u-boot/include/asm-blackfin/uaccess.h

205 lines
5.5 KiB
C

/*
* U-boot - uaccess.h
*
* Copyright (c) 2005 blackfin.uclinux.org
*
* This file is based on
* Based on: include/asm-m68knommu/uaccess.h
* Changes made by Lineo Inc. May 2001
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#ifndef __BLACKFIN_UACCESS_H
#define __BLACKFIN_UACCESS_H
/*
* User space memory access functions
*/
#include <asm/segment.h>
#include <asm/errno.h>
#define VERIFY_READ 0
#define VERIFY_WRITE 1
/* We let the MMU do all checking */
static inline int access_ok(int type, const void *addr, unsigned long size)
{
return ((unsigned long)addr < 0x10f00000); /* need final decision - Tony */
}
static inline int verify_area(int type, const void *addr, unsigned long size)
{
return access_ok(type, addr, size) ? 0 : -EFAULT;
}
/*
* The exception table consists of pairs of addresses: the first is the
* address of an instruction that is allowed to fault, and the second is
* the address at which the program should continue. No registers are
* modified, so it is entirely up to the continuation code to figure out
* what to do.
*
* All the routines below use bits of fixup code that are out of line
* with the main instruction path. This means when everything is well,
* we don't even have to jump over them. Further, they do not intrude
* on our cache or tlb entries.
*/
struct exception_table_entry {
unsigned long insn, fixup;
};
/* Returns 0 if exception not found and fixup otherwise. */
extern unsigned long search_exception_table(unsigned long);
/*
* These are the main single-value transfer routines. They automatically
* use the right size if we just have the right pointer type.
*/
#define put_user(x, ptr) \
({ \
int __pu_err = 0; \
typeof(*(ptr)) __pu_val = (x); \
switch (sizeof (*(ptr))) { \
case 1: \
__put_user_asm(__pu_err, __pu_val, ptr, B); \
break; \
case 2: \
__put_user_asm(__pu_err, __pu_val, ptr, W); \
break; \
case 4: \
__put_user_asm(__pu_err, __pu_val, ptr, ); \
break; \
default: \
__pu_err = __put_user_bad(); \
break; \
} \
__pu_err; \
})
/*
* [pregs] = dregs ==> 32bits
* H[pregs] = dregs ==> 16bits
* B[pregs] = dregs ==> 8 bits
*/
#define __put_user(x, ptr) put_user(x, ptr)
static inline int bad_user_access_length(void)
{
panic("bad_user_access_length");
return -1;
}
#define __put_user_bad() (bad_user_access_length(), (-EFAULT))
/*
* Tell gcc we read from memory instead of writing: this is because
* we do not write to any memory gcc knows about, so there are no
* aliasing issues.
*/
#define __ptr(x) ((unsigned long *)(x))
#define __put_user_asm(err,x,ptr,bhw) \
__asm__ (#bhw"[%1] = %0;\n\t" \
: /* no outputs */ \
:"d" (x),"a" (__ptr(ptr)) : "memory")
#define get_user(x, ptr) \
({ \
int __gu_err = 0; \
typeof(*(ptr)) __gu_val = 0; \
switch (sizeof(*(ptr))) { \
case 1: \
__get_user_asm(__gu_err, __gu_val, ptr, B, "=d",(Z)); \
break; \
case 2: \
__get_user_asm(__gu_err, __gu_val, ptr, W, "=r",(Z)); \
break; \
case 4: \
__get_user_asm(__gu_err, __gu_val, ptr, , "=r",); \
break; \
default: \
__gu_val = 0; \
__gu_err = __get_user_bad(); \
break; \
} \
(x) = __gu_val; \
__gu_err; \
})
/* dregs = [pregs] ==> 32bits
* H[pregs] ==> 16bits
* B[pregs] ==> 8 bits
*/
#define __get_user(x, ptr) get_user(x, ptr)
#define __get_user_bad() (bad_user_access_length(), (-EFAULT))
#define __get_user_asm(err,x,ptr,bhw,reg,option) \
__asm__ ("%0 =" #bhw "[%1]"#option";\n\t" \
: "=d" (x) \
: "a" (__ptr(ptr)))
#define copy_from_user(to, from, n) (memcpy(to, from, n), 0)
#define copy_to_user(to, from, n) (memcpy(to, from, n), 0)
#define __copy_from_user(to, from, n) copy_from_user(to, from, n)
#define __copy_to_user(to, from, n) copy_to_user(to, from, n)
#define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n)) return retval; })
#define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n)) return retval; })
/*
* Copy a null terminated string from userspace.
*/
static inline long strncpy_from_user(char *dst, const char *src, long count)
{
char *tmp;
strncpy(dst, src, count);
for (tmp = dst; *tmp && count > 0; tmp++, count--) ;
return (tmp - dst); /* DAVIDM should we count a NUL ? check getname */
}
/*
* Return the size of a string (including the ending 0)
*
* Return 0 on exception, a value greater than N if too long
*/
static inline long strnlen_user(const char *src, long n)
{
return (strlen(src) + 1); /* DAVIDM make safer */
}
#define strlen_user(str) strnlen_user(str, 32767)
/*
* Zero Userspace
*/
static inline unsigned long clear_user(void *to, unsigned long n)
{
memset(to, 0, n);
return (0);
}
#endif