1 /* SPDX-License-Identifier: GPL-2.0 */
6 #include <linux/percpu_counter.h>
8 #include <linux/atomic.h>
9 #include <uapi/linux/mman.h>
12 * Arrange for legacy / undefined architecture specific flags to be
13 * ignored by mmap handling code.
19 #define MAP_HUGE_2MB 0
22 #define MAP_HUGE_1GB 0
24 #ifndef MAP_UNINITIALIZED
25 #define MAP_UNINITIALIZED 0
32 * The historical set of flags that all mmap implementations implicitly
33 * support when a ->mmap_validate() op is not provided in file_operations.
35 #define LEGACY_MAP_MASK (MAP_SHARED \
53 extern int sysctl_overcommit_memory;
54 extern int sysctl_overcommit_ratio;
55 extern unsigned long sysctl_overcommit_kbytes;
56 extern struct percpu_counter vm_committed_as;
59 extern s32 vm_committed_as_batch;
60 extern void mm_compute_batch(int overcommit_policy);
62 #define vm_committed_as_batch 0
63 static inline void mm_compute_batch(int overcommit_policy)
68 unsigned long vm_memory_committed(void);
70 static inline void vm_acct_memory(long pages)
72 percpu_counter_add_batch(&vm_committed_as, pages, vm_committed_as_batch);
75 static inline void vm_unacct_memory(long pages)
77 vm_acct_memory(-pages);
81 * Allow architectures to handle additional protection bits
84 #ifndef arch_calc_vm_prot_bits
85 #define arch_calc_vm_prot_bits(prot, pkey) 0
88 #ifndef arch_vm_get_page_prot
89 #define arch_vm_get_page_prot(vm_flags) __pgprot(0)
92 #ifndef arch_validate_prot
94 * This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have
95 * already been masked out.
97 * Returns true if the prot flags are valid
99 static inline bool arch_validate_prot(unsigned long prot, unsigned long addr)
101 return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
103 #define arch_validate_prot arch_validate_prot
107 * Optimisation macro. It is equivalent to:
108 * (x & bit1) ? bit2 : 0
109 * but this version is faster.
110 * ("bit1" and "bit2" must be single bits)
112 #define _calc_vm_trans(x, bit1, bit2) \
113 ((!(bit1) || !(bit2)) ? 0 : \
114 ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
115 : ((x) & (bit1)) / ((bit1) / (bit2))))
118 * Combine the mmap "prot" argument into "vm_flags" used internally.
120 static inline unsigned long
121 calc_vm_prot_bits(unsigned long prot, unsigned long pkey)
123 return _calc_vm_trans(prot, PROT_READ, VM_READ ) |
124 _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |
125 _calc_vm_trans(prot, PROT_EXEC, VM_EXEC) |
126 arch_calc_vm_prot_bits(prot, pkey);
130 * Combine the mmap "flags" argument into "vm_flags" used internally.
132 static inline unsigned long
133 calc_vm_flag_bits(unsigned long flags)
135 return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
136 _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
137 _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ) |
138 _calc_vm_trans(flags, MAP_SYNC, VM_SYNC );
141 unsigned long vm_commit_limit(void);
142 #endif /* _LINUX_MMAN_H */