text: /*-
   * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   *
   * Copyright (c) 2001, 2002 Scott Long <scottl@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 AUTHOR 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 AUTHOR 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.
   *
   * $FreeBSD$
   */
  
  /* udf_vfsops.c */
  /* Implement the VFS side of things */
  
  /*
   * Ok, here's how it goes.  The UDF specs are pretty clear on how each data
   * structure is made up, but not very clear on how they relate to each other.
   * Here is the skinny... This demostrates a filesystem with one file in the
   * root directory.  Subdirectories are treated just as normal files, but they
   * have File Id Descriptors of their children as their file data.  As for the
   * Anchor Volume Descriptor Pointer, it can exist in two of the following three
   * places: sector 256, sector n (the max sector of the disk), or sector
   * n - 256.  It's a pretty good bet that one will exist at sector 256 though.
   * One caveat is unclosed CD media.  For that, sector 256 cannot be written,
   * so the Anchor Volume Descriptor Pointer can exist at sector 512 until the
   * media is closed.
   *
   *  Sector:
   *     256:
   *       n: Anchor Volume Descriptor Pointer
   * n - 256:	|
   *		|
   *		|-->Main Volume Descriptor Sequence
   *			|	|
   *			|	|
   *			|	|-->Logical Volume Descriptor
   *			|			  |
   *			|-->Partition Descriptor  |
   *				|		  |
   *				|		  |
   *				|-->Fileset Descriptor
   *					|
   *					|
   *					|-->Root Dir File Entry
   *						|
   *						|
   *						|-->File data:
   *						    File Id Descriptor
   *							|
   *							|
   *							|-->File Entry
   *								|
   *								|
   *								|-->File data
   */
  #include <sys/types.h>
  #include <sys/param.h>
  #include <sys/systm.h>
  #include <sys/uio.h>
  #include <sys/bio.h>
  #include <sys/buf.h>
  #include <sys/conf.h>
  #include <sys/dirent.h>
  #include <sys/fcntl.h>
  #include <sys/iconv.h>
  #include <sys/kernel.h>
  #include <sys/malloc.h>
  #include <sys/mount.h>
  #include <sys/namei.h>
  #include <sys/priv.h>
  #include <sys/proc.h>
  #include <sys/queue.h>
  #include <sys/vnode.h>
  #include <sys/endian.h>
  
  #include <geom/geom.h>
  #include <geom/geom_vfs.h>
  
  #include <vm/uma.h>
  
  #include <fs/udf/ecma167-udf.h>
  #include <fs/udf/osta.h>
  #include <fs/udf/udf.h>
  #include <fs/udf/udf_mount.h>
  
  static MALLOC_DEFINE(M_UDFMOUNT, "udf_mount", "UDF mount structure");
  MALLOC_DEFINE(M_UDFFENTRY, "udf_fentry", "UDF file entry structure");
  
  struct iconv_functions *udf_iconv = NULL;
  
  /* Zones */
  uma_zone_t udf_zone_trans = NULL;
  uma_zone_t udf_zone_node = NULL;
  uma_zone_t udf_zone_ds = NULL;
  
  static vfs_init_t      udf_init;
  static vfs_uninit_t    udf_uninit;
  static vfs_mount_t     udf_mount;
  static vfs_root_t      udf_root;
  static vfs_statfs_t    udf_statfs;
  static vfs_unmount_t   udf_unmount;
  static vfs_fhtovp_t	udf_fhtovp;
  
  static int udf_find_partmaps(struct udf_mnt *, struct logvol_desc *);
  
  static struct vfsops udf_vfsops = {
  	.vfs_fhtovp =		udf_fhtovp,
  	.vfs_init =		udf_init,
  	.vfs_mount =		udf_mount,
  	.vfs_root =		udf_root,
  	.vfs_statfs =		udf_statfs,
  	.vfs_uninit =		udf_uninit,
  	.vfs_unmount =		udf_unmount,
  	.vfs_vget =		udf_vget,
  };
  VFS_SET(udf_vfsops, udf, VFCF_READONLY);
  
  MODULE_VERSION(udf, 1);
  
  static int udf_mountfs(struct vnode *, struct mount *);
  
  static int
  udf_init(struct vfsconf *foo)
  {
  
  	/*
  	 * This code used to pre-allocate a certain number of pages for each
  	 * pool, reducing the need to grow the zones later on.  UMA doesn't
  	 * advertise any such functionality, unfortunately =-<
  	 */
  	udf_zone_trans = uma_zcreate("UDF translation buffer, zone", MAXNAMLEN *
  	    sizeof(unicode_t), NULL, NULL, NULL, NULL, 0, 0);
  
  	udf_zone_node = uma_zcreate("UDF Node zone", sizeof(struct udf_node),
  	    NULL, NULL, NULL, NULL, 0, 0);
  
  	udf_zone_ds = uma_zcreate("UDF Dirstream zone",
  	    sizeof(struct udf_dirstream), NULL, NULL, NULL, NULL, 0, 0);
  
  	if ((udf_zone_node == NULL) || (udf_zone_trans == NULL) ||
  	    (udf_zone_ds == NULL)) {
  		printf("Cannot create allocation zones.\n");
  		return (ENOMEM);
  	}
  
  	return 0;
  }
  
  static int
  udf_uninit(struct vfsconf *foo)
  {
  
  	if (udf_zone_trans != NULL) {
  		uma_zdestroy(udf_zone_trans);
  		udf_zone_trans = NULL;
  	}
  
  	if (udf_zone_node != NULL) {
  		uma_zdestroy(udf_zone_node);
  		udf_zone_node = NULL;
  	}
  
  	if (udf_zone_ds != NULL) {
  		uma_zdestroy(udf_zone_ds);
  		udf_zone_ds = NULL;
  	}
  
  	return (0);
  }
  
  static int
  udf_mount(struct mount *mp)
  {
  	struct vnode *devvp;	/* vnode of the mount device */
  	struct thread *td;
  	struct udf_mnt *imp = NULL;
  	struct vfsoptlist *opts;
  	char *fspec, *cs_disk, *cs_local;
  	int error, len, *udf_flags;
  	struct nameidata nd, *ndp = &nd;
  
  	td = curthread;
  	opts = mp->mnt_optnew;
  
  	/*
  	 * Unconditionally mount as read-only.
  	 */
  	MNT_ILOCK(mp);
  	mp->mnt_flag |= MNT_RDONLY;
  	MNT_IUNLOCK(mp);
  
  	/*
  	 * No root filesystem support.  Probably not a big deal, since the
  	 * bootloader doesn't understand UDF.
  	 */
  	if (mp->mnt_flag & MNT_ROOTFS)
  		return (ENOTSUP);
  
  	fspec = NULL;
  	error = vfs_getopt(opts, "from", (void **)&fspec, &len);
  	if (!error && fspec[len - 1] != '\0')
  		return (EINVAL);
  
  	if (mp->mnt_flag & MNT_UPDATE) {
  		return (0);
  	}
  
  	/* Check that the mount device exists */
  	if (fspec == NULL)
  		return (EINVAL);
  	NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec, td);
  	if ((error = namei(ndp)))
  		return (error);
  	NDFREE(ndp, NDF_ONLY_PNBUF);
  	devvp = ndp->ni_vp;
  
  	if (vn_isdisk(devvp, &error) == 0) {
  		vput(devvp);
  		return (error);
  	}
  
  	/* Check the access rights on the mount device */
  	error = VOP_ACCESS(devvp, VREAD, td->td_ucred, td);
  	if (error)
  		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
  	if (error) {
  		vput(devvp);
  		return (error);
  	}
  
  	if ((error = udf_mountfs(devvp, mp))) {
  		vrele(devvp);
  		return (error);
  	}
  
  	imp = VFSTOUDFFS(mp);
  
  	udf_flags = NULL;
  	error = vfs_getopt(opts, "flags", (void **)&udf_flags, &len);
  	if (error || len != sizeof(int))
  		return (EINVAL);
  	imp->im_flags = *udf_flags;
  
  	if (imp->im_flags & UDFMNT_KICONV && udf_iconv) {
  		cs_disk = NULL;
  		error = vfs_getopt(opts, "cs_disk", (void **)&cs_disk, &len);
  		if (!error && cs_disk[len - 1] != '\0')
  			return (EINVAL);
  		cs_local = NULL;
  		error = vfs_getopt(opts, "cs_local", (void **)&cs_local, &len);
  		if (!error && cs_local[len - 1] != '\0')
  			return (EINVAL);
  		udf_iconv->open(cs_local, cs_disk, &imp->im_d2l);
  #if 0
  		udf_iconv->open(cs_disk, cs_local, &imp->im_l2d);
  #endif
  	}
  
  	vfs_mountedfrom(mp, fspec);
  	return 0;
  };
  
  /*
   * Check the descriptor tag for both the correct id and correct checksum.
   * Return zero if all is good, EINVAL if not.
   */
  int
  udf_checktag(struct desc_tag *tag, uint16_t id)
  {
  	uint8_t *itag;
  	uint8_t i, cksum = 0;
  
  	itag = (uint8_t *)tag;
  
  	if (le16toh(tag->id) != id)
  		return (EINVAL);
  
  	for (i = 0; i < 16; i++)
  		cksum = cksum + itag[i];
  	cksum = cksum - itag[4];
  
  	if (cksum == tag->cksum)
  		return (0);
  
  	return (EINVAL);
  }
  
  static int
  udf_mountfs(struct vnode *devvp, struct mount *mp)
  {
  	struct buf *bp = NULL;
  	struct cdev *dev;
  	struct anchor_vdp avdp;
  	struct udf_mnt *udfmp = NULL;
  	struct part_desc *pd;
  	struct logvol_desc *lvd;
  	struct fileset_desc *fsd;
  	struct file_entry *root_fentry;
  	uint32_t sector, size, mvds_start, mvds_end;
  	uint32_t logical_secsize;
  	uint32_t fsd_offset = 0;
  	uint16_t part_num = 0, fsd_part = 0;
  	int error = EINVAL;
  	int logvol_found = 0, part_found = 0, fsd_found = 0;
  	int bsize;
  	struct g_consumer *cp;
  	struct bufobj *bo;
  
  	dev = devvp->v_rdev;
  	dev_ref(dev);
  	g_topology_lock();
  	error = g_vfs_open(devvp, &cp, "udf", 0);
  	g_topology_unlock();
  	VOP_UNLOCK(devvp);
  	if (error)
  		goto bail;
  
  	bo = &devvp->v_bufobj;
  
  	if (devvp->v_rdev->si_iosize_max != 0)
  		mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
  	if (mp->mnt_iosize_max > MAXPHYS)
  		mp->mnt_iosize_max = MAXPHYS;
  
  	/* XXX: should be M_WAITOK */
  	udfmp = malloc(sizeof(struct udf_mnt), M_UDFMOUNT,
  	    M_NOWAIT | M_ZERO);
  	if (udfmp == NULL) {
  		printf("Cannot allocate UDF mount struct\n");
  		error = ENOMEM;
  		goto bail;
  	}
  
  	mp->mnt_data = udfmp;
  	mp->mnt_stat.f_fsid.val[0] = dev2udev(devvp->v_rdev);
  	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
  	MNT_ILOCK(mp);
  	mp->mnt_flag |= MNT_LOCAL;
  	mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED;
  	MNT_IUNLOCK(mp);
  	udfmp->im_mountp = mp;
  	udfmp->im_dev = dev;
  	udfmp->im_devvp = devvp;
  	udfmp->im_d2l = NULL;
  	udfmp->im_cp = cp;
  	udfmp->im_bo = bo;
  
  #if 0
  	udfmp->im_l2d = NULL;
  #endif
  	/*
  	 * The UDF specification defines a logical sectorsize of 2048
  	 * for DVD media.
  	 */
  	logical_secsize = 2048;
  
  	if (((logical_secsize % cp->provider->sectorsize) != 0) ||
  	    (logical_secsize < cp->provider->sectorsize)) {
  		error = EINVAL;
  		goto bail;
  	}
  
  	bsize = cp->provider->sectorsize;
  
  	/* 
  	 * Get the Anchor Volume Descriptor Pointer from sector 256.
  	 * XXX Should also check sector n - 256, n, and 512.
  	 */
  	sector = 256;
  	if ((error = bread(devvp, sector * btodb(logical_secsize), bsize,
  			   NOCRED, &bp)) != 0)
  		goto bail;
  	if ((error = udf_checktag((struct desc_tag *)bp->b_data, TAGID_ANCHOR)))
  		goto bail;
  
  	bcopy(bp->b_data, &avdp, sizeof(struct anchor_vdp));
  	brelse(bp);
  	bp = NULL;
  
  	/*
  	 * Extract the Partition Descriptor and Logical Volume Descriptor
  	 * from the Volume Descriptor Sequence.
  	 * XXX Should we care about the partition type right now?
  	 * XXX What about multiple partitions?
  	 */
  	mvds_start = le32toh(avdp.main_vds_ex.loc);
  	mvds_end = mvds_start + (le32toh(avdp.main_vds_ex.len) - 1) / bsize;
  	for (sector = mvds_start; sector < mvds_end; sector++) {
  		if ((error = bread(devvp, sector * btodb(logical_secsize),
  				   bsize, NOCRED, &bp)) != 0) {
  			printf("Can't read sector %d of VDS\n", sector);
  			goto bail;
  		}
  		lvd = (struct logvol_desc *)bp->b_data;
  		if (!udf_checktag(&lvd->tag, TAGID_LOGVOL)) {
  			udfmp->bsize = le32toh(lvd->lb_size);
  			udfmp->bmask = udfmp->bsize - 1;
  			udfmp->bshift = ffs(udfmp->bsize) - 1;
  			fsd_part = le16toh(lvd->_lvd_use.fsd_loc.loc.part_num);
  			fsd_offset = le32toh(lvd->_lvd_use.fsd_loc.loc.lb_num);
  			if (udf_find_partmaps(udfmp, lvd))
  				break;
  			logvol_found = 1;
  		}
  		pd = (struct part_desc *)bp->b_data;
  		if (!udf_checktag(&pd->tag, TAGID_PARTITION)) {
  			part_found = 1;
  			part_num = le16toh(pd->part_num);
  			udfmp->part_len = le32toh(pd->part_len);
  			udfmp->part_start = le32toh(pd->start_loc);
  		}
  
  		brelse(bp); 
  		bp = NULL;
  		if ((part_found) && (logvol_found))
  			break;
  	}
  
  	if (!part_found || !logvol_found) {
  		error = EINVAL;
  		goto bail;
  	}
  
  	if (fsd_part != part_num) {
  		printf("FSD does not lie within the partition!\n");
  		error = EINVAL;
  		goto bail;
  	}
  
  
  	/*
  	 * Grab the Fileset Descriptor
  	 * Thanks to Chuck McCrobie <mccrobie@cablespeed.com> for pointing
  	 * me in the right direction here.
  	 */
  	sector = udfmp->part_start + fsd_offset;
  	if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
  		printf("Cannot read sector %d of FSD\n", sector);
  		goto bail;
  	}
  	fsd = (struct fileset_desc *)bp->b_data;
  	if (!udf_checktag(&fsd->tag, TAGID_FSD)) {
  		fsd_found = 1;
  		bcopy(&fsd->rootdir_icb, &udfmp->root_icb,
  		    sizeof(struct long_ad));
  	}
  
  	brelse(bp);
  	bp = NULL;
  
  	if (!fsd_found) {
  		printf("Couldn't find the fsd\n");
  		error = EINVAL;
  		goto bail;
  	}
  
  	/*
  	 * Find the file entry for the root directory.
  	 */
  	sector = le32toh(udfmp->root_icb.loc.lb_num) + udfmp->part_start;
  	size = le32toh(udfmp->root_icb.len);
  	if ((error = udf_readdevblks(udfmp, sector, size, &bp)) != 0) {
  		printf("Cannot read sector %d\n", sector);
  		goto bail;
  	}
  
  	root_fentry = (struct file_entry *)bp->b_data;
  	if ((error = udf_checktag(&root_fentry->tag, TAGID_FENTRY))) {
  		printf("Invalid root file entry!\n");
  		goto bail;
  	}
  
  	brelse(bp);
  	bp = NULL;
  
  	return 0;
  
  bail:
  	if (udfmp != NULL)
  		free(udfmp, M_UDFMOUNT);
  	if (bp != NULL)
  		brelse(bp);
  	if (cp != NULL) {
  		g_topology_lock();
  		g_vfs_close(cp);
  		g_topology_unlock();
  	}
  	dev_rel(dev);
  	return error;
  };
  
  static int
  udf_unmount(struct mount *mp, int mntflags)
  {
  	struct udf_mnt *udfmp;
  	int error, flags = 0;
  
  	udfmp = VFSTOUDFFS(mp);
  
  	if (mntflags & MNT_FORCE)
  		flags |= FORCECLOSE;
  
  	if ((error = vflush(mp, 0, flags, curthread)))
  		return (error);
  
  	if (udfmp->im_flags & UDFMNT_KICONV && udf_iconv) {
  		if (udfmp->im_d2l)
  			udf_iconv->close(udfmp->im_d2l);
  #if 0
  		if (udfmp->im_l2d)
  			udf_iconv->close(udfmp->im_l2d);
  #endif
  	}
  
  	g_topology_lock();
  	g_vfs_close(udfmp->im_cp);
  	g_topology_unlock();
  	vrele(udfmp->im_devvp);
  	dev_rel(udfmp->im_dev);
  
  	if (udfmp->s_table != NULL)
  		free(udfmp->s_table, M_UDFMOUNT);
  
  	free(udfmp, M_UDFMOUNT);
  
  	mp->mnt_data = NULL;
  	MNT_ILOCK(mp);
  	mp->mnt_flag &= ~MNT_LOCAL;
  	MNT_IUNLOCK(mp);
  
  	return (0);
  }
  
  static int
  udf_root(struct mount *mp, int flags, struct vnode **vpp)
  {
  	struct udf_mnt *udfmp;
  	ino_t id;
  
  	udfmp = VFSTOUDFFS(mp);
  
  	id = udf_getid(&udfmp->root_icb);
  
  	return (udf_vget(mp, id, flags, vpp));
  }
  
  static int
  udf_statfs(struct mount *mp, struct statfs *sbp)
  {
  	struct udf_mnt *udfmp;
  
  	udfmp = VFSTOUDFFS(mp);
  
  	sbp->f_bsize = udfmp->bsize;
  	sbp->f_iosize = udfmp->bsize;
  	sbp->f_blocks = udfmp->part_len;
  	sbp->f_bfree = 0;
  	sbp->f_bavail = 0;
  	sbp->f_files = 0;
  	sbp->f_ffree = 0;
  	return 0;
  }
  
  int
  udf_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
  {
  	struct buf *bp;
  	struct vnode *devvp;
  	struct udf_mnt *udfmp;
  	struct thread *td;
  	struct vnode *vp;
  	struct udf_node *unode;
  	struct file_entry *fe;
  	int error, sector, size;
  
  	error = vfs_hash_get(mp, ino, flags, curthread, vpp, NULL, NULL);
  	if (error || *vpp != NULL)
  		return (error);
  
  	/*
  	 * We must promote to an exclusive lock for vnode creation.  This
  	 * can happen if lookup is passed LOCKSHARED.
   	 */
  	if ((flags & LK_TYPE_MASK) == LK_SHARED) {
  		flags &= ~LK_TYPE_MASK;
  		flags |= LK_EXCLUSIVE;
  	}
  
  	/*
  	 * We do not lock vnode creation as it is believed to be too
  	 * expensive for such rare case as simultaneous creation of vnode
  	 * for same ino by different processes. We just allow them to race
  	 * and check later to decide who wins. Let the race begin!
  	 */
  
  	td = curthread;
  	udfmp = VFSTOUDFFS(mp);
  
  	unode = uma_zalloc(udf_zone_node, M_WAITOK | M_ZERO);
  
  	if ((error = udf_allocv(mp, &vp, td))) {
  		printf("Error from udf_allocv\n");
  		uma_zfree(udf_zone_node, unode);
  		return (error);
  	}
  
  	unode->i_vnode = vp;
  	unode->hash_id = ino;
  	unode->udfmp = udfmp;
  	vp->v_data = unode;
  
  	lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
  	error = insmntque(vp, mp);
  	if (error != 0) {
  		uma_zfree(udf_zone_node, unode);
  		return (error);
  	}
  	error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
  	if (error || *vpp != NULL)
  		return (error);
  
  	/*
  	 * Copy in the file entry.  Per the spec, the size can only be 1 block.
  	 */
  	sector = ino + udfmp->part_start;
  	devvp = udfmp->im_devvp;
  	if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
  		printf("Cannot read sector %d\n", sector);
  		vgone(vp);
  		vput(vp);
  		brelse(bp);
  		*vpp = NULL;
  		return (error);
  	}
  
  	fe = (struct file_entry *)bp->b_data;
  	if (udf_checktag(&fe->tag, TAGID_FENTRY)) {
  		printf("Invalid file entry!\n");
  		vgone(vp);
  		vput(vp);
  		brelse(bp);
  		*vpp = NULL;
  		return (ENOMEM);
  	}
  	size = UDF_FENTRY_SIZE + le32toh(fe->l_ea) + le32toh(fe->l_ad);
  	unode->fentry = malloc(size, M_UDFFENTRY, M_NOWAIT | M_ZERO);
  	if (unode->fentry == NULL) {
  		printf("Cannot allocate file entry block\n");
  		vgone(vp);
  		vput(vp);
  		brelse(bp);
  		*vpp = NULL;
  		return (ENOMEM);
  	}
  
  	bcopy(bp->b_data, unode->fentry, size);
  	
  	brelse(bp);
  	bp = NULL;
  
  	switch (unode->fentry->icbtag.file_type) {
  	default:
  		vp->v_type = VBAD;
  		break;
  	case 4:
  		vp->v_type = VDIR;
  		break;
  	case 5:
  		vp->v_type = VREG;
  		break;
  	case 6:
  		vp->v_type = VBLK;
  		break;
  	case 7:
  		vp->v_type = VCHR;
  		break;
  	case 9:
  		vp->v_type = VFIFO;
  		vp->v_op = &udf_fifoops;
  		break;
  	case 10:
  		vp->v_type = VSOCK;
  		break;
  	case 12:
  		vp->v_type = VLNK;
  		break;
  	}
  
  	if (vp->v_type != VFIFO)
  		VN_LOCK_ASHARE(vp);
  
  	if (ino == udf_getid(&udfmp->root_icb))
  		vp->v_vflag |= VV_ROOT;
  
  	*vpp = vp;
  
  	return (0);
  }
  
  static int
  udf_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
  {
  	struct ifid *ifhp;
  	struct vnode *nvp;
  	struct udf_node *np;
  	off_t fsize;
  	int error;
  
  	ifhp = (struct ifid *)fhp;
  
  	if ((error = VFS_VGET(mp, ifhp->ifid_ino, LK_EXCLUSIVE, &nvp)) != 0) {
  		*vpp = NULLVP;
  		return (error);
  	}
  
  	np = VTON(nvp);
  	fsize = le64toh(np->fentry->inf_len);
  
  	*vpp = nvp;
  	vnode_create_vobject(*vpp, fsize, curthread);
  	return (0);
  }
  
  static int
  udf_find_partmaps(struct udf_mnt *udfmp, struct logvol_desc *lvd)
  {
  	struct part_map_spare *pms;
  	struct regid *pmap_id;
  	struct buf *bp;
  	unsigned char regid_id[UDF_REGID_ID_SIZE + 1];
  	int i, k, ptype, psize, error;
  	uint8_t *pmap = (uint8_t *) &lvd->maps[0];
  
  	for (i = 0; i < le32toh(lvd->n_pm); i++) {
  		ptype = pmap[0];
  		psize = pmap[1];
  		if (((ptype != 1) && (ptype != 2)) ||
  		    ((psize != UDF_PMAP_TYPE1_SIZE) &&
  		     (psize != UDF_PMAP_TYPE2_SIZE))) {
  			printf("Invalid partition map found\n");
  			return (1);
  		}
  
  		if (ptype == 1) {
  			/* Type 1 map.  We don't care */
  			pmap += UDF_PMAP_TYPE1_SIZE;
  			continue;
  		}
  
  		/* Type 2 map.  Gotta find out the details */
  		pmap_id = (struct regid *)&pmap[4];
  		bzero(&regid_id[0], UDF_REGID_ID_SIZE);
  		bcopy(&pmap_id->id[0], &regid_id[0], UDF_REGID_ID_SIZE);
  
  		if (bcmp(&regid_id[0], "*UDF Sparable Partition",
  		    UDF_REGID_ID_SIZE)) {
  			printf("Unsupported partition map: %s\n", &regid_id[0]);
  			return (1);
  		}
  
  		pms = (struct part_map_spare *)pmap;
  		pmap += UDF_PMAP_TYPE2_SIZE;
  		udfmp->s_table = malloc(le32toh(pms->st_size),
  		    M_UDFMOUNT, M_NOWAIT | M_ZERO);
  		if (udfmp->s_table == NULL)
  			return (ENOMEM);
  
  		/* Calculate the number of sectors per packet. */
  		/* XXX Logical or physical? */
  		udfmp->p_sectors = le16toh(pms->packet_len) / udfmp->bsize;
  
  		/*
  		 * XXX If reading the first Sparing Table fails, should look
  		 * for another table.
  		 */
  		if ((error = udf_readdevblks(udfmp, le32toh(pms->st_loc[0]),
  					   le32toh(pms->st_size), &bp)) != 0) {
  			if (bp != NULL)
  				brelse(bp);
  			printf("Failed to read Sparing Table at sector %d\n",
  			    le32toh(pms->st_loc[0]));
  			free(udfmp->s_table, M_UDFMOUNT);
  			return (error);
  		}
  		bcopy(bp->b_data, udfmp->s_table, le32toh(pms->st_size));
  		brelse(bp);
  
  		if (udf_checktag(&udfmp->s_table->tag, 0)) {
  			printf("Invalid sparing table found\n");
  			free(udfmp->s_table, M_UDFMOUNT);
  			return (EINVAL);
  		}
  
  		/* See how many valid entries there are here.  The list is
  		 * supposed to be sorted. 0xfffffff0 and higher are not valid
  		 */
  		for (k = 0; k < le16toh(udfmp->s_table->rt_l); k++) {
  			udfmp->s_table_entries = k;
  			if (le32toh(udfmp->s_table->entries[k].org) >=
  			    0xfffffff0)
  				break;
  		}
  	}
  
  	return (0);
  }
  