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#ifndef __i386_UACCESS_H
#define __i386_UACCESS_H
/*
* User space memory access functions
*/
#include <linux/config.h>
#include <linux/sched.h>
#include <linux/prefetch.h>
#include <asm/page.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_DS MAKE_MM_SEG(0xFFFFFFFF)
#define USER_DS MAKE_MM_SEG(PAGE_OFFSET)
#define get_ds() (KERNEL_DS)
#define get_fs() (current->addr_limit)
#define set_fs(x) (current->addr_limit = (x))
#define segment_eq(a,b) ((a).seg == (b).seg)
extern int __verify_write(const void *, unsigned long);
#define __addr_ok(addr) ((unsigned long)(addr) < (current->addr_limit.seg))
/*
* Uhhuh, this needs 33-bit arithmetic. We have a carry..
*/
#define __range_ok(addr,size) ({ \
unsigned long flag,sum; \
asm("addl %3,%1 ; sbbl %0,%0; cmpl %1,%4; sbbl $0,%0" \
:"=&r" (flag), "=r" (sum) \
:"1" (addr),"g" ((int)(size)),"g" (current->addr_limit.seg)); \
flag; })
#ifdef CONFIG_X86_WP_WORKS_OK
#define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
#else
#define access_ok(type,addr,size) ( (__range_ok(addr,size) == 0) && \
((type) == VERIFY_READ || boot_cpu_data.wp_works_ok || \
segment_eq(get_fs(),KERNEL_DS) || \
__verify_write((void *)(addr),(size))))
#endif
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.
*
* 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 uglyness 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).
*/
extern void __get_user_1(void);
extern void __get_user_2(void);
extern void __get_user_4(void);
#define __get_user_x(size,ret,x,ptr) \
__asm__ __volatile__("call __get_user_" #size \
:"=a" (ret),"=d" (x) \
:"0" (ptr))
/* Careful: we have to cast the result to the type of the pointer for sign reasons */
#define get_user(x,ptr) \
({ int __ret_gu,__val_gu; \
switch(sizeof (*(ptr))) { \
case 1: __get_user_x(1,__ret_gu,__val_gu,ptr); break; \
case 2: __get_user_x(2,__ret_gu,__val_gu,ptr); break; \
case 4: __get_user_x(4,__ret_gu,__val_gu,ptr); break; \
default: __get_user_x(X,__ret_gu,__val_gu,ptr); break; \
} \
(x) = (__typeof__(*(ptr)))__val_gu; \
__ret_gu; \
})
extern void __put_user_1(void);
extern void __put_user_2(void);
extern void __put_user_4(void);
extern void __put_user_8(void);
extern void __put_user_bad(void);
#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)))
#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; \
})
#define __put_user_u64(x, addr, err) \
__asm__ __volatile__( \
"1: movl %%eax,0(%2)\n" \
"2: movl %%edx,4(%2)\n" \
"3:\n" \
".section .fixup,\"ax\"\n" \
"4: movl %3,%0\n" \
" jmp 3b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 1b,4b\n" \
" .long 2b,4b\n" \
".previous" \
: "=r"(err) \
: "A" (x), "r" (addr), "i"(-EFAULT), "0"(err))
#define __put_user_size(x,ptr,size,retval) \
do { \
retval = 0; \
switch (size) { \
case 1: __put_user_asm(x,ptr,retval,"b","b","iq"); break; \
case 2: __put_user_asm(x,ptr,retval,"w","w","ir"); break; \
case 4: __put_user_asm(x,ptr,retval,"l","","ir"); break; \
case 8: __put_user_u64(x,ptr,retval); break; \
default: __put_user_bad(); \
} \
} while (0)
struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct *)(x))
/*
* 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 __put_user_asm(x, addr, err, itype, rtype, ltype) \
__asm__ __volatile__( \
"1: mov"itype" %"rtype"1,%2\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: movl %3,%0\n" \
" jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 1b,3b\n" \
".previous" \
: "=r"(err) \
: ltype (x), "m"(__m(addr)), "i"(-EFAULT), "0"(err))
#define __get_user_nocheck(x,ptr,size) \
({ \
long __gu_err, __gu_val; \
__get_user_size(__gu_val,(ptr),(size),__gu_err); \
(x) = (__typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
extern long __get_user_bad(void);
#define __get_user_size(x,ptr,size,retval) \
do { \
retval = 0; \
switch (size) { \
case 1: __get_user_asm(x,ptr,retval,"b","b","=q"); break; \
case 2: __get_user_asm(x,ptr,retval,"w","w","=r"); break; \
case 4: __get_user_asm(x,ptr,retval,"l","","=r"); break; \
default: (x) = __get_user_bad(); \
} \
} while (0)
#define __get_user_asm(x, addr, err, itype, rtype, ltype) \
__asm__ __volatile__( \
"1: mov"itype" %2,%"rtype"1\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: movl %3,%0\n" \
" xor"itype" %"rtype"1,%"rtype"1\n" \
" jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 1b,3b\n" \
".previous" \
: "=r"(err), ltype (x) \
: "m"(__m(addr)), "i"(-EFAULT), "0"(err))
/*
* Copy To/From Userspace
*/
/* Generic arbitrary sized copy. */
#define __copy_user(to,from,size) \
do { \
int __d0, __d1; \
__asm__ __volatile__( \
"0: rep; movsl\n" \
" movl %3,%0\n" \
"1: rep; movsb\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: lea 0(%3,%0,4),%0\n" \
" jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,3b\n" \
" .long 1b,2b\n" \
".previous" \
: "=&c"(size), "=&D" (__d0), "=&S" (__d1) \
: "r"(size & 3), "0"(size / 4), "1"(to), "2"(from) \
: "memory"); \
} while (0)
#define __copy_user_zeroing(to,from,size) \
do { \
int __d0, __d1; \
__asm__ __volatile__( \
"0: rep; movsl\n" \
" movl %3,%0\n" \
"1: rep; movsb\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: lea 0(%3,%0,4),%0\n" \
"4: pushl %0\n" \
" pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" rep; stosb\n" \
" popl %%eax\n" \
" popl %0\n" \
" jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,3b\n" \
" .long 1b,4b\n" \
".previous" \
: "=&c"(size), "=&D" (__d0), "=&S" (__d1) \
: "r"(size & 3), "0"(size / 4), "1"(to), "2"(from) \
: "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;
}
/* Optimize just a little bit when we know the size of the move. */
#define __constant_copy_user(to, from, size) \
do { \
int __d0, __d1; \
switch (size & 3) { \
default: \
__asm__ __volatile__( \
"0: rep; movsl\n" \
"1:\n" \
".section .fixup,\"ax\"\n" \
"2: shl $2,%0\n" \
" jmp 1b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,2b\n" \
".previous" \
: "=c"(size), "=&S" (__d0), "=&D" (__d1)\
: "1"(from), "2"(to), "0"(size/4) \
: "memory"); \
break; \
case 1: \
__asm__ __volatile__( \
"0: rep; movsl\n" \
"1: movsb\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: shl $2,%0\n" \
"4: incl %0\n" \
" jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,3b\n" \
" .long 1b,4b\n" \
".previous" \
: "=c"(size), "=&S" (__d0), "=&D" (__d1)\
: "1"(from), "2"(to), "0"(size/4) \
: "memory"); \
break; \
case 2: \
__asm__ __volatile__( \
"0: rep; movsl\n" \
"1: movsw\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: shl $2,%0\n" \
"4: addl $2,%0\n" \
" jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,3b\n" \
" .long 1b,4b\n" \
".previous" \
: "=c"(size), "=&S" (__d0), "=&D" (__d1)\
: "1"(from), "2"(to), "0"(size/4) \
: "memory"); \
break; \
case 3: \
__asm__ __volatile__( \
"0: rep; movsl\n" \
"1: movsw\n" \
"2: movsb\n" \
"3:\n" \
".section .fixup,\"ax\"\n" \
"4: shl $2,%0\n" \
"5: addl $2,%0\n" \
"6: incl %0\n" \
" jmp 3b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,4b\n" \
" .long 1b,5b\n" \
" .long 2b,6b\n" \
".previous" \
: "=c"(size), "=&S" (__d0), "=&D" (__d1)\
: "1"(from), "2"(to), "0"(size/4) \
: "memory"); \
break; \
} \
} while (0)
/* Optimize just a little bit when we know the size of the move. */
#define __constant_copy_user_zeroing(to, from, size) \
do { \
int __d0, __d1; \
switch (size & 3) { \
default: \
__asm__ __volatile__( \
"0: rep; movsl\n" \
"1:\n" \
".section .fixup,\"ax\"\n" \
"2: pushl %0\n" \
" pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" rep; stosl\n" \
" popl %%eax\n" \
" popl %0\n" \
" shl $2,%0\n" \
" jmp 1b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,2b\n" \
".previous" \
: "=c"(size), "=&S" (__d0), "=&D" (__d1)\
: "1"(from), "2"(to), "0"(size/4) \
: "memory"); \
break; \
case 1: \
__asm__ __volatile__( \
"0: rep; movsl\n" \
"1: movsb\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: pushl %0\n" \
" pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" rep; stosl\n" \
" stosb\n" \
" popl %%eax\n" \
" popl %0\n" \
" shl $2,%0\n" \
" incl %0\n" \
" jmp 2b\n" \
"4: pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" stosb\n" \
" popl %%eax\n" \
" incl %0\n" \
" jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,3b\n" \
" .long 1b,4b\n" \
".previous" \
: "=c"(size), "=&S" (__d0), "=&D" (__d1)\
: "1"(from), "2"(to), "0"(size/4) \
: "memory"); \
break; \
case 2: \
__asm__ __volatile__( \
"0: rep; movsl\n" \
"1: movsw\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: pushl %0\n" \
" pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" rep; stosl\n" \
" stosw\n" \
" popl %%eax\n" \
" popl %0\n" \
" shl $2,%0\n" \
" addl $2,%0\n" \
" jmp 2b\n" \
"4: pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" stosw\n" \
" popl %%eax\n" \
" addl $2,%0\n" \
" jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,3b\n" \
" .long 1b,4b\n" \
".previous" \
: "=c"(size), "=&S" (__d0), "=&D" (__d1)\
: "1"(from), "2"(to), "0"(size/4) \
: "memory"); \
break; \
case 3: \
__asm__ __volatile__( \
"0: rep; movsl\n" \
"1: movsw\n" \
"2: movsb\n" \
"3:\n" \
".section .fixup,\"ax\"\n" \
"4: pushl %0\n" \
" pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" rep; stosl\n" \
" stosw\n" \
" stosb\n" \
" popl %%eax\n" \
" popl %0\n" \
" shl $2,%0\n" \
" addl $3,%0\n" \
" jmp 2b\n" \
"5: pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" stosw\n" \
" stosb\n" \
" popl %%eax\n" \
" addl $3,%0\n" \
" jmp 2b\n" \
"6: pushl %%eax\n" \
" xorl %%eax,%%eax\n" \
" stosb\n" \
" popl %%eax\n" \
" incl %0\n" \
" jmp 3b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,4b\n" \
" .long 1b,5b\n" \
" .long 2b,6b\n" \
".previous" \
: "=c"(size), "=&S" (__d0), "=&D" (__d1)\
: "1"(from), "2"(to), "0"(size/4) \
: "memory"); \
break; \
} \
} while (0)
unsigned long __generic_copy_to_user(void *, const void *, unsigned long);
unsigned long __generic_copy_from_user(void *, const void *, unsigned long);
static inline unsigned long
__constant_copy_to_user(void *to, const void *from, unsigned long n)
{
prefetch(from);
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);
else
memset(to, 0, 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;
}
#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_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_nocheck((to),(from),(n)) : \
__generic_copy_to_user_nocheck((to),(from),(n)))
#define __copy_from_user(to,from,n) \
(__builtin_constant_p(n) ? \
__constant_copy_from_user_nocheck((to),(from),(n)) : \
__generic_copy_from_user_nocheck((to),(from),(n)))
long strncpy_from_user(char *dst, const char *src, long count);
long __strncpy_from_user(char *dst, const char *src, long count);
#define strlen_user(str) strnlen_user(str, ~0UL >> 1)
long strnlen_user(const char *str, long n);
unsigned long clear_user(void *mem, unsigned long len);
unsigned long __clear_user(void *mem, unsigned long len);
#endif /* __i386_UACCESS_H */
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