block: loop: introduce ioctl command of LOOP_SET_DIRECT_IO
authorMing Lei <ming.lei@canonical.com>
Mon, 17 Aug 2015 02:31:50 +0000 (10:31 +0800)
committerJens Axboe <axboe@fb.com>
Wed, 23 Sep 2015 17:01:16 +0000 (11:01 -0600)
commitab1cb278bc7027663adbfb0b81404f8398437e11
tree9406e09aeb44e5caa2ee816a93124f966812f4f5
parent2e5ab5f379f96a6207c45be40c357ebb1beb8ef3
block: loop: introduce ioctl command of LOOP_SET_DIRECT_IO

If loop block is mounted via 'mount -o loop', it isn't easy
to pass file descriptor opened as O_DIRECT, so this patch
introduces a new command to support direct IO for this case.

Cc: linux-api@vger.kernel.org
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
drivers/block/loop.c
include/uapi/linux/loop.h