1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_KASAN_H
3#define __ASM_KASAN_H
4
5#ifndef __ASSEMBLY__
6
7#include <linux/linkage.h>
8#include <asm/memory.h>
9#include <asm/pgtable-types.h>
10
11#define arch_kasan_set_tag(addr, tag)	__tag_set(addr, tag)
12#define arch_kasan_reset_tag(addr)	__tag_reset(addr)
13#define arch_kasan_get_tag(addr)	__tag_get(addr)
14
15#ifdef CONFIG_KASAN
16
17/*
18 * KASAN_SHADOW_START: beginning of the kernel virtual addresses.
19 * KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses,
20 * where N = (1 << KASAN_SHADOW_SCALE_SHIFT).
21 *
22 * KASAN_SHADOW_OFFSET:
23 * This value is used to map an address to the corresponding shadow
24 * address by the following formula:
25 *     shadow_addr = (address >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET
26 *
27 * (1 << (64 - KASAN_SHADOW_SCALE_SHIFT)) shadow addresses that lie in range
28 * [KASAN_SHADOW_OFFSET, KASAN_SHADOW_END) cover all 64-bits of virtual
29 * addresses. So KASAN_SHADOW_OFFSET should satisfy the following equation:
30 *      KASAN_SHADOW_OFFSET = KASAN_SHADOW_END -
31 *				(1ULL << (64 - KASAN_SHADOW_SCALE_SHIFT))
32 */
33#define _KASAN_SHADOW_START(va)	(KASAN_SHADOW_END - (1UL << ((va) - KASAN_SHADOW_SCALE_SHIFT)))
34#define KASAN_SHADOW_START      _KASAN_SHADOW_START(vabits_actual)
35
36void kasan_init(void);
37void kasan_copy_shadow(pgd_t *pgdir);
38asmlinkage void kasan_early_init(void);
39
40#else
41static inline void kasan_init(void) { }
42static inline void kasan_copy_shadow(pgd_t *pgdir) { }
43#endif
44
45#endif
46#endif
47