Commit 2e57d10a authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

ACPI: utils: Dynamically determine acpi_handle_list size 

Address a long-standing "TBD" comment in the ACPI headers regarding the
number of handles in struct acpi_handle_list.

The number 10, which along with the comment dates back to 2.4.23, seems
like it may have been arbitrarily chosen and isn't sufficient in all
cases [1].

Finally change the code to dynamically determine the size of the handles
table in struct acpi_handle_list and allocate it accordingly.

Update the users of to struct acpi_handle_list to take the additional
dynamic allocation into account.

Link: https://lore.kernel.org/linux-acpi/20230809094451.15473-1-ivan.hu@canonical.com

 # [1]
Co-developed-by: default avatarVicki Pfau <vi@endrift.com>
Signed-off-by: default avatarVicki Pfau <vi@endrift.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 3e7d6f39

drivers/acpi/acpi_lpss.c

+7 −3
Original line number Diff line number Diff line
@@ -578,6 +578,7 @@ static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle) 
{

	struct acpi_handle_list dep_devices;

	acpi_status status;

	bool ret = false;

	int i;



	if (!acpi_has_method(adev->handle, "_DEP"))
@@ -591,11 +592,14 @@ static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle) 
	}



	for (i = 0; i < dep_devices.count; i++) {

		if (dep_devices.handles[i] == handle)

			return true;

		if (dep_devices.handles[i] == handle) {

			ret = true;

			break;

		}

	}



	return false;

	acpi_handle_list_free(&dep_devices);

	return ret;

}



static void acpi_lpss_link_consumer(struct device *dev1,

drivers/acpi/scan.c

+1 −0
Original line number Diff line number Diff line
@@ -2032,6 +2032,7 @@ static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep) 
		mutex_unlock(&acpi_dep_list_lock);

	}



	acpi_handle_list_free(&dep_devices);

	return count;

}

drivers/acpi/thermal.c

+21 −7
Original line number Diff line number Diff line
@@ -208,7 +208,7 @@ static bool update_trip_devices(struct acpi_thermal *tz, 
				struct acpi_thermal_trip *acpi_trip,

				int index, bool compare)

{

	struct acpi_handle_list devices;

	struct acpi_handle_list devices = { 0 };

	char method[] = "_PSL";

	acpi_status status;
@@ -218,18 +218,21 @@ static bool update_trip_devices(struct acpi_thermal *tz, 
		method[3] = '0' + index;

	}



	memset(&devices, 0, sizeof(devices));



	status = acpi_evaluate_reference(tz->device->handle, method, NULL, &devices);

	if (ACPI_FAILURE(status)) {

		acpi_handle_info(tz->device->handle, "%s evaluation failure\n", method);

		return false;

	}



	if (compare && memcmp(&acpi_trip->devices, &devices, sizeof(devices)))

	if (acpi_handle_list_equal(&acpi_trip->devices, &devices)) {

		acpi_handle_list_free(&devices);

		return true;

	}



	if (compare)

		ACPI_THERMAL_TRIPS_EXCEPTION(tz, "device");



	memcpy(&acpi_trip->devices, &devices, sizeof(devices));

	acpi_handle_list_replace(&acpi_trip->devices, &devices);

	return true;

}
@@ -842,6 +845,17 @@ static void acpi_thermal_check_fn(struct work_struct *work) 
	mutex_unlock(&tz->thermal_check_lock);

}



static void acpi_thermal_free_thermal_zone(struct acpi_thermal *tz)

{

	int i;



	acpi_handle_list_free(&tz->trips.passive.trip.devices);

	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)

		acpi_handle_list_free(&tz->trips.active[i].trip.devices);



	kfree(tz);

}



static int acpi_thermal_add(struct acpi_device *device)

{

	struct acpi_thermal_trip *acpi_trip;
@@ -968,7 +982,7 @@ static int acpi_thermal_add(struct acpi_device *device) 
free_trips:

	kfree(tz->trip_table);

free_memory:

	kfree(tz);

	acpi_thermal_free_thermal_zone(tz);



	return result;

}
@@ -988,7 +1002,7 @@ static void acpi_thermal_remove(struct acpi_device *device) 
	flush_workqueue(acpi_thermal_pm_queue);

	acpi_thermal_unregister_thermal_zone(tz);



	kfree(tz);

	acpi_thermal_free_thermal_zone(tz);

}



#ifdef CONFIG_PM_SLEEP

drivers/acpi/utils.c

+59 −2
Original line number Diff line number Diff line
@@ -370,7 +370,8 @@ acpi_evaluate_reference(acpi_handle handle, 
		goto end;

	}



	if (package->package.count > ACPI_MAX_HANDLES) {

	list->handles = kcalloc(package->package.count, sizeof(*list->handles), GFP_KERNEL);

	if (!list->handles) {

		kfree(package);

		return AE_NO_MEMORY;

	}
@@ -402,7 +403,8 @@ acpi_evaluate_reference(acpi_handle handle, 
      end:

	if (ACPI_FAILURE(status)) {

		list->count = 0;

		//kfree(list->handles);

		kfree(list->handles);

		list->handles = NULL;

	}



	kfree(buffer.pointer);
@@ -412,6 +414,61 @@ acpi_evaluate_reference(acpi_handle handle, 


EXPORT_SYMBOL(acpi_evaluate_reference);



/**

 * acpi_handle_list_equal - Check if two ACPI handle lists are the same

 * @list1: First list to compare.

 * @list2: Second list to compare.

 *

 * Return true if the given ACPI handle lists are of the same size and

 * contain the same ACPI handles in the same order.  Otherwise, return false.

 */

bool acpi_handle_list_equal(struct acpi_handle_list *list1,

			    struct acpi_handle_list *list2)

{

	return list1->count == list2->count &&

		!memcmp(list1->handles, list2->handles,

		        list1->count * sizeof(acpi_handle));

}

EXPORT_SYMBOL_GPL(acpi_handle_list_equal);



/**

 * acpi_handle_list_replace - Replace one ACPI handle list with another

 * @dst: ACPI handle list to replace.

 * @src: Source ACPI handle list.

 *

 * Free the handles table in @dst, move the handles table from @src to @dst,

 * copy count from @src to @dst and clear @src.

 */

void acpi_handle_list_replace(struct acpi_handle_list *dst,

			      struct acpi_handle_list *src)

{

	if (dst->count)

		kfree(dst->handles);



	dst->count = src->count;

	dst->handles = src->handles;



	src->handles = NULL;

	src->count = 0;

}

EXPORT_SYMBOL_GPL(acpi_handle_list_replace);



/**

 * acpi_handle_list_free - Free the handles table in an ACPI handle list

 * @list: ACPI handle list to free.

 *

 * Free the handles table in @list and clear its count field.

 */

void acpi_handle_list_free(struct acpi_handle_list *list)

{

	if (!list->count)

		return;



	kfree(list->handles);

	list->count = 0;

}

EXPORT_SYMBOL_GPL(acpi_handle_list_free);



acpi_status

acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)

{

drivers/platform/surface/surface_acpi_notify.c

+7 −3
Original line number Diff line number Diff line
@@ -741,6 +741,7 @@ static bool is_san_consumer(struct platform_device *pdev, acpi_handle handle) 
	struct acpi_handle_list dep_devices;

	acpi_handle supplier = ACPI_HANDLE(&pdev->dev);

	acpi_status status;

	bool ret = false;

	int i;



	if (!acpi_has_method(handle, "_DEP"))
@@ -753,11 +754,14 @@ static bool is_san_consumer(struct platform_device *pdev, acpi_handle handle) 
	}



	for (i = 0; i < dep_devices.count; i++) {

		if (dep_devices.handles[i] == supplier)

			return true;

		if (dep_devices.handles[i] == supplier) {

			ret = true;

			break;

		}

	}



	return false;

	acpi_handle_list_free(&dep_devices);

	return ret;

}



static acpi_status san_consumer_setup(acpi_handle handle, u32 lvl,