In addition this adds missing braces to the function to be consistent with the coding style. Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
1337 lines
39 KiB
C
1337 lines
39 KiB
C
/*
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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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/*
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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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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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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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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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* 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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#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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#ifdef DEBUG_EXT
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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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return 0;
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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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ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
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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);
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if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION) {
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ret = -EINVAL;
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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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}
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if (header.crypt_method > QCOW_CRYPT_AES) {
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ret = -EINVAL;
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goto fail;
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}
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s->crypt_method_header = header.crypt_method;
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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 */
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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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s->snapshots_offset = header.snapshots_offset;
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s->nb_snapshots = header.nb_snapshots;
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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;
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goto fail;
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}
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s->l1_table_offset = header.l1_table_offset;
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if (s->l1_size > 0) {
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s->l1_table = qemu_mallocz(
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align_offset(s->l1_size * sizeof(uint64_t), 512));
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ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table,
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s->l1_size * sizeof(uint64_t));
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if (ret < 0) {
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goto fail;
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}
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for(i = 0;i < s->l1_size; i++) {
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be64_to_cpus(&s->l1_table[i]);
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}
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}
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/* alloc L2 cache */
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s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
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s->cluster_cache = qemu_malloc(s->cluster_size);
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/* one more sector for decompressed data alignment */
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s->cluster_data = qemu_malloc(QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size
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+ 512);
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s->cluster_cache_offset = -1;
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ret = qcow2_refcount_init(bs);
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if (ret != 0) {
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goto fail;
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}
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QLIST_INIT(&s->cluster_allocs);
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/* read qcow2 extensions */
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if (header.backing_file_offset) {
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ext_end = header.backing_file_offset;
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} else {
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ext_end = s->cluster_size;
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}
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if (qcow2_read_extensions(bs, sizeof(header), ext_end)) {
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ret = -EINVAL;
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goto fail;
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}
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/* read the backing file name */
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if (header.backing_file_offset != 0) {
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len = header.backing_file_size;
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if (len > 1023) {
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len = 1023;
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}
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ret = bdrv_pread(bs->file, header.backing_file_offset,
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bs->backing_file, len);
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if (ret < 0) {
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goto fail;
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}
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bs->backing_file[len] = '\0';
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}
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if (qcow2_read_snapshots(bs) < 0) {
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ret = -EINVAL;
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goto fail;
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}
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#ifdef DEBUG_ALLOC
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qcow2_check_refcounts(bs);
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#endif
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return ret;
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fail:
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qcow2_free_snapshots(bs);
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qcow2_refcount_close(bs);
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qemu_free(s->l1_table);
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qemu_free(s->l2_cache);
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qemu_free(s->cluster_cache);
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qemu_free(s->cluster_data);
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return ret;
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}
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static int qcow2_set_key(BlockDriverState *bs, const char *key)
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{
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BDRVQcowState *s = bs->opaque;
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uint8_t keybuf[16];
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int len, i;
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memset(keybuf, 0, 16);
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len = strlen(key);
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if (len > 16)
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len = 16;
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/* XXX: we could compress the chars to 7 bits to increase
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entropy */
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for(i = 0;i < len;i++) {
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keybuf[i] = key[i];
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}
|
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s->crypt_method = s->crypt_method_header;
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|
|
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if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0)
|
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return -1;
|
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if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0)
|
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return -1;
|
|
#if 0
|
|
/* test */
|
|
{
|
|
uint8_t in[16];
|
|
uint8_t out[16];
|
|
uint8_t tmp[16];
|
|
for(i=0;i<16;i++)
|
|
in[i] = i;
|
|
AES_encrypt(in, tmp, &s->aes_encrypt_key);
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|
AES_decrypt(tmp, out, &s->aes_decrypt_key);
|
|
for(i = 0; i < 16; i++)
|
|
printf(" %02x", tmp[i]);
|
|
printf("\n");
|
|
for(i = 0; i < 16; i++)
|
|
printf(" %02x", out[i]);
|
|
printf("\n");
|
|
}
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static int qcow2_is_allocated(BlockDriverState *bs, int64_t sector_num,
|
|
int nb_sectors, int *pnum)
|
|
{
|
|
uint64_t cluster_offset;
|
|
int ret;
|
|
|
|
*pnum = nb_sectors;
|
|
/* FIXME We can get errors here, but the bdrv_is_allocated interface can't
|
|
* pass them on today */
|
|
ret = qcow2_get_cluster_offset(bs, sector_num << 9, pnum, &cluster_offset);
|
|
if (ret < 0) {
|
|
*pnum = 0;
|
|
}
|
|
|
|
return (cluster_offset != 0);
|
|
}
|
|
|
|
/* handle reading after the end of the backing file */
|
|
int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
|
|
int64_t sector_num, int nb_sectors)
|
|
{
|
|
int n1;
|
|
if ((sector_num + nb_sectors) <= bs->total_sectors)
|
|
return nb_sectors;
|
|
if (sector_num >= bs->total_sectors)
|
|
n1 = 0;
|
|
else
|
|
n1 = bs->total_sectors - sector_num;
|
|
|
|
qemu_iovec_memset(qiov, 0, 512 * (nb_sectors - n1));
|
|
|
|
return n1;
|
|
}
|
|
|
|
typedef struct QCowAIOCB {
|
|
BlockDriverAIOCB common;
|
|
int64_t sector_num;
|
|
QEMUIOVector *qiov;
|
|
int remaining_sectors;
|
|
int cur_nr_sectors; /* number of sectors in current iteration */
|
|
uint64_t bytes_done;
|
|
uint64_t cluster_offset;
|
|
uint8_t *cluster_data;
|
|
BlockDriverAIOCB *hd_aiocb;
|
|
QEMUIOVector hd_qiov;
|
|
QEMUBH *bh;
|
|
QCowL2Meta l2meta;
|
|
QLIST_ENTRY(QCowAIOCB) next_depend;
|
|
} QCowAIOCB;
|
|
|
|
static void qcow2_aio_cancel(BlockDriverAIOCB *blockacb)
|
|
{
|
|
QCowAIOCB *acb = container_of(blockacb, QCowAIOCB, common);
|
|
if (acb->hd_aiocb)
|
|
bdrv_aio_cancel(acb->hd_aiocb);
|
|
qemu_aio_release(acb);
|
|
}
|
|
|
|
static AIOPool qcow2_aio_pool = {
|
|
.aiocb_size = sizeof(QCowAIOCB),
|
|
.cancel = qcow2_aio_cancel,
|
|
};
|
|
|
|
static void qcow2_aio_read_cb(void *opaque, int ret);
|
|
static void qcow2_aio_read_bh(void *opaque)
|
|
{
|
|
QCowAIOCB *acb = opaque;
|
|
qemu_bh_delete(acb->bh);
|
|
acb->bh = NULL;
|
|
qcow2_aio_read_cb(opaque, 0);
|
|
}
|
|
|
|
static int qcow2_schedule_bh(QEMUBHFunc *cb, QCowAIOCB *acb)
|
|
{
|
|
if (acb->bh)
|
|
return -EIO;
|
|
|
|
acb->bh = qemu_bh_new(cb, acb);
|
|
if (!acb->bh)
|
|
return -EIO;
|
|
|
|
qemu_bh_schedule(acb->bh);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void qcow2_aio_read_cb(void *opaque, int ret)
|
|
{
|
|
QCowAIOCB *acb = opaque;
|
|
BlockDriverState *bs = acb->common.bs;
|
|
BDRVQcowState *s = bs->opaque;
|
|
int index_in_cluster, n1;
|
|
|
|
acb->hd_aiocb = NULL;
|
|
if (ret < 0)
|
|
goto done;
|
|
|
|
/* post process the read buffer */
|
|
if (!acb->cluster_offset) {
|
|
/* nothing to do */
|
|
} else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) {
|
|
/* nothing to do */
|
|
} else {
|
|
if (s->crypt_method) {
|
|
qcow2_encrypt_sectors(s, acb->sector_num, acb->cluster_data,
|
|
acb->cluster_data, acb->cur_nr_sectors, 0, &s->aes_decrypt_key);
|
|
qemu_iovec_reset(&acb->hd_qiov);
|
|
qemu_iovec_copy(&acb->hd_qiov, acb->qiov, acb->bytes_done,
|
|
acb->cur_nr_sectors * 512);
|
|
qemu_iovec_from_buffer(&acb->hd_qiov, acb->cluster_data,
|
|
512 * acb->cur_nr_sectors);
|
|
}
|
|
}
|
|
|
|
acb->remaining_sectors -= acb->cur_nr_sectors;
|
|
acb->sector_num += acb->cur_nr_sectors;
|
|
acb->bytes_done += acb->cur_nr_sectors * 512;
|
|
|
|
if (acb->remaining_sectors == 0) {
|
|
/* request completed */
|
|
ret = 0;
|
|
goto done;
|
|
}
|
|
|
|
/* prepare next AIO request */
|
|
acb->cur_nr_sectors = acb->remaining_sectors;
|
|
if (s->crypt_method) {
|
|
acb->cur_nr_sectors = MIN(acb->cur_nr_sectors,
|
|
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors);
|
|
}
|
|
|
|
ret = qcow2_get_cluster_offset(bs, acb->sector_num << 9,
|
|
&acb->cur_nr_sectors, &acb->cluster_offset);
|
|
if (ret < 0) {
|
|
goto done;
|
|
}
|
|
|
|
index_in_cluster = acb->sector_num & (s->cluster_sectors - 1);
|
|
|
|
qemu_iovec_reset(&acb->hd_qiov);
|
|
qemu_iovec_copy(&acb->hd_qiov, acb->qiov, acb->bytes_done,
|
|
acb->cur_nr_sectors * 512);
|
|
|
|
if (!acb->cluster_offset) {
|
|
|
|
if (bs->backing_hd) {
|
|
/* read from the base image */
|
|
n1 = qcow2_backing_read1(bs->backing_hd, &acb->hd_qiov,
|
|
acb->sector_num, acb->cur_nr_sectors);
|
|
if (n1 > 0) {
|
|
BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO);
|
|
acb->hd_aiocb = bdrv_aio_readv(bs->backing_hd, acb->sector_num,
|
|
&acb->hd_qiov, acb->cur_nr_sectors,
|
|
qcow2_aio_read_cb, acb);
|
|
if (acb->hd_aiocb == NULL)
|
|
goto done;
|
|
} else {
|
|
ret = qcow2_schedule_bh(qcow2_aio_read_bh, acb);
|
|
if (ret < 0)
|
|
goto done;
|
|
}
|
|
} else {
|
|
/* Note: in this case, no need to wait */
|
|
qemu_iovec_memset(&acb->hd_qiov, 0, 512 * acb->cur_nr_sectors);
|
|
ret = qcow2_schedule_bh(qcow2_aio_read_bh, acb);
|
|
if (ret < 0)
|
|
goto done;
|
|
}
|
|
} else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) {
|
|
/* add AIO support for compressed blocks ? */
|
|
if (qcow2_decompress_cluster(bs, acb->cluster_offset) < 0)
|
|
goto done;
|
|
|
|
qemu_iovec_from_buffer(&acb->hd_qiov,
|
|
s->cluster_cache + index_in_cluster * 512,
|
|
512 * acb->cur_nr_sectors);
|
|
|
|
ret = qcow2_schedule_bh(qcow2_aio_read_bh, acb);
|
|
if (ret < 0)
|
|
goto done;
|
|
} else {
|
|
if ((acb->cluster_offset & 511) != 0) {
|
|
ret = -EIO;
|
|
goto done;
|
|
}
|
|
|
|
if (s->crypt_method) {
|
|
/*
|
|
* For encrypted images, read everything into a temporary
|
|
* contiguous buffer on which the AES functions can work.
|
|
*/
|
|
if (!acb->cluster_data) {
|
|
acb->cluster_data =
|
|
qemu_mallocz(QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
|
|
}
|
|
|
|
assert(acb->cur_nr_sectors <=
|
|
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors);
|
|
qemu_iovec_reset(&acb->hd_qiov);
|
|
qemu_iovec_add(&acb->hd_qiov, acb->cluster_data,
|
|
512 * acb->cur_nr_sectors);
|
|
}
|
|
|
|
BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO);
|
|
acb->hd_aiocb = bdrv_aio_readv(bs->file,
|
|
(acb->cluster_offset >> 9) + index_in_cluster,
|
|
&acb->hd_qiov, acb->cur_nr_sectors,
|
|
qcow2_aio_read_cb, acb);
|
|
if (acb->hd_aiocb == NULL) {
|
|
ret = -EIO;
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
return;
|
|
done:
|
|
acb->common.cb(acb->common.opaque, ret);
|
|
qemu_iovec_destroy(&acb->hd_qiov);
|
|
qemu_aio_release(acb);
|
|
}
|
|
|
|
static QCowAIOCB *qcow2_aio_setup(BlockDriverState *bs, int64_t sector_num,
|
|
QEMUIOVector *qiov, int nb_sectors,
|
|
BlockDriverCompletionFunc *cb,
|
|
void *opaque, int is_write)
|
|
{
|
|
QCowAIOCB *acb;
|
|
|
|
acb = qemu_aio_get(&qcow2_aio_pool, bs, cb, opaque);
|
|
if (!acb)
|
|
return NULL;
|
|
acb->hd_aiocb = NULL;
|
|
acb->sector_num = sector_num;
|
|
acb->qiov = qiov;
|
|
|
|
qemu_iovec_init(&acb->hd_qiov, qiov->niov);
|
|
|
|
acb->bytes_done = 0;
|
|
acb->remaining_sectors = nb_sectors;
|
|
acb->cur_nr_sectors = 0;
|
|
acb->cluster_offset = 0;
|
|
acb->l2meta.nb_clusters = 0;
|
|
QLIST_INIT(&acb->l2meta.dependent_requests);
|
|
return acb;
|
|
}
|
|
|
|
static BlockDriverAIOCB *qcow2_aio_readv(BlockDriverState *bs,
|
|
int64_t sector_num,
|
|
QEMUIOVector *qiov, int nb_sectors,
|
|
BlockDriverCompletionFunc *cb,
|
|
void *opaque)
|
|
{
|
|
QCowAIOCB *acb;
|
|
|
|
acb = qcow2_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
|
|
if (!acb)
|
|
return NULL;
|
|
|
|
qcow2_aio_read_cb(acb, 0);
|
|
return &acb->common;
|
|
}
|
|
|
|
static void qcow2_aio_write_cb(void *opaque, int ret);
|
|
|
|
static void run_dependent_requests(QCowL2Meta *m)
|
|
{
|
|
QCowAIOCB *req;
|
|
QCowAIOCB *next;
|
|
|
|
/* Take the request off the list of running requests */
|
|
if (m->nb_clusters != 0) {
|
|
QLIST_REMOVE(m, next_in_flight);
|
|
}
|
|
|
|
/* Restart all dependent requests */
|
|
QLIST_FOREACH_SAFE(req, &m->dependent_requests, next_depend, next) {
|
|
qcow2_aio_write_cb(req, 0);
|
|
}
|
|
|
|
/* Empty the list for the next part of the request */
|
|
QLIST_INIT(&m->dependent_requests);
|
|
}
|
|
|
|
static void qcow2_aio_write_cb(void *opaque, int ret)
|
|
{
|
|
QCowAIOCB *acb = opaque;
|
|
BlockDriverState *bs = acb->common.bs;
|
|
BDRVQcowState *s = bs->opaque;
|
|
int index_in_cluster;
|
|
int n_end;
|
|
|
|
acb->hd_aiocb = NULL;
|
|
|
|
if (ret >= 0) {
|
|
ret = qcow2_alloc_cluster_link_l2(bs, &acb->l2meta);
|
|
}
|
|
|
|
run_dependent_requests(&acb->l2meta);
|
|
|
|
if (ret < 0)
|
|
goto done;
|
|
|
|
acb->remaining_sectors -= acb->cur_nr_sectors;
|
|
acb->sector_num += acb->cur_nr_sectors;
|
|
acb->bytes_done += acb->cur_nr_sectors * 512;
|
|
|
|
if (acb->remaining_sectors == 0) {
|
|
/* request completed */
|
|
ret = 0;
|
|
goto done;
|
|
}
|
|
|
|
index_in_cluster = acb->sector_num & (s->cluster_sectors - 1);
|
|
n_end = index_in_cluster + acb->remaining_sectors;
|
|
if (s->crypt_method &&
|
|
n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors)
|
|
n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors;
|
|
|
|
ret = qcow2_alloc_cluster_offset(bs, acb->sector_num << 9,
|
|
index_in_cluster, n_end, &acb->cur_nr_sectors, &acb->l2meta);
|
|
if (ret < 0) {
|
|
goto done;
|
|
}
|
|
|
|
acb->cluster_offset = acb->l2meta.cluster_offset;
|
|
|
|
/* Need to wait for another request? If so, we are done for now. */
|
|
if (acb->l2meta.nb_clusters == 0 && acb->l2meta.depends_on != NULL) {
|
|
QLIST_INSERT_HEAD(&acb->l2meta.depends_on->dependent_requests,
|
|
acb, next_depend);
|
|
return;
|
|
}
|
|
|
|
assert((acb->cluster_offset & 511) == 0);
|
|
|
|
qemu_iovec_reset(&acb->hd_qiov);
|
|
qemu_iovec_copy(&acb->hd_qiov, acb->qiov, acb->bytes_done,
|
|
acb->cur_nr_sectors * 512);
|
|
|
|
if (s->crypt_method) {
|
|
if (!acb->cluster_data) {
|
|
acb->cluster_data = qemu_mallocz(QCOW_MAX_CRYPT_CLUSTERS *
|
|
s->cluster_size);
|
|
}
|
|
|
|
assert(acb->hd_qiov.size <= QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
|
|
qemu_iovec_to_buffer(&acb->hd_qiov, acb->cluster_data);
|
|
|
|
qcow2_encrypt_sectors(s, acb->sector_num, acb->cluster_data,
|
|
acb->cluster_data, acb->cur_nr_sectors, 1, &s->aes_encrypt_key);
|
|
|
|
qemu_iovec_reset(&acb->hd_qiov);
|
|
qemu_iovec_add(&acb->hd_qiov, acb->cluster_data,
|
|
acb->cur_nr_sectors * 512);
|
|
}
|
|
|
|
BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
|
|
acb->hd_aiocb = bdrv_aio_writev(bs->file,
|
|
(acb->cluster_offset >> 9) + index_in_cluster,
|
|
&acb->hd_qiov, acb->cur_nr_sectors,
|
|
qcow2_aio_write_cb, acb);
|
|
if (acb->hd_aiocb == NULL) {
|
|
ret = -EIO;
|
|
goto fail;
|
|
}
|
|
|
|
return;
|
|
|
|
fail:
|
|
if (acb->l2meta.nb_clusters != 0) {
|
|
QLIST_REMOVE(&acb->l2meta, next_in_flight);
|
|
}
|
|
done:
|
|
acb->common.cb(acb->common.opaque, ret);
|
|
qemu_iovec_destroy(&acb->hd_qiov);
|
|
qemu_aio_release(acb);
|
|
}
|
|
|
|
static BlockDriverAIOCB *qcow2_aio_writev(BlockDriverState *bs,
|
|
int64_t sector_num,
|
|
QEMUIOVector *qiov, int nb_sectors,
|
|
BlockDriverCompletionFunc *cb,
|
|
void *opaque)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
QCowAIOCB *acb;
|
|
|
|
s->cluster_cache_offset = -1; /* disable compressed cache */
|
|
|
|
acb = qcow2_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
|
|
if (!acb)
|
|
return NULL;
|
|
|
|
qcow2_aio_write_cb(acb, 0);
|
|
return &acb->common;
|
|
}
|
|
|
|
static void qcow2_close(BlockDriverState *bs)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
qemu_free(s->l1_table);
|
|
qemu_free(s->l2_cache);
|
|
qemu_free(s->cluster_cache);
|
|
qemu_free(s->cluster_data);
|
|
qcow2_refcount_close(bs);
|
|
}
|
|
|
|
/*
|
|
* Updates the variable length parts of the qcow2 header, i.e. the backing file
|
|
* name and all extensions. qcow2 was not designed to allow such changes, so if
|
|
* we run out of space (we can only use the first cluster) this function may
|
|
* fail.
|
|
*
|
|
* Returns 0 on success, -errno in error cases.
|
|
*/
|
|
static int qcow2_update_ext_header(BlockDriverState *bs,
|
|
const char *backing_file, const char *backing_fmt)
|
|
{
|
|
size_t backing_file_len = 0;
|
|
size_t backing_fmt_len = 0;
|
|
BDRVQcowState *s = bs->opaque;
|
|
QCowExtension ext_backing_fmt = {0, 0};
|
|
int ret;
|
|
|
|
/* Backing file format doesn't make sense without a backing file */
|
|
if (backing_fmt && !backing_file) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Prepare the backing file format extension if needed */
|
|
if (backing_fmt) {
|
|
ext_backing_fmt.len = cpu_to_be32(strlen(backing_fmt));
|
|
ext_backing_fmt.magic = cpu_to_be32(QCOW2_EXT_MAGIC_BACKING_FORMAT);
|
|
backing_fmt_len = ((sizeof(ext_backing_fmt)
|
|
+ strlen(backing_fmt) + 7) & ~7);
|
|
}
|
|
|
|
/* Check if we can fit the new header into the first cluster */
|
|
if (backing_file) {
|
|
backing_file_len = strlen(backing_file);
|
|
}
|
|
|
|
size_t header_size = sizeof(QCowHeader) + backing_file_len
|
|
+ backing_fmt_len;
|
|
|
|
if (header_size > s->cluster_size) {
|
|
return -ENOSPC;
|
|
}
|
|
|
|
/* Rewrite backing file name and qcow2 extensions */
|
|
size_t ext_size = header_size - sizeof(QCowHeader);
|
|
uint8_t buf[ext_size];
|
|
size_t offset = 0;
|
|
size_t backing_file_offset = 0;
|
|
|
|
if (backing_file) {
|
|
if (backing_fmt) {
|
|
int padding = backing_fmt_len -
|
|
(sizeof(ext_backing_fmt) + strlen(backing_fmt));
|
|
|
|
memcpy(buf + offset, &ext_backing_fmt, sizeof(ext_backing_fmt));
|
|
offset += sizeof(ext_backing_fmt);
|
|
|
|
memcpy(buf + offset, backing_fmt, strlen(backing_fmt));
|
|
offset += strlen(backing_fmt);
|
|
|
|
memset(buf + offset, 0, padding);
|
|
offset += padding;
|
|
}
|
|
|
|
memcpy(buf + offset, backing_file, backing_file_len);
|
|
backing_file_offset = sizeof(QCowHeader) + offset;
|
|
}
|
|
|
|
ret = bdrv_pwrite_sync(bs->file, sizeof(QCowHeader), buf, ext_size);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
/* Update header fields */
|
|
uint64_t be_backing_file_offset = cpu_to_be64(backing_file_offset);
|
|
uint32_t be_backing_file_size = cpu_to_be32(backing_file_len);
|
|
|
|
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, backing_file_offset),
|
|
&be_backing_file_offset, sizeof(uint64_t));
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, backing_file_size),
|
|
&be_backing_file_size, sizeof(uint32_t));
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
ret = 0;
|
|
fail:
|
|
return ret;
|
|
}
|
|
|
|
static int qcow2_change_backing_file(BlockDriverState *bs,
|
|
const char *backing_file, const char *backing_fmt)
|
|
{
|
|
return qcow2_update_ext_header(bs, backing_file, backing_fmt);
|
|
}
|
|
|
|
static int preallocate(BlockDriverState *bs)
|
|
{
|
|
uint64_t nb_sectors;
|
|
uint64_t offset;
|
|
int num;
|
|
int ret;
|
|
QCowL2Meta meta;
|
|
|
|
nb_sectors = bdrv_getlength(bs) >> 9;
|
|
offset = 0;
|
|
QLIST_INIT(&meta.dependent_requests);
|
|
meta.cluster_offset = 0;
|
|
|
|
while (nb_sectors) {
|
|
num = MIN(nb_sectors, INT_MAX >> 9);
|
|
ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num, &meta);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
ret = qcow2_alloc_cluster_link_l2(bs, &meta);
|
|
if (ret < 0) {
|
|
qcow2_free_any_clusters(bs, meta.cluster_offset, meta.nb_clusters);
|
|
return ret;
|
|
}
|
|
|
|
/* There are no dependent requests, but we need to remove our request
|
|
* from the list of in-flight requests */
|
|
run_dependent_requests(&meta);
|
|
|
|
/* TODO Preallocate data if requested */
|
|
|
|
nb_sectors -= num;
|
|
offset += num << 9;
|
|
}
|
|
|
|
/*
|
|
* It is expected that the image file is large enough to actually contain
|
|
* all of the allocated clusters (otherwise we get failing reads after
|
|
* EOF). Extend the image to the last allocated sector.
|
|
*/
|
|
if (meta.cluster_offset != 0) {
|
|
uint8_t buf[512];
|
|
memset(buf, 0, 512);
|
|
ret = bdrv_write(bs->file, (meta.cluster_offset >> 9) + num - 1, buf, 1);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int qcow2_create2(const char *filename, int64_t total_size,
|
|
const char *backing_file, const char *backing_format,
|
|
int flags, size_t cluster_size, int prealloc,
|
|
QEMUOptionParameter *options)
|
|
{
|
|
/* Calulate cluster_bits */
|
|
int cluster_bits;
|
|
cluster_bits = ffs(cluster_size) - 1;
|
|
if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS ||
|
|
(1 << cluster_bits) != cluster_size)
|
|
{
|
|
error_report(
|
|
"Cluster size must be a power of two between %d and %dk\n",
|
|
1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10));
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Open the image file and write a minimal qcow2 header.
|
|
*
|
|
* We keep things simple and start with a zero-sized image. We also
|
|
* do without refcount blocks or a L1 table for now. We'll fix the
|
|
* inconsistency later.
|
|
*
|
|
* We do need a refcount table because growing the refcount table means
|
|
* allocating two new refcount blocks - the seconds of which would be at
|
|
* 2 GB for 64k clusters, and we don't want to have a 2 GB initial file
|
|
* size for any qcow2 image.
|
|
*/
|
|
BlockDriverState* bs;
|
|
QCowHeader header;
|
|
uint8_t* refcount_table;
|
|
int ret;
|
|
|
|
ret = bdrv_create_file(filename, options);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
ret = bdrv_file_open(&bs, filename, BDRV_O_RDWR);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
/* Write the header */
|
|
memset(&header, 0, sizeof(header));
|
|
header.magic = cpu_to_be32(QCOW_MAGIC);
|
|
header.version = cpu_to_be32(QCOW_VERSION);
|
|
header.cluster_bits = cpu_to_be32(cluster_bits);
|
|
header.size = cpu_to_be64(0);
|
|
header.l1_table_offset = cpu_to_be64(0);
|
|
header.l1_size = cpu_to_be32(0);
|
|
header.refcount_table_offset = cpu_to_be64(cluster_size);
|
|
header.refcount_table_clusters = cpu_to_be32(1);
|
|
|
|
if (flags & BLOCK_FLAG_ENCRYPT) {
|
|
header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
|
|
} else {
|
|
header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
|
|
}
|
|
|
|
ret = bdrv_pwrite(bs, 0, &header, sizeof(header));
|
|
if (ret < 0) {
|
|
goto out;
|
|
}
|
|
|
|
/* Write an empty refcount table */
|
|
refcount_table = qemu_mallocz(cluster_size);
|
|
ret = bdrv_pwrite(bs, cluster_size, refcount_table, cluster_size);
|
|
qemu_free(refcount_table);
|
|
|
|
if (ret < 0) {
|
|
goto out;
|
|
}
|
|
|
|
bdrv_close(bs);
|
|
|
|
/*
|
|
* And now open the image and make it consistent first (i.e. increase the
|
|
* refcount of the cluster that is occupied by the header and the refcount
|
|
* table)
|
|
*/
|
|
BlockDriver* drv = bdrv_find_format("qcow2");
|
|
assert(drv != NULL);
|
|
ret = bdrv_open(bs, filename, BDRV_O_RDWR | BDRV_O_NO_FLUSH, drv);
|
|
if (ret < 0) {
|
|
goto out;
|
|
}
|
|
|
|
ret = qcow2_alloc_clusters(bs, 2 * cluster_size);
|
|
if (ret < 0) {
|
|
goto out;
|
|
|
|
} else if (ret != 0) {
|
|
error_report("Huh, first cluster in empty image is already in use?");
|
|
abort();
|
|
}
|
|
|
|
/* Okay, now that we have a valid image, let's give it the right size */
|
|
ret = bdrv_truncate(bs, total_size * BDRV_SECTOR_SIZE);
|
|
if (ret < 0) {
|
|
goto out;
|
|
}
|
|
|
|
/* Want a backing file? There you go.*/
|
|
if (backing_file) {
|
|
ret = bdrv_change_backing_file(bs, backing_file, backing_format);
|
|
if (ret < 0) {
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* And if we're supposed to preallocate metadata, do that now */
|
|
if (prealloc) {
|
|
ret = preallocate(bs);
|
|
if (ret < 0) {
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
ret = 0;
|
|
out:
|
|
bdrv_delete(bs);
|
|
return ret;
|
|
}
|
|
|
|
static int qcow2_create(const char *filename, QEMUOptionParameter *options)
|
|
{
|
|
const char *backing_file = NULL;
|
|
const char *backing_fmt = NULL;
|
|
uint64_t sectors = 0;
|
|
int flags = 0;
|
|
size_t cluster_size = 65536;
|
|
int prealloc = 0;
|
|
|
|
/* Read out options */
|
|
while (options && options->name) {
|
|
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
|
|
sectors = options->value.n / 512;
|
|
} else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
|
|
backing_file = options->value.s;
|
|
} else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) {
|
|
backing_fmt = options->value.s;
|
|
} else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) {
|
|
flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0;
|
|
} else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) {
|
|
if (options->value.n) {
|
|
cluster_size = options->value.n;
|
|
}
|
|
} else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) {
|
|
if (!options->value.s || !strcmp(options->value.s, "off")) {
|
|
prealloc = 0;
|
|
} else if (!strcmp(options->value.s, "metadata")) {
|
|
prealloc = 1;
|
|
} else {
|
|
fprintf(stderr, "Invalid preallocation mode: '%s'\n",
|
|
options->value.s);
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
options++;
|
|
}
|
|
|
|
if (backing_file && prealloc) {
|
|
fprintf(stderr, "Backing file and preallocation cannot be used at "
|
|
"the same time\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return qcow2_create2(filename, sectors, backing_file, backing_fmt, flags,
|
|
cluster_size, prealloc, options);
|
|
}
|
|
|
|
static int qcow2_make_empty(BlockDriverState *bs)
|
|
{
|
|
#if 0
|
|
/* XXX: not correct */
|
|
BDRVQcowState *s = bs->opaque;
|
|
uint32_t l1_length = s->l1_size * sizeof(uint64_t);
|
|
int ret;
|
|
|
|
memset(s->l1_table, 0, l1_length);
|
|
if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0)
|
|
return -1;
|
|
ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
l2_cache_reset(bs);
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static int qcow2_truncate(BlockDriverState *bs, int64_t offset)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int ret, new_l1_size;
|
|
|
|
if (offset & 511) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* cannot proceed if image has snapshots */
|
|
if (s->nb_snapshots) {
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
/* shrinking is currently not supported */
|
|
if (offset < bs->total_sectors * 512) {
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
new_l1_size = size_to_l1(s, offset);
|
|
ret = qcow2_grow_l1_table(bs, new_l1_size, true);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
/* write updated header.size */
|
|
offset = cpu_to_be64(offset);
|
|
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size),
|
|
&offset, sizeof(uint64_t));
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
s->l1_vm_state_index = new_l1_size;
|
|
return 0;
|
|
}
|
|
|
|
/* XXX: put compressed sectors first, then all the cluster aligned
|
|
tables to avoid losing bytes in alignment */
|
|
static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num,
|
|
const uint8_t *buf, int nb_sectors)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
z_stream strm;
|
|
int ret, out_len;
|
|
uint8_t *out_buf;
|
|
uint64_t cluster_offset;
|
|
|
|
if (nb_sectors == 0) {
|
|
/* align end of file to a sector boundary to ease reading with
|
|
sector based I/Os */
|
|
cluster_offset = bdrv_getlength(bs->file);
|
|
cluster_offset = (cluster_offset + 511) & ~511;
|
|
bdrv_truncate(bs->file, cluster_offset);
|
|
return 0;
|
|
}
|
|
|
|
if (nb_sectors != s->cluster_sectors)
|
|
return -EINVAL;
|
|
|
|
out_buf = qemu_malloc(s->cluster_size + (s->cluster_size / 1000) + 128);
|
|
|
|
/* best compression, small window, no zlib header */
|
|
memset(&strm, 0, sizeof(strm));
|
|
ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION,
|
|
Z_DEFLATED, -12,
|
|
9, Z_DEFAULT_STRATEGY);
|
|
if (ret != 0) {
|
|
qemu_free(out_buf);
|
|
return -1;
|
|
}
|
|
|
|
strm.avail_in = s->cluster_size;
|
|
strm.next_in = (uint8_t *)buf;
|
|
strm.avail_out = s->cluster_size;
|
|
strm.next_out = out_buf;
|
|
|
|
ret = deflate(&strm, Z_FINISH);
|
|
if (ret != Z_STREAM_END && ret != Z_OK) {
|
|
qemu_free(out_buf);
|
|
deflateEnd(&strm);
|
|
return -1;
|
|
}
|
|
out_len = strm.next_out - out_buf;
|
|
|
|
deflateEnd(&strm);
|
|
|
|
if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
|
|
/* could not compress: write normal cluster */
|
|
bdrv_write(bs, sector_num, buf, s->cluster_sectors);
|
|
} else {
|
|
cluster_offset = qcow2_alloc_compressed_cluster_offset(bs,
|
|
sector_num << 9, out_len);
|
|
if (!cluster_offset)
|
|
return -1;
|
|
cluster_offset &= s->cluster_offset_mask;
|
|
BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED);
|
|
if (bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len) != out_len) {
|
|
qemu_free(out_buf);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
qemu_free(out_buf);
|
|
return 0;
|
|
}
|
|
|
|
static int qcow2_flush(BlockDriverState *bs)
|
|
{
|
|
return bdrv_flush(bs->file);
|
|
}
|
|
|
|
static BlockDriverAIOCB *qcow2_aio_flush(BlockDriverState *bs,
|
|
BlockDriverCompletionFunc *cb,
|
|
void *opaque)
|
|
{
|
|
return bdrv_aio_flush(bs->file, cb, opaque);
|
|
}
|
|
|
|
static int64_t qcow2_vm_state_offset(BDRVQcowState *s)
|
|
{
|
|
return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
|
|
}
|
|
|
|
static int qcow2_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
bdi->cluster_size = s->cluster_size;
|
|
bdi->vm_state_offset = qcow2_vm_state_offset(s);
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result)
|
|
{
|
|
return qcow2_check_refcounts(bs, result);
|
|
}
|
|
|
|
#if 0
|
|
static void dump_refcounts(BlockDriverState *bs)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int64_t nb_clusters, k, k1, size;
|
|
int refcount;
|
|
|
|
size = bdrv_getlength(bs->file);
|
|
nb_clusters = size_to_clusters(s, size);
|
|
for(k = 0; k < nb_clusters;) {
|
|
k1 = k;
|
|
refcount = get_refcount(bs, k);
|
|
k++;
|
|
while (k < nb_clusters && get_refcount(bs, k) == refcount)
|
|
k++;
|
|
printf("%" PRId64 ": refcount=%d nb=%" PRId64 "\n", k, refcount,
|
|
k - k1);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
static int qcow2_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
|
|
int64_t pos, int size)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int growable = bs->growable;
|
|
int ret;
|
|
|
|
BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE);
|
|
bs->growable = 1;
|
|
ret = bdrv_pwrite(bs, qcow2_vm_state_offset(s) + pos, buf, size);
|
|
bs->growable = growable;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int qcow2_load_vmstate(BlockDriverState *bs, uint8_t *buf,
|
|
int64_t pos, int size)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int growable = bs->growable;
|
|
int ret;
|
|
|
|
BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD);
|
|
bs->growable = 1;
|
|
ret = bdrv_pread(bs, qcow2_vm_state_offset(s) + pos, buf, size);
|
|
bs->growable = growable;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static QEMUOptionParameter qcow2_create_options[] = {
|
|
{
|
|
.name = BLOCK_OPT_SIZE,
|
|
.type = OPT_SIZE,
|
|
.help = "Virtual disk size"
|
|
},
|
|
{
|
|
.name = BLOCK_OPT_BACKING_FILE,
|
|
.type = OPT_STRING,
|
|
.help = "File name of a base image"
|
|
},
|
|
{
|
|
.name = BLOCK_OPT_BACKING_FMT,
|
|
.type = OPT_STRING,
|
|
.help = "Image format of the base image"
|
|
},
|
|
{
|
|
.name = BLOCK_OPT_ENCRYPT,
|
|
.type = OPT_FLAG,
|
|
.help = "Encrypt the image"
|
|
},
|
|
{
|
|
.name = BLOCK_OPT_CLUSTER_SIZE,
|
|
.type = OPT_SIZE,
|
|
.help = "qcow2 cluster size"
|
|
},
|
|
{
|
|
.name = BLOCK_OPT_PREALLOC,
|
|
.type = OPT_STRING,
|
|
.help = "Preallocation mode (allowed values: off, metadata)"
|
|
},
|
|
{ NULL }
|
|
};
|
|
|
|
static BlockDriver bdrv_qcow2 = {
|
|
.format_name = "qcow2",
|
|
.instance_size = sizeof(BDRVQcowState),
|
|
.bdrv_probe = qcow2_probe,
|
|
.bdrv_open = qcow2_open,
|
|
.bdrv_close = qcow2_close,
|
|
.bdrv_create = qcow2_create,
|
|
.bdrv_flush = qcow2_flush,
|
|
.bdrv_is_allocated = qcow2_is_allocated,
|
|
.bdrv_set_key = qcow2_set_key,
|
|
.bdrv_make_empty = qcow2_make_empty,
|
|
|
|
.bdrv_aio_readv = qcow2_aio_readv,
|
|
.bdrv_aio_writev = qcow2_aio_writev,
|
|
.bdrv_aio_flush = qcow2_aio_flush,
|
|
|
|
.bdrv_truncate = qcow2_truncate,
|
|
.bdrv_write_compressed = qcow2_write_compressed,
|
|
|
|
.bdrv_snapshot_create = qcow2_snapshot_create,
|
|
.bdrv_snapshot_goto = qcow2_snapshot_goto,
|
|
.bdrv_snapshot_delete = qcow2_snapshot_delete,
|
|
.bdrv_snapshot_list = qcow2_snapshot_list,
|
|
.bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp,
|
|
.bdrv_get_info = qcow2_get_info,
|
|
|
|
.bdrv_save_vmstate = qcow2_save_vmstate,
|
|
.bdrv_load_vmstate = qcow2_load_vmstate,
|
|
|
|
.bdrv_change_backing_file = qcow2_change_backing_file,
|
|
|
|
.create_options = qcow2_create_options,
|
|
.bdrv_check = qcow2_check,
|
|
};
|
|
|
|
static void bdrv_qcow2_init(void)
|
|
{
|
|
bdrv_register(&bdrv_qcow2);
|
|
}
|
|
|
|
block_init(bdrv_qcow2_init);
|