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#ifndef _LINUX_MMAN_H
#define _LINUX_MMAN_H
#include <linux/mm.h>
#include <linux/percpu_counter.h>
#include <linux/atomic.h>
#include <uapi/linux/mman.h>
extern int sysctl_overcommit_memory;
extern int sysctl_overcommit_ratio;
extern struct percpu_counter vm_committed_as;
static inline void vm_acct_memory(long pages)
{
percpu_counter_add(&vm_committed_as, pages);
}
static inline void vm_unacct_memory(long pages)
{
vm_acct_memory(-pages);
}
/*
* Allow architectures to handle additional protection bits
*/
#ifndef arch_calc_vm_prot_bits
#define arch_calc_vm_prot_bits(prot) 0
#endif
#ifndef arch_vm_get_page_prot
#define arch_vm_get_page_prot(vm_flags) __pgprot(0)
#endif
#ifndef arch_validate_prot
/*
* This is called from mprotect(). PROT_GROWSDOWN and PROT_GROWSUP have
* already been masked out.
*
* Returns true if the prot flags are valid
*/
static inline int arch_validate_prot(unsigned long prot)
{
return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
}
#define arch_validate_prot arch_validate_prot
#endif
/*
* 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) |
arch_calc_vm_prot_bits(prot);
}
/*
* 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_LOCKED, VM_LOCKED );
}
#endif /* _LINUX_MMAN_H */
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