Linux-libre 4.8.2-gnupck-4.8.2-gnu

1 files changed, 13 insertions, 0 deletions

diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 6e6cb0c9d..26c155bb6 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -149,6 +149,19 @@ static inline bool virtio_has_feature(const struct virtio_device *vdev,
 	return __virtio_test_bit(vdev, fbit);
 }
 
+/**
+ * virtio_has_iommu_quirk - determine whether this device has the iommu quirk
+ * @vdev: the device
+ */
+static inline bool virtio_has_iommu_quirk(const struct virtio_device *vdev)
+{
+	/*
+	 * Note the reverse polarity of the quirk feature (compared to most
+	 * other features), this is for compatibility with legacy systems.
+	 */
+	return !virtio_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
+}
+
 static inline
 struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev,
 					vq_callback_t *c, const char *n)