drivers/input/input-compat.c

   1 /*
   2  * 32bit compatibility wrappers for the input subsystem.
   3  *
   4  * Very heavily based on evdev.c - Copyright (c) 1999-2002 Vojtech Pavlik
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 as published by
   8  * the Free Software Foundation.
   9  */
  10
  11 #include <asm/uaccess.h>
  12 #include "input-compat.h"
  13
  14 #ifdef CONFIG_COMPAT
  15
  16 int input_event_from_user(const char __user *buffer,
  17                           struct input_event *event)
  18 {
  19         if (INPUT_COMPAT_TEST) {
  20                 struct input_event_compat compat_event;
  21
  22                 if (copy_from_user(&compat_event, buffer,
  23                                    sizeof(struct input_event_compat)))
  24                         return -EFAULT;
  25
  26                 event->time.tv_sec = compat_event.time.tv_sec;
  27                 event->time.tv_usec = compat_event.time.tv_usec;
  28                 event->type = compat_event.type;
  29                 event->code = compat_event.code;
  30                 event->value = compat_event.value;
  31
  32         } else {
  33                 if (copy_from_user(event, buffer, sizeof(struct input_event)))
  34                         return -EFAULT;
  35         }
  36
  37         return 0;
  38 }
  39
  40 int input_event_to_user(char __user *buffer,
  41                         const struct input_event *event)
  42 {
  43         if (INPUT_COMPAT_TEST) {
  44                 struct input_event_compat compat_event;
  45
  46                 compat_event.time.tv_sec = event->time.tv_sec;
  47                 compat_event.time.tv_usec = event->time.tv_usec;
  48                 compat_event.type = event->type;
  49                 compat_event.code = event->code;
  50                 compat_event.value = event->value;
  51
  52                 if (copy_to_user(buffer, &compat_event,
  53                                  sizeof(struct input_event_compat)))
  54                         return -EFAULT;
  55
  56         } else {
  57                 if (copy_to_user(buffer, event, sizeof(struct input_event)))
  58                         return -EFAULT;
  59         }
  60
  61         return 0;
  62 }
  63
  64 int input_ff_effect_from_user(const char __user *buffer, size_t size,
  65                               struct ff_effect *effect)
  66 {
  67         if (INPUT_COMPAT_TEST) {
  68                 struct ff_effect_compat *compat_effect;
  69
  70                 if (size != sizeof(struct ff_effect_compat))
  71                         return -EINVAL;
  72
  73                 /*
  74                  * It so happens that the pointer which needs to be changed
  75                  * is the last field in the structure, so we can retrieve the
  76                  * whole thing and replace just the pointer.
  77                  */
  78                 compat_effect = (struct ff_effect_compat *)effect;
  79
  80                 if (copy_from_user(compat_effect, buffer,
  81                                    sizeof(struct ff_effect_compat)))
  82                         return -EFAULT;
  83
  84                 if (compat_effect->type == FF_PERIODIC &&
  85                     compat_effect->u.periodic.waveform == FF_CUSTOM)
  86                         effect->u.periodic.custom_data =
  87                                 compat_ptr(compat_effect->u.periodic.custom_data);
  88         } else {
  89                 if (size != sizeof(struct ff_effect))
  90                         return -EINVAL;
  91
  92                 if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
  93                         return -EFAULT;
  94         }
  95
  96         return 0;
  97 }
  98
  99 #else
 100
 101 int input_event_from_user(const char __user *buffer,
 102                          struct input_event *event)
 103 {
 104         if (copy_from_user(event, buffer, sizeof(struct input_event)))
 105                 return -EFAULT;
 106
 107         return 0;
 108 }
 109
 110 int input_event_to_user(char __user *buffer,
 111                         const struct input_event *event)
 112 {
 113         if (copy_to_user(buffer, event, sizeof(struct input_event)))
 114                 return -EFAULT;
 115
 116         return 0;
 117 }
 118
 119 int input_ff_effect_from_user(const char __user *buffer, size_t size,
 120                               struct ff_effect *effect)
 121 {
 122         if (size != sizeof(struct ff_effect))
 123                 return -EINVAL;
 124
 125         if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
 126                 return -EFAULT;
 127
 128         return 0;
 129 }
 130
 131 #endif /* CONFIG_COMPAT */
 132
 133 EXPORT_SYMBOL_GPL(input_event_from_user);
 134 EXPORT_SYMBOL_GPL(input_event_to_user);
 135 EXPORT_SYMBOL_GPL(input_ff_effect_from_user);