arch/riscv/include/asm/pgtable-bits.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2012 Regents of the University of California
   4  */
   5
   6 #ifndef _ASM_RISCV_PGTABLE_BITS_H
   7 #define _ASM_RISCV_PGTABLE_BITS_H
   8
   9 /*
  10  * PTE format:
  11  * | XLEN-1  10 | 9             8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
  12  *       PFN      reserved for SW   D   A   G   U   X   W   R   V
  13  */
  14
  15 #define _PAGE_ACCESSED_OFFSET 6
  16
  17 #define _PAGE_PRESENT   (1 << 0)
  18 #define _PAGE_READ      (1 << 1)    /* Readable */
  19 #define _PAGE_WRITE     (1 << 2)    /* Writable */
  20 #define _PAGE_EXEC      (1 << 3)    /* Executable */
  21 #define _PAGE_USER      (1 << 4)    /* User */
  22 #define _PAGE_GLOBAL    (1 << 5)    /* Global */
  23 #define _PAGE_ACCESSED  (1 << 6)    /* Set by hardware on any access */
  24 #define _PAGE_DIRTY     (1 << 7)    /* Set by hardware on any write */
  25 #define _PAGE_SOFT      (1 << 8)    /* Reserved for software */
  26
  27 #define _PAGE_SPECIAL   _PAGE_SOFT
  28 #define _PAGE_TABLE     _PAGE_PRESENT
  29
  30 /*
  31  * _PAGE_PROT_NONE is set on not-present pages (and ignored by the hardware) to
  32  * distinguish them from swapped out pages
  33  */
  34 #define _PAGE_PROT_NONE _PAGE_READ
  35
  36 #define _PAGE_PFN_SHIFT 10
  37
  38 /* Set of bits to preserve across pte_modify() */
  39 #define _PAGE_CHG_MASK  (~(unsigned long)(_PAGE_PRESENT | _PAGE_READ |  \
  40                                           _PAGE_WRITE | _PAGE_EXEC |    \
  41                                           _PAGE_USER | _PAGE_GLOBAL))
  42
  43 #endif /* _ASM_RISCV_PGTABLE_BITS_H */