[PATCH 15/30] virtio_blk: drop REQ_HARDBARRIER support

Remove now unused REQ_HARDBARRIER support. virtio_blk already
supports REQ_FLUSH and the usefulness of REQ_FUA for virtio_blk is
questionable at this point, so there's nothing else to do to support
new REQ_FLUSH/FUA interface.

Signed-off-by: Tejun Heo <tj [at] kernel.org>
Cc: Michael S. Tsirkin <mst [at] redhat.com>
Cc: Christoph Hellwig <hch [at] lst.de>
---
drivers/block/virtio_blk.c | 17 ++++-------------
1 files changed, 4 insertions(+), 13 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index d10b635..1260628 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
[at] [at] -128,9 +128,6 [at] [at] static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
}
}

- if (vbr->req->cmd_flags & REQ_HARDBARRIER)
- vbr->out_hdr.type |= VIRTIO_BLK_T_BARRIER;
-
sg_set_buf(&vblk->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));

/*
[at] [at] -388,13 +385,7 [at] [at] static int __devinit virtblk_probe(struct virtio_device *vdev)
vblk->disk->driverfs_dev = &vdev->dev;
index++;

- /*
- * If the FLUSH feature is supported we do have support for
- * flushing a volatile write cache on the host. Use that to
- * implement write barrier support; otherwise, we must assume
- * that the host does not perform any kind of volatile write
- * caching.
- */
+ /* configure queue flush support */
if (virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH))
blk_queue_flush(q, REQ_FLUSH);

[at] [at] -515,9 +506,9 [at] [at] static const struct virtio_device_id id_table[] = {
};

static unsigned int features[] = {
- VIRTIO_BLK_F_BARRIER, VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX,
- VIRTIO_BLK_F_GEOMETRY, VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE,
- VIRTIO_BLK_F_SCSI, VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY
+ VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
+ VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, VIRTIO_BLK_F_SCSI,
+ VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY
};

/*
--
1.7.1
Tejun Heo [ Mi, 25 August 2010 17:47 ] [ ID #2046615 ]
Linux » gmane.linux.raid » [PATCH 15/30] virtio_blk: drop REQ_HARDBARRIER support

Vorheriges Thema: [PATCH 16/30] lguest: replace VIRTIO_F_BARRIER support with VIRTIO_F_FLUSH support
Nächstes Thema: [PATCH 13/30] block: simplify queue_next_fseq