diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/internal.h | 2 | ||||
| -rw-r--r-- | drivers/acpi/osl.c | 6 | ||||
| -rw-r--r-- | drivers/acpi/scan.c | 114 |
3 files changed, 101 insertions, 21 deletions
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index a29739c0ba79..d8606498bf6f 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -73,6 +73,8 @@ void acpi_lpss_init(void); static inline void acpi_lpss_init(void) {} #endif +bool acpi_queue_hotplug_work(struct work_struct *work); + /* -------------------------------------------------------------------------- Device Node Initialization / Removal -------------------------------------------------------------------------- */ diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 54a20ff4b864..5b9a785e2155 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -1215,6 +1215,10 @@ acpi_status acpi_hotplug_execute(acpi_hp_callback func, void *data, u32 src) return AE_OK; } +bool acpi_queue_hotplug_work(struct work_struct *work) +{ + return queue_work(kacpi_hotplug_wq, work); +} acpi_status acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle * handle) @@ -1794,7 +1798,7 @@ acpi_status __init acpi_os_initialize1(void) { kacpid_wq = alloc_workqueue("kacpid", 0, 1); kacpi_notify_wq = alloc_workqueue("kacpi_notify", 0, 1); - kacpi_hotplug_wq = alloc_workqueue("kacpi_hotplug", 0, 1); + kacpi_hotplug_wq = alloc_ordered_workqueue("kacpi_hotplug", 0); BUG_ON(!kacpid_wq); BUG_ON(!kacpi_notify_wq); BUG_ON(!kacpi_hotplug_wq); diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index fd39459926b1..ad2522015e5e 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -14,6 +14,8 @@ #include <acpi/acpi_drivers.h> +#include <asm/pgtable.h> + #include "internal.h" #define _COMPONENT ACPI_BUS_COMPONENT @@ -27,6 +29,8 @@ extern struct acpi_device *acpi_root; #define ACPI_IS_ROOT_DEVICE(device) (!(device)->parent) +#define INVALID_ACPI_HANDLE ((acpi_handle)empty_zero_page) + /* * If set, devices will be hot-removed even if they cannot be put offline * gracefully (from the kernel's standpoint). @@ -907,9 +911,91 @@ struct bus_type acpi_bus_type = { .uevent = acpi_device_uevent, }; -static void acpi_bus_data_handler(acpi_handle handle, void *context) +static void acpi_device_del(struct acpi_device *device) +{ + mutex_lock(&acpi_device_lock); + if (device->parent) + list_del(&device->node); + + list_del(&device->wakeup_list); + mutex_unlock(&acpi_device_lock); + + acpi_power_add_remove_device(device, false); + acpi_device_remove_files(device); + if (device->remove) + device->remove(device); + + device_del(&device->dev); +} + +static LIST_HEAD(acpi_device_del_list); +static DEFINE_MUTEX(acpi_device_del_lock); + +static void acpi_device_del_work_fn(struct work_struct *work_not_used) +{ + for (;;) { + struct acpi_device *adev; + + mutex_lock(&acpi_device_del_lock); + + if (list_empty(&acpi_device_del_list)) { + mutex_unlock(&acpi_device_del_lock); + break; + } + adev = list_first_entry(&acpi_device_del_list, + struct acpi_device, del_list); + list_del(&adev->del_list); + + mutex_unlock(&acpi_device_del_lock); + + acpi_device_del(adev); + /* + * Drop references to all power resources that might have been + * used by the device. + */ + acpi_power_transition(adev, ACPI_STATE_D3_COLD); + put_device(&adev->dev); + } +} + +/** + * acpi_scan_drop_device - Drop an ACPI device object. + * @handle: Handle of an ACPI namespace node, not used. + * @context: Address of the ACPI device object to drop. + * + * This is invoked by acpi_ns_delete_node() during the removal of the ACPI + * namespace node the device object pointed to by @context is attached to. + * + * The unregistration is carried out asynchronously to avoid running + * acpi_device_del() under the ACPICA's namespace mutex and the list is used to + * ensure the correct ordering (the device objects must be unregistered in the + * same order in which the corresponding namespace nodes are deleted). + */ +static void acpi_scan_drop_device(acpi_handle handle, void *context) { - /* Intentionally empty. */ + static DECLARE_WORK(work, acpi_device_del_work_fn); + struct acpi_device *adev = context; + + mutex_lock(&acpi_device_del_lock); + + /* + * Use the ACPI hotplug workqueue which is ordered, so this work item + * won't run after any hotplug work items submitted subsequently. That + * prevents attempts to register device objects identical to those being + * deleted from happening concurrently (such attempts result from + * hotplug events handled via the ACPI hotplug workqueue). It also will + * run after all of the work items submitted previosuly, which helps + * those work items to ensure that they are not accessing stale device + * objects. + */ + if (list_empty(&acpi_device_del_list)) + acpi_queue_hotplug_work(&work); + + list_add_tail(&adev->del_list, &acpi_device_del_list); + /* Make acpi_ns_validate_handle() return NULL for this handle. */ + adev->handle = INVALID_ACPI_HANDLE; + + mutex_unlock(&acpi_device_del_lock); } int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device) @@ -919,7 +1005,7 @@ int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device) if (!device) return -EINVAL; - status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device); + status = acpi_get_data(handle, acpi_scan_drop_device, (void **)device); if (ACPI_FAILURE(status) || !*device) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n", handle)); @@ -939,7 +1025,7 @@ int acpi_device_add(struct acpi_device *device, if (device->handle) { acpi_status status; - status = acpi_attach_data(device->handle, acpi_bus_data_handler, + status = acpi_attach_data(device->handle, acpi_scan_drop_device, device); if (ACPI_FAILURE(status)) { acpi_handle_err(device->handle, @@ -957,6 +1043,7 @@ int acpi_device_add(struct acpi_device *device, INIT_LIST_HEAD(&device->node); INIT_LIST_HEAD(&device->wakeup_list); INIT_LIST_HEAD(&device->physical_node_list); + INIT_LIST_HEAD(&device->del_list); mutex_init(&device->physical_node_lock); new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL); @@ -1020,27 +1107,14 @@ int acpi_device_add(struct acpi_device *device, mutex_unlock(&acpi_device_lock); err_detach: - acpi_detach_data(device->handle, acpi_bus_data_handler); + acpi_detach_data(device->handle, acpi_scan_drop_device); return result; } static void acpi_device_unregister(struct acpi_device *device) { - mutex_lock(&acpi_device_lock); - if (device->parent) - list_del(&device->node); - - list_del(&device->wakeup_list); - mutex_unlock(&acpi_device_lock); - - acpi_detach_data(device->handle, acpi_bus_data_handler); - - acpi_power_add_remove_device(device, false); - acpi_device_remove_files(device); - if (device->remove) - device->remove(device); - - device_del(&device->dev); + acpi_detach_data(device->handle, acpi_scan_drop_device); + acpi_device_del(device); /* * Transition the device to D3cold to drop the reference counts of all * power resources the device depends on and turn off the ones that have |
