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   1/*
   2 *  linux/fs/isofs/inode.c
   3 *
   4 *  (C) 1991  Linus Torvalds - minix filesystem
   5 *      1992, 1993, 1994  Eric Youngdale Modified for ISO 9660 filesystem.
   6 *      1994  Eberhard Mönkeberg - multi session handling.
   7 *      1995  Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
   8 *	1997  Gordon Chaffee - Joliet CDs
   9 *	1998  Eric Lammerts - ISO 9660 Level 3
  10 *	2004  Paul Serice - Inode Support pushed out from 4GB to 128GB
  11 *	2004  Paul Serice - NFS Export Operations
  12 */
  13
  14#include <linux/init.h>
  15#include <linux/module.h>
  16
  17#include <linux/slab.h>
  18#include <linux/cred.h>
  19#include <linux/nls.h>
  20#include <linux/ctype.h>
  21#include <linux/statfs.h>
  22#include <linux/cdrom.h>
  23#include <linux/parser.h>
  24#include <linux/mpage.h>
  25#include <linux/user_namespace.h>
  26#include <linux/seq_file.h>
  27
  28#include "isofs.h"
  29#include "zisofs.h"
  30
  31#define BEQUIET
  32
  33static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
  34static int isofs_dentry_cmpi(const struct dentry *dentry,
  35		unsigned int len, const char *str, const struct qstr *name);
  36
  37#ifdef CONFIG_JOLIET
  38static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
  39static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
  40static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
  41		unsigned int len, const char *str, const struct qstr *name);
  42static int isofs_dentry_cmp_ms(const struct dentry *dentry,
  43		unsigned int len, const char *str, const struct qstr *name);
  44#endif
  45
  46static void isofs_put_super(struct super_block *sb)
  47{
  48	struct isofs_sb_info *sbi = ISOFS_SB(sb);
  49
  50#ifdef CONFIG_JOLIET
  51	unload_nls(sbi->s_nls_iocharset);
  52#endif
  53
  54	kfree(sbi);
  55	sb->s_fs_info = NULL;
  56	return;
  57}
  58
  59static int isofs_read_inode(struct inode *, int relocated);
  60static int isofs_statfs (struct dentry *, struct kstatfs *);
  61static int isofs_show_options(struct seq_file *, struct dentry *);
  62
  63static struct kmem_cache *isofs_inode_cachep;
  64
  65static struct inode *isofs_alloc_inode(struct super_block *sb)
  66{
  67	struct iso_inode_info *ei;
  68	ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
  69	if (!ei)
  70		return NULL;
  71	return &ei->vfs_inode;
  72}
  73
  74static void isofs_i_callback(struct rcu_head *head)
  75{
  76	struct inode *inode = container_of(head, struct inode, i_rcu);
  77	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
  78}
  79
  80static void isofs_destroy_inode(struct inode *inode)
  81{
  82	call_rcu(&inode->i_rcu, isofs_i_callback);
  83}
  84
  85static void init_once(void *foo)
  86{
  87	struct iso_inode_info *ei = foo;
  88
  89	inode_init_once(&ei->vfs_inode);
  90}
  91
  92static int __init init_inodecache(void)
  93{
  94	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
  95					sizeof(struct iso_inode_info),
  96					0, (SLAB_RECLAIM_ACCOUNT|
  97					SLAB_MEM_SPREAD|SLAB_ACCOUNT),
  98					init_once);
  99	if (!isofs_inode_cachep)
 100		return -ENOMEM;
 101	return 0;
 102}
 103
 104static void destroy_inodecache(void)
 105{
 106	/*
 107	 * Make sure all delayed rcu free inodes are flushed before we
 108	 * destroy cache.
 109	 */
 110	rcu_barrier();
 111	kmem_cache_destroy(isofs_inode_cachep);
 112}
 113
 114static int isofs_remount(struct super_block *sb, int *flags, char *data)
 115{
 116	sync_filesystem(sb);
 117	if (!(*flags & SB_RDONLY))
 118		return -EROFS;
 119	return 0;
 120}
 121
 122static const struct super_operations isofs_sops = {
 123	.alloc_inode	= isofs_alloc_inode,
 124	.destroy_inode	= isofs_destroy_inode,
 125	.put_super	= isofs_put_super,
 126	.statfs		= isofs_statfs,
 127	.remount_fs	= isofs_remount,
 128	.show_options	= isofs_show_options,
 129};
 130
 131
 132static const struct dentry_operations isofs_dentry_ops[] = {
 133	{
 134		.d_hash		= isofs_hashi,
 135		.d_compare	= isofs_dentry_cmpi,
 136	},
 137#ifdef CONFIG_JOLIET
 138	{
 139		.d_hash		= isofs_hash_ms,
 140		.d_compare	= isofs_dentry_cmp_ms,
 141	},
 142	{
 143		.d_hash		= isofs_hashi_ms,
 144		.d_compare	= isofs_dentry_cmpi_ms,
 145	},
 146#endif
 147};
 148
 149struct iso9660_options{
 150	unsigned int rock:1;
 151	unsigned int joliet:1;
 152	unsigned int cruft:1;
 153	unsigned int hide:1;
 154	unsigned int showassoc:1;
 155	unsigned int nocompress:1;
 156	unsigned int overriderockperm:1;
 157	unsigned int uid_set:1;
 158	unsigned int gid_set:1;
 159	unsigned int utf8:1;
 160	unsigned char map;
 161	unsigned char check;
 162	unsigned int blocksize;
 163	umode_t fmode;
 164	umode_t dmode;
 165	kgid_t gid;
 166	kuid_t uid;
 167	char *iocharset;
 168	/* LVE */
 169	s32 session;
 170	s32 sbsector;
 171};
 172
 173/*
 174 * Compute the hash for the isofs name corresponding to the dentry.
 175 */
 176static int
 177isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
 178{
 179	const char *name;
 180	int len;
 181	char c;
 182	unsigned long hash;
 183
 184	len = qstr->len;
 185	name = qstr->name;
 186	if (ms) {
 187		while (len && name[len-1] == '.')
 188			len--;
 189	}
 190
 191	hash = init_name_hash(dentry);
 192	while (len--) {
 193		c = tolower(*name++);
 194		hash = partial_name_hash(c, hash);
 195	}
 196	qstr->hash = end_name_hash(hash);
 197
 198	return 0;
 199}
 200
 201/*
 202 * Compare of two isofs names.
 203 */
 204static int isofs_dentry_cmp_common(
 205		unsigned int len, const char *str,
 206		const struct qstr *name, int ms, int ci)
 207{
 208	int alen, blen;
 209
 210	/* A filename cannot end in '.' or we treat it like it has none */
 211	alen = name->len;
 212	blen = len;
 213	if (ms) {
 214		while (alen && name->name[alen-1] == '.')
 215			alen--;
 216		while (blen && str[blen-1] == '.')
 217			blen--;
 218	}
 219	if (alen == blen) {
 220		if (ci) {
 221			if (strncasecmp(name->name, str, alen) == 0)
 222				return 0;
 223		} else {
 224			if (strncmp(name->name, str, alen) == 0)
 225				return 0;
 226		}
 227	}
 228	return 1;
 229}
 230
 231static int
 232isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
 233{
 234	return isofs_hashi_common(dentry, qstr, 0);
 235}
 236
 237static int
 238isofs_dentry_cmpi(const struct dentry *dentry,
 239		unsigned int len, const char *str, const struct qstr *name)
 240{
 241	return isofs_dentry_cmp_common(len, str, name, 0, 1);
 242}
 243
 244#ifdef CONFIG_JOLIET
 245/*
 246 * Compute the hash for the isofs name corresponding to the dentry.
 247 */
 248static int
 249isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
 250{
 251	const char *name;
 252	int len;
 253
 254	len = qstr->len;
 255	name = qstr->name;
 256	if (ms) {
 257		while (len && name[len-1] == '.')
 258			len--;
 259	}
 260
 261	qstr->hash = full_name_hash(dentry, name, len);
 262
 263	return 0;
 264}
 265
 266static int
 267isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
 268{
 269	return isofs_hash_common(dentry, qstr, 1);
 270}
 271
 272static int
 273isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
 274{
 275	return isofs_hashi_common(dentry, qstr, 1);
 276}
 277
 278static int
 279isofs_dentry_cmp_ms(const struct dentry *dentry,
 280		unsigned int len, const char *str, const struct qstr *name)
 281{
 282	return isofs_dentry_cmp_common(len, str, name, 1, 0);
 283}
 284
 285static int
 286isofs_dentry_cmpi_ms(const struct dentry *dentry,
 287		unsigned int len, const char *str, const struct qstr *name)
 288{
 289	return isofs_dentry_cmp_common(len, str, name, 1, 1);
 290}
 291#endif
 292
 293enum {
 294	Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
 295	Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
 296	Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
 297	Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
 298};
 299
 300static const match_table_t tokens = {
 301	{Opt_norock, "norock"},
 302	{Opt_nojoliet, "nojoliet"},
 303	{Opt_unhide, "unhide"},
 304	{Opt_hide, "hide"},
 305	{Opt_showassoc, "showassoc"},
 306	{Opt_cruft, "cruft"},
 307	{Opt_utf8, "utf8"},
 308	{Opt_iocharset, "iocharset=%s"},
 309	{Opt_map_a, "map=acorn"},
 310	{Opt_map_a, "map=a"},
 311	{Opt_map_n, "map=normal"},
 312	{Opt_map_n, "map=n"},
 313	{Opt_map_o, "map=off"},
 314	{Opt_map_o, "map=o"},
 315	{Opt_session, "session=%u"},
 316	{Opt_sb, "sbsector=%u"},
 317	{Opt_check_r, "check=relaxed"},
 318	{Opt_check_r, "check=r"},
 319	{Opt_check_s, "check=strict"},
 320	{Opt_check_s, "check=s"},
 321	{Opt_uid, "uid=%u"},
 322	{Opt_gid, "gid=%u"},
 323	{Opt_mode, "mode=%u"},
 324	{Opt_dmode, "dmode=%u"},
 325	{Opt_overriderockperm, "overriderockperm"},
 326	{Opt_block, "block=%u"},
 327	{Opt_ignore, "conv=binary"},
 328	{Opt_ignore, "conv=b"},
 329	{Opt_ignore, "conv=text"},
 330	{Opt_ignore, "conv=t"},
 331	{Opt_ignore, "conv=mtext"},
 332	{Opt_ignore, "conv=m"},
 333	{Opt_ignore, "conv=auto"},
 334	{Opt_ignore, "conv=a"},
 335	{Opt_nocompress, "nocompress"},
 336	{Opt_err, NULL}
 337};
 338
 339static int parse_options(char *options, struct iso9660_options *popt)
 340{
 341	char *p;
 342	int option;
 343
 344	popt->map = 'n';
 345	popt->rock = 1;
 346	popt->joliet = 1;
 347	popt->cruft = 0;
 348	popt->hide = 0;
 349	popt->showassoc = 0;
 350	popt->check = 'u';		/* unset */
 351	popt->nocompress = 0;
 352	popt->blocksize = 1024;
 353	popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
 354	popt->uid_set = 0;
 355	popt->gid_set = 0;
 356	popt->gid = GLOBAL_ROOT_GID;
 357	popt->uid = GLOBAL_ROOT_UID;
 358	popt->iocharset = NULL;
 359	popt->utf8 = 0;
 360	popt->overriderockperm = 0;
 361	popt->session=-1;
 362	popt->sbsector=-1;
 363	if (!options)
 364		return 1;
 365
 366	while ((p = strsep(&options, ",")) != NULL) {
 367		int token;
 368		substring_t args[MAX_OPT_ARGS];
 369		unsigned n;
 370
 371		if (!*p)
 372			continue;
 373
 374		token = match_token(p, tokens, args);
 375		switch (token) {
 376		case Opt_norock:
 377			popt->rock = 0;
 378			break;
 379		case Opt_nojoliet:
 380			popt->joliet = 0;
 381			break;
 382		case Opt_hide:
 383			popt->hide = 1;
 384			break;
 385		case Opt_unhide:
 386		case Opt_showassoc:
 387			popt->showassoc = 1;
 388			break;
 389		case Opt_cruft:
 390			popt->cruft = 1;
 391			break;
 392		case Opt_utf8:
 393			popt->utf8 = 1;
 394			break;
 395#ifdef CONFIG_JOLIET
 396		case Opt_iocharset:
 397			kfree(popt->iocharset);
 398			popt->iocharset = match_strdup(&args[0]);
 399			if (!popt->iocharset)
 400				return 0;
 401			break;
 402#endif
 403		case Opt_map_a:
 404			popt->map = 'a';
 405			break;
 406		case Opt_map_o:
 407			popt->map = 'o';
 408			break;
 409		case Opt_map_n:
 410			popt->map = 'n';
 411			break;
 412		case Opt_session:
 413			if (match_int(&args[0], &option))
 414				return 0;
 415			n = option;
 416			/*
 417			 * Track numbers are supposed to be in range 1-99, the
 418			 * mount option starts indexing at 0.
 419			 */
 420			if (n >= 99)
 421				return 0;
 422			popt->session = n + 1;
 423			break;
 424		case Opt_sb:
 425			if (match_int(&args[0], &option))
 426				return 0;
 427			popt->sbsector = option;
 428			break;
 429		case Opt_check_r:
 430			popt->check = 'r';
 431			break;
 432		case Opt_check_s:
 433			popt->check = 's';
 434			break;
 435		case Opt_ignore:
 436			break;
 437		case Opt_uid:
 438			if (match_int(&args[0], &option))
 439				return 0;
 440			popt->uid = make_kuid(current_user_ns(), option);
 441			if (!uid_valid(popt->uid))
 442				return 0;
 443			popt->uid_set = 1;
 444			break;
 445		case Opt_gid:
 446			if (match_int(&args[0], &option))
 447				return 0;
 448			popt->gid = make_kgid(current_user_ns(), option);
 449			if (!gid_valid(popt->gid))
 450				return 0;
 451			popt->gid_set = 1;
 452			break;
 453		case Opt_mode:
 454			if (match_int(&args[0], &option))
 455				return 0;
 456			popt->fmode = option;
 457			break;
 458		case Opt_dmode:
 459			if (match_int(&args[0], &option))
 460				return 0;
 461			popt->dmode = option;
 462			break;
 463		case Opt_overriderockperm:
 464			popt->overriderockperm = 1;
 465			break;
 466		case Opt_block:
 467			if (match_int(&args[0], &option))
 468				return 0;
 469			n = option;
 470			if (n != 512 && n != 1024 && n != 2048)
 471				return 0;
 472			popt->blocksize = n;
 473			break;
 474		case Opt_nocompress:
 475			popt->nocompress = 1;
 476			break;
 477		default:
 478			return 0;
 479		}
 480	}
 481	return 1;
 482}
 483
 484/*
 485 * Display the mount options in /proc/mounts.
 486 */
 487static int isofs_show_options(struct seq_file *m, struct dentry *root)
 488{
 489	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
 490
 491	if (!sbi->s_rock)		seq_puts(m, ",norock");
 492	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
 493	if (sbi->s_cruft)		seq_puts(m, ",cruft");
 494	if (sbi->s_hide)		seq_puts(m, ",hide");
 495	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
 496	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
 497	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
 498	if (sbi->s_utf8)		seq_puts(m, ",utf8");
 499
 500	if (sbi->s_check)		seq_printf(m, ",check=%c", sbi->s_check);
 501	if (sbi->s_mapping)		seq_printf(m, ",map=%c", sbi->s_mapping);
 502	if (sbi->s_session != 255)	seq_printf(m, ",session=%u", sbi->s_session - 1);
 503	if (sbi->s_sbsector != -1)	seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
 504
 505	if (root->d_sb->s_blocksize != 1024)
 506		seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
 507
 508	if (sbi->s_uid_set)
 509		seq_printf(m, ",uid=%u",
 510			   from_kuid_munged(&init_user_ns, sbi->s_uid));
 511	if (sbi->s_gid_set)
 512		seq_printf(m, ",gid=%u",
 513			   from_kgid_munged(&init_user_ns, sbi->s_gid));
 514
 515	if (sbi->s_dmode != ISOFS_INVALID_MODE)
 516		seq_printf(m, ",dmode=%o", sbi->s_dmode);
 517	if (sbi->s_fmode != ISOFS_INVALID_MODE)
 518		seq_printf(m, ",fmode=%o", sbi->s_fmode);
 519
 520#ifdef CONFIG_JOLIET
 521	if (sbi->s_nls_iocharset &&
 522	    strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
 523		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
 524#endif
 525	return 0;
 526}
 527
 528/*
 529 * look if the driver can tell the multi session redirection value
 530 *
 531 * don't change this if you don't know what you do, please!
 532 * Multisession is legal only with XA disks.
 533 * A non-XA disk with more than one volume descriptor may do it right, but
 534 * usually is written in a nowhere standardized "multi-partition" manner.
 535 * Multisession uses absolute addressing (solely the first frame of the whole
 536 * track is #0), multi-partition uses relative addressing (each first frame of
 537 * each track is #0), and a track is not a session.
 538 *
 539 * A broken CDwriter software or drive firmware does not set new standards,
 540 * at least not if conflicting with the existing ones.
 541 *
 542 * emoenke@gwdg.de
 543 */
 544#define WE_OBEY_THE_WRITTEN_STANDARDS 1
 545
 546static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
 547{
 548	struct cdrom_multisession ms_info;
 549	unsigned int vol_desc_start;
 550	struct block_device *bdev = sb->s_bdev;
 551	int i;
 552
 553	vol_desc_start=0;
 554	ms_info.addr_format=CDROM_LBA;
 555	if (session > 0) {
 556		struct cdrom_tocentry Te;
 557		Te.cdte_track=session;
 558		Te.cdte_format=CDROM_LBA;
 559		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
 560		if (!i) {
 561			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
 562				session, Te.cdte_addr.lba,
 563				Te.cdte_ctrl&CDROM_DATA_TRACK);
 564			if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
 565				return Te.cdte_addr.lba;
 566		}
 567
 568		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
 569	}
 570	i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
 571	if (session > 0)
 572		printk(KERN_ERR "ISOFS: Invalid session number\n");
 573#if 0
 574	printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
 575	if (i==0) {
 576		printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
 577		printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
 578	}
 579#endif
 580	if (i==0)
 581#if WE_OBEY_THE_WRITTEN_STANDARDS
 582		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
 583#endif
 584			vol_desc_start=ms_info.addr.lba;
 585	return vol_desc_start;
 586}
 587
 588/*
 589 * Check if root directory is empty (has less than 3 files).
 590 *
 591 * Used to detect broken CDs where ISO root directory is empty but Joliet root
 592 * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
 593 * (and Joliet used instead) or else no files would be visible.
 594 */
 595static bool rootdir_empty(struct super_block *sb, unsigned long block)
 596{
 597	int offset = 0, files = 0, de_len;
 598	struct iso_directory_record *de;
 599	struct buffer_head *bh;
 600
 601	bh = sb_bread(sb, block);
 602	if (!bh)
 603		return true;
 604	while (files < 3) {
 605		de = (struct iso_directory_record *) (bh->b_data + offset);
 606		de_len = *(unsigned char *) de;
 607		if (de_len == 0)
 608			break;
 609		files++;
 610		offset += de_len;
 611	}
 612	brelse(bh);
 613	return files < 3;
 614}
 615
 616/*
 617 * Initialize the superblock and read the root inode.
 618 *
 619 * Note: a check_disk_change() has been done immediately prior
 620 * to this call, so we don't need to check again.
 621 */
 622static int isofs_fill_super(struct super_block *s, void *data, int silent)
 623{
 624	struct buffer_head *bh = NULL, *pri_bh = NULL;
 625	struct hs_primary_descriptor *h_pri = NULL;
 626	struct iso_primary_descriptor *pri = NULL;
 627	struct iso_supplementary_descriptor *sec = NULL;
 628	struct iso_directory_record *rootp;
 629	struct inode *inode;
 630	struct iso9660_options opt;
 631	struct isofs_sb_info *sbi;
 632	unsigned long first_data_zone;
 633	int joliet_level = 0;
 634	int iso_blknum, block;
 635	int orig_zonesize;
 636	int table, error = -EINVAL;
 637	unsigned int vol_desc_start;
 638
 639	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 640	if (!sbi)
 641		return -ENOMEM;
 642	s->s_fs_info = sbi;
 643
 644	if (!parse_options((char *)data, &opt))
 645		goto out_freesbi;
 646
 647	/*
 648	 * First of all, get the hardware blocksize for this device.
 649	 * If we don't know what it is, or the hardware blocksize is
 650	 * larger than the blocksize the user specified, then use
 651	 * that value.
 652	 */
 653	/*
 654	 * What if bugger tells us to go beyond page size?
 655	 */
 656	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
 657
 658	sbi->s_high_sierra = 0; /* default is iso9660 */
 659	sbi->s_session = opt.session;
 660	sbi->s_sbsector = opt.sbsector;
 661
 662	vol_desc_start = (opt.sbsector != -1) ?
 663		opt.sbsector : isofs_get_last_session(s,opt.session);
 664
 665	for (iso_blknum = vol_desc_start+16;
 666		iso_blknum < vol_desc_start+100; iso_blknum++) {
 667		struct hs_volume_descriptor *hdp;
 668		struct iso_volume_descriptor  *vdp;
 669
 670		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
 671		if (!(bh = sb_bread(s, block)))
 672			goto out_no_read;
 673
 674		vdp = (struct iso_volume_descriptor *)bh->b_data;
 675		hdp = (struct hs_volume_descriptor *)bh->b_data;
 676
 677		/*
 678		 * Due to the overlapping physical location of the descriptors,
 679		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
 680		 * proper identification in this case, we first check for ISO.
 681		 */
 682		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
 683			if (isonum_711(vdp->type) == ISO_VD_END)
 684				break;
 685			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
 686				if (!pri) {
 687					pri = (struct iso_primary_descriptor *)vdp;
 688					/* Save the buffer in case we need it ... */
 689					pri_bh = bh;
 690					bh = NULL;
 691				}
 692			}
 693#ifdef CONFIG_JOLIET
 694			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
 695				sec = (struct iso_supplementary_descriptor *)vdp;
 696				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
 697					if (opt.joliet) {
 698						if (sec->escape[2] == 0x40)
 699							joliet_level = 1;
 700						else if (sec->escape[2] == 0x43)
 701							joliet_level = 2;
 702						else if (sec->escape[2] == 0x45)
 703							joliet_level = 3;
 704
 705						printk(KERN_DEBUG "ISO 9660 Extensions: "
 706							"Microsoft Joliet Level %d\n",
 707							joliet_level);
 708					}
 709					goto root_found;
 710				} else {
 711				/* Unknown supplementary volume descriptor */
 712				sec = NULL;
 713				}
 714			}
 715#endif
 716		} else {
 717			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
 718				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
 719					goto out_freebh;
 720
 721				sbi->s_high_sierra = 1;
 722				opt.rock = 0;
 723				h_pri = (struct hs_primary_descriptor *)vdp;
 724				goto root_found;
 725			}
 726		}
 727
 728		/* Just skip any volume descriptors we don't recognize */
 729
 730		brelse(bh);
 731		bh = NULL;
 732	}
 733	/*
 734	 * If we fall through, either no volume descriptor was found,
 735	 * or else we passed a primary descriptor looking for others.
 736	 */
 737	if (!pri)
 738		goto out_unknown_format;
 739	brelse(bh);
 740	bh = pri_bh;
 741	pri_bh = NULL;
 742
 743root_found:
 744	/* We don't support read-write mounts */
 745	if (!sb_rdonly(s)) {
 746		error = -EACCES;
 747		goto out_freebh;
 748	}
 749
 750	if (joliet_level && (!pri || !opt.rock)) {
 751		/* This is the case of Joliet with the norock mount flag.
 752		 * A disc with both Joliet and Rock Ridge is handled later
 753		 */
 754		pri = (struct iso_primary_descriptor *) sec;
 755	}
 756
 757	if(sbi->s_high_sierra){
 758		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
 759		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
 760		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
 761		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
 762	} else {
 763		if (!pri)
 764			goto out_freebh;
 765		rootp = (struct iso_directory_record *) pri->root_directory_record;
 766		sbi->s_nzones = isonum_733(pri->volume_space_size);
 767		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
 768		sbi->s_max_size = isonum_733(pri->volume_space_size);
 769	}
 770
 771	sbi->s_ninodes = 0; /* No way to figure this out easily */
 772
 773	orig_zonesize = sbi->s_log_zone_size;
 774	/*
 775	 * If the zone size is smaller than the hardware sector size,
 776	 * this is a fatal error.  This would occur if the disc drive
 777	 * had sectors that were 2048 bytes, but the filesystem had
 778	 * blocks that were 512 bytes (which should only very rarely
 779	 * happen.)
 780	 */
 781	if (orig_zonesize < opt.blocksize)
 782		goto out_bad_size;
 783
 784	/* RDE: convert log zone size to bit shift */
 785	switch (sbi->s_log_zone_size) {
 786	case  512: sbi->s_log_zone_size =  9; break;
 787	case 1024: sbi->s_log_zone_size = 10; break;
 788	case 2048: sbi->s_log_zone_size = 11; break;
 789
 790	default:
 791		goto out_bad_zone_size;
 792	}
 793
 794	s->s_magic = ISOFS_SUPER_MAGIC;
 795
 796	/*
 797	 * With multi-extent files, file size is only limited by the maximum
 798	 * size of a file system, which is 8 TB.
 799	 */
 800	s->s_maxbytes = 0x80000000000LL;
 801
 802	/* Set this for reference. Its not currently used except on write
 803	   which we don't have .. */
 804
 805	first_data_zone = isonum_733(rootp->extent) +
 806			  isonum_711(rootp->ext_attr_length);
 807	sbi->s_firstdatazone = first_data_zone;
 808#ifndef BEQUIET
 809	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
 810		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
 811	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
 812	if(sbi->s_high_sierra)
 813		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
 814#endif
 815
 816	/*
 817	 * If the Joliet level is set, we _may_ decide to use the
 818	 * secondary descriptor, but can't be sure until after we
 819	 * read the root inode. But before reading the root inode
 820	 * we may need to change the device blocksize, and would
 821	 * rather release the old buffer first. So, we cache the
 822	 * first_data_zone value from the secondary descriptor.
 823	 */
 824	if (joliet_level) {
 825		pri = (struct iso_primary_descriptor *) sec;
 826		rootp = (struct iso_directory_record *)
 827			pri->root_directory_record;
 828		first_data_zone = isonum_733(rootp->extent) +
 829				isonum_711(rootp->ext_attr_length);
 830	}
 831
 832	/*
 833	 * We're all done using the volume descriptor, and may need
 834	 * to change the device blocksize, so release the buffer now.
 835	 */
 836	brelse(pri_bh);
 837	brelse(bh);
 838
 839	/*
 840	 * Force the blocksize to 512 for 512 byte sectors.  The file
 841	 * read primitives really get it wrong in a bad way if we don't
 842	 * do this.
 843	 *
 844	 * Note - we should never be setting the blocksize to something
 845	 * less than the hardware sector size for the device.  If we
 846	 * do, we would end up having to read larger buffers and split
 847	 * out portions to satisfy requests.
 848	 *
 849	 * Note2- the idea here is that we want to deal with the optimal
 850	 * zonesize in the filesystem.  If we have it set to something less,
 851	 * then we have horrible problems with trying to piece together
 852	 * bits of adjacent blocks in order to properly read directory
 853	 * entries.  By forcing the blocksize in this way, we ensure
 854	 * that we will never be required to do this.
 855	 */
 856	sb_set_blocksize(s, orig_zonesize);
 857
 858	sbi->s_nls_iocharset = NULL;
 859
 860#ifdef CONFIG_JOLIET
 861	if (joliet_level && opt.utf8 == 0) {
 862		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
 863		sbi->s_nls_iocharset = load_nls(p);
 864		if (! sbi->s_nls_iocharset) {
 865			/* Fail only if explicit charset specified */
 866			if (opt.iocharset)
 867				goto out_freesbi;
 868			sbi->s_nls_iocharset = load_nls_default();
 869		}
 870	}
 871#endif
 872	s->s_op = &isofs_sops;
 873	s->s_export_op = &isofs_export_ops;
 874	sbi->s_mapping = opt.map;
 875	sbi->s_rock = (opt.rock ? 2 : 0);
 876	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
 877	sbi->s_cruft = opt.cruft;
 878	sbi->s_hide = opt.hide;
 879	sbi->s_showassoc = opt.showassoc;
 880	sbi->s_uid = opt.uid;
 881	sbi->s_gid = opt.gid;
 882	sbi->s_uid_set = opt.uid_set;
 883	sbi->s_gid_set = opt.gid_set;
 884	sbi->s_utf8 = opt.utf8;
 885	sbi->s_nocompress = opt.nocompress;
 886	sbi->s_overriderockperm = opt.overriderockperm;
 887	/*
 888	 * It would be incredibly stupid to allow people to mark every file
 889	 * on the disk as suid, so we merely allow them to set the default
 890	 * permissions.
 891	 */
 892	if (opt.fmode != ISOFS_INVALID_MODE)
 893		sbi->s_fmode = opt.fmode & 0777;
 894	else
 895		sbi->s_fmode = ISOFS_INVALID_MODE;
 896	if (opt.dmode != ISOFS_INVALID_MODE)
 897		sbi->s_dmode = opt.dmode & 0777;
 898	else
 899		sbi->s_dmode = ISOFS_INVALID_MODE;
 900
 901	/*
 902	 * Read the root inode, which _may_ result in changing
 903	 * the s_rock flag. Once we have the final s_rock value,
 904	 * we then decide whether to use the Joliet descriptor.
 905	 */
 906	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
 907	if (IS_ERR(inode))
 908		goto out_no_root;
 909
 910	/*
 911	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
 912	 * correct Joliet root directory.
 913	 */
 914	if (sbi->s_rock == 1 && joliet_level &&
 915				rootdir_empty(s, sbi->s_firstdatazone)) {
 916		printk(KERN_NOTICE
 917			"ISOFS: primary root directory is empty. "
 918			"Disabling Rock Ridge and switching to Joliet.");
 919		sbi->s_rock = 0;
 920	}
 921
 922	/*
 923	 * If this disk has both Rock Ridge and Joliet on it, then we
 924	 * want to use Rock Ridge by default.  This can be overridden
 925	 * by using the norock mount option.  There is still one other
 926	 * possibility that is not taken into account: a Rock Ridge
 927	 * CD with Unicode names.  Until someone sees such a beast, it
 928	 * will not be supported.
 929	 */
 930	if (sbi->s_rock == 1) {
 931		joliet_level = 0;
 932	} else if (joliet_level) {
 933		sbi->s_rock = 0;
 934		if (sbi->s_firstdatazone != first_data_zone) {
 935			sbi->s_firstdatazone = first_data_zone;
 936			printk(KERN_DEBUG
 937				"ISOFS: changing to secondary root\n");
 938			iput(inode);
 939			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
 940			if (IS_ERR(inode))
 941				goto out_no_root;
 942		}
 943	}
 944
 945	if (opt.check == 'u') {
 946		/* Only Joliet is case insensitive by default */
 947		if (joliet_level)
 948			opt.check = 'r';
 949		else
 950			opt.check = 's';
 951	}
 952	sbi->s_joliet_level = joliet_level;
 953
 954	/* Make sure the root inode is a directory */
 955	if (!S_ISDIR(inode->i_mode)) {
 956		printk(KERN_WARNING
 957			"isofs_fill_super: root inode is not a directory. "
 958			"Corrupted media?\n");
 959		goto out_iput;
 960	}
 961
 962	table = 0;
 963	if (joliet_level)
 964		table += 2;
 965	if (opt.check == 'r')
 966		table++;
 967	sbi->s_check = opt.check;
 968
 969	if (table)
 970		s->s_d_op = &isofs_dentry_ops[table - 1];
 971
 972	/* get the root dentry */
 973	s->s_root = d_make_root(inode);
 974	if (!(s->s_root)) {
 975		error = -ENOMEM;
 976		goto out_no_inode;
 977	}
 978
 979	kfree(opt.iocharset);
 980
 981	return 0;
 982
 983	/*
 984	 * Display error messages and free resources.
 985	 */
 986out_iput:
 987	iput(inode);
 988	goto out_no_inode;
 989out_no_root:
 990	error = PTR_ERR(inode);
 991	if (error != -ENOMEM)
 992		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
 993out_no_inode:
 994#ifdef CONFIG_JOLIET
 995	unload_nls(sbi->s_nls_iocharset);
 996#endif
 997	goto out_freesbi;
 998out_no_read:
 999	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
1000		__func__, s->s_id, iso_blknum, block);
1001	goto out_freebh;
1002out_bad_zone_size:
1003	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1004		sbi->s_log_zone_size);
1005	goto out_freebh;
1006out_bad_size:
1007	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1008		orig_zonesize, opt.blocksize);
1009	goto out_freebh;
1010out_unknown_format:
1011	if (!silent)
1012		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1013
1014out_freebh:
1015	brelse(bh);
1016	brelse(pri_bh);
1017out_freesbi:
1018	kfree(opt.iocharset);
1019	kfree(sbi);
1020	s->s_fs_info = NULL;
1021	return error;
1022}
1023
1024static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1025{
1026	struct super_block *sb = dentry->d_sb;
1027	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1028
1029	buf->f_type = ISOFS_SUPER_MAGIC;
1030	buf->f_bsize = sb->s_blocksize;
1031	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1032		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1033	buf->f_bfree = 0;
1034	buf->f_bavail = 0;
1035	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1036	buf->f_ffree = 0;
1037	buf->f_fsid.val[0] = (u32)id;
1038	buf->f_fsid.val[1] = (u32)(id >> 32);
1039	buf->f_namelen = NAME_MAX;
1040	return 0;
1041}
1042
1043/*
1044 * Get a set of blocks; filling in buffer_heads if already allocated
1045 * or getblk() if they are not.  Returns the number of blocks inserted
1046 * (-ve == error.)
1047 */
1048int isofs_get_blocks(struct inode *inode, sector_t iblock,
1049		     struct buffer_head **bh, unsigned long nblocks)
1050{
1051	unsigned long b_off = iblock;
1052	unsigned offset, sect_size;
1053	unsigned int firstext;
1054	unsigned long nextblk, nextoff;
1055	int section, rv, error;
1056	struct iso_inode_info *ei = ISOFS_I(inode);
1057
1058	error = -EIO;
1059	rv = 0;
1060	if (iblock != b_off) {
1061		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1062		goto abort;
1063	}
1064
1065
1066	offset = 0;
1067	firstext = ei->i_first_extent;
1068	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1069	nextblk = ei->i_next_section_block;
1070	nextoff = ei->i_next_section_offset;
1071	section = 0;
1072
1073	while (nblocks) {
1074		/* If we are *way* beyond the end of the file, print a message.
1075		 * Access beyond the end of the file up to the next page boundary
1076		 * is normal, however because of the way the page cache works.
1077		 * In this case, we just return 0 so that we can properly fill
1078		 * the page with useless information without generating any
1079		 * I/O errors.
1080		 */
1081		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1082			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1083				__func__, b_off,
1084				(unsigned long long)inode->i_size);
1085			goto abort;
1086		}
1087
1088		/* On the last section, nextblk == 0, section size is likely to
1089		 * exceed sect_size by a partial block, and access beyond the
1090		 * end of the file will reach beyond the section size, too.
1091		 */
1092		while (nextblk && (b_off >= (offset + sect_size))) {
1093			struct inode *ninode;
1094
1095			offset += sect_size;
1096			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1097			if (IS_ERR(ninode)) {
1098				error = PTR_ERR(ninode);
1099				goto abort;
1100			}
1101			firstext  = ISOFS_I(ninode)->i_first_extent;
1102			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1103			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1104			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1105			iput(ninode);
1106
1107			if (++section > 100) {
1108				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1109					" aborting...\n", __func__);
1110				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1111					"nextblk=%lu nextoff=%lu\n", __func__,
1112					b_off, firstext, (unsigned) sect_size,
1113					nextblk, nextoff);
1114				goto abort;
1115			}
1116		}
1117
1118		if (*bh) {
1119			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1120		} else {
1121			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1122			if (!*bh)
1123				goto abort;
1124		}
1125		bh++;	/* Next buffer head */
1126		b_off++;	/* Next buffer offset */
1127		nblocks--;
1128		rv++;
1129	}
1130
1131	error = 0;
1132abort:
1133	return rv != 0 ? rv : error;
1134}
1135
1136/*
1137 * Used by the standard interfaces.
1138 */
1139static int isofs_get_block(struct inode *inode, sector_t iblock,
1140		    struct buffer_head *bh_result, int create)
1141{
1142	int ret;
1143
1144	if (create) {
1145		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1146		return -EROFS;
1147	}
1148
1149	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1150	return ret < 0 ? ret : 0;
1151}
1152
1153static int isofs_bmap(struct inode *inode, sector_t block)
1154{
1155	struct buffer_head dummy;
1156	int error;
1157
1158	dummy.b_state = 0;
1159	dummy.b_blocknr = -1000;
1160	error = isofs_get_block(inode, block, &dummy, 0);
1161	if (!error)
1162		return dummy.b_blocknr;
1163	return 0;
1164}
1165
1166struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1167{
1168	sector_t blknr = isofs_bmap(inode, block);
1169	if (!blknr)
1170		return NULL;
1171	return sb_bread(inode->i_sb, blknr);
1172}
1173
1174static int isofs_readpage(struct file *file, struct page *page)
1175{
1176	return mpage_readpage(page, isofs_get_block);
1177}
1178
1179static int isofs_readpages(struct file *file, struct address_space *mapping,
1180			struct list_head *pages, unsigned nr_pages)
1181{
1182	return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
1183}
1184
1185static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1186{
1187	return generic_block_bmap(mapping,block,isofs_get_block);
1188}
1189
1190static const struct address_space_operations isofs_aops = {
1191	.readpage = isofs_readpage,
1192	.readpages = isofs_readpages,
1193	.bmap = _isofs_bmap
1194};
1195
1196static int isofs_read_level3_size(struct inode *inode)
1197{
1198	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1199	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1200	struct buffer_head *bh = NULL;
1201	unsigned long block, offset, block_saved, offset_saved;
1202	int i = 0;
1203	int more_entries = 0;
1204	struct iso_directory_record *tmpde = NULL;
1205	struct iso_inode_info *ei = ISOFS_I(inode);
1206
1207	inode->i_size = 0;
1208
1209	/* The first 16 blocks are reserved as the System Area.  Thus,
1210	 * no inodes can appear in block 0.  We use this to flag that
1211	 * this is the last section. */
1212	ei->i_next_section_block = 0;
1213	ei->i_next_section_offset = 0;
1214
1215	block = ei->i_iget5_block;
1216	offset = ei->i_iget5_offset;
1217
1218	do {
1219		struct iso_directory_record *de;
1220		unsigned int de_len;
1221
1222		if (!bh) {
1223			bh = sb_bread(inode->i_sb, block);
1224			if (!bh)
1225				goto out_noread;
1226		}
1227		de = (struct iso_directory_record *) (bh->b_data + offset);
1228		de_len = *(unsigned char *) de;
1229
1230		if (de_len == 0) {
1231			brelse(bh);
1232			bh = NULL;
1233			++block;
1234			offset = 0;
1235			continue;
1236		}
1237
1238		block_saved = block;
1239		offset_saved = offset;
1240		offset += de_len;
1241
1242		/* Make sure we have a full directory entry */
1243		if (offset >= bufsize) {
1244			int slop = bufsize - offset + de_len;
1245			if (!tmpde) {
1246				tmpde = kmalloc(256, GFP_KERNEL);
1247				if (!tmpde)
1248					goto out_nomem;
1249			}
1250			memcpy(tmpde, de, slop);
1251			offset &= bufsize - 1;
1252			block++;
1253			brelse(bh);
1254			bh = NULL;
1255			if (offset) {
1256				bh = sb_bread(inode->i_sb, block);
1257				if (!bh)
1258					goto out_noread;
1259				memcpy((void *)tmpde+slop, bh->b_data, offset);
1260			}
1261			de = tmpde;
1262		}
1263
1264		inode->i_size += isonum_733(de->size);
1265		if (i == 1) {
1266			ei->i_next_section_block = block_saved;
1267			ei->i_next_section_offset = offset_saved;
1268		}
1269
1270		more_entries = de->flags[-high_sierra] & 0x80;
1271
1272		i++;
1273		if (i > 100)
1274			goto out_toomany;
1275	} while (more_entries);
1276out:
1277	kfree(tmpde);
1278	if (bh)
1279		brelse(bh);
1280	return 0;
1281
1282out_nomem:
1283	if (bh)
1284		brelse(bh);
1285	return -ENOMEM;
1286
1287out_noread:
1288	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1289	kfree(tmpde);
1290	return -EIO;
1291
1292out_toomany:
1293	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1294		"isofs_read_level3_size: inode=%lu\n",
1295		__func__, inode->i_ino);
1296	goto out;
1297}
1298
1299static int isofs_read_inode(struct inode *inode, int relocated)
1300{
1301	struct super_block *sb = inode->i_sb;
1302	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1303	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1304	unsigned long block;
1305	int high_sierra = sbi->s_high_sierra;
1306	struct buffer_head *bh;
1307	struct iso_directory_record *de;
1308	struct iso_directory_record *tmpde = NULL;
1309	unsigned int de_len;
1310	unsigned long offset;
1311	struct iso_inode_info *ei = ISOFS_I(inode);
1312	int ret = -EIO;
1313
1314	block = ei->i_iget5_block;
1315	bh = sb_bread(inode->i_sb, block);
1316	if (!bh)
1317		goto out_badread;
1318
1319	offset = ei->i_iget5_offset;
1320
1321	de = (struct iso_directory_record *) (bh->b_data + offset);
1322	de_len = *(unsigned char *) de;
1323
1324	if (offset + de_len > bufsize) {
1325		int frag1 = bufsize - offset;
1326
1327		tmpde = kmalloc(de_len, GFP_KERNEL);
1328		if (!tmpde) {
1329			ret = -ENOMEM;
1330			goto fail;
1331		}
1332		memcpy(tmpde, bh->b_data + offset, frag1);
1333		brelse(bh);
1334		bh = sb_bread(inode->i_sb, ++block);
1335		if (!bh)
1336			goto out_badread;
1337		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1338		de = tmpde;
1339	}
1340
1341	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1342					ei->i_iget5_offset,
1343					ISOFS_BUFFER_BITS(inode));
1344
1345	/* Assume it is a normal-format file unless told otherwise */
1346	ei->i_file_format = isofs_file_normal;
1347
1348	if (de->flags[-high_sierra] & 2) {
1349		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1350			inode->i_mode = S_IFDIR | sbi->s_dmode;
1351		else
1352			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1353		set_nlink(inode, 1);	/*
1354					 * Set to 1.  We know there are 2, but
1355					 * the find utility tries to optimize
1356					 * if it is 2, and it screws up.  It is
1357					 * easier to give 1 which tells find to
1358					 * do it the hard way.
1359					 */
1360	} else {
1361		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1362			inode->i_mode = S_IFREG | sbi->s_fmode;
1363		} else {
1364			/*
1365			 * Set default permissions: r-x for all.  The disc
1366			 * could be shared with DOS machines so virtually
1367			 * anything could be a valid executable.
1368			 */
1369			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1370		}
1371		set_nlink(inode, 1);
1372	}
1373	inode->i_uid = sbi->s_uid;
1374	inode->i_gid = sbi->s_gid;
1375	inode->i_blocks = 0;
1376
1377	ei->i_format_parm[0] = 0;
1378	ei->i_format_parm[1] = 0;
1379	ei->i_format_parm[2] = 0;
1380
1381	ei->i_section_size = isonum_733(de->size);
1382	if (de->flags[-high_sierra] & 0x80) {
1383		ret = isofs_read_level3_size(inode);
1384		if (ret < 0)
1385			goto fail;
1386		ret = -EIO;
1387	} else {
1388		ei->i_next_section_block = 0;
1389		ei->i_next_section_offset = 0;
1390		inode->i_size = isonum_733(de->size);
1391	}
1392
1393	/*
1394	 * Some dipshit decided to store some other bit of information
1395	 * in the high byte of the file length.  Truncate size in case
1396	 * this CDROM was mounted with the cruft option.
1397	 */
1398
1399	if (sbi->s_cruft)
1400		inode->i_size &= 0x00ffffff;
1401
1402	if (de->interleave[0]) {
1403		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1404		inode->i_size = 0;
1405	}
1406
1407	/* I have no idea what file_unit_size is used for, so
1408	   we will flag it for now */
1409	if (de->file_unit_size[0] != 0) {
1410		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1411			inode->i_ino);
1412	}
1413
1414	/* I have no idea what other flag bits are used for, so
1415	   we will flag it for now */
1416#ifdef DEBUG
1417	if((de->flags[-high_sierra] & ~2)!= 0){
1418		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1419				"(%ld %x).\n",
1420			inode->i_ino, de->flags[-high_sierra]);
1421	}
1422#endif
1423
1424	inode->i_mtime.tv_sec =
1425	inode->i_atime.tv_sec =
1426	inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1427	inode->i_mtime.tv_nsec =
1428	inode->i_atime.tv_nsec =
1429	inode->i_ctime.tv_nsec = 0;
1430
1431	ei->i_first_extent = (isonum_733(de->extent) +
1432			isonum_711(de->ext_attr_length));
1433
1434	/* Set the number of blocks for stat() - should be done before RR */
1435	inode->i_blocks = (inode->i_size + 511) >> 9;
1436
1437	/*
1438	 * Now test for possible Rock Ridge extensions which will override
1439	 * some of these numbers in the inode structure.
1440	 */
1441
1442	if (!high_sierra) {
1443		parse_rock_ridge_inode(de, inode, relocated);
1444		/* if we want uid/gid set, override the rock ridge setting */
1445		if (sbi->s_uid_set)
1446			inode->i_uid = sbi->s_uid;
1447		if (sbi->s_gid_set)
1448			inode->i_gid = sbi->s_gid;
1449	}
1450	/* Now set final access rights if overriding rock ridge setting */
1451	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1452	    sbi->s_dmode != ISOFS_INVALID_MODE)
1453		inode->i_mode = S_IFDIR | sbi->s_dmode;
1454	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1455	    sbi->s_fmode != ISOFS_INVALID_MODE)
1456		inode->i_mode = S_IFREG | sbi->s_fmode;
1457
1458	/* Install the inode operations vector */
1459	if (S_ISREG(inode->i_mode)) {
1460		inode->i_fop = &generic_ro_fops;
1461		switch (ei->i_file_format) {
1462#ifdef CONFIG_ZISOFS
1463		case isofs_file_compressed:
1464			inode->i_data.a_ops = &zisofs_aops;
1465			break;
1466#endif
1467		default:
1468			inode->i_data.a_ops = &isofs_aops;
1469			break;
1470		}
1471	} else if (S_ISDIR(inode->i_mode)) {
1472		inode->i_op = &isofs_dir_inode_operations;
1473		inode->i_fop = &isofs_dir_operations;
1474	} else if (S_ISLNK(inode->i_mode)) {
1475		inode->i_op = &page_symlink_inode_operations;
1476		inode_nohighmem(inode);
1477		inode->i_data.a_ops = &isofs_symlink_aops;
1478	} else
1479		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1480		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1481
1482	ret = 0;
1483out:
1484	kfree(tmpde);
1485	if (bh)
1486		brelse(bh);
1487	return ret;
1488
1489out_badread:
1490	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1491fail:
1492	goto out;
1493}
1494
1495struct isofs_iget5_callback_data {
1496	unsigned long block;
1497	unsigned long offset;
1498};
1499
1500static int isofs_iget5_test(struct inode *ino, void *data)
1501{
1502	struct iso_inode_info *i = ISOFS_I(ino);
1503	struct isofs_iget5_callback_data *d =
1504		(struct isofs_iget5_callback_data*)data;
1505	return (i->i_iget5_block == d->block)
1506		&& (i->i_iget5_offset == d->offset);
1507}
1508
1509static int isofs_iget5_set(struct inode *ino, void *data)
1510{
1511	struct iso_inode_info *i = ISOFS_I(ino);
1512	struct isofs_iget5_callback_data *d =
1513		(struct isofs_iget5_callback_data*)data;
1514	i->i_iget5_block = d->block;
1515	i->i_iget5_offset = d->offset;
1516	return 0;
1517}
1518
1519/* Store, in the inode's containing structure, the block and block
1520 * offset that point to the underlying meta-data for the inode.  The
1521 * code below is otherwise similar to the iget() code in
1522 * include/linux/fs.h */
1523struct inode *__isofs_iget(struct super_block *sb,
1524			   unsigned long block,
1525			   unsigned long offset,
1526			   int relocated)
1527{
1528	unsigned long hashval;
1529	struct inode *inode;
1530	struct isofs_iget5_callback_data data;
1531	long ret;
1532
1533	if (offset >= 1ul << sb->s_blocksize_bits)
1534		return ERR_PTR(-EINVAL);
1535
1536	data.block = block;
1537	data.offset = offset;
1538
1539	hashval = (block << sb->s_blocksize_bits) | offset;
1540
1541	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1542				&isofs_iget5_set, &data);
1543
1544	if (!inode)
1545		return ERR_PTR(-ENOMEM);
1546
1547	if (inode->i_state & I_NEW) {
1548		ret = isofs_read_inode(inode, relocated);
1549		if (ret < 0) {
1550			iget_failed(inode);
1551			inode = ERR_PTR(ret);
1552		} else {
1553			unlock_new_inode(inode);
1554		}
1555	}
1556
1557	return inode;
1558}
1559
1560static struct dentry *isofs_mount(struct file_system_type *fs_type,
1561	int flags, const char *dev_name, void *data)
1562{
1563	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1564}
1565
1566static struct file_system_type iso9660_fs_type = {
1567	.owner		= THIS_MODULE,
1568	.name		= "iso9660",
1569	.mount		= isofs_mount,
1570	.kill_sb	= kill_block_super,
1571	.fs_flags	= FS_REQUIRES_DEV,
1572};
1573MODULE_ALIAS_FS("iso9660");
1574MODULE_ALIAS("iso9660");
1575
1576static int __init init_iso9660_fs(void)
1577{
1578	int err = init_inodecache();
1579	if (err)
1580		goto out;
1581#ifdef CONFIG_ZISOFS
1582	err = zisofs_init();
1583	if (err)
1584		goto out1;
1585#endif
1586	err = register_filesystem(&iso9660_fs_type);
1587	if (err)
1588		goto out2;
1589	return 0;
1590out2:
1591#ifdef CONFIG_ZISOFS
1592	zisofs_cleanup();
1593out1:
1594#endif
1595	destroy_inodecache();
1596out:
1597	return err;
1598}
1599
1600static void __exit exit_iso9660_fs(void)
1601{
1602        unregister_filesystem(&iso9660_fs_type);
1603#ifdef CONFIG_ZISOFS
1604	zisofs_cleanup();
1605#endif
1606	destroy_inodecache();
1607}
1608
1609module_init(init_iso9660_fs)
1610module_exit(exit_iso9660_fs)
1611MODULE_LICENSE("GPL");
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  linux/fs/isofs/inode.c
   4 *
   5 *  (C) 1991  Linus Torvalds - minix filesystem
   6 *      1992, 1993, 1994  Eric Youngdale Modified for ISO 9660 filesystem.
   7 *      1994  Eberhard Mönkeberg - multi session handling.
   8 *      1995  Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
   9 *	1997  Gordon Chaffee - Joliet CDs
  10 *	1998  Eric Lammerts - ISO 9660 Level 3
  11 *	2004  Paul Serice - Inode Support pushed out from 4GB to 128GB
  12 *	2004  Paul Serice - NFS Export Operations
  13 */
  14
  15#include <linux/init.h>
  16#include <linux/module.h>
  17
  18#include <linux/slab.h>
  19#include <linux/cred.h>
  20#include <linux/nls.h>
  21#include <linux/ctype.h>
  22#include <linux/statfs.h>
  23#include <linux/cdrom.h>
  24#include <linux/parser.h>
  25#include <linux/mpage.h>
  26#include <linux/user_namespace.h>
  27#include <linux/seq_file.h>
  28#include <linux/blkdev.h>
  29
  30#include "isofs.h"
  31#include "zisofs.h"
  32
  33/* max tz offset is 13 hours */
  34#define MAX_TZ_OFFSET (52*15*60)
  35
  36#define BEQUIET
  37
  38static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
  39static int isofs_dentry_cmpi(const struct dentry *dentry,
  40		unsigned int len, const char *str, const struct qstr *name);
  41
  42#ifdef CONFIG_JOLIET
  43static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
  44static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
  45static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
  46		unsigned int len, const char *str, const struct qstr *name);
  47static int isofs_dentry_cmp_ms(const struct dentry *dentry,
  48		unsigned int len, const char *str, const struct qstr *name);
  49#endif
  50
  51static void isofs_put_super(struct super_block *sb)
  52{
  53	struct isofs_sb_info *sbi = ISOFS_SB(sb);
  54
  55#ifdef CONFIG_JOLIET
  56	unload_nls(sbi->s_nls_iocharset);
  57#endif
  58
  59	kfree(sbi);
  60	sb->s_fs_info = NULL;
  61	return;
  62}
  63
  64static int isofs_read_inode(struct inode *, int relocated);
  65static int isofs_statfs (struct dentry *, struct kstatfs *);
  66static int isofs_show_options(struct seq_file *, struct dentry *);
  67
  68static struct kmem_cache *isofs_inode_cachep;
  69
  70static struct inode *isofs_alloc_inode(struct super_block *sb)
  71{
  72	struct iso_inode_info *ei;
  73	ei = alloc_inode_sb(sb, isofs_inode_cachep, GFP_KERNEL);
  74	if (!ei)
  75		return NULL;
  76	return &ei->vfs_inode;
  77}
  78
  79static void isofs_free_inode(struct inode *inode)
  80{
  81	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
  82}
  83
  84static void init_once(void *foo)
  85{
  86	struct iso_inode_info *ei = foo;
  87
  88	inode_init_once(&ei->vfs_inode);
  89}
  90
  91static int __init init_inodecache(void)
  92{
  93	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
  94					sizeof(struct iso_inode_info),
  95					0, (SLAB_RECLAIM_ACCOUNT|
  96					SLAB_ACCOUNT),
  97					init_once);
  98	if (!isofs_inode_cachep)
  99		return -ENOMEM;
 100	return 0;
 101}
 102
 103static void destroy_inodecache(void)
 104{
 105	/*
 106	 * Make sure all delayed rcu free inodes are flushed before we
 107	 * destroy cache.
 108	 */
 109	rcu_barrier();
 110	kmem_cache_destroy(isofs_inode_cachep);
 111}
 112
 113static int isofs_remount(struct super_block *sb, int *flags, char *data)
 114{
 115	sync_filesystem(sb);
 116	if (!(*flags & SB_RDONLY))
 117		return -EROFS;
 118	return 0;
 119}
 120
 121static const struct super_operations isofs_sops = {
 122	.alloc_inode	= isofs_alloc_inode,
 123	.free_inode	= isofs_free_inode,
 124	.put_super	= isofs_put_super,
 125	.statfs		= isofs_statfs,
 126	.remount_fs	= isofs_remount,
 127	.show_options	= isofs_show_options,
 128};
 129
 130
 131static const struct dentry_operations isofs_dentry_ops[] = {
 132	{
 133		.d_hash		= isofs_hashi,
 134		.d_compare	= isofs_dentry_cmpi,
 135	},
 136#ifdef CONFIG_JOLIET
 137	{
 138		.d_hash		= isofs_hash_ms,
 139		.d_compare	= isofs_dentry_cmp_ms,
 140	},
 141	{
 142		.d_hash		= isofs_hashi_ms,
 143		.d_compare	= isofs_dentry_cmpi_ms,
 144	},
 145#endif
 146};
 147
 148struct iso9660_options{
 149	unsigned int rock:1;
 150	unsigned int joliet:1;
 151	unsigned int cruft:1;
 152	unsigned int hide:1;
 153	unsigned int showassoc:1;
 154	unsigned int nocompress:1;
 155	unsigned int overriderockperm:1;
 156	unsigned int uid_set:1;
 157	unsigned int gid_set:1;
 158	unsigned char map;
 159	unsigned char check;
 160	unsigned int blocksize;
 161	umode_t fmode;
 162	umode_t dmode;
 163	kgid_t gid;
 164	kuid_t uid;
 165	char *iocharset;
 166	/* LVE */
 167	s32 session;
 168	s32 sbsector;
 169};
 170
 171/*
 172 * Compute the hash for the isofs name corresponding to the dentry.
 173 */
 174static int
 175isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
 176{
 177	const char *name;
 178	int len;
 179	char c;
 180	unsigned long hash;
 181
 182	len = qstr->len;
 183	name = qstr->name;
 184	if (ms) {
 185		while (len && name[len-1] == '.')
 186			len--;
 187	}
 188
 189	hash = init_name_hash(dentry);
 190	while (len--) {
 191		c = tolower(*name++);
 192		hash = partial_name_hash(c, hash);
 193	}
 194	qstr->hash = end_name_hash(hash);
 195
 196	return 0;
 197}
 198
 199/*
 200 * Compare of two isofs names.
 201 */
 202static int isofs_dentry_cmp_common(
 203		unsigned int len, const char *str,
 204		const struct qstr *name, int ms, int ci)
 205{
 206	int alen, blen;
 207
 208	/* A filename cannot end in '.' or we treat it like it has none */
 209	alen = name->len;
 210	blen = len;
 211	if (ms) {
 212		while (alen && name->name[alen-1] == '.')
 213			alen--;
 214		while (blen && str[blen-1] == '.')
 215			blen--;
 216	}
 217	if (alen == blen) {
 218		if (ci) {
 219			if (strncasecmp(name->name, str, alen) == 0)
 220				return 0;
 221		} else {
 222			if (strncmp(name->name, str, alen) == 0)
 223				return 0;
 224		}
 225	}
 226	return 1;
 227}
 228
 229static int
 230isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
 231{
 232	return isofs_hashi_common(dentry, qstr, 0);
 233}
 234
 235static int
 236isofs_dentry_cmpi(const struct dentry *dentry,
 237		unsigned int len, const char *str, const struct qstr *name)
 238{
 239	return isofs_dentry_cmp_common(len, str, name, 0, 1);
 240}
 241
 242#ifdef CONFIG_JOLIET
 243/*
 244 * Compute the hash for the isofs name corresponding to the dentry.
 245 */
 246static int
 247isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
 248{
 249	const char *name;
 250	int len;
 251
 252	len = qstr->len;
 253	name = qstr->name;
 254	if (ms) {
 255		while (len && name[len-1] == '.')
 256			len--;
 257	}
 258
 259	qstr->hash = full_name_hash(dentry, name, len);
 260
 261	return 0;
 262}
 263
 264static int
 265isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
 266{
 267	return isofs_hash_common(dentry, qstr, 1);
 268}
 269
 270static int
 271isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
 272{
 273	return isofs_hashi_common(dentry, qstr, 1);
 274}
 275
 276static int
 277isofs_dentry_cmp_ms(const struct dentry *dentry,
 278		unsigned int len, const char *str, const struct qstr *name)
 279{
 280	return isofs_dentry_cmp_common(len, str, name, 1, 0);
 281}
 282
 283static int
 284isofs_dentry_cmpi_ms(const struct dentry *dentry,
 285		unsigned int len, const char *str, const struct qstr *name)
 286{
 287	return isofs_dentry_cmp_common(len, str, name, 1, 1);
 288}
 289#endif
 290
 291enum {
 292	Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
 293	Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
 294	Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
 295	Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
 296};
 297
 298static const match_table_t tokens = {
 299	{Opt_norock, "norock"},
 300	{Opt_nojoliet, "nojoliet"},
 301	{Opt_unhide, "unhide"},
 302	{Opt_hide, "hide"},
 303	{Opt_showassoc, "showassoc"},
 304	{Opt_cruft, "cruft"},
 305	{Opt_utf8, "utf8"},
 306	{Opt_iocharset, "iocharset=%s"},
 307	{Opt_map_a, "map=acorn"},
 308	{Opt_map_a, "map=a"},
 309	{Opt_map_n, "map=normal"},
 310	{Opt_map_n, "map=n"},
 311	{Opt_map_o, "map=off"},
 312	{Opt_map_o, "map=o"},
 313	{Opt_session, "session=%u"},
 314	{Opt_sb, "sbsector=%u"},
 315	{Opt_check_r, "check=relaxed"},
 316	{Opt_check_r, "check=r"},
 317	{Opt_check_s, "check=strict"},
 318	{Opt_check_s, "check=s"},
 319	{Opt_uid, "uid=%u"},
 320	{Opt_gid, "gid=%u"},
 321	{Opt_mode, "mode=%u"},
 322	{Opt_dmode, "dmode=%u"},
 323	{Opt_overriderockperm, "overriderockperm"},
 324	{Opt_block, "block=%u"},
 325	{Opt_ignore, "conv=binary"},
 326	{Opt_ignore, "conv=b"},
 327	{Opt_ignore, "conv=text"},
 328	{Opt_ignore, "conv=t"},
 329	{Opt_ignore, "conv=mtext"},
 330	{Opt_ignore, "conv=m"},
 331	{Opt_ignore, "conv=auto"},
 332	{Opt_ignore, "conv=a"},
 333	{Opt_nocompress, "nocompress"},
 334	{Opt_err, NULL}
 335};
 336
 337static int parse_options(char *options, struct iso9660_options *popt)
 338{
 339	char *p;
 340	int option;
 341	unsigned int uv;
 342
 343	popt->map = 'n';
 344	popt->rock = 1;
 345	popt->joliet = 1;
 346	popt->cruft = 0;
 347	popt->hide = 0;
 348	popt->showassoc = 0;
 349	popt->check = 'u';		/* unset */
 350	popt->nocompress = 0;
 351	popt->blocksize = 1024;
 352	popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
 353	popt->uid_set = 0;
 354	popt->gid_set = 0;
 355	popt->gid = GLOBAL_ROOT_GID;
 356	popt->uid = GLOBAL_ROOT_UID;
 357	popt->iocharset = NULL;
 358	popt->overriderockperm = 0;
 359	popt->session=-1;
 360	popt->sbsector=-1;
 361	if (!options)
 362		return 1;
 363
 364	while ((p = strsep(&options, ",")) != NULL) {
 365		int token;
 366		substring_t args[MAX_OPT_ARGS];
 367		unsigned n;
 368
 369		if (!*p)
 370			continue;
 371
 372		token = match_token(p, tokens, args);
 373		switch (token) {
 374		case Opt_norock:
 375			popt->rock = 0;
 376			break;
 377		case Opt_nojoliet:
 378			popt->joliet = 0;
 379			break;
 380		case Opt_hide:
 381			popt->hide = 1;
 382			break;
 383		case Opt_unhide:
 384		case Opt_showassoc:
 385			popt->showassoc = 1;
 386			break;
 387		case Opt_cruft:
 388			popt->cruft = 1;
 389			break;
 390#ifdef CONFIG_JOLIET
 391		case Opt_utf8:
 392			kfree(popt->iocharset);
 393			popt->iocharset = kstrdup("utf8", GFP_KERNEL);
 394			if (!popt->iocharset)
 395				return 0;
 396			break;
 397		case Opt_iocharset:
 398			kfree(popt->iocharset);
 399			popt->iocharset = match_strdup(&args[0]);
 400			if (!popt->iocharset)
 401				return 0;
 402			break;
 403#endif
 404		case Opt_map_a:
 405			popt->map = 'a';
 406			break;
 407		case Opt_map_o:
 408			popt->map = 'o';
 409			break;
 410		case Opt_map_n:
 411			popt->map = 'n';
 412			break;
 413		case Opt_session:
 414			if (match_int(&args[0], &option))
 415				return 0;
 416			n = option;
 417			/*
 418			 * Track numbers are supposed to be in range 1-99, the
 419			 * mount option starts indexing at 0.
 420			 */
 421			if (n >= 99)
 422				return 0;
 423			popt->session = n + 1;
 424			break;
 425		case Opt_sb:
 426			if (match_int(&args[0], &option))
 427				return 0;
 428			popt->sbsector = option;
 429			break;
 430		case Opt_check_r:
 431			popt->check = 'r';
 432			break;
 433		case Opt_check_s:
 434			popt->check = 's';
 435			break;
 436		case Opt_ignore:
 437			break;
 438		case Opt_uid:
 439			if (match_uint(&args[0], &uv))
 440				return 0;
 441			popt->uid = make_kuid(current_user_ns(), uv);
 442			if (!uid_valid(popt->uid))
 443				return 0;
 444			popt->uid_set = 1;
 445			break;
 446		case Opt_gid:
 447			if (match_uint(&args[0], &uv))
 448				return 0;
 449			popt->gid = make_kgid(current_user_ns(), uv);
 450			if (!gid_valid(popt->gid))
 451				return 0;
 452			popt->gid_set = 1;
 453			break;
 454		case Opt_mode:
 455			if (match_int(&args[0], &option))
 456				return 0;
 457			popt->fmode = option;
 458			break;
 459		case Opt_dmode:
 460			if (match_int(&args[0], &option))
 461				return 0;
 462			popt->dmode = option;
 463			break;
 464		case Opt_overriderockperm:
 465			popt->overriderockperm = 1;
 466			break;
 467		case Opt_block:
 468			if (match_int(&args[0], &option))
 469				return 0;
 470			n = option;
 471			if (n != 512 && n != 1024 && n != 2048)
 472				return 0;
 473			popt->blocksize = n;
 474			break;
 475		case Opt_nocompress:
 476			popt->nocompress = 1;
 477			break;
 478		default:
 479			return 0;
 480		}
 481	}
 482	return 1;
 483}
 484
 485/*
 486 * Display the mount options in /proc/mounts.
 487 */
 488static int isofs_show_options(struct seq_file *m, struct dentry *root)
 489{
 490	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
 491
 492	if (!sbi->s_rock)		seq_puts(m, ",norock");
 493	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
 494	if (sbi->s_cruft)		seq_puts(m, ",cruft");
 495	if (sbi->s_hide)		seq_puts(m, ",hide");
 496	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
 497	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
 498	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
 499
 500	if (sbi->s_check)		seq_printf(m, ",check=%c", sbi->s_check);
 501	if (sbi->s_mapping)		seq_printf(m, ",map=%c", sbi->s_mapping);
 502	if (sbi->s_session != 255)	seq_printf(m, ",session=%u", sbi->s_session - 1);
 503	if (sbi->s_sbsector != -1)	seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
 504
 505	if (root->d_sb->s_blocksize != 1024)
 506		seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
 507
 508	if (sbi->s_uid_set)
 509		seq_printf(m, ",uid=%u",
 510			   from_kuid_munged(&init_user_ns, sbi->s_uid));
 511	if (sbi->s_gid_set)
 512		seq_printf(m, ",gid=%u",
 513			   from_kgid_munged(&init_user_ns, sbi->s_gid));
 514
 515	if (sbi->s_dmode != ISOFS_INVALID_MODE)
 516		seq_printf(m, ",dmode=%o", sbi->s_dmode);
 517	if (sbi->s_fmode != ISOFS_INVALID_MODE)
 518		seq_printf(m, ",fmode=%o", sbi->s_fmode);
 519
 520#ifdef CONFIG_JOLIET
 521	if (sbi->s_nls_iocharset)
 522		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
 523	else
 524		seq_puts(m, ",iocharset=utf8");
 525#endif
 526	return 0;
 527}
 528
 529/*
 530 * look if the driver can tell the multi session redirection value
 531 *
 532 * don't change this if you don't know what you do, please!
 533 * Multisession is legal only with XA disks.
 534 * A non-XA disk with more than one volume descriptor may do it right, but
 535 * usually is written in a nowhere standardized "multi-partition" manner.
 536 * Multisession uses absolute addressing (solely the first frame of the whole
 537 * track is #0), multi-partition uses relative addressing (each first frame of
 538 * each track is #0), and a track is not a session.
 539 *
 540 * A broken CDwriter software or drive firmware does not set new standards,
 541 * at least not if conflicting with the existing ones.
 542 *
 543 * emoenke@gwdg.de
 544 */
 545#define WE_OBEY_THE_WRITTEN_STANDARDS 1
 546
 547static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
 548{
 549	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);
 550	unsigned int vol_desc_start = 0;
 551
 552	if (session > 0) {
 553		struct cdrom_tocentry te;
 554
 555		if (!cdi)
 556			return 0;
 557
 558		te.cdte_track = session;
 559		te.cdte_format = CDROM_LBA;
 560		if (cdrom_read_tocentry(cdi, &te) == 0) {
 561			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
 562				session, te.cdte_addr.lba,
 563				te.cdte_ctrl & CDROM_DATA_TRACK);
 564			if ((te.cdte_ctrl & CDROM_DATA_TRACK) == 4)
 565				return te.cdte_addr.lba;
 566		}
 567
 568		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
 569	}
 570
 571	if (cdi) {
 572		struct cdrom_multisession ms_info;
 573
 574		ms_info.addr_format = CDROM_LBA;
 575		if (cdrom_multisession(cdi, &ms_info) == 0) {
 576#if WE_OBEY_THE_WRITTEN_STANDARDS
 577			/* necessary for a valid ms_info.addr */
 578			if (ms_info.xa_flag)
 579#endif
 580				vol_desc_start = ms_info.addr.lba;
 581		}
 582	}
 583
 584	return vol_desc_start;
 585}
 586
 587/*
 588 * Check if root directory is empty (has less than 3 files).
 589 *
 590 * Used to detect broken CDs where ISO root directory is empty but Joliet root
 591 * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
 592 * (and Joliet used instead) or else no files would be visible.
 593 */
 594static bool rootdir_empty(struct super_block *sb, unsigned long block)
 595{
 596	int offset = 0, files = 0, de_len;
 597	struct iso_directory_record *de;
 598	struct buffer_head *bh;
 599
 600	bh = sb_bread(sb, block);
 601	if (!bh)
 602		return true;
 603	while (files < 3) {
 604		de = (struct iso_directory_record *) (bh->b_data + offset);
 605		de_len = *(unsigned char *) de;
 606		if (de_len == 0)
 607			break;
 608		files++;
 609		offset += de_len;
 610	}
 611	brelse(bh);
 612	return files < 3;
 613}
 614
 615/*
 616 * Initialize the superblock and read the root inode.
 617 */
 618static int isofs_fill_super(struct super_block *s, void *data, int silent)
 619{
 620	struct buffer_head *bh = NULL, *pri_bh = NULL;
 621	struct hs_primary_descriptor *h_pri = NULL;
 622	struct iso_primary_descriptor *pri = NULL;
 623	struct iso_supplementary_descriptor *sec = NULL;
 624	struct iso_directory_record *rootp;
 625	struct inode *inode;
 626	struct iso9660_options opt;
 627	struct isofs_sb_info *sbi;
 628	unsigned long first_data_zone;
 629	int joliet_level = 0;
 630	int iso_blknum, block;
 631	int orig_zonesize;
 632	int table, error = -EINVAL;
 633	unsigned int vol_desc_start;
 634
 635	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 636	if (!sbi)
 637		return -ENOMEM;
 638	s->s_fs_info = sbi;
 639
 640	if (!parse_options((char *)data, &opt))
 641		goto out_freesbi;
 642
 643	/*
 644	 * First of all, get the hardware blocksize for this device.
 645	 * If we don't know what it is, or the hardware blocksize is
 646	 * larger than the blocksize the user specified, then use
 647	 * that value.
 648	 */
 649	/*
 650	 * What if bugger tells us to go beyond page size?
 651	 */
 652	if (bdev_logical_block_size(s->s_bdev) > 2048) {
 653		printk(KERN_WARNING
 654		       "ISOFS: unsupported/invalid hardware sector size %d\n",
 655			bdev_logical_block_size(s->s_bdev));
 656		goto out_freesbi;
 657	}
 658	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
 659
 660	sbi->s_high_sierra = 0; /* default is iso9660 */
 661	sbi->s_session = opt.session;
 662	sbi->s_sbsector = opt.sbsector;
 663
 664	vol_desc_start = (opt.sbsector != -1) ?
 665		opt.sbsector : isofs_get_last_session(s,opt.session);
 666
 667	for (iso_blknum = vol_desc_start+16;
 668		iso_blknum < vol_desc_start+100; iso_blknum++) {
 669		struct hs_volume_descriptor *hdp;
 670		struct iso_volume_descriptor  *vdp;
 671
 672		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
 673		if (!(bh = sb_bread(s, block)))
 674			goto out_no_read;
 675
 676		vdp = (struct iso_volume_descriptor *)bh->b_data;
 677		hdp = (struct hs_volume_descriptor *)bh->b_data;
 678
 679		/*
 680		 * Due to the overlapping physical location of the descriptors,
 681		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
 682		 * proper identification in this case, we first check for ISO.
 683		 */
 684		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
 685			if (isonum_711(vdp->type) == ISO_VD_END)
 686				break;
 687			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
 688				if (!pri) {
 689					pri = (struct iso_primary_descriptor *)vdp;
 690					/* Save the buffer in case we need it ... */
 691					pri_bh = bh;
 692					bh = NULL;
 693				}
 694			}
 695#ifdef CONFIG_JOLIET
 696			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
 697				sec = (struct iso_supplementary_descriptor *)vdp;
 698				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
 699					if (opt.joliet) {
 700						if (sec->escape[2] == 0x40)
 701							joliet_level = 1;
 702						else if (sec->escape[2] == 0x43)
 703							joliet_level = 2;
 704						else if (sec->escape[2] == 0x45)
 705							joliet_level = 3;
 706
 707						printk(KERN_DEBUG "ISO 9660 Extensions: "
 708							"Microsoft Joliet Level %d\n",
 709							joliet_level);
 710					}
 711					goto root_found;
 712				} else {
 713				/* Unknown supplementary volume descriptor */
 714				sec = NULL;
 715				}
 716			}
 717#endif
 718		} else {
 719			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
 720				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
 721					goto out_freebh;
 722
 723				sbi->s_high_sierra = 1;
 724				opt.rock = 0;
 725				h_pri = (struct hs_primary_descriptor *)vdp;
 726				goto root_found;
 727			}
 728		}
 729
 730		/* Just skip any volume descriptors we don't recognize */
 731
 732		brelse(bh);
 733		bh = NULL;
 734	}
 735	/*
 736	 * If we fall through, either no volume descriptor was found,
 737	 * or else we passed a primary descriptor looking for others.
 738	 */
 739	if (!pri)
 740		goto out_unknown_format;
 741	brelse(bh);
 742	bh = pri_bh;
 743	pri_bh = NULL;
 744
 745root_found:
 746	/* We don't support read-write mounts */
 747	if (!sb_rdonly(s)) {
 748		error = -EACCES;
 749		goto out_freebh;
 750	}
 751
 752	if (joliet_level && (!pri || !opt.rock)) {
 753		/* This is the case of Joliet with the norock mount flag.
 754		 * A disc with both Joliet and Rock Ridge is handled later
 755		 */
 756		pri = (struct iso_primary_descriptor *) sec;
 757	}
 758
 759	if(sbi->s_high_sierra){
 760		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
 761		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
 762		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
 763		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
 764	} else {
 765		if (!pri)
 766			goto out_freebh;
 767		rootp = (struct iso_directory_record *) pri->root_directory_record;
 768		sbi->s_nzones = isonum_733(pri->volume_space_size);
 769		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
 770		sbi->s_max_size = isonum_733(pri->volume_space_size);
 771	}
 772
 773	sbi->s_ninodes = 0; /* No way to figure this out easily */
 774
 775	orig_zonesize = sbi->s_log_zone_size;
 776	/*
 777	 * If the zone size is smaller than the hardware sector size,
 778	 * this is a fatal error.  This would occur if the disc drive
 779	 * had sectors that were 2048 bytes, but the filesystem had
 780	 * blocks that were 512 bytes (which should only very rarely
 781	 * happen.)
 782	 */
 783	if (orig_zonesize < opt.blocksize)
 784		goto out_bad_size;
 785
 786	/* RDE: convert log zone size to bit shift */
 787	switch (sbi->s_log_zone_size) {
 788	case  512: sbi->s_log_zone_size =  9; break;
 789	case 1024: sbi->s_log_zone_size = 10; break;
 790	case 2048: sbi->s_log_zone_size = 11; break;
 791
 792	default:
 793		goto out_bad_zone_size;
 794	}
 795
 796	s->s_magic = ISOFS_SUPER_MAGIC;
 797
 798	/*
 799	 * With multi-extent files, file size is only limited by the maximum
 800	 * size of a file system, which is 8 TB.
 801	 */
 802	s->s_maxbytes = 0x80000000000LL;
 803
 804	/* ECMA-119 timestamp from 1900/1/1 with tz offset */
 805	s->s_time_min = mktime64(1900, 1, 1, 0, 0, 0) - MAX_TZ_OFFSET;
 806	s->s_time_max = mktime64(U8_MAX+1900, 12, 31, 23, 59, 59) + MAX_TZ_OFFSET;
 807
 808	/* Set this for reference. Its not currently used except on write
 809	   which we don't have .. */
 810
 811	first_data_zone = isonum_733(rootp->extent) +
 812			  isonum_711(rootp->ext_attr_length);
 813	sbi->s_firstdatazone = first_data_zone;
 814#ifndef BEQUIET
 815	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
 816		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
 817	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
 818	if(sbi->s_high_sierra)
 819		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
 820#endif
 821
 822	/*
 823	 * If the Joliet level is set, we _may_ decide to use the
 824	 * secondary descriptor, but can't be sure until after we
 825	 * read the root inode. But before reading the root inode
 826	 * we may need to change the device blocksize, and would
 827	 * rather release the old buffer first. So, we cache the
 828	 * first_data_zone value from the secondary descriptor.
 829	 */
 830	if (joliet_level) {
 831		pri = (struct iso_primary_descriptor *) sec;
 832		rootp = (struct iso_directory_record *)
 833			pri->root_directory_record;
 834		first_data_zone = isonum_733(rootp->extent) +
 835				isonum_711(rootp->ext_attr_length);
 836	}
 837
 838	/*
 839	 * We're all done using the volume descriptor, and may need
 840	 * to change the device blocksize, so release the buffer now.
 841	 */
 842	brelse(pri_bh);
 843	brelse(bh);
 844
 845	/*
 846	 * Force the blocksize to 512 for 512 byte sectors.  The file
 847	 * read primitives really get it wrong in a bad way if we don't
 848	 * do this.
 849	 *
 850	 * Note - we should never be setting the blocksize to something
 851	 * less than the hardware sector size for the device.  If we
 852	 * do, we would end up having to read larger buffers and split
 853	 * out portions to satisfy requests.
 854	 *
 855	 * Note2- the idea here is that we want to deal with the optimal
 856	 * zonesize in the filesystem.  If we have it set to something less,
 857	 * then we have horrible problems with trying to piece together
 858	 * bits of adjacent blocks in order to properly read directory
 859	 * entries.  By forcing the blocksize in this way, we ensure
 860	 * that we will never be required to do this.
 861	 */
 862	sb_set_blocksize(s, orig_zonesize);
 863
 864	sbi->s_nls_iocharset = NULL;
 865
 866#ifdef CONFIG_JOLIET
 867	if (joliet_level) {
 868		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
 869		if (strcmp(p, "utf8") != 0) {
 870			sbi->s_nls_iocharset = opt.iocharset ?
 871				load_nls(opt.iocharset) : load_nls_default();
 872			if (!sbi->s_nls_iocharset)
 873				goto out_freesbi;
 874		}
 875	}
 876#endif
 877	s->s_op = &isofs_sops;
 878	s->s_export_op = &isofs_export_ops;
 879	sbi->s_mapping = opt.map;
 880	sbi->s_rock = (opt.rock ? 2 : 0);
 881	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
 882	sbi->s_cruft = opt.cruft;
 883	sbi->s_hide = opt.hide;
 884	sbi->s_showassoc = opt.showassoc;
 885	sbi->s_uid = opt.uid;
 886	sbi->s_gid = opt.gid;
 887	sbi->s_uid_set = opt.uid_set;
 888	sbi->s_gid_set = opt.gid_set;
 889	sbi->s_nocompress = opt.nocompress;
 890	sbi->s_overriderockperm = opt.overriderockperm;
 891	/*
 892	 * It would be incredibly stupid to allow people to mark every file
 893	 * on the disk as suid, so we merely allow them to set the default
 894	 * permissions.
 895	 */
 896	if (opt.fmode != ISOFS_INVALID_MODE)
 897		sbi->s_fmode = opt.fmode & 0777;
 898	else
 899		sbi->s_fmode = ISOFS_INVALID_MODE;
 900	if (opt.dmode != ISOFS_INVALID_MODE)
 901		sbi->s_dmode = opt.dmode & 0777;
 902	else
 903		sbi->s_dmode = ISOFS_INVALID_MODE;
 904
 905	/*
 906	 * Read the root inode, which _may_ result in changing
 907	 * the s_rock flag. Once we have the final s_rock value,
 908	 * we then decide whether to use the Joliet descriptor.
 909	 */
 910	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
 911
 912	/*
 913	 * Fix for broken CDs with a corrupt root inode but a correct Joliet
 914	 * root directory.
 915	 */
 916	if (IS_ERR(inode)) {
 917		if (joliet_level && sbi->s_firstdatazone != first_data_zone) {
 918			printk(KERN_NOTICE
 919			       "ISOFS: root inode is unusable. "
 920			       "Disabling Rock Ridge and switching to Joliet.");
 921			sbi->s_rock = 0;
 922			inode = NULL;
 923		} else {
 924			goto out_no_root;
 925		}
 926	}
 927
 928	/*
 929	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
 930	 * correct Joliet root directory.
 931	 */
 932	if (sbi->s_rock == 1 && joliet_level &&
 933				rootdir_empty(s, sbi->s_firstdatazone)) {
 934		printk(KERN_NOTICE
 935			"ISOFS: primary root directory is empty. "
 936			"Disabling Rock Ridge and switching to Joliet.");
 937		sbi->s_rock = 0;
 938	}
 939
 940	/*
 941	 * If this disk has both Rock Ridge and Joliet on it, then we
 942	 * want to use Rock Ridge by default.  This can be overridden
 943	 * by using the norock mount option.  There is still one other
 944	 * possibility that is not taken into account: a Rock Ridge
 945	 * CD with Unicode names.  Until someone sees such a beast, it
 946	 * will not be supported.
 947	 */
 948	if (sbi->s_rock == 1) {
 949		joliet_level = 0;
 950	} else if (joliet_level) {
 951		sbi->s_rock = 0;
 952		if (sbi->s_firstdatazone != first_data_zone) {
 953			sbi->s_firstdatazone = first_data_zone;
 954			printk(KERN_DEBUG
 955				"ISOFS: changing to secondary root\n");
 956			iput(inode);
 957			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
 958			if (IS_ERR(inode))
 959				goto out_no_root;
 960		}
 961	}
 962
 963	if (opt.check == 'u') {
 964		/* Only Joliet is case insensitive by default */
 965		if (joliet_level)
 966			opt.check = 'r';
 967		else
 968			opt.check = 's';
 969	}
 970	sbi->s_joliet_level = joliet_level;
 971
 972	/* Make sure the root inode is a directory */
 973	if (!S_ISDIR(inode->i_mode)) {
 974		printk(KERN_WARNING
 975			"isofs_fill_super: root inode is not a directory. "
 976			"Corrupted media?\n");
 977		goto out_iput;
 978	}
 979
 980	table = 0;
 981	if (joliet_level)
 982		table += 2;
 983	if (opt.check == 'r')
 984		table++;
 985	sbi->s_check = opt.check;
 986
 987	if (table)
 988		s->s_d_op = &isofs_dentry_ops[table - 1];
 989
 990	/* get the root dentry */
 991	s->s_root = d_make_root(inode);
 992	if (!(s->s_root)) {
 993		error = -ENOMEM;
 994		goto out_no_inode;
 995	}
 996
 997	kfree(opt.iocharset);
 998
 999	return 0;
1000
1001	/*
1002	 * Display error messages and free resources.
1003	 */
1004out_iput:
1005	iput(inode);
1006	goto out_no_inode;
1007out_no_root:
1008	error = PTR_ERR(inode);
1009	if (error != -ENOMEM)
1010		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
1011out_no_inode:
1012#ifdef CONFIG_JOLIET
1013	unload_nls(sbi->s_nls_iocharset);
1014#endif
1015	goto out_freesbi;
1016out_no_read:
1017	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
1018		__func__, s->s_id, iso_blknum, block);
1019	goto out_freebh;
1020out_bad_zone_size:
1021	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1022		sbi->s_log_zone_size);
1023	goto out_freebh;
1024out_bad_size:
1025	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1026		orig_zonesize, opt.blocksize);
1027	goto out_freebh;
1028out_unknown_format:
1029	if (!silent)
1030		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1031
1032out_freebh:
1033	brelse(bh);
1034	brelse(pri_bh);
1035out_freesbi:
1036	kfree(opt.iocharset);
1037	kfree(sbi);
1038	s->s_fs_info = NULL;
1039	return error;
1040}
1041
1042static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1043{
1044	struct super_block *sb = dentry->d_sb;
1045	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1046
1047	buf->f_type = ISOFS_SUPER_MAGIC;
1048	buf->f_bsize = sb->s_blocksize;
1049	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1050		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1051	buf->f_bfree = 0;
1052	buf->f_bavail = 0;
1053	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1054	buf->f_ffree = 0;
1055	buf->f_fsid = u64_to_fsid(id);
1056	buf->f_namelen = NAME_MAX;
1057	return 0;
1058}
1059
1060/*
1061 * Get a set of blocks; filling in buffer_heads if already allocated
1062 * or getblk() if they are not.  Returns the number of blocks inserted
1063 * (-ve == error.)
1064 */
1065int isofs_get_blocks(struct inode *inode, sector_t iblock,
1066		     struct buffer_head **bh, unsigned long nblocks)
1067{
1068	unsigned long b_off = iblock;
1069	unsigned offset, sect_size;
1070	unsigned int firstext;
1071	unsigned long nextblk, nextoff;
1072	int section, rv, error;
1073	struct iso_inode_info *ei = ISOFS_I(inode);
1074
1075	error = -EIO;
1076	rv = 0;
1077	if (iblock != b_off) {
1078		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1079		goto abort;
1080	}
1081
1082
1083	offset = 0;
1084	firstext = ei->i_first_extent;
1085	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1086	nextblk = ei->i_next_section_block;
1087	nextoff = ei->i_next_section_offset;
1088	section = 0;
1089
1090	while (nblocks) {
1091		/* If we are *way* beyond the end of the file, print a message.
1092		 * Access beyond the end of the file up to the next page boundary
1093		 * is normal, however because of the way the page cache works.
1094		 * In this case, we just return 0 so that we can properly fill
1095		 * the page with useless information without generating any
1096		 * I/O errors.
1097		 */
1098		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1099			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1100				__func__, b_off,
1101				(unsigned long long)inode->i_size);
1102			goto abort;
1103		}
1104
1105		/* On the last section, nextblk == 0, section size is likely to
1106		 * exceed sect_size by a partial block, and access beyond the
1107		 * end of the file will reach beyond the section size, too.
1108		 */
1109		while (nextblk && (b_off >= (offset + sect_size))) {
1110			struct inode *ninode;
1111
1112			offset += sect_size;
1113			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1114			if (IS_ERR(ninode)) {
1115				error = PTR_ERR(ninode);
1116				goto abort;
1117			}
1118			firstext  = ISOFS_I(ninode)->i_first_extent;
1119			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1120			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1121			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1122			iput(ninode);
1123
1124			if (++section > 100) {
1125				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1126					" aborting...\n", __func__);
1127				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1128					"nextblk=%lu nextoff=%lu\n", __func__,
1129					b_off, firstext, (unsigned) sect_size,
1130					nextblk, nextoff);
1131				goto abort;
1132			}
1133		}
1134
1135		if (*bh) {
1136			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1137		} else {
1138			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1139			if (!*bh)
1140				goto abort;
1141		}
1142		bh++;	/* Next buffer head */
1143		b_off++;	/* Next buffer offset */
1144		nblocks--;
1145		rv++;
1146	}
1147
1148	error = 0;
1149abort:
1150	return rv != 0 ? rv : error;
1151}
1152
1153/*
1154 * Used by the standard interfaces.
1155 */
1156static int isofs_get_block(struct inode *inode, sector_t iblock,
1157		    struct buffer_head *bh_result, int create)
1158{
1159	int ret;
1160
1161	if (create) {
1162		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1163		return -EROFS;
1164	}
1165
1166	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1167	return ret < 0 ? ret : 0;
1168}
1169
1170static int isofs_bmap(struct inode *inode, sector_t block)
1171{
1172	struct buffer_head dummy;
1173	int error;
1174
1175	dummy.b_state = 0;
1176	dummy.b_blocknr = -1000;
1177	error = isofs_get_block(inode, block, &dummy, 0);
1178	if (!error)
1179		return dummy.b_blocknr;
1180	return 0;
1181}
1182
1183struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1184{
1185	sector_t blknr = isofs_bmap(inode, block);
1186	if (!blknr)
1187		return NULL;
1188	return sb_bread(inode->i_sb, blknr);
1189}
1190
1191static int isofs_read_folio(struct file *file, struct folio *folio)
1192{
1193	return mpage_read_folio(folio, isofs_get_block);
1194}
1195
1196static void isofs_readahead(struct readahead_control *rac)
1197{
1198	mpage_readahead(rac, isofs_get_block);
1199}
1200
1201static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1202{
1203	return generic_block_bmap(mapping,block,isofs_get_block);
1204}
1205
1206static const struct address_space_operations isofs_aops = {
1207	.read_folio = isofs_read_folio,
1208	.readahead = isofs_readahead,
1209	.bmap = _isofs_bmap
1210};
1211
1212static int isofs_read_level3_size(struct inode *inode)
1213{
1214	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1215	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1216	struct buffer_head *bh = NULL;
1217	unsigned long block, offset, block_saved, offset_saved;
1218	int i = 0;
1219	int more_entries = 0;
1220	struct iso_directory_record *tmpde = NULL;
1221	struct iso_inode_info *ei = ISOFS_I(inode);
1222
1223	inode->i_size = 0;
1224
1225	/* The first 16 blocks are reserved as the System Area.  Thus,
1226	 * no inodes can appear in block 0.  We use this to flag that
1227	 * this is the last section. */
1228	ei->i_next_section_block = 0;
1229	ei->i_next_section_offset = 0;
1230
1231	block = ei->i_iget5_block;
1232	offset = ei->i_iget5_offset;
1233
1234	do {
1235		struct iso_directory_record *de;
1236		unsigned int de_len;
1237
1238		if (!bh) {
1239			bh = sb_bread(inode->i_sb, block);
1240			if (!bh)
1241				goto out_noread;
1242		}
1243		de = (struct iso_directory_record *) (bh->b_data + offset);
1244		de_len = *(unsigned char *) de;
1245
1246		if (de_len == 0) {
1247			brelse(bh);
1248			bh = NULL;
1249			++block;
1250			offset = 0;
1251			continue;
1252		}
1253
1254		block_saved = block;
1255		offset_saved = offset;
1256		offset += de_len;
1257
1258		/* Make sure we have a full directory entry */
1259		if (offset >= bufsize) {
1260			int slop = bufsize - offset + de_len;
1261			if (!tmpde) {
1262				tmpde = kmalloc(256, GFP_KERNEL);
1263				if (!tmpde)
1264					goto out_nomem;
1265			}
1266			memcpy(tmpde, de, slop);
1267			offset &= bufsize - 1;
1268			block++;
1269			brelse(bh);
1270			bh = NULL;
1271			if (offset) {
1272				bh = sb_bread(inode->i_sb, block);
1273				if (!bh)
1274					goto out_noread;
1275				memcpy((void *)tmpde+slop, bh->b_data, offset);
1276			}
1277			de = tmpde;
1278		}
1279
1280		inode->i_size += isonum_733(de->size);
1281		if (i == 1) {
1282			ei->i_next_section_block = block_saved;
1283			ei->i_next_section_offset = offset_saved;
1284		}
1285
1286		more_entries = de->flags[-high_sierra] & 0x80;
1287
1288		i++;
1289		if (i > 100)
1290			goto out_toomany;
1291	} while (more_entries);
1292out:
1293	kfree(tmpde);
1294	brelse(bh);
1295	return 0;
1296
1297out_nomem:
1298	brelse(bh);
1299	return -ENOMEM;
1300
1301out_noread:
1302	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1303	kfree(tmpde);
1304	return -EIO;
1305
1306out_toomany:
1307	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1308		"isofs_read_level3_size: inode=%lu\n",
1309		__func__, inode->i_ino);
1310	goto out;
1311}
1312
1313static int isofs_read_inode(struct inode *inode, int relocated)
1314{
1315	struct super_block *sb = inode->i_sb;
1316	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1317	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1318	unsigned long block;
1319	int high_sierra = sbi->s_high_sierra;
1320	struct buffer_head *bh;
1321	struct iso_directory_record *de;
1322	struct iso_directory_record *tmpde = NULL;
1323	unsigned int de_len;
1324	unsigned long offset;
1325	struct iso_inode_info *ei = ISOFS_I(inode);
1326	int ret = -EIO;
1327
1328	block = ei->i_iget5_block;
1329	bh = sb_bread(inode->i_sb, block);
1330	if (!bh)
1331		goto out_badread;
1332
1333	offset = ei->i_iget5_offset;
1334
1335	de = (struct iso_directory_record *) (bh->b_data + offset);
1336	de_len = *(unsigned char *) de;
1337	if (de_len < sizeof(struct iso_directory_record))
1338		goto fail;
1339
1340	if (offset + de_len > bufsize) {
1341		int frag1 = bufsize - offset;
1342
1343		tmpde = kmalloc(de_len, GFP_KERNEL);
1344		if (!tmpde) {
1345			ret = -ENOMEM;
1346			goto fail;
1347		}
1348		memcpy(tmpde, bh->b_data + offset, frag1);
1349		brelse(bh);
1350		bh = sb_bread(inode->i_sb, ++block);
1351		if (!bh)
1352			goto out_badread;
1353		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1354		de = tmpde;
1355	}
1356
1357	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1358					ei->i_iget5_offset,
1359					ISOFS_BUFFER_BITS(inode));
1360
1361	/* Assume it is a normal-format file unless told otherwise */
1362	ei->i_file_format = isofs_file_normal;
1363
1364	if (de->flags[-high_sierra] & 2) {
1365		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1366			inode->i_mode = S_IFDIR | sbi->s_dmode;
1367		else
1368			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1369		set_nlink(inode, 1);	/*
1370					 * Set to 1.  We know there are 2, but
1371					 * the find utility tries to optimize
1372					 * if it is 2, and it screws up.  It is
1373					 * easier to give 1 which tells find to
1374					 * do it the hard way.
1375					 */
1376	} else {
1377		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1378			inode->i_mode = S_IFREG | sbi->s_fmode;
1379		} else {
1380			/*
1381			 * Set default permissions: r-x for all.  The disc
1382			 * could be shared with DOS machines so virtually
1383			 * anything could be a valid executable.
1384			 */
1385			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1386		}
1387		set_nlink(inode, 1);
1388	}
1389	inode->i_uid = sbi->s_uid;
1390	inode->i_gid = sbi->s_gid;
1391	inode->i_blocks = 0;
1392
1393	ei->i_format_parm[0] = 0;
1394	ei->i_format_parm[1] = 0;
1395	ei->i_format_parm[2] = 0;
1396
1397	ei->i_section_size = isonum_733(de->size);
1398	if (de->flags[-high_sierra] & 0x80) {
1399		ret = isofs_read_level3_size(inode);
1400		if (ret < 0)
1401			goto fail;
1402		ret = -EIO;
1403	} else {
1404		ei->i_next_section_block = 0;
1405		ei->i_next_section_offset = 0;
1406		inode->i_size = isonum_733(de->size);
1407	}
1408
1409	/*
1410	 * Some dipshit decided to store some other bit of information
1411	 * in the high byte of the file length.  Truncate size in case
1412	 * this CDROM was mounted with the cruft option.
1413	 */
1414
1415	if (sbi->s_cruft)
1416		inode->i_size &= 0x00ffffff;
1417
1418	if (de->interleave[0]) {
1419		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1420		inode->i_size = 0;
1421	}
1422
1423	/* I have no idea what file_unit_size is used for, so
1424	   we will flag it for now */
1425	if (de->file_unit_size[0] != 0) {
1426		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1427			inode->i_ino);
1428	}
1429
1430	/* I have no idea what other flag bits are used for, so
1431	   we will flag it for now */
1432#ifdef DEBUG
1433	if((de->flags[-high_sierra] & ~2)!= 0){
1434		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1435				"(%ld %x).\n",
1436			inode->i_ino, de->flags[-high_sierra]);
1437	}
1438#endif
1439	inode_set_mtime_to_ts(inode,
1440			      inode_set_atime_to_ts(inode, inode_set_ctime(inode, iso_date(de->date, high_sierra), 0)));
1441
1442	ei->i_first_extent = (isonum_733(de->extent) +
1443			isonum_711(de->ext_attr_length));
1444
1445	/* Set the number of blocks for stat() - should be done before RR */
1446	inode->i_blocks = (inode->i_size + 511) >> 9;
1447
1448	/*
1449	 * Now test for possible Rock Ridge extensions which will override
1450	 * some of these numbers in the inode structure.
1451	 */
1452
1453	if (!high_sierra) {
1454		parse_rock_ridge_inode(de, inode, relocated);
1455		/* if we want uid/gid set, override the rock ridge setting */
1456		if (sbi->s_uid_set)
1457			inode->i_uid = sbi->s_uid;
1458		if (sbi->s_gid_set)
1459			inode->i_gid = sbi->s_gid;
1460	}
1461	/* Now set final access rights if overriding rock ridge setting */
1462	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1463	    sbi->s_dmode != ISOFS_INVALID_MODE)
1464		inode->i_mode = S_IFDIR | sbi->s_dmode;
1465	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1466	    sbi->s_fmode != ISOFS_INVALID_MODE)
1467		inode->i_mode = S_IFREG | sbi->s_fmode;
1468
1469	/* Install the inode operations vector */
1470	if (S_ISREG(inode->i_mode)) {
1471		inode->i_fop = &generic_ro_fops;
1472		switch (ei->i_file_format) {
1473#ifdef CONFIG_ZISOFS
1474		case isofs_file_compressed:
1475			inode->i_data.a_ops = &zisofs_aops;
1476			break;
1477#endif
1478		default:
1479			inode->i_data.a_ops = &isofs_aops;
1480			break;
1481		}
1482	} else if (S_ISDIR(inode->i_mode)) {
1483		inode->i_op = &isofs_dir_inode_operations;
1484		inode->i_fop = &isofs_dir_operations;
1485	} else if (S_ISLNK(inode->i_mode)) {
1486		inode->i_op = &page_symlink_inode_operations;
1487		inode_nohighmem(inode);
1488		inode->i_data.a_ops = &isofs_symlink_aops;
1489	} else
1490		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1491		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1492
1493	ret = 0;
1494out:
1495	kfree(tmpde);
1496	brelse(bh);
1497	return ret;
1498
1499out_badread:
1500	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1501fail:
1502	goto out;
1503}
1504
1505struct isofs_iget5_callback_data {
1506	unsigned long block;
1507	unsigned long offset;
1508};
1509
1510static int isofs_iget5_test(struct inode *ino, void *data)
1511{
1512	struct iso_inode_info *i = ISOFS_I(ino);
1513	struct isofs_iget5_callback_data *d =
1514		(struct isofs_iget5_callback_data*)data;
1515	return (i->i_iget5_block == d->block)
1516		&& (i->i_iget5_offset == d->offset);
1517}
1518
1519static int isofs_iget5_set(struct inode *ino, void *data)
1520{
1521	struct iso_inode_info *i = ISOFS_I(ino);
1522	struct isofs_iget5_callback_data *d =
1523		(struct isofs_iget5_callback_data*)data;
1524	i->i_iget5_block = d->block;
1525	i->i_iget5_offset = d->offset;
1526	return 0;
1527}
1528
1529/* Store, in the inode's containing structure, the block and block
1530 * offset that point to the underlying meta-data for the inode.  The
1531 * code below is otherwise similar to the iget() code in
1532 * include/linux/fs.h */
1533struct inode *__isofs_iget(struct super_block *sb,
1534			   unsigned long block,
1535			   unsigned long offset,
1536			   int relocated)
1537{
1538	unsigned long hashval;
1539	struct inode *inode;
1540	struct isofs_iget5_callback_data data;
1541	long ret;
1542
1543	if (offset >= 1ul << sb->s_blocksize_bits)
1544		return ERR_PTR(-EINVAL);
1545
1546	data.block = block;
1547	data.offset = offset;
1548
1549	hashval = (block << sb->s_blocksize_bits) | offset;
1550
1551	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1552				&isofs_iget5_set, &data);
1553
1554	if (!inode)
1555		return ERR_PTR(-ENOMEM);
1556
1557	if (inode->i_state & I_NEW) {
1558		ret = isofs_read_inode(inode, relocated);
1559		if (ret < 0) {
1560			iget_failed(inode);
1561			inode = ERR_PTR(ret);
1562		} else {
1563			unlock_new_inode(inode);
1564		}
1565	}
1566
1567	return inode;
1568}
1569
1570static struct dentry *isofs_mount(struct file_system_type *fs_type,
1571	int flags, const char *dev_name, void *data)
1572{
1573	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1574}
1575
1576static struct file_system_type iso9660_fs_type = {
1577	.owner		= THIS_MODULE,
1578	.name		= "iso9660",
1579	.mount		= isofs_mount,
1580	.kill_sb	= kill_block_super,
1581	.fs_flags	= FS_REQUIRES_DEV,
1582};
1583MODULE_ALIAS_FS("iso9660");
1584MODULE_ALIAS("iso9660");
1585
1586static int __init init_iso9660_fs(void)
1587{
1588	int err = init_inodecache();
1589	if (err)
1590		goto out;
1591#ifdef CONFIG_ZISOFS
1592	err = zisofs_init();
1593	if (err)
1594		goto out1;
1595#endif
1596	err = register_filesystem(&iso9660_fs_type);
1597	if (err)
1598		goto out2;
1599	return 0;
1600out2:
1601#ifdef CONFIG_ZISOFS
1602	zisofs_cleanup();
1603out1:
1604#endif
1605	destroy_inodecache();
1606out:
1607	return err;
1608}
1609
1610static void __exit exit_iso9660_fs(void)
1611{
1612        unregister_filesystem(&iso9660_fs_type);
1613#ifdef CONFIG_ZISOFS
1614	zisofs_cleanup();
1615#endif
1616	destroy_inodecache();
1617}
1618
1619module_init(init_iso9660_fs)
1620module_exit(exit_iso9660_fs)
1621MODULE_LICENSE("GPL");