From 48e4043d4529523cbc7fa8dd745bd8e2c45ce1d3 Mon Sep 17 00:00:00 2001 From: Ryan Harper Date: Wed, 16 Apr 2008 13:56:37 -0500 Subject: [PATCH] virtio: add virtio disk geometry feature Rather than faking up some geometry, allow the backend to push the disk geometry via virtio pci config option. Keep the old geo code around for compatibility. Signed-off-by: Ryan Harper Reviewed-by: Anthony Liguori Signed-off-by: Rusty Russell (modified to single struct) --- drivers/block/virtio_blk.c | 24 ++++++++++++++++++++---- include/linux/virtio_blk.h | 7 +++++++ 2 files changed, 27 insertions(+), 4 deletions(-) diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 78be6b8c89..84e064ffee 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -157,10 +157,25 @@ static int virtblk_ioctl(struct inode *inode, struct file *filp, /* We provide getgeo only to please some old bootloader/partitioning tools */ static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo) { - /* some standard values, similar to sd */ - geo->heads = 1 << 6; - geo->sectors = 1 << 5; - geo->cylinders = get_capacity(bd->bd_disk) >> 11; + struct virtio_blk *vblk = bd->bd_disk->private_data; + struct virtio_blk_geometry vgeo; + int err; + + /* see if the host passed in geometry config */ + err = virtio_config_val(vblk->vdev, VIRTIO_BLK_F_GEOMETRY, + offsetof(struct virtio_blk_config, geometry), + &vgeo); + + if (!err) { + geo->heads = vgeo.heads; + geo->sectors = vgeo.sectors; + geo->cylinders = vgeo.cylinders; + } else { + /* some standard values, similar to sd */ + geo->heads = 1 << 6; + geo->sectors = 1 << 5; + geo->cylinders = get_capacity(bd->bd_disk) >> 11; + } return 0; } @@ -310,6 +325,7 @@ static 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, }; static struct virtio_driver virtio_blk = { diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index c75a9e82b9..d4695a3356 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -9,6 +9,7 @@ #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ #define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ #define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ +#define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */ struct virtio_blk_config { @@ -18,6 +19,12 @@ struct virtio_blk_config __le32 size_max; /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */ __le32 seg_max; + /* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */ + struct virtio_blk_geometry { + __le16 cylinders; + __u8 heads; + __u8 sectors; + } geometry; } __attribute__((packed)); /* These two define direction. */ -- 2.39.5