/*      $NetBSD: subr_disk_open.c,v 1.16 2026/01/04 03:16:38 riastradh 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 1.16 2026/01/04 03:16:38 riastradh 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/sdt.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 = SET_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 = SET_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;
}