linux/drivers/gpu/drm/i915/i915_ioc32.c
Al Viro fd7cd8da23 i915 compat ioctl(): just use drm_ioctl_kernel()
compat_alloc_user_space() is a bad kludge; the sooner it goes, the
better...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-01 20:35:26 -04:00

94 lines
2.9 KiB
C

/*
* 32-bit ioctl compatibility routines for the i915 DRM.
*
* Copyright (C) Paul Mackerras 2005
* Copyright (C) Alan Hourihane 2005
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* Author: Alan Hourihane <alanh@fairlite.demon.co.uk>
*/
#include <linux/compat.h>
#include <drm/drm_ioctl.h>
#include "i915_drv.h"
#include "i915_ioc32.h"
struct drm_i915_getparam32 {
s32 param;
/*
* We screwed up the generic ioctl struct here and used a variable-sized
* pointer. Use u32 in the compat struct to match the 32bit pointer
* userspace expects.
*/
u32 value;
};
static int compat_i915_getparam(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct drm_i915_getparam32 req32;
struct drm_i915_getparam req;
if (copy_from_user(&req32, (void __user *)arg, sizeof(req32)))
return -EFAULT;
req.param = req32.param;
req.value = compat_ptr(req32.value);
return drm_ioctl_kernel(file, i915_getparam_ioctl, &req,
DRM_RENDER_ALLOW);
}
static drm_ioctl_compat_t *i915_compat_ioctls[] = {
[DRM_I915_GETPARAM] = compat_i915_getparam,
};
/**
* i915_ioc32_compat_ioctl - handle the mistakes of the past
* @filp: the file pointer
* @cmd: the ioctl command (and encoded flags)
* @arg: the ioctl argument (from userspace)
*
* Called whenever a 32-bit process running under a 64-bit kernel
* performs an ioctl on /dev/dri/card<n>.
*/
long i915_ioc32_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
unsigned int nr = DRM_IOCTL_NR(cmd);
drm_ioctl_compat_t *fn = NULL;
int ret;
if (nr < DRM_COMMAND_BASE || nr >= DRM_COMMAND_END)
return drm_compat_ioctl(filp, cmd, arg);
if (nr < DRM_COMMAND_BASE + ARRAY_SIZE(i915_compat_ioctls))
fn = i915_compat_ioctls[nr - DRM_COMMAND_BASE];
if (fn != NULL)
ret = (*fn) (filp, cmd, arg);
else
ret = drm_ioctl(filp, cmd, arg);
return ret;
}