xref: /linux/fs/udf/super.c (revision b7019ac550eb3916f34d79db583e9b7ea2524afa)
1 /*
2  * super.c
3  *
4  * PURPOSE
5  *  Super block routines for the OSTA-UDF(tm) filesystem.
6  *
7  * DESCRIPTION
8  *  OSTA-UDF(tm) = Optical Storage Technology Association
9  *  Universal Disk Format.
10  *
11  *  This code is based on version 2.00 of the UDF specification,
12  *  and revision 3 of the ECMA 167 standard [equivalent to ISO 13346].
13  *    http://www.osta.org/
14  *    http://www.ecma.ch/
15  *    http://www.iso.org/
16  *
17  * COPYRIGHT
18  *  This file is distributed under the terms of the GNU General Public
19  *  License (GPL). Copies of the GPL can be obtained from:
20  *    ftp://prep.ai.mit.edu/pub/gnu/GPL
21  *  Each contributing author retains all rights to their own work.
22  *
23  *  (C) 1998 Dave Boynton
24  *  (C) 1998-2004 Ben Fennema
25  *  (C) 2000 Stelias Computing Inc
26  *
27  * HISTORY
28  *
29  *  09/24/98 dgb  changed to allow compiling outside of kernel, and
30  *                added some debugging.
31  *  10/01/98 dgb  updated to allow (some) possibility of compiling w/2.0.34
32  *  10/16/98      attempting some multi-session support
33  *  10/17/98      added freespace count for "df"
34  *  11/11/98 gr   added novrs option
35  *  11/26/98 dgb  added fileset,anchor mount options
36  *  12/06/98 blf  really hosed things royally. vat/sparing support. sequenced
37  *                vol descs. rewrote option handling based on isofs
38  *  12/20/98      find the free space bitmap (if it exists)
39  */
40 
41 #include "udfdecl.h"
42 
43 #include <linux/blkdev.h>
44 #include <linux/slab.h>
45 #include <linux/kernel.h>
46 #include <linux/module.h>
47 #include <linux/parser.h>
48 #include <linux/stat.h>
49 #include <linux/cdrom.h>
50 #include <linux/nls.h>
51 #include <linux/vfs.h>
52 #include <linux/vmalloc.h>
53 #include <linux/errno.h>
54 #include <linux/mount.h>
55 #include <linux/seq_file.h>
56 #include <linux/bitmap.h>
57 #include <linux/crc-itu-t.h>
58 #include <linux/log2.h>
59 #include <asm/byteorder.h>
60 
61 #include "udf_sb.h"
62 #include "udf_i.h"
63 
64 #include <linux/init.h>
65 #include <linux/uaccess.h>
66 
67 enum {
68 	VDS_POS_PRIMARY_VOL_DESC,
69 	VDS_POS_UNALLOC_SPACE_DESC,
70 	VDS_POS_LOGICAL_VOL_DESC,
71 	VDS_POS_IMP_USE_VOL_DESC,
72 	VDS_POS_LENGTH
73 };
74 
75 #define VSD_FIRST_SECTOR_OFFSET		32768
76 #define VSD_MAX_SECTOR_OFFSET		0x800000
77 
78 /*
79  * Maximum number of Terminating Descriptor / Logical Volume Integrity
80  * Descriptor redirections. The chosen numbers are arbitrary - just that we
81  * hopefully don't limit any real use of rewritten inode on write-once media
82  * but avoid looping for too long on corrupted media.
83  */
84 #define UDF_MAX_TD_NESTING 64
85 #define UDF_MAX_LVID_NESTING 1000
86 
87 enum { UDF_MAX_LINKS = 0xffff };
88 
89 /* These are the "meat" - everything else is stuffing */
90 static int udf_fill_super(struct super_block *, void *, int);
91 static void udf_put_super(struct super_block *);
92 static int udf_sync_fs(struct super_block *, int);
93 static int udf_remount_fs(struct super_block *, int *, char *);
94 static void udf_load_logicalvolint(struct super_block *, struct kernel_extent_ad);
95 static int udf_find_fileset(struct super_block *, struct kernel_lb_addr *,
96 			    struct kernel_lb_addr *);
97 static void udf_load_fileset(struct super_block *, struct buffer_head *,
98 			     struct kernel_lb_addr *);
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 	if ((sb->s_blocksize - sizeof(struct logicalVolIntegrityDescImpUse) -
116 	     offsetof(struct logicalVolIntegrityDesc, impUse)) /
117 	     (2 * sizeof(uint32_t)) < partnum) {
118 		udf_err(sb, "Logical volume integrity descriptor corrupted "
119 			"(numOfPartitions = %u)!\n", partnum);
120 		return NULL;
121 	}
122 	/* The offset is to skip freeSpaceTable and sizeTable arrays */
123 	offset = partnum * 2 * sizeof(uint32_t);
124 	return (struct logicalVolIntegrityDescImpUse *)&(lvid->impUse[offset]);
125 }
126 
127 /* UDF filesystem type */
128 static struct dentry *udf_mount(struct file_system_type *fs_type,
129 		      int flags, const char *dev_name, void *data)
130 {
131 	return mount_bdev(fs_type, flags, dev_name, data, udf_fill_super);
132 }
133 
134 static struct file_system_type udf_fstype = {
135 	.owner		= THIS_MODULE,
136 	.name		= "udf",
137 	.mount		= udf_mount,
138 	.kill_sb	= kill_block_super,
139 	.fs_flags	= FS_REQUIRES_DEV,
140 };
141 MODULE_ALIAS_FS("udf");
142 
143 static struct kmem_cache *udf_inode_cachep;
144 
145 static struct inode *udf_alloc_inode(struct super_block *sb)
146 {
147 	struct udf_inode_info *ei;
148 	ei = kmem_cache_alloc(udf_inode_cachep, GFP_KERNEL);
149 	if (!ei)
150 		return NULL;
151 
152 	ei->i_unique = 0;
153 	ei->i_lenExtents = 0;
154 	ei->i_next_alloc_block = 0;
155 	ei->i_next_alloc_goal = 0;
156 	ei->i_strat4096 = 0;
157 	init_rwsem(&ei->i_data_sem);
158 	ei->cached_extent.lstart = -1;
159 	spin_lock_init(&ei->i_extent_cache_lock);
160 
161 	return &ei->vfs_inode;
162 }
163 
164 static void udf_free_in_core_inode(struct inode *inode)
165 {
166 	kmem_cache_free(udf_inode_cachep, UDF_I(inode));
167 }
168 
169 static void init_once(void *foo)
170 {
171 	struct udf_inode_info *ei = (struct udf_inode_info *)foo;
172 
173 	ei->i_ext.i_data = NULL;
174 	inode_init_once(&ei->vfs_inode);
175 }
176 
177 static int __init init_inodecache(void)
178 {
179 	udf_inode_cachep = kmem_cache_create("udf_inode_cache",
180 					     sizeof(struct udf_inode_info),
181 					     0, (SLAB_RECLAIM_ACCOUNT |
182 						 SLAB_MEM_SPREAD |
183 						 SLAB_ACCOUNT),
184 					     init_once);
185 	if (!udf_inode_cachep)
186 		return -ENOMEM;
187 	return 0;
188 }
189 
190 static void destroy_inodecache(void)
191 {
192 	/*
193 	 * Make sure all delayed rcu free inodes are flushed before we
194 	 * destroy cache.
195 	 */
196 	rcu_barrier();
197 	kmem_cache_destroy(udf_inode_cachep);
198 }
199 
200 /* Superblock operations */
201 static const struct super_operations udf_sb_ops = {
202 	.alloc_inode	= udf_alloc_inode,
203 	.free_inode	= udf_free_in_core_inode,
204 	.write_inode	= udf_write_inode,
205 	.evict_inode	= udf_evict_inode,
206 	.put_super	= udf_put_super,
207 	.sync_fs	= udf_sync_fs,
208 	.statfs		= udf_statfs,
209 	.remount_fs	= udf_remount_fs,
210 	.show_options	= udf_show_options,
211 };
212 
213 struct udf_options {
214 	unsigned char novrs;
215 	unsigned int blocksize;
216 	unsigned int session;
217 	unsigned int lastblock;
218 	unsigned int anchor;
219 	unsigned int flags;
220 	umode_t umask;
221 	kgid_t gid;
222 	kuid_t uid;
223 	umode_t fmode;
224 	umode_t dmode;
225 	struct nls_table *nls_map;
226 };
227 
228 static int __init init_udf_fs(void)
229 {
230 	int err;
231 
232 	err = init_inodecache();
233 	if (err)
234 		goto out1;
235 	err = register_filesystem(&udf_fstype);
236 	if (err)
237 		goto out;
238 
239 	return 0;
240 
241 out:
242 	destroy_inodecache();
243 
244 out1:
245 	return err;
246 }
247 
248 static void __exit exit_udf_fs(void)
249 {
250 	unregister_filesystem(&udf_fstype);
251 	destroy_inodecache();
252 }
253 
254 static int udf_sb_alloc_partition_maps(struct super_block *sb, u32 count)
255 {
256 	struct udf_sb_info *sbi = UDF_SB(sb);
257 
258 	sbi->s_partmaps = kcalloc(count, sizeof(*sbi->s_partmaps), GFP_KERNEL);
259 	if (!sbi->s_partmaps) {
260 		sbi->s_partitions = 0;
261 		return -ENOMEM;
262 	}
263 
264 	sbi->s_partitions = count;
265 	return 0;
266 }
267 
268 static void udf_sb_free_bitmap(struct udf_bitmap *bitmap)
269 {
270 	int i;
271 	int nr_groups = bitmap->s_nr_groups;
272 
273 	for (i = 0; i < nr_groups; i++)
274 		if (bitmap->s_block_bitmap[i])
275 			brelse(bitmap->s_block_bitmap[i]);
276 
277 	kvfree(bitmap);
278 }
279 
280 static void udf_free_partition(struct udf_part_map *map)
281 {
282 	int i;
283 	struct udf_meta_data *mdata;
284 
285 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
286 		iput(map->s_uspace.s_table);
287 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
288 		udf_sb_free_bitmap(map->s_uspace.s_bitmap);
289 	if (map->s_partition_type == UDF_SPARABLE_MAP15)
290 		for (i = 0; i < 4; i++)
291 			brelse(map->s_type_specific.s_sparing.s_spar_map[i]);
292 	else if (map->s_partition_type == UDF_METADATA_MAP25) {
293 		mdata = &map->s_type_specific.s_metadata;
294 		iput(mdata->s_metadata_fe);
295 		mdata->s_metadata_fe = NULL;
296 
297 		iput(mdata->s_mirror_fe);
298 		mdata->s_mirror_fe = NULL;
299 
300 		iput(mdata->s_bitmap_fe);
301 		mdata->s_bitmap_fe = NULL;
302 	}
303 }
304 
305 static void udf_sb_free_partitions(struct super_block *sb)
306 {
307 	struct udf_sb_info *sbi = UDF_SB(sb);
308 	int i;
309 
310 	if (!sbi->s_partmaps)
311 		return;
312 	for (i = 0; i < sbi->s_partitions; i++)
313 		udf_free_partition(&sbi->s_partmaps[i]);
314 	kfree(sbi->s_partmaps);
315 	sbi->s_partmaps = NULL;
316 }
317 
318 static int udf_show_options(struct seq_file *seq, struct dentry *root)
319 {
320 	struct super_block *sb = root->d_sb;
321 	struct udf_sb_info *sbi = UDF_SB(sb);
322 
323 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT))
324 		seq_puts(seq, ",nostrict");
325 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_BLOCKSIZE_SET))
326 		seq_printf(seq, ",bs=%lu", sb->s_blocksize);
327 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
328 		seq_puts(seq, ",unhide");
329 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
330 		seq_puts(seq, ",undelete");
331 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_USE_AD_IN_ICB))
332 		seq_puts(seq, ",noadinicb");
333 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_USE_SHORT_AD))
334 		seq_puts(seq, ",shortad");
335 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_FORGET))
336 		seq_puts(seq, ",uid=forget");
337 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_FORGET))
338 		seq_puts(seq, ",gid=forget");
339 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET))
340 		seq_printf(seq, ",uid=%u", from_kuid(&init_user_ns, sbi->s_uid));
341 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET))
342 		seq_printf(seq, ",gid=%u", from_kgid(&init_user_ns, sbi->s_gid));
343 	if (sbi->s_umask != 0)
344 		seq_printf(seq, ",umask=%ho", sbi->s_umask);
345 	if (sbi->s_fmode != UDF_INVALID_MODE)
346 		seq_printf(seq, ",mode=%ho", sbi->s_fmode);
347 	if (sbi->s_dmode != UDF_INVALID_MODE)
348 		seq_printf(seq, ",dmode=%ho", sbi->s_dmode);
349 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_SESSION_SET))
350 		seq_printf(seq, ",session=%d", sbi->s_session);
351 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_LASTBLOCK_SET))
352 		seq_printf(seq, ",lastblock=%u", sbi->s_last_block);
353 	if (sbi->s_anchor != 0)
354 		seq_printf(seq, ",anchor=%u", sbi->s_anchor);
355 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8))
356 		seq_puts(seq, ",utf8");
357 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP) && sbi->s_nls_map)
358 		seq_printf(seq, ",iocharset=%s", sbi->s_nls_map->charset);
359 
360 	return 0;
361 }
362 
363 /*
364  * udf_parse_options
365  *
366  * PURPOSE
367  *	Parse mount options.
368  *
369  * DESCRIPTION
370  *	The following mount options are supported:
371  *
372  *	gid=		Set the default group.
373  *	umask=		Set the default umask.
374  *	mode=		Set the default file permissions.
375  *	dmode=		Set the default directory permissions.
376  *	uid=		Set the default user.
377  *	bs=		Set the block size.
378  *	unhide		Show otherwise hidden files.
379  *	undelete	Show deleted files in lists.
380  *	adinicb		Embed data in the inode (default)
381  *	noadinicb	Don't embed data in the inode
382  *	shortad		Use short ad's
383  *	longad		Use long ad's (default)
384  *	nostrict	Unset strict conformance
385  *	iocharset=	Set the NLS character set
386  *
387  *	The remaining are for debugging and disaster recovery:
388  *
389  *	novrs		Skip volume sequence recognition
390  *
391  *	The following expect a offset from 0.
392  *
393  *	session=	Set the CDROM session (default= last session)
394  *	anchor=		Override standard anchor location. (default= 256)
395  *	volume=		Override the VolumeDesc location. (unused)
396  *	partition=	Override the PartitionDesc location. (unused)
397  *	lastblock=	Set the last block of the filesystem/
398  *
399  *	The following expect a offset from the partition root.
400  *
401  *	fileset=	Override the fileset block location. (unused)
402  *	rootdir=	Override the root directory location. (unused)
403  *		WARNING: overriding the rootdir to a non-directory may
404  *		yield highly unpredictable results.
405  *
406  * PRE-CONDITIONS
407  *	options		Pointer to mount options string.
408  *	uopts		Pointer to mount options variable.
409  *
410  * POST-CONDITIONS
411  *	<return>	1	Mount options parsed okay.
412  *	<return>	0	Error parsing mount options.
413  *
414  * HISTORY
415  *	July 1, 1997 - Andrew E. Mileski
416  *	Written, tested, and released.
417  */
418 
419 enum {
420 	Opt_novrs, Opt_nostrict, Opt_bs, Opt_unhide, Opt_undelete,
421 	Opt_noadinicb, Opt_adinicb, Opt_shortad, Opt_longad,
422 	Opt_gid, Opt_uid, Opt_umask, Opt_session, Opt_lastblock,
423 	Opt_anchor, Opt_volume, Opt_partition, Opt_fileset,
424 	Opt_rootdir, Opt_utf8, Opt_iocharset,
425 	Opt_err, Opt_uforget, Opt_uignore, Opt_gforget, Opt_gignore,
426 	Opt_fmode, Opt_dmode
427 };
428 
429 static const match_table_t tokens = {
430 	{Opt_novrs,	"novrs"},
431 	{Opt_nostrict,	"nostrict"},
432 	{Opt_bs,	"bs=%u"},
433 	{Opt_unhide,	"unhide"},
434 	{Opt_undelete,	"undelete"},
435 	{Opt_noadinicb,	"noadinicb"},
436 	{Opt_adinicb,	"adinicb"},
437 	{Opt_shortad,	"shortad"},
438 	{Opt_longad,	"longad"},
439 	{Opt_uforget,	"uid=forget"},
440 	{Opt_uignore,	"uid=ignore"},
441 	{Opt_gforget,	"gid=forget"},
442 	{Opt_gignore,	"gid=ignore"},
443 	{Opt_gid,	"gid=%u"},
444 	{Opt_uid,	"uid=%u"},
445 	{Opt_umask,	"umask=%o"},
446 	{Opt_session,	"session=%u"},
447 	{Opt_lastblock,	"lastblock=%u"},
448 	{Opt_anchor,	"anchor=%u"},
449 	{Opt_volume,	"volume=%u"},
450 	{Opt_partition,	"partition=%u"},
451 	{Opt_fileset,	"fileset=%u"},
452 	{Opt_rootdir,	"rootdir=%u"},
453 	{Opt_utf8,	"utf8"},
454 	{Opt_iocharset,	"iocharset=%s"},
455 	{Opt_fmode,     "mode=%o"},
456 	{Opt_dmode,     "dmode=%o"},
457 	{Opt_err,	NULL}
458 };
459 
460 static int udf_parse_options(char *options, struct udf_options *uopt,
461 			     bool remount)
462 {
463 	char *p;
464 	int option;
465 
466 	uopt->novrs = 0;
467 	uopt->session = 0xFFFFFFFF;
468 	uopt->lastblock = 0;
469 	uopt->anchor = 0;
470 
471 	if (!options)
472 		return 1;
473 
474 	while ((p = strsep(&options, ",")) != NULL) {
475 		substring_t args[MAX_OPT_ARGS];
476 		int token;
477 		unsigned n;
478 		if (!*p)
479 			continue;
480 
481 		token = match_token(p, tokens, args);
482 		switch (token) {
483 		case Opt_novrs:
484 			uopt->novrs = 1;
485 			break;
486 		case Opt_bs:
487 			if (match_int(&args[0], &option))
488 				return 0;
489 			n = option;
490 			if (n != 512 && n != 1024 && n != 2048 && n != 4096)
491 				return 0;
492 			uopt->blocksize = n;
493 			uopt->flags |= (1 << UDF_FLAG_BLOCKSIZE_SET);
494 			break;
495 		case Opt_unhide:
496 			uopt->flags |= (1 << UDF_FLAG_UNHIDE);
497 			break;
498 		case Opt_undelete:
499 			uopt->flags |= (1 << UDF_FLAG_UNDELETE);
500 			break;
501 		case Opt_noadinicb:
502 			uopt->flags &= ~(1 << UDF_FLAG_USE_AD_IN_ICB);
503 			break;
504 		case Opt_adinicb:
505 			uopt->flags |= (1 << UDF_FLAG_USE_AD_IN_ICB);
506 			break;
507 		case Opt_shortad:
508 			uopt->flags |= (1 << UDF_FLAG_USE_SHORT_AD);
509 			break;
510 		case Opt_longad:
511 			uopt->flags &= ~(1 << UDF_FLAG_USE_SHORT_AD);
512 			break;
513 		case Opt_gid:
514 			if (match_int(args, &option))
515 				return 0;
516 			uopt->gid = make_kgid(current_user_ns(), option);
517 			if (!gid_valid(uopt->gid))
518 				return 0;
519 			uopt->flags |= (1 << UDF_FLAG_GID_SET);
520 			break;
521 		case Opt_uid:
522 			if (match_int(args, &option))
523 				return 0;
524 			uopt->uid = make_kuid(current_user_ns(), option);
525 			if (!uid_valid(uopt->uid))
526 				return 0;
527 			uopt->flags |= (1 << UDF_FLAG_UID_SET);
528 			break;
529 		case Opt_umask:
530 			if (match_octal(args, &option))
531 				return 0;
532 			uopt->umask = option;
533 			break;
534 		case Opt_nostrict:
535 			uopt->flags &= ~(1 << UDF_FLAG_STRICT);
536 			break;
537 		case Opt_session:
538 			if (match_int(args, &option))
539 				return 0;
540 			uopt->session = option;
541 			if (!remount)
542 				uopt->flags |= (1 << UDF_FLAG_SESSION_SET);
543 			break;
544 		case Opt_lastblock:
545 			if (match_int(args, &option))
546 				return 0;
547 			uopt->lastblock = option;
548 			if (!remount)
549 				uopt->flags |= (1 << UDF_FLAG_LASTBLOCK_SET);
550 			break;
551 		case Opt_anchor:
552 			if (match_int(args, &option))
553 				return 0;
554 			uopt->anchor = option;
555 			break;
556 		case Opt_volume:
557 		case Opt_partition:
558 		case Opt_fileset:
559 		case Opt_rootdir:
560 			/* Ignored (never implemented properly) */
561 			break;
562 		case Opt_utf8:
563 			uopt->flags |= (1 << UDF_FLAG_UTF8);
564 			break;
565 		case Opt_iocharset:
566 			if (!remount) {
567 				if (uopt->nls_map)
568 					unload_nls(uopt->nls_map);
569 				/*
570 				 * load_nls() failure is handled later in
571 				 * udf_fill_super() after all options are
572 				 * parsed.
573 				 */
574 				uopt->nls_map = load_nls(args[0].from);
575 				uopt->flags |= (1 << UDF_FLAG_NLS_MAP);
576 			}
577 			break;
578 		case Opt_uforget:
579 			uopt->flags |= (1 << UDF_FLAG_UID_FORGET);
580 			break;
581 		case Opt_uignore:
582 		case Opt_gignore:
583 			/* These options are superseeded by uid=<number> */
584 			break;
585 		case Opt_gforget:
586 			uopt->flags |= (1 << UDF_FLAG_GID_FORGET);
587 			break;
588 		case Opt_fmode:
589 			if (match_octal(args, &option))
590 				return 0;
591 			uopt->fmode = option & 0777;
592 			break;
593 		case Opt_dmode:
594 			if (match_octal(args, &option))
595 				return 0;
596 			uopt->dmode = option & 0777;
597 			break;
598 		default:
599 			pr_err("bad mount option \"%s\" or missing value\n", p);
600 			return 0;
601 		}
602 	}
603 	return 1;
604 }
605 
606 static int udf_remount_fs(struct super_block *sb, int *flags, char *options)
607 {
608 	struct udf_options uopt;
609 	struct udf_sb_info *sbi = UDF_SB(sb);
610 	int error = 0;
611 
612 	if (!(*flags & SB_RDONLY) && UDF_QUERY_FLAG(sb, UDF_FLAG_RW_INCOMPAT))
613 		return -EACCES;
614 
615 	sync_filesystem(sb);
616 
617 	uopt.flags = sbi->s_flags;
618 	uopt.uid   = sbi->s_uid;
619 	uopt.gid   = sbi->s_gid;
620 	uopt.umask = sbi->s_umask;
621 	uopt.fmode = sbi->s_fmode;
622 	uopt.dmode = sbi->s_dmode;
623 	uopt.nls_map = NULL;
624 
625 	if (!udf_parse_options(options, &uopt, true))
626 		return -EINVAL;
627 
628 	write_lock(&sbi->s_cred_lock);
629 	sbi->s_flags = uopt.flags;
630 	sbi->s_uid   = uopt.uid;
631 	sbi->s_gid   = uopt.gid;
632 	sbi->s_umask = uopt.umask;
633 	sbi->s_fmode = uopt.fmode;
634 	sbi->s_dmode = uopt.dmode;
635 	write_unlock(&sbi->s_cred_lock);
636 
637 	if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
638 		goto out_unlock;
639 
640 	if (*flags & SB_RDONLY)
641 		udf_close_lvid(sb);
642 	else
643 		udf_open_lvid(sb);
644 
645 out_unlock:
646 	return error;
647 }
648 
649 /* Check Volume Structure Descriptors (ECMA 167 2/9.1) */
650 /* We also check any "CD-ROM Volume Descriptor Set" (ECMA 167 2/8.3.1) */
651 static loff_t udf_check_vsd(struct super_block *sb)
652 {
653 	struct volStructDesc *vsd = NULL;
654 	loff_t sector = VSD_FIRST_SECTOR_OFFSET;
655 	int sectorsize;
656 	struct buffer_head *bh = NULL;
657 	int nsr02 = 0;
658 	int nsr03 = 0;
659 	struct udf_sb_info *sbi;
660 
661 	sbi = UDF_SB(sb);
662 	if (sb->s_blocksize < sizeof(struct volStructDesc))
663 		sectorsize = sizeof(struct volStructDesc);
664 	else
665 		sectorsize = sb->s_blocksize;
666 
667 	sector += (((loff_t)sbi->s_session) << sb->s_blocksize_bits);
668 
669 	udf_debug("Starting at sector %u (%lu byte sectors)\n",
670 		  (unsigned int)(sector >> sb->s_blocksize_bits),
671 		  sb->s_blocksize);
672 	/* Process the sequence (if applicable). The hard limit on the sector
673 	 * offset is arbitrary, hopefully large enough so that all valid UDF
674 	 * filesystems will be recognised. There is no mention of an upper
675 	 * bound to the size of the volume recognition area in the standard.
676 	 *  The limit will prevent the code to read all the sectors of a
677 	 * specially crafted image (like a bluray disc full of CD001 sectors),
678 	 * potentially causing minutes or even hours of uninterruptible I/O
679 	 * activity. This actually happened with uninitialised SSD partitions
680 	 * (all 0xFF) before the check for the limit and all valid IDs were
681 	 * added */
682 	for (; !nsr02 && !nsr03 && sector < VSD_MAX_SECTOR_OFFSET;
683 	     sector += sectorsize) {
684 		/* Read a block */
685 		bh = udf_tread(sb, sector >> sb->s_blocksize_bits);
686 		if (!bh)
687 			break;
688 
689 		/* Look for ISO  descriptors */
690 		vsd = (struct volStructDesc *)(bh->b_data +
691 					      (sector & (sb->s_blocksize - 1)));
692 
693 		if (!strncmp(vsd->stdIdent, VSD_STD_ID_CD001,
694 				    VSD_STD_ID_LEN)) {
695 			switch (vsd->structType) {
696 			case 0:
697 				udf_debug("ISO9660 Boot Record found\n");
698 				break;
699 			case 1:
700 				udf_debug("ISO9660 Primary Volume Descriptor found\n");
701 				break;
702 			case 2:
703 				udf_debug("ISO9660 Supplementary Volume Descriptor found\n");
704 				break;
705 			case 3:
706 				udf_debug("ISO9660 Volume Partition Descriptor found\n");
707 				break;
708 			case 255:
709 				udf_debug("ISO9660 Volume Descriptor Set Terminator found\n");
710 				break;
711 			default:
712 				udf_debug("ISO9660 VRS (%u) found\n",
713 					  vsd->structType);
714 				break;
715 			}
716 		} else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BEA01,
717 				    VSD_STD_ID_LEN))
718 			; /* nothing */
719 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_TEA01,
720 				    VSD_STD_ID_LEN)) {
721 			brelse(bh);
722 			break;
723 		} else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR02,
724 				    VSD_STD_ID_LEN))
725 			nsr02 = sector;
726 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR03,
727 				    VSD_STD_ID_LEN))
728 			nsr03 = sector;
729 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BOOT2,
730 				    VSD_STD_ID_LEN))
731 			; /* nothing */
732 		else if (!strncmp(vsd->stdIdent, VSD_STD_ID_CDW02,
733 				    VSD_STD_ID_LEN))
734 			; /* nothing */
735 		else {
736 			/* invalid id : end of volume recognition area */
737 			brelse(bh);
738 			break;
739 		}
740 		brelse(bh);
741 	}
742 
743 	if (nsr03)
744 		return nsr03;
745 	else if (nsr02)
746 		return nsr02;
747 	else if (!bh && sector - (sbi->s_session << sb->s_blocksize_bits) ==
748 			VSD_FIRST_SECTOR_OFFSET)
749 		return -1;
750 	else
751 		return 0;
752 }
753 
754 static int udf_find_fileset(struct super_block *sb,
755 			    struct kernel_lb_addr *fileset,
756 			    struct kernel_lb_addr *root)
757 {
758 	struct buffer_head *bh = NULL;
759 	uint16_t ident;
760 
761 	if (fileset->logicalBlockNum != 0xFFFFFFFF ||
762 	    fileset->partitionReferenceNum != 0xFFFF) {
763 		bh = udf_read_ptagged(sb, fileset, 0, &ident);
764 
765 		if (!bh) {
766 			return 1;
767 		} else if (ident != TAG_IDENT_FSD) {
768 			brelse(bh);
769 			return 1;
770 		}
771 
772 		udf_debug("Fileset at block=%u, partition=%u\n",
773 			  fileset->logicalBlockNum,
774 			  fileset->partitionReferenceNum);
775 
776 		UDF_SB(sb)->s_partition = fileset->partitionReferenceNum;
777 		udf_load_fileset(sb, bh, root);
778 		brelse(bh);
779 		return 0;
780 	}
781 	return 1;
782 }
783 
784 /*
785  * Load primary Volume Descriptor Sequence
786  *
787  * Return <0 on error, 0 on success. -EAGAIN is special meaning next sequence
788  * should be tried.
789  */
790 static int udf_load_pvoldesc(struct super_block *sb, sector_t block)
791 {
792 	struct primaryVolDesc *pvoldesc;
793 	uint8_t *outstr;
794 	struct buffer_head *bh;
795 	uint16_t ident;
796 	int ret = -ENOMEM;
797 #ifdef UDFFS_DEBUG
798 	struct timestamp *ts;
799 #endif
800 
801 	outstr = kmalloc(128, GFP_NOFS);
802 	if (!outstr)
803 		return -ENOMEM;
804 
805 	bh = udf_read_tagged(sb, block, block, &ident);
806 	if (!bh) {
807 		ret = -EAGAIN;
808 		goto out2;
809 	}
810 
811 	if (ident != TAG_IDENT_PVD) {
812 		ret = -EIO;
813 		goto out_bh;
814 	}
815 
816 	pvoldesc = (struct primaryVolDesc *)bh->b_data;
817 
818 	udf_disk_stamp_to_time(&UDF_SB(sb)->s_record_time,
819 			      pvoldesc->recordingDateAndTime);
820 #ifdef UDFFS_DEBUG
821 	ts = &pvoldesc->recordingDateAndTime;
822 	udf_debug("recording time %04u/%02u/%02u %02u:%02u (%x)\n",
823 		  le16_to_cpu(ts->year), ts->month, ts->day, ts->hour,
824 		  ts->minute, le16_to_cpu(ts->typeAndTimezone));
825 #endif
826 
827 
828 	ret = udf_dstrCS0toChar(sb, outstr, 31, pvoldesc->volIdent, 32);
829 	if (ret < 0) {
830 		strcpy(UDF_SB(sb)->s_volume_ident, "InvalidName");
831 		pr_warn("incorrect volume identification, setting to "
832 			"'InvalidName'\n");
833 	} else {
834 		strncpy(UDF_SB(sb)->s_volume_ident, outstr, ret);
835 	}
836 	udf_debug("volIdent[] = '%s'\n", UDF_SB(sb)->s_volume_ident);
837 
838 	ret = udf_dstrCS0toChar(sb, outstr, 127, pvoldesc->volSetIdent, 128);
839 	if (ret < 0) {
840 		ret = 0;
841 		goto out_bh;
842 	}
843 	outstr[ret] = 0;
844 	udf_debug("volSetIdent[] = '%s'\n", outstr);
845 
846 	ret = 0;
847 out_bh:
848 	brelse(bh);
849 out2:
850 	kfree(outstr);
851 	return ret;
852 }
853 
854 struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
855 					u32 meta_file_loc, u32 partition_ref)
856 {
857 	struct kernel_lb_addr addr;
858 	struct inode *metadata_fe;
859 
860 	addr.logicalBlockNum = meta_file_loc;
861 	addr.partitionReferenceNum = partition_ref;
862 
863 	metadata_fe = udf_iget_special(sb, &addr);
864 
865 	if (IS_ERR(metadata_fe)) {
866 		udf_warn(sb, "metadata inode efe not found\n");
867 		return metadata_fe;
868 	}
869 	if (UDF_I(metadata_fe)->i_alloc_type != ICBTAG_FLAG_AD_SHORT) {
870 		udf_warn(sb, "metadata inode efe does not have short allocation descriptors!\n");
871 		iput(metadata_fe);
872 		return ERR_PTR(-EIO);
873 	}
874 
875 	return metadata_fe;
876 }
877 
878 static int udf_load_metadata_files(struct super_block *sb, int partition,
879 				   int type1_index)
880 {
881 	struct udf_sb_info *sbi = UDF_SB(sb);
882 	struct udf_part_map *map;
883 	struct udf_meta_data *mdata;
884 	struct kernel_lb_addr addr;
885 	struct inode *fe;
886 
887 	map = &sbi->s_partmaps[partition];
888 	mdata = &map->s_type_specific.s_metadata;
889 	mdata->s_phys_partition_ref = type1_index;
890 
891 	/* metadata address */
892 	udf_debug("Metadata file location: block = %u part = %u\n",
893 		  mdata->s_meta_file_loc, mdata->s_phys_partition_ref);
894 
895 	fe = udf_find_metadata_inode_efe(sb, mdata->s_meta_file_loc,
896 					 mdata->s_phys_partition_ref);
897 	if (IS_ERR(fe)) {
898 		/* mirror file entry */
899 		udf_debug("Mirror metadata file location: block = %u part = %u\n",
900 			  mdata->s_mirror_file_loc, mdata->s_phys_partition_ref);
901 
902 		fe = udf_find_metadata_inode_efe(sb, mdata->s_mirror_file_loc,
903 						 mdata->s_phys_partition_ref);
904 
905 		if (IS_ERR(fe)) {
906 			udf_err(sb, "Both metadata and mirror metadata inode efe can not found\n");
907 			return PTR_ERR(fe);
908 		}
909 		mdata->s_mirror_fe = fe;
910 	} else
911 		mdata->s_metadata_fe = fe;
912 
913 
914 	/*
915 	 * bitmap file entry
916 	 * Note:
917 	 * Load only if bitmap file location differs from 0xFFFFFFFF (DCN-5102)
918 	*/
919 	if (mdata->s_bitmap_file_loc != 0xFFFFFFFF) {
920 		addr.logicalBlockNum = mdata->s_bitmap_file_loc;
921 		addr.partitionReferenceNum = mdata->s_phys_partition_ref;
922 
923 		udf_debug("Bitmap file location: block = %u part = %u\n",
924 			  addr.logicalBlockNum, addr.partitionReferenceNum);
925 
926 		fe = udf_iget_special(sb, &addr);
927 		if (IS_ERR(fe)) {
928 			if (sb_rdonly(sb))
929 				udf_warn(sb, "bitmap inode efe not found but it's ok since the disc is mounted read-only\n");
930 			else {
931 				udf_err(sb, "bitmap inode efe not found and attempted read-write mount\n");
932 				return PTR_ERR(fe);
933 			}
934 		} else
935 			mdata->s_bitmap_fe = fe;
936 	}
937 
938 	udf_debug("udf_load_metadata_files Ok\n");
939 	return 0;
940 }
941 
942 static void udf_load_fileset(struct super_block *sb, struct buffer_head *bh,
943 			     struct kernel_lb_addr *root)
944 {
945 	struct fileSetDesc *fset;
946 
947 	fset = (struct fileSetDesc *)bh->b_data;
948 
949 	*root = lelb_to_cpu(fset->rootDirectoryICB.extLocation);
950 
951 	UDF_SB(sb)->s_serial_number = le16_to_cpu(fset->descTag.tagSerialNum);
952 
953 	udf_debug("Rootdir at block=%u, partition=%u\n",
954 		  root->logicalBlockNum, root->partitionReferenceNum);
955 }
956 
957 int udf_compute_nr_groups(struct super_block *sb, u32 partition)
958 {
959 	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
960 	return DIV_ROUND_UP(map->s_partition_len +
961 			    (sizeof(struct spaceBitmapDesc) << 3),
962 			    sb->s_blocksize * 8);
963 }
964 
965 static struct udf_bitmap *udf_sb_alloc_bitmap(struct super_block *sb, u32 index)
966 {
967 	struct udf_bitmap *bitmap;
968 	int nr_groups;
969 	int size;
970 
971 	nr_groups = udf_compute_nr_groups(sb, index);
972 	size = sizeof(struct udf_bitmap) +
973 		(sizeof(struct buffer_head *) * nr_groups);
974 
975 	if (size <= PAGE_SIZE)
976 		bitmap = kzalloc(size, GFP_KERNEL);
977 	else
978 		bitmap = vzalloc(size); /* TODO: get rid of vzalloc */
979 
980 	if (!bitmap)
981 		return NULL;
982 
983 	bitmap->s_nr_groups = nr_groups;
984 	return bitmap;
985 }
986 
987 static int check_partition_desc(struct super_block *sb,
988 				struct partitionDesc *p,
989 				struct udf_part_map *map)
990 {
991 	bool umap, utable, fmap, ftable;
992 	struct partitionHeaderDesc *phd;
993 
994 	switch (le32_to_cpu(p->accessType)) {
995 	case PD_ACCESS_TYPE_READ_ONLY:
996 	case PD_ACCESS_TYPE_WRITE_ONCE:
997 	case PD_ACCESS_TYPE_REWRITABLE:
998 	case PD_ACCESS_TYPE_NONE:
999 		goto force_ro;
1000 	}
1001 
1002 	/* No Partition Header Descriptor? */
1003 	if (strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR02) &&
1004 	    strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR03))
1005 		goto force_ro;
1006 
1007 	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1008 	utable = phd->unallocSpaceTable.extLength;
1009 	umap = phd->unallocSpaceBitmap.extLength;
1010 	ftable = phd->freedSpaceTable.extLength;
1011 	fmap = phd->freedSpaceBitmap.extLength;
1012 
1013 	/* No allocation info? */
1014 	if (!utable && !umap && !ftable && !fmap)
1015 		goto force_ro;
1016 
1017 	/* We don't support blocks that require erasing before overwrite */
1018 	if (ftable || fmap)
1019 		goto force_ro;
1020 	/* UDF 2.60: 2.3.3 - no mixing of tables & bitmaps, no VAT. */
1021 	if (utable && umap)
1022 		goto force_ro;
1023 
1024 	if (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1025 	    map->s_partition_type == UDF_VIRTUAL_MAP20)
1026 		goto force_ro;
1027 
1028 	return 0;
1029 force_ro:
1030 	if (!sb_rdonly(sb))
1031 		return -EACCES;
1032 	UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1033 	return 0;
1034 }
1035 
1036 static int udf_fill_partdesc_info(struct super_block *sb,
1037 		struct partitionDesc *p, int p_index)
1038 {
1039 	struct udf_part_map *map;
1040 	struct udf_sb_info *sbi = UDF_SB(sb);
1041 	struct partitionHeaderDesc *phd;
1042 	int err;
1043 
1044 	map = &sbi->s_partmaps[p_index];
1045 
1046 	map->s_partition_len = le32_to_cpu(p->partitionLength); /* blocks */
1047 	map->s_partition_root = le32_to_cpu(p->partitionStartingLocation);
1048 
1049 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_READ_ONLY))
1050 		map->s_partition_flags |= UDF_PART_FLAG_READ_ONLY;
1051 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_WRITE_ONCE))
1052 		map->s_partition_flags |= UDF_PART_FLAG_WRITE_ONCE;
1053 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_REWRITABLE))
1054 		map->s_partition_flags |= UDF_PART_FLAG_REWRITABLE;
1055 	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_OVERWRITABLE))
1056 		map->s_partition_flags |= UDF_PART_FLAG_OVERWRITABLE;
1057 
1058 	udf_debug("Partition (%d type %x) starts at physical %u, block length %u\n",
1059 		  p_index, map->s_partition_type,
1060 		  map->s_partition_root, map->s_partition_len);
1061 
1062 	err = check_partition_desc(sb, p, map);
1063 	if (err)
1064 		return err;
1065 
1066 	/*
1067 	 * Skip loading allocation info it we cannot ever write to the fs.
1068 	 * This is a correctness thing as we may have decided to force ro mount
1069 	 * to avoid allocation info we don't support.
1070 	 */
1071 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_RW_INCOMPAT))
1072 		return 0;
1073 
1074 	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1075 	if (phd->unallocSpaceTable.extLength) {
1076 		struct kernel_lb_addr loc = {
1077 			.logicalBlockNum = le32_to_cpu(
1078 				phd->unallocSpaceTable.extPosition),
1079 			.partitionReferenceNum = p_index,
1080 		};
1081 		struct inode *inode;
1082 
1083 		inode = udf_iget_special(sb, &loc);
1084 		if (IS_ERR(inode)) {
1085 			udf_debug("cannot load unallocSpaceTable (part %d)\n",
1086 				  p_index);
1087 			return PTR_ERR(inode);
1088 		}
1089 		map->s_uspace.s_table = inode;
1090 		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_TABLE;
1091 		udf_debug("unallocSpaceTable (part %d) @ %lu\n",
1092 			  p_index, map->s_uspace.s_table->i_ino);
1093 	}
1094 
1095 	if (phd->unallocSpaceBitmap.extLength) {
1096 		struct udf_bitmap *bitmap = udf_sb_alloc_bitmap(sb, p_index);
1097 		if (!bitmap)
1098 			return -ENOMEM;
1099 		map->s_uspace.s_bitmap = bitmap;
1100 		bitmap->s_extPosition = le32_to_cpu(
1101 				phd->unallocSpaceBitmap.extPosition);
1102 		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_BITMAP;
1103 		udf_debug("unallocSpaceBitmap (part %d) @ %u\n",
1104 			  p_index, bitmap->s_extPosition);
1105 	}
1106 
1107 	return 0;
1108 }
1109 
1110 static void udf_find_vat_block(struct super_block *sb, int p_index,
1111 			       int type1_index, sector_t start_block)
1112 {
1113 	struct udf_sb_info *sbi = UDF_SB(sb);
1114 	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1115 	sector_t vat_block;
1116 	struct kernel_lb_addr ino;
1117 	struct inode *inode;
1118 
1119 	/*
1120 	 * VAT file entry is in the last recorded block. Some broken disks have
1121 	 * it a few blocks before so try a bit harder...
1122 	 */
1123 	ino.partitionReferenceNum = type1_index;
1124 	for (vat_block = start_block;
1125 	     vat_block >= map->s_partition_root &&
1126 	     vat_block >= start_block - 3; vat_block--) {
1127 		ino.logicalBlockNum = vat_block - map->s_partition_root;
1128 		inode = udf_iget_special(sb, &ino);
1129 		if (!IS_ERR(inode)) {
1130 			sbi->s_vat_inode = inode;
1131 			break;
1132 		}
1133 	}
1134 }
1135 
1136 static int udf_load_vat(struct super_block *sb, int p_index, int type1_index)
1137 {
1138 	struct udf_sb_info *sbi = UDF_SB(sb);
1139 	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1140 	struct buffer_head *bh = NULL;
1141 	struct udf_inode_info *vati;
1142 	uint32_t pos;
1143 	struct virtualAllocationTable20 *vat20;
1144 	sector_t blocks = i_size_read(sb->s_bdev->bd_inode) >>
1145 			  sb->s_blocksize_bits;
1146 
1147 	udf_find_vat_block(sb, p_index, type1_index, sbi->s_last_block);
1148 	if (!sbi->s_vat_inode &&
1149 	    sbi->s_last_block != blocks - 1) {
1150 		pr_notice("Failed to read VAT inode from the last recorded block (%lu), retrying with the last block of the device (%lu).\n",
1151 			  (unsigned long)sbi->s_last_block,
1152 			  (unsigned long)blocks - 1);
1153 		udf_find_vat_block(sb, p_index, type1_index, blocks - 1);
1154 	}
1155 	if (!sbi->s_vat_inode)
1156 		return -EIO;
1157 
1158 	if (map->s_partition_type == UDF_VIRTUAL_MAP15) {
1159 		map->s_type_specific.s_virtual.s_start_offset = 0;
1160 		map->s_type_specific.s_virtual.s_num_entries =
1161 			(sbi->s_vat_inode->i_size - 36) >> 2;
1162 	} else if (map->s_partition_type == UDF_VIRTUAL_MAP20) {
1163 		vati = UDF_I(sbi->s_vat_inode);
1164 		if (vati->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1165 			pos = udf_block_map(sbi->s_vat_inode, 0);
1166 			bh = sb_bread(sb, pos);
1167 			if (!bh)
1168 				return -EIO;
1169 			vat20 = (struct virtualAllocationTable20 *)bh->b_data;
1170 		} else {
1171 			vat20 = (struct virtualAllocationTable20 *)
1172 							vati->i_ext.i_data;
1173 		}
1174 
1175 		map->s_type_specific.s_virtual.s_start_offset =
1176 			le16_to_cpu(vat20->lengthHeader);
1177 		map->s_type_specific.s_virtual.s_num_entries =
1178 			(sbi->s_vat_inode->i_size -
1179 				map->s_type_specific.s_virtual.
1180 					s_start_offset) >> 2;
1181 		brelse(bh);
1182 	}
1183 	return 0;
1184 }
1185 
1186 /*
1187  * Load partition descriptor block
1188  *
1189  * Returns <0 on error, 0 on success, -EAGAIN is special - try next descriptor
1190  * sequence.
1191  */
1192 static int udf_load_partdesc(struct super_block *sb, sector_t block)
1193 {
1194 	struct buffer_head *bh;
1195 	struct partitionDesc *p;
1196 	struct udf_part_map *map;
1197 	struct udf_sb_info *sbi = UDF_SB(sb);
1198 	int i, type1_idx;
1199 	uint16_t partitionNumber;
1200 	uint16_t ident;
1201 	int ret;
1202 
1203 	bh = udf_read_tagged(sb, block, block, &ident);
1204 	if (!bh)
1205 		return -EAGAIN;
1206 	if (ident != TAG_IDENT_PD) {
1207 		ret = 0;
1208 		goto out_bh;
1209 	}
1210 
1211 	p = (struct partitionDesc *)bh->b_data;
1212 	partitionNumber = le16_to_cpu(p->partitionNumber);
1213 
1214 	/* First scan for TYPE1 and SPARABLE partitions */
1215 	for (i = 0; i < sbi->s_partitions; i++) {
1216 		map = &sbi->s_partmaps[i];
1217 		udf_debug("Searching map: (%u == %u)\n",
1218 			  map->s_partition_num, partitionNumber);
1219 		if (map->s_partition_num == partitionNumber &&
1220 		    (map->s_partition_type == UDF_TYPE1_MAP15 ||
1221 		     map->s_partition_type == UDF_SPARABLE_MAP15))
1222 			break;
1223 	}
1224 
1225 	if (i >= sbi->s_partitions) {
1226 		udf_debug("Partition (%u) not found in partition map\n",
1227 			  partitionNumber);
1228 		ret = 0;
1229 		goto out_bh;
1230 	}
1231 
1232 	ret = udf_fill_partdesc_info(sb, p, i);
1233 	if (ret < 0)
1234 		goto out_bh;
1235 
1236 	/*
1237 	 * Now rescan for VIRTUAL or METADATA partitions when SPARABLE and
1238 	 * PHYSICAL partitions are already set up
1239 	 */
1240 	type1_idx = i;
1241 #ifdef UDFFS_DEBUG
1242 	map = NULL; /* supress 'maybe used uninitialized' warning */
1243 #endif
1244 	for (i = 0; i < sbi->s_partitions; i++) {
1245 		map = &sbi->s_partmaps[i];
1246 
1247 		if (map->s_partition_num == partitionNumber &&
1248 		    (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1249 		     map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1250 		     map->s_partition_type == UDF_METADATA_MAP25))
1251 			break;
1252 	}
1253 
1254 	if (i >= sbi->s_partitions) {
1255 		ret = 0;
1256 		goto out_bh;
1257 	}
1258 
1259 	ret = udf_fill_partdesc_info(sb, p, i);
1260 	if (ret < 0)
1261 		goto out_bh;
1262 
1263 	if (map->s_partition_type == UDF_METADATA_MAP25) {
1264 		ret = udf_load_metadata_files(sb, i, type1_idx);
1265 		if (ret < 0) {
1266 			udf_err(sb, "error loading MetaData partition map %d\n",
1267 				i);
1268 			goto out_bh;
1269 		}
1270 	} else {
1271 		/*
1272 		 * If we have a partition with virtual map, we don't handle
1273 		 * writing to it (we overwrite blocks instead of relocating
1274 		 * them).
1275 		 */
1276 		if (!sb_rdonly(sb)) {
1277 			ret = -EACCES;
1278 			goto out_bh;
1279 		}
1280 		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1281 		ret = udf_load_vat(sb, i, type1_idx);
1282 		if (ret < 0)
1283 			goto out_bh;
1284 	}
1285 	ret = 0;
1286 out_bh:
1287 	/* In case loading failed, we handle cleanup in udf_fill_super */
1288 	brelse(bh);
1289 	return ret;
1290 }
1291 
1292 static int udf_load_sparable_map(struct super_block *sb,
1293 				 struct udf_part_map *map,
1294 				 struct sparablePartitionMap *spm)
1295 {
1296 	uint32_t loc;
1297 	uint16_t ident;
1298 	struct sparingTable *st;
1299 	struct udf_sparing_data *sdata = &map->s_type_specific.s_sparing;
1300 	int i;
1301 	struct buffer_head *bh;
1302 
1303 	map->s_partition_type = UDF_SPARABLE_MAP15;
1304 	sdata->s_packet_len = le16_to_cpu(spm->packetLength);
1305 	if (!is_power_of_2(sdata->s_packet_len)) {
1306 		udf_err(sb, "error loading logical volume descriptor: "
1307 			"Invalid packet length %u\n",
1308 			(unsigned)sdata->s_packet_len);
1309 		return -EIO;
1310 	}
1311 	if (spm->numSparingTables > 4) {
1312 		udf_err(sb, "error loading logical volume descriptor: "
1313 			"Too many sparing tables (%d)\n",
1314 			(int)spm->numSparingTables);
1315 		return -EIO;
1316 	}
1317 
1318 	for (i = 0; i < spm->numSparingTables; i++) {
1319 		loc = le32_to_cpu(spm->locSparingTable[i]);
1320 		bh = udf_read_tagged(sb, loc, loc, &ident);
1321 		if (!bh)
1322 			continue;
1323 
1324 		st = (struct sparingTable *)bh->b_data;
1325 		if (ident != 0 ||
1326 		    strncmp(st->sparingIdent.ident, UDF_ID_SPARING,
1327 			    strlen(UDF_ID_SPARING)) ||
1328 		    sizeof(*st) + le16_to_cpu(st->reallocationTableLen) >
1329 							sb->s_blocksize) {
1330 			brelse(bh);
1331 			continue;
1332 		}
1333 
1334 		sdata->s_spar_map[i] = bh;
1335 	}
1336 	map->s_partition_func = udf_get_pblock_spar15;
1337 	return 0;
1338 }
1339 
1340 static int udf_load_logicalvol(struct super_block *sb, sector_t block,
1341 			       struct kernel_lb_addr *fileset)
1342 {
1343 	struct logicalVolDesc *lvd;
1344 	int i, offset;
1345 	uint8_t type;
1346 	struct udf_sb_info *sbi = UDF_SB(sb);
1347 	struct genericPartitionMap *gpm;
1348 	uint16_t ident;
1349 	struct buffer_head *bh;
1350 	unsigned int table_len;
1351 	int ret;
1352 
1353 	bh = udf_read_tagged(sb, block, block, &ident);
1354 	if (!bh)
1355 		return -EAGAIN;
1356 	BUG_ON(ident != TAG_IDENT_LVD);
1357 	lvd = (struct logicalVolDesc *)bh->b_data;
1358 	table_len = le32_to_cpu(lvd->mapTableLength);
1359 	if (table_len > sb->s_blocksize - sizeof(*lvd)) {
1360 		udf_err(sb, "error loading logical volume descriptor: "
1361 			"Partition table too long (%u > %lu)\n", table_len,
1362 			sb->s_blocksize - sizeof(*lvd));
1363 		ret = -EIO;
1364 		goto out_bh;
1365 	}
1366 
1367 	ret = udf_sb_alloc_partition_maps(sb, le32_to_cpu(lvd->numPartitionMaps));
1368 	if (ret)
1369 		goto out_bh;
1370 
1371 	for (i = 0, offset = 0;
1372 	     i < sbi->s_partitions && offset < table_len;
1373 	     i++, offset += gpm->partitionMapLength) {
1374 		struct udf_part_map *map = &sbi->s_partmaps[i];
1375 		gpm = (struct genericPartitionMap *)
1376 				&(lvd->partitionMaps[offset]);
1377 		type = gpm->partitionMapType;
1378 		if (type == 1) {
1379 			struct genericPartitionMap1 *gpm1 =
1380 				(struct genericPartitionMap1 *)gpm;
1381 			map->s_partition_type = UDF_TYPE1_MAP15;
1382 			map->s_volumeseqnum = le16_to_cpu(gpm1->volSeqNum);
1383 			map->s_partition_num = le16_to_cpu(gpm1->partitionNum);
1384 			map->s_partition_func = NULL;
1385 		} else if (type == 2) {
1386 			struct udfPartitionMap2 *upm2 =
1387 						(struct udfPartitionMap2 *)gpm;
1388 			if (!strncmp(upm2->partIdent.ident, UDF_ID_VIRTUAL,
1389 						strlen(UDF_ID_VIRTUAL))) {
1390 				u16 suf =
1391 					le16_to_cpu(((__le16 *)upm2->partIdent.
1392 							identSuffix)[0]);
1393 				if (suf < 0x0200) {
1394 					map->s_partition_type =
1395 							UDF_VIRTUAL_MAP15;
1396 					map->s_partition_func =
1397 							udf_get_pblock_virt15;
1398 				} else {
1399 					map->s_partition_type =
1400 							UDF_VIRTUAL_MAP20;
1401 					map->s_partition_func =
1402 							udf_get_pblock_virt20;
1403 				}
1404 			} else if (!strncmp(upm2->partIdent.ident,
1405 						UDF_ID_SPARABLE,
1406 						strlen(UDF_ID_SPARABLE))) {
1407 				ret = udf_load_sparable_map(sb, map,
1408 					(struct sparablePartitionMap *)gpm);
1409 				if (ret < 0)
1410 					goto out_bh;
1411 			} else if (!strncmp(upm2->partIdent.ident,
1412 						UDF_ID_METADATA,
1413 						strlen(UDF_ID_METADATA))) {
1414 				struct udf_meta_data *mdata =
1415 					&map->s_type_specific.s_metadata;
1416 				struct metadataPartitionMap *mdm =
1417 						(struct metadataPartitionMap *)
1418 						&(lvd->partitionMaps[offset]);
1419 				udf_debug("Parsing Logical vol part %d type %u  id=%s\n",
1420 					  i, type, UDF_ID_METADATA);
1421 
1422 				map->s_partition_type = UDF_METADATA_MAP25;
1423 				map->s_partition_func = udf_get_pblock_meta25;
1424 
1425 				mdata->s_meta_file_loc   =
1426 					le32_to_cpu(mdm->metadataFileLoc);
1427 				mdata->s_mirror_file_loc =
1428 					le32_to_cpu(mdm->metadataMirrorFileLoc);
1429 				mdata->s_bitmap_file_loc =
1430 					le32_to_cpu(mdm->metadataBitmapFileLoc);
1431 				mdata->s_alloc_unit_size =
1432 					le32_to_cpu(mdm->allocUnitSize);
1433 				mdata->s_align_unit_size =
1434 					le16_to_cpu(mdm->alignUnitSize);
1435 				if (mdm->flags & 0x01)
1436 					mdata->s_flags |= MF_DUPLICATE_MD;
1437 
1438 				udf_debug("Metadata Ident suffix=0x%x\n",
1439 					  le16_to_cpu(*(__le16 *)
1440 						      mdm->partIdent.identSuffix));
1441 				udf_debug("Metadata part num=%u\n",
1442 					  le16_to_cpu(mdm->partitionNum));
1443 				udf_debug("Metadata part alloc unit size=%u\n",
1444 					  le32_to_cpu(mdm->allocUnitSize));
1445 				udf_debug("Metadata file loc=%u\n",
1446 					  le32_to_cpu(mdm->metadataFileLoc));
1447 				udf_debug("Mirror file loc=%u\n",
1448 					  le32_to_cpu(mdm->metadataMirrorFileLoc));
1449 				udf_debug("Bitmap file loc=%u\n",
1450 					  le32_to_cpu(mdm->metadataBitmapFileLoc));
1451 				udf_debug("Flags: %d %u\n",
1452 					  mdata->s_flags, mdm->flags);
1453 			} else {
1454 				udf_debug("Unknown ident: %s\n",
1455 					  upm2->partIdent.ident);
1456 				continue;
1457 			}
1458 			map->s_volumeseqnum = le16_to_cpu(upm2->volSeqNum);
1459 			map->s_partition_num = le16_to_cpu(upm2->partitionNum);
1460 		}
1461 		udf_debug("Partition (%d:%u) type %u on volume %u\n",
1462 			  i, map->s_partition_num, type, map->s_volumeseqnum);
1463 	}
1464 
1465 	if (fileset) {
1466 		struct long_ad *la = (struct long_ad *)&(lvd->logicalVolContentsUse[0]);
1467 
1468 		*fileset = lelb_to_cpu(la->extLocation);
1469 		udf_debug("FileSet found in LogicalVolDesc at block=%u, partition=%u\n",
1470 			  fileset->logicalBlockNum,
1471 			  fileset->partitionReferenceNum);
1472 	}
1473 	if (lvd->integritySeqExt.extLength)
1474 		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
1475 	ret = 0;
1476 
1477 	if (!sbi->s_lvid_bh) {
1478 		/* We can't generate unique IDs without a valid LVID */
1479 		if (sb_rdonly(sb)) {
1480 			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1481 		} else {
1482 			udf_warn(sb, "Damaged or missing LVID, forcing "
1483 				     "readonly mount\n");
1484 			ret = -EACCES;
1485 		}
1486 	}
1487 out_bh:
1488 	brelse(bh);
1489 	return ret;
1490 }
1491 
1492 /*
1493  * Find the prevailing Logical Volume Integrity Descriptor.
1494  */
1495 static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_ad loc)
1496 {
1497 	struct buffer_head *bh, *final_bh;
1498 	uint16_t ident;
1499 	struct udf_sb_info *sbi = UDF_SB(sb);
1500 	struct logicalVolIntegrityDesc *lvid;
1501 	int indirections = 0;
1502 
1503 	while (++indirections <= UDF_MAX_LVID_NESTING) {
1504 		final_bh = NULL;
1505 		while (loc.extLength > 0 &&
1506 			(bh = udf_read_tagged(sb, loc.extLocation,
1507 					loc.extLocation, &ident))) {
1508 			if (ident != TAG_IDENT_LVID) {
1509 				brelse(bh);
1510 				break;
1511 			}
1512 
1513 			brelse(final_bh);
1514 			final_bh = bh;
1515 
1516 			loc.extLength -= sb->s_blocksize;
1517 			loc.extLocation++;
1518 		}
1519 
1520 		if (!final_bh)
1521 			return;
1522 
1523 		brelse(sbi->s_lvid_bh);
1524 		sbi->s_lvid_bh = final_bh;
1525 
1526 		lvid = (struct logicalVolIntegrityDesc *)final_bh->b_data;
1527 		if (lvid->nextIntegrityExt.extLength == 0)
1528 			return;
1529 
1530 		loc = leea_to_cpu(lvid->nextIntegrityExt);
1531 	}
1532 
1533 	udf_warn(sb, "Too many LVID indirections (max %u), ignoring.\n",
1534 		UDF_MAX_LVID_NESTING);
1535 	brelse(sbi->s_lvid_bh);
1536 	sbi->s_lvid_bh = NULL;
1537 }
1538 
1539 /*
1540  * Step for reallocation of table of partition descriptor sequence numbers.
1541  * Must be power of 2.
1542  */
1543 #define PART_DESC_ALLOC_STEP 32
1544 
1545 struct part_desc_seq_scan_data {
1546 	struct udf_vds_record rec;
1547 	u32 partnum;
1548 };
1549 
1550 struct desc_seq_scan_data {
1551 	struct udf_vds_record vds[VDS_POS_LENGTH];
1552 	unsigned int size_part_descs;
1553 	unsigned int num_part_descs;
1554 	struct part_desc_seq_scan_data *part_descs_loc;
1555 };
1556 
1557 static struct udf_vds_record *handle_partition_descriptor(
1558 				struct buffer_head *bh,
1559 				struct desc_seq_scan_data *data)
1560 {
1561 	struct partitionDesc *desc = (struct partitionDesc *)bh->b_data;
1562 	int partnum;
1563 	int i;
1564 
1565 	partnum = le16_to_cpu(desc->partitionNumber);
1566 	for (i = 0; i < data->num_part_descs; i++)
1567 		if (partnum == data->part_descs_loc[i].partnum)
1568 			return &(data->part_descs_loc[i].rec);
1569 	if (data->num_part_descs >= data->size_part_descs) {
1570 		struct part_desc_seq_scan_data *new_loc;
1571 		unsigned int new_size = ALIGN(partnum, PART_DESC_ALLOC_STEP);
1572 
1573 		new_loc = kcalloc(new_size, sizeof(*new_loc), GFP_KERNEL);
1574 		if (!new_loc)
1575 			return ERR_PTR(-ENOMEM);
1576 		memcpy(new_loc, data->part_descs_loc,
1577 		       data->size_part_descs * sizeof(*new_loc));
1578 		kfree(data->part_descs_loc);
1579 		data->part_descs_loc = new_loc;
1580 		data->size_part_descs = new_size;
1581 	}
1582 	return &(data->part_descs_loc[data->num_part_descs++].rec);
1583 }
1584 
1585 
1586 static struct udf_vds_record *get_volume_descriptor_record(uint16_t ident,
1587 		struct buffer_head *bh, struct desc_seq_scan_data *data)
1588 {
1589 	switch (ident) {
1590 	case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1591 		return &(data->vds[VDS_POS_PRIMARY_VOL_DESC]);
1592 	case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1593 		return &(data->vds[VDS_POS_IMP_USE_VOL_DESC]);
1594 	case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1595 		return &(data->vds[VDS_POS_LOGICAL_VOL_DESC]);
1596 	case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1597 		return &(data->vds[VDS_POS_UNALLOC_SPACE_DESC]);
1598 	case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1599 		return handle_partition_descriptor(bh, data);
1600 	}
1601 	return NULL;
1602 }
1603 
1604 /*
1605  * Process a main/reserve volume descriptor sequence.
1606  *   @block		First block of first extent of the sequence.
1607  *   @lastblock		Lastblock of first extent of the sequence.
1608  *   @fileset		There we store extent containing root fileset
1609  *
1610  * Returns <0 on error, 0 on success. -EAGAIN is special - try next descriptor
1611  * sequence
1612  */
1613 static noinline int udf_process_sequence(
1614 		struct super_block *sb,
1615 		sector_t block, sector_t lastblock,
1616 		struct kernel_lb_addr *fileset)
1617 {
1618 	struct buffer_head *bh = NULL;
1619 	struct udf_vds_record *curr;
1620 	struct generic_desc *gd;
1621 	struct volDescPtr *vdp;
1622 	bool done = false;
1623 	uint32_t vdsn;
1624 	uint16_t ident;
1625 	int ret;
1626 	unsigned int indirections = 0;
1627 	struct desc_seq_scan_data data;
1628 	unsigned int i;
1629 
1630 	memset(data.vds, 0, sizeof(struct udf_vds_record) * VDS_POS_LENGTH);
1631 	data.size_part_descs = PART_DESC_ALLOC_STEP;
1632 	data.num_part_descs = 0;
1633 	data.part_descs_loc = kcalloc(data.size_part_descs,
1634 				      sizeof(*data.part_descs_loc),
1635 				      GFP_KERNEL);
1636 	if (!data.part_descs_loc)
1637 		return -ENOMEM;
1638 
1639 	/*
1640 	 * Read the main descriptor sequence and find which descriptors
1641 	 * are in it.
1642 	 */
1643 	for (; (!done && block <= lastblock); block++) {
1644 		bh = udf_read_tagged(sb, block, block, &ident);
1645 		if (!bh)
1646 			break;
1647 
1648 		/* Process each descriptor (ISO 13346 3/8.3-8.4) */
1649 		gd = (struct generic_desc *)bh->b_data;
1650 		vdsn = le32_to_cpu(gd->volDescSeqNum);
1651 		switch (ident) {
1652 		case TAG_IDENT_VDP: /* ISO 13346 3/10.3 */
1653 			if (++indirections > UDF_MAX_TD_NESTING) {
1654 				udf_err(sb, "too many Volume Descriptor "
1655 					"Pointers (max %u supported)\n",
1656 					UDF_MAX_TD_NESTING);
1657 				brelse(bh);
1658 				return -EIO;
1659 			}
1660 
1661 			vdp = (struct volDescPtr *)bh->b_data;
1662 			block = le32_to_cpu(vdp->nextVolDescSeqExt.extLocation);
1663 			lastblock = le32_to_cpu(
1664 				vdp->nextVolDescSeqExt.extLength) >>
1665 				sb->s_blocksize_bits;
1666 			lastblock += block - 1;
1667 			/* For loop is going to increment 'block' again */
1668 			block--;
1669 			break;
1670 		case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1671 		case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1672 		case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1673 		case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1674 		case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1675 			curr = get_volume_descriptor_record(ident, bh, &data);
1676 			if (IS_ERR(curr)) {
1677 				brelse(bh);
1678 				return PTR_ERR(curr);
1679 			}
1680 			/* Descriptor we don't care about? */
1681 			if (!curr)
1682 				break;
1683 			if (vdsn >= curr->volDescSeqNum) {
1684 				curr->volDescSeqNum = vdsn;
1685 				curr->block = block;
1686 			}
1687 			break;
1688 		case TAG_IDENT_TD: /* ISO 13346 3/10.9 */
1689 			done = true;
1690 			break;
1691 		}
1692 		brelse(bh);
1693 	}
1694 	/*
1695 	 * Now read interesting descriptors again and process them
1696 	 * in a suitable order
1697 	 */
1698 	if (!data.vds[VDS_POS_PRIMARY_VOL_DESC].block) {
1699 		udf_err(sb, "Primary Volume Descriptor not found!\n");
1700 		return -EAGAIN;
1701 	}
1702 	ret = udf_load_pvoldesc(sb, data.vds[VDS_POS_PRIMARY_VOL_DESC].block);
1703 	if (ret < 0)
1704 		return ret;
1705 
1706 	if (data.vds[VDS_POS_LOGICAL_VOL_DESC].block) {
1707 		ret = udf_load_logicalvol(sb,
1708 				data.vds[VDS_POS_LOGICAL_VOL_DESC].block,
1709 				fileset);
1710 		if (ret < 0)
1711 			return ret;
1712 	}
1713 
1714 	/* Now handle prevailing Partition Descriptors */
1715 	for (i = 0; i < data.num_part_descs; i++) {
1716 		ret = udf_load_partdesc(sb, data.part_descs_loc[i].rec.block);
1717 		if (ret < 0)
1718 			return ret;
1719 	}
1720 
1721 	return 0;
1722 }
1723 
1724 /*
1725  * Load Volume Descriptor Sequence described by anchor in bh
1726  *
1727  * Returns <0 on error, 0 on success
1728  */
1729 static int udf_load_sequence(struct super_block *sb, struct buffer_head *bh,
1730 			     struct kernel_lb_addr *fileset)
1731 {
1732 	struct anchorVolDescPtr *anchor;
1733 	sector_t main_s, main_e, reserve_s, reserve_e;
1734 	int ret;
1735 
1736 	anchor = (struct anchorVolDescPtr *)bh->b_data;
1737 
1738 	/* Locate the main sequence */
1739 	main_s = le32_to_cpu(anchor->mainVolDescSeqExt.extLocation);
1740 	main_e = le32_to_cpu(anchor->mainVolDescSeqExt.extLength);
1741 	main_e = main_e >> sb->s_blocksize_bits;
1742 	main_e += main_s - 1;
1743 
1744 	/* Locate the reserve sequence */
1745 	reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
1746 	reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
1747 	reserve_e = reserve_e >> sb->s_blocksize_bits;
1748 	reserve_e += reserve_s - 1;
1749 
1750 	/* Process the main & reserve sequences */
1751 	/* responsible for finding the PartitionDesc(s) */
1752 	ret = udf_process_sequence(sb, main_s, main_e, fileset);
1753 	if (ret != -EAGAIN)
1754 		return ret;
1755 	udf_sb_free_partitions(sb);
1756 	ret = udf_process_sequence(sb, reserve_s, reserve_e, fileset);
1757 	if (ret < 0) {
1758 		udf_sb_free_partitions(sb);
1759 		/* No sequence was OK, return -EIO */
1760 		if (ret == -EAGAIN)
1761 			ret = -EIO;
1762 	}
1763 	return ret;
1764 }
1765 
1766 /*
1767  * Check whether there is an anchor block in the given block and
1768  * load Volume Descriptor Sequence if so.
1769  *
1770  * Returns <0 on error, 0 on success, -EAGAIN is special - try next anchor
1771  * block
1772  */
1773 static int udf_check_anchor_block(struct super_block *sb, sector_t block,
1774 				  struct kernel_lb_addr *fileset)
1775 {
1776 	struct buffer_head *bh;
1777 	uint16_t ident;
1778 	int ret;
1779 
1780 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV) &&
1781 	    udf_fixed_to_variable(block) >=
1782 	    i_size_read(sb->s_bdev->bd_inode) >> sb->s_blocksize_bits)
1783 		return -EAGAIN;
1784 
1785 	bh = udf_read_tagged(sb, block, block, &ident);
1786 	if (!bh)
1787 		return -EAGAIN;
1788 	if (ident != TAG_IDENT_AVDP) {
1789 		brelse(bh);
1790 		return -EAGAIN;
1791 	}
1792 	ret = udf_load_sequence(sb, bh, fileset);
1793 	brelse(bh);
1794 	return ret;
1795 }
1796 
1797 /*
1798  * Search for an anchor volume descriptor pointer.
1799  *
1800  * Returns < 0 on error, 0 on success. -EAGAIN is special - try next set
1801  * of anchors.
1802  */
1803 static int udf_scan_anchors(struct super_block *sb, sector_t *lastblock,
1804 			    struct kernel_lb_addr *fileset)
1805 {
1806 	sector_t last[6];
1807 	int i;
1808 	struct udf_sb_info *sbi = UDF_SB(sb);
1809 	int last_count = 0;
1810 	int ret;
1811 
1812 	/* First try user provided anchor */
1813 	if (sbi->s_anchor) {
1814 		ret = udf_check_anchor_block(sb, sbi->s_anchor, fileset);
1815 		if (ret != -EAGAIN)
1816 			return ret;
1817 	}
1818 	/*
1819 	 * according to spec, anchor is in either:
1820 	 *     block 256
1821 	 *     lastblock-256
1822 	 *     lastblock
1823 	 *  however, if the disc isn't closed, it could be 512.
1824 	 */
1825 	ret = udf_check_anchor_block(sb, sbi->s_session + 256, fileset);
1826 	if (ret != -EAGAIN)
1827 		return ret;
1828 	/*
1829 	 * The trouble is which block is the last one. Drives often misreport
1830 	 * this so we try various possibilities.
1831 	 */
1832 	last[last_count++] = *lastblock;
1833 	if (*lastblock >= 1)
1834 		last[last_count++] = *lastblock - 1;
1835 	last[last_count++] = *lastblock + 1;
1836 	if (*lastblock >= 2)
1837 		last[last_count++] = *lastblock - 2;
1838 	if (*lastblock >= 150)
1839 		last[last_count++] = *lastblock - 150;
1840 	if (*lastblock >= 152)
1841 		last[last_count++] = *lastblock - 152;
1842 
1843 	for (i = 0; i < last_count; i++) {
1844 		if (last[i] >= i_size_read(sb->s_bdev->bd_inode) >>
1845 				sb->s_blocksize_bits)
1846 			continue;
1847 		ret = udf_check_anchor_block(sb, last[i], fileset);
1848 		if (ret != -EAGAIN) {
1849 			if (!ret)
1850 				*lastblock = last[i];
1851 			return ret;
1852 		}
1853 		if (last[i] < 256)
1854 			continue;
1855 		ret = udf_check_anchor_block(sb, last[i] - 256, fileset);
1856 		if (ret != -EAGAIN) {
1857 			if (!ret)
1858 				*lastblock = last[i];
1859 			return ret;
1860 		}
1861 	}
1862 
1863 	/* Finally try block 512 in case media is open */
1864 	return udf_check_anchor_block(sb, sbi->s_session + 512, fileset);
1865 }
1866 
1867 /*
1868  * Find an anchor volume descriptor and load Volume Descriptor Sequence from
1869  * area specified by it. The function expects sbi->s_lastblock to be the last
1870  * block on the media.
1871  *
1872  * Return <0 on error, 0 if anchor found. -EAGAIN is special meaning anchor
1873  * was not found.
1874  */
1875 static int udf_find_anchor(struct super_block *sb,
1876 			   struct kernel_lb_addr *fileset)
1877 {
1878 	struct udf_sb_info *sbi = UDF_SB(sb);
1879 	sector_t lastblock = sbi->s_last_block;
1880 	int ret;
1881 
1882 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1883 	if (ret != -EAGAIN)
1884 		goto out;
1885 
1886 	/* No anchor found? Try VARCONV conversion of block numbers */
1887 	UDF_SET_FLAG(sb, UDF_FLAG_VARCONV);
1888 	lastblock = udf_variable_to_fixed(sbi->s_last_block);
1889 	/* Firstly, we try to not convert number of the last block */
1890 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1891 	if (ret != -EAGAIN)
1892 		goto out;
1893 
1894 	lastblock = sbi->s_last_block;
1895 	/* Secondly, we try with converted number of the last block */
1896 	ret = udf_scan_anchors(sb, &lastblock, fileset);
1897 	if (ret < 0) {
1898 		/* VARCONV didn't help. Clear it. */
1899 		UDF_CLEAR_FLAG(sb, UDF_FLAG_VARCONV);
1900 	}
1901 out:
1902 	if (ret == 0)
1903 		sbi->s_last_block = lastblock;
1904 	return ret;
1905 }
1906 
1907 /*
1908  * Check Volume Structure Descriptor, find Anchor block and load Volume
1909  * Descriptor Sequence.
1910  *
1911  * Returns < 0 on error, 0 on success. -EAGAIN is special meaning anchor
1912  * block was not found.
1913  */
1914 static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
1915 			int silent, struct kernel_lb_addr *fileset)
1916 {
1917 	struct udf_sb_info *sbi = UDF_SB(sb);
1918 	loff_t nsr_off;
1919 	int ret;
1920 
1921 	if (!sb_set_blocksize(sb, uopt->blocksize)) {
1922 		if (!silent)
1923 			udf_warn(sb, "Bad block size\n");
1924 		return -EINVAL;
1925 	}
1926 	sbi->s_last_block = uopt->lastblock;
1927 	if (!uopt->novrs) {
1928 		/* Check that it is NSR02 compliant */
1929 		nsr_off = udf_check_vsd(sb);
1930 		if (!nsr_off) {
1931 			if (!silent)
1932 				udf_warn(sb, "No VRS found\n");
1933 			return -EINVAL;
1934 		}
1935 		if (nsr_off == -1)
1936 			udf_debug("Failed to read sector at offset %d. "
1937 				  "Assuming open disc. Skipping validity "
1938 				  "check\n", VSD_FIRST_SECTOR_OFFSET);
1939 		if (!sbi->s_last_block)
1940 			sbi->s_last_block = udf_get_last_block(sb);
1941 	} else {
1942 		udf_debug("Validity check skipped because of novrs option\n");
1943 	}
1944 
1945 	/* Look for anchor block and load Volume Descriptor Sequence */
1946 	sbi->s_anchor = uopt->anchor;
1947 	ret = udf_find_anchor(sb, fileset);
1948 	if (ret < 0) {
1949 		if (!silent && ret == -EAGAIN)
1950 			udf_warn(sb, "No anchor found\n");
1951 		return ret;
1952 	}
1953 	return 0;
1954 }
1955 
1956 static void udf_finalize_lvid(struct logicalVolIntegrityDesc *lvid)
1957 {
1958 	struct timespec64 ts;
1959 
1960 	ktime_get_real_ts64(&ts);
1961 	udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
1962 	lvid->descTag.descCRC = cpu_to_le16(
1963 		crc_itu_t(0, (char *)lvid + sizeof(struct tag),
1964 			le16_to_cpu(lvid->descTag.descCRCLength)));
1965 	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
1966 }
1967 
1968 static void udf_open_lvid(struct super_block *sb)
1969 {
1970 	struct udf_sb_info *sbi = UDF_SB(sb);
1971 	struct buffer_head *bh = sbi->s_lvid_bh;
1972 	struct logicalVolIntegrityDesc *lvid;
1973 	struct logicalVolIntegrityDescImpUse *lvidiu;
1974 
1975 	if (!bh)
1976 		return;
1977 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
1978 	lvidiu = udf_sb_lvidiu(sb);
1979 	if (!lvidiu)
1980 		return;
1981 
1982 	mutex_lock(&sbi->s_alloc_mutex);
1983 	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
1984 	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
1985 	if (le32_to_cpu(lvid->integrityType) == LVID_INTEGRITY_TYPE_CLOSE)
1986 		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
1987 	else
1988 		UDF_SET_FLAG(sb, UDF_FLAG_INCONSISTENT);
1989 
1990 	udf_finalize_lvid(lvid);
1991 	mark_buffer_dirty(bh);
1992 	sbi->s_lvid_dirty = 0;
1993 	mutex_unlock(&sbi->s_alloc_mutex);
1994 	/* Make opening of filesystem visible on the media immediately */
1995 	sync_dirty_buffer(bh);
1996 }
1997 
1998 static void udf_close_lvid(struct super_block *sb)
1999 {
2000 	struct udf_sb_info *sbi = UDF_SB(sb);
2001 	struct buffer_head *bh = sbi->s_lvid_bh;
2002 	struct logicalVolIntegrityDesc *lvid;
2003 	struct logicalVolIntegrityDescImpUse *lvidiu;
2004 
2005 	if (!bh)
2006 		return;
2007 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2008 	lvidiu = udf_sb_lvidiu(sb);
2009 	if (!lvidiu)
2010 		return;
2011 
2012 	mutex_lock(&sbi->s_alloc_mutex);
2013 	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2014 	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2015 	if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
2016 		lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
2017 	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
2018 		lvidiu->minUDFReadRev = cpu_to_le16(sbi->s_udfrev);
2019 	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFWriteRev))
2020 		lvidiu->minUDFWriteRev = cpu_to_le16(sbi->s_udfrev);
2021 	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_INCONSISTENT))
2022 		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);
2023 
2024 	/*
2025 	 * We set buffer uptodate unconditionally here to avoid spurious
2026 	 * warnings from mark_buffer_dirty() when previous EIO has marked
2027 	 * the buffer as !uptodate
2028 	 */
2029 	set_buffer_uptodate(bh);
2030 	udf_finalize_lvid(lvid);
2031 	mark_buffer_dirty(bh);
2032 	sbi->s_lvid_dirty = 0;
2033 	mutex_unlock(&sbi->s_alloc_mutex);
2034 	/* Make closing of filesystem visible on the media immediately */
2035 	sync_dirty_buffer(bh);
2036 }
2037 
2038 u64 lvid_get_unique_id(struct super_block *sb)
2039 {
2040 	struct buffer_head *bh;
2041 	struct udf_sb_info *sbi = UDF_SB(sb);
2042 	struct logicalVolIntegrityDesc *lvid;
2043 	struct logicalVolHeaderDesc *lvhd;
2044 	u64 uniqueID;
2045 	u64 ret;
2046 
2047 	bh = sbi->s_lvid_bh;
2048 	if (!bh)
2049 		return 0;
2050 
2051 	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2052 	lvhd = (struct logicalVolHeaderDesc *)lvid->logicalVolContentsUse;
2053 
2054 	mutex_lock(&sbi->s_alloc_mutex);
2055 	ret = uniqueID = le64_to_cpu(lvhd->uniqueID);
2056 	if (!(++uniqueID & 0xFFFFFFFF))
2057 		uniqueID += 16;
2058 	lvhd->uniqueID = cpu_to_le64(uniqueID);
2059 	udf_updated_lvid(sb);
2060 	mutex_unlock(&sbi->s_alloc_mutex);
2061 
2062 	return ret;
2063 }
2064 
2065 static int udf_fill_super(struct super_block *sb, void *options, int silent)
2066 {
2067 	int ret = -EINVAL;
2068 	struct inode *inode = NULL;
2069 	struct udf_options uopt;
2070 	struct kernel_lb_addr rootdir, fileset;
2071 	struct udf_sb_info *sbi;
2072 	bool lvid_open = false;
2073 
2074 	uopt.flags = (1 << UDF_FLAG_USE_AD_IN_ICB) | (1 << UDF_FLAG_STRICT);
2075 	/* By default we'll use overflow[ug]id when UDF inode [ug]id == -1 */
2076 	uopt.uid = make_kuid(current_user_ns(), overflowuid);
2077 	uopt.gid = make_kgid(current_user_ns(), overflowgid);
2078 	uopt.umask = 0;
2079 	uopt.fmode = UDF_INVALID_MODE;
2080 	uopt.dmode = UDF_INVALID_MODE;
2081 	uopt.nls_map = NULL;
2082 
2083 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2084 	if (!sbi)
2085 		return -ENOMEM;
2086 
2087 	sb->s_fs_info = sbi;
2088 
2089 	mutex_init(&sbi->s_alloc_mutex);
2090 
2091 	if (!udf_parse_options((char *)options, &uopt, false))
2092 		goto parse_options_failure;
2093 
2094 	if (uopt.flags & (1 << UDF_FLAG_UTF8) &&
2095 	    uopt.flags & (1 << UDF_FLAG_NLS_MAP)) {
2096 		udf_err(sb, "utf8 cannot be combined with iocharset\n");
2097 		goto parse_options_failure;
2098 	}
2099 	if ((uopt.flags & (1 << UDF_FLAG_NLS_MAP)) && !uopt.nls_map) {
2100 		uopt.nls_map = load_nls_default();
2101 		if (!uopt.nls_map)
2102 			uopt.flags &= ~(1 << UDF_FLAG_NLS_MAP);
2103 		else
2104 			udf_debug("Using default NLS map\n");
2105 	}
2106 	if (!(uopt.flags & (1 << UDF_FLAG_NLS_MAP)))
2107 		uopt.flags |= (1 << UDF_FLAG_UTF8);
2108 
2109 	fileset.logicalBlockNum = 0xFFFFFFFF;
2110 	fileset.partitionReferenceNum = 0xFFFF;
2111 
2112 	sbi->s_flags = uopt.flags;
2113 	sbi->s_uid = uopt.uid;
2114 	sbi->s_gid = uopt.gid;
2115 	sbi->s_umask = uopt.umask;
2116 	sbi->s_fmode = uopt.fmode;
2117 	sbi->s_dmode = uopt.dmode;
2118 	sbi->s_nls_map = uopt.nls_map;
2119 	rwlock_init(&sbi->s_cred_lock);
2120 
2121 	if (uopt.session == 0xFFFFFFFF)
2122 		sbi->s_session = udf_get_last_session(sb);
2123 	else
2124 		sbi->s_session = uopt.session;
2125 
2126 	udf_debug("Multi-session=%d\n", sbi->s_session);
2127 
2128 	/* Fill in the rest of the superblock */
2129 	sb->s_op = &udf_sb_ops;
2130 	sb->s_export_op = &udf_export_ops;
2131 
2132 	sb->s_magic = UDF_SUPER_MAGIC;
2133 	sb->s_time_gran = 1000;
2134 
2135 	if (uopt.flags & (1 << UDF_FLAG_BLOCKSIZE_SET)) {
2136 		ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2137 	} else {
2138 		uopt.blocksize = bdev_logical_block_size(sb->s_bdev);
2139 		while (uopt.blocksize <= 4096) {
2140 			ret = udf_load_vrs(sb, &uopt, silent, &fileset);
2141 			if (ret < 0) {
2142 				if (!silent && ret != -EACCES) {
2143 					pr_notice("Scanning with blocksize %u failed\n",
2144 						  uopt.blocksize);
2145 				}
2146 				brelse(sbi->s_lvid_bh);
2147 				sbi->s_lvid_bh = NULL;
2148 				/*
2149 				 * EACCES is special - we want to propagate to
2150 				 * upper layers that we cannot handle RW mount.
2151 				 */
2152 				if (ret == -EACCES)
2153 					break;
2154 			} else
2155 				break;
2156 
2157 			uopt.blocksize <<= 1;
2158 		}
2159 	}
2160 	if (ret < 0) {
2161 		if (ret == -EAGAIN) {
2162 			udf_warn(sb, "No partition found (1)\n");
2163 			ret = -EINVAL;
2164 		}
2165 		goto error_out;
2166 	}
2167 
2168 	udf_debug("Lastblock=%u\n", sbi->s_last_block);
2169 
2170 	if (sbi->s_lvid_bh) {
2171 		struct logicalVolIntegrityDescImpUse *lvidiu =
2172 							udf_sb_lvidiu(sb);
2173 		uint16_t minUDFReadRev;
2174 		uint16_t minUDFWriteRev;
2175 
2176 		if (!lvidiu) {
2177 			ret = -EINVAL;
2178 			goto error_out;
2179 		}
2180 		minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev);
2181 		minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev);
2182 		if (minUDFReadRev > UDF_MAX_READ_VERSION) {
2183 			udf_err(sb, "minUDFReadRev=%x (max is %x)\n",
2184 				minUDFReadRev,
2185 				UDF_MAX_READ_VERSION);
2186 			ret = -EINVAL;
2187 			goto error_out;
2188 		} else if (minUDFWriteRev > UDF_MAX_WRITE_VERSION) {
2189 			if (!sb_rdonly(sb)) {
2190 				ret = -EACCES;
2191 				goto error_out;
2192 			}
2193 			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2194 		}
2195 
2196 		sbi->s_udfrev = minUDFWriteRev;
2197 
2198 		if (minUDFReadRev >= UDF_VERS_USE_EXTENDED_FE)
2199 			UDF_SET_FLAG(sb, UDF_FLAG_USE_EXTENDED_FE);
2200 		if (minUDFReadRev >= UDF_VERS_USE_STREAMS)
2201 			UDF_SET_FLAG(sb, UDF_FLAG_USE_STREAMS);
2202 	}
2203 
2204 	if (!sbi->s_partitions) {
2205 		udf_warn(sb, "No partition found (2)\n");
2206 		ret = -EINVAL;
2207 		goto error_out;
2208 	}
2209 
2210 	if (sbi->s_partmaps[sbi->s_partition].s_partition_flags &
2211 			UDF_PART_FLAG_READ_ONLY) {
2212 		if (!sb_rdonly(sb)) {
2213 			ret = -EACCES;
2214 			goto error_out;
2215 		}
2216 		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2217 	}
2218 
2219 	if (udf_find_fileset(sb, &fileset, &rootdir)) {
2220 		udf_warn(sb, "No fileset found\n");
2221 		ret = -EINVAL;
2222 		goto error_out;
2223 	}
2224 
2225 	if (!silent) {
2226 		struct timestamp ts;
2227 		udf_time_to_disk_stamp(&ts, sbi->s_record_time);
2228 		udf_info("Mounting volume '%s', timestamp %04u/%02u/%02u %02u:%02u (%x)\n",
2229 			 sbi->s_volume_ident,
2230 			 le16_to_cpu(ts.year), ts.month, ts.day,
2231 			 ts.hour, ts.minute, le16_to_cpu(ts.typeAndTimezone));
2232 	}
2233 	if (!sb_rdonly(sb)) {
2234 		udf_open_lvid(sb);
2235 		lvid_open = true;
2236 	}
2237 
2238 	/* Assign the root inode */
2239 	/* assign inodes by physical block number */
2240 	/* perhaps it's not extensible enough, but for now ... */
2241 	inode = udf_iget(sb, &rootdir);
2242 	if (IS_ERR(inode)) {
2243 		udf_err(sb, "Error in udf_iget, block=%u, partition=%u\n",
2244 		       rootdir.logicalBlockNum, rootdir.partitionReferenceNum);
2245 		ret = PTR_ERR(inode);
2246 		goto error_out;
2247 	}
2248 
2249 	/* Allocate a dentry for the root inode */
2250 	sb->s_root = d_make_root(inode);
2251 	if (!sb->s_root) {
2252 		udf_err(sb, "Couldn't allocate root dentry\n");
2253 		ret = -ENOMEM;
2254 		goto error_out;
2255 	}
2256 	sb->s_maxbytes = MAX_LFS_FILESIZE;
2257 	sb->s_max_links = UDF_MAX_LINKS;
2258 	return 0;
2259 
2260 error_out:
2261 	iput(sbi->s_vat_inode);
2262 parse_options_failure:
2263 	if (uopt.nls_map)
2264 		unload_nls(uopt.nls_map);
2265 	if (lvid_open)
2266 		udf_close_lvid(sb);
2267 	brelse(sbi->s_lvid_bh);
2268 	udf_sb_free_partitions(sb);
2269 	kfree(sbi);
2270 	sb->s_fs_info = NULL;
2271 
2272 	return ret;
2273 }
2274 
2275 void _udf_err(struct super_block *sb, const char *function,
2276 	      const char *fmt, ...)
2277 {
2278 	struct va_format vaf;
2279 	va_list args;
2280 
2281 	va_start(args, fmt);
2282 
2283 	vaf.fmt = fmt;
2284 	vaf.va = &args;
2285 
2286 	pr_err("error (device %s): %s: %pV", sb->s_id, function, &vaf);
2287 
2288 	va_end(args);
2289 }
2290 
2291 void _udf_warn(struct super_block *sb, const char *function,
2292 	       const char *fmt, ...)
2293 {
2294 	struct va_format vaf;
2295 	va_list args;
2296 
2297 	va_start(args, fmt);
2298 
2299 	vaf.fmt = fmt;
2300 	vaf.va = &args;
2301 
2302 	pr_warn("warning (device %s): %s: %pV", sb->s_id, function, &vaf);
2303 
2304 	va_end(args);
2305 }
2306 
2307 static void udf_put_super(struct super_block *sb)
2308 {
2309 	struct udf_sb_info *sbi;
2310 
2311 	sbi = UDF_SB(sb);
2312 
2313 	iput(sbi->s_vat_inode);
2314 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
2315 		unload_nls(sbi->s_nls_map);
2316 	if (!sb_rdonly(sb))
2317 		udf_close_lvid(sb);
2318 	brelse(sbi->s_lvid_bh);
2319 	udf_sb_free_partitions(sb);
2320 	mutex_destroy(&sbi->s_alloc_mutex);
2321 	kfree(sb->s_fs_info);
2322 	sb->s_fs_info = NULL;
2323 }
2324 
2325 static int udf_sync_fs(struct super_block *sb, int wait)
2326 {
2327 	struct udf_sb_info *sbi = UDF_SB(sb);
2328 
2329 	mutex_lock(&sbi->s_alloc_mutex);
2330 	if (sbi->s_lvid_dirty) {
2331 		struct buffer_head *bh = sbi->s_lvid_bh;
2332 		struct logicalVolIntegrityDesc *lvid;
2333 
2334 		lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2335 		udf_finalize_lvid(lvid);
2336 
2337 		/*
2338 		 * Blockdevice will be synced later so we don't have to submit
2339 		 * the buffer for IO
2340 		 */
2341 		mark_buffer_dirty(bh);
2342 		sbi->s_lvid_dirty = 0;
2343 	}
2344 	mutex_unlock(&sbi->s_alloc_mutex);
2345 
2346 	return 0;
2347 }
2348 
2349 static int udf_statfs(struct dentry *dentry, struct kstatfs *buf)
2350 {
2351 	struct super_block *sb = dentry->d_sb;
2352 	struct udf_sb_info *sbi = UDF_SB(sb);
2353 	struct logicalVolIntegrityDescImpUse *lvidiu;
2354 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
2355 
2356 	lvidiu = udf_sb_lvidiu(sb);
2357 	buf->f_type = UDF_SUPER_MAGIC;
2358 	buf->f_bsize = sb->s_blocksize;
2359 	buf->f_blocks = sbi->s_partmaps[sbi->s_partition].s_partition_len;
2360 	buf->f_bfree = udf_count_free(sb);
2361 	buf->f_bavail = buf->f_bfree;
2362 	buf->f_files = (lvidiu != NULL ? (le32_to_cpu(lvidiu->numFiles) +
2363 					  le32_to_cpu(lvidiu->numDirs)) : 0)
2364 			+ buf->f_bfree;
2365 	buf->f_ffree = buf->f_bfree;
2366 	buf->f_namelen = UDF_NAME_LEN;
2367 	buf->f_fsid.val[0] = (u32)id;
2368 	buf->f_fsid.val[1] = (u32)(id >> 32);
2369 
2370 	return 0;
2371 }
2372 
2373 static unsigned int udf_count_free_bitmap(struct super_block *sb,
2374 					  struct udf_bitmap *bitmap)
2375 {
2376 	struct buffer_head *bh = NULL;
2377 	unsigned int accum = 0;
2378 	int index;
2379 	udf_pblk_t block = 0, newblock;
2380 	struct kernel_lb_addr loc;
2381 	uint32_t bytes;
2382 	uint8_t *ptr;
2383 	uint16_t ident;
2384 	struct spaceBitmapDesc *bm;
2385 
2386 	loc.logicalBlockNum = bitmap->s_extPosition;
2387 	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
2388 	bh = udf_read_ptagged(sb, &loc, 0, &ident);
2389 
2390 	if (!bh) {
2391 		udf_err(sb, "udf_count_free failed\n");
2392 		goto out;
2393 	} else if (ident != TAG_IDENT_SBD) {
2394 		brelse(bh);
2395 		udf_err(sb, "udf_count_free failed\n");
2396 		goto out;
2397 	}
2398 
2399 	bm = (struct spaceBitmapDesc *)bh->b_data;
2400 	bytes = le32_to_cpu(bm->numOfBytes);
2401 	index = sizeof(struct spaceBitmapDesc); /* offset in first block only */
2402 	ptr = (uint8_t *)bh->b_data;
2403 
2404 	while (bytes > 0) {
2405 		u32 cur_bytes = min_t(u32, bytes, sb->s_blocksize - index);
2406 		accum += bitmap_weight((const unsigned long *)(ptr + index),
2407 					cur_bytes * 8);
2408 		bytes -= cur_bytes;
2409 		if (bytes) {
2410 			brelse(bh);
2411 			newblock = udf_get_lb_pblock(sb, &loc, ++block);
2412 			bh = udf_tread(sb, newblock);
2413 			if (!bh) {
2414 				udf_debug("read failed\n");
2415 				goto out;
2416 			}
2417 			index = 0;
2418 			ptr = (uint8_t *)bh->b_data;
2419 		}
2420 	}
2421 	brelse(bh);
2422 out:
2423 	return accum;
2424 }
2425 
2426 static unsigned int udf_count_free_table(struct super_block *sb,
2427 					 struct inode *table)
2428 {
2429 	unsigned int accum = 0;
2430 	uint32_t elen;
2431 	struct kernel_lb_addr eloc;
2432 	int8_t etype;
2433 	struct extent_position epos;
2434 
2435 	mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
2436 	epos.block = UDF_I(table)->i_location;
2437 	epos.offset = sizeof(struct unallocSpaceEntry);
2438 	epos.bh = NULL;
2439 
2440 	while ((etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1)
2441 		accum += (elen >> table->i_sb->s_blocksize_bits);
2442 
2443 	brelse(epos.bh);
2444 	mutex_unlock(&UDF_SB(sb)->s_alloc_mutex);
2445 
2446 	return accum;
2447 }
2448 
2449 static unsigned int udf_count_free(struct super_block *sb)
2450 {
2451 	unsigned int accum = 0;
2452 	struct udf_sb_info *sbi;
2453 	struct udf_part_map *map;
2454 
2455 	sbi = UDF_SB(sb);
2456 	if (sbi->s_lvid_bh) {
2457 		struct logicalVolIntegrityDesc *lvid =
2458 			(struct logicalVolIntegrityDesc *)
2459 			sbi->s_lvid_bh->b_data;
2460 		if (le32_to_cpu(lvid->numOfPartitions) > sbi->s_partition) {
2461 			accum = le32_to_cpu(
2462 					lvid->freeSpaceTable[sbi->s_partition]);
2463 			if (accum == 0xFFFFFFFF)
2464 				accum = 0;
2465 		}
2466 	}
2467 
2468 	if (accum)
2469 		return accum;
2470 
2471 	map = &sbi->s_partmaps[sbi->s_partition];
2472 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
2473 		accum += udf_count_free_bitmap(sb,
2474 					       map->s_uspace.s_bitmap);
2475 	}
2476 	if (accum)
2477 		return accum;
2478 
2479 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
2480 		accum += udf_count_free_table(sb,
2481 					      map->s_uspace.s_table);
2482 	}
2483 	return accum;
2484 }
2485 
2486 MODULE_AUTHOR("Ben Fennema");
2487 MODULE_DESCRIPTION("Universal Disk Format Filesystem");
2488 MODULE_LICENSE("GPL");
2489 module_init(init_udf_fs)
2490 module_exit(exit_udf_fs)
2491