Linux kernel mirror (for testing)
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linux
1#ifndef _LINUX_MMAN_H
2#define _LINUX_MMAN_H
3
4#include <linux/config.h>
5#include <linux/mm.h>
6
7#include <asm/atomic.h>
8#include <asm/mman.h>
9
10#define MREMAP_MAYMOVE 1
11#define MREMAP_FIXED 2
12
13#define OVERCOMMIT_GUESS 0
14#define OVERCOMMIT_ALWAYS 1
15#define OVERCOMMIT_NEVER 2
16extern int sysctl_overcommit_memory;
17extern int sysctl_overcommit_ratio;
18extern atomic_t vm_committed_space;
19
20#ifdef CONFIG_SMP
21extern void vm_acct_memory(long pages);
22#else
23static inline void vm_acct_memory(long pages)
24{
25 atomic_add(pages, &vm_committed_space);
26}
27#endif
28
29static inline void vm_unacct_memory(long pages)
30{
31 vm_acct_memory(-pages);
32}
33
34/*
35 * Optimisation macro. It is equivalent to:
36 * (x & bit1) ? bit2 : 0
37 * but this version is faster.
38 * ("bit1" and "bit2" must be single bits)
39 */
40#define _calc_vm_trans(x, bit1, bit2) \
41 ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
42 : ((x) & (bit1)) / ((bit1) / (bit2)))
43
44/*
45 * Combine the mmap "prot" argument into "vm_flags" used internally.
46 */
47static inline unsigned long
48calc_vm_prot_bits(unsigned long prot)
49{
50 return _calc_vm_trans(prot, PROT_READ, VM_READ ) |
51 _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |
52 _calc_vm_trans(prot, PROT_EXEC, VM_EXEC );
53}
54
55/*
56 * Combine the mmap "flags" argument into "vm_flags" used internally.
57 */
58static inline unsigned long
59calc_vm_flag_bits(unsigned long flags)
60{
61 return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
62 _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
63 _calc_vm_trans(flags, MAP_EXECUTABLE, VM_EXECUTABLE) |
64 _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED );
65}
66
67#endif /* _LINUX_MMAN_H */