diff options
Diffstat (limited to 'drivers/of/overlay.c')
| -rw-r--r-- | drivers/of/overlay.c | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index b35fe88f1851..7baa53e5b1d7 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -102,12 +102,28 @@ static DEFINE_IDR(ovcs_idr); static BLOCKING_NOTIFIER_HEAD(overlay_notify_chain); +/** + * of_overlay_notifier_register() - Register notifier for overlay operations + * @nb: Notifier block to register + * + * Register for notification on overlay operations on device tree nodes. The + * reported actions definied by @of_reconfig_change. The notifier callback + * furthermore receives a pointer to the affected device tree node. + * + * Note that a notifier callback is not supposed to store pointers to a device + * tree node or its content beyond @OF_OVERLAY_POST_REMOVE corresponding to the + * respective node it received. + */ int of_overlay_notifier_register(struct notifier_block *nb) { return blocking_notifier_chain_register(&overlay_notify_chain, nb); } EXPORT_SYMBOL_GPL(of_overlay_notifier_register); +/** + * of_overlay_notifier_register() - Unregister notifier for overlay operations + * @nb: Notifier block to unregister + */ int of_overlay_notifier_unregister(struct notifier_block *nb) { return blocking_notifier_chain_unregister(&overlay_notify_chain, nb); @@ -671,17 +687,13 @@ static void free_overlay_changeset(struct overlay_changeset *ovcs) of_node_put(ovcs->fragments[i].overlay); } kfree(ovcs->fragments); - /* - * TODO - * - * would like to: kfree(ovcs->overlay_tree); - * but can not since drivers may have pointers into this data - * - * would like to: kfree(ovcs->fdt); - * but can not since drivers may have pointers into this data + * There should be no live pointers into ovcs->overlay_tree and + * ovcs->fdt due to the policy that overlay notifiers are not allowed + * to retain pointers into the overlay devicetree. */ - + kfree(ovcs->overlay_tree); + kfree(ovcs->fdt); kfree(ovcs); } |