[mirror_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 "qemu/aes.h"
#include "block/coroutine.h"

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

#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)

#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)
/* The cluster reads as all zeros */
#define QCOW_OFLAG_ZERO (1LL << 0)

#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */

#define MIN_CLUSTER_BITS 9
#define MAX_CLUSTER_BITS 21

#define L2_CACHE_SIZE 16

/* Must be at least 4 to cover all cases of refcount table growth */
#define REFCOUNT_CACHE_SIZE 4

#define DEFAULT_CLUSTER_SIZE 65536


#define QCOW2_OPT_LAZY_REFCOUNTS "lazy_refcounts"

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;

    /* The following fields are only valid for version >= 3 */
    uint64_t incompatible_features;
    uint64_t compatible_features;
    uint64_t autoclear_features;

    uint32_t refcount_order;
    uint32_t header_length;
} QCowHeader;

typedef struct QCowSnapshot {
    uint64_t l1_table_offset;
    uint32_t l1_size;
    char *id_str;
    char *name;
    uint64_t disk_size;
    uint64_t vm_state_size;
    uint32_t date_sec;
    uint32_t date_nsec;
    uint64_t vm_clock_nsec;
} QCowSnapshot;

struct Qcow2Cache;
typedef struct Qcow2Cache Qcow2Cache;

typedef struct Qcow2UnknownHeaderExtension {
    uint32_t magic;
    uint32_t len;
    QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
    uint8_t data[];
} Qcow2UnknownHeaderExtension;

enum {
    QCOW2_FEAT_TYPE_INCOMPATIBLE    = 0,
    QCOW2_FEAT_TYPE_COMPATIBLE      = 1,
    QCOW2_FEAT_TYPE_AUTOCLEAR       = 2,
};

/* Incompatible feature bits */
enum {
    QCOW2_INCOMPAT_DIRTY_BITNR   = 0,
    QCOW2_INCOMPAT_DIRTY         = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,

    QCOW2_INCOMPAT_MASK          = QCOW2_INCOMPAT_DIRTY,
};

/* Compatible feature bits */
enum {
    QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
    QCOW2_COMPAT_LAZY_REFCOUNTS       = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,

    QCOW2_COMPAT_FEAT_MASK            = QCOW2_COMPAT_LAZY_REFCOUNTS,
};

enum qcow2_discard_type {
    QCOW2_DISCARD_NEVER = 0,
    QCOW2_DISCARD_ALWAYS,
    QCOW2_DISCARD_REQUEST,
    QCOW2_DISCARD_SNAPSHOT,
    QCOW2_DISCARD_OTHER,
    QCOW2_DISCARD_MAX
};

typedef struct Qcow2Feature {
    uint8_t type;
    uint8_t bit;
    char    name[46];
} QEMU_PACKED Qcow2Feature;

typedef struct BDRVQcowState {
    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;

    Qcow2Cache* l2_table_cache;
    Qcow2Cache* refcount_block_cache;

    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;
    int64_t free_cluster_index;
    int64_t free_byte_offset;

    CoMutex lock;

    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;

    int flags;
    int qcow_version;
    bool use_lazy_refcounts;

    uint64_t incompatible_features;
    uint64_t compatible_features;
    uint64_t autoclear_features;

    size_t unknown_header_fields_size;
    void* unknown_header_fields;
    QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
} 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;

typedef struct Qcow2COWRegion {
    /**
     * Offset of the COW region in bytes from the start of the first cluster
     * touched by the request.
     */
    uint64_t    offset;

    /** Number of sectors to copy */
    int         nb_sectors;
} Qcow2COWRegion;

/**
 * Describes an in-flight (part of a) write request that writes to clusters
 * that are not referenced in their L2 table yet.
 */
typedef struct QCowL2Meta
{
    /** Guest offset of the first newly allocated cluster */
    uint64_t offset;

    /** Host offset of the first newly allocated cluster */
    uint64_t alloc_offset;

    /**
     * Number of sectors from the start of the first allocated cluster to
     * the end of the (possibly shortened) request
     */
    int nb_available;

    /** Number of newly allocated clusters */
    int nb_clusters;

    /**
     * Requests that overlap with this allocation and wait to be restarted
     * when the allocating request has completed.
     */
    CoQueue dependent_requests;

    /**
     * The COW Region between the start of the first allocated cluster and the
     * area the guest actually writes to.
     */
    Qcow2COWRegion cow_start;

    /**
     * The COW Region between the area the guest actually writes to and the
     * end of the last allocated cluster.
     */
    Qcow2COWRegion cow_end;

    /** Pointer to next L2Meta of the same write request */
    struct QCowL2Meta *next;

    QLIST_ENTRY(QCowL2Meta) next_in_flight;
} QCowL2Meta;

enum {
    QCOW2_CLUSTER_UNALLOCATED,
    QCOW2_CLUSTER_NORMAL,
    QCOW2_CLUSTER_COMPRESSED,
    QCOW2_CLUSTER_ZERO
};

#define L1E_OFFSET_MASK 0x00ffffffffffff00ULL
#define L2E_OFFSET_MASK 0x00ffffffffffff00ULL
#define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL

#define REFT_OFFSET_MASK 0xffffffffffffff00ULL

static inline int64_t start_of_cluster(BDRVQcowState *s, int64_t offset)
{
    return offset & ~(s->cluster_size - 1);
}

static inline int64_t offset_into_cluster(BDRVQcowState *s, int64_t offset)
{
    return offset & (s->cluster_size - 1);
}

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

static inline int64_t size_to_l1(BDRVQcowState *s, int64_t size)
{
    int shift = s->cluster_bits + s->l2_bits;
    return (size + (1ULL << shift) - 1) >> shift;
}

static inline int offset_to_l2_index(BDRVQcowState *s, int64_t offset)
{
    return (offset >> s->cluster_bits) & (s->l2_size - 1);
}

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

static inline int qcow2_get_cluster_type(uint64_t l2_entry)
{
    if (l2_entry & QCOW_OFLAG_COMPRESSED) {
        return QCOW2_CLUSTER_COMPRESSED;
    } else if (l2_entry & QCOW_OFLAG_ZERO) {
        return QCOW2_CLUSTER_ZERO;
    } else if (!(l2_entry & L2E_OFFSET_MASK)) {
        return QCOW2_CLUSTER_UNALLOCATED;
    } else {
        return QCOW2_CLUSTER_NORMAL;
    }
}

/* Check whether refcounts are eager or lazy */
static inline bool qcow2_need_accurate_refcounts(BDRVQcowState *s)
{
    return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
}

static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
{
    return m->offset + m->cow_start.offset;
}

static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
{
    return m->offset + m->cow_end.offset
        + (m->cow_end.nb_sectors << BDRV_SECTOR_BITS);
}

// FIXME Need qcow2_ prefix to global functions

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

int qcow2_mark_dirty(BlockDriverState *bs);
int qcow2_update_header(BlockDriverState *bs);

/* 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);
int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
    int nb_clusters);
int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
void qcow2_free_clusters(BlockDriverState *bs,
                          int64_t offset, int64_t size,
                          enum qcow2_discard_type type);
void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
                             int nb_clusters, enum qcow2_discard_type type);

int qcow2_update_snapshot_refcount(BlockDriverState *bs,
    int64_t l1_table_offset, int l1_size, int addend);

int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
                          BdrvCheckMode fix);

/* qcow2-cluster.c functions */
int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
                        bool exact_size);
void qcow2_l2_cache_reset(BlockDriverState *bs);
int qcow2_decompress_cluster(BlockDriverState *bs, 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);

int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
    int *num, uint64_t *cluster_offset);
int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
    int n_start, int n_end, int *num, uint64_t *host_offset, 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, QCowL2Meta *m);
int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
    int nb_sectors);
int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors);

/* 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);
int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name);

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

/* qcow2-cache.c functions */
Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables);
int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);

void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
    Qcow2Cache *dependency);
void qcow2_cache_depends_on_flush(Qcow2Cache *c);

int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
    void **table);
int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
    void **table);
int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);

#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
753d9b82	28	#include "qemu/aes.h"
737e150e	29	#include "block/coroutine.h"
f7d0fe02	30
14899cdf FN	31	//#define DEBUG_ALLOC
	32	//#define DEBUG_ALLOC2
	33	//#define DEBUG_EXT
	34
f7d0fe02	35	#define QCOW_MAGIC (('Q' << 24) \| ('F' << 16) \| ('I' << 8) \| 0xfb)
f7d0fe02 KW	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)
6377af48 KW	46	/* The cluster reads as all zeros */
6377af48 KW	47	#define QCOW_OFLAG_ZERO (1LL << 0)
f7d0fe02 KW	48
	49	#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */
	50
	51	#define MIN_CLUSTER_BITS 9
80ee15a6	52	#define MAX_CLUSTER_BITS 21
f7d0fe02 KW	53
	54	#define L2_CACHE_SIZE 16
	55
29c1a730 KW	56	/* Must be at least 4 to cover all cases of refcount table growth */
	57	#define REFCOUNT_CACHE_SIZE 4
	58
99cce9fa KW	59	#define DEFAULT_CLUSTER_SIZE 65536
99cce9fa KW	60
acdfb480 KW	61
	62	#define QCOW2_OPT_LAZY_REFCOUNTS "lazy_refcounts"
	63
f7d0fe02 KW	64	typedef struct QCowHeader {
	65	uint32_t magic;
	66	uint32_t version;
	67	uint64_t backing_file_offset;
	68	uint32_t backing_file_size;
	69	uint32_t cluster_bits;
	70	uint64_t size; /* in bytes */
	71	uint32_t crypt_method;
	72	uint32_t l1_size; /* XXX: save number of clusters instead ? */
	73	uint64_t l1_table_offset;
	74	uint64_t refcount_table_offset;
	75	uint32_t refcount_table_clusters;
	76	uint32_t nb_snapshots;
	77	uint64_t snapshots_offset;
6744cbab KW	78
	79	/* The following fields are only valid for version >= 3 */
	80	uint64_t incompatible_features;
	81	uint64_t compatible_features;
	82	uint64_t autoclear_features;
	83
	84	uint32_t refcount_order;
	85	uint32_t header_length;
f7d0fe02 KW	86	} QCowHeader;
	87
	88	typedef struct QCowSnapshot {
	89	uint64_t l1_table_offset;
	90	uint32_t l1_size;
	91	char *id_str;
	92	char *name;
90b27759	93	uint64_t disk_size;
c2c9a466	94	uint64_t vm_state_size;
f7d0fe02 KW	95	uint32_t date_sec;
	96	uint32_t date_nsec;
	97	uint64_t vm_clock_nsec;
	98	} QCowSnapshot;
	99
49381094 KW	100	struct Qcow2Cache;
	101	typedef struct Qcow2Cache Qcow2Cache;
	102
75bab85c KW	103	typedef struct Qcow2UnknownHeaderExtension {
	104	uint32_t magic;
	105	uint32_t len;
	106	QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
	107	uint8_t data[];
	108	} Qcow2UnknownHeaderExtension;
	109
cfcc4c62 KW	110	enum {
	111	QCOW2_FEAT_TYPE_INCOMPATIBLE = 0,
	112	QCOW2_FEAT_TYPE_COMPATIBLE = 1,
	113	QCOW2_FEAT_TYPE_AUTOCLEAR = 2,
	114	};
	115
c61d0004 SH	116	/* Incompatible feature bits */
	117	enum {
	118	QCOW2_INCOMPAT_DIRTY_BITNR = 0,
	119	QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
	120
	121	QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY,
	122	};
	123
bfe8043e SH	124	/* Compatible feature bits */
	125	enum {
	126	QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
	127	QCOW2_COMPAT_LAZY_REFCOUNTS = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
	128
	129	QCOW2_COMPAT_FEAT_MASK = QCOW2_COMPAT_LAZY_REFCOUNTS,
	130	};
	131
6cfcb9b8 KW	132	enum qcow2_discard_type {
	133	QCOW2_DISCARD_NEVER = 0,
	134	QCOW2_DISCARD_ALWAYS,
	135	QCOW2_DISCARD_REQUEST,
	136	QCOW2_DISCARD_SNAPSHOT,
	137	QCOW2_DISCARD_OTHER,
	138	QCOW2_DISCARD_MAX
	139	};
	140
cfcc4c62 KW	141	typedef struct Qcow2Feature {
	142	uint8_t type;
	143	uint8_t bit;
	144	char name[46];
	145	} QEMU_PACKED Qcow2Feature;
	146
f7d0fe02	147	typedef struct BDRVQcowState {
f7d0fe02 KW	148	int cluster_bits;
	149	int cluster_size;
	150	int cluster_sectors;
	151	int l2_bits;
	152	int l2_size;
	153	int l1_size;
	154	int l1_vm_state_index;
	155	int csize_shift;
	156	int csize_mask;
	157	uint64_t cluster_offset_mask;
	158	uint64_t l1_table_offset;
	159	uint64_t *l1_table;
29c1a730 KW	160
	161	Qcow2Cache* l2_table_cache;
	162	Qcow2Cache* refcount_block_cache;
	163
f7d0fe02 KW	164	uint8_t *cluster_cache;
	165	uint8_t *cluster_data;
	166	uint64_t cluster_cache_offset;
72cf2d4f	167	QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
f7d0fe02 KW	168
	169	uint64_t *refcount_table;
	170	uint64_t refcount_table_offset;
	171	uint32_t refcount_table_size;
f7d0fe02 KW	172	int64_t free_cluster_index;
	173	int64_t free_byte_offset;
	174
68d100e9 KW	175	CoMutex lock;
68d100e9 KW	176
f7d0fe02 KW	177	uint32_t crypt_method; /* current crypt method, 0 if no key yet */
	178	uint32_t crypt_method_header;
	179	AES_KEY aes_encrypt_key;
	180	AES_KEY aes_decrypt_key;
	181	uint64_t snapshots_offset;
	182	int snapshots_size;
	183	int nb_snapshots;
	184	QCowSnapshot *snapshots;
06d9260f AL	185
06d9260f AL	186	int flags;
6744cbab	187	int qcow_version;
74c4510a	188	bool use_lazy_refcounts;
6744cbab KW	189
	190	uint64_t incompatible_features;
	191	uint64_t compatible_features;
	192	uint64_t autoclear_features;
	193
	194	size_t unknown_header_fields_size;
	195	void* unknown_header_fields;
75bab85c	196	QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
f7d0fe02 KW	197	} BDRVQcowState;
	198
	199	/* XXX: use std qcow open function ? */
	200	typedef struct QCowCreateState {
	201	int cluster_size;
	202	int cluster_bits;
	203	uint16_t *refcount_block;
	204	uint64_t *refcount_table;
	205	int64_t l1_table_offset;
	206	int64_t refcount_table_offset;
	207	int64_t refcount_block_offset;
	208	} QCowCreateState;
	209
f214978a KW	210	struct QCowAIOCB;
f214978a KW	211
593fb83c KW	212	typedef struct Qcow2COWRegion {
	213	/**
	214	* Offset of the COW region in bytes from the start of the first cluster
	215	* touched by the request.
	216	*/
	217	uint64_t offset;
	218
	219	/** Number of sectors to copy */
	220	int nb_sectors;
	221	} Qcow2COWRegion;
	222
f50f88b9 KW	223	/**
	224	* Describes an in-flight (part of a) write request that writes to clusters
	225	* that are not referenced in their L2 table yet.
	226	*/
45aba42f KW	227	typedef struct QCowL2Meta
45aba42f KW	228	{
1d3afd64	229	/** Guest offset of the first newly allocated cluster */
45aba42f	230	uint64_t offset;
1d3afd64	231
1d3afd64	232	/** Host offset of the first newly allocated cluster */
250196f1	233	uint64_t alloc_offset;
1d3afd64	234
1d3afd64 KW	235	/**
	236	* Number of sectors from the start of the first allocated cluster to
	237	* the end of the (possibly shortened) request
	238	*/
45aba42f	239	int nb_available;
1d3afd64 KW	240
1d3afd64 KW	241	/** Number of newly allocated clusters */
45aba42f	242	int nb_clusters;
1d3afd64 KW	243
	244	/**
	245	* Requests that overlap with this allocation and wait to be restarted
	246	* when the allocating request has completed.
	247	*/
68d100e9	248	CoQueue dependent_requests;
f214978a	249
593fb83c KW	250	/**
	251	* The COW Region between the start of the first allocated cluster and the
	252	* area the guest actually writes to.
	253	*/
	254	Qcow2COWRegion cow_start;
	255
	256	/**
	257	* The COW Region between the area the guest actually writes to and the
	258	* end of the last allocated cluster.
	259	*/
	260	Qcow2COWRegion cow_end;
	261
88c6588c KW	262	/** Pointer to next L2Meta of the same write request */
	263	struct QCowL2Meta *next;
	264
72cf2d4f	265	QLIST_ENTRY(QCowL2Meta) next_in_flight;
45aba42f KW	266	} QCowL2Meta;
45aba42f KW	267
68d000a3 KW	268	enum {
	269	QCOW2_CLUSTER_UNALLOCATED,
	270	QCOW2_CLUSTER_NORMAL,
	271	QCOW2_CLUSTER_COMPRESSED,
6377af48	272	QCOW2_CLUSTER_ZERO
68d000a3 KW	273	};
	274
	275	#define L1E_OFFSET_MASK 0x00ffffffffffff00ULL
	276	#define L2E_OFFSET_MASK 0x00ffffffffffff00ULL
	277	#define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
	278
76dc9e0c KW	279	#define REFT_OFFSET_MASK 0xffffffffffffff00ULL
76dc9e0c KW	280
3b8e2e26 KW	281	static inline int64_t start_of_cluster(BDRVQcowState *s, int64_t offset)
	282	{
	283	return offset & ~(s->cluster_size - 1);
	284	}
	285
c37f4cd7 KW	286	static inline int64_t offset_into_cluster(BDRVQcowState *s, int64_t offset)
	287	{
	288	return offset & (s->cluster_size - 1);
	289	}
	290
45aba42f	291	static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
f7d0fe02 KW	292	{
	293	return (size + (s->cluster_size - 1)) >> s->cluster_bits;
	294	}
	295
2cf7cfa1	296	static inline int64_t size_to_l1(BDRVQcowState *s, int64_t size)
419b19d9 SH	297	{
	298	int shift = s->cluster_bits + s->l2_bits;
	299	return (size + (1ULL << shift) - 1) >> shift;
	300	}
	301
17a71e58 KW	302	static inline int offset_to_l2_index(BDRVQcowState *s, int64_t offset)
	303	{
	304	return (offset >> s->cluster_bits) & (s->l2_size - 1);
	305	}
	306
c142442b KW	307	static inline int64_t align_offset(int64_t offset, int n)
	308	{
	309	offset = (offset + n - 1) & ~(n - 1);
	310	return offset;
	311	}
	312
68d000a3 KW	313	static inline int qcow2_get_cluster_type(uint64_t l2_entry)
	314	{
	315	if (l2_entry & QCOW_OFLAG_COMPRESSED) {
	316	return QCOW2_CLUSTER_COMPRESSED;
6377af48 KW	317	} else if (l2_entry & QCOW_OFLAG_ZERO) {
6377af48 KW	318	return QCOW2_CLUSTER_ZERO;
68d000a3 KW	319	} else if (!(l2_entry & L2E_OFFSET_MASK)) {
	320	return QCOW2_CLUSTER_UNALLOCATED;
	321	} else {
	322	return QCOW2_CLUSTER_NORMAL;
	323	}
	324	}
	325
bfe8043e SH	326	/* Check whether refcounts are eager or lazy */
	327	static inline bool qcow2_need_accurate_refcounts(BDRVQcowState *s)
	328	{
	329	return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
	330	}
c142442b	331
65eb2e35 KW	332	static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
	333	{
	334	return m->offset + m->cow_start.offset;
	335	}
	336
	337	static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
	338	{
	339	return m->offset + m->cow_end.offset
	340	+ (m->cow_end.nb_sectors << BDRV_SECTOR_BITS);
	341	}
	342
f7d0fe02 KW	343	// FIXME Need qcow2_ prefix to global functions
	344
	345	/* qcow2.c functions */
bd28f835 KW	346	int qcow2_backing_read1(BlockDriverState bs, QEMUIOVector qiov,
bd28f835 KW	347	int64_t sector_num, int nb_sectors);
280d3735 KW	348
280d3735 KW	349	int qcow2_mark_dirty(BlockDriverState *bs);
e24e49e6	350	int qcow2_update_header(BlockDriverState *bs);
f7d0fe02 KW	351
f7d0fe02 KW	352	/* qcow2-refcount.c functions */
ed6ccf0f KW	353	int qcow2_refcount_init(BlockDriverState *bs);
ed6ccf0f KW	354	void qcow2_refcount_close(BlockDriverState *bs);
f7d0fe02	355
ed6ccf0f	356	int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size);
256900b1 KW	357	int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
256900b1 KW	358	int nb_clusters);
ed6ccf0f KW	359	int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
ed6ccf0f KW	360	void qcow2_free_clusters(BlockDriverState *bs,
6cfcb9b8 KW	361	int64_t offset, int64_t size,
	362	enum qcow2_discard_type type);
	363	void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
	364	int nb_clusters, enum qcow2_discard_type type);
f7d0fe02	365
ed6ccf0f KW	366	int qcow2_update_snapshot_refcount(BlockDriverState *bs,
ed6ccf0f KW	367	int64_t l1_table_offset, int l1_size, int addend);
f7d0fe02	368
166acf54 KW	369	int qcow2_check_refcounts(BlockDriverState bs, BdrvCheckResult res,
166acf54 KW	370	BdrvCheckMode fix);
f7d0fe02	371
45aba42f	372	/* qcow2-cluster.c functions */
2cf7cfa1 KW	373	int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
2cf7cfa1 KW	374	bool exact_size);
ed6ccf0f	375	void qcow2_l2_cache_reset(BlockDriverState *bs);
66f82cee	376	int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
ed6ccf0f	377	void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
45aba42f KW	378	uint8_t out_buf, const uint8_t in_buf,
	379	int nb_sectors, int enc,
	380	const AES_KEY *key);
	381
1c46efaa KW	382	int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
1c46efaa KW	383	int num, uint64_t cluster_offset);
f4f0d391	384	int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
f50f88b9	385	int n_start, int n_end, int num, uint64_t host_offset, QCowL2Meta **m);
ed6ccf0f	386	uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
45aba42f KW	387	uint64_t offset,
	388	int compressed_size);
	389
148da7ea	390	int qcow2_alloc_cluster_link_l2(BlockDriverState bs, QCowL2Meta m);
5ea929e3 KW	391	int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
5ea929e3 KW	392	int nb_sectors);
621f0589	393	int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors);
45aba42f	394
c142442b	395	/* qcow2-snapshot.c functions */
ed6ccf0f KW	396	int qcow2_snapshot_create(BlockDriverState bs, QEMUSnapshotInfo sn_info);
	397	int qcow2_snapshot_goto(BlockDriverState bs, const char snapshot_id);
	398	int qcow2_snapshot_delete(BlockDriverState bs, const char snapshot_id);
	399	int qcow2_snapshot_list(BlockDriverState bs, QEMUSnapshotInfo *psn_tab);
51ef6727	400	int qcow2_snapshot_load_tmp(BlockDriverState bs, const char snapshot_name);
c142442b	401
ed6ccf0f KW	402	void qcow2_free_snapshots(BlockDriverState *bs);
ed6ccf0f KW	403	int qcow2_read_snapshots(BlockDriverState *bs);
c142442b	404
49381094	405	/* qcow2-cache.c functions */
6af4e9ea	406	Qcow2Cache qcow2_cache_create(BlockDriverState bs, int num_tables);
49381094 KW	407	int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);
	408
	409	void qcow2_cache_entry_mark_dirty(Qcow2Cache c, void table);
	410	int qcow2_cache_flush(BlockDriverState bs, Qcow2Cache c);
	411	int qcow2_cache_set_dependency(BlockDriverState bs, Qcow2Cache c,
	412	Qcow2Cache *dependency);
3de0a294	413	void qcow2_cache_depends_on_flush(Qcow2Cache *c);
49381094 KW	414
	415	int qcow2_cache_get(BlockDriverState bs, Qcow2Cache c, uint64_t offset,
	416	void **table);
	417	int qcow2_cache_get_empty(BlockDriverState bs, Qcow2Cache c, uint64_t offset,
	418	void **table);
	419	int qcow2_cache_put(BlockDriverState bs, Qcow2Cache c, void **table);
	420
f7d0fe02	421	#endif