491 lines
13 KiB
C
491 lines
13 KiB
C
![]() |
/* MN10300 userspace access functions
|
||
|
*
|
||
|
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
|
||
|
* Written by David Howells (dhowells@redhat.com)
|
||
|
*
|
||
|
* This program is free software; you can redistribute it and/or
|
||
|
* modify it under the terms of the GNU General Public Licence
|
||
|
* as published by the Free Software Foundation; either version
|
||
|
* 2 of the Licence, or (at your option) any later version.
|
||
|
*/
|
||
|
#ifndef _ASM_UACCESS_H
|
||
|
#define _ASM_UACCESS_H
|
||
|
|
||
|
/*
|
||
|
* User space memory access functions
|
||
|
*/
|
||
|
#include <linux/sched.h>
|
||
|
#include <asm/page.h>
|
||
|
#include <asm/pgtable.h>
|
||
|
#include <asm/errno.h>
|
||
|
|
||
|
#define VERIFY_READ 0
|
||
|
#define VERIFY_WRITE 1
|
||
|
|
||
|
/*
|
||
|
* 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) })
|
||
|
|
||
|
#define KERNEL_XDS MAKE_MM_SEG(0xBFFFFFFF)
|
||
|
#define KERNEL_DS MAKE_MM_SEG(0x9FFFFFFF)
|
||
|
#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 __kernel_ds_p() (current_thread_info()->addr_limit.seg == 0x9FFFFFFF)
|
||
|
|
||
|
#define segment_eq(a, b) ((a).seg == (b).seg)
|
||
|
|
||
|
#define __addr_ok(addr) \
|
||
|
((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))
|
||
|
|
||
|
/*
|
||
|
* check that a range of addresses falls within the current address limit
|
||
|
*/
|
||
|
static inline int ___range_ok(unsigned long addr, unsigned int size)
|
||
|
{
|
||
|
int flag = 1, tmp;
|
||
|
|
||
|
asm(" add %3,%1 \n" /* set C-flag if addr + size > 4Gb */
|
||
|
" bcs 0f \n"
|
||
|
" cmp %4,%1 \n" /* jump if addr+size>limit (error) */
|
||
|
" bhi 0f \n"
|
||
|
" clr %0 \n" /* mark okay */
|
||
|
"0: \n"
|
||
|
: "=r"(flag), "=&r"(tmp)
|
||
|
: "1"(addr), "ir"(size),
|
||
|
"r"(current_thread_info()->addr_limit.seg), "0"(flag)
|
||
|
: "cc"
|
||
|
);
|
||
|
|
||
|
return flag;
|
||
|
}
|
||
|
|
||
|
#define __range_ok(addr, size) ___range_ok((unsigned long)(addr), (u32)(size))
|
||
|
|
||
|
#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0)
|
||
|
#define __access_ok(addr, size) (__range_ok((addr), (size)) == 0)
|
||
|
|
||
|
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 int fixup_exception(struct pt_regs *regs);
|
||
|
|
||
|
#define put_user(x, ptr) __put_user_check((x), (ptr), sizeof(*(ptr)))
|
||
|
#define get_user(x, ptr) __get_user_check((x), (ptr), sizeof(*(ptr)))
|
||
|
|
||
|
/*
|
||
|
* The "__xxx" versions do not do address space checking, useful when
|
||
|
* doing multiple accesses to the same area (the user has to do the
|
||
|
* checks by hand with "access_ok()")
|
||
|
*/
|
||
|
#define __put_user(x, ptr) __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
|
||
|
#define __get_user(x, ptr) __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
|
||
|
|
||
|
/*
|
||
|
* The "xxx_ret" versions return constant specified in third argument, if
|
||
|
* something bad happens. These macros can be optimized for the
|
||
|
* case of just returning from the function xxx_ret is used.
|
||
|
*/
|
||
|
|
||
|
#define put_user_ret(x, ptr, ret) \
|
||
|
({ if (put_user((x), (ptr))) return (ret); })
|
||
|
#define get_user_ret(x, ptr, ret) \
|
||
|
({ if (get_user((x), (ptr))) return (ret); })
|
||
|
#define __put_user_ret(x, ptr, ret) \
|
||
|
({ if (__put_user((x), (ptr))) return (ret); })
|
||
|
#define __get_user_ret(x, ptr, ret) \
|
||
|
({ if (__get_user((x), (ptr))) return (ret); })
|
||
|
|
||
|
struct __large_struct { unsigned long buf[100]; };
|
||
|
#define __m(x) (*(struct __large_struct *)(x))
|
||
|
|
||
|
#define __get_user_nocheck(x, ptr, size) \
|
||
|
({ \
|
||
|
__typeof(*(ptr)) __gu_val; \
|
||
|
unsigned long __gu_addr; \
|
||
|
int __gu_err; \
|
||
|
__gu_addr = (unsigned long) (ptr); \
|
||
|
switch (size) { \
|
||
|
case 1: __get_user_asm("bu"); break; \
|
||
|
case 2: __get_user_asm("hu"); break; \
|
||
|
case 4: __get_user_asm("" ); break; \
|
||
|
default: __get_user_unknown(); break; \
|
||
|
} \
|
||
|
x = (__typeof__(*(ptr))) __gu_val; \
|
||
|
__gu_err; \
|
||
|
})
|
||
|
|
||
|
#define __get_user_check(x, ptr, size) \
|
||
|
({ \
|
||
|
__typeof__(*(ptr)) __gu_val; \
|
||
|
unsigned long __gu_addr; \
|
||
|
int __gu_err; \
|
||
|
__gu_addr = (unsigned long) (ptr); \
|
||
|
if (likely(__access_ok(__gu_addr,size))) { \
|
||
|
switch (size) { \
|
||
|
case 1: __get_user_asm("bu"); break; \
|
||
|
case 2: __get_user_asm("hu"); break; \
|
||
|
case 4: __get_user_asm("" ); break; \
|
||
|
default: __get_user_unknown(); break; \
|
||
|
} \
|
||
|
} \
|
||
|
else { \
|
||
|
__gu_err = -EFAULT; \
|
||
|
__gu_val = 0; \
|
||
|
} \
|
||
|
x = (__typeof__(*(ptr))) __gu_val; \
|
||
|
__gu_err; \
|
||
|
})
|
||
|
|
||
|
#define __get_user_asm(INSN) \
|
||
|
({ \
|
||
|
asm volatile( \
|
||
|
"1:\n" \
|
||
|
" mov"INSN" %2,%1\n" \
|
||
|
" mov 0,%0\n" \
|
||
|
"2:\n" \
|
||
|
" .section .fixup,\"ax\"\n" \
|
||
|
"3:\n\t" \
|
||
|
" mov %3,%0\n" \
|
||
|
" jmp 2b\n" \
|
||
|
" .previous\n" \
|
||
|
" .section __ex_table,\"a\"\n" \
|
||
|
" .balign 4\n" \
|
||
|
" .long 1b, 3b\n" \
|
||
|
" .previous" \
|
||
|
: "=&r" (__gu_err), "=&r" (__gu_val) \
|
||
|
: "m" (__m(__gu_addr)), "i" (-EFAULT)); \
|
||
|
})
|
||
|
|
||
|
extern int __get_user_unknown(void);
|
||
|
|
||
|
#define __put_user_nocheck(x, ptr, size) \
|
||
|
({ \
|
||
|
union { \
|
||
|
__typeof__(*(ptr)) val; \
|
||
|
u32 bits[2]; \
|
||
|
} __pu_val; \
|
||
|
unsigned long __pu_addr; \
|
||
|
int __pu_err; \
|
||
|
__pu_val.val = (x); \
|
||
|
__pu_addr = (unsigned long) (ptr); \
|
||
|
switch (size) { \
|
||
|
case 1: __put_user_asm("bu"); break; \
|
||
|
case 2: __put_user_asm("hu"); break; \
|
||
|
case 4: __put_user_asm("" ); break; \
|
||
|
case 8: __put_user_asm8(); break; \
|
||
|
default: __pu_err = __put_user_unknown(); break; \
|
||
|
} \
|
||
|
__pu_err; \
|
||
|
})
|
||
|
|
||
|
#define __put_user_check(x, ptr, size) \
|
||
|
({ \
|
||
|
union { \
|
||
|
__typeof__(*(ptr)) val; \
|
||
|
u32 bits[2]; \
|
||
|
} __pu_val; \
|
||
|
unsigned long __pu_addr; \
|
||
|
int __pu_err; \
|
||
|
__pu_val.val = (x); \
|
||
|
__pu_addr = (unsigned long) (ptr); \
|
||
|
if (likely(__access_ok(__pu_addr, size))) { \
|
||
|
switch (size) { \
|
||
|
case 1: __put_user_asm("bu"); break; \
|
||
|
case 2: __put_user_asm("hu"); break; \
|
||
|
case 4: __put_user_asm("" ); break; \
|
||
|
case 8: __put_user_asm8(); break; \
|
||
|
default: __pu_err = __put_user_unknown(); break; \
|
||
|
} \
|
||
|
} \
|
||
|
else { \
|
||
|
__pu_err = -EFAULT; \
|
||
|
} \
|
||
|
__pu_err; \
|
||
|
})
|
||
|
|
||
|
#define __put_user_asm(INSN) \
|
||
|
({ \
|
||
|
asm volatile( \
|
||
|
"1:\n" \
|
||
|
" mov"INSN" %1,%2\n" \
|
||
|
" mov 0,%0\n" \
|
||
|
"2:\n" \
|
||
|
" .section .fixup,\"ax\"\n" \
|
||
|
"3:\n" \
|
||
|
" mov %3,%0\n" \
|
||
|
" jmp 2b\n" \
|
||
|
" .previous\n" \
|
||
|
" .section __ex_table,\"a\"\n" \
|
||
|
" .balign 4\n" \
|
||
|
" .long 1b, 3b\n" \
|
||
|
" .previous" \
|
||
|
: "=&r" (__pu_err) \
|
||
|
: "r" (__pu_val.val), "m" (__m(__pu_addr)), \
|
||
|
"i" (-EFAULT) \
|
||
|
); \
|
||
|
})
|
||
|
|
||
|
#define __put_user_asm8() \
|
||
|
({ \
|
||
|
asm volatile( \
|
||
|
"1: mov %1,%3 \n" \
|
||
|
"2: mov %2,%4 \n" \
|
||
|
" mov 0,%0 \n" \
|
||
|
"3: \n" \
|
||
|
" .section .fixup,\"ax\" \n" \
|
||
|
"4: \n" \
|
||
|
" mov %5,%0 \n" \
|
||
|
" jmp 2b \n" \
|
||
|
" .previous \n" \
|
||
|
" .section __ex_table,\"a\"\n" \
|
||
|
" .balign 4 \n" \
|
||
|
" .long 1b, 4b \n" \
|
||
|
" .long 2b, 4b \n" \
|
||
|
" .previous \n" \
|
||
|
: "=&r" (__pu_err) \
|
||
|
: "r" (__pu_val.bits[0]), "r" (__pu_val.bits[1]), \
|
||
|
"m" (__m(__pu_addr)), "m" (__m(__pu_addr+4)), \
|
||
|
"i" (-EFAULT) \
|
||
|
); \
|
||
|
})
|
||
|
|
||
|
extern int __put_user_unknown(void);
|
||
|
|
||
|
|
||
|
/*
|
||
|
* Copy To/From Userspace
|
||
|
*/
|
||
|
/* Generic arbitrary sized copy. */
|
||
|
#define __copy_user(to, from, size) \
|
||
|
do { \
|
||
|
if (size) { \
|
||
|
void *__to = to; \
|
||
|
const void *__from = from; \
|
||
|
int w; \
|
||
|
asm volatile( \
|
||
|
"0: movbu (%0),%3;\n" \
|
||
|
"1: movbu %3,(%1);\n" \
|
||
|
" inc %0;\n" \
|
||
|
" inc %1;\n" \
|
||
|
" add -1,%2;\n" \
|
||
|
" bne 0b;\n" \
|
||
|
"2:\n" \
|
||
|
" .section .fixup,\"ax\"\n" \
|
||
|
"3: jmp 2b\n" \
|
||
|
" .previous\n" \
|
||
|
" .section __ex_table,\"a\"\n" \
|
||
|
" .balign 4\n" \
|
||
|
" .long 0b,3b\n" \
|
||
|
" .long 1b,3b\n" \
|
||
|
" .previous\n" \
|
||
|
: "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\
|
||
|
: "0"(__from), "1"(__to), "2"(size) \
|
||
|
: "memory"); \
|
||
|
} \
|
||
|
} while (0)
|
||
|
|
||
|
#define __copy_user_zeroing(to, from, size) \
|
||
|
do { \
|
||
|
if (size) { \
|
||
|
void *__to = to; \
|
||
|
const void *__from = from; \
|
||
|
int w; \
|
||
|
asm volatile( \
|
||
|
"0: movbu (%0),%3;\n" \
|
||
|
"1: movbu %3,(%1);\n" \
|
||
|
" inc %0;\n" \
|
||
|
" inc %1;\n" \
|
||
|
" add -1,%2;\n" \
|
||
|
" bne 0b;\n" \
|
||
|
"2:\n" \
|
||
|
" .section .fixup,\"ax\"\n" \
|
||
|
"3:\n" \
|
||
|
" mov %2,%0\n" \
|
||
|
" clr %3\n" \
|
||
|
"4: movbu %3,(%1);\n" \
|
||
|
" inc %1;\n" \
|
||
|
" add -1,%2;\n" \
|
||
|
" bne 4b;\n" \
|
||
|
" mov %0,%2\n" \
|
||
|
" jmp 2b\n" \
|
||
|
" .previous\n" \
|
||
|
" .section __ex_table,\"a\"\n" \
|
||
|
" .balign 4\n" \
|
||
|
" .long 0b,3b\n" \
|
||
|
" .long 1b,3b\n" \
|
||
|
" .previous\n" \
|
||
|
: "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\
|
||
|
: "0"(__from), "1"(__to), "2"(size) \
|
||
|
: "memory"); \
|
||
|
} \
|
||
|
} while (0)
|
||
|
|
||
|
/* We let the __ versions of copy_from/to_user inline, because they're often
|
||
|
* used in fast paths and have only a small space overhead.
|
||
|
*/
|
||
|
static inline
|
||
|
unsigned long __generic_copy_from_user_nocheck(void *to, const void *from,
|
||
|
unsigned long n)
|
||
|
{
|
||
|
__copy_user_zeroing(to, from, n);
|
||
|
return n;
|
||
|
}
|
||
|
|
||
|
static inline
|
||
|
unsigned long __generic_copy_to_user_nocheck(void *to, const void *from,
|
||
|
unsigned long n)
|
||
|
{
|
||
|
__copy_user(to, from, n);
|
||
|
return n;
|
||
|
}
|
||
|
|
||
|
|
||
|
#if 0
|
||
|
#error don't use - these macros don't increment to & from pointers
|
||
|
/* Optimize just a little bit when we know the size of the move. */
|
||
|
#define __constant_copy_user(to, from, size) \
|
||
|
do { \
|
||
|
asm volatile( \
|
||
|
" mov %0,a0;\n" \
|
||
|
"0: movbu (%1),d3;\n" \
|
||
|
"1: movbu d3,(%2);\n" \
|
||
|
" add -1,a0;\n" \
|
||
|
" bne 0b;\n" \
|
||
|
"2:;" \
|
||
|
".section .fixup,\"ax\"\n" \
|
||
|
"3: jmp 2b\n" \
|
||
|
".previous\n" \
|
||
|
".section __ex_table,\"a\"\n" \
|
||
|
" .balign 4\n" \
|
||
|
" .long 0b,3b\n" \
|
||
|
" .long 1b,3b\n" \
|
||
|
".previous" \
|
||
|
: \
|
||
|
: "d"(size), "d"(to), "d"(from) \
|
||
|
: "d3", "a0"); \
|
||
|
} while (0)
|
||
|
|
||
|
/* Optimize just a little bit when we know the size of the move. */
|
||
|
#define __constant_copy_user_zeroing(to, from, size) \
|
||
|
do { \
|
||
|
asm volatile( \
|
||
|
" mov %0,a0;\n" \
|
||
|
"0: movbu (%1),d3;\n" \
|
||
|
"1: movbu d3,(%2);\n" \
|
||
|
" add -1,a0;\n" \
|
||
|
" bne 0b;\n" \
|
||
|
"2:;" \
|
||
|
".section .fixup,\"ax\"\n" \
|
||
|
"3: jmp 2b\n" \
|
||
|
".previous\n" \
|
||
|
".section __ex_table,\"a\"\n" \
|
||
|
" .balign 4\n" \
|
||
|
" .long 0b,3b\n" \
|
||
|
" .long 1b,3b\n" \
|
||
|
".previous" \
|
||
|
: \
|
||
|
: "d"(size), "d"(to), "d"(from) \
|
||
|
: "d3", "a0"); \
|
||
|
} while (0)
|
||
|
|
||
|
static inline
|
||
|
unsigned long __constant_copy_to_user(void *to, const void *from,
|
||
|
unsigned long n)
|
||
|
{
|
||
|
if (access_ok(VERIFY_WRITE, to, n))
|
||
|
__constant_copy_user(to, from, n);
|
||
|
return n;
|
||
|
}
|
||
|
|
||
|
static inline
|
||
|
unsigned long __constant_copy_from_user(void *to, const void *from,
|
||
|
unsigned long n)
|
||
|
{
|
||
|
if (access_ok(VERIFY_READ, from, n))
|
||
|
__constant_copy_user_zeroing(to, from, n);
|
||
|
return n;
|
||
|
}
|
||
|
|
||
|
static inline
|
||
|
unsigned long __constant_copy_to_user_nocheck(void *to, const void *from,
|
||
|
unsigned long n)
|
||
|
{
|
||
|
__constant_copy_user(to, from, n);
|
||
|
return n;
|
||
|
}
|
||
|
|
||
|
static inline
|
||
|
unsigned long __constant_copy_from_user_nocheck(void *to, const void *from,
|
||
|
unsigned long n)
|
||
|
{
|
||
|
__constant_copy_user_zeroing(to, from, n);
|
||
|
return n;
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
extern unsigned long __generic_copy_to_user(void __user *, const void *,
|
||
|
unsigned long);
|
||
|
extern unsigned long __generic_copy_from_user(void *, const void __user *,
|
||
|
unsigned long);
|
||
|
|
||
|
#define __copy_to_user_inatomic(to, from, n) \
|
||
|
__generic_copy_to_user_nocheck((to), (from), (n))
|
||
|
#define __copy_from_user_inatomic(to, from, n) \
|
||
|
__generic_copy_from_user_nocheck((to), (from), (n))
|
||
|
|
||
|
#define __copy_to_user(to, from, n) \
|
||
|
({ \
|
||
|
might_sleep(); \
|
||
|
__copy_to_user_inatomic((to), (from), (n)); \
|
||
|
})
|
||
|
|
||
|
#define __copy_from_user(to, from, n) \
|
||
|
({ \
|
||
|
might_sleep(); \
|
||
|
__copy_from_user_inatomic((to), (from), (n)); \
|
||
|
})
|
||
|
|
||
|
|
||
|
#define copy_to_user(to, from, n) __generic_copy_to_user((to), (from), (n))
|
||
|
#define copy_from_user(to, from, n) __generic_copy_from_user((to), (from), (n))
|
||
|
|
||
|
extern long strncpy_from_user(char *dst, const char __user *src, long count);
|
||
|
extern long __strncpy_from_user(char *dst, const char __user *src, long count);
|
||
|
extern long strnlen_user(const char __user *str, long n);
|
||
|
#define strlen_user(str) strnlen_user(str, ~0UL >> 1)
|
||
|
extern unsigned long clear_user(void __user *mem, unsigned long len);
|
||
|
extern unsigned long __clear_user(void __user *mem, unsigned long len);
|
||
|
|
||
|
#endif /* _ASM_UACCESS_H */
|