1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * super.c
   4 *
   5 * PURPOSE
   6 *  Super block routines for the OSTA-UDF(tm) filesystem.
   7 *
   8 * DESCRIPTION
   9 *  OSTA-UDF(tm) = Optical Storage Technology Association
  10 *  Universal Disk Format.
  11 *
  12 *  This code is based on version 2.00 of the UDF specification,
  13 *  and revision 3 of the ECMA 167 standard [equivalent to ISO 13346].
  14 *    http://www.osta.org/
  15 *    https://www.ecma.ch/
  16 *    https://www.iso.org/
  17 *
  18 * COPYRIGHT
  19 *  (C) 1998 Dave Boynton
  20 *  (C) 1998-2004 Ben Fennema
  21 *  (C) 2000 Stelias Computing Inc
  22 *
  23 * HISTORY
  24 *
  25 *  09/24/98 dgb  changed to allow compiling outside of kernel, and
  26 *                added some debugging.
  27 *  10/01/98 dgb  updated to allow (some) possibility of compiling w/2.0.34
  28 *  10/16/98      attempting some multi-session support
  29 *  10/17/98      added freespace count for "df"
  30 *  11/11/98 gr   added novrs option
  31 *  11/26/98 dgb  added fileset,anchor mount options
  32 *  12/06/98 blf  really hosed things royally. vat/sparing support. sequenced
  33 *                vol descs. rewrote option handling based on isofs
  34 *  12/20/98      find the free space bitmap (if it exists)
  35 */
  36
  37#include "udfdecl.h"
  38
  39#include <linux/blkdev.h>
  40#include <linux/slab.h>
  41#include <linux/kernel.h>
  42#include <linux/module.h>
  43#include <linux/stat.h>
  44#include <linux/cdrom.h>
  45#include <linux/nls.h>
  46#include <linux/vfs.h>
  47#include <linux/vmalloc.h>
  48#include <linux/errno.h>
  49#include <linux/seq_file.h>
  50#include <linux/bitmap.h>
  51#include <linux/crc-itu-t.h>
  52#include <linux/log2.h>
  53#include <asm/byteorder.h>
  54#include <linux/iversion.h>
  55#include <linux/fs_context.h>
  56#include <linux/fs_parser.h>
  57
  58#include "udf_sb.h"
  59#include "udf_i.h"
  60
  61#include <linux/init.h>
  62#include <linux/uaccess.h>
  63
  64enum {
  65	VDS_POS_PRIMARY_VOL_DESC,
  66	VDS_POS_UNALLOC_SPACE_DESC,
  67	VDS_POS_LOGICAL_VOL_DESC,
  68	VDS_POS_IMP_USE_VOL_DESC,
  69	VDS_POS_LENGTH
  70};
  71
  72#define VSD_FIRST_SECTOR_OFFSET		32768
  73#define VSD_MAX_SECTOR_OFFSET		0x800000
  74
  75/*
  76 * Maximum number of Terminating Descriptor / Logical Volume Integrity
  77 * Descriptor redirections. The chosen numbers are arbitrary - just that we
  78 * hopefully don't limit any real use of rewritten inode on write-once media
  79 * but avoid looping for too long on corrupted media.
  80 */
  81#define UDF_MAX_TD_NESTING 64
  82#define UDF_MAX_LVID_NESTING 1000
  83
  84enum { UDF_MAX_LINKS = 0xffff };
  85/*
  86 * We limit filesize to 4TB. This is arbitrary as the on-disk format supports
  87 * more but because the file space is described by a linked list of extents,
  88 * each of which can have at most 1GB, the creation and handling of extents
  89 * gets unusably slow beyond certain point...
  90 */
  91#define UDF_MAX_FILESIZE (1ULL << 42)
  92
  93/* These are the "meat" - everything else is stuffing */
  94static int udf_fill_super(struct super_block *sb, struct fs_context *fc);
  95static void udf_put_super(struct super_block *);
  96static int udf_sync_fs(struct super_block *, int);
  97static void udf_load_logicalvolint(struct super_block *, struct kernel_extent_ad);
  98static void udf_open_lvid(struct super_block *);
  99static void udf_close_lvid(struct super_block *);
 100static unsigned int udf_count_free(struct super_block *);
 101static int udf_statfs(struct dentry *, struct kstatfs *);
 102static int udf_show_options(struct seq_file *, struct dentry *);
 103static int udf_init_fs_context(struct fs_context *fc);
 104static int udf_parse_param(struct fs_context *fc, struct fs_parameter *param);
 105static int udf_reconfigure(struct fs_context *fc);
 106static void udf_free_fc(struct fs_context *fc);
 107static const struct fs_parameter_spec udf_param_spec[];
 108
 109struct logicalVolIntegrityDescImpUse *udf_sb_lvidiu(struct super_block *sb)
 110{
 111	struct logicalVolIntegrityDesc *lvid;
 112	unsigned int partnum;
 113	unsigned int offset;
 114
 115	if (!UDF_SB(sb)->s_lvid_bh)
 116		return NULL;
 117	lvid = (struct logicalVolIntegrityDesc *)UDF_SB(sb)->s_lvid_bh->b_data;
 118	partnum = le32_to_cpu(lvid->numOfPartitions);
 119	/* The offset is to skip freeSpaceTable and sizeTable arrays */
 120	offset = partnum * 2 * sizeof(uint32_t);
 121	return (struct logicalVolIntegrityDescImpUse *)
 122					(((uint8_t *)(lvid + 1)) + offset);
 123}
 124
 125/* UDF filesystem type */
 126static int udf_get_tree(struct fs_context *fc)
 127{
 128	return get_tree_bdev(fc, udf_fill_super);
 129}
 130
 131static const struct fs_context_operations udf_context_ops = {
 132	.parse_param	= udf_parse_param,
 133	.get_tree	= udf_get_tree,
 134	.reconfigure	= udf_reconfigure,
 135	.free		= udf_free_fc,
 136};
 137
 138static struct file_system_type udf_fstype = {
 139	.owner		= THIS_MODULE,
 140	.name		= "udf",
 141	.kill_sb	= kill_block_super,
 142	.fs_flags	= FS_REQUIRES_DEV,
 143	.init_fs_context = udf_init_fs_context,
 144	.parameters	= udf_param_spec,
 145};
 146MODULE_ALIAS_FS("udf");
 147
 148static struct kmem_cache *udf_inode_cachep;
 149
 150static struct inode *udf_alloc_inode(struct super_block *sb)
 151{
 152	struct udf_inode_info *ei;
 153	ei = alloc_inode_sb(sb, udf_inode_cachep, GFP_KERNEL);
 154	if (!ei)
 155		return NULL;
 156
 157	ei->i_unique = 0;
 158	ei->i_lenExtents = 0;
 159	ei->i_lenStreams = 0;
 160	ei->i_next_alloc_block = 0;
 161	ei->i_next_alloc_goal = 0;
 162	ei->i_strat4096 = 0;
 163	ei->i_streamdir = 0;
 164	ei->i_hidden = 0;
 165	init_rwsem(&ei->i_data_sem);
 166	ei->cached_extent.lstart = -1;
 167	spin_lock_init(&ei->i_extent_cache_lock);
 168	inode_set_iversion(&ei->vfs_inode, 1);
 169
 170	return &ei->vfs_inode;
 171}
 172
 173static void udf_free_in_core_inode(struct inode *inode)
 174{
 175	kmem_cache_free(udf_inode_cachep, UDF_I(inode));
 176}
 177
 178static void init_once(void *foo)
 179{
 180	struct udf_inode_info *ei = foo;
 181
 182	ei->i_data = NULL;
 183	inode_init_once(&ei->vfs_inode);
 184}
 185
 186static int __init init_inodecache(void)
 187{
 188	udf_inode_cachep = kmem_cache_create("udf_inode_cache",
 189					     sizeof(struct udf_inode_info),
 190					     0, (SLAB_RECLAIM_ACCOUNT |
 191						 SLAB_ACCOUNT),
 192					     init_once);
 193	if (!udf_inode_cachep)
 194		return -ENOMEM;
 195	return 0;
 196}
 197
 198static void destroy_inodecache(void)
 199{
 200	/*
 201	 * Make sure all delayed rcu free inodes are flushed before we
 202	 * destroy cache.
 203	 */
 204	rcu_barrier();
 205	kmem_cache_destroy(udf_inode_cachep);
 206}
 207
 208/* Superblock operations */
 209static const struct super_operations udf_sb_ops = {
 210	.alloc_inode	= udf_alloc_inode,
 211	.free_inode	= udf_free_in_core_inode,
 212	.write_inode	= udf_write_inode,
 213	.evict_inode	= udf_evict_inode,
 214	.put_super	= udf_put_super,
 215	.sync_fs	= udf_sync_fs,
 216	.statfs		= udf_statfs,
 217	.show_options	= udf_show_options,
 218};
 219
 220struct udf_options {
 221	unsigned int blocksize;
 222	unsigned int session;
 223	unsigned int lastblock;
 224	unsigned int anchor;
 225	unsigned int flags;
 226	umode_t umask;
 227	kgid_t gid;
 228	kuid_t uid;
 229	umode_t fmode;
 230	umode_t dmode;
 231	struct nls_table *nls_map;
 232};
 233
 234/*
 235 * UDF has historically preserved prior mount options across
 236 * a remount, so copy those here if remounting, otherwise set
 237 * initial mount defaults.
 238 */
 239static void udf_init_options(struct fs_context *fc, struct udf_options *uopt)
 240{
 241	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
 242		struct super_block *sb = fc->root->d_sb;
 243		struct udf_sb_info *sbi = UDF_SB(sb);
 244
 245		uopt->flags = sbi->s_flags;
 246		uopt->uid   = sbi->s_uid;
 247		uopt->gid   = sbi->s_gid;
 248		uopt->umask = sbi->s_umask;
 249		uopt->fmode = sbi->s_fmode;
 250		uopt->dmode = sbi->s_dmode;
 251		uopt->nls_map = NULL;
 252	} else {
 253		uopt->flags = (1 << UDF_FLAG_USE_AD_IN_ICB) |
 254			      (1 << UDF_FLAG_STRICT);
 255		/*
 256		 * By default we'll use overflow[ug]id when UDF
 257		 * inode [ug]id == -1
 258		 */
 259		uopt->uid = make_kuid(current_user_ns(), overflowuid);
 260		uopt->gid = make_kgid(current_user_ns(), overflowgid);
 261		uopt->umask = 0;
 262		uopt->fmode = UDF_INVALID_MODE;
 263		uopt->dmode = UDF_INVALID_MODE;
 264		uopt->nls_map = NULL;
 265		uopt->session = 0xFFFFFFFF;
 266	}
 267}
 268
 269static int udf_init_fs_context(struct fs_context *fc)
 270{
 271	struct udf_options *uopt;
 272
 273	uopt = kzalloc(sizeof(*uopt), GFP_KERNEL);
 274	if (!uopt)
 275		return -ENOMEM;
 276
 277	udf_init_options(fc, uopt);
 278
 279	fc->fs_private = uopt;
 280	fc->ops = &udf_context_ops;
 281
 282	return 0;
 283}
 284
 285static void udf_free_fc(struct fs_context *fc)
 286{
 287	struct udf_options *uopt = fc->fs_private;
 288
 289	unload_nls(uopt->nls_map);
 290	kfree(fc->fs_private);
 291}
 292
 293static int __init init_udf_fs(void)
 294{
 295	int err;
 296
 297	err = init_inodecache();
 298	if (err)
 299		goto out1;
 300	err = register_filesystem(&udf_fstype);
 301	if (err)
 302		goto out;
 303
 304	return 0;
 305
 306out:
 307	destroy_inodecache();
 308
 309out1:
 310	return err;
 311}
 312
 313static void __exit exit_udf_fs(void)
 314{
 315	unregister_filesystem(&udf_fstype);
 316	destroy_inodecache();
 317}
 318
 319static int udf_sb_alloc_partition_maps(struct super_block *sb, u32 count)
 320{
 321	struct udf_sb_info *sbi = UDF_SB(sb);
 322
 323	sbi->s_partmaps = kcalloc(count, sizeof(*sbi->s_partmaps), GFP_KERNEL);
 324	if (!sbi->s_partmaps) {
 325		sbi->s_partitions = 0;
 326		return -ENOMEM;
 327	}
 328
 329	sbi->s_partitions = count;
 330	return 0;
 331}
 332
 333static void udf_sb_free_bitmap(struct udf_bitmap *bitmap)
 334{
 335	int i;
 336	int nr_groups = bitmap->s_nr_groups;
 337
 338	for (i = 0; i < nr_groups; i++)
 339		if (!IS_ERR_OR_NULL(bitmap->s_block_bitmap[i]))
 340			brelse(bitmap->s_block_bitmap[i]);
 341
 342	kvfree(bitmap);
 343}
 344
 345static void udf_free_partition(struct udf_part_map *map)
 346{
 347	int i;
 348	struct udf_meta_data *mdata;
 349
 350	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
 351		iput(map->s_uspace.s_table);
 352	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
 353		udf_sb_free_bitmap(map->s_uspace.s_bitmap);
 354	if (map->s_partition_type == UDF_SPARABLE_MAP15)
 355		for (i = 0; i < 4; i++)
 356			brelse(map->s_type_specific.s_sparing.s_spar_map[i]);
 357	else if (map->s_partition_type == UDF_METADATA_MAP25) {
 358		mdata = &map->s_type_specific.s_metadata;
 359		iput(mdata->s_metadata_fe);
 360		mdata->s_metadata_fe = NULL;
 361
 362		iput(mdata->s_mirror_fe);
 363		mdata->s_mirror_fe = NULL;
 364
 365		iput(mdata->s_bitmap_fe);
 366		mdata->s_bitmap_fe = NULL;
 367	}
 368}
 369
 370static void udf_sb_free_partitions(struct super_block *sb)
 371{
 372	struct udf_sb_info *sbi = UDF_SB(sb);
 373	int i;
 374
 375	if (!sbi->s_partmaps)
 376		return;
 377	for (i = 0; i < sbi->s_partitions; i++)
 378		udf_free_partition(&sbi->s_partmaps[i]);
 379	kfree(sbi->s_partmaps);
 380	sbi->s_partmaps = NULL;
 381}
 382
 383static int udf_show_options(struct seq_file *seq, struct dentry *root)
 384{
 385	struct super_block *sb = root->d_sb;
 386	struct udf_sb_info *sbi = UDF_SB(sb);
 387
 388	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT))
 389		seq_puts(seq, ",nostrict");
 390	if (UDF_QUERY_FLAG(sb, UDF_FLAG_BLOCKSIZE_SET))
 391		seq_printf(seq, ",bs=%lu", sb->s_blocksize);
 392	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
 393		seq_puts(seq, ",unhide");
 394	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
 395		seq_puts(seq, ",undelete");
 396	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_USE_AD_IN_ICB))
 397		seq_puts(seq, ",noadinicb");
 398	if (UDF_QUERY_FLAG(sb, UDF_FLAG_USE_SHORT_AD))
 399		seq_puts(seq, ",shortad");
 400	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_FORGET))
 401		seq_puts(seq, ",uid=forget");
 402	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_FORGET))
 403		seq_puts(seq, ",gid=forget");
 404	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET))
 405		seq_printf(seq, ",uid=%u", from_kuid(&init_user_ns, sbi->s_uid));
 406	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET))
 407		seq_printf(seq, ",gid=%u", from_kgid(&init_user_ns, sbi->s_gid));
 408	if (sbi->s_umask != 0)
 409		seq_printf(seq, ",umask=%ho", sbi->s_umask);
 410	if (sbi->s_fmode != UDF_INVALID_MODE)
 411		seq_printf(seq, ",mode=%ho", sbi->s_fmode);
 412	if (sbi->s_dmode != UDF_INVALID_MODE)
 413		seq_printf(seq, ",dmode=%ho", sbi->s_dmode);
 414	if (UDF_QUERY_FLAG(sb, UDF_FLAG_SESSION_SET))
 415		seq_printf(seq, ",session=%d", sbi->s_session);
 416	if (UDF_QUERY_FLAG(sb, UDF_FLAG_LASTBLOCK_SET))
 417		seq_printf(seq, ",lastblock=%u", sbi->s_last_block);
 418	if (sbi->s_anchor != 0)
 419		seq_printf(seq, ",anchor=%u", sbi->s_anchor);
 420	if (sbi->s_nls_map)
 421		seq_printf(seq, ",iocharset=%s", sbi->s_nls_map->charset);
 422	else
 423		seq_puts(seq, ",iocharset=utf8");
 424
 425	return 0;
 426}
 427
 428/*
 429 * udf_parse_param
 430 *
 431 * PURPOSE
 432 *	Parse mount options.
 433 *
 434 * DESCRIPTION
 435 *	The following mount options are supported:
 436 *
 437 *	gid=		Set the default group.
 438 *	umask=		Set the default umask.
 439 *	mode=		Set the default file permissions.
 440 *	dmode=		Set the default directory permissions.
 441 *	uid=		Set the default user.
 442 *	bs=		Set the block size.
 443 *	unhide		Show otherwise hidden files.
 444 *	undelete	Show deleted files in lists.
 445 *	adinicb		Embed data in the inode (default)
 446 *	noadinicb	Don't embed data in the inode
 447 *	shortad		Use short ad's
 448 *	longad		Use long ad's (default)
 449 *	nostrict	Unset strict conformance
 450 *	iocharset=	Set the NLS character set
 451 *
 452 *	The remaining are for debugging and disaster recovery:
 453 *
 454 *	novrs		Skip volume sequence recognition
 455 *
 456 *	The following expect a offset from 0.
 457 *
 458 *	session=	Set the CDROM session (default= last session)
 459 *	anchor=		Override standard anchor location. (default= 256)
 460 *	volume=		Override the VolumeDesc location. (unused)
 461 *	partition=	Override the PartitionDesc location. (unused)
 462 *	lastblock=	Set the last block of the filesystem/
 463 *
 464 *	The following expect a offset from the partition root.
 465 *
 466 *	fileset=	Override the fileset block location. (unused)
 467 *	rootdir=	Override the root directory location. (unused)
 468 *		WARNING: overriding the rootdir to a non-directory may
 469 *		yield highly unpredictable results.
 470 *
 471 * PRE-CONDITIONS
 472 *	fc		fs_context with pointer to mount options variable.
 473 *	param		Pointer to fs_parameter being parsed.
 474 *
 475 * POST-CONDITIONS
 476 *	<return>	0	Mount options parsed okay.
 477 *	<return>	errno	Error parsing mount options.
 478 *
 479 * HISTORY
 480 *	July 1, 1997 - Andrew E. Mileski
 481 *	Written, tested, and released.
 482 */
 483
 484enum {
 485	Opt_novrs, Opt_nostrict, Opt_bs, Opt_unhide, Opt_undelete,
 486	Opt_noadinicb, Opt_adinicb, Opt_shortad, Opt_longad,
 487	Opt_gid, Opt_uid, Opt_umask, Opt_session, Opt_lastblock,
 488	Opt_anchor, Opt_volume, Opt_partition, Opt_fileset,
 489	Opt_rootdir, Opt_utf8, Opt_iocharset, Opt_err, Opt_fmode, Opt_dmode
 490};
 491
 492static const struct fs_parameter_spec udf_param_spec[] = {
 493	fsparam_flag	("novrs",		Opt_novrs),
 494	fsparam_flag	("nostrict",		Opt_nostrict),
 495	fsparam_u32	("bs",			Opt_bs),
 496	fsparam_flag	("unhide",		Opt_unhide),
 497	fsparam_flag	("undelete",		Opt_undelete),
 498	fsparam_flag_no	("adinicb",		Opt_adinicb),
 499	fsparam_flag	("shortad",		Opt_shortad),
 500	fsparam_flag	("longad",		Opt_longad),
 501	fsparam_string	("gid",			Opt_gid),
 502	fsparam_string	("uid",			Opt_uid),
 503	fsparam_u32	("umask",		Opt_umask),
 504	fsparam_u32	("session",		Opt_session),
 505	fsparam_u32	("lastblock",		Opt_lastblock),
 506	fsparam_u32	("anchor",		Opt_anchor),
 507	fsparam_u32	("volume",		Opt_volume),
 508	fsparam_u32	("partition",		Opt_partition),
 509	fsparam_u32	("fileset",		Opt_fileset),
 510	fsparam_u32	("rootdir",		Opt_rootdir),
 511	fsparam_flag	("utf8",		Opt_utf8),
 512	fsparam_string	("iocharset",		Opt_iocharset),
 513	fsparam_u32	("mode",		Opt_fmode),
 514	fsparam_u32	("dmode",		Opt_dmode),
 515	{}
 516 };
 517
 518static int udf_parse_param(struct fs_context *fc, struct fs_parameter *param)
 519{
 520	unsigned int uv;
 521	unsigned int n;
 522	struct udf_options *uopt = fc->fs_private;
 523	struct fs_parse_result result;
 524	int token;
 525	bool remount = (fc->purpose & FS_CONTEXT_FOR_RECONFIGURE);
 526
 527	token = fs_parse(fc, udf_param_spec, param, &result);
 528	if (token < 0)
 529		return token;
 530
 531	switch (token) {
 532	case Opt_novrs:
 533		uopt->flags |= (1 << UDF_FLAG_NOVRS);
 534		break;
 535	case Opt_bs:
 536		n = result.uint_32;
 537		if (n != 512 && n != 1024 && n != 2048 && n != 4096)
 538			return -EINVAL;
 539		uopt->blocksize = n;
 540		uopt->flags |= (1 << UDF_FLAG_BLOCKSIZE_SET);
 541		break;
 542	case Opt_unhide:
 543		uopt->flags |= (1 << UDF_FLAG_UNHIDE);
 544		break;
 545	case Opt_undelete:
 546		uopt->flags |= (1 << UDF_FLAG_UNDELETE);
 547		break;
 548	case Opt_adinicb:
 549		if (result.negated)
 550			uopt->flags &= ~(1 << UDF_FLAG_USE_AD_IN_ICB);
 551		else
 552			uopt->flags |= (1 << UDF_FLAG_USE_AD_IN_ICB);
 553		break;
 554	case Opt_shortad:
 555		uopt->flags |= (1 << UDF_FLAG_USE_SHORT_AD);
 556		break;
 557	case Opt_longad:
 558		uopt->flags &= ~(1 << UDF_FLAG_USE_SHORT_AD);
 559		break;
 560	case Opt_gid:
 561		if (kstrtoint(param->string, 10, &uv) == 0) {
 562			kgid_t gid = make_kgid(current_user_ns(), uv);
 563			if (!gid_valid(gid))
 564				return -EINVAL;
 565			uopt->gid = gid;
 566			uopt->flags |= (1 << UDF_FLAG_GID_SET);
 567		} else if (!strcmp(param->string, "forget")) {
 568			uopt->flags |= (1 << UDF_FLAG_GID_FORGET);
 569		} else if (!strcmp(param->string, "ignore")) {
 570			/* this option is superseded by gid=<number> */
 571			;
 572		} else {
 573			return -EINVAL;
 574		}
 575		break;
 576	case Opt_uid:
 577		if (kstrtoint(param->string, 10, &uv) == 0) {
 578			kuid_t uid = make_kuid(current_user_ns(), uv);
 579			if (!uid_valid(uid))
 580				return -EINVAL;
 581			uopt->uid = uid;
 582			uopt->flags |= (1 << UDF_FLAG_UID_SET);
 583		} else if (!strcmp(param->string, "forget")) {
 584			uopt->flags |= (1 << UDF_FLAG_UID_FORGET);
 585		} else if (!strcmp(param->string, "ignore")) {
 586			/* this option is superseded by uid=<number> */
 587			;
 588		} else {
 589			return -EINVAL;
 590		}
 591		break;
 592	case Opt_umask:
 593		uopt->umask = result.uint_32;
 594		break;
 595	case Opt_nostrict:
 596		uopt->flags &= ~(1 << UDF_FLAG_STRICT);
 597		break;
 598	case Opt_session:
 599		uopt->session = result.uint_32;
 600		if (!remount)
 601			uopt->flags |= (1 << UDF_FLAG_SESSION_SET);
 602		break;
 603	case Opt_lastblock:
 604		uopt->lastblock = result.uint_32;
 605		if (!remount)
 606			uopt->flags |= (1 << UDF_FLAG_LASTBLOCK_SET);
 607		break;
 608	case Opt_anchor:
 609		uopt->anchor = result.uint_32;
 610		break;
 611	case Opt_volume:
 612	case Opt_partition:
 613	case Opt_fileset:
 614	case Opt_rootdir:
 615		/* Ignored (never implemented properly) */
 616		break;
 617	case Opt_utf8:
 618		if (!remount) {
 619			unload_nls(uopt->nls_map);
 620			uopt->nls_map = NULL;
 621		}
 622		break;
 623	case Opt_iocharset:
 624		if (!remount) {
 625			unload_nls(uopt->nls_map);
 626			uopt->nls_map = NULL;
 627		}
 628		/* When nls_map is not loaded then UTF-8 is used */
 629		if (!remount && strcmp(param->string, "utf8") != 0) {
 630			uopt->nls_map = load_nls(param->string);
 631			if (!uopt->nls_map) {
 632				errorf(fc, "iocharset %s not found",
 633					param->string);
 634				return -EINVAL;
 635			}
 636		}
 637		break;
 638	case Opt_fmode:
 639		uopt->fmode = result.uint_32 & 0777;
 640		break;
 641	case Opt_dmode:
 642		uopt->dmode = result.uint_32 & 0777;
 643		break;
 644	default:
 645		return -EINVAL;
 646	}
 647	return 0;
 648}
 649
 650static int udf_reconfigure(struct fs_context *fc)
 651{
 652	struct udf_options *uopt = fc->fs_private;
 653	struct super_block *sb = fc->root->d_sb;
 654	struct udf_sb_info *sbi = UDF_SB(sb);
 655	int readonly = fc->sb_flags & SB_RDONLY;
 656	int error = 0;
 657
 658	if (!readonly && UDF_QUERY_FLAG(sb, UDF_FLAG_RW_INCOMPAT))
 659		return -EACCES;
 660
 661	sync_filesystem(sb);
 662
 663	write_lock(&sbi->s_cred_lock);
 664	sbi->s_flags = uopt->flags;
 665	sbi->s_uid   = uopt->uid;
 666	sbi->s_gid   = uopt->gid;
 667	sbi->s_umask = uopt->umask;
 668	sbi->s_fmode = uopt->fmode;
 669	sbi->s_dmode = uopt->dmode;
 670	write_unlock(&sbi->s_cred_lock);
 671
 672	if (readonly == sb_rdonly(sb))
 673		goto out_unlock;
 674
 675	if (readonly)
 676		udf_close_lvid(sb);
 677	else
 678		udf_open_lvid(sb);
 679
 680out_unlock:
 681	return error;
 682}
 683
 684/*
 685 * Check VSD descriptor. Returns -1 in case we are at the end of volume
 686 * recognition area, 0 if the descriptor is valid but non-interesting, 1 if
 687 * we found one of NSR descriptors we are looking for.
 688 */
 689static int identify_vsd(const struct volStructDesc *vsd)
 690{
 691	int ret = 0;
 692
 693	if (!memcmp(vsd->stdIdent, VSD_STD_ID_CD001, VSD_STD_ID_LEN)) {
 694		switch (vsd->structType) {
 695		case 0:
 696			udf_debug("ISO9660 Boot Record found\n");
 697			break;
 698		case 1:
 699			udf_debug("ISO9660 Primary Volume Descriptor found\n");
 700			break;
 701		case 2:
 702			udf_debug("ISO9660 Supplementary Volume Descriptor found\n");
 703			break;
 704		case 3:
 705			udf_debug("ISO9660 Volume Partition Descriptor found\n");
 706			break;
 707		case 255:
 708			udf_debug("ISO9660 Volume Descriptor Set Terminator found\n");
 709			break;
 710		default:
 711			udf_debug("ISO9660 VRS (%u) found\n", vsd->structType);
 712			break;
 713		}
 714	} else if (!memcmp(vsd->stdIdent, VSD_STD_ID_BEA01, VSD_STD_ID_LEN))
 715		; /* ret = 0 */
 716	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_NSR02, VSD_STD_ID_LEN))
 717		ret = 1;
 718	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_NSR03, VSD_STD_ID_LEN))
 719		ret = 1;
 720	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_BOOT2, VSD_STD_ID_LEN))
 721		; /* ret = 0 */
 722	else if (!memcmp(vsd->stdIdent, VSD_STD_ID_CDW02, VSD_STD_ID_LEN))
 723		; /* ret = 0 */
 724	else {
 725		/* TEA01 or invalid id : end of volume recognition area */
 726		ret = -1;
 727	}
 728
 729	return ret;
 730}
 731
 732/*
 733 * Check Volume Structure Descriptors (ECMA 167 2/9.1)
 734 * We also check any "CD-ROM Volume Descriptor Set" (ECMA 167 2/8.3.1)
 735 * @return   1 if NSR02 or NSR03 found,
 736 *	    -1 if first sector read error, 0 otherwise
 737 */
 738static int udf_check_vsd(struct super_block *sb)
 739{
 740	struct volStructDesc *vsd = NULL;
 741	loff_t sector = VSD_FIRST_SECTOR_OFFSET;
 742	int sectorsize;
 743	struct buffer_head *bh = NULL;
 744	int nsr = 0;
 745	struct udf_sb_info *sbi;
 746	loff_t session_offset;
 747
 748	sbi = UDF_SB(sb);
 749	if (sb->s_blocksize < sizeof(struct volStructDesc))
 750		sectorsize = sizeof(struct volStructDesc);
 751	else
 752		sectorsize = sb->s_blocksize;
 753
 754	session_offset = (loff_t)sbi->s_session << sb->s_blocksize_bits;
 755	sector += session_offset;
 756
 757	udf_debug("Starting at sector %u (%lu byte sectors)\n",
 758		  (unsigned int)(sector >> sb->s_blocksize_bits),
 759		  sb->s_blocksize);
 760	/* Process the sequence (if applicable). The hard limit on the sector
 761	 * offset is arbitrary, hopefully large enough so that all valid UDF
 762	 * filesystems will be recognised. There is no mention of an upper
 763	 * bound to the size of the volume recognition area in the standard.
 764	 *  The limit will prevent the code to read all the sectors of a
 765	 * specially crafted image (like a bluray disc full of CD001 sectors),
 766	 * potentially causing minutes or even hours of uninterruptible I/O
 767	 * activity. This actually happened with uninitialised SSD partitions
 768	 * (all 0xFF) before the check for the limit and all valid IDs were
 769	 * added */
 770	for (; !nsr && sector < VSD_MAX_SECTOR_OFFSET; sector += sectorsize) {
 771		/* Read a block */
 772		bh = sb_bread(sb, sector >> sb->s_blocksize_bits);
 773		if (!bh)
 774			break;
 775
 776		vsd = (struct volStructDesc *)(bh->b_data +
 777					      (sector & (sb->s_blocksize - 1)));
 778		nsr = identify_vsd(vsd);
 779		/* Found NSR or end? */
 780		if (nsr) {
 781			brelse(bh);
 782			break;
 783		}
 784		/*
 785		 * Special handling for improperly formatted VRS (e.g., Win10)
 786		 * where components are separated by 2048 bytes even though
 787		 * sectors are 4K
 788		 */
 789		if (sb->s_blocksize == 4096) {
 790			nsr = identify_vsd(vsd + 1);
 791			/* Ignore unknown IDs... */
 792			if (nsr < 0)
 793				nsr = 0;
 794		}
 795		brelse(bh);
 796	}
 797
 798	if (nsr > 0)
 799		return 1;
 800	else if (!bh && sector - session_offset == VSD_FIRST_SECTOR_OFFSET)
 801		return -1;
 802	else
 803		return 0;
 804}
 805
 806static int udf_verify_domain_identifier(struct super_block *sb,
 807					struct regid *ident, char *dname)
 808{
 809	struct domainIdentSuffix *suffix;
 810
 811	if (memcmp(ident->ident, UDF_ID_COMPLIANT, strlen(UDF_ID_COMPLIANT))) {
 812		udf_warn(sb, "Not OSTA UDF compliant %s descriptor.\n", dname);
 813		goto force_ro;
 814	}
 815	if (ident->flags & ENTITYID_FLAGS_DIRTY) {
 816		udf_warn(sb, "Possibly not OSTA UDF compliant %s descriptor.\n",
 817			 dname);
 818		goto force_ro;
 819	}
 820	suffix = (struct domainIdentSuffix *)ident->identSuffix;
 821	if ((suffix->domainFlags & DOMAIN_FLAGS_HARD_WRITE_PROTECT) ||
 822	    (suffix->domainFlags & DOMAIN_FLAGS_SOFT_WRITE_PROTECT)) {
 823		if (!sb_rdonly(sb)) {
 824			udf_warn(sb, "Descriptor for %s marked write protected."
 825				 " Forcing read only mount.\n", dname);
 826		}
 827		goto force_ro;
 828	}
 829	return 0;
 830
 831force_ro:
 832	if (!sb_rdonly(sb))
 833		return -EACCES;
 834	UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
 835	return 0;
 836}
 837
 838static int udf_load_fileset(struct super_block *sb, struct fileSetDesc *fset,
 839			    struct kernel_lb_addr *root)
 840{
 841	int ret;
 842
 843	ret = udf_verify_domain_identifier(sb, &fset->domainIdent, "file set");
 844	if (ret < 0)
 845		return ret;
 846
 847	*root = lelb_to_cpu(fset->rootDirectoryICB.extLocation);
 848	UDF_SB(sb)->s_serial_number = le16_to_cpu(fset->descTag.tagSerialNum);
 849
 850	udf_debug("Rootdir at block=%u, partition=%u\n",
 851		  root->logicalBlockNum, root->partitionReferenceNum);
 852	return 0;
 853}
 854
 855static int udf_find_fileset(struct super_block *sb,
 856			    struct kernel_lb_addr *fileset,
 857			    struct kernel_lb_addr *root)
 858{
 859	struct buffer_head *bh;
 860	uint16_t ident;
 861	int ret;
 862
 863	if (fileset->logicalBlockNum == 0xFFFFFFFF &&
 864	    fileset->partitionReferenceNum == 0xFFFF)
 865		return -EINVAL;
 866
 867	bh = udf_read_ptagged(sb, fileset, 0, &ident);
 868	if (!bh)
 869		return -EIO;
 870	if (ident != TAG_IDENT_FSD) {
 871		brelse(bh);
 872		return -EINVAL;
 873	}
 874
 875	udf_debug("Fileset at block=%u, partition=%u\n",
 876		  fileset->logicalBlockNum, fileset->partitionReferenceNum);
 877
 878	UDF_SB(sb)->s_partition = fileset->partitionReferenceNum;
 879	ret = udf_load_fileset(sb, (struct fileSetDesc *)bh->b_data, root);
 880	brelse(bh);
 881	return ret;
 882}
 883
 884/*
 885 * Load primary Volume Descriptor Sequence
 886 *
 887 * Return <0 on error, 0 on success. -EAGAIN is special meaning next sequence
 888 * should be tried.
 889 */
 890static int udf_load_pvoldesc(struct super_block *sb, sector_t block)
 891{
 892	struct primaryVolDesc *pvoldesc;
 893	uint8_t *outstr;
 894	struct buffer_head *bh;
 895	uint16_t ident;
 896	int ret;
 897	struct timestamp *ts;
 898
 899	outstr = kzalloc(128, GFP_KERNEL);
 900	if (!outstr)
 901		return -ENOMEM;
 902
 903	bh = udf_read_tagged(sb, block, block, &ident);
 904	if (!bh) {
 905		ret = -EAGAIN;
 906		goto out2;
 907	}
 908
 909	if (ident != TAG_IDENT_PVD) {
 910		ret = -EIO;
 911		goto out_bh;
 912	}
 913
 914	pvoldesc = (struct primaryVolDesc *)bh->b_data;
 915
 916	udf_disk_stamp_to_time(&UDF_SB(sb)->s_record_time,
 917			      pvoldesc->recordingDateAndTime);
 918	ts = &pvoldesc->recordingDateAndTime;
 919	udf_debug("recording time %04u/%02u/%02u %02u:%02u (%x)\n",
 920		  le16_to_cpu(ts->year), ts->month, ts->day, ts->hour,
 921		  ts->minute, le16_to_cpu(ts->typeAndTimezone));
 922
 923	ret = udf_dstrCS0toChar(sb, outstr, 31, pvoldesc->volIdent, 32);
 924	if (ret < 0) {
 925		strscpy_pad(UDF_SB(sb)->s_volume_ident, "InvalidName");
 926		pr_warn("incorrect volume identification, setting to "
 927			"'InvalidName'\n");
 928	} else {
 929		strscpy_pad(UDF_SB(sb)->s_volume_ident, outstr);
 930	}
 931	udf_debug("volIdent[] = '%s'\n", UDF_SB(sb)->s_volume_ident);
 932
 933	ret = udf_dstrCS0toChar(sb, outstr, 127, pvoldesc->volSetIdent, 128);
 934	if (ret < 0) {
 935		ret = 0;
 936		goto out_bh;
 937	}
 938	outstr[ret] = 0;
 939	udf_debug("volSetIdent[] = '%s'\n", outstr);
 940
 941	ret = 0;
 942out_bh:
 943	brelse(bh);
 944out2:
 945	kfree(outstr);
 946	return ret;
 947}
 948
 949struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
 950					u32 meta_file_loc, u32 partition_ref)
 951{
 952	struct kernel_lb_addr addr;
 953	struct inode *metadata_fe;
 954
 955	addr.logicalBlockNum = meta_file_loc;
 956	addr.partitionReferenceNum = partition_ref;
 957
 958	metadata_fe = udf_iget_special(sb, &addr);
 959
 960	if (IS_ERR(metadata_fe)) {
 961		udf_warn(sb, "metadata inode efe not found\n");
 962		return metadata_fe;
 963	}
 964	if (UDF_I(metadata_fe)->i_alloc_type != ICBTAG_FLAG_AD_SHORT) {
 965		udf_warn(sb, "metadata inode efe does not have short allocation descriptors!\n");
 966		iput(metadata_fe);
 967		return ERR_PTR(-EIO);
 968	}
 969
 970	return metadata_fe;
 971}
 972
 973static int udf_load_metadata_files(struct super_block *sb, int partition,
 974				   int type1_index)
 975{
 976	struct udf_sb_info *sbi = UDF_SB(sb);
 977	struct udf_part_map *map;
 978	struct udf_meta_data *mdata;
 979	struct kernel_lb_addr addr;
 980	struct inode *fe;
 981
 982	map = &sbi->s_partmaps[partition];
 983	mdata = &map->s_type_specific.s_metadata;
 984	mdata->s_phys_partition_ref = type1_index;
 985
 986	/* metadata address */
 987	udf_debug("Metadata file location: block = %u part = %u\n",
 988		  mdata->s_meta_file_loc, mdata->s_phys_partition_ref);
 989
 990	fe = udf_find_metadata_inode_efe(sb, mdata->s_meta_file_loc,
 991					 mdata->s_phys_partition_ref);
 992	if (IS_ERR(fe)) {
 993		/* mirror file entry */
 994		udf_debug("Mirror metadata file location: block = %u part = %u\n",
 995			  mdata->s_mirror_file_loc, mdata->s_phys_partition_ref);
 996
 997		fe = udf_find_metadata_inode_efe(sb, mdata->s_mirror_file_loc,
 998						 mdata->s_phys_partition_ref);
 999
1000		if (IS_ERR(fe)) {
1001			udf_err(sb, "Both metadata and mirror metadata inode efe can not found\n");
1002			return PTR_ERR(fe);
1003		}
1004		mdata->s_mirror_fe = fe;
1005	} else
1006		mdata->s_metadata_fe = fe;
1007
1008
1009	/*
1010	 * bitmap file entry
1011	 * Note:
1012	 * Load only if bitmap file location differs from 0xFFFFFFFF (DCN-5102)
1013	*/
1014	if (mdata->s_bitmap_file_loc != 0xFFFFFFFF) {
1015		addr.logicalBlockNum = mdata->s_bitmap_file_loc;
1016		addr.partitionReferenceNum = mdata->s_phys_partition_ref;
1017
1018		udf_debug("Bitmap file location: block = %u part = %u\n",
1019			  addr.logicalBlockNum, addr.partitionReferenceNum);
1020
1021		fe = udf_iget_special(sb, &addr);
1022		if (IS_ERR(fe)) {
1023			if (sb_rdonly(sb))
1024				udf_warn(sb, "bitmap inode efe not found but it's ok since the disc is mounted read-only\n");
1025			else {
1026				udf_err(sb, "bitmap inode efe not found and attempted read-write mount\n");
1027				return PTR_ERR(fe);
1028			}
1029		} else
1030			mdata->s_bitmap_fe = fe;
1031	}
1032
1033	udf_debug("udf_load_metadata_files Ok\n");
1034	return 0;
1035}
1036
1037int udf_compute_nr_groups(struct super_block *sb, u32 partition)
1038{
1039	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
1040	return DIV_ROUND_UP(map->s_partition_len +
1041			    (sizeof(struct spaceBitmapDesc) << 3),
1042			    sb->s_blocksize * 8);
1043}
1044
1045static struct udf_bitmap *udf_sb_alloc_bitmap(struct super_block *sb, u32 index)
1046{
1047	struct udf_bitmap *bitmap;
1048	int nr_groups = udf_compute_nr_groups(sb, index);
1049
1050	bitmap = kvzalloc(struct_size(bitmap, s_block_bitmap, nr_groups),
1051			  GFP_KERNEL);
1052	if (!bitmap)
1053		return NULL;
1054
1055	bitmap->s_nr_groups = nr_groups;
1056	return bitmap;
1057}
1058
1059static int check_partition_desc(struct super_block *sb,
1060				struct partitionDesc *p,
1061				struct udf_part_map *map)
1062{
1063	bool umap, utable, fmap, ftable;
1064	struct partitionHeaderDesc *phd;
1065
1066	switch (le32_to_cpu(p->accessType)) {
1067	case PD_ACCESS_TYPE_READ_ONLY:
1068	case PD_ACCESS_TYPE_WRITE_ONCE:
1069	case PD_ACCESS_TYPE_NONE:
1070		goto force_ro;
1071	}
1072
1073	/* No Partition Header Descriptor? */
1074	if (strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR02) &&
1075	    strcmp(p->partitionContents.ident, PD_PARTITION_CONTENTS_NSR03))
1076		goto force_ro;
1077
1078	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1079	utable = phd->unallocSpaceTable.extLength;
1080	umap = phd->unallocSpaceBitmap.extLength;
1081	ftable = phd->freedSpaceTable.extLength;
1082	fmap = phd->freedSpaceBitmap.extLength;
1083
1084	/* No allocation info? */
1085	if (!utable && !umap && !ftable && !fmap)
1086		goto force_ro;
1087
1088	/* We don't support blocks that require erasing before overwrite */
1089	if (ftable || fmap)
1090		goto force_ro;
1091	/* UDF 2.60: 2.3.3 - no mixing of tables & bitmaps, no VAT. */
1092	if (utable && umap)
1093		goto force_ro;
1094
1095	if (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1096	    map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1097	    map->s_partition_type == UDF_METADATA_MAP25)
1098		goto force_ro;
1099
1100	return 0;
1101force_ro:
1102	if (!sb_rdonly(sb))
1103		return -EACCES;
1104	UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1105	return 0;
1106}
1107
1108static int udf_fill_partdesc_info(struct super_block *sb,
1109		struct partitionDesc *p, int p_index)
1110{
1111	struct udf_part_map *map;
1112	struct udf_sb_info *sbi = UDF_SB(sb);
1113	struct partitionHeaderDesc *phd;
1114	u32 sum;
1115	int err;
1116
1117	map = &sbi->s_partmaps[p_index];
1118
1119	map->s_partition_len = le32_to_cpu(p->partitionLength); /* blocks */
1120	map->s_partition_root = le32_to_cpu(p->partitionStartingLocation);
1121	if (check_add_overflow(map->s_partition_root, map->s_partition_len,
1122			       &sum)) {
1123		udf_err(sb, "Partition %d has invalid location %u + %u\n",
1124			p_index, map->s_partition_root, map->s_partition_len);
1125		return -EFSCORRUPTED;
1126	}
1127
1128	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_READ_ONLY))
1129		map->s_partition_flags |= UDF_PART_FLAG_READ_ONLY;
1130	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_WRITE_ONCE))
1131		map->s_partition_flags |= UDF_PART_FLAG_WRITE_ONCE;
1132	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_REWRITABLE))
1133		map->s_partition_flags |= UDF_PART_FLAG_REWRITABLE;
1134	if (p->accessType == cpu_to_le32(PD_ACCESS_TYPE_OVERWRITABLE))
1135		map->s_partition_flags |= UDF_PART_FLAG_OVERWRITABLE;
1136
1137	udf_debug("Partition (%d type %x) starts at physical %u, block length %u\n",
1138		  p_index, map->s_partition_type,
1139		  map->s_partition_root, map->s_partition_len);
1140
1141	err = check_partition_desc(sb, p, map);
1142	if (err)
1143		return err;
1144
1145	/*
1146	 * Skip loading allocation info it we cannot ever write to the fs.
1147	 * This is a correctness thing as we may have decided to force ro mount
1148	 * to avoid allocation info we don't support.
1149	 */
1150	if (UDF_QUERY_FLAG(sb, UDF_FLAG_RW_INCOMPAT))
1151		return 0;
1152
1153	phd = (struct partitionHeaderDesc *)p->partitionContentsUse;
1154	if (phd->unallocSpaceTable.extLength) {
1155		struct kernel_lb_addr loc = {
1156			.logicalBlockNum = le32_to_cpu(
1157				phd->unallocSpaceTable.extPosition),
1158			.partitionReferenceNum = p_index,
1159		};
1160		struct inode *inode;
1161
1162		inode = udf_iget_special(sb, &loc);
1163		if (IS_ERR(inode)) {
1164			udf_debug("cannot load unallocSpaceTable (part %d)\n",
1165				  p_index);
1166			return PTR_ERR(inode);
1167		}
1168		map->s_uspace.s_table = inode;
1169		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_TABLE;
1170		udf_debug("unallocSpaceTable (part %d) @ %lu\n",
1171			  p_index, map->s_uspace.s_table->i_ino);
1172	}
1173
1174	if (phd->unallocSpaceBitmap.extLength) {
1175		struct udf_bitmap *bitmap = udf_sb_alloc_bitmap(sb, p_index);
1176		if (!bitmap)
1177			return -ENOMEM;
1178		map->s_uspace.s_bitmap = bitmap;
1179		bitmap->s_extPosition = le32_to_cpu(
1180				phd->unallocSpaceBitmap.extPosition);
1181		map->s_partition_flags |= UDF_PART_FLAG_UNALLOC_BITMAP;
1182		/* Check whether math over bitmap won't overflow. */
1183		if (check_add_overflow(map->s_partition_len,
1184				       sizeof(struct spaceBitmapDesc) << 3,
1185				       &sum)) {
1186			udf_err(sb, "Partition %d is too long (%u)\n", p_index,
1187				map->s_partition_len);
1188			return -EFSCORRUPTED;
1189		}
1190		udf_debug("unallocSpaceBitmap (part %d) @ %u\n",
1191			  p_index, bitmap->s_extPosition);
1192	}
1193
1194	return 0;
1195}
1196
1197static void udf_find_vat_block(struct super_block *sb, int p_index,
1198			       int type1_index, sector_t start_block)
1199{
1200	struct udf_sb_info *sbi = UDF_SB(sb);
1201	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1202	sector_t vat_block;
1203	struct kernel_lb_addr ino;
1204	struct inode *inode;
1205
1206	/*
1207	 * VAT file entry is in the last recorded block. Some broken disks have
1208	 * it a few blocks before so try a bit harder...
1209	 */
1210	ino.partitionReferenceNum = type1_index;
1211	for (vat_block = start_block;
1212	     vat_block >= map->s_partition_root &&
1213	     vat_block >= start_block - 3; vat_block--) {
1214		ino.logicalBlockNum = vat_block - map->s_partition_root;
1215		inode = udf_iget_special(sb, &ino);
1216		if (!IS_ERR(inode)) {
1217			sbi->s_vat_inode = inode;
1218			break;
1219		}
1220	}
1221}
1222
1223static int udf_load_vat(struct super_block *sb, int p_index, int type1_index)
1224{
1225	struct udf_sb_info *sbi = UDF_SB(sb);
1226	struct udf_part_map *map = &sbi->s_partmaps[p_index];
1227	struct buffer_head *bh = NULL;
1228	struct udf_inode_info *vati;
1229	struct virtualAllocationTable20 *vat20;
1230	sector_t blocks = sb_bdev_nr_blocks(sb);
1231
1232	udf_find_vat_block(sb, p_index, type1_index, sbi->s_last_block);
1233	if (!sbi->s_vat_inode &&
1234	    sbi->s_last_block != blocks - 1) {
1235		pr_notice("Failed to read VAT inode from the last recorded block (%lu), retrying with the last block of the device (%lu).\n",
1236			  (unsigned long)sbi->s_last_block,
1237			  (unsigned long)blocks - 1);
1238		udf_find_vat_block(sb, p_index, type1_index, blocks - 1);
1239	}
1240	if (!sbi->s_vat_inode)
1241		return -EIO;
1242
1243	if (map->s_partition_type == UDF_VIRTUAL_MAP15) {
1244		map->s_type_specific.s_virtual.s_start_offset = 0;
1245		map->s_type_specific.s_virtual.s_num_entries =
1246			(sbi->s_vat_inode->i_size - 36) >> 2;
1247	} else if (map->s_partition_type == UDF_VIRTUAL_MAP20) {
1248		vati = UDF_I(sbi->s_vat_inode);
1249		if (vati->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
1250			int err = 0;
1251
1252			bh = udf_bread(sbi->s_vat_inode, 0, 0, &err);
1253			if (!bh) {
1254				if (!err)
1255					err = -EFSCORRUPTED;
1256				return err;
1257			}
1258			vat20 = (struct virtualAllocationTable20 *)bh->b_data;
1259		} else {
1260			vat20 = (struct virtualAllocationTable20 *)
1261							vati->i_data;
1262		}
1263
1264		map->s_type_specific.s_virtual.s_start_offset =
1265			le16_to_cpu(vat20->lengthHeader);
1266		map->s_type_specific.s_virtual.s_num_entries =
1267			(sbi->s_vat_inode->i_size -
1268				map->s_type_specific.s_virtual.
1269					s_start_offset) >> 2;
1270		brelse(bh);
1271	}
1272	return 0;
1273}
1274
1275/*
1276 * Load partition descriptor block
1277 *
1278 * Returns <0 on error, 0 on success, -EAGAIN is special - try next descriptor
1279 * sequence.
1280 */
1281static int udf_load_partdesc(struct super_block *sb, sector_t block)
1282{
1283	struct buffer_head *bh;
1284	struct partitionDesc *p;
1285	struct udf_part_map *map;
1286	struct udf_sb_info *sbi = UDF_SB(sb);
1287	int i, type1_idx;
1288	uint16_t partitionNumber;
1289	uint16_t ident;
1290	int ret;
1291
1292	bh = udf_read_tagged(sb, block, block, &ident);
1293	if (!bh)
1294		return -EAGAIN;
1295	if (ident != TAG_IDENT_PD) {
1296		ret = 0;
1297		goto out_bh;
1298	}
1299
1300	p = (struct partitionDesc *)bh->b_data;
1301	partitionNumber = le16_to_cpu(p->partitionNumber);
1302
1303	/* First scan for TYPE1 and SPARABLE partitions */
1304	for (i = 0; i < sbi->s_partitions; i++) {
1305		map = &sbi->s_partmaps[i];
1306		udf_debug("Searching map: (%u == %u)\n",
1307			  map->s_partition_num, partitionNumber);
1308		if (map->s_partition_num == partitionNumber &&
1309		    (map->s_partition_type == UDF_TYPE1_MAP15 ||
1310		     map->s_partition_type == UDF_SPARABLE_MAP15))
1311			break;
1312	}
1313
1314	if (i >= sbi->s_partitions) {
1315		udf_debug("Partition (%u) not found in partition map\n",
1316			  partitionNumber);
1317		ret = 0;
1318		goto out_bh;
1319	}
1320
1321	ret = udf_fill_partdesc_info(sb, p, i);
1322	if (ret < 0)
1323		goto out_bh;
1324
1325	/*
1326	 * Now rescan for VIRTUAL or METADATA partitions when SPARABLE and
1327	 * PHYSICAL partitions are already set up
1328	 */
1329	type1_idx = i;
1330	map = NULL; /* supress 'maybe used uninitialized' warning */
1331	for (i = 0; i < sbi->s_partitions; i++) {
1332		map = &sbi->s_partmaps[i];
1333
1334		if (map->s_partition_num == partitionNumber &&
1335		    (map->s_partition_type == UDF_VIRTUAL_MAP15 ||
1336		     map->s_partition_type == UDF_VIRTUAL_MAP20 ||
1337		     map->s_partition_type == UDF_METADATA_MAP25))
1338			break;
1339	}
1340
1341	if (i >= sbi->s_partitions) {
1342		ret = 0;
1343		goto out_bh;
1344	}
1345
1346	ret = udf_fill_partdesc_info(sb, p, i);
1347	if (ret < 0)
1348		goto out_bh;
1349
1350	if (map->s_partition_type == UDF_METADATA_MAP25) {
1351		ret = udf_load_metadata_files(sb, i, type1_idx);
1352		if (ret < 0) {
1353			udf_err(sb, "error loading MetaData partition map %d\n",
1354				i);
1355			goto out_bh;
1356		}
1357	} else {
1358		/*
1359		 * If we have a partition with virtual map, we don't handle
1360		 * writing to it (we overwrite blocks instead of relocating
1361		 * them).
1362		 */
1363		if (!sb_rdonly(sb)) {
1364			ret = -EACCES;
1365			goto out_bh;
1366		}
1367		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1368		ret = udf_load_vat(sb, i, type1_idx);
1369		if (ret < 0)
1370			goto out_bh;
1371	}
1372	ret = 0;
1373out_bh:
1374	/* In case loading failed, we handle cleanup in udf_fill_super */
1375	brelse(bh);
1376	return ret;
1377}
1378
1379static int udf_load_sparable_map(struct super_block *sb,
1380				 struct udf_part_map *map,
1381				 struct sparablePartitionMap *spm)
1382{
1383	uint32_t loc;
1384	uint16_t ident;
1385	struct sparingTable *st;
1386	struct udf_sparing_data *sdata = &map->s_type_specific.s_sparing;
1387	int i;
1388	struct buffer_head *bh;
1389
1390	map->s_partition_type = UDF_SPARABLE_MAP15;
1391	sdata->s_packet_len = le16_to_cpu(spm->packetLength);
1392	if (!is_power_of_2(sdata->s_packet_len)) {
1393		udf_err(sb, "error loading logical volume descriptor: "
1394			"Invalid packet length %u\n",
1395			(unsigned)sdata->s_packet_len);
1396		return -EIO;
1397	}
1398	if (spm->numSparingTables > 4) {
1399		udf_err(sb, "error loading logical volume descriptor: "
1400			"Too many sparing tables (%d)\n",
1401			(int)spm->numSparingTables);
1402		return -EIO;
1403	}
1404	if (le32_to_cpu(spm->sizeSparingTable) > sb->s_blocksize) {
1405		udf_err(sb, "error loading logical volume descriptor: "
1406			"Too big sparing table size (%u)\n",
1407			le32_to_cpu(spm->sizeSparingTable));
1408		return -EIO;
1409	}
1410
1411	for (i = 0; i < spm->numSparingTables; i++) {
1412		loc = le32_to_cpu(spm->locSparingTable[i]);
1413		bh = udf_read_tagged(sb, loc, loc, &ident);
1414		if (!bh)
1415			continue;
1416
1417		st = (struct sparingTable *)bh->b_data;
1418		if (ident != 0 ||
1419		    strncmp(st->sparingIdent.ident, UDF_ID_SPARING,
1420			    strlen(UDF_ID_SPARING)) ||
1421		    sizeof(*st) + le16_to_cpu(st->reallocationTableLen) >
1422							sb->s_blocksize) {
1423			brelse(bh);
1424			continue;
1425		}
1426
1427		sdata->s_spar_map[i] = bh;
1428	}
1429	map->s_partition_func = udf_get_pblock_spar15;
1430	return 0;
1431}
1432
1433static int udf_load_logicalvol(struct super_block *sb, sector_t block,
1434			       struct kernel_lb_addr *fileset)
1435{
1436	struct logicalVolDesc *lvd;
1437	int i, offset;
1438	uint8_t type;
1439	struct udf_sb_info *sbi = UDF_SB(sb);
1440	struct genericPartitionMap *gpm;
1441	uint16_t ident;
1442	struct buffer_head *bh;
1443	unsigned int table_len;
1444	int ret;
1445
1446	bh = udf_read_tagged(sb, block, block, &ident);
1447	if (!bh)
1448		return -EAGAIN;
1449	BUG_ON(ident != TAG_IDENT_LVD);
1450	lvd = (struct logicalVolDesc *)bh->b_data;
1451	table_len = le32_to_cpu(lvd->mapTableLength);
1452	if (table_len > sb->s_blocksize - sizeof(*lvd)) {
1453		udf_err(sb, "error loading logical volume descriptor: "
1454			"Partition table too long (%u > %lu)\n", table_len,
1455			sb->s_blocksize - sizeof(*lvd));
1456		ret = -EIO;
1457		goto out_bh;
1458	}
1459
1460	ret = udf_verify_domain_identifier(sb, &lvd->domainIdent,
1461					   "logical volume");
1462	if (ret)
1463		goto out_bh;
1464	ret = udf_sb_alloc_partition_maps(sb, le32_to_cpu(lvd->numPartitionMaps));
1465	if (ret)
1466		goto out_bh;
1467
1468	for (i = 0, offset = 0;
1469	     i < sbi->s_partitions && offset < table_len;
1470	     i++, offset += gpm->partitionMapLength) {
1471		struct udf_part_map *map = &sbi->s_partmaps[i];
1472		gpm = (struct genericPartitionMap *)
1473				&(lvd->partitionMaps[offset]);
1474		type = gpm->partitionMapType;
1475		if (type == 1) {
1476			struct genericPartitionMap1 *gpm1 =
1477				(struct genericPartitionMap1 *)gpm;
1478			map->s_partition_type = UDF_TYPE1_MAP15;
1479			map->s_volumeseqnum = le16_to_cpu(gpm1->volSeqNum);
1480			map->s_partition_num = le16_to_cpu(gpm1->partitionNum);
1481			map->s_partition_func = NULL;
1482		} else if (type == 2) {
1483			struct udfPartitionMap2 *upm2 =
1484						(struct udfPartitionMap2 *)gpm;
1485			if (!strncmp(upm2->partIdent.ident, UDF_ID_VIRTUAL,
1486						strlen(UDF_ID_VIRTUAL))) {
1487				u16 suf =
1488					le16_to_cpu(((__le16 *)upm2->partIdent.
1489							identSuffix)[0]);
1490				if (suf < 0x0200) {
1491					map->s_partition_type =
1492							UDF_VIRTUAL_MAP15;
1493					map->s_partition_func =
1494							udf_get_pblock_virt15;
1495				} else {
1496					map->s_partition_type =
1497							UDF_VIRTUAL_MAP20;
1498					map->s_partition_func =
1499							udf_get_pblock_virt20;
1500				}
1501			} else if (!strncmp(upm2->partIdent.ident,
1502						UDF_ID_SPARABLE,
1503						strlen(UDF_ID_SPARABLE))) {
1504				ret = udf_load_sparable_map(sb, map,
1505					(struct sparablePartitionMap *)gpm);
1506				if (ret < 0)
1507					goto out_bh;
1508			} else if (!strncmp(upm2->partIdent.ident,
1509						UDF_ID_METADATA,
1510						strlen(UDF_ID_METADATA))) {
1511				struct udf_meta_data *mdata =
1512					&map->s_type_specific.s_metadata;
1513				struct metadataPartitionMap *mdm =
1514						(struct metadataPartitionMap *)
1515						&(lvd->partitionMaps[offset]);
1516				udf_debug("Parsing Logical vol part %d type %u  id=%s\n",
1517					  i, type, UDF_ID_METADATA);
1518
1519				map->s_partition_type = UDF_METADATA_MAP25;
1520				map->s_partition_func = udf_get_pblock_meta25;
1521
1522				mdata->s_meta_file_loc   =
1523					le32_to_cpu(mdm->metadataFileLoc);
1524				mdata->s_mirror_file_loc =
1525					le32_to_cpu(mdm->metadataMirrorFileLoc);
1526				mdata->s_bitmap_file_loc =
1527					le32_to_cpu(mdm->metadataBitmapFileLoc);
1528				mdata->s_alloc_unit_size =
1529					le32_to_cpu(mdm->allocUnitSize);
1530				mdata->s_align_unit_size =
1531					le16_to_cpu(mdm->alignUnitSize);
1532				if (mdm->flags & 0x01)
1533					mdata->s_flags |= MF_DUPLICATE_MD;
1534
1535				udf_debug("Metadata Ident suffix=0x%x\n",
1536					  le16_to_cpu(*(__le16 *)
1537						      mdm->partIdent.identSuffix));
1538				udf_debug("Metadata part num=%u\n",
1539					  le16_to_cpu(mdm->partitionNum));
1540				udf_debug("Metadata part alloc unit size=%u\n",
1541					  le32_to_cpu(mdm->allocUnitSize));
1542				udf_debug("Metadata file loc=%u\n",
1543					  le32_to_cpu(mdm->metadataFileLoc));
1544				udf_debug("Mirror file loc=%u\n",
1545					  le32_to_cpu(mdm->metadataMirrorFileLoc));
1546				udf_debug("Bitmap file loc=%u\n",
1547					  le32_to_cpu(mdm->metadataBitmapFileLoc));
1548				udf_debug("Flags: %d %u\n",
1549					  mdata->s_flags, mdm->flags);
1550			} else {
1551				udf_debug("Unknown ident: %s\n",
1552					  upm2->partIdent.ident);
1553				continue;
1554			}
1555			map->s_volumeseqnum = le16_to_cpu(upm2->volSeqNum);
1556			map->s_partition_num = le16_to_cpu(upm2->partitionNum);
1557		}
1558		udf_debug("Partition (%d:%u) type %u on volume %u\n",
1559			  i, map->s_partition_num, type, map->s_volumeseqnum);
1560	}
1561
1562	if (fileset) {
1563		struct long_ad *la = (struct long_ad *)&(lvd->logicalVolContentsUse[0]);
1564
1565		*fileset = lelb_to_cpu(la->extLocation);
1566		udf_debug("FileSet found in LogicalVolDesc at block=%u, partition=%u\n",
1567			  fileset->logicalBlockNum,
1568			  fileset->partitionReferenceNum);
1569	}
1570	if (lvd->integritySeqExt.extLength)
1571		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
1572	ret = 0;
1573
1574	if (!sbi->s_lvid_bh) {
1575		/* We can't generate unique IDs without a valid LVID */
1576		if (sb_rdonly(sb)) {
1577			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1578		} else {
1579			udf_warn(sb, "Damaged or missing LVID, forcing "
1580				     "readonly mount\n");
1581			ret = -EACCES;
1582		}
1583	}
1584out_bh:
1585	brelse(bh);
1586	return ret;
1587}
1588
1589static bool udf_lvid_valid(struct super_block *sb,
1590			   struct logicalVolIntegrityDesc *lvid)
1591{
1592	u32 parts, impuselen;
1593
1594	parts = le32_to_cpu(lvid->numOfPartitions);
1595	impuselen = le32_to_cpu(lvid->lengthOfImpUse);
1596	if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
1597	    sizeof(struct logicalVolIntegrityDesc) + impuselen +
1598	    2 * parts * sizeof(u32) > sb->s_blocksize)
1599		return false;
1600	return true;
1601}
1602
1603/*
1604 * Find the prevailing Logical Volume Integrity Descriptor.
1605 */
1606static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_ad loc)
1607{
1608	struct buffer_head *bh, *final_bh;
1609	uint16_t ident;
1610	struct udf_sb_info *sbi = UDF_SB(sb);
1611	struct logicalVolIntegrityDesc *lvid;
1612	int indirections = 0;
1613
1614	while (++indirections <= UDF_MAX_LVID_NESTING) {
1615		final_bh = NULL;
1616		while (loc.extLength > 0 &&
1617			(bh = udf_read_tagged(sb, loc.extLocation,
1618					loc.extLocation, &ident))) {
1619			if (ident != TAG_IDENT_LVID) {
1620				brelse(bh);
1621				break;
1622			}
1623
1624			brelse(final_bh);
1625			final_bh = bh;
1626
1627			loc.extLength -= sb->s_blocksize;
1628			loc.extLocation++;
1629		}
1630
1631		if (!final_bh)
1632			return;
1633
1634		lvid = (struct logicalVolIntegrityDesc *)final_bh->b_data;
1635		if (udf_lvid_valid(sb, lvid)) {
1636			brelse(sbi->s_lvid_bh);
1637			sbi->s_lvid_bh = final_bh;
1638		} else {
1639			udf_warn(sb, "Corrupted LVID (parts=%u, impuselen=%u), "
1640				 "ignoring.\n",
1641				 le32_to_cpu(lvid->numOfPartitions),
1642				 le32_to_cpu(lvid->lengthOfImpUse));
1643		}
1644
1645		if (lvid->nextIntegrityExt.extLength == 0)
1646			return;
1647
1648		loc = leea_to_cpu(lvid->nextIntegrityExt);
1649	}
1650
1651	udf_warn(sb, "Too many LVID indirections (max %u), ignoring.\n",
1652		UDF_MAX_LVID_NESTING);
1653	brelse(sbi->s_lvid_bh);
1654	sbi->s_lvid_bh = NULL;
1655}
1656
1657/*
1658 * Step for reallocation of table of partition descriptor sequence numbers.
1659 * Must be power of 2.
1660 */
1661#define PART_DESC_ALLOC_STEP 32
1662
1663struct part_desc_seq_scan_data {
1664	struct udf_vds_record rec;
1665	u32 partnum;
1666};
1667
1668struct desc_seq_scan_data {
1669	struct udf_vds_record vds[VDS_POS_LENGTH];
1670	unsigned int size_part_descs;
1671	unsigned int num_part_descs;
1672	struct part_desc_seq_scan_data *part_descs_loc;
1673};
1674
1675static struct udf_vds_record *handle_partition_descriptor(
1676				struct buffer_head *bh,
1677				struct desc_seq_scan_data *data)
1678{
1679	struct partitionDesc *desc = (struct partitionDesc *)bh->b_data;
1680	int partnum;
1681	int i;
1682
1683	partnum = le16_to_cpu(desc->partitionNumber);
1684	for (i = 0; i < data->num_part_descs; i++)
1685		if (partnum == data->part_descs_loc[i].partnum)
1686			return &(data->part_descs_loc[i].rec);
1687	if (data->num_part_descs >= data->size_part_descs) {
1688		struct part_desc_seq_scan_data *new_loc;
1689		unsigned int new_size = ALIGN(partnum, PART_DESC_ALLOC_STEP);
1690
1691		new_loc = kcalloc(new_size, sizeof(*new_loc), GFP_KERNEL);
1692		if (!new_loc)
1693			return ERR_PTR(-ENOMEM);
1694		memcpy(new_loc, data->part_descs_loc,
1695		       data->size_part_descs * sizeof(*new_loc));
1696		kfree(data->part_descs_loc);
1697		data->part_descs_loc = new_loc;
1698		data->size_part_descs = new_size;
1699	}
1700	return &(data->part_descs_loc[data->num_part_descs++].rec);
1701}
1702
1703
1704static struct udf_vds_record *get_volume_descriptor_record(uint16_t ident,
1705		struct buffer_head *bh, struct desc_seq_scan_data *data)
1706{
1707	switch (ident) {
1708	case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1709		return &(data->vds[VDS_POS_PRIMARY_VOL_DESC]);
1710	case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1711		return &(data->vds[VDS_POS_IMP_USE_VOL_DESC]);
1712	case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1713		return &(data->vds[VDS_POS_LOGICAL_VOL_DESC]);
1714	case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1715		return &(data->vds[VDS_POS_UNALLOC_SPACE_DESC]);
1716	case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1717		return handle_partition_descriptor(bh, data);
1718	}
1719	return NULL;
1720}
1721
1722/*
1723 * Process a main/reserve volume descriptor sequence.
1724 *   @block		First block of first extent of the sequence.
1725 *   @lastblock		Lastblock of first extent of the sequence.
1726 *   @fileset		There we store extent containing root fileset
1727 *
1728 * Returns <0 on error, 0 on success. -EAGAIN is special - try next descriptor
1729 * sequence
1730 */
1731static noinline int udf_process_sequence(
1732		struct super_block *sb,
1733		sector_t block, sector_t lastblock,
1734		struct kernel_lb_addr *fileset)
1735{
1736	struct buffer_head *bh = NULL;
1737	struct udf_vds_record *curr;
1738	struct generic_desc *gd;
1739	struct volDescPtr *vdp;
1740	bool done = false;
1741	uint32_t vdsn;
1742	uint16_t ident;
1743	int ret;
1744	unsigned int indirections = 0;
1745	struct desc_seq_scan_data data;
1746	unsigned int i;
1747
1748	memset(data.vds, 0, sizeof(struct udf_vds_record) * VDS_POS_LENGTH);
1749	data.size_part_descs = PART_DESC_ALLOC_STEP;
1750	data.num_part_descs = 0;
1751	data.part_descs_loc = kcalloc(data.size_part_descs,
1752				      sizeof(*data.part_descs_loc),
1753				      GFP_KERNEL);
1754	if (!data.part_descs_loc)
1755		return -ENOMEM;
1756
1757	/*
1758	 * Read the main descriptor sequence and find which descriptors
1759	 * are in it.
1760	 */
1761	for (; (!done && block <= lastblock); block++) {
1762		bh = udf_read_tagged(sb, block, block, &ident);
1763		if (!bh)
1764			break;
1765
1766		/* Process each descriptor (ISO 13346 3/8.3-8.4) */
1767		gd = (struct generic_desc *)bh->b_data;
1768		vdsn = le32_to_cpu(gd->volDescSeqNum);
1769		switch (ident) {
1770		case TAG_IDENT_VDP: /* ISO 13346 3/10.3 */
1771			if (++indirections > UDF_MAX_TD_NESTING) {
1772				udf_err(sb, "too many Volume Descriptor "
1773					"Pointers (max %u supported)\n",
1774					UDF_MAX_TD_NESTING);
1775				brelse(bh);
1776				ret = -EIO;
1777				goto out;
1778			}
1779
1780			vdp = (struct volDescPtr *)bh->b_data;
1781			block = le32_to_cpu(vdp->nextVolDescSeqExt.extLocation);
1782			lastblock = le32_to_cpu(
1783				vdp->nextVolDescSeqExt.extLength) >>
1784				sb->s_blocksize_bits;
1785			lastblock += block - 1;
1786			/* For loop is going to increment 'block' again */
1787			block--;
1788			break;
1789		case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1790		case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1791		case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1792		case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1793		case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1794			curr = get_volume_descriptor_record(ident, bh, &data);
1795			if (IS_ERR(curr)) {
1796				brelse(bh);
1797				ret = PTR_ERR(curr);
1798				goto out;
1799			}
1800			/* Descriptor we don't care about? */
1801			if (!curr)
1802				break;
1803			if (vdsn >= curr->volDescSeqNum) {
1804				curr->volDescSeqNum = vdsn;
1805				curr->block = block;
1806			}
1807			break;
1808		case TAG_IDENT_TD: /* ISO 13346 3/10.9 */
1809			done = true;
1810			break;
1811		}
1812		brelse(bh);
1813	}
1814	/*
1815	 * Now read interesting descriptors again and process them
1816	 * in a suitable order
1817	 */
1818	if (!data.vds[VDS_POS_PRIMARY_VOL_DESC].block) {
1819		udf_err(sb, "Primary Volume Descriptor not found!\n");
1820		ret = -EAGAIN;
1821		goto out;
1822	}
1823	ret = udf_load_pvoldesc(sb, data.vds[VDS_POS_PRIMARY_VOL_DESC].block);
1824	if (ret < 0)
1825		goto out;
1826
1827	if (data.vds[VDS_POS_LOGICAL_VOL_DESC].block) {
1828		ret = udf_load_logicalvol(sb,
1829				data.vds[VDS_POS_LOGICAL_VOL_DESC].block,
1830				fileset);
1831		if (ret < 0)
1832			goto out;
1833	}
1834
1835	/* Now handle prevailing Partition Descriptors */
1836	for (i = 0; i < data.num_part_descs; i++) {
1837		ret = udf_load_partdesc(sb, data.part_descs_loc[i].rec.block);
1838		if (ret < 0)
1839			goto out;
1840	}
1841	ret = 0;
1842out:
1843	kfree(data.part_descs_loc);
1844	return ret;
1845}
1846
1847/*
1848 * Load Volume Descriptor Sequence described by anchor in bh
1849 *
1850 * Returns <0 on error, 0 on success
1851 */
1852static int udf_load_sequence(struct super_block *sb, struct buffer_head *bh,
1853			     struct kernel_lb_addr *fileset)
1854{
1855	struct anchorVolDescPtr *anchor;
1856	sector_t main_s, main_e, reserve_s, reserve_e;
1857	int ret;
1858
1859	anchor = (struct anchorVolDescPtr *)bh->b_data;
1860
1861	/* Locate the main sequence */
1862	main_s = le32_to_cpu(anchor->mainVolDescSeqExt.extLocation);
1863	main_e = le32_to_cpu(anchor->mainVolDescSeqExt.extLength);
1864	main_e = main_e >> sb->s_blocksize_bits;
1865	main_e += main_s - 1;
1866
1867	/* Locate the reserve sequence */
1868	reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
1869	reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
1870	reserve_e = reserve_e >> sb->s_blocksize_bits;
1871	reserve_e += reserve_s - 1;
1872
1873	/* Process the main & reserve sequences */
1874	/* responsible for finding the PartitionDesc(s) */
1875	ret = udf_process_sequence(sb, main_s, main_e, fileset);
1876	if (ret != -EAGAIN)
1877		return ret;
1878	udf_sb_free_partitions(sb);
1879	ret = udf_process_sequence(sb, reserve_s, reserve_e, fileset);
1880	if (ret < 0) {
1881		udf_sb_free_partitions(sb);
1882		/* No sequence was OK, return -EIO */
1883		if (ret == -EAGAIN)
1884			ret = -EIO;
1885	}
1886	return ret;
1887}
1888
1889/*
1890 * Check whether there is an anchor block in the given block and
1891 * load Volume Descriptor Sequence if so.
1892 *
1893 * Returns <0 on error, 0 on success, -EAGAIN is special - try next anchor
1894 * block
1895 */
1896static int udf_check_anchor_block(struct super_block *sb, sector_t block,
1897				  struct kernel_lb_addr *fileset)
1898{
1899	struct buffer_head *bh;
1900	uint16_t ident;
1901	int ret;
1902
1903	bh = udf_read_tagged(sb, block, block, &ident);
1904	if (!bh)
1905		return -EAGAIN;
1906	if (ident != TAG_IDENT_AVDP) {
1907		brelse(bh);
1908		return -EAGAIN;
1909	}
1910	ret = udf_load_sequence(sb, bh, fileset);
1911	brelse(bh);
1912	return ret;
1913}
1914
1915/*
1916 * Search for an anchor volume descriptor pointer.
1917 *
1918 * Returns < 0 on error, 0 on success. -EAGAIN is special - try next set
1919 * of anchors.
1920 */
1921static int udf_scan_anchors(struct super_block *sb, udf_pblk_t *lastblock,
1922			    struct kernel_lb_addr *fileset)
1923{
1924	udf_pblk_t last[6];
1925	int i;
1926	struct udf_sb_info *sbi = UDF_SB(sb);
1927	int last_count = 0;
1928	int ret;
1929
1930	/* First try user provided anchor */
1931	if (sbi->s_anchor) {
1932		ret = udf_check_anchor_block(sb, sbi->s_anchor, fileset);
1933		if (ret != -EAGAIN)
1934			return ret;
1935	}
1936	/*
1937	 * according to spec, anchor is in either:
1938	 *     block 256
1939	 *     lastblock-256
1940	 *     lastblock
1941	 *  however, if the disc isn't closed, it could be 512.
1942	 */
1943	ret = udf_check_anchor_block(sb, sbi->s_session + 256, fileset);
1944	if (ret != -EAGAIN)
1945		return ret;
1946	/*
1947	 * The trouble is which block is the last one. Drives often misreport
1948	 * this so we try various possibilities.
1949	 */
1950	last[last_count++] = *lastblock;
1951	if (*lastblock >= 1)
1952		last[last_count++] = *lastblock - 1;
1953	last[last_count++] = *lastblock + 1;
1954	if (*lastblock >= 2)
1955		last[last_count++] = *lastblock - 2;
1956	if (*lastblock >= 150)
1957		last[last_count++] = *lastblock - 150;
1958	if (*lastblock >= 152)
1959		last[last_count++] = *lastblock - 152;
1960
1961	for (i = 0; i < last_count; i++) {
1962		if (last[i] >= sb_bdev_nr_blocks(sb))
1963			continue;
1964		ret = udf_check_anchor_block(sb, last[i], fileset);
1965		if (ret != -EAGAIN) {
1966			if (!ret)
1967				*lastblock = last[i];
1968			return ret;
1969		}
1970		if (last[i] < 256)
1971			continue;
1972		ret = udf_check_anchor_block(sb, last[i] - 256, fileset);
1973		if (ret != -EAGAIN) {
1974			if (!ret)
1975				*lastblock = last[i];
1976			return ret;
1977		}
1978	}
1979
1980	/* Finally try block 512 in case media is open */
1981	return udf_check_anchor_block(sb, sbi->s_session + 512, fileset);
1982}
1983
1984/*
1985 * Check Volume Structure Descriptor, find Anchor block and load Volume
1986 * Descriptor Sequence.
1987 *
1988 * Returns < 0 on error, 0 on success. -EAGAIN is special meaning anchor
1989 * block was not found.
1990 */
1991static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
1992			int silent, struct kernel_lb_addr *fileset)
1993{
1994	struct udf_sb_info *sbi = UDF_SB(sb);
1995	int nsr = 0;
1996	int ret;
1997
1998	if (!sb_set_blocksize(sb, uopt->blocksize)) {
1999		if (!silent)
2000			udf_warn(sb, "Bad block size\n");
2001		return -EINVAL;
2002	}
2003	sbi->s_last_block = uopt->lastblock;
2004	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_NOVRS)) {
2005		/* Check that it is NSR02 compliant */
2006		nsr = udf_check_vsd(sb);
2007		if (!nsr) {
2008			if (!silent)
2009				udf_warn(sb, "No VRS found\n");
2010			return -EINVAL;
2011		}
2012		if (nsr == -1)
2013			udf_debug("Failed to read sector at offset %d. "
2014				  "Assuming open disc. Skipping validity "
2015				  "check\n", VSD_FIRST_SECTOR_OFFSET);
2016		if (!sbi->s_last_block)
2017			sbi->s_last_block = udf_get_last_block(sb);
2018	} else {
2019		udf_debug("Validity check skipped because of novrs option\n");
2020	}
2021
2022	/* Look for anchor block and load Volume Descriptor Sequence */
2023	sbi->s_anchor = uopt->anchor;
2024	ret = udf_scan_anchors(sb, &sbi->s_last_block, fileset);
2025	if (ret < 0) {
2026		if (!silent && ret == -EAGAIN)
2027			udf_warn(sb, "No anchor found\n");
2028		return ret;
2029	}
2030	return 0;
2031}
2032
2033static void udf_finalize_lvid(struct logicalVolIntegrityDesc *lvid)
2034{
2035	struct timespec64 ts;
2036
2037	ktime_get_real_ts64(&ts);
2038	udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
2039	lvid->descTag.descCRC = cpu_to_le16(
2040		crc_itu_t(0, (char *)lvid + sizeof(struct tag),
2041			le16_to_cpu(lvid->descTag.descCRCLength)));
2042	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
2043}
2044
2045static void udf_open_lvid(struct super_block *sb)
2046{
2047	struct udf_sb_info *sbi = UDF_SB(sb);
2048	struct buffer_head *bh = sbi->s_lvid_bh;
2049	struct logicalVolIntegrityDesc *lvid;
2050	struct logicalVolIntegrityDescImpUse *lvidiu;
2051
2052	if (!bh)
2053		return;
2054	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2055	lvidiu = udf_sb_lvidiu(sb);
2056	if (!lvidiu)
2057		return;
2058
2059	mutex_lock(&sbi->s_alloc_mutex);
2060	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2061	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2062	if (le32_to_cpu(lvid->integrityType) == LVID_INTEGRITY_TYPE_CLOSE)
2063		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
2064	else
2065		UDF_SET_FLAG(sb, UDF_FLAG_INCONSISTENT);
2066
2067	udf_finalize_lvid(lvid);
2068	mark_buffer_dirty(bh);
2069	sbi->s_lvid_dirty = 0;
2070	mutex_unlock(&sbi->s_alloc_mutex);
2071	/* Make opening of filesystem visible on the media immediately */
2072	sync_dirty_buffer(bh);
2073}
2074
2075static void udf_close_lvid(struct super_block *sb)
2076{
2077	struct udf_sb_info *sbi = UDF_SB(sb);
2078	struct buffer_head *bh = sbi->s_lvid_bh;
2079	struct logicalVolIntegrityDesc *lvid;
2080	struct logicalVolIntegrityDescImpUse *lvidiu;
2081
2082	if (!bh)
2083		return;
2084	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2085	lvidiu = udf_sb_lvidiu(sb);
2086	if (!lvidiu)
2087		return;
2088
2089	mutex_lock(&sbi->s_alloc_mutex);
2090	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2091	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2092	if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
2093		lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
2094	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
2095		lvidiu->minUDFReadRev = cpu_to_le16(sbi->s_udfrev);
2096	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFWriteRev))
2097		lvidiu->minUDFWriteRev = cpu_to_le16(sbi->s_udfrev);
2098	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_INCONSISTENT))
2099		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);
2100
2101	/*
2102	 * We set buffer uptodate unconditionally here to avoid spurious
2103	 * warnings from mark_buffer_dirty() when previous EIO has marked
2104	 * the buffer as !uptodate
2105	 */
2106	set_buffer_uptodate(bh);
2107	udf_finalize_lvid(lvid);
2108	mark_buffer_dirty(bh);
2109	sbi->s_lvid_dirty = 0;
2110	mutex_unlock(&sbi->s_alloc_mutex);
2111	/* Make closing of filesystem visible on the media immediately */
2112	sync_dirty_buffer(bh);
2113}
2114
2115u64 lvid_get_unique_id(struct super_block *sb)
2116{
2117	struct buffer_head *bh;
2118	struct udf_sb_info *sbi = UDF_SB(sb);
2119	struct logicalVolIntegrityDesc *lvid;
2120	struct logicalVolHeaderDesc *lvhd;
2121	u64 uniqueID;
2122	u64 ret;
2123
2124	bh = sbi->s_lvid_bh;
2125	if (!bh)
2126		return 0;
2127
2128	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2129	lvhd = (struct logicalVolHeaderDesc *)lvid->logicalVolContentsUse;
2130
2131	mutex_lock(&sbi->s_alloc_mutex);
2132	ret = uniqueID = le64_to_cpu(lvhd->uniqueID);
2133	if (!(++uniqueID & 0xFFFFFFFF))
2134		uniqueID += 16;
2135	lvhd->uniqueID = cpu_to_le64(uniqueID);
2136	udf_updated_lvid(sb);
2137	mutex_unlock(&sbi->s_alloc_mutex);
2138
2139	return ret;
2140}
2141
2142static int udf_fill_super(struct super_block *sb, struct fs_context *fc)
2143{
2144	int ret = -EINVAL;
2145	struct inode *inode = NULL;
2146	struct udf_options *uopt = fc->fs_private;
2147	struct kernel_lb_addr rootdir, fileset;
2148	struct udf_sb_info *sbi;
2149	bool lvid_open = false;
2150	int silent = fc->sb_flags & SB_SILENT;
2151
2152	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2153	if (!sbi)
2154		return -ENOMEM;
2155
2156	sb->s_fs_info = sbi;
2157
2158	mutex_init(&sbi->s_alloc_mutex);
2159
2160	fileset.logicalBlockNum = 0xFFFFFFFF;
2161	fileset.partitionReferenceNum = 0xFFFF;
2162
2163	sbi->s_flags = uopt->flags;
2164	sbi->s_uid = uopt->uid;
2165	sbi->s_gid = uopt->gid;
2166	sbi->s_umask = uopt->umask;
2167	sbi->s_fmode = uopt->fmode;
2168	sbi->s_dmode = uopt->dmode;
2169	sbi->s_nls_map = uopt->nls_map;
2170	uopt->nls_map = NULL;
2171	rwlock_init(&sbi->s_cred_lock);
2172
2173	if (uopt->session == 0xFFFFFFFF)
2174		sbi->s_session = udf_get_last_session(sb);
2175	else
2176		sbi->s_session = uopt->session;
2177
2178	udf_debug("Multi-session=%d\n", sbi->s_session);
2179
2180	/* Fill in the rest of the superblock */
2181	sb->s_op = &udf_sb_ops;
2182	sb->s_export_op = &udf_export_ops;
2183
2184	sb->s_magic = UDF_SUPER_MAGIC;
2185	sb->s_time_gran = 1000;
2186
2187	if (uopt->flags & (1 << UDF_FLAG_BLOCKSIZE_SET)) {
2188		ret = udf_load_vrs(sb, uopt, silent, &fileset);
2189	} else {
2190		uopt->blocksize = bdev_logical_block_size(sb->s_bdev);
2191		while (uopt->blocksize <= 4096) {
2192			ret = udf_load_vrs(sb, uopt, silent, &fileset);
2193			if (ret < 0) {
2194				if (!silent && ret != -EACCES) {
2195					pr_notice("Scanning with blocksize %u failed\n",
2196						  uopt->blocksize);
2197				}
2198				brelse(sbi->s_lvid_bh);
2199				sbi->s_lvid_bh = NULL;
2200				/*
2201				 * EACCES is special - we want to propagate to
2202				 * upper layers that we cannot handle RW mount.
2203				 */
2204				if (ret == -EACCES)
2205					break;
2206			} else
2207				break;
2208
2209			uopt->blocksize <<= 1;
2210		}
2211	}
2212	if (ret < 0) {
2213		if (ret == -EAGAIN) {
2214			udf_warn(sb, "No partition found (1)\n");
2215			ret = -EINVAL;
2216		}
2217		goto error_out;
2218	}
2219
2220	udf_debug("Lastblock=%u\n", sbi->s_last_block);
2221
2222	if (sbi->s_lvid_bh) {
2223		struct logicalVolIntegrityDescImpUse *lvidiu =
2224							udf_sb_lvidiu(sb);
2225		uint16_t minUDFReadRev;
2226		uint16_t minUDFWriteRev;
2227
2228		if (!lvidiu) {
2229			ret = -EINVAL;
2230			goto error_out;
2231		}
2232		minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev);
2233		minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev);
2234		if (minUDFReadRev > UDF_MAX_READ_VERSION) {
2235			udf_err(sb, "minUDFReadRev=%x (max is %x)\n",
2236				minUDFReadRev,
2237				UDF_MAX_READ_VERSION);
2238			ret = -EINVAL;
2239			goto error_out;
2240		} else if (minUDFWriteRev > UDF_MAX_WRITE_VERSION) {
2241			if (!sb_rdonly(sb)) {
2242				ret = -EACCES;
2243				goto error_out;
2244			}
2245			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2246		}
2247
2248		sbi->s_udfrev = minUDFWriteRev;
2249
2250		if (minUDFReadRev >= UDF_VERS_USE_EXTENDED_FE)
2251			UDF_SET_FLAG(sb, UDF_FLAG_USE_EXTENDED_FE);
2252		if (minUDFReadRev >= UDF_VERS_USE_STREAMS)
2253			UDF_SET_FLAG(sb, UDF_FLAG_USE_STREAMS);
2254	}
2255
2256	if (!sbi->s_partitions) {
2257		udf_warn(sb, "No partition found (2)\n");
2258		ret = -EINVAL;
2259		goto error_out;
2260	}
2261
2262	if (sbi->s_partmaps[sbi->s_partition].s_partition_flags &
2263			UDF_PART_FLAG_READ_ONLY) {
2264		if (!sb_rdonly(sb)) {
2265			ret = -EACCES;
2266			goto error_out;
2267		}
2268		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2269	}
2270
2271	ret = udf_find_fileset(sb, &fileset, &rootdir);
2272	if (ret < 0) {
2273		udf_warn(sb, "No fileset found\n");
2274		goto error_out;
2275	}
2276
2277	if (!silent) {
2278		struct timestamp ts;
2279		udf_time_to_disk_stamp(&ts, sbi->s_record_time);
2280		udf_info("Mounting volume '%s', timestamp %04u/%02u/%02u %02u:%02u (%x)\n",
2281			 sbi->s_volume_ident,
2282			 le16_to_cpu(ts.year), ts.month, ts.day,
2283			 ts.hour, ts.minute, le16_to_cpu(ts.typeAndTimezone));
2284	}
2285	if (!sb_rdonly(sb)) {
2286		udf_open_lvid(sb);
2287		lvid_open = true;
2288	}
2289
2290	/* Assign the root inode */
2291	/* assign inodes by physical block number */
2292	/* perhaps it's not extensible enough, but for now ... */
2293	inode = udf_iget(sb, &rootdir);
2294	if (IS_ERR(inode)) {
2295		udf_err(sb, "Error in udf_iget, block=%u, partition=%u\n",
2296		       rootdir.logicalBlockNum, rootdir.partitionReferenceNum);
2297		ret = PTR_ERR(inode);
2298		goto error_out;
2299	}
2300
2301	/* Allocate a dentry for the root inode */
2302	sb->s_root = d_make_root(inode);
2303	if (!sb->s_root) {
2304		udf_err(sb, "Couldn't allocate root dentry\n");
2305		ret = -ENOMEM;
2306		goto error_out;
2307	}
2308	sb->s_maxbytes = UDF_MAX_FILESIZE;
2309	sb->s_max_links = UDF_MAX_LINKS;
2310	return 0;
2311
2312error_out:
2313	iput(sbi->s_vat_inode);
2314	unload_nls(uopt->nls_map);
2315	if (lvid_open)
2316		udf_close_lvid(sb);
2317	brelse(sbi->s_lvid_bh);
2318	udf_sb_free_partitions(sb);
2319	kfree(sbi);
2320	sb->s_fs_info = NULL;
2321
2322	return ret;
2323}
2324
2325void _udf_err(struct super_block *sb, const char *function,
2326	      const char *fmt, ...)
2327{
2328	struct va_format vaf;
2329	va_list args;
2330
2331	va_start(args, fmt);
2332
2333	vaf.fmt = fmt;
2334	vaf.va = &args;
2335
2336	pr_err("error (device %s): %s: %pV", sb->s_id, function, &vaf);
2337
2338	va_end(args);
2339}
2340
2341void _udf_warn(struct super_block *sb, const char *function,
2342	       const char *fmt, ...)
2343{
2344	struct va_format vaf;
2345	va_list args;
2346
2347	va_start(args, fmt);
2348
2349	vaf.fmt = fmt;
2350	vaf.va = &args;
2351
2352	pr_warn("warning (device %s): %s: %pV", sb->s_id, function, &vaf);
2353
2354	va_end(args);
2355}
2356
2357static void udf_put_super(struct super_block *sb)
2358{
2359	struct udf_sb_info *sbi;
2360
2361	sbi = UDF_SB(sb);
2362
2363	iput(sbi->s_vat_inode);
2364	unload_nls(sbi->s_nls_map);
2365	if (!sb_rdonly(sb))
2366		udf_close_lvid(sb);
2367	brelse(sbi->s_lvid_bh);
2368	udf_sb_free_partitions(sb);
2369	mutex_destroy(&sbi->s_alloc_mutex);
2370	kfree(sb->s_fs_info);
2371	sb->s_fs_info = NULL;
2372}
2373
2374static int udf_sync_fs(struct super_block *sb, int wait)
2375{
2376	struct udf_sb_info *sbi = UDF_SB(sb);
2377
2378	mutex_lock(&sbi->s_alloc_mutex);
2379	if (sbi->s_lvid_dirty) {
2380		struct buffer_head *bh = sbi->s_lvid_bh;
2381		struct logicalVolIntegrityDesc *lvid;
2382
2383		lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2384		udf_finalize_lvid(lvid);
2385
2386		/*
2387		 * Blockdevice will be synced later so we don't have to submit
2388		 * the buffer for IO
2389		 */
2390		mark_buffer_dirty(bh);
2391		sbi->s_lvid_dirty = 0;
2392	}
2393	mutex_unlock(&sbi->s_alloc_mutex);
2394
2395	return 0;
2396}
2397
2398static int udf_statfs(struct dentry *dentry, struct kstatfs *buf)
2399{
2400	struct super_block *sb = dentry->d_sb;
2401	struct udf_sb_info *sbi = UDF_SB(sb);
2402	struct logicalVolIntegrityDescImpUse *lvidiu;
2403	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
2404
2405	lvidiu = udf_sb_lvidiu(sb);
2406	buf->f_type = UDF_SUPER_MAGIC;
2407	buf->f_bsize = sb->s_blocksize;
2408	buf->f_blocks = sbi->s_partmaps[sbi->s_partition].s_partition_len;
2409	buf->f_bfree = udf_count_free(sb);
2410	buf->f_bavail = buf->f_bfree;
2411	/*
2412	 * Let's pretend each free block is also a free 'inode' since UDF does
2413	 * not have separate preallocated table of inodes.
2414	 */
2415	buf->f_files = (lvidiu != NULL ? (le32_to_cpu(lvidiu->numFiles) +
2416					  le32_to_cpu(lvidiu->numDirs)) : 0)
2417			+ buf->f_bfree;
2418	buf->f_ffree = buf->f_bfree;
2419	buf->f_namelen = UDF_NAME_LEN;
2420	buf->f_fsid = u64_to_fsid(id);
2421
2422	return 0;
2423}
2424
2425static unsigned int udf_count_free_bitmap(struct super_block *sb,
2426					  struct udf_bitmap *bitmap)
2427{
2428	struct buffer_head *bh = NULL;
2429	unsigned int accum = 0;
2430	int index;
2431	udf_pblk_t block = 0, newblock;
2432	struct kernel_lb_addr loc;
2433	uint32_t bytes;
2434	uint8_t *ptr;
2435	uint16_t ident;
2436	struct spaceBitmapDesc *bm;
2437
2438	loc.logicalBlockNum = bitmap->s_extPosition;
2439	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
2440	bh = udf_read_ptagged(sb, &loc, 0, &ident);
2441
2442	if (!bh) {
2443		udf_err(sb, "udf_count_free failed\n");
2444		goto out;
2445	} else if (ident != TAG_IDENT_SBD) {
2446		brelse(bh);
2447		udf_err(sb, "udf_count_free failed\n");
2448		goto out;
2449	}
2450
2451	bm = (struct spaceBitmapDesc *)bh->b_data;
2452	bytes = le32_to_cpu(bm->numOfBytes);
2453	index = sizeof(struct spaceBitmapDesc); /* offset in first block only */
2454	ptr = (uint8_t *)bh->b_data;
2455
2456	while (bytes > 0) {
2457		u32 cur_bytes = min_t(u32, bytes, sb->s_blocksize - index);
2458		accum += bitmap_weight((const unsigned long *)(ptr + index),
2459					cur_bytes * 8);
2460		bytes -= cur_bytes;
2461		if (bytes) {
2462			brelse(bh);
2463			newblock = udf_get_lb_pblock(sb, &loc, ++block);
2464			bh = sb_bread(sb, newblock);
2465			if (!bh) {
2466				udf_debug("read failed\n");
2467				goto out;
2468			}
2469			index = 0;
2470			ptr = (uint8_t *)bh->b_data;
2471		}
2472	}
2473	brelse(bh);
2474out:
2475	return accum;
2476}
2477
2478static unsigned int udf_count_free_table(struct super_block *sb,
2479					 struct inode *table)
2480{
2481	unsigned int accum = 0;
2482	uint32_t elen;
2483	struct kernel_lb_addr eloc;
2484	struct extent_position epos;
2485	int8_t etype;
2486
2487	mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
2488	epos.block = UDF_I(table)->i_location;
2489	epos.offset = sizeof(struct unallocSpaceEntry);
2490	epos.bh = NULL;
2491
2492	while (udf_next_aext(table, &epos, &eloc, &elen, &etype, 1) > 0)
2493		accum += (elen >> table->i_sb->s_blocksize_bits);
2494
2495	brelse(epos.bh);
2496	mutex_unlock(&UDF_SB(sb)->s_alloc_mutex);
2497
2498	return accum;
2499}
2500
2501static unsigned int udf_count_free(struct super_block *sb)
2502{
2503	unsigned int accum = 0;
2504	struct udf_sb_info *sbi = UDF_SB(sb);
2505	struct udf_part_map *map;
2506	unsigned int part = sbi->s_partition;
2507	int ptype = sbi->s_partmaps[part].s_partition_type;
2508
2509	if (ptype == UDF_METADATA_MAP25) {
2510		part = sbi->s_partmaps[part].s_type_specific.s_metadata.
2511							s_phys_partition_ref;
2512	} else if (ptype == UDF_VIRTUAL_MAP15 || ptype == UDF_VIRTUAL_MAP20) {
2513		/*
2514		 * Filesystems with VAT are append-only and we cannot write to
2515 		 * them. Let's just report 0 here.
2516		 */
2517		return 0;
2518	}
2519
2520	if (sbi->s_lvid_bh) {
2521		struct logicalVolIntegrityDesc *lvid =
2522			(struct logicalVolIntegrityDesc *)
2523			sbi->s_lvid_bh->b_data;
2524		if (le32_to_cpu(lvid->numOfPartitions) > part) {
2525			accum = le32_to_cpu(
2526					lvid->freeSpaceTable[part]);
2527			if (accum == 0xFFFFFFFF)
2528				accum = 0;
2529		}
2530	}
2531
2532	if (accum)
2533		return accum;
2534
2535	map = &sbi->s_partmaps[part];
2536	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
2537		accum += udf_count_free_bitmap(sb,
2538					       map->s_uspace.s_bitmap);
2539	}
2540	if (accum)
2541		return accum;
2542
2543	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
2544		accum += udf_count_free_table(sb,
2545					      map->s_uspace.s_table);
2546	}
2547	return accum;
2548}
2549
2550MODULE_AUTHOR("Ben Fennema");
2551MODULE_DESCRIPTION("Universal Disk Format Filesystem");
2552MODULE_LICENSE("GPL");
2553module_init(init_udf_fs)
2554module_exit(exit_udf_fs)