xref: /linux/arch/riscv/include/asm/pgtable-bits.h (revision 7203ca412fc8e8a0588e9adc0f777d3163f8dff3)
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 #define _PAGE_ACCESSED_OFFSET 6
10 
11 #define _PAGE_PRESENT   (1 << 0)
12 #define _PAGE_READ      (1 << 1)    /* Readable */
13 #define _PAGE_WRITE     (1 << 2)    /* Writable */
14 #define _PAGE_EXEC      (1 << 3)    /* Executable */
15 #define _PAGE_USER      (1 << 4)    /* User */
16 #define _PAGE_GLOBAL    (1 << 5)    /* Global */
17 #define _PAGE_ACCESSED  (1 << 6)    /* Set by hardware on any access */
18 #define _PAGE_DIRTY     (1 << 7)    /* Set by hardware on any write */
19 #define _PAGE_SOFT      (3 << 8)    /* Reserved for software */
20 
21 #define _PAGE_SPECIAL   (1 << 8)    /* RSW: 0x1 */
22 
23 #ifdef CONFIG_MEM_SOFT_DIRTY
24 
25 /* ext_svrsw60t59b: bit 59 for soft-dirty tracking */
26 #define _PAGE_SOFT_DIRTY						\
27 	((riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B)) ?	\
28 	 (1UL << 59) : 0)
29 /*
30  * Bit 3 is always zero for swap entry computation, so we
31  * can borrow it for swap page soft-dirty tracking.
32  */
33 #define _PAGE_SWP_SOFT_DIRTY						\
34 	((riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B)) ?	\
35 	 _PAGE_EXEC : 0)
36 #else
37 #define _PAGE_SOFT_DIRTY	0
38 #define _PAGE_SWP_SOFT_DIRTY	0
39 #endif /* CONFIG_MEM_SOFT_DIRTY */
40 
41 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
42 
43 /* ext_svrsw60t59b: Bit(60) for uffd-wp tracking */
44 #define _PAGE_UFFD_WP							\
45 	((riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B)) ?	\
46 	 (1UL << 60) : 0)
47 /*
48  * Bit 4 is not involved into swap entry computation, so we
49  * can borrow it for swap page uffd-wp tracking.
50  */
51 #define _PAGE_SWP_UFFD_WP						\
52 	((riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B)) ?	\
53 	 _PAGE_USER : 0)
54 #else
55 #define _PAGE_UFFD_WP		0
56 #define _PAGE_SWP_UFFD_WP	0
57 #endif
58 
59 #define _PAGE_TABLE     _PAGE_PRESENT
60 
61 /*
62  * _PAGE_PROT_NONE is set on not-present pages (and ignored by the hardware) to
63  * distinguish them from swapped out pages
64  */
65 #define _PAGE_PROT_NONE _PAGE_GLOBAL
66 
67 /* Used for swap PTEs only. */
68 #define _PAGE_SWP_EXCLUSIVE _PAGE_ACCESSED
69 
70 #define _PAGE_PFN_SHIFT 10
71 
72 /*
73  * when all of R/W/X are zero, the PTE is a pointer to the next level
74  * of the page table; otherwise, it is a leaf PTE.
75  */
76 #define _PAGE_LEAF (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
77 
78 #endif /* _ASM_RISCV_PGTABLE_BITS_H */
79