NAME

       vm_map_lock,  vm_map_unlock,  vm_map_lock_read,  vm_map_unlock_read, vm_map_trylock, vm_map_trylock_read,
       vm_map_lock_upgrade, vm_map_lock_downgrade — vm_map locking macros

SYNOPSIS

       #include <sys/param.h>
       #include <vm/vm.h>
       #include <vm/vm_map.h>

       void
       vm_map_lock(vm_map_t map);

       void
       vm_map_unlock(vm_map_t map);

       void
       vm_map_lock_read(vm_map_t map);

       void
       vm_map_unlock_read(vm_map_t map);

       int
       vm_map_trylock(vm_map_t map);

       int
       vm_map_trylock_read(vm_map_t map);

       int
       vm_map_lock_upgrade(vm_map_t map);

       int
       vm_map_lock_downgrade(vm_map_t map);

DESCRIPTION

       The vm_map_lock() macro obtains an exclusive lock on map.

       The vm_map_unlock() macro releases an exclusive lock on map.

       The vm_map_lock_read() macro obtains a read-lock on map.

       The vm_map_unlock_read() macro releases a read-lock on map.

       The vm_map_trylock() macro attempts to obtain an exclusive lock on map.  It returns  FALSE  if  the  lock
       cannot be immediately acquired; otherwise return TRUE with the lock acquired.

       The  vm_map_trylock_read()  macro  attempts  to  obtain a read-lock on map.  It returns FALSE if the lock
       cannot be immediately acquired; otherwise return TRUE with the lock acquired.

       The vm_map_lock_upgrade() macro attempts to atomically upgrade a read-lock on map to an exclusive lock.

       The vm_map_lock_downgrade() macro attempts to downgrade an exclusive lock on map to a read-lock.

IMPLEMENTATION NOTES

       Currently, all of the locking macros implement their locks as sleep locks.

SEE ALSO

       vm_map(9)

AUTHORS

       This manual page was written by Bruce M Simpson <bms@spc.org>.

Debian                                            July 19, 2003                                   VM_MAP_LOCK(9)