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.\" Copyright (c) 2003 Bruce M Simpson <bms@spc.org>
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.Dd July 19, 2003
.Dt VM_MAP_LOOKUP 9
.Os
.Sh NAME
.Nm vm_map_lookup ,
.Nm vm_map_lookup_done
.Nd lookup the vm_object backing a given virtual region
.Sh SYNOPSIS
.In sys/param.h
.In vm/vm.h
.In vm/vm_map.h
.Ft int
.Fo vm_map_lookup
.Fa "vm_map_t *var_map" "vm_offset_t vaddr" "vm_prot_t fault_type"
.Fa "vm_map_entry_t *out_entry" "vm_object_t *object" "vm_pindex_t *pindex"
.Fa "vm_prot_t *out_prot" "boolean_t *wired"
.Fc
.Ft void
.Fn vm_map_lookup_done "vm_map_t map" "vm_map_entry_t entry"
.Sh DESCRIPTION
The
.Fn vm_map_lookup
function attempts to find the
.Vt vm_object ,
page index and protection, for the given virtual address
.Fa vaddr ,
in the map
.Fa var_map ,
assuming a page fault of the type
.Fa fault_type
had occurred.
.Pp
Return values are guaranteed until
.Fn vm_map_lookup_done
is called to release the lock.
.Sh IMPLEMENTATION NOTES
The function
.Fn vm_map_lookup
acquires a read-lock on the map
.Fa *var_map ,
but does not release it.
The caller should invoke
.Fn vm_map_lookup_done
in order to release this lock.
.Sh RETURN VALUES
The
.Fn vm_map_lookup
function returns
.Dv KERN_SUCCESS ,
and sets the
.Fa *object ,
.Fa *pindex ,
.Fa *out_prot ,
and
.Fa *out_entry
arguments appropriately for the hypothetical page fault.
.Sh SEE ALSO
.Xr vm_map 9
.Sh AUTHORS
This manual page was written by
.An Bruce M Simpson Aq bms@spc.org .