
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208 | f7d0fe02 | Kevin Wolf | } |
209 | f7d0fe02 | Kevin Wolf | |
210 | f7d0fe02 | Kevin Wolf | /* Load or allocate the refcount block */
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211 | f7d0fe02 | Kevin Wolf | refcount_block_offset = s->refcount_table[refcount_table_index]; |
212 | f7d0fe02 | Kevin Wolf | if (!refcount_block_offset) {
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213 | 3b88e52b | Kevin Wolf | if (cache_refcount_updates) {
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214 | 3b88e52b | Kevin Wolf | write_refcount_block(s); |
215 | 3b88e52b | Kevin Wolf | cache_refcount_updates = 0;
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216 | 3b88e52b | Kevin Wolf | } |
217 | f7d0fe02 | Kevin Wolf | /* create a new refcount block */
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218 | f7d0fe02 | Kevin Wolf | /* Note: we cannot update the refcount now to avoid recursion */
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219 | f7d0fe02 | Kevin Wolf | offset = alloc_clusters_noref(bs, s->cluster_size); |
220 | f7d0fe02 | Kevin Wolf | memset(s->refcount_block_cache, 0, s->cluster_size);
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221 | f7d0fe02 | Kevin Wolf | ret = bdrv_pwrite(s->hd, offset, s->refcount_block_cache, s->cluster_size); |
222 | f7d0fe02 | Kevin Wolf | if (ret != s->cluster_size)
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223 | f7d0fe02 | Kevin Wolf | return -EINVAL;
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224 | f7d0fe02 | Kevin Wolf | s->refcount_table[refcount_table_index] = offset; |
225 | f7d0fe02 | Kevin Wolf | data64 = cpu_to_be64(offset); |
226 | f7d0fe02 | Kevin Wolf | ret = bdrv_pwrite(s->hd, s->refcount_table_offset + |
227 | f7d0fe02 | Kevin Wolf | refcount_table_index * sizeof(uint64_t),
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228 | f7d0fe02 | Kevin Wolf | &data64, sizeof(data64));
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229 | f7d0fe02 | Kevin Wolf | if (ret != sizeof(data64)) |
230 | f7d0fe02 | Kevin Wolf | return -EINVAL;
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231 | f7d0fe02 | Kevin Wolf | |
232 | f7d0fe02 | Kevin Wolf | refcount_block_offset = offset; |
233 | f7d0fe02 | Kevin Wolf | s->refcount_block_cache_offset = offset; |
234 | f7d0fe02 | Kevin Wolf | update_refcount(bs, offset, s->cluster_size, 1);
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235 | 3b88e52b | Kevin Wolf | cache_refcount_updates = cache; |
236 | f7d0fe02 | Kevin Wolf | } else {
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237 | f7d0fe02 | Kevin Wolf | if (refcount_block_offset != s->refcount_block_cache_offset) {
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238 | f7d0fe02 | Kevin Wolf | if (load_refcount_block(bs, refcount_block_offset) < 0) |
239 | f7d0fe02 | Kevin Wolf | return -EIO;
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240 | f7d0fe02 | Kevin Wolf | } |
241 | f7d0fe02 | Kevin Wolf | } |
242 | f7d0fe02 | Kevin Wolf | |
243 | f7d0fe02 | Kevin Wolf | return refcount_block_offset;
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244 | f7d0fe02 | Kevin Wolf | } |
245 | f7d0fe02 | Kevin Wolf | |
246 | 9923e05e | Kevin Wolf | #define REFCOUNTS_PER_SECTOR (512 >> REFCOUNT_SHIFT) |
247 | 9923e05e | Kevin Wolf | static int write_refcount_block_entries(BDRVQcowState *s, |
248 | 9923e05e | Kevin Wolf | int64_t refcount_block_offset, int first_index, int last_index) |
249 | 9923e05e | Kevin Wolf | { |
250 | 9923e05e | Kevin Wolf | size_t size; |
251 | 9923e05e | Kevin Wolf | |
252 | 3b88e52b | Kevin Wolf | if (cache_refcount_updates) {
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253 | 3b88e52b | Kevin Wolf | return 0; |
254 | 3b88e52b | Kevin Wolf | } |
255 | 3b88e52b | Kevin Wolf | |
256 | 9923e05e | Kevin Wolf | first_index &= ~(REFCOUNTS_PER_SECTOR - 1);
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257 | 9923e05e | Kevin Wolf | last_index = (last_index + REFCOUNTS_PER_SECTOR) |
258 | 9923e05e | Kevin Wolf | & ~(REFCOUNTS_PER_SECTOR - 1);
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259 | 9923e05e | Kevin Wolf | |
260 | 9923e05e | Kevin Wolf | size = (last_index - first_index) << REFCOUNT_SHIFT; |
261 | 9923e05e | Kevin Wolf | if (bdrv_pwrite(s->hd,
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262 | 9923e05e | Kevin Wolf | refcount_block_offset + (first_index << REFCOUNT_SHIFT), |
263 | 9923e05e | Kevin Wolf | &s->refcount_block_cache[first_index], size) != size) |
264 | 9923e05e | Kevin Wolf | { |
265 | 9923e05e | Kevin Wolf | return -EIO;
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266 | 9923e05e | Kevin Wolf | } |
267 | 9923e05e | Kevin Wolf | |
268 | 9923e05e | Kevin Wolf | return 0; |
269 | 9923e05e | Kevin Wolf | } |
270 | 9923e05e | Kevin Wolf | |
271 | f7d0fe02 | Kevin Wolf | /* XXX: cache several refcount block clusters ? */
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272 | db3a964f | Kevin Wolf | static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, |
273 | db3a964f | Kevin Wolf | int64_t offset, int64_t length, int addend)
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274 | f7d0fe02 | Kevin Wolf | { |
275 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
276 | f7d0fe02 | Kevin Wolf | int64_t start, last, cluster_offset; |
277 | f7d0fe02 | Kevin Wolf | int64_t refcount_block_offset = 0;
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278 | f7d0fe02 | Kevin Wolf | int64_t table_index = -1, old_table_index;
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279 | f7d0fe02 | Kevin Wolf | int first_index = -1, last_index = -1; |
280 | 09508d13 | Kevin Wolf | int ret;
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281 | f7d0fe02 | Kevin Wolf | |
282 | f7d0fe02 | Kevin Wolf | #ifdef DEBUG_ALLOC2
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283 | 0bf9e31a | Blue Swirl | printf("update_refcount: offset=%" PRId64 " size=%" PRId64 " addend=%d\n", |
284 | f7d0fe02 | Kevin Wolf | offset, length, addend); |
285 | f7d0fe02 | Kevin Wolf | #endif
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286 | 7322afe7 | Kevin Wolf | if (length < 0) { |
287 | f7d0fe02 | Kevin Wolf | return -EINVAL;
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288 | 7322afe7 | Kevin Wolf | } else if (length == 0) { |
289 | 7322afe7 | Kevin Wolf | return 0; |
290 | 7322afe7 | Kevin Wolf | } |
291 | 7322afe7 | Kevin Wolf | |
292 | f7d0fe02 | Kevin Wolf | start = offset & ~(s->cluster_size - 1);
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293 | f7d0fe02 | Kevin Wolf | last = (offset + length - 1) & ~(s->cluster_size - 1); |
294 | f7d0fe02 | Kevin Wolf | for(cluster_offset = start; cluster_offset <= last;
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295 | f7d0fe02 | Kevin Wolf | cluster_offset += s->cluster_size) |
296 | f7d0fe02 | Kevin Wolf | { |
297 | f7d0fe02 | Kevin Wolf | int block_index, refcount;
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298 | f7d0fe02 | Kevin Wolf | int64_t cluster_index = cluster_offset >> s->cluster_bits; |
299 | 09508d13 | Kevin Wolf | int64_t new_block; |
300 | f7d0fe02 | Kevin Wolf | |
301 | f7d0fe02 | Kevin Wolf | /* Only write refcount block to disk when we are done with it */
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302 | f7d0fe02 | Kevin Wolf | old_table_index = table_index; |
303 | f7d0fe02 | Kevin Wolf | table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
304 | f7d0fe02 | Kevin Wolf | if ((old_table_index >= 0) && (table_index != old_table_index)) { |
305 | 9923e05e | Kevin Wolf | |
306 | 9923e05e | Kevin Wolf | if (write_refcount_block_entries(s, refcount_block_offset,
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307 | 9923e05e | Kevin Wolf | first_index, last_index) < 0)
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308 | f7d0fe02 | Kevin Wolf | { |
309 | f7d0fe02 | Kevin Wolf | return -EIO;
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310 | f7d0fe02 | Kevin Wolf | } |
311 | f7d0fe02 | Kevin Wolf | |
312 | f7d0fe02 | Kevin Wolf | first_index = -1;
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313 | f7d0fe02 | Kevin Wolf | last_index = -1;
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314 | f7d0fe02 | Kevin Wolf | } |
315 | f7d0fe02 | Kevin Wolf | |
316 | f7d0fe02 | Kevin Wolf | /* Load the refcount block and allocate it if needed */
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317 | 09508d13 | Kevin Wolf | new_block = alloc_refcount_block(bs, cluster_index); |
318 | 09508d13 | Kevin Wolf | if (new_block < 0) { |
319 | 09508d13 | Kevin Wolf | ret = new_block; |
320 | 09508d13 | Kevin Wolf | goto fail;
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321 | f7d0fe02 | Kevin Wolf | } |
322 | 09508d13 | Kevin Wolf | refcount_block_offset = new_block; |
323 | f7d0fe02 | Kevin Wolf | |
324 | f7d0fe02 | Kevin Wolf | /* we can update the count and save it */
|
325 | f7d0fe02 | Kevin Wolf | block_index = cluster_index & |
326 | f7d0fe02 | Kevin Wolf | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
327 | f7d0fe02 | Kevin Wolf | if (first_index == -1 || block_index < first_index) { |
328 | f7d0fe02 | Kevin Wolf | first_index = block_index; |
329 | f7d0fe02 | Kevin Wolf | } |
330 | f7d0fe02 | Kevin Wolf | if (block_index > last_index) {
|
331 | f7d0fe02 | Kevin Wolf | last_index = block_index; |
332 | f7d0fe02 | Kevin Wolf | } |
333 | f7d0fe02 | Kevin Wolf | |
334 | f7d0fe02 | Kevin Wolf | refcount = be16_to_cpu(s->refcount_block_cache[block_index]); |
335 | f7d0fe02 | Kevin Wolf | refcount += addend; |
336 | 09508d13 | Kevin Wolf | if (refcount < 0 || refcount > 0xffff) { |
337 | 09508d13 | Kevin Wolf | ret = -EINVAL; |
338 | 09508d13 | Kevin Wolf | goto fail;
|
339 | 09508d13 | Kevin Wolf | } |
340 | f7d0fe02 | Kevin Wolf | if (refcount == 0 && cluster_index < s->free_cluster_index) { |
341 | f7d0fe02 | Kevin Wolf | s->free_cluster_index = cluster_index; |
342 | f7d0fe02 | Kevin Wolf | } |
343 | f7d0fe02 | Kevin Wolf | s->refcount_block_cache[block_index] = cpu_to_be16(refcount); |
344 | f7d0fe02 | Kevin Wolf | } |
345 | f7d0fe02 | Kevin Wolf | |
346 | 09508d13 | Kevin Wolf | ret = 0;
|
347 | 09508d13 | Kevin Wolf | fail:
|
348 | 09508d13 | Kevin Wolf | |
349 | f7d0fe02 | Kevin Wolf | /* Write last changed block to disk */
|
350 | f7d0fe02 | Kevin Wolf | if (refcount_block_offset != 0) { |
351 | 9923e05e | Kevin Wolf | if (write_refcount_block_entries(s, refcount_block_offset,
|
352 | 9923e05e | Kevin Wolf | first_index, last_index) < 0)
|
353 | f7d0fe02 | Kevin Wolf | { |
354 | 09508d13 | Kevin Wolf | return ret < 0 ? ret : -EIO; |
355 | f7d0fe02 | Kevin Wolf | } |
356 | f7d0fe02 | Kevin Wolf | } |
357 | f7d0fe02 | Kevin Wolf | |
358 | 09508d13 | Kevin Wolf | /*
|
359 | 09508d13 | Kevin Wolf | * Try do undo any updates if an error is returned (This may succeed in
|
360 | 09508d13 | Kevin Wolf | * some cases like ENOSPC for allocating a new refcount block)
|
361 | 09508d13 | Kevin Wolf | */
|
362 | 09508d13 | Kevin Wolf | if (ret < 0) { |
363 | 09508d13 | Kevin Wolf | int dummy;
|
364 | 09508d13 | Kevin Wolf | dummy = update_refcount(bs, offset, cluster_offset - offset, -addend); |
365 | 09508d13 | Kevin Wolf | } |
366 | 09508d13 | Kevin Wolf | |
367 | 09508d13 | Kevin Wolf | return ret;
|
368 | f7d0fe02 | Kevin Wolf | } |
369 | f7d0fe02 | Kevin Wolf | |
370 | f7d0fe02 | Kevin Wolf | /* addend must be 1 or -1 */
|
371 | f7d0fe02 | Kevin Wolf | static int update_cluster_refcount(BlockDriverState *bs, |
372 | f7d0fe02 | Kevin Wolf | int64_t cluster_index, |
373 | f7d0fe02 | Kevin Wolf | int addend)
|
374 | f7d0fe02 | Kevin Wolf | { |
375 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
376 | f7d0fe02 | Kevin Wolf | int ret;
|
377 | f7d0fe02 | Kevin Wolf | |
378 | f7d0fe02 | Kevin Wolf | ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend);
|
379 | f7d0fe02 | Kevin Wolf | if (ret < 0) { |
380 | f7d0fe02 | Kevin Wolf | return ret;
|
381 | f7d0fe02 | Kevin Wolf | } |
382 | f7d0fe02 | Kevin Wolf | |
383 | f7d0fe02 | Kevin Wolf | return get_refcount(bs, cluster_index);
|
384 | f7d0fe02 | Kevin Wolf | } |
385 | f7d0fe02 | Kevin Wolf | |
386 | f7d0fe02 | Kevin Wolf | |
387 | f7d0fe02 | Kevin Wolf | |
388 | f7d0fe02 | Kevin Wolf | /*********************************************************/
|
389 | f7d0fe02 | Kevin Wolf | /* cluster allocation functions */
|
390 | f7d0fe02 | Kevin Wolf | |
391 | f7d0fe02 | Kevin Wolf | |
392 | f7d0fe02 | Kevin Wolf | |
393 | f7d0fe02 | Kevin Wolf | /* return < 0 if error */
|
394 | f7d0fe02 | Kevin Wolf | static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
|
395 | f7d0fe02 | Kevin Wolf | { |
396 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
397 | f7d0fe02 | Kevin Wolf | int i, nb_clusters;
|
398 | f7d0fe02 | Kevin Wolf | |
399 | f7d0fe02 | Kevin Wolf | nb_clusters = size_to_clusters(s, size); |
400 | f7d0fe02 | Kevin Wolf | retry:
|
401 | f7d0fe02 | Kevin Wolf | for(i = 0; i < nb_clusters; i++) { |
402 | f7d0fe02 | Kevin Wolf | int64_t i = s->free_cluster_index++; |
403 | f7d0fe02 | Kevin Wolf | if (get_refcount(bs, i) != 0) |
404 | f7d0fe02 | Kevin Wolf | goto retry;
|
405 | f7d0fe02 | Kevin Wolf | } |
406 | f7d0fe02 | Kevin Wolf | #ifdef DEBUG_ALLOC2
|
407 | 0bf9e31a | Blue Swirl | printf("alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n", |
408 | f7d0fe02 | Kevin Wolf | size, |
409 | f7d0fe02 | Kevin Wolf | (s->free_cluster_index - nb_clusters) << s->cluster_bits); |
410 | f7d0fe02 | Kevin Wolf | #endif
|
411 | f7d0fe02 | Kevin Wolf | return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
|
412 | f7d0fe02 | Kevin Wolf | } |
413 | f7d0fe02 | Kevin Wolf | |
414 | ed6ccf0f | Kevin Wolf | int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size) |
415 | f7d0fe02 | Kevin Wolf | { |
416 | f7d0fe02 | Kevin Wolf | int64_t offset; |
417 | db3a964f | Kevin Wolf | int ret;
|
418 | f7d0fe02 | Kevin Wolf | |
419 | f7d0fe02 | Kevin Wolf | offset = alloc_clusters_noref(bs, size); |
420 | db3a964f | Kevin Wolf | ret = update_refcount(bs, offset, size, 1);
|
421 | db3a964f | Kevin Wolf | if (ret < 0) { |
422 | db3a964f | Kevin Wolf | return ret;
|
423 | db3a964f | Kevin Wolf | } |
424 | f7d0fe02 | Kevin Wolf | return offset;
|
425 | f7d0fe02 | Kevin Wolf | } |
426 | f7d0fe02 | Kevin Wolf | |
427 | f7d0fe02 | Kevin Wolf | /* only used to allocate compressed sectors. We try to allocate
|
428 | f7d0fe02 | Kevin Wolf | contiguous sectors. size must be <= cluster_size */
|
429 | ed6ccf0f | Kevin Wolf | int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
|
430 | f7d0fe02 | Kevin Wolf | { |
431 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
432 | f7d0fe02 | Kevin Wolf | int64_t offset, cluster_offset; |
433 | f7d0fe02 | Kevin Wolf | int free_in_cluster;
|
434 | f7d0fe02 | Kevin Wolf | |
435 | f7d0fe02 | Kevin Wolf | assert(size > 0 && size <= s->cluster_size);
|
436 | f7d0fe02 | Kevin Wolf | if (s->free_byte_offset == 0) { |
437 | ed6ccf0f | Kevin Wolf | s->free_byte_offset = qcow2_alloc_clusters(bs, s->cluster_size); |
438 | 5d757b56 | Kevin Wolf | if (s->free_byte_offset < 0) { |
439 | 5d757b56 | Kevin Wolf | return s->free_byte_offset;
|
440 | 5d757b56 | Kevin Wolf | } |
441 | f7d0fe02 | Kevin Wolf | } |
442 | f7d0fe02 | Kevin Wolf | redo:
|
443 | f7d0fe02 | Kevin Wolf | free_in_cluster = s->cluster_size - |
444 | f7d0fe02 | Kevin Wolf | (s->free_byte_offset & (s->cluster_size - 1));
|
445 | f7d0fe02 | Kevin Wolf | if (size <= free_in_cluster) {
|
446 | f7d0fe02 | Kevin Wolf | /* enough space in current cluster */
|
447 | f7d0fe02 | Kevin Wolf | offset = s->free_byte_offset; |
448 | f7d0fe02 | Kevin Wolf | s->free_byte_offset += size; |
449 | f7d0fe02 | Kevin Wolf | free_in_cluster -= size; |
450 | f7d0fe02 | Kevin Wolf | if (free_in_cluster == 0) |
451 | f7d0fe02 | Kevin Wolf | s->free_byte_offset = 0;
|
452 | f7d0fe02 | Kevin Wolf | if ((offset & (s->cluster_size - 1)) != 0) |
453 | f7d0fe02 | Kevin Wolf | update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
454 | f7d0fe02 | Kevin Wolf | } else {
|
455 | ed6ccf0f | Kevin Wolf | offset = qcow2_alloc_clusters(bs, s->cluster_size); |
456 | 5d757b56 | Kevin Wolf | if (offset < 0) { |
457 | 5d757b56 | Kevin Wolf | return offset;
|
458 | 5d757b56 | Kevin Wolf | } |
459 | f7d0fe02 | Kevin Wolf | cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
|
460 | f7d0fe02 | Kevin Wolf | if ((cluster_offset + s->cluster_size) == offset) {
|
461 | f7d0fe02 | Kevin Wolf | /* we are lucky: contiguous data */
|
462 | f7d0fe02 | Kevin Wolf | offset = s->free_byte_offset; |
463 | f7d0fe02 | Kevin Wolf | update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
464 | f7d0fe02 | Kevin Wolf | s->free_byte_offset += size; |
465 | f7d0fe02 | Kevin Wolf | } else {
|
466 | f7d0fe02 | Kevin Wolf | s->free_byte_offset = offset; |
467 | f7d0fe02 | Kevin Wolf | goto redo;
|
468 | f7d0fe02 | Kevin Wolf | } |
469 | f7d0fe02 | Kevin Wolf | } |
470 | f7d0fe02 | Kevin Wolf | return offset;
|
471 | f7d0fe02 | Kevin Wolf | } |
472 | f7d0fe02 | Kevin Wolf | |
473 | ed6ccf0f | Kevin Wolf | void qcow2_free_clusters(BlockDriverState *bs,
|
474 | f7d0fe02 | Kevin Wolf | int64_t offset, int64_t size) |
475 | f7d0fe02 | Kevin Wolf | { |
476 | db3a964f | Kevin Wolf | int ret;
|
477 | db3a964f | Kevin Wolf | |
478 | db3a964f | Kevin Wolf | ret = update_refcount(bs, offset, size, -1);
|
479 | db3a964f | Kevin Wolf | if (ret < 0) { |
480 | db3a964f | Kevin Wolf | fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
|
481 | db3a964f | Kevin Wolf | abort(); |
482 | db3a964f | Kevin Wolf | } |
483 | f7d0fe02 | Kevin Wolf | } |
484 | f7d0fe02 | Kevin Wolf | |
485 | 45aba42f | Kevin Wolf | /*
|
486 | 45aba42f | Kevin Wolf | * free_any_clusters
|
487 | 45aba42f | Kevin Wolf | *
|
488 | 45aba42f | Kevin Wolf | * free clusters according to its type: compressed or not
|
489 | 45aba42f | Kevin Wolf | *
|
490 | 45aba42f | Kevin Wolf | */
|
491 | 45aba42f | Kevin Wolf | |
492 | ed6ccf0f | Kevin Wolf | void qcow2_free_any_clusters(BlockDriverState *bs,
|
493 | 45aba42f | Kevin Wolf | uint64_t cluster_offset, int nb_clusters)
|
494 | 45aba42f | Kevin Wolf | { |
495 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
496 | 45aba42f | Kevin Wolf | |
497 | 45aba42f | Kevin Wolf | /* free the cluster */
|
498 | 45aba42f | Kevin Wolf | |
499 | 45aba42f | Kevin Wolf | if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
|
500 | 45aba42f | Kevin Wolf | int nb_csectors;
|
501 | 45aba42f | Kevin Wolf | nb_csectors = ((cluster_offset >> s->csize_shift) & |
502 | 45aba42f | Kevin Wolf | s->csize_mask) + 1;
|
503 | ed6ccf0f | Kevin Wolf | qcow2_free_clusters(bs, |
504 | ed6ccf0f | Kevin Wolf | (cluster_offset & s->cluster_offset_mask) & ~511,
|
505 | ed6ccf0f | Kevin Wolf | nb_csectors * 512);
|
506 | 45aba42f | Kevin Wolf | return;
|
507 | 45aba42f | Kevin Wolf | } |
508 | 45aba42f | Kevin Wolf | |
509 | ed6ccf0f | Kevin Wolf | qcow2_free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits); |
510 | 45aba42f | Kevin Wolf | |
511 | 45aba42f | Kevin Wolf | return;
|
512 | 45aba42f | Kevin Wolf | } |
513 | 45aba42f | Kevin Wolf | |
514 | f7d0fe02 | Kevin Wolf | |
515 | f7d0fe02 | Kevin Wolf | |
516 | f7d0fe02 | Kevin Wolf | /*********************************************************/
|
517 | f7d0fe02 | Kevin Wolf | /* snapshots and image creation */
|
518 | f7d0fe02 | Kevin Wolf | |
519 | f7d0fe02 | Kevin Wolf | |
520 | f7d0fe02 | Kevin Wolf | |
521 | ed6ccf0f | Kevin Wolf | void qcow2_create_refcount_update(QCowCreateState *s, int64_t offset,
|
522 | ed6ccf0f | Kevin Wolf | int64_t size) |
523 | f7d0fe02 | Kevin Wolf | { |
524 | f7d0fe02 | Kevin Wolf | int refcount;
|
525 | f7d0fe02 | Kevin Wolf | int64_t start, last, cluster_offset; |
526 | f7d0fe02 | Kevin Wolf | uint16_t *p; |
527 | f7d0fe02 | Kevin Wolf | |
528 | f7d0fe02 | Kevin Wolf | start = offset & ~(s->cluster_size - 1);
|
529 | f7d0fe02 | Kevin Wolf | last = (offset + size - 1) & ~(s->cluster_size - 1); |
530 | f7d0fe02 | Kevin Wolf | for(cluster_offset = start; cluster_offset <= last;
|
531 | f7d0fe02 | Kevin Wolf | cluster_offset += s->cluster_size) { |
532 | f7d0fe02 | Kevin Wolf | p = &s->refcount_block[cluster_offset >> s->cluster_bits]; |
533 | f7d0fe02 | Kevin Wolf | refcount = be16_to_cpu(*p); |
534 | f7d0fe02 | Kevin Wolf | refcount++; |
535 | f7d0fe02 | Kevin Wolf | *p = cpu_to_be16(refcount); |
536 | f7d0fe02 | Kevin Wolf | } |
537 | f7d0fe02 | Kevin Wolf | } |
538 | f7d0fe02 | Kevin Wolf | |
539 | f7d0fe02 | Kevin Wolf | /* update the refcounts of snapshots and the copied flag */
|
540 | ed6ccf0f | Kevin Wolf | int qcow2_update_snapshot_refcount(BlockDriverState *bs,
|
541 | ed6ccf0f | Kevin Wolf | int64_t l1_table_offset, int l1_size, int addend) |
542 | f7d0fe02 | Kevin Wolf | { |
543 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
544 | f7d0fe02 | Kevin Wolf | uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated; |
545 | f7d0fe02 | Kevin Wolf | int64_t old_offset, old_l2_offset; |
546 | f7d0fe02 | Kevin Wolf | int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount;
|
547 | f7d0fe02 | Kevin Wolf | |
548 | ed6ccf0f | Kevin Wolf | qcow2_l2_cache_reset(bs); |
549 | 3b88e52b | Kevin Wolf | cache_refcount_updates = 1;
|
550 | f7d0fe02 | Kevin Wolf | |
551 | f7d0fe02 | Kevin Wolf | l2_table = NULL;
|
552 | f7d0fe02 | Kevin Wolf | l1_table = NULL;
|
553 | f7d0fe02 | Kevin Wolf | l1_size2 = l1_size * sizeof(uint64_t);
|
554 | f7d0fe02 | Kevin Wolf | if (l1_table_offset != s->l1_table_offset) {
|
555 | 702ef63f | Kevin Wolf | if (l1_size2 != 0) { |
556 | 702ef63f | Kevin Wolf | l1_table = qemu_mallocz(align_offset(l1_size2, 512));
|
557 | 702ef63f | Kevin Wolf | } else {
|
558 | 702ef63f | Kevin Wolf | l1_table = NULL;
|
559 | 702ef63f | Kevin Wolf | } |
560 | f7d0fe02 | Kevin Wolf | l1_allocated = 1;
|
561 | f7d0fe02 | Kevin Wolf | if (bdrv_pread(s->hd, l1_table_offset,
|
562 | f7d0fe02 | Kevin Wolf | l1_table, l1_size2) != l1_size2) |
563 | f7d0fe02 | Kevin Wolf | goto fail;
|
564 | f7d0fe02 | Kevin Wolf | for(i = 0;i < l1_size; i++) |
565 | f7d0fe02 | Kevin Wolf | be64_to_cpus(&l1_table[i]); |
566 | f7d0fe02 | Kevin Wolf | } else {
|
567 | f7d0fe02 | Kevin Wolf | assert(l1_size == s->l1_size); |
568 | f7d0fe02 | Kevin Wolf | l1_table = s->l1_table; |
569 | f7d0fe02 | Kevin Wolf | l1_allocated = 0;
|
570 | f7d0fe02 | Kevin Wolf | } |
571 | f7d0fe02 | Kevin Wolf | |
572 | f7d0fe02 | Kevin Wolf | l2_size = s->l2_size * sizeof(uint64_t);
|
573 | f7d0fe02 | Kevin Wolf | l2_table = qemu_malloc(l2_size); |
574 | f7d0fe02 | Kevin Wolf | l1_modified = 0;
|
575 | f7d0fe02 | Kevin Wolf | for(i = 0; i < l1_size; i++) { |
576 | f7d0fe02 | Kevin Wolf | l2_offset = l1_table[i]; |
577 | f7d0fe02 | Kevin Wolf | if (l2_offset) {
|
578 | f7d0fe02 | Kevin Wolf | old_l2_offset = l2_offset; |
579 | f7d0fe02 | Kevin Wolf | l2_offset &= ~QCOW_OFLAG_COPIED; |
580 | f7d0fe02 | Kevin Wolf | l2_modified = 0;
|
581 | f7d0fe02 | Kevin Wolf | if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
|
582 | f7d0fe02 | Kevin Wolf | goto fail;
|
583 | f7d0fe02 | Kevin Wolf | for(j = 0; j < s->l2_size; j++) { |
584 | f7d0fe02 | Kevin Wolf | offset = be64_to_cpu(l2_table[j]); |
585 | f7d0fe02 | Kevin Wolf | if (offset != 0) { |
586 | f7d0fe02 | Kevin Wolf | old_offset = offset; |
587 | f7d0fe02 | Kevin Wolf | offset &= ~QCOW_OFLAG_COPIED; |
588 | f7d0fe02 | Kevin Wolf | if (offset & QCOW_OFLAG_COMPRESSED) {
|
589 | f7d0fe02 | Kevin Wolf | nb_csectors = ((offset >> s->csize_shift) & |
590 | f7d0fe02 | Kevin Wolf | s->csize_mask) + 1;
|
591 | db3a964f | Kevin Wolf | if (addend != 0) { |
592 | db3a964f | Kevin Wolf | int ret;
|
593 | db3a964f | Kevin Wolf | ret = update_refcount(bs, |
594 | db3a964f | Kevin Wolf | (offset & s->cluster_offset_mask) & ~511,
|
595 | db3a964f | Kevin Wolf | nb_csectors * 512, addend);
|
596 | db3a964f | Kevin Wolf | if (ret < 0) { |
597 | db3a964f | Kevin Wolf | goto fail;
|
598 | db3a964f | Kevin Wolf | } |
599 | db3a964f | Kevin Wolf | } |
600 | f7d0fe02 | Kevin Wolf | /* compressed clusters are never modified */
|
601 | f7d0fe02 | Kevin Wolf | refcount = 2;
|
602 | f7d0fe02 | Kevin Wolf | } else {
|
603 | f7d0fe02 | Kevin Wolf | if (addend != 0) { |
604 | f7d0fe02 | Kevin Wolf | refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend); |
605 | f7d0fe02 | Kevin Wolf | } else {
|
606 | f7d0fe02 | Kevin Wolf | refcount = get_refcount(bs, offset >> s->cluster_bits); |
607 | f7d0fe02 | Kevin Wolf | } |
608 | f7d0fe02 | Kevin Wolf | } |
609 | f7d0fe02 | Kevin Wolf | |
610 | f7d0fe02 | Kevin Wolf | if (refcount == 1) { |
611 | f7d0fe02 | Kevin Wolf | offset |= QCOW_OFLAG_COPIED; |
612 | f7d0fe02 | Kevin Wolf | } |
613 | f7d0fe02 | Kevin Wolf | if (offset != old_offset) {
|
614 | f7d0fe02 | Kevin Wolf | l2_table[j] = cpu_to_be64(offset); |
615 | f7d0fe02 | Kevin Wolf | l2_modified = 1;
|
616 | f7d0fe02 | Kevin Wolf | } |
617 | f7d0fe02 | Kevin Wolf | } |
618 | f7d0fe02 | Kevin Wolf | } |
619 | f7d0fe02 | Kevin Wolf | if (l2_modified) {
|
620 | f7d0fe02 | Kevin Wolf | if (bdrv_pwrite(s->hd,
|
621 | f7d0fe02 | Kevin Wolf | l2_offset, l2_table, l2_size) != l2_size) |
622 | f7d0fe02 | Kevin Wolf | goto fail;
|
623 | f7d0fe02 | Kevin Wolf | } |
624 | f7d0fe02 | Kevin Wolf | |
625 | f7d0fe02 | Kevin Wolf | if (addend != 0) { |
626 | f7d0fe02 | Kevin Wolf | refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend); |
627 | f7d0fe02 | Kevin Wolf | } else {
|
628 | f7d0fe02 | Kevin Wolf | refcount = get_refcount(bs, l2_offset >> s->cluster_bits); |
629 | f7d0fe02 | Kevin Wolf | } |
630 | f7d0fe02 | Kevin Wolf | if (refcount == 1) { |
631 | f7d0fe02 | Kevin Wolf | l2_offset |= QCOW_OFLAG_COPIED; |
632 | f7d0fe02 | Kevin Wolf | } |
633 | f7d0fe02 | Kevin Wolf | if (l2_offset != old_l2_offset) {
|
634 | f7d0fe02 | Kevin Wolf | l1_table[i] = l2_offset; |
635 | f7d0fe02 | Kevin Wolf | l1_modified = 1;
|
636 | f7d0fe02 | Kevin Wolf | } |
637 | f7d0fe02 | Kevin Wolf | } |
638 | f7d0fe02 | Kevin Wolf | } |
639 | f7d0fe02 | Kevin Wolf | if (l1_modified) {
|
640 | f7d0fe02 | Kevin Wolf | for(i = 0; i < l1_size; i++) |
641 | f7d0fe02 | Kevin Wolf | cpu_to_be64s(&l1_table[i]); |
642 | f7d0fe02 | Kevin Wolf | if (bdrv_pwrite(s->hd, l1_table_offset, l1_table,
|
643 | f7d0fe02 | Kevin Wolf | l1_size2) != l1_size2) |
644 | f7d0fe02 | Kevin Wolf | goto fail;
|
645 | f7d0fe02 | Kevin Wolf | for(i = 0; i < l1_size; i++) |
646 | f7d0fe02 | Kevin Wolf | be64_to_cpus(&l1_table[i]); |
647 | f7d0fe02 | Kevin Wolf | } |
648 | f7d0fe02 | Kevin Wolf | if (l1_allocated)
|
649 | f7d0fe02 | Kevin Wolf | qemu_free(l1_table); |
650 | f7d0fe02 | Kevin Wolf | qemu_free(l2_table); |
651 | 3b88e52b | Kevin Wolf | cache_refcount_updates = 0;
|
652 | 3b88e52b | Kevin Wolf | write_refcount_block(s); |
653 | f7d0fe02 | Kevin Wolf | return 0; |
654 | f7d0fe02 | Kevin Wolf | fail:
|
655 | f7d0fe02 | Kevin Wolf | if (l1_allocated)
|
656 | f7d0fe02 | Kevin Wolf | qemu_free(l1_table); |
657 | f7d0fe02 | Kevin Wolf | qemu_free(l2_table); |
658 | 3b88e52b | Kevin Wolf | cache_refcount_updates = 0;
|
659 | 3b88e52b | Kevin Wolf | write_refcount_block(s); |
660 | f7d0fe02 | Kevin Wolf | return -EIO;
|
661 | f7d0fe02 | Kevin Wolf | } |
662 | f7d0fe02 | Kevin Wolf | |
663 | f7d0fe02 | Kevin Wolf | |
664 | f7d0fe02 | Kevin Wolf | |
665 | f7d0fe02 | Kevin Wolf | |
666 | f7d0fe02 | Kevin Wolf | /*********************************************************/
|
667 | f7d0fe02 | Kevin Wolf | /* refcount checking functions */
|
668 | f7d0fe02 | Kevin Wolf | |
669 | f7d0fe02 | Kevin Wolf | |
670 | f7d0fe02 | Kevin Wolf | |
671 | f7d0fe02 | Kevin Wolf | /*
|
672 | f7d0fe02 | Kevin Wolf | * Increases the refcount for a range of clusters in a given refcount table.
|
673 | f7d0fe02 | Kevin Wolf | * This is used to construct a temporary refcount table out of L1 and L2 tables
|
674 | f7d0fe02 | Kevin Wolf | * which can be compared the the refcount table saved in the image.
|
675 | f7d0fe02 | Kevin Wolf | *
|
676 | f7d0fe02 | Kevin Wolf | * Returns the number of errors in the image that were found
|
677 | f7d0fe02 | Kevin Wolf | */
|
678 | f7d0fe02 | Kevin Wolf | static int inc_refcounts(BlockDriverState *bs, |
679 | f7d0fe02 | Kevin Wolf | uint16_t *refcount_table, |
680 | f7d0fe02 | Kevin Wolf | int refcount_table_size,
|
681 | f7d0fe02 | Kevin Wolf | int64_t offset, int64_t size) |
682 | f7d0fe02 | Kevin Wolf | { |
683 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
684 | f7d0fe02 | Kevin Wolf | int64_t start, last, cluster_offset; |
685 | f7d0fe02 | Kevin Wolf | int k;
|
686 | f7d0fe02 | Kevin Wolf | int errors = 0; |
687 | f7d0fe02 | Kevin Wolf | |
688 | f7d0fe02 | Kevin Wolf | if (size <= 0) |
689 | f7d0fe02 | Kevin Wolf | return 0; |
690 | f7d0fe02 | Kevin Wolf | |
691 | f7d0fe02 | Kevin Wolf | start = offset & ~(s->cluster_size - 1);
|
692 | f7d0fe02 | Kevin Wolf | last = (offset + size - 1) & ~(s->cluster_size - 1); |
693 | f7d0fe02 | Kevin Wolf | for(cluster_offset = start; cluster_offset <= last;
|
694 | f7d0fe02 | Kevin Wolf | cluster_offset += s->cluster_size) { |
695 | f7d0fe02 | Kevin Wolf | k = cluster_offset >> s->cluster_bits; |
696 | f7d0fe02 | Kevin Wolf | if (k < 0 || k >= refcount_table_size) { |
697 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n", |
698 | f7d0fe02 | Kevin Wolf | cluster_offset); |
699 | f7d0fe02 | Kevin Wolf | errors++; |
700 | f7d0fe02 | Kevin Wolf | } else {
|
701 | f7d0fe02 | Kevin Wolf | if (++refcount_table[k] == 0) { |
702 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
|
703 | f7d0fe02 | Kevin Wolf | "\n", cluster_offset);
|
704 | f7d0fe02 | Kevin Wolf | errors++; |
705 | f7d0fe02 | Kevin Wolf | } |
706 | f7d0fe02 | Kevin Wolf | } |
707 | f7d0fe02 | Kevin Wolf | } |
708 | f7d0fe02 | Kevin Wolf | |
709 | f7d0fe02 | Kevin Wolf | return errors;
|
710 | f7d0fe02 | Kevin Wolf | } |
711 | f7d0fe02 | Kevin Wolf | |
712 | f7d0fe02 | Kevin Wolf | /*
|
713 | f7d0fe02 | Kevin Wolf | * Increases the refcount in the given refcount table for the all clusters
|
714 | f7d0fe02 | Kevin Wolf | * referenced in the L2 table. While doing so, performs some checks on L2
|
715 | f7d0fe02 | Kevin Wolf | * entries.
|
716 | f7d0fe02 | Kevin Wolf | *
|
717 | f7d0fe02 | Kevin Wolf | * Returns the number of errors found by the checks or -errno if an internal
|
718 | f7d0fe02 | Kevin Wolf | * error occurred.
|
719 | f7d0fe02 | Kevin Wolf | */
|
720 | f7d0fe02 | Kevin Wolf | static int check_refcounts_l2(BlockDriverState *bs, |
721 | f7d0fe02 | Kevin Wolf | uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
|
722 | f7d0fe02 | Kevin Wolf | int check_copied)
|
723 | f7d0fe02 | Kevin Wolf | { |
724 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
725 | f7d0fe02 | Kevin Wolf | uint64_t *l2_table, offset; |
726 | f7d0fe02 | Kevin Wolf | int i, l2_size, nb_csectors, refcount;
|
727 | f7d0fe02 | Kevin Wolf | int errors = 0; |
728 | f7d0fe02 | Kevin Wolf | |
729 | f7d0fe02 | Kevin Wolf | /* Read L2 table from disk */
|
730 | f7d0fe02 | Kevin Wolf | l2_size = s->l2_size * sizeof(uint64_t);
|
731 | f7d0fe02 | Kevin Wolf | l2_table = qemu_malloc(l2_size); |
732 | f7d0fe02 | Kevin Wolf | |
733 | f7d0fe02 | Kevin Wolf | if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
|
734 | f7d0fe02 | Kevin Wolf | goto fail;
|
735 | f7d0fe02 | Kevin Wolf | |
736 | f7d0fe02 | Kevin Wolf | /* Do the actual checks */
|
737 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->l2_size; i++) { |
738 | f7d0fe02 | Kevin Wolf | offset = be64_to_cpu(l2_table[i]); |
739 | f7d0fe02 | Kevin Wolf | if (offset != 0) { |
740 | f7d0fe02 | Kevin Wolf | if (offset & QCOW_OFLAG_COMPRESSED) {
|
741 | f7d0fe02 | Kevin Wolf | /* Compressed clusters don't have QCOW_OFLAG_COPIED */
|
742 | f7d0fe02 | Kevin Wolf | if (offset & QCOW_OFLAG_COPIED) {
|
743 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR: cluster %" PRId64 ": " |
744 | f7d0fe02 | Kevin Wolf | "copied flag must never be set for compressed "
|
745 | f7d0fe02 | Kevin Wolf | "clusters\n", offset >> s->cluster_bits);
|
746 | f7d0fe02 | Kevin Wolf | offset &= ~QCOW_OFLAG_COPIED; |
747 | f7d0fe02 | Kevin Wolf | errors++; |
748 | f7d0fe02 | Kevin Wolf | } |
749 | f7d0fe02 | Kevin Wolf | |
750 | f7d0fe02 | Kevin Wolf | /* Mark cluster as used */
|
751 | f7d0fe02 | Kevin Wolf | nb_csectors = ((offset >> s->csize_shift) & |
752 | f7d0fe02 | Kevin Wolf | s->csize_mask) + 1;
|
753 | f7d0fe02 | Kevin Wolf | offset &= s->cluster_offset_mask; |
754 | f7d0fe02 | Kevin Wolf | errors += inc_refcounts(bs, refcount_table, |
755 | f7d0fe02 | Kevin Wolf | refcount_table_size, |
756 | f7d0fe02 | Kevin Wolf | offset & ~511, nb_csectors * 512); |
757 | f7d0fe02 | Kevin Wolf | } else {
|
758 | f7d0fe02 | Kevin Wolf | /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
|
759 | f7d0fe02 | Kevin Wolf | if (check_copied) {
|
760 | f7d0fe02 | Kevin Wolf | uint64_t entry = offset; |
761 | f7d0fe02 | Kevin Wolf | offset &= ~QCOW_OFLAG_COPIED; |
762 | f7d0fe02 | Kevin Wolf | refcount = get_refcount(bs, offset >> s->cluster_bits); |
763 | f7d0fe02 | Kevin Wolf | if ((refcount == 1) != ((entry & QCOW_OFLAG_COPIED) != 0)) { |
764 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
|
765 | f7d0fe02 | Kevin Wolf | PRIx64 " refcount=%d\n", entry, refcount);
|
766 | f7d0fe02 | Kevin Wolf | errors++; |
767 | f7d0fe02 | Kevin Wolf | } |
768 | f7d0fe02 | Kevin Wolf | } |
769 | f7d0fe02 | Kevin Wolf | |
770 | f7d0fe02 | Kevin Wolf | /* Mark cluster as used */
|
771 | f7d0fe02 | Kevin Wolf | offset &= ~QCOW_OFLAG_COPIED; |
772 | f7d0fe02 | Kevin Wolf | errors += inc_refcounts(bs, refcount_table, |
773 | f7d0fe02 | Kevin Wolf | refcount_table_size, |
774 | f7d0fe02 | Kevin Wolf | offset, s->cluster_size); |
775 | f7d0fe02 | Kevin Wolf | |
776 | f7d0fe02 | Kevin Wolf | /* Correct offsets are cluster aligned */
|
777 | f7d0fe02 | Kevin Wolf | if (offset & (s->cluster_size - 1)) { |
778 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not " |
779 | f7d0fe02 | Kevin Wolf | "properly aligned; L2 entry corrupted.\n", offset);
|
780 | f7d0fe02 | Kevin Wolf | errors++; |
781 | f7d0fe02 | Kevin Wolf | } |
782 | f7d0fe02 | Kevin Wolf | } |
783 | f7d0fe02 | Kevin Wolf | } |
784 | f7d0fe02 | Kevin Wolf | } |
785 | f7d0fe02 | Kevin Wolf | |
786 | f7d0fe02 | Kevin Wolf | qemu_free(l2_table); |
787 | f7d0fe02 | Kevin Wolf | return errors;
|
788 | f7d0fe02 | Kevin Wolf | |
789 | f7d0fe02 | Kevin Wolf | fail:
|
790 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
|
791 | f7d0fe02 | Kevin Wolf | qemu_free(l2_table); |
792 | f7d0fe02 | Kevin Wolf | return -EIO;
|
793 | f7d0fe02 | Kevin Wolf | } |
794 | f7d0fe02 | Kevin Wolf | |
795 | f7d0fe02 | Kevin Wolf | /*
|
796 | f7d0fe02 | Kevin Wolf | * Increases the refcount for the L1 table, its L2 tables and all referenced
|
797 | f7d0fe02 | Kevin Wolf | * clusters in the given refcount table. While doing so, performs some checks
|
798 | f7d0fe02 | Kevin Wolf | * on L1 and L2 entries.
|
799 | f7d0fe02 | Kevin Wolf | *
|
800 | f7d0fe02 | Kevin Wolf | * Returns the number of errors found by the checks or -errno if an internal
|
801 | f7d0fe02 | Kevin Wolf | * error occurred.
|
802 | f7d0fe02 | Kevin Wolf | */
|
803 | f7d0fe02 | Kevin Wolf | static int check_refcounts_l1(BlockDriverState *bs, |
804 | f7d0fe02 | Kevin Wolf | uint16_t *refcount_table, |
805 | f7d0fe02 | Kevin Wolf | int refcount_table_size,
|
806 | f7d0fe02 | Kevin Wolf | int64_t l1_table_offset, int l1_size,
|
807 | f7d0fe02 | Kevin Wolf | int check_copied)
|
808 | f7d0fe02 | Kevin Wolf | { |
809 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
810 | f7d0fe02 | Kevin Wolf | uint64_t *l1_table, l2_offset, l1_size2; |
811 | f7d0fe02 | Kevin Wolf | int i, refcount, ret;
|
812 | f7d0fe02 | Kevin Wolf | int errors = 0; |
813 | f7d0fe02 | Kevin Wolf | |
814 | f7d0fe02 | Kevin Wolf | l1_size2 = l1_size * sizeof(uint64_t);
|
815 | f7d0fe02 | Kevin Wolf | |
816 | f7d0fe02 | Kevin Wolf | /* Mark L1 table as used */
|
817 | f7d0fe02 | Kevin Wolf | errors += inc_refcounts(bs, refcount_table, refcount_table_size, |
818 | f7d0fe02 | Kevin Wolf | l1_table_offset, l1_size2); |
819 | f7d0fe02 | Kevin Wolf | |
820 | f7d0fe02 | Kevin Wolf | /* Read L1 table entries from disk */
|
821 | 702ef63f | Kevin Wolf | if (l1_size2 == 0) { |
822 | 702ef63f | Kevin Wolf | l1_table = NULL;
|
823 | 702ef63f | Kevin Wolf | } else {
|
824 | 702ef63f | Kevin Wolf | l1_table = qemu_malloc(l1_size2); |
825 | 702ef63f | Kevin Wolf | if (bdrv_pread(s->hd, l1_table_offset,
|
826 | 702ef63f | Kevin Wolf | l1_table, l1_size2) != l1_size2) |
827 | 702ef63f | Kevin Wolf | goto fail;
|
828 | 702ef63f | Kevin Wolf | for(i = 0;i < l1_size; i++) |
829 | 702ef63f | Kevin Wolf | be64_to_cpus(&l1_table[i]); |
830 | 702ef63f | Kevin Wolf | } |
831 | f7d0fe02 | Kevin Wolf | |
832 | f7d0fe02 | Kevin Wolf | /* Do the actual checks */
|
833 | f7d0fe02 | Kevin Wolf | for(i = 0; i < l1_size; i++) { |
834 | f7d0fe02 | Kevin Wolf | l2_offset = l1_table[i]; |
835 | f7d0fe02 | Kevin Wolf | if (l2_offset) {
|
836 | f7d0fe02 | Kevin Wolf | /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
|
837 | f7d0fe02 | Kevin Wolf | if (check_copied) {
|
838 | f7d0fe02 | Kevin Wolf | refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED) |
839 | f7d0fe02 | Kevin Wolf | >> s->cluster_bits); |
840 | f7d0fe02 | Kevin Wolf | if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { |
841 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
|
842 | f7d0fe02 | Kevin Wolf | " refcount=%d\n", l2_offset, refcount);
|
843 | f7d0fe02 | Kevin Wolf | errors++; |
844 | f7d0fe02 | Kevin Wolf | } |
845 | f7d0fe02 | Kevin Wolf | } |
846 | f7d0fe02 | Kevin Wolf | |
847 | f7d0fe02 | Kevin Wolf | /* Mark L2 table as used */
|
848 | f7d0fe02 | Kevin Wolf | l2_offset &= ~QCOW_OFLAG_COPIED; |
849 | f7d0fe02 | Kevin Wolf | errors += inc_refcounts(bs, refcount_table, |
850 | f7d0fe02 | Kevin Wolf | refcount_table_size, |
851 | f7d0fe02 | Kevin Wolf | l2_offset, |
852 | f7d0fe02 | Kevin Wolf | s->cluster_size); |
853 | f7d0fe02 | Kevin Wolf | |
854 | f7d0fe02 | Kevin Wolf | /* L2 tables are cluster aligned */
|
855 | f7d0fe02 | Kevin Wolf | if (l2_offset & (s->cluster_size - 1)) { |
856 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not " |
857 | f7d0fe02 | Kevin Wolf | "cluster aligned; L1 entry corrupted\n", l2_offset);
|
858 | f7d0fe02 | Kevin Wolf | errors++; |
859 | f7d0fe02 | Kevin Wolf | } |
860 | f7d0fe02 | Kevin Wolf | |
861 | f7d0fe02 | Kevin Wolf | /* Process and check L2 entries */
|
862 | f7d0fe02 | Kevin Wolf | ret = check_refcounts_l2(bs, refcount_table, refcount_table_size, |
863 | f7d0fe02 | Kevin Wolf | l2_offset, check_copied); |
864 | f7d0fe02 | Kevin Wolf | if (ret < 0) { |
865 | f7d0fe02 | Kevin Wolf | goto fail;
|
866 | f7d0fe02 | Kevin Wolf | } |
867 | f7d0fe02 | Kevin Wolf | errors += ret; |
868 | f7d0fe02 | Kevin Wolf | } |
869 | f7d0fe02 | Kevin Wolf | } |
870 | f7d0fe02 | Kevin Wolf | qemu_free(l1_table); |
871 | f7d0fe02 | Kevin Wolf | return errors;
|
872 | f7d0fe02 | Kevin Wolf | |
873 | f7d0fe02 | Kevin Wolf | fail:
|
874 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
|
875 | f7d0fe02 | Kevin Wolf | qemu_free(l1_table); |
876 | f7d0fe02 | Kevin Wolf | return -EIO;
|
877 | f7d0fe02 | Kevin Wolf | } |
878 | f7d0fe02 | Kevin Wolf | |
879 | f7d0fe02 | Kevin Wolf | /*
|
880 | f7d0fe02 | Kevin Wolf | * Checks an image for refcount consistency.
|
881 | f7d0fe02 | Kevin Wolf | *
|
882 | f7d0fe02 | Kevin Wolf | * Returns 0 if no errors are found, the number of errors in case the image is
|
883 | f7d0fe02 | Kevin Wolf | * detected as corrupted, and -errno when an internal error occured.
|
884 | f7d0fe02 | Kevin Wolf | */
|
885 | ed6ccf0f | Kevin Wolf | int qcow2_check_refcounts(BlockDriverState *bs)
|
886 | f7d0fe02 | Kevin Wolf | { |
887 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
888 | f7d0fe02 | Kevin Wolf | int64_t size; |
889 | f7d0fe02 | Kevin Wolf | int nb_clusters, refcount1, refcount2, i;
|
890 | f7d0fe02 | Kevin Wolf | QCowSnapshot *sn; |
891 | f7d0fe02 | Kevin Wolf | uint16_t *refcount_table; |
892 | f7d0fe02 | Kevin Wolf | int ret, errors = 0; |
893 | f7d0fe02 | Kevin Wolf | |
894 | f7d0fe02 | Kevin Wolf | size = bdrv_getlength(s->hd); |
895 | f7d0fe02 | Kevin Wolf | nb_clusters = size_to_clusters(s, size); |
896 | f7d0fe02 | Kevin Wolf | refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t));
|
897 | f7d0fe02 | Kevin Wolf | |
898 | f7d0fe02 | Kevin Wolf | /* header */
|
899 | f7d0fe02 | Kevin Wolf | errors += inc_refcounts(bs, refcount_table, nb_clusters, |
900 | f7d0fe02 | Kevin Wolf | 0, s->cluster_size);
|
901 | f7d0fe02 | Kevin Wolf | |
902 | f7d0fe02 | Kevin Wolf | /* current L1 table */
|
903 | f7d0fe02 | Kevin Wolf | ret = check_refcounts_l1(bs, refcount_table, nb_clusters, |
904 | f7d0fe02 | Kevin Wolf | s->l1_table_offset, s->l1_size, 1);
|
905 | f7d0fe02 | Kevin Wolf | if (ret < 0) { |
906 | f7d0fe02 | Kevin Wolf | return ret;
|
907 | f7d0fe02 | Kevin Wolf | } |
908 | f7d0fe02 | Kevin Wolf | errors += ret; |
909 | f7d0fe02 | Kevin Wolf | |
910 | f7d0fe02 | Kevin Wolf | /* snapshots */
|
911 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->nb_snapshots; i++) { |
912 | f7d0fe02 | Kevin Wolf | sn = s->snapshots + i; |
913 | f7d0fe02 | Kevin Wolf | check_refcounts_l1(bs, refcount_table, nb_clusters, |
914 | f7d0fe02 | Kevin Wolf | sn->l1_table_offset, sn->l1_size, 0);
|
915 | f7d0fe02 | Kevin Wolf | } |
916 | f7d0fe02 | Kevin Wolf | errors += inc_refcounts(bs, refcount_table, nb_clusters, |
917 | f7d0fe02 | Kevin Wolf | s->snapshots_offset, s->snapshots_size); |
918 | f7d0fe02 | Kevin Wolf | |
919 | f7d0fe02 | Kevin Wolf | /* refcount data */
|
920 | f7d0fe02 | Kevin Wolf | errors += inc_refcounts(bs, refcount_table, nb_clusters, |
921 | f7d0fe02 | Kevin Wolf | s->refcount_table_offset, |
922 | f7d0fe02 | Kevin Wolf | s->refcount_table_size * sizeof(uint64_t));
|
923 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->refcount_table_size; i++) { |
924 | f7d0fe02 | Kevin Wolf | int64_t offset; |
925 | f7d0fe02 | Kevin Wolf | offset = s->refcount_table[i]; |
926 | f7d0fe02 | Kevin Wolf | if (offset != 0) { |
927 | f7d0fe02 | Kevin Wolf | errors += inc_refcounts(bs, refcount_table, nb_clusters, |
928 | f7d0fe02 | Kevin Wolf | offset, s->cluster_size); |
929 | f7d0fe02 | Kevin Wolf | } |
930 | f7d0fe02 | Kevin Wolf | } |
931 | f7d0fe02 | Kevin Wolf | |
932 | f7d0fe02 | Kevin Wolf | /* compare ref counts */
|
933 | f7d0fe02 | Kevin Wolf | for(i = 0; i < nb_clusters; i++) { |
934 | f7d0fe02 | Kevin Wolf | refcount1 = get_refcount(bs, i); |
935 | f7d0fe02 | Kevin Wolf | refcount2 = refcount_table[i]; |
936 | f7d0fe02 | Kevin Wolf | if (refcount1 != refcount2) {
|
937 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR cluster %d refcount=%d reference=%d\n",
|
938 | f7d0fe02 | Kevin Wolf | i, refcount1, refcount2); |
939 | f7d0fe02 | Kevin Wolf | errors++; |
940 | f7d0fe02 | Kevin Wolf | } |
941 | f7d0fe02 | Kevin Wolf | } |
942 | f7d0fe02 | Kevin Wolf | |
943 | f7d0fe02 | Kevin Wolf | qemu_free(refcount_table); |
944 | f7d0fe02 | Kevin Wolf | |
945 | f7d0fe02 | Kevin Wolf | return errors;
|
946 | f7d0fe02 | Kevin Wolf | } |