int err;
u64 cap;
u32 v;
+ u32 blk_size;
if (index_to_minor(index) >= 1 << MINORBITS)
return -ENOSPC;
if (!err)
blk_queue_max_hw_segments(vblk->disk->queue, v);
+ /* Host can optionally specify the block size of the device */
+ err = virtio_config_val(vdev, VIRTIO_BLK_F_BLK_SIZE,
+ offsetof(struct virtio_blk_config, blk_size),
+ &blk_size);
+ if (!err)
+ blk_queue_hardsect_size(vblk->disk->queue, blk_size);
+
add_disk(vblk->disk);
return 0;
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_GEOMETRY, VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE,
};
static struct virtio_driver virtio_blk = {
#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
{
__u8 heads;
__u8 sectors;
} geometry;
+ /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
+ __u32 blk_size;
} __attribute__((packed));
/* These two define direction. */