xref: /openbmc/linux/fs/udf/super.c (revision f7777dcc)
1 /*
2  * super.c
3  *
4  * PURPOSE
5  *  Super block routines for the OSTA-UDF(tm) filesystem.
6  *
7  * DESCRIPTION
8  *  OSTA-UDF(tm) = Optical Storage Technology Association
9  *  Universal Disk Format.
10  *
11  *  This code is based on version 2.00 of the UDF specification,
12  *  and revision 3 of the ECMA 167 standard [equivalent to ISO 13346].
13  *    http://www.osta.org/
14  *    http://www.ecma.ch/
15  *    http://www.iso.org/
16  *
17  * COPYRIGHT
18  *  This file is distributed under the terms of the GNU General Public
19  *  License (GPL). Copies of the GPL can be obtained from:
20  *    ftp://prep.ai.mit.edu/pub/gnu/GPL
21  *  Each contributing author retains all rights to their own work.
22  *
23  *  (C) 1998 Dave Boynton
24  *  (C) 1998-2004 Ben Fennema
25  *  (C) 2000 Stelias Computing Inc
26  *
27  * HISTORY
28  *
29  *  09/24/98 dgb  changed to allow compiling outside of kernel, and
30  *                added some debugging.
31  *  10/01/98 dgb  updated to allow (some) possibility of compiling w/2.0.34
32  *  10/16/98      attempting some multi-session support
33  *  10/17/98      added freespace count for "df"
34  *  11/11/98 gr   added novrs option
35  *  11/26/98 dgb  added fileset,anchor mount options
36  *  12/06/98 blf  really hosed things royally. vat/sparing support. sequenced
37  *                vol descs. rewrote option handling based on isofs
38  *  12/20/98      find the free space bitmap (if it exists)
39  */
40 
41 #include "udfdecl.h"
42 
43 #include <linux/blkdev.h>
44 #include <linux/slab.h>
45 #include <linux/kernel.h>
46 #include <linux/module.h>
47 #include <linux/parser.h>
48 #include <linux/stat.h>
49 #include <linux/cdrom.h>
50 #include <linux/nls.h>
51 #include <linux/buffer_head.h>
52 #include <linux/vfs.h>
53 #include <linux/vmalloc.h>
54 #include <linux/errno.h>
55 #include <linux/mount.h>
56 #include <linux/seq_file.h>
57 #include <linux/bitmap.h>
58 #include <linux/crc-itu-t.h>
59 #include <linux/log2.h>
60 #include <asm/byteorder.h>
61 
62 #include "udf_sb.h"
63 #include "udf_i.h"
64 
65 #include <linux/init.h>
66 #include <asm/uaccess.h>
67 
68 #define VDS_POS_PRIMARY_VOL_DESC	0
69 #define VDS_POS_UNALLOC_SPACE_DESC	1
70 #define VDS_POS_LOGICAL_VOL_DESC	2
71 #define VDS_POS_PARTITION_DESC		3
72 #define VDS_POS_IMP_USE_VOL_DESC	4
73 #define VDS_POS_VOL_DESC_PTR		5
74 #define VDS_POS_TERMINATING_DESC	6
75 #define VDS_POS_LENGTH			7
76 
77 #define UDF_DEFAULT_BLOCKSIZE 2048
78 
79 enum { UDF_MAX_LINKS = 0xffff };
80 
81 /* These are the "meat" - everything else is stuffing */
82 static int udf_fill_super(struct super_block *, void *, int);
83 static void udf_put_super(struct super_block *);
84 static int udf_sync_fs(struct super_block *, int);
85 static int udf_remount_fs(struct super_block *, int *, char *);
86 static void udf_load_logicalvolint(struct super_block *, struct kernel_extent_ad);
87 static int udf_find_fileset(struct super_block *, struct kernel_lb_addr *,
88 			    struct kernel_lb_addr *);
89 static void udf_load_fileset(struct super_block *, struct buffer_head *,
90 			     struct kernel_lb_addr *);
91 static void udf_open_lvid(struct super_block *);
92 static void udf_close_lvid(struct super_block *);
93 static unsigned int udf_count_free(struct super_block *);
94 static int udf_statfs(struct dentry *, struct kstatfs *);
95 static int udf_show_options(struct seq_file *, struct dentry *);
96 
97 struct logicalVolIntegrityDescImpUse *udf_sb_lvidiu(struct super_block *sb)
98 {
99 	struct logicalVolIntegrityDesc *lvid;
100 	unsigned int partnum;
101 	unsigned int offset;
102 
103 	if (!UDF_SB(sb)->s_lvid_bh)
104 		return NULL;
105 	lvid = (struct logicalVolIntegrityDesc *)UDF_SB(sb)->s_lvid_bh->b_data;
106 	partnum = le32_to_cpu(lvid->numOfPartitions);
107 	if ((sb->s_blocksize - sizeof(struct logicalVolIntegrityDescImpUse) -
108 	     offsetof(struct logicalVolIntegrityDesc, impUse)) /
109 	     (2 * sizeof(uint32_t)) < partnum) {
110 		udf_err(sb, "Logical volume integrity descriptor corrupted "
111 			"(numOfPartitions = %u)!\n", partnum);
112 		return NULL;
113 	}
114 	/* The offset is to skip freeSpaceTable and sizeTable arrays */
115 	offset = partnum * 2 * sizeof(uint32_t);
116 	return (struct logicalVolIntegrityDescImpUse *)&(lvid->impUse[offset]);
117 }
118 
119 /* UDF filesystem type */
120 static struct dentry *udf_mount(struct file_system_type *fs_type,
121 		      int flags, const char *dev_name, void *data)
122 {
123 	return mount_bdev(fs_type, flags, dev_name, data, udf_fill_super);
124 }
125 
126 static struct file_system_type udf_fstype = {
127 	.owner		= THIS_MODULE,
128 	.name		= "udf",
129 	.mount		= udf_mount,
130 	.kill_sb	= kill_block_super,
131 	.fs_flags	= FS_REQUIRES_DEV,
132 };
133 MODULE_ALIAS_FS("udf");
134 
135 static struct kmem_cache *udf_inode_cachep;
136 
137 static struct inode *udf_alloc_inode(struct super_block *sb)
138 {
139 	struct udf_inode_info *ei;
140 	ei = kmem_cache_alloc(udf_inode_cachep, GFP_KERNEL);
141 	if (!ei)
142 		return NULL;
143 
144 	ei->i_unique = 0;
145 	ei->i_lenExtents = 0;
146 	ei->i_next_alloc_block = 0;
147 	ei->i_next_alloc_goal = 0;
148 	ei->i_strat4096 = 0;
149 	init_rwsem(&ei->i_data_sem);
150 	ei->cached_extent.lstart = -1;
151 	spin_lock_init(&ei->i_extent_cache_lock);
152 
153 	return &ei->vfs_inode;
154 }
155 
156 static void udf_i_callback(struct rcu_head *head)
157 {
158 	struct inode *inode = container_of(head, struct inode, i_rcu);
159 	kmem_cache_free(udf_inode_cachep, UDF_I(inode));
160 }
161 
162 static void udf_destroy_inode(struct inode *inode)
163 {
164 	call_rcu(&inode->i_rcu, udf_i_callback);
165 }
166 
167 static void init_once(void *foo)
168 {
169 	struct udf_inode_info *ei = (struct udf_inode_info *)foo;
170 
171 	ei->i_ext.i_data = NULL;
172 	inode_init_once(&ei->vfs_inode);
173 }
174 
175 static int init_inodecache(void)
176 {
177 	udf_inode_cachep = kmem_cache_create("udf_inode_cache",
178 					     sizeof(struct udf_inode_info),
179 					     0, (SLAB_RECLAIM_ACCOUNT |
180 						 SLAB_MEM_SPREAD),
181 					     init_once);
182 	if (!udf_inode_cachep)
183 		return -ENOMEM;
184 	return 0;
185 }
186 
187 static void destroy_inodecache(void)
188 {
189 	/*
190 	 * Make sure all delayed rcu free inodes are flushed before we
191 	 * destroy cache.
192 	 */
193 	rcu_barrier();
194 	kmem_cache_destroy(udf_inode_cachep);
195 }
196 
197 /* Superblock operations */
198 static const struct super_operations udf_sb_ops = {
199 	.alloc_inode	= udf_alloc_inode,
200 	.destroy_inode	= udf_destroy_inode,
201 	.write_inode	= udf_write_inode,
202 	.evict_inode	= udf_evict_inode,
203 	.put_super	= udf_put_super,
204 	.sync_fs	= udf_sync_fs,
205 	.statfs		= udf_statfs,
206 	.remount_fs	= udf_remount_fs,
207 	.show_options	= udf_show_options,
208 };
209 
210 struct udf_options {
211 	unsigned char novrs;
212 	unsigned int blocksize;
213 	unsigned int session;
214 	unsigned int lastblock;
215 	unsigned int anchor;
216 	unsigned int volume;
217 	unsigned short partition;
218 	unsigned int fileset;
219 	unsigned int rootdir;
220 	unsigned int flags;
221 	umode_t umask;
222 	kgid_t gid;
223 	kuid_t uid;
224 	umode_t fmode;
225 	umode_t dmode;
226 	struct nls_table *nls_map;
227 };
228 
229 static int __init init_udf_fs(void)
230 {
231 	int err;
232 
233 	err = init_inodecache();
234 	if (err)
235 		goto out1;
236 	err = register_filesystem(&udf_fstype);
237 	if (err)
238 		goto out;
239 
240 	return 0;
241 
242 out:
243 	destroy_inodecache();
244 
245 out1:
246 	return err;
247 }
248 
249 static void __exit exit_udf_fs(void)
250 {
251 	unregister_filesystem(&udf_fstype);
252 	destroy_inodecache();
253 }
254 
255 module_init(init_udf_fs)
256 module_exit(exit_udf_fs)
257 
258 static int udf_sb_alloc_partition_maps(struct super_block *sb, u32 count)
259 {
260 	struct udf_sb_info *sbi = UDF_SB(sb);
261 
262 	sbi->s_partmaps = kcalloc(count, sizeof(struct udf_part_map),
263 				  GFP_KERNEL);
264 	if (!sbi->s_partmaps) {
265 		udf_err(sb, "Unable to allocate space for %d partition maps\n",
266 			count);
267 		sbi->s_partitions = 0;
268 		return -ENOMEM;
269 	}
270 
271 	sbi->s_partitions = count;
272 	return 0;
273 }
274 
275 static void udf_sb_free_bitmap(struct udf_bitmap *bitmap)
276 {
277 	int i;
278 	int nr_groups = bitmap->s_nr_groups;
279 	int size = sizeof(struct udf_bitmap) + (sizeof(struct buffer_head *) *
280 						nr_groups);
281 
282 	for (i = 0; i < nr_groups; i++)
283 		if (bitmap->s_block_bitmap[i])
284 			brelse(bitmap->s_block_bitmap[i]);
285 
286 	if (size <= PAGE_SIZE)
287 		kfree(bitmap);
288 	else
289 		vfree(bitmap);
290 }
291 
292 static void udf_free_partition(struct udf_part_map *map)
293 {
294 	int i;
295 	struct udf_meta_data *mdata;
296 
297 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
298 		iput(map->s_uspace.s_table);
299 	if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE)
300 		iput(map->s_fspace.s_table);
301 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
302 		udf_sb_free_bitmap(map->s_uspace.s_bitmap);
303 	if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP)
304 		udf_sb_free_bitmap(map->s_fspace.s_bitmap);
305 	if (map->s_partition_type == UDF_SPARABLE_MAP15)
306 		for (i = 0; i < 4; i++)
307 			brelse(map->s_type_specific.s_sparing.s_spar_map[i]);
308 	else if (map->s_partition_type == UDF_METADATA_MAP25) {
309 		mdata = &map->s_type_specific.s_metadata;
310 		iput(mdata->s_metadata_fe);
311 		mdata->s_metadata_fe = NULL;
312 
313 		iput(mdata->s_mirror_fe);
314 		mdata->s_mirror_fe = NULL;
315 
316 		iput(mdata->s_bitmap_fe);
317 		mdata->s_bitmap_fe = NULL;
318 	}
319 }
320 
321 static void udf_sb_free_partitions(struct super_block *sb)
322 {
323 	struct udf_sb_info *sbi = UDF_SB(sb);
324 	int i;
325 	if (sbi->s_partmaps == NULL)
326 		return;
327 	for (i = 0; i < sbi->s_partitions; i++)
328 		udf_free_partition(&sbi->s_partmaps[i]);
329 	kfree(sbi->s_partmaps);
330 	sbi->s_partmaps = NULL;
331 }
332 
333 static int udf_show_options(struct seq_file *seq, struct dentry *root)
334 {
335 	struct super_block *sb = root->d_sb;
336 	struct udf_sb_info *sbi = UDF_SB(sb);
337 
338 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT))
339 		seq_puts(seq, ",nostrict");
340 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_BLOCKSIZE_SET))
341 		seq_printf(seq, ",bs=%lu", sb->s_blocksize);
342 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
343 		seq_puts(seq, ",unhide");
344 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
345 		seq_puts(seq, ",undelete");
346 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_USE_AD_IN_ICB))
347 		seq_puts(seq, ",noadinicb");
348 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_USE_SHORT_AD))
349 		seq_puts(seq, ",shortad");
350 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_FORGET))
351 		seq_puts(seq, ",uid=forget");
352 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_IGNORE))
353 		seq_puts(seq, ",uid=ignore");
354 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_FORGET))
355 		seq_puts(seq, ",gid=forget");
356 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_IGNORE))
357 		seq_puts(seq, ",gid=ignore");
358 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET))
359 		seq_printf(seq, ",uid=%u", from_kuid(&init_user_ns, sbi->s_uid));
360 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET))
361 		seq_printf(seq, ",gid=%u", from_kgid(&init_user_ns, sbi->s_gid));
362 	if (sbi->s_umask != 0)
363 		seq_printf(seq, ",umask=%ho", sbi->s_umask);
364 	if (sbi->s_fmode != UDF_INVALID_MODE)
365 		seq_printf(seq, ",mode=%ho", sbi->s_fmode);
366 	if (sbi->s_dmode != UDF_INVALID_MODE)
367 		seq_printf(seq, ",dmode=%ho", sbi->s_dmode);
368 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_SESSION_SET))
369 		seq_printf(seq, ",session=%u", sbi->s_session);
370 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_LASTBLOCK_SET))
371 		seq_printf(seq, ",lastblock=%u", sbi->s_last_block);
372 	if (sbi->s_anchor != 0)
373 		seq_printf(seq, ",anchor=%u", sbi->s_anchor);
374 	/*
375 	 * volume, partition, fileset and rootdir seem to be ignored
376 	 * currently
377 	 */
378 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8))
379 		seq_puts(seq, ",utf8");
380 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP) && sbi->s_nls_map)
381 		seq_printf(seq, ",iocharset=%s", sbi->s_nls_map->charset);
382 
383 	return 0;
384 }
385 
386 /*
387  * udf_parse_options
388  *
389  * PURPOSE
390  *	Parse mount options.
391  *
392  * DESCRIPTION
393  *	The following mount options are supported:
394  *
395  *	gid=		Set the default group.
396  *	umask=		Set the default umask.
397  *	mode=		Set the default file permissions.
398  *	dmode=		Set the default directory permissions.
399  *	uid=		Set the default user.
400  *	bs=		Set the block size.
401  *	unhide		Show otherwise hidden files.
402  *	undelete	Show deleted files in lists.
403  *	adinicb		Embed data in the inode (default)
404  *	noadinicb	Don't embed data in the inode
405  *	shortad		Use short ad's
406  *	longad		Use long ad's (default)
407  *	nostrict	Unset strict conformance
408  *	iocharset=	Set the NLS character set
409  *
410  *	The remaining are for debugging and disaster recovery:
411  *
412  *	novrs		Skip volume sequence recognition
413  *
414  *	The following expect a offset from 0.
415  *
416  *	session=	Set the CDROM session (default= last session)
417  *	anchor=		Override standard anchor location. (default= 256)
418  *	volume=		Override the VolumeDesc location. (unused)
419  *	partition=	Override the PartitionDesc location. (unused)
420  *	lastblock=	Set the last block of the filesystem/
421  *
422  *	The following expect a offset from the partition root.
423  *
424  *	fileset=	Override the fileset block location. (unused)
425  *	rootdir=	Override the root directory location. (unused)
426  *		WARNING: overriding the rootdir to a non-directory may
427  *		yield highly unpredictable results.
428  *
429  * PRE-CONDITIONS
430  *	options		Pointer to mount options string.
431  *	uopts		Pointer to mount options variable.
432  *
433  * POST-CONDITIONS
434  *	<return>	1	Mount options parsed okay.
435  *	<return>	0	Error parsing mount options.
436  *
437  * HISTORY
438  *	July 1, 1997 - Andrew E. Mileski
439  *	Written, tested, and released.
440  */
441 
442 enum {
443 	Opt_novrs, Opt_nostrict, Opt_bs, Opt_unhide, Opt_undelete,
444 	Opt_noadinicb, Opt_adinicb, Opt_shortad, Opt_longad,
445 	Opt_gid, Opt_uid, Opt_umask, Opt_session, Opt_lastblock,
446 	Opt_anchor, Opt_volume, Opt_partition, Opt_fileset,
447 	Opt_rootdir, Opt_utf8, Opt_iocharset,
448 	Opt_err, Opt_uforget, Opt_uignore, Opt_gforget, Opt_gignore,
449 	Opt_fmode, Opt_dmode
450 };
451 
452 static const match_table_t tokens = {
453 	{Opt_novrs,	"novrs"},
454 	{Opt_nostrict,	"nostrict"},
455 	{Opt_bs,	"bs=%u"},
456 	{Opt_unhide,	"unhide"},
457 	{Opt_undelete,	"undelete"},
458 	{Opt_noadinicb,	"noadinicb"},
459 	{Opt_adinicb,	"adinicb"},
460 	{Opt_shortad,	"shortad"},
461 	{Opt_longad,	"longad"},
462 	{Opt_uforget,	"uid=forget"},
463 	{Opt_uignore,	"uid=ignore"},
464 	{Opt_gforget,	"gid=forget"},
465 	{Opt_gignore,	"gid=ignore"},
466 	{Opt_gid,	"gid=%u"},
467 	{Opt_uid,	"uid=%u"},
468 	{Opt_umask,	"umask=%o"},
469 	{Opt_session,	"session=%u"},
470 	{Opt_lastblock,	"lastblock=%u"},
471 	{Opt_anchor,	"anchor=%u"},
472 	{Opt_volume,	"volume=%u"},
473 	{Opt_partition,	"partition=%u"},
474 	{Opt_fileset,	"fileset=%u"},
475 	{Opt_rootdir,	"rootdir=%u"},
476 	{Opt_utf8,	"utf8"},
477 	{Opt_iocharset,	"iocharset=%s"},
478 	{Opt_fmode,     "mode=%o"},
479 	{Opt_dmode,     "dmode=%o"},
480 	{Opt_err,	NULL}
481 };
482 
483 static int udf_parse_options(char *options, struct udf_options *uopt,
484 			     bool remount)
485 {
486 	char *p;
487 	int option;
488 
489 	uopt->novrs = 0;
490 	uopt->partition = 0xFFFF;
491 	uopt->session = 0xFFFFFFFF;
492 	uopt->lastblock = 0;
493 	uopt->anchor = 0;
494 	uopt->volume = 0xFFFFFFFF;
495 	uopt->rootdir = 0xFFFFFFFF;
496 	uopt->fileset = 0xFFFFFFFF;
497 	uopt->nls_map = NULL;
498 
499 	if (!options)
500 		return 1;
501 
502 	while ((p = strsep(&options, ",")) != NULL) {
503 		substring_t args[MAX_OPT_ARGS];
504 		int token;
505 		if (!*p)
506 			continue;
507 
508 		token = match_token(p, tokens, args);
509 		switch (token) {
510 		case Opt_novrs:
511 			uopt->novrs = 1;
512 			break;
513 		case Opt_bs:
514 			if (match_int(&args[0], &option))
515 				return 0;
516 			uopt->blocksize = option;
517 			uopt->flags |= (1 << UDF_FLAG_BLOCKSIZE_SET);
518 			break;
519 		case Opt_unhide:
520 			uopt->flags |= (1 << UDF_FLAG_UNHIDE);
521 			break;
522 		case Opt_undelete:
523 			uopt->flags |= (1 << UDF_FLAG_UNDELETE);
524 			break;
525 		case Opt_noadinicb:
526 			uopt->flags &= ~(1 << UDF_FLAG_USE_AD_IN_ICB);
527 			break;
528 		case Opt_adinicb:
529 			uopt->flags |= (1 << UDF_FLAG_USE_AD_IN_ICB);
530 			break;
531 		case Opt_shortad:
532 			uopt->flags |= (1 << UDF_FLAG_USE_SHORT_AD);
533 			break;
534 		case Opt_longad:
535 			uopt->flags &= ~(1 << UDF_FLAG_USE_SHORT_AD);
536 			break;
537 		case Opt_gid:
538 			if (match_int(args, &option))
539 				return 0;
540 			uopt->gid = make_kgid(current_user_ns(), option);
541 			if (!gid_valid(uopt->gid))
542 				return 0;
543 			uopt->flags |= (1 << UDF_FLAG_GID_SET);
544 			break;
545 		case Opt_uid:
546 			if (match_int(args, &option))
547 				return 0;
548 			uopt->uid = make_kuid(current_user_ns(), option);
549 			if (!uid_valid(uopt->uid))
550 				return 0;
551 			uopt->flags |= (1 << UDF_FLAG_UID_SET);
552 			break;
553 		case Opt_umask:
554 			if (match_octal(args, &option))
555 				return 0;
556 			uopt->umask = option;
557 			break;
558 		case Opt_nostrict:
559 			uopt->flags &= ~(1 << UDF_FLAG_STRICT);
560 			break;
561 		case Opt_session:
562 			if (match_int(args, &option))
563 				return 0;
564 			uopt->session = option;
565 			if (!remount)
566 				uopt->flags |= (1 << UDF_FLAG_SESSION_SET);
567 			break;
568 		case Opt_lastblock:
569 			if (match_int(args, &option))
570 				return 0;
571 			uopt->lastblock = option;
572 			if (!remount)
573 				uopt->flags |= (1 << UDF_FLAG_LASTBLOCK_SET);
574 			break;
575 		case Opt_anchor:
576 			if (match_int(args, &option))
577 				return 0;
578 			uopt->anchor = option;
579 			break;
580 		case Opt_volume:
581 			if (match_int(args, &option))
582 				return 0;
583 			uopt->volume = option;
584 			break;
585 		case Opt_partition:
586 			if (match_int(args, &option))
587 				return 0;
588 			uopt->partition = option;
589 			break;
590 		case Opt_fileset:
591 			if (match_int(args, &option))
592 				return 0;
593 			uopt->fileset = option;
594 			break;
595 		case Opt_rootdir:
596 			if (match_int(args, &option))
597 				return 0;
598 			uopt->rootdir = option;
599 			break;
600 		case Opt_utf8:
601 			uopt->flags |= (1 << UDF_FLAG_UTF8);
602 			break;
603 #ifdef CONFIG_UDF_NLS
604 		case Opt_iocharset:
605 			uopt->nls_map = load_nls(args[0].from);
606 			uopt->flags |= (1 << UDF_FLAG_NLS_MAP);
607 			break;
608 #endif
609 		case Opt_uignore:
610 			uopt->flags |= (1 << UDF_FLAG_UID_IGNORE);
611 			break;
612 		case Opt_uforget:
613 			uopt->flags |= (1 << UDF_FLAG_UID_FORGET);
614 			break;
615 		case Opt_gignore:
616 			uopt->flags |= (1 << UDF_FLAG_GID_IGNORE);
617 			break;
618 		case Opt_gforget:
619 			uopt->flags |= (1 << UDF_FLAG_GID_FORGET);
620 			break;
621 		case Opt_fmode:
622 			if (match_octal(args, &option))
623 				return 0;
624 			uopt->fmode = option & 0777;
625 			break;
626 		case Opt_dmode:
627 			if (match_octal(args, &option))
628 				return 0;
629 			uopt->dmode = option & 0777;
630 			break;
631 		default:
632 			pr_err("bad mount option \"%s\" or missing value\n", p);
633 			return 0;
634 		}
635 	}
636 	return 1;
637 }
638 
639 static int udf_remount_fs(struct super_block *sb, int *flags, char *options)
640 {
641 	struct udf_options uopt;
642 	struct udf_sb_info *sbi = UDF_SB(sb);
643 	int error = 0;
644 	struct logicalVolIntegrityDescImpUse *lvidiu = udf_sb_lvidiu(sb);
645 
646 	if (lvidiu) {
647 		int write_rev = le16_to_cpu(lvidiu->minUDFWriteRev);
648 		if (write_rev > UDF_MAX_WRITE_VERSION && !(*flags & MS_RDONLY))
649 			return -EACCES;
650 	}
651 
652 	uopt.flags = sbi->s_flags;
653 	uopt.uid   = sbi->s_uid;
654 	uopt.gid   = sbi->s_gid;
655 	uopt.umask = sbi->s_umask;
656 	uopt.fmode = sbi->s_fmode;
657 	uopt.dmode = sbi->s_dmode;
658 
659 	if (!udf_parse_options(options, &uopt, true))
660 		return -EINVAL;
661 
662 	write_lock(&sbi->s_cred_lock);
663 	sbi->s_flags = uopt.flags;
664 	sbi->s_uid   = uopt.uid;
665 	sbi->s_gid   = uopt.gid;
666 	sbi->s_umask = uopt.umask;
667 	sbi->s_fmode = uopt.fmode;
668 	sbi->s_dmode = uopt.dmode;
669 	write_unlock(&sbi->s_cred_lock);
670 
671 	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
672 		goto out_unlock;
673 
674 	if (*flags & MS_RDONLY)
675 		udf_close_lvid(sb);
676 	else
677 		udf_open_lvid(sb);
678 
679 out_unlock:
680 	return error;
681 }
682 
683 /* Check Volume Structure Descriptors (ECMA 167 2/9.1) */
684 /* We also check any "CD-ROM Volume Descriptor Set" (ECMA 167 2/8.3.1) */
685 static loff_t udf_check_vsd(struct super_block *sb)
686 {
687 	struct volStructDesc *vsd = NULL;
688 	loff_t sector = 32768;
689 	int sectorsize;
690 	struct buffer_head *bh = NULL;
691 	int nsr02 = 0;
692 	int nsr03 = 0;
693 	struct udf_sb_info *sbi;
694 
695 	sbi = UDF_SB(sb);
696 	if (sb->s_blocksize < sizeof(struct volStructDesc))
697 		sectorsize = sizeof(struct volStructDesc);
698 	else
699 		sectorsize = sb->s_blocksize;
700 
701 	sector += (sbi->s_session << sb->s_blocksize_bits);
702 
703 	udf_debug("Starting at sector %u (%ld byte sectors)\n",
704 		  (unsigned int)(sector >> sb->s_blocksize_bits),
705 		  sb->s_blocksize);
706 	/* Process the sequence (if applicable) */
707 	for (; !nsr02 && !nsr03; sector += sectorsize) {
708 		/* Read a block */
709 		bh = udf_tread(sb, sector >> sb->s_blocksize_bits);
710 		if (!bh)
711 			break;
712 
713 		/* Look for ISO  descriptors */
714 		vsd = (struct volStructDesc *)(bh->b_data +
715 					      (sector & (sb->s_blocksize - 1)));
716 
717 		if (vsd->stdIdent[0] == 0) {
718 			brelse(bh);
719 			break;
720 		} else if (!strncmp(vsd->stdIdent, VSD_STD_ID_CD001,
721 				    VSD_STD_ID_LEN)) {
722 			switch (vsd->structType) {
723 			case 0:
724 				udf_debug("ISO9660 Boot Record found\n");
725 				break;
726 			case 1:
727 				udf_debug("ISO9660 Primary Volume Descriptor found\n");
728 				break;
729 			case 2:
730 				udf_debug("ISO9660 Supplementary Volume Descriptor found\n");
731 				break;
732 			case 3:
733 				udf_debug("ISO9660 Volume Partition Descriptor found\n");
734 				break;
735 			case 255:
736 				udf_debug("ISO9660 Volume Descriptor Set Terminator found\n");
737 				break;
738 			default:
739 				udf_debug("ISO9660 VRS (%u) found\n",
740 					  vsd->structType);
741 				break;
742 			}
743 		} else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BEA01,
744 				    VSD_STD_ID_LEN))
745 			; /* nothing */
746 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_TEA01,
747 				    VSD_STD_ID_LEN)) {
748 			brelse(bh);
749 			break;
750 		} else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR02,
751 				    VSD_STD_ID_LEN))
752 			nsr02 = sector;
753 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR03,
754 				    VSD_STD_ID_LEN))
755 			nsr03 = sector;
756 		brelse(bh);
757 	}
758 
759 	if (nsr03)
760 		return nsr03;
761 	else if (nsr02)
762 		return nsr02;
763 	else if (sector - (sbi->s_session << sb->s_blocksize_bits) == 32768)
764 		return -1;
765 	else
766 		return 0;
767 }
768 
769 static int udf_find_fileset(struct super_block *sb,
770 			    struct kernel_lb_addr *fileset,
771 			    struct kernel_lb_addr *root)
772 {
773 	struct buffer_head *bh = NULL;
774 	long lastblock;
775 	uint16_t ident;
776 	struct udf_sb_info *sbi;
777 
778 	if (fileset->logicalBlockNum != 0xFFFFFFFF ||
779 	    fileset->partitionReferenceNum != 0xFFFF) {
780 		bh = udf_read_ptagged(sb, fileset, 0, &ident);
781 
782 		if (!bh) {
783 			return 1;
784 		} else if (ident != TAG_IDENT_FSD) {
785 			brelse(bh);
786 			return 1;
787 		}
788 
789 	}
790 
791 	sbi = UDF_SB(sb);
792 	if (!bh) {
793 		/* Search backwards through the partitions */
794 		struct kernel_lb_addr newfileset;
795 
796 /* --> cvg: FIXME - is it reasonable? */
797 		return 1;
798 
799 		for (newfileset.partitionReferenceNum = sbi->s_partitions - 1;
800 		     (newfileset.partitionReferenceNum != 0xFFFF &&
801 		      fileset->logicalBlockNum == 0xFFFFFFFF &&
802 		      fileset->partitionReferenceNum == 0xFFFF);
803 		     newfileset.partitionReferenceNum--) {
804 			lastblock = sbi->s_partmaps
805 					[newfileset.partitionReferenceNum]
806 						.s_partition_len;
807 			newfileset.logicalBlockNum = 0;
808 
809 			do {
810 				bh = udf_read_ptagged(sb, &newfileset, 0,
811 						      &ident);
812 				if (!bh) {
813 					newfileset.logicalBlockNum++;
814 					continue;
815 				}
816 
817 				switch (ident) {
818 				case TAG_IDENT_SBD:
819 				{
820 					struct spaceBitmapDesc *sp;
821 					sp = (struct spaceBitmapDesc *)
822 								bh->b_data;
823 					newfileset.logicalBlockNum += 1 +
824 						((le32_to_cpu(sp->numOfBytes) +
825 						  sizeof(struct spaceBitmapDesc)
826 						  - 1) >> sb->s_blocksize_bits);
827 					brelse(bh);
828 					break;
829 				}
830 				case TAG_IDENT_FSD:
831 					*fileset = newfileset;
832 					break;
833 				default:
834 					newfileset.logicalBlockNum++;
835 					brelse(bh);
836 					bh = NULL;
837 					break;
838 				}
839 			} while (newfileset.logicalBlockNum < lastblock &&
840 				 fileset->logicalBlockNum == 0xFFFFFFFF &&
841 				 fileset->partitionReferenceNum == 0xFFFF);
842 		}
843 	}
844 
845 	if ((fileset->logicalBlockNum != 0xFFFFFFFF ||
846 	     fileset->partitionReferenceNum != 0xFFFF) && bh) {
847 		udf_debug("Fileset at block=%d, partition=%d\n",
848 			  fileset->logicalBlockNum,
849 			  fileset->partitionReferenceNum);
850 
851 		sbi->s_partition = fileset->partitionReferenceNum;
852 		udf_load_fileset(sb, bh, root);
853 		brelse(bh);
854 		return 0;
855 	}
856 	return 1;
857 }
858 
859 /*
860  * Load primary Volume Descriptor Sequence
861  *
862  * Return <0 on error, 0 on success. -EAGAIN is special meaning next sequence
863  * should be tried.
864  */
865 static int udf_load_pvoldesc(struct super_block *sb, sector_t block)
866 {
867 	struct primaryVolDesc *pvoldesc;
868 	struct ustr *instr, *outstr;
869 	struct buffer_head *bh;
870 	uint16_t ident;
871 	int ret = -ENOMEM;
872 
873 	instr = kmalloc(sizeof(struct ustr), GFP_NOFS);
874 	if (!instr)
875 		return -ENOMEM;
876 
877 	outstr = kmalloc(sizeof(struct ustr), GFP_NOFS);
878 	if (!outstr)
879 		goto out1;
880 
881 	bh = udf_read_tagged(sb, block, block, &ident);
882 	if (!bh) {
883 		ret = -EAGAIN;
884 		goto out2;
885 	}
886 
887 	if (ident != TAG_IDENT_PVD) {
888 		ret = -EIO;
889 		goto out_bh;
890 	}
891 
892 	pvoldesc = (struct primaryVolDesc *)bh->b_data;
893 
894 	if (udf_disk_stamp_to_time(&UDF_SB(sb)->s_record_time,
895 			      pvoldesc->recordingDateAndTime)) {
896 #ifdef UDFFS_DEBUG
897 		struct timestamp *ts = &pvoldesc->recordingDateAndTime;
898 		udf_debug("recording time %04u/%02u/%02u %02u:%02u (%x)\n",
899 			  le16_to_cpu(ts->year), ts->month, ts->day, ts->hour,
900 			  ts->minute, le16_to_cpu(ts->typeAndTimezone));
901 #endif
902 	}
903 
904 	if (!udf_build_ustr(instr, pvoldesc->volIdent, 32))
905 		if (udf_CS0toUTF8(outstr, instr)) {
906 			strncpy(UDF_SB(sb)->s_volume_ident, outstr->u_name,
907 				outstr->u_len > 31 ? 31 : outstr->u_len);
908 			udf_debug("volIdent[] = '%s'\n",
909 				  UDF_SB(sb)->s_volume_ident);
910 		}
911 
912 	if (!udf_build_ustr(instr, pvoldesc->volSetIdent, 128))
913 		if (udf_CS0toUTF8(outstr, instr))
914 			udf_debug("volSetIdent[] = '%s'\n", outstr->u_name);
915 
916 	ret = 0;
917 out_bh:
918 	brelse(bh);
919 out2:
920 	kfree(outstr);
921 out1:
922 	kfree(instr);
923 	return ret;
924 }
925 
926 struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
927 					u32 meta_file_loc, u32 partition_num)
928 {
929 	struct kernel_lb_addr addr;
930 	struct inode *metadata_fe;
931 
932 	addr.logicalBlockNum = meta_file_loc;
933 	addr.partitionReferenceNum = partition_num;
934 
935 	metadata_fe = udf_iget(sb, &addr);
936 
937 	if (metadata_fe == NULL)
938 		udf_warn(sb, "metadata inode efe not found\n");
939 	else if (UDF_I(metadata_fe)->i_alloc_type != ICBTAG_FLAG_AD_SHORT) {
940 		udf_warn(sb, "metadata inode efe does not have short allocation descriptors!\n");
941 		iput(metadata_fe);
942 		metadata_fe = NULL;
943 	}
944 
945 	return metadata_fe;
946 }
947 
948 static int udf_load_metadata_files(struct super_block *sb, int partition)
949 {
950 	struct udf_sb_info *sbi = UDF_SB(sb);
951 	struct udf_part_map *map;
952 	struct udf_meta_data *mdata;
953 	struct kernel_lb_addr addr;
954 
955 	map = &sbi->s_partmaps[partition];
956 	mdata = &map->s_type_specific.s_metadata;
957 
958 	/* metadata address */
959 	udf_debug("Metadata file location: block = %d part = %d\n",
960 		  mdata->s_meta_file_loc, map->s_partition_num);
961 
962 	mdata->s_metadata_fe = udf_find_metadata_inode_efe(sb,
963 		mdata->s_meta_file_loc, map->s_partition_num);
964 
965 	if (mdata->s_metadata_fe == NULL) {
966 		/* mirror file entry */
967 		udf_debug("Mirror metadata file location: block = %d part = %d\n",
968 			  mdata->s_mirror_file_loc, map->s_partition_num);
969 
970 		mdata->s_mirror_fe = udf_find_metadata_inode_efe(sb,
971 			mdata->s_mirror_file_loc, map->s_partition_num);
972 
973 		if (mdata->s_mirror_fe == NULL) {
974 			udf_err(sb, "Both metadata and mirror metadata inode efe can not found\n");
975 			return -EIO;
976 		}
977 	}
978 
979 	/*
980 	 * bitmap file entry
981 	 * Note:
982 	 * Load only if bitmap file location differs from 0xFFFFFFFF (DCN-5102)
983 	*/
984 	if (mdata->s_bitmap_file_loc != 0xFFFFFFFF) {
985 		addr.logicalBlockNum = mdata->s_bitmap_file_loc;
986 		addr.partitionReferenceNum = map->s_partition_num;
987 
988 		udf_debug("Bitmap file location: block = %d part = %d\n",
989 			  addr.logicalBlockNum, addr.partitionReferenceNum);
990 
991 		mdata->s_bitmap_fe = udf_iget(sb, &addr);
992 		if (mdata->s_bitmap_fe == NULL) {
993 			if (sb->s_flags & MS_RDONLY)
994 				udf_warn(sb, "bitmap inode efe not found but it's ok since the disc is mounted read-only\n");
995 			else {
996 				udf_err(sb, "bitmap inode efe not found and attempted read-write mount\n");
997 				return -EIO;
998 			}
999 		}
1000 	}
1001 
1002 	udf_debug("udf_load_metadata_files Ok\n");
1003 	return 0;
1004 }
1005 
1006 static void udf_load_fileset(struct super_block *sb, struct buffer_head *bh,
1007 			     struct kernel_lb_addr *root)
1008 {
1009 	struct fileSetDesc *fset;
1010 
1011 	fset = (struct fileSetDesc *)bh->b_data;
1012 
1013 	*root = lelb_to_cpu(fset->rootDirectoryICB.extLocation);
1014 
1015 	UDF_SB(sb)->s_serial_number = le16_to_cpu(fset->descTag.tagSerialNum);
1016 
1017 	udf_debug("Rootdir at block=%d, partition=%d\n",
1018 		  root->logicalBlockNum, root->partitionReferenceNum);
1019 }
1020 
1021 int udf_compute_nr_groups(struct super_block *sb, u32 partition)
1022 {
1023 	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
1024 	return DIV_ROUND_UP(map->s_partition_len +
1025 			    (sizeof(struct spaceBitmapDesc) << 3),
1026 			    sb->s_blocksize * 8);
1027 }
1028 
1029 static struct udf_bitmap *udf_sb_alloc_bitmap(struct super_block *sb, u32 index)
1030 {
1031 	struct udf_bitmap *bitmap;
1032 	int nr_groups;
1033 	int size;
1034 
1035 	nr_groups = udf_compute_nr_groups(sb, index);
1036 	size = sizeof(struct udf_bitmap) +
1037 		(sizeof(struct buffer_head *) * nr_groups);
1038 
1039 	if (size <= PAGE_SIZE)
1040 		bitmap = kzalloc(size, GFP_KERNEL);
1041 	else
1042 		bitmap = vzalloc(size); /* TODO: get rid of vzalloc */
1043 
1044 	if (bitmap == NULL)
1045 		return NULL;
1046 
1047 	bitmap->s_nr_groups = nr_groups;
1048 	return bitmap;
1049 }
1050 
1051 static int udf_fill_partdesc_info(struct super_block *sb,
1052 		struct partitionDesc *p, int p_index)
1053 {
1054 	struct udf_part_map *map;
1055 	struct udf_sb_info *sbi = UDF_SB(sb);
1056 	struct partitionHeaderDesc *phd;
1057 
1058 	map = &sbi->s_partmaps[p_index];
1059 
1060 	map->s_partition_len = le32_to_cpu(p->partitionLength); /* blocks */
1061 	map->s_partition_root = le32_to_cpu(p->partitionStartingLocation);
1062 
1063 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_READ_ONLY))
1064 		map->s_partition_flags |= UDF_PART_FLAG_READ_ONLY;
1065 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_WRITE_ONCE))
1066 		map->s_partition_flags |= UDF_PART_FLAG_WRITE_ONCE;
1067 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_REWRITABLE))
1068 		map->s_partition_flags |= UDF_PART_FLAG_REWRITABLE;
1069 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_OVERWRITABLE))
1070 		map->s_partition_flags |= UDF_PART_FLAG_OVERWRITABLE;
1071 
1072 	udf_debug("Partition (%d type %x) starts at physical %d, block length %d\n",
1073 		  p_index, map->s_partition_type,
1074 		  map->s_partition_root, map->s_partition_len);
1075 
1076 	if (strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR02) &&
1077 	    strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR03))
1078 		return 0;
1079 
1080 	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1081 	if (phd->unallocSpaceTable.extLength) {
1082 		struct kernel_lb_addr loc = {
1083 			.logicalBlockNum = le32_to_cpu(
1084 				phd->unallocSpaceTable.extPosition),
1085 			.partitionReferenceNum = p_index,
1086 		};
1087 
1088 		map->s_uspace.s_table = udf_iget(sb, &loc);
1089 		if (!map->s_uspace.s_table) {
1090 			udf_debug("cannot load unallocSpaceTable (part %d)\n",
1091 				  p_index);
1092 			return -EIO;
1093 		}
1094 		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_TABLE;
1095 		udf_debug("unallocSpaceTable (part %d) @ %ld\n",
1096 			  p_index, map->s_uspace.s_table->i_ino);
1097 	}
1098 
1099 	if (phd->unallocSpaceBitmap.extLength) {
1100 		struct udf_bitmap *bitmap = udf_sb_alloc_bitmap(sb, p_index);
1101 		if (!bitmap)
1102 			return -ENOMEM;
1103 		map->s_uspace.s_bitmap = bitmap;
1104 		bitmap->s_extPosition = le32_to_cpu(
1105 				phd->unallocSpaceBitmap.extPosition);
1106 		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_BITMAP;
1107 		udf_debug("unallocSpaceBitmap (part %d) @ %d\n",
1108 			  p_index, bitmap->s_extPosition);
1109 	}
1110 
1111 	if (phd->partitionIntegrityTable.extLength)
1112 		udf_debug("partitionIntegrityTable (part %d)\n", p_index);
1113 
1114 	if (phd->freedSpaceTable.extLength) {
1115 		struct kernel_lb_addr loc = {
1116 			.logicalBlockNum = le32_to_cpu(
1117 				phd->freedSpaceTable.extPosition),
1118 			.partitionReferenceNum = p_index,
1119 		};
1120 
1121 		map->s_fspace.s_table = udf_iget(sb, &loc);
1122 		if (!map->s_fspace.s_table) {
1123 			udf_debug("cannot load freedSpaceTable (part %d)\n",
1124 				  p_index);
1125 			return -EIO;
1126 		}
1127 
1128 		map->s_partition_flags |= UDF_PART_FLAG_FREED_TABLE;
1129 		udf_debug("freedSpaceTable (part %d) @ %ld\n",
1130 			  p_index, map->s_fspace.s_table->i_ino);
1131 	}
1132 
1133 	if (phd->freedSpaceBitmap.extLength) {
1134 		struct udf_bitmap *bitmap = udf_sb_alloc_bitmap(sb, p_index);
1135 		if (!bitmap)
1136 			return -ENOMEM;
1137 		map->s_fspace.s_bitmap = bitmap;
1138 		bitmap->s_extPosition = le32_to_cpu(
1139 				phd->freedSpaceBitmap.extPosition);
1140 		map->s_partition_flags |= UDF_PART_FLAG_FREED_BITMAP;
1141 		udf_debug("freedSpaceBitmap (part %d) @ %d\n",
1142 			  p_index, bitmap->s_extPosition);
1143 	}
1144 	return 0;
1145 }
1146 
1147 static void udf_find_vat_block(struct super_block *sb, int p_index,
1148 			       int type1_index, sector_t start_block)
1149 {
1150 	struct udf_sb_info *sbi = UDF_SB(sb);
1151 	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1152 	sector_t vat_block;
1153 	struct kernel_lb_addr ino;
1154 
1155 	/*
1156 	 * VAT file entry is in the last recorded block. Some broken disks have
1157 	 * it a few blocks before so try a bit harder...
1158 	 */
1159 	ino.partitionReferenceNum = type1_index;
1160 	for (vat_block = start_block;
1161 	     vat_block >= map->s_partition_root &&
1162 	     vat_block >= start_block - 3 &&
1163 	     !sbi->s_vat_inode; vat_block--) {
1164 		ino.logicalBlockNum = vat_block - map->s_partition_root;
1165 		sbi->s_vat_inode = udf_iget(sb, &ino);
1166 	}
1167 }
1168 
1169 static int udf_load_vat(struct super_block *sb, int p_index, int type1_index)
1170 {
1171 	struct udf_sb_info *sbi = UDF_SB(sb);
1172 	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1173 	struct buffer_head *bh = NULL;
1174 	struct udf_inode_info *vati;
1175 	uint32_t pos;
1176 	struct virtualAllocationTable20 *vat20;
1177 	sector_t blocks = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
1178 
1179 	udf_find_vat_block(sb, p_index, type1_index, sbi->s_last_block);
1180 	if (!sbi->s_vat_inode &&
1181 	    sbi->s_last_block != blocks - 1) {
1182 		pr_notice("Failed to read VAT inode from the last recorded block (%lu), retrying with the last block of the device (%lu).\n",
1183 			  (unsigned long)sbi->s_last_block,
1184 			  (unsigned long)blocks - 1);
1185 		udf_find_vat_block(sb, p_index, type1_index, blocks - 1);
1186 	}
1187 	if (!sbi->s_vat_inode)
1188 		return -EIO;
1189 
1190 	if (map->s_partition_type == UDF_VIRTUAL_MAP15) {
1191 		map->s_type_specific.s_virtual.s_start_offset = 0;
1192 		map->s_type_specific.s_virtual.s_num_entries =
1193 			(sbi->s_vat_inode->i_size - 36) >> 2;
1194 	} else if (map->s_partition_type == UDF_VIRTUAL_MAP20) {
1195 		vati = UDF_I(sbi->s_vat_inode);
1196 		if (vati->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1197 			pos = udf_block_map(sbi->s_vat_inode, 0);
1198 			bh = sb_bread(sb, pos);
1199 			if (!bh)
1200 				return -EIO;
1201 			vat20 = (struct virtualAllocationTable20 *)bh->b_data;
1202 		} else {
1203 			vat20 = (struct virtualAllocationTable20 *)
1204 							vati->i_ext.i_data;
1205 		}
1206 
1207 		map->s_type_specific.s_virtual.s_start_offset =
1208 			le16_to_cpu(vat20->lengthHeader);
1209 		map->s_type_specific.s_virtual.s_num_entries =
1210 			(sbi->s_vat_inode->i_size -
1211 				map->s_type_specific.s_virtual.
1212 					s_start_offset) >> 2;
1213 		brelse(bh);
1214 	}
1215 	return 0;
1216 }
1217 
1218 /*
1219  * Load partition descriptor block
1220  *
1221  * Returns <0 on error, 0 on success, -EAGAIN is special - try next descriptor
1222  * sequence.
1223  */
1224 static int udf_load_partdesc(struct super_block *sb, sector_t block)
1225 {
1226 	struct buffer_head *bh;
1227 	struct partitionDesc *p;
1228 	struct udf_part_map *map;
1229 	struct udf_sb_info *sbi = UDF_SB(sb);
1230 	int i, type1_idx;
1231 	uint16_t partitionNumber;
1232 	uint16_t ident;
1233 	int ret;
1234 
1235 	bh = udf_read_tagged(sb, block, block, &ident);
1236 	if (!bh)
1237 		return -EAGAIN;
1238 	if (ident != TAG_IDENT_PD) {
1239 		ret = 0;
1240 		goto out_bh;
1241 	}
1242 
1243 	p = (struct partitionDesc *)bh->b_data;
1244 	partitionNumber = le16_to_cpu(p->partitionNumber);
1245 
1246 	/* First scan for TYPE1, SPARABLE and METADATA partitions */
1247 	for (i = 0; i < sbi->s_partitions; i++) {
1248 		map = &sbi->s_partmaps[i];
1249 		udf_debug("Searching map: (%d == %d)\n",
1250 			  map->s_partition_num, partitionNumber);
1251 		if (map->s_partition_num == partitionNumber &&
1252 		    (map->s_partition_type == UDF_TYPE1_MAP15 ||
1253 		     map->s_partition_type == UDF_SPARABLE_MAP15))
1254 			break;
1255 	}
1256 
1257 	if (i >= sbi->s_partitions) {
1258 		udf_debug("Partition (%d) not found in partition map\n",
1259 			  partitionNumber);
1260 		ret = 0;
1261 		goto out_bh;
1262 	}
1263 
1264 	ret = udf_fill_partdesc_info(sb, p, i);
1265 	if (ret < 0)
1266 		goto out_bh;
1267 
1268 	/*
1269 	 * Now rescan for VIRTUAL or METADATA partitions when SPARABLE and
1270 	 * PHYSICAL partitions are already set up
1271 	 */
1272 	type1_idx = i;
1273 	for (i = 0; i < sbi->s_partitions; i++) {
1274 		map = &sbi->s_partmaps[i];
1275 
1276 		if (map->s_partition_num == partitionNumber &&
1277 		    (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1278 		     map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1279 		     map->s_partition_type == UDF_METADATA_MAP25))
1280 			break;
1281 	}
1282 
1283 	if (i >= sbi->s_partitions) {
1284 		ret = 0;
1285 		goto out_bh;
1286 	}
1287 
1288 	ret = udf_fill_partdesc_info(sb, p, i);
1289 	if (ret < 0)
1290 		goto out_bh;
1291 
1292 	if (map->s_partition_type == UDF_METADATA_MAP25) {
1293 		ret = udf_load_metadata_files(sb, i);
1294 		if (ret < 0) {
1295 			udf_err(sb, "error loading MetaData partition map %d\n",
1296 				i);
1297 			goto out_bh;
1298 		}
1299 	} else {
1300 		/*
1301 		 * If we have a partition with virtual map, we don't handle
1302 		 * writing to it (we overwrite blocks instead of relocating
1303 		 * them).
1304 		 */
1305 		if (!(sb->s_flags & MS_RDONLY)) {
1306 			ret = -EACCES;
1307 			goto out_bh;
1308 		}
1309 		ret = udf_load_vat(sb, i, type1_idx);
1310 		if (ret < 0)
1311 			goto out_bh;
1312 	}
1313 	ret = 0;
1314 out_bh:
1315 	/* In case loading failed, we handle cleanup in udf_fill_super */
1316 	brelse(bh);
1317 	return ret;
1318 }
1319 
1320 static int udf_load_sparable_map(struct super_block *sb,
1321 				 struct udf_part_map *map,
1322 				 struct sparablePartitionMap *spm)
1323 {
1324 	uint32_t loc;
1325 	uint16_t ident;
1326 	struct sparingTable *st;
1327 	struct udf_sparing_data *sdata = &map->s_type_specific.s_sparing;
1328 	int i;
1329 	struct buffer_head *bh;
1330 
1331 	map->s_partition_type = UDF_SPARABLE_MAP15;
1332 	sdata->s_packet_len = le16_to_cpu(spm->packetLength);
1333 	if (!is_power_of_2(sdata->s_packet_len)) {
1334 		udf_err(sb, "error loading logical volume descriptor: "
1335 			"Invalid packet length %u\n",
1336 			(unsigned)sdata->s_packet_len);
1337 		return -EIO;
1338 	}
1339 	if (spm->numSparingTables > 4) {
1340 		udf_err(sb, "error loading logical volume descriptor: "
1341 			"Too many sparing tables (%d)\n",
1342 			(int)spm->numSparingTables);
1343 		return -EIO;
1344 	}
1345 
1346 	for (i = 0; i < spm->numSparingTables; i++) {
1347 		loc = le32_to_cpu(spm->locSparingTable[i]);
1348 		bh = udf_read_tagged(sb, loc, loc, &ident);
1349 		if (!bh)
1350 			continue;
1351 
1352 		st = (struct sparingTable *)bh->b_data;
1353 		if (ident != 0 ||
1354 		    strncmp(st->sparingIdent.ident, UDF_ID_SPARING,
1355 			    strlen(UDF_ID_SPARING)) ||
1356 		    sizeof(*st) + le16_to_cpu(st->reallocationTableLen) >
1357 							sb->s_blocksize) {
1358 			brelse(bh);
1359 			continue;
1360 		}
1361 
1362 		sdata->s_spar_map[i] = bh;
1363 	}
1364 	map->s_partition_func = udf_get_pblock_spar15;
1365 	return 0;
1366 }
1367 
1368 static int udf_load_logicalvol(struct super_block *sb, sector_t block,
1369 			       struct kernel_lb_addr *fileset)
1370 {
1371 	struct logicalVolDesc *lvd;
1372 	int i, offset;
1373 	uint8_t type;
1374 	struct udf_sb_info *sbi = UDF_SB(sb);
1375 	struct genericPartitionMap *gpm;
1376 	uint16_t ident;
1377 	struct buffer_head *bh;
1378 	unsigned int table_len;
1379 	int ret;
1380 
1381 	bh = udf_read_tagged(sb, block, block, &ident);
1382 	if (!bh)
1383 		return -EAGAIN;
1384 	BUG_ON(ident != TAG_IDENT_LVD);
1385 	lvd = (struct logicalVolDesc *)bh->b_data;
1386 	table_len = le32_to_cpu(lvd->mapTableLength);
1387 	if (table_len > sb->s_blocksize - sizeof(*lvd)) {
1388 		udf_err(sb, "error loading logical volume descriptor: "
1389 			"Partition table too long (%u > %lu)\n", table_len,
1390 			sb->s_blocksize - sizeof(*lvd));
1391 		ret = -EIO;
1392 		goto out_bh;
1393 	}
1394 
1395 	ret = udf_sb_alloc_partition_maps(sb, le32_to_cpu(lvd->numPartitionMaps));
1396 	if (ret)
1397 		goto out_bh;
1398 
1399 	for (i = 0, offset = 0;
1400 	     i < sbi->s_partitions && offset < table_len;
1401 	     i++, offset += gpm->partitionMapLength) {
1402 		struct udf_part_map *map = &sbi->s_partmaps[i];
1403 		gpm = (struct genericPartitionMap *)
1404 				&(lvd->partitionMaps[offset]);
1405 		type = gpm->partitionMapType;
1406 		if (type == 1) {
1407 			struct genericPartitionMap1 *gpm1 =
1408 				(struct genericPartitionMap1 *)gpm;
1409 			map->s_partition_type = UDF_TYPE1_MAP15;
1410 			map->s_volumeseqnum = le16_to_cpu(gpm1->volSeqNum);
1411 			map->s_partition_num = le16_to_cpu(gpm1->partitionNum);
1412 			map->s_partition_func = NULL;
1413 		} else if (type == 2) {
1414 			struct udfPartitionMap2 *upm2 =
1415 						(struct udfPartitionMap2 *)gpm;
1416 			if (!strncmp(upm2->partIdent.ident, UDF_ID_VIRTUAL,
1417 						strlen(UDF_ID_VIRTUAL))) {
1418 				u16 suf =
1419 					le16_to_cpu(((__le16 *)upm2->partIdent.
1420 							identSuffix)[0]);
1421 				if (suf < 0x0200) {
1422 					map->s_partition_type =
1423 							UDF_VIRTUAL_MAP15;
1424 					map->s_partition_func =
1425 							udf_get_pblock_virt15;
1426 				} else {
1427 					map->s_partition_type =
1428 							UDF_VIRTUAL_MAP20;
1429 					map->s_partition_func =
1430 							udf_get_pblock_virt20;
1431 				}
1432 			} else if (!strncmp(upm2->partIdent.ident,
1433 						UDF_ID_SPARABLE,
1434 						strlen(UDF_ID_SPARABLE))) {
1435 				ret = udf_load_sparable_map(sb, map,
1436 					(struct sparablePartitionMap *)gpm);
1437 				if (ret < 0)
1438 					goto out_bh;
1439 			} else if (!strncmp(upm2->partIdent.ident,
1440 						UDF_ID_METADATA,
1441 						strlen(UDF_ID_METADATA))) {
1442 				struct udf_meta_data *mdata =
1443 					&map->s_type_specific.s_metadata;
1444 				struct metadataPartitionMap *mdm =
1445 						(struct metadataPartitionMap *)
1446 						&(lvd->partitionMaps[offset]);
1447 				udf_debug("Parsing Logical vol part %d type %d  id=%s\n",
1448 					  i, type, UDF_ID_METADATA);
1449 
1450 				map->s_partition_type = UDF_METADATA_MAP25;
1451 				map->s_partition_func = udf_get_pblock_meta25;
1452 
1453 				mdata->s_meta_file_loc   =
1454 					le32_to_cpu(mdm->metadataFileLoc);
1455 				mdata->s_mirror_file_loc =
1456 					le32_to_cpu(mdm->metadataMirrorFileLoc);
1457 				mdata->s_bitmap_file_loc =
1458 					le32_to_cpu(mdm->metadataBitmapFileLoc);
1459 				mdata->s_alloc_unit_size =
1460 					le32_to_cpu(mdm->allocUnitSize);
1461 				mdata->s_align_unit_size =
1462 					le16_to_cpu(mdm->alignUnitSize);
1463 				if (mdm->flags & 0x01)
1464 					mdata->s_flags |= MF_DUPLICATE_MD;
1465 
1466 				udf_debug("Metadata Ident suffix=0x%x\n",
1467 					  le16_to_cpu(*(__le16 *)
1468 						      mdm->partIdent.identSuffix));
1469 				udf_debug("Metadata part num=%d\n",
1470 					  le16_to_cpu(mdm->partitionNum));
1471 				udf_debug("Metadata part alloc unit size=%d\n",
1472 					  le32_to_cpu(mdm->allocUnitSize));
1473 				udf_debug("Metadata file loc=%d\n",
1474 					  le32_to_cpu(mdm->metadataFileLoc));
1475 				udf_debug("Mirror file loc=%d\n",
1476 					  le32_to_cpu(mdm->metadataMirrorFileLoc));
1477 				udf_debug("Bitmap file loc=%d\n",
1478 					  le32_to_cpu(mdm->metadataBitmapFileLoc));
1479 				udf_debug("Flags: %d %d\n",
1480 					  mdata->s_flags, mdm->flags);
1481 			} else {
1482 				udf_debug("Unknown ident: %s\n",
1483 					  upm2->partIdent.ident);
1484 				continue;
1485 			}
1486 			map->s_volumeseqnum = le16_to_cpu(upm2->volSeqNum);
1487 			map->s_partition_num = le16_to_cpu(upm2->partitionNum);
1488 		}
1489 		udf_debug("Partition (%d:%d) type %d on volume %d\n",
1490 			  i, map->s_partition_num, type, map->s_volumeseqnum);
1491 	}
1492 
1493 	if (fileset) {
1494 		struct long_ad *la = (struct long_ad *)&(lvd->logicalVolContentsUse[0]);
1495 
1496 		*fileset = lelb_to_cpu(la->extLocation);
1497 		udf_debug("FileSet found in LogicalVolDesc at block=%d, partition=%d\n",
1498 			  fileset->logicalBlockNum,
1499 			  fileset->partitionReferenceNum);
1500 	}
1501 	if (lvd->integritySeqExt.extLength)
1502 		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
1503 	ret = 0;
1504 out_bh:
1505 	brelse(bh);
1506 	return ret;
1507 }
1508 
1509 /*
1510  * udf_load_logicalvolint
1511  *
1512  */
1513 static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_ad loc)
1514 {
1515 	struct buffer_head *bh = NULL;
1516 	uint16_t ident;
1517 	struct udf_sb_info *sbi = UDF_SB(sb);
1518 	struct logicalVolIntegrityDesc *lvid;
1519 
1520 	while (loc.extLength > 0 &&
1521 	       (bh = udf_read_tagged(sb, loc.extLocation,
1522 				     loc.extLocation, &ident)) &&
1523 	       ident == TAG_IDENT_LVID) {
1524 		sbi->s_lvid_bh = bh;
1525 		lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
1526 
1527 		if (lvid->nextIntegrityExt.extLength)
1528 			udf_load_logicalvolint(sb,
1529 				leea_to_cpu(lvid->nextIntegrityExt));
1530 
1531 		if (sbi->s_lvid_bh != bh)
1532 			brelse(bh);
1533 		loc.extLength -= sb->s_blocksize;
1534 		loc.extLocation++;
1535 	}
1536 	if (sbi->s_lvid_bh != bh)
1537 		brelse(bh);
1538 }
1539 
1540 /*
1541  * Process a main/reserve volume descriptor sequence.
1542  *   @block		First block of first extent of the sequence.
1543  *   @lastblock		Lastblock of first extent of the sequence.
1544  *   @fileset		There we store extent containing root fileset
1545  *
1546  * Returns <0 on error, 0 on success. -EAGAIN is special - try next descriptor
1547  * sequence
1548  */
1549 static noinline int udf_process_sequence(
1550 		struct super_block *sb,
1551 		sector_t block, sector_t lastblock,
1552 		struct kernel_lb_addr *fileset)
1553 {
1554 	struct buffer_head *bh = NULL;
1555 	struct udf_vds_record vds[VDS_POS_LENGTH];
1556 	struct udf_vds_record *curr;
1557 	struct generic_desc *gd;
1558 	struct volDescPtr *vdp;
1559 	int done = 0;
1560 	uint32_t vdsn;
1561 	uint16_t ident;
1562 	long next_s = 0, next_e = 0;
1563 	int ret;
1564 
1565 	memset(vds, 0, sizeof(struct udf_vds_record) * VDS_POS_LENGTH);
1566 
1567 	/*
1568 	 * Read the main descriptor sequence and find which descriptors
1569 	 * are in it.
1570 	 */
1571 	for (; (!done && block <= lastblock); block++) {
1572 
1573 		bh = udf_read_tagged(sb, block, block, &ident);
1574 		if (!bh) {
1575 			udf_err(sb,
1576 				"Block %llu of volume descriptor sequence is corrupted or we could not read it\n",
1577 				(unsigned long long)block);
1578 			return -EAGAIN;
1579 		}
1580 
1581 		/* Process each descriptor (ISO 13346 3/8.3-8.4) */
1582 		gd = (struct generic_desc *)bh->b_data;
1583 		vdsn = le32_to_cpu(gd->volDescSeqNum);
1584 		switch (ident) {
1585 		case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1586 			curr = &vds[VDS_POS_PRIMARY_VOL_DESC];
1587 			if (vdsn >= curr->volDescSeqNum) {
1588 				curr->volDescSeqNum = vdsn;
1589 				curr->block = block;
1590 			}
1591 			break;
1592 		case TAG_IDENT_VDP: /* ISO 13346 3/10.3 */
1593 			curr = &vds[VDS_POS_VOL_DESC_PTR];
1594 			if (vdsn >= curr->volDescSeqNum) {
1595 				curr->volDescSeqNum = vdsn;
1596 				curr->block = block;
1597 
1598 				vdp = (struct volDescPtr *)bh->b_data;
1599 				next_s = le32_to_cpu(
1600 					vdp->nextVolDescSeqExt.extLocation);
1601 				next_e = le32_to_cpu(
1602 					vdp->nextVolDescSeqExt.extLength);
1603 				next_e = next_e >> sb->s_blocksize_bits;
1604 				next_e += next_s;
1605 			}
1606 			break;
1607 		case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1608 			curr = &vds[VDS_POS_IMP_USE_VOL_DESC];
1609 			if (vdsn >= curr->volDescSeqNum) {
1610 				curr->volDescSeqNum = vdsn;
1611 				curr->block = block;
1612 			}
1613 			break;
1614 		case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1615 			curr = &vds[VDS_POS_PARTITION_DESC];
1616 			if (!curr->block)
1617 				curr->block = block;
1618 			break;
1619 		case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1620 			curr = &vds[VDS_POS_LOGICAL_VOL_DESC];
1621 			if (vdsn >= curr->volDescSeqNum) {
1622 				curr->volDescSeqNum = vdsn;
1623 				curr->block = block;
1624 			}
1625 			break;
1626 		case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1627 			curr = &vds[VDS_POS_UNALLOC_SPACE_DESC];
1628 			if (vdsn >= curr->volDescSeqNum) {
1629 				curr->volDescSeqNum = vdsn;
1630 				curr->block = block;
1631 			}
1632 			break;
1633 		case TAG_IDENT_TD: /* ISO 13346 3/10.9 */
1634 			vds[VDS_POS_TERMINATING_DESC].block = block;
1635 			if (next_e) {
1636 				block = next_s;
1637 				lastblock = next_e;
1638 				next_s = next_e = 0;
1639 			} else
1640 				done = 1;
1641 			break;
1642 		}
1643 		brelse(bh);
1644 	}
1645 	/*
1646 	 * Now read interesting descriptors again and process them
1647 	 * in a suitable order
1648 	 */
1649 	if (!vds[VDS_POS_PRIMARY_VOL_DESC].block) {
1650 		udf_err(sb, "Primary Volume Descriptor not found!\n");
1651 		return -EAGAIN;
1652 	}
1653 	ret = udf_load_pvoldesc(sb, vds[VDS_POS_PRIMARY_VOL_DESC].block);
1654 	if (ret < 0)
1655 		return ret;
1656 
1657 	if (vds[VDS_POS_LOGICAL_VOL_DESC].block) {
1658 		ret = udf_load_logicalvol(sb,
1659 					  vds[VDS_POS_LOGICAL_VOL_DESC].block,
1660 					  fileset);
1661 		if (ret < 0)
1662 			return ret;
1663 	}
1664 
1665 	if (vds[VDS_POS_PARTITION_DESC].block) {
1666 		/*
1667 		 * We rescan the whole descriptor sequence to find
1668 		 * partition descriptor blocks and process them.
1669 		 */
1670 		for (block = vds[VDS_POS_PARTITION_DESC].block;
1671 		     block < vds[VDS_POS_TERMINATING_DESC].block;
1672 		     block++) {
1673 			ret = udf_load_partdesc(sb, block);
1674 			if (ret < 0)
1675 				return ret;
1676 		}
1677 	}
1678 
1679 	return 0;
1680 }
1681 
1682 /*
1683  * Load Volume Descriptor Sequence described by anchor in bh
1684  *
1685  * Returns <0 on error, 0 on success
1686  */
1687 static int udf_load_sequence(struct super_block *sb, struct buffer_head *bh,
1688 			     struct kernel_lb_addr *fileset)
1689 {
1690 	struct anchorVolDescPtr *anchor;
1691 	sector_t main_s, main_e, reserve_s, reserve_e;
1692 	int ret;
1693 
1694 	anchor = (struct anchorVolDescPtr *)bh->b_data;
1695 
1696 	/* Locate the main sequence */
1697 	main_s = le32_to_cpu(anchor->mainVolDescSeqExt.extLocation);
1698 	main_e = le32_to_cpu(anchor->mainVolDescSeqExt.extLength);
1699 	main_e = main_e >> sb->s_blocksize_bits;
1700 	main_e += main_s;
1701 
1702 	/* Locate the reserve sequence */
1703 	reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
1704 	reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
1705 	reserve_e = reserve_e >> sb->s_blocksize_bits;
1706 	reserve_e += reserve_s;
1707 
1708 	/* Process the main & reserve sequences */
1709 	/* responsible for finding the PartitionDesc(s) */
1710 	ret = udf_process_sequence(sb, main_s, main_e, fileset);
1711 	if (ret != -EAGAIN)
1712 		return ret;
1713 	udf_sb_free_partitions(sb);
1714 	ret = udf_process_sequence(sb, reserve_s, reserve_e, fileset);
1715 	if (ret < 0) {
1716 		udf_sb_free_partitions(sb);
1717 		/* No sequence was OK, return -EIO */
1718 		if (ret == -EAGAIN)
1719 			ret = -EIO;
1720 	}
1721 	return ret;
1722 }
1723 
1724 /*
1725  * Check whether there is an anchor block in the given block and
1726  * load Volume Descriptor Sequence if so.
1727  *
1728  * Returns <0 on error, 0 on success, -EAGAIN is special - try next anchor
1729  * block
1730  */
1731 static int udf_check_anchor_block(struct super_block *sb, sector_t block,
1732 				  struct kernel_lb_addr *fileset)
1733 {
1734 	struct buffer_head *bh;
1735 	uint16_t ident;
1736 	int ret;
1737 
1738 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV) &&
1739 	    udf_fixed_to_variable(block) >=
1740 	    sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits)
1741 		return -EAGAIN;
1742 
1743 	bh = udf_read_tagged(sb, block, block, &ident);
1744 	if (!bh)
1745 		return -EAGAIN;
1746 	if (ident != TAG_IDENT_AVDP) {
1747 		brelse(bh);
1748 		return -EAGAIN;
1749 	}
1750 	ret = udf_load_sequence(sb, bh, fileset);
1751 	brelse(bh);
1752 	return ret;
1753 }
1754 
1755 /*
1756  * Search for an anchor volume descriptor pointer.
1757  *
1758  * Returns < 0 on error, 0 on success. -EAGAIN is special - try next set
1759  * of anchors.
1760  */
1761 static int udf_scan_anchors(struct super_block *sb, sector_t *lastblock,
1762 			    struct kernel_lb_addr *fileset)
1763 {
1764 	sector_t last[6];
1765 	int i;
1766 	struct udf_sb_info *sbi = UDF_SB(sb);
1767 	int last_count = 0;
1768 	int ret;
1769 
1770 	/* First try user provided anchor */
1771 	if (sbi->s_anchor) {
1772 		ret = udf_check_anchor_block(sb, sbi->s_anchor, fileset);
1773 		if (ret != -EAGAIN)
1774 			return ret;
1775 	}
1776 	/*
1777 	 * according to spec, anchor is in either:
1778 	 *     block 256
1779 	 *     lastblock-256
1780 	 *     lastblock
1781 	 *  however, if the disc isn't closed, it could be 512.
1782 	 */
1783 	ret = udf_check_anchor_block(sb, sbi->s_session + 256, fileset);
1784 	if (ret != -EAGAIN)
1785 		return ret;
1786 	/*
1787 	 * The trouble is which block is the last one. Drives often misreport
1788 	 * this so we try various possibilities.
1789 	 */
1790 	last[last_count++] = *lastblock;
1791 	if (*lastblock >= 1)
1792 		last[last_count++] = *lastblock - 1;
1793 	last[last_count++] = *lastblock + 1;
1794 	if (*lastblock >= 2)
1795 		last[last_count++] = *lastblock - 2;
1796 	if (*lastblock >= 150)
1797 		last[last_count++] = *lastblock - 150;
1798 	if (*lastblock >= 152)
1799 		last[last_count++] = *lastblock - 152;
1800 
1801 	for (i = 0; i < last_count; i++) {
1802 		if (last[i] >= sb->s_bdev->bd_inode->i_size >>
1803 				sb->s_blocksize_bits)
1804 			continue;
1805 		ret = udf_check_anchor_block(sb, last[i], fileset);
1806 		if (ret != -EAGAIN) {
1807 			if (!ret)
1808 				*lastblock = last[i];
1809 			return ret;
1810 		}
1811 		if (last[i] < 256)
1812 			continue;
1813 		ret = udf_check_anchor_block(sb, last[i] - 256, fileset);
1814 		if (ret != -EAGAIN) {
1815 			if (!ret)
1816 				*lastblock = last[i];
1817 			return ret;
1818 		}
1819 	}
1820 
1821 	/* Finally try block 512 in case media is open */
1822 	return udf_check_anchor_block(sb, sbi->s_session + 512, fileset);
1823 }
1824 
1825 /*
1826  * Find an anchor volume descriptor and load Volume Descriptor Sequence from
1827  * area specified by it. The function expects sbi->s_lastblock to be the last
1828  * block on the media.
1829  *
1830  * Return <0 on error, 0 if anchor found. -EAGAIN is special meaning anchor
1831  * was not found.
1832  */
1833 static int udf_find_anchor(struct super_block *sb,
1834 			   struct kernel_lb_addr *fileset)
1835 {
1836 	struct udf_sb_info *sbi = UDF_SB(sb);
1837 	sector_t lastblock = sbi->s_last_block;
1838 	int ret;
1839 
1840 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1841 	if (ret != -EAGAIN)
1842 		goto out;
1843 
1844 	/* No anchor found? Try VARCONV conversion of block numbers */
1845 	UDF_SET_FLAG(sb, UDF_FLAG_VARCONV);
1846 	lastblock = udf_variable_to_fixed(sbi->s_last_block);
1847 	/* Firstly, we try to not convert number of the last block */
1848 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1849 	if (ret != -EAGAIN)
1850 		goto out;
1851 
1852 	lastblock = sbi->s_last_block;
1853 	/* Secondly, we try with converted number of the last block */
1854 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1855 	if (ret < 0) {
1856 		/* VARCONV didn't help. Clear it. */
1857 		UDF_CLEAR_FLAG(sb, UDF_FLAG_VARCONV);
1858 	}
1859 out:
1860 	if (ret == 0)
1861 		sbi->s_last_block = lastblock;
1862 	return ret;
1863 }
1864 
1865 /*
1866  * Check Volume Structure Descriptor, find Anchor block and load Volume
1867  * Descriptor Sequence.
1868  *
1869  * Returns < 0 on error, 0 on success. -EAGAIN is special meaning anchor
1870  * block was not found.
1871  */
1872 static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
1873 			int silent, struct kernel_lb_addr *fileset)
1874 {
1875 	struct udf_sb_info *sbi = UDF_SB(sb);
1876 	loff_t nsr_off;
1877 	int ret;
1878 
1879 	if (!sb_set_blocksize(sb, uopt->blocksize)) {
1880 		if (!silent)
1881 			udf_warn(sb, "Bad block size\n");
1882 		return -EINVAL;
1883 	}
1884 	sbi->s_last_block = uopt->lastblock;
1885 	if (!uopt->novrs) {
1886 		/* Check that it is NSR02 compliant */
1887 		nsr_off = udf_check_vsd(sb);
1888 		if (!nsr_off) {
1889 			if (!silent)
1890 				udf_warn(sb, "No VRS found\n");
1891 			return 0;
1892 		}
1893 		if (nsr_off == -1)
1894 			udf_debug("Failed to read byte 32768. Assuming open disc. Skipping validity check\n");
1895 		if (!sbi->s_last_block)
1896 			sbi->s_last_block = udf_get_last_block(sb);
1897 	} else {
1898 		udf_debug("Validity check skipped because of novrs option\n");
1899 	}
1900 
1901 	/* Look for anchor block and load Volume Descriptor Sequence */
1902 	sbi->s_anchor = uopt->anchor;
1903 	ret = udf_find_anchor(sb, fileset);
1904 	if (ret < 0) {
1905 		if (!silent && ret == -EAGAIN)
1906 			udf_warn(sb, "No anchor found\n");
1907 		return ret;
1908 	}
1909 	return 0;
1910 }
1911 
1912 static void udf_open_lvid(struct super_block *sb)
1913 {
1914 	struct udf_sb_info *sbi = UDF_SB(sb);
1915 	struct buffer_head *bh = sbi->s_lvid_bh;
1916 	struct logicalVolIntegrityDesc *lvid;
1917 	struct logicalVolIntegrityDescImpUse *lvidiu;
1918 
1919 	if (!bh)
1920 		return;
1921 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
1922 	lvidiu = udf_sb_lvidiu(sb);
1923 	if (!lvidiu)
1924 		return;
1925 
1926 	mutex_lock(&sbi->s_alloc_mutex);
1927 	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1928 	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1929 	udf_time_to_disk_stamp(&lvid->recordingDateAndTime,
1930 				CURRENT_TIME);
1931 	lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
1932 
1933 	lvid->descTag.descCRC = cpu_to_le16(
1934 		crc_itu_t(0, (char *)lvid + sizeof(struct tag),
1935 			le16_to_cpu(lvid->descTag.descCRCLength)));
1936 
1937 	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
1938 	mark_buffer_dirty(bh);
1939 	sbi->s_lvid_dirty = 0;
1940 	mutex_unlock(&sbi->s_alloc_mutex);
1941 	/* Make opening of filesystem visible on the media immediately */
1942 	sync_dirty_buffer(bh);
1943 }
1944 
1945 static void udf_close_lvid(struct super_block *sb)
1946 {
1947 	struct udf_sb_info *sbi = UDF_SB(sb);
1948 	struct buffer_head *bh = sbi->s_lvid_bh;
1949 	struct logicalVolIntegrityDesc *lvid;
1950 	struct logicalVolIntegrityDescImpUse *lvidiu;
1951 
1952 	if (!bh)
1953 		return;
1954 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
1955 	lvidiu = udf_sb_lvidiu(sb);
1956 	if (!lvidiu)
1957 		return;
1958 
1959 	mutex_lock(&sbi->s_alloc_mutex);
1960 	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1961 	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1962 	udf_time_to_disk_stamp(&lvid->recordingDateAndTime, CURRENT_TIME);
1963 	if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
1964 		lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
1965 	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
1966 		lvidiu->minUDFReadRev = cpu_to_le16(sbi->s_udfrev);
1967 	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFWriteRev))
1968 		lvidiu->minUDFWriteRev = cpu_to_le16(sbi->s_udfrev);
1969 	lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);
1970 
1971 	lvid->descTag.descCRC = cpu_to_le16(
1972 			crc_itu_t(0, (char *)lvid + sizeof(struct tag),
1973 				le16_to_cpu(lvid->descTag.descCRCLength)));
1974 
1975 	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
1976 	/*
1977 	 * We set buffer uptodate unconditionally here to avoid spurious
1978 	 * warnings from mark_buffer_dirty() when previous EIO has marked
1979 	 * the buffer as !uptodate
1980 	 */
1981 	set_buffer_uptodate(bh);
1982 	mark_buffer_dirty(bh);
1983 	sbi->s_lvid_dirty = 0;
1984 	mutex_unlock(&sbi->s_alloc_mutex);
1985 	/* Make closing of filesystem visible on the media immediately */
1986 	sync_dirty_buffer(bh);
1987 }
1988 
1989 u64 lvid_get_unique_id(struct super_block *sb)
1990 {
1991 	struct buffer_head *bh;
1992 	struct udf_sb_info *sbi = UDF_SB(sb);
1993 	struct logicalVolIntegrityDesc *lvid;
1994 	struct logicalVolHeaderDesc *lvhd;
1995 	u64 uniqueID;
1996 	u64 ret;
1997 
1998 	bh = sbi->s_lvid_bh;
1999 	if (!bh)
2000 		return 0;
2001 
2002 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2003 	lvhd = (struct logicalVolHeaderDesc *)lvid->logicalVolContentsUse;
2004 
2005 	mutex_lock(&sbi->s_alloc_mutex);
2006 	ret = uniqueID = le64_to_cpu(lvhd->uniqueID);
2007 	if (!(++uniqueID & 0xFFFFFFFF))
2008 		uniqueID += 16;
2009 	lvhd->uniqueID = cpu_to_le64(uniqueID);
2010 	mutex_unlock(&sbi->s_alloc_mutex);
2011 	mark_buffer_dirty(bh);
2012 
2013 	return ret;
2014 }
2015 
2016 static int udf_fill_super(struct super_block *sb, void *options, int silent)
2017 {
2018 	int ret = -EINVAL;
2019 	struct inode *inode = NULL;
2020 	struct udf_options uopt;
2021 	struct kernel_lb_addr rootdir, fileset;
2022 	struct udf_sb_info *sbi;
2023 
2024 	uopt.flags = (1 << UDF_FLAG_USE_AD_IN_ICB) | (1 << UDF_FLAG_STRICT);
2025 	uopt.uid = INVALID_UID;
2026 	uopt.gid = INVALID_GID;
2027 	uopt.umask = 0;
2028 	uopt.fmode = UDF_INVALID_MODE;
2029 	uopt.dmode = UDF_INVALID_MODE;
2030 
2031 	sbi = kzalloc(sizeof(struct udf_sb_info), GFP_KERNEL);
2032 	if (!sbi)
2033 		return -ENOMEM;
2034 
2035 	sb->s_fs_info = sbi;
2036 
2037 	mutex_init(&sbi->s_alloc_mutex);
2038 
2039 	if (!udf_parse_options((char *)options, &uopt, false))
2040 		goto error_out;
2041 
2042 	if (uopt.flags & (1 << UDF_FLAG_UTF8) &&
2043 	    uopt.flags & (1 << UDF_FLAG_NLS_MAP)) {
2044 		udf_err(sb, "utf8 cannot be combined with iocharset\n");
2045 		goto error_out;
2046 	}
2047 #ifdef CONFIG_UDF_NLS
2048 	if ((uopt.flags & (1 << UDF_FLAG_NLS_MAP)) && !uopt.nls_map) {
2049 		uopt.nls_map = load_nls_default();
2050 		if (!uopt.nls_map)
2051 			uopt.flags &= ~(1 << UDF_FLAG_NLS_MAP);
2052 		else
2053 			udf_debug("Using default NLS map\n");
2054 	}
2055 #endif
2056 	if (!(uopt.flags & (1 << UDF_FLAG_NLS_MAP)))
2057 		uopt.flags |= (1 << UDF_FLAG_UTF8);
2058 
2059 	fileset.logicalBlockNum = 0xFFFFFFFF;
2060 	fileset.partitionReferenceNum = 0xFFFF;
2061 
2062 	sbi->s_flags = uopt.flags;
2063 	sbi->s_uid = uopt.uid;
2064 	sbi->s_gid = uopt.gid;
2065 	sbi->s_umask = uopt.umask;
2066 	sbi->s_fmode = uopt.fmode;
2067 	sbi->s_dmode = uopt.dmode;
2068 	sbi->s_nls_map = uopt.nls_map;
2069 	rwlock_init(&sbi->s_cred_lock);
2070 
2071 	if (uopt.session == 0xFFFFFFFF)
2072 		sbi->s_session = udf_get_last_session(sb);
2073 	else
2074 		sbi->s_session = uopt.session;
2075 
2076 	udf_debug("Multi-session=%d\n", sbi->s_session);
2077 
2078 	/* Fill in the rest of the superblock */
2079 	sb->s_op = &udf_sb_ops;
2080 	sb->s_export_op = &udf_export_ops;
2081 
2082 	sb->s_magic = UDF_SUPER_MAGIC;
2083 	sb->s_time_gran = 1000;
2084 
2085 	if (uopt.flags & (1 << UDF_FLAG_BLOCKSIZE_SET)) {
2086 		ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2087 	} else {
2088 		uopt.blocksize = bdev_logical_block_size(sb->s_bdev);
2089 		ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2090 		if (ret == -EAGAIN && uopt.blocksize != UDF_DEFAULT_BLOCKSIZE) {
2091 			if (!silent)
2092 				pr_notice("Rescanning with blocksize %d\n",
2093 					  UDF_DEFAULT_BLOCKSIZE);
2094 			brelse(sbi->s_lvid_bh);
2095 			sbi->s_lvid_bh = NULL;
2096 			uopt.blocksize = UDF_DEFAULT_BLOCKSIZE;
2097 			ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2098 		}
2099 	}
2100 	if (ret < 0) {
2101 		if (ret == -EAGAIN) {
2102 			udf_warn(sb, "No partition found (1)\n");
2103 			ret = -EINVAL;
2104 		}
2105 		goto error_out;
2106 	}
2107 
2108 	udf_debug("Lastblock=%d\n", sbi->s_last_block);
2109 
2110 	if (sbi->s_lvid_bh) {
2111 		struct logicalVolIntegrityDescImpUse *lvidiu =
2112 							udf_sb_lvidiu(sb);
2113 		uint16_t minUDFReadRev;
2114 		uint16_t minUDFWriteRev;
2115 
2116 		if (!lvidiu) {
2117 			ret = -EINVAL;
2118 			goto error_out;
2119 		}
2120 		minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev);
2121 		minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev);
2122 		if (minUDFReadRev > UDF_MAX_READ_VERSION) {
2123 			udf_err(sb, "minUDFReadRev=%x (max is %x)\n",
2124 				minUDFReadRev,
2125 				UDF_MAX_READ_VERSION);
2126 			ret = -EINVAL;
2127 			goto error_out;
2128 		} else if (minUDFWriteRev > UDF_MAX_WRITE_VERSION &&
2129 			   !(sb->s_flags & MS_RDONLY)) {
2130 			ret = -EACCES;
2131 			goto error_out;
2132 		}
2133 
2134 		sbi->s_udfrev = minUDFWriteRev;
2135 
2136 		if (minUDFReadRev >= UDF_VERS_USE_EXTENDED_FE)
2137 			UDF_SET_FLAG(sb, UDF_FLAG_USE_EXTENDED_FE);
2138 		if (minUDFReadRev >= UDF_VERS_USE_STREAMS)
2139 			UDF_SET_FLAG(sb, UDF_FLAG_USE_STREAMS);
2140 	}
2141 
2142 	if (!sbi->s_partitions) {
2143 		udf_warn(sb, "No partition found (2)\n");
2144 		ret = -EINVAL;
2145 		goto error_out;
2146 	}
2147 
2148 	if (sbi->s_partmaps[sbi->s_partition].s_partition_flags &
2149 			UDF_PART_FLAG_READ_ONLY &&
2150 	    !(sb->s_flags & MS_RDONLY)) {
2151 		ret = -EACCES;
2152 		goto error_out;
2153 	}
2154 
2155 	if (udf_find_fileset(sb, &fileset, &rootdir)) {
2156 		udf_warn(sb, "No fileset found\n");
2157 		ret = -EINVAL;
2158 		goto error_out;
2159 	}
2160 
2161 	if (!silent) {
2162 		struct timestamp ts;
2163 		udf_time_to_disk_stamp(&ts, sbi->s_record_time);
2164 		udf_info("Mounting volume '%s', timestamp %04u/%02u/%02u %02u:%02u (%x)\n",
2165 			 sbi->s_volume_ident,
2166 			 le16_to_cpu(ts.year), ts.month, ts.day,
2167 			 ts.hour, ts.minute, le16_to_cpu(ts.typeAndTimezone));
2168 	}
2169 	if (!(sb->s_flags & MS_RDONLY))
2170 		udf_open_lvid(sb);
2171 
2172 	/* Assign the root inode */
2173 	/* assign inodes by physical block number */
2174 	/* perhaps it's not extensible enough, but for now ... */
2175 	inode = udf_iget(sb, &rootdir);
2176 	if (!inode) {
2177 		udf_err(sb, "Error in udf_iget, block=%d, partition=%d\n",
2178 		       rootdir.logicalBlockNum, rootdir.partitionReferenceNum);
2179 		ret = -EIO;
2180 		goto error_out;
2181 	}
2182 
2183 	/* Allocate a dentry for the root inode */
2184 	sb->s_root = d_make_root(inode);
2185 	if (!sb->s_root) {
2186 		udf_err(sb, "Couldn't allocate root dentry\n");
2187 		ret = -ENOMEM;
2188 		goto error_out;
2189 	}
2190 	sb->s_maxbytes = MAX_LFS_FILESIZE;
2191 	sb->s_max_links = UDF_MAX_LINKS;
2192 	return 0;
2193 
2194 error_out:
2195 	if (sbi->s_vat_inode)
2196 		iput(sbi->s_vat_inode);
2197 #ifdef CONFIG_UDF_NLS
2198 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
2199 		unload_nls(sbi->s_nls_map);
2200 #endif
2201 	if (!(sb->s_flags & MS_RDONLY))
2202 		udf_close_lvid(sb);
2203 	brelse(sbi->s_lvid_bh);
2204 	udf_sb_free_partitions(sb);
2205 	kfree(sbi);
2206 	sb->s_fs_info = NULL;
2207 
2208 	return ret;
2209 }
2210 
2211 void _udf_err(struct super_block *sb, const char *function,
2212 	      const char *fmt, ...)
2213 {
2214 	struct va_format vaf;
2215 	va_list args;
2216 
2217 	va_start(args, fmt);
2218 
2219 	vaf.fmt = fmt;
2220 	vaf.va = &args;
2221 
2222 	pr_err("error (device %s): %s: %pV", sb->s_id, function, &vaf);
2223 
2224 	va_end(args);
2225 }
2226 
2227 void _udf_warn(struct super_block *sb, const char *function,
2228 	       const char *fmt, ...)
2229 {
2230 	struct va_format vaf;
2231 	va_list args;
2232 
2233 	va_start(args, fmt);
2234 
2235 	vaf.fmt = fmt;
2236 	vaf.va = &args;
2237 
2238 	pr_warn("warning (device %s): %s: %pV", sb->s_id, function, &vaf);
2239 
2240 	va_end(args);
2241 }
2242 
2243 static void udf_put_super(struct super_block *sb)
2244 {
2245 	struct udf_sb_info *sbi;
2246 
2247 	sbi = UDF_SB(sb);
2248 
2249 	if (sbi->s_vat_inode)
2250 		iput(sbi->s_vat_inode);
2251 #ifdef CONFIG_UDF_NLS
2252 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
2253 		unload_nls(sbi->s_nls_map);
2254 #endif
2255 	if (!(sb->s_flags & MS_RDONLY))
2256 		udf_close_lvid(sb);
2257 	brelse(sbi->s_lvid_bh);
2258 	udf_sb_free_partitions(sb);
2259 	kfree(sb->s_fs_info);
2260 	sb->s_fs_info = NULL;
2261 }
2262 
2263 static int udf_sync_fs(struct super_block *sb, int wait)
2264 {
2265 	struct udf_sb_info *sbi = UDF_SB(sb);
2266 
2267 	mutex_lock(&sbi->s_alloc_mutex);
2268 	if (sbi->s_lvid_dirty) {
2269 		/*
2270 		 * Blockdevice will be synced later so we don't have to submit
2271 		 * the buffer for IO
2272 		 */
2273 		mark_buffer_dirty(sbi->s_lvid_bh);
2274 		sbi->s_lvid_dirty = 0;
2275 	}
2276 	mutex_unlock(&sbi->s_alloc_mutex);
2277 
2278 	return 0;
2279 }
2280 
2281 static int udf_statfs(struct dentry *dentry, struct kstatfs *buf)
2282 {
2283 	struct super_block *sb = dentry->d_sb;
2284 	struct udf_sb_info *sbi = UDF_SB(sb);
2285 	struct logicalVolIntegrityDescImpUse *lvidiu;
2286 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
2287 
2288 	lvidiu = udf_sb_lvidiu(sb);
2289 	buf->f_type = UDF_SUPER_MAGIC;
2290 	buf->f_bsize = sb->s_blocksize;
2291 	buf->f_blocks = sbi->s_partmaps[sbi->s_partition].s_partition_len;
2292 	buf->f_bfree = udf_count_free(sb);
2293 	buf->f_bavail = buf->f_bfree;
2294 	buf->f_files = (lvidiu != NULL ? (le32_to_cpu(lvidiu->numFiles) +
2295 					  le32_to_cpu(lvidiu->numDirs)) : 0)
2296 			+ buf->f_bfree;
2297 	buf->f_ffree = buf->f_bfree;
2298 	buf->f_namelen = UDF_NAME_LEN - 2;
2299 	buf->f_fsid.val[0] = (u32)id;
2300 	buf->f_fsid.val[1] = (u32)(id >> 32);
2301 
2302 	return 0;
2303 }
2304 
2305 static unsigned int udf_count_free_bitmap(struct super_block *sb,
2306 					  struct udf_bitmap *bitmap)
2307 {
2308 	struct buffer_head *bh = NULL;
2309 	unsigned int accum = 0;
2310 	int index;
2311 	int block = 0, newblock;
2312 	struct kernel_lb_addr loc;
2313 	uint32_t bytes;
2314 	uint8_t *ptr;
2315 	uint16_t ident;
2316 	struct spaceBitmapDesc *bm;
2317 
2318 	loc.logicalBlockNum = bitmap->s_extPosition;
2319 	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
2320 	bh = udf_read_ptagged(sb, &loc, 0, &ident);
2321 
2322 	if (!bh) {
2323 		udf_err(sb, "udf_count_free failed\n");
2324 		goto out;
2325 	} else if (ident != TAG_IDENT_SBD) {
2326 		brelse(bh);
2327 		udf_err(sb, "udf_count_free failed\n");
2328 		goto out;
2329 	}
2330 
2331 	bm = (struct spaceBitmapDesc *)bh->b_data;
2332 	bytes = le32_to_cpu(bm->numOfBytes);
2333 	index = sizeof(struct spaceBitmapDesc); /* offset in first block only */
2334 	ptr = (uint8_t *)bh->b_data;
2335 
2336 	while (bytes > 0) {
2337 		u32 cur_bytes = min_t(u32, bytes, sb->s_blocksize - index);
2338 		accum += bitmap_weight((const unsigned long *)(ptr + index),
2339 					cur_bytes * 8);
2340 		bytes -= cur_bytes;
2341 		if (bytes) {
2342 			brelse(bh);
2343 			newblock = udf_get_lb_pblock(sb, &loc, ++block);
2344 			bh = udf_tread(sb, newblock);
2345 			if (!bh) {
2346 				udf_debug("read failed\n");
2347 				goto out;
2348 			}
2349 			index = 0;
2350 			ptr = (uint8_t *)bh->b_data;
2351 		}
2352 	}
2353 	brelse(bh);
2354 out:
2355 	return accum;
2356 }
2357 
2358 static unsigned int udf_count_free_table(struct super_block *sb,
2359 					 struct inode *table)
2360 {
2361 	unsigned int accum = 0;
2362 	uint32_t elen;
2363 	struct kernel_lb_addr eloc;
2364 	int8_t etype;
2365 	struct extent_position epos;
2366 
2367 	mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
2368 	epos.block = UDF_I(table)->i_location;
2369 	epos.offset = sizeof(struct unallocSpaceEntry);
2370 	epos.bh = NULL;
2371 
2372 	while ((etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1)
2373 		accum += (elen >> table->i_sb->s_blocksize_bits);
2374 
2375 	brelse(epos.bh);
2376 	mutex_unlock(&UDF_SB(sb)->s_alloc_mutex);
2377 
2378 	return accum;
2379 }
2380 
2381 static unsigned int udf_count_free(struct super_block *sb)
2382 {
2383 	unsigned int accum = 0;
2384 	struct udf_sb_info *sbi;
2385 	struct udf_part_map *map;
2386 
2387 	sbi = UDF_SB(sb);
2388 	if (sbi->s_lvid_bh) {
2389 		struct logicalVolIntegrityDesc *lvid =
2390 			(struct logicalVolIntegrityDesc *)
2391 			sbi->s_lvid_bh->b_data;
2392 		if (le32_to_cpu(lvid->numOfPartitions) > sbi->s_partition) {
2393 			accum = le32_to_cpu(
2394 					lvid->freeSpaceTable[sbi->s_partition]);
2395 			if (accum == 0xFFFFFFFF)
2396 				accum = 0;
2397 		}
2398 	}
2399 
2400 	if (accum)
2401 		return accum;
2402 
2403 	map = &sbi->s_partmaps[sbi->s_partition];
2404 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
2405 		accum += udf_count_free_bitmap(sb,
2406 					       map->s_uspace.s_bitmap);
2407 	}
2408 	if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) {
2409 		accum += udf_count_free_bitmap(sb,
2410 					       map->s_fspace.s_bitmap);
2411 	}
2412 	if (accum)
2413 		return accum;
2414 
2415 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
2416 		accum += udf_count_free_table(sb,
2417 					      map->s_uspace.s_table);
2418 	}
2419 	if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) {
2420 		accum += udf_count_free_table(sb,
2421 					      map->s_fspace.s_table);
2422 	}
2423 
2424 	return accum;
2425 }
2426