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author | pjd <pjd@FreeBSD.org> | 2004-02-11 10:06:18 +0000 |
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committer | pjd <pjd@FreeBSD.org> | 2004-02-11 10:06:18 +0000 |
commit | dbc7255199dc5592095e7b60e310c520a91641bb (patch) | |
tree | 343cd26c39251e0b38b336e71722a99c8b1510da /share/man/man9/g_geom.9 | |
parent | d2298f1b5c0d5a034a5957fc6dd651a04fb8626f (diff) | |
download | FreeBSD-src-dbc7255199dc5592095e7b60e310c520a91641bb.zip FreeBSD-src-dbc7255199dc5592095e7b60e310c520a91641bb.tar.gz |
Added first part of GEOM kernel API manuals pages.
Documented function and macros are:
- DECLARE_GEOM_CLASS(),
- g_attach(),
- g_detach(),
- g_new_bio(),
- g_clone_bio(),
- g_destroy_bio(),
- g_new_consumer(),
- g_destroy_consumer(),
- g_read_data(),
- g_write_data(),
- g_post_event(),
- g_waitfor_event(),
- g_cancel_event(),
- g_new_geomf(),
- g_destroy_geom(),
- g_new_providerf(),
- g_destroy_provider(),
- g_error_provider(),
- g_provider_by_name(),
- g_wither_geom().
and more to come.
I want to thanks following people for help with those documents:
Slawek Zak <zaks@prioris.mini.pw.edu.pl>
Simon L. Nielsen <simon@FreeBSD.org>
Pieter de Boer <g.p.de.boer@st.hanze.nl>
and of course
Poul-Henning Kamp <phk@FreeBSD.org>
Reviewed by: phk, scottl
Approved by: phk, scottl (mentor)
Diffstat (limited to 'share/man/man9/g_geom.9')
-rw-r--r-- | share/man/man9/g_geom.9 | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/share/man/man9/g_geom.9 b/share/man/man9/g_geom.9 new file mode 100644 index 0000000..febc55b --- /dev/null +++ b/share/man/man9/g_geom.9 @@ -0,0 +1,202 @@ +.\" +.\" Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org> +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, +.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd January 16, 2004 +.Dt g_geom 9 +.Os +.Sh NAME +.Nm g_new_geomf , +.Nm g_destroy_geom +.Nd "geom management" +.Sh SYNOPSIS +.In geom/geom.h +.Ft "struct g_geom *" +.Fn g_new_geomf "struct g_class *mp" "const char *fmt" ... +.Ft void +.Fn g_destroy_geom "struct g_geom *gp" +.Sh DESCRIPTION +The geom (do not confuse +.Dq geom +with +.Dq GEOM ) +is an instance of a GEOM class. +For example: in a typical i386 FreeBSD system, there will be one geom +of class MBR for each disk. +The geom's name is not really important, it is only used in the XML +dump and for debugging purposes. +There can be many geoms with the same name. +.Pp +The +.Fn g_new_geomf +function creates a new geom, which will be an instance of the class +.Fa mp . +The geom name is created in a printf\-like way from the rest of the arguments. +.Pp +The +.Fn g_destroy_geom +function destroys the given geom imediately and cancels all related pending +events. +.Pp +Structure +.Vt g_geom +contains fields, that should be set by the caller after geom creation, but before +creating any providers or consumers related to this geom (not all are required): +.Bl -inset -offset indent +.It Vt "g_start_t *" Va start +Pointer to a function used for I/O processing. +.It Vt "g_spoiled_t *" Va spoiled +Pointer to a function used for consumers spoiling. +.It Vt "g_dumpconf_t *" Va dumpconf +Pointer to a function used for configuration in XML format dumping. +.It Vt "g_access_t *" Va access +Pointer to a function used for access control. +.It Vt "g_orphan_t *" Va orphan +Pointer to a function used to inform about orphaned consumer. +.It Vt "g_ioctl_t *" Va ioctl +Pointer to a function used for handling ioctl requests. +.It Vt "void *" Va softc +Field for private use. +.El +.Sh RESTRICTIONS/CONDITIONS +If you intend to use providers in this geom you must set field +.Va start +of your geom. +.Pp +If you are planning to use consumers in your geom you must set fields +.Va orphan +and +.Va access +for it. +.Pp +.Fn g_new_geomf : +.Bl -item -offset indent +.It +Class +.Fa mp +must be valid (registered in GEOM). +.It +The topology lock has to be held. +.El +.Pp +.Fn g_destroy_geom : +.Bl -item -offset indent +.It +The geom can not posses any providers. +.It +The geom can not posses any consumers. +.It +The topology lock has to be held. +.El +.Sh RETURN VALUES +.Fn g_new_geomf +returns a pointer to the newly created geom or +.Dv NULL +if an error occured. +.Sh EXAMPLES +Create an example geom. +.Bd -literal -offset indent +static struct geom * +g_example_start(struct bio *bp) +{ + + [...] +} + +static void +g_example_orphan(struct g_consumer *cp) +{ + + g_topology_assert(); + + [...] +} + +static void +g_example_spoiled(struct g_consumer *cp) +{ + + g_topology_assert(); + + [...] +} + +static void +g_example_access(struct g_provider *pp, int dr, int dw, int de) +{ + + [...] +} + +static struct g_geom * +create_example_geom(struct g_class *myclass) +{ + struct g_geom *gp; + + g_topology_lock(); + gp = g_new_geomf(myclass, "example_geom"); + g_topology_unlock(); + if (gp != NULL) { + gp->start = g_example_start; + gp->orphan = g_example_orphan; + gp->spoiled = g_example_spoiled; + gp->access = g_example_access; + gp->softc = NULL; + } + + return (gp); +} + +static int +destroy_example_geom(struct g_geom *gp) +{ + + g_topology_lock(); + if (!LIST_EMPTY(&gp->provider) || + !LIST_EMPTY(&gp->consumer)) { + g_topology_unlock(); + return (EBUSY); + } + g_destroy_geom(gp); + g_topology_unlock(); + + return (0); +} +.Ed +.Sh SEE ALSO +.Xr DECLARE_GEOM_CLASS 9 , +.Xr geom 4 , +.Xr g_attach 9 , +.Xr g_bio 9 , +.Xr g_consumer 9 , +.Xr g_data 9 , +.Xr g_event 9 , +.Xr g_provider 9 , +.Xr g_provider_by_name 9 , +.Xr g_wither_geom 9 +.Sh AUTHORS +.An -nosplit +This manual page was written by +.An Pawel Jakub Dawidek Aq pjd@FreeBSD.org . |