Allow elevators to sort/merge discard requests
authorDavid Woodhouse <David.Woodhouse@intel.com>
Sat, 9 Aug 2008 15:42:20 +0000 (16:42 +0100)
committerJens Axboe <jens.axboe@oracle.com>
Thu, 9 Oct 2008 06:56:02 +0000 (08:56 +0200)
commite17fc0a1ccf88f6d4dcb363729f3141b0958c325
tree0a7c2dc1c3159c2af14d87c67ca83e158b2c78b5
parentd30a2605be9d5132d95944916e8f578fcfe4f976
Allow elevators to sort/merge discard requests

But blkdev_issue_discard() still emits requests which are interpreted as
soft barriers, because na├»ve callers might otherwise issue subsequent
writes to those same sectors, which might cross on the queue (if they're
reallocated quickly enough).

Callers still _can_ issue non-barrier discard requests, but they have to
take care of queue ordering for themselves.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
block/blk-barrier.c
block/blk-core.c
block/blk-merge.c
block/elevator.c
block/ioctl.c
include/linux/bio.h
include/linux/blkdev.h
include/linux/fs.h