NetBSD/sys/kern/subr_disk_open.c

173 lines
4.7 KiB
C

/* $NetBSD: subr_disk_open.c,v 1.15 2020/02/29 14:44:44 mlelstv Exp $ */
/*-
* Copyright (c) 2006 The NetBSD Foundation, Inc.
* 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 FOUNDATION OR CONTRIBUTORS
* 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: subr_disk_open.c,v 1.15 2020/02/29 14:44:44 mlelstv Exp $");
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/disk.h>
#include <sys/disklabel.h>
#include <sys/fcntl.h>
#include <sys/kauth.h>
#include <sys/vnode.h>
#include <miscfs/specfs/specdev.h>
struct vnode *
opendisk(device_t dv)
{
devmajor_t bmajor;
int unit;
struct vnode *tmpvn;
int error;
dev_t dev;
/*
* Lookup major number for disk block device.
*/
bmajor = devsw_name2blk(device_xname(dv), NULL, 0);
if (bmajor == -1)
return NULL;
unit = device_unit(dv);
/*
* Fake a temporary vnode for the disk, open it, and read
* and hash the sectors.
*/
dev = device_is_a(dv, "dk") ? makedev(bmajor, unit) :
MAKEDISKDEV(bmajor, unit, RAW_PART);
if (bdevvp(dev, &tmpvn))
panic("%s: can't alloc vnode for %s", __func__,
device_xname(dv));
vn_lock(tmpvn, LK_EXCLUSIVE | LK_RETRY);
error = VOP_OPEN(tmpvn, FREAD | FSILENT, NOCRED);
if (error) {
/*
* Ignore errors caused by missing device, partition,
* medium, or busy [presumably because of a wedge covering it]
*/
switch (error) {
case ENXIO:
case ENODEV:
case EBUSY:
break;
default:
printf("%s: can't open dev %s (%d)\n",
__func__, device_xname(dv), error);
break;
}
vput(tmpvn);
return NULL;
}
return tmpvn;
}
int
getdisksize(struct vnode *vp, uint64_t *numsecp, unsigned int *secsizep)
{
struct partinfo pi;
struct dkwedge_info dkw;
struct disk *pdk;
unsigned int secsize;
uint64_t numsec;
int error;
/*
* We attempt to get the wedge information first if it exists,
* because the label does not support larger size disks.
*/
error = VOP_IOCTL(vp, DIOCGWEDGEINFO, &dkw, FREAD, NOCRED);
if (error == 0) {
pdk = disk_find(dkw.dkw_parent);
if (pdk != NULL) {
secsize = DEV_BSIZE << pdk->dk_blkshift;
numsec = dkw.dkw_size;
} else
error = ENODEV;
}
if (error) {
error = VOP_IOCTL(vp, DIOCGPARTINFO, &pi, FREAD, NOCRED);
if (error == 0) {
secsize = pi.pi_secsize;
numsec = pi.pi_size;
}
}
if (error == 0 &&
(secsize == 0 || secsize > MAXBSIZE || !powerof2(secsize) ||
numsec == 0)) {
#ifdef DIAGNOSTIC
printf("%s: %s returns invalid disksize values"
" (secsize = %u, numsec = %" PRIu64 ")\n",
__func__,
devsw_blk2name(major(vp->v_specnode->sn_rdev)),
secsize, numsec);
#endif
error = EINVAL;
}
if (error == 0) {
*secsizep = secsize;
*numsecp = numsec;
}
return error;
}
int
getdiskinfo(struct vnode *vp, struct dkwedge_info *dkw)
{
struct partinfo pi;
int error;
dev_t dev = vp->v_specnode->sn_rdev;
if (VOP_IOCTL(vp, DIOCGWEDGEINFO, dkw, FREAD, NOCRED) == 0)
return 0;
if ((error = VOP_IOCTL(vp, DIOCGPARTINFO, &pi, FREAD, NOCRED)) != 0)
return error;
snprintf(dkw->dkw_devname, sizeof(dkw->dkw_devname), "%s%" PRId32 "%c",
devsw_blk2name(major(dev)), DISKUNIT(dev), (char)DISKPART(dev) +
'a');
dkw->dkw_wname[0] = '\0';
snprintf(dkw->dkw_parent, sizeof(dkw->dkw_parent), "%s%" PRId32,
devsw_blk2name(major(dev)), DISKUNIT(dev));
dkw->dkw_size = pi.pi_size;
dkw->dkw_offset = pi.pi_offset;
strlcpy(dkw->dkw_ptype, getfstypename(pi.pi_fstype),
sizeof(dkw->dkw_ptype));
return 0;
}