NetBSD/sys/kern/subr_disk_open.c
mlelstv 49be4d025a Add helper function that determines the size and block size of a disk device.
For now we query
- the disk label
- the wedge info and data from disk(9)
2010-01-30 11:57:17 +00:00

111 lines
3.2 KiB
C

/* $NetBSD: subr_disk_open.c,v 1.2 2010/01/30 11:57:17 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 1.2 2010/01/30 11:57:17 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>
struct vnode *
opendisk(struct device *dv)
{
int bmajor, bminor;
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;
bminor = minor(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, bminor) :
MAKEDISKDEV(bmajor, bminor, RAW_PART);
if (bdevvp(dev, &tmpvn))
panic("%s: can't alloc vnode for %s", __func__,
device_xname(dv));
error = VOP_OPEN(tmpvn, FREAD, NOCRED);
if (error) {
#ifndef DEBUG
/*
* Ignore errors caused by missing device, partition,
* or medium.
*/
if (error != ENXIO && error != ENODEV)
#endif
printf("%s: can't open dev %s (%d)\n",
__func__, device_xname(dv), error);
vput(tmpvn);
return NULL;
}
return tmpvn;
}
int
getdisksize(struct vnode *vp, uint64_t *numsecp, unsigned *secsizep)
{
struct partinfo dpart;
struct dkwedge_info dkw;
struct disk *pdk;
int error;
error = VOP_IOCTL(vp, DIOCGPART, &dpart, FREAD, NOCRED);
if (error == 0) {
*secsizep = dpart.disklab->d_secsize;
*numsecp = dpart.part->p_size;
return 0;
}
error = VOP_IOCTL(vp, DIOCGWEDGEINFO, &dkw, FREAD, NOCRED);
if (error == 0) {
pdk = disk_find(dkw.dkw_parent);
if (pdk != NULL) {
*secsizep = DEV_BSIZE << pdk->dk_blkshift;
*numsecp = dkw.dkw_size;
} else
error = ENODEV;
}
return error;
}