super.c

   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, part_map_count;
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
1465	part_map_count = le32_to_cpu(lvd->numPartitionMaps);
1466	if (part_map_count > table_len / sizeof(struct genericPartitionMap1)) {
1467		udf_err(sb, "error loading logical volume descriptor: "
1468			"Too many partition maps (%u > %u)\n", part_map_count,
1469			table_len / (unsigned)sizeof(struct genericPartitionMap1));
1470		ret = -EIO;
1471		goto out_bh;
1472	}
1473	ret = udf_sb_alloc_partition_maps(sb, part_map_count);
1474	if (ret)
1475		goto out_bh;
1476
1477	for (i = 0, offset = 0;
1478	     i < sbi->s_partitions && offset < table_len;
1479	     i++, offset += gpm->partitionMapLength) {
1480		struct udf_part_map *map = &sbi->s_partmaps[i];
1481		gpm = (struct genericPartitionMap *)
1482				&(lvd->partitionMaps[offset]);
1483		type = gpm->partitionMapType;
1484		if (type == 1) {
1485			struct genericPartitionMap1 *gpm1 =
1486				(struct genericPartitionMap1 *)gpm;
1487			map->s_partition_type = UDF_TYPE1_MAP15;
1488			map->s_volumeseqnum = le16_to_cpu(gpm1->volSeqNum);
1489			map->s_partition_num = le16_to_cpu(gpm1->partitionNum);
1490			map->s_partition_func = NULL;
1491		} else if (type == 2) {
1492			struct udfPartitionMap2 *upm2 =
1493						(struct udfPartitionMap2 *)gpm;
1494			if (!strncmp(upm2->partIdent.ident, UDF_ID_VIRTUAL,
1495						strlen(UDF_ID_VIRTUAL))) {
1496				u16 suf =
1497					le16_to_cpu(((__le16 *)upm2->partIdent.
1498							identSuffix)[0]);
1499				if (suf < 0x0200) {
1500					map->s_partition_type =
1501							UDF_VIRTUAL_MAP15;
1502					map->s_partition_func =
1503							udf_get_pblock_virt15;
1504				} else {
1505					map->s_partition_type =
1506							UDF_VIRTUAL_MAP20;
1507					map->s_partition_func =
1508							udf_get_pblock_virt20;
1509				}
1510			} else if (!strncmp(upm2->partIdent.ident,
1511						UDF_ID_SPARABLE,
1512						strlen(UDF_ID_SPARABLE))) {
1513				ret = udf_load_sparable_map(sb, map,
1514					(struct sparablePartitionMap *)gpm);
1515				if (ret < 0)
1516					goto out_bh;
1517			} else if (!strncmp(upm2->partIdent.ident,
1518						UDF_ID_METADATA,
1519						strlen(UDF_ID_METADATA))) {
1520				struct udf_meta_data *mdata =
1521					&map->s_type_specific.s_metadata;
1522				struct metadataPartitionMap *mdm =
1523						(struct metadataPartitionMap *)
1524						&(lvd->partitionMaps[offset]);
1525				udf_debug("Parsing Logical vol part %d type %u  id=%s\n",
1526					  i, type, UDF_ID_METADATA);
1527
1528				map->s_partition_type = UDF_METADATA_MAP25;
1529				map->s_partition_func = udf_get_pblock_meta25;
1530
1531				mdata->s_meta_file_loc   =
1532					le32_to_cpu(mdm->metadataFileLoc);
1533				mdata->s_mirror_file_loc =
1534					le32_to_cpu(mdm->metadataMirrorFileLoc);
1535				mdata->s_bitmap_file_loc =
1536					le32_to_cpu(mdm->metadataBitmapFileLoc);
1537				mdata->s_alloc_unit_size =
1538					le32_to_cpu(mdm->allocUnitSize);
1539				mdata->s_align_unit_size =
1540					le16_to_cpu(mdm->alignUnitSize);
1541				if (mdm->flags & 0x01)
1542					mdata->s_flags |= MF_DUPLICATE_MD;
1543
1544				udf_debug("Metadata Ident suffix=0x%x\n",
1545					  le16_to_cpu(*(__le16 *)
1546						      mdm->partIdent.identSuffix));
1547				udf_debug("Metadata part num=%u\n",
1548					  le16_to_cpu(mdm->partitionNum));
1549				udf_debug("Metadata part alloc unit size=%u\n",
1550					  le32_to_cpu(mdm->allocUnitSize));
1551				udf_debug("Metadata file loc=%u\n",
1552					  le32_to_cpu(mdm->metadataFileLoc));
1553				udf_debug("Mirror file loc=%u\n",
1554					  le32_to_cpu(mdm->metadataMirrorFileLoc));
1555				udf_debug("Bitmap file loc=%u\n",
1556					  le32_to_cpu(mdm->metadataBitmapFileLoc));
1557				udf_debug("Flags: %d %u\n",
1558					  mdata->s_flags, mdm->flags);
1559			} else {
1560				udf_debug("Unknown ident: %s\n",
1561					  upm2->partIdent.ident);
1562				continue;
1563			}
1564			map->s_volumeseqnum = le16_to_cpu(upm2->volSeqNum);
1565			map->s_partition_num = le16_to_cpu(upm2->partitionNum);
1566		}
1567		udf_debug("Partition (%d:%u) type %u on volume %u\n",
1568			  i, map->s_partition_num, type, map->s_volumeseqnum);
1569	}
1570
1571	if (fileset) {
1572		struct long_ad *la = (struct long_ad *)&(lvd->logicalVolContentsUse[0]);
1573
1574		*fileset = lelb_to_cpu(la->extLocation);
1575		udf_debug("FileSet found in LogicalVolDesc at block=%u, partition=%u\n",
1576			  fileset->logicalBlockNum,
1577			  fileset->partitionReferenceNum);
1578	}
1579	if (lvd->integritySeqExt.extLength)
1580		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
1581	ret = 0;
1582
1583	if (!sbi->s_lvid_bh) {
1584		/* We can't generate unique IDs without a valid LVID */
1585		if (sb_rdonly(sb)) {
1586			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
1587		} else {
1588			udf_warn(sb, "Damaged or missing LVID, forcing "
1589				     "readonly mount\n");
1590			ret = -EACCES;
1591		}
1592	}
1593out_bh:
1594	brelse(bh);
1595	return ret;
1596}
1597
1598static bool udf_lvid_valid(struct super_block *sb,
1599			   struct logicalVolIntegrityDesc *lvid)
1600{
1601	u32 parts, impuselen;
1602
1603	parts = le32_to_cpu(lvid->numOfPartitions);
1604	impuselen = le32_to_cpu(lvid->lengthOfImpUse);
1605	if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
1606	    sizeof(struct logicalVolIntegrityDesc) + impuselen +
1607	    2 * parts * sizeof(u32) > sb->s_blocksize)
1608		return false;
1609	return true;
1610}
1611
1612/*
1613 * Find the prevailing Logical Volume Integrity Descriptor.
1614 */
1615static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_ad loc)
1616{
1617	struct buffer_head *bh, *final_bh;
1618	uint16_t ident;
1619	struct udf_sb_info *sbi = UDF_SB(sb);
1620	struct logicalVolIntegrityDesc *lvid;
1621	int indirections = 0;
1622
1623	while (++indirections <= UDF_MAX_LVID_NESTING) {
1624		final_bh = NULL;
1625		while (loc.extLength > 0 &&
1626			(bh = udf_read_tagged(sb, loc.extLocation,
1627					loc.extLocation, &ident))) {
1628			if (ident != TAG_IDENT_LVID) {
1629				brelse(bh);
1630				break;
1631			}
1632
1633			brelse(final_bh);
1634			final_bh = bh;
1635
1636			loc.extLength -= sb->s_blocksize;
1637			loc.extLocation++;
1638		}
1639
1640		if (!final_bh)
1641			return;
1642
1643		lvid = (struct logicalVolIntegrityDesc *)final_bh->b_data;
1644		if (udf_lvid_valid(sb, lvid)) {
1645			brelse(sbi->s_lvid_bh);
1646			sbi->s_lvid_bh = final_bh;
1647		} else {
1648			udf_warn(sb, "Corrupted LVID (parts=%u, impuselen=%u), "
1649				 "ignoring.\n",
1650				 le32_to_cpu(lvid->numOfPartitions),
1651				 le32_to_cpu(lvid->lengthOfImpUse));
1652		}
1653
1654		if (lvid->nextIntegrityExt.extLength == 0)
1655			return;
1656
1657		loc = leea_to_cpu(lvid->nextIntegrityExt);
1658	}
1659
1660	udf_warn(sb, "Too many LVID indirections (max %u), ignoring.\n",
1661		UDF_MAX_LVID_NESTING);
1662	brelse(sbi->s_lvid_bh);
1663	sbi->s_lvid_bh = NULL;
1664}
1665
1666/*
1667 * Step for reallocation of table of partition descriptor sequence numbers.
1668 * Must be power of 2.
1669 */
1670#define PART_DESC_ALLOC_STEP 32
1671
1672struct part_desc_seq_scan_data {
1673	struct udf_vds_record rec;
1674	u32 partnum;
1675};
1676
1677struct desc_seq_scan_data {
1678	struct udf_vds_record vds[VDS_POS_LENGTH];
1679	unsigned int size_part_descs;
1680	unsigned int num_part_descs;
1681	struct part_desc_seq_scan_data *part_descs_loc;
1682};
1683
1684static struct udf_vds_record *handle_partition_descriptor(
1685				struct buffer_head *bh,
1686				struct desc_seq_scan_data *data)
1687{
1688	struct partitionDesc *desc = (struct partitionDesc *)bh->b_data;
1689	int partnum;
1690	int i;
1691
1692	partnum = le16_to_cpu(desc->partitionNumber);
1693	for (i = 0; i < data->num_part_descs; i++)
1694		if (partnum == data->part_descs_loc[i].partnum)
1695			return &(data->part_descs_loc[i].rec);
1696	if (data->num_part_descs >= data->size_part_descs) {
1697		struct part_desc_seq_scan_data *new_loc;
1698		unsigned int new_size = ALIGN(partnum, PART_DESC_ALLOC_STEP);
1699
1700		new_loc = kcalloc(new_size, sizeof(*new_loc), GFP_KERNEL);
1701		if (!new_loc)
1702			return ERR_PTR(-ENOMEM);
1703		memcpy(new_loc, data->part_descs_loc,
1704		       data->size_part_descs * sizeof(*new_loc));
1705		kfree(data->part_descs_loc);
1706		data->part_descs_loc = new_loc;
1707		data->size_part_descs = new_size;
1708	}
1709	return &(data->part_descs_loc[data->num_part_descs++].rec);
1710}
1711
1712
1713static struct udf_vds_record *get_volume_descriptor_record(uint16_t ident,
1714		struct buffer_head *bh, struct desc_seq_scan_data *data)
1715{
1716	switch (ident) {
1717	case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1718		return &(data->vds[VDS_POS_PRIMARY_VOL_DESC]);
1719	case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1720		return &(data->vds[VDS_POS_IMP_USE_VOL_DESC]);
1721	case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1722		return &(data->vds[VDS_POS_LOGICAL_VOL_DESC]);
1723	case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1724		return &(data->vds[VDS_POS_UNALLOC_SPACE_DESC]);
1725	case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1726		return handle_partition_descriptor(bh, data);
1727	}
1728	return NULL;
1729}
1730
1731/*
1732 * Process a main/reserve volume descriptor sequence.
1733 *   @block		First block of first extent of the sequence.
1734 *   @lastblock		Lastblock of first extent of the sequence.
1735 *   @fileset		There we store extent containing root fileset
1736 *
1737 * Returns <0 on error, 0 on success. -EAGAIN is special - try next descriptor
1738 * sequence
1739 */
1740static noinline int udf_process_sequence(
1741		struct super_block *sb,
1742		sector_t block, sector_t lastblock,
1743		struct kernel_lb_addr *fileset)
1744{
1745	struct buffer_head *bh = NULL;
1746	struct udf_vds_record *curr;
1747	struct generic_desc *gd;
1748	struct volDescPtr *vdp;
1749	bool done = false;
1750	uint32_t vdsn;
1751	uint16_t ident;
1752	int ret;
1753	unsigned int indirections = 0;
1754	struct desc_seq_scan_data data;
1755	unsigned int i;
1756
1757	memset(data.vds, 0, sizeof(struct udf_vds_record) * VDS_POS_LENGTH);
1758	data.size_part_descs = PART_DESC_ALLOC_STEP;
1759	data.num_part_descs = 0;
1760	data.part_descs_loc = kcalloc(data.size_part_descs,
1761				      sizeof(*data.part_descs_loc),
1762				      GFP_KERNEL);
1763	if (!data.part_descs_loc)
1764		return -ENOMEM;
1765
1766	/*
1767	 * Read the main descriptor sequence and find which descriptors
1768	 * are in it.
1769	 */
1770	for (; (!done && block <= lastblock); block++) {
1771		bh = udf_read_tagged(sb, block, block, &ident);
1772		if (!bh)
1773			break;
1774
1775		/* Process each descriptor (ISO 13346 3/8.3-8.4) */
1776		gd = (struct generic_desc *)bh->b_data;
1777		vdsn = le32_to_cpu(gd->volDescSeqNum);
1778		switch (ident) {
1779		case TAG_IDENT_VDP: /* ISO 13346 3/10.3 */
1780			if (++indirections > UDF_MAX_TD_NESTING) {
1781				udf_err(sb, "too many Volume Descriptor "
1782					"Pointers (max %u supported)\n",
1783					UDF_MAX_TD_NESTING);
1784				brelse(bh);
1785				ret = -EIO;
1786				goto out;
1787			}
1788
1789			vdp = (struct volDescPtr *)bh->b_data;
1790			block = le32_to_cpu(vdp->nextVolDescSeqExt.extLocation);
1791			lastblock = le32_to_cpu(
1792				vdp->nextVolDescSeqExt.extLength) >>
1793				sb->s_blocksize_bits;
1794			lastblock += block - 1;
1795			/* For loop is going to increment 'block' again */
1796			block--;
1797			break;
1798		case TAG_IDENT_PVD: /* ISO 13346 3/10.1 */
1799		case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
1800		case TAG_IDENT_LVD: /* ISO 13346 3/10.6 */
1801		case TAG_IDENT_USD: /* ISO 13346 3/10.8 */
1802		case TAG_IDENT_PD: /* ISO 13346 3/10.5 */
1803			curr = get_volume_descriptor_record(ident, bh, &data);
1804			if (IS_ERR(curr)) {
1805				brelse(bh);
1806				ret = PTR_ERR(curr);
1807				goto out;
1808			}
1809			/* Descriptor we don't care about? */
1810			if (!curr)
1811				break;
1812			if (vdsn >= curr->volDescSeqNum) {
1813				curr->volDescSeqNum = vdsn;
1814				curr->block = block;
1815			}
1816			break;
1817		case TAG_IDENT_TD: /* ISO 13346 3/10.9 */
1818			done = true;
1819			break;
1820		}
1821		brelse(bh);
1822	}
1823	/*
1824	 * Now read interesting descriptors again and process them
1825	 * in a suitable order
1826	 */
1827	if (!data.vds[VDS_POS_PRIMARY_VOL_DESC].block) {
1828		udf_err(sb, "Primary Volume Descriptor not found!\n");
1829		ret = -EAGAIN;
1830		goto out;
1831	}
1832	ret = udf_load_pvoldesc(sb, data.vds[VDS_POS_PRIMARY_VOL_DESC].block);
1833	if (ret < 0)
1834		goto out;
1835
1836	if (data.vds[VDS_POS_LOGICAL_VOL_DESC].block) {
1837		ret = udf_load_logicalvol(sb,
1838				data.vds[VDS_POS_LOGICAL_VOL_DESC].block,
1839				fileset);
1840		if (ret < 0)
1841			goto out;
1842	}
1843
1844	/* Now handle prevailing Partition Descriptors */
1845	for (i = 0; i < data.num_part_descs; i++) {
1846		ret = udf_load_partdesc(sb, data.part_descs_loc[i].rec.block);
1847		if (ret < 0)
1848			goto out;
1849	}
1850	ret = 0;
1851out:
1852	kfree(data.part_descs_loc);
1853	return ret;
1854}
1855
1856/*
1857 * Load Volume Descriptor Sequence described by anchor in bh
1858 *
1859 * Returns <0 on error, 0 on success
1860 */
1861static int udf_load_sequence(struct super_block *sb, struct buffer_head *bh,
1862			     struct kernel_lb_addr *fileset)
1863{
1864	struct anchorVolDescPtr *anchor;
1865	sector_t main_s, main_e, reserve_s, reserve_e;
1866	int ret;
1867
1868	anchor = (struct anchorVolDescPtr *)bh->b_data;
1869
1870	/* Locate the main sequence */
1871	main_s = le32_to_cpu(anchor->mainVolDescSeqExt.extLocation);
1872	main_e = le32_to_cpu(anchor->mainVolDescSeqExt.extLength);
1873	main_e = main_e >> sb->s_blocksize_bits;
1874	main_e += main_s - 1;
1875
1876	/* Locate the reserve sequence */
1877	reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
1878	reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
1879	reserve_e = reserve_e >> sb->s_blocksize_bits;
1880	reserve_e += reserve_s - 1;
1881
1882	/* Process the main & reserve sequences */
1883	/* responsible for finding the PartitionDesc(s) */
1884	ret = udf_process_sequence(sb, main_s, main_e, fileset);
1885	if (ret != -EAGAIN)
1886		return ret;
1887	udf_sb_free_partitions(sb);
1888	ret = udf_process_sequence(sb, reserve_s, reserve_e, fileset);
1889	if (ret < 0) {
1890		udf_sb_free_partitions(sb);
1891		/* No sequence was OK, return -EIO */
1892		if (ret == -EAGAIN)
1893			ret = -EIO;
1894	}
1895	return ret;
1896}
1897
1898/*
1899 * Check whether there is an anchor block in the given block and
1900 * load Volume Descriptor Sequence if so.
1901 *
1902 * Returns <0 on error, 0 on success, -EAGAIN is special - try next anchor
1903 * block
1904 */
1905static int udf_check_anchor_block(struct super_block *sb, sector_t block,
1906				  struct kernel_lb_addr *fileset)
1907{
1908	struct buffer_head *bh;
1909	uint16_t ident;
1910	int ret;
1911
1912	bh = udf_read_tagged(sb, block, block, &ident);
1913	if (!bh)
1914		return -EAGAIN;
1915	if (ident != TAG_IDENT_AVDP) {
1916		brelse(bh);
1917		return -EAGAIN;
1918	}
1919	ret = udf_load_sequence(sb, bh, fileset);
1920	brelse(bh);
1921	return ret;
1922}
1923
1924/*
1925 * Search for an anchor volume descriptor pointer.
1926 *
1927 * Returns < 0 on error, 0 on success. -EAGAIN is special - try next set
1928 * of anchors.
1929 */
1930static int udf_scan_anchors(struct super_block *sb, udf_pblk_t *lastblock,
1931			    struct kernel_lb_addr *fileset)
1932{
1933	udf_pblk_t last[6];
1934	int i;
1935	struct udf_sb_info *sbi = UDF_SB(sb);
1936	int last_count = 0;
1937	int ret;
1938
1939	/* First try user provided anchor */
1940	if (sbi->s_anchor) {
1941		ret = udf_check_anchor_block(sb, sbi->s_anchor, fileset);
1942		if (ret != -EAGAIN)
1943			return ret;
1944	}
1945	/*
1946	 * according to spec, anchor is in either:
1947	 *     block 256
1948	 *     lastblock-256
1949	 *     lastblock
1950	 *  however, if the disc isn't closed, it could be 512.
1951	 */
1952	ret = udf_check_anchor_block(sb, sbi->s_session + 256, fileset);
1953	if (ret != -EAGAIN)
1954		return ret;
1955	/*
1956	 * The trouble is which block is the last one. Drives often misreport
1957	 * this so we try various possibilities.
1958	 */
1959	last[last_count++] = *lastblock;
1960	if (*lastblock >= 1)
1961		last[last_count++] = *lastblock - 1;
1962	last[last_count++] = *lastblock + 1;
1963	if (*lastblock >= 2)
1964		last[last_count++] = *lastblock - 2;
1965	if (*lastblock >= 150)
1966		last[last_count++] = *lastblock - 150;
1967	if (*lastblock >= 152)
1968		last[last_count++] = *lastblock - 152;
1969
1970	for (i = 0; i < last_count; i++) {
1971		if (last[i] >= sb_bdev_nr_blocks(sb))
1972			continue;
1973		ret = udf_check_anchor_block(sb, last[i], fileset);
1974		if (ret != -EAGAIN) {
1975			if (!ret)
1976				*lastblock = last[i];
1977			return ret;
1978		}
1979		if (last[i] < 256)
1980			continue;
1981		ret = udf_check_anchor_block(sb, last[i] - 256, fileset);
1982		if (ret != -EAGAIN) {
1983			if (!ret)
1984				*lastblock = last[i];
1985			return ret;
1986		}
1987	}
1988
1989	/* Finally try block 512 in case media is open */
1990	return udf_check_anchor_block(sb, sbi->s_session + 512, fileset);
1991}
1992
1993/*
1994 * Check Volume Structure Descriptor, find Anchor block and load Volume
1995 * Descriptor Sequence.
1996 *
1997 * Returns < 0 on error, 0 on success. -EAGAIN is special meaning anchor
1998 * block was not found.
1999 */
2000static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
2001			int silent, struct kernel_lb_addr *fileset)
2002{
2003	struct udf_sb_info *sbi = UDF_SB(sb);
2004	int nsr = 0;
2005	int ret;
2006
2007	if (!sb_set_blocksize(sb, uopt->blocksize)) {
2008		if (!silent)
2009			udf_warn(sb, "Bad block size\n");
2010		return -EINVAL;
2011	}
2012	sbi->s_last_block = uopt->lastblock;
2013	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_NOVRS)) {
2014		/* Check that it is NSR02 compliant */
2015		nsr = udf_check_vsd(sb);
2016		if (!nsr) {
2017			if (!silent)
2018				udf_warn(sb, "No VRS found\n");
2019			return -EINVAL;
2020		}
2021		if (nsr == -1)
2022			udf_debug("Failed to read sector at offset %d. "
2023				  "Assuming open disc. Skipping validity "
2024				  "check\n", VSD_FIRST_SECTOR_OFFSET);
2025		if (!sbi->s_last_block)
2026			sbi->s_last_block = udf_get_last_block(sb);
2027	} else {
2028		udf_debug("Validity check skipped because of novrs option\n");
2029	}
2030
2031	/* Look for anchor block and load Volume Descriptor Sequence */
2032	sbi->s_anchor = uopt->anchor;
2033	ret = udf_scan_anchors(sb, &sbi->s_last_block, fileset);
2034	if (ret < 0) {
2035		if (!silent && ret == -EAGAIN)
2036			udf_warn(sb, "No anchor found\n");
2037		return ret;
2038	}
2039	return 0;
2040}
2041
2042static void udf_finalize_lvid(struct logicalVolIntegrityDesc *lvid)
2043{
2044	struct timespec64 ts;
2045
2046	ktime_get_real_ts64(&ts);
2047	udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
2048	lvid->descTag.descCRC = cpu_to_le16(
2049		crc_itu_t(0, (char *)lvid + sizeof(struct tag),
2050			le16_to_cpu(lvid->descTag.descCRCLength)));
2051	lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
2052}
2053
2054static void udf_open_lvid(struct super_block *sb)
2055{
2056	struct udf_sb_info *sbi = UDF_SB(sb);
2057	struct buffer_head *bh = sbi->s_lvid_bh;
2058	struct logicalVolIntegrityDesc *lvid;
2059	struct logicalVolIntegrityDescImpUse *lvidiu;
2060
2061	if (!bh)
2062		return;
2063	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2064	lvidiu = udf_sb_lvidiu(sb);
2065	if (!lvidiu)
2066		return;
2067
2068	mutex_lock(&sbi->s_alloc_mutex);
2069	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2070	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2071	if (le32_to_cpu(lvid->integrityType) == LVID_INTEGRITY_TYPE_CLOSE)
2072		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
2073	else
2074		UDF_SET_FLAG(sb, UDF_FLAG_INCONSISTENT);
2075
2076	udf_finalize_lvid(lvid);
2077	mark_buffer_dirty(bh);
2078	sbi->s_lvid_dirty = 0;
2079	mutex_unlock(&sbi->s_alloc_mutex);
2080	/* Make opening of filesystem visible on the media immediately */
2081	sync_dirty_buffer(bh);
2082}
2083
2084static void udf_close_lvid(struct super_block *sb)
2085{
2086	struct udf_sb_info *sbi = UDF_SB(sb);
2087	struct buffer_head *bh = sbi->s_lvid_bh;
2088	struct logicalVolIntegrityDesc *lvid;
2089	struct logicalVolIntegrityDescImpUse *lvidiu;
2090
2091	if (!bh)
2092		return;
2093	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2094	lvidiu = udf_sb_lvidiu(sb);
2095	if (!lvidiu)
2096		return;
2097
2098	mutex_lock(&sbi->s_alloc_mutex);
2099	lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
2100	lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
2101	if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
2102		lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
2103	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
2104		lvidiu->minUDFReadRev = cpu_to_le16(sbi->s_udfrev);
2105	if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFWriteRev))
2106		lvidiu->minUDFWriteRev = cpu_to_le16(sbi->s_udfrev);
2107	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_INCONSISTENT))
2108		lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);
2109
2110	/*
2111	 * We set buffer uptodate unconditionally here to avoid spurious
2112	 * warnings from mark_buffer_dirty() when previous EIO has marked
2113	 * the buffer as !uptodate
2114	 */
2115	set_buffer_uptodate(bh);
2116	udf_finalize_lvid(lvid);
2117	mark_buffer_dirty(bh);
2118	sbi->s_lvid_dirty = 0;
2119	mutex_unlock(&sbi->s_alloc_mutex);
2120	/* Make closing of filesystem visible on the media immediately */
2121	sync_dirty_buffer(bh);
2122}
2123
2124u64 lvid_get_unique_id(struct super_block *sb)
2125{
2126	struct buffer_head *bh;
2127	struct udf_sb_info *sbi = UDF_SB(sb);
2128	struct logicalVolIntegrityDesc *lvid;
2129	struct logicalVolHeaderDesc *lvhd;
2130	u64 uniqueID;
2131	u64 ret;
2132
2133	bh = sbi->s_lvid_bh;
2134	if (!bh)
2135		return 0;
2136
2137	lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2138	lvhd = (struct logicalVolHeaderDesc *)lvid->logicalVolContentsUse;
2139
2140	mutex_lock(&sbi->s_alloc_mutex);
2141	ret = uniqueID = le64_to_cpu(lvhd->uniqueID);
2142	if (!(++uniqueID & 0xFFFFFFFF))
2143		uniqueID += 16;
2144	lvhd->uniqueID = cpu_to_le64(uniqueID);
2145	udf_updated_lvid(sb);
2146	mutex_unlock(&sbi->s_alloc_mutex);
2147
2148	return ret;
2149}
2150
2151static int udf_fill_super(struct super_block *sb, struct fs_context *fc)
2152{
2153	int ret = -EINVAL;
2154	struct inode *inode = NULL;
2155	struct udf_options *uopt = fc->fs_private;
2156	struct kernel_lb_addr rootdir, fileset;
2157	struct udf_sb_info *sbi;
2158	bool lvid_open = false;
2159	int silent = fc->sb_flags & SB_SILENT;
2160
2161	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2162	if (!sbi)
2163		return -ENOMEM;
2164
2165	sb->s_fs_info = sbi;
2166
2167	mutex_init(&sbi->s_alloc_mutex);
2168
2169	fileset.logicalBlockNum = 0xFFFFFFFF;
2170	fileset.partitionReferenceNum = 0xFFFF;
2171
2172	sbi->s_flags = uopt->flags;
2173	sbi->s_uid = uopt->uid;
2174	sbi->s_gid = uopt->gid;
2175	sbi->s_umask = uopt->umask;
2176	sbi->s_fmode = uopt->fmode;
2177	sbi->s_dmode = uopt->dmode;
2178	sbi->s_nls_map = uopt->nls_map;
2179	uopt->nls_map = NULL;
2180	rwlock_init(&sbi->s_cred_lock);
2181
2182	if (uopt->session == 0xFFFFFFFF)
2183		sbi->s_session = udf_get_last_session(sb);
2184	else
2185		sbi->s_session = uopt->session;
2186
2187	udf_debug("Multi-session=%d\n", sbi->s_session);
2188
2189	/* Fill in the rest of the superblock */
2190	sb->s_op = &udf_sb_ops;
2191	sb->s_export_op = &udf_export_ops;
2192
2193	sb->s_magic = UDF_SUPER_MAGIC;
2194	sb->s_time_gran = 1000;
2195
2196	if (uopt->flags & (1 << UDF_FLAG_BLOCKSIZE_SET)) {
2197		ret = udf_load_vrs(sb, uopt, silent, &fileset);
2198	} else {
2199		uopt->blocksize = bdev_logical_block_size(sb->s_bdev);
2200		while (uopt->blocksize <= 4096) {
2201			ret = udf_load_vrs(sb, uopt, silent, &fileset);
2202			if (ret < 0) {
2203				if (!silent && ret != -EACCES) {
2204					pr_notice("Scanning with blocksize %u failed\n",
2205						  uopt->blocksize);
2206				}
2207				brelse(sbi->s_lvid_bh);
2208				sbi->s_lvid_bh = NULL;
2209				/*
2210				 * EACCES is special - we want to propagate to
2211				 * upper layers that we cannot handle RW mount.
2212				 */
2213				if (ret == -EACCES)
2214					break;
2215			} else
2216				break;
2217
2218			uopt->blocksize <<= 1;
2219		}
2220	}
2221	if (ret < 0) {
2222		if (ret == -EAGAIN) {
2223			udf_warn(sb, "No partition found (1)\n");
2224			ret = -EINVAL;
2225		}
2226		goto error_out;
2227	}
2228
2229	udf_debug("Lastblock=%u\n", sbi->s_last_block);
2230
2231	if (sbi->s_lvid_bh) {
2232		struct logicalVolIntegrityDescImpUse *lvidiu =
2233							udf_sb_lvidiu(sb);
2234		uint16_t minUDFReadRev;
2235		uint16_t minUDFWriteRev;
2236
2237		if (!lvidiu) {
2238			ret = -EINVAL;
2239			goto error_out;
2240		}
2241		minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev);
2242		minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev);
2243		if (minUDFReadRev > UDF_MAX_READ_VERSION) {
2244			udf_err(sb, "minUDFReadRev=%x (max is %x)\n",
2245				minUDFReadRev,
2246				UDF_MAX_READ_VERSION);
2247			ret = -EINVAL;
2248			goto error_out;
2249		} else if (minUDFWriteRev > UDF_MAX_WRITE_VERSION) {
2250			if (!sb_rdonly(sb)) {
2251				ret = -EACCES;
2252				goto error_out;
2253			}
2254			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2255		}
2256
2257		sbi->s_udfrev = minUDFWriteRev;
2258
2259		if (minUDFReadRev >= UDF_VERS_USE_EXTENDED_FE)
2260			UDF_SET_FLAG(sb, UDF_FLAG_USE_EXTENDED_FE);
2261		if (minUDFReadRev >= UDF_VERS_USE_STREAMS)
2262			UDF_SET_FLAG(sb, UDF_FLAG_USE_STREAMS);
2263	}
2264
2265	if (!sbi->s_partitions) {
2266		udf_warn(sb, "No partition found (2)\n");
2267		ret = -EINVAL;
2268		goto error_out;
2269	}
2270
2271	if (sbi->s_partmaps[sbi->s_partition].s_partition_flags &
2272			UDF_PART_FLAG_READ_ONLY) {
2273		if (!sb_rdonly(sb)) {
2274			ret = -EACCES;
2275			goto error_out;
2276		}
2277		UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
2278	}
2279
2280	ret = udf_find_fileset(sb, &fileset, &rootdir);
2281	if (ret < 0) {
2282		udf_warn(sb, "No fileset found\n");
2283		goto error_out;
2284	}
2285
2286	if (!silent) {
2287		struct timestamp ts;
2288		udf_time_to_disk_stamp(&ts, sbi->s_record_time);
2289		udf_info("Mounting volume '%s', timestamp %04u/%02u/%02u %02u:%02u (%x)\n",
2290			 sbi->s_volume_ident,
2291			 le16_to_cpu(ts.year), ts.month, ts.day,
2292			 ts.hour, ts.minute, le16_to_cpu(ts.typeAndTimezone));
2293	}
2294	if (!sb_rdonly(sb)) {
2295		udf_open_lvid(sb);
2296		lvid_open = true;
2297	}
2298
2299	/* Assign the root inode */
2300	/* assign inodes by physical block number */
2301	/* perhaps it's not extensible enough, but for now ... */
2302	inode = udf_iget(sb, &rootdir);
2303	if (IS_ERR(inode)) {
2304		udf_err(sb, "Error in udf_iget, block=%u, partition=%u\n",
2305		       rootdir.logicalBlockNum, rootdir.partitionReferenceNum);
2306		ret = PTR_ERR(inode);
2307		goto error_out;
2308	}
2309
2310	/* Allocate a dentry for the root inode */
2311	sb->s_root = d_make_root(inode);
2312	if (!sb->s_root) {
2313		udf_err(sb, "Couldn't allocate root dentry\n");
2314		ret = -ENOMEM;
2315		goto error_out;
2316	}
2317	sb->s_maxbytes = UDF_MAX_FILESIZE;
2318	sb->s_max_links = UDF_MAX_LINKS;
2319	return 0;
2320
2321error_out:
2322	iput(sbi->s_vat_inode);
2323	unload_nls(uopt->nls_map);
2324	if (lvid_open)
2325		udf_close_lvid(sb);
2326	brelse(sbi->s_lvid_bh);
2327	udf_sb_free_partitions(sb);
2328	kfree(sbi);
2329	sb->s_fs_info = NULL;
2330
2331	return ret;
2332}
2333
2334void _udf_err(struct super_block *sb, const char *function,
2335	      const char *fmt, ...)
2336{
2337	struct va_format vaf;
2338	va_list args;
2339
2340	va_start(args, fmt);
2341
2342	vaf.fmt = fmt;
2343	vaf.va = &args;
2344
2345	pr_err("error (device %s): %s: %pV", sb->s_id, function, &vaf);
2346
2347	va_end(args);
2348}
2349
2350void _udf_warn(struct super_block *sb, const char *function,
2351	       const char *fmt, ...)
2352{
2353	struct va_format vaf;
2354	va_list args;
2355
2356	va_start(args, fmt);
2357
2358	vaf.fmt = fmt;
2359	vaf.va = &args;
2360
2361	pr_warn("warning (device %s): %s: %pV", sb->s_id, function, &vaf);
2362
2363	va_end(args);
2364}
2365
2366static void udf_put_super(struct super_block *sb)
2367{
2368	struct udf_sb_info *sbi;
2369
2370	sbi = UDF_SB(sb);
2371
2372	iput(sbi->s_vat_inode);
2373	unload_nls(sbi->s_nls_map);
2374	if (!sb_rdonly(sb))
2375		udf_close_lvid(sb);
2376	brelse(sbi->s_lvid_bh);
2377	udf_sb_free_partitions(sb);
2378	mutex_destroy(&sbi->s_alloc_mutex);
2379	kfree(sb->s_fs_info);
2380	sb->s_fs_info = NULL;
2381}
2382
2383static int udf_sync_fs(struct super_block *sb, int wait)
2384{
2385	struct udf_sb_info *sbi = UDF_SB(sb);
2386
2387	mutex_lock(&sbi->s_alloc_mutex);
2388	if (sbi->s_lvid_dirty) {
2389		struct buffer_head *bh = sbi->s_lvid_bh;
2390		struct logicalVolIntegrityDesc *lvid;
2391
2392		lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
2393		udf_finalize_lvid(lvid);
2394
2395		/*
2396		 * Blockdevice will be synced later so we don't have to submit
2397		 * the buffer for IO
2398		 */
2399		mark_buffer_dirty(bh);
2400		sbi->s_lvid_dirty = 0;
2401	}
2402	mutex_unlock(&sbi->s_alloc_mutex);
2403
2404	return 0;
2405}
2406
2407static int udf_statfs(struct dentry *dentry, struct kstatfs *buf)
2408{
2409	struct super_block *sb = dentry->d_sb;
2410	struct udf_sb_info *sbi = UDF_SB(sb);
2411	struct logicalVolIntegrityDescImpUse *lvidiu;
2412	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
2413
2414	lvidiu = udf_sb_lvidiu(sb);
2415	buf->f_type = UDF_SUPER_MAGIC;
2416	buf->f_bsize = sb->s_blocksize;
2417	buf->f_blocks = sbi->s_partmaps[sbi->s_partition].s_partition_len;
2418	buf->f_bfree = udf_count_free(sb);
2419	buf->f_bavail = buf->f_bfree;
2420	/*
2421	 * Let's pretend each free block is also a free 'inode' since UDF does
2422	 * not have separate preallocated table of inodes.
2423	 */
2424	buf->f_files = (lvidiu != NULL ? (le32_to_cpu(lvidiu->numFiles) +
2425					  le32_to_cpu(lvidiu->numDirs)) : 0)
2426			+ buf->f_bfree;
2427	buf->f_ffree = buf->f_bfree;
2428	buf->f_namelen = UDF_NAME_LEN;
2429	buf->f_fsid = u64_to_fsid(id);
2430
2431	return 0;
2432}
2433
2434static unsigned int udf_count_free_bitmap(struct super_block *sb,
2435					  struct udf_bitmap *bitmap)
2436{
2437	struct buffer_head *bh = NULL;
2438	unsigned int accum = 0;
2439	int index;
2440	udf_pblk_t block = 0, newblock;
2441	struct kernel_lb_addr loc;
2442	uint32_t bytes;
2443	uint8_t *ptr;
2444	uint16_t ident;
2445	struct spaceBitmapDesc *bm;
2446
2447	loc.logicalBlockNum = bitmap->s_extPosition;
2448	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
2449	bh = udf_read_ptagged(sb, &loc, 0, &ident);
2450
2451	if (!bh) {
2452		udf_err(sb, "udf_count_free failed\n");
2453		goto out;
2454	} else if (ident != TAG_IDENT_SBD) {
2455		brelse(bh);
2456		udf_err(sb, "udf_count_free failed\n");
2457		goto out;
2458	}
2459
2460	bm = (struct spaceBitmapDesc *)bh->b_data;
2461	bytes = le32_to_cpu(bm->numOfBytes);
2462	index = sizeof(struct spaceBitmapDesc); /* offset in first block only */
2463	ptr = (uint8_t *)bh->b_data;
2464
2465	while (bytes > 0) {
2466		u32 cur_bytes = min_t(u32, bytes, sb->s_blocksize - index);
2467		accum += bitmap_weight((const unsigned long *)(ptr + index),
2468					cur_bytes * 8);
2469		bytes -= cur_bytes;
2470		if (bytes) {
2471			brelse(bh);
2472			newblock = udf_get_lb_pblock(sb, &loc, ++block);
2473			bh = sb_bread(sb, newblock);
2474			if (!bh) {
2475				udf_debug("read failed\n");
2476				goto out;
2477			}
2478			index = 0;
2479			ptr = (uint8_t *)bh->b_data;
2480		}
2481	}
2482	brelse(bh);
2483out:
2484	return accum;
2485}
2486
2487static unsigned int udf_count_free_table(struct super_block *sb,
2488					 struct inode *table)
2489{
2490	unsigned int accum = 0;
2491	uint32_t elen;
2492	struct kernel_lb_addr eloc;
2493	struct extent_position epos;
2494	int8_t etype;
2495
2496	mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
2497	epos.block = UDF_I(table)->i_location;
2498	epos.offset = sizeof(struct unallocSpaceEntry);
2499	epos.bh = NULL;
2500
2501	while (udf_next_aext(table, &epos, &eloc, &elen, &etype, 1) > 0)
2502		accum += (elen >> table->i_sb->s_blocksize_bits);
2503
2504	brelse(epos.bh);
2505	mutex_unlock(&UDF_SB(sb)->s_alloc_mutex);
2506
2507	return accum;
2508}
2509
2510static unsigned int udf_count_free(struct super_block *sb)
2511{
2512	unsigned int accum = 0;
2513	struct udf_sb_info *sbi = UDF_SB(sb);
2514	struct udf_part_map *map;
2515	unsigned int part = sbi->s_partition;
2516	int ptype = sbi->s_partmaps[part].s_partition_type;
2517
2518	if (ptype == UDF_METADATA_MAP25) {
2519		part = sbi->s_partmaps[part].s_type_specific.s_metadata.
2520							s_phys_partition_ref;
2521	} else if (ptype == UDF_VIRTUAL_MAP15 || ptype == UDF_VIRTUAL_MAP20) {
2522		/*
2523		 * Filesystems with VAT are append-only and we cannot write to
2524 		 * them. Let's just report 0 here.
2525		 */
2526		return 0;
2527	}
2528
2529	if (sbi->s_lvid_bh) {
2530		struct logicalVolIntegrityDesc *lvid =
2531			(struct logicalVolIntegrityDesc *)
2532			sbi->s_lvid_bh->b_data;
2533		if (le32_to_cpu(lvid->numOfPartitions) > part) {
2534			accum = le32_to_cpu(
2535					lvid->freeSpaceTable[part]);
2536			if (accum == 0xFFFFFFFF)
2537				accum = 0;
2538		}
2539	}
2540
2541	if (accum)
2542		return accum;
2543
2544	map = &sbi->s_partmaps[part];
2545	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
2546		accum += udf_count_free_bitmap(sb,
2547					       map->s_uspace.s_bitmap);
2548	}
2549	if (accum)
2550		return accum;
2551
2552	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
2553		accum += udf_count_free_table(sb,
2554					      map->s_uspace.s_table);
2555	}
2556	return accum;
2557}
2558
2559MODULE_AUTHOR("Ben Fennema");
2560MODULE_DESCRIPTION("Universal Disk Format Filesystem");
2561MODULE_LICENSE("GPL");
2562module_init(init_udf_fs)
2563module_exit(exit_udf_fs)