[Qemu-devel] [PATCH 0/3] block: per caller dirty bitmap

[Fam Zheng]

Previously a BlockDriverState has only one dirty bitmap (bs->dirty_bitmap),
consequently only one caller can keep track of writings with it. This limit is
removed by this series. This is useful for implementing features like
incremental backup, which may require multiple dirty bitmap callers for one BDS.

The bs->dirty_bitmap is changed to QLIST of HBitmap as bs->dirty_bitmaps, while
still maintained by block.c. The caller calls bdrv_create_dirty_bitmap() to
allocate a dirty bitmap and releases it after use by
bdrv_release_dirty_bitmap(). Block.c automatically sets dirty bits just like
existing code, but to all the dirty bitmaps in the BDS. That way the caller
doesn't need to register a callback and update dirty bit explicitly.

Fam Zheng (3):
  HBitmap: move struct HBitmap to header
  HBitmap: add QLIST_ENTRY to HBitmap
  block: per caller dirty bitmap

 block-migration.c         | 22 ++++++++++----
 block.c                   | 74 ++++++++++++++++++++++++++---------------------
 block/mirror.c            | 23 ++++++++-------
 block/qapi.c              |  8 -----
 include/block/block.h     | 11 ++++---
 include/block/block_int.h |  2 +-
 include/qemu/hbitmap.h    | 42 +++++++++++++++++++++++++++
 util/hbitmap.c            | 38 ------------------------
 8 files changed, 120 insertions(+), 100 deletions(-)

-- 
1.8.3.1