[qemu.git] / block / qcow2.h

/*
 * 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 DEBUG_ALLOC
//#define DEBUG_ALLOC2
//#define DEBUG_EXT

#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 21

#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;
    QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;

    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;

struct QCowAIOCB;

/* XXX This could be private for qcow2-cluster.c */
typedef struct QCowL2Meta
{
    uint64_t offset;
    int n_start;
    int nb_available;
    int nb_clusters;
    struct QCowL2Meta *depends_on;
    QLIST_HEAD(QCowAioDependencies, QCowAIOCB) dependent_requests;

    QLIST_ENTRY(QCowL2Meta) next_in_flight;
} QCowL2Meta;

static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
{
    return (size + (s->cluster_size - 1)) >> s->cluster_bits;
}

static inline int64_t align_offset(int64_t offset, int n)
{
    offset = (offset + n - 1) & ~(n - 1);
    return offset;
}


// FIXME Need qcow2_ prefix to global functions

/* qcow2.c functions */
int qcow2_backing_read1(BlockDriverState *bs,
                  int64_t sector_num, uint8_t *buf, int nb_sectors);

/* qcow2-refcount.c functions */
int qcow2_refcount_init(BlockDriverState *bs);
void qcow2_refcount_close(BlockDriverState *bs);

int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size);
int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
void qcow2_free_clusters(BlockDriverState *bs,
    int64_t offset, int64_t size);
void qcow2_free_any_clusters(BlockDriverState *bs,
    uint64_t cluster_offset, int nb_clusters);

void qcow2_create_refcount_update(QCowCreateState *s, int64_t offset,
    int64_t size);
int qcow2_update_snapshot_refcount(BlockDriverState *bs,
    int64_t l1_table_offset, int l1_size, int addend);

int qcow2_check_refcounts(BlockDriverState *bs);

/* qcow2-cluster.c functions */
int qcow2_grow_l1_table(BlockDriverState *bs, int min_size);
void qcow2_l2_cache_reset(BlockDriverState *bs);
int qcow2_decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
                     uint8_t *out_buf, const uint8_t *in_buf,
                     int nb_sectors, int enc,
                     const AES_KEY *key);

uint64_t qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
    int *num);
uint64_t qcow2_alloc_cluster_offset(BlockDriverState *bs,
                              uint64_t offset,
                              int n_start, int n_end,
                              int *num, QCowL2Meta *m);
uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
                                         uint64_t offset,
                                         int compressed_size);

int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
    QCowL2Meta *m);

/* qcow2-snapshot.c functions */
int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);

void qcow2_free_snapshots(BlockDriverState *bs);
int qcow2_read_snapshots(BlockDriverState *bs);

#endif
Commit	Line	Data
f7d0fe02 KW	1	/*
	2	* Block driver for the QCOW version 2 format
	3	*
	4	* Copyright (c) 2004-2006 Fabrice Bellard
	5	*
	6	* Permission is hereby granted, free of charge, to any person obtaining a copy
	7	* of this software and associated documentation files (the "Software"), to deal
	8	* in the Software without restriction, including without limitation the rights
	9	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	10	* copies of the Software, and to permit persons to whom the Software is
	11	* furnished to do so, subject to the following conditions:
	12	*
	13	* The above copyright notice and this permission notice shall be included in
	14	* all copies or substantial portions of the Software.
	15	*
	16	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	17	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	18	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	19	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	20	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	21	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	22	* THE SOFTWARE.
	23	*/
	24
	25	#ifndef BLOCK_QCOW2_H
	26	#define BLOCK_QCOW2_H
	27
	28	#include "aes.h"
	29
14899cdf FN	30	//#define DEBUG_ALLOC
	31	//#define DEBUG_ALLOC2
	32	//#define DEBUG_EXT
	33
f7d0fe02 KW	34	#define QCOW_MAGIC (('Q' << 24) \| ('F' << 16) \| ('I' << 8) \| 0xfb)
	35	#define QCOW_VERSION 2
	36
	37	#define QCOW_CRYPT_NONE 0
	38	#define QCOW_CRYPT_AES 1
	39
	40	#define QCOW_MAX_CRYPT_CLUSTERS 32
	41
	42	/* indicate that the refcount of the referenced cluster is exactly one. */
	43	#define QCOW_OFLAG_COPIED (1LL << 63)
	44	/* indicate that the cluster is compressed (they never have the copied flag) */
	45	#define QCOW_OFLAG_COMPRESSED (1LL << 62)
	46
	47	#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */
	48
	49	#define MIN_CLUSTER_BITS 9
80ee15a6	50	#define MAX_CLUSTER_BITS 21
f7d0fe02 KW	51
	52	#define L2_CACHE_SIZE 16
	53
	54	typedef struct QCowHeader {
	55	uint32_t magic;
	56	uint32_t version;
	57	uint64_t backing_file_offset;
	58	uint32_t backing_file_size;
	59	uint32_t cluster_bits;
	60	uint64_t size; /* in bytes */
	61	uint32_t crypt_method;
	62	uint32_t l1_size; /* XXX: save number of clusters instead ? */
	63	uint64_t l1_table_offset;
	64	uint64_t refcount_table_offset;
	65	uint32_t refcount_table_clusters;
	66	uint32_t nb_snapshots;
	67	uint64_t snapshots_offset;
	68	} QCowHeader;
	69
	70	typedef struct QCowSnapshot {
	71	uint64_t l1_table_offset;
	72	uint32_t l1_size;
	73	char *id_str;
	74	char *name;
	75	uint32_t vm_state_size;
	76	uint32_t date_sec;
	77	uint32_t date_nsec;
	78	uint64_t vm_clock_nsec;
	79	} QCowSnapshot;
	80
	81	typedef struct BDRVQcowState {
	82	BlockDriverState *hd;
	83	int cluster_bits;
	84	int cluster_size;
	85	int cluster_sectors;
	86	int l2_bits;
	87	int l2_size;
	88	int l1_size;
	89	int l1_vm_state_index;
	90	int csize_shift;
	91	int csize_mask;
	92	uint64_t cluster_offset_mask;
	93	uint64_t l1_table_offset;
	94	uint64_t *l1_table;
	95	uint64_t *l2_cache;
	96	uint64_t l2_cache_offsets[L2_CACHE_SIZE];
	97	uint32_t l2_cache_counts[L2_CACHE_SIZE];
	98	uint8_t *cluster_cache;
	99	uint8_t *cluster_data;
	100	uint64_t cluster_cache_offset;
72cf2d4f	101	QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
f7d0fe02 KW	102
	103	uint64_t *refcount_table;
	104	uint64_t refcount_table_offset;
	105	uint32_t refcount_table_size;
	106	uint64_t refcount_block_cache_offset;
	107	uint16_t *refcount_block_cache;
	108	int64_t free_cluster_index;
	109	int64_t free_byte_offset;
	110
	111	uint32_t crypt_method; /* current crypt method, 0 if no key yet */
	112	uint32_t crypt_method_header;
	113	AES_KEY aes_encrypt_key;
	114	AES_KEY aes_decrypt_key;
	115	uint64_t snapshots_offset;
	116	int snapshots_size;
	117	int nb_snapshots;
	118	QCowSnapshot *snapshots;
	119	} BDRVQcowState;
	120
	121	/* XXX: use std qcow open function ? */
	122	typedef struct QCowCreateState {
	123	int cluster_size;
	124	int cluster_bits;
	125	uint16_t *refcount_block;
	126	uint64_t *refcount_table;
	127	int64_t l1_table_offset;
	128	int64_t refcount_table_offset;
	129	int64_t refcount_block_offset;
	130	} QCowCreateState;
	131
f214978a KW	132	struct QCowAIOCB;
f214978a KW	133
45aba42f KW	134	/* XXX This could be private for qcow2-cluster.c */
	135	typedef struct QCowL2Meta
	136	{
	137	uint64_t offset;
	138	int n_start;
	139	int nb_available;
	140	int nb_clusters;
f214978a	141	struct QCowL2Meta *depends_on;
72cf2d4f	142	QLIST_HEAD(QCowAioDependencies, QCowAIOCB) dependent_requests;
f214978a	143
72cf2d4f	144	QLIST_ENTRY(QCowL2Meta) next_in_flight;
45aba42f KW	145	} QCowL2Meta;
	146
	147	static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
f7d0fe02 KW	148	{
	149	return (size + (s->cluster_size - 1)) >> s->cluster_bits;
	150	}
	151
c142442b KW	152	static inline int64_t align_offset(int64_t offset, int n)
	153	{
	154	offset = (offset + n - 1) & ~(n - 1);
	155	return offset;
	156	}
	157
	158
f7d0fe02 KW	159	// FIXME Need qcow2_ prefix to global functions
	160
	161	/* qcow2.c functions */
ed6ccf0f	162	int qcow2_backing_read1(BlockDriverState *bs,
45aba42f	163	int64_t sector_num, uint8_t *buf, int nb_sectors);
f7d0fe02 KW	164
f7d0fe02 KW	165	/* qcow2-refcount.c functions */
ed6ccf0f KW	166	int qcow2_refcount_init(BlockDriverState *bs);
ed6ccf0f KW	167	void qcow2_refcount_close(BlockDriverState *bs);
f7d0fe02	168
ed6ccf0f KW	169	int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size);
	170	int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
	171	void qcow2_free_clusters(BlockDriverState *bs,
45aba42f	172	int64_t offset, int64_t size);
ed6ccf0f	173	void qcow2_free_any_clusters(BlockDriverState *bs,
45aba42f	174	uint64_t cluster_offset, int nb_clusters);
f7d0fe02	175
ed6ccf0f KW	176	void qcow2_create_refcount_update(QCowCreateState *s, int64_t offset,
	177	int64_t size);
	178	int qcow2_update_snapshot_refcount(BlockDriverState *bs,
	179	int64_t l1_table_offset, int l1_size, int addend);
f7d0fe02	180
ed6ccf0f	181	int qcow2_check_refcounts(BlockDriverState *bs);
f7d0fe02	182
45aba42f	183	/* qcow2-cluster.c functions */
ed6ccf0f KW	184	int qcow2_grow_l1_table(BlockDriverState *bs, int min_size);
	185	void qcow2_l2_cache_reset(BlockDriverState *bs);
	186	int qcow2_decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
	187	void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
45aba42f KW	188	uint8_t out_buf, const uint8_t in_buf,
	189	int nb_sectors, int enc,
	190	const AES_KEY *key);
	191
ed6ccf0f KW	192	uint64_t qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
	193	int *num);
	194	uint64_t qcow2_alloc_cluster_offset(BlockDriverState *bs,
45aba42f KW	195	uint64_t offset,
	196	int n_start, int n_end,
	197	int num, QCowL2Meta m);
ed6ccf0f	198	uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
45aba42f KW	199	uint64_t offset,
	200	int compressed_size);
	201
ed6ccf0f	202	int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
45aba42f KW	203	QCowL2Meta *m);
45aba42f KW	204
c142442b	205	/* qcow2-snapshot.c functions */
ed6ccf0f KW	206	int qcow2_snapshot_create(BlockDriverState bs, QEMUSnapshotInfo sn_info);
	207	int qcow2_snapshot_goto(BlockDriverState bs, const char snapshot_id);
	208	int qcow2_snapshot_delete(BlockDriverState bs, const char snapshot_id);
	209	int qcow2_snapshot_list(BlockDriverState bs, QEMUSnapshotInfo *psn_tab);
c142442b	210
ed6ccf0f KW	211	void qcow2_free_snapshots(BlockDriverState *bs);
ed6ccf0f KW	212	int qcow2_read_snapshots(BlockDriverState *bs);
c142442b	213
f7d0fe02	214	#endif