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diff --git a/qemu/block/qcow2.h b/qemu/block/qcow2.h
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+++ b/qemu/block/qcow2.h
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+/*
+ * 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 "crypto/cipher.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
+#define QCOW_MAX_SNAPSHOTS 65536
+
+/* 8 MB refcount table is enough for 2 PB images at 64k cluster size
+ * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */
+#define QCOW_MAX_REFTABLE_SIZE 0x800000
+
+/* 32 MB L1 table is enough for 2 PB images at 64k cluster size
+ * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */
+#define QCOW_MAX_L1_SIZE 0x2000000
+
+/* Allow for an average of 1k per snapshot table entry, should be plenty of
+ * space for snapshot names and IDs */
+#define QCOW_MAX_SNAPSHOTS_SIZE (1024 * QCOW_MAX_SNAPSHOTS)
+
+/* indicate that the refcount of the referenced cluster is exactly one. */
+#define QCOW_OFLAG_COPIED (1ULL << 63)
+/* indicate that the cluster is compressed (they never have the copied flag) */
+#define QCOW_OFLAG_COMPRESSED (1ULL << 62)
+/* The cluster reads as all zeros */
+#define QCOW_OFLAG_ZERO (1ULL << 0)
+
+#define MIN_CLUSTER_BITS 9
+#define MAX_CLUSTER_BITS 21
+
+/* Must be at least 2 to cover COW */
+#define MIN_L2_CACHE_SIZE 2 /* clusters */
+
+/* Must be at least 4 to cover all cases of refcount table growth */
+#define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */
+
+/* Whichever is more */
+#define DEFAULT_L2_CACHE_CLUSTERS 8 /* clusters */
+#define DEFAULT_L2_CACHE_BYTE_SIZE 1048576 /* bytes */
+
+/* The refblock cache needs only a fourth of the L2 cache size to cover as many
+ * clusters */
+#define DEFAULT_L2_REFCOUNT_SIZE_RATIO 4
+
+#define DEFAULT_CLUSTER_SIZE 65536
+
+
+#define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts"
+#define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request"
+#define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot"
+#define QCOW2_OPT_DISCARD_OTHER "pass-discard-other"
+#define QCOW2_OPT_OVERLAP "overlap-check"
+#define QCOW2_OPT_OVERLAP_TEMPLATE "overlap-check.template"
+#define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header"
+#define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1"
+#define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2"
+#define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table"
+#define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block"
+#define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table"
+#define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1"
+#define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2"
+#define QCOW2_OPT_CACHE_SIZE "cache-size"
+#define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size"
+#define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size"
+
+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;
+} QEMU_PACKED QCowHeader;
+
+typedef struct QEMU_PACKED QCowSnapshotHeader {
+ /* header is 8 byte aligned */
+ uint64_t l1_table_offset;
+
+ uint32_t l1_size;
+ uint16_t id_str_size;
+ uint16_t name_size;
+
+ uint32_t date_sec;
+ uint32_t date_nsec;
+
+ uint64_t vm_clock_nsec;
+
+ uint32_t vm_state_size;
+ uint32_t extra_data_size; /* for extension */
+ /* extra data follows */
+ /* id_str follows */
+ /* name follows */
+} QCowSnapshotHeader;
+
+typedef struct QEMU_PACKED QCowSnapshotExtraData {
+ uint64_t vm_state_size_large;
+ uint64_t disk_size;
+} QCowSnapshotExtraData;
+
+
+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_CORRUPT_BITNR = 1,
+ QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
+ QCOW2_INCOMPAT_CORRUPT = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
+
+ QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY
+ | QCOW2_INCOMPAT_CORRUPT,
+};
+
+/* 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 Qcow2DiscardRegion {
+ BlockDriverState *bs;
+ uint64_t offset;
+ uint64_t bytes;
+ QTAILQ_ENTRY(Qcow2DiscardRegion) next;
+} Qcow2DiscardRegion;
+
+typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array,
+ uint64_t index);
+typedef void Qcow2SetRefcountFunc(void *refcount_array,
+ uint64_t index, uint64_t value);
+
+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 refcount_block_bits;
+ int refcount_block_size;
+ 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;
+ uint64_t free_cluster_index;
+ uint64_t free_byte_offset;
+
+ CoMutex lock;
+
+ QCryptoCipher *cipher; /* current cipher, NULL if no key yet */
+ uint32_t crypt_method_header;
+ uint64_t snapshots_offset;
+ int snapshots_size;
+ unsigned int nb_snapshots;
+ QCowSnapshot *snapshots;
+
+ int flags;
+ int qcow_version;
+ bool use_lazy_refcounts;
+ int refcount_order;
+ int refcount_bits;
+ uint64_t refcount_max;
+
+ Qcow2GetRefcountFunc *get_refcount;
+ Qcow2SetRefcountFunc *set_refcount;
+
+ bool discard_passthrough[QCOW2_DISCARD_MAX];
+
+ int overlap_check; /* bitmask of Qcow2MetadataOverlap values */
+ bool signaled_corruption;
+
+ 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;
+ QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
+ bool cache_discards;
+
+ /* Backing file path and format as stored in the image (this is not the
+ * effective path/format, which may be the result of a runtime option
+ * override) */
+ char *image_backing_file;
+ char *image_backing_format;
+} BDRVQcowState;
+
+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
+};
+
+typedef enum QCow2MetadataOverlap {
+ QCOW2_OL_MAIN_HEADER_BITNR = 0,
+ QCOW2_OL_ACTIVE_L1_BITNR = 1,
+ QCOW2_OL_ACTIVE_L2_BITNR = 2,
+ QCOW2_OL_REFCOUNT_TABLE_BITNR = 3,
+ QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4,
+ QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5,
+ QCOW2_OL_INACTIVE_L1_BITNR = 6,
+ QCOW2_OL_INACTIVE_L2_BITNR = 7,
+
+ QCOW2_OL_MAX_BITNR = 8,
+
+ QCOW2_OL_NONE = 0,
+ QCOW2_OL_MAIN_HEADER = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
+ QCOW2_OL_ACTIVE_L1 = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
+ QCOW2_OL_ACTIVE_L2 = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
+ QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
+ QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
+ QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
+ QCOW2_OL_INACTIVE_L1 = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
+ /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv
+ * reads. */
+ QCOW2_OL_INACTIVE_L2 = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
+} QCow2MetadataOverlap;
+
+/* Perform all overlap checks which can be done in constant time */
+#define QCOW2_OL_CONSTANT \
+ (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
+ QCOW2_OL_SNAPSHOT_TABLE)
+
+/* Perform all overlap checks which don't require disk access */
+#define QCOW2_OL_CACHED \
+ (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
+ QCOW2_OL_INACTIVE_L1)
+
+/* Perform all overlap checks */
+#define QCOW2_OL_ALL \
+ (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
+
+#define L1E_OFFSET_MASK 0x00fffffffffffe00ULL
+#define L2E_OFFSET_MASK 0x00fffffffffffe00ULL
+#define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
+
+#define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
+
+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 int64_t qcow2_vm_state_offset(BDRVQcowState *s)
+{
+ return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
+}
+
+static inline uint64_t qcow2_max_refcount_clusters(BDRVQcowState *s)
+{
+ return QCOW_MAX_REFTABLE_SIZE >> s->cluster_bits;
+}
+
+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);
+}
+
+static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2)
+{
+ return r1 > r2 ? r1 - r2 : r2 - r1;
+}
+
+// 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_mark_corrupt(BlockDriverState *bs);
+int qcow2_mark_consistent(BlockDriverState *bs);
+int qcow2_update_header(BlockDriverState *bs);
+
+void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
+ int64_t size, const char *message_format, ...)
+ GCC_FMT_ATTR(5, 6);
+
+/* qcow2-refcount.c functions */
+int qcow2_refcount_init(BlockDriverState *bs);
+void qcow2_refcount_close(BlockDriverState *bs);
+
+int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index,
+ uint64_t *refcount);
+
+int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
+ uint64_t addend, bool decrease,
+ enum qcow2_discard_type type);
+
+int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_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);
+
+void qcow2_process_discards(BlockDriverState *bs, int ret);
+
+int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
+ int64_t size);
+int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
+ int64_t size);
+
+/* qcow2-cluster.c functions */
+int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
+ bool exact_size);
+int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index);
+void qcow2_l2_cache_reset(BlockDriverState *bs);
+int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
+int qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+ uint8_t *out_buf, const uint8_t *in_buf,
+ int nb_sectors, bool enc, Error **errp);
+
+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 *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, enum qcow2_discard_type type, bool full_discard);
+int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors);
+
+int qcow2_expand_zero_clusters(BlockDriverState *bs,
+ BlockDriverAmendStatusCB *status_cb);
+
+/* 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,
+ const char *name,
+ Error **errp);
+int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
+int qcow2_snapshot_load_tmp(BlockDriverState *bs,
+ const char *snapshot_id,
+ const char *name,
+ Error **errp);
+
+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(BlockDriverState *bs, 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_empty(BlockDriverState *bs, 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);
+void qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
+
+#endif