1 | // SPDX-License-Identifier: GPL-2.0 |
2 | |
3 | #include <linux/export.h> |
4 | #include <linux/mm.h> |
5 | #include <asm/pgtable.h> |
6 | #include <asm/mem_encrypt.h> |
7 | |
8 | static pgprot_t protection_map[16] __ro_after_init = { |
9 | [VM_NONE] = PAGE_NONE, |
10 | [VM_READ] = PAGE_READONLY, |
11 | [VM_WRITE] = PAGE_COPY, |
12 | [VM_WRITE | VM_READ] = PAGE_COPY, |
13 | [VM_EXEC] = PAGE_READONLY_EXEC, |
14 | [VM_EXEC | VM_READ] = PAGE_READONLY_EXEC, |
15 | [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC, |
16 | [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC, |
17 | [VM_SHARED] = PAGE_NONE, |
18 | [VM_SHARED | VM_READ] = PAGE_READONLY, |
19 | [VM_SHARED | VM_WRITE] = PAGE_SHARED, |
20 | [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED, |
21 | [VM_SHARED | VM_EXEC] = PAGE_READONLY_EXEC, |
22 | [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY_EXEC, |
23 | [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC, |
24 | [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC |
25 | }; |
26 | |
27 | void add_encrypt_protection_map(void) |
28 | { |
29 | unsigned int i; |
30 | |
31 | for (i = 0; i < ARRAY_SIZE(protection_map); i++) |
32 | protection_map[i] = pgprot_encrypted(protection_map[i]); |
33 | } |
34 | |
35 | pgprot_t vm_get_page_prot(unsigned long vm_flags) |
36 | { |
37 | unsigned long val = pgprot_val(protection_map[vm_flags & |
38 | (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]); |
39 | |
40 | #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS |
41 | /* |
42 | * Take the 4 protection key bits out of the vma->vm_flags value and |
43 | * turn them in to the bits that we can put in to a pte. |
44 | * |
45 | * Only override these if Protection Keys are available (which is only |
46 | * on 64-bit). |
47 | */ |
48 | if (vm_flags & VM_PKEY_BIT0) |
49 | val |= _PAGE_PKEY_BIT0; |
50 | if (vm_flags & VM_PKEY_BIT1) |
51 | val |= _PAGE_PKEY_BIT1; |
52 | if (vm_flags & VM_PKEY_BIT2) |
53 | val |= _PAGE_PKEY_BIT2; |
54 | if (vm_flags & VM_PKEY_BIT3) |
55 | val |= _PAGE_PKEY_BIT3; |
56 | #endif |
57 | |
58 | val = __sme_set(val); |
59 | if (val & _PAGE_PRESENT) |
60 | val &= __supported_pte_mask; |
61 | return __pgprot(val); |
62 | } |
63 | EXPORT_SYMBOL(vm_get_page_prot); |
64 | |