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 10 extern int sysctl_overcommit_memory; 11 extern int sysctl_overcommit_ratio; 12 extern struct percpu_counter vm_committed_as; 13 14 #ifdef CONFIG_SMP 15 extern s32 vm_committed_as_batch; 16 #else 17 #define vm_committed_as_batch 0 18 #endif 19 20 unsigned long vm_memory_committed(void); 21 22 static inline void vm_acct_memory(long pages) 23 { 24 __percpu_counter_add(&vm_committed_as, pages, vm_committed_as_batch); 25 } 26 27 static 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 */ 51 static 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 */ 71 static inline unsigned long 72 calc_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 */ 83 static inline unsigned long 84 calc_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 #endif /* _LINUX_MMAN_H */ 91