===================================================================
@@ -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 hand
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 *
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 *
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 *
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
===================================================================
@@ -298,6 +298,7 @@ struct acpi_device {
struct list_head children;
struct list_head node;
struct list_head wakeup_list;
+ struct list_head del_list;
struct acpi_device_status status;
struct acpi_device_flags flags;
struct acpi_device_pnp pnp;
===================================================================
@@ -1215,6 +1215,10 @@ acpi_status acpi_hotplug_execute(acpi_hp
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(v
{
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);
===================================================================
@@ -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
-------------------------------------------------------------------------- */