• Jeff Dike's avatar
    [PATCH] uml: add host AIO support to block driver · 09ace81c
    Jeff Dike authored
    This adds AIO support to the ubd driver.
    
    The driver breaks a struct request into IO requests to the host, based on the
    hardware segments in the request and on any COW blocks covered by the request.
    
    The ubd IO thread is gone, since there is now an equivalent thread in the AIO
    module.
    
    There is provision for multiple outstanding requests now.  Requests aren't
    retired until all pieces of it have been completed.  The AIO requests have a
    shared count, which is decremented as IO operations come in until it reaches
    0.  This can be possibly moved to the request struct - haven't looked at this
    yet.
    Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    09ace81c
aio.c 11.2 KB