xref: /openbmc/linux/fs/udf/super.c (revision eb3fcf00)
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/vfs.h>
52 #include <linux/vmalloc.h>
53 #include <linux/errno.h>
54 #include <linux/mount.h>
55 #include <linux/seq_file.h>
56 #include <linux/bitmap.h>
57 #include <linux/crc-itu-t.h>
58 #include <linux/log2.h>
59 #include <asm/byteorder.h>
60 
61 #include "udf_sb.h"
62 #include "udf_i.h"
63 
64 #include <linux/init.h>
65 #include <linux/uaccess.h>
66 
67 #define VDS_POS_PRIMARY_VOL_DESC	0
68 #define VDS_POS_UNALLOC_SPACE_DESC	1
69 #define VDS_POS_LOGICAL_VOL_DESC	2
70 #define VDS_POS_PARTITION_DESC		3
71 #define VDS_POS_IMP_USE_VOL_DESC	4
72 #define VDS_POS_VOL_DESC_PTR		5
73 #define VDS_POS_TERMINATING_DESC	6
74 #define VDS_POS_LENGTH			7
75 
76 #define UDF_DEFAULT_BLOCKSIZE 2048
77 
78 #define VSD_FIRST_SECTOR_OFFSET		32768
79 #define VSD_MAX_SECTOR_OFFSET		0x800000
80 
81 enum { UDF_MAX_LINKS = 0xffff };
82 
83 /* These are the "meat" - everything else is stuffing */
84 static int udf_fill_super(struct super_block *, void *, int);
85 static void udf_put_super(struct super_block *);
86 static int udf_sync_fs(struct super_block *, int);
87 static int udf_remount_fs(struct super_block *, int *, char *);
88 static void udf_load_logicalvolint(struct super_block *, struct kernel_extent_ad);
89 static int udf_find_fileset(struct super_block *, struct kernel_lb_addr *,
90 			    struct kernel_lb_addr *);
91 static void udf_load_fileset(struct super_block *, struct buffer_head *,
92 			     struct kernel_lb_addr *);
93 static void udf_open_lvid(struct super_block *);
94 static void udf_close_lvid(struct super_block *);
95 static unsigned int udf_count_free(struct super_block *);
96 static int udf_statfs(struct dentry *, struct kstatfs *);
97 static int udf_show_options(struct seq_file *, struct dentry *);
98 
99 struct logicalVolIntegrityDescImpUse *udf_sb_lvidiu(struct super_block *sb)
100 {
101 	struct logicalVolIntegrityDesc *lvid;
102 	unsigned int partnum;
103 	unsigned int offset;
104 
105 	if (!UDF_SB(sb)->s_lvid_bh)
106 		return NULL;
107 	lvid = (struct logicalVolIntegrityDesc *)UDF_SB(sb)->s_lvid_bh->b_data;
108 	partnum = le32_to_cpu(lvid->numOfPartitions);
109 	if ((sb->s_blocksize - sizeof(struct logicalVolIntegrityDescImpUse) -
110 	     offsetof(struct logicalVolIntegrityDesc, impUse)) /
111 	     (2 * sizeof(uint32_t)) < partnum) {
112 		udf_err(sb, "Logical volume integrity descriptor corrupted "
113 			"(numOfPartitions = %u)!\n", partnum);
114 		return NULL;
115 	}
116 	/* The offset is to skip freeSpaceTable and sizeTable arrays */
117 	offset = partnum * 2 * sizeof(uint32_t);
118 	return (struct logicalVolIntegrityDescImpUse *)&(lvid->impUse[offset]);
119 }
120 
121 /* UDF filesystem type */
122 static struct dentry *udf_mount(struct file_system_type *fs_type,
123 		      int flags, const char *dev_name, void *data)
124 {
125 	return mount_bdev(fs_type, flags, dev_name, data, udf_fill_super);
126 }
127 
128 static struct file_system_type udf_fstype = {
129 	.owner		= THIS_MODULE,
130 	.name		= "udf",
131 	.mount		= udf_mount,
132 	.kill_sb	= kill_block_super,
133 	.fs_flags	= FS_REQUIRES_DEV,
134 };
135 MODULE_ALIAS_FS("udf");
136 
137 static struct kmem_cache *udf_inode_cachep;
138 
139 static struct inode *udf_alloc_inode(struct super_block *sb)
140 {
141 	struct udf_inode_info *ei;
142 	ei = kmem_cache_alloc(udf_inode_cachep, GFP_KERNEL);
143 	if (!ei)
144 		return NULL;
145 
146 	ei->i_unique = 0;
147 	ei->i_lenExtents = 0;
148 	ei->i_next_alloc_block = 0;
149 	ei->i_next_alloc_goal = 0;
150 	ei->i_strat4096 = 0;
151 	init_rwsem(&ei->i_data_sem);
152 	ei->cached_extent.lstart = -1;
153 	spin_lock_init(&ei->i_extent_cache_lock);
154 
155 	return &ei->vfs_inode;
156 }
157 
158 static void udf_i_callback(struct rcu_head *head)
159 {
160 	struct inode *inode = container_of(head, struct inode, i_rcu);
161 	kmem_cache_free(udf_inode_cachep, UDF_I(inode));
162 }
163 
164 static void udf_destroy_inode(struct inode *inode)
165 {
166 	call_rcu(&inode->i_rcu, udf_i_callback);
167 }
168 
169 static void init_once(void *foo)
170 {
171 	struct udf_inode_info *ei = (struct udf_inode_info *)foo;
172 
173 	ei->i_ext.i_data = NULL;
174 	inode_init_once(&ei->vfs_inode);
175 }
176 
177 static int __init init_inodecache(void)
178 {
179 	udf_inode_cachep = kmem_cache_create("udf_inode_cache",
180 					     sizeof(struct udf_inode_info),
181 					     0, (SLAB_RECLAIM_ACCOUNT |
182 						 SLAB_MEM_SPREAD),
183 					     init_once);
184 	if (!udf_inode_cachep)
185 		return -ENOMEM;
186 	return 0;
187 }
188 
189 static void destroy_inodecache(void)
190 {
191 	/*
192 	 * Make sure all delayed rcu free inodes are flushed before we
193 	 * destroy cache.
194 	 */
195 	rcu_barrier();
196 	kmem_cache_destroy(udf_inode_cachep);
197 }
198 
199 /* Superblock operations */
200 static const struct super_operations udf_sb_ops = {
201 	.alloc_inode	= udf_alloc_inode,
202 	.destroy_inode	= udf_destroy_inode,
203 	.write_inode	= udf_write_inode,
204 	.evict_inode	= udf_evict_inode,
205 	.put_super	= udf_put_super,
206 	.sync_fs	= udf_sync_fs,
207 	.statfs		= udf_statfs,
208 	.remount_fs	= udf_remount_fs,
209 	.show_options	= udf_show_options,
210 };
211 
212 struct udf_options {
213 	unsigned char novrs;
214 	unsigned int blocksize;
215 	unsigned int session;
216 	unsigned int lastblock;
217 	unsigned int anchor;
218 	unsigned int volume;
219 	unsigned short partition;
220 	unsigned int fileset;
221 	unsigned int rootdir;
222 	unsigned int flags;
223 	umode_t umask;
224 	kgid_t gid;
225 	kuid_t uid;
226 	umode_t fmode;
227 	umode_t dmode;
228 	struct nls_table *nls_map;
229 };
230 
231 static int __init init_udf_fs(void)
232 {
233 	int err;
234 
235 	err = init_inodecache();
236 	if (err)
237 		goto out1;
238 	err = register_filesystem(&udf_fstype);
239 	if (err)
240 		goto out;
241 
242 	return 0;
243 
244 out:
245 	destroy_inodecache();
246 
247 out1:
248 	return err;
249 }
250 
251 static void __exit exit_udf_fs(void)
252 {
253 	unregister_filesystem(&udf_fstype);
254 	destroy_inodecache();
255 }
256 
257 module_init(init_udf_fs)
258 module_exit(exit_udf_fs)
259 
260 static int udf_sb_alloc_partition_maps(struct super_block *sb, u32 count)
261 {
262 	struct udf_sb_info *sbi = UDF_SB(sb);
263 
264 	sbi->s_partmaps = kcalloc(count, sizeof(struct udf_part_map),
265 				  GFP_KERNEL);
266 	if (!sbi->s_partmaps) {
267 		udf_err(sb, "Unable to allocate space for %d partition maps\n",
268 			count);
269 		sbi->s_partitions = 0;
270 		return -ENOMEM;
271 	}
272 
273 	sbi->s_partitions = count;
274 	return 0;
275 }
276 
277 static void udf_sb_free_bitmap(struct udf_bitmap *bitmap)
278 {
279 	int i;
280 	int nr_groups = bitmap->s_nr_groups;
281 	int size = sizeof(struct udf_bitmap) + (sizeof(struct buffer_head *) *
282 						nr_groups);
283 
284 	for (i = 0; i < nr_groups; i++)
285 		if (bitmap->s_block_bitmap[i])
286 			brelse(bitmap->s_block_bitmap[i]);
287 
288 	if (size <= PAGE_SIZE)
289 		kfree(bitmap);
290 	else
291 		vfree(bitmap);
292 }
293 
294 static void udf_free_partition(struct udf_part_map *map)
295 {
296 	int i;
297 	struct udf_meta_data *mdata;
298 
299 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
300 		iput(map->s_uspace.s_table);
301 	if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE)
302 		iput(map->s_fspace.s_table);
303 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
304 		udf_sb_free_bitmap(map->s_uspace.s_bitmap);
305 	if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP)
306 		udf_sb_free_bitmap(map->s_fspace.s_bitmap);
307 	if (map->s_partition_type == UDF_SPARABLE_MAP15)
308 		for (i = 0; i < 4; i++)
309 			brelse(map->s_type_specific.s_sparing.s_spar_map[i]);
310 	else if (map->s_partition_type == UDF_METADATA_MAP25) {
311 		mdata = &map->s_type_specific.s_metadata;
312 		iput(mdata->s_metadata_fe);
313 		mdata->s_metadata_fe = NULL;
314 
315 		iput(mdata->s_mirror_fe);
316 		mdata->s_mirror_fe = NULL;
317 
318 		iput(mdata->s_bitmap_fe);
319 		mdata->s_bitmap_fe = NULL;
320 	}
321 }
322 
323 static void udf_sb_free_partitions(struct super_block *sb)
324 {
325 	struct udf_sb_info *sbi = UDF_SB(sb);
326 	int i;
327 	if (sbi->s_partmaps == NULL)
328 		return;
329 	for (i = 0; i < sbi->s_partitions; i++)
330 		udf_free_partition(&sbi->s_partmaps[i]);
331 	kfree(sbi->s_partmaps);
332 	sbi->s_partmaps = NULL;
333 }
334 
335 static int udf_show_options(struct seq_file *seq, struct dentry *root)
336 {
337 	struct super_block *sb = root->d_sb;
338 	struct udf_sb_info *sbi = UDF_SB(sb);
339 
340 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT))
341 		seq_puts(seq, ",nostrict");
342 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_BLOCKSIZE_SET))
343 		seq_printf(seq, ",bs=%lu", sb->s_blocksize);
344 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
345 		seq_puts(seq, ",unhide");
346 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
347 		seq_puts(seq, ",undelete");
348 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_USE_AD_IN_ICB))
349 		seq_puts(seq, ",noadinicb");
350 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_USE_SHORT_AD))
351 		seq_puts(seq, ",shortad");
352 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_FORGET))
353 		seq_puts(seq, ",uid=forget");
354 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_IGNORE))
355 		seq_puts(seq, ",uid=ignore");
356 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_FORGET))
357 		seq_puts(seq, ",gid=forget");
358 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_IGNORE))
359 		seq_puts(seq, ",gid=ignore");
360 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET))
361 		seq_printf(seq, ",uid=%u", from_kuid(&init_user_ns, sbi->s_uid));
362 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET))
363 		seq_printf(seq, ",gid=%u", from_kgid(&init_user_ns, sbi->s_gid));
364 	if (sbi->s_umask != 0)
365 		seq_printf(seq, ",umask=%ho", sbi->s_umask);
366 	if (sbi->s_fmode != UDF_INVALID_MODE)
367 		seq_printf(seq, ",mode=%ho", sbi->s_fmode);
368 	if (sbi->s_dmode != UDF_INVALID_MODE)
369 		seq_printf(seq, ",dmode=%ho", sbi->s_dmode);
370 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_SESSION_SET))
371 		seq_printf(seq, ",session=%u", sbi->s_session);
372 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_LASTBLOCK_SET))
373 		seq_printf(seq, ",lastblock=%u", sbi->s_last_block);
374 	if (sbi->s_anchor != 0)
375 		seq_printf(seq, ",anchor=%u", sbi->s_anchor);
376 	/*
377 	 * volume, partition, fileset and rootdir seem to be ignored
378 	 * currently
379 	 */
380 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8))
381 		seq_puts(seq, ",utf8");
382 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP) && sbi->s_nls_map)
383 		seq_printf(seq, ",iocharset=%s", sbi->s_nls_map->charset);
384 
385 	return 0;
386 }
387 
388 /*
389  * udf_parse_options
390  *
391  * PURPOSE
392  *	Parse mount options.
393  *
394  * DESCRIPTION
395  *	The following mount options are supported:
396  *
397  *	gid=		Set the default group.
398  *	umask=		Set the default umask.
399  *	mode=		Set the default file permissions.
400  *	dmode=		Set the default directory permissions.
401  *	uid=		Set the default user.
402  *	bs=		Set the block size.
403  *	unhide		Show otherwise hidden files.
404  *	undelete	Show deleted files in lists.
405  *	adinicb		Embed data in the inode (default)
406  *	noadinicb	Don't embed data in the inode
407  *	shortad		Use short ad's
408  *	longad		Use long ad's (default)
409  *	nostrict	Unset strict conformance
410  *	iocharset=	Set the NLS character set
411  *
412  *	The remaining are for debugging and disaster recovery:
413  *
414  *	novrs		Skip volume sequence recognition
415  *
416  *	The following expect a offset from 0.
417  *
418  *	session=	Set the CDROM session (default= last session)
419  *	anchor=		Override standard anchor location. (default= 256)
420  *	volume=		Override the VolumeDesc location. (unused)
421  *	partition=	Override the PartitionDesc location. (unused)
422  *	lastblock=	Set the last block of the filesystem/
423  *
424  *	The following expect a offset from the partition root.
425  *
426  *	fileset=	Override the fileset block location. (unused)
427  *	rootdir=	Override the root directory location. (unused)
428  *		WARNING: overriding the rootdir to a non-directory may
429  *		yield highly unpredictable results.
430  *
431  * PRE-CONDITIONS
432  *	options		Pointer to mount options string.
433  *	uopts		Pointer to mount options variable.
434  *
435  * POST-CONDITIONS
436  *	<return>	1	Mount options parsed okay.
437  *	<return>	0	Error parsing mount options.
438  *
439  * HISTORY
440  *	July 1, 1997 - Andrew E. Mileski
441  *	Written, tested, and released.
442  */
443 
444 enum {
445 	Opt_novrs, Opt_nostrict, Opt_bs, Opt_unhide, Opt_undelete,
446 	Opt_noadinicb, Opt_adinicb, Opt_shortad, Opt_longad,
447 	Opt_gid, Opt_uid, Opt_umask, Opt_session, Opt_lastblock,
448 	Opt_anchor, Opt_volume, Opt_partition, Opt_fileset,
449 	Opt_rootdir, Opt_utf8, Opt_iocharset,
450 	Opt_err, Opt_uforget, Opt_uignore, Opt_gforget, Opt_gignore,
451 	Opt_fmode, Opt_dmode
452 };
453 
454 static const match_table_t tokens = {
455 	{Opt_novrs,	"novrs"},
456 	{Opt_nostrict,	"nostrict"},
457 	{Opt_bs,	"bs=%u"},
458 	{Opt_unhide,	"unhide"},
459 	{Opt_undelete,	"undelete"},
460 	{Opt_noadinicb,	"noadinicb"},
461 	{Opt_adinicb,	"adinicb"},
462 	{Opt_shortad,	"shortad"},
463 	{Opt_longad,	"longad"},
464 	{Opt_uforget,	"uid=forget"},
465 	{Opt_uignore,	"uid=ignore"},
466 	{Opt_gforget,	"gid=forget"},
467 	{Opt_gignore,	"gid=ignore"},
468 	{Opt_gid,	"gid=%u"},
469 	{Opt_uid,	"uid=%u"},
470 	{Opt_umask,	"umask=%o"},
471 	{Opt_session,	"session=%u"},
472 	{Opt_lastblock,	"lastblock=%u"},
473 	{Opt_anchor,	"anchor=%u"},
474 	{Opt_volume,	"volume=%u"},
475 	{Opt_partition,	"partition=%u"},
476 	{Opt_fileset,	"fileset=%u"},
477 	{Opt_rootdir,	"rootdir=%u"},
478 	{Opt_utf8,	"utf8"},
479 	{Opt_iocharset,	"iocharset=%s"},
480 	{Opt_fmode,     "mode=%o"},
481 	{Opt_dmode,     "dmode=%o"},
482 	{Opt_err,	NULL}
483 };
484 
485 static int udf_parse_options(char *options, struct udf_options *uopt,
486 			     bool remount)
487 {
488 	char *p;
489 	int option;
490 
491 	uopt->novrs = 0;
492 	uopt->partition = 0xFFFF;
493 	uopt->session = 0xFFFFFFFF;
494 	uopt->lastblock = 0;
495 	uopt->anchor = 0;
496 	uopt->volume = 0xFFFFFFFF;
497 	uopt->rootdir = 0xFFFFFFFF;
498 	uopt->fileset = 0xFFFFFFFF;
499 	uopt->nls_map = NULL;
500 
501 	if (!options)
502 		return 1;
503 
504 	while ((p = strsep(&options, ",")) != NULL) {
505 		substring_t args[MAX_OPT_ARGS];
506 		int token;
507 		unsigned n;
508 		if (!*p)
509 			continue;
510 
511 		token = match_token(p, tokens, args);
512 		switch (token) {
513 		case Opt_novrs:
514 			uopt->novrs = 1;
515 			break;
516 		case Opt_bs:
517 			if (match_int(&args[0], &option))
518 				return 0;
519 			n = option;
520 			if (n != 512 && n != 1024 && n != 2048 && n != 4096)
521 				return 0;
522 			uopt->blocksize = n;
523 			uopt->flags |= (1 << UDF_FLAG_BLOCKSIZE_SET);
524 			break;
525 		case Opt_unhide:
526 			uopt->flags |= (1 << UDF_FLAG_UNHIDE);
527 			break;
528 		case Opt_undelete:
529 			uopt->flags |= (1 << UDF_FLAG_UNDELETE);
530 			break;
531 		case Opt_noadinicb:
532 			uopt->flags &= ~(1 << UDF_FLAG_USE_AD_IN_ICB);
533 			break;
534 		case Opt_adinicb:
535 			uopt->flags |= (1 << UDF_FLAG_USE_AD_IN_ICB);
536 			break;
537 		case Opt_shortad:
538 			uopt->flags |= (1 << UDF_FLAG_USE_SHORT_AD);
539 			break;
540 		case Opt_longad:
541 			uopt->flags &= ~(1 << UDF_FLAG_USE_SHORT_AD);
542 			break;
543 		case Opt_gid:
544 			if (match_int(args, &option))
545 				return 0;
546 			uopt->gid = make_kgid(current_user_ns(), option);
547 			if (!gid_valid(uopt->gid))
548 				return 0;
549 			uopt->flags |= (1 << UDF_FLAG_GID_SET);
550 			break;
551 		case Opt_uid:
552 			if (match_int(args, &option))
553 				return 0;
554 			uopt->uid = make_kuid(current_user_ns(), option);
555 			if (!uid_valid(uopt->uid))
556 				return 0;
557 			uopt->flags |= (1 << UDF_FLAG_UID_SET);
558 			break;
559 		case Opt_umask:
560 			if (match_octal(args, &option))
561 				return 0;
562 			uopt->umask = option;
563 			break;
564 		case Opt_nostrict:
565 			uopt->flags &= ~(1 << UDF_FLAG_STRICT);
566 			break;
567 		case Opt_session:
568 			if (match_int(args, &option))
569 				return 0;
570 			uopt->session = option;
571 			if (!remount)
572 				uopt->flags |= (1 << UDF_FLAG_SESSION_SET);
573 			break;
574 		case Opt_lastblock:
575 			if (match_int(args, &option))
576 				return 0;
577 			uopt->lastblock = option;
578 			if (!remount)
579 				uopt->flags |= (1 << UDF_FLAG_LASTBLOCK_SET);
580 			break;
581 		case Opt_anchor:
582 			if (match_int(args, &option))
583 				return 0;
584 			uopt->anchor = option;
585 			break;
586 		case Opt_volume:
587 			if (match_int(args, &option))
588 				return 0;
589 			uopt->volume = option;
590 			break;
591 		case Opt_partition:
592 			if (match_int(args, &option))
593 				return 0;
594 			uopt->partition = option;
595 			break;
596 		case Opt_fileset:
597 			if (match_int(args, &option))
598 				return 0;
599 			uopt->fileset = option;
600 			break;
601 		case Opt_rootdir:
602 			if (match_int(args, &option))
603 				return 0;
604 			uopt->rootdir = option;
605 			break;
606 		case Opt_utf8:
607 			uopt->flags |= (1 << UDF_FLAG_UTF8);
608 			break;
609 #ifdef CONFIG_UDF_NLS
610 		case Opt_iocharset:
611 			uopt->nls_map = load_nls(args[0].from);
612 			uopt->flags |= (1 << UDF_FLAG_NLS_MAP);
613 			break;
614 #endif
615 		case Opt_uignore:
616 			uopt->flags |= (1 << UDF_FLAG_UID_IGNORE);
617 			break;
618 		case Opt_uforget:
619 			uopt->flags |= (1 << UDF_FLAG_UID_FORGET);
620 			break;
621 		case Opt_gignore:
622 			uopt->flags |= (1 << UDF_FLAG_GID_IGNORE);
623 			break;
624 		case Opt_gforget:
625 			uopt->flags |= (1 << UDF_FLAG_GID_FORGET);
626 			break;
627 		case Opt_fmode:
628 			if (match_octal(args, &option))
629 				return 0;
630 			uopt->fmode = option & 0777;
631 			break;
632 		case Opt_dmode:
633 			if (match_octal(args, &option))
634 				return 0;
635 			uopt->dmode = option & 0777;
636 			break;
637 		default:
638 			pr_err("bad mount option \"%s\" or missing value\n", p);
639 			return 0;
640 		}
641 	}
642 	return 1;
643 }
644 
645 static int udf_remount_fs(struct super_block *sb, int *flags, char *options)
646 {
647 	struct udf_options uopt;
648 	struct udf_sb_info *sbi = UDF_SB(sb);
649 	int error = 0;
650 	struct logicalVolIntegrityDescImpUse *lvidiu = udf_sb_lvidiu(sb);
651 
652 	sync_filesystem(sb);
653 	if (lvidiu) {
654 		int write_rev = le16_to_cpu(lvidiu->minUDFWriteRev);
655 		if (write_rev > UDF_MAX_WRITE_VERSION && !(*flags & MS_RDONLY))
656 			return -EACCES;
657 	}
658 
659 	uopt.flags = sbi->s_flags;
660 	uopt.uid   = sbi->s_uid;
661 	uopt.gid   = sbi->s_gid;
662 	uopt.umask = sbi->s_umask;
663 	uopt.fmode = sbi->s_fmode;
664 	uopt.dmode = sbi->s_dmode;
665 
666 	if (!udf_parse_options(options, &uopt, true))
667 		return -EINVAL;
668 
669 	write_lock(&sbi->s_cred_lock);
670 	sbi->s_flags = uopt.flags;
671 	sbi->s_uid   = uopt.uid;
672 	sbi->s_gid   = uopt.gid;
673 	sbi->s_umask = uopt.umask;
674 	sbi->s_fmode = uopt.fmode;
675 	sbi->s_dmode = uopt.dmode;
676 	write_unlock(&sbi->s_cred_lock);
677 
678 	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
679 		goto out_unlock;
680 
681 	if (*flags & MS_RDONLY)
682 		udf_close_lvid(sb);
683 	else
684 		udf_open_lvid(sb);
685 
686 out_unlock:
687 	return error;
688 }
689 
690 /* Check Volume Structure Descriptors (ECMA 167 2/9.1) */
691 /* We also check any "CD-ROM Volume Descriptor Set" (ECMA 167 2/8.3.1) */
692 static loff_t udf_check_vsd(struct super_block *sb)
693 {
694 	struct volStructDesc *vsd = NULL;
695 	loff_t sector = VSD_FIRST_SECTOR_OFFSET;
696 	int sectorsize;
697 	struct buffer_head *bh = NULL;
698 	int nsr02 = 0;
699 	int nsr03 = 0;
700 	struct udf_sb_info *sbi;
701 
702 	sbi = UDF_SB(sb);
703 	if (sb->s_blocksize < sizeof(struct volStructDesc))
704 		sectorsize = sizeof(struct volStructDesc);
705 	else
706 		sectorsize = sb->s_blocksize;
707 
708 	sector += (sbi->s_session << sb->s_blocksize_bits);
709 
710 	udf_debug("Starting at sector %u (%ld byte sectors)\n",
711 		  (unsigned int)(sector >> sb->s_blocksize_bits),
712 		  sb->s_blocksize);
713 	/* Process the sequence (if applicable). The hard limit on the sector
714 	 * offset is arbitrary, hopefully large enough so that all valid UDF
715 	 * filesystems will be recognised. There is no mention of an upper
716 	 * bound to the size of the volume recognition area in the standard.
717 	 *  The limit will prevent the code to read all the sectors of a
718 	 * specially crafted image (like a bluray disc full of CD001 sectors),
719 	 * potentially causing minutes or even hours of uninterruptible I/O
720 	 * activity. This actually happened with uninitialised SSD partitions
721 	 * (all 0xFF) before the check for the limit and all valid IDs were
722 	 * added */
723 	for (; !nsr02 && !nsr03 && sector < VSD_MAX_SECTOR_OFFSET;
724 	     sector += sectorsize) {
725 		/* Read a block */
726 		bh = udf_tread(sb, sector >> sb->s_blocksize_bits);
727 		if (!bh)
728 			break;
729 
730 		/* Look for ISO  descriptors */
731 		vsd = (struct volStructDesc *)(bh->b_data +
732 					      (sector & (sb->s_blocksize - 1)));
733 
734 		if (!strncmp(vsd->stdIdent, VSD_STD_ID_CD001,
735 				    VSD_STD_ID_LEN)) {
736 			switch (vsd->structType) {
737 			case 0:
738 				udf_debug("ISO9660 Boot Record found\n");
739 				break;
740 			case 1:
741 				udf_debug("ISO9660 Primary Volume Descriptor found\n");
742 				break;
743 			case 2:
744 				udf_debug("ISO9660 Supplementary Volume Descriptor found\n");
745 				break;
746 			case 3:
747 				udf_debug("ISO9660 Volume Partition Descriptor found\n");
748 				break;
749 			case 255:
750 				udf_debug("ISO9660 Volume Descriptor Set Terminator found\n");
751 				break;
752 			default:
753 				udf_debug("ISO9660 VRS (%u) found\n",
754 					  vsd->structType);
755 				break;
756 			}
757 		} else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BEA01,
758 				    VSD_STD_ID_LEN))
759 			; /* nothing */
760 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_TEA01,
761 				    VSD_STD_ID_LEN)) {
762 			brelse(bh);
763 			break;
764 		} else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR02,
765 				    VSD_STD_ID_LEN))
766 			nsr02 = sector;
767 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR03,
768 				    VSD_STD_ID_LEN))
769 			nsr03 = sector;
770 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BOOT2,
771 				    VSD_STD_ID_LEN))
772 			; /* nothing */
773 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_CDW02,
774 				    VSD_STD_ID_LEN))
775 			; /* nothing */
776 		else {
777 			/* invalid id : end of volume recognition area */
778 			brelse(bh);
779 			break;
780 		}
781 		brelse(bh);
782 	}
783 
784 	if (nsr03)
785 		return nsr03;
786 	else if (nsr02)
787 		return nsr02;
788 	else if (!bh && sector - (sbi->s_session << sb->s_blocksize_bits) ==
789 			VSD_FIRST_SECTOR_OFFSET)
790 		return -1;
791 	else
792 		return 0;
793 }
794 
795 static int udf_find_fileset(struct super_block *sb,
796 			    struct kernel_lb_addr *fileset,
797 			    struct kernel_lb_addr *root)
798 {
799 	struct buffer_head *bh = NULL;
800 	long lastblock;
801 	uint16_t ident;
802 	struct udf_sb_info *sbi;
803 
804 	if (fileset->logicalBlockNum != 0xFFFFFFFF ||
805 	    fileset->partitionReferenceNum != 0xFFFF) {
806 		bh = udf_read_ptagged(sb, fileset, 0, &ident);
807 
808 		if (!bh) {
809 			return 1;
810 		} else if (ident != TAG_IDENT_FSD) {
811 			brelse(bh);
812 			return 1;
813 		}
814 
815 	}
816 
817 	sbi = UDF_SB(sb);
818 	if (!bh) {
819 		/* Search backwards through the partitions */
820 		struct kernel_lb_addr newfileset;
821 
822 /* --> cvg: FIXME - is it reasonable? */
823 		return 1;
824 
825 		for (newfileset.partitionReferenceNum = sbi->s_partitions - 1;
826 		     (newfileset.partitionReferenceNum != 0xFFFF &&
827 		      fileset->logicalBlockNum == 0xFFFFFFFF &&
828 		      fileset->partitionReferenceNum == 0xFFFF);
829 		     newfileset.partitionReferenceNum--) {
830 			lastblock = sbi->s_partmaps
831 					[newfileset.partitionReferenceNum]
832 						.s_partition_len;
833 			newfileset.logicalBlockNum = 0;
834 
835 			do {
836 				bh = udf_read_ptagged(sb, &newfileset, 0,
837 						      &ident);
838 				if (!bh) {
839 					newfileset.logicalBlockNum++;
840 					continue;
841 				}
842 
843 				switch (ident) {
844 				case TAG_IDENT_SBD:
845 				{
846 					struct spaceBitmapDesc *sp;
847 					sp = (struct spaceBitmapDesc *)
848 								bh->b_data;
849 					newfileset.logicalBlockNum += 1 +
850 						((le32_to_cpu(sp->numOfBytes) +
851 						  sizeof(struct spaceBitmapDesc)
852 						  - 1) >> sb->s_blocksize_bits);
853 					brelse(bh);
854 					break;
855 				}
856 				case TAG_IDENT_FSD:
857 					*fileset = newfileset;
858 					break;
859 				default:
860 					newfileset.logicalBlockNum++;
861 					brelse(bh);
862 					bh = NULL;
863 					break;
864 				}
865 			} while (newfileset.logicalBlockNum < lastblock &&
866 				 fileset->logicalBlockNum == 0xFFFFFFFF &&
867 				 fileset->partitionReferenceNum == 0xFFFF);
868 		}
869 	}
870 
871 	if ((fileset->logicalBlockNum != 0xFFFFFFFF ||
872 	     fileset->partitionReferenceNum != 0xFFFF) && bh) {
873 		udf_debug("Fileset at block=%d, partition=%d\n",
874 			  fileset->logicalBlockNum,
875 			  fileset->partitionReferenceNum);
876 
877 		sbi->s_partition = fileset->partitionReferenceNum;
878 		udf_load_fileset(sb, bh, root);
879 		brelse(bh);
880 		return 0;
881 	}
882 	return 1;
883 }
884 
885 /*
886  * Load primary Volume Descriptor Sequence
887  *
888  * Return <0 on error, 0 on success. -EAGAIN is special meaning next sequence
889  * should be tried.
890  */
891 static int udf_load_pvoldesc(struct super_block *sb, sector_t block)
892 {
893 	struct primaryVolDesc *pvoldesc;
894 	struct ustr *instr, *outstr;
895 	struct buffer_head *bh;
896 	uint16_t ident;
897 	int ret = -ENOMEM;
898 
899 	instr = kmalloc(sizeof(struct ustr), GFP_NOFS);
900 	if (!instr)
901 		return -ENOMEM;
902 
903 	outstr = kmalloc(sizeof(struct ustr), GFP_NOFS);
904 	if (!outstr)
905 		goto out1;
906 
907 	bh = udf_read_tagged(sb, block, block, &ident);
908 	if (!bh) {
909 		ret = -EAGAIN;
910 		goto out2;
911 	}
912 
913 	if (ident != TAG_IDENT_PVD) {
914 		ret = -EIO;
915 		goto out_bh;
916 	}
917 
918 	pvoldesc = (struct primaryVolDesc *)bh->b_data;
919 
920 	if (udf_disk_stamp_to_time(&UDF_SB(sb)->s_record_time,
921 			      pvoldesc->recordingDateAndTime)) {
922 #ifdef UDFFS_DEBUG
923 		struct timestamp *ts = &pvoldesc->recordingDateAndTime;
924 		udf_debug("recording time %04u/%02u/%02u %02u:%02u (%x)\n",
925 			  le16_to_cpu(ts->year), ts->month, ts->day, ts->hour,
926 			  ts->minute, le16_to_cpu(ts->typeAndTimezone));
927 #endif
928 	}
929 
930 	if (!udf_build_ustr(instr, pvoldesc->volIdent, 32)) {
931 		ret = udf_CS0toUTF8(outstr, instr);
932 		if (ret < 0)
933 			goto out_bh;
934 
935 		strncpy(UDF_SB(sb)->s_volume_ident, outstr->u_name,
936 			outstr->u_len > 31 ? 31 : outstr->u_len);
937 		udf_debug("volIdent[] = '%s'\n", UDF_SB(sb)->s_volume_ident);
938 	}
939 
940 	if (!udf_build_ustr(instr, pvoldesc->volSetIdent, 128)) {
941 		ret = udf_CS0toUTF8(outstr, instr);
942 		if (ret < 0)
943 			goto out_bh;
944 
945 		udf_debug("volSetIdent[] = '%s'\n", outstr->u_name);
946 	}
947 
948 	ret = 0;
949 out_bh:
950 	brelse(bh);
951 out2:
952 	kfree(outstr);
953 out1:
954 	kfree(instr);
955 	return ret;
956 }
957 
958 struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
959 					u32 meta_file_loc, u32 partition_num)
960 {
961 	struct kernel_lb_addr addr;
962 	struct inode *metadata_fe;
963 
964 	addr.logicalBlockNum = meta_file_loc;
965 	addr.partitionReferenceNum = partition_num;
966 
967 	metadata_fe = udf_iget_special(sb, &addr);
968 
969 	if (IS_ERR(metadata_fe)) {
970 		udf_warn(sb, "metadata inode efe not found\n");
971 		return metadata_fe;
972 	}
973 	if (UDF_I(metadata_fe)->i_alloc_type != ICBTAG_FLAG_AD_SHORT) {
974 		udf_warn(sb, "metadata inode efe does not have short allocation descriptors!\n");
975 		iput(metadata_fe);
976 		return ERR_PTR(-EIO);
977 	}
978 
979 	return metadata_fe;
980 }
981 
982 static int udf_load_metadata_files(struct super_block *sb, int partition)
983 {
984 	struct udf_sb_info *sbi = UDF_SB(sb);
985 	struct udf_part_map *map;
986 	struct udf_meta_data *mdata;
987 	struct kernel_lb_addr addr;
988 	struct inode *fe;
989 
990 	map = &sbi->s_partmaps[partition];
991 	mdata = &map->s_type_specific.s_metadata;
992 
993 	/* metadata address */
994 	udf_debug("Metadata file location: block = %d part = %d\n",
995 		  mdata->s_meta_file_loc, map->s_partition_num);
996 
997 	fe = udf_find_metadata_inode_efe(sb, mdata->s_meta_file_loc,
998 					 map->s_partition_num);
999 	if (IS_ERR(fe)) {
1000 		/* mirror file entry */
1001 		udf_debug("Mirror metadata file location: block = %d part = %d\n",
1002 			  mdata->s_mirror_file_loc, map->s_partition_num);
1003 
1004 		fe = udf_find_metadata_inode_efe(sb, mdata->s_mirror_file_loc,
1005 						 map->s_partition_num);
1006 
1007 		if (IS_ERR(fe)) {
1008 			udf_err(sb, "Both metadata and mirror metadata inode efe can not found\n");
1009 			return PTR_ERR(fe);
1010 		}
1011 		mdata->s_mirror_fe = fe;
1012 	} else
1013 		mdata->s_metadata_fe = fe;
1014 
1015 
1016 	/*
1017 	 * bitmap file entry
1018 	 * Note:
1019 	 * Load only if bitmap file location differs from 0xFFFFFFFF (DCN-5102)
1020 	*/
1021 	if (mdata->s_bitmap_file_loc != 0xFFFFFFFF) {
1022 		addr.logicalBlockNum = mdata->s_bitmap_file_loc;
1023 		addr.partitionReferenceNum = map->s_partition_num;
1024 
1025 		udf_debug("Bitmap file location: block = %d part = %d\n",
1026 			  addr.logicalBlockNum, addr.partitionReferenceNum);
1027 
1028 		fe = udf_iget_special(sb, &addr);
1029 		if (IS_ERR(fe)) {
1030 			if (sb->s_flags & MS_RDONLY)
1031 				udf_warn(sb, "bitmap inode efe not found but it's ok since the disc is mounted read-only\n");
1032 			else {
1033 				udf_err(sb, "bitmap inode efe not found and attempted read-write mount\n");
1034 				return PTR_ERR(fe);
1035 			}
1036 		} else
1037 			mdata->s_bitmap_fe = fe;
1038 	}
1039 
1040 	udf_debug("udf_load_metadata_files Ok\n");
1041 	return 0;
1042 }
1043 
1044 static void udf_load_fileset(struct super_block *sb, struct buffer_head *bh,
1045 			     struct kernel_lb_addr *root)
1046 {
1047 	struct fileSetDesc *fset;
1048 
1049 	fset = (struct fileSetDesc *)bh->b_data;
1050 
1051 	*root = lelb_to_cpu(fset->rootDirectoryICB.extLocation);
1052 
1053 	UDF_SB(sb)->s_serial_number = le16_to_cpu(fset->descTag.tagSerialNum);
1054 
1055 	udf_debug("Rootdir at block=%d, partition=%d\n",
1056 		  root->logicalBlockNum, root->partitionReferenceNum);
1057 }
1058 
1059 int udf_compute_nr_groups(struct super_block *sb, u32 partition)
1060 {
1061 	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
1062 	return DIV_ROUND_UP(map->s_partition_len +
1063 			    (sizeof(struct spaceBitmapDesc) << 3),
1064 			    sb->s_blocksize * 8);
1065 }
1066 
1067 static struct udf_bitmap *udf_sb_alloc_bitmap(struct super_block *sb, u32 index)
1068 {
1069 	struct udf_bitmap *bitmap;
1070 	int nr_groups;
1071 	int size;
1072 
1073 	nr_groups = udf_compute_nr_groups(sb, index);
1074 	size = sizeof(struct udf_bitmap) +
1075 		(sizeof(struct buffer_head *) * nr_groups);
1076 
1077 	if (size <= PAGE_SIZE)
1078 		bitmap = kzalloc(size, GFP_KERNEL);
1079 	else
1080 		bitmap = vzalloc(size); /* TODO: get rid of vzalloc */
1081 
1082 	if (bitmap == NULL)
1083 		return NULL;
1084 
1085 	bitmap->s_nr_groups = nr_groups;
1086 	return bitmap;
1087 }
1088 
1089 static int udf_fill_partdesc_info(struct super_block *sb,
1090 		struct partitionDesc *p, int p_index)
1091 {
1092 	struct udf_part_map *map;
1093 	struct udf_sb_info *sbi = UDF_SB(sb);
1094 	struct partitionHeaderDesc *phd;
1095 
1096 	map = &sbi->s_partmaps[p_index];
1097 
1098 	map->s_partition_len = le32_to_cpu(p->partitionLength); /* blocks */
1099 	map->s_partition_root = le32_to_cpu(p->partitionStartingLocation);
1100 
1101 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_READ_ONLY))
1102 		map->s_partition_flags |= UDF_PART_FLAG_READ_ONLY;
1103 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_WRITE_ONCE))
1104 		map->s_partition_flags |= UDF_PART_FLAG_WRITE_ONCE;
1105 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_REWRITABLE))
1106 		map->s_partition_flags |= UDF_PART_FLAG_REWRITABLE;
1107 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_OVERWRITABLE))
1108 		map->s_partition_flags |= UDF_PART_FLAG_OVERWRITABLE;
1109 
1110 	udf_debug("Partition (%d type %x) starts at physical %d, block length %d\n",
1111 		  p_index, map->s_partition_type,
1112 		  map->s_partition_root, map->s_partition_len);
1113 
1114 	if (strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR02) &&
1115 	    strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR03))
1116 		return 0;
1117 
1118 	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1119 	if (phd->unallocSpaceTable.extLength) {
1120 		struct kernel_lb_addr loc = {
1121 			.logicalBlockNum = le32_to_cpu(
1122 				phd->unallocSpaceTable.extPosition),
1123 			.partitionReferenceNum = p_index,
1124 		};
1125 		struct inode *inode;
1126 
1127 		inode = udf_iget_special(sb, &loc);
1128 		if (IS_ERR(inode)) {
1129 			udf_debug("cannot load unallocSpaceTable (part %d)\n",
1130 				  p_index);
1131 			return PTR_ERR(inode);
1132 		}
1133 		map->s_uspace.s_table = inode;
1134 		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_TABLE;
1135 		udf_debug("unallocSpaceTable (part %d) @ %ld\n",
1136 			  p_index, map->s_uspace.s_table->i_ino);
1137 	}
1138 
1139 	if (phd->unallocSpaceBitmap.extLength) {
1140 		struct udf_bitmap *bitmap = udf_sb_alloc_bitmap(sb, p_index);
1141 		if (!bitmap)
1142 			return -ENOMEM;
1143 		map->s_uspace.s_bitmap = bitmap;
1144 		bitmap->s_extPosition = le32_to_cpu(
1145 				phd->unallocSpaceBitmap.extPosition);
1146 		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_BITMAP;
1147 		udf_debug("unallocSpaceBitmap (part %d) @ %d\n",
1148 			  p_index, bitmap->s_extPosition);
1149 	}
1150 
1151 	if (phd->partitionIntegrityTable.extLength)
1152 		udf_debug("partitionIntegrityTable (part %d)\n", p_index);
1153 
1154 	if (phd->freedSpaceTable.extLength) {
1155 		struct kernel_lb_addr loc = {
1156 			.logicalBlockNum = le32_to_cpu(
1157 				phd->freedSpaceTable.extPosition),
1158 			.partitionReferenceNum = p_index,
1159 		};
1160 		struct inode *inode;
1161 
1162 		inode = udf_iget_special(sb, &loc);
1163 		if (IS_ERR(inode)) {
1164 			udf_debug("cannot load freedSpaceTable (part %d)\n",
1165 				  p_index);
1166 			return PTR_ERR(inode);
1167 		}
1168 		map->s_fspace.s_table = inode;
1169 		map->s_partition_flags |= UDF_PART_FLAG_FREED_TABLE;
1170 		udf_debug("freedSpaceTable (part %d) @ %ld\n",
1171 			  p_index, map->s_fspace.s_table->i_ino);
1172 	}
1173 
1174 	if (phd->freedSpaceBitmap.extLength) {
1175 		struct udf_bitmap *bitmap = udf_sb_alloc_bitmap(sb, p_index);
1176 		if (!bitmap)
1177 			return -ENOMEM;
1178 		map->s_fspace.s_bitmap = bitmap;
1179 		bitmap->s_extPosition = le32_to_cpu(
1180 				phd->freedSpaceBitmap.extPosition);
1181 		map->s_partition_flags |= UDF_PART_FLAG_FREED_BITMAP;
1182 		udf_debug("freedSpaceBitmap (part %d) @ %d\n",
1183 			  p_index, bitmap->s_extPosition);
1184 	}
1185 	return 0;
1186 }
1187 
1188 static void udf_find_vat_block(struct super_block *sb, int p_index,
1189 			       int type1_index, sector_t start_block)
1190 {
1191 	struct udf_sb_info *sbi = UDF_SB(sb);
1192 	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1193 	sector_t vat_block;
1194 	struct kernel_lb_addr ino;
1195 	struct inode *inode;
1196 
1197 	/*
1198 	 * VAT file entry is in the last recorded block. Some broken disks have
1199 	 * it a few blocks before so try a bit harder...
1200 	 */
1201 	ino.partitionReferenceNum = type1_index;
1202 	for (vat_block = start_block;
1203 	     vat_block >= map->s_partition_root &&
1204 	     vat_block >= start_block - 3; vat_block--) {
1205 		ino.logicalBlockNum = vat_block - map->s_partition_root;
1206 		inode = udf_iget_special(sb, &ino);
1207 		if (!IS_ERR(inode)) {
1208 			sbi->s_vat_inode = inode;
1209 			break;
1210 		}
1211 	}
1212 }
1213 
1214 static int udf_load_vat(struct super_block *sb, int p_index, int type1_index)
1215 {
1216 	struct udf_sb_info *sbi = UDF_SB(sb);
1217 	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1218 	struct buffer_head *bh = NULL;
1219 	struct udf_inode_info *vati;
1220 	uint32_t pos;
1221 	struct virtualAllocationTable20 *vat20;
1222 	sector_t blocks = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
1223 
1224 	udf_find_vat_block(sb, p_index, type1_index, sbi->s_last_block);
1225 	if (!sbi->s_vat_inode &&
1226 	    sbi->s_last_block != blocks - 1) {
1227 		pr_notice("Failed to read VAT inode from the last recorded block (%lu), retrying with the last block of the device (%lu).\n",
1228 			  (unsigned long)sbi->s_last_block,
1229 			  (unsigned long)blocks - 1);
1230 		udf_find_vat_block(sb, p_index, type1_index, blocks - 1);
1231 	}
1232 	if (!sbi->s_vat_inode)
1233 		return -EIO;
1234 
1235 	if (map->s_partition_type == UDF_VIRTUAL_MAP15) {
1236 		map->s_type_specific.s_virtual.s_start_offset = 0;
1237 		map->s_type_specific.s_virtual.s_num_entries =
1238 			(sbi->s_vat_inode->i_size - 36) >> 2;
1239 	} else if (map->s_partition_type == UDF_VIRTUAL_MAP20) {
1240 		vati = UDF_I(sbi->s_vat_inode);
1241 		if (vati->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1242 			pos = udf_block_map(sbi->s_vat_inode, 0);
1243 			bh = sb_bread(sb, pos);
1244 			if (!bh)
1245 				return -EIO;
1246 			vat20 = (struct virtualAllocationTable20 *)bh->b_data;
1247 		} else {
1248 			vat20 = (struct virtualAllocationTable20 *)
1249 							vati->i_ext.i_data;
1250 		}
1251 
1252 		map->s_type_specific.s_virtual.s_start_offset =
1253 			le16_to_cpu(vat20->lengthHeader);
1254 		map->s_type_specific.s_virtual.s_num_entries =
1255 			(sbi->s_vat_inode->i_size -
1256 				map->s_type_specific.s_virtual.
1257 					s_start_offset) >> 2;
1258 		brelse(bh);
1259 	}
1260 	return 0;
1261 }
1262 
1263 /*
1264  * Load partition descriptor block
1265  *
1266  * Returns <0 on error, 0 on success, -EAGAIN is special - try next descriptor
1267  * sequence.
1268  */
1269 static int udf_load_partdesc(struct super_block *sb, sector_t block)
1270 {
1271 	struct buffer_head *bh;
1272 	struct partitionDesc *p;
1273 	struct udf_part_map *map;
1274 	struct udf_sb_info *sbi = UDF_SB(sb);
1275 	int i, type1_idx;
1276 	uint16_t partitionNumber;
1277 	uint16_t ident;
1278 	int ret;
1279 
1280 	bh = udf_read_tagged(sb, block, block, &ident);
1281 	if (!bh)
1282 		return -EAGAIN;
1283 	if (ident != TAG_IDENT_PD) {
1284 		ret = 0;
1285 		goto out_bh;
1286 	}
1287 
1288 	p = (struct partitionDesc *)bh->b_data;
1289 	partitionNumber = le16_to_cpu(p->partitionNumber);
1290 
1291 	/* First scan for TYPE1, SPARABLE and METADATA partitions */
1292 	for (i = 0; i < sbi->s_partitions; i++) {
1293 		map = &sbi->s_partmaps[i];
1294 		udf_debug("Searching map: (%d == %d)\n",
1295 			  map->s_partition_num, partitionNumber);
1296 		if (map->s_partition_num == partitionNumber &&
1297 		    (map->s_partition_type == UDF_TYPE1_MAP15 ||
1298 		     map->s_partition_type == UDF_SPARABLE_MAP15))
1299 			break;
1300 	}
1301 
1302 	if (i >= sbi->s_partitions) {
1303 		udf_debug("Partition (%d) not found in partition map\n",
1304 			  partitionNumber);
1305 		ret = 0;
1306 		goto out_bh;
1307 	}
1308 
1309 	ret = udf_fill_partdesc_info(sb, p, i);
1310 	if (ret < 0)
1311 		goto out_bh;
1312 
1313 	/*
1314 	 * Now rescan for VIRTUAL or METADATA partitions when SPARABLE and
1315 	 * PHYSICAL partitions are already set up
1316 	 */
1317 	type1_idx = i;
1318 #ifdef UDFFS_DEBUG
1319 	map = NULL; /* supress 'maybe used uninitialized' warning */
1320 #endif
1321 	for (i = 0; i < sbi->s_partitions; i++) {
1322 		map = &sbi->s_partmaps[i];
1323 
1324 		if (map->s_partition_num == partitionNumber &&
1325 		    (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1326 		     map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1327 		     map->s_partition_type == UDF_METADATA_MAP25))
1328 			break;
1329 	}
1330 
1331 	if (i >= sbi->s_partitions) {
1332 		ret = 0;
1333 		goto out_bh;
1334 	}
1335 
1336 	ret = udf_fill_partdesc_info(sb, p, i);
1337 	if (ret < 0)
1338 		goto out_bh;
1339 
1340 	if (map->s_partition_type == UDF_METADATA_MAP25) {
1341 		ret = udf_load_metadata_files(sb, i);
1342 		if (ret < 0) {
1343 			udf_err(sb, "error loading MetaData partition map %d\n",
1344 				i);
1345 			goto out_bh;
1346 		}
1347 	} else {
1348 		/*
1349 		 * If we have a partition with virtual map, we don't handle
1350 		 * writing to it (we overwrite blocks instead of relocating
1351 		 * them).
1352 		 */
1353 		if (!(sb->s_flags & MS_RDONLY)) {
1354 			ret = -EACCES;
1355 			goto out_bh;
1356 		}
1357 		ret = udf_load_vat(sb, i, type1_idx);
1358 		if (ret < 0)
1359 			goto out_bh;
1360 	}
1361 	ret = 0;
1362 out_bh:
1363 	/* In case loading failed, we handle cleanup in udf_fill_super */
1364 	brelse(bh);
1365 	return ret;
1366 }
1367 
1368 static int udf_load_sparable_map(struct super_block *sb,
1369 				 struct udf_part_map *map,
1370 				 struct sparablePartitionMap *spm)
1371 {
1372 	uint32_t loc;
1373 	uint16_t ident;
1374 	struct sparingTable *st;
1375 	struct udf_sparing_data *sdata = &map->s_type_specific.s_sparing;
1376 	int i;
1377 	struct buffer_head *bh;
1378 
1379 	map->s_partition_type = UDF_SPARABLE_MAP15;
1380 	sdata->s_packet_len = le16_to_cpu(spm->packetLength);
1381 	if (!is_power_of_2(sdata->s_packet_len)) {
1382 		udf_err(sb, "error loading logical volume descriptor: "
1383 			"Invalid packet length %u\n",
1384 			(unsigned)sdata->s_packet_len);
1385 		return -EIO;
1386 	}
1387 	if (spm->numSparingTables > 4) {
1388 		udf_err(sb, "error loading logical volume descriptor: "
1389 			"Too many sparing tables (%d)\n",
1390 			(int)spm->numSparingTables);
1391 		return -EIO;
1392 	}
1393 
1394 	for (i = 0; i < spm->numSparingTables; i++) {
1395 		loc = le32_to_cpu(spm->locSparingTable[i]);
1396 		bh = udf_read_tagged(sb, loc, loc, &ident);
1397 		if (!bh)
1398 			continue;
1399 
1400 		st = (struct sparingTable *)bh->b_data;
1401 		if (ident != 0 ||
1402 		    strncmp(st->sparingIdent.ident, UDF_ID_SPARING,
1403 			    strlen(UDF_ID_SPARING)) ||
1404 		    sizeof(*st) + le16_to_cpu(st->reallocationTableLen) >
1405 							sb->s_blocksize) {
1406 			brelse(bh);
1407 			continue;
1408 		}
1409 
1410 		sdata->s_spar_map[i] = bh;
1411 	}
1412 	map->s_partition_func = udf_get_pblock_spar15;
1413 	return 0;
1414 }
1415 
1416 static int udf_load_logicalvol(struct super_block *sb, sector_t block,
1417 			       struct kernel_lb_addr *fileset)
1418 {
1419 	struct logicalVolDesc *lvd;
1420 	int i, offset;
1421 	uint8_t type;
1422 	struct udf_sb_info *sbi = UDF_SB(sb);
1423 	struct genericPartitionMap *gpm;
1424 	uint16_t ident;
1425 	struct buffer_head *bh;
1426 	unsigned int table_len;
1427 	int ret;
1428 
1429 	bh = udf_read_tagged(sb, block, block, &ident);
1430 	if (!bh)
1431 		return -EAGAIN;
1432 	BUG_ON(ident != TAG_IDENT_LVD);
1433 	lvd = (struct logicalVolDesc *)bh->b_data;
1434 	table_len = le32_to_cpu(lvd->mapTableLength);
1435 	if (table_len > sb->s_blocksize - sizeof(*lvd)) {
1436 		udf_err(sb, "error loading logical volume descriptor: "
1437 			"Partition table too long (%u > %lu)\n", table_len,
1438 			sb->s_blocksize - sizeof(*lvd));
1439 		ret = -EIO;
1440 		goto out_bh;
1441 	}
1442 
1443 	ret = udf_sb_alloc_partition_maps(sb, le32_to_cpu(lvd->numPartitionMaps));
1444 	if (ret)
1445 		goto out_bh;
1446 
1447 	for (i = 0, offset = 0;
1448 	     i < sbi->s_partitions && offset < table_len;
1449 	     i++, offset += gpm->partitionMapLength) {
1450 		struct udf_part_map *map = &sbi->s_partmaps[i];
1451 		gpm = (struct genericPartitionMap *)
1452 				&(lvd->partitionMaps[offset]);
1453 		type = gpm->partitionMapType;
1454 		if (type == 1) {
1455 			struct genericPartitionMap1 *gpm1 =
1456 				(struct genericPartitionMap1 *)gpm;
1457 			map->s_partition_type = UDF_TYPE1_MAP15;
1458 			map->s_volumeseqnum = le16_to_cpu(gpm1->volSeqNum);
1459 			map->s_partition_num = le16_to_cpu(gpm1->partitionNum);
1460 			map->s_partition_func = NULL;
1461 		} else if (type == 2) {
1462 			struct udfPartitionMap2 *upm2 =
1463 						(struct udfPartitionMap2 *)gpm;
1464 			if (!strncmp(upm2->partIdent.ident, UDF_ID_VIRTUAL,
1465 						strlen(UDF_ID_VIRTUAL))) {
1466 				u16 suf =
1467 					le16_to_cpu(((__le16 *)upm2->partIdent.
1468 							identSuffix)[0]);
1469 				if (suf < 0x0200) {
1470 					map->s_partition_type =
1471 							UDF_VIRTUAL_MAP15;
1472 					map->s_partition_func =
1473 							udf_get_pblock_virt15;
1474 				} else {
1475 					map->s_partition_type =
1476 							UDF_VIRTUAL_MAP20;
1477 					map->s_partition_func =
1478 							udf_get_pblock_virt20;
1479 				}
1480 			} else if (!strncmp(upm2->partIdent.ident,
1481 						UDF_ID_SPARABLE,
1482 						strlen(UDF_ID_SPARABLE))) {
1483 				ret = udf_load_sparable_map(sb, map,
1484 					(struct sparablePartitionMap *)gpm);
1485 				if (ret < 0)
1486 					goto out_bh;
1487 			} else if (!strncmp(upm2->partIdent.ident,
1488 						UDF_ID_METADATA,
1489 						strlen(UDF_ID_METADATA))) {
1490 				struct udf_meta_data *mdata =
1491 					&map->s_type_specific.s_metadata;
1492 				struct metadataPartitionMap *mdm =
1493 						(struct metadataPartitionMap *)
1494 						&(lvd->partitionMaps[offset]);
1495 				udf_debug("Parsing Logical vol part %d type %d  id=%s\n",
1496 					  i, type, UDF_ID_METADATA);
1497 
1498 				map->s_partition_type = UDF_METADATA_MAP25;
1499 				map->s_partition_func = udf_get_pblock_meta25;
1500 
1501 				mdata->s_meta_file_loc   =
1502 					le32_to_cpu(mdm->metadataFileLoc);
1503 				mdata->s_mirror_file_loc =
1504 					le32_to_cpu(mdm->metadataMirrorFileLoc);
1505 				mdata->s_bitmap_file_loc =
1506 					le32_to_cpu(mdm->metadataBitmapFileLoc);
1507 				mdata->s_alloc_unit_size =
1508 					le32_to_cpu(mdm->allocUnitSize);
1509 				mdata->s_align_unit_size =
1510 					le16_to_cpu(mdm->alignUnitSize);
1511 				if (mdm->flags & 0x01)
1512 					mdata->s_flags |= MF_DUPLICATE_MD;
1513 
1514 				udf_debug("Metadata Ident suffix=0x%x\n",
1515 					  le16_to_cpu(*(__le16 *)
1516 						      mdm->partIdent.identSuffix));
1517 				udf_debug("Metadata part num=%d\n",
1518 					  le16_to_cpu(mdm->partitionNum));
1519 				udf_debug("Metadata part alloc unit size=%d\n",
1520 					  le32_to_cpu(mdm->allocUnitSize));
1521 				udf_debug("Metadata file loc=%d\n",
1522 					  le32_to_cpu(mdm->metadataFileLoc));
1523 				udf_debug("Mirror file loc=%d\n",
1524 					  le32_to_cpu(mdm->metadataMirrorFileLoc));
1525 				udf_debug("Bitmap file loc=%d\n",
1526 					  le32_to_cpu(mdm->metadataBitmapFileLoc));
1527 				udf_debug("Flags: %d %d\n",
1528 					  mdata->s_flags, mdm->flags);
1529 			} else {
1530 				udf_debug("Unknown ident: %s\n",
1531 					  upm2->partIdent.ident);
1532 				continue;
1533 			}
1534 			map->s_volumeseqnum = le16_to_cpu(upm2->volSeqNum);
1535 			map->s_partition_num = le16_to_cpu(upm2->partitionNum);
1536 		}
1537 		udf_debug("Partition (%d:%d) type %d on volume %d\n",
1538 			  i, map->s_partition_num, type, map->s_volumeseqnum);
1539 	}
1540 
1541 	if (fileset) {
1542 		struct long_ad *la = (struct long_ad *)&(lvd->logicalVolContentsUse[0]);
1543 
1544 		*fileset = lelb_to_cpu(la->extLocation);
1545 		udf_debug("FileSet found in LogicalVolDesc at block=%d, partition=%d\n",
1546 			  fileset->logicalBlockNum,
1547 			  fileset->partitionReferenceNum);
1548 	}
1549 	if (lvd->integritySeqExt.extLength)
1550 		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
1551 	ret = 0;
1552 out_bh:
1553 	brelse(bh);
1554 	return ret;
1555 }
1556 
1557 /*
1558  * udf_load_logicalvolint
1559  *
1560  */
1561 static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_ad loc)
1562 {
1563 	struct buffer_head *bh = NULL;
1564 	uint16_t ident;
1565 	struct udf_sb_info *sbi = UDF_SB(sb);
1566 	struct logicalVolIntegrityDesc *lvid;
1567 
1568 	while (loc.extLength > 0 &&
1569 	       (bh = udf_read_tagged(sb, loc.extLocation,
1570 				     loc.extLocation, &ident)) &&
1571 	       ident == TAG_IDENT_LVID) {
1572 		sbi->s_lvid_bh = bh;
1573 		lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
1574 
1575 		if (lvid->nextIntegrityExt.extLength)
1576 			udf_load_logicalvolint(sb,
1577 				leea_to_cpu(lvid->nextIntegrityExt));
1578 
1579 		if (sbi->s_lvid_bh != bh)
1580 			brelse(bh);
1581 		loc.extLength -= sb->s_blocksize;
1582 		loc.extLocation++;
1583 	}
1584 	if (sbi->s_lvid_bh != bh)
1585 		brelse(bh);
1586 }
1587 
1588 /*
1589  * Process a main/reserve volume descriptor sequence.
1590  *   @block		First block of first extent of the sequence.
1591  *   @lastblock		Lastblock of first extent of the sequence.
1592  *   @fileset		There we store extent containing root fileset
1593  *
1594  * Returns <0 on error, 0 on success. -EAGAIN is special - try next descriptor
1595  * sequence
1596  */
1597 static noinline int udf_process_sequence(
1598 		struct super_block *sb,
1599 		sector_t block, sector_t lastblock,
1600 		struct kernel_lb_addr *fileset)
1601 {
1602 	struct buffer_head *bh = NULL;
1603 	struct udf_vds_record vds[VDS_POS_LENGTH];
1604 	struct udf_vds_record *curr;
1605 	struct generic_desc *gd;
1606 	struct volDescPtr *vdp;
1607 	bool done = false;
1608 	uint32_t vdsn;
1609 	uint16_t ident;
1610 	long next_s = 0, next_e = 0;
1611 	int ret;
1612 
1613 	memset(vds, 0, sizeof(struct udf_vds_record) * VDS_POS_LENGTH);
1614 
1615 	/*
1616 	 * Read the main descriptor sequence and find which descriptors
1617 	 * are in it.
1618 	 */
1619 	for (; (!done && block <= lastblock); block++) {
1620 
1621 		bh = udf_read_tagged(sb, block, block, &ident);
1622 		if (!bh) {
1623 			udf_err(sb,
1624 				"Block %llu of volume descriptor sequence is corrupted or we could not read it\n",
1625 				(unsigned long long)block);
1626 			return -EAGAIN;
1627 		}
1628 
1629 		/* Process each descriptor (ISO 13346 3/8.3-8.4) */
1630 		gd = (struct generic_desc *)bh->b_data;
1631 		vdsn = le32_to_cpu(gd->volDescSeqNum);
1632 		switch (ident) {
1633 		case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1634 			curr = &vds[VDS_POS_PRIMARY_VOL_DESC];
1635 			if (vdsn >= curr->volDescSeqNum) {
1636 				curr->volDescSeqNum = vdsn;
1637 				curr->block = block;
1638 			}
1639 			break;
1640 		case TAG_IDENT_VDP: /* ISO 13346 3/10.3 */
1641 			curr = &vds[VDS_POS_VOL_DESC_PTR];
1642 			if (vdsn >= curr->volDescSeqNum) {
1643 				curr->volDescSeqNum = vdsn;
1644 				curr->block = block;
1645 
1646 				vdp = (struct volDescPtr *)bh->b_data;
1647 				next_s = le32_to_cpu(
1648 					vdp->nextVolDescSeqExt.extLocation);
1649 				next_e = le32_to_cpu(
1650 					vdp->nextVolDescSeqExt.extLength);
1651 				next_e = next_e >> sb->s_blocksize_bits;
1652 				next_e += next_s;
1653 			}
1654 			break;
1655 		case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1656 			curr = &vds[VDS_POS_IMP_USE_VOL_DESC];
1657 			if (vdsn >= curr->volDescSeqNum) {
1658 				curr->volDescSeqNum = vdsn;
1659 				curr->block = block;
1660 			}
1661 			break;
1662 		case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1663 			curr = &vds[VDS_POS_PARTITION_DESC];
1664 			if (!curr->block)
1665 				curr->block = block;
1666 			break;
1667 		case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1668 			curr = &vds[VDS_POS_LOGICAL_VOL_DESC];
1669 			if (vdsn >= curr->volDescSeqNum) {
1670 				curr->volDescSeqNum = vdsn;
1671 				curr->block = block;
1672 			}
1673 			break;
1674 		case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1675 			curr = &vds[VDS_POS_UNALLOC_SPACE_DESC];
1676 			if (vdsn >= curr->volDescSeqNum) {
1677 				curr->volDescSeqNum = vdsn;
1678 				curr->block = block;
1679 			}
1680 			break;
1681 		case TAG_IDENT_TD: /* ISO 13346 3/10.9 */
1682 			vds[VDS_POS_TERMINATING_DESC].block = block;
1683 			if (next_e) {
1684 				block = next_s;
1685 				lastblock = next_e;
1686 				next_s = next_e = 0;
1687 			} else
1688 				done = true;
1689 			break;
1690 		}
1691 		brelse(bh);
1692 	}
1693 	/*
1694 	 * Now read interesting descriptors again and process them
1695 	 * in a suitable order
1696 	 */
1697 	if (!vds[VDS_POS_PRIMARY_VOL_DESC].block) {
1698 		udf_err(sb, "Primary Volume Descriptor not found!\n");
1699 		return -EAGAIN;
1700 	}
1701 	ret = udf_load_pvoldesc(sb, vds[VDS_POS_PRIMARY_VOL_DESC].block);
1702 	if (ret < 0)
1703 		return ret;
1704 
1705 	if (vds[VDS_POS_LOGICAL_VOL_DESC].block) {
1706 		ret = udf_load_logicalvol(sb,
1707 					  vds[VDS_POS_LOGICAL_VOL_DESC].block,
1708 					  fileset);
1709 		if (ret < 0)
1710 			return ret;
1711 	}
1712 
1713 	if (vds[VDS_POS_PARTITION_DESC].block) {
1714 		/*
1715 		 * We rescan the whole descriptor sequence to find
1716 		 * partition descriptor blocks and process them.
1717 		 */
1718 		for (block = vds[VDS_POS_PARTITION_DESC].block;
1719 		     block < vds[VDS_POS_TERMINATING_DESC].block;
1720 		     block++) {
1721 			ret = udf_load_partdesc(sb, block);
1722 			if (ret < 0)
1723 				return ret;
1724 		}
1725 	}
1726 
1727 	return 0;
1728 }
1729 
1730 /*
1731  * Load Volume Descriptor Sequence described by anchor in bh
1732  *
1733  * Returns <0 on error, 0 on success
1734  */
1735 static int udf_load_sequence(struct super_block *sb, struct buffer_head *bh,
1736 			     struct kernel_lb_addr *fileset)
1737 {
1738 	struct anchorVolDescPtr *anchor;
1739 	sector_t main_s, main_e, reserve_s, reserve_e;
1740 	int ret;
1741 
1742 	anchor = (struct anchorVolDescPtr *)bh->b_data;
1743 
1744 	/* Locate the main sequence */
1745 	main_s = le32_to_cpu(anchor->mainVolDescSeqExt.extLocation);
1746 	main_e = le32_to_cpu(anchor->mainVolDescSeqExt.extLength);
1747 	main_e = main_e >> sb->s_blocksize_bits;
1748 	main_e += main_s;
1749 
1750 	/* Locate the reserve sequence */
1751 	reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
1752 	reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
1753 	reserve_e = reserve_e >> sb->s_blocksize_bits;
1754 	reserve_e += reserve_s;
1755 
1756 	/* Process the main & reserve sequences */
1757 	/* responsible for finding the PartitionDesc(s) */
1758 	ret = udf_process_sequence(sb, main_s, main_e, fileset);
1759 	if (ret != -EAGAIN)
1760 		return ret;
1761 	udf_sb_free_partitions(sb);
1762 	ret = udf_process_sequence(sb, reserve_s, reserve_e, fileset);
1763 	if (ret < 0) {
1764 		udf_sb_free_partitions(sb);
1765 		/* No sequence was OK, return -EIO */
1766 		if (ret == -EAGAIN)
1767 			ret = -EIO;
1768 	}
1769 	return ret;
1770 }
1771 
1772 /*
1773  * Check whether there is an anchor block in the given block and
1774  * load Volume Descriptor Sequence if so.
1775  *
1776  * Returns <0 on error, 0 on success, -EAGAIN is special - try next anchor
1777  * block
1778  */
1779 static int udf_check_anchor_block(struct super_block *sb, sector_t block,
1780 				  struct kernel_lb_addr *fileset)
1781 {
1782 	struct buffer_head *bh;
1783 	uint16_t ident;
1784 	int ret;
1785 
1786 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV) &&
1787 	    udf_fixed_to_variable(block) >=
1788 	    sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits)
1789 		return -EAGAIN;
1790 
1791 	bh = udf_read_tagged(sb, block, block, &ident);
1792 	if (!bh)
1793 		return -EAGAIN;
1794 	if (ident != TAG_IDENT_AVDP) {
1795 		brelse(bh);
1796 		return -EAGAIN;
1797 	}
1798 	ret = udf_load_sequence(sb, bh, fileset);
1799 	brelse(bh);
1800 	return ret;
1801 }
1802 
1803 /*
1804  * Search for an anchor volume descriptor pointer.
1805  *
1806  * Returns < 0 on error, 0 on success. -EAGAIN is special - try next set
1807  * of anchors.
1808  */
1809 static int udf_scan_anchors(struct super_block *sb, sector_t *lastblock,
1810 			    struct kernel_lb_addr *fileset)
1811 {
1812 	sector_t last[6];
1813 	int i;
1814 	struct udf_sb_info *sbi = UDF_SB(sb);
1815 	int last_count = 0;
1816 	int ret;
1817 
1818 	/* First try user provided anchor */
1819 	if (sbi->s_anchor) {
1820 		ret = udf_check_anchor_block(sb, sbi->s_anchor, fileset);
1821 		if (ret != -EAGAIN)
1822 			return ret;
1823 	}
1824 	/*
1825 	 * according to spec, anchor is in either:
1826 	 *     block 256
1827 	 *     lastblock-256
1828 	 *     lastblock
1829 	 *  however, if the disc isn't closed, it could be 512.
1830 	 */
1831 	ret = udf_check_anchor_block(sb, sbi->s_session + 256, fileset);
1832 	if (ret != -EAGAIN)
1833 		return ret;
1834 	/*
1835 	 * The trouble is which block is the last one. Drives often misreport
1836 	 * this so we try various possibilities.
1837 	 */
1838 	last[last_count++] = *lastblock;
1839 	if (*lastblock >= 1)
1840 		last[last_count++] = *lastblock - 1;
1841 	last[last_count++] = *lastblock + 1;
1842 	if (*lastblock >= 2)
1843 		last[last_count++] = *lastblock - 2;
1844 	if (*lastblock >= 150)
1845 		last[last_count++] = *lastblock - 150;
1846 	if (*lastblock >= 152)
1847 		last[last_count++] = *lastblock - 152;
1848 
1849 	for (i = 0; i < last_count; i++) {
1850 		if (last[i] >= sb->s_bdev->bd_inode->i_size >>
1851 				sb->s_blocksize_bits)
1852 			continue;
1853 		ret = udf_check_anchor_block(sb, last[i], fileset);
1854 		if (ret != -EAGAIN) {
1855 			if (!ret)
1856 				*lastblock = last[i];
1857 			return ret;
1858 		}
1859 		if (last[i] < 256)
1860 			continue;
1861 		ret = udf_check_anchor_block(sb, last[i] - 256, fileset);
1862 		if (ret != -EAGAIN) {
1863 			if (!ret)
1864 				*lastblock = last[i];
1865 			return ret;
1866 		}
1867 	}
1868 
1869 	/* Finally try block 512 in case media is open */
1870 	return udf_check_anchor_block(sb, sbi->s_session + 512, fileset);
1871 }
1872 
1873 /*
1874  * Find an anchor volume descriptor and load Volume Descriptor Sequence from
1875  * area specified by it. The function expects sbi->s_lastblock to be the last
1876  * block on the media.
1877  *
1878  * Return <0 on error, 0 if anchor found. -EAGAIN is special meaning anchor
1879  * was not found.
1880  */
1881 static int udf_find_anchor(struct super_block *sb,
1882 			   struct kernel_lb_addr *fileset)
1883 {
1884 	struct udf_sb_info *sbi = UDF_SB(sb);
1885 	sector_t lastblock = sbi->s_last_block;
1886 	int ret;
1887 
1888 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1889 	if (ret != -EAGAIN)
1890 		goto out;
1891 
1892 	/* No anchor found? Try VARCONV conversion of block numbers */
1893 	UDF_SET_FLAG(sb, UDF_FLAG_VARCONV);
1894 	lastblock = udf_variable_to_fixed(sbi->s_last_block);
1895 	/* Firstly, we try to not convert number of the last block */
1896 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1897 	if (ret != -EAGAIN)
1898 		goto out;
1899 
1900 	lastblock = sbi->s_last_block;
1901 	/* Secondly, we try with converted number of the last block */
1902 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1903 	if (ret < 0) {
1904 		/* VARCONV didn't help. Clear it. */
1905 		UDF_CLEAR_FLAG(sb, UDF_FLAG_VARCONV);
1906 	}
1907 out:
1908 	if (ret == 0)
1909 		sbi->s_last_block = lastblock;
1910 	return ret;
1911 }
1912 
1913 /*
1914  * Check Volume Structure Descriptor, find Anchor block and load Volume
1915  * Descriptor Sequence.
1916  *
1917  * Returns < 0 on error, 0 on success. -EAGAIN is special meaning anchor
1918  * block was not found.
1919  */
1920 static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
1921 			int silent, struct kernel_lb_addr *fileset)
1922 {
1923 	struct udf_sb_info *sbi = UDF_SB(sb);
1924 	loff_t nsr_off;
1925 	int ret;
1926 
1927 	if (!sb_set_blocksize(sb, uopt->blocksize)) {
1928 		if (!silent)
1929 			udf_warn(sb, "Bad block size\n");
1930 		return -EINVAL;
1931 	}
1932 	sbi->s_last_block = uopt->lastblock;
1933 	if (!uopt->novrs) {
1934 		/* Check that it is NSR02 compliant */
1935 		nsr_off = udf_check_vsd(sb);
1936 		if (!nsr_off) {
1937 			if (!silent)
1938 				udf_warn(sb, "No VRS found\n");
1939 			return 0;
1940 		}
1941 		if (nsr_off == -1)
1942 			udf_debug("Failed to read sector at offset %d. "
1943 				  "Assuming open disc. Skipping validity "
1944 				  "check\n", VSD_FIRST_SECTOR_OFFSET);
1945 		if (!sbi->s_last_block)
1946 			sbi->s_last_block = udf_get_last_block(sb);
1947 	} else {
1948 		udf_debug("Validity check skipped because of novrs option\n");
1949 	}
1950 
1951 	/* Look for anchor block and load Volume Descriptor Sequence */
1952 	sbi->s_anchor = uopt->anchor;
1953 	ret = udf_find_anchor(sb, fileset);
1954 	if (ret < 0) {
1955 		if (!silent && ret == -EAGAIN)
1956 			udf_warn(sb, "No anchor found\n");
1957 		return ret;
1958 	}
1959 	return 0;
1960 }
1961 
1962 static void udf_open_lvid(struct super_block *sb)
1963 {
1964 	struct udf_sb_info *sbi = UDF_SB(sb);
1965 	struct buffer_head *bh = sbi->s_lvid_bh;
1966 	struct logicalVolIntegrityDesc *lvid;
1967 	struct logicalVolIntegrityDescImpUse *lvidiu;
1968 
1969 	if (!bh)
1970 		return;
1971 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
1972 	lvidiu = udf_sb_lvidiu(sb);
1973 	if (!lvidiu)
1974 		return;
1975 
1976 	mutex_lock(&sbi->s_alloc_mutex);
1977 	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1978 	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1979 	udf_time_to_disk_stamp(&lvid->recordingDateAndTime,
1980 				CURRENT_TIME);
1981 	lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
1982 
1983 	lvid->descTag.descCRC = cpu_to_le16(
1984 		crc_itu_t(0, (char *)lvid + sizeof(struct tag),
1985 			le16_to_cpu(lvid->descTag.descCRCLength)));
1986 
1987 	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
1988 	mark_buffer_dirty(bh);
1989 	sbi->s_lvid_dirty = 0;
1990 	mutex_unlock(&sbi->s_alloc_mutex);
1991 	/* Make opening of filesystem visible on the media immediately */
1992 	sync_dirty_buffer(bh);
1993 }
1994 
1995 static void udf_close_lvid(struct super_block *sb)
1996 {
1997 	struct udf_sb_info *sbi = UDF_SB(sb);
1998 	struct buffer_head *bh = sbi->s_lvid_bh;
1999 	struct logicalVolIntegrityDesc *lvid;
2000 	struct logicalVolIntegrityDescImpUse *lvidiu;
2001 
2002 	if (!bh)
2003 		return;
2004 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2005 	lvidiu = udf_sb_lvidiu(sb);
2006 	if (!lvidiu)
2007 		return;
2008 
2009 	mutex_lock(&sbi->s_alloc_mutex);
2010 	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2011 	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2012 	udf_time_to_disk_stamp(&lvid->recordingDateAndTime, CURRENT_TIME);
2013 	if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
2014 		lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
2015 	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
2016 		lvidiu->minUDFReadRev = cpu_to_le16(sbi->s_udfrev);
2017 	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFWriteRev))
2018 		lvidiu->minUDFWriteRev = cpu_to_le16(sbi->s_udfrev);
2019 	lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);
2020 
2021 	lvid->descTag.descCRC = cpu_to_le16(
2022 			crc_itu_t(0, (char *)lvid + sizeof(struct tag),
2023 				le16_to_cpu(lvid->descTag.descCRCLength)));
2024 
2025 	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
2026 	/*
2027 	 * We set buffer uptodate unconditionally here to avoid spurious
2028 	 * warnings from mark_buffer_dirty() when previous EIO has marked
2029 	 * the buffer as !uptodate
2030 	 */
2031 	set_buffer_uptodate(bh);
2032 	mark_buffer_dirty(bh);
2033 	sbi->s_lvid_dirty = 0;
2034 	mutex_unlock(&sbi->s_alloc_mutex);
2035 	/* Make closing of filesystem visible on the media immediately */
2036 	sync_dirty_buffer(bh);
2037 }
2038 
2039 u64 lvid_get_unique_id(struct super_block *sb)
2040 {
2041 	struct buffer_head *bh;
2042 	struct udf_sb_info *sbi = UDF_SB(sb);
2043 	struct logicalVolIntegrityDesc *lvid;
2044 	struct logicalVolHeaderDesc *lvhd;
2045 	u64 uniqueID;
2046 	u64 ret;
2047 
2048 	bh = sbi->s_lvid_bh;
2049 	if (!bh)
2050 		return 0;
2051 
2052 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2053 	lvhd = (struct logicalVolHeaderDesc *)lvid->logicalVolContentsUse;
2054 
2055 	mutex_lock(&sbi->s_alloc_mutex);
2056 	ret = uniqueID = le64_to_cpu(lvhd->uniqueID);
2057 	if (!(++uniqueID & 0xFFFFFFFF))
2058 		uniqueID += 16;
2059 	lvhd->uniqueID = cpu_to_le64(uniqueID);
2060 	mutex_unlock(&sbi->s_alloc_mutex);
2061 	mark_buffer_dirty(bh);
2062 
2063 	return ret;
2064 }
2065 
2066 static int udf_fill_super(struct super_block *sb, void *options, int silent)
2067 {
2068 	int ret = -EINVAL;
2069 	struct inode *inode = NULL;
2070 	struct udf_options uopt;
2071 	struct kernel_lb_addr rootdir, fileset;
2072 	struct udf_sb_info *sbi;
2073 	bool lvid_open = false;
2074 
2075 	uopt.flags = (1 << UDF_FLAG_USE_AD_IN_ICB) | (1 << UDF_FLAG_STRICT);
2076 	uopt.uid = INVALID_UID;
2077 	uopt.gid = INVALID_GID;
2078 	uopt.umask = 0;
2079 	uopt.fmode = UDF_INVALID_MODE;
2080 	uopt.dmode = UDF_INVALID_MODE;
2081 
2082 	sbi = kzalloc(sizeof(struct udf_sb_info), GFP_KERNEL);
2083 	if (!sbi)
2084 		return -ENOMEM;
2085 
2086 	sb->s_fs_info = sbi;
2087 
2088 	mutex_init(&sbi->s_alloc_mutex);
2089 
2090 	if (!udf_parse_options((char *)options, &uopt, false))
2091 		goto parse_options_failure;
2092 
2093 	if (uopt.flags & (1 << UDF_FLAG_UTF8) &&
2094 	    uopt.flags & (1 << UDF_FLAG_NLS_MAP)) {
2095 		udf_err(sb, "utf8 cannot be combined with iocharset\n");
2096 		goto parse_options_failure;
2097 	}
2098 #ifdef CONFIG_UDF_NLS
2099 	if ((uopt.flags & (1 << UDF_FLAG_NLS_MAP)) && !uopt.nls_map) {
2100 		uopt.nls_map = load_nls_default();
2101 		if (!uopt.nls_map)
2102 			uopt.flags &= ~(1 << UDF_FLAG_NLS_MAP);
2103 		else
2104 			udf_debug("Using default NLS map\n");
2105 	}
2106 #endif
2107 	if (!(uopt.flags & (1 << UDF_FLAG_NLS_MAP)))
2108 		uopt.flags |= (1 << UDF_FLAG_UTF8);
2109 
2110 	fileset.logicalBlockNum = 0xFFFFFFFF;
2111 	fileset.partitionReferenceNum = 0xFFFF;
2112 
2113 	sbi->s_flags = uopt.flags;
2114 	sbi->s_uid = uopt.uid;
2115 	sbi->s_gid = uopt.gid;
2116 	sbi->s_umask = uopt.umask;
2117 	sbi->s_fmode = uopt.fmode;
2118 	sbi->s_dmode = uopt.dmode;
2119 	sbi->s_nls_map = uopt.nls_map;
2120 	rwlock_init(&sbi->s_cred_lock);
2121 
2122 	if (uopt.session == 0xFFFFFFFF)
2123 		sbi->s_session = udf_get_last_session(sb);
2124 	else
2125 		sbi->s_session = uopt.session;
2126 
2127 	udf_debug("Multi-session=%d\n", sbi->s_session);
2128 
2129 	/* Fill in the rest of the superblock */
2130 	sb->s_op = &udf_sb_ops;
2131 	sb->s_export_op = &udf_export_ops;
2132 
2133 	sb->s_magic = UDF_SUPER_MAGIC;
2134 	sb->s_time_gran = 1000;
2135 
2136 	if (uopt.flags & (1 << UDF_FLAG_BLOCKSIZE_SET)) {
2137 		ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2138 	} else {
2139 		uopt.blocksize = bdev_logical_block_size(sb->s_bdev);
2140 		ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2141 		if (ret == -EAGAIN && uopt.blocksize != UDF_DEFAULT_BLOCKSIZE) {
2142 			if (!silent)
2143 				pr_notice("Rescanning with blocksize %d\n",
2144 					  UDF_DEFAULT_BLOCKSIZE);
2145 			brelse(sbi->s_lvid_bh);
2146 			sbi->s_lvid_bh = NULL;
2147 			uopt.blocksize = UDF_DEFAULT_BLOCKSIZE;
2148 			ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2149 		}
2150 	}
2151 	if (ret < 0) {
2152 		if (ret == -EAGAIN) {
2153 			udf_warn(sb, "No partition found (1)\n");
2154 			ret = -EINVAL;
2155 		}
2156 		goto error_out;
2157 	}
2158 
2159 	udf_debug("Lastblock=%d\n", sbi->s_last_block);
2160 
2161 	if (sbi->s_lvid_bh) {
2162 		struct logicalVolIntegrityDescImpUse *lvidiu =
2163 							udf_sb_lvidiu(sb);
2164 		uint16_t minUDFReadRev;
2165 		uint16_t minUDFWriteRev;
2166 
2167 		if (!lvidiu) {
2168 			ret = -EINVAL;
2169 			goto error_out;
2170 		}
2171 		minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev);
2172 		minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev);
2173 		if (minUDFReadRev > UDF_MAX_READ_VERSION) {
2174 			udf_err(sb, "minUDFReadRev=%x (max is %x)\n",
2175 				minUDFReadRev,
2176 				UDF_MAX_READ_VERSION);
2177 			ret = -EINVAL;
2178 			goto error_out;
2179 		} else if (minUDFWriteRev > UDF_MAX_WRITE_VERSION &&
2180 			   !(sb->s_flags & MS_RDONLY)) {
2181 			ret = -EACCES;
2182 			goto error_out;
2183 		}
2184 
2185 		sbi->s_udfrev = minUDFWriteRev;
2186 
2187 		if (minUDFReadRev >= UDF_VERS_USE_EXTENDED_FE)
2188 			UDF_SET_FLAG(sb, UDF_FLAG_USE_EXTENDED_FE);
2189 		if (minUDFReadRev >= UDF_VERS_USE_STREAMS)
2190 			UDF_SET_FLAG(sb, UDF_FLAG_USE_STREAMS);
2191 	}
2192 
2193 	if (!sbi->s_partitions) {
2194 		udf_warn(sb, "No partition found (2)\n");
2195 		ret = -EINVAL;
2196 		goto error_out;
2197 	}
2198 
2199 	if (sbi->s_partmaps[sbi->s_partition].s_partition_flags &
2200 			UDF_PART_FLAG_READ_ONLY &&
2201 	    !(sb->s_flags & MS_RDONLY)) {
2202 		ret = -EACCES;
2203 		goto error_out;
2204 	}
2205 
2206 	if (udf_find_fileset(sb, &fileset, &rootdir)) {
2207 		udf_warn(sb, "No fileset found\n");
2208 		ret = -EINVAL;
2209 		goto error_out;
2210 	}
2211 
2212 	if (!silent) {
2213 		struct timestamp ts;
2214 		udf_time_to_disk_stamp(&ts, sbi->s_record_time);
2215 		udf_info("Mounting volume '%s', timestamp %04u/%02u/%02u %02u:%02u (%x)\n",
2216 			 sbi->s_volume_ident,
2217 			 le16_to_cpu(ts.year), ts.month, ts.day,
2218 			 ts.hour, ts.minute, le16_to_cpu(ts.typeAndTimezone));
2219 	}
2220 	if (!(sb->s_flags & MS_RDONLY)) {
2221 		udf_open_lvid(sb);
2222 		lvid_open = true;
2223 	}
2224 
2225 	/* Assign the root inode */
2226 	/* assign inodes by physical block number */
2227 	/* perhaps it's not extensible enough, but for now ... */
2228 	inode = udf_iget(sb, &rootdir);
2229 	if (IS_ERR(inode)) {
2230 		udf_err(sb, "Error in udf_iget, block=%d, partition=%d\n",
2231 		       rootdir.logicalBlockNum, rootdir.partitionReferenceNum);
2232 		ret = PTR_ERR(inode);
2233 		goto error_out;
2234 	}
2235 
2236 	/* Allocate a dentry for the root inode */
2237 	sb->s_root = d_make_root(inode);
2238 	if (!sb->s_root) {
2239 		udf_err(sb, "Couldn't allocate root dentry\n");
2240 		ret = -ENOMEM;
2241 		goto error_out;
2242 	}
2243 	sb->s_maxbytes = MAX_LFS_FILESIZE;
2244 	sb->s_max_links = UDF_MAX_LINKS;
2245 	return 0;
2246 
2247 error_out:
2248 	iput(sbi->s_vat_inode);
2249 parse_options_failure:
2250 #ifdef CONFIG_UDF_NLS
2251 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
2252 		unload_nls(sbi->s_nls_map);
2253 #endif
2254 	if (lvid_open)
2255 		udf_close_lvid(sb);
2256 	brelse(sbi->s_lvid_bh);
2257 	udf_sb_free_partitions(sb);
2258 	kfree(sbi);
2259 	sb->s_fs_info = NULL;
2260 
2261 	return ret;
2262 }
2263 
2264 void _udf_err(struct super_block *sb, const char *function,
2265 	      const char *fmt, ...)
2266 {
2267 	struct va_format vaf;
2268 	va_list args;
2269 
2270 	va_start(args, fmt);
2271 
2272 	vaf.fmt = fmt;
2273 	vaf.va = &args;
2274 
2275 	pr_err("error (device %s): %s: %pV", sb->s_id, function, &vaf);
2276 
2277 	va_end(args);
2278 }
2279 
2280 void _udf_warn(struct super_block *sb, const char *function,
2281 	       const char *fmt, ...)
2282 {
2283 	struct va_format vaf;
2284 	va_list args;
2285 
2286 	va_start(args, fmt);
2287 
2288 	vaf.fmt = fmt;
2289 	vaf.va = &args;
2290 
2291 	pr_warn("warning (device %s): %s: %pV", sb->s_id, function, &vaf);
2292 
2293 	va_end(args);
2294 }
2295 
2296 static void udf_put_super(struct super_block *sb)
2297 {
2298 	struct udf_sb_info *sbi;
2299 
2300 	sbi = UDF_SB(sb);
2301 
2302 	iput(sbi->s_vat_inode);
2303 #ifdef CONFIG_UDF_NLS
2304 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
2305 		unload_nls(sbi->s_nls_map);
2306 #endif
2307 	if (!(sb->s_flags & MS_RDONLY))
2308 		udf_close_lvid(sb);
2309 	brelse(sbi->s_lvid_bh);
2310 	udf_sb_free_partitions(sb);
2311 	mutex_destroy(&sbi->s_alloc_mutex);
2312 	kfree(sb->s_fs_info);
2313 	sb->s_fs_info = NULL;
2314 }
2315 
2316 static int udf_sync_fs(struct super_block *sb, int wait)
2317 {
2318 	struct udf_sb_info *sbi = UDF_SB(sb);
2319 
2320 	mutex_lock(&sbi->s_alloc_mutex);
2321 	if (sbi->s_lvid_dirty) {
2322 		/*
2323 		 * Blockdevice will be synced later so we don't have to submit
2324 		 * the buffer for IO
2325 		 */
2326 		mark_buffer_dirty(sbi->s_lvid_bh);
2327 		sbi->s_lvid_dirty = 0;
2328 	}
2329 	mutex_unlock(&sbi->s_alloc_mutex);
2330 
2331 	return 0;
2332 }
2333 
2334 static int udf_statfs(struct dentry *dentry, struct kstatfs *buf)
2335 {
2336 	struct super_block *sb = dentry->d_sb;
2337 	struct udf_sb_info *sbi = UDF_SB(sb);
2338 	struct logicalVolIntegrityDescImpUse *lvidiu;
2339 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
2340 
2341 	lvidiu = udf_sb_lvidiu(sb);
2342 	buf->f_type = UDF_SUPER_MAGIC;
2343 	buf->f_bsize = sb->s_blocksize;
2344 	buf->f_blocks = sbi->s_partmaps[sbi->s_partition].s_partition_len;
2345 	buf->f_bfree = udf_count_free(sb);
2346 	buf->f_bavail = buf->f_bfree;
2347 	buf->f_files = (lvidiu != NULL ? (le32_to_cpu(lvidiu->numFiles) +
2348 					  le32_to_cpu(lvidiu->numDirs)) : 0)
2349 			+ buf->f_bfree;
2350 	buf->f_ffree = buf->f_bfree;
2351 	buf->f_namelen = UDF_NAME_LEN - 2;
2352 	buf->f_fsid.val[0] = (u32)id;
2353 	buf->f_fsid.val[1] = (u32)(id >> 32);
2354 
2355 	return 0;
2356 }
2357 
2358 static unsigned int udf_count_free_bitmap(struct super_block *sb,
2359 					  struct udf_bitmap *bitmap)
2360 {
2361 	struct buffer_head *bh = NULL;
2362 	unsigned int accum = 0;
2363 	int index;
2364 	int block = 0, newblock;
2365 	struct kernel_lb_addr loc;
2366 	uint32_t bytes;
2367 	uint8_t *ptr;
2368 	uint16_t ident;
2369 	struct spaceBitmapDesc *bm;
2370 
2371 	loc.logicalBlockNum = bitmap->s_extPosition;
2372 	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
2373 	bh = udf_read_ptagged(sb, &loc, 0, &ident);
2374 
2375 	if (!bh) {
2376 		udf_err(sb, "udf_count_free failed\n");
2377 		goto out;
2378 	} else if (ident != TAG_IDENT_SBD) {
2379 		brelse(bh);
2380 		udf_err(sb, "udf_count_free failed\n");
2381 		goto out;
2382 	}
2383 
2384 	bm = (struct spaceBitmapDesc *)bh->b_data;
2385 	bytes = le32_to_cpu(bm->numOfBytes);
2386 	index = sizeof(struct spaceBitmapDesc); /* offset in first block only */
2387 	ptr = (uint8_t *)bh->b_data;
2388 
2389 	while (bytes > 0) {
2390 		u32 cur_bytes = min_t(u32, bytes, sb->s_blocksize - index);
2391 		accum += bitmap_weight((const unsigned long *)(ptr + index),
2392 					cur_bytes * 8);
2393 		bytes -= cur_bytes;
2394 		if (bytes) {
2395 			brelse(bh);
2396 			newblock = udf_get_lb_pblock(sb, &loc, ++block);
2397 			bh = udf_tread(sb, newblock);
2398 			if (!bh) {
2399 				udf_debug("read failed\n");
2400 				goto out;
2401 			}
2402 			index = 0;
2403 			ptr = (uint8_t *)bh->b_data;
2404 		}
2405 	}
2406 	brelse(bh);
2407 out:
2408 	return accum;
2409 }
2410 
2411 static unsigned int udf_count_free_table(struct super_block *sb,
2412 					 struct inode *table)
2413 {
2414 	unsigned int accum = 0;
2415 	uint32_t elen;
2416 	struct kernel_lb_addr eloc;
2417 	int8_t etype;
2418 	struct extent_position epos;
2419 
2420 	mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
2421 	epos.block = UDF_I(table)->i_location;
2422 	epos.offset = sizeof(struct unallocSpaceEntry);
2423 	epos.bh = NULL;
2424 
2425 	while ((etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1)
2426 		accum += (elen >> table->i_sb->s_blocksize_bits);
2427 
2428 	brelse(epos.bh);
2429 	mutex_unlock(&UDF_SB(sb)->s_alloc_mutex);
2430 
2431 	return accum;
2432 }
2433 
2434 static unsigned int udf_count_free(struct super_block *sb)
2435 {
2436 	unsigned int accum = 0;
2437 	struct udf_sb_info *sbi;
2438 	struct udf_part_map *map;
2439 
2440 	sbi = UDF_SB(sb);
2441 	if (sbi->s_lvid_bh) {
2442 		struct logicalVolIntegrityDesc *lvid =
2443 			(struct logicalVolIntegrityDesc *)
2444 			sbi->s_lvid_bh->b_data;
2445 		if (le32_to_cpu(lvid->numOfPartitions) > sbi->s_partition) {
2446 			accum = le32_to_cpu(
2447 					lvid->freeSpaceTable[sbi->s_partition]);
2448 			if (accum == 0xFFFFFFFF)
2449 				accum = 0;
2450 		}
2451 	}
2452 
2453 	if (accum)
2454 		return accum;
2455 
2456 	map = &sbi->s_partmaps[sbi->s_partition];
2457 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
2458 		accum += udf_count_free_bitmap(sb,
2459 					       map->s_uspace.s_bitmap);
2460 	}
2461 	if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) {
2462 		accum += udf_count_free_bitmap(sb,
2463 					       map->s_fspace.s_bitmap);
2464 	}
2465 	if (accum)
2466 		return accum;
2467 
2468 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
2469 		accum += udf_count_free_table(sb,
2470 					      map->s_uspace.s_table);
2471 	}
2472 	if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) {
2473 		accum += udf_count_free_table(sb,
2474 					      map->s_fspace.s_table);
2475 	}
2476 
2477 	return accum;
2478 }
2479