xref: /openbmc/linux/fs/udf/super.c (revision ac3cb6de)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * super.c
4  *
5  * PURPOSE
6  *  Super block routines for the OSTA-UDF(tm) filesystem.
7  *
8  * DESCRIPTION
9  *  OSTA-UDF(tm) = Optical Storage Technology Association
10  *  Universal Disk Format.
11  *
12  *  This code is based on version 2.00 of the UDF specification,
13  *  and revision 3 of the ECMA 167 standard [equivalent to ISO 13346].
14  *    http://www.osta.org/
15  *    https://www.ecma.ch/
16  *    https://www.iso.org/
17  *
18  * COPYRIGHT
19  *  (C) 1998 Dave Boynton
20  *  (C) 1998-2004 Ben Fennema
21  *  (C) 2000 Stelias Computing Inc
22  *
23  * HISTORY
24  *
25  *  09/24/98 dgb  changed to allow compiling outside of kernel, and
26  *                added some debugging.
27  *  10/01/98 dgb  updated to allow (some) possibility of compiling w/2.0.34
28  *  10/16/98      attempting some multi-session support
29  *  10/17/98      added freespace count for "df"
30  *  11/11/98 gr   added novrs option
31  *  11/26/98 dgb  added fileset,anchor mount options
32  *  12/06/98 blf  really hosed things royally. vat/sparing support. sequenced
33  *                vol descs. rewrote option handling based on isofs
34  *  12/20/98      find the free space bitmap (if it exists)
35  */
36 
37 #include "udfdecl.h"
38 
39 #include <linux/blkdev.h>
40 #include <linux/slab.h>
41 #include <linux/kernel.h>
42 #include <linux/module.h>
43 #include <linux/parser.h>
44 #include <linux/stat.h>
45 #include <linux/cdrom.h>
46 #include <linux/nls.h>
47 #include <linux/vfs.h>
48 #include <linux/vmalloc.h>
49 #include <linux/errno.h>
50 #include <linux/mount.h>
51 #include <linux/seq_file.h>
52 #include <linux/bitmap.h>
53 #include <linux/crc-itu-t.h>
54 #include <linux/log2.h>
55 #include <asm/byteorder.h>
56 #include <linux/iversion.h>
57 
58 #include "udf_sb.h"
59 #include "udf_i.h"
60 
61 #include <linux/init.h>
62 #include <linux/uaccess.h>
63 
64 enum {
65 	VDS_POS_PRIMARY_VOL_DESC,
66 	VDS_POS_UNALLOC_SPACE_DESC,
67 	VDS_POS_LOGICAL_VOL_DESC,
68 	VDS_POS_IMP_USE_VOL_DESC,
69 	VDS_POS_LENGTH
70 };
71 
72 #define VSD_FIRST_SECTOR_OFFSET		32768
73 #define VSD_MAX_SECTOR_OFFSET		0x800000
74 
75 /*
76  * Maximum number of Terminating Descriptor / Logical Volume Integrity
77  * Descriptor redirections. The chosen numbers are arbitrary - just that we
78  * hopefully don't limit any real use of rewritten inode on write-once media
79  * but avoid looping for too long on corrupted media.
80  */
81 #define UDF_MAX_TD_NESTING 64
82 #define UDF_MAX_LVID_NESTING 1000
83 
84 enum { UDF_MAX_LINKS = 0xffff };
85 /*
86  * We limit filesize to 4TB. This is arbitrary as the on-disk format supports
87  * more but because the file space is described by a linked list of extents,
88  * each of which can have at most 1GB, the creation and handling of extents
89  * gets unusably slow beyond certain point...
90  */
91 #define UDF_MAX_FILESIZE (1ULL << 42)
92 
93 /* These are the "meat" - everything else is stuffing */
94 static int udf_fill_super(struct super_block *, void *, int);
95 static void udf_put_super(struct super_block *);
96 static int udf_sync_fs(struct super_block *, int);
97 static int udf_remount_fs(struct super_block *, int *, char *);
98 static void udf_load_logicalvolint(struct super_block *, struct kernel_extent_ad);
99 static void udf_open_lvid(struct super_block *);
100 static void udf_close_lvid(struct super_block *);
101 static unsigned int udf_count_free(struct super_block *);
102 static int udf_statfs(struct dentry *, struct kstatfs *);
103 static int udf_show_options(struct seq_file *, struct dentry *);
104 
105 struct logicalVolIntegrityDescImpUse *udf_sb_lvidiu(struct super_block *sb)
106 {
107 	struct logicalVolIntegrityDesc *lvid;
108 	unsigned int partnum;
109 	unsigned int offset;
110 
111 	if (!UDF_SB(sb)->s_lvid_bh)
112 		return NULL;
113 	lvid = (struct logicalVolIntegrityDesc *)UDF_SB(sb)->s_lvid_bh->b_data;
114 	partnum = le32_to_cpu(lvid->numOfPartitions);
115 	/* The offset is to skip freeSpaceTable and sizeTable arrays */
116 	offset = partnum * 2 * sizeof(uint32_t);
117 	return (struct logicalVolIntegrityDescImpUse *)
118 					(((uint8_t *)(lvid + 1)) + 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 = alloc_inode_sb(sb, 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_lenStreams = 0;
149 	ei->i_next_alloc_block = 0;
150 	ei->i_next_alloc_goal = 0;
151 	ei->i_strat4096 = 0;
152 	ei->i_streamdir = 0;
153 	ei->i_hidden = 0;
154 	init_rwsem(&ei->i_data_sem);
155 	ei->cached_extent.lstart = -1;
156 	spin_lock_init(&ei->i_extent_cache_lock);
157 	inode_set_iversion(&ei->vfs_inode, 1);
158 
159 	return &ei->vfs_inode;
160 }
161 
162 static void udf_free_in_core_inode(struct inode *inode)
163 {
164 	kmem_cache_free(udf_inode_cachep, UDF_I(inode));
165 }
166 
167 static void init_once(void *foo)
168 {
169 	struct udf_inode_info *ei = foo;
170 
171 	ei->i_data = NULL;
172 	inode_init_once(&ei->vfs_inode);
173 }
174 
175 static int __init 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 						 SLAB_ACCOUNT),
182 					     init_once);
183 	if (!udf_inode_cachep)
184 		return -ENOMEM;
185 	return 0;
186 }
187 
188 static void destroy_inodecache(void)
189 {
190 	/*
191 	 * Make sure all delayed rcu free inodes are flushed before we
192 	 * destroy cache.
193 	 */
194 	rcu_barrier();
195 	kmem_cache_destroy(udf_inode_cachep);
196 }
197 
198 /* Superblock operations */
199 static const struct super_operations udf_sb_ops = {
200 	.alloc_inode	= udf_alloc_inode,
201 	.free_inode	= udf_free_in_core_inode,
202 	.write_inode	= udf_write_inode,
203 	.evict_inode	= udf_evict_inode,
204 	.put_super	= udf_put_super,
205 	.sync_fs	= udf_sync_fs,
206 	.statfs		= udf_statfs,
207 	.remount_fs	= udf_remount_fs,
208 	.show_options	= udf_show_options,
209 };
210 
211 struct udf_options {
212 	unsigned char novrs;
213 	unsigned int blocksize;
214 	unsigned int session;
215 	unsigned int lastblock;
216 	unsigned int anchor;
217 	unsigned int flags;
218 	umode_t umask;
219 	kgid_t gid;
220 	kuid_t uid;
221 	umode_t fmode;
222 	umode_t dmode;
223 	struct nls_table *nls_map;
224 };
225 
226 static int __init init_udf_fs(void)
227 {
228 	int err;
229 
230 	err = init_inodecache();
231 	if (err)
232 		goto out1;
233 	err = register_filesystem(&udf_fstype);
234 	if (err)
235 		goto out;
236 
237 	return 0;
238 
239 out:
240 	destroy_inodecache();
241 
242 out1:
243 	return err;
244 }
245 
246 static void __exit exit_udf_fs(void)
247 {
248 	unregister_filesystem(&udf_fstype);
249 	destroy_inodecache();
250 }
251 
252 static int udf_sb_alloc_partition_maps(struct super_block *sb, u32 count)
253 {
254 	struct udf_sb_info *sbi = UDF_SB(sb);
255 
256 	sbi->s_partmaps = kcalloc(count, sizeof(*sbi->s_partmaps), GFP_KERNEL);
257 	if (!sbi->s_partmaps) {
258 		sbi->s_partitions = 0;
259 		return -ENOMEM;
260 	}
261 
262 	sbi->s_partitions = count;
263 	return 0;
264 }
265 
266 static void udf_sb_free_bitmap(struct udf_bitmap *bitmap)
267 {
268 	int i;
269 	int nr_groups = bitmap->s_nr_groups;
270 
271 	for (i = 0; i < nr_groups; i++)
272 		brelse(bitmap->s_block_bitmap[i]);
273 
274 	kvfree(bitmap);
275 }
276 
277 static void udf_free_partition(struct udf_part_map *map)
278 {
279 	int i;
280 	struct udf_meta_data *mdata;
281 
282 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
283 		iput(map->s_uspace.s_table);
284 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
285 		udf_sb_free_bitmap(map->s_uspace.s_bitmap);
286 	if (map->s_partition_type == UDF_SPARABLE_MAP15)
287 		for (i = 0; i < 4; i++)
288 			brelse(map->s_type_specific.s_sparing.s_spar_map[i]);
289 	else if (map->s_partition_type == UDF_METADATA_MAP25) {
290 		mdata = &map->s_type_specific.s_metadata;
291 		iput(mdata->s_metadata_fe);
292 		mdata->s_metadata_fe = NULL;
293 
294 		iput(mdata->s_mirror_fe);
295 		mdata->s_mirror_fe = NULL;
296 
297 		iput(mdata->s_bitmap_fe);
298 		mdata->s_bitmap_fe = NULL;
299 	}
300 }
301 
302 static void udf_sb_free_partitions(struct super_block *sb)
303 {
304 	struct udf_sb_info *sbi = UDF_SB(sb);
305 	int i;
306 
307 	if (!sbi->s_partmaps)
308 		return;
309 	for (i = 0; i < sbi->s_partitions; i++)
310 		udf_free_partition(&sbi->s_partmaps[i]);
311 	kfree(sbi->s_partmaps);
312 	sbi->s_partmaps = NULL;
313 }
314 
315 static int udf_show_options(struct seq_file *seq, struct dentry *root)
316 {
317 	struct super_block *sb = root->d_sb;
318 	struct udf_sb_info *sbi = UDF_SB(sb);
319 
320 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT))
321 		seq_puts(seq, ",nostrict");
322 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_BLOCKSIZE_SET))
323 		seq_printf(seq, ",bs=%lu", sb->s_blocksize);
324 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
325 		seq_puts(seq, ",unhide");
326 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
327 		seq_puts(seq, ",undelete");
328 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_USE_AD_IN_ICB))
329 		seq_puts(seq, ",noadinicb");
330 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_USE_SHORT_AD))
331 		seq_puts(seq, ",shortad");
332 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_FORGET))
333 		seq_puts(seq, ",uid=forget");
334 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_FORGET))
335 		seq_puts(seq, ",gid=forget");
336 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET))
337 		seq_printf(seq, ",uid=%u", from_kuid(&init_user_ns, sbi->s_uid));
338 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET))
339 		seq_printf(seq, ",gid=%u", from_kgid(&init_user_ns, sbi->s_gid));
340 	if (sbi->s_umask != 0)
341 		seq_printf(seq, ",umask=%ho", sbi->s_umask);
342 	if (sbi->s_fmode != UDF_INVALID_MODE)
343 		seq_printf(seq, ",mode=%ho", sbi->s_fmode);
344 	if (sbi->s_dmode != UDF_INVALID_MODE)
345 		seq_printf(seq, ",dmode=%ho", sbi->s_dmode);
346 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_SESSION_SET))
347 		seq_printf(seq, ",session=%d", sbi->s_session);
348 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_LASTBLOCK_SET))
349 		seq_printf(seq, ",lastblock=%u", sbi->s_last_block);
350 	if (sbi->s_anchor != 0)
351 		seq_printf(seq, ",anchor=%u", sbi->s_anchor);
352 	if (sbi->s_nls_map)
353 		seq_printf(seq, ",iocharset=%s", sbi->s_nls_map->charset);
354 	else
355 		seq_puts(seq, ",iocharset=utf8");
356 
357 	return 0;
358 }
359 
360 /*
361  * udf_parse_options
362  *
363  * PURPOSE
364  *	Parse mount options.
365  *
366  * DESCRIPTION
367  *	The following mount options are supported:
368  *
369  *	gid=		Set the default group.
370  *	umask=		Set the default umask.
371  *	mode=		Set the default file permissions.
372  *	dmode=		Set the default directory permissions.
373  *	uid=		Set the default user.
374  *	bs=		Set the block size.
375  *	unhide		Show otherwise hidden files.
376  *	undelete	Show deleted files in lists.
377  *	adinicb		Embed data in the inode (default)
378  *	noadinicb	Don't embed data in the inode
379  *	shortad		Use short ad's
380  *	longad		Use long ad's (default)
381  *	nostrict	Unset strict conformance
382  *	iocharset=	Set the NLS character set
383  *
384  *	The remaining are for debugging and disaster recovery:
385  *
386  *	novrs		Skip volume sequence recognition
387  *
388  *	The following expect a offset from 0.
389  *
390  *	session=	Set the CDROM session (default= last session)
391  *	anchor=		Override standard anchor location. (default= 256)
392  *	volume=		Override the VolumeDesc location. (unused)
393  *	partition=	Override the PartitionDesc location. (unused)
394  *	lastblock=	Set the last block of the filesystem/
395  *
396  *	The following expect a offset from the partition root.
397  *
398  *	fileset=	Override the fileset block location. (unused)
399  *	rootdir=	Override the root directory location. (unused)
400  *		WARNING: overriding the rootdir to a non-directory may
401  *		yield highly unpredictable results.
402  *
403  * PRE-CONDITIONS
404  *	options		Pointer to mount options string.
405  *	uopts		Pointer to mount options variable.
406  *
407  * POST-CONDITIONS
408  *	<return>	1	Mount options parsed okay.
409  *	<return>	0	Error parsing mount options.
410  *
411  * HISTORY
412  *	July 1, 1997 - Andrew E. Mileski
413  *	Written, tested, and released.
414  */
415 
416 enum {
417 	Opt_novrs, Opt_nostrict, Opt_bs, Opt_unhide, Opt_undelete,
418 	Opt_noadinicb, Opt_adinicb, Opt_shortad, Opt_longad,
419 	Opt_gid, Opt_uid, Opt_umask, Opt_session, Opt_lastblock,
420 	Opt_anchor, Opt_volume, Opt_partition, Opt_fileset,
421 	Opt_rootdir, Opt_utf8, Opt_iocharset,
422 	Opt_err, Opt_uforget, Opt_uignore, Opt_gforget, Opt_gignore,
423 	Opt_fmode, Opt_dmode
424 };
425 
426 static const match_table_t tokens = {
427 	{Opt_novrs,	"novrs"},
428 	{Opt_nostrict,	"nostrict"},
429 	{Opt_bs,	"bs=%u"},
430 	{Opt_unhide,	"unhide"},
431 	{Opt_undelete,	"undelete"},
432 	{Opt_noadinicb,	"noadinicb"},
433 	{Opt_adinicb,	"adinicb"},
434 	{Opt_shortad,	"shortad"},
435 	{Opt_longad,	"longad"},
436 	{Opt_uforget,	"uid=forget"},
437 	{Opt_uignore,	"uid=ignore"},
438 	{Opt_gforget,	"gid=forget"},
439 	{Opt_gignore,	"gid=ignore"},
440 	{Opt_gid,	"gid=%u"},
441 	{Opt_uid,	"uid=%u"},
442 	{Opt_umask,	"umask=%o"},
443 	{Opt_session,	"session=%u"},
444 	{Opt_lastblock,	"lastblock=%u"},
445 	{Opt_anchor,	"anchor=%u"},
446 	{Opt_volume,	"volume=%u"},
447 	{Opt_partition,	"partition=%u"},
448 	{Opt_fileset,	"fileset=%u"},
449 	{Opt_rootdir,	"rootdir=%u"},
450 	{Opt_utf8,	"utf8"},
451 	{Opt_iocharset,	"iocharset=%s"},
452 	{Opt_fmode,     "mode=%o"},
453 	{Opt_dmode,     "dmode=%o"},
454 	{Opt_err,	NULL}
455 };
456 
457 static int udf_parse_options(char *options, struct udf_options *uopt,
458 			     bool remount)
459 {
460 	char *p;
461 	int option;
462 	unsigned int uv;
463 
464 	uopt->novrs = 0;
465 	uopt->session = 0xFFFFFFFF;
466 	uopt->lastblock = 0;
467 	uopt->anchor = 0;
468 
469 	if (!options)
470 		return 1;
471 
472 	while ((p = strsep(&options, ",")) != NULL) {
473 		substring_t args[MAX_OPT_ARGS];
474 		int token;
475 		unsigned n;
476 		if (!*p)
477 			continue;
478 
479 		token = match_token(p, tokens, args);
480 		switch (token) {
481 		case Opt_novrs:
482 			uopt->novrs = 1;
483 			break;
484 		case Opt_bs:
485 			if (match_int(&args[0], &option))
486 				return 0;
487 			n = option;
488 			if (n != 512 && n != 1024 && n != 2048 && n != 4096)
489 				return 0;
490 			uopt->blocksize = n;
491 			uopt->flags |= (1 << UDF_FLAG_BLOCKSIZE_SET);
492 			break;
493 		case Opt_unhide:
494 			uopt->flags |= (1 << UDF_FLAG_UNHIDE);
495 			break;
496 		case Opt_undelete:
497 			uopt->flags |= (1 << UDF_FLAG_UNDELETE);
498 			break;
499 		case Opt_noadinicb:
500 			uopt->flags &= ~(1 << UDF_FLAG_USE_AD_IN_ICB);
501 			break;
502 		case Opt_adinicb:
503 			uopt->flags |= (1 << UDF_FLAG_USE_AD_IN_ICB);
504 			break;
505 		case Opt_shortad:
506 			uopt->flags |= (1 << UDF_FLAG_USE_SHORT_AD);
507 			break;
508 		case Opt_longad:
509 			uopt->flags &= ~(1 << UDF_FLAG_USE_SHORT_AD);
510 			break;
511 		case Opt_gid:
512 			if (match_uint(args, &uv))
513 				return 0;
514 			uopt->gid = make_kgid(current_user_ns(), uv);
515 			if (!gid_valid(uopt->gid))
516 				return 0;
517 			uopt->flags |= (1 << UDF_FLAG_GID_SET);
518 			break;
519 		case Opt_uid:
520 			if (match_uint(args, &uv))
521 				return 0;
522 			uopt->uid = make_kuid(current_user_ns(), uv);
523 			if (!uid_valid(uopt->uid))
524 				return 0;
525 			uopt->flags |= (1 << UDF_FLAG_UID_SET);
526 			break;
527 		case Opt_umask:
528 			if (match_octal(args, &option))
529 				return 0;
530 			uopt->umask = option;
531 			break;
532 		case Opt_nostrict:
533 			uopt->flags &= ~(1 << UDF_FLAG_STRICT);
534 			break;
535 		case Opt_session:
536 			if (match_int(args, &option))
537 				return 0;
538 			uopt->session = option;
539 			if (!remount)
540 				uopt->flags |= (1 << UDF_FLAG_SESSION_SET);
541 			break;
542 		case Opt_lastblock:
543 			if (match_int(args, &option))
544 				return 0;
545 			uopt->lastblock = option;
546 			if (!remount)
547 				uopt->flags |= (1 << UDF_FLAG_LASTBLOCK_SET);
548 			break;
549 		case Opt_anchor:
550 			if (match_int(args, &option))
551 				return 0;
552 			uopt->anchor = option;
553 			break;
554 		case Opt_volume:
555 		case Opt_partition:
556 		case Opt_fileset:
557 		case Opt_rootdir:
558 			/* Ignored (never implemented properly) */
559 			break;
560 		case Opt_utf8:
561 			if (!remount) {
562 				unload_nls(uopt->nls_map);
563 				uopt->nls_map = NULL;
564 			}
565 			break;
566 		case Opt_iocharset:
567 			if (!remount) {
568 				unload_nls(uopt->nls_map);
569 				uopt->nls_map = NULL;
570 			}
571 			/* When nls_map is not loaded then UTF-8 is used */
572 			if (!remount && strcmp(args[0].from, "utf8") != 0) {
573 				uopt->nls_map = load_nls(args[0].from);
574 				if (!uopt->nls_map) {
575 					pr_err("iocharset %s not found\n",
576 						args[0].from);
577 					return 0;
578 				}
579 			}
580 			break;
581 		case Opt_uforget:
582 			uopt->flags |= (1 << UDF_FLAG_UID_FORGET);
583 			break;
584 		case Opt_uignore:
585 		case Opt_gignore:
586 			/* These options are superseeded by uid=<number> */
587 			break;
588 		case Opt_gforget:
589 			uopt->flags |= (1 << UDF_FLAG_GID_FORGET);
590 			break;
591 		case Opt_fmode:
592 			if (match_octal(args, &option))
593 				return 0;
594 			uopt->fmode = option & 0777;
595 			break;
596 		case Opt_dmode:
597 			if (match_octal(args, &option))
598 				return 0;
599 			uopt->dmode = option & 0777;
600 			break;
601 		default:
602 			pr_err("bad mount option \"%s\" or missing value\n", p);
603 			return 0;
604 		}
605 	}
606 	return 1;
607 }
608 
609 static int udf_remount_fs(struct super_block *sb, int *flags, char *options)
610 {
611 	struct udf_options uopt;
612 	struct udf_sb_info *sbi = UDF_SB(sb);
613 	int error = 0;
614 
615 	if (!(*flags & SB_RDONLY) && UDF_QUERY_FLAG(sb, UDF_FLAG_RW_INCOMPAT))
616 		return -EACCES;
617 
618 	sync_filesystem(sb);
619 
620 	uopt.flags = sbi->s_flags;
621 	uopt.uid   = sbi->s_uid;
622 	uopt.gid   = sbi->s_gid;
623 	uopt.umask = sbi->s_umask;
624 	uopt.fmode = sbi->s_fmode;
625 	uopt.dmode = sbi->s_dmode;
626 	uopt.nls_map = NULL;
627 
628 	if (!udf_parse_options(options, &uopt, true))
629 		return -EINVAL;
630 
631 	write_lock(&sbi->s_cred_lock);
632 	sbi->s_flags = uopt.flags;
633 	sbi->s_uid   = uopt.uid;
634 	sbi->s_gid   = uopt.gid;
635 	sbi->s_umask = uopt.umask;
636 	sbi->s_fmode = uopt.fmode;
637 	sbi->s_dmode = uopt.dmode;
638 	write_unlock(&sbi->s_cred_lock);
639 
640 	if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
641 		goto out_unlock;
642 
643 	if (*flags & SB_RDONLY)
644 		udf_close_lvid(sb);
645 	else
646 		udf_open_lvid(sb);
647 
648 out_unlock:
649 	return error;
650 }
651 
652 /*
653  * Check VSD descriptor. Returns -1 in case we are at the end of volume
654  * recognition area, 0 if the descriptor is valid but non-interesting, 1 if
655  * we found one of NSR descriptors we are looking for.
656  */
657 static int identify_vsd(const struct volStructDesc *vsd)
658 {
659 	int ret = 0;
660 
661 	if (!memcmp(vsd->stdIdent, VSD_STD_ID_CD001, VSD_STD_ID_LEN)) {
662 		switch (vsd->structType) {
663 		case 0:
664 			udf_debug("ISO9660 Boot Record found\n");
665 			break;
666 		case 1:
667 			udf_debug("ISO9660 Primary Volume Descriptor found\n");
668 			break;
669 		case 2:
670 			udf_debug("ISO9660 Supplementary Volume Descriptor found\n");
671 			break;
672 		case 3:
673 			udf_debug("ISO9660 Volume Partition Descriptor found\n");
674 			break;
675 		case 255:
676 			udf_debug("ISO9660 Volume Descriptor Set Terminator found\n");
677 			break;
678 		default:
679 			udf_debug("ISO9660 VRS (%u) found\n", vsd->structType);
680 			break;
681 		}
682 	} else if (!memcmp(vsd->stdIdent, VSD_STD_ID_BEA01, VSD_STD_ID_LEN))
683 		; /* ret = 0 */
684 	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_NSR02, VSD_STD_ID_LEN))
685 		ret = 1;
686 	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_NSR03, VSD_STD_ID_LEN))
687 		ret = 1;
688 	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_BOOT2, VSD_STD_ID_LEN))
689 		; /* ret = 0 */
690 	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_CDW02, VSD_STD_ID_LEN))
691 		; /* ret = 0 */
692 	else {
693 		/* TEA01 or invalid id : end of volume recognition area */
694 		ret = -1;
695 	}
696 
697 	return ret;
698 }
699 
700 /*
701  * Check Volume Structure Descriptors (ECMA 167 2/9.1)
702  * We also check any "CD-ROM Volume Descriptor Set" (ECMA 167 2/8.3.1)
703  * @return   1 if NSR02 or NSR03 found,
704  *	    -1 if first sector read error, 0 otherwise
705  */
706 static int udf_check_vsd(struct super_block *sb)
707 {
708 	struct volStructDesc *vsd = NULL;
709 	loff_t sector = VSD_FIRST_SECTOR_OFFSET;
710 	int sectorsize;
711 	struct buffer_head *bh = NULL;
712 	int nsr = 0;
713 	struct udf_sb_info *sbi;
714 	loff_t session_offset;
715 
716 	sbi = UDF_SB(sb);
717 	if (sb->s_blocksize < sizeof(struct volStructDesc))
718 		sectorsize = sizeof(struct volStructDesc);
719 	else
720 		sectorsize = sb->s_blocksize;
721 
722 	session_offset = (loff_t)sbi->s_session << sb->s_blocksize_bits;
723 	sector += session_offset;
724 
725 	udf_debug("Starting at sector %u (%lu byte sectors)\n",
726 		  (unsigned int)(sector >> sb->s_blocksize_bits),
727 		  sb->s_blocksize);
728 	/* Process the sequence (if applicable). The hard limit on the sector
729 	 * offset is arbitrary, hopefully large enough so that all valid UDF
730 	 * filesystems will be recognised. There is no mention of an upper
731 	 * bound to the size of the volume recognition area in the standard.
732 	 *  The limit will prevent the code to read all the sectors of a
733 	 * specially crafted image (like a bluray disc full of CD001 sectors),
734 	 * potentially causing minutes or even hours of uninterruptible I/O
735 	 * activity. This actually happened with uninitialised SSD partitions
736 	 * (all 0xFF) before the check for the limit and all valid IDs were
737 	 * added */
738 	for (; !nsr && sector < VSD_MAX_SECTOR_OFFSET; sector += sectorsize) {
739 		/* Read a block */
740 		bh = sb_bread(sb, sector >> sb->s_blocksize_bits);
741 		if (!bh)
742 			break;
743 
744 		vsd = (struct volStructDesc *)(bh->b_data +
745 					      (sector & (sb->s_blocksize - 1)));
746 		nsr = identify_vsd(vsd);
747 		/* Found NSR or end? */
748 		if (nsr) {
749 			brelse(bh);
750 			break;
751 		}
752 		/*
753 		 * Special handling for improperly formatted VRS (e.g., Win10)
754 		 * where components are separated by 2048 bytes even though
755 		 * sectors are 4K
756 		 */
757 		if (sb->s_blocksize == 4096) {
758 			nsr = identify_vsd(vsd + 1);
759 			/* Ignore unknown IDs... */
760 			if (nsr < 0)
761 				nsr = 0;
762 		}
763 		brelse(bh);
764 	}
765 
766 	if (nsr > 0)
767 		return 1;
768 	else if (!bh && sector - session_offset == VSD_FIRST_SECTOR_OFFSET)
769 		return -1;
770 	else
771 		return 0;
772 }
773 
774 static int udf_verify_domain_identifier(struct super_block *sb,
775 					struct regid *ident, char *dname)
776 {
777 	struct domainIdentSuffix *suffix;
778 
779 	if (memcmp(ident->ident, UDF_ID_COMPLIANT, strlen(UDF_ID_COMPLIANT))) {
780 		udf_warn(sb, "Not OSTA UDF compliant %s descriptor.\n", dname);
781 		goto force_ro;
782 	}
783 	if (ident->flags & ENTITYID_FLAGS_DIRTY) {
784 		udf_warn(sb, "Possibly not OSTA UDF compliant %s descriptor.\n",
785 			 dname);
786 		goto force_ro;
787 	}
788 	suffix = (struct domainIdentSuffix *)ident->identSuffix;
789 	if ((suffix->domainFlags & DOMAIN_FLAGS_HARD_WRITE_PROTECT) ||
790 	    (suffix->domainFlags & DOMAIN_FLAGS_SOFT_WRITE_PROTECT)) {
791 		if (!sb_rdonly(sb)) {
792 			udf_warn(sb, "Descriptor for %s marked write protected."
793 				 " Forcing read only mount.\n", dname);
794 		}
795 		goto force_ro;
796 	}
797 	return 0;
798 
799 force_ro:
800 	if (!sb_rdonly(sb))
801 		return -EACCES;
802 	UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
803 	return 0;
804 }
805 
806 static int udf_load_fileset(struct super_block *sb, struct fileSetDesc *fset,
807 			    struct kernel_lb_addr *root)
808 {
809 	int ret;
810 
811 	ret = udf_verify_domain_identifier(sb, &fset->domainIdent, "file set");
812 	if (ret < 0)
813 		return ret;
814 
815 	*root = lelb_to_cpu(fset->rootDirectoryICB.extLocation);
816 	UDF_SB(sb)->s_serial_number = le16_to_cpu(fset->descTag.tagSerialNum);
817 
818 	udf_debug("Rootdir at block=%u, partition=%u\n",
819 		  root->logicalBlockNum, root->partitionReferenceNum);
820 	return 0;
821 }
822 
823 static int udf_find_fileset(struct super_block *sb,
824 			    struct kernel_lb_addr *fileset,
825 			    struct kernel_lb_addr *root)
826 {
827 	struct buffer_head *bh;
828 	uint16_t ident;
829 	int ret;
830 
831 	if (fileset->logicalBlockNum == 0xFFFFFFFF &&
832 	    fileset->partitionReferenceNum == 0xFFFF)
833 		return -EINVAL;
834 
835 	bh = udf_read_ptagged(sb, fileset, 0, &ident);
836 	if (!bh)
837 		return -EIO;
838 	if (ident != TAG_IDENT_FSD) {
839 		brelse(bh);
840 		return -EINVAL;
841 	}
842 
843 	udf_debug("Fileset at block=%u, partition=%u\n",
844 		  fileset->logicalBlockNum, fileset->partitionReferenceNum);
845 
846 	UDF_SB(sb)->s_partition = fileset->partitionReferenceNum;
847 	ret = udf_load_fileset(sb, (struct fileSetDesc *)bh->b_data, root);
848 	brelse(bh);
849 	return ret;
850 }
851 
852 /*
853  * Load primary Volume Descriptor Sequence
854  *
855  * Return <0 on error, 0 on success. -EAGAIN is special meaning next sequence
856  * should be tried.
857  */
858 static int udf_load_pvoldesc(struct super_block *sb, sector_t block)
859 {
860 	struct primaryVolDesc *pvoldesc;
861 	uint8_t *outstr;
862 	struct buffer_head *bh;
863 	uint16_t ident;
864 	int ret;
865 	struct timestamp *ts;
866 
867 	outstr = kmalloc(128, GFP_NOFS);
868 	if (!outstr)
869 		return -ENOMEM;
870 
871 	bh = udf_read_tagged(sb, block, block, &ident);
872 	if (!bh) {
873 		ret = -EAGAIN;
874 		goto out2;
875 	}
876 
877 	if (ident != TAG_IDENT_PVD) {
878 		ret = -EIO;
879 		goto out_bh;
880 	}
881 
882 	pvoldesc = (struct primaryVolDesc *)bh->b_data;
883 
884 	udf_disk_stamp_to_time(&UDF_SB(sb)->s_record_time,
885 			      pvoldesc->recordingDateAndTime);
886 	ts = &pvoldesc->recordingDateAndTime;
887 	udf_debug("recording time %04u/%02u/%02u %02u:%02u (%x)\n",
888 		  le16_to_cpu(ts->year), ts->month, ts->day, ts->hour,
889 		  ts->minute, le16_to_cpu(ts->typeAndTimezone));
890 
891 	ret = udf_dstrCS0toChar(sb, outstr, 31, pvoldesc->volIdent, 32);
892 	if (ret < 0) {
893 		strcpy(UDF_SB(sb)->s_volume_ident, "InvalidName");
894 		pr_warn("incorrect volume identification, setting to "
895 			"'InvalidName'\n");
896 	} else {
897 		strncpy(UDF_SB(sb)->s_volume_ident, outstr, ret);
898 	}
899 	udf_debug("volIdent[] = '%s'\n", UDF_SB(sb)->s_volume_ident);
900 
901 	ret = udf_dstrCS0toChar(sb, outstr, 127, pvoldesc->volSetIdent, 128);
902 	if (ret < 0) {
903 		ret = 0;
904 		goto out_bh;
905 	}
906 	outstr[ret] = 0;
907 	udf_debug("volSetIdent[] = '%s'\n", outstr);
908 
909 	ret = 0;
910 out_bh:
911 	brelse(bh);
912 out2:
913 	kfree(outstr);
914 	return ret;
915 }
916 
917 struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
918 					u32 meta_file_loc, u32 partition_ref)
919 {
920 	struct kernel_lb_addr addr;
921 	struct inode *metadata_fe;
922 
923 	addr.logicalBlockNum = meta_file_loc;
924 	addr.partitionReferenceNum = partition_ref;
925 
926 	metadata_fe = udf_iget_special(sb, &addr);
927 
928 	if (IS_ERR(metadata_fe)) {
929 		udf_warn(sb, "metadata inode efe not found\n");
930 		return metadata_fe;
931 	}
932 	if (UDF_I(metadata_fe)->i_alloc_type != ICBTAG_FLAG_AD_SHORT) {
933 		udf_warn(sb, "metadata inode efe does not have short allocation descriptors!\n");
934 		iput(metadata_fe);
935 		return ERR_PTR(-EIO);
936 	}
937 
938 	return metadata_fe;
939 }
940 
941 static int udf_load_metadata_files(struct super_block *sb, int partition,
942 				   int type1_index)
943 {
944 	struct udf_sb_info *sbi = UDF_SB(sb);
945 	struct udf_part_map *map;
946 	struct udf_meta_data *mdata;
947 	struct kernel_lb_addr addr;
948 	struct inode *fe;
949 
950 	map = &sbi->s_partmaps[partition];
951 	mdata = &map->s_type_specific.s_metadata;
952 	mdata->s_phys_partition_ref = type1_index;
953 
954 	/* metadata address */
955 	udf_debug("Metadata file location: block = %u part = %u\n",
956 		  mdata->s_meta_file_loc, mdata->s_phys_partition_ref);
957 
958 	fe = udf_find_metadata_inode_efe(sb, mdata->s_meta_file_loc,
959 					 mdata->s_phys_partition_ref);
960 	if (IS_ERR(fe)) {
961 		/* mirror file entry */
962 		udf_debug("Mirror metadata file location: block = %u part = %u\n",
963 			  mdata->s_mirror_file_loc, mdata->s_phys_partition_ref);
964 
965 		fe = udf_find_metadata_inode_efe(sb, mdata->s_mirror_file_loc,
966 						 mdata->s_phys_partition_ref);
967 
968 		if (IS_ERR(fe)) {
969 			udf_err(sb, "Both metadata and mirror metadata inode efe can not found\n");
970 			return PTR_ERR(fe);
971 		}
972 		mdata->s_mirror_fe = fe;
973 	} else
974 		mdata->s_metadata_fe = fe;
975 
976 
977 	/*
978 	 * bitmap file entry
979 	 * Note:
980 	 * Load only if bitmap file location differs from 0xFFFFFFFF (DCN-5102)
981 	*/
982 	if (mdata->s_bitmap_file_loc != 0xFFFFFFFF) {
983 		addr.logicalBlockNum = mdata->s_bitmap_file_loc;
984 		addr.partitionReferenceNum = mdata->s_phys_partition_ref;
985 
986 		udf_debug("Bitmap file location: block = %u part = %u\n",
987 			  addr.logicalBlockNum, addr.partitionReferenceNum);
988 
989 		fe = udf_iget_special(sb, &addr);
990 		if (IS_ERR(fe)) {
991 			if (sb_rdonly(sb))
992 				udf_warn(sb, "bitmap inode efe not found but it's ok since the disc is mounted read-only\n");
993 			else {
994 				udf_err(sb, "bitmap inode efe not found and attempted read-write mount\n");
995 				return PTR_ERR(fe);
996 			}
997 		} else
998 			mdata->s_bitmap_fe = fe;
999 	}
1000 
1001 	udf_debug("udf_load_metadata_files Ok\n");
1002 	return 0;
1003 }
1004 
1005 int udf_compute_nr_groups(struct super_block *sb, u32 partition)
1006 {
1007 	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
1008 	return DIV_ROUND_UP(map->s_partition_len +
1009 			    (sizeof(struct spaceBitmapDesc) << 3),
1010 			    sb->s_blocksize * 8);
1011 }
1012 
1013 static struct udf_bitmap *udf_sb_alloc_bitmap(struct super_block *sb, u32 index)
1014 {
1015 	struct udf_bitmap *bitmap;
1016 	int nr_groups = udf_compute_nr_groups(sb, index);
1017 
1018 	bitmap = kvzalloc(struct_size(bitmap, s_block_bitmap, nr_groups),
1019 			  GFP_KERNEL);
1020 	if (!bitmap)
1021 		return NULL;
1022 
1023 	bitmap->s_nr_groups = nr_groups;
1024 	return bitmap;
1025 }
1026 
1027 static int check_partition_desc(struct super_block *sb,
1028 				struct partitionDesc *p,
1029 				struct udf_part_map *map)
1030 {
1031 	bool umap, utable, fmap, ftable;
1032 	struct partitionHeaderDesc *phd;
1033 
1034 	switch (le32_to_cpu(p->accessType)) {
1035 	case PD_ACCESS_TYPE_READ_ONLY:
1036 	case PD_ACCESS_TYPE_WRITE_ONCE:
1037 	case PD_ACCESS_TYPE_NONE:
1038 		goto force_ro;
1039 	}
1040 
1041 	/* No Partition Header Descriptor? */
1042 	if (strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR02) &&
1043 	    strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR03))
1044 		goto force_ro;
1045 
1046 	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1047 	utable = phd->unallocSpaceTable.extLength;
1048 	umap = phd->unallocSpaceBitmap.extLength;
1049 	ftable = phd->freedSpaceTable.extLength;
1050 	fmap = phd->freedSpaceBitmap.extLength;
1051 
1052 	/* No allocation info? */
1053 	if (!utable && !umap && !ftable && !fmap)
1054 		goto force_ro;
1055 
1056 	/* We don't support blocks that require erasing before overwrite */
1057 	if (ftable || fmap)
1058 		goto force_ro;
1059 	/* UDF 2.60: 2.3.3 - no mixing of tables & bitmaps, no VAT. */
1060 	if (utable && umap)
1061 		goto force_ro;
1062 
1063 	if (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1064 	    map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1065 	    map->s_partition_type == UDF_METADATA_MAP25)
1066 		goto force_ro;
1067 
1068 	return 0;
1069 force_ro:
1070 	if (!sb_rdonly(sb))
1071 		return -EACCES;
1072 	UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1073 	return 0;
1074 }
1075 
1076 static int udf_fill_partdesc_info(struct super_block *sb,
1077 		struct partitionDesc *p, int p_index)
1078 {
1079 	struct udf_part_map *map;
1080 	struct udf_sb_info *sbi = UDF_SB(sb);
1081 	struct partitionHeaderDesc *phd;
1082 	int err;
1083 
1084 	map = &sbi->s_partmaps[p_index];
1085 
1086 	map->s_partition_len = le32_to_cpu(p->partitionLength); /* blocks */
1087 	map->s_partition_root = le32_to_cpu(p->partitionStartingLocation);
1088 
1089 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_READ_ONLY))
1090 		map->s_partition_flags |= UDF_PART_FLAG_READ_ONLY;
1091 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_WRITE_ONCE))
1092 		map->s_partition_flags |= UDF_PART_FLAG_WRITE_ONCE;
1093 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_REWRITABLE))
1094 		map->s_partition_flags |= UDF_PART_FLAG_REWRITABLE;
1095 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_OVERWRITABLE))
1096 		map->s_partition_flags |= UDF_PART_FLAG_OVERWRITABLE;
1097 
1098 	udf_debug("Partition (%d type %x) starts at physical %u, block length %u\n",
1099 		  p_index, map->s_partition_type,
1100 		  map->s_partition_root, map->s_partition_len);
1101 
1102 	err = check_partition_desc(sb, p, map);
1103 	if (err)
1104 		return err;
1105 
1106 	/*
1107 	 * Skip loading allocation info it we cannot ever write to the fs.
1108 	 * This is a correctness thing as we may have decided to force ro mount
1109 	 * to avoid allocation info we don't support.
1110 	 */
1111 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_RW_INCOMPAT))
1112 		return 0;
1113 
1114 	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1115 	if (phd->unallocSpaceTable.extLength) {
1116 		struct kernel_lb_addr loc = {
1117 			.logicalBlockNum = le32_to_cpu(
1118 				phd->unallocSpaceTable.extPosition),
1119 			.partitionReferenceNum = p_index,
1120 		};
1121 		struct inode *inode;
1122 
1123 		inode = udf_iget_special(sb, &loc);
1124 		if (IS_ERR(inode)) {
1125 			udf_debug("cannot load unallocSpaceTable (part %d)\n",
1126 				  p_index);
1127 			return PTR_ERR(inode);
1128 		}
1129 		map->s_uspace.s_table = inode;
1130 		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_TABLE;
1131 		udf_debug("unallocSpaceTable (part %d) @ %lu\n",
1132 			  p_index, map->s_uspace.s_table->i_ino);
1133 	}
1134 
1135 	if (phd->unallocSpaceBitmap.extLength) {
1136 		struct udf_bitmap *bitmap = udf_sb_alloc_bitmap(sb, p_index);
1137 		if (!bitmap)
1138 			return -ENOMEM;
1139 		map->s_uspace.s_bitmap = bitmap;
1140 		bitmap->s_extPosition = le32_to_cpu(
1141 				phd->unallocSpaceBitmap.extPosition);
1142 		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_BITMAP;
1143 		udf_debug("unallocSpaceBitmap (part %d) @ %u\n",
1144 			  p_index, bitmap->s_extPosition);
1145 	}
1146 
1147 	return 0;
1148 }
1149 
1150 static void udf_find_vat_block(struct super_block *sb, int p_index,
1151 			       int type1_index, sector_t start_block)
1152 {
1153 	struct udf_sb_info *sbi = UDF_SB(sb);
1154 	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1155 	sector_t vat_block;
1156 	struct kernel_lb_addr ino;
1157 	struct inode *inode;
1158 
1159 	/*
1160 	 * VAT file entry is in the last recorded block. Some broken disks have
1161 	 * it a few blocks before so try a bit harder...
1162 	 */
1163 	ino.partitionReferenceNum = type1_index;
1164 	for (vat_block = start_block;
1165 	     vat_block >= map->s_partition_root &&
1166 	     vat_block >= start_block - 3; vat_block--) {
1167 		ino.logicalBlockNum = vat_block - map->s_partition_root;
1168 		inode = udf_iget_special(sb, &ino);
1169 		if (!IS_ERR(inode)) {
1170 			sbi->s_vat_inode = inode;
1171 			break;
1172 		}
1173 	}
1174 }
1175 
1176 static int udf_load_vat(struct super_block *sb, int p_index, int type1_index)
1177 {
1178 	struct udf_sb_info *sbi = UDF_SB(sb);
1179 	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1180 	struct buffer_head *bh = NULL;
1181 	struct udf_inode_info *vati;
1182 	struct virtualAllocationTable20 *vat20;
1183 	sector_t blocks = sb_bdev_nr_blocks(sb);
1184 
1185 	udf_find_vat_block(sb, p_index, type1_index, sbi->s_last_block);
1186 	if (!sbi->s_vat_inode &&
1187 	    sbi->s_last_block != blocks - 1) {
1188 		pr_notice("Failed to read VAT inode from the last recorded block (%lu), retrying with the last block of the device (%lu).\n",
1189 			  (unsigned long)sbi->s_last_block,
1190 			  (unsigned long)blocks - 1);
1191 		udf_find_vat_block(sb, p_index, type1_index, blocks - 1);
1192 	}
1193 	if (!sbi->s_vat_inode)
1194 		return -EIO;
1195 
1196 	if (map->s_partition_type == UDF_VIRTUAL_MAP15) {
1197 		map->s_type_specific.s_virtual.s_start_offset = 0;
1198 		map->s_type_specific.s_virtual.s_num_entries =
1199 			(sbi->s_vat_inode->i_size - 36) >> 2;
1200 	} else if (map->s_partition_type == UDF_VIRTUAL_MAP20) {
1201 		vati = UDF_I(sbi->s_vat_inode);
1202 		if (vati->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1203 			int err = 0;
1204 
1205 			bh = udf_bread(sbi->s_vat_inode, 0, 0, &err);
1206 			if (!bh) {
1207 				if (!err)
1208 					err = -EFSCORRUPTED;
1209 				return err;
1210 			}
1211 			vat20 = (struct virtualAllocationTable20 *)bh->b_data;
1212 		} else {
1213 			vat20 = (struct virtualAllocationTable20 *)
1214 							vati->i_data;
1215 		}
1216 
1217 		map->s_type_specific.s_virtual.s_start_offset =
1218 			le16_to_cpu(vat20->lengthHeader);
1219 		map->s_type_specific.s_virtual.s_num_entries =
1220 			(sbi->s_vat_inode->i_size -
1221 				map->s_type_specific.s_virtual.
1222 					s_start_offset) >> 2;
1223 		brelse(bh);
1224 	}
1225 	return 0;
1226 }
1227 
1228 /*
1229  * Load partition descriptor block
1230  *
1231  * Returns <0 on error, 0 on success, -EAGAIN is special - try next descriptor
1232  * sequence.
1233  */
1234 static int udf_load_partdesc(struct super_block *sb, sector_t block)
1235 {
1236 	struct buffer_head *bh;
1237 	struct partitionDesc *p;
1238 	struct udf_part_map *map;
1239 	struct udf_sb_info *sbi = UDF_SB(sb);
1240 	int i, type1_idx;
1241 	uint16_t partitionNumber;
1242 	uint16_t ident;
1243 	int ret;
1244 
1245 	bh = udf_read_tagged(sb, block, block, &ident);
1246 	if (!bh)
1247 		return -EAGAIN;
1248 	if (ident != TAG_IDENT_PD) {
1249 		ret = 0;
1250 		goto out_bh;
1251 	}
1252 
1253 	p = (struct partitionDesc *)bh->b_data;
1254 	partitionNumber = le16_to_cpu(p->partitionNumber);
1255 
1256 	/* First scan for TYPE1 and SPARABLE partitions */
1257 	for (i = 0; i < sbi->s_partitions; i++) {
1258 		map = &sbi->s_partmaps[i];
1259 		udf_debug("Searching map: (%u == %u)\n",
1260 			  map->s_partition_num, partitionNumber);
1261 		if (map->s_partition_num == partitionNumber &&
1262 		    (map->s_partition_type == UDF_TYPE1_MAP15 ||
1263 		     map->s_partition_type == UDF_SPARABLE_MAP15))
1264 			break;
1265 	}
1266 
1267 	if (i >= sbi->s_partitions) {
1268 		udf_debug("Partition (%u) not found in partition map\n",
1269 			  partitionNumber);
1270 		ret = 0;
1271 		goto out_bh;
1272 	}
1273 
1274 	ret = udf_fill_partdesc_info(sb, p, i);
1275 	if (ret < 0)
1276 		goto out_bh;
1277 
1278 	/*
1279 	 * Now rescan for VIRTUAL or METADATA partitions when SPARABLE and
1280 	 * PHYSICAL partitions are already set up
1281 	 */
1282 	type1_idx = i;
1283 	map = NULL; /* supress 'maybe used uninitialized' warning */
1284 	for (i = 0; i < sbi->s_partitions; i++) {
1285 		map = &sbi->s_partmaps[i];
1286 
1287 		if (map->s_partition_num == partitionNumber &&
1288 		    (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1289 		     map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1290 		     map->s_partition_type == UDF_METADATA_MAP25))
1291 			break;
1292 	}
1293 
1294 	if (i >= sbi->s_partitions) {
1295 		ret = 0;
1296 		goto out_bh;
1297 	}
1298 
1299 	ret = udf_fill_partdesc_info(sb, p, i);
1300 	if (ret < 0)
1301 		goto out_bh;
1302 
1303 	if (map->s_partition_type == UDF_METADATA_MAP25) {
1304 		ret = udf_load_metadata_files(sb, i, type1_idx);
1305 		if (ret < 0) {
1306 			udf_err(sb, "error loading MetaData partition map %d\n",
1307 				i);
1308 			goto out_bh;
1309 		}
1310 	} else {
1311 		/*
1312 		 * If we have a partition with virtual map, we don't handle
1313 		 * writing to it (we overwrite blocks instead of relocating
1314 		 * them).
1315 		 */
1316 		if (!sb_rdonly(sb)) {
1317 			ret = -EACCES;
1318 			goto out_bh;
1319 		}
1320 		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1321 		ret = udf_load_vat(sb, i, type1_idx);
1322 		if (ret < 0)
1323 			goto out_bh;
1324 	}
1325 	ret = 0;
1326 out_bh:
1327 	/* In case loading failed, we handle cleanup in udf_fill_super */
1328 	brelse(bh);
1329 	return ret;
1330 }
1331 
1332 static int udf_load_sparable_map(struct super_block *sb,
1333 				 struct udf_part_map *map,
1334 				 struct sparablePartitionMap *spm)
1335 {
1336 	uint32_t loc;
1337 	uint16_t ident;
1338 	struct sparingTable *st;
1339 	struct udf_sparing_data *sdata = &map->s_type_specific.s_sparing;
1340 	int i;
1341 	struct buffer_head *bh;
1342 
1343 	map->s_partition_type = UDF_SPARABLE_MAP15;
1344 	sdata->s_packet_len = le16_to_cpu(spm->packetLength);
1345 	if (!is_power_of_2(sdata->s_packet_len)) {
1346 		udf_err(sb, "error loading logical volume descriptor: "
1347 			"Invalid packet length %u\n",
1348 			(unsigned)sdata->s_packet_len);
1349 		return -EIO;
1350 	}
1351 	if (spm->numSparingTables > 4) {
1352 		udf_err(sb, "error loading logical volume descriptor: "
1353 			"Too many sparing tables (%d)\n",
1354 			(int)spm->numSparingTables);
1355 		return -EIO;
1356 	}
1357 	if (le32_to_cpu(spm->sizeSparingTable) > sb->s_blocksize) {
1358 		udf_err(sb, "error loading logical volume descriptor: "
1359 			"Too big sparing table size (%u)\n",
1360 			le32_to_cpu(spm->sizeSparingTable));
1361 		return -EIO;
1362 	}
1363 
1364 	for (i = 0; i < spm->numSparingTables; i++) {
1365 		loc = le32_to_cpu(spm->locSparingTable[i]);
1366 		bh = udf_read_tagged(sb, loc, loc, &ident);
1367 		if (!bh)
1368 			continue;
1369 
1370 		st = (struct sparingTable *)bh->b_data;
1371 		if (ident != 0 ||
1372 		    strncmp(st->sparingIdent.ident, UDF_ID_SPARING,
1373 			    strlen(UDF_ID_SPARING)) ||
1374 		    sizeof(*st) + le16_to_cpu(st->reallocationTableLen) >
1375 							sb->s_blocksize) {
1376 			brelse(bh);
1377 			continue;
1378 		}
1379 
1380 		sdata->s_spar_map[i] = bh;
1381 	}
1382 	map->s_partition_func = udf_get_pblock_spar15;
1383 	return 0;
1384 }
1385 
1386 static int udf_load_logicalvol(struct super_block *sb, sector_t block,
1387 			       struct kernel_lb_addr *fileset)
1388 {
1389 	struct logicalVolDesc *lvd;
1390 	int i, offset;
1391 	uint8_t type;
1392 	struct udf_sb_info *sbi = UDF_SB(sb);
1393 	struct genericPartitionMap *gpm;
1394 	uint16_t ident;
1395 	struct buffer_head *bh;
1396 	unsigned int table_len;
1397 	int ret;
1398 
1399 	bh = udf_read_tagged(sb, block, block, &ident);
1400 	if (!bh)
1401 		return -EAGAIN;
1402 	BUG_ON(ident != TAG_IDENT_LVD);
1403 	lvd = (struct logicalVolDesc *)bh->b_data;
1404 	table_len = le32_to_cpu(lvd->mapTableLength);
1405 	if (table_len > sb->s_blocksize - sizeof(*lvd)) {
1406 		udf_err(sb, "error loading logical volume descriptor: "
1407 			"Partition table too long (%u > %lu)\n", table_len,
1408 			sb->s_blocksize - sizeof(*lvd));
1409 		ret = -EIO;
1410 		goto out_bh;
1411 	}
1412 
1413 	ret = udf_verify_domain_identifier(sb, &lvd->domainIdent,
1414 					   "logical volume");
1415 	if (ret)
1416 		goto out_bh;
1417 	ret = udf_sb_alloc_partition_maps(sb, le32_to_cpu(lvd->numPartitionMaps));
1418 	if (ret)
1419 		goto out_bh;
1420 
1421 	for (i = 0, offset = 0;
1422 	     i < sbi->s_partitions && offset < table_len;
1423 	     i++, offset += gpm->partitionMapLength) {
1424 		struct udf_part_map *map = &sbi->s_partmaps[i];
1425 		gpm = (struct genericPartitionMap *)
1426 				&(lvd->partitionMaps[offset]);
1427 		type = gpm->partitionMapType;
1428 		if (type == 1) {
1429 			struct genericPartitionMap1 *gpm1 =
1430 				(struct genericPartitionMap1 *)gpm;
1431 			map->s_partition_type = UDF_TYPE1_MAP15;
1432 			map->s_volumeseqnum = le16_to_cpu(gpm1->volSeqNum);
1433 			map->s_partition_num = le16_to_cpu(gpm1->partitionNum);
1434 			map->s_partition_func = NULL;
1435 		} else if (type == 2) {
1436 			struct udfPartitionMap2 *upm2 =
1437 						(struct udfPartitionMap2 *)gpm;
1438 			if (!strncmp(upm2->partIdent.ident, UDF_ID_VIRTUAL,
1439 						strlen(UDF_ID_VIRTUAL))) {
1440 				u16 suf =
1441 					le16_to_cpu(((__le16 *)upm2->partIdent.
1442 							identSuffix)[0]);
1443 				if (suf < 0x0200) {
1444 					map->s_partition_type =
1445 							UDF_VIRTUAL_MAP15;
1446 					map->s_partition_func =
1447 							udf_get_pblock_virt15;
1448 				} else {
1449 					map->s_partition_type =
1450 							UDF_VIRTUAL_MAP20;
1451 					map->s_partition_func =
1452 							udf_get_pblock_virt20;
1453 				}
1454 			} else if (!strncmp(upm2->partIdent.ident,
1455 						UDF_ID_SPARABLE,
1456 						strlen(UDF_ID_SPARABLE))) {
1457 				ret = udf_load_sparable_map(sb, map,
1458 					(struct sparablePartitionMap *)gpm);
1459 				if (ret < 0)
1460 					goto out_bh;
1461 			} else if (!strncmp(upm2->partIdent.ident,
1462 						UDF_ID_METADATA,
1463 						strlen(UDF_ID_METADATA))) {
1464 				struct udf_meta_data *mdata =
1465 					&map->s_type_specific.s_metadata;
1466 				struct metadataPartitionMap *mdm =
1467 						(struct metadataPartitionMap *)
1468 						&(lvd->partitionMaps[offset]);
1469 				udf_debug("Parsing Logical vol part %d type %u  id=%s\n",
1470 					  i, type, UDF_ID_METADATA);
1471 
1472 				map->s_partition_type = UDF_METADATA_MAP25;
1473 				map->s_partition_func = udf_get_pblock_meta25;
1474 
1475 				mdata->s_meta_file_loc   =
1476 					le32_to_cpu(mdm->metadataFileLoc);
1477 				mdata->s_mirror_file_loc =
1478 					le32_to_cpu(mdm->metadataMirrorFileLoc);
1479 				mdata->s_bitmap_file_loc =
1480 					le32_to_cpu(mdm->metadataBitmapFileLoc);
1481 				mdata->s_alloc_unit_size =
1482 					le32_to_cpu(mdm->allocUnitSize);
1483 				mdata->s_align_unit_size =
1484 					le16_to_cpu(mdm->alignUnitSize);
1485 				if (mdm->flags & 0x01)
1486 					mdata->s_flags |= MF_DUPLICATE_MD;
1487 
1488 				udf_debug("Metadata Ident suffix=0x%x\n",
1489 					  le16_to_cpu(*(__le16 *)
1490 						      mdm->partIdent.identSuffix));
1491 				udf_debug("Metadata part num=%u\n",
1492 					  le16_to_cpu(mdm->partitionNum));
1493 				udf_debug("Metadata part alloc unit size=%u\n",
1494 					  le32_to_cpu(mdm->allocUnitSize));
1495 				udf_debug("Metadata file loc=%u\n",
1496 					  le32_to_cpu(mdm->metadataFileLoc));
1497 				udf_debug("Mirror file loc=%u\n",
1498 					  le32_to_cpu(mdm->metadataMirrorFileLoc));
1499 				udf_debug("Bitmap file loc=%u\n",
1500 					  le32_to_cpu(mdm->metadataBitmapFileLoc));
1501 				udf_debug("Flags: %d %u\n",
1502 					  mdata->s_flags, mdm->flags);
1503 			} else {
1504 				udf_debug("Unknown ident: %s\n",
1505 					  upm2->partIdent.ident);
1506 				continue;
1507 			}
1508 			map->s_volumeseqnum = le16_to_cpu(upm2->volSeqNum);
1509 			map->s_partition_num = le16_to_cpu(upm2->partitionNum);
1510 		}
1511 		udf_debug("Partition (%d:%u) type %u on volume %u\n",
1512 			  i, map->s_partition_num, type, map->s_volumeseqnum);
1513 	}
1514 
1515 	if (fileset) {
1516 		struct long_ad *la = (struct long_ad *)&(lvd->logicalVolContentsUse[0]);
1517 
1518 		*fileset = lelb_to_cpu(la->extLocation);
1519 		udf_debug("FileSet found in LogicalVolDesc at block=%u, partition=%u\n",
1520 			  fileset->logicalBlockNum,
1521 			  fileset->partitionReferenceNum);
1522 	}
1523 	if (lvd->integritySeqExt.extLength)
1524 		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
1525 	ret = 0;
1526 
1527 	if (!sbi->s_lvid_bh) {
1528 		/* We can't generate unique IDs without a valid LVID */
1529 		if (sb_rdonly(sb)) {
1530 			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1531 		} else {
1532 			udf_warn(sb, "Damaged or missing LVID, forcing "
1533 				     "readonly mount\n");
1534 			ret = -EACCES;
1535 		}
1536 	}
1537 out_bh:
1538 	brelse(bh);
1539 	return ret;
1540 }
1541 
1542 /*
1543  * Find the prevailing Logical Volume Integrity Descriptor.
1544  */
1545 static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_ad loc)
1546 {
1547 	struct buffer_head *bh, *final_bh;
1548 	uint16_t ident;
1549 	struct udf_sb_info *sbi = UDF_SB(sb);
1550 	struct logicalVolIntegrityDesc *lvid;
1551 	int indirections = 0;
1552 	u32 parts, impuselen;
1553 
1554 	while (++indirections <= UDF_MAX_LVID_NESTING) {
1555 		final_bh = NULL;
1556 		while (loc.extLength > 0 &&
1557 			(bh = udf_read_tagged(sb, loc.extLocation,
1558 					loc.extLocation, &ident))) {
1559 			if (ident != TAG_IDENT_LVID) {
1560 				brelse(bh);
1561 				break;
1562 			}
1563 
1564 			brelse(final_bh);
1565 			final_bh = bh;
1566 
1567 			loc.extLength -= sb->s_blocksize;
1568 			loc.extLocation++;
1569 		}
1570 
1571 		if (!final_bh)
1572 			return;
1573 
1574 		brelse(sbi->s_lvid_bh);
1575 		sbi->s_lvid_bh = final_bh;
1576 
1577 		lvid = (struct logicalVolIntegrityDesc *)final_bh->b_data;
1578 		if (lvid->nextIntegrityExt.extLength == 0)
1579 			goto check;
1580 
1581 		loc = leea_to_cpu(lvid->nextIntegrityExt);
1582 	}
1583 
1584 	udf_warn(sb, "Too many LVID indirections (max %u), ignoring.\n",
1585 		UDF_MAX_LVID_NESTING);
1586 out_err:
1587 	brelse(sbi->s_lvid_bh);
1588 	sbi->s_lvid_bh = NULL;
1589 	return;
1590 check:
1591 	parts = le32_to_cpu(lvid->numOfPartitions);
1592 	impuselen = le32_to_cpu(lvid->lengthOfImpUse);
1593 	if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
1594 	    sizeof(struct logicalVolIntegrityDesc) + impuselen +
1595 	    2 * parts * sizeof(u32) > sb->s_blocksize) {
1596 		udf_warn(sb, "Corrupted LVID (parts=%u, impuselen=%u), "
1597 			 "ignoring.\n", parts, impuselen);
1598 		goto out_err;
1599 	}
1600 }
1601 
1602 /*
1603  * Step for reallocation of table of partition descriptor sequence numbers.
1604  * Must be power of 2.
1605  */
1606 #define PART_DESC_ALLOC_STEP 32
1607 
1608 struct part_desc_seq_scan_data {
1609 	struct udf_vds_record rec;
1610 	u32 partnum;
1611 };
1612 
1613 struct desc_seq_scan_data {
1614 	struct udf_vds_record vds[VDS_POS_LENGTH];
1615 	unsigned int size_part_descs;
1616 	unsigned int num_part_descs;
1617 	struct part_desc_seq_scan_data *part_descs_loc;
1618 };
1619 
1620 static struct udf_vds_record *handle_partition_descriptor(
1621 				struct buffer_head *bh,
1622 				struct desc_seq_scan_data *data)
1623 {
1624 	struct partitionDesc *desc = (struct partitionDesc *)bh->b_data;
1625 	int partnum;
1626 	int i;
1627 
1628 	partnum = le16_to_cpu(desc->partitionNumber);
1629 	for (i = 0; i < data->num_part_descs; i++)
1630 		if (partnum == data->part_descs_loc[i].partnum)
1631 			return &(data->part_descs_loc[i].rec);
1632 	if (data->num_part_descs >= data->size_part_descs) {
1633 		struct part_desc_seq_scan_data *new_loc;
1634 		unsigned int new_size = ALIGN(partnum, PART_DESC_ALLOC_STEP);
1635 
1636 		new_loc = kcalloc(new_size, sizeof(*new_loc), GFP_KERNEL);
1637 		if (!new_loc)
1638 			return ERR_PTR(-ENOMEM);
1639 		memcpy(new_loc, data->part_descs_loc,
1640 		       data->size_part_descs * sizeof(*new_loc));
1641 		kfree(data->part_descs_loc);
1642 		data->part_descs_loc = new_loc;
1643 		data->size_part_descs = new_size;
1644 	}
1645 	return &(data->part_descs_loc[data->num_part_descs++].rec);
1646 }
1647 
1648 
1649 static struct udf_vds_record *get_volume_descriptor_record(uint16_t ident,
1650 		struct buffer_head *bh, struct desc_seq_scan_data *data)
1651 {
1652 	switch (ident) {
1653 	case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1654 		return &(data->vds[VDS_POS_PRIMARY_VOL_DESC]);
1655 	case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1656 		return &(data->vds[VDS_POS_IMP_USE_VOL_DESC]);
1657 	case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1658 		return &(data->vds[VDS_POS_LOGICAL_VOL_DESC]);
1659 	case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1660 		return &(data->vds[VDS_POS_UNALLOC_SPACE_DESC]);
1661 	case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1662 		return handle_partition_descriptor(bh, data);
1663 	}
1664 	return NULL;
1665 }
1666 
1667 /*
1668  * Process a main/reserve volume descriptor sequence.
1669  *   @block		First block of first extent of the sequence.
1670  *   @lastblock		Lastblock of first extent of the sequence.
1671  *   @fileset		There we store extent containing root fileset
1672  *
1673  * Returns <0 on error, 0 on success. -EAGAIN is special - try next descriptor
1674  * sequence
1675  */
1676 static noinline int udf_process_sequence(
1677 		struct super_block *sb,
1678 		sector_t block, sector_t lastblock,
1679 		struct kernel_lb_addr *fileset)
1680 {
1681 	struct buffer_head *bh = NULL;
1682 	struct udf_vds_record *curr;
1683 	struct generic_desc *gd;
1684 	struct volDescPtr *vdp;
1685 	bool done = false;
1686 	uint32_t vdsn;
1687 	uint16_t ident;
1688 	int ret;
1689 	unsigned int indirections = 0;
1690 	struct desc_seq_scan_data data;
1691 	unsigned int i;
1692 
1693 	memset(data.vds, 0, sizeof(struct udf_vds_record) * VDS_POS_LENGTH);
1694 	data.size_part_descs = PART_DESC_ALLOC_STEP;
1695 	data.num_part_descs = 0;
1696 	data.part_descs_loc = kcalloc(data.size_part_descs,
1697 				      sizeof(*data.part_descs_loc),
1698 				      GFP_KERNEL);
1699 	if (!data.part_descs_loc)
1700 		return -ENOMEM;
1701 
1702 	/*
1703 	 * Read the main descriptor sequence and find which descriptors
1704 	 * are in it.
1705 	 */
1706 	for (; (!done && block <= lastblock); block++) {
1707 		bh = udf_read_tagged(sb, block, block, &ident);
1708 		if (!bh)
1709 			break;
1710 
1711 		/* Process each descriptor (ISO 13346 3/8.3-8.4) */
1712 		gd = (struct generic_desc *)bh->b_data;
1713 		vdsn = le32_to_cpu(gd->volDescSeqNum);
1714 		switch (ident) {
1715 		case TAG_IDENT_VDP: /* ISO 13346 3/10.3 */
1716 			if (++indirections > UDF_MAX_TD_NESTING) {
1717 				udf_err(sb, "too many Volume Descriptor "
1718 					"Pointers (max %u supported)\n",
1719 					UDF_MAX_TD_NESTING);
1720 				brelse(bh);
1721 				ret = -EIO;
1722 				goto out;
1723 			}
1724 
1725 			vdp = (struct volDescPtr *)bh->b_data;
1726 			block = le32_to_cpu(vdp->nextVolDescSeqExt.extLocation);
1727 			lastblock = le32_to_cpu(
1728 				vdp->nextVolDescSeqExt.extLength) >>
1729 				sb->s_blocksize_bits;
1730 			lastblock += block - 1;
1731 			/* For loop is going to increment 'block' again */
1732 			block--;
1733 			break;
1734 		case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1735 		case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1736 		case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1737 		case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1738 		case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1739 			curr = get_volume_descriptor_record(ident, bh, &data);
1740 			if (IS_ERR(curr)) {
1741 				brelse(bh);
1742 				ret = PTR_ERR(curr);
1743 				goto out;
1744 			}
1745 			/* Descriptor we don't care about? */
1746 			if (!curr)
1747 				break;
1748 			if (vdsn >= curr->volDescSeqNum) {
1749 				curr->volDescSeqNum = vdsn;
1750 				curr->block = block;
1751 			}
1752 			break;
1753 		case TAG_IDENT_TD: /* ISO 13346 3/10.9 */
1754 			done = true;
1755 			break;
1756 		}
1757 		brelse(bh);
1758 	}
1759 	/*
1760 	 * Now read interesting descriptors again and process them
1761 	 * in a suitable order
1762 	 */
1763 	if (!data.vds[VDS_POS_PRIMARY_VOL_DESC].block) {
1764 		udf_err(sb, "Primary Volume Descriptor not found!\n");
1765 		ret = -EAGAIN;
1766 		goto out;
1767 	}
1768 	ret = udf_load_pvoldesc(sb, data.vds[VDS_POS_PRIMARY_VOL_DESC].block);
1769 	if (ret < 0)
1770 		goto out;
1771 
1772 	if (data.vds[VDS_POS_LOGICAL_VOL_DESC].block) {
1773 		ret = udf_load_logicalvol(sb,
1774 				data.vds[VDS_POS_LOGICAL_VOL_DESC].block,
1775 				fileset);
1776 		if (ret < 0)
1777 			goto out;
1778 	}
1779 
1780 	/* Now handle prevailing Partition Descriptors */
1781 	for (i = 0; i < data.num_part_descs; i++) {
1782 		ret = udf_load_partdesc(sb, data.part_descs_loc[i].rec.block);
1783 		if (ret < 0)
1784 			goto out;
1785 	}
1786 	ret = 0;
1787 out:
1788 	kfree(data.part_descs_loc);
1789 	return ret;
1790 }
1791 
1792 /*
1793  * Load Volume Descriptor Sequence described by anchor in bh
1794  *
1795  * Returns <0 on error, 0 on success
1796  */
1797 static int udf_load_sequence(struct super_block *sb, struct buffer_head *bh,
1798 			     struct kernel_lb_addr *fileset)
1799 {
1800 	struct anchorVolDescPtr *anchor;
1801 	sector_t main_s, main_e, reserve_s, reserve_e;
1802 	int ret;
1803 
1804 	anchor = (struct anchorVolDescPtr *)bh->b_data;
1805 
1806 	/* Locate the main sequence */
1807 	main_s = le32_to_cpu(anchor->mainVolDescSeqExt.extLocation);
1808 	main_e = le32_to_cpu(anchor->mainVolDescSeqExt.extLength);
1809 	main_e = main_e >> sb->s_blocksize_bits;
1810 	main_e += main_s - 1;
1811 
1812 	/* Locate the reserve sequence */
1813 	reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
1814 	reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
1815 	reserve_e = reserve_e >> sb->s_blocksize_bits;
1816 	reserve_e += reserve_s - 1;
1817 
1818 	/* Process the main & reserve sequences */
1819 	/* responsible for finding the PartitionDesc(s) */
1820 	ret = udf_process_sequence(sb, main_s, main_e, fileset);
1821 	if (ret != -EAGAIN)
1822 		return ret;
1823 	udf_sb_free_partitions(sb);
1824 	ret = udf_process_sequence(sb, reserve_s, reserve_e, fileset);
1825 	if (ret < 0) {
1826 		udf_sb_free_partitions(sb);
1827 		/* No sequence was OK, return -EIO */
1828 		if (ret == -EAGAIN)
1829 			ret = -EIO;
1830 	}
1831 	return ret;
1832 }
1833 
1834 /*
1835  * Check whether there is an anchor block in the given block and
1836  * load Volume Descriptor Sequence if so.
1837  *
1838  * Returns <0 on error, 0 on success, -EAGAIN is special - try next anchor
1839  * block
1840  */
1841 static int udf_check_anchor_block(struct super_block *sb, sector_t block,
1842 				  struct kernel_lb_addr *fileset)
1843 {
1844 	struct buffer_head *bh;
1845 	uint16_t ident;
1846 	int ret;
1847 
1848 	bh = udf_read_tagged(sb, block, block, &ident);
1849 	if (!bh)
1850 		return -EAGAIN;
1851 	if (ident != TAG_IDENT_AVDP) {
1852 		brelse(bh);
1853 		return -EAGAIN;
1854 	}
1855 	ret = udf_load_sequence(sb, bh, fileset);
1856 	brelse(bh);
1857 	return ret;
1858 }
1859 
1860 /*
1861  * Search for an anchor volume descriptor pointer.
1862  *
1863  * Returns < 0 on error, 0 on success. -EAGAIN is special - try next set
1864  * of anchors.
1865  */
1866 static int udf_scan_anchors(struct super_block *sb, udf_pblk_t *lastblock,
1867 			    struct kernel_lb_addr *fileset)
1868 {
1869 	udf_pblk_t last[6];
1870 	int i;
1871 	struct udf_sb_info *sbi = UDF_SB(sb);
1872 	int last_count = 0;
1873 	int ret;
1874 
1875 	/* First try user provided anchor */
1876 	if (sbi->s_anchor) {
1877 		ret = udf_check_anchor_block(sb, sbi->s_anchor, fileset);
1878 		if (ret != -EAGAIN)
1879 			return ret;
1880 	}
1881 	/*
1882 	 * according to spec, anchor is in either:
1883 	 *     block 256
1884 	 *     lastblock-256
1885 	 *     lastblock
1886 	 *  however, if the disc isn't closed, it could be 512.
1887 	 */
1888 	ret = udf_check_anchor_block(sb, sbi->s_session + 256, fileset);
1889 	if (ret != -EAGAIN)
1890 		return ret;
1891 	/*
1892 	 * The trouble is which block is the last one. Drives often misreport
1893 	 * this so we try various possibilities.
1894 	 */
1895 	last[last_count++] = *lastblock;
1896 	if (*lastblock >= 1)
1897 		last[last_count++] = *lastblock - 1;
1898 	last[last_count++] = *lastblock + 1;
1899 	if (*lastblock >= 2)
1900 		last[last_count++] = *lastblock - 2;
1901 	if (*lastblock >= 150)
1902 		last[last_count++] = *lastblock - 150;
1903 	if (*lastblock >= 152)
1904 		last[last_count++] = *lastblock - 152;
1905 
1906 	for (i = 0; i < last_count; i++) {
1907 		if (last[i] >= sb_bdev_nr_blocks(sb))
1908 			continue;
1909 		ret = udf_check_anchor_block(sb, last[i], fileset);
1910 		if (ret != -EAGAIN) {
1911 			if (!ret)
1912 				*lastblock = last[i];
1913 			return ret;
1914 		}
1915 		if (last[i] < 256)
1916 			continue;
1917 		ret = udf_check_anchor_block(sb, last[i] - 256, fileset);
1918 		if (ret != -EAGAIN) {
1919 			if (!ret)
1920 				*lastblock = last[i];
1921 			return ret;
1922 		}
1923 	}
1924 
1925 	/* Finally try block 512 in case media is open */
1926 	return udf_check_anchor_block(sb, sbi->s_session + 512, fileset);
1927 }
1928 
1929 /*
1930  * Check Volume Structure Descriptor, find Anchor block and load Volume
1931  * Descriptor Sequence.
1932  *
1933  * Returns < 0 on error, 0 on success. -EAGAIN is special meaning anchor
1934  * block was not found.
1935  */
1936 static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
1937 			int silent, struct kernel_lb_addr *fileset)
1938 {
1939 	struct udf_sb_info *sbi = UDF_SB(sb);
1940 	int nsr = 0;
1941 	int ret;
1942 
1943 	if (!sb_set_blocksize(sb, uopt->blocksize)) {
1944 		if (!silent)
1945 			udf_warn(sb, "Bad block size\n");
1946 		return -EINVAL;
1947 	}
1948 	sbi->s_last_block = uopt->lastblock;
1949 	if (!uopt->novrs) {
1950 		/* Check that it is NSR02 compliant */
1951 		nsr = udf_check_vsd(sb);
1952 		if (!nsr) {
1953 			if (!silent)
1954 				udf_warn(sb, "No VRS found\n");
1955 			return -EINVAL;
1956 		}
1957 		if (nsr == -1)
1958 			udf_debug("Failed to read sector at offset %d. "
1959 				  "Assuming open disc. Skipping validity "
1960 				  "check\n", VSD_FIRST_SECTOR_OFFSET);
1961 		if (!sbi->s_last_block)
1962 			sbi->s_last_block = udf_get_last_block(sb);
1963 	} else {
1964 		udf_debug("Validity check skipped because of novrs option\n");
1965 	}
1966 
1967 	/* Look for anchor block and load Volume Descriptor Sequence */
1968 	sbi->s_anchor = uopt->anchor;
1969 	ret = udf_scan_anchors(sb, &sbi->s_last_block, fileset);
1970 	if (ret < 0) {
1971 		if (!silent && ret == -EAGAIN)
1972 			udf_warn(sb, "No anchor found\n");
1973 		return ret;
1974 	}
1975 	return 0;
1976 }
1977 
1978 static void udf_finalize_lvid(struct logicalVolIntegrityDesc *lvid)
1979 {
1980 	struct timespec64 ts;
1981 
1982 	ktime_get_real_ts64(&ts);
1983 	udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
1984 	lvid->descTag.descCRC = cpu_to_le16(
1985 		crc_itu_t(0, (char *)lvid + sizeof(struct tag),
1986 			le16_to_cpu(lvid->descTag.descCRCLength)));
1987 	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
1988 }
1989 
1990 static void udf_open_lvid(struct super_block *sb)
1991 {
1992 	struct udf_sb_info *sbi = UDF_SB(sb);
1993 	struct buffer_head *bh = sbi->s_lvid_bh;
1994 	struct logicalVolIntegrityDesc *lvid;
1995 	struct logicalVolIntegrityDescImpUse *lvidiu;
1996 
1997 	if (!bh)
1998 		return;
1999 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2000 	lvidiu = udf_sb_lvidiu(sb);
2001 	if (!lvidiu)
2002 		return;
2003 
2004 	mutex_lock(&sbi->s_alloc_mutex);
2005 	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2006 	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2007 	if (le32_to_cpu(lvid->integrityType) == LVID_INTEGRITY_TYPE_CLOSE)
2008 		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
2009 	else
2010 		UDF_SET_FLAG(sb, UDF_FLAG_INCONSISTENT);
2011 
2012 	udf_finalize_lvid(lvid);
2013 	mark_buffer_dirty(bh);
2014 	sbi->s_lvid_dirty = 0;
2015 	mutex_unlock(&sbi->s_alloc_mutex);
2016 	/* Make opening of filesystem visible on the media immediately */
2017 	sync_dirty_buffer(bh);
2018 }
2019 
2020 static void udf_close_lvid(struct super_block *sb)
2021 {
2022 	struct udf_sb_info *sbi = UDF_SB(sb);
2023 	struct buffer_head *bh = sbi->s_lvid_bh;
2024 	struct logicalVolIntegrityDesc *lvid;
2025 	struct logicalVolIntegrityDescImpUse *lvidiu;
2026 
2027 	if (!bh)
2028 		return;
2029 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2030 	lvidiu = udf_sb_lvidiu(sb);
2031 	if (!lvidiu)
2032 		return;
2033 
2034 	mutex_lock(&sbi->s_alloc_mutex);
2035 	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2036 	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2037 	if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
2038 		lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
2039 	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
2040 		lvidiu->minUDFReadRev = cpu_to_le16(sbi->s_udfrev);
2041 	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFWriteRev))
2042 		lvidiu->minUDFWriteRev = cpu_to_le16(sbi->s_udfrev);
2043 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_INCONSISTENT))
2044 		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);
2045 
2046 	/*
2047 	 * We set buffer uptodate unconditionally here to avoid spurious
2048 	 * warnings from mark_buffer_dirty() when previous EIO has marked
2049 	 * the buffer as !uptodate
2050 	 */
2051 	set_buffer_uptodate(bh);
2052 	udf_finalize_lvid(lvid);
2053 	mark_buffer_dirty(bh);
2054 	sbi->s_lvid_dirty = 0;
2055 	mutex_unlock(&sbi->s_alloc_mutex);
2056 	/* Make closing of filesystem visible on the media immediately */
2057 	sync_dirty_buffer(bh);
2058 }
2059 
2060 u64 lvid_get_unique_id(struct super_block *sb)
2061 {
2062 	struct buffer_head *bh;
2063 	struct udf_sb_info *sbi = UDF_SB(sb);
2064 	struct logicalVolIntegrityDesc *lvid;
2065 	struct logicalVolHeaderDesc *lvhd;
2066 	u64 uniqueID;
2067 	u64 ret;
2068 
2069 	bh = sbi->s_lvid_bh;
2070 	if (!bh)
2071 		return 0;
2072 
2073 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2074 	lvhd = (struct logicalVolHeaderDesc *)lvid->logicalVolContentsUse;
2075 
2076 	mutex_lock(&sbi->s_alloc_mutex);
2077 	ret = uniqueID = le64_to_cpu(lvhd->uniqueID);
2078 	if (!(++uniqueID & 0xFFFFFFFF))
2079 		uniqueID += 16;
2080 	lvhd->uniqueID = cpu_to_le64(uniqueID);
2081 	udf_updated_lvid(sb);
2082 	mutex_unlock(&sbi->s_alloc_mutex);
2083 
2084 	return ret;
2085 }
2086 
2087 static int udf_fill_super(struct super_block *sb, void *options, int silent)
2088 {
2089 	int ret = -EINVAL;
2090 	struct inode *inode = NULL;
2091 	struct udf_options uopt;
2092 	struct kernel_lb_addr rootdir, fileset;
2093 	struct udf_sb_info *sbi;
2094 	bool lvid_open = false;
2095 
2096 	uopt.flags = (1 << UDF_FLAG_USE_AD_IN_ICB) | (1 << UDF_FLAG_STRICT);
2097 	/* By default we'll use overflow[ug]id when UDF inode [ug]id == -1 */
2098 	uopt.uid = make_kuid(current_user_ns(), overflowuid);
2099 	uopt.gid = make_kgid(current_user_ns(), overflowgid);
2100 	uopt.umask = 0;
2101 	uopt.fmode = UDF_INVALID_MODE;
2102 	uopt.dmode = UDF_INVALID_MODE;
2103 	uopt.nls_map = NULL;
2104 
2105 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2106 	if (!sbi)
2107 		return -ENOMEM;
2108 
2109 	sb->s_fs_info = sbi;
2110 
2111 	mutex_init(&sbi->s_alloc_mutex);
2112 
2113 	if (!udf_parse_options((char *)options, &uopt, false))
2114 		goto parse_options_failure;
2115 
2116 	fileset.logicalBlockNum = 0xFFFFFFFF;
2117 	fileset.partitionReferenceNum = 0xFFFF;
2118 
2119 	sbi->s_flags = uopt.flags;
2120 	sbi->s_uid = uopt.uid;
2121 	sbi->s_gid = uopt.gid;
2122 	sbi->s_umask = uopt.umask;
2123 	sbi->s_fmode = uopt.fmode;
2124 	sbi->s_dmode = uopt.dmode;
2125 	sbi->s_nls_map = uopt.nls_map;
2126 	rwlock_init(&sbi->s_cred_lock);
2127 
2128 	if (uopt.session == 0xFFFFFFFF)
2129 		sbi->s_session = udf_get_last_session(sb);
2130 	else
2131 		sbi->s_session = uopt.session;
2132 
2133 	udf_debug("Multi-session=%d\n", sbi->s_session);
2134 
2135 	/* Fill in the rest of the superblock */
2136 	sb->s_op = &udf_sb_ops;
2137 	sb->s_export_op = &udf_export_ops;
2138 
2139 	sb->s_magic = UDF_SUPER_MAGIC;
2140 	sb->s_time_gran = 1000;
2141 
2142 	if (uopt.flags & (1 << UDF_FLAG_BLOCKSIZE_SET)) {
2143 		ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2144 	} else {
2145 		uopt.blocksize = bdev_logical_block_size(sb->s_bdev);
2146 		while (uopt.blocksize <= 4096) {
2147 			ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2148 			if (ret < 0) {
2149 				if (!silent && ret != -EACCES) {
2150 					pr_notice("Scanning with blocksize %u failed\n",
2151 						  uopt.blocksize);
2152 				}
2153 				brelse(sbi->s_lvid_bh);
2154 				sbi->s_lvid_bh = NULL;
2155 				/*
2156 				 * EACCES is special - we want to propagate to
2157 				 * upper layers that we cannot handle RW mount.
2158 				 */
2159 				if (ret == -EACCES)
2160 					break;
2161 			} else
2162 				break;
2163 
2164 			uopt.blocksize <<= 1;
2165 		}
2166 	}
2167 	if (ret < 0) {
2168 		if (ret == -EAGAIN) {
2169 			udf_warn(sb, "No partition found (1)\n");
2170 			ret = -EINVAL;
2171 		}
2172 		goto error_out;
2173 	}
2174 
2175 	udf_debug("Lastblock=%u\n", sbi->s_last_block);
2176 
2177 	if (sbi->s_lvid_bh) {
2178 		struct logicalVolIntegrityDescImpUse *lvidiu =
2179 							udf_sb_lvidiu(sb);
2180 		uint16_t minUDFReadRev;
2181 		uint16_t minUDFWriteRev;
2182 
2183 		if (!lvidiu) {
2184 			ret = -EINVAL;
2185 			goto error_out;
2186 		}
2187 		minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev);
2188 		minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev);
2189 		if (minUDFReadRev > UDF_MAX_READ_VERSION) {
2190 			udf_err(sb, "minUDFReadRev=%x (max is %x)\n",
2191 				minUDFReadRev,
2192 				UDF_MAX_READ_VERSION);
2193 			ret = -EINVAL;
2194 			goto error_out;
2195 		} else if (minUDFWriteRev > UDF_MAX_WRITE_VERSION) {
2196 			if (!sb_rdonly(sb)) {
2197 				ret = -EACCES;
2198 				goto error_out;
2199 			}
2200 			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2201 		}
2202 
2203 		sbi->s_udfrev = minUDFWriteRev;
2204 
2205 		if (minUDFReadRev >= UDF_VERS_USE_EXTENDED_FE)
2206 			UDF_SET_FLAG(sb, UDF_FLAG_USE_EXTENDED_FE);
2207 		if (minUDFReadRev >= UDF_VERS_USE_STREAMS)
2208 			UDF_SET_FLAG(sb, UDF_FLAG_USE_STREAMS);
2209 	}
2210 
2211 	if (!sbi->s_partitions) {
2212 		udf_warn(sb, "No partition found (2)\n");
2213 		ret = -EINVAL;
2214 		goto error_out;
2215 	}
2216 
2217 	if (sbi->s_partmaps[sbi->s_partition].s_partition_flags &
2218 			UDF_PART_FLAG_READ_ONLY) {
2219 		if (!sb_rdonly(sb)) {
2220 			ret = -EACCES;
2221 			goto error_out;
2222 		}
2223 		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2224 	}
2225 
2226 	ret = udf_find_fileset(sb, &fileset, &rootdir);
2227 	if (ret < 0) {
2228 		udf_warn(sb, "No fileset found\n");
2229 		goto error_out;
2230 	}
2231 
2232 	if (!silent) {
2233 		struct timestamp ts;
2234 		udf_time_to_disk_stamp(&ts, sbi->s_record_time);
2235 		udf_info("Mounting volume '%s', timestamp %04u/%02u/%02u %02u:%02u (%x)\n",
2236 			 sbi->s_volume_ident,
2237 			 le16_to_cpu(ts.year), ts.month, ts.day,
2238 			 ts.hour, ts.minute, le16_to_cpu(ts.typeAndTimezone));
2239 	}
2240 	if (!sb_rdonly(sb)) {
2241 		udf_open_lvid(sb);
2242 		lvid_open = true;
2243 	}
2244 
2245 	/* Assign the root inode */
2246 	/* assign inodes by physical block number */
2247 	/* perhaps it's not extensible enough, but for now ... */
2248 	inode = udf_iget(sb, &rootdir);
2249 	if (IS_ERR(inode)) {
2250 		udf_err(sb, "Error in udf_iget, block=%u, partition=%u\n",
2251 		       rootdir.logicalBlockNum, rootdir.partitionReferenceNum);
2252 		ret = PTR_ERR(inode);
2253 		goto error_out;
2254 	}
2255 
2256 	/* Allocate a dentry for the root inode */
2257 	sb->s_root = d_make_root(inode);
2258 	if (!sb->s_root) {
2259 		udf_err(sb, "Couldn't allocate root dentry\n");
2260 		ret = -ENOMEM;
2261 		goto error_out;
2262 	}
2263 	sb->s_maxbytes = UDF_MAX_FILESIZE;
2264 	sb->s_max_links = UDF_MAX_LINKS;
2265 	return 0;
2266 
2267 error_out:
2268 	iput(sbi->s_vat_inode);
2269 parse_options_failure:
2270 	unload_nls(uopt.nls_map);
2271 	if (lvid_open)
2272 		udf_close_lvid(sb);
2273 	brelse(sbi->s_lvid_bh);
2274 	udf_sb_free_partitions(sb);
2275 	kfree(sbi);
2276 	sb->s_fs_info = NULL;
2277 
2278 	return ret;
2279 }
2280 
2281 void _udf_err(struct super_block *sb, const char *function,
2282 	      const char *fmt, ...)
2283 {
2284 	struct va_format vaf;
2285 	va_list args;
2286 
2287 	va_start(args, fmt);
2288 
2289 	vaf.fmt = fmt;
2290 	vaf.va = &args;
2291 
2292 	pr_err("error (device %s): %s: %pV", sb->s_id, function, &vaf);
2293 
2294 	va_end(args);
2295 }
2296 
2297 void _udf_warn(struct super_block *sb, const char *function,
2298 	       const char *fmt, ...)
2299 {
2300 	struct va_format vaf;
2301 	va_list args;
2302 
2303 	va_start(args, fmt);
2304 
2305 	vaf.fmt = fmt;
2306 	vaf.va = &args;
2307 
2308 	pr_warn("warning (device %s): %s: %pV", sb->s_id, function, &vaf);
2309 
2310 	va_end(args);
2311 }
2312 
2313 static void udf_put_super(struct super_block *sb)
2314 {
2315 	struct udf_sb_info *sbi;
2316 
2317 	sbi = UDF_SB(sb);
2318 
2319 	iput(sbi->s_vat_inode);
2320 	unload_nls(sbi->s_nls_map);
2321 	if (!sb_rdonly(sb))
2322 		udf_close_lvid(sb);
2323 	brelse(sbi->s_lvid_bh);
2324 	udf_sb_free_partitions(sb);
2325 	mutex_destroy(&sbi->s_alloc_mutex);
2326 	kfree(sb->s_fs_info);
2327 	sb->s_fs_info = NULL;
2328 }
2329 
2330 static int udf_sync_fs(struct super_block *sb, int wait)
2331 {
2332 	struct udf_sb_info *sbi = UDF_SB(sb);
2333 
2334 	mutex_lock(&sbi->s_alloc_mutex);
2335 	if (sbi->s_lvid_dirty) {
2336 		struct buffer_head *bh = sbi->s_lvid_bh;
2337 		struct logicalVolIntegrityDesc *lvid;
2338 
2339 		lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2340 		udf_finalize_lvid(lvid);
2341 
2342 		/*
2343 		 * Blockdevice will be synced later so we don't have to submit
2344 		 * the buffer for IO
2345 		 */
2346 		mark_buffer_dirty(bh);
2347 		sbi->s_lvid_dirty = 0;
2348 	}
2349 	mutex_unlock(&sbi->s_alloc_mutex);
2350 
2351 	return 0;
2352 }
2353 
2354 static int udf_statfs(struct dentry *dentry, struct kstatfs *buf)
2355 {
2356 	struct super_block *sb = dentry->d_sb;
2357 	struct udf_sb_info *sbi = UDF_SB(sb);
2358 	struct logicalVolIntegrityDescImpUse *lvidiu;
2359 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
2360 
2361 	lvidiu = udf_sb_lvidiu(sb);
2362 	buf->f_type = UDF_SUPER_MAGIC;
2363 	buf->f_bsize = sb->s_blocksize;
2364 	buf->f_blocks = sbi->s_partmaps[sbi->s_partition].s_partition_len;
2365 	buf->f_bfree = udf_count_free(sb);
2366 	buf->f_bavail = buf->f_bfree;
2367 	/*
2368 	 * Let's pretend each free block is also a free 'inode' since UDF does
2369 	 * not have separate preallocated table of inodes.
2370 	 */
2371 	buf->f_files = (lvidiu != NULL ? (le32_to_cpu(lvidiu->numFiles) +
2372 					  le32_to_cpu(lvidiu->numDirs)) : 0)
2373 			+ buf->f_bfree;
2374 	buf->f_ffree = buf->f_bfree;
2375 	buf->f_namelen = UDF_NAME_LEN;
2376 	buf->f_fsid = u64_to_fsid(id);
2377 
2378 	return 0;
2379 }
2380 
2381 static unsigned int udf_count_free_bitmap(struct super_block *sb,
2382 					  struct udf_bitmap *bitmap)
2383 {
2384 	struct buffer_head *bh = NULL;
2385 	unsigned int accum = 0;
2386 	int index;
2387 	udf_pblk_t block = 0, newblock;
2388 	struct kernel_lb_addr loc;
2389 	uint32_t bytes;
2390 	uint8_t *ptr;
2391 	uint16_t ident;
2392 	struct spaceBitmapDesc *bm;
2393 
2394 	loc.logicalBlockNum = bitmap->s_extPosition;
2395 	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
2396 	bh = udf_read_ptagged(sb, &loc, 0, &ident);
2397 
2398 	if (!bh) {
2399 		udf_err(sb, "udf_count_free failed\n");
2400 		goto out;
2401 	} else if (ident != TAG_IDENT_SBD) {
2402 		brelse(bh);
2403 		udf_err(sb, "udf_count_free failed\n");
2404 		goto out;
2405 	}
2406 
2407 	bm = (struct spaceBitmapDesc *)bh->b_data;
2408 	bytes = le32_to_cpu(bm->numOfBytes);
2409 	index = sizeof(struct spaceBitmapDesc); /* offset in first block only */
2410 	ptr = (uint8_t *)bh->b_data;
2411 
2412 	while (bytes > 0) {
2413 		u32 cur_bytes = min_t(u32, bytes, sb->s_blocksize - index);
2414 		accum += bitmap_weight((const unsigned long *)(ptr + index),
2415 					cur_bytes * 8);
2416 		bytes -= cur_bytes;
2417 		if (bytes) {
2418 			brelse(bh);
2419 			newblock = udf_get_lb_pblock(sb, &loc, ++block);
2420 			bh = sb_bread(sb, newblock);
2421 			if (!bh) {
2422 				udf_debug("read failed\n");
2423 				goto out;
2424 			}
2425 			index = 0;
2426 			ptr = (uint8_t *)bh->b_data;
2427 		}
2428 	}
2429 	brelse(bh);
2430 out:
2431 	return accum;
2432 }
2433 
2434 static unsigned int udf_count_free_table(struct super_block *sb,
2435 					 struct inode *table)
2436 {
2437 	unsigned int accum = 0;
2438 	uint32_t elen;
2439 	struct kernel_lb_addr eloc;
2440 	struct extent_position epos;
2441 
2442 	mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
2443 	epos.block = UDF_I(table)->i_location;
2444 	epos.offset = sizeof(struct unallocSpaceEntry);
2445 	epos.bh = NULL;
2446 
2447 	while (udf_next_aext(table, &epos, &eloc, &elen, 1) != -1)
2448 		accum += (elen >> table->i_sb->s_blocksize_bits);
2449 
2450 	brelse(epos.bh);
2451 	mutex_unlock(&UDF_SB(sb)->s_alloc_mutex);
2452 
2453 	return accum;
2454 }
2455 
2456 static unsigned int udf_count_free(struct super_block *sb)
2457 {
2458 	unsigned int accum = 0;
2459 	struct udf_sb_info *sbi = UDF_SB(sb);
2460 	struct udf_part_map *map;
2461 	unsigned int part = sbi->s_partition;
2462 	int ptype = sbi->s_partmaps[part].s_partition_type;
2463 
2464 	if (ptype == UDF_METADATA_MAP25) {
2465 		part = sbi->s_partmaps[part].s_type_specific.s_metadata.
2466 							s_phys_partition_ref;
2467 	} else if (ptype == UDF_VIRTUAL_MAP15 || ptype == UDF_VIRTUAL_MAP20) {
2468 		/*
2469 		 * Filesystems with VAT are append-only and we cannot write to
2470  		 * them. Let's just report 0 here.
2471 		 */
2472 		return 0;
2473 	}
2474 
2475 	if (sbi->s_lvid_bh) {
2476 		struct logicalVolIntegrityDesc *lvid =
2477 			(struct logicalVolIntegrityDesc *)
2478 			sbi->s_lvid_bh->b_data;
2479 		if (le32_to_cpu(lvid->numOfPartitions) > part) {
2480 			accum = le32_to_cpu(
2481 					lvid->freeSpaceTable[part]);
2482 			if (accum == 0xFFFFFFFF)
2483 				accum = 0;
2484 		}
2485 	}
2486 
2487 	if (accum)
2488 		return accum;
2489 
2490 	map = &sbi->s_partmaps[part];
2491 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
2492 		accum += udf_count_free_bitmap(sb,
2493 					       map->s_uspace.s_bitmap);
2494 	}
2495 	if (accum)
2496 		return accum;
2497 
2498 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
2499 		accum += udf_count_free_table(sb,
2500 					      map->s_uspace.s_table);
2501 	}
2502 	return accum;
2503 }
2504 
2505 MODULE_AUTHOR("Ben Fennema");
2506 MODULE_DESCRIPTION("Universal Disk Format Filesystem");
2507 MODULE_LICENSE("GPL");
2508 module_init(init_udf_fs)
2509 module_exit(exit_udf_fs)
2510