root / block / qcow2.c @ 6f6dc656
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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" |
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#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" |
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#include "block/qcow2.h" |
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#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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- 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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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 |
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|
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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; |
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|
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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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} |
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|
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|
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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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printf("attemting to read extended header in offset %lu\n", offset);
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#endif
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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; |
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} |
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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; |
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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); |
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break;
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default:
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/* unknown magic -- just skip it */
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offset = ((offset + ext.len + 7) & ~7); |
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break;
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} |
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} |
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|
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return 0; |
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} |
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|
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|
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static int qcow2_open(BlockDriverState *bs, int flags) |
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{ |
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BDRVQcowState *s = bs->opaque; |
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int len, i, ret = 0; |
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QCowHeader header; |
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uint64_t ext_end; |
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bool writethrough;
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|
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ret = bdrv_pread(bs->file, 0, &header, sizeof(header)); |
151 |
if (ret < 0) { |
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goto fail;
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} |
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be32_to_cpus(&header.magic); |
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be32_to_cpus(&header.version); |
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be64_to_cpus(&header.backing_file_offset); |
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be32_to_cpus(&header.backing_file_size); |
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be64_to_cpus(&header.size); |
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be32_to_cpus(&header.cluster_bits); |
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be32_to_cpus(&header.crypt_method); |
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be64_to_cpus(&header.l1_table_offset); |
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be32_to_cpus(&header.l1_size); |
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be64_to_cpus(&header.refcount_table_offset); |
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be32_to_cpus(&header.refcount_table_clusters); |
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be64_to_cpus(&header.snapshots_offset); |
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be32_to_cpus(&header.nb_snapshots); |
167 |
|
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if (header.magic != QCOW_MAGIC) {
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ret = -EINVAL; |
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goto fail;
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} |
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if (header.version != QCOW_VERSION) {
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char version[64]; |
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snprintf(version, sizeof(version), "QCOW version %d", header.version); |
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qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, |
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bs->device_name, "qcow2", version);
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ret = -ENOTSUP; |
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goto fail;
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} |
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if (header.cluster_bits < MIN_CLUSTER_BITS ||
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header.cluster_bits > MAX_CLUSTER_BITS) { |
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ret = -EINVAL; |
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goto fail;
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} |
185 |
if (header.crypt_method > QCOW_CRYPT_AES) {
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ret = -EINVAL; |
187 |
goto fail;
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} |
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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} |
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s->cluster_bits = header.cluster_bits; |
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s->cluster_size = 1 << s->cluster_bits;
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s->cluster_sectors = 1 << (s->cluster_bits - 9); |
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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)); |
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s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; |
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s->cluster_offset_mask = (1LL << s->csize_shift) - 1; |
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s->refcount_table_offset = header.refcount_table_offset; |
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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; |
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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); |
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/* the L1 table must contain at least enough entries to put
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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) { |
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s->l1_table = g_malloc0( |
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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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} |
227 |
for(i = 0;i < s->l1_size; i++) { |
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be64_to_cpus(&s->l1_table[i]); |
229 |
} |
230 |
} |
231 |
|
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/* 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, |
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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 |
|
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ret = qcow2_refcount_init(bs); |
245 |
if (ret != 0) { |
246 |
goto fail;
|
247 |
} |
248 |
|
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QLIST_INIT(&s->cluster_allocs); |
250 |
|
251 |
/* read qcow2 extensions */
|
252 |
if (header.backing_file_offset) {
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ext_end = header.backing_file_offset; |
254 |
} else {
|
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ext_end = s->cluster_size; |
256 |
} |
257 |
if (qcow2_read_extensions(bs, sizeof(header), ext_end)) { |
258 |
ret = -EINVAL; |
259 |
goto fail;
|
260 |
} |
261 |
|
262 |
/* read the backing file name */
|
263 |
if (header.backing_file_offset != 0) { |
264 |
len = header.backing_file_size; |
265 |
if (len > 1023) { |
266 |
len = 1023;
|
267 |
} |
268 |
ret = bdrv_pread(bs->file, header.backing_file_offset, |
269 |
bs->backing_file, len); |
270 |
if (ret < 0) { |
271 |
goto fail;
|
272 |
} |
273 |
bs->backing_file[len] = '\0';
|
274 |
} |
275 |
if (qcow2_read_snapshots(bs) < 0) { |
276 |
ret = -EINVAL; |
277 |
goto fail;
|
278 |
} |
279 |
|
280 |
/* Initialise locks */
|
281 |
qemu_co_mutex_init(&s->lock); |
282 |
|
283 |
#ifdef DEBUG_ALLOC
|
284 |
{ |
285 |
BdrvCheckResult result = {0};
|
286 |
qcow2_check_refcounts(bs, &result); |
287 |
} |
288 |
#endif
|
289 |
return ret;
|
290 |
|
291 |
fail:
|
292 |
qcow2_free_snapshots(bs); |
293 |
qcow2_refcount_close(bs); |
294 |
g_free(s->l1_table); |
295 |
if (s->l2_table_cache) {
|
296 |
qcow2_cache_destroy(bs, s->l2_table_cache); |
297 |
} |
298 |
g_free(s->cluster_cache); |
299 |
qemu_vfree(s->cluster_data); |
300 |
return ret;
|
301 |
} |
302 |
|
303 |
static int qcow2_set_key(BlockDriverState *bs, const char *key) |
304 |
{ |
305 |
BDRVQcowState *s = bs->opaque; |
306 |
uint8_t keybuf[16];
|
307 |
int len, i;
|
308 |
|
309 |
memset(keybuf, 0, 16); |
310 |
len = strlen(key); |
311 |
if (len > 16) |
312 |
len = 16;
|
313 |
/* XXX: we could compress the chars to 7 bits to increase
|
314 |
entropy */
|
315 |
for(i = 0;i < len;i++) { |
316 |
keybuf[i] = key[i]; |
317 |
} |
318 |
s->crypt_method = s->crypt_method_header; |
319 |
|
320 |
if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) |
321 |
return -1; |
322 |
if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) |
323 |
return -1; |
324 |
#if 0
|
325 |
/* test */
|
326 |
{
|
327 |
uint8_t in[16];
|
328 |
uint8_t out[16];
|
329 |
uint8_t tmp[16];
|
330 |
for(i=0;i<16;i++)
|
331 |
in[i] = i;
|
332 |
AES_encrypt(in, tmp, &s->aes_encrypt_key);
|
333 |
AES_decrypt(tmp, out, &s->aes_decrypt_key);
|
334 |
for(i = 0; i < 16; i++)
|
335 |
printf(" %02x", tmp[i]);
|
336 |
printf("\n");
|
337 |
for(i = 0; i < 16; i++)
|
338 |
printf(" %02x", out[i]);
|
339 |
printf("\n");
|
340 |
}
|
341 |
#endif
|
342 |
return 0; |
343 |
} |
344 |
|
345 |
static int qcow2_is_allocated(BlockDriverState *bs, int64_t sector_num, |
346 |
int nb_sectors, int *pnum) |
347 |
{ |
348 |
uint64_t cluster_offset; |
349 |
int ret;
|
350 |
|
351 |
*pnum = nb_sectors; |
352 |
/* FIXME We can get errors here, but the bdrv_is_allocated interface can't
|
353 |
* pass them on today */
|
354 |
ret = qcow2_get_cluster_offset(bs, sector_num << 9, pnum, &cluster_offset);
|
355 |
if (ret < 0) { |
356 |
*pnum = 0;
|
357 |
} |
358 |
|
359 |
return (cluster_offset != 0); |
360 |
} |
361 |
|
362 |
/* handle reading after the end of the backing file */
|
363 |
int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
|
364 |
int64_t sector_num, int nb_sectors)
|
365 |
{ |
366 |
int n1;
|
367 |
if ((sector_num + nb_sectors) <= bs->total_sectors)
|
368 |
return nb_sectors;
|
369 |
if (sector_num >= bs->total_sectors)
|
370 |
n1 = 0;
|
371 |
else
|
372 |
n1 = bs->total_sectors - sector_num; |
373 |
|
374 |
qemu_iovec_memset_skip(qiov, 0, 512 * (nb_sectors - n1), 512 * n1); |
375 |
|
376 |
return n1;
|
377 |
} |
378 |
|
379 |
static int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num, |
380 |
int remaining_sectors, QEMUIOVector *qiov)
|
381 |
{ |
382 |
BDRVQcowState *s = bs->opaque; |
383 |
int index_in_cluster, n1;
|
384 |
int ret;
|
385 |
int cur_nr_sectors; /* number of sectors in current iteration */ |
386 |
uint64_t cluster_offset = 0;
|
387 |
uint64_t bytes_done = 0;
|
388 |
QEMUIOVector hd_qiov; |
389 |
uint8_t *cluster_data = NULL;
|
390 |
|
391 |
qemu_iovec_init(&hd_qiov, qiov->niov); |
392 |
|
393 |
qemu_co_mutex_lock(&s->lock); |
394 |
|
395 |
while (remaining_sectors != 0) { |
396 |
|
397 |
/* prepare next request */
|
398 |
cur_nr_sectors = remaining_sectors; |
399 |
if (s->crypt_method) {
|
400 |
cur_nr_sectors = MIN(cur_nr_sectors, |
401 |
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); |
402 |
} |
403 |
|
404 |
ret = qcow2_get_cluster_offset(bs, sector_num << 9,
|
405 |
&cur_nr_sectors, &cluster_offset); |
406 |
if (ret < 0) { |
407 |
goto fail;
|
408 |
} |
409 |
|
410 |
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
411 |
|
412 |
qemu_iovec_reset(&hd_qiov); |
413 |
qemu_iovec_copy(&hd_qiov, qiov, bytes_done, |
414 |
cur_nr_sectors * 512);
|
415 |
|
416 |
if (!cluster_offset) {
|
417 |
|
418 |
if (bs->backing_hd) {
|
419 |
/* read from the base image */
|
420 |
n1 = qcow2_backing_read1(bs->backing_hd, &hd_qiov, |
421 |
sector_num, cur_nr_sectors); |
422 |
if (n1 > 0) { |
423 |
BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO); |
424 |
qemu_co_mutex_unlock(&s->lock); |
425 |
ret = bdrv_co_readv(bs->backing_hd, sector_num, |
426 |
n1, &hd_qiov); |
427 |
qemu_co_mutex_lock(&s->lock); |
428 |
if (ret < 0) { |
429 |
goto fail;
|
430 |
} |
431 |
} |
432 |
} else {
|
433 |
/* Note: in this case, no need to wait */
|
434 |
qemu_iovec_memset(&hd_qiov, 0, 512 * cur_nr_sectors); |
435 |
} |
436 |
} else if (cluster_offset & QCOW_OFLAG_COMPRESSED) { |
437 |
/* add AIO support for compressed blocks ? */
|
438 |
ret = qcow2_decompress_cluster(bs, cluster_offset); |
439 |
if (ret < 0) { |
440 |
goto fail;
|
441 |
} |
442 |
|
443 |
qemu_iovec_from_buffer(&hd_qiov, |
444 |
s->cluster_cache + index_in_cluster * 512,
|
445 |
512 * cur_nr_sectors);
|
446 |
} else {
|
447 |
if ((cluster_offset & 511) != 0) { |
448 |
ret = -EIO; |
449 |
goto fail;
|
450 |
} |
451 |
|
452 |
if (s->crypt_method) {
|
453 |
/*
|
454 |
* For encrypted images, read everything into a temporary
|
455 |
* contiguous buffer on which the AES functions can work.
|
456 |
*/
|
457 |
if (!cluster_data) {
|
458 |
cluster_data = |
459 |
qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); |
460 |
} |
461 |
|
462 |
assert(cur_nr_sectors <= |
463 |
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); |
464 |
qemu_iovec_reset(&hd_qiov); |
465 |
qemu_iovec_add(&hd_qiov, cluster_data, |
466 |
512 * cur_nr_sectors);
|
467 |
} |
468 |
|
469 |
BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); |
470 |
qemu_co_mutex_unlock(&s->lock); |
471 |
ret = bdrv_co_readv(bs->file, |
472 |
(cluster_offset >> 9) + index_in_cluster,
|
473 |
cur_nr_sectors, &hd_qiov); |
474 |
qemu_co_mutex_lock(&s->lock); |
475 |
if (ret < 0) { |
476 |
goto fail;
|
477 |
} |
478 |
if (s->crypt_method) {
|
479 |
qcow2_encrypt_sectors(s, sector_num, cluster_data, |
480 |
cluster_data, cur_nr_sectors, 0, &s->aes_decrypt_key);
|
481 |
qemu_iovec_reset(&hd_qiov); |
482 |
qemu_iovec_copy(&hd_qiov, qiov, bytes_done, |
483 |
cur_nr_sectors * 512);
|
484 |
qemu_iovec_from_buffer(&hd_qiov, cluster_data, |
485 |
512 * cur_nr_sectors);
|
486 |
} |
487 |
} |
488 |
|
489 |
remaining_sectors -= cur_nr_sectors; |
490 |
sector_num += cur_nr_sectors; |
491 |
bytes_done += cur_nr_sectors * 512;
|
492 |
} |
493 |
ret = 0;
|
494 |
|
495 |
fail:
|
496 |
qemu_co_mutex_unlock(&s->lock); |
497 |
|
498 |
qemu_iovec_destroy(&hd_qiov); |
499 |
qemu_vfree(cluster_data); |
500 |
|
501 |
return ret;
|
502 |
} |
503 |
|
504 |
static void run_dependent_requests(BDRVQcowState *s, QCowL2Meta *m) |
505 |
{ |
506 |
/* Take the request off the list of running requests */
|
507 |
if (m->nb_clusters != 0) { |
508 |
QLIST_REMOVE(m, next_in_flight); |
509 |
} |
510 |
|
511 |
/* Restart all dependent requests */
|
512 |
if (!qemu_co_queue_empty(&m->dependent_requests)) {
|
513 |
qemu_co_mutex_unlock(&s->lock); |
514 |
while(qemu_co_queue_next(&m->dependent_requests));
|
515 |
qemu_co_mutex_lock(&s->lock); |
516 |
} |
517 |
} |
518 |
|
519 |
static int qcow2_co_writev(BlockDriverState *bs, |
520 |
int64_t sector_num, |
521 |
int remaining_sectors,
|
522 |
QEMUIOVector *qiov) |
523 |
{ |
524 |
BDRVQcowState *s = bs->opaque; |
525 |
int index_in_cluster;
|
526 |
int n_end;
|
527 |
int ret;
|
528 |
int cur_nr_sectors; /* number of sectors in current iteration */ |
529 |
uint64_t cluster_offset; |
530 |
QEMUIOVector hd_qiov; |
531 |
uint64_t bytes_done = 0;
|
532 |
uint8_t *cluster_data = NULL;
|
533 |
QCowL2Meta l2meta = { |
534 |
.nb_clusters = 0,
|
535 |
}; |
536 |
|
537 |
qemu_co_queue_init(&l2meta.dependent_requests); |
538 |
|
539 |
qemu_iovec_init(&hd_qiov, qiov->niov); |
540 |
|
541 |
s->cluster_cache_offset = -1; /* disable compressed cache */ |
542 |
|
543 |
qemu_co_mutex_lock(&s->lock); |
544 |
|
545 |
while (remaining_sectors != 0) { |
546 |
|
547 |
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
548 |
n_end = index_in_cluster + remaining_sectors; |
549 |
if (s->crypt_method &&
|
550 |
n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) { |
551 |
n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; |
552 |
} |
553 |
|
554 |
ret = qcow2_alloc_cluster_offset(bs, sector_num << 9,
|
555 |
index_in_cluster, n_end, &cur_nr_sectors, &l2meta); |
556 |
if (ret < 0) { |
557 |
goto fail;
|
558 |
} |
559 |
|
560 |
cluster_offset = l2meta.cluster_offset; |
561 |
assert((cluster_offset & 511) == 0); |
562 |
|
563 |
qemu_iovec_reset(&hd_qiov); |
564 |
qemu_iovec_copy(&hd_qiov, qiov, bytes_done, |
565 |
cur_nr_sectors * 512);
|
566 |
|
567 |
if (s->crypt_method) {
|
568 |
if (!cluster_data) {
|
569 |
cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * |
570 |
s->cluster_size); |
571 |
} |
572 |
|
573 |
assert(hd_qiov.size <= |
574 |
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); |
575 |
qemu_iovec_to_buffer(&hd_qiov, cluster_data); |
576 |
|
577 |
qcow2_encrypt_sectors(s, sector_num, cluster_data, |
578 |
cluster_data, cur_nr_sectors, 1, &s->aes_encrypt_key);
|
579 |
|
580 |
qemu_iovec_reset(&hd_qiov); |
581 |
qemu_iovec_add(&hd_qiov, cluster_data, |
582 |
cur_nr_sectors * 512);
|
583 |
} |
584 |
|
585 |
BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); |
586 |
qemu_co_mutex_unlock(&s->lock); |
587 |
ret = bdrv_co_writev(bs->file, |
588 |
(cluster_offset >> 9) + index_in_cluster,
|
589 |
cur_nr_sectors, &hd_qiov); |
590 |
qemu_co_mutex_lock(&s->lock); |
591 |
if (ret < 0) { |
592 |
goto fail;
|
593 |
} |
594 |
|
595 |
ret = qcow2_alloc_cluster_link_l2(bs, &l2meta); |
596 |
if (ret < 0) { |
597 |
goto fail;
|
598 |
} |
599 |
|
600 |
run_dependent_requests(s, &l2meta); |
601 |
|
602 |
remaining_sectors -= cur_nr_sectors; |
603 |
sector_num += cur_nr_sectors; |
604 |
bytes_done += cur_nr_sectors * 512;
|
605 |
} |
606 |
ret = 0;
|
607 |
|
608 |
fail:
|
609 |
run_dependent_requests(s, &l2meta); |
610 |
|
611 |
qemu_co_mutex_unlock(&s->lock); |
612 |
|
613 |
qemu_iovec_destroy(&hd_qiov); |
614 |
qemu_vfree(cluster_data); |
615 |
|
616 |
return ret;
|
617 |
} |
618 |
|
619 |
static void qcow2_close(BlockDriverState *bs) |
620 |
{ |
621 |
BDRVQcowState *s = bs->opaque; |
622 |
g_free(s->l1_table); |
623 |
|
624 |
qcow2_cache_flush(bs, s->l2_table_cache); |
625 |
qcow2_cache_flush(bs, s->refcount_block_cache); |
626 |
|
627 |
qcow2_cache_destroy(bs, s->l2_table_cache); |
628 |
qcow2_cache_destroy(bs, s->refcount_block_cache); |
629 |
|
630 |
g_free(s->cluster_cache); |
631 |
qemu_vfree(s->cluster_data); |
632 |
qcow2_refcount_close(bs); |
633 |
} |
634 |
|
635 |
/*
|
636 |
* Updates the variable length parts of the qcow2 header, i.e. the backing file
|
637 |
* name and all extensions. qcow2 was not designed to allow such changes, so if
|
638 |
* we run out of space (we can only use the first cluster) this function may
|
639 |
* fail.
|
640 |
*
|
641 |
* Returns 0 on success, -errno in error cases.
|
642 |
*/
|
643 |
static int qcow2_update_ext_header(BlockDriverState *bs, |
644 |
const char *backing_file, const char *backing_fmt) |
645 |
{ |
646 |
size_t backing_file_len = 0;
|
647 |
size_t backing_fmt_len = 0;
|
648 |
BDRVQcowState *s = bs->opaque; |
649 |
QCowExtension ext_backing_fmt = {0, 0}; |
650 |
int ret;
|
651 |
|
652 |
/* Backing file format doesn't make sense without a backing file */
|
653 |
if (backing_fmt && !backing_file) {
|
654 |
return -EINVAL;
|
655 |
} |
656 |
|
657 |
/* Prepare the backing file format extension if needed */
|
658 |
if (backing_fmt) {
|
659 |
ext_backing_fmt.len = cpu_to_be32(strlen(backing_fmt)); |
660 |
ext_backing_fmt.magic = cpu_to_be32(QCOW2_EXT_MAGIC_BACKING_FORMAT); |
661 |
backing_fmt_len = ((sizeof(ext_backing_fmt)
|
662 |
+ strlen(backing_fmt) + 7) & ~7); |
663 |
} |
664 |
|
665 |
/* Check if we can fit the new header into the first cluster */
|
666 |
if (backing_file) {
|
667 |
backing_file_len = strlen(backing_file); |
668 |
} |
669 |
|
670 |
size_t header_size = sizeof(QCowHeader) + backing_file_len
|
671 |
+ backing_fmt_len; |
672 |
|
673 |
if (header_size > s->cluster_size) {
|
674 |
return -ENOSPC;
|
675 |
} |
676 |
|
677 |
/* Rewrite backing file name and qcow2 extensions */
|
678 |
size_t ext_size = header_size - sizeof(QCowHeader);
|
679 |
uint8_t buf[ext_size]; |
680 |
size_t offset = 0;
|
681 |
size_t backing_file_offset = 0;
|
682 |
|
683 |
if (backing_file) {
|
684 |
if (backing_fmt) {
|
685 |
int padding = backing_fmt_len -
|
686 |
(sizeof(ext_backing_fmt) + strlen(backing_fmt));
|
687 |
|
688 |
memcpy(buf + offset, &ext_backing_fmt, sizeof(ext_backing_fmt));
|
689 |
offset += sizeof(ext_backing_fmt);
|
690 |
|
691 |
memcpy(buf + offset, backing_fmt, strlen(backing_fmt)); |
692 |
offset += strlen(backing_fmt); |
693 |
|
694 |
memset(buf + offset, 0, padding);
|
695 |
offset += padding; |
696 |
} |
697 |
|
698 |
memcpy(buf + offset, backing_file, backing_file_len); |
699 |
backing_file_offset = sizeof(QCowHeader) + offset;
|
700 |
} |
701 |
|
702 |
ret = bdrv_pwrite_sync(bs->file, sizeof(QCowHeader), buf, ext_size);
|
703 |
if (ret < 0) { |
704 |
goto fail;
|
705 |
} |
706 |
|
707 |
/* Update header fields */
|
708 |
uint64_t be_backing_file_offset = cpu_to_be64(backing_file_offset); |
709 |
uint32_t be_backing_file_size = cpu_to_be32(backing_file_len); |
710 |
|
711 |
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, backing_file_offset), |
712 |
&be_backing_file_offset, sizeof(uint64_t));
|
713 |
if (ret < 0) { |
714 |
goto fail;
|
715 |
} |
716 |
|
717 |
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, backing_file_size), |
718 |
&be_backing_file_size, sizeof(uint32_t));
|
719 |
if (ret < 0) { |
720 |
goto fail;
|
721 |
} |
722 |
|
723 |
ret = 0;
|
724 |
fail:
|
725 |
return ret;
|
726 |
} |
727 |
|
728 |
static int qcow2_change_backing_file(BlockDriverState *bs, |
729 |
const char *backing_file, const char *backing_fmt) |
730 |
{ |
731 |
return qcow2_update_ext_header(bs, backing_file, backing_fmt);
|
732 |
} |
733 |
|
734 |
static int preallocate(BlockDriverState *bs) |
735 |
{ |
736 |
uint64_t nb_sectors; |
737 |
uint64_t offset; |
738 |
int num;
|
739 |
int ret;
|
740 |
QCowL2Meta meta; |
741 |
|
742 |
nb_sectors = bdrv_getlength(bs) >> 9;
|
743 |
offset = 0;
|
744 |
qemu_co_queue_init(&meta.dependent_requests); |
745 |
meta.cluster_offset = 0;
|
746 |
|
747 |
while (nb_sectors) {
|
748 |
num = MIN(nb_sectors, INT_MAX >> 9);
|
749 |
ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num, &meta);
|
750 |
if (ret < 0) { |
751 |
return ret;
|
752 |
} |
753 |
|
754 |
ret = qcow2_alloc_cluster_link_l2(bs, &meta); |
755 |
if (ret < 0) { |
756 |
qcow2_free_any_clusters(bs, meta.cluster_offset, meta.nb_clusters); |
757 |
return ret;
|
758 |
} |
759 |
|
760 |
/* There are no dependent requests, but we need to remove our request
|
761 |
* from the list of in-flight requests */
|
762 |
run_dependent_requests(bs->opaque, &meta); |
763 |
|
764 |
/* TODO Preallocate data if requested */
|
765 |
|
766 |
nb_sectors -= num; |
767 |
offset += num << 9;
|
768 |
} |
769 |
|
770 |
/*
|
771 |
* It is expected that the image file is large enough to actually contain
|
772 |
* all of the allocated clusters (otherwise we get failing reads after
|
773 |
* EOF). Extend the image to the last allocated sector.
|
774 |
*/
|
775 |
if (meta.cluster_offset != 0) { |
776 |
uint8_t buf[512];
|
777 |
memset(buf, 0, 512); |
778 |
ret = bdrv_write(bs->file, (meta.cluster_offset >> 9) + num - 1, buf, 1); |
779 |
if (ret < 0) { |
780 |
return ret;
|
781 |
} |
782 |
} |
783 |
|
784 |
return 0; |
785 |
} |
786 |
|
787 |
static int qcow2_create2(const char *filename, int64_t total_size, |
788 |
const char *backing_file, const char *backing_format, |
789 |
int flags, size_t cluster_size, int prealloc, |
790 |
QEMUOptionParameter *options) |
791 |
{ |
792 |
/* Calulate cluster_bits */
|
793 |
int cluster_bits;
|
794 |
cluster_bits = ffs(cluster_size) - 1;
|
795 |
if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS ||
|
796 |
(1 << cluster_bits) != cluster_size)
|
797 |
{ |
798 |
error_report( |
799 |
"Cluster size must be a power of two between %d and %dk",
|
800 |
1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10)); |
801 |
return -EINVAL;
|
802 |
} |
803 |
|
804 |
/*
|
805 |
* Open the image file and write a minimal qcow2 header.
|
806 |
*
|
807 |
* We keep things simple and start with a zero-sized image. We also
|
808 |
* do without refcount blocks or a L1 table for now. We'll fix the
|
809 |
* inconsistency later.
|
810 |
*
|
811 |
* We do need a refcount table because growing the refcount table means
|
812 |
* allocating two new refcount blocks - the seconds of which would be at
|
813 |
* 2 GB for 64k clusters, and we don't want to have a 2 GB initial file
|
814 |
* size for any qcow2 image.
|
815 |
*/
|
816 |
BlockDriverState* bs; |
817 |
QCowHeader header; |
818 |
uint8_t* refcount_table; |
819 |
int ret;
|
820 |
|
821 |
ret = bdrv_create_file(filename, options); |
822 |
if (ret < 0) { |
823 |
return ret;
|
824 |
} |
825 |
|
826 |
ret = bdrv_file_open(&bs, filename, BDRV_O_RDWR); |
827 |
if (ret < 0) { |
828 |
return ret;
|
829 |
} |
830 |
|
831 |
/* Write the header */
|
832 |
memset(&header, 0, sizeof(header)); |
833 |
header.magic = cpu_to_be32(QCOW_MAGIC); |
834 |
header.version = cpu_to_be32(QCOW_VERSION); |
835 |
header.cluster_bits = cpu_to_be32(cluster_bits); |
836 |
header.size = cpu_to_be64(0);
|
837 |
header.l1_table_offset = cpu_to_be64(0);
|
838 |
header.l1_size = cpu_to_be32(0);
|
839 |
header.refcount_table_offset = cpu_to_be64(cluster_size); |
840 |
header.refcount_table_clusters = cpu_to_be32(1);
|
841 |
|
842 |
if (flags & BLOCK_FLAG_ENCRYPT) {
|
843 |
header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); |
844 |
} else {
|
845 |
header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); |
846 |
} |
847 |
|
848 |
ret = bdrv_pwrite(bs, 0, &header, sizeof(header)); |
849 |
if (ret < 0) { |
850 |
goto out;
|
851 |
} |
852 |
|
853 |
/* Write an empty refcount table */
|
854 |
refcount_table = g_malloc0(cluster_size); |
855 |
ret = bdrv_pwrite(bs, cluster_size, refcount_table, cluster_size); |
856 |
g_free(refcount_table); |
857 |
|
858 |
if (ret < 0) { |
859 |
goto out;
|
860 |
} |
861 |
|
862 |
bdrv_close(bs); |
863 |
|
864 |
/*
|
865 |
* And now open the image and make it consistent first (i.e. increase the
|
866 |
* refcount of the cluster that is occupied by the header and the refcount
|
867 |
* table)
|
868 |
*/
|
869 |
BlockDriver* drv = bdrv_find_format("qcow2");
|
870 |
assert(drv != NULL);
|
871 |
ret = bdrv_open(bs, filename, |
872 |
BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv); |
873 |
if (ret < 0) { |
874 |
goto out;
|
875 |
} |
876 |
|
877 |
ret = qcow2_alloc_clusters(bs, 2 * cluster_size);
|
878 |
if (ret < 0) { |
879 |
goto out;
|
880 |
|
881 |
} else if (ret != 0) { |
882 |
error_report("Huh, first cluster in empty image is already in use?");
|
883 |
abort(); |
884 |
} |
885 |
|
886 |
/* Okay, now that we have a valid image, let's give it the right size */
|
887 |
ret = bdrv_truncate(bs, total_size * BDRV_SECTOR_SIZE); |
888 |
if (ret < 0) { |
889 |
goto out;
|
890 |
} |
891 |
|
892 |
/* Want a backing file? There you go.*/
|
893 |
if (backing_file) {
|
894 |
ret = bdrv_change_backing_file(bs, backing_file, backing_format); |
895 |
if (ret < 0) { |
896 |
goto out;
|
897 |
} |
898 |
} |
899 |
|
900 |
/* And if we're supposed to preallocate metadata, do that now */
|
901 |
if (prealloc) {
|
902 |
ret = preallocate(bs); |
903 |
if (ret < 0) { |
904 |
goto out;
|
905 |
} |
906 |
} |
907 |
|
908 |
ret = 0;
|
909 |
out:
|
910 |
bdrv_delete(bs); |
911 |
return ret;
|
912 |
} |
913 |
|
914 |
static int qcow2_create(const char *filename, QEMUOptionParameter *options) |
915 |
{ |
916 |
const char *backing_file = NULL; |
917 |
const char *backing_fmt = NULL; |
918 |
uint64_t sectors = 0;
|
919 |
int flags = 0; |
920 |
size_t cluster_size = DEFAULT_CLUSTER_SIZE; |
921 |
int prealloc = 0; |
922 |
|
923 |
/* Read out options */
|
924 |
while (options && options->name) {
|
925 |
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
|
926 |
sectors = options->value.n / 512;
|
927 |
} else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) { |
928 |
backing_file = options->value.s; |
929 |
} else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) { |
930 |
backing_fmt = options->value.s; |
931 |
} else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) { |
932 |
flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0;
|
933 |
} else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { |
934 |
if (options->value.n) {
|
935 |
cluster_size = options->value.n; |
936 |
} |
937 |
} else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) { |
938 |
if (!options->value.s || !strcmp(options->value.s, "off")) { |
939 |
prealloc = 0;
|
940 |
} else if (!strcmp(options->value.s, "metadata")) { |
941 |
prealloc = 1;
|
942 |
} else {
|
943 |
fprintf(stderr, "Invalid preallocation mode: '%s'\n",
|
944 |
options->value.s); |
945 |
return -EINVAL;
|
946 |
} |
947 |
} |
948 |
options++; |
949 |
} |
950 |
|
951 |
if (backing_file && prealloc) {
|
952 |
fprintf(stderr, "Backing file and preallocation cannot be used at "
|
953 |
"the same time\n");
|
954 |
return -EINVAL;
|
955 |
} |
956 |
|
957 |
return qcow2_create2(filename, sectors, backing_file, backing_fmt, flags,
|
958 |
cluster_size, prealloc, options); |
959 |
} |
960 |
|
961 |
static int qcow2_make_empty(BlockDriverState *bs) |
962 |
{ |
963 |
#if 0
|
964 |
/* XXX: not correct */
|
965 |
BDRVQcowState *s = bs->opaque;
|
966 |
uint32_t l1_length = s->l1_size * sizeof(uint64_t);
|
967 |
int ret;
|
968 |
|
969 |
memset(s->l1_table, 0, l1_length);
|
970 |
if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0)
|
971 |
return -1;
|
972 |
ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length);
|
973 |
if (ret < 0)
|
974 |
return ret;
|
975 |
|
976 |
l2_cache_reset(bs);
|
977 |
#endif
|
978 |
return 0; |
979 |
} |
980 |
|
981 |
static int qcow2_discard(BlockDriverState *bs, int64_t sector_num, |
982 |
int nb_sectors)
|
983 |
{ |
984 |
return qcow2_discard_clusters(bs, sector_num << BDRV_SECTOR_BITS,
|
985 |
nb_sectors); |
986 |
} |
987 |
|
988 |
static int qcow2_truncate(BlockDriverState *bs, int64_t offset) |
989 |
{ |
990 |
BDRVQcowState *s = bs->opaque; |
991 |
int ret, new_l1_size;
|
992 |
|
993 |
if (offset & 511) { |
994 |
return -EINVAL;
|
995 |
} |
996 |
|
997 |
/* cannot proceed if image has snapshots */
|
998 |
if (s->nb_snapshots) {
|
999 |
return -ENOTSUP;
|
1000 |
} |
1001 |
|
1002 |
/* shrinking is currently not supported */
|
1003 |
if (offset < bs->total_sectors * 512) { |
1004 |
return -ENOTSUP;
|
1005 |
} |
1006 |
|
1007 |
new_l1_size = size_to_l1(s, offset); |
1008 |
ret = qcow2_grow_l1_table(bs, new_l1_size, true);
|
1009 |
if (ret < 0) { |
1010 |
return ret;
|
1011 |
} |
1012 |
|
1013 |
/* write updated header.size */
|
1014 |
offset = cpu_to_be64(offset); |
1015 |
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size), |
1016 |
&offset, sizeof(uint64_t));
|
1017 |
if (ret < 0) { |
1018 |
return ret;
|
1019 |
} |
1020 |
|
1021 |
s->l1_vm_state_index = new_l1_size; |
1022 |
return 0; |
1023 |
} |
1024 |
|
1025 |
/* XXX: put compressed sectors first, then all the cluster aligned
|
1026 |
tables to avoid losing bytes in alignment */
|
1027 |
static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num, |
1028 |
const uint8_t *buf, int nb_sectors) |
1029 |
{ |
1030 |
BDRVQcowState *s = bs->opaque; |
1031 |
z_stream strm; |
1032 |
int ret, out_len;
|
1033 |
uint8_t *out_buf; |
1034 |
uint64_t cluster_offset; |
1035 |
|
1036 |
if (nb_sectors == 0) { |
1037 |
/* align end of file to a sector boundary to ease reading with
|
1038 |
sector based I/Os */
|
1039 |
cluster_offset = bdrv_getlength(bs->file); |
1040 |
cluster_offset = (cluster_offset + 511) & ~511; |
1041 |
bdrv_truncate(bs->file, cluster_offset); |
1042 |
return 0; |
1043 |
} |
1044 |
|
1045 |
if (nb_sectors != s->cluster_sectors)
|
1046 |
return -EINVAL;
|
1047 |
|
1048 |
out_buf = g_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); |
1049 |
|
1050 |
/* best compression, small window, no zlib header */
|
1051 |
memset(&strm, 0, sizeof(strm)); |
1052 |
ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, |
1053 |
Z_DEFLATED, -12,
|
1054 |
9, Z_DEFAULT_STRATEGY);
|
1055 |
if (ret != 0) { |
1056 |
g_free(out_buf); |
1057 |
return -1; |
1058 |
} |
1059 |
|
1060 |
strm.avail_in = s->cluster_size; |
1061 |
strm.next_in = (uint8_t *)buf; |
1062 |
strm.avail_out = s->cluster_size; |
1063 |
strm.next_out = out_buf; |
1064 |
|
1065 |
ret = deflate(&strm, Z_FINISH); |
1066 |
if (ret != Z_STREAM_END && ret != Z_OK) {
|
1067 |
g_free(out_buf); |
1068 |
deflateEnd(&strm); |
1069 |
return -1; |
1070 |
} |
1071 |
out_len = strm.next_out - out_buf; |
1072 |
|
1073 |
deflateEnd(&strm); |
1074 |
|
1075 |
if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
|
1076 |
/* could not compress: write normal cluster */
|
1077 |
bdrv_write(bs, sector_num, buf, s->cluster_sectors); |
1078 |
} else {
|
1079 |
cluster_offset = qcow2_alloc_compressed_cluster_offset(bs, |
1080 |
sector_num << 9, out_len);
|
1081 |
if (!cluster_offset)
|
1082 |
return -1; |
1083 |
cluster_offset &= s->cluster_offset_mask; |
1084 |
BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED); |
1085 |
if (bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len) != out_len) {
|
1086 |
g_free(out_buf); |
1087 |
return -1; |
1088 |
} |
1089 |
} |
1090 |
|
1091 |
g_free(out_buf); |
1092 |
return 0; |
1093 |
} |
1094 |
|
1095 |
static BlockDriverAIOCB *qcow2_aio_flush(BlockDriverState *bs,
|
1096 |
BlockDriverCompletionFunc *cb, |
1097 |
void *opaque)
|
1098 |
{ |
1099 |
BDRVQcowState *s = bs->opaque; |
1100 |
int ret;
|
1101 |
|
1102 |
ret = qcow2_cache_flush(bs, s->l2_table_cache); |
1103 |
if (ret < 0) { |
1104 |
return NULL; |
1105 |
} |
1106 |
|
1107 |
ret = qcow2_cache_flush(bs, s->refcount_block_cache); |
1108 |
if (ret < 0) { |
1109 |
return NULL; |
1110 |
} |
1111 |
|
1112 |
return bdrv_aio_flush(bs->file, cb, opaque);
|
1113 |
} |
1114 |
|
1115 |
static int64_t qcow2_vm_state_offset(BDRVQcowState *s)
|
1116 |
{ |
1117 |
return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
|
1118 |
} |
1119 |
|
1120 |
static int qcow2_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
1121 |
{ |
1122 |
BDRVQcowState *s = bs->opaque; |
1123 |
bdi->cluster_size = s->cluster_size; |
1124 |
bdi->vm_state_offset = qcow2_vm_state_offset(s); |
1125 |
return 0; |
1126 |
} |
1127 |
|
1128 |
|
1129 |
static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result) |
1130 |
{ |
1131 |
return qcow2_check_refcounts(bs, result);
|
1132 |
} |
1133 |
|
1134 |
#if 0
|
1135 |
static void dump_refcounts(BlockDriverState *bs)
|
1136 |
{
|
1137 |
BDRVQcowState *s = bs->opaque;
|
1138 |
int64_t nb_clusters, k, k1, size;
|
1139 |
int refcount;
|
1140 |
|
1141 |
size = bdrv_getlength(bs->file);
|
1142 |
nb_clusters = size_to_clusters(s, size);
|
1143 |
for(k = 0; k < nb_clusters;) {
|
1144 |
k1 = k;
|
1145 |
refcount = get_refcount(bs, k);
|
1146 |
k++;
|
1147 |
while (k < nb_clusters && get_refcount(bs, k) == refcount)
|
1148 |
k++;
|
1149 |
printf("%" PRId64 ": refcount=%d nb=%" PRId64 "\n", k, refcount,
|
1150 |
k - k1);
|
1151 |
}
|
1152 |
}
|
1153 |
#endif
|
1154 |
|
1155 |
static int qcow2_save_vmstate(BlockDriverState *bs, const uint8_t *buf, |
1156 |
int64_t pos, int size)
|
1157 |
{ |
1158 |
BDRVQcowState *s = bs->opaque; |
1159 |
int growable = bs->growable;
|
1160 |
int ret;
|
1161 |
|
1162 |
BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); |
1163 |
bs->growable = 1;
|
1164 |
ret = bdrv_pwrite(bs, qcow2_vm_state_offset(s) + pos, buf, size); |
1165 |
bs->growable = growable; |
1166 |
|
1167 |
return ret;
|
1168 |
} |
1169 |
|
1170 |
static int qcow2_load_vmstate(BlockDriverState *bs, uint8_t *buf, |
1171 |
int64_t pos, int size)
|
1172 |
{ |
1173 |
BDRVQcowState *s = bs->opaque; |
1174 |
int growable = bs->growable;
|
1175 |
int ret;
|
1176 |
|
1177 |
BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD); |
1178 |
bs->growable = 1;
|
1179 |
ret = bdrv_pread(bs, qcow2_vm_state_offset(s) + pos, buf, size); |
1180 |
bs->growable = growable; |
1181 |
|
1182 |
return ret;
|
1183 |
} |
1184 |
|
1185 |
static QEMUOptionParameter qcow2_create_options[] = {
|
1186 |
{ |
1187 |
.name = BLOCK_OPT_SIZE, |
1188 |
.type = OPT_SIZE, |
1189 |
.help = "Virtual disk size"
|
1190 |
}, |
1191 |
{ |
1192 |
.name = BLOCK_OPT_BACKING_FILE, |
1193 |
.type = OPT_STRING, |
1194 |
.help = "File name of a base image"
|
1195 |
}, |
1196 |
{ |
1197 |
.name = BLOCK_OPT_BACKING_FMT, |
1198 |
.type = OPT_STRING, |
1199 |
.help = "Image format of the base image"
|
1200 |
}, |
1201 |
{ |
1202 |
.name = BLOCK_OPT_ENCRYPT, |
1203 |
.type = OPT_FLAG, |
1204 |
.help = "Encrypt the image"
|
1205 |
}, |
1206 |
{ |
1207 |
.name = BLOCK_OPT_CLUSTER_SIZE, |
1208 |
.type = OPT_SIZE, |
1209 |
.help = "qcow2 cluster size",
|
1210 |
.value = { .n = DEFAULT_CLUSTER_SIZE }, |
1211 |
}, |
1212 |
{ |
1213 |
.name = BLOCK_OPT_PREALLOC, |
1214 |
.type = OPT_STRING, |
1215 |
.help = "Preallocation mode (allowed values: off, metadata)"
|
1216 |
}, |
1217 |
{ NULL }
|
1218 |
}; |
1219 |
|
1220 |
static BlockDriver bdrv_qcow2 = {
|
1221 |
.format_name = "qcow2",
|
1222 |
.instance_size = sizeof(BDRVQcowState),
|
1223 |
.bdrv_probe = qcow2_probe, |
1224 |
.bdrv_open = qcow2_open, |
1225 |
.bdrv_close = qcow2_close, |
1226 |
.bdrv_create = qcow2_create, |
1227 |
.bdrv_is_allocated = qcow2_is_allocated, |
1228 |
.bdrv_set_key = qcow2_set_key, |
1229 |
.bdrv_make_empty = qcow2_make_empty, |
1230 |
|
1231 |
.bdrv_co_readv = qcow2_co_readv, |
1232 |
.bdrv_co_writev = qcow2_co_writev, |
1233 |
.bdrv_aio_flush = qcow2_aio_flush, |
1234 |
|
1235 |
.bdrv_discard = qcow2_discard, |
1236 |
.bdrv_truncate = qcow2_truncate, |
1237 |
.bdrv_write_compressed = qcow2_write_compressed, |
1238 |
|
1239 |
.bdrv_snapshot_create = qcow2_snapshot_create, |
1240 |
.bdrv_snapshot_goto = qcow2_snapshot_goto, |
1241 |
.bdrv_snapshot_delete = qcow2_snapshot_delete, |
1242 |
.bdrv_snapshot_list = qcow2_snapshot_list, |
1243 |
.bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp, |
1244 |
.bdrv_get_info = qcow2_get_info, |
1245 |
|
1246 |
.bdrv_save_vmstate = qcow2_save_vmstate, |
1247 |
.bdrv_load_vmstate = qcow2_load_vmstate, |
1248 |
|
1249 |
.bdrv_change_backing_file = qcow2_change_backing_file, |
1250 |
|
1251 |
.create_options = qcow2_create_options, |
1252 |
.bdrv_check = qcow2_check, |
1253 |
}; |
1254 |
|
1255 |
static void bdrv_qcow2_init(void) |
1256 |
{ |
1257 |
bdrv_register(&bdrv_qcow2); |
1258 |
} |
1259 |
|
1260 |
block_init(bdrv_qcow2_init); |