From 066f4d82a67f621ddd547bfa4b9c94631d8457b0 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 29 May 2008 11:08:26 +0200 Subject: virtio_blk: check for hardsector size from host Currently virtio_blk assumes a 512 byte hard sector size. This can cause trouble / performance issues if the backing has a different block size (like a file on an ext3 file system formatted with 4k block size or a dasd). Lets add a feature flag that tells the guest to use a different hard sector size than 512 byte. Signed-off-by: Christian Borntraeger Signed-off-by: Rusty Russell --- include/linux/virtio_blk.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/virtio_blk.h') diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index 6a66c7f30bcb..c1aef85243bf 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -13,6 +13,7 @@ #define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ #define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */ #define VIRTIO_BLK_F_RO 5 /* Disk is read-only */ +#define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/ struct virtio_blk_config { @@ -28,6 +29,8 @@ struct virtio_blk_config __u8 heads; __u8 sectors; } geometry; + /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */ + __u32 blk_size; } __attribute__((packed)); /* These two define direction. */ -- cgit v1.2.3