| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef _LINUX_MMAN_H |
| 3 | #define _LINUX_MMAN_H |
| 4 | |
| 5 | #include <linux/mm.h> |
| 6 | #include <linux/percpu_counter.h> |
| 7 | |
| 8 | #include <linux/atomic.h> |
| 9 | #include <uapi/linux/mman.h> |
| 10 | |
| 11 | extern int sysctl_overcommit_memory; |
| 12 | extern int sysctl_overcommit_ratio; |
| 13 | extern unsigned long sysctl_overcommit_kbytes; |
| 14 | extern struct percpu_counter vm_committed_as; |
| 15 | |
| 16 | #ifdef CONFIG_SMP |
| 17 | extern s32 vm_committed_as_batch; |
| 18 | #else |
| 19 | #define vm_committed_as_batch 0 |
| 20 | #endif |
| 21 | |
| 22 | unsigned long vm_memory_committed(void); |
| 23 | |
| 24 | static inline void vm_acct_memory(long pages) |
| 25 | { |
| 26 | percpu_counter_add_batch(&vm_committed_as, pages, vm_committed_as_batch); |
| 27 | } |
| 28 | |
| 29 | static inline void vm_unacct_memory(long pages) |
| 30 | { |
| 31 | vm_acct_memory(-pages); |
| 32 | } |
| 33 | |
| 34 | /* |
| 35 | * Allow architectures to handle additional protection bits |
| 36 | */ |
| 37 | |
| 38 | #ifndef arch_calc_vm_prot_bits |
| 39 | #define arch_calc_vm_prot_bits(prot, pkey) 0 |
| 40 | #endif |
| 41 | |
| 42 | #ifndef arch_vm_get_page_prot |
| 43 | #define arch_vm_get_page_prot(vm_flags) __pgprot(0) |
| 44 | #endif |
| 45 | |
| 46 | #ifndef arch_validate_prot |
| 47 | /* |
| 48 | * This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have |
| 49 | * already been masked out. |
| 50 | * |
| 51 | * Returns true if the prot flags are valid |
| 52 | */ |
| 53 | static inline bool arch_validate_prot(unsigned long prot) |
| 54 | { |
| 55 | return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0; |
| 56 | } |
| 57 | #define arch_validate_prot arch_validate_prot |
| 58 | #endif |
| 59 | |
| 60 | /* |
| 61 | * Optimisation macro. It is equivalent to: |
| 62 | * (x & bit1) ? bit2 : 0 |
| 63 | * but this version is faster. |
| 64 | * ("bit1" and "bit2" must be single bits) |
| 65 | */ |
| 66 | #define _calc_vm_trans(x, bit1, bit2) \ |
| 67 | ((!(bit1) || !(bit2)) ? 0 : \ |
| 68 | ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \ |
| 69 | : ((x) & (bit1)) / ((bit1) / (bit2)))) |
| 70 | |
| 71 | /* |
| 72 | * Combine the mmap "prot" argument into "vm_flags" used internally. |
| 73 | */ |
| 74 | static inline unsigned long |
| 75 | calc_vm_prot_bits(unsigned long prot, unsigned long pkey) |
| 76 | { |
| 77 | return _calc_vm_trans(prot, PROT_READ, VM_READ ) | |
| 78 | _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) | |
| 79 | _calc_vm_trans(prot, PROT_EXEC, VM_EXEC) | |
| 80 | arch_calc_vm_prot_bits(prot, pkey); |
| 81 | } |
| 82 | |
| 83 | /* |
| 84 | * Combine the mmap "flags" argument into "vm_flags" used internally. |
| 85 | */ |
| 86 | static inline unsigned long |
| 87 | calc_vm_flag_bits(unsigned long flags) |
| 88 | { |
| 89 | return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) | |
| 90 | _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) | |
| 91 | _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ); |
| 92 | } |
| 93 | |
| 94 | unsigned long vm_commit_limit(void); |
| 95 | #endif /* _LINUX_MMAN_H */ |