linux/arch/arm64/include/asm/kasan.h
Steve Capper 5383cc6efe arm64: mm: Introduce vabits_actual
In order to support 52-bit kernel addresses detectable at boot time, one
needs to know the actual VA_BITS detected. A new variable vabits_actual
is introduced in this commit and employed for the KVM hypervisor layout,
KASAN, fault handling and phys-to/from-virt translation where there
would normally be compile time constants.

In order to maintain performance in phys_to_virt, another variable
physvirt_offset is introduced.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09 11:17:21 +01:00

47 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_KASAN_H
#define __ASM_KASAN_H
#ifndef __ASSEMBLY__
#include <linux/linkage.h>
#include <asm/memory.h>
#include <asm/pgtable-types.h>
#define arch_kasan_set_tag(addr, tag) __tag_set(addr, tag)
#define arch_kasan_reset_tag(addr) __tag_reset(addr)
#define arch_kasan_get_tag(addr) __tag_get(addr)
#ifdef CONFIG_KASAN
/*
* KASAN_SHADOW_START: beginning of the kernel virtual addresses.
* KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses,
* where N = (1 << KASAN_SHADOW_SCALE_SHIFT).
*
* KASAN_SHADOW_OFFSET:
* This value is used to map an address to the corresponding shadow
* address by the following formula:
* shadow_addr = (address >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET
*
* (1 << (64 - KASAN_SHADOW_SCALE_SHIFT)) shadow addresses that lie in range
* [KASAN_SHADOW_OFFSET, KASAN_SHADOW_END) cover all 64-bits of virtual
* addresses. So KASAN_SHADOW_OFFSET should satisfy the following equation:
* KASAN_SHADOW_OFFSET = KASAN_SHADOW_END -
* (1ULL << (64 - KASAN_SHADOW_SCALE_SHIFT))
*/
#define _KASAN_SHADOW_START(va) (KASAN_SHADOW_END - (1UL << ((va) - KASAN_SHADOW_SCALE_SHIFT)))
#define KASAN_SHADOW_START _KASAN_SHADOW_START(vabits_actual)
void kasan_init(void);
void kasan_copy_shadow(pgd_t *pgdir);
asmlinkage void kasan_early_init(void);
#else
static inline void kasan_init(void) { }
static inline void kasan_copy_shadow(pgd_t *pgdir) { }
#endif
#endif
#endif