linux/arch/c6x/include/asm/uaccess.h

108 lines
2.3 KiB
C

/*
* Copyright (C) 2011 Texas Instruments Incorporated
* Author: Mark Salter <msalter@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _ASM_C6X_UACCESS_H
#define _ASM_C6X_UACCESS_H
#include <linux/types.h>
#include <linux/compiler.h>
#include <linux/string.h>
#ifdef CONFIG_ACCESS_CHECK
#define __access_ok _access_ok
#endif
/*
* __copy_from_user/copy_to_user are based on ones in asm-generic/uaccess.h
*
* C6X supports unaligned 32 and 64 bit loads and stores.
*/
static inline __must_check long __copy_from_user(void *to,
const void __user *from, unsigned long n)
{
u32 tmp32;
u64 tmp64;
if (__builtin_constant_p(n)) {
switch (n) {
case 1:
*(u8 *)to = *(u8 __force *)from;
return 0;
case 4:
asm volatile ("ldnw .d1t1 *%2,%0\n"
"nop 4\n"
"stnw .d1t1 %0,*%1\n"
: "=&a"(tmp32)
: "A"(to), "a"(from)
: "memory");
return 0;
case 8:
asm volatile ("ldndw .d1t1 *%2,%0\n"
"nop 4\n"
"stndw .d1t1 %0,*%1\n"
: "=&a"(tmp64)
: "a"(to), "a"(from)
: "memory");
return 0;
default:
break;
}
}
memcpy(to, (const void __force *)from, n);
return 0;
}
static inline __must_check long __copy_to_user(void __user *to,
const void *from, unsigned long n)
{
u32 tmp32;
u64 tmp64;
if (__builtin_constant_p(n)) {
switch (n) {
case 1:
*(u8 __force *)to = *(u8 *)from;
return 0;
case 4:
asm volatile ("ldnw .d1t1 *%2,%0\n"
"nop 4\n"
"stnw .d1t1 %0,*%1\n"
: "=&a"(tmp32)
: "a"(to), "a"(from)
: "memory");
return 0;
case 8:
asm volatile ("ldndw .d1t1 *%2,%0\n"
"nop 4\n"
"stndw .d1t1 %0,*%1\n"
: "=&a"(tmp64)
: "a"(to), "a"(from)
: "memory");
return 0;
default:
break;
}
}
memcpy((void __force *)to, from, n);
return 0;
}
#define __copy_to_user __copy_to_user
#define __copy_from_user __copy_from_user
extern int _access_ok(unsigned long addr, unsigned long size);
#ifdef CONFIG_ACCESS_CHECK
#define __access_ok _access_ok
#endif
#include <asm-generic/uaccess.h>
#endif /* _ASM_C6X_UACCESS_H */