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.Dd January 16, 2004
.Dt g_wither_geom 9
.Os
.Sh NAME
.Nm g_wither_geom
.Nd "destroy geom and releated providers and consumers when you get a chance"
.Sh SYNOPSIS
.In geom/geom.h
.Ft void
.Fn g_wither_geom "struct g_geom *gp" "int error"
.Sh DESCRIPTION
The
.Fn g_wither_geom
function tells GEOM that geom
.Fa gp
is to be destroyed.
GEOM sets an error for every provider related to the given geom (in
orphan process) and waits for a chance to destroy the geom.
If access count of any possessed consumer goes to 0, consumer will be
detached and destroyed automatically.
If last consumer attached to any possesed provider will be detached,
provider will be destroyed.
If there are no more providers nor consumers, the geom will be
destroyed.
.Pp
This is an automatic
.Dq garbage collect
to avoid duplicated code in all classes.
Before it is called, field
.Va softc
should be disposed off and set to
.Dv NULL .
Note that the
.Fn g_wither_geom
function gives no guarantee that geom will be immediately destroyed, mostly
because access counts of corresponding consumers and providers may not be 0.
That is why calling this function for every geom from given class is not enough
to be sure that class can be unloaded.
.Sh RESTRICTIONS/CONDITIONS
The argument
.Fa error
must be nonzero.
.Pp
The topology lock has to be held.
.Sh SEE ALSO
.Xr DECLARE_GEOM_CLASS 9 ,
.Xr geom 4 ,
.Xr g_access 9 ,
.Xr g_attach 9 ,
.Xr g_bio 9 ,
.Xr g_consumer 9 ,
.Xr g_data 9 ,
.Xr g_event 9 ,
.Xr g_geom 9 ,
.Xr g_provider 9 ,
.Xr g_provider_by_name 9
.Sh AUTHORS
.An -nosplit
This manual page was written by
.An Pawel Jakub Dawidek Aq pjd@FreeBSD.org .