From 7d82410950aa74adccf035c332e409af2bb93e92 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Fri, 24 Apr 2015 14:26:24 +0200 Subject: virtio: add explicit big-endian support to memory accessors The current memory accessors logic is: - little endian if little_endian - native endian (i.e. no byteswap) if !little_endian If we want to fully support cross-endian vhost, we also need to be able to convert to big endian. Instead of changing the little_endian argument to some 3-value enum, this patch changes the logic to: - little endian if little_endian - big endian if !little_endian The native endian case is handled by all users with a trivial helper. This patch doesn't change any functionality, nor it does add overhead. Signed-off-by: Greg Kurz Signed-off-by: Michael S. Tsirkin Reviewed-by: Cornelia Huck Reviewed-by: David Gibson --- include/linux/virtio_config.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux/virtio_config.h') diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 170947eb11b5..e5ce8ab0b8b0 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -207,7 +207,8 @@ int virtqueue_set_affinity(struct virtqueue *vq, int cpu) static inline bool virtio_is_little_endian(struct virtio_device *vdev) { - return virtio_has_feature(vdev, VIRTIO_F_VERSION_1); + return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) || + virtio_legacy_is_little_endian(); } /* Memory accessors */ -- cgit v1.2.3