ACPI: Add ACPI CPU hot-remove support

Added support of CPU hot-remove via an ACPI eject notification.
It calls acpi_bus_hot_remove_device(), which shares the same code
path with the sysfs eject operation.  acpi_os_hotplug_execute()
runs the hot-remove operation in kacpi_hotplug_wq and serializes
it between ACPI hot-remove and sysfs eject requests.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Tested-by: IgorMammedov <imammedo@redhat.com>
Tested-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 17 insertions, 10 deletions

diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index a4352b88a331..8cc33d0e5d8f 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -695,8 +695,8 @@ int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
 static void acpi_processor_hotplug_notify(acpi_handle handle,
                                           u32 event, void *data)
 {
-        struct acpi_processor *pr;
         struct acpi_device *device = NULL;
+        struct acpi_eject_event *ej_event = NULL;
         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
         int result;
 
@@ -728,20 +728,27 @@ static void acpi_processor_hotplug_notify(acpi_handle handle,
                                   "received ACPI_NOTIFY_EJECT_REQUEST\n"));
 
                 if (acpi_bus_get_device(handle, &device)) {
-                        printk(KERN_ERR PREFIX
-                                    "Device don't exist, dropping EJECT\n");
+                        pr_err(PREFIX "Device don't exist, dropping EJECT\n");
                         break;
                 }
-                pr = acpi_driver_data(device);
-                if (!pr) {
-                        printk(KERN_ERR PREFIX
-                                    "Driver data is NULL, dropping EJECT\n");
+                if (!acpi_driver_data(device)) {
+                        pr_err(PREFIX "Driver data is NULL, dropping EJECT\n");
                         break;
                 }
 
-                /* REVISIT: update when eject is supported */
-                ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
-                break;
+                ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
+                if (!ej_event) {
+                        pr_err(PREFIX "No memory, dropping EJECT\n");
+                        break;
+                }
+
+                ej_event->handle = handle;
+                ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
+                acpi_os_hotplug_execute(acpi_bus_hot_remove_device,
+                                        (void *)ej_event);
+
+                /* eject is performed asynchronously */
+                return;
 
         default:
                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,