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 16 extern int sysctl_overcommit_memory; 17 extern int sysctl_overcommit_ratio; 18 extern atomic_t vm_committed_space; 19 20 #ifdef CONFIG_SMP 21 extern void vm_acct_memory(long pages); 22 #else 23 static inline void vm_acct_memory(long pages) 24 { 25 atomic_add(pages, &vm_committed_space); 26 } 27 #endif 28 29 static 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 */ 47 static inline unsigned long 48 calc_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 */ 58 static inline unsigned long 59 calc_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 */ 68