noble (9) g_wither_geom.9freebsd.gz

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>.