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 * MAP_EXECUTABLE is completely ignored throughout the kernel.
37 #define LEGACY_MAP_MASK (MAP_SHARED \
55 extern int sysctl_overcommit_memory;
56 extern int sysctl_overcommit_ratio;
57 extern unsigned long sysctl_overcommit_kbytes;
58 extern struct percpu_counter vm_committed_as;
61 extern s32 vm_committed_as_batch;
62 extern void mm_compute_batch(int overcommit_policy);
64 #define vm_committed_as_batch 0
65 static inline void mm_compute_batch(int overcommit_policy)
70 unsigned long vm_memory_committed(void);
72 static inline void vm_acct_memory(long pages)
74 percpu_counter_add_batch(&vm_committed_as, pages, vm_committed_as_batch);
77 static inline void vm_unacct_memory(long pages)
79 vm_acct_memory(-pages);
83 * Allow architectures to handle additional protection and flag bits. The
84 * overriding macros must be defined in the arch-specific asm/mman.h file.
87 #ifndef arch_calc_vm_prot_bits
88 #define arch_calc_vm_prot_bits(prot, pkey) 0
91 #ifndef arch_calc_vm_flag_bits
92 #define arch_calc_vm_flag_bits(flags) 0
95 #ifndef arch_vm_get_page_prot
96 #define arch_vm_get_page_prot(vm_flags) __pgprot(0)
99 #ifndef arch_validate_prot
101 * This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have
102 * already been masked out.
104 * Returns true if the prot flags are valid
106 static inline bool arch_validate_prot(unsigned long prot, unsigned long addr)
108 return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
110 #define arch_validate_prot arch_validate_prot
113 #ifndef arch_validate_flags
115 * This is called from mmap() and mprotect() with the updated vma->vm_flags.
117 * Returns true if the VM_* flags are valid.
119 static inline bool arch_validate_flags(unsigned long flags)
123 #define arch_validate_flags arch_validate_flags
127 * Optimisation macro. It is equivalent to:
128 * (x & bit1) ? bit2 : 0
129 * but this version is faster.
130 * ("bit1" and "bit2" must be single bits)
132 #define _calc_vm_trans(x, bit1, bit2) \
133 ((!(bit1) || !(bit2)) ? 0 : \
134 ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
135 : ((x) & (bit1)) / ((bit1) / (bit2))))
138 * Combine the mmap "prot" argument into "vm_flags" used internally.
140 static inline unsigned long
141 calc_vm_prot_bits(unsigned long prot, unsigned long pkey)
143 return _calc_vm_trans(prot, PROT_READ, VM_READ ) |
144 _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |
145 _calc_vm_trans(prot, PROT_EXEC, VM_EXEC) |
146 arch_calc_vm_prot_bits(prot, pkey);
150 * Combine the mmap "flags" argument into "vm_flags" used internally.
152 static inline unsigned long
153 calc_vm_flag_bits(unsigned long flags)
155 return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
156 _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
157 _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ) |
158 _calc_vm_trans(flags, MAP_SYNC, VM_SYNC ) |
159 arch_calc_vm_flag_bits(flags);
162 unsigned long vm_commit_limit(void);
163 #endif /* _LINUX_MMAN_H */