1 /*
2 * 32-bit ioctl compatibility routines for the i915 DRM.
3 *
4 * Copyright (C) Paul Mackerras 2005
5 * Copyright (C) Alan Hourihane 2005
6 * All Rights Reserved.
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a
9 * copy of this software and associated documentation files (the "Software"),
10 * to deal in the Software without restriction, including without limitation
11 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
12 * and/or sell copies of the Software, and to permit persons to whom the
13 * Software is furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the next
16 * paragraph) shall be included in all copies or substantial portions of the
17 * Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22 * THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
23 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
25 * IN THE SOFTWARE.
26 *
27 * Author: Alan Hourihane <alanh@fairlite.demon.co.uk>
28 */
29 #include <linux/compat.h>
30
31 #include <drm/i915_drm.h>
32 #include <drm/drm_ioctl.h>
33 #include "i915_drv.h"
34
35 struct drm_i915_getparam32 {
36 s32 param;
37 /*
38 * We screwed up the generic ioctl struct here and used a variable-sized
39 * pointer. Use u32 in the compat struct to match the 32bit pointer
40 * userspace expects.
41 */
42 u32 value;
43 };
44
45 static int compat_i915_getparam(struct file *file, unsigned int cmd,
46 unsigned long arg)
47 {
48 struct drm_i915_getparam32 req32;
49 drm_i915_getparam_t __user *request;
50
51 if (copy_from_user(&req32, (void __user *)arg, sizeof(req32)))
52 return -EFAULT;
53
54 request = compat_alloc_user_space(sizeof(*request));
55 if (!access_ok(request, sizeof(*request)) ||
56 __put_user(req32.param, &request->param) ||
57 __put_user((void __user *)(unsigned long)req32.value,
58 &request->value))
59 return -EFAULT;
60
61 return drm_ioctl(file, DRM_IOCTL_I915_GETPARAM,
62 (unsigned long)request);
63 }
64
65 static drm_ioctl_compat_t *i915_compat_ioctls[] = {
66 [DRM_I915_GETPARAM] = compat_i915_getparam,
67 };
68
69 /**
70 * i915_compat_ioctl - handle the mistakes of the past
71 * @filp: the file pointer
72 * @cmd: the ioctl command (and encoded flags)
73 * @arg: the ioctl argument (from userspace)
74 *
75 * Called whenever a 32-bit process running under a 64-bit kernel
76 * performs an ioctl on /dev/dri/card<n>.
77 */
78 long i915_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
79 {
80 unsigned int nr = DRM_IOCTL_NR(cmd);
81 drm_ioctl_compat_t *fn = NULL;
82 int ret;
83
84 if (nr < DRM_COMMAND_BASE || nr >= DRM_COMMAND_END)
85 return drm_compat_ioctl(filp, cmd, arg);
86
87 if (nr < DRM_COMMAND_BASE + ARRAY_SIZE(i915_compat_ioctls))
88 fn = i915_compat_ioctls[nr - DRM_COMMAND_BASE];
89
90 if (fn != NULL)
91 ret = (*fn) (filp, cmd, arg);
92 else
93 ret = drm_ioctl(filp, cmd, arg);
94
95 return ret;
96 }