xref: /kernel/linux/linux-5.10/fs/udf/super.c (revision 8c2ecf20)
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 *    https://www.ecma.ch/
15 *    https://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#include <linux/iversion.h>
61
62#include "udf_sb.h"
63#include "udf_i.h"
64
65#include <linux/init.h>
66#include <linux/uaccess.h>
67
68enum {
69	VDS_POS_PRIMARY_VOL_DESC,
70	VDS_POS_UNALLOC_SPACE_DESC,
71	VDS_POS_LOGICAL_VOL_DESC,
72	VDS_POS_IMP_USE_VOL_DESC,
73	VDS_POS_LENGTH
74};
75
76#define VSD_FIRST_SECTOR_OFFSET		32768
77#define VSD_MAX_SECTOR_OFFSET		0x800000
78
79/*
80 * Maximum number of Terminating Descriptor / Logical Volume Integrity
81 * Descriptor redirections. The chosen numbers are arbitrary - just that we
82 * hopefully don't limit any real use of rewritten inode on write-once media
83 * but avoid looping for too long on corrupted media.
84 */
85#define UDF_MAX_TD_NESTING 64
86#define UDF_MAX_LVID_NESTING 1000
87
88enum { UDF_MAX_LINKS = 0xffff };
89
90/* These are the "meat" - everything else is stuffing */
91static int udf_fill_super(struct super_block *, void *, int);
92static void udf_put_super(struct super_block *);
93static int udf_sync_fs(struct super_block *, int);
94static int udf_remount_fs(struct super_block *, int *, char *);
95static void udf_load_logicalvolint(struct super_block *, struct kernel_extent_ad);
96static void udf_open_lvid(struct super_block *);
97static void udf_close_lvid(struct super_block *);
98static unsigned int udf_count_free(struct super_block *);
99static int udf_statfs(struct dentry *, struct kstatfs *);
100static int udf_show_options(struct seq_file *, struct dentry *);
101
102struct logicalVolIntegrityDescImpUse *udf_sb_lvidiu(struct super_block *sb)
103{
104	struct logicalVolIntegrityDesc *lvid;
105	unsigned int partnum;
106	unsigned int offset;
107
108	if (!UDF_SB(sb)->s_lvid_bh)
109		return NULL;
110	lvid = (struct logicalVolIntegrityDesc *)UDF_SB(sb)->s_lvid_bh->b_data;
111	partnum = le32_to_cpu(lvid->numOfPartitions);
112	/* The offset is to skip freeSpaceTable and sizeTable arrays */
113	offset = partnum * 2 * sizeof(uint32_t);
114	return (struct logicalVolIntegrityDescImpUse *)
115					(((uint8_t *)(lvid + 1)) + offset);
116}
117
118/* UDF filesystem type */
119static struct dentry *udf_mount(struct file_system_type *fs_type,
120		      int flags, const char *dev_name, void *data)
121{
122	return mount_bdev(fs_type, flags, dev_name, data, udf_fill_super);
123}
124
125static struct file_system_type udf_fstype = {
126	.owner		= THIS_MODULE,
127	.name		= "udf",
128	.mount		= udf_mount,
129	.kill_sb	= kill_block_super,
130	.fs_flags	= FS_REQUIRES_DEV,
131};
132MODULE_ALIAS_FS("udf");
133
134static struct kmem_cache *udf_inode_cachep;
135
136static struct inode *udf_alloc_inode(struct super_block *sb)
137{
138	struct udf_inode_info *ei;
139	ei = kmem_cache_alloc(udf_inode_cachep, GFP_KERNEL);
140	if (!ei)
141		return NULL;
142
143	ei->i_unique = 0;
144	ei->i_lenExtents = 0;
145	ei->i_lenStreams = 0;
146	ei->i_next_alloc_block = 0;
147	ei->i_next_alloc_goal = 0;
148	ei->i_strat4096 = 0;
149	ei->i_streamdir = 0;
150	ei->i_hidden = 0;
151	init_rwsem(&ei->i_data_sem);
152	ei->cached_extent.lstart = -1;
153	spin_lock_init(&ei->i_extent_cache_lock);
154	inode_set_iversion(&ei->vfs_inode, 1);
155
156	return &ei->vfs_inode;
157}
158
159static void udf_free_in_core_inode(struct inode *inode)
160{
161	kmem_cache_free(udf_inode_cachep, UDF_I(inode));
162}
163
164static void init_once(void *foo)
165{
166	struct udf_inode_info *ei = (struct udf_inode_info *)foo;
167
168	ei->i_data = NULL;
169	inode_init_once(&ei->vfs_inode);
170}
171
172static int __init init_inodecache(void)
173{
174	udf_inode_cachep = kmem_cache_create("udf_inode_cache",
175					     sizeof(struct udf_inode_info),
176					     0, (SLAB_RECLAIM_ACCOUNT |
177						 SLAB_MEM_SPREAD |
178						 SLAB_ACCOUNT),
179					     init_once);
180	if (!udf_inode_cachep)
181		return -ENOMEM;
182	return 0;
183}
184
185static void destroy_inodecache(void)
186{
187	/*
188	 * Make sure all delayed rcu free inodes are flushed before we
189	 * destroy cache.
190	 */
191	rcu_barrier();
192	kmem_cache_destroy(udf_inode_cachep);
193}
194
195/* Superblock operations */
196static const struct super_operations udf_sb_ops = {
197	.alloc_inode	= udf_alloc_inode,
198	.free_inode	= udf_free_in_core_inode,
199	.write_inode	= udf_write_inode,
200	.evict_inode	= udf_evict_inode,
201	.put_super	= udf_put_super,
202	.sync_fs	= udf_sync_fs,
203	.statfs		= udf_statfs,
204	.remount_fs	= udf_remount_fs,
205	.show_options	= udf_show_options,
206};
207
208struct udf_options {
209	unsigned char novrs;
210	unsigned int blocksize;
211	unsigned int session;
212	unsigned int lastblock;
213	unsigned int anchor;
214	unsigned int flags;
215	umode_t umask;
216	kgid_t gid;
217	kuid_t uid;
218	umode_t fmode;
219	umode_t dmode;
220	struct nls_table *nls_map;
221};
222
223static int __init init_udf_fs(void)
224{
225	int err;
226
227	err = init_inodecache();
228	if (err)
229		goto out1;
230	err = register_filesystem(&udf_fstype);
231	if (err)
232		goto out;
233
234	return 0;
235
236out:
237	destroy_inodecache();
238
239out1:
240	return err;
241}
242
243static void __exit exit_udf_fs(void)
244{
245	unregister_filesystem(&udf_fstype);
246	destroy_inodecache();
247}
248
249static int udf_sb_alloc_partition_maps(struct super_block *sb, u32 count)
250{
251	struct udf_sb_info *sbi = UDF_SB(sb);
252
253	sbi->s_partmaps = kcalloc(count, sizeof(*sbi->s_partmaps), GFP_KERNEL);
254	if (!sbi->s_partmaps) {
255		sbi->s_partitions = 0;
256		return -ENOMEM;
257	}
258
259	sbi->s_partitions = count;
260	return 0;
261}
262
263static void udf_sb_free_bitmap(struct udf_bitmap *bitmap)
264{
265	int i;
266	int nr_groups = bitmap->s_nr_groups;
267
268	for (i = 0; i < nr_groups; i++)
269		brelse(bitmap->s_block_bitmap[i]);
270
271	kvfree(bitmap);
272}
273
274static void udf_free_partition(struct udf_part_map *map)
275{
276	int i;
277	struct udf_meta_data *mdata;
278
279	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
280		iput(map->s_uspace.s_table);
281	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
282		udf_sb_free_bitmap(map->s_uspace.s_bitmap);
283	if (map->s_partition_type == UDF_SPARABLE_MAP15)
284		for (i = 0; i < 4; i++)
285			brelse(map->s_type_specific.s_sparing.s_spar_map[i]);
286	else if (map->s_partition_type == UDF_METADATA_MAP25) {
287		mdata = &map->s_type_specific.s_metadata;
288		iput(mdata->s_metadata_fe);
289		mdata->s_metadata_fe = NULL;
290
291		iput(mdata->s_mirror_fe);
292		mdata->s_mirror_fe = NULL;
293
294		iput(mdata->s_bitmap_fe);
295		mdata->s_bitmap_fe = NULL;
296	}
297}
298
299static void udf_sb_free_partitions(struct super_block *sb)
300{
301	struct udf_sb_info *sbi = UDF_SB(sb);
302	int i;
303
304	if (!sbi->s_partmaps)
305		return;
306	for (i = 0; i < sbi->s_partitions; i++)
307		udf_free_partition(&sbi->s_partmaps[i]);
308	kfree(sbi->s_partmaps);
309	sbi->s_partmaps = NULL;
310}
311
312static int udf_show_options(struct seq_file *seq, struct dentry *root)
313{
314	struct super_block *sb = root->d_sb;
315	struct udf_sb_info *sbi = UDF_SB(sb);
316
317	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT))
318		seq_puts(seq, ",nostrict");
319	if (UDF_QUERY_FLAG(sb, UDF_FLAG_BLOCKSIZE_SET))
320		seq_printf(seq, ",bs=%lu", sb->s_blocksize);
321	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
322		seq_puts(seq, ",unhide");
323	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
324		seq_puts(seq, ",undelete");
325	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_USE_AD_IN_ICB))
326		seq_puts(seq, ",noadinicb");
327	if (UDF_QUERY_FLAG(sb, UDF_FLAG_USE_SHORT_AD))
328		seq_puts(seq, ",shortad");
329	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_FORGET))
330		seq_puts(seq, ",uid=forget");
331	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_FORGET))
332		seq_puts(seq, ",gid=forget");
333	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET))
334		seq_printf(seq, ",uid=%u", from_kuid(&init_user_ns, sbi->s_uid));
335	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET))
336		seq_printf(seq, ",gid=%u", from_kgid(&init_user_ns, sbi->s_gid));
337	if (sbi->s_umask != 0)
338		seq_printf(seq, ",umask=%ho", sbi->s_umask);
339	if (sbi->s_fmode != UDF_INVALID_MODE)
340		seq_printf(seq, ",mode=%ho", sbi->s_fmode);
341	if (sbi->s_dmode != UDF_INVALID_MODE)
342		seq_printf(seq, ",dmode=%ho", sbi->s_dmode);
343	if (UDF_QUERY_FLAG(sb, UDF_FLAG_SESSION_SET))
344		seq_printf(seq, ",session=%d", sbi->s_session);
345	if (UDF_QUERY_FLAG(sb, UDF_FLAG_LASTBLOCK_SET))
346		seq_printf(seq, ",lastblock=%u", sbi->s_last_block);
347	if (sbi->s_anchor != 0)
348		seq_printf(seq, ",anchor=%u", sbi->s_anchor);
349	if (sbi->s_nls_map)
350		seq_printf(seq, ",iocharset=%s", sbi->s_nls_map->charset);
351	else
352		seq_puts(seq, ",iocharset=utf8");
353
354	return 0;
355}
356
357/*
358 * udf_parse_options
359 *
360 * PURPOSE
361 *	Parse mount options.
362 *
363 * DESCRIPTION
364 *	The following mount options are supported:
365 *
366 *	gid=		Set the default group.
367 *	umask=		Set the default umask.
368 *	mode=		Set the default file permissions.
369 *	dmode=		Set the default directory permissions.
370 *	uid=		Set the default user.
371 *	bs=		Set the block size.
372 *	unhide		Show otherwise hidden files.
373 *	undelete	Show deleted files in lists.
374 *	adinicb		Embed data in the inode (default)
375 *	noadinicb	Don't embed data in the inode
376 *	shortad		Use short ad's
377 *	longad		Use long ad's (default)
378 *	nostrict	Unset strict conformance
379 *	iocharset=	Set the NLS character set
380 *
381 *	The remaining are for debugging and disaster recovery:
382 *
383 *	novrs		Skip volume sequence recognition
384 *
385 *	The following expect a offset from 0.
386 *
387 *	session=	Set the CDROM session (default= last session)
388 *	anchor=		Override standard anchor location. (default= 256)
389 *	volume=		Override the VolumeDesc location. (unused)
390 *	partition=	Override the PartitionDesc location. (unused)
391 *	lastblock=	Set the last block of the filesystem/
392 *
393 *	The following expect a offset from the partition root.
394 *
395 *	fileset=	Override the fileset block location. (unused)
396 *	rootdir=	Override the root directory location. (unused)
397 *		WARNING: overriding the rootdir to a non-directory may
398 *		yield highly unpredictable results.
399 *
400 * PRE-CONDITIONS
401 *	options		Pointer to mount options string.
402 *	uopts		Pointer to mount options variable.
403 *
404 * POST-CONDITIONS
405 *	<return>	1	Mount options parsed okay.
406 *	<return>	0	Error parsing mount options.
407 *
408 * HISTORY
409 *	July 1, 1997 - Andrew E. Mileski
410 *	Written, tested, and released.
411 */
412
413enum {
414	Opt_novrs, Opt_nostrict, Opt_bs, Opt_unhide, Opt_undelete,
415	Opt_noadinicb, Opt_adinicb, Opt_shortad, Opt_longad,
416	Opt_gid, Opt_uid, Opt_umask, Opt_session, Opt_lastblock,
417	Opt_anchor, Opt_volume, Opt_partition, Opt_fileset,
418	Opt_rootdir, Opt_utf8, Opt_iocharset,
419	Opt_err, Opt_uforget, Opt_uignore, Opt_gforget, Opt_gignore,
420	Opt_fmode, Opt_dmode
421};
422
423static const match_table_t tokens = {
424	{Opt_novrs,	"novrs"},
425	{Opt_nostrict,	"nostrict"},
426	{Opt_bs,	"bs=%u"},
427	{Opt_unhide,	"unhide"},
428	{Opt_undelete,	"undelete"},
429	{Opt_noadinicb,	"noadinicb"},
430	{Opt_adinicb,	"adinicb"},
431	{Opt_shortad,	"shortad"},
432	{Opt_longad,	"longad"},
433	{Opt_uforget,	"uid=forget"},
434	{Opt_uignore,	"uid=ignore"},
435	{Opt_gforget,	"gid=forget"},
436	{Opt_gignore,	"gid=ignore"},
437	{Opt_gid,	"gid=%u"},
438	{Opt_uid,	"uid=%u"},
439	{Opt_umask,	"umask=%o"},
440	{Opt_session,	"session=%u"},
441	{Opt_lastblock,	"lastblock=%u"},
442	{Opt_anchor,	"anchor=%u"},
443	{Opt_volume,	"volume=%u"},
444	{Opt_partition,	"partition=%u"},
445	{Opt_fileset,	"fileset=%u"},
446	{Opt_rootdir,	"rootdir=%u"},
447	{Opt_utf8,	"utf8"},
448	{Opt_iocharset,	"iocharset=%s"},
449	{Opt_fmode,     "mode=%o"},
450	{Opt_dmode,     "dmode=%o"},
451	{Opt_err,	NULL}
452};
453
454static int udf_parse_options(char *options, struct udf_options *uopt,
455			     bool remount)
456{
457	char *p;
458	int option;
459
460	uopt->novrs = 0;
461	uopt->session = 0xFFFFFFFF;
462	uopt->lastblock = 0;
463	uopt->anchor = 0;
464
465	if (!options)
466		return 1;
467
468	while ((p = strsep(&options, ",")) != NULL) {
469		substring_t args[MAX_OPT_ARGS];
470		int token;
471		unsigned n;
472		if (!*p)
473			continue;
474
475		token = match_token(p, tokens, args);
476		switch (token) {
477		case Opt_novrs:
478			uopt->novrs = 1;
479			break;
480		case Opt_bs:
481			if (match_int(&args[0], &option))
482				return 0;
483			n = option;
484			if (n != 512 && n != 1024 && n != 2048 && n != 4096)
485				return 0;
486			uopt->blocksize = n;
487			uopt->flags |= (1 << UDF_FLAG_BLOCKSIZE_SET);
488			break;
489		case Opt_unhide:
490			uopt->flags |= (1 << UDF_FLAG_UNHIDE);
491			break;
492		case Opt_undelete:
493			uopt->flags |= (1 << UDF_FLAG_UNDELETE);
494			break;
495		case Opt_noadinicb:
496			uopt->flags &= ~(1 << UDF_FLAG_USE_AD_IN_ICB);
497			break;
498		case Opt_adinicb:
499			uopt->flags |= (1 << UDF_FLAG_USE_AD_IN_ICB);
500			break;
501		case Opt_shortad:
502			uopt->flags |= (1 << UDF_FLAG_USE_SHORT_AD);
503			break;
504		case Opt_longad:
505			uopt->flags &= ~(1 << UDF_FLAG_USE_SHORT_AD);
506			break;
507		case Opt_gid:
508			if (match_int(args, &option))
509				return 0;
510			uopt->gid = make_kgid(current_user_ns(), option);
511			if (!gid_valid(uopt->gid))
512				return 0;
513			uopt->flags |= (1 << UDF_FLAG_GID_SET);
514			break;
515		case Opt_uid:
516			if (match_int(args, &option))
517				return 0;
518			uopt->uid = make_kuid(current_user_ns(), option);
519			if (!uid_valid(uopt->uid))
520				return 0;
521			uopt->flags |= (1 << UDF_FLAG_UID_SET);
522			break;
523		case Opt_umask:
524			if (match_octal(args, &option))
525				return 0;
526			uopt->umask = option;
527			break;
528		case Opt_nostrict:
529			uopt->flags &= ~(1 << UDF_FLAG_STRICT);
530			break;
531		case Opt_session:
532			if (match_int(args, &option))
533				return 0;
534			uopt->session = option;
535			if (!remount)
536				uopt->flags |= (1 << UDF_FLAG_SESSION_SET);
537			break;
538		case Opt_lastblock:
539			if (match_int(args, &option))
540				return 0;
541			uopt->lastblock = option;
542			if (!remount)
543				uopt->flags |= (1 << UDF_FLAG_LASTBLOCK_SET);
544			break;
545		case Opt_anchor:
546			if (match_int(args, &option))
547				return 0;
548			uopt->anchor = option;
549			break;
550		case Opt_volume:
551		case Opt_partition:
552		case Opt_fileset:
553		case Opt_rootdir:
554			/* Ignored (never implemented properly) */
555			break;
556		case Opt_utf8:
557			if (!remount) {
558				unload_nls(uopt->nls_map);
559				uopt->nls_map = NULL;
560			}
561			break;
562		case Opt_iocharset:
563			if (!remount) {
564				unload_nls(uopt->nls_map);
565				uopt->nls_map = NULL;
566			}
567			/* When nls_map is not loaded then UTF-8 is used */
568			if (!remount && strcmp(args[0].from, "utf8") != 0) {
569				uopt->nls_map = load_nls(args[0].from);
570				if (!uopt->nls_map) {
571					pr_err("iocharset %s not found\n",
572						args[0].from);
573					return 0;
574				}
575			}
576			break;
577		case Opt_uforget:
578			uopt->flags |= (1 << UDF_FLAG_UID_FORGET);
579			break;
580		case Opt_uignore:
581		case Opt_gignore:
582			/* These options are superseeded by uid=<number> */
583			break;
584		case Opt_gforget:
585			uopt->flags |= (1 << UDF_FLAG_GID_FORGET);
586			break;
587		case Opt_fmode:
588			if (match_octal(args, &option))
589				return 0;
590			uopt->fmode = option & 0777;
591			break;
592		case Opt_dmode:
593			if (match_octal(args, &option))
594				return 0;
595			uopt->dmode = option & 0777;
596			break;
597		default:
598			pr_err("bad mount option \"%s\" or missing value\n", p);
599			return 0;
600		}
601	}
602	return 1;
603}
604
605static int udf_remount_fs(struct super_block *sb, int *flags, char *options)
606{
607	struct udf_options uopt;
608	struct udf_sb_info *sbi = UDF_SB(sb);
609	int error = 0;
610
611	if (!(*flags & SB_RDONLY) && UDF_QUERY_FLAG(sb, UDF_FLAG_RW_INCOMPAT))
612		return -EACCES;
613
614	sync_filesystem(sb);
615
616	uopt.flags = sbi->s_flags;
617	uopt.uid   = sbi->s_uid;
618	uopt.gid   = sbi->s_gid;
619	uopt.umask = sbi->s_umask;
620	uopt.fmode = sbi->s_fmode;
621	uopt.dmode = sbi->s_dmode;
622	uopt.nls_map = NULL;
623
624	if (!udf_parse_options(options, &uopt, true))
625		return -EINVAL;
626
627	write_lock(&sbi->s_cred_lock);
628	sbi->s_flags = uopt.flags;
629	sbi->s_uid   = uopt.uid;
630	sbi->s_gid   = uopt.gid;
631	sbi->s_umask = uopt.umask;
632	sbi->s_fmode = uopt.fmode;
633	sbi->s_dmode = uopt.dmode;
634	write_unlock(&sbi->s_cred_lock);
635
636	if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
637		goto out_unlock;
638
639	if (*flags & SB_RDONLY)
640		udf_close_lvid(sb);
641	else
642		udf_open_lvid(sb);
643
644out_unlock:
645	return error;
646}
647
648/*
649 * Check VSD descriptor. Returns -1 in case we are at the end of volume
650 * recognition area, 0 if the descriptor is valid but non-interesting, 1 if
651 * we found one of NSR descriptors we are looking for.
652 */
653static int identify_vsd(const struct volStructDesc *vsd)
654{
655	int ret = 0;
656
657	if (!memcmp(vsd->stdIdent, VSD_STD_ID_CD001, VSD_STD_ID_LEN)) {
658		switch (vsd->structType) {
659		case 0:
660			udf_debug("ISO9660 Boot Record found\n");
661			break;
662		case 1:
663			udf_debug("ISO9660 Primary Volume Descriptor found\n");
664			break;
665		case 2:
666			udf_debug("ISO9660 Supplementary Volume Descriptor found\n");
667			break;
668		case 3:
669			udf_debug("ISO9660 Volume Partition Descriptor found\n");
670			break;
671		case 255:
672			udf_debug("ISO9660 Volume Descriptor Set Terminator found\n");
673			break;
674		default:
675			udf_debug("ISO9660 VRS (%u) found\n", vsd->structType);
676			break;
677		}
678	} else if (!memcmp(vsd->stdIdent, VSD_STD_ID_BEA01, VSD_STD_ID_LEN))
679		; /* ret = 0 */
680	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_NSR02, VSD_STD_ID_LEN))
681		ret = 1;
682	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_NSR03, VSD_STD_ID_LEN))
683		ret = 1;
684	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_BOOT2, VSD_STD_ID_LEN))
685		; /* ret = 0 */
686	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_CDW02, VSD_STD_ID_LEN))
687		; /* ret = 0 */
688	else {
689		/* TEA01 or invalid id : end of volume recognition area */
690		ret = -1;
691	}
692
693	return ret;
694}
695
696/*
697 * Check Volume Structure Descriptors (ECMA 167 2/9.1)
698 * We also check any "CD-ROM Volume Descriptor Set" (ECMA 167 2/8.3.1)
699 * @return   1 if NSR02 or NSR03 found,
700 *	    -1 if first sector read error, 0 otherwise
701 */
702static int udf_check_vsd(struct super_block *sb)
703{
704	struct volStructDesc *vsd = NULL;
705	loff_t sector = VSD_FIRST_SECTOR_OFFSET;
706	int sectorsize;
707	struct buffer_head *bh = NULL;
708	int nsr = 0;
709	struct udf_sb_info *sbi;
710	loff_t session_offset;
711
712	sbi = UDF_SB(sb);
713	if (sb->s_blocksize < sizeof(struct volStructDesc))
714		sectorsize = sizeof(struct volStructDesc);
715	else
716		sectorsize = sb->s_blocksize;
717
718	session_offset = (loff_t)sbi->s_session << sb->s_blocksize_bits;
719	sector += session_offset;
720
721	udf_debug("Starting at sector %u (%lu byte sectors)\n",
722		  (unsigned int)(sector >> sb->s_blocksize_bits),
723		  sb->s_blocksize);
724	/* Process the sequence (if applicable). The hard limit on the sector
725	 * offset is arbitrary, hopefully large enough so that all valid UDF
726	 * filesystems will be recognised. There is no mention of an upper
727	 * bound to the size of the volume recognition area in the standard.
728	 *  The limit will prevent the code to read all the sectors of a
729	 * specially crafted image (like a bluray disc full of CD001 sectors),
730	 * potentially causing minutes or even hours of uninterruptible I/O
731	 * activity. This actually happened with uninitialised SSD partitions
732	 * (all 0xFF) before the check for the limit and all valid IDs were
733	 * added */
734	for (; !nsr && sector < VSD_MAX_SECTOR_OFFSET; sector += sectorsize) {
735		/* Read a block */
736		bh = udf_tread(sb, sector >> sb->s_blocksize_bits);
737		if (!bh)
738			break;
739
740		vsd = (struct volStructDesc *)(bh->b_data +
741					      (sector & (sb->s_blocksize - 1)));
742		nsr = identify_vsd(vsd);
743		/* Found NSR or end? */
744		if (nsr) {
745			brelse(bh);
746			break;
747		}
748		/*
749		 * Special handling for improperly formatted VRS (e.g., Win10)
750		 * where components are separated by 2048 bytes even though
751		 * sectors are 4K
752		 */
753		if (sb->s_blocksize == 4096) {
754			nsr = identify_vsd(vsd + 1);
755			/* Ignore unknown IDs... */
756			if (nsr < 0)
757				nsr = 0;
758		}
759		brelse(bh);
760	}
761
762	if (nsr > 0)
763		return 1;
764	else if (!bh && sector - session_offset == VSD_FIRST_SECTOR_OFFSET)
765		return -1;
766	else
767		return 0;
768}
769
770static int udf_verify_domain_identifier(struct super_block *sb,
771					struct regid *ident, char *dname)
772{
773	struct domainIdentSuffix *suffix;
774
775	if (memcmp(ident->ident, UDF_ID_COMPLIANT, strlen(UDF_ID_COMPLIANT))) {
776		udf_warn(sb, "Not OSTA UDF compliant %s descriptor.\n", dname);
777		goto force_ro;
778	}
779	if (ident->flags & ENTITYID_FLAGS_DIRTY) {
780		udf_warn(sb, "Possibly not OSTA UDF compliant %s descriptor.\n",
781			 dname);
782		goto force_ro;
783	}
784	suffix = (struct domainIdentSuffix *)ident->identSuffix;
785	if ((suffix->domainFlags & DOMAIN_FLAGS_HARD_WRITE_PROTECT) ||
786	    (suffix->domainFlags & DOMAIN_FLAGS_SOFT_WRITE_PROTECT)) {
787		if (!sb_rdonly(sb)) {
788			udf_warn(sb, "Descriptor for %s marked write protected."
789				 " Forcing read only mount.\n", dname);
790		}
791		goto force_ro;
792	}
793	return 0;
794
795force_ro:
796	if (!sb_rdonly(sb))
797		return -EACCES;
798	UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
799	return 0;
800}
801
802static int udf_load_fileset(struct super_block *sb, struct fileSetDesc *fset,
803			    struct kernel_lb_addr *root)
804{
805	int ret;
806
807	ret = udf_verify_domain_identifier(sb, &fset->domainIdent, "file set");
808	if (ret < 0)
809		return ret;
810
811	*root = lelb_to_cpu(fset->rootDirectoryICB.extLocation);
812	UDF_SB(sb)->s_serial_number = le16_to_cpu(fset->descTag.tagSerialNum);
813
814	udf_debug("Rootdir at block=%u, partition=%u\n",
815		  root->logicalBlockNum, root->partitionReferenceNum);
816	return 0;
817}
818
819static int udf_find_fileset(struct super_block *sb,
820			    struct kernel_lb_addr *fileset,
821			    struct kernel_lb_addr *root)
822{
823	struct buffer_head *bh = NULL;
824	uint16_t ident;
825	int ret;
826
827	if (fileset->logicalBlockNum == 0xFFFFFFFF &&
828	    fileset->partitionReferenceNum == 0xFFFF)
829		return -EINVAL;
830
831	bh = udf_read_ptagged(sb, fileset, 0, &ident);
832	if (!bh)
833		return -EIO;
834	if (ident != TAG_IDENT_FSD) {
835		brelse(bh);
836		return -EINVAL;
837	}
838
839	udf_debug("Fileset at block=%u, partition=%u\n",
840		  fileset->logicalBlockNum, fileset->partitionReferenceNum);
841
842	UDF_SB(sb)->s_partition = fileset->partitionReferenceNum;
843	ret = udf_load_fileset(sb, (struct fileSetDesc *)bh->b_data, root);
844	brelse(bh);
845	return ret;
846}
847
848/*
849 * Load primary Volume Descriptor Sequence
850 *
851 * Return <0 on error, 0 on success. -EAGAIN is special meaning next sequence
852 * should be tried.
853 */
854static int udf_load_pvoldesc(struct super_block *sb, sector_t block)
855{
856	struct primaryVolDesc *pvoldesc;
857	uint8_t *outstr;
858	struct buffer_head *bh;
859	uint16_t ident;
860	int ret;
861	struct timestamp *ts;
862
863	outstr = kmalloc(128, GFP_NOFS);
864	if (!outstr)
865		return -ENOMEM;
866
867	bh = udf_read_tagged(sb, block, block, &ident);
868	if (!bh) {
869		ret = -EAGAIN;
870		goto out2;
871	}
872
873	if (ident != TAG_IDENT_PVD) {
874		ret = -EIO;
875		goto out_bh;
876	}
877
878	pvoldesc = (struct primaryVolDesc *)bh->b_data;
879
880	udf_disk_stamp_to_time(&UDF_SB(sb)->s_record_time,
881			      pvoldesc->recordingDateAndTime);
882	ts = &pvoldesc->recordingDateAndTime;
883	udf_debug("recording time %04u/%02u/%02u %02u:%02u (%x)\n",
884		  le16_to_cpu(ts->year), ts->month, ts->day, ts->hour,
885		  ts->minute, le16_to_cpu(ts->typeAndTimezone));
886
887	ret = udf_dstrCS0toChar(sb, outstr, 31, pvoldesc->volIdent, 32);
888	if (ret < 0) {
889		strcpy(UDF_SB(sb)->s_volume_ident, "InvalidName");
890		pr_warn("incorrect volume identification, setting to "
891			"'InvalidName'\n");
892	} else {
893		strncpy(UDF_SB(sb)->s_volume_ident, outstr, ret);
894	}
895	udf_debug("volIdent[] = '%s'\n", UDF_SB(sb)->s_volume_ident);
896
897	ret = udf_dstrCS0toChar(sb, outstr, 127, pvoldesc->volSetIdent, 128);
898	if (ret < 0) {
899		ret = 0;
900		goto out_bh;
901	}
902	outstr[ret] = 0;
903	udf_debug("volSetIdent[] = '%s'\n", outstr);
904
905	ret = 0;
906out_bh:
907	brelse(bh);
908out2:
909	kfree(outstr);
910	return ret;
911}
912
913struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
914					u32 meta_file_loc, u32 partition_ref)
915{
916	struct kernel_lb_addr addr;
917	struct inode *metadata_fe;
918
919	addr.logicalBlockNum = meta_file_loc;
920	addr.partitionReferenceNum = partition_ref;
921
922	metadata_fe = udf_iget_special(sb, &addr);
923
924	if (IS_ERR(metadata_fe)) {
925		udf_warn(sb, "metadata inode efe not found\n");
926		return metadata_fe;
927	}
928	if (UDF_I(metadata_fe)->i_alloc_type != ICBTAG_FLAG_AD_SHORT) {
929		udf_warn(sb, "metadata inode efe does not have short allocation descriptors!\n");
930		iput(metadata_fe);
931		return ERR_PTR(-EIO);
932	}
933
934	return metadata_fe;
935}
936
937static int udf_load_metadata_files(struct super_block *sb, int partition,
938				   int type1_index)
939{
940	struct udf_sb_info *sbi = UDF_SB(sb);
941	struct udf_part_map *map;
942	struct udf_meta_data *mdata;
943	struct kernel_lb_addr addr;
944	struct inode *fe;
945
946	map = &sbi->s_partmaps[partition];
947	mdata = &map->s_type_specific.s_metadata;
948	mdata->s_phys_partition_ref = type1_index;
949
950	/* metadata address */
951	udf_debug("Metadata file location: block = %u part = %u\n",
952		  mdata->s_meta_file_loc, mdata->s_phys_partition_ref);
953
954	fe = udf_find_metadata_inode_efe(sb, mdata->s_meta_file_loc,
955					 mdata->s_phys_partition_ref);
956	if (IS_ERR(fe)) {
957		/* mirror file entry */
958		udf_debug("Mirror metadata file location: block = %u part = %u\n",
959			  mdata->s_mirror_file_loc, mdata->s_phys_partition_ref);
960
961		fe = udf_find_metadata_inode_efe(sb, mdata->s_mirror_file_loc,
962						 mdata->s_phys_partition_ref);
963
964		if (IS_ERR(fe)) {
965			udf_err(sb, "Both metadata and mirror metadata inode efe can not found\n");
966			return PTR_ERR(fe);
967		}
968		mdata->s_mirror_fe = fe;
969	} else
970		mdata->s_metadata_fe = fe;
971
972
973	/*
974	 * bitmap file entry
975	 * Note:
976	 * Load only if bitmap file location differs from 0xFFFFFFFF (DCN-5102)
977	*/
978	if (mdata->s_bitmap_file_loc != 0xFFFFFFFF) {
979		addr.logicalBlockNum = mdata->s_bitmap_file_loc;
980		addr.partitionReferenceNum = mdata->s_phys_partition_ref;
981
982		udf_debug("Bitmap file location: block = %u part = %u\n",
983			  addr.logicalBlockNum, addr.partitionReferenceNum);
984
985		fe = udf_iget_special(sb, &addr);
986		if (IS_ERR(fe)) {
987			if (sb_rdonly(sb))
988				udf_warn(sb, "bitmap inode efe not found but it's ok since the disc is mounted read-only\n");
989			else {
990				udf_err(sb, "bitmap inode efe not found and attempted read-write mount\n");
991				return PTR_ERR(fe);
992			}
993		} else
994			mdata->s_bitmap_fe = fe;
995	}
996
997	udf_debug("udf_load_metadata_files Ok\n");
998	return 0;
999}
1000
1001int udf_compute_nr_groups(struct super_block *sb, u32 partition)
1002{
1003	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
1004	return DIV_ROUND_UP(map->s_partition_len +
1005			    (sizeof(struct spaceBitmapDesc) << 3),
1006			    sb->s_blocksize * 8);
1007}
1008
1009static struct udf_bitmap *udf_sb_alloc_bitmap(struct super_block *sb, u32 index)
1010{
1011	struct udf_bitmap *bitmap;
1012	int nr_groups = udf_compute_nr_groups(sb, index);
1013
1014	bitmap = kvzalloc(struct_size(bitmap, s_block_bitmap, nr_groups),
1015			  GFP_KERNEL);
1016	if (!bitmap)
1017		return NULL;
1018
1019	bitmap->s_nr_groups = nr_groups;
1020	return bitmap;
1021}
1022
1023static int check_partition_desc(struct super_block *sb,
1024				struct partitionDesc *p,
1025				struct udf_part_map *map)
1026{
1027	bool umap, utable, fmap, ftable;
1028	struct partitionHeaderDesc *phd;
1029
1030	switch (le32_to_cpu(p->accessType)) {
1031	case PD_ACCESS_TYPE_READ_ONLY:
1032	case PD_ACCESS_TYPE_WRITE_ONCE:
1033	case PD_ACCESS_TYPE_NONE:
1034		goto force_ro;
1035	}
1036
1037	/* No Partition Header Descriptor? */
1038	if (strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR02) &&
1039	    strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR03))
1040		goto force_ro;
1041
1042	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1043	utable = phd->unallocSpaceTable.extLength;
1044	umap = phd->unallocSpaceBitmap.extLength;
1045	ftable = phd->freedSpaceTable.extLength;
1046	fmap = phd->freedSpaceBitmap.extLength;
1047
1048	/* No allocation info? */
1049	if (!utable && !umap && !ftable && !fmap)
1050		goto force_ro;
1051
1052	/* We don't support blocks that require erasing before overwrite */
1053	if (ftable || fmap)
1054		goto force_ro;
1055	/* UDF 2.60: 2.3.3 - no mixing of tables & bitmaps, no VAT. */
1056	if (utable && umap)
1057		goto force_ro;
1058
1059	if (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1060	    map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1061	    map->s_partition_type == UDF_METADATA_MAP25)
1062		goto force_ro;
1063
1064	return 0;
1065force_ro:
1066	if (!sb_rdonly(sb))
1067		return -EACCES;
1068	UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1069	return 0;
1070}
1071
1072static int udf_fill_partdesc_info(struct super_block *sb,
1073		struct partitionDesc *p, int p_index)
1074{
1075	struct udf_part_map *map;
1076	struct udf_sb_info *sbi = UDF_SB(sb);
1077	struct partitionHeaderDesc *phd;
1078	int err;
1079
1080	map = &sbi->s_partmaps[p_index];
1081
1082	map->s_partition_len = le32_to_cpu(p->partitionLength); /* blocks */
1083	map->s_partition_root = le32_to_cpu(p->partitionStartingLocation);
1084
1085	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_READ_ONLY))
1086		map->s_partition_flags |= UDF_PART_FLAG_READ_ONLY;
1087	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_WRITE_ONCE))
1088		map->s_partition_flags |= UDF_PART_FLAG_WRITE_ONCE;
1089	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_REWRITABLE))
1090		map->s_partition_flags |= UDF_PART_FLAG_REWRITABLE;
1091	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_OVERWRITABLE))
1092		map->s_partition_flags |= UDF_PART_FLAG_OVERWRITABLE;
1093
1094	udf_debug("Partition (%d type %x) starts at physical %u, block length %u\n",
1095		  p_index, map->s_partition_type,
1096		  map->s_partition_root, map->s_partition_len);
1097
1098	err = check_partition_desc(sb, p, map);
1099	if (err)
1100		return err;
1101
1102	/*
1103	 * Skip loading allocation info it we cannot ever write to the fs.
1104	 * This is a correctness thing as we may have decided to force ro mount
1105	 * to avoid allocation info we don't support.
1106	 */
1107	if (UDF_QUERY_FLAG(sb, UDF_FLAG_RW_INCOMPAT))
1108		return 0;
1109
1110	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1111	if (phd->unallocSpaceTable.extLength) {
1112		struct kernel_lb_addr loc = {
1113			.logicalBlockNum = le32_to_cpu(
1114				phd->unallocSpaceTable.extPosition),
1115			.partitionReferenceNum = p_index,
1116		};
1117		struct inode *inode;
1118
1119		inode = udf_iget_special(sb, &loc);
1120		if (IS_ERR(inode)) {
1121			udf_debug("cannot load unallocSpaceTable (part %d)\n",
1122				  p_index);
1123			return PTR_ERR(inode);
1124		}
1125		map->s_uspace.s_table = inode;
1126		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_TABLE;
1127		udf_debug("unallocSpaceTable (part %d) @ %lu\n",
1128			  p_index, map->s_uspace.s_table->i_ino);
1129	}
1130
1131	if (phd->unallocSpaceBitmap.extLength) {
1132		struct udf_bitmap *bitmap = udf_sb_alloc_bitmap(sb, p_index);
1133		if (!bitmap)
1134			return -ENOMEM;
1135		map->s_uspace.s_bitmap = bitmap;
1136		bitmap->s_extPosition = le32_to_cpu(
1137				phd->unallocSpaceBitmap.extPosition);
1138		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_BITMAP;
1139		udf_debug("unallocSpaceBitmap (part %d) @ %u\n",
1140			  p_index, bitmap->s_extPosition);
1141	}
1142
1143	return 0;
1144}
1145
1146static void udf_find_vat_block(struct super_block *sb, int p_index,
1147			       int type1_index, sector_t start_block)
1148{
1149	struct udf_sb_info *sbi = UDF_SB(sb);
1150	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1151	sector_t vat_block;
1152	struct kernel_lb_addr ino;
1153	struct inode *inode;
1154
1155	/*
1156	 * VAT file entry is in the last recorded block. Some broken disks have
1157	 * it a few blocks before so try a bit harder...
1158	 */
1159	ino.partitionReferenceNum = type1_index;
1160	for (vat_block = start_block;
1161	     vat_block >= map->s_partition_root &&
1162	     vat_block >= start_block - 3; vat_block--) {
1163		ino.logicalBlockNum = vat_block - map->s_partition_root;
1164		inode = udf_iget_special(sb, &ino);
1165		if (!IS_ERR(inode)) {
1166			sbi->s_vat_inode = inode;
1167			break;
1168		}
1169	}
1170}
1171
1172static int udf_load_vat(struct super_block *sb, int p_index, int type1_index)
1173{
1174	struct udf_sb_info *sbi = UDF_SB(sb);
1175	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1176	struct buffer_head *bh = NULL;
1177	struct udf_inode_info *vati;
1178	uint32_t pos;
1179	struct virtualAllocationTable20 *vat20;
1180	sector_t blocks = i_size_read(sb->s_bdev->bd_inode) >>
1181			  sb->s_blocksize_bits;
1182
1183	udf_find_vat_block(sb, p_index, type1_index, sbi->s_last_block);
1184	if (!sbi->s_vat_inode &&
1185	    sbi->s_last_block != blocks - 1) {
1186		pr_notice("Failed to read VAT inode from the last recorded block (%lu), retrying with the last block of the device (%lu).\n",
1187			  (unsigned long)sbi->s_last_block,
1188			  (unsigned long)blocks - 1);
1189		udf_find_vat_block(sb, p_index, type1_index, blocks - 1);
1190	}
1191	if (!sbi->s_vat_inode)
1192		return -EIO;
1193
1194	if (map->s_partition_type == UDF_VIRTUAL_MAP15) {
1195		map->s_type_specific.s_virtual.s_start_offset = 0;
1196		map->s_type_specific.s_virtual.s_num_entries =
1197			(sbi->s_vat_inode->i_size - 36) >> 2;
1198	} else if (map->s_partition_type == UDF_VIRTUAL_MAP20) {
1199		vati = UDF_I(sbi->s_vat_inode);
1200		if (vati->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1201			pos = udf_block_map(sbi->s_vat_inode, 0);
1202			bh = sb_bread(sb, pos);
1203			if (!bh)
1204				return -EIO;
1205			vat20 = (struct virtualAllocationTable20 *)bh->b_data;
1206		} else {
1207			vat20 = (struct virtualAllocationTable20 *)
1208							vati->i_data;
1209		}
1210
1211		map->s_type_specific.s_virtual.s_start_offset =
1212			le16_to_cpu(vat20->lengthHeader);
1213		map->s_type_specific.s_virtual.s_num_entries =
1214			(sbi->s_vat_inode->i_size -
1215				map->s_type_specific.s_virtual.
1216					s_start_offset) >> 2;
1217		brelse(bh);
1218	}
1219	return 0;
1220}
1221
1222/*
1223 * Load partition descriptor block
1224 *
1225 * Returns <0 on error, 0 on success, -EAGAIN is special - try next descriptor
1226 * sequence.
1227 */
1228static int udf_load_partdesc(struct super_block *sb, sector_t block)
1229{
1230	struct buffer_head *bh;
1231	struct partitionDesc *p;
1232	struct udf_part_map *map;
1233	struct udf_sb_info *sbi = UDF_SB(sb);
1234	int i, type1_idx;
1235	uint16_t partitionNumber;
1236	uint16_t ident;
1237	int ret;
1238
1239	bh = udf_read_tagged(sb, block, block, &ident);
1240	if (!bh)
1241		return -EAGAIN;
1242	if (ident != TAG_IDENT_PD) {
1243		ret = 0;
1244		goto out_bh;
1245	}
1246
1247	p = (struct partitionDesc *)bh->b_data;
1248	partitionNumber = le16_to_cpu(p->partitionNumber);
1249
1250	/* First scan for TYPE1 and SPARABLE partitions */
1251	for (i = 0; i < sbi->s_partitions; i++) {
1252		map = &sbi->s_partmaps[i];
1253		udf_debug("Searching map: (%u == %u)\n",
1254			  map->s_partition_num, partitionNumber);
1255		if (map->s_partition_num == partitionNumber &&
1256		    (map->s_partition_type == UDF_TYPE1_MAP15 ||
1257		     map->s_partition_type == UDF_SPARABLE_MAP15))
1258			break;
1259	}
1260
1261	if (i >= sbi->s_partitions) {
1262		udf_debug("Partition (%u) not found in partition map\n",
1263			  partitionNumber);
1264		ret = 0;
1265		goto out_bh;
1266	}
1267
1268	ret = udf_fill_partdesc_info(sb, p, i);
1269	if (ret < 0)
1270		goto out_bh;
1271
1272	/*
1273	 * Now rescan for VIRTUAL or METADATA partitions when SPARABLE and
1274	 * PHYSICAL partitions are already set up
1275	 */
1276	type1_idx = i;
1277	map = NULL; /* supress 'maybe used uninitialized' warning */
1278	for (i = 0; i < sbi->s_partitions; i++) {
1279		map = &sbi->s_partmaps[i];
1280
1281		if (map->s_partition_num == partitionNumber &&
1282		    (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1283		     map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1284		     map->s_partition_type == UDF_METADATA_MAP25))
1285			break;
1286	}
1287
1288	if (i >= sbi->s_partitions) {
1289		ret = 0;
1290		goto out_bh;
1291	}
1292
1293	ret = udf_fill_partdesc_info(sb, p, i);
1294	if (ret < 0)
1295		goto out_bh;
1296
1297	if (map->s_partition_type == UDF_METADATA_MAP25) {
1298		ret = udf_load_metadata_files(sb, i, type1_idx);
1299		if (ret < 0) {
1300			udf_err(sb, "error loading MetaData partition map %d\n",
1301				i);
1302			goto out_bh;
1303		}
1304	} else {
1305		/*
1306		 * If we have a partition with virtual map, we don't handle
1307		 * writing to it (we overwrite blocks instead of relocating
1308		 * them).
1309		 */
1310		if (!sb_rdonly(sb)) {
1311			ret = -EACCES;
1312			goto out_bh;
1313		}
1314		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1315		ret = udf_load_vat(sb, i, type1_idx);
1316		if (ret < 0)
1317			goto out_bh;
1318	}
1319	ret = 0;
1320out_bh:
1321	/* In case loading failed, we handle cleanup in udf_fill_super */
1322	brelse(bh);
1323	return ret;
1324}
1325
1326static int udf_load_sparable_map(struct super_block *sb,
1327				 struct udf_part_map *map,
1328				 struct sparablePartitionMap *spm)
1329{
1330	uint32_t loc;
1331	uint16_t ident;
1332	struct sparingTable *st;
1333	struct udf_sparing_data *sdata = &map->s_type_specific.s_sparing;
1334	int i;
1335	struct buffer_head *bh;
1336
1337	map->s_partition_type = UDF_SPARABLE_MAP15;
1338	sdata->s_packet_len = le16_to_cpu(spm->packetLength);
1339	if (!is_power_of_2(sdata->s_packet_len)) {
1340		udf_err(sb, "error loading logical volume descriptor: "
1341			"Invalid packet length %u\n",
1342			(unsigned)sdata->s_packet_len);
1343		return -EIO;
1344	}
1345	if (spm->numSparingTables > 4) {
1346		udf_err(sb, "error loading logical volume descriptor: "
1347			"Too many sparing tables (%d)\n",
1348			(int)spm->numSparingTables);
1349		return -EIO;
1350	}
1351	if (le32_to_cpu(spm->sizeSparingTable) > sb->s_blocksize) {
1352		udf_err(sb, "error loading logical volume descriptor: "
1353			"Too big sparing table size (%u)\n",
1354			le32_to_cpu(spm->sizeSparingTable));
1355		return -EIO;
1356	}
1357
1358	for (i = 0; i < spm->numSparingTables; i++) {
1359		loc = le32_to_cpu(spm->locSparingTable[i]);
1360		bh = udf_read_tagged(sb, loc, loc, &ident);
1361		if (!bh)
1362			continue;
1363
1364		st = (struct sparingTable *)bh->b_data;
1365		if (ident != 0 ||
1366		    strncmp(st->sparingIdent.ident, UDF_ID_SPARING,
1367			    strlen(UDF_ID_SPARING)) ||
1368		    sizeof(*st) + le16_to_cpu(st->reallocationTableLen) >
1369							sb->s_blocksize) {
1370			brelse(bh);
1371			continue;
1372		}
1373
1374		sdata->s_spar_map[i] = bh;
1375	}
1376	map->s_partition_func = udf_get_pblock_spar15;
1377	return 0;
1378}
1379
1380static int udf_load_logicalvol(struct super_block *sb, sector_t block,
1381			       struct kernel_lb_addr *fileset)
1382{
1383	struct logicalVolDesc *lvd;
1384	int i, offset;
1385	uint8_t type;
1386	struct udf_sb_info *sbi = UDF_SB(sb);
1387	struct genericPartitionMap *gpm;
1388	uint16_t ident;
1389	struct buffer_head *bh;
1390	unsigned int table_len;
1391	int ret;
1392
1393	bh = udf_read_tagged(sb, block, block, &ident);
1394	if (!bh)
1395		return -EAGAIN;
1396	BUG_ON(ident != TAG_IDENT_LVD);
1397	lvd = (struct logicalVolDesc *)bh->b_data;
1398	table_len = le32_to_cpu(lvd->mapTableLength);
1399	if (table_len > sb->s_blocksize - sizeof(*lvd)) {
1400		udf_err(sb, "error loading logical volume descriptor: "
1401			"Partition table too long (%u > %lu)\n", table_len,
1402			sb->s_blocksize - sizeof(*lvd));
1403		ret = -EIO;
1404		goto out_bh;
1405	}
1406
1407	ret = udf_verify_domain_identifier(sb, &lvd->domainIdent,
1408					   "logical volume");
1409	if (ret)
1410		goto out_bh;
1411	ret = udf_sb_alloc_partition_maps(sb, le32_to_cpu(lvd->numPartitionMaps));
1412	if (ret)
1413		goto out_bh;
1414
1415	for (i = 0, offset = 0;
1416	     i < sbi->s_partitions && offset < table_len;
1417	     i++, offset += gpm->partitionMapLength) {
1418		struct udf_part_map *map = &sbi->s_partmaps[i];
1419		gpm = (struct genericPartitionMap *)
1420				&(lvd->partitionMaps[offset]);
1421		type = gpm->partitionMapType;
1422		if (type == 1) {
1423			struct genericPartitionMap1 *gpm1 =
1424				(struct genericPartitionMap1 *)gpm;
1425			map->s_partition_type = UDF_TYPE1_MAP15;
1426			map->s_volumeseqnum = le16_to_cpu(gpm1->volSeqNum);
1427			map->s_partition_num = le16_to_cpu(gpm1->partitionNum);
1428			map->s_partition_func = NULL;
1429		} else if (type == 2) {
1430			struct udfPartitionMap2 *upm2 =
1431						(struct udfPartitionMap2 *)gpm;
1432			if (!strncmp(upm2->partIdent.ident, UDF_ID_VIRTUAL,
1433						strlen(UDF_ID_VIRTUAL))) {
1434				u16 suf =
1435					le16_to_cpu(((__le16 *)upm2->partIdent.
1436							identSuffix)[0]);
1437				if (suf < 0x0200) {
1438					map->s_partition_type =
1439							UDF_VIRTUAL_MAP15;
1440					map->s_partition_func =
1441							udf_get_pblock_virt15;
1442				} else {
1443					map->s_partition_type =
1444							UDF_VIRTUAL_MAP20;
1445					map->s_partition_func =
1446							udf_get_pblock_virt20;
1447				}
1448			} else if (!strncmp(upm2->partIdent.ident,
1449						UDF_ID_SPARABLE,
1450						strlen(UDF_ID_SPARABLE))) {
1451				ret = udf_load_sparable_map(sb, map,
1452					(struct sparablePartitionMap *)gpm);
1453				if (ret < 0)
1454					goto out_bh;
1455			} else if (!strncmp(upm2->partIdent.ident,
1456						UDF_ID_METADATA,
1457						strlen(UDF_ID_METADATA))) {
1458				struct udf_meta_data *mdata =
1459					&map->s_type_specific.s_metadata;
1460				struct metadataPartitionMap *mdm =
1461						(struct metadataPartitionMap *)
1462						&(lvd->partitionMaps[offset]);
1463				udf_debug("Parsing Logical vol part %d type %u  id=%s\n",
1464					  i, type, UDF_ID_METADATA);
1465
1466				map->s_partition_type = UDF_METADATA_MAP25;
1467				map->s_partition_func = udf_get_pblock_meta25;
1468
1469				mdata->s_meta_file_loc   =
1470					le32_to_cpu(mdm->metadataFileLoc);
1471				mdata->s_mirror_file_loc =
1472					le32_to_cpu(mdm->metadataMirrorFileLoc);
1473				mdata->s_bitmap_file_loc =
1474					le32_to_cpu(mdm->metadataBitmapFileLoc);
1475				mdata->s_alloc_unit_size =
1476					le32_to_cpu(mdm->allocUnitSize);
1477				mdata->s_align_unit_size =
1478					le16_to_cpu(mdm->alignUnitSize);
1479				if (mdm->flags & 0x01)
1480					mdata->s_flags |= MF_DUPLICATE_MD;
1481
1482				udf_debug("Metadata Ident suffix=0x%x\n",
1483					  le16_to_cpu(*(__le16 *)
1484						      mdm->partIdent.identSuffix));
1485				udf_debug("Metadata part num=%u\n",
1486					  le16_to_cpu(mdm->partitionNum));
1487				udf_debug("Metadata part alloc unit size=%u\n",
1488					  le32_to_cpu(mdm->allocUnitSize));
1489				udf_debug("Metadata file loc=%u\n",
1490					  le32_to_cpu(mdm->metadataFileLoc));
1491				udf_debug("Mirror file loc=%u\n",
1492					  le32_to_cpu(mdm->metadataMirrorFileLoc));
1493				udf_debug("Bitmap file loc=%u\n",
1494					  le32_to_cpu(mdm->metadataBitmapFileLoc));
1495				udf_debug("Flags: %d %u\n",
1496					  mdata->s_flags, mdm->flags);
1497			} else {
1498				udf_debug("Unknown ident: %s\n",
1499					  upm2->partIdent.ident);
1500				continue;
1501			}
1502			map->s_volumeseqnum = le16_to_cpu(upm2->volSeqNum);
1503			map->s_partition_num = le16_to_cpu(upm2->partitionNum);
1504		}
1505		udf_debug("Partition (%d:%u) type %u on volume %u\n",
1506			  i, map->s_partition_num, type, map->s_volumeseqnum);
1507	}
1508
1509	if (fileset) {
1510		struct long_ad *la = (struct long_ad *)&(lvd->logicalVolContentsUse[0]);
1511
1512		*fileset = lelb_to_cpu(la->extLocation);
1513		udf_debug("FileSet found in LogicalVolDesc at block=%u, partition=%u\n",
1514			  fileset->logicalBlockNum,
1515			  fileset->partitionReferenceNum);
1516	}
1517	if (lvd->integritySeqExt.extLength)
1518		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
1519	ret = 0;
1520
1521	if (!sbi->s_lvid_bh) {
1522		/* We can't generate unique IDs without a valid LVID */
1523		if (sb_rdonly(sb)) {
1524			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1525		} else {
1526			udf_warn(sb, "Damaged or missing LVID, forcing "
1527				     "readonly mount\n");
1528			ret = -EACCES;
1529		}
1530	}
1531out_bh:
1532	brelse(bh);
1533	return ret;
1534}
1535
1536/*
1537 * Find the prevailing Logical Volume Integrity Descriptor.
1538 */
1539static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_ad loc)
1540{
1541	struct buffer_head *bh, *final_bh;
1542	uint16_t ident;
1543	struct udf_sb_info *sbi = UDF_SB(sb);
1544	struct logicalVolIntegrityDesc *lvid;
1545	int indirections = 0;
1546	u32 parts, impuselen;
1547
1548	while (++indirections <= UDF_MAX_LVID_NESTING) {
1549		final_bh = NULL;
1550		while (loc.extLength > 0 &&
1551			(bh = udf_read_tagged(sb, loc.extLocation,
1552					loc.extLocation, &ident))) {
1553			if (ident != TAG_IDENT_LVID) {
1554				brelse(bh);
1555				break;
1556			}
1557
1558			brelse(final_bh);
1559			final_bh = bh;
1560
1561			loc.extLength -= sb->s_blocksize;
1562			loc.extLocation++;
1563		}
1564
1565		if (!final_bh)
1566			return;
1567
1568		brelse(sbi->s_lvid_bh);
1569		sbi->s_lvid_bh = final_bh;
1570
1571		lvid = (struct logicalVolIntegrityDesc *)final_bh->b_data;
1572		if (lvid->nextIntegrityExt.extLength == 0)
1573			goto check;
1574
1575		loc = leea_to_cpu(lvid->nextIntegrityExt);
1576	}
1577
1578	udf_warn(sb, "Too many LVID indirections (max %u), ignoring.\n",
1579		UDF_MAX_LVID_NESTING);
1580out_err:
1581	brelse(sbi->s_lvid_bh);
1582	sbi->s_lvid_bh = NULL;
1583	return;
1584check:
1585	parts = le32_to_cpu(lvid->numOfPartitions);
1586	impuselen = le32_to_cpu(lvid->lengthOfImpUse);
1587	if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
1588	    sizeof(struct logicalVolIntegrityDesc) + impuselen +
1589	    2 * parts * sizeof(u32) > sb->s_blocksize) {
1590		udf_warn(sb, "Corrupted LVID (parts=%u, impuselen=%u), "
1591			 "ignoring.\n", parts, impuselen);
1592		goto out_err;
1593	}
1594}
1595
1596/*
1597 * Step for reallocation of table of partition descriptor sequence numbers.
1598 * Must be power of 2.
1599 */
1600#define PART_DESC_ALLOC_STEP 32
1601
1602struct part_desc_seq_scan_data {
1603	struct udf_vds_record rec;
1604	u32 partnum;
1605};
1606
1607struct desc_seq_scan_data {
1608	struct udf_vds_record vds[VDS_POS_LENGTH];
1609	unsigned int size_part_descs;
1610	unsigned int num_part_descs;
1611	struct part_desc_seq_scan_data *part_descs_loc;
1612};
1613
1614static struct udf_vds_record *handle_partition_descriptor(
1615				struct buffer_head *bh,
1616				struct desc_seq_scan_data *data)
1617{
1618	struct partitionDesc *desc = (struct partitionDesc *)bh->b_data;
1619	int partnum;
1620	int i;
1621
1622	partnum = le16_to_cpu(desc->partitionNumber);
1623	for (i = 0; i < data->num_part_descs; i++)
1624		if (partnum == data->part_descs_loc[i].partnum)
1625			return &(data->part_descs_loc[i].rec);
1626	if (data->num_part_descs >= data->size_part_descs) {
1627		struct part_desc_seq_scan_data *new_loc;
1628		unsigned int new_size = ALIGN(partnum, PART_DESC_ALLOC_STEP);
1629
1630		new_loc = kcalloc(new_size, sizeof(*new_loc), GFP_KERNEL);
1631		if (!new_loc)
1632			return ERR_PTR(-ENOMEM);
1633		memcpy(new_loc, data->part_descs_loc,
1634		       data->size_part_descs * sizeof(*new_loc));
1635		kfree(data->part_descs_loc);
1636		data->part_descs_loc = new_loc;
1637		data->size_part_descs = new_size;
1638	}
1639	return &(data->part_descs_loc[data->num_part_descs++].rec);
1640}
1641
1642
1643static struct udf_vds_record *get_volume_descriptor_record(uint16_t ident,
1644		struct buffer_head *bh, struct desc_seq_scan_data *data)
1645{
1646	switch (ident) {
1647	case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1648		return &(data->vds[VDS_POS_PRIMARY_VOL_DESC]);
1649	case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1650		return &(data->vds[VDS_POS_IMP_USE_VOL_DESC]);
1651	case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1652		return &(data->vds[VDS_POS_LOGICAL_VOL_DESC]);
1653	case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1654		return &(data->vds[VDS_POS_UNALLOC_SPACE_DESC]);
1655	case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1656		return handle_partition_descriptor(bh, data);
1657	}
1658	return NULL;
1659}
1660
1661/*
1662 * Process a main/reserve volume descriptor sequence.
1663 *   @block		First block of first extent of the sequence.
1664 *   @lastblock		Lastblock of first extent of the sequence.
1665 *   @fileset		There we store extent containing root fileset
1666 *
1667 * Returns <0 on error, 0 on success. -EAGAIN is special - try next descriptor
1668 * sequence
1669 */
1670static noinline int udf_process_sequence(
1671		struct super_block *sb,
1672		sector_t block, sector_t lastblock,
1673		struct kernel_lb_addr *fileset)
1674{
1675	struct buffer_head *bh = NULL;
1676	struct udf_vds_record *curr;
1677	struct generic_desc *gd;
1678	struct volDescPtr *vdp;
1679	bool done = false;
1680	uint32_t vdsn;
1681	uint16_t ident;
1682	int ret;
1683	unsigned int indirections = 0;
1684	struct desc_seq_scan_data data;
1685	unsigned int i;
1686
1687	memset(data.vds, 0, sizeof(struct udf_vds_record) * VDS_POS_LENGTH);
1688	data.size_part_descs = PART_DESC_ALLOC_STEP;
1689	data.num_part_descs = 0;
1690	data.part_descs_loc = kcalloc(data.size_part_descs,
1691				      sizeof(*data.part_descs_loc),
1692				      GFP_KERNEL);
1693	if (!data.part_descs_loc)
1694		return -ENOMEM;
1695
1696	/*
1697	 * Read the main descriptor sequence and find which descriptors
1698	 * are in it.
1699	 */
1700	for (; (!done && block <= lastblock); block++) {
1701		bh = udf_read_tagged(sb, block, block, &ident);
1702		if (!bh)
1703			break;
1704
1705		/* Process each descriptor (ISO 13346 3/8.3-8.4) */
1706		gd = (struct generic_desc *)bh->b_data;
1707		vdsn = le32_to_cpu(gd->volDescSeqNum);
1708		switch (ident) {
1709		case TAG_IDENT_VDP: /* ISO 13346 3/10.3 */
1710			if (++indirections > UDF_MAX_TD_NESTING) {
1711				udf_err(sb, "too many Volume Descriptor "
1712					"Pointers (max %u supported)\n",
1713					UDF_MAX_TD_NESTING);
1714				brelse(bh);
1715				ret = -EIO;
1716				goto out;
1717			}
1718
1719			vdp = (struct volDescPtr *)bh->b_data;
1720			block = le32_to_cpu(vdp->nextVolDescSeqExt.extLocation);
1721			lastblock = le32_to_cpu(
1722				vdp->nextVolDescSeqExt.extLength) >>
1723				sb->s_blocksize_bits;
1724			lastblock += block - 1;
1725			/* For loop is going to increment 'block' again */
1726			block--;
1727			break;
1728		case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1729		case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1730		case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1731		case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1732		case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1733			curr = get_volume_descriptor_record(ident, bh, &data);
1734			if (IS_ERR(curr)) {
1735				brelse(bh);
1736				ret = PTR_ERR(curr);
1737				goto out;
1738			}
1739			/* Descriptor we don't care about? */
1740			if (!curr)
1741				break;
1742			if (vdsn >= curr->volDescSeqNum) {
1743				curr->volDescSeqNum = vdsn;
1744				curr->block = block;
1745			}
1746			break;
1747		case TAG_IDENT_TD: /* ISO 13346 3/10.9 */
1748			done = true;
1749			break;
1750		}
1751		brelse(bh);
1752	}
1753	/*
1754	 * Now read interesting descriptors again and process them
1755	 * in a suitable order
1756	 */
1757	if (!data.vds[VDS_POS_PRIMARY_VOL_DESC].block) {
1758		udf_err(sb, "Primary Volume Descriptor not found!\n");
1759		ret = -EAGAIN;
1760		goto out;
1761	}
1762	ret = udf_load_pvoldesc(sb, data.vds[VDS_POS_PRIMARY_VOL_DESC].block);
1763	if (ret < 0)
1764		goto out;
1765
1766	if (data.vds[VDS_POS_LOGICAL_VOL_DESC].block) {
1767		ret = udf_load_logicalvol(sb,
1768				data.vds[VDS_POS_LOGICAL_VOL_DESC].block,
1769				fileset);
1770		if (ret < 0)
1771			goto out;
1772	}
1773
1774	/* Now handle prevailing Partition Descriptors */
1775	for (i = 0; i < data.num_part_descs; i++) {
1776		ret = udf_load_partdesc(sb, data.part_descs_loc[i].rec.block);
1777		if (ret < 0)
1778			goto out;
1779	}
1780	ret = 0;
1781out:
1782	kfree(data.part_descs_loc);
1783	return ret;
1784}
1785
1786/*
1787 * Load Volume Descriptor Sequence described by anchor in bh
1788 *
1789 * Returns <0 on error, 0 on success
1790 */
1791static int udf_load_sequence(struct super_block *sb, struct buffer_head *bh,
1792			     struct kernel_lb_addr *fileset)
1793{
1794	struct anchorVolDescPtr *anchor;
1795	sector_t main_s, main_e, reserve_s, reserve_e;
1796	int ret;
1797
1798	anchor = (struct anchorVolDescPtr *)bh->b_data;
1799
1800	/* Locate the main sequence */
1801	main_s = le32_to_cpu(anchor->mainVolDescSeqExt.extLocation);
1802	main_e = le32_to_cpu(anchor->mainVolDescSeqExt.extLength);
1803	main_e = main_e >> sb->s_blocksize_bits;
1804	main_e += main_s - 1;
1805
1806	/* Locate the reserve sequence */
1807	reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
1808	reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
1809	reserve_e = reserve_e >> sb->s_blocksize_bits;
1810	reserve_e += reserve_s - 1;
1811
1812	/* Process the main & reserve sequences */
1813	/* responsible for finding the PartitionDesc(s) */
1814	ret = udf_process_sequence(sb, main_s, main_e, fileset);
1815	if (ret != -EAGAIN)
1816		return ret;
1817	udf_sb_free_partitions(sb);
1818	ret = udf_process_sequence(sb, reserve_s, reserve_e, fileset);
1819	if (ret < 0) {
1820		udf_sb_free_partitions(sb);
1821		/* No sequence was OK, return -EIO */
1822		if (ret == -EAGAIN)
1823			ret = -EIO;
1824	}
1825	return ret;
1826}
1827
1828/*
1829 * Check whether there is an anchor block in the given block and
1830 * load Volume Descriptor Sequence if so.
1831 *
1832 * Returns <0 on error, 0 on success, -EAGAIN is special - try next anchor
1833 * block
1834 */
1835static int udf_check_anchor_block(struct super_block *sb, sector_t block,
1836				  struct kernel_lb_addr *fileset)
1837{
1838	struct buffer_head *bh;
1839	uint16_t ident;
1840	int ret;
1841
1842	if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV) &&
1843	    udf_fixed_to_variable(block) >=
1844	    i_size_read(sb->s_bdev->bd_inode) >> sb->s_blocksize_bits)
1845		return -EAGAIN;
1846
1847	bh = udf_read_tagged(sb, block, block, &ident);
1848	if (!bh)
1849		return -EAGAIN;
1850	if (ident != TAG_IDENT_AVDP) {
1851		brelse(bh);
1852		return -EAGAIN;
1853	}
1854	ret = udf_load_sequence(sb, bh, fileset);
1855	brelse(bh);
1856	return ret;
1857}
1858
1859/*
1860 * Search for an anchor volume descriptor pointer.
1861 *
1862 * Returns < 0 on error, 0 on success. -EAGAIN is special - try next set
1863 * of anchors.
1864 */
1865static int udf_scan_anchors(struct super_block *sb, sector_t *lastblock,
1866			    struct kernel_lb_addr *fileset)
1867{
1868	sector_t last[6];
1869	int i;
1870	struct udf_sb_info *sbi = UDF_SB(sb);
1871	int last_count = 0;
1872	int ret;
1873
1874	/* First try user provided anchor */
1875	if (sbi->s_anchor) {
1876		ret = udf_check_anchor_block(sb, sbi->s_anchor, fileset);
1877		if (ret != -EAGAIN)
1878			return ret;
1879	}
1880	/*
1881	 * according to spec, anchor is in either:
1882	 *     block 256
1883	 *     lastblock-256
1884	 *     lastblock
1885	 *  however, if the disc isn't closed, it could be 512.
1886	 */
1887	ret = udf_check_anchor_block(sb, sbi->s_session + 256, fileset);
1888	if (ret != -EAGAIN)
1889		return ret;
1890	/*
1891	 * The trouble is which block is the last one. Drives often misreport
1892	 * this so we try various possibilities.
1893	 */
1894	last[last_count++] = *lastblock;
1895	if (*lastblock >= 1)
1896		last[last_count++] = *lastblock - 1;
1897	last[last_count++] = *lastblock + 1;
1898	if (*lastblock >= 2)
1899		last[last_count++] = *lastblock - 2;
1900	if (*lastblock >= 150)
1901		last[last_count++] = *lastblock - 150;
1902	if (*lastblock >= 152)
1903		last[last_count++] = *lastblock - 152;
1904
1905	for (i = 0; i < last_count; i++) {
1906		if (last[i] >= i_size_read(sb->s_bdev->bd_inode) >>
1907				sb->s_blocksize_bits)
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 * Find an anchor volume descriptor and load Volume Descriptor Sequence from
1931 * area specified by it. The function expects sbi->s_lastblock to be the last
1932 * block on the media.
1933 *
1934 * Return <0 on error, 0 if anchor found. -EAGAIN is special meaning anchor
1935 * was not found.
1936 */
1937static int udf_find_anchor(struct super_block *sb,
1938			   struct kernel_lb_addr *fileset)
1939{
1940	struct udf_sb_info *sbi = UDF_SB(sb);
1941	sector_t lastblock = sbi->s_last_block;
1942	int ret;
1943
1944	ret = udf_scan_anchors(sb, &lastblock, fileset);
1945	if (ret != -EAGAIN)
1946		goto out;
1947
1948	/* No anchor found? Try VARCONV conversion of block numbers */
1949	UDF_SET_FLAG(sb, UDF_FLAG_VARCONV);
1950	lastblock = udf_variable_to_fixed(sbi->s_last_block);
1951	/* Firstly, we try to not convert number of the last block */
1952	ret = udf_scan_anchors(sb, &lastblock, fileset);
1953	if (ret != -EAGAIN)
1954		goto out;
1955
1956	lastblock = sbi->s_last_block;
1957	/* Secondly, we try with converted number of the last block */
1958	ret = udf_scan_anchors(sb, &lastblock, fileset);
1959	if (ret < 0) {
1960		/* VARCONV didn't help. Clear it. */
1961		UDF_CLEAR_FLAG(sb, UDF_FLAG_VARCONV);
1962	}
1963out:
1964	if (ret == 0)
1965		sbi->s_last_block = lastblock;
1966	return ret;
1967}
1968
1969/*
1970 * Check Volume Structure Descriptor, find Anchor block and load Volume
1971 * Descriptor Sequence.
1972 *
1973 * Returns < 0 on error, 0 on success. -EAGAIN is special meaning anchor
1974 * block was not found.
1975 */
1976static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
1977			int silent, struct kernel_lb_addr *fileset)
1978{
1979	struct udf_sb_info *sbi = UDF_SB(sb);
1980	int nsr = 0;
1981	int ret;
1982
1983	if (!sb_set_blocksize(sb, uopt->blocksize)) {
1984		if (!silent)
1985			udf_warn(sb, "Bad block size\n");
1986		return -EINVAL;
1987	}
1988	sbi->s_last_block = uopt->lastblock;
1989	if (!uopt->novrs) {
1990		/* Check that it is NSR02 compliant */
1991		nsr = udf_check_vsd(sb);
1992		if (!nsr) {
1993			if (!silent)
1994				udf_warn(sb, "No VRS found\n");
1995			return -EINVAL;
1996		}
1997		if (nsr == -1)
1998			udf_debug("Failed to read sector at offset %d. "
1999				  "Assuming open disc. Skipping validity "
2000				  "check\n", VSD_FIRST_SECTOR_OFFSET);
2001		if (!sbi->s_last_block)
2002			sbi->s_last_block = udf_get_last_block(sb);
2003	} else {
2004		udf_debug("Validity check skipped because of novrs option\n");
2005	}
2006
2007	/* Look for anchor block and load Volume Descriptor Sequence */
2008	sbi->s_anchor = uopt->anchor;
2009	ret = udf_find_anchor(sb, fileset);
2010	if (ret < 0) {
2011		if (!silent && ret == -EAGAIN)
2012			udf_warn(sb, "No anchor found\n");
2013		return ret;
2014	}
2015	return 0;
2016}
2017
2018static void udf_finalize_lvid(struct logicalVolIntegrityDesc *lvid)
2019{
2020	struct timespec64 ts;
2021
2022	ktime_get_real_ts64(&ts);
2023	udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
2024	lvid->descTag.descCRC = cpu_to_le16(
2025		crc_itu_t(0, (char *)lvid + sizeof(struct tag),
2026			le16_to_cpu(lvid->descTag.descCRCLength)));
2027	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
2028}
2029
2030static void udf_open_lvid(struct super_block *sb)
2031{
2032	struct udf_sb_info *sbi = UDF_SB(sb);
2033	struct buffer_head *bh = sbi->s_lvid_bh;
2034	struct logicalVolIntegrityDesc *lvid;
2035	struct logicalVolIntegrityDescImpUse *lvidiu;
2036
2037	if (!bh)
2038		return;
2039	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2040	lvidiu = udf_sb_lvidiu(sb);
2041	if (!lvidiu)
2042		return;
2043
2044	mutex_lock(&sbi->s_alloc_mutex);
2045	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2046	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2047	if (le32_to_cpu(lvid->integrityType) == LVID_INTEGRITY_TYPE_CLOSE)
2048		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
2049	else
2050		UDF_SET_FLAG(sb, UDF_FLAG_INCONSISTENT);
2051
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 opening of filesystem visible on the media immediately */
2057	sync_dirty_buffer(bh);
2058}
2059
2060static void udf_close_lvid(struct super_block *sb)
2061{
2062	struct udf_sb_info *sbi = UDF_SB(sb);
2063	struct buffer_head *bh = sbi->s_lvid_bh;
2064	struct logicalVolIntegrityDesc *lvid;
2065	struct logicalVolIntegrityDescImpUse *lvidiu;
2066
2067	if (!bh)
2068		return;
2069	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2070	lvidiu = udf_sb_lvidiu(sb);
2071	if (!lvidiu)
2072		return;
2073
2074	mutex_lock(&sbi->s_alloc_mutex);
2075	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2076	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2077	if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
2078		lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
2079	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
2080		lvidiu->minUDFReadRev = cpu_to_le16(sbi->s_udfrev);
2081	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFWriteRev))
2082		lvidiu->minUDFWriteRev = cpu_to_le16(sbi->s_udfrev);
2083	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_INCONSISTENT))
2084		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);
2085
2086	/*
2087	 * We set buffer uptodate unconditionally here to avoid spurious
2088	 * warnings from mark_buffer_dirty() when previous EIO has marked
2089	 * the buffer as !uptodate
2090	 */
2091	set_buffer_uptodate(bh);
2092	udf_finalize_lvid(lvid);
2093	mark_buffer_dirty(bh);
2094	sbi->s_lvid_dirty = 0;
2095	mutex_unlock(&sbi->s_alloc_mutex);
2096	/* Make closing of filesystem visible on the media immediately */
2097	sync_dirty_buffer(bh);
2098}
2099
2100u64 lvid_get_unique_id(struct super_block *sb)
2101{
2102	struct buffer_head *bh;
2103	struct udf_sb_info *sbi = UDF_SB(sb);
2104	struct logicalVolIntegrityDesc *lvid;
2105	struct logicalVolHeaderDesc *lvhd;
2106	u64 uniqueID;
2107	u64 ret;
2108
2109	bh = sbi->s_lvid_bh;
2110	if (!bh)
2111		return 0;
2112
2113	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2114	lvhd = (struct logicalVolHeaderDesc *)lvid->logicalVolContentsUse;
2115
2116	mutex_lock(&sbi->s_alloc_mutex);
2117	ret = uniqueID = le64_to_cpu(lvhd->uniqueID);
2118	if (!(++uniqueID & 0xFFFFFFFF))
2119		uniqueID += 16;
2120	lvhd->uniqueID = cpu_to_le64(uniqueID);
2121	udf_updated_lvid(sb);
2122	mutex_unlock(&sbi->s_alloc_mutex);
2123
2124	return ret;
2125}
2126
2127static int udf_fill_super(struct super_block *sb, void *options, int silent)
2128{
2129	int ret = -EINVAL;
2130	struct inode *inode = NULL;
2131	struct udf_options uopt;
2132	struct kernel_lb_addr rootdir, fileset;
2133	struct udf_sb_info *sbi;
2134	bool lvid_open = false;
2135
2136	uopt.flags = (1 << UDF_FLAG_USE_AD_IN_ICB) | (1 << UDF_FLAG_STRICT);
2137	/* By default we'll use overflow[ug]id when UDF inode [ug]id == -1 */
2138	uopt.uid = make_kuid(current_user_ns(), overflowuid);
2139	uopt.gid = make_kgid(current_user_ns(), overflowgid);
2140	uopt.umask = 0;
2141	uopt.fmode = UDF_INVALID_MODE;
2142	uopt.dmode = UDF_INVALID_MODE;
2143	uopt.nls_map = NULL;
2144
2145	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2146	if (!sbi)
2147		return -ENOMEM;
2148
2149	sb->s_fs_info = sbi;
2150
2151	mutex_init(&sbi->s_alloc_mutex);
2152
2153	if (!udf_parse_options((char *)options, &uopt, false))
2154		goto parse_options_failure;
2155
2156	fileset.logicalBlockNum = 0xFFFFFFFF;
2157	fileset.partitionReferenceNum = 0xFFFF;
2158
2159	sbi->s_flags = uopt.flags;
2160	sbi->s_uid = uopt.uid;
2161	sbi->s_gid = uopt.gid;
2162	sbi->s_umask = uopt.umask;
2163	sbi->s_fmode = uopt.fmode;
2164	sbi->s_dmode = uopt.dmode;
2165	sbi->s_nls_map = uopt.nls_map;
2166	rwlock_init(&sbi->s_cred_lock);
2167
2168	if (uopt.session == 0xFFFFFFFF)
2169		sbi->s_session = udf_get_last_session(sb);
2170	else
2171		sbi->s_session = uopt.session;
2172
2173	udf_debug("Multi-session=%d\n", sbi->s_session);
2174
2175	/* Fill in the rest of the superblock */
2176	sb->s_op = &udf_sb_ops;
2177	sb->s_export_op = &udf_export_ops;
2178
2179	sb->s_magic = UDF_SUPER_MAGIC;
2180	sb->s_time_gran = 1000;
2181
2182	if (uopt.flags & (1 << UDF_FLAG_BLOCKSIZE_SET)) {
2183		ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2184	} else {
2185		uopt.blocksize = bdev_logical_block_size(sb->s_bdev);
2186		while (uopt.blocksize <= 4096) {
2187			ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2188			if (ret < 0) {
2189				if (!silent && ret != -EACCES) {
2190					pr_notice("Scanning with blocksize %u failed\n",
2191						  uopt.blocksize);
2192				}
2193				brelse(sbi->s_lvid_bh);
2194				sbi->s_lvid_bh = NULL;
2195				/*
2196				 * EACCES is special - we want to propagate to
2197				 * upper layers that we cannot handle RW mount.
2198				 */
2199				if (ret == -EACCES)
2200					break;
2201			} else
2202				break;
2203
2204			uopt.blocksize <<= 1;
2205		}
2206	}
2207	if (ret < 0) {
2208		if (ret == -EAGAIN) {
2209			udf_warn(sb, "No partition found (1)\n");
2210			ret = -EINVAL;
2211		}
2212		goto error_out;
2213	}
2214
2215	udf_debug("Lastblock=%u\n", sbi->s_last_block);
2216
2217	if (sbi->s_lvid_bh) {
2218		struct logicalVolIntegrityDescImpUse *lvidiu =
2219							udf_sb_lvidiu(sb);
2220		uint16_t minUDFReadRev;
2221		uint16_t minUDFWriteRev;
2222
2223		if (!lvidiu) {
2224			ret = -EINVAL;
2225			goto error_out;
2226		}
2227		minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev);
2228		minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev);
2229		if (minUDFReadRev > UDF_MAX_READ_VERSION) {
2230			udf_err(sb, "minUDFReadRev=%x (max is %x)\n",
2231				minUDFReadRev,
2232				UDF_MAX_READ_VERSION);
2233			ret = -EINVAL;
2234			goto error_out;
2235		} else if (minUDFWriteRev > UDF_MAX_WRITE_VERSION) {
2236			if (!sb_rdonly(sb)) {
2237				ret = -EACCES;
2238				goto error_out;
2239			}
2240			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2241		}
2242
2243		sbi->s_udfrev = minUDFWriteRev;
2244
2245		if (minUDFReadRev >= UDF_VERS_USE_EXTENDED_FE)
2246			UDF_SET_FLAG(sb, UDF_FLAG_USE_EXTENDED_FE);
2247		if (minUDFReadRev >= UDF_VERS_USE_STREAMS)
2248			UDF_SET_FLAG(sb, UDF_FLAG_USE_STREAMS);
2249	}
2250
2251	if (!sbi->s_partitions) {
2252		udf_warn(sb, "No partition found (2)\n");
2253		ret = -EINVAL;
2254		goto error_out;
2255	}
2256
2257	if (sbi->s_partmaps[sbi->s_partition].s_partition_flags &
2258			UDF_PART_FLAG_READ_ONLY) {
2259		if (!sb_rdonly(sb)) {
2260			ret = -EACCES;
2261			goto error_out;
2262		}
2263		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2264	}
2265
2266	ret = udf_find_fileset(sb, &fileset, &rootdir);
2267	if (ret < 0) {
2268		udf_warn(sb, "No fileset found\n");
2269		goto error_out;
2270	}
2271
2272	if (!silent) {
2273		struct timestamp ts;
2274		udf_time_to_disk_stamp(&ts, sbi->s_record_time);
2275		udf_info("Mounting volume '%s', timestamp %04u/%02u/%02u %02u:%02u (%x)\n",
2276			 sbi->s_volume_ident,
2277			 le16_to_cpu(ts.year), ts.month, ts.day,
2278			 ts.hour, ts.minute, le16_to_cpu(ts.typeAndTimezone));
2279	}
2280	if (!sb_rdonly(sb)) {
2281		udf_open_lvid(sb);
2282		lvid_open = true;
2283	}
2284
2285	/* Assign the root inode */
2286	/* assign inodes by physical block number */
2287	/* perhaps it's not extensible enough, but for now ... */
2288	inode = udf_iget(sb, &rootdir);
2289	if (IS_ERR(inode)) {
2290		udf_err(sb, "Error in udf_iget, block=%u, partition=%u\n",
2291		       rootdir.logicalBlockNum, rootdir.partitionReferenceNum);
2292		ret = PTR_ERR(inode);
2293		goto error_out;
2294	}
2295
2296	/* Allocate a dentry for the root inode */
2297	sb->s_root = d_make_root(inode);
2298	if (!sb->s_root) {
2299		udf_err(sb, "Couldn't allocate root dentry\n");
2300		ret = -ENOMEM;
2301		goto error_out;
2302	}
2303	sb->s_maxbytes = MAX_LFS_FILESIZE;
2304	sb->s_max_links = UDF_MAX_LINKS;
2305	return 0;
2306
2307error_out:
2308	iput(sbi->s_vat_inode);
2309parse_options_failure:
2310	unload_nls(uopt.nls_map);
2311	if (lvid_open)
2312		udf_close_lvid(sb);
2313	brelse(sbi->s_lvid_bh);
2314	udf_sb_free_partitions(sb);
2315	kfree(sbi);
2316	sb->s_fs_info = NULL;
2317
2318	return ret;
2319}
2320
2321void _udf_err(struct super_block *sb, const char *function,
2322	      const char *fmt, ...)
2323{
2324	struct va_format vaf;
2325	va_list args;
2326
2327	va_start(args, fmt);
2328
2329	vaf.fmt = fmt;
2330	vaf.va = &args;
2331
2332	pr_err("error (device %s): %s: %pV", sb->s_id, function, &vaf);
2333
2334	va_end(args);
2335}
2336
2337void _udf_warn(struct super_block *sb, const char *function,
2338	       const char *fmt, ...)
2339{
2340	struct va_format vaf;
2341	va_list args;
2342
2343	va_start(args, fmt);
2344
2345	vaf.fmt = fmt;
2346	vaf.va = &args;
2347
2348	pr_warn("warning (device %s): %s: %pV", sb->s_id, function, &vaf);
2349
2350	va_end(args);
2351}
2352
2353static void udf_put_super(struct super_block *sb)
2354{
2355	struct udf_sb_info *sbi;
2356
2357	sbi = UDF_SB(sb);
2358
2359	iput(sbi->s_vat_inode);
2360	unload_nls(sbi->s_nls_map);
2361	if (!sb_rdonly(sb))
2362		udf_close_lvid(sb);
2363	brelse(sbi->s_lvid_bh);
2364	udf_sb_free_partitions(sb);
2365	mutex_destroy(&sbi->s_alloc_mutex);
2366	kfree(sb->s_fs_info);
2367	sb->s_fs_info = NULL;
2368}
2369
2370static int udf_sync_fs(struct super_block *sb, int wait)
2371{
2372	struct udf_sb_info *sbi = UDF_SB(sb);
2373
2374	mutex_lock(&sbi->s_alloc_mutex);
2375	if (sbi->s_lvid_dirty) {
2376		struct buffer_head *bh = sbi->s_lvid_bh;
2377		struct logicalVolIntegrityDesc *lvid;
2378
2379		lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2380		udf_finalize_lvid(lvid);
2381
2382		/*
2383		 * Blockdevice will be synced later so we don't have to submit
2384		 * the buffer for IO
2385		 */
2386		mark_buffer_dirty(bh);
2387		sbi->s_lvid_dirty = 0;
2388	}
2389	mutex_unlock(&sbi->s_alloc_mutex);
2390
2391	return 0;
2392}
2393
2394static int udf_statfs(struct dentry *dentry, struct kstatfs *buf)
2395{
2396	struct super_block *sb = dentry->d_sb;
2397	struct udf_sb_info *sbi = UDF_SB(sb);
2398	struct logicalVolIntegrityDescImpUse *lvidiu;
2399	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
2400
2401	lvidiu = udf_sb_lvidiu(sb);
2402	buf->f_type = UDF_SUPER_MAGIC;
2403	buf->f_bsize = sb->s_blocksize;
2404	buf->f_blocks = sbi->s_partmaps[sbi->s_partition].s_partition_len;
2405	buf->f_bfree = udf_count_free(sb);
2406	buf->f_bavail = buf->f_bfree;
2407	/*
2408	 * Let's pretend each free block is also a free 'inode' since UDF does
2409	 * not have separate preallocated table of inodes.
2410	 */
2411	buf->f_files = (lvidiu != NULL ? (le32_to_cpu(lvidiu->numFiles) +
2412					  le32_to_cpu(lvidiu->numDirs)) : 0)
2413			+ buf->f_bfree;
2414	buf->f_ffree = buf->f_bfree;
2415	buf->f_namelen = UDF_NAME_LEN;
2416	buf->f_fsid = u64_to_fsid(id);
2417
2418	return 0;
2419}
2420
2421static unsigned int udf_count_free_bitmap(struct super_block *sb,
2422					  struct udf_bitmap *bitmap)
2423{
2424	struct buffer_head *bh = NULL;
2425	unsigned int accum = 0;
2426	int index;
2427	udf_pblk_t block = 0, newblock;
2428	struct kernel_lb_addr loc;
2429	uint32_t bytes;
2430	uint8_t *ptr;
2431	uint16_t ident;
2432	struct spaceBitmapDesc *bm;
2433
2434	loc.logicalBlockNum = bitmap->s_extPosition;
2435	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
2436	bh = udf_read_ptagged(sb, &loc, 0, &ident);
2437
2438	if (!bh) {
2439		udf_err(sb, "udf_count_free failed\n");
2440		goto out;
2441	} else if (ident != TAG_IDENT_SBD) {
2442		brelse(bh);
2443		udf_err(sb, "udf_count_free failed\n");
2444		goto out;
2445	}
2446
2447	bm = (struct spaceBitmapDesc *)bh->b_data;
2448	bytes = le32_to_cpu(bm->numOfBytes);
2449	index = sizeof(struct spaceBitmapDesc); /* offset in first block only */
2450	ptr = (uint8_t *)bh->b_data;
2451
2452	while (bytes > 0) {
2453		u32 cur_bytes = min_t(u32, bytes, sb->s_blocksize - index);
2454		accum += bitmap_weight((const unsigned long *)(ptr + index),
2455					cur_bytes * 8);
2456		bytes -= cur_bytes;
2457		if (bytes) {
2458			brelse(bh);
2459			newblock = udf_get_lb_pblock(sb, &loc, ++block);
2460			bh = udf_tread(sb, newblock);
2461			if (!bh) {
2462				udf_debug("read failed\n");
2463				goto out;
2464			}
2465			index = 0;
2466			ptr = (uint8_t *)bh->b_data;
2467		}
2468	}
2469	brelse(bh);
2470out:
2471	return accum;
2472}
2473
2474static unsigned int udf_count_free_table(struct super_block *sb,
2475					 struct inode *table)
2476{
2477	unsigned int accum = 0;
2478	uint32_t elen;
2479	struct kernel_lb_addr eloc;
2480	int8_t etype;
2481	struct extent_position epos;
2482
2483	mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
2484	epos.block = UDF_I(table)->i_location;
2485	epos.offset = sizeof(struct unallocSpaceEntry);
2486	epos.bh = NULL;
2487
2488	while ((etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1)
2489		accum += (elen >> table->i_sb->s_blocksize_bits);
2490
2491	brelse(epos.bh);
2492	mutex_unlock(&UDF_SB(sb)->s_alloc_mutex);
2493
2494	return accum;
2495}
2496
2497static unsigned int udf_count_free(struct super_block *sb)
2498{
2499	unsigned int accum = 0;
2500	struct udf_sb_info *sbi = UDF_SB(sb);
2501	struct udf_part_map *map;
2502	unsigned int part = sbi->s_partition;
2503	int ptype = sbi->s_partmaps[part].s_partition_type;
2504
2505	if (ptype == UDF_METADATA_MAP25) {
2506		part = sbi->s_partmaps[part].s_type_specific.s_metadata.
2507							s_phys_partition_ref;
2508	} else if (ptype == UDF_VIRTUAL_MAP15 || ptype == UDF_VIRTUAL_MAP20) {
2509		/*
2510		 * Filesystems with VAT are append-only and we cannot write to
2511 		 * them. Let's just report 0 here.
2512		 */
2513		return 0;
2514	}
2515
2516	if (sbi->s_lvid_bh) {
2517		struct logicalVolIntegrityDesc *lvid =
2518			(struct logicalVolIntegrityDesc *)
2519			sbi->s_lvid_bh->b_data;
2520		if (le32_to_cpu(lvid->numOfPartitions) > part) {
2521			accum = le32_to_cpu(
2522					lvid->freeSpaceTable[part]);
2523			if (accum == 0xFFFFFFFF)
2524				accum = 0;
2525		}
2526	}
2527
2528	if (accum)
2529		return accum;
2530
2531	map = &sbi->s_partmaps[part];
2532	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
2533		accum += udf_count_free_bitmap(sb,
2534					       map->s_uspace.s_bitmap);
2535	}
2536	if (accum)
2537		return accum;
2538
2539	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
2540		accum += udf_count_free_table(sb,
2541					      map->s_uspace.s_table);
2542	}
2543	return accum;
2544}
2545
2546MODULE_AUTHOR("Ben Fennema");
2547MODULE_DESCRIPTION("Universal Disk Format Filesystem");
2548MODULE_LICENSE("GPL");
2549module_init(init_udf_fs)
2550module_exit(exit_udf_fs)
2551