domcaps.c revision 843e19887f64dde75055cf8842fc4db2171eff45
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* This rather uninspiring device enables userland to discover if
* the current kernel is actually a dom0 or other domain e.g. domU.
*/
#include <sys/types.h>
#include <sys/file.h>
#include <sys/errno.h>
#include <sys/open.h>
#include <sys/cred.h>
#include <sys/conf.h>
#include <sys/stat.h>
#include <sys/modctl.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/hypervisor.h>
#include <sys/sysmacros.h>
#include <sys/domcaps_impl.h>
static dev_info_t *domcaps_devi;
/*ARGSUSED*/
static int
domcaps_getinfo(dev_info_t *devi, ddi_info_cmd_t cmd, void *arg, void **result)
{
if (getminor((dev_t)arg) != DOMCAPS_MINOR)
return (DDI_FAILURE);
switch (cmd) {
case DDI_INFO_DEVT2DEVINFO:
*result = domcaps_devi;
break;
case DDI_INFO_DEVT2INSTANCE:
*result = 0;
break;
default:
return (DDI_FAILURE);
}
return (DDI_SUCCESS);
}
static int
domcaps_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
{
if (cmd != DDI_ATTACH)
return (DDI_FAILURE);
if (ddi_create_minor_node(devi, ddi_get_name(devi), S_IFCHR,
ddi_get_instance(devi), DDI_PSEUDO, 0) != DDI_SUCCESS)
return (DDI_FAILURE);
domcaps_devi = devi;
ddi_report_dev(devi);
return (DDI_SUCCESS);
}
static int
domcaps_detach(dev_info_t *devi, ddi_detach_cmd_t cmd)
{
if (cmd != DDI_DETACH)
return (DDI_FAILURE);
ddi_remove_minor_node(devi, NULL);
domcaps_devi = NULL;
return (DDI_SUCCESS);
}
/*ARGSUSED1*/
static int
domcaps_open(dev_t *dev, int flag, int otyp, cred_t *cr)
{
return (getminor(*dev) == DOMCAPS_MINOR ? 0 : ENXIO);
}
/*ARGSUSED*/
static int
domcaps_read(dev_t dev, uio_t *uio, cred_t *cr)
{
if (DOMAIN_IS_INITDOMAIN(xen_info)) {
static char data[] = "control_d\n";
size_t nbytes;
if (uio->uio_loffset > sizeof (data))
return (0);
nbytes = MIN(uio->uio_resid, sizeof (data) - uio->uio_loffset);
return (uiomove(data + uio->uio_loffset, nbytes,
UIO_READ, uio));
}
return (0);
}
static struct cb_ops domcaps_cb_ops = {
domcaps_open,
nulldev, /* close */
nodev, /* strategy */
nodev, /* print */
nodev, /* dump */
domcaps_read,
nodev, /* write */
nodev, /* ioctl */
nodev, /* devmap */
nodev, /* mmap */
nodev, /* segmap */
nochpoll, /* poll */
ddi_prop_op,
NULL,
D_64BIT | D_MP,
CB_REV,
NULL,
NULL
};
static struct dev_ops domcaps_dv_ops = {
DEVO_REV,
0,
domcaps_getinfo,
nulldev, /* identify */
nulldev, /* probe */
domcaps_attach,
domcaps_detach,
nodev, /* reset */
&domcaps_cb_ops,
NULL, /* struct bus_ops */
NULL /* power */
};
static struct modldrv modldrv = {
&mod_driverops,
"hypervisor capabilities driver %I%",
&domcaps_dv_ops
};
static struct modlinkage modl = {
MODREV_1,
{
(void *)&modldrv,
NULL /* null termination */
}
};
int
_init(void)
{
return (mod_install(&modl));
}
int
_fini(void)
{
return (mod_remove(&modl));
}
int
_info(struct modinfo *modinfo)
{
return (mod_info(&modl, modinfo));
}