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/*
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* Block driver for the QCOW version 2 format
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*
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* Copyright (c) 2004-2006 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h" |
25 |
#include "block_int.h" |
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#include "module.h" |
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#include <zlib.h> |
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#include "aes.h" |
29 |
#include "block/qcow2.h" |
30 |
#include "qemu-error.h" |
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#include "qerror.h" |
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/*
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Differences with QCOW:
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|
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- Support for multiple incremental snapshots.
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- Memory management by reference counts.
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- Clusters which have a reference count of one have the bit
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QCOW_OFLAG_COPIED to optimize write performance.
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- Size of compressed clusters is stored in sectors to reduce bit usage
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in the cluster offsets.
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- Support for storing additional data (such as the VM state) in the
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snapshots.
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- If a backing store is used, the cluster size is not constrained
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(could be backported to QCOW).
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- L2 tables have always a size of one cluster.
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*/
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|
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|
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typedef struct { |
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uint32_t magic; |
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uint32_t len; |
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} QCowExtension; |
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#define QCOW2_EXT_MAGIC_END 0 |
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#define QCOW2_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA |
56 |
|
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static int qcow2_probe(const uint8_t *buf, int buf_size, const char *filename) |
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{ |
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const QCowHeader *cow_header = (const void *)buf; |
60 |
|
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if (buf_size >= sizeof(QCowHeader) && |
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be32_to_cpu(cow_header->magic) == QCOW_MAGIC && |
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be32_to_cpu(cow_header->version) >= QCOW_VERSION) |
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return 100; |
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else
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return 0; |
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} |
68 |
|
69 |
|
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/*
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* read qcow2 extension and fill bs
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* start reading from start_offset
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* finish reading upon magic of value 0 or when end_offset reached
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* unknown magic is skipped (future extension this version knows nothing about)
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* return 0 upon success, non-0 otherwise
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*/
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static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, |
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uint64_t end_offset) |
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{ |
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QCowExtension ext; |
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uint64_t offset; |
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|
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#ifdef DEBUG_EXT
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printf("qcow2_read_extensions: start=%ld end=%ld\n", start_offset, end_offset);
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#endif
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offset = start_offset; |
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while (offset < end_offset) {
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|
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#ifdef DEBUG_EXT
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BDRVQcowState *s = bs->opaque; |
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/* Sanity check */
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if (offset > s->cluster_size)
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printf("qcow2_read_extension: suspicious offset %lu\n", offset);
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|
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printf("attemting to read extended header in offset %lu\n", offset);
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#endif
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|
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if (bdrv_pread(bs->file, offset, &ext, sizeof(ext)) != sizeof(ext)) { |
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fprintf(stderr, "qcow2_read_extension: ERROR: "
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"pread fail from offset %" PRIu64 "\n", |
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offset); |
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return 1; |
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} |
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be32_to_cpus(&ext.magic); |
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be32_to_cpus(&ext.len); |
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offset += sizeof(ext);
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#ifdef DEBUG_EXT
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printf("ext.magic = 0x%x\n", ext.magic);
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#endif
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switch (ext.magic) {
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case QCOW2_EXT_MAGIC_END:
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return 0; |
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case QCOW2_EXT_MAGIC_BACKING_FORMAT:
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if (ext.len >= sizeof(bs->backing_format)) { |
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fprintf(stderr, "ERROR: ext_backing_format: len=%u too large"
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" (>=%zu)\n",
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ext.len, sizeof(bs->backing_format));
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return 2; |
120 |
} |
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if (bdrv_pread(bs->file, offset , bs->backing_format,
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ext.len) != ext.len) |
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return 3; |
124 |
bs->backing_format[ext.len] = '\0';
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#ifdef DEBUG_EXT
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printf("Qcow2: Got format extension %s\n", bs->backing_format);
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#endif
|
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offset = ((offset + ext.len + 7) & ~7); |
129 |
break;
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130 |
|
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default:
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/* unknown magic -- just skip it */
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offset = ((offset + ext.len + 7) & ~7); |
134 |
break;
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} |
136 |
} |
137 |
|
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return 0; |
139 |
} |
140 |
|
141 |
|
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static int qcow2_open(BlockDriverState *bs, int flags) |
143 |
{ |
144 |
BDRVQcowState *s = bs->opaque; |
145 |
int len, i, ret = 0; |
146 |
QCowHeader header; |
147 |
uint64_t ext_end; |
148 |
bool writethrough;
|
149 |
|
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ret = bdrv_pread(bs->file, 0, &header, sizeof(header)); |
151 |
if (ret < 0) { |
152 |
goto fail;
|
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} |
154 |
be32_to_cpus(&header.magic); |
155 |
be32_to_cpus(&header.version); |
156 |
be64_to_cpus(&header.backing_file_offset); |
157 |
be32_to_cpus(&header.backing_file_size); |
158 |
be64_to_cpus(&header.size); |
159 |
be32_to_cpus(&header.cluster_bits); |
160 |
be32_to_cpus(&header.crypt_method); |
161 |
be64_to_cpus(&header.l1_table_offset); |
162 |
be32_to_cpus(&header.l1_size); |
163 |
be64_to_cpus(&header.refcount_table_offset); |
164 |
be32_to_cpus(&header.refcount_table_clusters); |
165 |
be64_to_cpus(&header.snapshots_offset); |
166 |
be32_to_cpus(&header.nb_snapshots); |
167 |
|
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if (header.magic != QCOW_MAGIC) {
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ret = -EINVAL; |
170 |
goto fail;
|
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} |
172 |
if (header.version != QCOW_VERSION) {
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char version[64]; |
174 |
snprintf(version, sizeof(version), "QCOW version %d", header.version); |
175 |
qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, |
176 |
bs->device_name, "qcow2", version);
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ret = -ENOTSUP; |
178 |
goto fail;
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} |
180 |
if (header.cluster_bits < MIN_CLUSTER_BITS ||
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header.cluster_bits > MAX_CLUSTER_BITS) { |
182 |
ret = -EINVAL; |
183 |
goto fail;
|
184 |
} |
185 |
if (header.crypt_method > QCOW_CRYPT_AES) {
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ret = -EINVAL; |
187 |
goto fail;
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188 |
} |
189 |
s->crypt_method_header = header.crypt_method; |
190 |
if (s->crypt_method_header) {
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bs->encrypted = 1;
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} |
193 |
s->cluster_bits = header.cluster_bits; |
194 |
s->cluster_size = 1 << s->cluster_bits;
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s->cluster_sectors = 1 << (s->cluster_bits - 9); |
196 |
s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ |
197 |
s->l2_size = 1 << s->l2_bits;
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bs->total_sectors = header.size / 512;
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s->csize_shift = (62 - (s->cluster_bits - 8)); |
200 |
s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; |
201 |
s->cluster_offset_mask = (1LL << s->csize_shift) - 1; |
202 |
s->refcount_table_offset = header.refcount_table_offset; |
203 |
s->refcount_table_size = |
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header.refcount_table_clusters << (s->cluster_bits - 3);
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|
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s->snapshots_offset = header.snapshots_offset; |
207 |
s->nb_snapshots = header.nb_snapshots; |
208 |
|
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/* read the level 1 table */
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s->l1_size = header.l1_size; |
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s->l1_vm_state_index = size_to_l1(s, header.size); |
212 |
/* the L1 table must contain at least enough entries to put
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213 |
header.size bytes */
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if (s->l1_size < s->l1_vm_state_index) {
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ret = -EINVAL; |
216 |
goto fail;
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} |
218 |
s->l1_table_offset = header.l1_table_offset; |
219 |
if (s->l1_size > 0) { |
220 |
s->l1_table = g_malloc0( |
221 |
align_offset(s->l1_size * sizeof(uint64_t), 512)); |
222 |
ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, |
223 |
s->l1_size * sizeof(uint64_t));
|
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if (ret < 0) { |
225 |
goto fail;
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226 |
} |
227 |
for(i = 0;i < s->l1_size; i++) { |
228 |
be64_to_cpus(&s->l1_table[i]); |
229 |
} |
230 |
} |
231 |
|
232 |
/* alloc L2 table/refcount block cache */
|
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writethrough = ((flags & BDRV_O_CACHE_WB) == 0);
|
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s->l2_table_cache = qcow2_cache_create(bs, L2_CACHE_SIZE, writethrough); |
235 |
s->refcount_block_cache = qcow2_cache_create(bs, REFCOUNT_CACHE_SIZE, |
236 |
writethrough); |
237 |
|
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s->cluster_cache = g_malloc(s->cluster_size); |
239 |
/* one more sector for decompressed data alignment */
|
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s->cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size |
241 |
+ 512);
|
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s->cluster_cache_offset = -1;
|
243 |
s->flags = flags; |
244 |
|
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ret = qcow2_refcount_init(bs); |
246 |
if (ret != 0) { |
247 |
goto fail;
|
248 |
} |
249 |
|
250 |
QLIST_INIT(&s->cluster_allocs); |
251 |
|
252 |
/* read qcow2 extensions */
|
253 |
if (header.backing_file_offset) {
|
254 |
ext_end = header.backing_file_offset; |
255 |
} else {
|
256 |
ext_end = s->cluster_size; |
257 |
} |
258 |
if (qcow2_read_extensions(bs, sizeof(header), ext_end)) { |
259 |
ret = -EINVAL; |
260 |
goto fail;
|
261 |
} |
262 |
|
263 |
/* read the backing file name */
|
264 |
if (header.backing_file_offset != 0) { |
265 |
len = header.backing_file_size; |
266 |
if (len > 1023) { |
267 |
len = 1023;
|
268 |
} |
269 |
ret = bdrv_pread(bs->file, header.backing_file_offset, |
270 |
bs->backing_file, len); |
271 |
if (ret < 0) { |
272 |
goto fail;
|
273 |
} |
274 |
bs->backing_file[len] = '\0';
|
275 |
} |
276 |
|
277 |
ret = qcow2_read_snapshots(bs); |
278 |
if (ret < 0) { |
279 |
goto fail;
|
280 |
} |
281 |
|
282 |
/* Initialise locks */
|
283 |
qemu_co_mutex_init(&s->lock); |
284 |
|
285 |
#ifdef DEBUG_ALLOC
|
286 |
{ |
287 |
BdrvCheckResult result = {0};
|
288 |
qcow2_check_refcounts(bs, &result); |
289 |
} |
290 |
#endif
|
291 |
return ret;
|
292 |
|
293 |
fail:
|
294 |
qcow2_free_snapshots(bs); |
295 |
qcow2_refcount_close(bs); |
296 |
g_free(s->l1_table); |
297 |
if (s->l2_table_cache) {
|
298 |
qcow2_cache_destroy(bs, s->l2_table_cache); |
299 |
} |
300 |
g_free(s->cluster_cache); |
301 |
qemu_vfree(s->cluster_data); |
302 |
return ret;
|
303 |
} |
304 |
|
305 |
static int qcow2_set_key(BlockDriverState *bs, const char *key) |
306 |
{ |
307 |
BDRVQcowState *s = bs->opaque; |
308 |
uint8_t keybuf[16];
|
309 |
int len, i;
|
310 |
|
311 |
memset(keybuf, 0, 16); |
312 |
len = strlen(key); |
313 |
if (len > 16) |
314 |
len = 16;
|
315 |
/* XXX: we could compress the chars to 7 bits to increase
|
316 |
entropy */
|
317 |
for(i = 0;i < len;i++) { |
318 |
keybuf[i] = key[i]; |
319 |
} |
320 |
s->crypt_method = s->crypt_method_header; |
321 |
|
322 |
if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) |
323 |
return -1; |
324 |
if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) |
325 |
return -1; |
326 |
#if 0
|
327 |
/* test */
|
328 |
{
|
329 |
uint8_t in[16];
|
330 |
uint8_t out[16];
|
331 |
uint8_t tmp[16];
|
332 |
for(i=0;i<16;i++)
|
333 |
in[i] = i;
|
334 |
AES_encrypt(in, tmp, &s->aes_encrypt_key);
|
335 |
AES_decrypt(tmp, out, &s->aes_decrypt_key);
|
336 |
for(i = 0; i < 16; i++)
|
337 |
printf(" %02x", tmp[i]);
|
338 |
printf("\n");
|
339 |
for(i = 0; i < 16; i++)
|
340 |
printf(" %02x", out[i]);
|
341 |
printf("\n");
|
342 |
}
|
343 |
#endif
|
344 |
return 0; |
345 |
} |
346 |
|
347 |
static int coroutine_fn qcow2_co_is_allocated(BlockDriverState *bs, |
348 |
int64_t sector_num, int nb_sectors, int *pnum) |
349 |
{ |
350 |
BDRVQcowState *s = bs->opaque; |
351 |
uint64_t cluster_offset; |
352 |
int ret;
|
353 |
|
354 |
*pnum = nb_sectors; |
355 |
/* FIXME We can get errors here, but the bdrv_co_is_allocated interface
|
356 |
* can't pass them on today */
|
357 |
qemu_co_mutex_lock(&s->lock); |
358 |
ret = qcow2_get_cluster_offset(bs, sector_num << 9, pnum, &cluster_offset);
|
359 |
qemu_co_mutex_unlock(&s->lock); |
360 |
if (ret < 0) { |
361 |
*pnum = 0;
|
362 |
} |
363 |
|
364 |
return (cluster_offset != 0); |
365 |
} |
366 |
|
367 |
/* handle reading after the end of the backing file */
|
368 |
int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
|
369 |
int64_t sector_num, int nb_sectors)
|
370 |
{ |
371 |
int n1;
|
372 |
if ((sector_num + nb_sectors) <= bs->total_sectors)
|
373 |
return nb_sectors;
|
374 |
if (sector_num >= bs->total_sectors)
|
375 |
n1 = 0;
|
376 |
else
|
377 |
n1 = bs->total_sectors - sector_num; |
378 |
|
379 |
qemu_iovec_memset_skip(qiov, 0, 512 * (nb_sectors - n1), 512 * n1); |
380 |
|
381 |
return n1;
|
382 |
} |
383 |
|
384 |
static coroutine_fn int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num, |
385 |
int remaining_sectors, QEMUIOVector *qiov)
|
386 |
{ |
387 |
BDRVQcowState *s = bs->opaque; |
388 |
int index_in_cluster, n1;
|
389 |
int ret;
|
390 |
int cur_nr_sectors; /* number of sectors in current iteration */ |
391 |
uint64_t cluster_offset = 0;
|
392 |
uint64_t bytes_done = 0;
|
393 |
QEMUIOVector hd_qiov; |
394 |
uint8_t *cluster_data = NULL;
|
395 |
|
396 |
qemu_iovec_init(&hd_qiov, qiov->niov); |
397 |
|
398 |
qemu_co_mutex_lock(&s->lock); |
399 |
|
400 |
while (remaining_sectors != 0) { |
401 |
|
402 |
/* prepare next request */
|
403 |
cur_nr_sectors = remaining_sectors; |
404 |
if (s->crypt_method) {
|
405 |
cur_nr_sectors = MIN(cur_nr_sectors, |
406 |
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); |
407 |
} |
408 |
|
409 |
ret = qcow2_get_cluster_offset(bs, sector_num << 9,
|
410 |
&cur_nr_sectors, &cluster_offset); |
411 |
if (ret < 0) { |
412 |
goto fail;
|
413 |
} |
414 |
|
415 |
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
416 |
|
417 |
qemu_iovec_reset(&hd_qiov); |
418 |
qemu_iovec_copy(&hd_qiov, qiov, bytes_done, |
419 |
cur_nr_sectors * 512);
|
420 |
|
421 |
if (!cluster_offset) {
|
422 |
|
423 |
if (bs->backing_hd) {
|
424 |
/* read from the base image */
|
425 |
n1 = qcow2_backing_read1(bs->backing_hd, &hd_qiov, |
426 |
sector_num, cur_nr_sectors); |
427 |
if (n1 > 0) { |
428 |
BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO); |
429 |
qemu_co_mutex_unlock(&s->lock); |
430 |
ret = bdrv_co_readv(bs->backing_hd, sector_num, |
431 |
n1, &hd_qiov); |
432 |
qemu_co_mutex_lock(&s->lock); |
433 |
if (ret < 0) { |
434 |
goto fail;
|
435 |
} |
436 |
} |
437 |
} else {
|
438 |
/* Note: in this case, no need to wait */
|
439 |
qemu_iovec_memset(&hd_qiov, 0, 512 * cur_nr_sectors); |
440 |
} |
441 |
} else if (cluster_offset & QCOW_OFLAG_COMPRESSED) { |
442 |
/* add AIO support for compressed blocks ? */
|
443 |
ret = qcow2_decompress_cluster(bs, cluster_offset); |
444 |
if (ret < 0) { |
445 |
goto fail;
|
446 |
} |
447 |
|
448 |
qemu_iovec_from_buffer(&hd_qiov, |
449 |
s->cluster_cache + index_in_cluster * 512,
|
450 |
512 * cur_nr_sectors);
|
451 |
} else {
|
452 |
if ((cluster_offset & 511) != 0) { |
453 |
ret = -EIO; |
454 |
goto fail;
|
455 |
} |
456 |
|
457 |
if (s->crypt_method) {
|
458 |
/*
|
459 |
* For encrypted images, read everything into a temporary
|
460 |
* contiguous buffer on which the AES functions can work.
|
461 |
*/
|
462 |
if (!cluster_data) {
|
463 |
cluster_data = |
464 |
qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); |
465 |
} |
466 |
|
467 |
assert(cur_nr_sectors <= |
468 |
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); |
469 |
qemu_iovec_reset(&hd_qiov); |
470 |
qemu_iovec_add(&hd_qiov, cluster_data, |
471 |
512 * cur_nr_sectors);
|
472 |
} |
473 |
|
474 |
BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); |
475 |
qemu_co_mutex_unlock(&s->lock); |
476 |
ret = bdrv_co_readv(bs->file, |
477 |
(cluster_offset >> 9) + index_in_cluster,
|
478 |
cur_nr_sectors, &hd_qiov); |
479 |
qemu_co_mutex_lock(&s->lock); |
480 |
if (ret < 0) { |
481 |
goto fail;
|
482 |
} |
483 |
if (s->crypt_method) {
|
484 |
qcow2_encrypt_sectors(s, sector_num, cluster_data, |
485 |
cluster_data, cur_nr_sectors, 0, &s->aes_decrypt_key);
|
486 |
qemu_iovec_reset(&hd_qiov); |
487 |
qemu_iovec_copy(&hd_qiov, qiov, bytes_done, |
488 |
cur_nr_sectors * 512);
|
489 |
qemu_iovec_from_buffer(&hd_qiov, cluster_data, |
490 |
512 * cur_nr_sectors);
|
491 |
} |
492 |
} |
493 |
|
494 |
remaining_sectors -= cur_nr_sectors; |
495 |
sector_num += cur_nr_sectors; |
496 |
bytes_done += cur_nr_sectors * 512;
|
497 |
} |
498 |
ret = 0;
|
499 |
|
500 |
fail:
|
501 |
qemu_co_mutex_unlock(&s->lock); |
502 |
|
503 |
qemu_iovec_destroy(&hd_qiov); |
504 |
qemu_vfree(cluster_data); |
505 |
|
506 |
return ret;
|
507 |
} |
508 |
|
509 |
static void run_dependent_requests(BDRVQcowState *s, QCowL2Meta *m) |
510 |
{ |
511 |
/* Take the request off the list of running requests */
|
512 |
if (m->nb_clusters != 0) { |
513 |
QLIST_REMOVE(m, next_in_flight); |
514 |
} |
515 |
|
516 |
/* Restart all dependent requests */
|
517 |
if (!qemu_co_queue_empty(&m->dependent_requests)) {
|
518 |
qemu_co_mutex_unlock(&s->lock); |
519 |
while(qemu_co_queue_next(&m->dependent_requests));
|
520 |
qemu_co_mutex_lock(&s->lock); |
521 |
} |
522 |
} |
523 |
|
524 |
static coroutine_fn int qcow2_co_writev(BlockDriverState *bs, |
525 |
int64_t sector_num, |
526 |
int remaining_sectors,
|
527 |
QEMUIOVector *qiov) |
528 |
{ |
529 |
BDRVQcowState *s = bs->opaque; |
530 |
int index_in_cluster;
|
531 |
int n_end;
|
532 |
int ret;
|
533 |
int cur_nr_sectors; /* number of sectors in current iteration */ |
534 |
uint64_t cluster_offset; |
535 |
QEMUIOVector hd_qiov; |
536 |
uint64_t bytes_done = 0;
|
537 |
uint8_t *cluster_data = NULL;
|
538 |
QCowL2Meta l2meta = { |
539 |
.nb_clusters = 0,
|
540 |
}; |
541 |
|
542 |
qemu_co_queue_init(&l2meta.dependent_requests); |
543 |
|
544 |
qemu_iovec_init(&hd_qiov, qiov->niov); |
545 |
|
546 |
s->cluster_cache_offset = -1; /* disable compressed cache */ |
547 |
|
548 |
qemu_co_mutex_lock(&s->lock); |
549 |
|
550 |
while (remaining_sectors != 0) { |
551 |
|
552 |
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
553 |
n_end = index_in_cluster + remaining_sectors; |
554 |
if (s->crypt_method &&
|
555 |
n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) { |
556 |
n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; |
557 |
} |
558 |
|
559 |
ret = qcow2_alloc_cluster_offset(bs, sector_num << 9,
|
560 |
index_in_cluster, n_end, &cur_nr_sectors, &l2meta); |
561 |
if (ret < 0) { |
562 |
goto fail;
|
563 |
} |
564 |
|
565 |
cluster_offset = l2meta.cluster_offset; |
566 |
assert((cluster_offset & 511) == 0); |
567 |
|
568 |
qemu_iovec_reset(&hd_qiov); |
569 |
qemu_iovec_copy(&hd_qiov, qiov, bytes_done, |
570 |
cur_nr_sectors * 512);
|
571 |
|
572 |
if (s->crypt_method) {
|
573 |
if (!cluster_data) {
|
574 |
cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * |
575 |
s->cluster_size); |
576 |
} |
577 |
|
578 |
assert(hd_qiov.size <= |
579 |
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); |
580 |
qemu_iovec_to_buffer(&hd_qiov, cluster_data); |
581 |
|
582 |
qcow2_encrypt_sectors(s, sector_num, cluster_data, |
583 |
cluster_data, cur_nr_sectors, 1, &s->aes_encrypt_key);
|
584 |
|
585 |
qemu_iovec_reset(&hd_qiov); |
586 |
qemu_iovec_add(&hd_qiov, cluster_data, |
587 |
cur_nr_sectors * 512);
|
588 |
} |
589 |
|
590 |
BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); |
591 |
qemu_co_mutex_unlock(&s->lock); |
592 |
ret = bdrv_co_writev(bs->file, |
593 |
(cluster_offset >> 9) + index_in_cluster,
|
594 |
cur_nr_sectors, &hd_qiov); |
595 |
qemu_co_mutex_lock(&s->lock); |
596 |
if (ret < 0) { |
597 |
goto fail;
|
598 |
} |
599 |
|
600 |
ret = qcow2_alloc_cluster_link_l2(bs, &l2meta); |
601 |
if (ret < 0) { |
602 |
goto fail;
|
603 |
} |
604 |
|
605 |
run_dependent_requests(s, &l2meta); |
606 |
|
607 |
remaining_sectors -= cur_nr_sectors; |
608 |
sector_num += cur_nr_sectors; |
609 |
bytes_done += cur_nr_sectors * 512;
|
610 |
} |
611 |
ret = 0;
|
612 |
|
613 |
fail:
|
614 |
run_dependent_requests(s, &l2meta); |
615 |
|
616 |
qemu_co_mutex_unlock(&s->lock); |
617 |
|
618 |
qemu_iovec_destroy(&hd_qiov); |
619 |
qemu_vfree(cluster_data); |
620 |
|
621 |
return ret;
|
622 |
} |
623 |
|
624 |
static void qcow2_close(BlockDriverState *bs) |
625 |
{ |
626 |
BDRVQcowState *s = bs->opaque; |
627 |
g_free(s->l1_table); |
628 |
|
629 |
qcow2_cache_flush(bs, s->l2_table_cache); |
630 |
qcow2_cache_flush(bs, s->refcount_block_cache); |
631 |
|
632 |
qcow2_cache_destroy(bs, s->l2_table_cache); |
633 |
qcow2_cache_destroy(bs, s->refcount_block_cache); |
634 |
|
635 |
g_free(s->cluster_cache); |
636 |
qemu_vfree(s->cluster_data); |
637 |
qcow2_refcount_close(bs); |
638 |
} |
639 |
|
640 |
static void qcow2_invalidate_cache(BlockDriverState *bs) |
641 |
{ |
642 |
BDRVQcowState *s = bs->opaque; |
643 |
int flags = s->flags;
|
644 |
AES_KEY aes_encrypt_key; |
645 |
AES_KEY aes_decrypt_key; |
646 |
uint32_t crypt_method = 0;
|
647 |
|
648 |
/*
|
649 |
* Backing files are read-only which makes all of their metadata immutable,
|
650 |
* that means we don't have to worry about reopening them here.
|
651 |
*/
|
652 |
|
653 |
if (s->crypt_method) {
|
654 |
crypt_method = s->crypt_method; |
655 |
memcpy(&aes_encrypt_key, &s->aes_encrypt_key, sizeof(aes_encrypt_key));
|
656 |
memcpy(&aes_decrypt_key, &s->aes_decrypt_key, sizeof(aes_decrypt_key));
|
657 |
} |
658 |
|
659 |
qcow2_close(bs); |
660 |
|
661 |
memset(s, 0, sizeof(BDRVQcowState)); |
662 |
qcow2_open(bs, flags); |
663 |
|
664 |
if (crypt_method) {
|
665 |
s->crypt_method = crypt_method; |
666 |
memcpy(&s->aes_encrypt_key, &aes_encrypt_key, sizeof(aes_encrypt_key));
|
667 |
memcpy(&s->aes_decrypt_key, &aes_decrypt_key, sizeof(aes_decrypt_key));
|
668 |
} |
669 |
} |
670 |
|
671 |
/*
|
672 |
* Updates the variable length parts of the qcow2 header, i.e. the backing file
|
673 |
* name and all extensions. qcow2 was not designed to allow such changes, so if
|
674 |
* we run out of space (we can only use the first cluster) this function may
|
675 |
* fail.
|
676 |
*
|
677 |
* Returns 0 on success, -errno in error cases.
|
678 |
*/
|
679 |
static int qcow2_update_ext_header(BlockDriverState *bs, |
680 |
const char *backing_file, const char *backing_fmt) |
681 |
{ |
682 |
size_t backing_file_len = 0;
|
683 |
size_t backing_fmt_len = 0;
|
684 |
BDRVQcowState *s = bs->opaque; |
685 |
QCowExtension ext_backing_fmt = {0, 0}; |
686 |
int ret;
|
687 |
|
688 |
/* Backing file format doesn't make sense without a backing file */
|
689 |
if (backing_fmt && !backing_file) {
|
690 |
return -EINVAL;
|
691 |
} |
692 |
|
693 |
/* Prepare the backing file format extension if needed */
|
694 |
if (backing_fmt) {
|
695 |
ext_backing_fmt.len = cpu_to_be32(strlen(backing_fmt)); |
696 |
ext_backing_fmt.magic = cpu_to_be32(QCOW2_EXT_MAGIC_BACKING_FORMAT); |
697 |
backing_fmt_len = ((sizeof(ext_backing_fmt)
|
698 |
+ strlen(backing_fmt) + 7) & ~7); |
699 |
} |
700 |
|
701 |
/* Check if we can fit the new header into the first cluster */
|
702 |
if (backing_file) {
|
703 |
backing_file_len = strlen(backing_file); |
704 |
} |
705 |
|
706 |
size_t header_size = sizeof(QCowHeader) + backing_file_len
|
707 |
+ backing_fmt_len; |
708 |
|
709 |
if (header_size > s->cluster_size) {
|
710 |
return -ENOSPC;
|
711 |
} |
712 |
|
713 |
/* Rewrite backing file name and qcow2 extensions */
|
714 |
size_t ext_size = header_size - sizeof(QCowHeader);
|
715 |
uint8_t buf[ext_size]; |
716 |
size_t offset = 0;
|
717 |
size_t backing_file_offset = 0;
|
718 |
|
719 |
if (backing_file) {
|
720 |
if (backing_fmt) {
|
721 |
int padding = backing_fmt_len -
|
722 |
(sizeof(ext_backing_fmt) + strlen(backing_fmt));
|
723 |
|
724 |
memcpy(buf + offset, &ext_backing_fmt, sizeof(ext_backing_fmt));
|
725 |
offset += sizeof(ext_backing_fmt);
|
726 |
|
727 |
memcpy(buf + offset, backing_fmt, strlen(backing_fmt)); |
728 |
offset += strlen(backing_fmt); |
729 |
|
730 |
memset(buf + offset, 0, padding);
|
731 |
offset += padding; |
732 |
} |
733 |
|
734 |
memcpy(buf + offset, backing_file, backing_file_len); |
735 |
backing_file_offset = sizeof(QCowHeader) + offset;
|
736 |
} |
737 |
|
738 |
ret = bdrv_pwrite_sync(bs->file, sizeof(QCowHeader), buf, ext_size);
|
739 |
if (ret < 0) { |
740 |
goto fail;
|
741 |
} |
742 |
|
743 |
/* Update header fields */
|
744 |
uint64_t be_backing_file_offset = cpu_to_be64(backing_file_offset); |
745 |
uint32_t be_backing_file_size = cpu_to_be32(backing_file_len); |
746 |
|
747 |
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, backing_file_offset), |
748 |
&be_backing_file_offset, sizeof(uint64_t));
|
749 |
if (ret < 0) { |
750 |
goto fail;
|
751 |
} |
752 |
|
753 |
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, backing_file_size), |
754 |
&be_backing_file_size, sizeof(uint32_t));
|
755 |
if (ret < 0) { |
756 |
goto fail;
|
757 |
} |
758 |
|
759 |
ret = 0;
|
760 |
fail:
|
761 |
return ret;
|
762 |
} |
763 |
|
764 |
static int qcow2_change_backing_file(BlockDriverState *bs, |
765 |
const char *backing_file, const char *backing_fmt) |
766 |
{ |
767 |
return qcow2_update_ext_header(bs, backing_file, backing_fmt);
|
768 |
} |
769 |
|
770 |
static int preallocate(BlockDriverState *bs) |
771 |
{ |
772 |
uint64_t nb_sectors; |
773 |
uint64_t offset; |
774 |
int num;
|
775 |
int ret;
|
776 |
QCowL2Meta meta; |
777 |
|
778 |
nb_sectors = bdrv_getlength(bs) >> 9;
|
779 |
offset = 0;
|
780 |
qemu_co_queue_init(&meta.dependent_requests); |
781 |
meta.cluster_offset = 0;
|
782 |
|
783 |
while (nb_sectors) {
|
784 |
num = MIN(nb_sectors, INT_MAX >> 9);
|
785 |
ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num, &meta);
|
786 |
if (ret < 0) { |
787 |
return ret;
|
788 |
} |
789 |
|
790 |
ret = qcow2_alloc_cluster_link_l2(bs, &meta); |
791 |
if (ret < 0) { |
792 |
qcow2_free_any_clusters(bs, meta.cluster_offset, meta.nb_clusters); |
793 |
return ret;
|
794 |
} |
795 |
|
796 |
/* There are no dependent requests, but we need to remove our request
|
797 |
* from the list of in-flight requests */
|
798 |
run_dependent_requests(bs->opaque, &meta); |
799 |
|
800 |
/* TODO Preallocate data if requested */
|
801 |
|
802 |
nb_sectors -= num; |
803 |
offset += num << 9;
|
804 |
} |
805 |
|
806 |
/*
|
807 |
* It is expected that the image file is large enough to actually contain
|
808 |
* all of the allocated clusters (otherwise we get failing reads after
|
809 |
* EOF). Extend the image to the last allocated sector.
|
810 |
*/
|
811 |
if (meta.cluster_offset != 0) { |
812 |
uint8_t buf[512];
|
813 |
memset(buf, 0, 512); |
814 |
ret = bdrv_write(bs->file, (meta.cluster_offset >> 9) + num - 1, buf, 1); |
815 |
if (ret < 0) { |
816 |
return ret;
|
817 |
} |
818 |
} |
819 |
|
820 |
return 0; |
821 |
} |
822 |
|
823 |
static int qcow2_create2(const char *filename, int64_t total_size, |
824 |
const char *backing_file, const char *backing_format, |
825 |
int flags, size_t cluster_size, int prealloc, |
826 |
QEMUOptionParameter *options) |
827 |
{ |
828 |
/* Calulate cluster_bits */
|
829 |
int cluster_bits;
|
830 |
cluster_bits = ffs(cluster_size) - 1;
|
831 |
if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS ||
|
832 |
(1 << cluster_bits) != cluster_size)
|
833 |
{ |
834 |
error_report( |
835 |
"Cluster size must be a power of two between %d and %dk",
|
836 |
1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10)); |
837 |
return -EINVAL;
|
838 |
} |
839 |
|
840 |
/*
|
841 |
* Open the image file and write a minimal qcow2 header.
|
842 |
*
|
843 |
* We keep things simple and start with a zero-sized image. We also
|
844 |
* do without refcount blocks or a L1 table for now. We'll fix the
|
845 |
* inconsistency later.
|
846 |
*
|
847 |
* We do need a refcount table because growing the refcount table means
|
848 |
* allocating two new refcount blocks - the seconds of which would be at
|
849 |
* 2 GB for 64k clusters, and we don't want to have a 2 GB initial file
|
850 |
* size for any qcow2 image.
|
851 |
*/
|
852 |
BlockDriverState* bs; |
853 |
QCowHeader header; |
854 |
uint8_t* refcount_table; |
855 |
int ret;
|
856 |
|
857 |
ret = bdrv_create_file(filename, options); |
858 |
if (ret < 0) { |
859 |
return ret;
|
860 |
} |
861 |
|
862 |
ret = bdrv_file_open(&bs, filename, BDRV_O_RDWR); |
863 |
if (ret < 0) { |
864 |
return ret;
|
865 |
} |
866 |
|
867 |
/* Write the header */
|
868 |
memset(&header, 0, sizeof(header)); |
869 |
header.magic = cpu_to_be32(QCOW_MAGIC); |
870 |
header.version = cpu_to_be32(QCOW_VERSION); |
871 |
header.cluster_bits = cpu_to_be32(cluster_bits); |
872 |
header.size = cpu_to_be64(0);
|
873 |
header.l1_table_offset = cpu_to_be64(0);
|
874 |
header.l1_size = cpu_to_be32(0);
|
875 |
header.refcount_table_offset = cpu_to_be64(cluster_size); |
876 |
header.refcount_table_clusters = cpu_to_be32(1);
|
877 |
|
878 |
if (flags & BLOCK_FLAG_ENCRYPT) {
|
879 |
header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); |
880 |
} else {
|
881 |
header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); |
882 |
} |
883 |
|
884 |
ret = bdrv_pwrite(bs, 0, &header, sizeof(header)); |
885 |
if (ret < 0) { |
886 |
goto out;
|
887 |
} |
888 |
|
889 |
/* Write an empty refcount table */
|
890 |
refcount_table = g_malloc0(cluster_size); |
891 |
ret = bdrv_pwrite(bs, cluster_size, refcount_table, cluster_size); |
892 |
g_free(refcount_table); |
893 |
|
894 |
if (ret < 0) { |
895 |
goto out;
|
896 |
} |
897 |
|
898 |
bdrv_close(bs); |
899 |
|
900 |
/*
|
901 |
* And now open the image and make it consistent first (i.e. increase the
|
902 |
* refcount of the cluster that is occupied by the header and the refcount
|
903 |
* table)
|
904 |
*/
|
905 |
BlockDriver* drv = bdrv_find_format("qcow2");
|
906 |
assert(drv != NULL);
|
907 |
ret = bdrv_open(bs, filename, |
908 |
BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv); |
909 |
if (ret < 0) { |
910 |
goto out;
|
911 |
} |
912 |
|
913 |
ret = qcow2_alloc_clusters(bs, 2 * cluster_size);
|
914 |
if (ret < 0) { |
915 |
goto out;
|
916 |
|
917 |
} else if (ret != 0) { |
918 |
error_report("Huh, first cluster in empty image is already in use?");
|
919 |
abort(); |
920 |
} |
921 |
|
922 |
/* Okay, now that we have a valid image, let's give it the right size */
|
923 |
ret = bdrv_truncate(bs, total_size * BDRV_SECTOR_SIZE); |
924 |
if (ret < 0) { |
925 |
goto out;
|
926 |
} |
927 |
|
928 |
/* Want a backing file? There you go.*/
|
929 |
if (backing_file) {
|
930 |
ret = bdrv_change_backing_file(bs, backing_file, backing_format); |
931 |
if (ret < 0) { |
932 |
goto out;
|
933 |
} |
934 |
} |
935 |
|
936 |
/* And if we're supposed to preallocate metadata, do that now */
|
937 |
if (prealloc) {
|
938 |
ret = preallocate(bs); |
939 |
if (ret < 0) { |
940 |
goto out;
|
941 |
} |
942 |
} |
943 |
|
944 |
ret = 0;
|
945 |
out:
|
946 |
bdrv_delete(bs); |
947 |
return ret;
|
948 |
} |
949 |
|
950 |
static int qcow2_create(const char *filename, QEMUOptionParameter *options) |
951 |
{ |
952 |
const char *backing_file = NULL; |
953 |
const char *backing_fmt = NULL; |
954 |
uint64_t sectors = 0;
|
955 |
int flags = 0; |
956 |
size_t cluster_size = DEFAULT_CLUSTER_SIZE; |
957 |
int prealloc = 0; |
958 |
|
959 |
/* Read out options */
|
960 |
while (options && options->name) {
|
961 |
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
|
962 |
sectors = options->value.n / 512;
|
963 |
} else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) { |
964 |
backing_file = options->value.s; |
965 |
} else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) { |
966 |
backing_fmt = options->value.s; |
967 |
} else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) { |
968 |
flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0;
|
969 |
} else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { |
970 |
if (options->value.n) {
|
971 |
cluster_size = options->value.n; |
972 |
} |
973 |
} else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) { |
974 |
if (!options->value.s || !strcmp(options->value.s, "off")) { |
975 |
prealloc = 0;
|
976 |
} else if (!strcmp(options->value.s, "metadata")) { |
977 |
prealloc = 1;
|
978 |
} else {
|
979 |
fprintf(stderr, "Invalid preallocation mode: '%s'\n",
|
980 |
options->value.s); |
981 |
return -EINVAL;
|
982 |
} |
983 |
} |
984 |
options++; |
985 |
} |
986 |
|
987 |
if (backing_file && prealloc) {
|
988 |
fprintf(stderr, "Backing file and preallocation cannot be used at "
|
989 |
"the same time\n");
|
990 |
return -EINVAL;
|
991 |
} |
992 |
|
993 |
return qcow2_create2(filename, sectors, backing_file, backing_fmt, flags,
|
994 |
cluster_size, prealloc, options); |
995 |
} |
996 |
|
997 |
static int qcow2_make_empty(BlockDriverState *bs) |
998 |
{ |
999 |
#if 0
|
1000 |
/* XXX: not correct */
|
1001 |
BDRVQcowState *s = bs->opaque;
|
1002 |
uint32_t l1_length = s->l1_size * sizeof(uint64_t);
|
1003 |
int ret;
|
1004 |
|
1005 |
memset(s->l1_table, 0, l1_length);
|
1006 |
if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0)
|
1007 |
return -1;
|
1008 |
ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length);
|
1009 |
if (ret < 0)
|
1010 |
return ret;
|
1011 |
|
1012 |
l2_cache_reset(bs);
|
1013 |
#endif
|
1014 |
return 0; |
1015 |
} |
1016 |
|
1017 |
static coroutine_fn int qcow2_co_discard(BlockDriverState *bs, |
1018 |
int64_t sector_num, int nb_sectors)
|
1019 |
{ |
1020 |
int ret;
|
1021 |
BDRVQcowState *s = bs->opaque; |
1022 |
|
1023 |
qemu_co_mutex_lock(&s->lock); |
1024 |
ret = qcow2_discard_clusters(bs, sector_num << BDRV_SECTOR_BITS, |
1025 |
nb_sectors); |
1026 |
qemu_co_mutex_unlock(&s->lock); |
1027 |
return ret;
|
1028 |
} |
1029 |
|
1030 |
static int qcow2_truncate(BlockDriverState *bs, int64_t offset) |
1031 |
{ |
1032 |
BDRVQcowState *s = bs->opaque; |
1033 |
int ret, new_l1_size;
|
1034 |
|
1035 |
if (offset & 511) { |
1036 |
return -EINVAL;
|
1037 |
} |
1038 |
|
1039 |
/* cannot proceed if image has snapshots */
|
1040 |
if (s->nb_snapshots) {
|
1041 |
return -ENOTSUP;
|
1042 |
} |
1043 |
|
1044 |
/* shrinking is currently not supported */
|
1045 |
if (offset < bs->total_sectors * 512) { |
1046 |
return -ENOTSUP;
|
1047 |
} |
1048 |
|
1049 |
new_l1_size = size_to_l1(s, offset); |
1050 |
ret = qcow2_grow_l1_table(bs, new_l1_size, true);
|
1051 |
if (ret < 0) { |
1052 |
return ret;
|
1053 |
} |
1054 |
|
1055 |
/* write updated header.size */
|
1056 |
offset = cpu_to_be64(offset); |
1057 |
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size), |
1058 |
&offset, sizeof(uint64_t));
|
1059 |
if (ret < 0) { |
1060 |
return ret;
|
1061 |
} |
1062 |
|
1063 |
s->l1_vm_state_index = new_l1_size; |
1064 |
return 0; |
1065 |
} |
1066 |
|
1067 |
/* XXX: put compressed sectors first, then all the cluster aligned
|
1068 |
tables to avoid losing bytes in alignment */
|
1069 |
static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num, |
1070 |
const uint8_t *buf, int nb_sectors) |
1071 |
{ |
1072 |
BDRVQcowState *s = bs->opaque; |
1073 |
z_stream strm; |
1074 |
int ret, out_len;
|
1075 |
uint8_t *out_buf; |
1076 |
uint64_t cluster_offset; |
1077 |
|
1078 |
if (nb_sectors == 0) { |
1079 |
/* align end of file to a sector boundary to ease reading with
|
1080 |
sector based I/Os */
|
1081 |
cluster_offset = bdrv_getlength(bs->file); |
1082 |
cluster_offset = (cluster_offset + 511) & ~511; |
1083 |
bdrv_truncate(bs->file, cluster_offset); |
1084 |
return 0; |
1085 |
} |
1086 |
|
1087 |
if (nb_sectors != s->cluster_sectors)
|
1088 |
return -EINVAL;
|
1089 |
|
1090 |
out_buf = g_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); |
1091 |
|
1092 |
/* best compression, small window, no zlib header */
|
1093 |
memset(&strm, 0, sizeof(strm)); |
1094 |
ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, |
1095 |
Z_DEFLATED, -12,
|
1096 |
9, Z_DEFAULT_STRATEGY);
|
1097 |
if (ret != 0) { |
1098 |
ret = -EINVAL; |
1099 |
goto fail;
|
1100 |
} |
1101 |
|
1102 |
strm.avail_in = s->cluster_size; |
1103 |
strm.next_in = (uint8_t *)buf; |
1104 |
strm.avail_out = s->cluster_size; |
1105 |
strm.next_out = out_buf; |
1106 |
|
1107 |
ret = deflate(&strm, Z_FINISH); |
1108 |
if (ret != Z_STREAM_END && ret != Z_OK) {
|
1109 |
deflateEnd(&strm); |
1110 |
ret = -EINVAL; |
1111 |
goto fail;
|
1112 |
} |
1113 |
out_len = strm.next_out - out_buf; |
1114 |
|
1115 |
deflateEnd(&strm); |
1116 |
|
1117 |
if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
|
1118 |
/* could not compress: write normal cluster */
|
1119 |
ret = bdrv_write(bs, sector_num, buf, s->cluster_sectors); |
1120 |
if (ret < 0) { |
1121 |
goto fail;
|
1122 |
} |
1123 |
} else {
|
1124 |
cluster_offset = qcow2_alloc_compressed_cluster_offset(bs, |
1125 |
sector_num << 9, out_len);
|
1126 |
if (!cluster_offset) {
|
1127 |
ret = -EIO; |
1128 |
goto fail;
|
1129 |
} |
1130 |
cluster_offset &= s->cluster_offset_mask; |
1131 |
BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED); |
1132 |
ret = bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len); |
1133 |
if (ret < 0) { |
1134 |
goto fail;
|
1135 |
} |
1136 |
} |
1137 |
|
1138 |
ret = 0;
|
1139 |
fail:
|
1140 |
g_free(out_buf); |
1141 |
return ret;
|
1142 |
} |
1143 |
|
1144 |
static coroutine_fn int qcow2_co_flush_to_os(BlockDriverState *bs) |
1145 |
{ |
1146 |
BDRVQcowState *s = bs->opaque; |
1147 |
int ret;
|
1148 |
|
1149 |
qemu_co_mutex_lock(&s->lock); |
1150 |
ret = qcow2_cache_flush(bs, s->l2_table_cache); |
1151 |
if (ret < 0) { |
1152 |
qemu_co_mutex_unlock(&s->lock); |
1153 |
return ret;
|
1154 |
} |
1155 |
|
1156 |
ret = qcow2_cache_flush(bs, s->refcount_block_cache); |
1157 |
if (ret < 0) { |
1158 |
qemu_co_mutex_unlock(&s->lock); |
1159 |
return ret;
|
1160 |
} |
1161 |
qemu_co_mutex_unlock(&s->lock); |
1162 |
|
1163 |
return 0; |
1164 |
} |
1165 |
|
1166 |
static coroutine_fn int qcow2_co_flush_to_disk(BlockDriverState *bs) |
1167 |
{ |
1168 |
return bdrv_co_flush(bs->file);
|
1169 |
} |
1170 |
|
1171 |
static int64_t qcow2_vm_state_offset(BDRVQcowState *s)
|
1172 |
{ |
1173 |
return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
|
1174 |
} |
1175 |
|
1176 |
static int qcow2_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
1177 |
{ |
1178 |
BDRVQcowState *s = bs->opaque; |
1179 |
bdi->cluster_size = s->cluster_size; |
1180 |
bdi->vm_state_offset = qcow2_vm_state_offset(s); |
1181 |
return 0; |
1182 |
} |
1183 |
|
1184 |
|
1185 |
static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result) |
1186 |
{ |
1187 |
return qcow2_check_refcounts(bs, result);
|
1188 |
} |
1189 |
|
1190 |
#if 0
|
1191 |
static void dump_refcounts(BlockDriverState *bs)
|
1192 |
{
|
1193 |
BDRVQcowState *s = bs->opaque;
|
1194 |
int64_t nb_clusters, k, k1, size;
|
1195 |
int refcount;
|
1196 |
|
1197 |
size = bdrv_getlength(bs->file);
|
1198 |
nb_clusters = size_to_clusters(s, size);
|
1199 |
for(k = 0; k < nb_clusters;) {
|
1200 |
k1 = k;
|
1201 |
refcount = get_refcount(bs, k);
|
1202 |
k++;
|
1203 |
while (k < nb_clusters && get_refcount(bs, k) == refcount)
|
1204 |
k++;
|
1205 |
printf("%" PRId64 ": refcount=%d nb=%" PRId64 "\n", k, refcount,
|
1206 |
k - k1);
|
1207 |
}
|
1208 |
}
|
1209 |
#endif
|
1210 |
|
1211 |
static int qcow2_save_vmstate(BlockDriverState *bs, const uint8_t *buf, |
1212 |
int64_t pos, int size)
|
1213 |
{ |
1214 |
BDRVQcowState *s = bs->opaque; |
1215 |
int growable = bs->growable;
|
1216 |
int ret;
|
1217 |
|
1218 |
BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); |
1219 |
bs->growable = 1;
|
1220 |
ret = bdrv_pwrite(bs, qcow2_vm_state_offset(s) + pos, buf, size); |
1221 |
bs->growable = growable; |
1222 |
|
1223 |
return ret;
|
1224 |
} |
1225 |
|
1226 |
static int qcow2_load_vmstate(BlockDriverState *bs, uint8_t *buf, |
1227 |
int64_t pos, int size)
|
1228 |
{ |
1229 |
BDRVQcowState *s = bs->opaque; |
1230 |
int growable = bs->growable;
|
1231 |
int ret;
|
1232 |
|
1233 |
BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD); |
1234 |
bs->growable = 1;
|
1235 |
ret = bdrv_pread(bs, qcow2_vm_state_offset(s) + pos, buf, size); |
1236 |
bs->growable = growable; |
1237 |
|
1238 |
return ret;
|
1239 |
} |
1240 |
|
1241 |
static QEMUOptionParameter qcow2_create_options[] = {
|
1242 |
{ |
1243 |
.name = BLOCK_OPT_SIZE, |
1244 |
.type = OPT_SIZE, |
1245 |
.help = "Virtual disk size"
|
1246 |
}, |
1247 |
{ |
1248 |
.name = BLOCK_OPT_BACKING_FILE, |
1249 |
.type = OPT_STRING, |
1250 |
.help = "File name of a base image"
|
1251 |
}, |
1252 |
{ |
1253 |
.name = BLOCK_OPT_BACKING_FMT, |
1254 |
.type = OPT_STRING, |
1255 |
.help = "Image format of the base image"
|
1256 |
}, |
1257 |
{ |
1258 |
.name = BLOCK_OPT_ENCRYPT, |
1259 |
.type = OPT_FLAG, |
1260 |
.help = "Encrypt the image"
|
1261 |
}, |
1262 |
{ |
1263 |
.name = BLOCK_OPT_CLUSTER_SIZE, |
1264 |
.type = OPT_SIZE, |
1265 |
.help = "qcow2 cluster size",
|
1266 |
.value = { .n = DEFAULT_CLUSTER_SIZE }, |
1267 |
}, |
1268 |
{ |
1269 |
.name = BLOCK_OPT_PREALLOC, |
1270 |
.type = OPT_STRING, |
1271 |
.help = "Preallocation mode (allowed values: off, metadata)"
|
1272 |
}, |
1273 |
{ NULL }
|
1274 |
}; |
1275 |
|
1276 |
static BlockDriver bdrv_qcow2 = {
|
1277 |
.format_name = "qcow2",
|
1278 |
.instance_size = sizeof(BDRVQcowState),
|
1279 |
.bdrv_probe = qcow2_probe, |
1280 |
.bdrv_open = qcow2_open, |
1281 |
.bdrv_close = qcow2_close, |
1282 |
.bdrv_create = qcow2_create, |
1283 |
.bdrv_co_is_allocated = qcow2_co_is_allocated, |
1284 |
.bdrv_set_key = qcow2_set_key, |
1285 |
.bdrv_make_empty = qcow2_make_empty, |
1286 |
|
1287 |
.bdrv_co_readv = qcow2_co_readv, |
1288 |
.bdrv_co_writev = qcow2_co_writev, |
1289 |
.bdrv_co_flush_to_os = qcow2_co_flush_to_os, |
1290 |
.bdrv_co_flush_to_disk = qcow2_co_flush_to_disk, |
1291 |
|
1292 |
.bdrv_co_discard = qcow2_co_discard, |
1293 |
.bdrv_truncate = qcow2_truncate, |
1294 |
.bdrv_write_compressed = qcow2_write_compressed, |
1295 |
|
1296 |
.bdrv_snapshot_create = qcow2_snapshot_create, |
1297 |
.bdrv_snapshot_goto = qcow2_snapshot_goto, |
1298 |
.bdrv_snapshot_delete = qcow2_snapshot_delete, |
1299 |
.bdrv_snapshot_list = qcow2_snapshot_list, |
1300 |
.bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp, |
1301 |
.bdrv_get_info = qcow2_get_info, |
1302 |
|
1303 |
.bdrv_save_vmstate = qcow2_save_vmstate, |
1304 |
.bdrv_load_vmstate = qcow2_load_vmstate, |
1305 |
|
1306 |
.bdrv_change_backing_file = qcow2_change_backing_file, |
1307 |
|
1308 |
.bdrv_invalidate_cache = qcow2_invalidate_cache, |
1309 |
|
1310 |
.create_options = qcow2_create_options, |
1311 |
.bdrv_check = qcow2_check, |
1312 |
}; |
1313 |
|
1314 |
static void bdrv_qcow2_init(void) |
1315 |
{ |
1316 |
bdrv_register(&bdrv_qcow2); |
1317 |
} |
1318 |
|
1319 |
block_init(bdrv_qcow2_init); |