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/drm_ioctl.h>
32
33 #include "i915_drv.h"
34 #include "i915_ioc32.h"
35
36 struct drm_i915_getparam32 {
37 s32 param;
38 /*
39 * We screwed up the generic ioctl struct here and used a variable-sized
40 * pointer. Use u32 in the compat struct to match the 32bit pointer
41 * userspace expects.
42 */
43 u32 value;
44 };
45
compat_i915_getparam(struct file * file,unsigned int cmd,unsigned long arg)46 static int compat_i915_getparam(struct file *file, unsigned int cmd,
47 unsigned long arg)
48 {
49 struct drm_i915_getparam32 req32;
50 struct drm_i915_getparam req;
51
52 if (copy_from_user(&req32, (void __user *)arg, sizeof(req32)))
53 return -EFAULT;
54
55 req.param = req32.param;
56 req.value = compat_ptr(req32.value);
57
58 return drm_ioctl_kernel(file, i915_getparam_ioctl, &req,
59 DRM_RENDER_ALLOW);
60 }
61
62 static drm_ioctl_compat_t *i915_compat_ioctls[] = {
63 [DRM_I915_GETPARAM] = compat_i915_getparam,
64 };
65
66 /**
67 * i915_ioc32_compat_ioctl - handle the mistakes of the past
68 * @filp: the file pointer
69 * @cmd: the ioctl command (and encoded flags)
70 * @arg: the ioctl argument (from userspace)
71 *
72 * Called whenever a 32-bit process running under a 64-bit kernel
73 * performs an ioctl on /dev/dri/card<n>.
74 */
i915_ioc32_compat_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)75 long i915_ioc32_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
76 {
77 unsigned int nr = DRM_IOCTL_NR(cmd);
78 drm_ioctl_compat_t *fn = NULL;
79 int ret;
80
81 if (nr < DRM_COMMAND_BASE || nr >= DRM_COMMAND_END)
82 return drm_compat_ioctl(filp, cmd, arg);
83
84 if (nr < DRM_COMMAND_BASE + ARRAY_SIZE(i915_compat_ioctls))
85 fn = i915_compat_ioctls[nr - DRM_COMMAND_BASE];
86
87 if (fn != NULL)
88 ret = (*fn) (filp, cmd, arg);
89 else
90 ret = drm_ioctl(filp, cmd, arg);
91
92 return ret;
93 }
94