Linux kernel mirror (for testing)
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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
11extern int sysctl_overcommit_memory;
12extern int sysctl_overcommit_ratio;
13extern unsigned long sysctl_overcommit_kbytes;
14extern struct percpu_counter vm_committed_as;
15
16#ifdef CONFIG_SMP
17extern s32 vm_committed_as_batch;
18#else
19#define vm_committed_as_batch 0
20#endif
21
22unsigned long vm_memory_committed(void);
23
24static inline void vm_acct_memory(long pages)
25{
26 percpu_counter_add_batch(&vm_committed_as, pages, vm_committed_as_batch);
27}
28
29static inline void vm_unacct_memory(long pages)
30{
31 vm_acct_memory(-pages);
32}
33
34/*
35 * Allow architectures to handle additional protection bits
36 */
37
38#ifndef arch_calc_vm_prot_bits
39#define arch_calc_vm_prot_bits(prot, pkey) 0
40#endif
41
42#ifndef arch_vm_get_page_prot
43#define arch_vm_get_page_prot(vm_flags) __pgprot(0)
44#endif
45
46#ifndef arch_validate_prot
47/*
48 * This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have
49 * already been masked out.
50 *
51 * Returns true if the prot flags are valid
52 */
53static inline bool arch_validate_prot(unsigned long prot)
54{
55 return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
56}
57#define arch_validate_prot arch_validate_prot
58#endif
59
60/*
61 * Optimisation macro. It is equivalent to:
62 * (x & bit1) ? bit2 : 0
63 * but this version is faster.
64 * ("bit1" and "bit2" must be single bits)
65 */
66#define _calc_vm_trans(x, bit1, bit2) \
67 ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
68 : ((x) & (bit1)) / ((bit1) / (bit2)))
69
70/*
71 * Combine the mmap "prot" argument into "vm_flags" used internally.
72 */
73static inline unsigned long
74calc_vm_prot_bits(unsigned long prot, unsigned long pkey)
75{
76 return _calc_vm_trans(prot, PROT_READ, VM_READ ) |
77 _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |
78 _calc_vm_trans(prot, PROT_EXEC, VM_EXEC) |
79 arch_calc_vm_prot_bits(prot, pkey);
80}
81
82/*
83 * Combine the mmap "flags" argument into "vm_flags" used internally.
84 */
85static inline unsigned long
86calc_vm_flag_bits(unsigned long flags)
87{
88 return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
89 _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
90 _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED );
91}
92
93unsigned long vm_commit_limit(void);
94#endif /* _LINUX_MMAN_H */