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 /* 11 * Arrange for legacy / undefined architecture specific flags to be 12 * ignored by mmap handling code. 13 */ 14 #ifndef MAP_32BIT 15 #define MAP_32BIT 0 16 #endif 17 #ifndef MAP_HUGE_2MB 18 #define MAP_HUGE_2MB 0 19 #endif 20 #ifndef MAP_HUGE_1GB 21 #define MAP_HUGE_1GB 0 22 #endif 23 #ifndef MAP_UNINITIALIZED 24 #define MAP_UNINITIALIZED 0 25 #endif 26 #ifndef MAP_SYNC 27 #define MAP_SYNC 0 28 #endif 29 30 /* 31 * The historical set of flags that all mmap implementations implicitly 32 * support when a ->mmap_validate() op is not provided in file_operations. 33 */ 34 #define LEGACY_MAP_MASK (MAP_SHARED \ 35 | MAP_PRIVATE \ 36 | MAP_FIXED \ 37 | MAP_ANONYMOUS \ 38 | MAP_DENYWRITE \ 39 | MAP_EXECUTABLE \ 40 | MAP_UNINITIALIZED \ 41 | MAP_GROWSDOWN \ 42 | MAP_LOCKED \ 43 | MAP_NORESERVE \ 44 | MAP_POPULATE \ 45 | MAP_NONBLOCK \ 46 | MAP_STACK \ 47 | MAP_HUGETLB \ 48 | MAP_32BIT \ 49 | MAP_HUGE_2MB \ 50 | MAP_HUGE_1GB) 51 52 extern int sysctl_overcommit_memory; 53 extern int sysctl_overcommit_ratio; 54 extern unsigned long sysctl_overcommit_kbytes; 55 extern struct percpu_counter vm_committed_as; 56 57 #ifdef CONFIG_SMP 58 extern s32 vm_committed_as_batch; 59 #else 60 #define vm_committed_as_batch 0 61 #endif 62 63 unsigned long vm_memory_committed(void); 64 65 static inline void vm_acct_memory(long pages) 66 { 67 percpu_counter_add_batch(&vm_committed_as, pages, vm_committed_as_batch); 68 } 69 70 static inline void vm_unacct_memory(long pages) 71 { 72 vm_acct_memory(-pages); 73 } 74 75 /* 76 * Allow architectures to handle additional protection bits 77 */ 78 79 #ifndef arch_calc_vm_prot_bits 80 #define arch_calc_vm_prot_bits(prot, pkey) 0 81 #endif 82 83 #ifndef arch_vm_get_page_prot 84 #define arch_vm_get_page_prot(vm_flags) __pgprot(0) 85 #endif 86 87 #ifndef arch_validate_prot 88 /* 89 * This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have 90 * already been masked out. 91 * 92 * Returns true if the prot flags are valid 93 */ 94 static inline bool arch_validate_prot(unsigned long prot) 95 { 96 return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0; 97 } 98 #define arch_validate_prot arch_validate_prot 99 #endif 100 101 /* 102 * Optimisation macro. It is equivalent to: 103 * (x & bit1) ? bit2 : 0 104 * but this version is faster. 105 * ("bit1" and "bit2" must be single bits) 106 */ 107 #define _calc_vm_trans(x, bit1, bit2) \ 108 ((!(bit1) || !(bit2)) ? 0 : \ 109 ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \ 110 : ((x) & (bit1)) / ((bit1) / (bit2)))) 111 112 /* 113 * Combine the mmap "prot" argument into "vm_flags" used internally. 114 */ 115 static inline unsigned long 116 calc_vm_prot_bits(unsigned long prot, unsigned long pkey) 117 { 118 return _calc_vm_trans(prot, PROT_READ, VM_READ ) | 119 _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) | 120 _calc_vm_trans(prot, PROT_EXEC, VM_EXEC) | 121 arch_calc_vm_prot_bits(prot, pkey); 122 } 123 124 /* 125 * Combine the mmap "flags" argument into "vm_flags" used internally. 126 */ 127 static inline unsigned long 128 calc_vm_flag_bits(unsigned long flags) 129 { 130 return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) | 131 _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) | 132 _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ) | 133 _calc_vm_trans(flags, MAP_SYNC, VM_SYNC ); 134 } 135 136 unsigned long vm_commit_limit(void); 137 #endif /* _LINUX_MMAN_H */ 138