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.Dd January 16, 2004
.Dt G_WITHER_GEOM 9
.Os
.Sh NAME
.Nm g_wither_geom
.Nd "destroy geom and related 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 on each provider of the given geom (in the
orphaning process) and waits for a chance to destroy the geom.
If the access count of any possessed consumer goes to 0, the consumer will be
detached and destroyed automatically.
If the last consumer attached to any possessed provider will be detached,
the 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 of and set to
.Dv NULL .
Note that the
.Fn g_wither_geom
function gives no guarantee that the geom will be immediately destroyed, mostly
because the access counts of the geom's consumers and providers may not be 0.
That is why calling this function for every geom from a given class is not enough
to be sure that the 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 geom 4 ,
.Xr DECLARE_GEOM_CLASS 9 ,
.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 .