The blkdebug block driver is undocumented. Documenting it is worthwhile
since it offers powerful error injection features that are used by
qemu-iotests test cases.
This document will make it easier for people to learn about and use
blkdebug.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
