block/dirty-bitmap: add bdrv_dirty_bitmap_merge_internal

I'm surprised it didn't come up sooner, but sometimes we have a +busy
bitmap as a source. This is dangerous from the QMP API, but if we are
the owner that marked the bitmap busy, it's safe to merge it using it as
a read only source.

It is not safe in the general case to allow users to read from in-use
bitmaps, so create an internal variant that foregoes the safety
checking.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-10-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
This commit is contained in:
John Snow 2019-07-29 16:35:53 -04:00
parent c5b40c1f9c
commit b7661ca5d8
2 changed files with 54 additions and 7 deletions

View file

@ -1253,6 +1253,9 @@ void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes);
void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
void bdrv_restore_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *backup);
bool bdrv_dirty_bitmap_merge_internal(BdrvDirtyBitmap *dest,
const BdrvDirtyBitmap *src,
HBitmap **backup, bool lock);
void bdrv_inc_in_flight(BlockDriverState *bs);
void bdrv_dec_in_flight(BlockDriverState *bs);