block: introduce new dirty bitmap functionality

Assert that write_compressed is never used with the dirty bitmap.
Setting the bits early is wrong, because a coroutine might concurrently
examine them and copy incomplete data from the source.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/block.h b/block.h
index 096fa09373..27b8f80bc6 100644
--- a/block.h
+++ b/block.h
@@ -353,8 +353,9 @@ void *qemu_blockalign(BlockDriverState *bs, size_t size);
 
 void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable);
 int bdrv_get_dirty(BlockDriverState *bs, int64_t sector);
-void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
-                      int nr_sectors);
+void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors);
+void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors);
+int64_t bdrv_get_next_dirty(BlockDriverState *bs, int64_t sector);
 int64_t bdrv_get_dirty_count(BlockDriverState *bs);
 
 void bdrv_enable_copy_on_read(BlockDriverState *bs);