xref: /dragonfly/sys/vfs/udf/udf_vfsops.c (revision 73e0051e)
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: src/sys/fs/udf/udf_vfsops.c,v 1.16 2003/11/05 06:56:08 scottl Exp $
27  * $DragonFly: src/sys/vfs/udf/udf_vfsops.c,v 1.28 2008/09/17 21:44:25 dillon Exp $
28  */
29 
30 /* udf_vfsops.c */
31 /* Implement the VFS side of things */
32 
33 /*
34  * Ok, here's how it goes.  The UDF specs are pretty clear on how each data
35  * structure is made up, but not very clear on how they relate to each other.
36  * Here is the skinny... This demostrates a filesystem with one file in the
37  * root directory.  Subdirectories are treated just as normal files, but they
38  * have File Id Descriptors of their children as their file data.  As for the
39  * Anchor Volume Descriptor Pointer, it can exist in two of the following three
40  * places: sector 256, sector n (the max sector of the disk), or sector
41  * n - 256.  It's a pretty good bet that one will exist at sector 256 though.
42  * One caveat is unclosed CD media.  For that, sector 256 cannot be written,
43  * so the Anchor Volume Descriptor Pointer can exist at sector 512 until the
44  * media is closed.
45  *
46  *  Sector:
47  *     256:
48  *       n: Anchor Volume Descriptor Pointer
49  * n - 256:	|
50  *		|
51  *		|-->Main Volume Descriptor Sequence
52  *			|	|
53  *			|	|
54  *			|	|-->Logical Volume Descriptor
55  *			|			  |
56  *			|-->Partition Descriptor  |
57  *				|		  |
58  *				|		  |
59  *				|-->Fileset Descriptor
60  *					|
61  *					|
62  *					|-->Root Dir File Entry
63  *						|
64  *						|
65  *						|-->File data:
66  *						    File Id Descriptor
67  *							|
68  *							|
69  *							|-->File Entry
70  *								|
71  *								|
72  *								|-->File data
73  */
74 
75 #include <sys/types.h>
76 #include <sys/param.h>
77 #include <sys/systm.h>
78 #include <sys/uio.h>
79 #include <sys/buf.h>
80 #include <sys/conf.h>
81 #include <sys/fcntl.h>
82 #include <sys/module.h>
83 #include <sys/kernel.h>
84 #include <sys/malloc.h>
85 #include <sys/mount.h>
86 #include <sys/nlookup.h>
87 #include <sys/proc.h>
88 #include <sys/priv.h>
89 #include <sys/queue.h>
90 #include <sys/vnode.h>
91 
92 #include <vfs/udf/ecma167-udf.h>
93 #include <vfs/udf/osta.h>
94 #include <vfs/udf/udf.h>
95 #include <vfs/udf/udf_mount.h>
96 
97 extern struct vop_ops udf_vnode_vops;
98 
99 MALLOC_DEFINE(M_UDFNODE, "UDF node", "UDF node structure");
100 MALLOC_DEFINE(M_UDFMOUNT, "UDF mount", "UDF mount structure");
101 MALLOC_DEFINE(M_UDFFENTRY, "UDF fentry", "UDF file entry structure");
102 
103 static int udf_mount(struct mount *, char *, caddr_t, struct ucred *);
104 static int udf_unmount(struct mount *, int);
105 static int udf_root(struct mount *, struct vnode **);
106 static int udf_statfs(struct mount *, struct statfs *, struct ucred *);
107 static int udf_fhtovp(struct mount *, struct vnode *,
108 				struct fid *, struct vnode **);
109 static int udf_vptofh(struct vnode *, struct fid *);
110 
111 static int udf_find_partmaps(struct udf_mnt *, struct logvol_desc *);
112 
113 static struct vfsops udf_vfsops = {
114 	.vfs_mount =    	udf_mount,
115 	.vfs_unmount =    	udf_unmount,
116 	.vfs_root =    		udf_root,
117 	.vfs_statfs =    	udf_statfs,
118 	.vfs_sync =    		vfs_stdsync,
119 	.vfs_vget =    		udf_vget,
120 	.vfs_fhtovp =    	udf_fhtovp,
121 	.vfs_vptofh =    	udf_vptofh
122 };
123 VFS_SET(udf_vfsops, udf, VFCF_READONLY);
124 
125 MODULE_VERSION(udf, 1);
126 
127 static int udf_mountfs(struct vnode *, struct mount *);
128 
129 static int
130 udf_mount(struct mount *mp, char *path, caddr_t data, struct ucred *cred)
131 {
132 	struct vnode *devvp;	/* vnode of the mount device */
133 	struct udf_args args;
134 	struct udf_mnt *imp = 0;
135 	size_t size;
136 	int error;
137 	struct nlookupdata nd;
138 
139 	if ((mp->mnt_flag & MNT_RDONLY) == 0)
140 		return (EROFS);
141 
142 	/*
143 	 * No root filesystem support.  Probably not a big deal, since the
144 	 * bootloader doesn't understand UDF.
145 	 */
146 	if (mp->mnt_flag & MNT_ROOTFS)
147 		return (ENOTSUP);
148 
149 	if ((error = copyin(data, (caddr_t)&args, sizeof(struct udf_args))))
150 		return(error);
151 
152 	if (mp->mnt_flag & MNT_UPDATE) {
153 		imp = VFSTOUDFFS(mp);
154 		if (args.fspec == NULL)
155 			return(vfs_export(mp, &imp->im_export, &args.export));
156 	}
157 
158 	/* Check that the mount device exists */
159 	devvp = NULL;
160 	error = nlookup_init(&nd, args.fspec, UIO_USERSPACE, NLC_FOLLOW);
161 	if (error == 0)
162 		error = nlookup(&nd);
163 	if (error == 0)
164 		error = cache_vref(&nd.nl_nch, nd.nl_cred, &devvp);
165 	nlookup_done(&nd);
166 	if (error)
167 		return (error);
168 
169 	if (vn_isdisk(devvp, &error) == 0) {
170 		vrele(devvp);
171 		return(error);
172 	}
173 
174 	/* Check the access rights on the mount device */
175 	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
176 	error = VOP_EACCESS(devvp, VREAD, cred);
177 	if (error)
178 		error = priv_check_cred(cred, PRIV_ROOT, 0);
179 	if (error) {
180 		vput(devvp);
181 		return(error);
182 	}
183 	vn_unlock(devvp);
184 
185 	if ((error = udf_mountfs(devvp, mp))) {
186 		vrele(devvp);
187 		return(error);
188 	}
189 
190 	imp = VFSTOUDFFS(mp);
191 
192 	imp->im_flags = args.flags;
193 
194 	copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, &size);
195 	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
196 	udf_statfs(mp, &mp->mnt_stat, cred);
197 	return(0);
198 }
199 
200 /*
201  * Check the descriptor tag for both the correct id and correct checksum.
202  * Return zero if all is good, EINVAL if not.
203  */
204 int
205 udf_checktag(struct desc_tag *tag, uint16_t id)
206 {
207 	uint8_t *itag;
208 	uint8_t i, cksum = 0;
209 
210 	itag = (uint8_t *)tag;
211 
212 	if (tag->id != id)
213 		return(EINVAL);
214 
215 	for (i = 0; i < 15; i++)
216 		cksum = cksum + itag[i];
217 	cksum = cksum - itag[4];
218 
219 	if (cksum == tag->cksum)
220 		return(0);
221 
222 	return(EINVAL);
223 }
224 
225 static int
226 udf_mountfs(struct vnode *devvp, struct mount *mp)
227 {
228 	struct buf *bp = NULL;
229 	struct anchor_vdp avdp;
230 	struct udf_mnt *udfmp = NULL;
231 	struct part_desc *pd;
232 	struct logvol_desc *lvd;
233 	struct fileset_desc *fsd;
234 	struct file_entry *root_fentry;
235 	cdev_t dev;
236 	uint32_t sector, size, mvds_start, mvds_end;
237 	uint32_t fsd_offset = 0;
238 	uint16_t part_num = 0, fsd_part = 0;
239 	int error = EINVAL, needclose = 0;
240 	int logvol_found = 0, part_found = 0, fsd_found = 0;
241 	int bsize;
242 
243 	/*
244 	 * Disallow multiple mounts of the same device. Flush the buffer
245 	 * cache for the device.
246 	 */
247 	if ((error = vfs_mountedon(devvp)))
248 		return(error);
249 	if (vcount(devvp) > 0)
250 		return(EBUSY);
251 	if ((error = vinvalbuf(devvp, V_SAVE, 0, 0)))
252 		return(error);
253 
254 	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
255 	error = VOP_OPEN(devvp, FREAD, FSCRED, NULL);
256 	vn_unlock(devvp);
257 	if (error)
258 		return(error);
259 	needclose = 1;
260 	dev = devvp->v_rdev;
261 
262 	udfmp = kmalloc(sizeof(*udfmp), M_UDFMOUNT, M_WAITOK | M_ZERO);
263 
264 	mp->mnt_data = (qaddr_t)udfmp;
265 	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
266 	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
267 	mp->mnt_maxsymlinklen = 0;
268 	mp->mnt_flag |= MNT_LOCAL;
269 	udfmp->im_mountp = mp;
270 	udfmp->im_dev = dev;
271 	udfmp->im_devvp = devvp;
272 
273 	bsize = 2048;	/* XXX Should probe the media for it's size */
274 
275 	/*
276 	 * Get the Anchor Volume Descriptor Pointer from sector 256.
277 	 * XXX Should also check sector n - 256, n, and 512.
278 	 */
279 	sector = 256;
280 	if ((error = bread(devvp, (off_t)sector * bsize, bsize, &bp)) != 0)
281 		goto bail;
282 	if ((error = udf_checktag((struct desc_tag *)bp->b_data, TAGID_ANCHOR)))
283 		goto bail;
284 
285 	bcopy(bp->b_data, &avdp, sizeof(struct anchor_vdp));
286 	brelse(bp);
287 	bp = NULL;
288 
289 	/*
290 	 * Extract the Partition Descriptor and Logical Volume Descriptor
291 	 * from the Volume Descriptor Sequence.
292 	 * XXX Should we care about the partition type right now?
293 	 * XXX What about multiple partitions?
294 	 */
295 	mvds_start = avdp.main_vds_ex.loc;
296 	mvds_end = mvds_start + (avdp.main_vds_ex.len - 1) / bsize;
297 	for (sector = mvds_start; sector < mvds_end; sector++) {
298 		if ((error = bread(devvp, (off_t)sector * bsize, bsize,
299 				   &bp)) != 0) {
300 			kprintf("Can't read sector %d of VDS\n", sector);
301 			goto bail;
302 		}
303 		lvd = (struct logvol_desc *)bp->b_data;
304 		if (!udf_checktag(&lvd->tag, TAGID_LOGVOL)) {
305 			udfmp->bsize = lvd->lb_size;
306 			udfmp->bmask = udfmp->bsize - 1;
307 			udfmp->bshift = ffs(udfmp->bsize) - 1;
308 			fsd_part = lvd->_lvd_use.fsd_loc.loc.part_num;
309 			fsd_offset = lvd->_lvd_use.fsd_loc.loc.lb_num;
310 			if (udf_find_partmaps(udfmp, lvd))
311 				break;
312 			logvol_found = 1;
313 		}
314 		pd = (struct part_desc *)bp->b_data;
315 		if (!udf_checktag(&pd->tag, TAGID_PARTITION)) {
316 			part_found = 1;
317 			part_num = pd->part_num;
318 			udfmp->part_len = pd->part_len;
319 			udfmp->part_start = pd->start_loc;
320 		}
321 
322 		brelse(bp);
323 		bp = NULL;
324 		if ((part_found) && (logvol_found))
325 			break;
326 	}
327 
328 	if (!part_found || !logvol_found) {
329 		error = EINVAL;
330 		goto bail;
331 	}
332 
333 	if (fsd_part != part_num) {
334 		kprintf("FSD does not lie within the partition!\n");
335 		error = EINVAL;
336 		goto bail;
337 	}
338 
339 
340 	/*
341 	 * Grab the Fileset Descriptor
342 	 * Thanks to Chuck McCrobie <mccrobie@cablespeed.com> for pointing
343 	 * me in the right direction here.
344 	 */
345 	sector = udfmp->part_start + fsd_offset;
346 	if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
347 		kprintf("Cannot read sector %d of FSD\n", sector);
348 		goto bail;
349 	}
350 	fsd = (struct fileset_desc *)bp->b_data;
351 	if (!udf_checktag(&fsd->tag, TAGID_FSD)) {
352 		fsd_found = 1;
353 		bcopy(&fsd->rootdir_icb, &udfmp->root_icb,
354 		      sizeof(struct long_ad));
355 	}
356 
357 	brelse(bp);
358 	bp = NULL;
359 
360 	if (!fsd_found) {
361 		kprintf("Couldn't find the fsd\n");
362 		error = EINVAL;
363 		goto bail;
364 	}
365 
366 	vfs_add_vnodeops(mp, &udf_vnode_vops, &mp->mnt_vn_norm_ops);
367 
368 	/*
369 	 * Find the file entry for the root directory.
370 	 */
371 	sector = udfmp->root_icb.loc.lb_num + udfmp->part_start;
372 	size = udfmp->root_icb.len;
373 	if ((error = udf_readlblks(udfmp, sector, size, &bp)) != 0) {
374 		kprintf("Cannot read sector %d\n", sector);
375 		goto bail;
376 	}
377 
378 	root_fentry = (struct file_entry *)bp->b_data;
379 	if ((error = udf_checktag(&root_fentry->tag, TAGID_FENTRY))) {
380 		kprintf("Invalid root file entry!\n");
381 		goto bail;
382 	}
383 
384 	brelse(bp);
385 	bp = NULL;
386 
387 	lwkt_token_init(&udfmp->hash_token);
388 	udfmp->hashtbl = phashinit(UDF_HASHTBLSIZE, M_UDFMOUNT, &udfmp->hashsz);
389 
390 	return(0);
391 
392 bail:
393 	if (udfmp != NULL)
394 		kfree(udfmp, M_UDFMOUNT);
395 	if (bp != NULL)
396 		brelse(bp);
397 	if (needclose)
398 		VOP_CLOSE(devvp, FREAD);
399 	return(error);
400 }
401 
402 static int
403 udf_unmount(struct mount *mp, int mntflags)
404 {
405 	struct udf_mnt *udfmp;
406 	int error, flags = 0;
407 
408 	udfmp = VFSTOUDFFS(mp);
409 
410 	if (mntflags & MNT_FORCE)
411 		flags |= FORCECLOSE;
412 
413 	if ((error = vflush(mp, 0, flags)))
414 		return (error);
415 
416 	udfmp->im_devvp->v_rdev->si_mountpoint = NULL;
417 	error = VOP_CLOSE(udfmp->im_devvp, FREAD);
418 	vrele(udfmp->im_devvp);
419 
420 	if (udfmp->s_table)
421 		kfree(udfmp->s_table, M_UDFMOUNT);
422 	if (udfmp->hashtbl)
423 		kfree(udfmp->hashtbl, M_UDFMOUNT);
424 	kfree(udfmp, M_UDFMOUNT);
425 
426 	mp->mnt_data = (qaddr_t)0;
427 	mp->mnt_flag &= ~MNT_LOCAL;
428 
429 	return (error);
430 }
431 
432 static int
433 udf_root(struct mount *mp, struct vnode **vpp)
434 {
435 	struct udf_mnt *udfmp;
436 	struct vnode *vp;
437 	ino_t id;
438 	int error;
439 
440 	udfmp = VFSTOUDFFS(mp);
441 
442 	id = udf_getid(&udfmp->root_icb);
443 
444 	error = udf_vget(mp, NULL, id, vpp);
445 	if (error)
446 		return(error);
447 
448 	vp = *vpp;
449 	vp->v_flag |= VROOT;
450 	udfmp->root_vp = vp;
451 
452 	return(0);
453 }
454 
455 static int
456 udf_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
457 {
458 	struct udf_mnt *udfmp;
459 
460 	udfmp = VFSTOUDFFS(mp);
461 
462 	sbp->f_bsize = udfmp->bsize;
463 	sbp->f_iosize = udfmp->bsize;
464 	sbp->f_blocks = udfmp->part_len;
465 	sbp->f_bfree = 0;
466 	sbp->f_bavail = 0;
467 	sbp->f_files = 0;
468 	sbp->f_ffree = 0;
469 	if (sbp != &mp->mnt_stat) {
470 		sbp->f_type = mp->mnt_vfc->vfc_typenum;
471 		bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
472 	}
473 
474 	return(0);
475 }
476 
477 int
478 udf_vget(struct mount *mp, struct vnode *dvp, ino_t ino, struct vnode **vpp)
479 {
480 	struct buf *bp;
481 	struct vnode *devvp;
482 	struct udf_mnt *udfmp;
483 	struct thread *td;
484 	struct vnode *vp;
485 	struct udf_node *unode;
486 	struct file_entry *fe;
487 	int error, sector, size;
488 
489 	td = curthread;
490 	udfmp = VFSTOUDFFS(mp);
491 
492 	/* See if we already have this in the cache */
493 	if ((error = udf_hashlookup(udfmp, ino, vpp)) != 0)
494 		return(error);
495 	if (*vpp != NULL) {
496 		return(0);
497 	}
498 
499 	/*
500 	 * Allocate memory and check the tag id's before grabbing a new
501 	 * vnode, since it's hard to roll back if there is a problem.
502 	 */
503 	unode = kmalloc(sizeof(*unode), M_UDFNODE, M_WAITOK | M_ZERO);
504 
505 	/*
506 	 * Copy in the file entry.  Per the spec, the size can only be 1 block.
507 	 */
508 	sector = ino + udfmp->part_start;
509 	devvp = udfmp->im_devvp;
510 	if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
511 		kprintf("Cannot read sector %d\n", sector);
512 		kfree(unode, M_UDFNODE);
513 		return(error);
514 	}
515 
516 	fe = (struct file_entry *)bp->b_data;
517 	if (udf_checktag(&fe->tag, TAGID_FENTRY)) {
518 		kprintf("Invalid file entry!\n");
519 		kfree(unode, M_UDFNODE);
520 		brelse(bp);
521 		return(ENOMEM);
522 	}
523 	size = UDF_FENTRY_SIZE + fe->l_ea + fe->l_ad;
524 	unode->fentry = kmalloc(size, M_UDFFENTRY, M_WAITOK | M_ZERO);
525 
526 	bcopy(bp->b_data, unode->fentry, size);
527 
528 	brelse(bp);
529 	bp = NULL;
530 
531 	if ((error = udf_allocv(mp, &vp))) {
532 		kprintf("Error from udf_allocv\n");
533 		kfree(unode, M_UDFNODE);
534 		return(error);
535 	}
536 
537 	unode->i_vnode = vp;
538 	unode->hash_id = ino;
539 	unode->i_devvp = udfmp->im_devvp;
540 	unode->i_dev = udfmp->im_dev;
541 	unode->udfmp = udfmp;
542 	vp->v_data = unode;
543 	vref(udfmp->im_devvp);
544 	udf_hashins(unode);
545 
546 	switch (unode->fentry->icbtag.file_type) {
547 	default:
548 		vp->v_type = VBAD;
549 		break;
550 	case 4:
551 		vp->v_type = VDIR;
552 		break;
553 	case 5:
554 		vp->v_type = VREG;
555 		break;
556 	case 6:
557 		vp->v_type = VBLK;
558 		break;
559 	case 7:
560 		vp->v_type = VCHR;
561 		break;
562 	case 9:
563 		vp->v_type = VFIFO;
564 		break;
565 	case 10:
566 		vp->v_type = VSOCK;
567 		break;
568 	case 12:
569 		vp->v_type = VLNK;
570 		break;
571 	}
572 	/*
573 	 * Locked and refd vnode returned
574 	 */
575 	*vpp = vp;
576 
577 	return(0);
578 }
579 
580 struct ifid {
581 	u_short	ifid_len;
582 	u_short	ifid_pad;
583 	int	ifid_ino;
584 	long	ifid_start;
585 };
586 
587 static int
588 udf_fhtovp(struct mount *mp, struct vnode *rootvp,
589 	   struct fid *fhp, struct vnode **vpp)
590 {
591 	struct ifid *ifhp;
592 	struct vnode *nvp;
593 	int error;
594 
595 	ifhp = (struct ifid *)fhp;
596 
597 	if ((error = VFS_VGET(mp, NULL, ifhp->ifid_ino, &nvp)) != 0) {
598 		*vpp = NULLVP;
599 		return(error);
600 	}
601 
602 	*vpp = nvp;
603 	return(0);
604 }
605 
606 static int
607 udf_vptofh (struct vnode *vp, struct fid *fhp)
608 {
609 	struct udf_node *node;
610 	struct ifid *ifhp;
611 
612 	node = VTON(vp);
613 	ifhp = (struct ifid *)fhp;
614 	ifhp->ifid_len = sizeof(struct ifid);
615 	ifhp->ifid_ino = node->hash_id;
616 
617 	return(0);
618 }
619 
620 static int
621 udf_find_partmaps(struct udf_mnt *udfmp, struct logvol_desc *lvd)
622 {
623 	union udf_pmap *pmap;
624 	struct part_map_spare *pms;
625 	struct regid *pmap_id;
626 	struct buf *bp;
627 	unsigned char regid_id[UDF_REGID_ID_SIZE + 1];
628 	int ptype, psize, error;
629 	unsigned int i;
630 
631 	for (i = 0; i < lvd->n_pm; i++) {
632 		pmap = (union udf_pmap *)&lvd->maps[i * UDF_PMAP_SIZE];
633 		ptype = pmap->data[0];
634 		psize = pmap->data[1];
635 		if (((ptype != 1) && (ptype != 2)) ||
636 		    ((psize != UDF_PMAP_SIZE) && (psize != 6))) {
637 			kprintf("Invalid partition map found\n");
638 			return(1);
639 		}
640 
641 		if (ptype == 1) {
642 			/* Type 1 map.  We don't care */
643 			continue;
644 		}
645 
646 		/* Type 2 map.  Gotta find out the details */
647 		pmap_id = (struct regid *)&pmap->data[4];
648 		bzero(&regid_id[0], UDF_REGID_ID_SIZE);
649 		bcopy(&pmap_id->id[0], &regid_id[0], UDF_REGID_ID_SIZE);
650 
651 		if (bcmp(&regid_id[0], "*UDF Sparable Partition",
652 		    UDF_REGID_ID_SIZE)) {
653 			kprintf("Unsupported partition map: %s\n", &regid_id[0]);
654 			return(1);
655 		}
656 
657 		pms = &pmap->pms;
658 		udfmp->s_table = kmalloc(pms->st_size, M_UDFMOUNT,
659 					M_WAITOK | M_ZERO);
660 
661 		/* Calculate the number of sectors per packet. */
662 		/* XXX Logical or physical? */
663 		udfmp->p_sectors = pms->packet_len / udfmp->bsize;
664 
665 		/*
666 		 * XXX If reading the first Sparing Table fails, should look
667 		 * for another table.
668 		 */
669 		if ((error = udf_readlblks(udfmp, pms->st_loc[0], pms->st_size,
670 		    &bp)) != 0) {
671 			if (bp)
672 				brelse(bp);
673 			kprintf("Failed to read Sparing Table at sector %d\n",
674 			    pms->st_loc[0]);
675 			return(error);
676 		}
677 		bcopy(bp->b_data, udfmp->s_table, pms->st_size);
678 		brelse(bp);
679 
680 		if (udf_checktag(&udfmp->s_table->tag, 0)) {
681 			kprintf("Invalid sparing table found\n");
682 			return(EINVAL);
683 		}
684 
685 		/* See how many valid entries there are here.  The list is
686 		 * supposed to be sorted. 0xfffffff0 and higher are not valid
687 		 */
688 		for (i = 0; i < udfmp->s_table->rt_l; i++) {
689 			udfmp->s_table_entries = i;
690 			if (udfmp->s_table->entries[i].org >= 0xfffffff0)
691 				break;
692 		}
693 	}
694 
695 	return(0);
696 }
697