Linux 2.6.33-rc2
[pohmelfs.git] / include / linux / mman.h
blob9872d6ca58ae9a7b88dcc97387f86a434a633db5
1 #ifndef _LINUX_MMAN_H
2 #define _LINUX_MMAN_H
4 #include <asm/mman.h>
6 #define MREMAP_MAYMOVE 1
7 #define MREMAP_FIXED 2
9 #define OVERCOMMIT_GUESS 0
10 #define OVERCOMMIT_ALWAYS 1
11 #define OVERCOMMIT_NEVER 2
13 #ifdef __KERNEL__
14 #include <linux/mm.h>
15 #include <linux/percpu_counter.h>
17 #include <asm/atomic.h>
19 extern int sysctl_overcommit_memory;
20 extern int sysctl_overcommit_ratio;
21 extern struct percpu_counter vm_committed_as;
23 static inline void vm_acct_memory(long pages)
25 percpu_counter_add(&vm_committed_as, pages);
28 static inline void vm_unacct_memory(long pages)
30 vm_acct_memory(-pages);
34 * Allow architectures to handle additional protection bits
37 #ifndef arch_calc_vm_prot_bits
38 #define arch_calc_vm_prot_bits(prot) 0
39 #endif
41 #ifndef arch_vm_get_page_prot
42 #define arch_vm_get_page_prot(vm_flags) __pgprot(0)
43 #endif
45 #ifndef arch_validate_prot
47 * This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have
48 * already been masked out.
50 * Returns true if the prot flags are valid
52 static inline int arch_validate_prot(unsigned long prot)
54 return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
56 #define arch_validate_prot arch_validate_prot
57 #endif
60 * Optimisation macro. It is equivalent to:
61 * (x & bit1) ? bit2 : 0
62 * but this version is faster.
63 * ("bit1" and "bit2" must be single bits)
65 #define _calc_vm_trans(x, bit1, bit2) \
66 ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
67 : ((x) & (bit1)) / ((bit1) / (bit2)))
70 * Combine the mmap "prot" argument into "vm_flags" used internally.
72 static inline unsigned long
73 calc_vm_prot_bits(unsigned long prot)
75 return _calc_vm_trans(prot, PROT_READ, VM_READ ) |
76 _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |
77 _calc_vm_trans(prot, PROT_EXEC, VM_EXEC) |
78 arch_calc_vm_prot_bits(prot);
82 * Combine the mmap "flags" argument into "vm_flags" used internally.
84 static inline unsigned long
85 calc_vm_flag_bits(unsigned long flags)
87 return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
88 _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
89 _calc_vm_trans(flags, MAP_EXECUTABLE, VM_EXECUTABLE) |
90 _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED );
92 #endif /* __KERNEL__ */
93 #endif /* _LINUX_MMAN_H */