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ubuntu-linux-kernel/arch/mips/include/asm/uaccess.h

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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Copyright (C) 2007 Maciej W. Rozycki
* Copyright (C) 2014, Imagination Technologies Ltd.
*/
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H
#include <linux/kernel.h>
#include <linux/string.h>
#include <asm/asm-eva.h>
#include <asm/extable.h>
/*
* 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.
*/
#ifdef CONFIG_32BIT
#ifdef CONFIG_KVM_GUEST
#define __UA_LIMIT 0x40000000UL
#else
#define __UA_LIMIT 0x80000000UL
#endif
#define __UA_ADDR ".word"
#define __UA_LA "la"
#define __UA_ADDU "addu"
#define __UA_t0 "$8"
#define __UA_t1 "$9"
#endif /* CONFIG_32BIT */
#ifdef CONFIG_64BIT
extern u64 __ua_limit;
#define __UA_LIMIT __ua_limit
#define __UA_ADDR ".dword"
#define __UA_LA "dla"
#define __UA_ADDU "daddu"
#define __UA_t0 "$12"
#define __UA_t1 "$13"
#endif /* CONFIG_64BIT */
/*
* USER_DS is a bitmask that has the bits set that may not be set in a valid
* userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
* the arithmetic we're doing only works if the limit is a power of two, so
* we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
* address in this range it's the process's problem, not ours :-)
*/
#ifdef CONFIG_KVM_GUEST
#define KERNEL_DS ((mm_segment_t) { 0x80000000UL })
#define USER_DS ((mm_segment_t) { 0xC0000000UL })
#else
#define KERNEL_DS ((mm_segment_t) { 0UL })
#define USER_DS ((mm_segment_t) { __UA_LIMIT })
#endif
#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)
/*
* eva_kernel_access() - determine whether kernel memory access on an EVA system
*
* Determines whether memory accesses should be performed to kernel memory
* on a system using Extended Virtual Addressing (EVA).
*
* Return: true if a kernel memory access on an EVA system, else false.
*/
static inline bool eva_kernel_access(void)
{
if (!IS_ENABLED(CONFIG_EVA))
return false;
return uaccess_kernel();
}
/*
* Is a address valid? This does a straightforward calculation rather
* than tests.
*
* Address valid if:
* - "addr" doesn't have any high-bits set
* - AND "size" doesn't have any high-bits set
* - AND "addr+size" doesn't have any high-bits set
* - OR we are in kernel mode.
*
* __ua_size() is a trick to avoid runtime checking of positive constant
* sizes; for those we already know at compile time that the size is ok.
*/
#define __ua_size(size) \
((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
/*
* access_ok: - Checks if a user space pointer is valid
* @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
* %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
* to write to a block, it is always safe to read from it.
* @addr: User space pointer to start of block to check
* @size: Size of block to check
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Checks if a pointer to a block of memory in user space is valid.
*
* Returns true (nonzero) if the memory block may be valid, false (zero)
* if it is definitely invalid.
*
* Note that, depending on architecture, this function probably just
* checks that the pointer is in the user space range - after calling
* this function, memory access functions may still return -EFAULT.
*/
static inline int __access_ok(const void __user *p, unsigned long size)
{
unsigned long addr = (unsigned long)p;
return (get_fs().seg & (addr | (addr + size) | __ua_size(size))) == 0;
}
#define access_ok(type, addr, size) \
likely(__access_ok((addr), (size)))
/*
* put_user: - Write a simple value into user space.
* @x: Value to copy to user space.
* @ptr: Destination address, in user space.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple value from kernel space to user
* space. It supports simple types like char and int, but not larger
* data types like structures or arrays.
*
* @ptr must have pointer-to-simple-variable type, and @x must be assignable
* to the result of dereferencing @ptr.
*
* Returns zero on success, or -EFAULT on error.
*/
#define put_user(x,ptr) \
__put_user_check((x), (ptr), sizeof(*(ptr)))
/*
* get_user: - Get a simple variable from user space.
* @x: Variable to store result.
* @ptr: Source address, in user space.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple variable from user space to kernel
* space. It supports simple types like char and int, but not larger
* data types like structures or arrays.
*
* @ptr must have pointer-to-simple-variable type, and the result of
* dereferencing @ptr must be assignable to @x without a cast.
*
* Returns zero on success, or -EFAULT on error.
* On error, the variable @x is set to zero.
*/
#define get_user(x,ptr) \
__get_user_check((x), (ptr), sizeof(*(ptr)))
/*
* __put_user: - Write a simple value into user space, with less checking.
* @x: Value to copy to user space.
* @ptr: Destination address, in user space.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple value from kernel space to user
* space. It supports simple types like char and int, but not larger
* data types like structures or arrays.
*
* @ptr must have pointer-to-simple-variable type, and @x must be assignable
* to the result of dereferencing @ptr.
*
* Caller must check the pointer with access_ok() before calling this
* function.
*
* Returns zero on success, or -EFAULT on error.
*/
#define __put_user(x,ptr) \
__put_user_nocheck((x), (ptr), sizeof(*(ptr)))
/*
* __get_user: - Get a simple variable from user space, with less checking.
* @x: Variable to store result.
* @ptr: Source address, in user space.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* This macro copies a single simple variable from user space to kernel
* space. It supports simple types like char and int, but not larger
* data types like structures or arrays.
*
* @ptr must have pointer-to-simple-variable type, and the result of
* dereferencing @ptr must be assignable to @x without a cast.
*
* Caller must check the pointer with access_ok() before calling this
* function.
*
* Returns zero on success, or -EFAULT on error.
* On error, the variable @x is set to zero.
*/
#define __get_user(x,ptr) \
__get_user_nocheck((x), (ptr), sizeof(*(ptr)))
struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct __user *)(x))
/*
* Yuck. We need two variants, one for 64bit operation and one
* for 32 bit mode and old iron.
*/
#ifndef CONFIG_EVA
#define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr)
#else
/*
* Kernel specific functions for EVA. We need to use normal load instructions
* to read data from kernel when operating in EVA mode. We use these macros to
* avoid redefining __get_user_asm for EVA.
*/
#undef _loadd
#undef _loadw
#undef _loadh
#undef _loadb
#ifdef CONFIG_32BIT
#define _loadd _loadw
#else
#define _loadd(reg, addr) "ld " reg ", " addr
#endif
#define _loadw(reg, addr) "lw " reg ", " addr
#define _loadh(reg, addr) "lh " reg ", " addr
#define _loadb(reg, addr) "lb " reg ", " addr
#define __get_kernel_common(val, size, ptr) \
do { \
switch (size) { \
case 1: __get_data_asm(val, _loadb, ptr); break; \
case 2: __get_data_asm(val, _loadh, ptr); break; \
case 4: __get_data_asm(val, _loadw, ptr); break; \
case 8: __GET_DW(val, _loadd, ptr); break; \
default: __get_user_unknown(); break; \
} \
} while (0)
#endif
#ifdef CONFIG_32BIT
#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
#endif
#ifdef CONFIG_64BIT
#define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
#endif
extern void __get_user_unknown(void);
#define __get_user_common(val, size, ptr) \
do { \
switch (size) { \
case 1: __get_data_asm(val, user_lb, ptr); break; \
case 2: __get_data_asm(val, user_lh, ptr); break; \
case 4: __get_data_asm(val, user_lw, ptr); break; \
case 8: __GET_DW(val, user_ld, ptr); break; \
default: __get_user_unknown(); break; \
} \
} while (0)
#define __get_user_nocheck(x, ptr, size) \
({ \
int __gu_err; \
\
if (eva_kernel_access()) { \
__get_kernel_common((x), size, ptr); \
} else { \
__chk_user_ptr(ptr); \
__get_user_common((x), size, ptr); \
} \
__gu_err; \
})
#define __get_user_check(x, ptr, size) \
({ \
int __gu_err = -EFAULT; \
const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
\
might_fault(); \
if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) { \
if (eva_kernel_access()) \
__get_kernel_common((x), size, __gu_ptr); \
else \
__get_user_common((x), size, __gu_ptr); \
} else \
(x) = 0; \
\
__gu_err; \
})
#define __get_data_asm(val, insn, addr) \
{ \
long __gu_tmp; \
\
__asm__ __volatile__( \
"1: "insn("%1", "%3")" \n" \
"2: \n" \
" .insn \n" \
" .section .fixup,\"ax\" \n" \
"3: li %0, %4 \n" \
" move %1, $0 \n" \
" j 2b \n" \
" .previous \n" \
" .section __ex_table,\"a\" \n" \
" "__UA_ADDR "\t1b, 3b \n" \
" .previous \n" \
: "=r" (__gu_err), "=r" (__gu_tmp) \
: "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
\
(val) = (__typeof__(*(addr))) __gu_tmp; \
}
/*
* Get a long long 64 using 32 bit registers.
*/
#define __get_data_asm_ll32(val, insn, addr) \
{ \
union { \
unsigned long long l; \
__typeof__(*(addr)) t; \
} __gu_tmp; \
\
__asm__ __volatile__( \
"1: " insn("%1", "(%3)")" \n" \
"2: " insn("%D1", "4(%3)")" \n" \
"3: \n" \
" .insn \n" \
" .section .fixup,\"ax\" \n" \
"4: li %0, %4 \n" \
" move %1, $0 \n" \
" move %D1, $0 \n" \
" j 3b \n" \
" .previous \n" \
" .section __ex_table,\"a\" \n" \
" " __UA_ADDR " 1b, 4b \n" \
" " __UA_ADDR " 2b, 4b \n" \
" .previous \n" \
: "=r" (__gu_err), "=&r" (__gu_tmp.l) \
: "0" (0), "r" (addr), "i" (-EFAULT)); \
\
(val) = __gu_tmp.t; \
}
#ifndef CONFIG_EVA
#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
#else
/*
* Kernel specific functions for EVA. We need to use normal load instructions
* to read data from kernel when operating in EVA mode. We use these macros to
* avoid redefining __get_data_asm for EVA.
*/
#undef _stored
#undef _storew
#undef _storeh
#undef _storeb
#ifdef CONFIG_32BIT
#define _stored _storew
#else
#define _stored(reg, addr) "ld " reg ", " addr
#endif
#define _storew(reg, addr) "sw " reg ", " addr
#define _storeh(reg, addr) "sh " reg ", " addr
#define _storeb(reg, addr) "sb " reg ", " addr
#define __put_kernel_common(ptr, size) \
do { \
switch (size) { \
case 1: __put_data_asm(_storeb, ptr); break; \
case 2: __put_data_asm(_storeh, ptr); break; \
case 4: __put_data_asm(_storew, ptr); break; \
case 8: __PUT_DW(_stored, ptr); break; \
default: __put_user_unknown(); break; \
} \
} while(0)
#endif
/*
* Yuck. We need two variants, one for 64bit operation and one
* for 32 bit mode and old iron.
*/
#ifdef CONFIG_32BIT
#define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
#endif
#ifdef CONFIG_64BIT
#define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
#endif
#define __put_user_common(ptr, size) \
do { \
switch (size) { \
case 1: __put_data_asm(user_sb, ptr); break; \
case 2: __put_data_asm(user_sh, ptr); break; \
case 4: __put_data_asm(user_sw, ptr); break; \
case 8: __PUT_DW(user_sd, ptr); break; \
default: __put_user_unknown(); break; \
} \
} while (0)
#define __put_user_nocheck(x, ptr, size) \
({ \
__typeof__(*(ptr)) __pu_val; \
int __pu_err = 0; \
\
__pu_val = (x); \
if (eva_kernel_access()) { \
__put_kernel_common(ptr, size); \
} else { \
__chk_user_ptr(ptr); \
__put_user_common(ptr, size); \
} \
__pu_err; \
})
#define __put_user_check(x, ptr, size) \
({ \
__typeof__(*(ptr)) __user *__pu_addr = (ptr); \
__typeof__(*(ptr)) __pu_val = (x); \
int __pu_err = -EFAULT; \
\
might_fault(); \
if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
if (eva_kernel_access()) \
__put_kernel_common(__pu_addr, size); \
else \
__put_user_common(__pu_addr, size); \
} \
\
__pu_err; \
})
#define __put_data_asm(insn, ptr) \
{ \
__asm__ __volatile__( \
"1: "insn("%z2", "%3")" # __put_data_asm \n" \
"2: \n" \
" .insn \n" \
" .section .fixup,\"ax\" \n" \
"3: li %0, %4 \n" \
" j 2b \n" \
" .previous \n" \
" .section __ex_table,\"a\" \n" \
" " __UA_ADDR " 1b, 3b \n" \
" .previous \n" \
: "=r" (__pu_err) \
: "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
"i" (-EFAULT)); \
}
#define __put_data_asm_ll32(insn, ptr) \
{ \
__asm__ __volatile__( \
"1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
"2: "insn("%D2", "4(%3)")" \n" \
"3: \n" \
" .insn \n" \
" .section .fixup,\"ax\" \n" \
"4: li %0, %4 \n" \
" j 3b \n" \
" .previous \n" \
" .section __ex_table,\"a\" \n" \
" " __UA_ADDR " 1b, 4b \n" \
" " __UA_ADDR " 2b, 4b \n" \
" .previous" \
: "=r" (__pu_err) \
: "0" (0), "r" (__pu_val), "r" (ptr), \
"i" (-EFAULT)); \
}
extern void __put_user_unknown(void);
/*
* We're generating jump to subroutines which will be outside the range of
* jump instructions
*/
#ifdef MODULE
#define __MODULE_JAL(destination) \
".set\tnoat\n\t" \
__UA_LA "\t$1, " #destination "\n\t" \
"jalr\t$1\n\t" \
".set\tat\n\t"
#else
#define __MODULE_JAL(destination) \
"jal\t" #destination "\n\t"
#endif
#if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \
defined(CONFIG_CPU_HAS_PREFETCH))
#define DADDI_SCRATCH "$3"
#else
#define DADDI_SCRATCH "$0"
#endif
extern size_t __copy_user(void *__to, const void *__from, size_t __n);
#define __invoke_copy_from(func, to, from, n) \
({ \
register void *__cu_to_r __asm__("$4"); \
register const void __user *__cu_from_r __asm__("$5"); \
register long __cu_len_r __asm__("$6"); \
\
__cu_to_r = (to); \
__cu_from_r = (from); \
__cu_len_r = (n); \
__asm__ __volatile__( \
".set\tnoreorder\n\t" \
__MODULE_JAL(func) \
".set\tnoat\n\t" \
__UA_ADDU "\t$1, %1, %2\n\t" \
".set\tat\n\t" \
".set\treorder" \
: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
: \
: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
DADDI_SCRATCH, "memory"); \
__cu_len_r; \
})
#define __invoke_copy_to(func, to, from, n) \
({ \
register void __user *__cu_to_r __asm__("$4"); \
register const void *__cu_from_r __asm__("$5"); \
register long __cu_len_r __asm__("$6"); \
\
__cu_to_r = (to); \
__cu_from_r = (from); \
__cu_len_r = (n); \
__asm__ __volatile__( \
__MODULE_JAL(func) \
: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
: \
: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
DADDI_SCRATCH, "memory"); \
__cu_len_r; \
})
#define __invoke_copy_from_kernel(to, from, n) \
__invoke_copy_from(__copy_user, to, from, n)
#define __invoke_copy_to_kernel(to, from, n) \
__invoke_copy_to(__copy_user, to, from, n)
#define ___invoke_copy_in_kernel(to, from, n) \
__invoke_copy_from(__copy_user, to, from, n)
#ifndef CONFIG_EVA
#define __invoke_copy_from_user(to, from, n) \
__invoke_copy_from(__copy_user, to, from, n)
#define __invoke_copy_to_user(to, from, n) \
__invoke_copy_to(__copy_user, to, from, n)
#define ___invoke_copy_in_user(to, from, n) \
__invoke_copy_from(__copy_user, to, from, n)
#else
/* EVA specific functions */
extern size_t __copy_from_user_eva(void *__to, const void *__from,
size_t __n);
extern size_t __copy_to_user_eva(void *__to, const void *__from,
size_t __n);
extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
/*
* Source or destination address is in userland. We need to go through
* the TLB
*/
#define __invoke_copy_from_user(to, from, n) \
__invoke_copy_from(__copy_from_user_eva, to, from, n)
#define __invoke_copy_to_user(to, from, n) \
__invoke_copy_to(__copy_to_user_eva, to, from, n)
#define ___invoke_copy_in_user(to, from, n) \
__invoke_copy_from(__copy_in_user_eva, to, from, n)
#endif /* CONFIG_EVA */
static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
if (eva_kernel_access())
return __invoke_copy_to_kernel(to, from, n);
else
return __invoke_copy_to_user(to, from, n);
}
static inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
if (eva_kernel_access())
return __invoke_copy_from_kernel(to, from, n);
else
return __invoke_copy_from_user(to, from, n);
}
#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER
static inline unsigned long
raw_copy_in_user(void __user*to, const void __user *from, unsigned long n)
{
if (eva_kernel_access())
return ___invoke_copy_in_kernel(to, from, n);
else
return ___invoke_copy_in_user(to, from, n);
}
extern __kernel_size_t __bzero_kernel(void __user *addr, __kernel_size_t size);
extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size);
/*
* __clear_user: - Zero a block of memory in user space, with less checking.
* @to: Destination address, in user space.
* @n: Number of bytes to zero.
*
* Zero a block of memory in user space. Caller must check
* the specified block with access_ok() before calling this function.
*
* Returns number of bytes that could not be cleared.
* On success, this will be zero.
*/
static inline __kernel_size_t
__clear_user(void __user *addr, __kernel_size_t size)
{
__kernel_size_t res;
if (eva_kernel_access()) {
__asm__ __volatile__(
"move\t$4, %1\n\t"
"move\t$5, $0\n\t"
"move\t$6, %2\n\t"
__MODULE_JAL(__bzero_kernel)
"move\t%0, $6"
: "=r" (res)
: "r" (addr), "r" (size)
: "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
} else {
might_fault();
__asm__ __volatile__(
"move\t$4, %1\n\t"
"move\t$5, $0\n\t"
"move\t$6, %2\n\t"
__MODULE_JAL(__bzero)
"move\t%0, $6"
: "=r" (res)
: "r" (addr), "r" (size)
: "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
}
return res;
}
#define clear_user(addr,n) \
({ \
void __user * __cl_addr = (addr); \
unsigned long __cl_size = (n); \
if (__cl_size && access_ok(VERIFY_WRITE, \
__cl_addr, __cl_size)) \
__cl_size = __clear_user(__cl_addr, __cl_size); \
__cl_size; \
})
extern long __strncpy_from_kernel_asm(char *__to, const char __user *__from, long __len);
extern long __strncpy_from_user_asm(char *__to, const char __user *__from, long __len);
/*
* strncpy_from_user: - Copy a NUL terminated string from userspace.
* @dst: Destination address, in kernel space. This buffer must be at
* least @count bytes long.
* @src: Source address, in user space.
* @count: Maximum number of bytes to copy, including the trailing NUL.
*
* Copies a NUL-terminated string from userspace to kernel space.
*
* On success, returns the length of the string (not including the trailing
* NUL).
*
* If access to userspace fails, returns -EFAULT (some data may have been
* copied).
*
* If @count is smaller than the length of the string, copies @count bytes
* and returns @count.
*/
static inline long
strncpy_from_user(char *__to, const char __user *__from, long __len)
{
long res;
if (eva_kernel_access()) {
__asm__ __volatile__(
"move\t$4, %1\n\t"
"move\t$5, %2\n\t"
"move\t$6, %3\n\t"
__MODULE_JAL(__strncpy_from_kernel_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (__to), "r" (__from), "r" (__len)
: "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
} else {
might_fault();
__asm__ __volatile__(
"move\t$4, %1\n\t"
"move\t$5, %2\n\t"
"move\t$6, %3\n\t"
__MODULE_JAL(__strncpy_from_user_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (__to), "r" (__from), "r" (__len)
: "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
}
return res;
}
extern long __strnlen_kernel_asm(const char __user *s, long n);
extern long __strnlen_user_asm(const char __user *s, long n);
/*
* strnlen_user: - Get the size of a string in user space.
* @str: The string to measure.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Get the size of a NUL-terminated string in user space.
*
* Returns the size of the string INCLUDING the terminating NUL.
* On exception, returns 0.
* If the string is too long, returns a value greater than @n.
*/
static inline long strnlen_user(const char __user *s, long n)
{
long res;
might_fault();
if (eva_kernel_access()) {
__asm__ __volatile__(
"move\t$4, %1\n\t"
"move\t$5, %2\n\t"
__MODULE_JAL(__strnlen_kernel_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (s), "r" (n)
: "$2", "$4", "$5", __UA_t0, "$31");
} else {
__asm__ __volatile__(
"move\t$4, %1\n\t"
"move\t$5, %2\n\t"
__MODULE_JAL(__strnlen_user_asm)
"move\t%0, $2"
: "=r" (res)
: "r" (s), "r" (n)
: "$2", "$4", "$5", __UA_t0, "$31");
}
return res;
}
#endif /* _ASM_UACCESS_H */