1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _LINUX_MMAN_H |
3 | #define _LINUX_MMAN_H |
4 | |
5 | #include <linux/mm.h> |
6 | #include <linux/percpu_counter.h> |
7 | |
8 | #include <linux/atomic.h> |
9 | #include <uapi/linux/mman.h> |
10 | |
11 | /* |
12 | * Arrange for legacy / undefined architecture specific flags to be |
13 | * ignored by mmap handling code. |
14 | */ |
15 | #ifndef MAP_32BIT |
16 | #define MAP_32BIT 0 |
17 | #endif |
18 | #ifndef MAP_HUGE_2MB |
19 | #define MAP_HUGE_2MB 0 |
20 | #endif |
21 | #ifndef MAP_HUGE_1GB |
22 | #define MAP_HUGE_1GB 0 |
23 | #endif |
24 | #ifndef MAP_UNINITIALIZED |
25 | #define MAP_UNINITIALIZED 0 |
26 | #endif |
27 | #ifndef MAP_SYNC |
28 | #define MAP_SYNC 0 |
29 | #endif |
30 | |
31 | /* |
32 | * The historical set of flags that all mmap implementations implicitly |
33 | * support when a ->mmap_validate() op is not provided in file_operations. |
34 | */ |
35 | #define LEGACY_MAP_MASK (MAP_SHARED \ |
36 | | MAP_PRIVATE \ |
37 | | MAP_FIXED \ |
38 | | MAP_ANONYMOUS \ |
39 | | MAP_DENYWRITE \ |
40 | | MAP_EXECUTABLE \ |
41 | | MAP_UNINITIALIZED \ |
42 | | MAP_GROWSDOWN \ |
43 | | MAP_LOCKED \ |
44 | | MAP_NORESERVE \ |
45 | | MAP_POPULATE \ |
46 | | MAP_NONBLOCK \ |
47 | | MAP_STACK \ |
48 | | MAP_HUGETLB \ |
49 | | MAP_32BIT \ |
50 | | MAP_HUGE_2MB \ |
51 | | MAP_HUGE_1GB) |
52 | |
53 | extern int sysctl_overcommit_memory; |
54 | extern int sysctl_overcommit_ratio; |
55 | extern unsigned long sysctl_overcommit_kbytes; |
56 | extern struct percpu_counter vm_committed_as; |
57 | |
58 | #ifdef CONFIG_SMP |
59 | extern s32 vm_committed_as_batch; |
60 | #else |
61 | #define vm_committed_as_batch 0 |
62 | #endif |
63 | |
64 | unsigned long vm_memory_committed(void); |
65 | |
66 | static inline void vm_acct_memory(long pages) |
67 | { |
68 | percpu_counter_add_batch(&vm_committed_as, pages, vm_committed_as_batch); |
69 | } |
70 | |
71 | static inline void vm_unacct_memory(long pages) |
72 | { |
73 | vm_acct_memory(-pages); |
74 | } |
75 | |
76 | /* |
77 | * Allow architectures to handle additional protection bits |
78 | */ |
79 | |
80 | #ifndef arch_calc_vm_prot_bits |
81 | #define arch_calc_vm_prot_bits(prot, pkey) 0 |
82 | #endif |
83 | |
84 | #ifndef arch_vm_get_page_prot |
85 | #define arch_vm_get_page_prot(vm_flags) __pgprot(0) |
86 | #endif |
87 | |
88 | #ifndef arch_validate_prot |
89 | /* |
90 | * This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have |
91 | * already been masked out. |
92 | * |
93 | * Returns true if the prot flags are valid |
94 | */ |
95 | static inline bool arch_validate_prot(unsigned long prot, unsigned long addr) |
96 | { |
97 | return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0; |
98 | } |
99 | #define arch_validate_prot arch_validate_prot |
100 | #endif |
101 | |
102 | /* |
103 | * Optimisation macro. It is equivalent to: |
104 | * (x & bit1) ? bit2 : 0 |
105 | * but this version is faster. |
106 | * ("bit1" and "bit2" must be single bits) |
107 | */ |
108 | #define _calc_vm_trans(x, bit1, bit2) \ |
109 | ((!(bit1) || !(bit2)) ? 0 : \ |
110 | ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \ |
111 | : ((x) & (bit1)) / ((bit1) / (bit2)))) |
112 | |
113 | /* |
114 | * Combine the mmap "prot" argument into "vm_flags" used internally. |
115 | */ |
116 | static inline unsigned long |
117 | calc_vm_prot_bits(unsigned long prot, unsigned long pkey) |
118 | { |
119 | return _calc_vm_trans(prot, PROT_READ, VM_READ ) | |
120 | _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) | |
121 | _calc_vm_trans(prot, PROT_EXEC, VM_EXEC) | |
122 | arch_calc_vm_prot_bits(prot, pkey); |
123 | } |
124 | |
125 | /* |
126 | * Combine the mmap "flags" argument into "vm_flags" used internally. |
127 | */ |
128 | static inline unsigned long |
129 | calc_vm_flag_bits(unsigned long flags) |
130 | { |
131 | return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) | |
132 | _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) | |
133 | _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ) | |
134 | _calc_vm_trans(flags, MAP_SYNC, VM_SYNC ); |
135 | } |
136 | |
137 | unsigned long vm_commit_limit(void); |
138 | #endif /* _LINUX_MMAN_H */ |
139 | |