remoteproc: core: Introduce rproc_add_rvdev function

The rproc structure contains a list of registered rproc_vdev structure.
To be able to move the management of the rproc_vdev structure in
remoteproc_virtio.c (i.e rproc_rvdev_add_device function),
introduce the rproc_add_rvdev and rproc_remove_rvdev functions.
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20220921135044.917140-3-arnaud.pouliquen@foss.st.comSigned-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

drivers/remoteproc/remoteproc_core.c

@@ -486,6 +486,18 @@ static int copy_dma_range_map(struct device *to, struct device *from)
 	return 0;
 }
 
+static void rproc_add_rvdev(struct rproc *rproc, struct rproc_vdev *rvdev)
+{
+	if (rvdev && rproc)
+		list_add_tail(&rvdev->node, &rproc->rvdevs);
+}
+
+static void rproc_remove_rvdev(struct rproc_vdev *rvdev)
+{
+	if (rvdev)
+		list_del(&rvdev->node);
+}
+
 static struct rproc_vdev *
 rproc_rvdev_add_device(struct rproc *rproc, struct rproc_vdev_data *rvdev_data)
 {
@@ -549,7 +561,7 @@ rproc_rvdev_add_device(struct rproc *rproc, struct rproc_vdev_data *rvdev_data)
 			goto unwind_vring_allocations;
 	}
 
-	list_add_tail(&rvdev->node, &rproc->rvdevs);
+	rproc_add_rvdev(rproc, rvdev);
 
 	rvdev->subdev.start = rproc_vdev_do_start;
 	rvdev->subdev.stop = rproc_vdev_do_stop;
@@ -579,7 +591,7 @@ void rproc_vdev_release(struct kref *ref)
 	}
 
 	rproc_remove_subdev(rproc, &rvdev->subdev);
-	list_del(&rvdev->node);
+	rproc_remove_rvdev(rvdev);
 	device_unregister(&rvdev->dev);
 }