freebsd-nq/sys/compat/linuxkpi/common/include/linux/uaccess.h
Hans Petter Selasky 3a8bec33ef Fix handling of IOCTLs in the LinuxKPI.
Linux requires that all IOCTL data resides in userspace. FreeBSD
always moves the main IOCTL structure into a kernel buffer before
invoking the IOCTL handler and then copies it back into userspace,
before returning. Hide this difference in the "linux_copyin()" and
"linux_copyout()" functions by remapping userspace addresses in the
range from 0x10000 to 0x20000, to the kernel IOCTL data buffer.

It is assumed that the userspace code, data and stack segments starts
no lower than memory address 0x400000, which is also stated by "man 1
ld", which means any valid userspace pointer can be passed to regular
LinuxKPI handled IOCTLs.

Bump the FreeBSD version to force recompilation of all kernel modules.

Discussed with:	kmacy @
MFC after:	1 week
Sponsored by:	Mellanox Technologies
2016-05-12 11:38:28 +00:00

73 lines
2.5 KiB
C

/*-
* Copyright (c) 2010 Isilon Systems, Inc.
* Copyright (c) 2010 iX Systems, Inc.
* Copyright (c) 2010 Panasas, Inc.
* Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
* Copyright (c) 2015 François Tigeot
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _LINUX_UACCESS_H_
#define _LINUX_UACCESS_H_
#include <linux/compiler.h>
#define __get_user(_x, _p) ({ \
int __err; \
__typeof(*(_p)) __x; \
__err = linux_copyin((_p), &(__x), sizeof(*(_p))); \
(_x) = __x; \
__err; \
})
#define __put_user(_x, _p) ({ \
__typeof(*(_p)) __x = (_x); \
linux_copyout(&(__x), (_p), sizeof(*(_p))); \
})
#define get_user(_x, _p) linux_copyin((_p), &(_x), sizeof(*(_p)))
#define put_user(_x, _p) linux_copyout(&(_x), (_p), sizeof(*(_p)))
extern int linux_copyin(const void *uaddr, void *kaddr, size_t len);
extern int linux_copyout(const void *kaddr, void *uaddr, size_t len);
/*
* NOTE: The returned value from pagefault_disable() must be stored
* and passed to pagefault_enable(). Else possible recursion on the
* state can be lost.
*/
static inline int __must_check
pagefault_disable(void)
{
return (vm_fault_disable_pagefaults());
}
static inline void
pagefault_enable(int save)
{
vm_fault_enable_pagefaults(save);
}
#endif /* _LINUX_UACCESS_H_ */