NAME

     g_wither_geom — destroy geom and related providers and consumers when you get a chance

SYNOPSIS

     #include <geom/geom.h>

     void
     g_wither_geom(struct g_geom *gp, int error);

DESCRIPTION

     The g_wither_geom() function tells GEOM that geom 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.

     This is an automatic “garbage collect” to avoid duplicated code in all classes.  Before it
     is called, field softc should be disposed of and set to NULL.  Note that the 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.

RESTRICTIONS/CONDITIONS

     The argument error must be nonzero.

     The topology lock has to be held.

SEE ALSO

     geom(4), DECLARE_GEOM_CLASS(9), g_access(9), g_attach(9), g_bio(9), g_consumer(9),
     g_data(9), g_event(9), g_geom(9), g_provider(9), g_provider_by_name(9)

AUTHORS

     This manual page was written by Pawel Jakub Dawidek <pjd@FreeBSD.org>.