This series converts all I/O function in the core block layer up to bdrv_co_preadv/pwritev() to taking a BdrvChild as their first parameter instead of a BlockDriverState.
The original motivation for this change were op blockers, where one of the biggest problems is making sure that every user of block devices actually registers correctly with the op blockers system. If the I/O functions know which parent a request comes from (BdrvChild basically corresponds to an edge in our block device graph), it can use assertions to make sure that that parent has actually registered its activities and thereby ensured that it doesn't conflict with other users. There are, however, more benefits we get from this change. The most important one is probably that it enforces important aspects of the block layer design like that external users go through a BlockBackend and request are internally routed along the edges of the graph. Accesses to random BDSes are no longer possible, you need to own an actual child reference so you can make a request. The work on this series already led to a few cleanups and BlockBackend conversions in master, and this series contains a few more. As a bonus, all the block drivers using bs->file->bs everywhere can now go back to bs->file, which is a little nicer to read. Kevin Wolf (17): vvfat: Use BdrvChild for s->qcow blkreplay: Convert to byte-based I/O vhdx: Some more BlockBackend use in vhdx_create() block: Convert bdrv_co_readv() to BdrvChild block: Convert bdrv_co_writev() to BdrvChild block: Convert bdrv_aio_readv() to BdrvChild block: Convert bdrv_aio_writev() to BdrvChild block: Convert bdrv_co_do_readv/writev to BdrvChild block: Move bdrv_commit() to block/commit.c block: Use BlockBackend for I/O in bdrv_commit() block: Convert bdrv_read() to BdrvChild block: Convert bdrv_write() to BdrvChild block: Convert bdrv_pread(v) to BdrvChild block: Convert bdrv_pwrite(v/_sync) to BdrvChild block: Convert bdrv_pwrite_zeroes() to BdrvChild block: Convert bdrv_prwv_co() to BdrvChild block: Convert bdrv_co_preadv/pwritev to BdrvChild block.c | 117 ++---------------------------------- block/Makefile.objs | 3 +- block/blkdebug.c | 4 +- block/blkreplay.c | 18 +++--- block/blkverify.c | 8 +-- block/block-backend.c | 9 ++- block/bochs.c | 8 +-- block/cloop.c | 8 +-- block/commit.c | 121 +++++++++++++++++++++++++++++++++++++ block/crypto.c | 6 +- block/dmg.c | 21 +++---- block/io.c | 132 ++++++++++++++++++++++------------------- block/parallels.c | 16 ++--- block/qcow.c | 41 +++++++------ block/qcow2-cache.c | 4 +- block/qcow2-cluster.c | 18 +++--- block/qcow2-refcount.c | 36 +++++------ block/qcow2-snapshot.c | 26 ++++---- block/qcow2.c | 50 +++++++++------- block/qed-table.c | 4 +- block/qed.c | 22 +++---- block/quorum.c | 8 +-- block/raw_bsd.c | 6 +- block/vdi.c | 14 ++--- block/vhdx-log.c | 12 ++-- block/vhdx.c | 85 ++++++++++++++------------ block/vmdk.c | 54 ++++++++--------- block/vpc.c | 24 ++++---- block/vvfat.c | 61 ++++++++++++------- include/block/block.h | 38 ++++++------ include/block/block_int.h | 4 +- include/sysemu/block-backend.h | 1 + qemu-img.c | 2 +- 33 files changed, 522 insertions(+), 459 deletions(-) -- 1.8.3.1
