#ifndef BLOCK_QCOW2_H
#define BLOCK_QCOW2_H
-#include "aes.h"
-#include "qemu-coroutine.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_VERSION 2
#define QCOW_CRYPT_NONE 0
#define QCOW_CRYPT_AES 1
#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 DEFAULT_CLUSTER_SIZE 65536
+
+#define QCOW2_OPT_LAZY_REFCOUNTS "lazy_refcounts"
+
typedef struct QCowHeader {
uint32_t magic;
uint32_t version;
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 {
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;
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,
+};
+
+typedef struct Qcow2Feature {
+ uint8_t type;
+ uint8_t bit;
+ char name[46];
+} QEMU_PACKED Qcow2Feature;
+
typedef struct BDRVQcowState {
int cluster_bits;
int cluster_size;
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;
struct QCowAIOCB;
-/* XXX This could be private for qcow2-cluster.c */
+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;
- uint64_t cluster_offset;
- int n_start;
+
+ /** 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 int size_to_l1(BDRVQcowState *s, int64_t size)
+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_update_snapshot_refcount(BlockDriverState *bs,
int64_t l1_table_offset, int l1_size, int addend);
-int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res);
+int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
+ BdrvCheckMode fix);
/* qcow2-cluster.c functions */
-int qcow2_grow_l1_table(BlockDriverState *bs, int min_size, bool exact_size);
+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,
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, QCowL2Meta *m);
+ 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_read_snapshots(BlockDriverState *bs);
/* qcow2-cache.c functions */
-Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables,
- bool writethrough);
+Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables);
int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);
-bool qcow2_cache_set_writethrough(BlockDriverState *bs, Qcow2Cache *c,
- bool enable);
void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
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