drivers/xen/xen-stub.c

   1 /*
   2  * xen-stub.c - stub drivers to reserve space for Xen
   3  *
   4  * Copyright (C) 2012 Intel Corporation
   5  *    Author: Liu Jinsong <jinsong.liu@intel.com>
   6  *    Author: Jiang Yunhong <yunhong.jiang@intel.com>
   7  *
   8  * Copyright (C) 2012 Oracle Inc
   9  *    Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or (at
  14  * your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  19  * NON INFRINGEMENT.  See the GNU General Public License for more
  20  * details.
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/init.h>
  25 #include <linux/export.h>
  26 #include <linux/types.h>
  27 #include <linux/acpi.h>
  28 #include <acpi/acpi_drivers.h>
  29 #include <xen/acpi.h>
  30
  31 #ifdef CONFIG_ACPI
  32
  33 /*--------------------------------------------
  34         stub driver for Xen memory hotplug
  35 --------------------------------------------*/
  36
  37 static const struct acpi_device_id memory_device_ids[] = {
  38         {ACPI_MEMORY_DEVICE_HID, 0},
  39         {"", 0},
  40 };
  41
  42 static struct acpi_driver xen_stub_memory_device_driver = {
  43         /* same name as native memory driver to block native loaded */
  44         .name = "acpi_memhotplug",
  45         .class = ACPI_MEMORY_DEVICE_CLASS,
  46         .ids = memory_device_ids,
  47 };
  48
  49 int xen_stub_memory_device_init(void)
  50 {
  51         if (!xen_initial_domain())
  52                 return -ENODEV;
  53
  54         /* just reserve space for Xen, block native driver loaded */
  55         return acpi_bus_register_driver(&xen_stub_memory_device_driver);
  56 }
  57 EXPORT_SYMBOL_GPL(xen_stub_memory_device_init);
  58 subsys_initcall(xen_stub_memory_device_init);
  59
  60 void xen_stub_memory_device_exit(void)
  61 {
  62         acpi_bus_unregister_driver(&xen_stub_memory_device_driver);
  63 }
  64 EXPORT_SYMBOL_GPL(xen_stub_memory_device_exit);
  65
  66
  67 /*--------------------------------------------
  68         stub driver for Xen cpu hotplug
  69 --------------------------------------------*/
  70
  71 static const struct acpi_device_id processor_device_ids[] = {
  72         {ACPI_PROCESSOR_OBJECT_HID, 0},
  73         {ACPI_PROCESSOR_DEVICE_HID, 0},
  74         {"", 0},
  75 };
  76
  77 static struct acpi_driver xen_stub_processor_driver = {
  78         /* same name as native processor driver to block native loaded */
  79         .name = "processor",
  80         .class = ACPI_PROCESSOR_CLASS,
  81         .ids = processor_device_ids,
  82 };
  83
  84 int xen_stub_processor_init(void)
  85 {
  86         if (!xen_initial_domain())
  87                 return -ENODEV;
  88
  89         /* just reserve space for Xen, block native driver loaded */
  90         return acpi_bus_register_driver(&xen_stub_processor_driver);
  91 }
  92 EXPORT_SYMBOL_GPL(xen_stub_processor_init);
  93 subsys_initcall(xen_stub_processor_init);
  94
  95 void xen_stub_processor_exit(void)
  96 {
  97         acpi_bus_unregister_driver(&xen_stub_processor_driver);
  98 }
  99 EXPORT_SYMBOL_GPL(xen_stub_processor_exit);
 100
 101 #endif