arch/riscv/include/asm/kasan.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /* Copyright (C) 2019 Andes Technology Corporation */
   3
   4 #ifndef __ASM_KASAN_H
   5 #define __ASM_KASAN_H
   6
   7 #ifndef __ASSEMBLY__
   8
   9 /*
  10  * The following comment was copied from arm64:
  11  * KASAN_SHADOW_START: beginning of the kernel virtual addresses.
  12  * KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses,
  13  * where N = (1 << KASAN_SHADOW_SCALE_SHIFT).
  14  *
  15  * KASAN_SHADOW_OFFSET:
  16  * This value is used to map an address to the corresponding shadow
  17  * address by the following formula:
  18  *     shadow_addr = (address >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET
  19  *
  20  * (1 << (64 - KASAN_SHADOW_SCALE_SHIFT)) shadow addresses that lie in range
  21  * [KASAN_SHADOW_OFFSET, KASAN_SHADOW_END) cover all 64-bits of virtual
  22  * addresses. So KASAN_SHADOW_OFFSET should satisfy the following equation:
  23  *      KASAN_SHADOW_OFFSET = KASAN_SHADOW_END -
  24  *                              (1ULL << (64 - KASAN_SHADOW_SCALE_SHIFT))
  25  */
  26 #define KASAN_SHADOW_SCALE_SHIFT        3
  27
  28 #define KASAN_SHADOW_SIZE       (UL(1) << ((VA_BITS - 1) - KASAN_SHADOW_SCALE_SHIFT))
  29 /*
  30  * Depending on the size of the virtual address space, the region may not be
  31  * aligned on PGDIR_SIZE, so force its alignment to ease its population.
  32  */
  33 #define KASAN_SHADOW_START      ((KASAN_SHADOW_END - KASAN_SHADOW_SIZE) & PGDIR_MASK)
  34 #define KASAN_SHADOW_END        MODULES_LOWEST_VADDR
  35
  36 #ifdef CONFIG_KASAN
  37 #define KASAN_SHADOW_OFFSET     _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
  38
  39 void kasan_init(void);
  40 asmlinkage void kasan_early_init(void);
  41 void kasan_swapper_init(void);
  42
  43 #endif
  44 #endif
  45 #endif /* __ASM_KASAN_H */