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Diffstat (limited to 'block/qcow2.h')
| -rw-r--r-- | block/qcow2.h | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/block/qcow2.h b/block/qcow2.h new file mode 100644 index 0000000..3a34212 --- /dev/null +++ b/block/qcow2.h @@ -0,0 +1,154 @@ +/* + * Block driver for the QCOW version 2 format + * + * Copyright (c) 2004-2006 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#ifndef BLOCK_QCOW2_H +#define BLOCK_QCOW2_H + +#include "aes.h" + +#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb) +#define QCOW_VERSION 2 + +#define QCOW_CRYPT_NONE 0 +#define QCOW_CRYPT_AES 1 + +#define QCOW_MAX_CRYPT_CLUSTERS 32 + +/* indicate that the refcount of the referenced cluster is exactly one. */ +#define QCOW_OFLAG_COPIED (1LL << 63) +/* indicate that the cluster is compressed (they never have the copied flag) */ +#define QCOW_OFLAG_COMPRESSED (1LL << 62) + +#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */ + +#define MIN_CLUSTER_BITS 9 +#define MAX_CLUSTER_BITS 16 + +#define L2_CACHE_SIZE 16 + +typedef struct QCowHeader { + uint32_t magic; + uint32_t version; + uint64_t backing_file_offset; + uint32_t backing_file_size; + uint32_t cluster_bits; + uint64_t size; /* in bytes */ + uint32_t crypt_method; + uint32_t l1_size; /* XXX: save number of clusters instead ? */ + uint64_t l1_table_offset; + uint64_t refcount_table_offset; + uint32_t refcount_table_clusters; + uint32_t nb_snapshots; + uint64_t snapshots_offset; +} QCowHeader; + +typedef struct QCowSnapshot { + uint64_t l1_table_offset; + uint32_t l1_size; + char *id_str; + char *name; + uint32_t vm_state_size; + uint32_t date_sec; + uint32_t date_nsec; + uint64_t vm_clock_nsec; +} QCowSnapshot; + +typedef struct BDRVQcowState { + BlockDriverState *hd; + int cluster_bits; + int cluster_size; + int cluster_sectors; + int l2_bits; + int l2_size; + int l1_size; + int l1_vm_state_index; + int csize_shift; + int csize_mask; + uint64_t cluster_offset_mask; + uint64_t l1_table_offset; + uint64_t *l1_table; + uint64_t *l2_cache; + uint64_t l2_cache_offsets[L2_CACHE_SIZE]; + uint32_t l2_cache_counts[L2_CACHE_SIZE]; + uint8_t *cluster_cache; + uint8_t *cluster_data; + uint64_t cluster_cache_offset; + + uint64_t *refcount_table; + uint64_t refcount_table_offset; + uint32_t refcount_table_size; + uint64_t refcount_block_cache_offset; + uint16_t *refcount_block_cache; + int64_t free_cluster_index; + int64_t free_byte_offset; + + uint32_t crypt_method; /* current crypt method, 0 if no key yet */ + uint32_t crypt_method_header; + AES_KEY aes_encrypt_key; + AES_KEY aes_decrypt_key; + uint64_t snapshots_offset; + int snapshots_size; + int nb_snapshots; + QCowSnapshot *snapshots; +} BDRVQcowState; + +/* XXX: use std qcow open function ? */ +typedef struct QCowCreateState { + int cluster_size; + int cluster_bits; + uint16_t *refcount_block; + uint64_t *refcount_table; + int64_t l1_table_offset; + int64_t refcount_table_offset; + int64_t refcount_block_offset; +} QCowCreateState; + +static int size_to_clusters(BDRVQcowState *s, int64_t size) +{ + return (size + (s->cluster_size - 1)) >> s->cluster_bits; +} + +// FIXME Need qcow2_ prefix to global functions + +/* qcow2.c functions */ +void l2_cache_reset(BlockDriverState *bs); + +/* qcow2-refcount.c functions */ +int refcount_init(BlockDriverState *bs); +void refcount_close(BlockDriverState *bs); + +int64_t alloc_clusters(BlockDriverState *bs, int64_t size); +int64_t alloc_bytes(BlockDriverState *bs, int size); +void free_clusters(BlockDriverState *bs, + int64_t offset, int64_t size); + +void create_refcount_update(QCowCreateState *s, int64_t offset, int64_t size); +int update_snapshot_refcount(BlockDriverState *bs, + int64_t l1_table_offset, + int l1_size, + int addend); + +int check_refcounts(BlockDriverState *bs); + +#endif |
