tree 40fc70111217d23bbb5453fe08214d28ed4c7713
parent 0f3942a39ed768c967cb71ea0e9be7fc94112713
author Mike Snitzer <snitzer@redhat.com> 1273561062 +0200
committer Jens Axboe <jens.axboe@oracle.com> 1273561062 +0200

block: allow initialization of previously allocated request_queue

blk_init_queue() allocates the request_queue structure and then
initializes it as needed (request_fn, elevator, etc).

Split initialization out to blk_init_allocated_queue_node.
Introduce blk_init_allocated_queue wrapper function to model existing
blk_init_queue and blk_init_queue_node interfaces.

Export elv_register_queue to allow a newly added elevator to be
registered with sysfs.  Export elv_unregister_queue for symmetry.

These changes allow DM to initialize a device's request_queue with more
precision.  In particular, DM no longer unconditionally initializes a
full request_queue (elevator et al).  It only does so for a
request-based DM device.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>