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/drmP.h> 32 #include <drm/i915_drm.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 } 97