80119ef5c8
The atomic_t type is 32bit but a 64bit system can have more than 2^32 pages of virtual address space available. Without this we overflow on ludicrously large mappings Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
70 lines
1.6 KiB
C
70 lines
1.6 KiB
C
#ifndef _LINUX_MMAN_H
|
|
#define _LINUX_MMAN_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
|
|
|
|
#ifdef __KERNEL__
|
|
#include <linux/mm.h>
|
|
|
|
#include <asm/atomic.h>
|
|
|
|
extern int sysctl_overcommit_memory;
|
|
extern int sysctl_overcommit_ratio;
|
|
extern atomic_long_t vm_committed_space;
|
|
|
|
#ifdef CONFIG_SMP
|
|
extern void vm_acct_memory(long pages);
|
|
#else
|
|
static inline void vm_acct_memory(long pages)
|
|
{
|
|
atomic_long_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 /* __KERNEL__ */
|
|
#endif /* _LINUX_MMAN_H */
|