/* SPDX-License-Identifier: GPL-2.0 */
/*
* Authors: Bjorn Wesen (bjornw@axis.com)
* Hans-Peter Nilsson (hp@axis.com)
*/
/* Asm:s have been tweaked (within the domain of correctness) to give
satisfactory results for "gcc version 2.96 20000427 (experimental)".
Check regularly...
Register $r9 is chosen for temporaries, being a call-clobbered register
first in line to be used (notably for local blocks), not colliding with
parameter registers. */
#ifndef _CRIS_UACCESS_H
#define _CRIS_UACCESS_H
#include <asm/processor.h>
#include <asm/page.h>
/*
* The fs value determines whether argument validity checking should be
* performed or not. If get_fs() == USER_DS, checking is performed, with
* get_fs() == KERNEL_DS, checking is bypassed.
*
* For historical reasons, these macros are grossly misnamed.
*/
#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
/* addr_limit is the maximum accessible address for the task. we misuse
* the KERNEL_DS and USER_DS values to both assign and compare the
* addr_limit values through the equally misnamed get/set_fs macros.
* (see above)
*/
#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF)
#define USER_DS MAKE_MM_SEG(TASK_SIZE)
#define get_ds() (KERNEL_DS)
#define get_fs() (current_thread_info()->addr_limit)
#define set_fs(x) (current_thread_info()->addr_limit = (x))
#define segment_eq(a, b) ((a).seg == (b).seg)
#define __kernel_ok (uaccess_kernel())
#define __user_ok(addr, size) \
(((size) <= TASK_SIZE) && ((addr) <= TASK_SIZE-(size)))
#define __access_ok(addr, size) (__kernel_ok || __user_ok((addr), (size)))
#define access_ok(type, addr, size) __access_ok((unsigned long)(addr), (size))
#include <arch/uaccess.h>
#include <asm/extable.h>
/*
* These are the main single-value transfer routines. They automatically
* use the right size if we just have the right pointer type.
*
* This gets kind of ugly. We want to return _two_ values in "get_user()"
* and yet we don't want to do any pointers, because that is too much
* of a performance impact. Thus we have a few rather ugly macros here,
* and hide all the ugliness from the user.
*
* The "__xxx" versions of the user access functions are versions that
* do not verify the address space, that must have been done previously
* with a separate "access_ok()" call (this is used when we do multiple
* accesses to the same area of user memory).
*
* As we use the same address space for kernel and user data on
* CRIS, we can just do these as direct assignments. (Of course, the
* exception handling means that it's no longer "just"...)
*/
#define get_user(x, ptr) \
__get_user_check((x), (ptr), sizeof(*(ptr)))
#define put_user(x, ptr) \
__put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
#define __get_user(x, ptr) \
__get_user_nocheck((x), (ptr), sizeof(*(ptr)))
#define __put_user(x, ptr) \
__put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
extern long __put_user_bad(void);
#define __put_user_size(x, ptr, size, retval) \
do { \
retval = 0; \
switch (size) { \
case 1: \
__put_user_asm(x, ptr, retval, "move.b"); \
break; \
case 2: \
__put_user_asm(x, ptr, retval, "move.w"); \
break; \
case 4: \
__put_user_asm(x, ptr, retval, "move.d"); \
break; \
case 8: \
__put_user_asm_64(x, ptr, retval); \
break; \
default: \
__put_user_bad(); \
} \
} while (0)
#define __get_user_size(x, ptr, size, retval) \
do { \
retval = 0; \
switch (size) { \
case 1: \
__get_user_asm(x, ptr, retval, "move.b"); \
break; \
case 2: \
__get_user_asm(x, ptr, retval, "move.w"); \
break; \
case 4: \
__get_user_asm(x, ptr, retval, "move.d"); \
break; \
case 8: \
__get_user_asm_64(x, ptr, retval); \
break; \
default: \
(x) = __get_user_bad(); \
} \
} while (0)
#define __put_user_nocheck(x, ptr, size) \
({ \
long __pu_err; \
__put_user_size((x), (ptr), (size), __pu_err); \
__pu_err; \
})
#define __put_user_check(x, ptr, size) \
({ \
long __pu_err = -EFAULT; \
__typeof__(*(ptr)) *__pu_addr = (ptr); \
if (access_ok(VERIFY_WRITE, __pu_addr, size)) \
__put_user_size((x), __pu_addr, (size), __pu_err); \
__pu_err; \
})
struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct *)(x))
#define __get_user_nocheck(x, ptr, size) \
({ \
long __gu_err, __gu_val; \
__get_user_size(__gu_val, (ptr), (size), __gu_err); \
(x) = (__force __typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
#define __get_user_check(x, ptr, size) \
({ \
long __gu_err = -EFAULT, __gu_val = 0; \
const __typeof__(*(ptr)) *__gu_addr = (ptr); \
if (access_ok(VERIFY_READ, __gu_addr, size)) \
__get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
(x) = (__force __typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
extern long __get_user_bad(void);
/* More complex functions. Most are inline, but some call functions that
live in lib/usercopy.c */
extern unsigned long __copy_user(void __user *to, const void *from, unsigned long n);
extern unsigned long __copy_user_in(void *to, const void __user *from, unsigned long n);
extern unsigned long __do_clear_user(void __user *to, unsigned long n);
static inline long
strncpy_from_user(char *dst, const char __user *src, long count)
{
long res = -EFAULT;
if (access_ok(VERIFY_READ, src, 1))
res = __do_strncpy_from_user(dst, src, count);
return res;
}
/* Note that these expand awfully if made into switch constructs, so
don't do that. */
static inline unsigned long
__constant_copy_from_user(void *to, const void __user *from, unsigned long n)
{
unsigned long ret = 0;
if (n == 0)
;
else if (n == 1)
__asm_copy_from_user_1(to, from, ret);
else if (n == 2)
__asm_copy_from_user_2(to, from, ret);
else if (n == 3)
__asm_copy_from_user_3(to, from, ret);
else if (n == 4)
__asm_copy_from_user_4(to, from, ret);
else if (n == 5)
__asm_copy_from_user_5(to, from, ret);
else if (n == 6)
__asm_copy_from_user_6(to, from, ret);
else if (n == 7)
__asm_copy_from_user_7(to, from, ret);
else if (n == 8)
__asm_copy_from_user_8(to, from, ret);
else if (n == 9)
__asm_copy_from_user_9(to, from, ret);
else if (n == 10)
__asm_copy_from_user_10(to, from, ret);
else if (n == 11)
__asm_copy_from_user_11(to, from, ret);
else if (n == 12)
__asm_copy_from_user_12(to, from, ret);
else if (n == 13)
__asm_copy_from_user_13(to, from, ret);
else if (n == 14)
__asm_copy_from_user_14(to, from, ret);
else if (n == 15)
__asm_copy_from_user_15(to, from, ret);
else if (n == 16)
__asm_copy_from_user_16(to, from, ret);
else if (n == 20)
__asm_copy_from_user_20(to, from, ret);
else if (n == 24)
__asm_copy_from_user_24(to, from, ret);
else
ret = __copy_user_in(to, from, n);
return ret;
}
/* Ditto, don't make a switch out of this. */
static inline unsigned long
__constant_copy_to_user(void __user *to, const void *from, unsigned long n)
{
unsigned long ret = 0;
if (n == 0)
;
else if (n == 1)
__asm_copy_to_user_1(to, from, ret);
else if (n == 2)
__asm_copy_to_user_2(to, from, ret);
else if (n == 3)
__asm_copy_to_user_3(to, from, ret);
else if (n == 4)
__asm_copy_to_user_4(to, from, ret);
else if (n == 5)
__asm_copy_to_user_5(to, from, ret);
else if (n == 6)
__asm_copy_to_user_6(to, from, ret);
else if (n == 7)
__asm_copy_to_user_7(to, from, ret);
else if (n == 8)
__asm_copy_to_user_8(to, from, ret);
else if (n == 9)
__asm_copy_to_user_9(to, from, ret);
else if (n == 10)
__asm_copy_to_user_10(to, from, ret);
else if (n == 11)
__asm_copy_to_user_11(to, from, ret);
else if (n == 12)
__asm_copy_to_user_12(to, from, ret);
else if (n == 13)
__asm_copy_to_user_13(to, from, ret);
else if (n == 14)
__asm_copy_to_user_14(to, from, ret);
else if (n == 15)
__asm_copy_to_user_15(to, from, ret);
else if (n == 16)
__asm_copy_to_user_16(to, from, ret);
else if (n == 20)
__asm_copy_to_user_20(to, from, ret);
else if (n == 24)
__asm_copy_to_user_24(to, from, ret);
else
ret = __copy_user(to, from, n);
return ret;
}
/* No switch, please. */
static inline unsigned long
__constant_clear_user(void __user *to, unsigned long n)
{
unsigned long ret = 0;
if (n == 0)
;
else if (n == 1)
__asm_clear_1(to, ret);
else if (n == 2)
__asm_clear_2(to, ret);
else if (n == 3)
__asm_clear_3(to, ret);
else if (n == 4)
__asm_clear_4(to, ret);
else if (n == 8)
__asm_clear_8(to, ret);
else if (n == 12)
__asm_clear_12(to, ret);
else if (n == 16)
__asm_clear_16(to, ret);
else if (n == 20)
__asm_clear_20(to, ret);
else if (n == 24)
__asm_clear_24(to, ret);
else
ret = __do_clear_user(to, n);
return ret;
}
static inline size_t clear_user(void __user *to, size_t n)
{
if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
return n;
if (__builtin_constant_p(n))
return __constant_clear_user(to, n);
else
return __do_clear_user(to, n);
}
static inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
if (__builtin_constant_p(n))
return __constant_copy_from_user(to, from, n);
else
return __copy_user_in(to, from, n);
}
static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
if (__builtin_constant_p(n))
return __constant_copy_to_user(to, from, n);
else
return __copy_user(to, from, n);
}
#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER
static inline unsigned long
__clear_user(void __user *to, unsigned long n)
{
return __do_clear_user(to, n);
}
#endif /* _CRIS_UACCESS_H */