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.\" $FreeBSD$ 26.\" 27.Dd January 16, 2004 28.Dt G_GEOM 9 29.Os 30.Sh NAME 31.Nm g_new_geomf , 32.Nm g_destroy_geom 33.Nd "geom management" 34.Sh SYNOPSIS 35.In geom/geom.h 36.Ft "struct g_geom *" 37.Fn g_new_geomf "struct g_class *mp" "const char *fmt" ... 38.Ft void 39.Fn g_destroy_geom "struct g_geom *gp" 40.Sh DESCRIPTION 41The geom (do not confuse 42.Dq geom 43with 44.Dq GEOM ) 45is an instance of a GEOM class. 46For example: in a typical i386 47.Fx 48system, there will be one geom 49of class MBR for each disk. 50The geom's name is not really important, it is only used in the XML 51dump and for debugging purposes. 52There can be many geoms with the same name. 53.Pp 54The 55.Fn g_new_geomf 56function creates a new geom, which will be an instance of the class 57.Fa mp . 58The geom's name is created in a 59.Xr printf 3 Ns 60-like way from the rest of the arguments. 61.Pp 62The 63.Fn g_destroy_geom 64function destroys the given geom immediately and cancels all related pending 65events. 66.Pp 67The 68.Vt g_geom 69structure 70contains fields that should be set by the caller after geom creation, but before 71creating any providers or consumers related to this geom (not all are required): 72.Bl -tag -offset indent -width indent 73.It Vt "g_start_t *" Va start 74Pointer to a function used for I/O processing. 75.It Vt "g_spoiled_t *" Va spoiled 76Pointer to a function used for consumers spoiling. 77.It Vt "g_dumpconf_t *" Va dumpconf 78Pointer to a function used for configuration in XML format dumping. 79.It Vt "g_access_t *" Va access 80Pointer to a function used for access control. 81.It Vt "g_orphan_t *" Va orphan 82Pointer to a function used to inform about orphaned consumer. 83.It Vt "g_ioctl_t *" Va ioctl 84Pointer to a function used for handling ioctl requests. 85.It Vt "void *" Va softc 86Field for private use. 87.El 88.Sh RESTRICTIONS/CONDITIONS 89If you intend to use providers in this geom you must set field 90.Va start 91of your geom. 92.Pp 93If you are planning to use consumers in your geom you must set fields 94.Va orphan 95and 96.Va access 97for it. 98.Pp 99.Fn g_new_geomf : 100.Bl -item -offset indent 101.It 102Class 103.Fa mp 104must be valid (registered in GEOM). 105.It 106The topology lock has to be held. 107.El 108.Pp 109.Fn g_destroy_geom : 110.Bl -item -offset indent 111.It 112The geom cannot possess any providers. 113.It 114The geom cannot possess any consumers. 115.It 116The topology lock has to be held. 117.El 118.Sh RETURN VALUES 119The 120.Fn g_new_geomf 121function 122returns a pointer to the newly created geom. 123.Sh EXAMPLES 124Create an example geom. 125.Bd -literal -offset indent 126static struct geom * 127g_example_start(struct bio *bp) 128{ 129 130 [...] 131} 132 133static void 134g_example_orphan(struct g_consumer *cp) 135{ 136 137 g_topology_assert(); 138 139 [...] 140} 141 142static void 143g_example_spoiled(struct g_consumer *cp) 144{ 145 146 g_topology_assert(); 147 148 [...] 149} 150 151static void 152g_example_access(struct g_provider *pp, int dr, int dw, int de) 153{ 154 155 [...] 156} 157 158static struct g_geom * 159create_example_geom(struct g_class *myclass) 160{ 161 struct g_geom *gp; 162 163 g_topology_lock(); 164 gp = g_new_geomf(myclass, "example_geom"); 165 g_topology_unlock(); 166 gp->start = g_example_start; 167 gp->orphan = g_example_orphan; 168 gp->spoiled = g_example_spoiled; 169 gp->access = g_example_access; 170 gp->softc = NULL; 171 172 return (gp); 173} 174 175static int 176destroy_example_geom(struct g_geom *gp) 177{ 178 179 g_topology_lock(); 180 if (!LIST_EMPTY(&gp->provider) || 181 !LIST_EMPTY(&gp->consumer)) { 182 g_topology_unlock(); 183 return (EBUSY); 184 } 185 g_destroy_geom(gp); 186 g_topology_unlock(); 187 188 return (0); 189} 190.Ed 191.Sh SEE ALSO 192.Xr geom 4 , 193.Xr DECLARE_GEOM_CLASS 9 , 194.Xr g_access 9 , 195.Xr g_attach 9 , 196.Xr g_bio 9 , 197.Xr g_consumer 9 , 198.Xr g_data 9 , 199.Xr g_event 9 , 200.Xr g_provider 9 , 201.Xr g_provider_by_name 9 , 202.Xr g_wither_geom 9 203.Sh AUTHORS 204.An -nosplit 205This manual page was written by 206.An Pawel Jakub Dawidek Aq Mt pjd@FreeBSD.org . 207