From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- drivers/acpi/tiny-power-button.c | 87 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 drivers/acpi/tiny-power-button.c (limited to 'drivers/acpi/tiny-power-button.c') diff --git a/drivers/acpi/tiny-power-button.c b/drivers/acpi/tiny-power-button.c new file mode 100644 index 000000000..92516ef84 --- /dev/null +++ b/drivers/acpi/tiny-power-button.c @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Josh Triplett"); +MODULE_DESCRIPTION("ACPI Tiny Power Button Driver"); +MODULE_LICENSE("GPL"); + +static int power_signal __read_mostly = CONFIG_ACPI_TINY_POWER_BUTTON_SIGNAL; +module_param(power_signal, int, 0644); +MODULE_PARM_DESC(power_signal, "Power button sends this signal to init"); + +static const struct acpi_device_id tiny_power_button_device_ids[] = { + { ACPI_BUTTON_HID_POWER, 0 }, + { ACPI_BUTTON_HID_POWERF, 0 }, + { "", 0 }, +}; +MODULE_DEVICE_TABLE(acpi, tiny_power_button_device_ids); + +static void acpi_tiny_power_button_notify(acpi_handle handle, u32 event, void *data) +{ + kill_cad_pid(power_signal, 1); +} + +static void acpi_tiny_power_button_notify_run(void *not_used) +{ + acpi_tiny_power_button_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, NULL); +} + +static u32 acpi_tiny_power_button_event(void *not_used) +{ + acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_tiny_power_button_notify_run, NULL); + return ACPI_INTERRUPT_HANDLED; +} + +static int acpi_tiny_power_button_probe(struct platform_device *pdev) +{ + struct acpi_device *device; + acpi_status status; + + device = ACPI_COMPANION(&pdev->dev); + if (!device) + return -ENODEV; + + if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) { + status = acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON, + acpi_tiny_power_button_event, + NULL); + } else { + status = acpi_install_notify_handler(device->handle, + ACPI_DEVICE_NOTIFY, + acpi_tiny_power_button_notify, + NULL); + } + if (ACPI_FAILURE(status)) + return -ENODEV; + + return 0; +} + +static void acpi_tiny_power_button_remove(struct platform_device *pdev) +{ + struct acpi_device *device = ACPI_COMPANION(&pdev->dev); + + if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) { + acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON, + acpi_tiny_power_button_event); + } else { + acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, + acpi_tiny_power_button_notify); + } + acpi_os_wait_events_complete(); +} + +static struct platform_driver acpi_tiny_power_button_driver = { + .probe = acpi_tiny_power_button_probe, + .remove = acpi_tiny_power_button_remove, + .driver = { + .name = "acpi-tiny-power-button", + .acpi_match_table = tiny_power_button_device_ids, + }, +}; + +module_platform_driver(acpi_tiny_power_button_driver); -- cgit v1.3.1