virtio: use size-based config accessors.

This lets the transport do endian conversion if necessary, and insulates
the drivers from the difference.

Most drivers can use the simple helpers virtio_cread() and virtio_cwrite().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 4 insertions, 5 deletions

diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index 990afab2be1b..9c5a1aa34d12 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -544,9 +544,7 @@ static int p9_virtio_probe(struct virtio_device *vdev)
 
         chan->inuse = false;
         if (virtio_has_feature(vdev, VIRTIO_9P_MOUNT_TAG)) {
-                vdev->config->get(vdev,
-                                offsetof(struct virtio_9p_config, tag_len),
-                                &tag_len, sizeof(tag_len));
+                virtio_cread(vdev, struct virtio_9p_config, tag_len, &tag_len);
         } else {
                 err = -EINVAL;
                 goto out_free_vq;
@@ -556,8 +554,9 @@ static int p9_virtio_probe(struct virtio_device *vdev)
                 err = -ENOMEM;
                 goto out_free_vq;
         }
-        vdev->config->get(vdev, offsetof(struct virtio_9p_config, tag),
-                        tag, tag_len);
+
+        virtio_cread_bytes(vdev, offsetof(struct virtio_9p_config, tag),
+                           tag, tag_len);
         chan->tag = tag;
         chan->tag_len = tag_len;
         err = sysfs_create_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr);