ubuntu-linux-kernel/arch/x86/include/asm/uaccess_32.h

64 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_UACCESS_32_H
#define _ASM_X86_UACCESS_32_H
/*
* User space memory access functions
*/
#include <linux/string.h>
#include <asm/asm.h>
#include <asm/page.h>
unsigned long __must_check __copy_user_ll
(void *to, const void *from, unsigned long n);
unsigned long __must_check __copy_from_user_ll_nocache_nozero
(void *to, const void __user *from, unsigned long n);
static __always_inline unsigned long __must_check
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
return __copy_user_ll((__force void *)to, from, n);
}
static __always_inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
if (__builtin_constant_p(n)) {
unsigned long ret;
switch (n) {
case 1:
ret = 0;
__uaccess_begin();
__get_user_asm_nozero(*(u8 *)to, from, ret,
"b", "b", "=q", 1);
__uaccess_end();
return ret;
case 2:
ret = 0;
__uaccess_begin();
__get_user_asm_nozero(*(u16 *)to, from, ret,
"w", "w", "=r", 2);
__uaccess_end();
return ret;
case 4:
ret = 0;
__uaccess_begin();
__get_user_asm_nozero(*(u32 *)to, from, ret,
"l", "k", "=r", 4);
__uaccess_end();
return ret;
}
}
return __copy_user_ll(to, (__force const void *)from, n);
}
static __always_inline unsigned long
__copy_from_user_inatomic_nocache(void *to, const void __user *from,
unsigned long n)
{
return __copy_from_user_ll_nocache_nozero(to, from, n);
}
#endif /* _ASM_X86_UACCESS_32_H */