From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Introduce a new function, acpi_get_data_full(), working in analogy
with acpi_get_data() except that it can execute a callback provided
as its 4th argument right after acpi_ns_get_attached_data() has
returned a success.
That will allow Linux to reference count the object pointed to by
*data before the namespace mutex is released so as to ensure that it
will not be freed going forward until the reference to it acquired
by acpi_get_data_full() is dropped.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Tested-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
---
drivers/acpi/acpica/nsxfeval.c | 33 ++++++++++++++++++++++++++++++---
include/acpi/acpixf.h | 4 ++++
2 files changed, 34 insertions(+), 3 deletions(-)
Index: linux-pm/drivers/acpi/acpica/nsxfeval.c
===================================================================
--- linux-pm.orig/drivers/acpi/acpica/nsxfeval.c
+++ linux-pm/drivers/acpi/acpica/nsxfeval.c
@@ -923,19 +923,22 @@ ACPI_EXPORT_SYMBOL(acpi_detach_data)
/*******************************************************************************
*
- * FUNCTION: acpi_get_data
+ * FUNCTION: acpi_get_data_full
*
* PARAMETERS: obj_handle - Namespace node
* handler - Handler used in call to attach_data
* data - Where the data is returned
+ * callback - function to execute before returning
*
* RETURN: Status
*
- * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
+ * DESCRIPTION: Retrieve data that was previously attached to a namespace node
+ * and execute a callback before returning.
*
******************************************************************************/
acpi_status
-acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
+acpi_get_data_full(acpi_handle obj_handle, acpi_object_handler handler,
+ void **data, void (*callback)(void *))
{
struct acpi_namespace_node *node;
acpi_status status;
@@ -960,10 +963,34 @@ acpi_get_data(acpi_handle obj_handle, ac
}
status = acpi_ns_get_attached_data(node, handler, data);
+ if (ACPI_SUCCESS(status) && callback) {
+ callback(*data);
+ }
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return (status);
}
+ACPI_EXPORT_SYMBOL(acpi_get_data_full)
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_get_data
+ *
+ * PARAMETERS: obj_handle - Namespace node
+ * handler - Handler used in call to attach_data
+ * data - Where the data is returned
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
+ *
+ ******************************************************************************/
+acpi_status
+acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
+{
+ return acpi_get_data_full(obj_handle, handler, data, NULL);
+}
+
ACPI_EXPORT_SYMBOL(acpi_get_data)
Index: linux-pm/include/acpi/acpixf.h
===================================================================
--- linux-pm.orig/include/acpi/acpixf.h
+++ linux-pm/include/acpi/acpixf.h
@@ -230,6 +230,10 @@ acpi_attach_data(acpi_handle object, acp
acpi_status acpi_detach_data(acpi_handle object, acpi_object_handler handler);
acpi_status
+acpi_get_data_full(acpi_handle object, acpi_object_handler handler, void **data,
+ void (*callback)(void *));
+
+acpi_status
acpi_get_data(acpi_handle object, acpi_object_handler handler, void **data);
acpi_status
--
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