xref: /freebsd/sys/fs/udf/udf_vfsops.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*-
2  * Copyright (c) 2001, 2002 Scott Long <scottl@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 /* udf_vfsops.c */
30 /* Implement the VFS side of things */
31 
32 /*
33  * Ok, here's how it goes.  The UDF specs are pretty clear on how each data
34  * structure is made up, but not very clear on how they relate to each other.
35  * Here is the skinny... This demostrates a filesystem with one file in the
36  * root directory.  Subdirectories are treated just as normal files, but they
37  * have File Id Descriptors of their children as their file data.  As for the
38  * Anchor Volume Descriptor Pointer, it can exist in two of the following three
39  * places: sector 256, sector n (the max sector of the disk), or sector
40  * n - 256.  It's a pretty good bet that one will exist at sector 256 though.
41  * One caveat is unclosed CD media.  For that, sector 256 cannot be written,
42  * so the Anchor Volume Descriptor Pointer can exist at sector 512 until the
43  * media is closed.
44  *
45  *  Sector:
46  *     256:
47  *       n: Anchor Volume Descriptor Pointer
48  * n - 256:	|
49  *		|
50  *		|-->Main Volume Descriptor Sequence
51  *			|	|
52  *			|	|
53  *			|	|-->Logical Volume Descriptor
54  *			|			  |
55  *			|-->Partition Descriptor  |
56  *				|		  |
57  *				|		  |
58  *				|-->Fileset Descriptor
59  *					|
60  *					|
61  *					|-->Root Dir File Entry
62  *						|
63  *						|
64  *						|-->File data:
65  *						    File Id Descriptor
66  *							|
67  *							|
68  *							|-->File Entry
69  *								|
70  *								|
71  *								|-->File data
72  */
73 #include <sys/types.h>
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/uio.h>
77 #include <sys/bio.h>
78 #include <sys/buf.h>
79 #include <sys/conf.h>
80 #include <sys/dirent.h>
81 #include <sys/fcntl.h>
82 #include <sys/iconv.h>
83 #include <sys/kernel.h>
84 #include <sys/malloc.h>
85 #include <sys/mount.h>
86 #include <sys/namei.h>
87 #include <sys/priv.h>
88 #include <sys/proc.h>
89 #include <sys/queue.h>
90 #include <sys/vnode.h>
91 #include <sys/endian.h>
92 
93 #include <geom/geom.h>
94 #include <geom/geom_vfs.h>
95 
96 #include <vm/uma.h>
97 
98 #include <fs/udf/ecma167-udf.h>
99 #include <fs/udf/osta.h>
100 #include <fs/udf/udf.h>
101 #include <fs/udf/udf_mount.h>
102 
103 static MALLOC_DEFINE(M_UDFMOUNT, "udf_mount", "UDF mount structure");
104 MALLOC_DEFINE(M_UDFFENTRY, "udf_fentry", "UDF file entry structure");
105 
106 struct iconv_functions *udf_iconv = NULL;
107 
108 /* Zones */
109 uma_zone_t udf_zone_trans = NULL;
110 uma_zone_t udf_zone_node = NULL;
111 uma_zone_t udf_zone_ds = NULL;
112 
113 static vfs_init_t      udf_init;
114 static vfs_uninit_t    udf_uninit;
115 static vfs_mount_t     udf_mount;
116 static vfs_root_t      udf_root;
117 static vfs_statfs_t    udf_statfs;
118 static vfs_unmount_t   udf_unmount;
119 static vfs_fhtovp_t	udf_fhtovp;
120 
121 static int udf_find_partmaps(struct udf_mnt *, struct logvol_desc *);
122 
123 static struct vfsops udf_vfsops = {
124 	.vfs_fhtovp =		udf_fhtovp,
125 	.vfs_init =		udf_init,
126 	.vfs_mount =		udf_mount,
127 	.vfs_root =		udf_root,
128 	.vfs_statfs =		udf_statfs,
129 	.vfs_uninit =		udf_uninit,
130 	.vfs_unmount =		udf_unmount,
131 	.vfs_vget =		udf_vget,
132 };
133 VFS_SET(udf_vfsops, udf, VFCF_READONLY);
134 
135 MODULE_VERSION(udf, 1);
136 
137 static int udf_mountfs(struct vnode *, struct mount *);
138 
139 static int
140 udf_init(struct vfsconf *foo)
141 {
142 
143 	/*
144 	 * This code used to pre-allocate a certain number of pages for each
145 	 * pool, reducing the need to grow the zones later on.  UMA doesn't
146 	 * advertise any such functionality, unfortunately =-<
147 	 */
148 	udf_zone_trans = uma_zcreate("UDF translation buffer, zone", MAXNAMLEN *
149 	    sizeof(unicode_t), NULL, NULL, NULL, NULL, 0, 0);
150 
151 	udf_zone_node = uma_zcreate("UDF Node zone", sizeof(struct udf_node),
152 	    NULL, NULL, NULL, NULL, 0, 0);
153 
154 	udf_zone_ds = uma_zcreate("UDF Dirstream zone",
155 	    sizeof(struct udf_dirstream), NULL, NULL, NULL, NULL, 0, 0);
156 
157 	if ((udf_zone_node == NULL) || (udf_zone_trans == NULL) ||
158 	    (udf_zone_ds == NULL)) {
159 		printf("Cannot create allocation zones.\n");
160 		return (ENOMEM);
161 	}
162 
163 	return 0;
164 }
165 
166 static int
167 udf_uninit(struct vfsconf *foo)
168 {
169 
170 	if (udf_zone_trans != NULL) {
171 		uma_zdestroy(udf_zone_trans);
172 		udf_zone_trans = NULL;
173 	}
174 
175 	if (udf_zone_node != NULL) {
176 		uma_zdestroy(udf_zone_node);
177 		udf_zone_node = NULL;
178 	}
179 
180 	if (udf_zone_ds != NULL) {
181 		uma_zdestroy(udf_zone_ds);
182 		udf_zone_ds = NULL;
183 	}
184 
185 	return (0);
186 }
187 
188 static int
189 udf_mount(struct mount *mp)
190 {
191 	struct vnode *devvp;	/* vnode of the mount device */
192 	struct thread *td;
193 	struct udf_mnt *imp = 0;
194 	struct vfsoptlist *opts;
195 	char *fspec, *cs_disk, *cs_local;
196 	int error, len, *udf_flags;
197 	struct nameidata nd, *ndp = &nd;
198 
199 	td = curthread;
200 	opts = mp->mnt_optnew;
201 
202 	/*
203 	 * Unconditionally mount as read-only.
204 	 */
205 	MNT_ILOCK(mp);
206 	mp->mnt_flag |= MNT_RDONLY;
207 	MNT_IUNLOCK(mp);
208 
209 	/*
210 	 * No root filesystem support.  Probably not a big deal, since the
211 	 * bootloader doesn't understand UDF.
212 	 */
213 	if (mp->mnt_flag & MNT_ROOTFS)
214 		return (ENOTSUP);
215 
216 	fspec = NULL;
217 	error = vfs_getopt(opts, "from", (void **)&fspec, &len);
218 	if (!error && fspec[len - 1] != '\0')
219 		return (EINVAL);
220 
221 	if (mp->mnt_flag & MNT_UPDATE) {
222 		return (0);
223 	}
224 
225 	/* Check that the mount device exists */
226 	if (fspec == NULL)
227 		return (EINVAL);
228 	NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec, td);
229 	if ((error = namei(ndp)))
230 		return (error);
231 	NDFREE(ndp, NDF_ONLY_PNBUF);
232 	devvp = ndp->ni_vp;
233 
234 	if (vn_isdisk(devvp, &error) == 0) {
235 		vput(devvp);
236 		return (error);
237 	}
238 
239 	/* Check the access rights on the mount device */
240 	error = VOP_ACCESS(devvp, VREAD, td->td_ucred, td);
241 	if (error)
242 		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
243 	if (error) {
244 		vput(devvp);
245 		return (error);
246 	}
247 
248 	if ((error = udf_mountfs(devvp, mp))) {
249 		vrele(devvp);
250 		return (error);
251 	}
252 
253 	imp = VFSTOUDFFS(mp);
254 
255 	udf_flags = NULL;
256 	error = vfs_getopt(opts, "flags", (void **)&udf_flags, &len);
257 	if (error || len != sizeof(int))
258 		return (EINVAL);
259 	imp->im_flags = *udf_flags;
260 
261 	if (imp->im_flags & UDFMNT_KICONV && udf_iconv) {
262 		cs_disk = NULL;
263 		error = vfs_getopt(opts, "cs_disk", (void **)&cs_disk, &len);
264 		if (!error && cs_disk[len - 1] != '\0')
265 			return (EINVAL);
266 		cs_local = NULL;
267 		error = vfs_getopt(opts, "cs_local", (void **)&cs_local, &len);
268 		if (!error && cs_local[len - 1] != '\0')
269 			return (EINVAL);
270 		udf_iconv->open(cs_local, cs_disk, &imp->im_d2l);
271 #if 0
272 		udf_iconv->open(cs_disk, cs_local, &imp->im_l2d);
273 #endif
274 	}
275 
276 	vfs_mountedfrom(mp, fspec);
277 	return 0;
278 };
279 
280 /*
281  * Check the descriptor tag for both the correct id and correct checksum.
282  * Return zero if all is good, EINVAL if not.
283  */
284 int
285 udf_checktag(struct desc_tag *tag, uint16_t id)
286 {
287 	uint8_t *itag;
288 	uint8_t i, cksum = 0;
289 
290 	itag = (uint8_t *)tag;
291 
292 	if (le16toh(tag->id) != id)
293 		return (EINVAL);
294 
295 	for (i = 0; i < 16; i++)
296 		cksum = cksum + itag[i];
297 	cksum = cksum - itag[4];
298 
299 	if (cksum == tag->cksum)
300 		return (0);
301 
302 	return (EINVAL);
303 }
304 
305 static int
306 udf_mountfs(struct vnode *devvp, struct mount *mp)
307 {
308 	struct buf *bp = NULL;
309 	struct cdev *dev;
310 	struct anchor_vdp avdp;
311 	struct udf_mnt *udfmp = NULL;
312 	struct part_desc *pd;
313 	struct logvol_desc *lvd;
314 	struct fileset_desc *fsd;
315 	struct file_entry *root_fentry;
316 	uint32_t sector, size, mvds_start, mvds_end;
317 	uint32_t logical_secsize;
318 	uint32_t fsd_offset = 0;
319 	uint16_t part_num = 0, fsd_part = 0;
320 	int error = EINVAL;
321 	int logvol_found = 0, part_found = 0, fsd_found = 0;
322 	int bsize;
323 	struct g_consumer *cp;
324 	struct bufobj *bo;
325 
326 	dev = devvp->v_rdev;
327 	dev_ref(dev);
328 	DROP_GIANT();
329 	g_topology_lock();
330 	error = g_vfs_open(devvp, &cp, "udf", 0);
331 	g_topology_unlock();
332 	PICKUP_GIANT();
333 	VOP_UNLOCK(devvp, 0);
334 	if (error)
335 		goto bail;
336 
337 	bo = &devvp->v_bufobj;
338 
339 	if (devvp->v_rdev->si_iosize_max != 0)
340 		mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
341 	if (mp->mnt_iosize_max > MAXPHYS)
342 		mp->mnt_iosize_max = MAXPHYS;
343 
344 	/* XXX: should be M_WAITOK */
345 	udfmp = malloc(sizeof(struct udf_mnt), M_UDFMOUNT,
346 	    M_NOWAIT | M_ZERO);
347 	if (udfmp == NULL) {
348 		printf("Cannot allocate UDF mount struct\n");
349 		error = ENOMEM;
350 		goto bail;
351 	}
352 
353 	mp->mnt_data = udfmp;
354 	mp->mnt_stat.f_fsid.val[0] = dev2udev(devvp->v_rdev);
355 	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
356 	MNT_ILOCK(mp);
357 	mp->mnt_flag |= MNT_LOCAL;
358 	mp->mnt_kern_flag |= MNTK_MPSAFE | MNTK_LOOKUP_SHARED |
359 	    MNTK_EXTENDED_SHARED;
360 	MNT_IUNLOCK(mp);
361 	udfmp->im_mountp = mp;
362 	udfmp->im_dev = dev;
363 	udfmp->im_devvp = devvp;
364 	udfmp->im_d2l = NULL;
365 	udfmp->im_cp = cp;
366 	udfmp->im_bo = bo;
367 
368 #if 0
369 	udfmp->im_l2d = NULL;
370 #endif
371 	/*
372 	 * The UDF specification defines a logical sectorsize of 2048
373 	 * for DVD media.
374 	 */
375 	logical_secsize = 2048;
376 
377 	if (((logical_secsize % cp->provider->sectorsize) != 0) ||
378 	    (logical_secsize < cp->provider->sectorsize)) {
379 		error = EINVAL;
380 		goto bail;
381 	}
382 
383 	bsize = cp->provider->sectorsize;
384 
385 	/*
386 	 * Get the Anchor Volume Descriptor Pointer from sector 256.
387 	 * XXX Should also check sector n - 256, n, and 512.
388 	 */
389 	sector = 256;
390 	if ((error = bread(devvp, sector * btodb(logical_secsize), bsize,
391 			   NOCRED, &bp)) != 0)
392 		goto bail;
393 	if ((error = udf_checktag((struct desc_tag *)bp->b_data, TAGID_ANCHOR)))
394 		goto bail;
395 
396 	bcopy(bp->b_data, &avdp, sizeof(struct anchor_vdp));
397 	brelse(bp);
398 	bp = NULL;
399 
400 	/*
401 	 * Extract the Partition Descriptor and Logical Volume Descriptor
402 	 * from the Volume Descriptor Sequence.
403 	 * XXX Should we care about the partition type right now?
404 	 * XXX What about multiple partitions?
405 	 */
406 	mvds_start = le32toh(avdp.main_vds_ex.loc);
407 	mvds_end = mvds_start + (le32toh(avdp.main_vds_ex.len) - 1) / bsize;
408 	for (sector = mvds_start; sector < mvds_end; sector++) {
409 		if ((error = bread(devvp, sector * btodb(logical_secsize),
410 				   bsize, NOCRED, &bp)) != 0) {
411 			printf("Can't read sector %d of VDS\n", sector);
412 			goto bail;
413 		}
414 		lvd = (struct logvol_desc *)bp->b_data;
415 		if (!udf_checktag(&lvd->tag, TAGID_LOGVOL)) {
416 			udfmp->bsize = le32toh(lvd->lb_size);
417 			udfmp->bmask = udfmp->bsize - 1;
418 			udfmp->bshift = ffs(udfmp->bsize) - 1;
419 			fsd_part = le16toh(lvd->_lvd_use.fsd_loc.loc.part_num);
420 			fsd_offset = le32toh(lvd->_lvd_use.fsd_loc.loc.lb_num);
421 			if (udf_find_partmaps(udfmp, lvd))
422 				break;
423 			logvol_found = 1;
424 		}
425 		pd = (struct part_desc *)bp->b_data;
426 		if (!udf_checktag(&pd->tag, TAGID_PARTITION)) {
427 			part_found = 1;
428 			part_num = le16toh(pd->part_num);
429 			udfmp->part_len = le32toh(pd->part_len);
430 			udfmp->part_start = le32toh(pd->start_loc);
431 		}
432 
433 		brelse(bp);
434 		bp = NULL;
435 		if ((part_found) && (logvol_found))
436 			break;
437 	}
438 
439 	if (!part_found || !logvol_found) {
440 		error = EINVAL;
441 		goto bail;
442 	}
443 
444 	if (fsd_part != part_num) {
445 		printf("FSD does not lie within the partition!\n");
446 		error = EINVAL;
447 		goto bail;
448 	}
449 
450 
451 	/*
452 	 * Grab the Fileset Descriptor
453 	 * Thanks to Chuck McCrobie <mccrobie@cablespeed.com> for pointing
454 	 * me in the right direction here.
455 	 */
456 	sector = udfmp->part_start + fsd_offset;
457 	if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
458 		printf("Cannot read sector %d of FSD\n", sector);
459 		goto bail;
460 	}
461 	fsd = (struct fileset_desc *)bp->b_data;
462 	if (!udf_checktag(&fsd->tag, TAGID_FSD)) {
463 		fsd_found = 1;
464 		bcopy(&fsd->rootdir_icb, &udfmp->root_icb,
465 		    sizeof(struct long_ad));
466 	}
467 
468 	brelse(bp);
469 	bp = NULL;
470 
471 	if (!fsd_found) {
472 		printf("Couldn't find the fsd\n");
473 		error = EINVAL;
474 		goto bail;
475 	}
476 
477 	/*
478 	 * Find the file entry for the root directory.
479 	 */
480 	sector = le32toh(udfmp->root_icb.loc.lb_num) + udfmp->part_start;
481 	size = le32toh(udfmp->root_icb.len);
482 	if ((error = udf_readdevblks(udfmp, sector, size, &bp)) != 0) {
483 		printf("Cannot read sector %d\n", sector);
484 		goto bail;
485 	}
486 
487 	root_fentry = (struct file_entry *)bp->b_data;
488 	if ((error = udf_checktag(&root_fentry->tag, TAGID_FENTRY))) {
489 		printf("Invalid root file entry!\n");
490 		goto bail;
491 	}
492 
493 	brelse(bp);
494 	bp = NULL;
495 
496 	return 0;
497 
498 bail:
499 	if (udfmp != NULL)
500 		free(udfmp, M_UDFMOUNT);
501 	if (bp != NULL)
502 		brelse(bp);
503 	if (cp != NULL) {
504 		DROP_GIANT();
505 		g_topology_lock();
506 		g_vfs_close(cp);
507 		g_topology_unlock();
508 		PICKUP_GIANT();
509 	}
510 	dev_rel(dev);
511 	return error;
512 };
513 
514 static int
515 udf_unmount(struct mount *mp, int mntflags)
516 {
517 	struct udf_mnt *udfmp;
518 	int error, flags = 0;
519 
520 	udfmp = VFSTOUDFFS(mp);
521 
522 	if (mntflags & MNT_FORCE)
523 		flags |= FORCECLOSE;
524 
525 	if ((error = vflush(mp, 0, flags, curthread)))
526 		return (error);
527 
528 	if (udfmp->im_flags & UDFMNT_KICONV && udf_iconv) {
529 		if (udfmp->im_d2l)
530 			udf_iconv->close(udfmp->im_d2l);
531 #if 0
532 		if (udfmp->im_l2d)
533 			udf_iconv->close(udfmp->im_l2d);
534 #endif
535 	}
536 
537 	DROP_GIANT();
538 	g_topology_lock();
539 	g_vfs_close(udfmp->im_cp);
540 	g_topology_unlock();
541 	PICKUP_GIANT();
542 	vrele(udfmp->im_devvp);
543 	dev_rel(udfmp->im_dev);
544 
545 	if (udfmp->s_table != NULL)
546 		free(udfmp->s_table, M_UDFMOUNT);
547 
548 	free(udfmp, M_UDFMOUNT);
549 
550 	mp->mnt_data = NULL;
551 	MNT_ILOCK(mp);
552 	mp->mnt_flag &= ~MNT_LOCAL;
553 	MNT_IUNLOCK(mp);
554 
555 	return (0);
556 }
557 
558 static int
559 udf_root(struct mount *mp, int flags, struct vnode **vpp)
560 {
561 	struct udf_mnt *udfmp;
562 	ino_t id;
563 
564 	udfmp = VFSTOUDFFS(mp);
565 
566 	id = udf_getid(&udfmp->root_icb);
567 
568 	return (udf_vget(mp, id, flags, vpp));
569 }
570 
571 static int
572 udf_statfs(struct mount *mp, struct statfs *sbp)
573 {
574 	struct udf_mnt *udfmp;
575 
576 	udfmp = VFSTOUDFFS(mp);
577 
578 	sbp->f_bsize = udfmp->bsize;
579 	sbp->f_iosize = udfmp->bsize;
580 	sbp->f_blocks = udfmp->part_len;
581 	sbp->f_bfree = 0;
582 	sbp->f_bavail = 0;
583 	sbp->f_files = 0;
584 	sbp->f_ffree = 0;
585 	return 0;
586 }
587 
588 int
589 udf_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
590 {
591 	struct buf *bp;
592 	struct vnode *devvp;
593 	struct udf_mnt *udfmp;
594 	struct thread *td;
595 	struct vnode *vp;
596 	struct udf_node *unode;
597 	struct file_entry *fe;
598 	int error, sector, size;
599 
600 	error = vfs_hash_get(mp, ino, flags, curthread, vpp, NULL, NULL);
601 	if (error || *vpp != NULL)
602 		return (error);
603 
604 	/*
605 	 * We must promote to an exclusive lock for vnode creation.  This
606 	 * can happen if lookup is passed LOCKSHARED.
607  	 */
608 	if ((flags & LK_TYPE_MASK) == LK_SHARED) {
609 		flags &= ~LK_TYPE_MASK;
610 		flags |= LK_EXCLUSIVE;
611 	}
612 
613 	/*
614 	 * We do not lock vnode creation as it is believed to be too
615 	 * expensive for such rare case as simultaneous creation of vnode
616 	 * for same ino by different processes. We just allow them to race
617 	 * and check later to decide who wins. Let the race begin!
618 	 */
619 
620 	td = curthread;
621 	udfmp = VFSTOUDFFS(mp);
622 
623 	unode = uma_zalloc(udf_zone_node, M_WAITOK | M_ZERO);
624 
625 	if ((error = udf_allocv(mp, &vp, td))) {
626 		printf("Error from udf_allocv\n");
627 		uma_zfree(udf_zone_node, unode);
628 		return (error);
629 	}
630 
631 	unode->i_vnode = vp;
632 	unode->hash_id = ino;
633 	unode->udfmp = udfmp;
634 	vp->v_data = unode;
635 
636 	lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
637 	error = insmntque(vp, mp);
638 	if (error != 0) {
639 		uma_zfree(udf_zone_node, unode);
640 		return (error);
641 	}
642 	error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
643 	if (error || *vpp != NULL)
644 		return (error);
645 
646 	/*
647 	 * Copy in the file entry.  Per the spec, the size can only be 1 block.
648 	 */
649 	sector = ino + udfmp->part_start;
650 	devvp = udfmp->im_devvp;
651 	if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
652 		printf("Cannot read sector %d\n", sector);
653 		vgone(vp);
654 		vput(vp);
655 		brelse(bp);
656 		*vpp = NULL;
657 		return (error);
658 	}
659 
660 	fe = (struct file_entry *)bp->b_data;
661 	if (udf_checktag(&fe->tag, TAGID_FENTRY)) {
662 		printf("Invalid file entry!\n");
663 		vgone(vp);
664 		vput(vp);
665 		brelse(bp);
666 		*vpp = NULL;
667 		return (ENOMEM);
668 	}
669 	size = UDF_FENTRY_SIZE + le32toh(fe->l_ea) + le32toh(fe->l_ad);
670 	unode->fentry = malloc(size, M_UDFFENTRY, M_NOWAIT | M_ZERO);
671 	if (unode->fentry == NULL) {
672 		printf("Cannot allocate file entry block\n");
673 		vgone(vp);
674 		vput(vp);
675 		brelse(bp);
676 		*vpp = NULL;
677 		return (ENOMEM);
678 	}
679 
680 	bcopy(bp->b_data, unode->fentry, size);
681 
682 	brelse(bp);
683 	bp = NULL;
684 
685 	switch (unode->fentry->icbtag.file_type) {
686 	default:
687 		vp->v_type = VBAD;
688 		break;
689 	case 4:
690 		vp->v_type = VDIR;
691 		break;
692 	case 5:
693 		vp->v_type = VREG;
694 		break;
695 	case 6:
696 		vp->v_type = VBLK;
697 		break;
698 	case 7:
699 		vp->v_type = VCHR;
700 		break;
701 	case 9:
702 		vp->v_type = VFIFO;
703 		vp->v_op = &udf_fifoops;
704 		break;
705 	case 10:
706 		vp->v_type = VSOCK;
707 		break;
708 	case 12:
709 		vp->v_type = VLNK;
710 		break;
711 	}
712 
713 	if (vp->v_type != VFIFO)
714 		VN_LOCK_ASHARE(vp);
715 
716 	if (ino == udf_getid(&udfmp->root_icb))
717 		vp->v_vflag |= VV_ROOT;
718 
719 	*vpp = vp;
720 
721 	return (0);
722 }
723 
724 static int
725 udf_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
726 {
727 	struct ifid *ifhp;
728 	struct vnode *nvp;
729 	struct udf_node *np;
730 	off_t fsize;
731 	int error;
732 
733 	ifhp = (struct ifid *)fhp;
734 
735 	if ((error = VFS_VGET(mp, ifhp->ifid_ino, LK_EXCLUSIVE, &nvp)) != 0) {
736 		*vpp = NULLVP;
737 		return (error);
738 	}
739 
740 	np = VTON(nvp);
741 	fsize = le64toh(np->fentry->inf_len);
742 
743 	*vpp = nvp;
744 	vnode_create_vobject(*vpp, fsize, curthread);
745 	return (0);
746 }
747 
748 static int
749 udf_find_partmaps(struct udf_mnt *udfmp, struct logvol_desc *lvd)
750 {
751 	struct part_map_spare *pms;
752 	struct regid *pmap_id;
753 	struct buf *bp;
754 	unsigned char regid_id[UDF_REGID_ID_SIZE + 1];
755 	int i, k, ptype, psize, error;
756 	uint8_t *pmap = (uint8_t *) &lvd->maps[0];
757 
758 	for (i = 0; i < le32toh(lvd->n_pm); i++) {
759 		ptype = pmap[0];
760 		psize = pmap[1];
761 		if (((ptype != 1) && (ptype != 2)) ||
762 		    ((psize != UDF_PMAP_TYPE1_SIZE) &&
763 		     (psize != UDF_PMAP_TYPE2_SIZE))) {
764 			printf("Invalid partition map found\n");
765 			return (1);
766 		}
767 
768 		if (ptype == 1) {
769 			/* Type 1 map.  We don't care */
770 			pmap += UDF_PMAP_TYPE1_SIZE;
771 			continue;
772 		}
773 
774 		/* Type 2 map.  Gotta find out the details */
775 		pmap_id = (struct regid *)&pmap[4];
776 		bzero(&regid_id[0], UDF_REGID_ID_SIZE);
777 		bcopy(&pmap_id->id[0], &regid_id[0], UDF_REGID_ID_SIZE);
778 
779 		if (bcmp(&regid_id[0], "*UDF Sparable Partition",
780 		    UDF_REGID_ID_SIZE)) {
781 			printf("Unsupported partition map: %s\n", &regid_id[0]);
782 			return (1);
783 		}
784 
785 		pms = (struct part_map_spare *)pmap;
786 		pmap += UDF_PMAP_TYPE2_SIZE;
787 		udfmp->s_table = malloc(le32toh(pms->st_size),
788 		    M_UDFMOUNT, M_NOWAIT | M_ZERO);
789 		if (udfmp->s_table == NULL)
790 			return (ENOMEM);
791 
792 		/* Calculate the number of sectors per packet. */
793 		/* XXX Logical or physical? */
794 		udfmp->p_sectors = le16toh(pms->packet_len) / udfmp->bsize;
795 
796 		/*
797 		 * XXX If reading the first Sparing Table fails, should look
798 		 * for another table.
799 		 */
800 		if ((error = udf_readdevblks(udfmp, le32toh(pms->st_loc[0]),
801 					   le32toh(pms->st_size), &bp)) != 0) {
802 			if (bp != NULL)
803 				brelse(bp);
804 			printf("Failed to read Sparing Table at sector %d\n",
805 			    le32toh(pms->st_loc[0]));
806 			free(udfmp->s_table, M_UDFMOUNT);
807 			return (error);
808 		}
809 		bcopy(bp->b_data, udfmp->s_table, le32toh(pms->st_size));
810 		brelse(bp);
811 
812 		if (udf_checktag(&udfmp->s_table->tag, 0)) {
813 			printf("Invalid sparing table found\n");
814 			free(udfmp->s_table, M_UDFMOUNT);
815 			return (EINVAL);
816 		}
817 
818 		/* See how many valid entries there are here.  The list is
819 		 * supposed to be sorted. 0xfffffff0 and higher are not valid
820 		 */
821 		for (k = 0; k < le16toh(udfmp->s_table->rt_l); k++) {
822 			udfmp->s_table_entries = k;
823 			if (le32toh(udfmp->s_table->entries[k].org) >=
824 			    0xfffffff0)
825 				break;
826 		}
827 	}
828 
829 	return (0);
830 }
831