block: add queue flag for paravirt frontend drivers
authorFernando Luis Vázquez Cao <fernando@oss.ntt.co.jp>
Mon, 27 Oct 2008 09:44:46 +0000 (18:44 +0900)
committerJens Axboe <jens.axboe@oracle.com>
Mon, 29 Dec 2008 07:28:41 +0000 (08:28 +0100)
commit88e740f1654bf28565edd528a060695c1f2b5ad7
treec66a57396c9b881df1734f5b46e6681bc536c132
parent3c92ec8ae91ecf59d88c798301833d7cf83f2179
block: add queue flag for paravirt frontend drivers

As is the case with SSD devices, we do not want to idle in AS/CFQ when
the block device is a paravirt front-end driver. This patch adds a flag
(QUEUE_FLAG_VIRT) which should be used by front-end drivers such as
virtio_blk and xen-blkfront to indicate a paravirtualized device.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
include/linux/blkdev.h