Linux kernel mirror (for testing)
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1#ifndef _LINUX_MMAN_H
2#define _LINUX_MMAN_H
3
4#include <linux/mm.h>
5#include <linux/percpu_counter.h>
6
7#include <linux/atomic.h>
8#include <uapi/linux/mman.h>
9
10extern int sysctl_overcommit_memory;
11extern int sysctl_overcommit_ratio;
12extern struct percpu_counter vm_committed_as;
13
14unsigned long vm_memory_committed(void);
15
16static inline void vm_acct_memory(long pages)
17{
18 percpu_counter_add(&vm_committed_as, pages);
19}
20
21static inline void vm_unacct_memory(long pages)
22{
23 vm_acct_memory(-pages);
24}
25
26/*
27 * Allow architectures to handle additional protection bits
28 */
29
30#ifndef arch_calc_vm_prot_bits
31#define arch_calc_vm_prot_bits(prot) 0
32#endif
33
34#ifndef arch_vm_get_page_prot
35#define arch_vm_get_page_prot(vm_flags) __pgprot(0)
36#endif
37
38#ifndef arch_validate_prot
39/*
40 * This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have
41 * already been masked out.
42 *
43 * Returns true if the prot flags are valid
44 */
45static inline int arch_validate_prot(unsigned long prot)
46{
47 return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
48}
49#define arch_validate_prot arch_validate_prot
50#endif
51
52/*
53 * Optimisation macro. It is equivalent to:
54 * (x & bit1) ? bit2 : 0
55 * but this version is faster.
56 * ("bit1" and "bit2" must be single bits)
57 */
58#define _calc_vm_trans(x, bit1, bit2) \
59 ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
60 : ((x) & (bit1)) / ((bit1) / (bit2)))
61
62/*
63 * Combine the mmap "prot" argument into "vm_flags" used internally.
64 */
65static inline unsigned long
66calc_vm_prot_bits(unsigned long prot)
67{
68 return _calc_vm_trans(prot, PROT_READ, VM_READ ) |
69 _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |
70 _calc_vm_trans(prot, PROT_EXEC, VM_EXEC) |
71 arch_calc_vm_prot_bits(prot);
72}
73
74/*
75 * Combine the mmap "flags" argument into "vm_flags" used internally.
76 */
77static inline unsigned long
78calc_vm_flag_bits(unsigned long flags)
79{
80 return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
81 _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
82 _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED );
83}
84#endif /* _LINUX_MMAN_H */