tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2016 ARM Ltd.
4 */
5#ifndef __ASM_PGTABLE_PROT_H
6#define __ASM_PGTABLE_PROT_H
7
8#include <asm/memory.h>
9#include <asm/pgtable-hwdef.h>
10
11#include <linux/const.h>
12
13/*
14 * Software defined PTE bits definition.
15 */
16#define PTE_WRITE (PTE_DBM) /* same as DBM (51) */
17#define PTE_SWP_EXCLUSIVE (_AT(pteval_t, 1) << 2) /* only for swp ptes */
18#define PTE_DIRTY (_AT(pteval_t, 1) << 55)
19#define PTE_SPECIAL (_AT(pteval_t, 1) << 56)
20#define PTE_DEVMAP (_AT(pteval_t, 1) << 57)
21#define PTE_PROT_NONE (_AT(pteval_t, 1) << 58) /* only when !PTE_VALID */
22
23/*
24 * This bit indicates that the entry is present i.e. pmd_page()
25 * still points to a valid huge page in memory even if the pmd
26 * has been invalidated.
27 */
28#define PMD_PRESENT_INVALID (_AT(pteval_t, 1) << 59) /* only when !PMD_SECT_VALID */
29
30#ifndef __ASSEMBLY__
31
32#include <asm/cpufeature.h>
33#include <asm/pgtable-types.h>
34
35extern bool arm64_use_ng_mappings;
36
37#define _PROT_DEFAULT (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
38#define _PROT_SECT_DEFAULT (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
39
40#define PTE_MAYBE_NG (arm64_use_ng_mappings ? PTE_NG : 0)
41#define PMD_MAYBE_NG (arm64_use_ng_mappings ? PMD_SECT_NG : 0)
42
43/*
44 * If we have userspace only BTI we don't want to mark kernel pages
45 * guarded even if the system does support BTI.
46 */
47#ifdef CONFIG_ARM64_BTI_KERNEL
48#define PTE_MAYBE_GP (system_supports_bti() ? PTE_GP : 0)
49#else
50#define PTE_MAYBE_GP 0
51#endif
52
53#define PROT_DEFAULT (_PROT_DEFAULT | PTE_MAYBE_NG)
54#define PROT_SECT_DEFAULT (_PROT_SECT_DEFAULT | PMD_MAYBE_NG)
55
56#define PROT_DEVICE_nGnRnE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRnE))
57#define PROT_DEVICE_nGnRE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRE))
58#define PROT_NORMAL_NC (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_NC))
59#define PROT_NORMAL (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL))
60#define PROT_NORMAL_TAGGED (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_TAGGED))
61
62#define PROT_SECT_DEVICE_nGnRE (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE))
63#define PROT_SECT_NORMAL (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
64#define PROT_SECT_NORMAL_EXEC (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
65
66#define _PAGE_DEFAULT (_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL))
67
68#define PAGE_KERNEL __pgprot(PROT_NORMAL)
69#define PAGE_KERNEL_RO __pgprot((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY)
70#define PAGE_KERNEL_ROX __pgprot((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY)
71#define PAGE_KERNEL_EXEC __pgprot(PROT_NORMAL & ~PTE_PXN)
72#define PAGE_KERNEL_EXEC_CONT __pgprot((PROT_NORMAL & ~PTE_PXN) | PTE_CONT)
73
74#define PAGE_S2_MEMATTR(attr, has_fwb) \
75 ({ \
76 u64 __val; \
77 if (has_fwb) \
78 __val = PTE_S2_MEMATTR(MT_S2_FWB_ ## attr); \
79 else \
80 __val = PTE_S2_MEMATTR(MT_S2_ ## attr); \
81 __val; \
82 })
83
84#define PAGE_NONE __pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN)
85/* shared+writable pages are clean by default, hence PTE_RDONLY|PTE_WRITE */
86#define PAGE_SHARED __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE)
87#define PAGE_SHARED_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_WRITE)
88#define PAGE_READONLY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN)
89#define PAGE_READONLY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN)
90#define PAGE_EXECONLY __pgprot(_PAGE_DEFAULT | PTE_RDONLY | PTE_NG | PTE_PXN)
91
92#endif /* __ASSEMBLY__ */
93
94#endif /* __ASM_PGTABLE_PROT_H */