root / block / qcow2-refcount.c @ 206e6d85
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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 | 92dcb59f | Kevin Wolf | static int QEMU_WARN_UNUSED_RESULT 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 | f7d0fe02 | Kevin Wolf | /*********************************************************/
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36 | f7d0fe02 | Kevin Wolf | /* refcount handling */
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37 | f7d0fe02 | Kevin Wolf | |
38 | ed6ccf0f | Kevin Wolf | int qcow2_refcount_init(BlockDriverState *bs)
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39 | f7d0fe02 | Kevin Wolf | { |
40 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
41 | f7d0fe02 | Kevin Wolf | int ret, refcount_table_size2, i;
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42 | f7d0fe02 | Kevin Wolf | |
43 | f7d0fe02 | Kevin Wolf | refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
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44 | 7267c094 | Anthony Liguori | s->refcount_table = g_malloc(refcount_table_size2); |
45 | f7d0fe02 | Kevin Wolf | if (s->refcount_table_size > 0) { |
46 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_LOAD); |
47 | 66f82cee | Kevin Wolf | ret = bdrv_pread(bs->file, s->refcount_table_offset, |
48 | f7d0fe02 | Kevin Wolf | s->refcount_table, refcount_table_size2); |
49 | f7d0fe02 | Kevin Wolf | if (ret != refcount_table_size2)
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50 | f7d0fe02 | Kevin Wolf | goto fail;
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51 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->refcount_table_size; i++) |
52 | f7d0fe02 | Kevin Wolf | be64_to_cpus(&s->refcount_table[i]); |
53 | f7d0fe02 | Kevin Wolf | } |
54 | f7d0fe02 | Kevin Wolf | return 0; |
55 | f7d0fe02 | Kevin Wolf | fail:
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56 | f7d0fe02 | Kevin Wolf | return -ENOMEM;
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57 | f7d0fe02 | Kevin Wolf | } |
58 | f7d0fe02 | Kevin Wolf | |
59 | ed6ccf0f | Kevin Wolf | void qcow2_refcount_close(BlockDriverState *bs)
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60 | f7d0fe02 | Kevin Wolf | { |
61 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
62 | 7267c094 | Anthony Liguori | g_free(s->refcount_table); |
63 | f7d0fe02 | Kevin Wolf | } |
64 | f7d0fe02 | Kevin Wolf | |
65 | f7d0fe02 | Kevin Wolf | |
66 | f7d0fe02 | Kevin Wolf | static int load_refcount_block(BlockDriverState *bs, |
67 | 29c1a730 | Kevin Wolf | int64_t refcount_block_offset, |
68 | 29c1a730 | Kevin Wolf | void **refcount_block)
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69 | f7d0fe02 | Kevin Wolf | { |
70 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
71 | f7d0fe02 | Kevin Wolf | int ret;
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72 | 3b88e52b | Kevin Wolf | |
73 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_LOAD); |
74 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_get(bs, s->refcount_block_cache, refcount_block_offset, |
75 | 29c1a730 | Kevin Wolf | refcount_block); |
76 | e14e8ba5 | Kevin Wolf | |
77 | 29c1a730 | Kevin Wolf | return ret;
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78 | f7d0fe02 | Kevin Wolf | } |
79 | f7d0fe02 | Kevin Wolf | |
80 | 018faafd | Kevin Wolf | /*
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81 | 018faafd | Kevin Wolf | * Returns the refcount of the cluster given by its index. Any non-negative
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82 | 018faafd | Kevin Wolf | * return value is the refcount of the cluster, negative values are -errno
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83 | 018faafd | Kevin Wolf | * and indicate an error.
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84 | 018faafd | Kevin Wolf | */
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85 | f7d0fe02 | Kevin Wolf | static int get_refcount(BlockDriverState *bs, int64_t cluster_index) |
86 | f7d0fe02 | Kevin Wolf | { |
87 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
88 | f7d0fe02 | Kevin Wolf | int refcount_table_index, block_index;
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89 | f7d0fe02 | Kevin Wolf | int64_t refcount_block_offset; |
90 | 018faafd | Kevin Wolf | int ret;
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91 | 29c1a730 | Kevin Wolf | uint16_t *refcount_block; |
92 | 29c1a730 | Kevin Wolf | uint16_t refcount; |
93 | f7d0fe02 | Kevin Wolf | |
94 | f7d0fe02 | Kevin Wolf | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
95 | f7d0fe02 | Kevin Wolf | if (refcount_table_index >= s->refcount_table_size)
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96 | f7d0fe02 | Kevin Wolf | return 0; |
97 | f7d0fe02 | Kevin Wolf | refcount_block_offset = s->refcount_table[refcount_table_index]; |
98 | f7d0fe02 | Kevin Wolf | if (!refcount_block_offset)
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99 | f7d0fe02 | Kevin Wolf | return 0; |
100 | 29c1a730 | Kevin Wolf | |
101 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_get(bs, s->refcount_block_cache, refcount_block_offset, |
102 | 29c1a730 | Kevin Wolf | (void**) &refcount_block);
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103 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
104 | 29c1a730 | Kevin Wolf | return ret;
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105 | f7d0fe02 | Kevin Wolf | } |
106 | 29c1a730 | Kevin Wolf | |
107 | f7d0fe02 | Kevin Wolf | block_index = cluster_index & |
108 | f7d0fe02 | Kevin Wolf | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
109 | 29c1a730 | Kevin Wolf | refcount = be16_to_cpu(refcount_block[block_index]); |
110 | 29c1a730 | Kevin Wolf | |
111 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_put(bs, s->refcount_block_cache, |
112 | 29c1a730 | Kevin Wolf | (void**) &refcount_block);
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113 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
114 | 29c1a730 | Kevin Wolf | return ret;
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115 | 29c1a730 | Kevin Wolf | } |
116 | 29c1a730 | Kevin Wolf | |
117 | 29c1a730 | Kevin Wolf | return refcount;
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118 | f7d0fe02 | Kevin Wolf | } |
119 | f7d0fe02 | Kevin Wolf | |
120 | 05121aed | Kevin Wolf | /*
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121 | 05121aed | Kevin Wolf | * Rounds the refcount table size up to avoid growing the table for each single
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122 | 05121aed | Kevin Wolf | * refcount block that is allocated.
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123 | 05121aed | Kevin Wolf | */
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124 | 05121aed | Kevin Wolf | static unsigned int next_refcount_table_size(BDRVQcowState *s, |
125 | 05121aed | Kevin Wolf | unsigned int min_size) |
126 | 05121aed | Kevin Wolf | { |
127 | 05121aed | Kevin Wolf | unsigned int min_clusters = (min_size >> (s->cluster_bits - 3)) + 1; |
128 | 05121aed | Kevin Wolf | unsigned int refcount_table_clusters = |
129 | 05121aed | Kevin Wolf | MAX(1, s->refcount_table_size >> (s->cluster_bits - 3)); |
130 | 05121aed | Kevin Wolf | |
131 | 05121aed | Kevin Wolf | while (min_clusters > refcount_table_clusters) {
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132 | 05121aed | Kevin Wolf | refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2; |
133 | 05121aed | Kevin Wolf | } |
134 | 05121aed | Kevin Wolf | |
135 | 05121aed | Kevin Wolf | return refcount_table_clusters << (s->cluster_bits - 3); |
136 | 05121aed | Kevin Wolf | } |
137 | 05121aed | Kevin Wolf | |
138 | 92dcb59f | Kevin Wolf | |
139 | 92dcb59f | Kevin Wolf | /* Checks if two offsets are described by the same refcount block */
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140 | 92dcb59f | Kevin Wolf | static int in_same_refcount_block(BDRVQcowState *s, uint64_t offset_a, |
141 | 92dcb59f | Kevin Wolf | uint64_t offset_b) |
142 | 92dcb59f | Kevin Wolf | { |
143 | 92dcb59f | Kevin Wolf | uint64_t block_a = offset_a >> (2 * s->cluster_bits - REFCOUNT_SHIFT);
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144 | 92dcb59f | Kevin Wolf | uint64_t block_b = offset_b >> (2 * s->cluster_bits - REFCOUNT_SHIFT);
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145 | 92dcb59f | Kevin Wolf | |
146 | 92dcb59f | Kevin Wolf | return (block_a == block_b);
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147 | 92dcb59f | Kevin Wolf | } |
148 | 92dcb59f | Kevin Wolf | |
149 | 92dcb59f | Kevin Wolf | /*
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150 | 92dcb59f | Kevin Wolf | * Loads a refcount block. If it doesn't exist yet, it is allocated first
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151 | 92dcb59f | Kevin Wolf | * (including growing the refcount table if needed).
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152 | 92dcb59f | Kevin Wolf | *
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153 | 29c1a730 | Kevin Wolf | * Returns 0 on success or -errno in error case
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154 | 92dcb59f | Kevin Wolf | */
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155 | 29c1a730 | Kevin Wolf | static int alloc_refcount_block(BlockDriverState *bs, |
156 | 29c1a730 | Kevin Wolf | int64_t cluster_index, uint16_t **refcount_block) |
157 | f7d0fe02 | Kevin Wolf | { |
158 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
159 | 92dcb59f | Kevin Wolf | unsigned int refcount_table_index; |
160 | 92dcb59f | Kevin Wolf | int ret;
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161 | 92dcb59f | Kevin Wolf | |
162 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC); |
163 | 8252278a | Kevin Wolf | |
164 | 92dcb59f | Kevin Wolf | /* Find the refcount block for the given cluster */
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165 | 92dcb59f | Kevin Wolf | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
166 | 92dcb59f | Kevin Wolf | |
167 | 92dcb59f | Kevin Wolf | if (refcount_table_index < s->refcount_table_size) {
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168 | 92dcb59f | Kevin Wolf | |
169 | 92dcb59f | Kevin Wolf | uint64_t refcount_block_offset = |
170 | 76dc9e0c | Kevin Wolf | s->refcount_table[refcount_table_index] & REFT_OFFSET_MASK; |
171 | 92dcb59f | Kevin Wolf | |
172 | 92dcb59f | Kevin Wolf | /* If it's already there, we're done */
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173 | 92dcb59f | Kevin Wolf | if (refcount_block_offset) {
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174 | 29c1a730 | Kevin Wolf | return load_refcount_block(bs, refcount_block_offset,
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175 | 29c1a730 | Kevin Wolf | (void**) refcount_block);
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176 | 92dcb59f | Kevin Wolf | } |
177 | 92dcb59f | Kevin Wolf | } |
178 | 92dcb59f | Kevin Wolf | |
179 | 92dcb59f | Kevin Wolf | /*
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180 | 92dcb59f | Kevin Wolf | * If we came here, we need to allocate something. Something is at least
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181 | 92dcb59f | Kevin Wolf | * a cluster for the new refcount block. It may also include a new refcount
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182 | 92dcb59f | Kevin Wolf | * table if the old refcount table is too small.
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183 | 92dcb59f | Kevin Wolf | *
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184 | 92dcb59f | Kevin Wolf | * Note that allocating clusters here needs some special care:
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185 | 92dcb59f | Kevin Wolf | *
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186 | 92dcb59f | Kevin Wolf | * - We can't use the normal qcow2_alloc_clusters(), it would try to
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187 | 92dcb59f | Kevin Wolf | * increase the refcount and very likely we would end up with an endless
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188 | 92dcb59f | Kevin Wolf | * recursion. Instead we must place the refcount blocks in a way that
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189 | 92dcb59f | Kevin Wolf | * they can describe them themselves.
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190 | 92dcb59f | Kevin Wolf | *
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191 | 92dcb59f | Kevin Wolf | * - We need to consider that at this point we are inside update_refcounts
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192 | 92dcb59f | Kevin Wolf | * and doing the initial refcount increase. This means that some clusters
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193 | 92dcb59f | Kevin Wolf | * have already been allocated by the caller, but their refcount isn't
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194 | 92dcb59f | Kevin Wolf | * accurate yet. free_cluster_index tells us where this allocation ends
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195 | 92dcb59f | Kevin Wolf | * as long as we don't overwrite it by freeing clusters.
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196 | 92dcb59f | Kevin Wolf | *
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197 | 92dcb59f | Kevin Wolf | * - alloc_clusters_noref and qcow2_free_clusters may load a different
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198 | 92dcb59f | Kevin Wolf | * refcount block into the cache
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199 | 92dcb59f | Kevin Wolf | */
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200 | 92dcb59f | Kevin Wolf | |
201 | 29c1a730 | Kevin Wolf | *refcount_block = NULL;
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202 | 29c1a730 | Kevin Wolf | |
203 | 29c1a730 | Kevin Wolf | /* We write to the refcount table, so we might depend on L2 tables */
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204 | 29c1a730 | Kevin Wolf | qcow2_cache_flush(bs, s->l2_table_cache); |
205 | 92dcb59f | Kevin Wolf | |
206 | 92dcb59f | Kevin Wolf | /* Allocate the refcount block itself and mark it as used */
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207 | 2eaa8f63 | Kevin Wolf | int64_t new_block = alloc_clusters_noref(bs, s->cluster_size); |
208 | 2eaa8f63 | Kevin Wolf | if (new_block < 0) { |
209 | 2eaa8f63 | Kevin Wolf | return new_block;
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210 | 2eaa8f63 | Kevin Wolf | } |
211 | f7d0fe02 | Kevin Wolf | |
212 | f7d0fe02 | Kevin Wolf | #ifdef DEBUG_ALLOC2
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213 | 92dcb59f | Kevin Wolf | fprintf(stderr, "qcow2: Allocate refcount block %d for %" PRIx64
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214 | 92dcb59f | Kevin Wolf | " at %" PRIx64 "\n", |
215 | 92dcb59f | Kevin Wolf | refcount_table_index, cluster_index << s->cluster_bits, new_block); |
216 | f7d0fe02 | Kevin Wolf | #endif
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217 | 92dcb59f | Kevin Wolf | |
218 | 92dcb59f | Kevin Wolf | if (in_same_refcount_block(s, new_block, cluster_index << s->cluster_bits)) {
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219 | 25408c09 | Kevin Wolf | /* Zero the new refcount block before updating it */
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220 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_get_empty(bs, s->refcount_block_cache, new_block, |
221 | 29c1a730 | Kevin Wolf | (void**) refcount_block);
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222 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
223 | 29c1a730 | Kevin Wolf | goto fail_block;
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224 | 29c1a730 | Kevin Wolf | } |
225 | 29c1a730 | Kevin Wolf | |
226 | 29c1a730 | Kevin Wolf | memset(*refcount_block, 0, s->cluster_size);
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227 | 25408c09 | Kevin Wolf | |
228 | 92dcb59f | Kevin Wolf | /* The block describes itself, need to update the cache */
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229 | 92dcb59f | Kevin Wolf | int block_index = (new_block >> s->cluster_bits) &
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230 | 92dcb59f | Kevin Wolf | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
231 | 29c1a730 | Kevin Wolf | (*refcount_block)[block_index] = cpu_to_be16(1);
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232 | 92dcb59f | Kevin Wolf | } else {
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233 | 92dcb59f | Kevin Wolf | /* Described somewhere else. This can recurse at most twice before we
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234 | 92dcb59f | Kevin Wolf | * arrive at a block that describes itself. */
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235 | 92dcb59f | Kevin Wolf | ret = update_refcount(bs, new_block, s->cluster_size, 1);
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236 | 92dcb59f | Kevin Wolf | if (ret < 0) { |
237 | 92dcb59f | Kevin Wolf | goto fail_block;
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238 | 92dcb59f | Kevin Wolf | } |
239 | 25408c09 | Kevin Wolf | |
240 | 1c4c2814 | Kevin Wolf | bdrv_flush(bs->file); |
241 | 1c4c2814 | Kevin Wolf | |
242 | 25408c09 | Kevin Wolf | /* Initialize the new refcount block only after updating its refcount,
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243 | 25408c09 | Kevin Wolf | * update_refcount uses the refcount cache itself */
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244 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_get_empty(bs, s->refcount_block_cache, new_block, |
245 | 29c1a730 | Kevin Wolf | (void**) refcount_block);
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246 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
247 | 29c1a730 | Kevin Wolf | goto fail_block;
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248 | 29c1a730 | Kevin Wolf | } |
249 | 29c1a730 | Kevin Wolf | |
250 | 29c1a730 | Kevin Wolf | memset(*refcount_block, 0, s->cluster_size);
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251 | 92dcb59f | Kevin Wolf | } |
252 | 92dcb59f | Kevin Wolf | |
253 | 92dcb59f | Kevin Wolf | /* Now the new refcount block needs to be written to disk */
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254 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE); |
255 | 29c1a730 | Kevin Wolf | qcow2_cache_entry_mark_dirty(s->refcount_block_cache, *refcount_block); |
256 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_flush(bs, s->refcount_block_cache); |
257 | 92dcb59f | Kevin Wolf | if (ret < 0) { |
258 | 92dcb59f | Kevin Wolf | goto fail_block;
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259 | 92dcb59f | Kevin Wolf | } |
260 | 92dcb59f | Kevin Wolf | |
261 | 92dcb59f | Kevin Wolf | /* If the refcount table is big enough, just hook the block up there */
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262 | 92dcb59f | Kevin Wolf | if (refcount_table_index < s->refcount_table_size) {
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263 | 92dcb59f | Kevin Wolf | uint64_t data64 = cpu_to_be64(new_block); |
264 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_HOOKUP); |
265 | 8b3b7206 | Kevin Wolf | ret = bdrv_pwrite_sync(bs->file, |
266 | 92dcb59f | Kevin Wolf | s->refcount_table_offset + refcount_table_index * sizeof(uint64_t),
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267 | 92dcb59f | Kevin Wolf | &data64, sizeof(data64));
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268 | 92dcb59f | Kevin Wolf | if (ret < 0) { |
269 | 92dcb59f | Kevin Wolf | goto fail_block;
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270 | 92dcb59f | Kevin Wolf | } |
271 | 92dcb59f | Kevin Wolf | |
272 | 92dcb59f | Kevin Wolf | s->refcount_table[refcount_table_index] = new_block; |
273 | 29c1a730 | Kevin Wolf | return 0; |
274 | 29c1a730 | Kevin Wolf | } |
275 | 29c1a730 | Kevin Wolf | |
276 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block);
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277 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
278 | 29c1a730 | Kevin Wolf | goto fail_block;
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279 | 92dcb59f | Kevin Wolf | } |
280 | 92dcb59f | Kevin Wolf | |
281 | 92dcb59f | Kevin Wolf | /*
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282 | 92dcb59f | Kevin Wolf | * If we come here, we need to grow the refcount table. Again, a new
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283 | 92dcb59f | Kevin Wolf | * refcount table needs some space and we can't simply allocate to avoid
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284 | 92dcb59f | Kevin Wolf | * endless recursion.
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285 | 92dcb59f | Kevin Wolf | *
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286 | 92dcb59f | Kevin Wolf | * Therefore let's grab new refcount blocks at the end of the image, which
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287 | 92dcb59f | Kevin Wolf | * will describe themselves and the new refcount table. This way we can
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288 | 92dcb59f | Kevin Wolf | * reference them only in the new table and do the switch to the new
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289 | 92dcb59f | Kevin Wolf | * refcount table at once without producing an inconsistent state in
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290 | 92dcb59f | Kevin Wolf | * between.
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291 | 92dcb59f | Kevin Wolf | */
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292 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_GROW); |
293 | 8252278a | Kevin Wolf | |
294 | 92dcb59f | Kevin Wolf | /* Calculate the number of refcount blocks needed so far */
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295 | 92dcb59f | Kevin Wolf | uint64_t refcount_block_clusters = 1 << (s->cluster_bits - REFCOUNT_SHIFT);
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296 | 92dcb59f | Kevin Wolf | uint64_t blocks_used = (s->free_cluster_index + |
297 | 92dcb59f | Kevin Wolf | refcount_block_clusters - 1) / refcount_block_clusters;
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298 | 92dcb59f | Kevin Wolf | |
299 | 92dcb59f | Kevin Wolf | /* And now we need at least one block more for the new metadata */
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300 | 92dcb59f | Kevin Wolf | uint64_t table_size = next_refcount_table_size(s, blocks_used + 1);
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301 | 92dcb59f | Kevin Wolf | uint64_t last_table_size; |
302 | 92dcb59f | Kevin Wolf | uint64_t blocks_clusters; |
303 | 92dcb59f | Kevin Wolf | do {
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304 | 92dcb59f | Kevin Wolf | uint64_t table_clusters = size_to_clusters(s, table_size); |
305 | 92dcb59f | Kevin Wolf | blocks_clusters = 1 +
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306 | 92dcb59f | Kevin Wolf | ((table_clusters + refcount_block_clusters - 1)
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307 | 92dcb59f | Kevin Wolf | / refcount_block_clusters); |
308 | 92dcb59f | Kevin Wolf | uint64_t meta_clusters = table_clusters + blocks_clusters; |
309 | 92dcb59f | Kevin Wolf | |
310 | 92dcb59f | Kevin Wolf | last_table_size = table_size; |
311 | 92dcb59f | Kevin Wolf | table_size = next_refcount_table_size(s, blocks_used + |
312 | 92dcb59f | Kevin Wolf | ((meta_clusters + refcount_block_clusters - 1)
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313 | 92dcb59f | Kevin Wolf | / refcount_block_clusters)); |
314 | 92dcb59f | Kevin Wolf | |
315 | 92dcb59f | Kevin Wolf | } while (last_table_size != table_size);
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316 | 92dcb59f | Kevin Wolf | |
317 | 92dcb59f | Kevin Wolf | #ifdef DEBUG_ALLOC2
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318 | 92dcb59f | Kevin Wolf | fprintf(stderr, "qcow2: Grow refcount table %" PRId32 " => %" PRId64 "\n", |
319 | 92dcb59f | Kevin Wolf | s->refcount_table_size, table_size); |
320 | 92dcb59f | Kevin Wolf | #endif
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321 | 92dcb59f | Kevin Wolf | |
322 | 92dcb59f | Kevin Wolf | /* Create the new refcount table and blocks */
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323 | 92dcb59f | Kevin Wolf | uint64_t meta_offset = (blocks_used * refcount_block_clusters) * |
324 | 92dcb59f | Kevin Wolf | s->cluster_size; |
325 | 92dcb59f | Kevin Wolf | uint64_t table_offset = meta_offset + blocks_clusters * s->cluster_size; |
326 | 7267c094 | Anthony Liguori | uint16_t *new_blocks = g_malloc0(blocks_clusters * s->cluster_size); |
327 | 7267c094 | Anthony Liguori | uint64_t *new_table = g_malloc0(table_size * sizeof(uint64_t));
|
328 | 92dcb59f | Kevin Wolf | |
329 | 92dcb59f | Kevin Wolf | assert(meta_offset >= (s->free_cluster_index * s->cluster_size)); |
330 | 92dcb59f | Kevin Wolf | |
331 | 92dcb59f | Kevin Wolf | /* Fill the new refcount table */
|
332 | f7d0fe02 | Kevin Wolf | memcpy(new_table, s->refcount_table, |
333 | 92dcb59f | Kevin Wolf | s->refcount_table_size * sizeof(uint64_t));
|
334 | 92dcb59f | Kevin Wolf | new_table[refcount_table_index] = new_block; |
335 | 92dcb59f | Kevin Wolf | |
336 | 92dcb59f | Kevin Wolf | int i;
|
337 | 92dcb59f | Kevin Wolf | for (i = 0; i < blocks_clusters; i++) { |
338 | 92dcb59f | Kevin Wolf | new_table[blocks_used + i] = meta_offset + (i * s->cluster_size); |
339 | 92dcb59f | Kevin Wolf | } |
340 | 92dcb59f | Kevin Wolf | |
341 | 92dcb59f | Kevin Wolf | /* Fill the refcount blocks */
|
342 | 92dcb59f | Kevin Wolf | uint64_t table_clusters = size_to_clusters(s, table_size * sizeof(uint64_t));
|
343 | 92dcb59f | Kevin Wolf | int block = 0; |
344 | 92dcb59f | Kevin Wolf | for (i = 0; i < table_clusters + blocks_clusters; i++) { |
345 | 92dcb59f | Kevin Wolf | new_blocks[block++] = cpu_to_be16(1);
|
346 | 92dcb59f | Kevin Wolf | } |
347 | 92dcb59f | Kevin Wolf | |
348 | 92dcb59f | Kevin Wolf | /* Write refcount blocks to disk */
|
349 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS); |
350 | 8b3b7206 | Kevin Wolf | ret = bdrv_pwrite_sync(bs->file, meta_offset, new_blocks, |
351 | 92dcb59f | Kevin Wolf | blocks_clusters * s->cluster_size); |
352 | 7267c094 | Anthony Liguori | g_free(new_blocks); |
353 | 92dcb59f | Kevin Wolf | if (ret < 0) { |
354 | 92dcb59f | Kevin Wolf | goto fail_table;
|
355 | 92dcb59f | Kevin Wolf | } |
356 | 92dcb59f | Kevin Wolf | |
357 | 92dcb59f | Kevin Wolf | /* Write refcount table to disk */
|
358 | 92dcb59f | Kevin Wolf | for(i = 0; i < table_size; i++) { |
359 | 92dcb59f | Kevin Wolf | cpu_to_be64s(&new_table[i]); |
360 | 92dcb59f | Kevin Wolf | } |
361 | 92dcb59f | Kevin Wolf | |
362 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE); |
363 | 8b3b7206 | Kevin Wolf | ret = bdrv_pwrite_sync(bs->file, table_offset, new_table, |
364 | 92dcb59f | Kevin Wolf | table_size * sizeof(uint64_t));
|
365 | 92dcb59f | Kevin Wolf | if (ret < 0) { |
366 | 92dcb59f | Kevin Wolf | goto fail_table;
|
367 | 92dcb59f | Kevin Wolf | } |
368 | 92dcb59f | Kevin Wolf | |
369 | 92dcb59f | Kevin Wolf | for(i = 0; i < table_size; i++) { |
370 | 87267753 | Zhi Yong Wu | be64_to_cpus(&new_table[i]); |
371 | 92dcb59f | Kevin Wolf | } |
372 | f7d0fe02 | Kevin Wolf | |
373 | 92dcb59f | Kevin Wolf | /* Hook up the new refcount table in the qcow2 header */
|
374 | 92dcb59f | Kevin Wolf | uint8_t data[12];
|
375 | f7d0fe02 | Kevin Wolf | cpu_to_be64w((uint64_t*)data, table_offset); |
376 | 92dcb59f | Kevin Wolf | cpu_to_be32w((uint32_t*)(data + 8), table_clusters);
|
377 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE); |
378 | 8b3b7206 | Kevin Wolf | ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, refcount_table_offset), |
379 | 92dcb59f | Kevin Wolf | data, sizeof(data));
|
380 | 92dcb59f | Kevin Wolf | if (ret < 0) { |
381 | 92dcb59f | Kevin Wolf | goto fail_table;
|
382 | f2b7c8b3 | Kevin Wolf | } |
383 | f2b7c8b3 | Kevin Wolf | |
384 | 92dcb59f | Kevin Wolf | /* And switch it in memory */
|
385 | 92dcb59f | Kevin Wolf | uint64_t old_table_offset = s->refcount_table_offset; |
386 | 92dcb59f | Kevin Wolf | uint64_t old_table_size = s->refcount_table_size; |
387 | 92dcb59f | Kevin Wolf | |
388 | 7267c094 | Anthony Liguori | g_free(s->refcount_table); |
389 | f7d0fe02 | Kevin Wolf | s->refcount_table = new_table; |
390 | 92dcb59f | Kevin Wolf | s->refcount_table_size = table_size; |
391 | f7d0fe02 | Kevin Wolf | s->refcount_table_offset = table_offset; |
392 | f7d0fe02 | Kevin Wolf | |
393 | 92dcb59f | Kevin Wolf | /* Free old table. Remember, we must not change free_cluster_index */
|
394 | 92dcb59f | Kevin Wolf | uint64_t old_free_cluster_index = s->free_cluster_index; |
395 | ed6ccf0f | Kevin Wolf | qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
|
396 | 92dcb59f | Kevin Wolf | s->free_cluster_index = old_free_cluster_index; |
397 | f7d0fe02 | Kevin Wolf | |
398 | 29c1a730 | Kevin Wolf | ret = load_refcount_block(bs, new_block, (void**) refcount_block);
|
399 | 92dcb59f | Kevin Wolf | if (ret < 0) { |
400 | 29c1a730 | Kevin Wolf | return ret;
|
401 | f7d0fe02 | Kevin Wolf | } |
402 | f7d0fe02 | Kevin Wolf | |
403 | 2795ecf6 | Kevin Wolf | return 0; |
404 | f7d0fe02 | Kevin Wolf | |
405 | 92dcb59f | Kevin Wolf | fail_table:
|
406 | 7267c094 | Anthony Liguori | g_free(new_table); |
407 | 92dcb59f | Kevin Wolf | fail_block:
|
408 | 29c1a730 | Kevin Wolf | if (*refcount_block != NULL) { |
409 | 29c1a730 | Kevin Wolf | qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block);
|
410 | 3b88e52b | Kevin Wolf | } |
411 | 29c1a730 | Kevin Wolf | return ret;
|
412 | 9923e05e | Kevin Wolf | } |
413 | 9923e05e | Kevin Wolf | |
414 | f7d0fe02 | Kevin Wolf | /* XXX: cache several refcount block clusters ? */
|
415 | db3a964f | Kevin Wolf | static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, |
416 | db3a964f | Kevin Wolf | int64_t offset, int64_t length, int addend)
|
417 | f7d0fe02 | Kevin Wolf | { |
418 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
419 | f7d0fe02 | Kevin Wolf | int64_t start, last, cluster_offset; |
420 | 29c1a730 | Kevin Wolf | uint16_t *refcount_block = NULL;
|
421 | 29c1a730 | Kevin Wolf | int64_t old_table_index = -1;
|
422 | 09508d13 | Kevin Wolf | int ret;
|
423 | f7d0fe02 | Kevin Wolf | |
424 | f7d0fe02 | Kevin Wolf | #ifdef DEBUG_ALLOC2
|
425 | 35ee5e39 | Frediano Ziglio | fprintf(stderr, "update_refcount: offset=%" PRId64 " size=%" PRId64 " addend=%d\n", |
426 | f7d0fe02 | Kevin Wolf | offset, length, addend); |
427 | f7d0fe02 | Kevin Wolf | #endif
|
428 | 7322afe7 | Kevin Wolf | if (length < 0) { |
429 | f7d0fe02 | Kevin Wolf | return -EINVAL;
|
430 | 7322afe7 | Kevin Wolf | } else if (length == 0) { |
431 | 7322afe7 | Kevin Wolf | return 0; |
432 | 7322afe7 | Kevin Wolf | } |
433 | 7322afe7 | Kevin Wolf | |
434 | 29c1a730 | Kevin Wolf | if (addend < 0) { |
435 | 29c1a730 | Kevin Wolf | qcow2_cache_set_dependency(bs, s->refcount_block_cache, |
436 | 29c1a730 | Kevin Wolf | s->l2_table_cache); |
437 | 29c1a730 | Kevin Wolf | } |
438 | 29c1a730 | Kevin Wolf | |
439 | f7d0fe02 | Kevin Wolf | start = offset & ~(s->cluster_size - 1);
|
440 | f7d0fe02 | Kevin Wolf | last = (offset + length - 1) & ~(s->cluster_size - 1); |
441 | f7d0fe02 | Kevin Wolf | for(cluster_offset = start; cluster_offset <= last;
|
442 | f7d0fe02 | Kevin Wolf | cluster_offset += s->cluster_size) |
443 | f7d0fe02 | Kevin Wolf | { |
444 | f7d0fe02 | Kevin Wolf | int block_index, refcount;
|
445 | f7d0fe02 | Kevin Wolf | int64_t cluster_index = cluster_offset >> s->cluster_bits; |
446 | 29c1a730 | Kevin Wolf | int64_t table_index = |
447 | 29c1a730 | Kevin Wolf | cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
448 | f7d0fe02 | Kevin Wolf | |
449 | 29c1a730 | Kevin Wolf | /* Load the refcount block and allocate it if needed */
|
450 | 29c1a730 | Kevin Wolf | if (table_index != old_table_index) {
|
451 | 29c1a730 | Kevin Wolf | if (refcount_block) {
|
452 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_put(bs, s->refcount_block_cache, |
453 | 29c1a730 | Kevin Wolf | (void**) &refcount_block);
|
454 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
455 | 29c1a730 | Kevin Wolf | goto fail;
|
456 | 29c1a730 | Kevin Wolf | } |
457 | 29c1a730 | Kevin Wolf | } |
458 | 9923e05e | Kevin Wolf | |
459 | 29c1a730 | Kevin Wolf | ret = alloc_refcount_block(bs, cluster_index, &refcount_block); |
460 | ed0df867 | Kevin Wolf | if (ret < 0) { |
461 | 29c1a730 | Kevin Wolf | goto fail;
|
462 | f7d0fe02 | Kevin Wolf | } |
463 | f7d0fe02 | Kevin Wolf | } |
464 | 29c1a730 | Kevin Wolf | old_table_index = table_index; |
465 | f7d0fe02 | Kevin Wolf | |
466 | 29c1a730 | Kevin Wolf | qcow2_cache_entry_mark_dirty(s->refcount_block_cache, refcount_block); |
467 | f7d0fe02 | Kevin Wolf | |
468 | f7d0fe02 | Kevin Wolf | /* we can update the count and save it */
|
469 | f7d0fe02 | Kevin Wolf | block_index = cluster_index & |
470 | f7d0fe02 | Kevin Wolf | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
471 | f7d0fe02 | Kevin Wolf | |
472 | 29c1a730 | Kevin Wolf | refcount = be16_to_cpu(refcount_block[block_index]); |
473 | f7d0fe02 | Kevin Wolf | refcount += addend; |
474 | 09508d13 | Kevin Wolf | if (refcount < 0 || refcount > 0xffff) { |
475 | 09508d13 | Kevin Wolf | ret = -EINVAL; |
476 | 09508d13 | Kevin Wolf | goto fail;
|
477 | 09508d13 | Kevin Wolf | } |
478 | f7d0fe02 | Kevin Wolf | if (refcount == 0 && cluster_index < s->free_cluster_index) { |
479 | f7d0fe02 | Kevin Wolf | s->free_cluster_index = cluster_index; |
480 | f7d0fe02 | Kevin Wolf | } |
481 | 29c1a730 | Kevin Wolf | refcount_block[block_index] = cpu_to_be16(refcount); |
482 | f7d0fe02 | Kevin Wolf | } |
483 | f7d0fe02 | Kevin Wolf | |
484 | 09508d13 | Kevin Wolf | ret = 0;
|
485 | 09508d13 | Kevin Wolf | fail:
|
486 | f7d0fe02 | Kevin Wolf | /* Write last changed block to disk */
|
487 | 29c1a730 | Kevin Wolf | if (refcount_block) {
|
488 | ed0df867 | Kevin Wolf | int wret;
|
489 | 29c1a730 | Kevin Wolf | wret = qcow2_cache_put(bs, s->refcount_block_cache, |
490 | 29c1a730 | Kevin Wolf | (void**) &refcount_block);
|
491 | ed0df867 | Kevin Wolf | if (wret < 0) { |
492 | ed0df867 | Kevin Wolf | return ret < 0 ? ret : wret; |
493 | f7d0fe02 | Kevin Wolf | } |
494 | f7d0fe02 | Kevin Wolf | } |
495 | f7d0fe02 | Kevin Wolf | |
496 | 09508d13 | Kevin Wolf | /*
|
497 | 09508d13 | Kevin Wolf | * Try do undo any updates if an error is returned (This may succeed in
|
498 | 09508d13 | Kevin Wolf | * some cases like ENOSPC for allocating a new refcount block)
|
499 | 09508d13 | Kevin Wolf | */
|
500 | 09508d13 | Kevin Wolf | if (ret < 0) { |
501 | 09508d13 | Kevin Wolf | int dummy;
|
502 | 09508d13 | Kevin Wolf | dummy = update_refcount(bs, offset, cluster_offset - offset, -addend); |
503 | 83e3f76c | Blue Swirl | (void)dummy;
|
504 | 09508d13 | Kevin Wolf | } |
505 | 09508d13 | Kevin Wolf | |
506 | 09508d13 | Kevin Wolf | return ret;
|
507 | f7d0fe02 | Kevin Wolf | } |
508 | f7d0fe02 | Kevin Wolf | |
509 | 018faafd | Kevin Wolf | /*
|
510 | 018faafd | Kevin Wolf | * Increases or decreases the refcount of a given cluster by one.
|
511 | 018faafd | Kevin Wolf | * addend must be 1 or -1.
|
512 | 018faafd | Kevin Wolf | *
|
513 | 018faafd | Kevin Wolf | * If the return value is non-negative, it is the new refcount of the cluster.
|
514 | 018faafd | Kevin Wolf | * If it is negative, it is -errno and indicates an error.
|
515 | 018faafd | Kevin Wolf | */
|
516 | f7d0fe02 | Kevin Wolf | static int update_cluster_refcount(BlockDriverState *bs, |
517 | f7d0fe02 | Kevin Wolf | int64_t cluster_index, |
518 | f7d0fe02 | Kevin Wolf | int addend)
|
519 | f7d0fe02 | Kevin Wolf | { |
520 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
521 | f7d0fe02 | Kevin Wolf | int ret;
|
522 | f7d0fe02 | Kevin Wolf | |
523 | f7d0fe02 | Kevin Wolf | ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend);
|
524 | f7d0fe02 | Kevin Wolf | if (ret < 0) { |
525 | f7d0fe02 | Kevin Wolf | return ret;
|
526 | f7d0fe02 | Kevin Wolf | } |
527 | f7d0fe02 | Kevin Wolf | |
528 | 1c4c2814 | Kevin Wolf | bdrv_flush(bs->file); |
529 | 1c4c2814 | Kevin Wolf | |
530 | f7d0fe02 | Kevin Wolf | return get_refcount(bs, cluster_index);
|
531 | f7d0fe02 | Kevin Wolf | } |
532 | f7d0fe02 | Kevin Wolf | |
533 | f7d0fe02 | Kevin Wolf | |
534 | f7d0fe02 | Kevin Wolf | |
535 | f7d0fe02 | Kevin Wolf | /*********************************************************/
|
536 | f7d0fe02 | Kevin Wolf | /* cluster allocation functions */
|
537 | f7d0fe02 | Kevin Wolf | |
538 | f7d0fe02 | Kevin Wolf | |
539 | f7d0fe02 | Kevin Wolf | |
540 | f7d0fe02 | Kevin Wolf | /* return < 0 if error */
|
541 | f7d0fe02 | Kevin Wolf | static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
|
542 | f7d0fe02 | Kevin Wolf | { |
543 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
544 | 2eaa8f63 | Kevin Wolf | int i, nb_clusters, refcount;
|
545 | f7d0fe02 | Kevin Wolf | |
546 | f7d0fe02 | Kevin Wolf | nb_clusters = size_to_clusters(s, size); |
547 | f7d0fe02 | Kevin Wolf | retry:
|
548 | f7d0fe02 | Kevin Wolf | for(i = 0; i < nb_clusters; i++) { |
549 | 508e0893 | Stefan Hajnoczi | int64_t next_cluster_index = s->free_cluster_index++; |
550 | 2eaa8f63 | Kevin Wolf | refcount = get_refcount(bs, next_cluster_index); |
551 | 2eaa8f63 | Kevin Wolf | |
552 | 2eaa8f63 | Kevin Wolf | if (refcount < 0) { |
553 | 2eaa8f63 | Kevin Wolf | return refcount;
|
554 | 2eaa8f63 | Kevin Wolf | } else if (refcount != 0) { |
555 | f7d0fe02 | Kevin Wolf | goto retry;
|
556 | 2eaa8f63 | Kevin Wolf | } |
557 | f7d0fe02 | Kevin Wolf | } |
558 | f7d0fe02 | Kevin Wolf | #ifdef DEBUG_ALLOC2
|
559 | 35ee5e39 | Frediano Ziglio | fprintf(stderr, "alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n", |
560 | f7d0fe02 | Kevin Wolf | size, |
561 | f7d0fe02 | Kevin Wolf | (s->free_cluster_index - nb_clusters) << s->cluster_bits); |
562 | f7d0fe02 | Kevin Wolf | #endif
|
563 | f7d0fe02 | Kevin Wolf | return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
|
564 | f7d0fe02 | Kevin Wolf | } |
565 | f7d0fe02 | Kevin Wolf | |
566 | ed6ccf0f | Kevin Wolf | int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size) |
567 | f7d0fe02 | Kevin Wolf | { |
568 | f7d0fe02 | Kevin Wolf | int64_t offset; |
569 | db3a964f | Kevin Wolf | int ret;
|
570 | f7d0fe02 | Kevin Wolf | |
571 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC); |
572 | f7d0fe02 | Kevin Wolf | offset = alloc_clusters_noref(bs, size); |
573 | 2eaa8f63 | Kevin Wolf | if (offset < 0) { |
574 | 2eaa8f63 | Kevin Wolf | return offset;
|
575 | 2eaa8f63 | Kevin Wolf | } |
576 | 2eaa8f63 | Kevin Wolf | |
577 | db3a964f | Kevin Wolf | ret = update_refcount(bs, offset, size, 1);
|
578 | db3a964f | Kevin Wolf | if (ret < 0) { |
579 | db3a964f | Kevin Wolf | return ret;
|
580 | db3a964f | Kevin Wolf | } |
581 | 1c4c2814 | Kevin Wolf | |
582 | f7d0fe02 | Kevin Wolf | return offset;
|
583 | f7d0fe02 | Kevin Wolf | } |
584 | f7d0fe02 | Kevin Wolf | |
585 | 256900b1 | Kevin Wolf | int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
|
586 | 256900b1 | Kevin Wolf | int nb_clusters)
|
587 | 256900b1 | Kevin Wolf | { |
588 | 256900b1 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
589 | 256900b1 | Kevin Wolf | uint64_t cluster_index; |
590 | f24423bd | Kevin Wolf | uint64_t old_free_cluster_index; |
591 | 256900b1 | Kevin Wolf | int i, refcount, ret;
|
592 | 256900b1 | Kevin Wolf | |
593 | 256900b1 | Kevin Wolf | /* Check how many clusters there are free */
|
594 | 256900b1 | Kevin Wolf | cluster_index = offset >> s->cluster_bits; |
595 | 256900b1 | Kevin Wolf | for(i = 0; i < nb_clusters; i++) { |
596 | 256900b1 | Kevin Wolf | refcount = get_refcount(bs, cluster_index++); |
597 | 256900b1 | Kevin Wolf | |
598 | 256900b1 | Kevin Wolf | if (refcount < 0) { |
599 | 256900b1 | Kevin Wolf | return refcount;
|
600 | 256900b1 | Kevin Wolf | } else if (refcount != 0) { |
601 | 256900b1 | Kevin Wolf | break;
|
602 | 256900b1 | Kevin Wolf | } |
603 | 256900b1 | Kevin Wolf | } |
604 | 256900b1 | Kevin Wolf | |
605 | 256900b1 | Kevin Wolf | /* And then allocate them */
|
606 | f24423bd | Kevin Wolf | old_free_cluster_index = s->free_cluster_index; |
607 | f24423bd | Kevin Wolf | s->free_cluster_index = cluster_index + i; |
608 | f24423bd | Kevin Wolf | |
609 | 256900b1 | Kevin Wolf | ret = update_refcount(bs, offset, i << s->cluster_bits, 1);
|
610 | 256900b1 | Kevin Wolf | if (ret < 0) { |
611 | 256900b1 | Kevin Wolf | return ret;
|
612 | 256900b1 | Kevin Wolf | } |
613 | 256900b1 | Kevin Wolf | |
614 | f24423bd | Kevin Wolf | s->free_cluster_index = old_free_cluster_index; |
615 | f24423bd | Kevin Wolf | |
616 | 256900b1 | Kevin Wolf | return i;
|
617 | 256900b1 | Kevin Wolf | } |
618 | 256900b1 | Kevin Wolf | |
619 | f7d0fe02 | Kevin Wolf | /* only used to allocate compressed sectors. We try to allocate
|
620 | f7d0fe02 | Kevin Wolf | contiguous sectors. size must be <= cluster_size */
|
621 | ed6ccf0f | Kevin Wolf | int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
|
622 | f7d0fe02 | Kevin Wolf | { |
623 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
624 | f7d0fe02 | Kevin Wolf | int64_t offset, cluster_offset; |
625 | f7d0fe02 | Kevin Wolf | int free_in_cluster;
|
626 | f7d0fe02 | Kevin Wolf | |
627 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC_BYTES); |
628 | f7d0fe02 | Kevin Wolf | assert(size > 0 && size <= s->cluster_size);
|
629 | f7d0fe02 | Kevin Wolf | if (s->free_byte_offset == 0) { |
630 | 206e6d85 | Stefan Hajnoczi | offset = qcow2_alloc_clusters(bs, s->cluster_size); |
631 | 206e6d85 | Stefan Hajnoczi | if (offset < 0) { |
632 | 206e6d85 | Stefan Hajnoczi | return offset;
|
633 | 5d757b56 | Kevin Wolf | } |
634 | 206e6d85 | Stefan Hajnoczi | s->free_byte_offset = offset; |
635 | f7d0fe02 | Kevin Wolf | } |
636 | f7d0fe02 | Kevin Wolf | redo:
|
637 | f7d0fe02 | Kevin Wolf | free_in_cluster = s->cluster_size - |
638 | f7d0fe02 | Kevin Wolf | (s->free_byte_offset & (s->cluster_size - 1));
|
639 | f7d0fe02 | Kevin Wolf | if (size <= free_in_cluster) {
|
640 | f7d0fe02 | Kevin Wolf | /* enough space in current cluster */
|
641 | f7d0fe02 | Kevin Wolf | offset = s->free_byte_offset; |
642 | f7d0fe02 | Kevin Wolf | s->free_byte_offset += size; |
643 | f7d0fe02 | Kevin Wolf | free_in_cluster -= size; |
644 | f7d0fe02 | Kevin Wolf | if (free_in_cluster == 0) |
645 | f7d0fe02 | Kevin Wolf | s->free_byte_offset = 0;
|
646 | f7d0fe02 | Kevin Wolf | if ((offset & (s->cluster_size - 1)) != 0) |
647 | f7d0fe02 | Kevin Wolf | update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
648 | f7d0fe02 | Kevin Wolf | } else {
|
649 | ed6ccf0f | Kevin Wolf | offset = qcow2_alloc_clusters(bs, s->cluster_size); |
650 | 5d757b56 | Kevin Wolf | if (offset < 0) { |
651 | 5d757b56 | Kevin Wolf | return offset;
|
652 | 5d757b56 | Kevin Wolf | } |
653 | f7d0fe02 | Kevin Wolf | cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
|
654 | f7d0fe02 | Kevin Wolf | if ((cluster_offset + s->cluster_size) == offset) {
|
655 | f7d0fe02 | Kevin Wolf | /* we are lucky: contiguous data */
|
656 | f7d0fe02 | Kevin Wolf | offset = s->free_byte_offset; |
657 | f7d0fe02 | Kevin Wolf | update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
658 | f7d0fe02 | Kevin Wolf | s->free_byte_offset += size; |
659 | f7d0fe02 | Kevin Wolf | } else {
|
660 | f7d0fe02 | Kevin Wolf | s->free_byte_offset = offset; |
661 | f7d0fe02 | Kevin Wolf | goto redo;
|
662 | f7d0fe02 | Kevin Wolf | } |
663 | f7d0fe02 | Kevin Wolf | } |
664 | 29216ed1 | Kevin Wolf | |
665 | 29216ed1 | Kevin Wolf | bdrv_flush(bs->file); |
666 | f7d0fe02 | Kevin Wolf | return offset;
|
667 | f7d0fe02 | Kevin Wolf | } |
668 | f7d0fe02 | Kevin Wolf | |
669 | ed6ccf0f | Kevin Wolf | void qcow2_free_clusters(BlockDriverState *bs,
|
670 | f7d0fe02 | Kevin Wolf | int64_t offset, int64_t size) |
671 | f7d0fe02 | Kevin Wolf | { |
672 | db3a964f | Kevin Wolf | int ret;
|
673 | db3a964f | Kevin Wolf | |
674 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_FREE); |
675 | db3a964f | Kevin Wolf | ret = update_refcount(bs, offset, size, -1);
|
676 | db3a964f | Kevin Wolf | if (ret < 0) { |
677 | db3a964f | Kevin Wolf | fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
|
678 | 003fad6e | Kevin Wolf | /* TODO Remember the clusters to free them later and avoid leaking */
|
679 | db3a964f | Kevin Wolf | } |
680 | f7d0fe02 | Kevin Wolf | } |
681 | f7d0fe02 | Kevin Wolf | |
682 | 45aba42f | Kevin Wolf | /*
|
683 | c7a4c37a | Kevin Wolf | * Free a cluster using its L2 entry (handles clusters of all types, e.g.
|
684 | c7a4c37a | Kevin Wolf | * normal cluster, compressed cluster, etc.)
|
685 | 45aba42f | Kevin Wolf | */
|
686 | ed6ccf0f | Kevin Wolf | void qcow2_free_any_clusters(BlockDriverState *bs,
|
687 | c7a4c37a | Kevin Wolf | uint64_t l2_entry, int nb_clusters)
|
688 | 45aba42f | Kevin Wolf | { |
689 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
690 | 45aba42f | Kevin Wolf | |
691 | c7a4c37a | Kevin Wolf | switch (qcow2_get_cluster_type(l2_entry)) {
|
692 | c7a4c37a | Kevin Wolf | case QCOW2_CLUSTER_COMPRESSED:
|
693 | c7a4c37a | Kevin Wolf | { |
694 | c7a4c37a | Kevin Wolf | int nb_csectors;
|
695 | c7a4c37a | Kevin Wolf | nb_csectors = ((l2_entry >> s->csize_shift) & |
696 | c7a4c37a | Kevin Wolf | s->csize_mask) + 1;
|
697 | c7a4c37a | Kevin Wolf | qcow2_free_clusters(bs, |
698 | c7a4c37a | Kevin Wolf | (l2_entry & s->cluster_offset_mask) & ~511,
|
699 | c7a4c37a | Kevin Wolf | nb_csectors * 512);
|
700 | c7a4c37a | Kevin Wolf | } |
701 | c7a4c37a | Kevin Wolf | break;
|
702 | c7a4c37a | Kevin Wolf | case QCOW2_CLUSTER_NORMAL:
|
703 | c7a4c37a | Kevin Wolf | qcow2_free_clusters(bs, l2_entry & L2E_OFFSET_MASK, |
704 | c7a4c37a | Kevin Wolf | nb_clusters << s->cluster_bits); |
705 | c7a4c37a | Kevin Wolf | break;
|
706 | c7a4c37a | Kevin Wolf | case QCOW2_CLUSTER_UNALLOCATED:
|
707 | 6377af48 | Kevin Wolf | case QCOW2_CLUSTER_ZERO:
|
708 | c7a4c37a | Kevin Wolf | break;
|
709 | c7a4c37a | Kevin Wolf | default:
|
710 | c7a4c37a | Kevin Wolf | abort(); |
711 | 45aba42f | Kevin Wolf | } |
712 | 45aba42f | Kevin Wolf | } |
713 | 45aba42f | Kevin Wolf | |
714 | f7d0fe02 | Kevin Wolf | |
715 | f7d0fe02 | Kevin Wolf | |
716 | f7d0fe02 | Kevin Wolf | /*********************************************************/
|
717 | f7d0fe02 | Kevin Wolf | /* snapshots and image creation */
|
718 | f7d0fe02 | Kevin Wolf | |
719 | f7d0fe02 | Kevin Wolf | |
720 | f7d0fe02 | Kevin Wolf | |
721 | f7d0fe02 | Kevin Wolf | /* update the refcounts of snapshots and the copied flag */
|
722 | ed6ccf0f | Kevin Wolf | int qcow2_update_snapshot_refcount(BlockDriverState *bs,
|
723 | ed6ccf0f | Kevin Wolf | int64_t l1_table_offset, int l1_size, int addend) |
724 | f7d0fe02 | Kevin Wolf | { |
725 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
726 | f7d0fe02 | Kevin Wolf | uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated; |
727 | f7d0fe02 | Kevin Wolf | int64_t old_offset, old_l2_offset; |
728 | 93913dfd | Kevin Wolf | int i, j, l1_modified = 0, nb_csectors, refcount; |
729 | 29c1a730 | Kevin Wolf | int ret;
|
730 | f7d0fe02 | Kevin Wolf | |
731 | f7d0fe02 | Kevin Wolf | l2_table = NULL;
|
732 | f7d0fe02 | Kevin Wolf | l1_table = NULL;
|
733 | f7d0fe02 | Kevin Wolf | l1_size2 = l1_size * sizeof(uint64_t);
|
734 | 43a0cac4 | Kevin Wolf | |
735 | 43a0cac4 | Kevin Wolf | /* WARNING: qcow2_snapshot_goto relies on this function not using the
|
736 | 43a0cac4 | Kevin Wolf | * l1_table_offset when it is the current s->l1_table_offset! Be careful
|
737 | 43a0cac4 | Kevin Wolf | * when changing this! */
|
738 | f7d0fe02 | Kevin Wolf | if (l1_table_offset != s->l1_table_offset) {
|
739 | 702ef63f | Kevin Wolf | if (l1_size2 != 0) { |
740 | 7267c094 | Anthony Liguori | l1_table = g_malloc0(align_offset(l1_size2, 512));
|
741 | 702ef63f | Kevin Wolf | } else {
|
742 | 702ef63f | Kevin Wolf | l1_table = NULL;
|
743 | 702ef63f | Kevin Wolf | } |
744 | f7d0fe02 | Kevin Wolf | l1_allocated = 1;
|
745 | 66f82cee | Kevin Wolf | if (bdrv_pread(bs->file, l1_table_offset,
|
746 | f7d0fe02 | Kevin Wolf | l1_table, l1_size2) != l1_size2) |
747 | 93913dfd | Kevin Wolf | { |
748 | 93913dfd | Kevin Wolf | ret = -EIO; |
749 | f7d0fe02 | Kevin Wolf | goto fail;
|
750 | 93913dfd | Kevin Wolf | } |
751 | 93913dfd | Kevin Wolf | |
752 | f7d0fe02 | Kevin Wolf | for(i = 0;i < l1_size; i++) |
753 | f7d0fe02 | Kevin Wolf | be64_to_cpus(&l1_table[i]); |
754 | f7d0fe02 | Kevin Wolf | } else {
|
755 | f7d0fe02 | Kevin Wolf | assert(l1_size == s->l1_size); |
756 | f7d0fe02 | Kevin Wolf | l1_table = s->l1_table; |
757 | f7d0fe02 | Kevin Wolf | l1_allocated = 0;
|
758 | f7d0fe02 | Kevin Wolf | } |
759 | f7d0fe02 | Kevin Wolf | |
760 | f7d0fe02 | Kevin Wolf | for(i = 0; i < l1_size; i++) { |
761 | f7d0fe02 | Kevin Wolf | l2_offset = l1_table[i]; |
762 | f7d0fe02 | Kevin Wolf | if (l2_offset) {
|
763 | f7d0fe02 | Kevin Wolf | old_l2_offset = l2_offset; |
764 | 8e37f681 | Kevin Wolf | l2_offset &= L1E_OFFSET_MASK; |
765 | 29c1a730 | Kevin Wolf | |
766 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_get(bs, s->l2_table_cache, l2_offset, |
767 | 29c1a730 | Kevin Wolf | (void**) &l2_table);
|
768 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
769 | f7d0fe02 | Kevin Wolf | goto fail;
|
770 | 29c1a730 | Kevin Wolf | } |
771 | 29c1a730 | Kevin Wolf | |
772 | f7d0fe02 | Kevin Wolf | for(j = 0; j < s->l2_size; j++) { |
773 | f7d0fe02 | Kevin Wolf | offset = be64_to_cpu(l2_table[j]); |
774 | f7d0fe02 | Kevin Wolf | if (offset != 0) { |
775 | f7d0fe02 | Kevin Wolf | old_offset = offset; |
776 | f7d0fe02 | Kevin Wolf | offset &= ~QCOW_OFLAG_COPIED; |
777 | f7d0fe02 | Kevin Wolf | if (offset & QCOW_OFLAG_COMPRESSED) {
|
778 | f7d0fe02 | Kevin Wolf | nb_csectors = ((offset >> s->csize_shift) & |
779 | f7d0fe02 | Kevin Wolf | s->csize_mask) + 1;
|
780 | db3a964f | Kevin Wolf | if (addend != 0) { |
781 | db3a964f | Kevin Wolf | int ret;
|
782 | db3a964f | Kevin Wolf | ret = update_refcount(bs, |
783 | db3a964f | Kevin Wolf | (offset & s->cluster_offset_mask) & ~511,
|
784 | db3a964f | Kevin Wolf | nb_csectors * 512, addend);
|
785 | db3a964f | Kevin Wolf | if (ret < 0) { |
786 | db3a964f | Kevin Wolf | goto fail;
|
787 | db3a964f | Kevin Wolf | } |
788 | 1c4c2814 | Kevin Wolf | |
789 | 1c4c2814 | Kevin Wolf | /* TODO Flushing once for the whole function should
|
790 | 1c4c2814 | Kevin Wolf | * be enough */
|
791 | 1c4c2814 | Kevin Wolf | bdrv_flush(bs->file); |
792 | db3a964f | Kevin Wolf | } |
793 | f7d0fe02 | Kevin Wolf | /* compressed clusters are never modified */
|
794 | f7d0fe02 | Kevin Wolf | refcount = 2;
|
795 | f7d0fe02 | Kevin Wolf | } else {
|
796 | 8e37f681 | Kevin Wolf | uint64_t cluster_index = (offset & L2E_OFFSET_MASK) >> s->cluster_bits; |
797 | f7d0fe02 | Kevin Wolf | if (addend != 0) { |
798 | 8e37f681 | Kevin Wolf | refcount = update_cluster_refcount(bs, cluster_index, addend); |
799 | f7d0fe02 | Kevin Wolf | } else {
|
800 | 8e37f681 | Kevin Wolf | refcount = get_refcount(bs, cluster_index); |
801 | f7d0fe02 | Kevin Wolf | } |
802 | 018faafd | Kevin Wolf | |
803 | 018faafd | Kevin Wolf | if (refcount < 0) { |
804 | 93913dfd | Kevin Wolf | ret = -EIO; |
805 | 018faafd | Kevin Wolf | goto fail;
|
806 | 018faafd | Kevin Wolf | } |
807 | f7d0fe02 | Kevin Wolf | } |
808 | f7d0fe02 | Kevin Wolf | |
809 | f7d0fe02 | Kevin Wolf | if (refcount == 1) { |
810 | f7d0fe02 | Kevin Wolf | offset |= QCOW_OFLAG_COPIED; |
811 | f7d0fe02 | Kevin Wolf | } |
812 | f7d0fe02 | Kevin Wolf | if (offset != old_offset) {
|
813 | 29c1a730 | Kevin Wolf | if (addend > 0) { |
814 | 29c1a730 | Kevin Wolf | qcow2_cache_set_dependency(bs, s->l2_table_cache, |
815 | 29c1a730 | Kevin Wolf | s->refcount_block_cache); |
816 | 29c1a730 | Kevin Wolf | } |
817 | f7d0fe02 | Kevin Wolf | l2_table[j] = cpu_to_be64(offset); |
818 | 29c1a730 | Kevin Wolf | qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table); |
819 | f7d0fe02 | Kevin Wolf | } |
820 | f7d0fe02 | Kevin Wolf | } |
821 | f7d0fe02 | Kevin Wolf | } |
822 | 29c1a730 | Kevin Wolf | |
823 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
824 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
825 | 29c1a730 | Kevin Wolf | goto fail;
|
826 | f7d0fe02 | Kevin Wolf | } |
827 | f7d0fe02 | Kevin Wolf | |
828 | 29c1a730 | Kevin Wolf | |
829 | f7d0fe02 | Kevin Wolf | if (addend != 0) { |
830 | f7d0fe02 | Kevin Wolf | refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend); |
831 | f7d0fe02 | Kevin Wolf | } else {
|
832 | f7d0fe02 | Kevin Wolf | refcount = get_refcount(bs, l2_offset >> s->cluster_bits); |
833 | f7d0fe02 | Kevin Wolf | } |
834 | 018faafd | Kevin Wolf | if (refcount < 0) { |
835 | 93913dfd | Kevin Wolf | ret = -EIO; |
836 | 018faafd | Kevin Wolf | goto fail;
|
837 | 018faafd | Kevin Wolf | } else if (refcount == 1) { |
838 | f7d0fe02 | Kevin Wolf | l2_offset |= QCOW_OFLAG_COPIED; |
839 | f7d0fe02 | Kevin Wolf | } |
840 | f7d0fe02 | Kevin Wolf | if (l2_offset != old_l2_offset) {
|
841 | f7d0fe02 | Kevin Wolf | l1_table[i] = l2_offset; |
842 | f7d0fe02 | Kevin Wolf | l1_modified = 1;
|
843 | f7d0fe02 | Kevin Wolf | } |
844 | f7d0fe02 | Kevin Wolf | } |
845 | f7d0fe02 | Kevin Wolf | } |
846 | 93913dfd | Kevin Wolf | |
847 | 93913dfd | Kevin Wolf | ret = 0;
|
848 | 93913dfd | Kevin Wolf | fail:
|
849 | 93913dfd | Kevin Wolf | if (l2_table) {
|
850 | 93913dfd | Kevin Wolf | qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
851 | 93913dfd | Kevin Wolf | } |
852 | 93913dfd | Kevin Wolf | |
853 | 43a0cac4 | Kevin Wolf | /* Update L1 only if it isn't deleted anyway (addend = -1) */
|
854 | 43a0cac4 | Kevin Wolf | if (addend >= 0 && l1_modified) { |
855 | f7d0fe02 | Kevin Wolf | for(i = 0; i < l1_size; i++) |
856 | f7d0fe02 | Kevin Wolf | cpu_to_be64s(&l1_table[i]); |
857 | 8b3b7206 | Kevin Wolf | if (bdrv_pwrite_sync(bs->file, l1_table_offset, l1_table,
|
858 | 8b3b7206 | Kevin Wolf | l1_size2) < 0)
|
859 | f7d0fe02 | Kevin Wolf | goto fail;
|
860 | f7d0fe02 | Kevin Wolf | for(i = 0; i < l1_size; i++) |
861 | f7d0fe02 | Kevin Wolf | be64_to_cpus(&l1_table[i]); |
862 | f7d0fe02 | Kevin Wolf | } |
863 | f7d0fe02 | Kevin Wolf | if (l1_allocated)
|
864 | 7267c094 | Anthony Liguori | g_free(l1_table); |
865 | 93913dfd | Kevin Wolf | return ret;
|
866 | f7d0fe02 | Kevin Wolf | } |
867 | f7d0fe02 | Kevin Wolf | |
868 | f7d0fe02 | Kevin Wolf | |
869 | f7d0fe02 | Kevin Wolf | |
870 | f7d0fe02 | Kevin Wolf | |
871 | f7d0fe02 | Kevin Wolf | /*********************************************************/
|
872 | f7d0fe02 | Kevin Wolf | /* refcount checking functions */
|
873 | f7d0fe02 | Kevin Wolf | |
874 | f7d0fe02 | Kevin Wolf | |
875 | f7d0fe02 | Kevin Wolf | |
876 | f7d0fe02 | Kevin Wolf | /*
|
877 | f7d0fe02 | Kevin Wolf | * Increases the refcount for a range of clusters in a given refcount table.
|
878 | f7d0fe02 | Kevin Wolf | * This is used to construct a temporary refcount table out of L1 and L2 tables
|
879 | f7d0fe02 | Kevin Wolf | * which can be compared the the refcount table saved in the image.
|
880 | f7d0fe02 | Kevin Wolf | *
|
881 | 9ac228e0 | Kevin Wolf | * Modifies the number of errors in res.
|
882 | f7d0fe02 | Kevin Wolf | */
|
883 | 9ac228e0 | Kevin Wolf | static void inc_refcounts(BlockDriverState *bs, |
884 | 9ac228e0 | Kevin Wolf | BdrvCheckResult *res, |
885 | f7d0fe02 | Kevin Wolf | uint16_t *refcount_table, |
886 | f7d0fe02 | Kevin Wolf | int refcount_table_size,
|
887 | f7d0fe02 | Kevin Wolf | int64_t offset, int64_t size) |
888 | f7d0fe02 | Kevin Wolf | { |
889 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
890 | f7d0fe02 | Kevin Wolf | int64_t start, last, cluster_offset; |
891 | f7d0fe02 | Kevin Wolf | int k;
|
892 | f7d0fe02 | Kevin Wolf | |
893 | f7d0fe02 | Kevin Wolf | if (size <= 0) |
894 | 9ac228e0 | Kevin Wolf | return;
|
895 | f7d0fe02 | Kevin Wolf | |
896 | f7d0fe02 | Kevin Wolf | start = offset & ~(s->cluster_size - 1);
|
897 | f7d0fe02 | Kevin Wolf | last = (offset + size - 1) & ~(s->cluster_size - 1); |
898 | f7d0fe02 | Kevin Wolf | for(cluster_offset = start; cluster_offset <= last;
|
899 | f7d0fe02 | Kevin Wolf | cluster_offset += s->cluster_size) { |
900 | f7d0fe02 | Kevin Wolf | k = cluster_offset >> s->cluster_bits; |
901 | 9ac228e0 | Kevin Wolf | if (k < 0) { |
902 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n", |
903 | f7d0fe02 | Kevin Wolf | cluster_offset); |
904 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
905 | 9ac228e0 | Kevin Wolf | } else if (k >= refcount_table_size) { |
906 | 9ac228e0 | Kevin Wolf | fprintf(stderr, "Warning: cluster offset=0x%" PRIx64 " is after " |
907 | 9ac228e0 | Kevin Wolf | "the end of the image file, can't properly check refcounts.\n",
|
908 | 9ac228e0 | Kevin Wolf | cluster_offset); |
909 | 9ac228e0 | Kevin Wolf | res->check_errors++; |
910 | f7d0fe02 | Kevin Wolf | } else {
|
911 | f7d0fe02 | Kevin Wolf | if (++refcount_table[k] == 0) { |
912 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
|
913 | f7d0fe02 | Kevin Wolf | "\n", cluster_offset);
|
914 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
915 | f7d0fe02 | Kevin Wolf | } |
916 | f7d0fe02 | Kevin Wolf | } |
917 | f7d0fe02 | Kevin Wolf | } |
918 | f7d0fe02 | Kevin Wolf | } |
919 | f7d0fe02 | Kevin Wolf | |
920 | f7d0fe02 | Kevin Wolf | /*
|
921 | f7d0fe02 | Kevin Wolf | * Increases the refcount in the given refcount table for the all clusters
|
922 | f7d0fe02 | Kevin Wolf | * referenced in the L2 table. While doing so, performs some checks on L2
|
923 | f7d0fe02 | Kevin Wolf | * entries.
|
924 | f7d0fe02 | Kevin Wolf | *
|
925 | f7d0fe02 | Kevin Wolf | * Returns the number of errors found by the checks or -errno if an internal
|
926 | f7d0fe02 | Kevin Wolf | * error occurred.
|
927 | f7d0fe02 | Kevin Wolf | */
|
928 | 9ac228e0 | Kevin Wolf | static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res, |
929 | f7d0fe02 | Kevin Wolf | uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
|
930 | f7d0fe02 | Kevin Wolf | int check_copied)
|
931 | f7d0fe02 | Kevin Wolf | { |
932 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
933 | afdf0abe | Kevin Wolf | uint64_t *l2_table, l2_entry; |
934 | f7d0fe02 | Kevin Wolf | int i, l2_size, nb_csectors, refcount;
|
935 | f7d0fe02 | Kevin Wolf | |
936 | f7d0fe02 | Kevin Wolf | /* Read L2 table from disk */
|
937 | f7d0fe02 | Kevin Wolf | l2_size = s->l2_size * sizeof(uint64_t);
|
938 | 7267c094 | Anthony Liguori | l2_table = g_malloc(l2_size); |
939 | f7d0fe02 | Kevin Wolf | |
940 | 66f82cee | Kevin Wolf | if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
|
941 | f7d0fe02 | Kevin Wolf | goto fail;
|
942 | f7d0fe02 | Kevin Wolf | |
943 | f7d0fe02 | Kevin Wolf | /* Do the actual checks */
|
944 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->l2_size; i++) { |
945 | afdf0abe | Kevin Wolf | l2_entry = be64_to_cpu(l2_table[i]); |
946 | afdf0abe | Kevin Wolf | |
947 | afdf0abe | Kevin Wolf | switch (qcow2_get_cluster_type(l2_entry)) {
|
948 | afdf0abe | Kevin Wolf | case QCOW2_CLUSTER_COMPRESSED:
|
949 | afdf0abe | Kevin Wolf | /* Compressed clusters don't have QCOW_OFLAG_COPIED */
|
950 | afdf0abe | Kevin Wolf | if (l2_entry & QCOW_OFLAG_COPIED) {
|
951 | afdf0abe | Kevin Wolf | fprintf(stderr, "ERROR: cluster %" PRId64 ": " |
952 | afdf0abe | Kevin Wolf | "copied flag must never be set for compressed "
|
953 | afdf0abe | Kevin Wolf | "clusters\n", l2_entry >> s->cluster_bits);
|
954 | afdf0abe | Kevin Wolf | l2_entry &= ~QCOW_OFLAG_COPIED; |
955 | afdf0abe | Kevin Wolf | res->corruptions++; |
956 | afdf0abe | Kevin Wolf | } |
957 | f7d0fe02 | Kevin Wolf | |
958 | afdf0abe | Kevin Wolf | /* Mark cluster as used */
|
959 | afdf0abe | Kevin Wolf | nb_csectors = ((l2_entry >> s->csize_shift) & |
960 | afdf0abe | Kevin Wolf | s->csize_mask) + 1;
|
961 | afdf0abe | Kevin Wolf | l2_entry &= s->cluster_offset_mask; |
962 | afdf0abe | Kevin Wolf | inc_refcounts(bs, res, refcount_table, refcount_table_size, |
963 | afdf0abe | Kevin Wolf | l2_entry & ~511, nb_csectors * 512); |
964 | afdf0abe | Kevin Wolf | break;
|
965 | f7d0fe02 | Kevin Wolf | |
966 | 6377af48 | Kevin Wolf | case QCOW2_CLUSTER_ZERO:
|
967 | 6377af48 | Kevin Wolf | if ((l2_entry & L2E_OFFSET_MASK) == 0) { |
968 | 6377af48 | Kevin Wolf | break;
|
969 | 6377af48 | Kevin Wolf | } |
970 | 6377af48 | Kevin Wolf | /* fall through */
|
971 | 6377af48 | Kevin Wolf | |
972 | afdf0abe | Kevin Wolf | case QCOW2_CLUSTER_NORMAL:
|
973 | afdf0abe | Kevin Wolf | { |
974 | afdf0abe | Kevin Wolf | /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
|
975 | afdf0abe | Kevin Wolf | uint64_t offset = l2_entry & L2E_OFFSET_MASK; |
976 | f7d0fe02 | Kevin Wolf | |
977 | afdf0abe | Kevin Wolf | if (check_copied) {
|
978 | afdf0abe | Kevin Wolf | refcount = get_refcount(bs, offset >> s->cluster_bits); |
979 | afdf0abe | Kevin Wolf | if (refcount < 0) { |
980 | afdf0abe | Kevin Wolf | fprintf(stderr, "Can't get refcount for offset %"
|
981 | afdf0abe | Kevin Wolf | PRIx64 ": %s\n", l2_entry, strerror(-refcount));
|
982 | afdf0abe | Kevin Wolf | goto fail;
|
983 | afdf0abe | Kevin Wolf | } |
984 | afdf0abe | Kevin Wolf | if ((refcount == 1) != ((l2_entry & QCOW_OFLAG_COPIED) != 0)) { |
985 | afdf0abe | Kevin Wolf | fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
|
986 | afdf0abe | Kevin Wolf | PRIx64 " refcount=%d\n", l2_entry, refcount);
|
987 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
988 | f7d0fe02 | Kevin Wolf | } |
989 | f7d0fe02 | Kevin Wolf | } |
990 | afdf0abe | Kevin Wolf | |
991 | afdf0abe | Kevin Wolf | /* Mark cluster as used */
|
992 | afdf0abe | Kevin Wolf | inc_refcounts(bs, res, refcount_table,refcount_table_size, |
993 | afdf0abe | Kevin Wolf | offset, s->cluster_size); |
994 | afdf0abe | Kevin Wolf | |
995 | afdf0abe | Kevin Wolf | /* Correct offsets are cluster aligned */
|
996 | afdf0abe | Kevin Wolf | if (offset & (s->cluster_size - 1)) { |
997 | afdf0abe | Kevin Wolf | fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not " |
998 | afdf0abe | Kevin Wolf | "properly aligned; L2 entry corrupted.\n", offset);
|
999 | afdf0abe | Kevin Wolf | res->corruptions++; |
1000 | afdf0abe | Kevin Wolf | } |
1001 | afdf0abe | Kevin Wolf | break;
|
1002 | afdf0abe | Kevin Wolf | } |
1003 | afdf0abe | Kevin Wolf | |
1004 | afdf0abe | Kevin Wolf | case QCOW2_CLUSTER_UNALLOCATED:
|
1005 | afdf0abe | Kevin Wolf | break;
|
1006 | afdf0abe | Kevin Wolf | |
1007 | afdf0abe | Kevin Wolf | default:
|
1008 | afdf0abe | Kevin Wolf | abort(); |
1009 | f7d0fe02 | Kevin Wolf | } |
1010 | f7d0fe02 | Kevin Wolf | } |
1011 | f7d0fe02 | Kevin Wolf | |
1012 | 7267c094 | Anthony Liguori | g_free(l2_table); |
1013 | 9ac228e0 | Kevin Wolf | return 0; |
1014 | f7d0fe02 | Kevin Wolf | |
1015 | f7d0fe02 | Kevin Wolf | fail:
|
1016 | 9ac228e0 | Kevin Wolf | fprintf(stderr, "ERROR: I/O error in check_refcounts_l2\n");
|
1017 | 7267c094 | Anthony Liguori | g_free(l2_table); |
1018 | f7d0fe02 | Kevin Wolf | return -EIO;
|
1019 | f7d0fe02 | Kevin Wolf | } |
1020 | f7d0fe02 | Kevin Wolf | |
1021 | f7d0fe02 | Kevin Wolf | /*
|
1022 | f7d0fe02 | Kevin Wolf | * Increases the refcount for the L1 table, its L2 tables and all referenced
|
1023 | f7d0fe02 | Kevin Wolf | * clusters in the given refcount table. While doing so, performs some checks
|
1024 | f7d0fe02 | Kevin Wolf | * on L1 and L2 entries.
|
1025 | f7d0fe02 | Kevin Wolf | *
|
1026 | f7d0fe02 | Kevin Wolf | * Returns the number of errors found by the checks or -errno if an internal
|
1027 | f7d0fe02 | Kevin Wolf | * error occurred.
|
1028 | f7d0fe02 | Kevin Wolf | */
|
1029 | f7d0fe02 | Kevin Wolf | static int check_refcounts_l1(BlockDriverState *bs, |
1030 | 9ac228e0 | Kevin Wolf | BdrvCheckResult *res, |
1031 | f7d0fe02 | Kevin Wolf | uint16_t *refcount_table, |
1032 | f7d0fe02 | Kevin Wolf | int refcount_table_size,
|
1033 | f7d0fe02 | Kevin Wolf | int64_t l1_table_offset, int l1_size,
|
1034 | f7d0fe02 | Kevin Wolf | int check_copied)
|
1035 | f7d0fe02 | Kevin Wolf | { |
1036 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
1037 | f7d0fe02 | Kevin Wolf | uint64_t *l1_table, l2_offset, l1_size2; |
1038 | f7d0fe02 | Kevin Wolf | int i, refcount, ret;
|
1039 | f7d0fe02 | Kevin Wolf | |
1040 | f7d0fe02 | Kevin Wolf | l1_size2 = l1_size * sizeof(uint64_t);
|
1041 | f7d0fe02 | Kevin Wolf | |
1042 | f7d0fe02 | Kevin Wolf | /* Mark L1 table as used */
|
1043 | 9ac228e0 | Kevin Wolf | inc_refcounts(bs, res, refcount_table, refcount_table_size, |
1044 | 9ac228e0 | Kevin Wolf | l1_table_offset, l1_size2); |
1045 | f7d0fe02 | Kevin Wolf | |
1046 | f7d0fe02 | Kevin Wolf | /* Read L1 table entries from disk */
|
1047 | 702ef63f | Kevin Wolf | if (l1_size2 == 0) { |
1048 | 702ef63f | Kevin Wolf | l1_table = NULL;
|
1049 | 702ef63f | Kevin Wolf | } else {
|
1050 | 7267c094 | Anthony Liguori | l1_table = g_malloc(l1_size2); |
1051 | 66f82cee | Kevin Wolf | if (bdrv_pread(bs->file, l1_table_offset,
|
1052 | 702ef63f | Kevin Wolf | l1_table, l1_size2) != l1_size2) |
1053 | 702ef63f | Kevin Wolf | goto fail;
|
1054 | 702ef63f | Kevin Wolf | for(i = 0;i < l1_size; i++) |
1055 | 702ef63f | Kevin Wolf | be64_to_cpus(&l1_table[i]); |
1056 | 702ef63f | Kevin Wolf | } |
1057 | f7d0fe02 | Kevin Wolf | |
1058 | f7d0fe02 | Kevin Wolf | /* Do the actual checks */
|
1059 | f7d0fe02 | Kevin Wolf | for(i = 0; i < l1_size; i++) { |
1060 | f7d0fe02 | Kevin Wolf | l2_offset = l1_table[i]; |
1061 | f7d0fe02 | Kevin Wolf | if (l2_offset) {
|
1062 | f7d0fe02 | Kevin Wolf | /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
|
1063 | f7d0fe02 | Kevin Wolf | if (check_copied) {
|
1064 | f7d0fe02 | Kevin Wolf | refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED) |
1065 | f7d0fe02 | Kevin Wolf | >> s->cluster_bits); |
1066 | 018faafd | Kevin Wolf | if (refcount < 0) { |
1067 | 018faafd | Kevin Wolf | fprintf(stderr, "Can't get refcount for l2_offset %"
|
1068 | 018faafd | Kevin Wolf | PRIx64 ": %s\n", l2_offset, strerror(-refcount));
|
1069 | 9ac228e0 | Kevin Wolf | goto fail;
|
1070 | 018faafd | Kevin Wolf | } |
1071 | f7d0fe02 | Kevin Wolf | if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { |
1072 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
|
1073 | f7d0fe02 | Kevin Wolf | " refcount=%d\n", l2_offset, refcount);
|
1074 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
1075 | f7d0fe02 | Kevin Wolf | } |
1076 | f7d0fe02 | Kevin Wolf | } |
1077 | f7d0fe02 | Kevin Wolf | |
1078 | f7d0fe02 | Kevin Wolf | /* Mark L2 table as used */
|
1079 | afdf0abe | Kevin Wolf | l2_offset &= L1E_OFFSET_MASK; |
1080 | 9ac228e0 | Kevin Wolf | inc_refcounts(bs, res, refcount_table, refcount_table_size, |
1081 | 9ac228e0 | Kevin Wolf | l2_offset, s->cluster_size); |
1082 | f7d0fe02 | Kevin Wolf | |
1083 | f7d0fe02 | Kevin Wolf | /* L2 tables are cluster aligned */
|
1084 | f7d0fe02 | Kevin Wolf | if (l2_offset & (s->cluster_size - 1)) { |
1085 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not " |
1086 | f7d0fe02 | Kevin Wolf | "cluster aligned; L1 entry corrupted\n", l2_offset);
|
1087 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
1088 | f7d0fe02 | Kevin Wolf | } |
1089 | f7d0fe02 | Kevin Wolf | |
1090 | f7d0fe02 | Kevin Wolf | /* Process and check L2 entries */
|
1091 | 9ac228e0 | Kevin Wolf | ret = check_refcounts_l2(bs, res, refcount_table, |
1092 | 9ac228e0 | Kevin Wolf | refcount_table_size, l2_offset, check_copied); |
1093 | f7d0fe02 | Kevin Wolf | if (ret < 0) { |
1094 | f7d0fe02 | Kevin Wolf | goto fail;
|
1095 | f7d0fe02 | Kevin Wolf | } |
1096 | f7d0fe02 | Kevin Wolf | } |
1097 | f7d0fe02 | Kevin Wolf | } |
1098 | 7267c094 | Anthony Liguori | g_free(l1_table); |
1099 | 9ac228e0 | Kevin Wolf | return 0; |
1100 | f7d0fe02 | Kevin Wolf | |
1101 | f7d0fe02 | Kevin Wolf | fail:
|
1102 | f7d0fe02 | Kevin Wolf | fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
|
1103 | 9ac228e0 | Kevin Wolf | res->check_errors++; |
1104 | 7267c094 | Anthony Liguori | g_free(l1_table); |
1105 | f7d0fe02 | Kevin Wolf | return -EIO;
|
1106 | f7d0fe02 | Kevin Wolf | } |
1107 | f7d0fe02 | Kevin Wolf | |
1108 | f7d0fe02 | Kevin Wolf | /*
|
1109 | f7d0fe02 | Kevin Wolf | * Checks an image for refcount consistency.
|
1110 | f7d0fe02 | Kevin Wolf | *
|
1111 | f7d0fe02 | Kevin Wolf | * Returns 0 if no errors are found, the number of errors in case the image is
|
1112 | a1c7273b | Stefan Weil | * detected as corrupted, and -errno when an internal error occurred.
|
1113 | f7d0fe02 | Kevin Wolf | */
|
1114 | 166acf54 | Kevin Wolf | int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
|
1115 | 166acf54 | Kevin Wolf | BdrvCheckMode fix) |
1116 | f7d0fe02 | Kevin Wolf | { |
1117 | f7d0fe02 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
1118 | 166acf54 | Kevin Wolf | int64_t size, i; |
1119 | 166acf54 | Kevin Wolf | int nb_clusters, refcount1, refcount2;
|
1120 | f7d0fe02 | Kevin Wolf | QCowSnapshot *sn; |
1121 | f7d0fe02 | Kevin Wolf | uint16_t *refcount_table; |
1122 | 9ac228e0 | Kevin Wolf | int ret;
|
1123 | f7d0fe02 | Kevin Wolf | |
1124 | 66f82cee | Kevin Wolf | size = bdrv_getlength(bs->file); |
1125 | f7d0fe02 | Kevin Wolf | nb_clusters = size_to_clusters(s, size); |
1126 | 7267c094 | Anthony Liguori | refcount_table = g_malloc0(nb_clusters * sizeof(uint16_t));
|
1127 | f7d0fe02 | Kevin Wolf | |
1128 | f7d0fe02 | Kevin Wolf | /* header */
|
1129 | 9ac228e0 | Kevin Wolf | inc_refcounts(bs, res, refcount_table, nb_clusters, |
1130 | 9ac228e0 | Kevin Wolf | 0, s->cluster_size);
|
1131 | f7d0fe02 | Kevin Wolf | |
1132 | f7d0fe02 | Kevin Wolf | /* current L1 table */
|
1133 | 9ac228e0 | Kevin Wolf | ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters, |
1134 | f7d0fe02 | Kevin Wolf | s->l1_table_offset, s->l1_size, 1);
|
1135 | f7d0fe02 | Kevin Wolf | if (ret < 0) { |
1136 | 80fa3341 | Kevin Wolf | goto fail;
|
1137 | f7d0fe02 | Kevin Wolf | } |
1138 | f7d0fe02 | Kevin Wolf | |
1139 | f7d0fe02 | Kevin Wolf | /* snapshots */
|
1140 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->nb_snapshots; i++) { |
1141 | f7d0fe02 | Kevin Wolf | sn = s->snapshots + i; |
1142 | 9ac228e0 | Kevin Wolf | ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters, |
1143 | 9ac228e0 | Kevin Wolf | sn->l1_table_offset, sn->l1_size, 0);
|
1144 | 9ac228e0 | Kevin Wolf | if (ret < 0) { |
1145 | 80fa3341 | Kevin Wolf | goto fail;
|
1146 | 9ac228e0 | Kevin Wolf | } |
1147 | f7d0fe02 | Kevin Wolf | } |
1148 | 9ac228e0 | Kevin Wolf | inc_refcounts(bs, res, refcount_table, nb_clusters, |
1149 | 9ac228e0 | Kevin Wolf | s->snapshots_offset, s->snapshots_size); |
1150 | f7d0fe02 | Kevin Wolf | |
1151 | f7d0fe02 | Kevin Wolf | /* refcount data */
|
1152 | 9ac228e0 | Kevin Wolf | inc_refcounts(bs, res, refcount_table, nb_clusters, |
1153 | 9ac228e0 | Kevin Wolf | s->refcount_table_offset, |
1154 | 9ac228e0 | Kevin Wolf | s->refcount_table_size * sizeof(uint64_t));
|
1155 | 9ac228e0 | Kevin Wolf | |
1156 | f7d0fe02 | Kevin Wolf | for(i = 0; i < s->refcount_table_size; i++) { |
1157 | 6882c8fa | Kevin Wolf | uint64_t offset, cluster; |
1158 | f7d0fe02 | Kevin Wolf | offset = s->refcount_table[i]; |
1159 | 6882c8fa | Kevin Wolf | cluster = offset >> s->cluster_bits; |
1160 | 746c3cb5 | Kevin Wolf | |
1161 | 746c3cb5 | Kevin Wolf | /* Refcount blocks are cluster aligned */
|
1162 | 746c3cb5 | Kevin Wolf | if (offset & (s->cluster_size - 1)) { |
1163 | 166acf54 | Kevin Wolf | fprintf(stderr, "ERROR refcount block %" PRId64 " is not " |
1164 | 746c3cb5 | Kevin Wolf | "cluster aligned; refcount table entry corrupted\n", i);
|
1165 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
1166 | 6882c8fa | Kevin Wolf | continue;
|
1167 | 6882c8fa | Kevin Wolf | } |
1168 | 6882c8fa | Kevin Wolf | |
1169 | 6882c8fa | Kevin Wolf | if (cluster >= nb_clusters) {
|
1170 | 166acf54 | Kevin Wolf | fprintf(stderr, "ERROR refcount block %" PRId64
|
1171 | 166acf54 | Kevin Wolf | " is outside image\n", i);
|
1172 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
1173 | 6882c8fa | Kevin Wolf | continue;
|
1174 | 746c3cb5 | Kevin Wolf | } |
1175 | 746c3cb5 | Kevin Wolf | |
1176 | f7d0fe02 | Kevin Wolf | if (offset != 0) { |
1177 | 9ac228e0 | Kevin Wolf | inc_refcounts(bs, res, refcount_table, nb_clusters, |
1178 | 9ac228e0 | Kevin Wolf | offset, s->cluster_size); |
1179 | 6882c8fa | Kevin Wolf | if (refcount_table[cluster] != 1) { |
1180 | 166acf54 | Kevin Wolf | fprintf(stderr, "ERROR refcount block %" PRId64
|
1181 | 166acf54 | Kevin Wolf | " refcount=%d\n",
|
1182 | 6882c8fa | Kevin Wolf | i, refcount_table[cluster]); |
1183 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
1184 | 746c3cb5 | Kevin Wolf | } |
1185 | f7d0fe02 | Kevin Wolf | } |
1186 | f7d0fe02 | Kevin Wolf | } |
1187 | f7d0fe02 | Kevin Wolf | |
1188 | f7d0fe02 | Kevin Wolf | /* compare ref counts */
|
1189 | f7d0fe02 | Kevin Wolf | for(i = 0; i < nb_clusters; i++) { |
1190 | f7d0fe02 | Kevin Wolf | refcount1 = get_refcount(bs, i); |
1191 | 018faafd | Kevin Wolf | if (refcount1 < 0) { |
1192 | 166acf54 | Kevin Wolf | fprintf(stderr, "Can't get refcount for cluster %" PRId64 ": %s\n", |
1193 | 018faafd | Kevin Wolf | i, strerror(-refcount1)); |
1194 | 9ac228e0 | Kevin Wolf | res->check_errors++; |
1195 | f74550fd | Kevin Wolf | continue;
|
1196 | 018faafd | Kevin Wolf | } |
1197 | 018faafd | Kevin Wolf | |
1198 | f7d0fe02 | Kevin Wolf | refcount2 = refcount_table[i]; |
1199 | f7d0fe02 | Kevin Wolf | if (refcount1 != refcount2) {
|
1200 | 166acf54 | Kevin Wolf | |
1201 | 166acf54 | Kevin Wolf | /* Check if we're allowed to fix the mismatch */
|
1202 | 166acf54 | Kevin Wolf | int *num_fixed = NULL; |
1203 | 166acf54 | Kevin Wolf | if (refcount1 > refcount2 && (fix & BDRV_FIX_LEAKS)) {
|
1204 | 166acf54 | Kevin Wolf | num_fixed = &res->leaks_fixed; |
1205 | 166acf54 | Kevin Wolf | } else if (refcount1 < refcount2 && (fix & BDRV_FIX_ERRORS)) { |
1206 | 166acf54 | Kevin Wolf | num_fixed = &res->corruptions_fixed; |
1207 | 166acf54 | Kevin Wolf | } |
1208 | 166acf54 | Kevin Wolf | |
1209 | 166acf54 | Kevin Wolf | fprintf(stderr, "%s cluster %" PRId64 " refcount=%d reference=%d\n", |
1210 | 166acf54 | Kevin Wolf | num_fixed != NULL ? "Repairing" : |
1211 | 166acf54 | Kevin Wolf | refcount1 < refcount2 ? "ERROR" :
|
1212 | 166acf54 | Kevin Wolf | "Leaked",
|
1213 | f7d0fe02 | Kevin Wolf | i, refcount1, refcount2); |
1214 | 166acf54 | Kevin Wolf | |
1215 | 166acf54 | Kevin Wolf | if (num_fixed) {
|
1216 | 166acf54 | Kevin Wolf | ret = update_refcount(bs, i << s->cluster_bits, 1,
|
1217 | 166acf54 | Kevin Wolf | refcount2 - refcount1); |
1218 | 166acf54 | Kevin Wolf | if (ret >= 0) { |
1219 | 166acf54 | Kevin Wolf | (*num_fixed)++; |
1220 | 166acf54 | Kevin Wolf | continue;
|
1221 | 166acf54 | Kevin Wolf | } |
1222 | 166acf54 | Kevin Wolf | } |
1223 | 166acf54 | Kevin Wolf | |
1224 | 166acf54 | Kevin Wolf | /* And if we couldn't, print an error */
|
1225 | 9ac228e0 | Kevin Wolf | if (refcount1 < refcount2) {
|
1226 | 9ac228e0 | Kevin Wolf | res->corruptions++; |
1227 | 9ac228e0 | Kevin Wolf | } else {
|
1228 | 9ac228e0 | Kevin Wolf | res->leaks++; |
1229 | 9ac228e0 | Kevin Wolf | } |
1230 | f7d0fe02 | Kevin Wolf | } |
1231 | f7d0fe02 | Kevin Wolf | } |
1232 | f7d0fe02 | Kevin Wolf | |
1233 | 80fa3341 | Kevin Wolf | ret = 0;
|
1234 | 80fa3341 | Kevin Wolf | |
1235 | 80fa3341 | Kevin Wolf | fail:
|
1236 | 7267c094 | Anthony Liguori | g_free(refcount_table); |
1237 | f7d0fe02 | Kevin Wolf | |
1238 | 80fa3341 | Kevin Wolf | return ret;
|
1239 | f7d0fe02 | Kevin Wolf | } |