BlockDriverState lifecycle management is needed by future features such as image fleecing and blockdev-add. This series adds reference count to BlockDriverState.
The first two patches clean up two odd BlockDriverState use cases, so all code uses bdrv_new() to create BlockDriverState instance. Then implemented bdrv_ref() and bdrv_unref() to operate on refcnt: Initially, refcnt is 1, which means bdrv_unref is effectively a bdrv_delete() here. So patch 04 has a search and replace to convert bdrv_delete to bdrv_unref, before bdrv_ref is used anywhere. 05~08 patches calls bdrv_ref for device attach, block-migration and nbd. The rule is: Either bdrv_ref() or bdrv_new() must have a matching bdrv_unref() call, and the last matching bdrv_unref deletes the bs. Fam Zheng (8): vvfat: use bdrv_new() to allocate BlockDriverState iscsi: use bdrv_new() instead of stack structure block: implement reference count for BlockDriverState block: make bdrv_delete() static block: use BlockDriverState refcnt for device attach/detach migration: omit drive ref as we have bdrv_ref now xen_disk: simplify blk_disconnect with refcnt nbd: use BlockDriverState refcnt block-migration.c | 4 ++-- block.c | 52 ++++++++++++++++++++++++++++++++++++----------- block/backup.c | 2 +- block/blkverify.c | 4 ++-- block/cow.c | 2 +- block/iscsi.c | 14 ++++++------- block/mirror.c | 2 +- block/qcow.c | 2 +- block/qcow2.c | 2 +- block/qed.c | 2 +- block/sheepdog.c | 6 +++--- block/snapshot.c | 2 +- block/stream.c | 2 +- block/vmdk.c | 10 ++++----- block/vvfat.c | 6 +++--- blockdev-nbd.c | 10 +-------- blockdev.c | 14 ++++++------- hw/block/xen_disk.c | 9 ++------ include/block/block.h | 3 ++- include/block/block_int.h | 1 + nbd.c | 5 +++++ qemu-img.c | 26 ++++++++++++------------ qemu-io.c | 6 +++--- 23 files changed, 104 insertions(+), 82 deletions(-) -- 1.8.3.2
