- 根目录:
- arch
- m68k
- include
- asm
- uaccess_mm.h
#ifndef __M68K_UACCESS_H
#define __M68K_UACCESS_H
/*
* User space memory access functions
*/
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <asm/segment.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 __user *addr,
unsigned long size)
{
return 1;
}
/*
* Not all varients of the 68k family support the notion of address spaces.
* The traditional 680x0 parts do, and they use the sfc/dfc registers and
* the "moves" instruction to access user space from kernel space. Other
* family members like ColdFire don't support this, and only have a single
* address space, and use the usual "move" instruction for user space access.
*
* Outside of this difference the user space access functions are the same.
* So lets keep the code simple and just define in what we need to use.
*/
#ifdef CONFIG_CPU_HAS_ADDRESS_SPACES
#define MOVES "moves"
#else
#define MOVES "move"
#endif
/*
* 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;
};
extern int __put_user_bad(void);
extern int __get_user_bad(void);
#define __put_user_asm(res, x, ptr, bwl, reg, err) \
asm volatile ("\n" \
"1: "MOVES"."#bwl" %2,%1\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
" .even\n" \
"10: moveq.l %3,%0\n" \
" jra 2b\n" \
" .previous\n" \
"\n" \
" .section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 1b,10b\n" \
" .long 2b,10b\n" \
" .previous" \
: "+d" (res), "=m" (*(ptr)) \
: #reg (x), "i" (err))
/*
* 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) \
({ \
typeof(*(ptr)) __pu_val = (x); \
int __pu_err = 0; \
__chk_user_ptr(ptr); \
switch (sizeof (*(ptr))) { \
case 1: \
__put_user_asm(__pu_err, __pu_val, ptr, b, d, -EFAULT); \
break; \
case 2: \
__put_user_asm(__pu_err, __pu_val, ptr, w, r, -EFAULT); \
break; \
case 4: \
__put_user_asm(__pu_err, __pu_val, ptr, l, r, -EFAULT); \
break; \
case 8: \
{ \
const void __user *__pu_ptr = (ptr); \
asm volatile ("\n" \
"1: "MOVES".l %2,(%1)+\n" \
"2: "MOVES".l %R2,(%1)\n" \
"3:\n" \
" .section .fixup,\"ax\"\n" \
" .even\n" \
"10: movel %3,%0\n" \
" jra 3b\n" \
" .previous\n" \
"\n" \
" .section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 1b,10b\n" \
" .long 2b,10b\n" \
" .long 3b,10b\n" \
" .previous" \
: "+d" (__pu_err), "+a" (__pu_ptr) \
: "r" (__pu_val), "i" (-EFAULT) \
: "memory"); \
break; \
} \
default: \
__pu_err = __put_user_bad(); \
break; \
} \
__pu_err; \
})
#define put_user(x, ptr) __put_user(x, ptr)
#define __get_user_asm(res, x, ptr, type, bwl, reg, err) ({ \
type __gu_val; \
asm volatile ("\n" \
"1: "MOVES"."#bwl" %2,%1\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
" .even\n" \
"10: move.l %3,%0\n" \
" sub.l %1,%1\n" \
" jra 2b\n" \
" .previous\n" \
"\n" \
" .section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 1b,10b\n" \
" .previous" \
: "+d" (res), "=&" #reg (__gu_val) \
: "m" (*(ptr)), "i" (err)); \
(x) = (__force typeof(*(ptr)))(__force unsigned long)__gu_val; \
})
#define __get_user(x, ptr) \
({ \
int __gu_err = 0; \
__chk_user_ptr(ptr); \
switch (sizeof(*(ptr))) { \
case 1: \
__get_user_asm(__gu_err, x, ptr, u8, b, d, -EFAULT); \
break; \
case 2: \
__get_user_asm(__gu_err, x, ptr, u16, w, r, -EFAULT); \
break; \
case 4: \
__get_user_asm(__gu_err, x, ptr, u32, l, r, -EFAULT); \
break; \
/* case 8: disabled because gcc-4.1 has a broken typeof \
{ \
const void *__gu_ptr = (ptr); \
u64 __gu_val; \
asm volatile ("\n" \
"1: "MOVES".l (%2)+,%1\n" \
"2: "MOVES".l (%2),%R1\n" \
"3:\n" \
" .section .fixup,\"ax\"\n" \
" .even\n" \
"10: move.l %3,%0\n" \
" sub.l %1,%1\n" \
" sub.l %R1,%R1\n" \
" jra 3b\n" \
" .previous\n" \
"\n" \
" .section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 1b,10b\n" \
" .long 2b,10b\n" \
" .previous" \
: "+d" (__gu_err), "=&r" (__gu_val), \
"+a" (__gu_ptr) \
: "i" (-EFAULT) \
: "memory"); \
(x) = (__force typeof(*(ptr)))__gu_val; \
break; \
} */ \
default: \
__gu_err = __get_user_bad(); \
break; \
} \
__gu_err; \
})
#define get_user(x, ptr) __get_user(x, ptr)
unsigned long __generic_copy_from_user(void *to, const void __user *from, unsigned long n);
unsigned long __generic_copy_to_user(void __user *to, const void *from, unsigned long n);
#define __constant_copy_from_user_asm(res, to, from, tmp, n, s1, s2, s3)\
asm volatile ("\n" \
"1: "MOVES"."#s1" (%2)+,%3\n" \
" move."#s1" %3,(%1)+\n" \
"2: "MOVES"."#s2" (%2)+,%3\n" \
" move."#s2" %3,(%1)+\n" \
" .ifnc \""#s3"\",\"\"\n" \
"3: "MOVES"."#s3" (%2)+,%3\n" \
" move."#s3" %3,(%1)+\n" \
" .endif\n" \
"4:\n" \
" .section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 1b,10f\n" \
" .long 2b,20f\n" \
" .ifnc \""#s3"\",\"\"\n" \
" .long 3b,30f\n" \
" .endif\n" \
" .previous\n" \
"\n" \
" .section .fixup,\"ax\"\n" \
" .even\n" \
"10: clr."#s1" (%1)+\n" \
"20: clr."#s2" (%1)+\n" \
" .ifnc \""#s3"\",\"\"\n" \
"30: clr."#s3" (%1)+\n" \
" .endif\n" \
" moveq.l #"#n",%0\n" \
" jra 4b\n" \
" .previous\n" \
: "+d" (res), "+&a" (to), "+a" (from), "=&d" (tmp) \
: : "memory")
static __always_inline unsigned long
__constant_copy_from_user(void *to, const void __user *from, unsigned long n)
{
unsigned long res = 0, tmp;
switch (n) {
case 1:
__get_user_asm(res, *(u8 *)to, (u8 __user *)from, u8, b, d, 1);
break;
case 2:
__get_user_asm(res, *(u16 *)to, (u16 __user *)from, u16, w, r, 2);
break;
case 3:
__constant_copy_from_user_asm(res, to, from, tmp, 3, w, b,);
break;
case 4:
__get_user_asm(res, *(u32 *)to, (u32 __user *)from, u32, l, r, 4);
break;
case 5:
__constant_copy_from_user_asm(res, to, from, tmp, 5, l, b,);
break;
case 6:
__constant_copy_from_user_asm(res, to, from, tmp, 6, l, w,);
break;
case 7:
__constant_copy_from_user_asm(res, to, from, tmp, 7, l, w, b);
break;
case 8:
__constant_copy_from_user_asm(res, to, from, tmp, 8, l, l,);
break;
case 9:
__constant_copy_from_user_asm(res, to, from, tmp, 9, l, l, b);
break;
case 10:
__constant_copy_from_user_asm(res, to, from, tmp, 10, l, l, w);
break;
case 12:
__constant_copy_from_user_asm(res, to, from, tmp, 12, l, l, l);
break;
default:
/* we limit the inlined version to 3 moves */
return __generic_copy_from_user(to, from, n);
}
return res;
}
#define __constant_copy_to_user_asm(res, to, from, tmp, n, s1, s2, s3) \
asm volatile ("\n" \
" move."#s1" (%2)+,%3\n" \
"11: "MOVES"."#s1" %3,(%1)+\n" \
"12: move."#s2" (%2)+,%3\n" \
"21: "MOVES"."#s2" %3,(%1)+\n" \
"22:\n" \
" .ifnc \""#s3"\",\"\"\n" \
" move."#s3" (%2)+,%3\n" \
"31: "MOVES"."#s3" %3,(%1)+\n" \
"32:\n" \
" .endif\n" \
"4:\n" \
"\n" \
" .section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 11b,5f\n" \
" .long 12b,5f\n" \
" .long 21b,5f\n" \
" .long 22b,5f\n" \
" .ifnc \""#s3"\",\"\"\n" \
" .long 31b,5f\n" \
" .long 32b,5f\n" \
" .endif\n" \
" .previous\n" \
"\n" \
" .section .fixup,\"ax\"\n" \
" .even\n" \
"5: moveq.l #"#n",%0\n" \
" jra 4b\n" \
" .previous\n" \
: "+d" (res), "+a" (to), "+a" (from), "=&d" (tmp) \
: : "memory")
static __always_inline unsigned long
__constant_copy_to_user(void __user *to, const void *from, unsigned long n)
{
unsigned long res = 0, tmp;
switch (n) {
case 1:
__put_user_asm(res, *(u8 *)from, (u8 __user *)to, b, d, 1);
break;
case 2:
__put_user_asm(res, *(u16 *)from, (u16 __user *)to, w, r, 2);
break;
case 3:
__constant_copy_to_user_asm(res, to, from, tmp, 3, w, b,);
break;
case 4:
__put_user_asm(res, *(u32 *)from, (u32 __user *)to, l, r, 4);
break;
case 5:
__constant_copy_to_user_asm(res, to, from, tmp, 5, l, b,);
break;
case 6:
__constant_copy_to_user_asm(res, to, from, tmp, 6, l, w,);
break;
case 7:
__constant_copy_to_user_asm(res, to, from, tmp, 7, l, w, b);
break;
case 8:
__constant_copy_to_user_asm(res, to, from, tmp, 8, l, l,);
break;
case 9:
__constant_copy_to_user_asm(res, to, from, tmp, 9, l, l, b);
break;
case 10:
__constant_copy_to_user_asm(res, to, from, tmp, 10, l, l, w);
break;
case 12:
__constant_copy_to_user_asm(res, to, from, tmp, 12, l, l, l);
break;
default:
/* limit the inlined version to 3 moves */
return __generic_copy_to_user(to, from, n);
}
return res;
}
#define __copy_from_user(to, from, n) \
(__builtin_constant_p(n) ? \
__constant_copy_from_user(to, from, n) : \
__generic_copy_from_user(to, from, n))
#define __copy_to_user(to, from, n) \
(__builtin_constant_p(n) ? \
__constant_copy_to_user(to, from, n) : \
__generic_copy_to_user(to, from, n))
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
#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 user_addr_max() \
(segment_eq(get_fs(), USER_DS) ? TASK_SIZE : ~0UL)
extern long strncpy_from_user(char *dst, const char __user *src, long count);
extern __must_check long strlen_user(const char __user *str);
extern __must_check long strnlen_user(const char __user *str, long n);
unsigned long __clear_user(void __user *to, unsigned long n);
#define clear_user __clear_user
#endif /* _M68K_UACCESS_H */