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 <xen/acpi.h>
  29
  30 #ifdef CONFIG_ACPI
  31
  32 /*--------------------------------------------
  33         stub driver for Xen memory hotplug
  34 --------------------------------------------*/
  35
  36 static const struct acpi_device_id memory_device_ids[] = {
  37         {ACPI_MEMORY_DEVICE_HID, 0},
  38         {"", 0},
  39 };
  40
  41 static struct acpi_driver xen_stub_memory_device_driver = {
  42         /* same name as native memory driver to block native loaded */
  43         .name = "acpi_memhotplug",
  44         .class = ACPI_MEMORY_DEVICE_CLASS,
  45         .ids = memory_device_ids,
  46 };
  47
  48 int xen_stub_memory_device_init(void)
  49 {
  50         if (!xen_initial_domain())
  51                 return -ENODEV;
  52
  53         /* just reserve space for Xen, block native driver loaded */
  54         return acpi_bus_register_driver(&xen_stub_memory_device_driver);
  55 }
  56 EXPORT_SYMBOL_GPL(xen_stub_memory_device_init);
  57 subsys_initcall(xen_stub_memory_device_init);
  58
  59 void xen_stub_memory_device_exit(void)
  60 {
  61         acpi_bus_unregister_driver(&xen_stub_memory_device_driver);
  62 }
  63 EXPORT_SYMBOL_GPL(xen_stub_memory_device_exit);
  64
  65
  66 /*--------------------------------------------
  67         stub driver for Xen cpu hotplug
  68 --------------------------------------------*/
  69
  70 static const struct acpi_device_id processor_device_ids[] = {
  71         {ACPI_PROCESSOR_OBJECT_HID, 0},
  72         {ACPI_PROCESSOR_DEVICE_HID, 0},
  73         {"", 0},
  74 };
  75
  76 static struct acpi_driver xen_stub_processor_driver = {
  77         /* same name as native processor driver to block native loaded */
  78         .name = "processor",
  79         .class = ACPI_PROCESSOR_CLASS,
  80         .ids = processor_device_ids,
  81 };
  82
  83 int xen_stub_processor_init(void)
  84 {
  85         if (!xen_initial_domain())
  86                 return -ENODEV;
  87
  88         /* just reserve space for Xen, block native driver loaded */
  89         return acpi_bus_register_driver(&xen_stub_processor_driver);
  90 }
  91 EXPORT_SYMBOL_GPL(xen_stub_processor_init);
  92 subsys_initcall(xen_stub_processor_init);
  93
  94 void xen_stub_processor_exit(void)
  95 {
  96         acpi_bus_unregister_driver(&xen_stub_processor_driver);
  97 }
  98 EXPORT_SYMBOL_GPL(xen_stub_processor_exit);
  99
 100 #endif