diff options
Diffstat (limited to 'block/qcow2.h')
| -rw-r--r-- | block/qcow2.h | 123 |
1 files changed, 112 insertions, 11 deletions
diff --git a/block/qcow2.h b/block/qcow2.h index b4eb65470..dba977141 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -25,8 +25,8 @@ #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 @@ -58,6 +58,12 @@ #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" + typedef struct QCowHeader { uint32_t magic; uint32_t version; @@ -126,12 +132,28 @@ enum { 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 struct BDRVQcowState { int cluster_bits; int cluster_size; @@ -173,6 +195,9 @@ typedef struct BDRVQcowState { int flags; int qcow_version; + bool use_lazy_refcounts; + + bool discard_passthrough[QCOW2_DISCARD_MAX]; uint64_t incompatible_features; uint64_t compatible_features; @@ -181,6 +206,8 @@ typedef struct BDRVQcowState { size_t unknown_header_fields_size; void* unknown_header_fields; QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext; + QTAILQ_HEAD (, Qcow2DiscardRegion) discards; + bool cache_discards; } BDRVQcowState; /* XXX: use std qcow open function ? */ @@ -196,17 +223,59 @@ typedef struct QCowCreateState { 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; + + /** Host offset of the first newly allocated cluster */ uint64_t alloc_offset; - int n_start; + + /** + * 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; @@ -223,17 +292,32 @@ enum { #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); @@ -259,11 +343,24 @@ 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 */ @@ -275,9 +372,10 @@ 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); -void qcow2_free_any_clusters(BlockDriverState *bs, - uint64_t cluster_offset, int nb_clusters); + 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); @@ -285,8 +383,11 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); +void qcow2_process_discards(BlockDriverState *bs, int ret); + /* 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, @@ -297,7 +398,7 @@ 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); |