Name

blk_queue_ordered — does this queue support ordered writes

Synopsis

int blk_queue_ordered (struct request_queue * q,
 unsigned ordered,
 prepare_flush_fn * prepare_flush_fn);
 

Arguments

q

the request queue

ordered

one of QUEUE_ORDERED_*

prepare_flush_fn

rq setup helper for cache flush ordered writes

Description

For journalled file systems, doing ordered writes on a commit block instead of explicitly doing wait_on_buffer (which is bad for performance) can be a big win. Block drivers supporting this feature should call this function and indicate so.