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gerrit-public.fairphone.software / kernel / msm-4.19 / bf3f53089c2f51d8907398051f9a7dcf2788c4b5 / . / arch / x86 / include / asm / pkeys.h
blob: b3b09b98896d528d2ef7d425a10784e4ebe86106 [file] [log] [blame]
Dave Hansen66d37572016-02-12 13:02:32 -0800[diff] [blame]1#ifndef _ASM_X86_PKEYS_H
2#define _ASM_X86_PKEYS_H
3
Dave Hansene8c24d32016-07-29 09:30:15 -0700[diff] [blame]4#define arch_max_pkey() (boot_cpu_has(X86_FEATURE_OSPKE) ? 16 : 1)
Dave Hansen66d37572016-02-12 13:02:32 -0800[diff] [blame]5
Dave Hansen84594292016-02-12 13:02:36 -0800[diff] [blame]6extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
7 unsigned long init_val);
8
Dave Hansen62b5f7d2016-02-12 13:02:40 -0800[diff] [blame]9/*
10 * Try to dedicate one of the protection keys to be used as an
11 * execute-only protection key.
12 */
Dave Hansen62b5f7d2016-02-12 13:02:40 -0800[diff] [blame]13extern int __execute_only_pkey(struct mm_struct *mm);
14static inline int execute_only_pkey(struct mm_struct *mm)
15{
16 if (!boot_cpu_has(X86_FEATURE_OSPKE))
17 return 0;
18
19 return __execute_only_pkey(mm);
20}
21
22extern int __arch_override_mprotect_pkey(struct vm_area_struct *vma,
23 int prot, int pkey);
24static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma,
25 int prot, int pkey)
26{
27 if (!boot_cpu_has(X86_FEATURE_OSPKE))
28 return 0;
29
30 return __arch_override_mprotect_pkey(vma, prot, pkey);
31}
32
Dave Hansen7d06d9c2016-07-29 09:30:12 -0700[diff] [blame]33extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
34 unsigned long init_val);
35
Dave Hansena8502b62016-07-29 09:30:13 -0700[diff] [blame]36#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | VM_PKEY_BIT3)
37
Dave Hansene8c24d32016-07-29 09:30:15 -0700[diff] [blame]38#define mm_pkey_allocation_map(mm) (mm->context.pkey_allocation_map)
39#define mm_set_pkey_allocated(mm, pkey) do { \
40 mm_pkey_allocation_map(mm) |= (1U << pkey); \
41} while (0)
42#define mm_set_pkey_free(mm, pkey) do { \
43 mm_pkey_allocation_map(mm) &= ~(1U << pkey); \
44} while (0)
45
46static inline
47bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
48{
Dave Hansen58ab9a02017-02-23 14:26:03 -0800[diff] [blame]49 /*
50 * "Allocated" pkeys are those that have been returned
51 * from pkey_alloc(). pkey 0 is special, and never
52 * returned from pkey_alloc().
53 */
54 if (pkey <= 0)
55 return false;
56 if (pkey >= arch_max_pkey())
57 return false;
Dave Hansene8c24d32016-07-29 09:30:15 -0700[diff] [blame]58 return mm_pkey_allocation_map(mm) & (1U << pkey);
59}
60
61/*
62 * Returns a positive, 4-bit key on success, or -1 on failure.
63 */
64static inline
65int mm_pkey_alloc(struct mm_struct *mm)
66{
67 /*
68 * Note: this is the one and only place we make sure
69 * that the pkey is valid as far as the hardware is
70 * concerned. The rest of the kernel trusts that
71 * only good, valid pkeys come out of here.
72 */
73 u16 all_pkeys_mask = ((1U << arch_max_pkey()) - 1);
74 int ret;
75
76 /*
77 * Are we out of pkeys? We must handle this specially
78 * because ffz() behavior is undefined if there are no
79 * zeros.
80 */
81 if (mm_pkey_allocation_map(mm) == all_pkeys_mask)
82 return -1;
83
84 ret = ffz(mm_pkey_allocation_map(mm));
85
86 mm_set_pkey_allocated(mm, ret);
87
88 return ret;
89}
90
91static inline
92int mm_pkey_free(struct mm_struct *mm, int pkey)
93{
Dave Hansene8c24d32016-07-29 09:30:15 -0700[diff] [blame]94 if (!mm_pkey_is_allocated(mm, pkey))
95 return -EINVAL;
96
97 mm_set_pkey_free(mm, pkey);
98
99 return 0;
100}
101
102extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
103 unsigned long init_val);
104extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
105 unsigned long init_val);
Dave Hansenacd547b2016-07-29 09:30:21 -0700[diff] [blame]106extern void copy_init_pkru_to_fpregs(void);
Dave Hansene8c24d32016-07-29 09:30:15 -0700[diff] [blame]107
Dave Hansen66d37572016-02-12 13:02:32 -0800[diff] [blame]108#endif /*_ASM_X86_PKEYS_H */