diff options
Diffstat (limited to 'include/linux/mman.h')
-rw-r--r-- | include/linux/mman.h | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/include/linux/mman.h b/include/linux/mman.h new file mode 100644 index 00000000000..18a5689ef74 --- /dev/null +++ b/include/linux/mman.h @@ -0,0 +1,67 @@ +#ifndef _LINUX_MMAN_H +#define _LINUX_MMAN_H + +#include <linux/config.h> +#include <linux/mm.h> + +#include <asm/atomic.h> +#include <asm/mman.h> + +#define MREMAP_MAYMOVE 1 +#define MREMAP_FIXED 2 + +#define OVERCOMMIT_GUESS 0 +#define OVERCOMMIT_ALWAYS 1 +#define OVERCOMMIT_NEVER 2 +extern int sysctl_overcommit_memory; +extern int sysctl_overcommit_ratio; +extern atomic_t vm_committed_space; + +#ifdef CONFIG_SMP +extern void vm_acct_memory(long pages); +#else +static inline void vm_acct_memory(long pages) +{ + atomic_add(pages, &vm_committed_space); +} +#endif + +static inline void vm_unacct_memory(long pages) +{ + vm_acct_memory(-pages); +} + +/* + * Optimisation macro. It is equivalent to: + * (x & bit1) ? bit2 : 0 + * but this version is faster. + * ("bit1" and "bit2" must be single bits) + */ +#define _calc_vm_trans(x, bit1, bit2) \ + ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \ + : ((x) & (bit1)) / ((bit1) / (bit2))) + +/* + * Combine the mmap "prot" argument into "vm_flags" used internally. + */ +static inline unsigned long +calc_vm_prot_bits(unsigned long prot) +{ + return _calc_vm_trans(prot, PROT_READ, VM_READ ) | + _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) | + _calc_vm_trans(prot, PROT_EXEC, VM_EXEC ); +} + +/* + * Combine the mmap "flags" argument into "vm_flags" used internally. + */ +static inline unsigned long +calc_vm_flag_bits(unsigned long flags) +{ + return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) | + _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) | + _calc_vm_trans(flags, MAP_EXECUTABLE, VM_EXECUTABLE) | + _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ); +} + +#endif /* _LINUX_MMAN_H */ |