kernel/arch/hexagon/include/asm/uaccess.h
2024-07-22 17:22:30 +08:00

64 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* User memory access support for Hexagon
*
* Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
*/
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H
/*
* User space memory access functions
*/
#include <asm/sections.h>
/*
* access_ok: - Checks if a user space pointer is valid
* @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.
*
*/
#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg)
#define user_addr_max() (uaccess_kernel() ? ~0UL : TASK_SIZE)
static inline int __access_ok(unsigned long addr, unsigned long size)
{
unsigned long limit = TASK_SIZE;
return (size <= limit) && (addr <= (limit - size));
}
#define __access_ok __access_ok
/*
* When a kernel-mode page fault is taken, the faulting instruction
* address is checked against a table of exception_table_entries.
* Each entry is a tuple of the address of an instruction that may
* be authorized to fault, and the address at which execution should
* be resumed instead of the faulting instruction, so as to effect
* a workaround.
*/
/* Assembly somewhat optimized copy routines */
unsigned long raw_copy_from_user(void *to, const void __user *from,
unsigned long n);
unsigned long raw_copy_to_user(void __user *to, const void *from,
unsigned long n);
#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER
__kernel_size_t __clear_user_hexagon(void __user *dest, unsigned long count);
#define __clear_user(a, s) __clear_user_hexagon((a), (s))
#include <asm-generic/uaccess.h>
#endif