qemu/include/block/dirty-bitmap.h
Eric Blake 1b6cc579de dirty-bitmap: Avoid size query failure during truncate
We've previously fixed several places where we failed to account
for possible errors from bdrv_nb_sectors().  Fix another one by
making bdrv_dirty_bitmap_truncate() take the new size from the
caller instead of querying itself; then adjust the sole caller
bdrv_truncate() to pass the size just determined by a successful
resize, or to reuse the size given to the original truncate
operation when refresh_total_sectors() was not able to confirm the
actual size (the two sizes can potentially differ according to
rounding constraints), thus avoiding sizing the bitmaps to -1.
This also fixes a bug where not all failure paths in
bdrv_truncate() would set errp.

Note that bdrv_truncate() is still a bit awkward.  We may want
to revisit it later and clean up things to better guarantee that
a resize attempt either fails cleanly up front, or cannot fail
after guest-visible changes have been made (if temporary changes
are made, then they need to be cleanly rolled back).  But that
is a task for another day; for now, the goal is the bare minimum
fix to ensure that just bdrv_dirty_bitmap_truncate() cannot fail.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06 16:28:58 +02:00

96 lines
5.4 KiB
C

#ifndef BLOCK_DIRTY_BITMAP_H
#define BLOCK_DIRTY_BITMAP_H
#include "qemu-common.h"
#include "qemu/hbitmap.h"
BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
uint32_t granularity,
const char *name,
Error **errp);
void bdrv_create_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap,
int chunk_size);
void bdrv_release_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap);
int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
BdrvDirtyBitmap *bitmap,
Error **errp);
BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState *bs,
BdrvDirtyBitmap *bitmap,
Error **errp);
BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
BdrvDirtyBitmap *bitmap,
Error **errp);
BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
const char *name);
void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap);
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
void bdrv_release_named_dirty_bitmaps(BlockDriverState *bs);
void bdrv_release_persistent_dirty_bitmaps(BlockDriverState *bs);
void bdrv_remove_persistent_dirty_bitmap(BlockDriverState *bs,
const char *name,
Error **errp);
void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
uint32_t bdrv_dirty_bitmap_granularity(const BdrvDirtyBitmap *bitmap);
bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
const char *bdrv_dirty_bitmap_name(const BdrvDirtyBitmap *bitmap);
int64_t bdrv_dirty_bitmap_size(const BdrvDirtyBitmap *bitmap);
DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int64_t nr_sectors);
void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int64_t nr_sectors);
BdrvDirtyBitmapIter *bdrv_dirty_meta_iter_new(BdrvDirtyBitmap *bitmap);
BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
uint64_t first_sector);
void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter);
uint64_t bdrv_dirty_bitmap_serialization_size(const BdrvDirtyBitmap *bitmap,
uint64_t start, uint64_t count);
uint64_t bdrv_dirty_bitmap_serialization_align(const BdrvDirtyBitmap *bitmap);
void bdrv_dirty_bitmap_serialize_part(const BdrvDirtyBitmap *bitmap,
uint8_t *buf, uint64_t start,
uint64_t count);
void bdrv_dirty_bitmap_deserialize_part(BdrvDirtyBitmap *bitmap,
uint8_t *buf, uint64_t start,
uint64_t count, bool finish);
void bdrv_dirty_bitmap_deserialize_zeroes(BdrvDirtyBitmap *bitmap,
uint64_t start, uint64_t count,
bool finish);
void bdrv_dirty_bitmap_deserialize_ones(BdrvDirtyBitmap *bitmap,
uint64_t start, uint64_t count,
bool finish);
void bdrv_dirty_bitmap_deserialize_finish(BdrvDirtyBitmap *bitmap);
void bdrv_dirty_bitmap_set_readonly(BdrvDirtyBitmap *bitmap, bool value);
void bdrv_dirty_bitmap_set_autoload(BdrvDirtyBitmap *bitmap, bool autoload);
void bdrv_dirty_bitmap_set_persistance(BdrvDirtyBitmap *bitmap,
bool persistent);
/* Functions that require manual locking. */
void bdrv_dirty_bitmap_lock(BdrvDirtyBitmap *bitmap);
void bdrv_dirty_bitmap_unlock(BdrvDirtyBitmap *bitmap);
int bdrv_get_dirty_locked(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t sector);
void bdrv_set_dirty_bitmap_locked(BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int64_t nr_sectors);
void bdrv_reset_dirty_bitmap_locked(BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int64_t nr_sectors);
int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter);
void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *hbi, int64_t sector_num);
int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap);
int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap);
void bdrv_dirty_bitmap_truncate(BlockDriverState *bs, int64_t bytes);
bool bdrv_dirty_bitmap_readonly(const BdrvDirtyBitmap *bitmap);
bool bdrv_has_readonly_bitmaps(BlockDriverState *bs);
bool bdrv_dirty_bitmap_get_autoload(const BdrvDirtyBitmap *bitmap);
bool bdrv_dirty_bitmap_get_persistance(BdrvDirtyBitmap *bitmap);
bool bdrv_has_changed_persistent_bitmaps(BlockDriverState *bs);
BdrvDirtyBitmap *bdrv_dirty_bitmap_next(BlockDriverState *bs,
BdrvDirtyBitmap *bitmap);
char *bdrv_dirty_bitmap_sha256(const BdrvDirtyBitmap *bitmap, Error **errp);
#endif