1.\" 2.\" Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org> 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 15.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 18.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24.\" 25.Dd January 16, 2004 26.Dt G_WITHER_GEOM 9 27.Os 28.Sh NAME 29.Nm g_wither_geom 30.Nd "destroy geom and related providers and consumers when you get a chance" 31.Sh SYNOPSIS 32.In geom/geom.h 33.Ft void 34.Fn g_wither_geom "struct g_geom *gp" "int error" 35.Sh DESCRIPTION 36The 37.Fn g_wither_geom 38function tells GEOM that geom 39.Fa gp 40is to be destroyed. 41GEOM sets an error on each provider of the given geom (in the 42orphaning process) and waits for a chance to destroy the geom. 43If the access count of any possessed consumer goes to 0, the consumer will be 44detached and destroyed automatically. 45If the last consumer attached to any possessed provider will be detached, 46the provider will be destroyed. 47If there are no more providers nor consumers, the geom will be 48destroyed. 49.Pp 50This is an automatic 51.Dq garbage collect 52to avoid duplicated code in all classes. 53Before it is called, field 54.Va softc 55should be disposed of and set to 56.Dv NULL . 57Note that the 58.Fn g_wither_geom 59function gives no guarantee that the geom will be immediately destroyed, mostly 60because the access counts of the geom's consumers and providers may not be 0. 61That is why calling this function for every geom from a given class is not enough 62to be sure that the class can be unloaded. 63.Sh RESTRICTIONS/CONDITIONS 64The argument 65.Fa error 66must be nonzero. 67.Pp 68The topology lock has to be held. 69.Sh SEE ALSO 70.Xr geom 4 , 71.Xr DECLARE_GEOM_CLASS 9 , 72.Xr g_access 9 , 73.Xr g_attach 9 , 74.Xr g_bio 9 , 75.Xr g_consumer 9 , 76.Xr g_data 9 , 77.Xr g_event 9 , 78.Xr g_geom 9 , 79.Xr g_provider 9 , 80.Xr g_provider_by_name 9 81.Sh AUTHORS 82.An -nosplit 83This manual page was written by 84.An Pawel Jakub Dawidek Aq Mt pjd@FreeBSD.org . 85