Copyright (c) 2003 Bruce M Simpson <bms@spc.org>
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$FreeBSD$

.Dd July 19, 2003 .Dt VM_MAP_LOCK 9 .Os .Sh NAME .Nm vm_map_lock , .Nm vm_map_unlock , .Nm vm_map_lock_read , .Nm vm_map_unlock_read , .Nm vm_map_trylock , .Nm vm_map_trylock_read , .Nm vm_map_lock_upgrade , .Nm vm_map_lock_downgrade .Nd vm_map locking macros .Sh SYNOPSIS n sys/param.h n vm/vm.h n vm/vm_map.h .Ft void .Fn vm_map_lock "vm_map_t map" .Ft void .Fn vm_map_unlock "vm_map_t map" .Ft void .Fn vm_map_lock_read "vm_map_t map" .Ft void .Fn vm_map_unlock_read "vm_map_t map" .Ft int .Fn vm_map_trylock "vm_map_t map" .Ft int .Fn vm_map_trylock_read "vm_map_t map" .Ft int .Fn vm_map_lock_upgrade "vm_map_t map" .Ft int .Fn vm_map_lock_downgrade "vm_map_t map" .Sh DESCRIPTION The .Fn vm_map_lock macro obtains an exclusive lock on .Fa map .

p The .Fn vm_map_unlock macro releases an exclusive lock on .Fa map .

p The .Fn vm_map_lock_read macro obtains a read-lock on .Fa map .

p The .Fn vm_map_unlock_read macro releases a read-lock on .Fa map .

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

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

p The .Fn vm_map_lock_upgrade macro attempts to atomically upgrade a read-lock on .Fa map to an exclusive lock.

p The .Fn vm_map_lock_downgrade macro attempts to downgrade an exclusive lock on .Fa map to a read-lock. .Sh IMPLEMENTATION NOTES Currently, all of the locking macros implement their locks as sleep locks. .Sh SEE ALSO .Xr vm_map 9 .Sh AUTHORS This manual page was written by .An Bruce M Simpson Aq bms@spc.org .