forked from Minki/linux
459 lines
13 KiB
C
459 lines
13 KiB
C
#ifndef __X86_64_UACCESS_H
|
|
#define __X86_64_UACCESS_H
|
|
|
|
/*
|
|
* User space memory access functions
|
|
*/
|
|
#include <linux/compiler.h>
|
|
#include <linux/errno.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(0xFFFFFFFFFFFFFFFFUL)
|
|
#define USER_DS MAKE_MM_SEG(PAGE_OFFSET)
|
|
|
|
#define get_ds() (KERNEL_DS)
|
|
#define get_fs() (current_thread_info()->addr_limit)
|
|
#define set_fs(x) (current_thread_info()->addr_limit = (x))
|
|
|
|
#define segment_eq(a, b) ((a).seg == (b).seg)
|
|
|
|
#define __addr_ok(addr) (!((unsigned long)(addr) & \
|
|
(current_thread_info()->addr_limit.seg)))
|
|
|
|
/*
|
|
* Uhhuh, this needs 65-bit arithmetic. We have a carry..
|
|
*/
|
|
#define __range_not_ok(addr, size) \
|
|
({ \
|
|
unsigned long flag, roksum; \
|
|
__chk_user_ptr(addr); \
|
|
asm("# range_ok\n\r" \
|
|
"addq %3,%1 ; sbbq %0,%0 ; cmpq %1,%4 ; sbbq $0,%0" \
|
|
: "=&r" (flag), "=r" (roksum) \
|
|
: "1" (addr), "g" ((long)(size)), \
|
|
"g" (current_thread_info()->addr_limit.seg)); \
|
|
flag; \
|
|
})
|
|
|
|
#define access_ok(type, addr, size) (__range_not_ok(addr, size) == 0)
|
|
|
|
/*
|
|
* 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 fixup_exception(struct pt_regs *regs);
|
|
|
|
#define ARCH_HAS_SEARCH_EXTABLE
|
|
|
|
/*
|
|
* 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 ugliness 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).
|
|
*/
|
|
|
|
#define __get_user_x(size, ret, x, ptr) \
|
|
asm volatile("call __get_user_" #size \
|
|
: "=a" (ret),"=d" (x) \
|
|
: "c" (ptr) \
|
|
: "r8")
|
|
|
|
/* Careful: we have to cast the result to the type of the pointer
|
|
* for sign reasons */
|
|
|
|
#define get_user(x, ptr) \
|
|
({ \
|
|
unsigned long __val_gu; \
|
|
int __ret_gu; \
|
|
__chk_user_ptr(ptr); \
|
|
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; \
|
|
case 8: \
|
|
__get_user_x(8, __ret_gu, __val_gu, ptr); \
|
|
break; \
|
|
default: \
|
|
__get_user_bad(); \
|
|
break; \
|
|
} \
|
|
(x) = (__force 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(size, ret, x, ptr) \
|
|
asm volatile("call __put_user_" #size \
|
|
:"=a" (ret) \
|
|
:"c" (ptr),"d" (x) \
|
|
:"r8")
|
|
|
|
#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 __get_user_unaligned __get_user
|
|
#define __put_user_unaligned __put_user
|
|
|
|
#define __put_user_nocheck(x, ptr, size) \
|
|
({ \
|
|
int __pu_err; \
|
|
__put_user_size((x), (ptr), (size), __pu_err); \
|
|
__pu_err; \
|
|
})
|
|
|
|
|
|
#define __put_user_check(x, ptr, size) \
|
|
({ \
|
|
int __pu_err; \
|
|
typeof(*(ptr)) __user *__pu_addr = (ptr); \
|
|
switch (size) { \
|
|
case 1: \
|
|
__put_user_x(1, __pu_err, x, __pu_addr); \
|
|
break; \
|
|
case 2: \
|
|
__put_user_x(2, __pu_err, x, __pu_addr); \
|
|
break; \
|
|
case 4: \
|
|
__put_user_x(4, __pu_err, x, __pu_addr); \
|
|
break; \
|
|
case 8: \
|
|
__put_user_x(8, __pu_err, x, __pu_addr); \
|
|
break; \
|
|
default: \
|
|
__put_user_bad(); \
|
|
} \
|
|
__pu_err; \
|
|
})
|
|
|
|
#define __put_user_size(x, ptr, size, retval) \
|
|
do { \
|
|
retval = 0; \
|
|
__chk_user_ptr(ptr); \
|
|
switch (size) { \
|
|
case 1: \
|
|
__put_user_asm(x, ptr, retval, "b", "b", "iq", -EFAULT);\
|
|
break; \
|
|
case 2: \
|
|
__put_user_asm(x, ptr, retval, "w", "w", "ir", -EFAULT);\
|
|
break; \
|
|
case 4: \
|
|
__put_user_asm(x, ptr, retval, "l", "k", "ir", -EFAULT);\
|
|
break; \
|
|
case 8: \
|
|
__put_user_asm(x, ptr, retval, "q", "", "Zr", -EFAULT); \
|
|
break; \
|
|
default: \
|
|
__put_user_bad(); \
|
|
} \
|
|
} while (0)
|
|
|
|
/* FIXME: this hack is definitely wrong -AK */
|
|
struct __large_struct { unsigned long buf[100]; };
|
|
#define __m(x) (*(struct __large_struct __user *)(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, errno) \
|
|
asm volatile("1: mov"itype" %"rtype"1,%2\n" \
|
|
"2:\n" \
|
|
".section .fixup, \"ax\"\n" \
|
|
"3: mov %3,%0\n" \
|
|
" jmp 2b\n" \
|
|
".previous\n" \
|
|
_ASM_EXTABLE(1b, 3b) \
|
|
: "=r"(err) \
|
|
: ltype (x), "m" (__m(addr)), "i" (errno), "0" (err))
|
|
|
|
|
|
#define __get_user_nocheck(x, ptr, size) \
|
|
({ \
|
|
int __gu_err; \
|
|
unsigned long __gu_val; \
|
|
__get_user_size(__gu_val, (ptr), (size), __gu_err); \
|
|
(x) = (__force typeof(*(ptr)))__gu_val; \
|
|
__gu_err; \
|
|
})
|
|
|
|
extern int __get_user_1(void);
|
|
extern int __get_user_2(void);
|
|
extern int __get_user_4(void);
|
|
extern int __get_user_8(void);
|
|
extern int __get_user_bad(void);
|
|
|
|
#define __get_user_size(x, ptr, size, retval) \
|
|
do { \
|
|
retval = 0; \
|
|
__chk_user_ptr(ptr); \
|
|
switch (size) { \
|
|
case 1: \
|
|
__get_user_asm(x, ptr, retval, "b", "b", "=q", -EFAULT);\
|
|
break; \
|
|
case 2: \
|
|
__get_user_asm(x, ptr, retval, "w", "w", "=r", -EFAULT);\
|
|
break; \
|
|
case 4: \
|
|
__get_user_asm(x, ptr, retval, "l", "k", "=r", -EFAULT);\
|
|
break; \
|
|
case 8: \
|
|
__get_user_asm(x, ptr, retval, "q", "", "=r", -EFAULT); \
|
|
break; \
|
|
default: \
|
|
(x) = __get_user_bad(); \
|
|
} \
|
|
} while (0)
|
|
|
|
#define __get_user_asm(x, addr, err, itype, rtype, ltype, errno) \
|
|
asm volatile("1: mov"itype" %2,%"rtype"1\n" \
|
|
"2:\n" \
|
|
".section .fixup, \"ax\"\n" \
|
|
"3: mov %3,%0\n" \
|
|
" xor"itype" %"rtype"1,%"rtype"1\n" \
|
|
" jmp 2b\n" \
|
|
".previous\n" \
|
|
_ASM_EXTABLE(1b, 3b) \
|
|
: "=r" (err), ltype (x) \
|
|
: "m" (__m(addr)), "i"(errno), "0"(err))
|
|
|
|
/*
|
|
* Copy To/From Userspace
|
|
*/
|
|
|
|
/* Handles exceptions in both to and from, but doesn't do access_ok */
|
|
__must_check unsigned long
|
|
copy_user_generic(void *to, const void *from, unsigned len);
|
|
|
|
__must_check unsigned long
|
|
copy_to_user(void __user *to, const void *from, unsigned len);
|
|
__must_check unsigned long
|
|
copy_from_user(void *to, const void __user *from, unsigned len);
|
|
__must_check unsigned long
|
|
copy_in_user(void __user *to, const void __user *from, unsigned len);
|
|
|
|
static __always_inline __must_check
|
|
int __copy_from_user(void *dst, const void __user *src, unsigned size)
|
|
{
|
|
int ret = 0;
|
|
if (!__builtin_constant_p(size))
|
|
return copy_user_generic(dst, (__force void *)src, size);
|
|
switch (size) {
|
|
case 1:__get_user_asm(*(u8 *)dst, (u8 __user *)src,
|
|
ret, "b", "b", "=q", 1);
|
|
return ret;
|
|
case 2:__get_user_asm(*(u16 *)dst, (u16 __user *)src,
|
|
ret, "w", "w", "=r", 2);
|
|
return ret;
|
|
case 4:__get_user_asm(*(u32 *)dst, (u32 __user *)src,
|
|
ret, "l", "k", "=r", 4);
|
|
return ret;
|
|
case 8:__get_user_asm(*(u64 *)dst, (u64 __user *)src,
|
|
ret, "q", "", "=r", 8);
|
|
return ret;
|
|
case 10:
|
|
__get_user_asm(*(u64 *)dst, (u64 __user *)src,
|
|
ret, "q", "", "=r", 16);
|
|
if (unlikely(ret))
|
|
return ret;
|
|
__get_user_asm(*(u16 *)(8 + (char *)dst),
|
|
(u16 __user *)(8 + (char __user *)src),
|
|
ret, "w", "w", "=r", 2);
|
|
return ret;
|
|
case 16:
|
|
__get_user_asm(*(u64 *)dst, (u64 __user *)src,
|
|
ret, "q", "", "=r", 16);
|
|
if (unlikely(ret))
|
|
return ret;
|
|
__get_user_asm(*(u64 *)(8 + (char *)dst),
|
|
(u64 __user *)(8 + (char __user *)src),
|
|
ret, "q", "", "=r", 8);
|
|
return ret;
|
|
default:
|
|
return copy_user_generic(dst, (__force void *)src, size);
|
|
}
|
|
}
|
|
|
|
static __always_inline __must_check
|
|
int __copy_to_user(void __user *dst, const void *src, unsigned size)
|
|
{
|
|
int ret = 0;
|
|
if (!__builtin_constant_p(size))
|
|
return copy_user_generic((__force void *)dst, src, size);
|
|
switch (size) {
|
|
case 1:__put_user_asm(*(u8 *)src, (u8 __user *)dst,
|
|
ret, "b", "b", "iq", 1);
|
|
return ret;
|
|
case 2:__put_user_asm(*(u16 *)src, (u16 __user *)dst,
|
|
ret, "w", "w", "ir", 2);
|
|
return ret;
|
|
case 4:__put_user_asm(*(u32 *)src, (u32 __user *)dst,
|
|
ret, "l", "k", "ir", 4);
|
|
return ret;
|
|
case 8:__put_user_asm(*(u64 *)src, (u64 __user *)dst,
|
|
ret, "q", "", "ir", 8);
|
|
return ret;
|
|
case 10:
|
|
__put_user_asm(*(u64 *)src, (u64 __user *)dst,
|
|
ret, "q", "", "ir", 10);
|
|
if (unlikely(ret))
|
|
return ret;
|
|
asm("":::"memory");
|
|
__put_user_asm(4[(u16 *)src], 4 + (u16 __user *)dst,
|
|
ret, "w", "w", "ir", 2);
|
|
return ret;
|
|
case 16:
|
|
__put_user_asm(*(u64 *)src, (u64 __user *)dst,
|
|
ret, "q", "", "ir", 16);
|
|
if (unlikely(ret))
|
|
return ret;
|
|
asm("":::"memory");
|
|
__put_user_asm(1[(u64 *)src], 1 + (u64 __user *)dst,
|
|
ret, "q", "", "ir", 8);
|
|
return ret;
|
|
default:
|
|
return copy_user_generic((__force void *)dst, src, size);
|
|
}
|
|
}
|
|
|
|
static __always_inline __must_check
|
|
int __copy_in_user(void __user *dst, const void __user *src, unsigned size)
|
|
{
|
|
int ret = 0;
|
|
if (!__builtin_constant_p(size))
|
|
return copy_user_generic((__force void *)dst,
|
|
(__force void *)src, size);
|
|
switch (size) {
|
|
case 1: {
|
|
u8 tmp;
|
|
__get_user_asm(tmp, (u8 __user *)src,
|
|
ret, "b", "b", "=q", 1);
|
|
if (likely(!ret))
|
|
__put_user_asm(tmp, (u8 __user *)dst,
|
|
ret, "b", "b", "iq", 1);
|
|
return ret;
|
|
}
|
|
case 2: {
|
|
u16 tmp;
|
|
__get_user_asm(tmp, (u16 __user *)src,
|
|
ret, "w", "w", "=r", 2);
|
|
if (likely(!ret))
|
|
__put_user_asm(tmp, (u16 __user *)dst,
|
|
ret, "w", "w", "ir", 2);
|
|
return ret;
|
|
}
|
|
|
|
case 4: {
|
|
u32 tmp;
|
|
__get_user_asm(tmp, (u32 __user *)src,
|
|
ret, "l", "k", "=r", 4);
|
|
if (likely(!ret))
|
|
__put_user_asm(tmp, (u32 __user *)dst,
|
|
ret, "l", "k", "ir", 4);
|
|
return ret;
|
|
}
|
|
case 8: {
|
|
u64 tmp;
|
|
__get_user_asm(tmp, (u64 __user *)src,
|
|
ret, "q", "", "=r", 8);
|
|
if (likely(!ret))
|
|
__put_user_asm(tmp, (u64 __user *)dst,
|
|
ret, "q", "", "ir", 8);
|
|
return ret;
|
|
}
|
|
default:
|
|
return copy_user_generic((__force void *)dst,
|
|
(__force void *)src, size);
|
|
}
|
|
}
|
|
|
|
__must_check long
|
|
strncpy_from_user(char *dst, const char __user *src, long count);
|
|
__must_check long
|
|
__strncpy_from_user(char *dst, const char __user *src, long count);
|
|
__must_check long strnlen_user(const char __user *str, long n);
|
|
__must_check long __strnlen_user(const char __user *str, long n);
|
|
__must_check long strlen_user(const char __user *str);
|
|
__must_check unsigned long clear_user(void __user *mem, unsigned long len);
|
|
__must_check unsigned long __clear_user(void __user *mem, unsigned long len);
|
|
|
|
__must_check long __copy_from_user_inatomic(void *dst, const void __user *src,
|
|
unsigned size);
|
|
|
|
static __must_check __always_inline int
|
|
__copy_to_user_inatomic(void __user *dst, const void *src, unsigned size)
|
|
{
|
|
return copy_user_generic((__force void *)dst, src, size);
|
|
}
|
|
|
|
#define ARCH_HAS_NOCACHE_UACCESS 1
|
|
extern long __copy_user_nocache(void *dst, const void __user *src,
|
|
unsigned size, int zerorest);
|
|
|
|
static inline int __copy_from_user_nocache(void *dst, const void __user *src,
|
|
unsigned size)
|
|
{
|
|
might_sleep();
|
|
return __copy_user_nocache(dst, src, size, 1);
|
|
}
|
|
|
|
static inline int __copy_from_user_inatomic_nocache(void *dst,
|
|
const void __user *src,
|
|
unsigned size)
|
|
{
|
|
return __copy_user_nocache(dst, src, size, 0);
|
|
}
|
|
|
|
#endif /* __X86_64_UACCESS_H */
|