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