On Sat, May 31, 2014 at 08:43:11PM +0200, Max Reitz wrote:
If a long-running operation on a BDS wants to always remain in the same
AIO context, it somehow needs to keep track of the BDS changing its
context. This adds a function for registering callbacks on a BDS which
are called whenever the BDS is attached or detached from an AIO context.
Signed-off-by: Max Reitz <address@hidden>
---
block.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++
include/block/block_int.h | 40 ++++++++++++++++++++++++++++++++++
2 files changed, 95 insertions(+)
Great, we definitely need this mechanism. Block jobs can also use it
later.
Usually QEMU calls this a "notifier" rather than a "follower". For
example, see include/qemu/notifier.h and bdrv_add_close_notifier().