[dm-devel] [RFC PATCH 1/2] block: allow initialization of previously allocated request_queue

[Jens Axboe]

On Mon, May 10 2010, Mike Snitzer wrote:
> 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.

Looks good, I'll apply this. I don't think the exports need to be _GPL
in this case, generally I've only done that with the exports for hooking
in a new IO scheduler.

-- 
Jens Axboe