1 #ifndef _LINUX_MMAN_H 2 #define _LINUX_MMAN_H 3 4 #include <asm/mman.h> 5 6 #define MREMAP_MAYMOVE 1 7 #define MREMAP_FIXED 2 8 9 #define OVERCOMMIT_GUESS 0 10 #define OVERCOMMIT_ALWAYS 1 11 #define OVERCOMMIT_NEVER 2 12 13 #ifdef __KERNEL__ 14 #include <linux/mm.h> 15 16 #include <asm/atomic.h> 17 18 extern int sysctl_overcommit_memory; 19 extern int sysctl_overcommit_ratio; 20 extern atomic_t vm_committed_space; 21 22 #ifdef CONFIG_SMP 23 extern void vm_acct_memory(long pages); 24 #else 25 static inline void vm_acct_memory(long pages) 26 { 27 atomic_add(pages, &vm_committed_space); 28 } 29 #endif 30 31 static inline void vm_unacct_memory(long pages) 32 { 33 vm_acct_memory(-pages); 34 } 35 36 /* 37 * Optimisation macro. It is equivalent to: 38 * (x & bit1) ? bit2 : 0 39 * but this version is faster. 40 * ("bit1" and "bit2" must be single bits) 41 */ 42 #define _calc_vm_trans(x, bit1, bit2) \ 43 ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \ 44 : ((x) & (bit1)) / ((bit1) / (bit2))) 45 46 /* 47 * Combine the mmap "prot" argument into "vm_flags" used internally. 48 */ 49 static inline unsigned long 50 calc_vm_prot_bits(unsigned long prot) 51 { 52 return _calc_vm_trans(prot, PROT_READ, VM_READ ) | 53 _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) | 54 _calc_vm_trans(prot, PROT_EXEC, VM_EXEC ); 55 } 56 57 /* 58 * Combine the mmap "flags" argument into "vm_flags" used internally. 59 */ 60 static inline unsigned long 61 calc_vm_flag_bits(unsigned long flags) 62 { 63 return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) | 64 _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) | 65 _calc_vm_trans(flags, MAP_EXECUTABLE, VM_EXECUTABLE) | 66 _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ); 67 } 68 #endif /* __KERNEL__ */ 69 #endif /* _LINUX_MMAN_H */ 70