super.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  linux/fs/ext2/super.c
   4 *
   5 * Copyright (C) 1992, 1993, 1994, 1995
   6 * Remy Card (card@masi.ibp.fr)
   7 * Laboratoire MASI - Institut Blaise Pascal
   8 * Universite Pierre et Marie Curie (Paris VI)
   9 *
  10 *  from
  11 *
  12 *  linux/fs/minix/inode.c
  13 *
  14 *  Copyright (C) 1991, 1992  Linus Torvalds
  15 *
  16 *  Big-endian to little-endian byte-swapping/bitmaps by
  17 *        David S. Miller (davem@caip.rutgers.edu), 1995
  18 */
  19
  20#include <linux/module.h>
  21#include <linux/string.h>
  22#include <linux/fs.h>
  23#include <linux/slab.h>
  24#include <linux/init.h>
  25#include <linux/blkdev.h>
  26#include <linux/fs_context.h>
  27#include <linux/fs_parser.h>
  28#include <linux/random.h>
  29#include <linux/buffer_head.h>
  30#include <linux/exportfs.h>
  31#include <linux/vfs.h>
  32#include <linux/seq_file.h>
  33#include <linux/mount.h>
  34#include <linux/log2.h>
  35#include <linux/quotaops.h>
  36#include <linux/uaccess.h>
  37#include <linux/dax.h>
  38#include <linux/iversion.h>
  39#include "ext2.h"
  40#include "xattr.h"
  41#include "acl.h"
  42
  43static void ext2_write_super(struct super_block *sb);
  44static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
  45static int ext2_sync_fs(struct super_block *sb, int wait);
  46static int ext2_freeze(struct super_block *sb);
  47static int ext2_unfreeze(struct super_block *sb);
  48
  49void ext2_error(struct super_block *sb, const char *function,
  50		const char *fmt, ...)
  51{
  52	struct va_format vaf;
  53	va_list args;
  54	struct ext2_sb_info *sbi = EXT2_SB(sb);
  55	struct ext2_super_block *es = sbi->s_es;
  56
  57	if (!sb_rdonly(sb)) {
  58		spin_lock(&sbi->s_lock);
  59		sbi->s_mount_state |= EXT2_ERROR_FS;
  60		es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
  61		spin_unlock(&sbi->s_lock);
  62		ext2_sync_super(sb, es, 1);
  63	}
  64
  65	va_start(args, fmt);
  66
  67	vaf.fmt = fmt;
  68	vaf.va = &args;
  69
  70	printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
  71	       sb->s_id, function, &vaf);
  72
  73	va_end(args);
  74
  75	if (test_opt(sb, ERRORS_PANIC))
  76		panic("EXT2-fs: panic from previous error\n");
  77	if (!sb_rdonly(sb) && test_opt(sb, ERRORS_RO)) {
  78		ext2_msg(sb, KERN_CRIT,
  79			     "error: remounting filesystem read-only");
  80		sb->s_flags |= SB_RDONLY;
  81	}
  82}
  83
  84static void ext2_msg_fc(struct fs_context *fc, const char *prefix,
  85			const char *fmt, ...)
  86{
  87	struct va_format vaf;
  88	va_list args;
  89	const char *s_id;
  90
  91	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
  92		s_id = fc->root->d_sb->s_id;
  93	} else {
  94		/* get last path component of source */
  95		s_id = strrchr(fc->source, '/');
  96		if (s_id)
  97			s_id++;
  98		else
  99			s_id = fc->source;
 100	}
 101	va_start(args, fmt);
 102
 103	vaf.fmt = fmt;
 104	vaf.va = &args;
 105
 106	printk("%sEXT2-fs (%s): %pV\n", prefix, s_id, &vaf);
 107
 108	va_end(args);
 109}
 110
 111void ext2_msg(struct super_block *sb, const char *prefix,
 112		const char *fmt, ...)
 113{
 114	struct va_format vaf;
 115	va_list args;
 116
 117	va_start(args, fmt);
 118
 119	vaf.fmt = fmt;
 120	vaf.va = &args;
 121
 122	printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 123
 124	va_end(args);
 125}
 126
 127/*
 128 * This must be called with sbi->s_lock held.
 129 */
 130void ext2_update_dynamic_rev(struct super_block *sb)
 131{
 132	struct ext2_super_block *es = EXT2_SB(sb)->s_es;
 133
 134	if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
 135		return;
 136
 137	ext2_msg(sb, KERN_WARNING,
 138		     "warning: updating to rev %d because of "
 139		     "new feature flag, running e2fsck is recommended",
 140		     EXT2_DYNAMIC_REV);
 141
 142	es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
 143	es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
 144	es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
 145	/* leave es->s_feature_*compat flags alone */
 146	/* es->s_uuid will be set by e2fsck if empty */
 147
 148	/*
 149	 * The rest of the superblock fields should be zero, and if not it
 150	 * means they are likely already in use, so leave them alone.  We
 151	 * can leave it up to e2fsck to clean up any inconsistencies there.
 152	 */
 153}
 154
 155#ifdef CONFIG_QUOTA
 156static int ext2_quota_off(struct super_block *sb, int type);
 157
 158static void ext2_quota_off_umount(struct super_block *sb)
 159{
 160	int type;
 161
 162	for (type = 0; type < MAXQUOTAS; type++)
 163		ext2_quota_off(sb, type);
 164}
 165#else
 166static inline void ext2_quota_off_umount(struct super_block *sb)
 167{
 168}
 169#endif
 170
 171static void ext2_put_super (struct super_block * sb)
 172{
 173	int db_count;
 174	int i;
 175	struct ext2_sb_info *sbi = EXT2_SB(sb);
 176
 177	ext2_quota_off_umount(sb);
 178
 179	ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
 180	sbi->s_ea_block_cache = NULL;
 181
 182	if (!sb_rdonly(sb)) {
 183		struct ext2_super_block *es = sbi->s_es;
 184
 185		spin_lock(&sbi->s_lock);
 186		es->s_state = cpu_to_le16(sbi->s_mount_state);
 187		spin_unlock(&sbi->s_lock);
 188		ext2_sync_super(sb, es, 1);
 189	}
 190	db_count = sbi->s_gdb_count;
 191	for (i = 0; i < db_count; i++)
 192		brelse(sbi->s_group_desc[i]);
 193	kvfree(sbi->s_group_desc);
 194	kfree(sbi->s_debts);
 195	percpu_counter_destroy(&sbi->s_freeblocks_counter);
 196	percpu_counter_destroy(&sbi->s_freeinodes_counter);
 197	percpu_counter_destroy(&sbi->s_dirs_counter);
 198	brelse (sbi->s_sbh);
 199	sb->s_fs_info = NULL;
 200	kfree(sbi->s_blockgroup_lock);
 201	fs_put_dax(sbi->s_daxdev, NULL);
 202	kfree(sbi);
 203}
 204
 205static struct kmem_cache * ext2_inode_cachep;
 206
 207static struct inode *ext2_alloc_inode(struct super_block *sb)
 208{
 209	struct ext2_inode_info *ei;
 210	ei = alloc_inode_sb(sb, ext2_inode_cachep, GFP_KERNEL);
 211	if (!ei)
 212		return NULL;
 213	ei->i_block_alloc_info = NULL;
 214	inode_set_iversion(&ei->vfs_inode, 1);
 215#ifdef CONFIG_QUOTA
 216	memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 217#endif
 218
 219	return &ei->vfs_inode;
 220}
 221
 222static void ext2_free_in_core_inode(struct inode *inode)
 223{
 224	kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
 225}
 226
 227static void init_once(void *foo)
 228{
 229	struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
 230
 231	rwlock_init(&ei->i_meta_lock);
 232#ifdef CONFIG_EXT2_FS_XATTR
 233	init_rwsem(&ei->xattr_sem);
 234#endif
 235	mutex_init(&ei->truncate_mutex);
 236	inode_init_once(&ei->vfs_inode);
 237}
 238
 239static int __init init_inodecache(void)
 240{
 241	ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache",
 242				sizeof(struct ext2_inode_info), 0,
 243				SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
 244				offsetof(struct ext2_inode_info, i_data),
 245				sizeof_field(struct ext2_inode_info, i_data),
 246				init_once);
 247	if (ext2_inode_cachep == NULL)
 248		return -ENOMEM;
 249	return 0;
 250}
 251
 252static void destroy_inodecache(void)
 253{
 254	/*
 255	 * Make sure all delayed rcu free inodes are flushed before we
 256	 * destroy cache.
 257	 */
 258	rcu_barrier();
 259	kmem_cache_destroy(ext2_inode_cachep);
 260}
 261
 262static int ext2_show_options(struct seq_file *seq, struct dentry *root)
 263{
 264	struct super_block *sb = root->d_sb;
 265	struct ext2_sb_info *sbi = EXT2_SB(sb);
 266	struct ext2_super_block *es = sbi->s_es;
 267	unsigned long def_mount_opts;
 268
 269	spin_lock(&sbi->s_lock);
 270	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 271
 272	if (sbi->s_sb_block != 1)
 273		seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
 274	if (test_opt(sb, MINIX_DF))
 275		seq_puts(seq, ",minixdf");
 276	if (test_opt(sb, GRPID))
 277		seq_puts(seq, ",grpid");
 278	if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
 279		seq_puts(seq, ",nogrpid");
 280	if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
 281	    le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
 282		seq_printf(seq, ",resuid=%u",
 283				from_kuid_munged(&init_user_ns, sbi->s_resuid));
 284	}
 285	if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
 286	    le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
 287		seq_printf(seq, ",resgid=%u",
 288				from_kgid_munged(&init_user_ns, sbi->s_resgid));
 289	}
 290	if (test_opt(sb, ERRORS_RO)) {
 291		int def_errors = le16_to_cpu(es->s_errors);
 292
 293		if (def_errors == EXT2_ERRORS_PANIC ||
 294		    def_errors == EXT2_ERRORS_CONTINUE) {
 295			seq_puts(seq, ",errors=remount-ro");
 296		}
 297	}
 298	if (test_opt(sb, ERRORS_CONT))
 299		seq_puts(seq, ",errors=continue");
 300	if (test_opt(sb, ERRORS_PANIC))
 301		seq_puts(seq, ",errors=panic");
 302	if (test_opt(sb, NO_UID32))
 303		seq_puts(seq, ",nouid32");
 304	if (test_opt(sb, DEBUG))
 305		seq_puts(seq, ",debug");
 306	if (test_opt(sb, OLDALLOC))
 307		seq_puts(seq, ",oldalloc");
 308
 309#ifdef CONFIG_EXT2_FS_XATTR
 310	if (test_opt(sb, XATTR_USER))
 311		seq_puts(seq, ",user_xattr");
 312	if (!test_opt(sb, XATTR_USER) &&
 313	    (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
 314		seq_puts(seq, ",nouser_xattr");
 315	}
 316#endif
 317
 318#ifdef CONFIG_EXT2_FS_POSIX_ACL
 319	if (test_opt(sb, POSIX_ACL))
 320		seq_puts(seq, ",acl");
 321	if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
 322		seq_puts(seq, ",noacl");
 323#endif
 324
 325	if (test_opt(sb, USRQUOTA))
 326		seq_puts(seq, ",usrquota");
 327
 328	if (test_opt(sb, GRPQUOTA))
 329		seq_puts(seq, ",grpquota");
 330
 331	if (test_opt(sb, XIP))
 332		seq_puts(seq, ",xip");
 333
 334	if (test_opt(sb, DAX))
 335		seq_puts(seq, ",dax");
 336
 337	if (!test_opt(sb, RESERVATION))
 338		seq_puts(seq, ",noreservation");
 339
 340	spin_unlock(&sbi->s_lock);
 341	return 0;
 342}
 343
 344#ifdef CONFIG_QUOTA
 345static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
 346static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
 347static int ext2_quota_on(struct super_block *sb, int type, int format_id,
 348			 const struct path *path);
 349static struct dquot __rcu **ext2_get_dquots(struct inode *inode)
 350{
 351	return EXT2_I(inode)->i_dquot;
 352}
 353
 354static const struct quotactl_ops ext2_quotactl_ops = {
 355	.quota_on	= ext2_quota_on,
 356	.quota_off	= ext2_quota_off,
 357	.quota_sync	= dquot_quota_sync,
 358	.get_state	= dquot_get_state,
 359	.set_info	= dquot_set_dqinfo,
 360	.get_dqblk	= dquot_get_dqblk,
 361	.set_dqblk	= dquot_set_dqblk,
 362	.get_nextdqblk	= dquot_get_next_dqblk,
 363};
 364#endif
 365
 366static const struct super_operations ext2_sops = {
 367	.alloc_inode	= ext2_alloc_inode,
 368	.free_inode	= ext2_free_in_core_inode,
 369	.write_inode	= ext2_write_inode,
 370	.evict_inode	= ext2_evict_inode,
 371	.put_super	= ext2_put_super,
 372	.sync_fs	= ext2_sync_fs,
 373	.freeze_fs	= ext2_freeze,
 374	.unfreeze_fs	= ext2_unfreeze,
 375	.statfs		= ext2_statfs,
 376	.show_options	= ext2_show_options,
 377#ifdef CONFIG_QUOTA
 378	.quota_read	= ext2_quota_read,
 379	.quota_write	= ext2_quota_write,
 380	.get_dquots	= ext2_get_dquots,
 381#endif
 382};
 383
 384static struct inode *ext2_nfs_get_inode(struct super_block *sb,
 385		u64 ino, u32 generation)
 386{
 387	struct inode *inode;
 388
 389	if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
 390		return ERR_PTR(-ESTALE);
 391	if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
 392		return ERR_PTR(-ESTALE);
 393
 394	/*
 395	 * ext2_iget isn't quite right if the inode is currently unallocated!
 396	 * However ext2_iget currently does appropriate checks to handle stale
 397	 * inodes so everything is OK.
 398	 */
 399	inode = ext2_iget(sb, ino);
 400	if (IS_ERR(inode))
 401		return ERR_CAST(inode);
 402	if (generation && inode->i_generation != generation) {
 403		/* we didn't find the right inode.. */
 404		iput(inode);
 405		return ERR_PTR(-ESTALE);
 406	}
 407	return inode;
 408}
 409
 410static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
 411		int fh_len, int fh_type)
 412{
 413	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 414				    ext2_nfs_get_inode);
 415}
 416
 417static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
 418		int fh_len, int fh_type)
 419{
 420	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 421				    ext2_nfs_get_inode);
 422}
 423
 424static const struct export_operations ext2_export_ops = {
 425	.encode_fh = generic_encode_ino32_fh,
 426	.fh_to_dentry = ext2_fh_to_dentry,
 427	.fh_to_parent = ext2_fh_to_parent,
 428	.get_parent = ext2_get_parent,
 429};
 430
 431enum {
 432	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, Opt_resgid, Opt_resuid,
 433	Opt_sb, Opt_errors, Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
 434	Opt_nobh, Opt_user_xattr, Opt_acl, Opt_xip, Opt_dax, Opt_ignore,
 435	Opt_quota, Opt_usrquota, Opt_grpquota, Opt_reservation,
 436};
 437
 438static const struct constant_table ext2_param_errors[] = {
 439	{"continue",	EXT2_MOUNT_ERRORS_CONT},
 440	{"panic",	EXT2_MOUNT_ERRORS_PANIC},
 441	{"remount-ro",	EXT2_MOUNT_ERRORS_RO},
 442	{}
 443};
 444
 445static const struct fs_parameter_spec ext2_param_spec[] = {
 446	fsparam_flag	("bsddf", Opt_bsd_df),
 447	fsparam_flag	("minixdf", Opt_minix_df),
 448	fsparam_flag	("grpid", Opt_grpid),
 449	fsparam_flag	("bsdgroups", Opt_grpid),
 450	fsparam_flag	("nogrpid", Opt_nogrpid),
 451	fsparam_flag	("sysvgroups", Opt_nogrpid),
 452	fsparam_gid	("resgid", Opt_resgid),
 453	fsparam_uid	("resuid", Opt_resuid),
 454	fsparam_u32	("sb", Opt_sb),
 455	fsparam_enum	("errors", Opt_errors, ext2_param_errors),
 456	fsparam_flag	("nouid32", Opt_nouid32),
 457	fsparam_flag	("debug", Opt_debug),
 458	fsparam_flag	("oldalloc", Opt_oldalloc),
 459	fsparam_flag	("orlov", Opt_orlov),
 460	fsparam_flag	("nobh", Opt_nobh),
 461	fsparam_flag_no	("user_xattr", Opt_user_xattr),
 462	fsparam_flag_no	("acl", Opt_acl),
 463	fsparam_flag	("xip", Opt_xip),
 464	fsparam_flag	("dax", Opt_dax),
 465	fsparam_flag	("grpquota", Opt_grpquota),
 466	fsparam_flag	("noquota", Opt_ignore),
 467	fsparam_flag	("quota", Opt_quota),
 468	fsparam_flag	("usrquota", Opt_usrquota),
 469	fsparam_flag_no	("reservation", Opt_reservation),
 470	{}
 471};
 472
 473#define EXT2_SPEC_s_resuid                      (1 << 0)
 474#define EXT2_SPEC_s_resgid                      (1 << 1)
 475
 476struct ext2_fs_context {
 477	unsigned long	vals_s_flags;	/* Bits to set in s_flags */
 478	unsigned long	mask_s_flags;	/* Bits changed in s_flags */
 479	unsigned int	vals_s_mount_opt;
 480	unsigned int	mask_s_mount_opt;
 481	kuid_t		s_resuid;
 482	kgid_t		s_resgid;
 483	unsigned long	s_sb_block;
 484	unsigned int	spec;
 485
 486};
 487
 488static inline void ctx_set_mount_opt(struct ext2_fs_context *ctx,
 489				  unsigned long flag)
 490{
 491	ctx->mask_s_mount_opt |= flag;
 492	ctx->vals_s_mount_opt |= flag;
 493}
 494
 495static inline void ctx_clear_mount_opt(struct ext2_fs_context *ctx,
 496				    unsigned long flag)
 497{
 498	ctx->mask_s_mount_opt |= flag;
 499	ctx->vals_s_mount_opt &= ~flag;
 500}
 501
 502static inline unsigned long
 503ctx_test_mount_opt(struct ext2_fs_context *ctx, unsigned long flag)
 504{
 505	return (ctx->vals_s_mount_opt & flag);
 506}
 507
 508static inline bool
 509ctx_parsed_mount_opt(struct ext2_fs_context *ctx, unsigned long flag)
 510{
 511	return (ctx->mask_s_mount_opt & flag);
 512}
 513
 514static void ext2_free_fc(struct fs_context *fc)
 515{
 516	kfree(fc->fs_private);
 517}
 518
 519static int ext2_parse_param(struct fs_context *fc, struct fs_parameter *param)
 520{
 521	struct ext2_fs_context *ctx = fc->fs_private;
 522	int opt;
 523	struct fs_parse_result result;
 524
 525	opt = fs_parse(fc, ext2_param_spec, param, &result);
 526	if (opt < 0)
 527		return opt;
 528
 529	switch (opt) {
 530	case Opt_bsd_df:
 531		ctx_clear_mount_opt(ctx, EXT2_MOUNT_MINIX_DF);
 532		break;
 533	case Opt_minix_df:
 534		ctx_set_mount_opt(ctx, EXT2_MOUNT_MINIX_DF);
 535		break;
 536	case Opt_grpid:
 537		ctx_set_mount_opt(ctx, EXT2_MOUNT_GRPID);
 538		break;
 539	case Opt_nogrpid:
 540		ctx_clear_mount_opt(ctx, EXT2_MOUNT_GRPID);
 541		break;
 542	case Opt_resuid:
 543		ctx->s_resuid = result.uid;
 544		ctx->spec |= EXT2_SPEC_s_resuid;
 545		break;
 546	case Opt_resgid:
 547		ctx->s_resgid = result.gid;
 548		ctx->spec |= EXT2_SPEC_s_resgid;
 549		break;
 550	case Opt_sb:
 551		/* Note that this is silently ignored on remount */
 552		ctx->s_sb_block = result.uint_32;
 553		break;
 554	case Opt_errors:
 555		ctx_clear_mount_opt(ctx, EXT2_MOUNT_ERRORS_MASK);
 556		ctx_set_mount_opt(ctx, result.uint_32);
 557		break;
 558	case Opt_nouid32:
 559		ctx_set_mount_opt(ctx, EXT2_MOUNT_NO_UID32);
 560		break;
 561	case Opt_debug:
 562		ctx_set_mount_opt(ctx, EXT2_MOUNT_DEBUG);
 563		break;
 564	case Opt_oldalloc:
 565		ctx_set_mount_opt(ctx, EXT2_MOUNT_OLDALLOC);
 566		break;
 567	case Opt_orlov:
 568		ctx_clear_mount_opt(ctx, EXT2_MOUNT_OLDALLOC);
 569		break;
 570	case Opt_nobh:
 571		ext2_msg_fc(fc, KERN_INFO, "nobh option not supported\n");
 572		break;
 573#ifdef CONFIG_EXT2_FS_XATTR
 574	case Opt_user_xattr:
 575		if (!result.negated)
 576			ctx_set_mount_opt(ctx, EXT2_MOUNT_XATTR_USER);
 577		else
 578			ctx_clear_mount_opt(ctx, EXT2_MOUNT_XATTR_USER);
 579		break;
 580#else
 581	case Opt_user_xattr:
 582		ext2_msg_fc(fc, KERN_INFO, "(no)user_xattr options not supported");
 583		break;
 584#endif
 585#ifdef CONFIG_EXT2_FS_POSIX_ACL
 586	case Opt_acl:
 587		if (!result.negated)
 588			ctx_set_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL);
 589		else
 590			ctx_clear_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL);
 591		break;
 592#else
 593	case Opt_acl:
 594		ext2_msg_fc(fc, KERN_INFO, "(no)acl options not supported");
 595		break;
 596#endif
 597	case Opt_xip:
 598		ext2_msg_fc(fc, KERN_INFO, "use dax instead of xip");
 599		ctx_set_mount_opt(ctx, EXT2_MOUNT_XIP);
 600		fallthrough;
 601	case Opt_dax:
 602#ifdef CONFIG_FS_DAX
 603		ext2_msg_fc(fc, KERN_WARNING,
 604		    "DAX enabled. Warning: DAX support in ext2 driver is deprecated"
 605		    " and will be removed at the end of 2025. Please use ext4 driver instead.");
 606		ctx_set_mount_opt(ctx, EXT2_MOUNT_DAX);
 607#else
 608		ext2_msg_fc(fc, KERN_INFO, "dax option not supported");
 609#endif
 610		break;
 611
 612#if defined(CONFIG_QUOTA)
 613	case Opt_quota:
 614	case Opt_usrquota:
 615		ctx_set_mount_opt(ctx, EXT2_MOUNT_USRQUOTA);
 616		break;
 617
 618	case Opt_grpquota:
 619		ctx_set_mount_opt(ctx, EXT2_MOUNT_GRPQUOTA);
 620		break;
 621#else
 622	case Opt_quota:
 623	case Opt_usrquota:
 624	case Opt_grpquota:
 625		ext2_msg_fc(fc, KERN_INFO, "quota operations not supported");
 626		break;
 627#endif
 628	case Opt_reservation:
 629		if (!result.negated) {
 630			ctx_set_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
 631			ext2_msg_fc(fc, KERN_INFO, "reservations ON");
 632		} else {
 633			ctx_clear_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
 634			ext2_msg_fc(fc, KERN_INFO, "reservations OFF");
 635		}
 636		break;
 637	case Opt_ignore:
 638		break;
 639	default:
 640		return -EINVAL;
 641	}
 642	return 0;
 643}
 644
 645static int ext2_setup_super (struct super_block * sb,
 646			      struct ext2_super_block * es,
 647			      int read_only)
 648{
 649	int res = 0;
 650	struct ext2_sb_info *sbi = EXT2_SB(sb);
 651
 652	if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
 653		ext2_msg(sb, KERN_ERR,
 654			"error: revision level too high, "
 655			"forcing read-only mode");
 656		res = SB_RDONLY;
 657	}
 658	if (read_only)
 659		return res;
 660	if (!(sbi->s_mount_state & EXT2_VALID_FS))
 661		ext2_msg(sb, KERN_WARNING,
 662			"warning: mounting unchecked fs, "
 663			"running e2fsck is recommended");
 664	else if ((sbi->s_mount_state & EXT2_ERROR_FS))
 665		ext2_msg(sb, KERN_WARNING,
 666			"warning: mounting fs with errors, "
 667			"running e2fsck is recommended");
 668	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
 669		 le16_to_cpu(es->s_mnt_count) >=
 670		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
 671		ext2_msg(sb, KERN_WARNING,
 672			"warning: maximal mount count reached, "
 673			"running e2fsck is recommended");
 674	else if (le32_to_cpu(es->s_checkinterval) &&
 675		(le32_to_cpu(es->s_lastcheck) +
 676			le32_to_cpu(es->s_checkinterval) <=
 677			ktime_get_real_seconds()))
 678		ext2_msg(sb, KERN_WARNING,
 679			"warning: checktime reached, "
 680			"running e2fsck is recommended");
 681	if (!le16_to_cpu(es->s_max_mnt_count))
 682		es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
 683	le16_add_cpu(&es->s_mnt_count, 1);
 684	if (test_opt (sb, DEBUG))
 685		ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, gc=%lu, "
 686			"bpg=%lu, ipg=%lu, mo=%04lx]",
 687			EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
 688			sbi->s_groups_count,
 689			EXT2_BLOCKS_PER_GROUP(sb),
 690			EXT2_INODES_PER_GROUP(sb),
 691			sbi->s_mount_opt);
 692	return res;
 693}
 694
 695static int ext2_check_descriptors(struct super_block *sb)
 696{
 697	int i;
 698	struct ext2_sb_info *sbi = EXT2_SB(sb);
 699
 700	ext2_debug ("Checking group descriptors");
 701
 702	for (i = 0; i < sbi->s_groups_count; i++) {
 703		struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
 704		ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
 705		ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i);
 706
 707		if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
 708		    le32_to_cpu(gdp->bg_block_bitmap) > last_block)
 709		{
 710			ext2_error (sb, "ext2_check_descriptors",
 711				    "Block bitmap for group %d"
 712				    " not in group (block %lu)!",
 713				    i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
 714			return 0;
 715		}
 716		if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
 717		    le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
 718		{
 719			ext2_error (sb, "ext2_check_descriptors",
 720				    "Inode bitmap for group %d"
 721				    " not in group (block %lu)!",
 722				    i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
 723			return 0;
 724		}
 725		if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
 726		    le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
 727		    last_block)
 728		{
 729			ext2_error (sb, "ext2_check_descriptors",
 730				    "Inode table for group %d"
 731				    " not in group (block %lu)!",
 732				    i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
 733			return 0;
 734		}
 735	}
 736	return 1;
 737}
 738
 739/*
 740 * Maximal file size.  There is a direct, and {,double-,triple-}indirect
 741 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
 742 * We need to be 1 filesystem block less than the 2^32 sector limit.
 743 */
 744static loff_t ext2_max_size(int bits)
 745{
 746	loff_t res = EXT2_NDIR_BLOCKS;
 747	int meta_blocks;
 748	unsigned int upper_limit;
 749	unsigned int ppb = 1 << (bits-2);
 750
 751	/* This is calculated to be the largest file size for a
 752	 * dense, file such that the total number of
 753	 * sectors in the file, including data and all indirect blocks,
 754	 * does not exceed 2^32 -1
 755	 * __u32 i_blocks representing the total number of
 756	 * 512 bytes blocks of the file
 757	 */
 758	upper_limit = (1LL << 32) - 1;
 759
 760	/* total blocks in file system block size */
 761	upper_limit >>= (bits - 9);
 762
 763	/* Compute how many blocks we can address by block tree */
 764	res += 1LL << (bits-2);
 765	res += 1LL << (2*(bits-2));
 766	res += 1LL << (3*(bits-2));
 767	/* Compute how many metadata blocks are needed */
 768	meta_blocks = 1;
 769	meta_blocks += 1 + ppb;
 770	meta_blocks += 1 + ppb + ppb * ppb;
 771	/* Does block tree limit file size? */
 772	if (res + meta_blocks <= upper_limit)
 773		goto check_lfs;
 774
 775	res = upper_limit;
 776	/* How many metadata blocks are needed for addressing upper_limit? */
 777	upper_limit -= EXT2_NDIR_BLOCKS;
 778	/* indirect blocks */
 779	meta_blocks = 1;
 780	upper_limit -= ppb;
 781	/* double indirect blocks */
 782	if (upper_limit < ppb * ppb) {
 783		meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb);
 784		res -= meta_blocks;
 785		goto check_lfs;
 786	}
 787	meta_blocks += 1 + ppb;
 788	upper_limit -= ppb * ppb;
 789	/* tripple indirect blocks for the rest */
 790	meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) +
 791		DIV_ROUND_UP(upper_limit, ppb*ppb);
 792	res -= meta_blocks;
 793check_lfs:
 794	res <<= bits;
 795	if (res > MAX_LFS_FILESIZE)
 796		res = MAX_LFS_FILESIZE;
 797
 798	return res;
 799}
 800
 801static unsigned long descriptor_loc(struct super_block *sb,
 802				    unsigned long logic_sb_block,
 803				    int nr)
 804{
 805	struct ext2_sb_info *sbi = EXT2_SB(sb);
 806	unsigned long bg, first_meta_bg;
 807	
 808	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
 809
 810	if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
 811	    nr < first_meta_bg)
 812		return (logic_sb_block + nr + 1);
 813	bg = sbi->s_desc_per_block * nr;
 814
 815	return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg);
 816}
 817
 818/*
 819 * Set all mount options either from defaults on disk, or from parsed
 820 * options. Parsed/specified options override on-disk defaults.
 821 */
 822static void ext2_set_options(struct fs_context *fc, struct ext2_sb_info *sbi)
 823{
 824	struct ext2_fs_context *ctx = fc->fs_private;
 825	struct ext2_super_block *es = sbi->s_es;
 826	unsigned long def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 827
 828	/* Copy parsed mount options to sbi */
 829	sbi->s_mount_opt = ctx->vals_s_mount_opt;
 830
 831	/* Use in-superblock defaults only if not specified during parsing */
 832	if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_DEBUG) &&
 833	    def_mount_opts & EXT2_DEFM_DEBUG)
 834		set_opt(sbi->s_mount_opt, DEBUG);
 835
 836	if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_GRPID) &&
 837	    def_mount_opts & EXT2_DEFM_BSDGROUPS)
 838		set_opt(sbi->s_mount_opt, GRPID);
 839
 840	if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_NO_UID32) &&
 841	    def_mount_opts & EXT2_DEFM_UID16)
 842		set_opt(sbi->s_mount_opt, NO_UID32);
 843
 844#ifdef CONFIG_EXT2_FS_XATTR
 845	if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_XATTR_USER) &&
 846	    def_mount_opts & EXT2_DEFM_XATTR_USER)
 847		set_opt(sbi->s_mount_opt, XATTR_USER);
 848#endif
 849#ifdef CONFIG_EXT2_FS_POSIX_ACL
 850	if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL) &&
 851	    def_mount_opts & EXT2_DEFM_ACL)
 852		set_opt(sbi->s_mount_opt, POSIX_ACL);
 853#endif
 854
 855	if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_ERRORS_MASK)) {
 856		if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
 857			set_opt(sbi->s_mount_opt, ERRORS_PANIC);
 858		else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
 859			set_opt(sbi->s_mount_opt, ERRORS_CONT);
 860		else
 861			set_opt(sbi->s_mount_opt, ERRORS_RO);
 862	}
 863
 864	if (ctx->spec & EXT2_SPEC_s_resuid)
 865		sbi->s_resuid = ctx->s_resuid;
 866	else
 867		sbi->s_resuid = make_kuid(&init_user_ns,
 868					   le16_to_cpu(es->s_def_resuid));
 869
 870	if (ctx->spec & EXT2_SPEC_s_resgid)
 871		sbi->s_resgid = ctx->s_resgid;
 872	else
 873		sbi->s_resgid = make_kgid(&init_user_ns,
 874					   le16_to_cpu(es->s_def_resgid));
 875}
 876
 877static int ext2_fill_super(struct super_block *sb, struct fs_context *fc)
 878{
 879	struct ext2_fs_context *ctx = fc->fs_private;
 880	int silent = fc->sb_flags & SB_SILENT;
 881	struct buffer_head * bh;
 882	struct ext2_sb_info * sbi;
 883	struct ext2_super_block * es;
 884	struct inode *root;
 885	unsigned long block;
 886	unsigned long sb_block = ctx->s_sb_block;
 887	unsigned long logic_sb_block;
 888	unsigned long offset = 0;
 889	long ret = -ENOMEM;
 890	int blocksize = BLOCK_SIZE;
 891	int db_count;
 892	int i, j;
 893	__le32 features;
 894	int err;
 895
 896	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 897	if (!sbi)
 898		return -ENOMEM;
 899
 900	sbi->s_blockgroup_lock =
 901		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
 902	if (!sbi->s_blockgroup_lock) {
 903		kfree(sbi);
 904		return -ENOMEM;
 905	}
 906	sb->s_fs_info = sbi;
 907	sbi->s_sb_block = sb_block;
 908	sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
 909					   NULL, NULL);
 910
 911	spin_lock_init(&sbi->s_lock);
 912	ret = -EINVAL;
 913
 914	/*
 915	 * See what the current blocksize for the device is, and
 916	 * use that as the blocksize.  Otherwise (or if the blocksize
 917	 * is smaller than the default) use the default.
 918	 * This is important for devices that have a hardware
 919	 * sectorsize that is larger than the default.
 920	 */
 921	blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
 922	if (!blocksize) {
 923		ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
 924		goto failed_sbi;
 925	}
 926
 927	/*
 928	 * If the superblock doesn't start on a hardware sector boundary,
 929	 * calculate the offset.  
 930	 */
 931	if (blocksize != BLOCK_SIZE) {
 932		logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
 933		offset = (sb_block*BLOCK_SIZE) % blocksize;
 934	} else {
 935		logic_sb_block = sb_block;
 936	}
 937
 938	if (!(bh = sb_bread(sb, logic_sb_block))) {
 939		ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
 940		goto failed_sbi;
 941	}
 942	/*
 943	 * Note: s_es must be initialized as soon as possible because
 944	 *       some ext2 macro-instructions depend on its value
 945	 */
 946	es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
 947	sbi->s_es = es;
 948	sb->s_magic = le16_to_cpu(es->s_magic);
 949
 950	if (sb->s_magic != EXT2_SUPER_MAGIC)
 951		goto cantfind_ext2;
 952
 953	ext2_set_options(fc, sbi);
 954
 955	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
 956		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
 957	sb->s_iflags |= SB_I_CGROUPWB;
 958
 959	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
 960	    (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
 961	     EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
 962	     EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
 963		ext2_msg(sb, KERN_WARNING,
 964			"warning: feature flags set on rev 0 fs, "
 965			"running e2fsck is recommended");
 966	/*
 967	 * Check feature flags regardless of the revision level, since we
 968	 * previously didn't change the revision level when setting the flags,
 969	 * so there is a chance incompat flags are set on a rev 0 filesystem.
 970	 */
 971	features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
 972	if (features) {
 973		ext2_msg(sb, KERN_ERR,	"error: couldn't mount because of "
 974		       "unsupported optional features (%x)",
 975			le32_to_cpu(features));
 976		goto failed_mount;
 977	}
 978	if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
 979		ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
 980		       "unsupported optional features (%x)",
 981		       le32_to_cpu(features));
 982		goto failed_mount;
 983	}
 984
 985	if (le32_to_cpu(es->s_log_block_size) >
 986	    (EXT2_MAX_BLOCK_LOG_SIZE - BLOCK_SIZE_BITS)) {
 987		ext2_msg(sb, KERN_ERR,
 988			 "Invalid log block size: %u",
 989			 le32_to_cpu(es->s_log_block_size));
 990		goto failed_mount;
 991	}
 992	blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
 993
 994	if (test_opt(sb, DAX)) {
 995		if (!sbi->s_daxdev) {
 996			ext2_msg(sb, KERN_ERR,
 997				"DAX unsupported by block device. Turning off DAX.");
 998			clear_opt(sbi->s_mount_opt, DAX);
 999		} else if (blocksize != PAGE_SIZE) {
1000			ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
1001			clear_opt(sbi->s_mount_opt, DAX);
1002		}
1003	}
1004
1005	/* If the blocksize doesn't match, re-read the thing.. */
1006	if (sb->s_blocksize != blocksize) {
1007		brelse(bh);
1008
1009		if (!sb_set_blocksize(sb, blocksize)) {
1010			ext2_msg(sb, KERN_ERR,
1011				"error: bad blocksize %d", blocksize);
1012			goto failed_sbi;
1013		}
1014
1015		logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
1016		offset = (sb_block*BLOCK_SIZE) % blocksize;
1017		bh = sb_bread(sb, logic_sb_block);
1018		if(!bh) {
1019			ext2_msg(sb, KERN_ERR, "error: couldn't read"
1020				"superblock on 2nd try");
1021			goto failed_sbi;
1022		}
1023		es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
1024		sbi->s_es = es;
1025		if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
1026			ext2_msg(sb, KERN_ERR, "error: magic mismatch");
1027			goto failed_mount;
1028		}
1029	}
1030
1031	sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
1032	sb->s_max_links = EXT2_LINK_MAX;
1033	sb->s_time_min = S32_MIN;
1034	sb->s_time_max = S32_MAX;
1035
1036	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
1037		sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
1038		sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
1039	} else {
1040		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1041		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1042		if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
1043		    !is_power_of_2(sbi->s_inode_size) ||
1044		    (sbi->s_inode_size > blocksize)) {
1045			ext2_msg(sb, KERN_ERR,
1046				"error: unsupported inode size: %d",
1047				sbi->s_inode_size);
1048			goto failed_mount;
1049		}
1050	}
1051
1052	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1053	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1054
1055	sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1056	if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1057		goto cantfind_ext2;
1058	sbi->s_itb_per_group = sbi->s_inodes_per_group /
1059					sbi->s_inodes_per_block;
1060	sbi->s_desc_per_block = sb->s_blocksize /
1061					sizeof (struct ext2_group_desc);
1062	sbi->s_sbh = bh;
1063	sbi->s_mount_state = le16_to_cpu(es->s_state);
1064	sbi->s_addr_per_block_bits =
1065		ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1066	sbi->s_desc_per_block_bits =
1067		ilog2 (EXT2_DESC_PER_BLOCK(sb));
1068
1069	if (sb->s_magic != EXT2_SUPER_MAGIC)
1070		goto cantfind_ext2;
1071
1072	if (sb->s_blocksize != bh->b_size) {
1073		if (!silent)
1074			ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1075		goto failed_mount;
1076	}
1077
1078	if (es->s_log_frag_size != es->s_log_block_size) {
1079		ext2_msg(sb, KERN_ERR,
1080			"error: fragsize log %u != blocksize log %u",
1081			le32_to_cpu(es->s_log_frag_size), sb->s_blocksize_bits);
1082		goto failed_mount;
1083	}
1084
1085	if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1086		ext2_msg(sb, KERN_ERR,
1087			"error: #blocks per group too big: %lu",
1088			sbi->s_blocks_per_group);
1089		goto failed_mount;
1090	}
1091	/* At least inode table, bitmaps, and sb have to fit in one group */
1092	if (sbi->s_blocks_per_group <= sbi->s_itb_per_group + 3) {
1093		ext2_msg(sb, KERN_ERR,
1094			"error: #blocks per group smaller than metadata size: %lu <= %lu",
1095			sbi->s_blocks_per_group, sbi->s_inodes_per_group + 3);
1096		goto failed_mount;
1097	}
1098	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
1099	    sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1100		ext2_msg(sb, KERN_ERR,
1101			"error: invalid #inodes per group: %lu",
1102			sbi->s_inodes_per_group);
1103		goto failed_mount;
1104	}
1105	if (sb_bdev_nr_blocks(sb) < le32_to_cpu(es->s_blocks_count)) {
1106		ext2_msg(sb, KERN_ERR,
1107			 "bad geometry: block count %u exceeds size of device (%u blocks)",
1108			 le32_to_cpu(es->s_blocks_count),
1109			 (unsigned)sb_bdev_nr_blocks(sb));
1110		goto failed_mount;
1111	}
1112
1113	sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1114				le32_to_cpu(es->s_first_data_block) - 1)
1115					/ EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1116	if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group !=
1117	    le32_to_cpu(es->s_inodes_count)) {
1118		ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu",
1119			 le32_to_cpu(es->s_inodes_count),
1120			 (u64)sbi->s_groups_count * sbi->s_inodes_per_group);
1121		goto failed_mount;
1122	}
1123	db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1124		   EXT2_DESC_PER_BLOCK(sb);
1125	sbi->s_group_desc = kvmalloc_array(db_count,
1126					   sizeof(struct buffer_head *),
1127					   GFP_KERNEL);
1128	if (sbi->s_group_desc == NULL) {
1129		ret = -ENOMEM;
1130		ext2_msg(sb, KERN_ERR, "error: not enough memory");
1131		goto failed_mount;
1132	}
1133	bgl_lock_init(sbi->s_blockgroup_lock);
1134	sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1135	if (!sbi->s_debts) {
1136		ret = -ENOMEM;
1137		ext2_msg(sb, KERN_ERR, "error: not enough memory");
1138		goto failed_mount_group_desc;
1139	}
1140	for (i = 0; i < db_count; i++) {
1141		block = descriptor_loc(sb, logic_sb_block, i);
1142		sbi->s_group_desc[i] = sb_bread(sb, block);
1143		if (!sbi->s_group_desc[i]) {
1144			for (j = 0; j < i; j++)
1145				brelse (sbi->s_group_desc[j]);
1146			ext2_msg(sb, KERN_ERR,
1147				"error: unable to read group descriptors");
1148			goto failed_mount_group_desc;
1149		}
1150	}
1151	if (!ext2_check_descriptors (sb)) {
1152		ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1153		goto failed_mount2;
1154	}
1155	sbi->s_gdb_count = db_count;
1156	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1157	spin_lock_init(&sbi->s_next_gen_lock);
1158
1159	/* per filesystem reservation list head & lock */
1160	spin_lock_init(&sbi->s_rsv_window_lock);
1161	sbi->s_rsv_window_root = RB_ROOT;
1162	/*
1163	 * Add a single, static dummy reservation to the start of the
1164	 * reservation window list --- it gives us a placeholder for
1165	 * append-at-start-of-list which makes the allocation logic
1166	 * _much_ simpler.
1167	 */
1168	sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1169	sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1170	sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1171	sbi->s_rsv_window_head.rsv_goal_size = 0;
1172	ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1173
1174	err = percpu_counter_init(&sbi->s_freeblocks_counter,
1175				ext2_count_free_blocks(sb), GFP_KERNEL);
1176	if (!err) {
1177		err = percpu_counter_init(&sbi->s_freeinodes_counter,
1178				ext2_count_free_inodes(sb), GFP_KERNEL);
1179	}
1180	if (!err) {
1181		err = percpu_counter_init(&sbi->s_dirs_counter,
1182				ext2_count_dirs(sb), GFP_KERNEL);
1183	}
1184	if (err) {
1185		ret = err;
1186		ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1187		goto failed_mount3;
1188	}
1189
1190#ifdef CONFIG_EXT2_FS_XATTR
1191	sbi->s_ea_block_cache = ext2_xattr_create_cache();
1192	if (!sbi->s_ea_block_cache) {
1193		ret = -ENOMEM;
1194		ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");
1195		goto failed_mount3;
1196	}
1197#endif
1198	/*
1199	 * set up enough so that it can read an inode
1200	 */
1201	sb->s_op = &ext2_sops;
1202	sb->s_export_op = &ext2_export_ops;
1203	sb->s_xattr = ext2_xattr_handlers;
1204
1205#ifdef CONFIG_QUOTA
1206	sb->dq_op = &dquot_operations;
1207	sb->s_qcop = &ext2_quotactl_ops;
1208	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1209#endif
1210
1211	root = ext2_iget(sb, EXT2_ROOT_INO);
1212	if (IS_ERR(root)) {
1213		ret = PTR_ERR(root);
1214		goto failed_mount3;
1215	}
1216	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1217		iput(root);
1218		ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1219		goto failed_mount3;
1220	}
1221
1222	sb->s_root = d_make_root(root);
1223	if (!sb->s_root) {
1224		ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1225		ret = -ENOMEM;
1226		goto failed_mount3;
1227	}
1228	if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1229		ext2_msg(sb, KERN_WARNING,
1230			"warning: mounting ext3 filesystem as ext2");
1231	if (ext2_setup_super (sb, es, sb_rdonly(sb)))
1232		sb->s_flags |= SB_RDONLY;
1233	ext2_write_super(sb);
1234	return 0;
1235
1236cantfind_ext2:
1237	if (!silent)
1238		ext2_msg(sb, KERN_ERR,
1239			"error: can't find an ext2 filesystem on dev %s.",
1240			sb->s_id);
1241	goto failed_mount;
1242failed_mount3:
1243	ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1244	percpu_counter_destroy(&sbi->s_freeblocks_counter);
1245	percpu_counter_destroy(&sbi->s_freeinodes_counter);
1246	percpu_counter_destroy(&sbi->s_dirs_counter);
1247failed_mount2:
1248	for (i = 0; i < db_count; i++)
1249		brelse(sbi->s_group_desc[i]);
1250failed_mount_group_desc:
1251	kvfree(sbi->s_group_desc);
1252	kfree(sbi->s_debts);
1253failed_mount:
1254	brelse(bh);
1255failed_sbi:
1256	fs_put_dax(sbi->s_daxdev, NULL);
1257	sb->s_fs_info = NULL;
1258	kfree(sbi->s_blockgroup_lock);
1259	kfree(sbi);
1260	return ret;
1261}
1262
1263static void ext2_clear_super_error(struct super_block *sb)
1264{
1265	struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1266
1267	if (buffer_write_io_error(sbh)) {
1268		/*
1269		 * Oh, dear.  A previous attempt to write the
1270		 * superblock failed.  This could happen because the
1271		 * USB device was yanked out.  Or it could happen to
1272		 * be a transient write error and maybe the block will
1273		 * be remapped.  Nothing we can do but to retry the
1274		 * write and hope for the best.
1275		 */
1276		ext2_msg(sb, KERN_ERR,
1277		       "previous I/O error to superblock detected");
1278		clear_buffer_write_io_error(sbh);
1279		set_buffer_uptodate(sbh);
1280	}
1281}
1282
1283void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1284		     int wait)
1285{
1286	ext2_clear_super_error(sb);
1287	spin_lock(&EXT2_SB(sb)->s_lock);
1288	es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1289	es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1290	es->s_wtime = cpu_to_le32(ktime_get_real_seconds());
1291	/* unlock before we do IO */
1292	spin_unlock(&EXT2_SB(sb)->s_lock);
1293	mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1294	if (wait)
1295		sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1296}
1297
1298/*
1299 * In the second extended file system, it is not necessary to
1300 * write the super block since we use a mapping of the
1301 * disk super block in a buffer.
1302 *
1303 * However, this function is still used to set the fs valid
1304 * flags to 0.  We need to set this flag to 0 since the fs
1305 * may have been checked while mounted and e2fsck may have
1306 * set s_state to EXT2_VALID_FS after some corrections.
1307 */
1308static int ext2_sync_fs(struct super_block *sb, int wait)
1309{
1310	struct ext2_sb_info *sbi = EXT2_SB(sb);
1311	struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1312
1313	/*
1314	 * Write quota structures to quota file, sync_blockdev() will write
1315	 * them to disk later
1316	 */
1317	dquot_writeback_dquots(sb, -1);
1318
1319	spin_lock(&sbi->s_lock);
1320	if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1321		ext2_debug("setting valid to 0\n");
1322		es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1323	}
1324	spin_unlock(&sbi->s_lock);
1325	ext2_sync_super(sb, es, wait);
1326	return 0;
1327}
1328
1329static int ext2_freeze(struct super_block *sb)
1330{
1331	struct ext2_sb_info *sbi = EXT2_SB(sb);
1332
1333	/*
1334	 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1335	 * because we have unattached inodes and thus filesystem is not fully
1336	 * consistent.
1337	 */
1338	if (atomic_long_read(&sb->s_remove_count)) {
1339		ext2_sync_fs(sb, 1);
1340		return 0;
1341	}
1342	/* Set EXT2_FS_VALID flag */
1343	spin_lock(&sbi->s_lock);
1344	sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1345	spin_unlock(&sbi->s_lock);
1346	ext2_sync_super(sb, sbi->s_es, 1);
1347
1348	return 0;
1349}
1350
1351static int ext2_unfreeze(struct super_block *sb)
1352{
1353	/* Just write sb to clear EXT2_VALID_FS flag */
1354	ext2_write_super(sb);
1355
1356	return 0;
1357}
1358
1359static void ext2_write_super(struct super_block *sb)
1360{
1361	if (!sb_rdonly(sb))
1362		ext2_sync_fs(sb, 1);
1363}
1364
1365static int ext2_reconfigure(struct fs_context *fc)
1366{
1367	struct ext2_fs_context *ctx = fc->fs_private;
1368	struct super_block *sb = fc->root->d_sb;
1369	struct ext2_sb_info * sbi = EXT2_SB(sb);
1370	struct ext2_super_block * es;
1371	struct ext2_mount_options new_opts;
1372	int flags = fc->sb_flags;
1373	int err;
1374
1375	sync_filesystem(sb);
1376
1377	new_opts.s_mount_opt = ctx->vals_s_mount_opt;
1378	new_opts.s_resuid = ctx->s_resuid;
1379	new_opts.s_resgid = ctx->s_resgid;
1380
1381	spin_lock(&sbi->s_lock);
1382	es = sbi->s_es;
1383	if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1384		ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1385			 "dax flag with busy inodes while remounting");
1386		new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
1387	}
1388	if ((bool)(flags & SB_RDONLY) == sb_rdonly(sb))
1389		goto out_set;
1390	if (flags & SB_RDONLY) {
1391		if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1392		    !(sbi->s_mount_state & EXT2_VALID_FS))
1393			goto out_set;
1394
1395		/*
1396		 * OK, we are remounting a valid rw partition rdonly, so set
1397		 * the rdonly flag and then mark the partition as valid again.
1398		 */
1399		es->s_state = cpu_to_le16(sbi->s_mount_state);
1400		es->s_mtime = cpu_to_le32(ktime_get_real_seconds());
1401		spin_unlock(&sbi->s_lock);
1402
1403		err = dquot_suspend(sb, -1);
1404		if (err < 0)
1405			return err;
1406
1407		ext2_sync_super(sb, es, 1);
1408	} else {
1409		__le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1410					       ~EXT2_FEATURE_RO_COMPAT_SUPP);
1411		if (ret) {
1412			spin_unlock(&sbi->s_lock);
1413			ext2_msg(sb, KERN_WARNING,
1414				"warning: couldn't remount RDWR because of "
1415				"unsupported optional features (%x).",
1416				le32_to_cpu(ret));
1417			return -EROFS;
1418		}
1419		/*
1420		 * Mounting a RDONLY partition read-write, so reread and
1421		 * store the current valid flag.  (It may have been changed
1422		 * by e2fsck since we originally mounted the partition.)
1423		 */
1424		sbi->s_mount_state = le16_to_cpu(es->s_state);
1425		if (!ext2_setup_super (sb, es, 0))
1426			sb->s_flags &= ~SB_RDONLY;
1427		spin_unlock(&sbi->s_lock);
1428
1429		ext2_write_super(sb);
1430
1431		dquot_resume(sb, -1);
1432	}
1433
1434	spin_lock(&sbi->s_lock);
1435out_set:
1436	sbi->s_mount_opt = new_opts.s_mount_opt;
1437	sbi->s_resuid = new_opts.s_resuid;
1438	sbi->s_resgid = new_opts.s_resgid;
1439	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
1440		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
1441	spin_unlock(&sbi->s_lock);
1442
1443	return 0;
1444}
1445
1446static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1447{
1448	struct super_block *sb = dentry->d_sb;
1449	struct ext2_sb_info *sbi = EXT2_SB(sb);
1450	struct ext2_super_block *es = sbi->s_es;
1451
1452	spin_lock(&sbi->s_lock);
1453
1454	if (test_opt (sb, MINIX_DF))
1455		sbi->s_overhead_last = 0;
1456	else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1457		unsigned long i, overhead = 0;
1458		smp_rmb();
1459
1460		/*
1461		 * Compute the overhead (FS structures). This is constant
1462		 * for a given filesystem unless the number of block groups
1463		 * changes so we cache the previous value until it does.
1464		 */
1465
1466		/*
1467		 * All of the blocks before first_data_block are
1468		 * overhead
1469		 */
1470		overhead = le32_to_cpu(es->s_first_data_block);
1471
1472		/*
1473		 * Add the overhead attributed to the superblock and
1474		 * block group descriptors.  If the sparse superblocks
1475		 * feature is turned on, then not all groups have this.
1476		 */
1477		for (i = 0; i < sbi->s_groups_count; i++)
1478			overhead += ext2_bg_has_super(sb, i) +
1479				ext2_bg_num_gdb(sb, i);
1480
1481		/*
1482		 * Every block group has an inode bitmap, a block
1483		 * bitmap, and an inode table.
1484		 */
1485		overhead += (sbi->s_groups_count *
1486			     (2 + sbi->s_itb_per_group));
1487		sbi->s_overhead_last = overhead;
1488		smp_wmb();
1489		sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1490	}
1491
1492	buf->f_type = EXT2_SUPER_MAGIC;
1493	buf->f_bsize = sb->s_blocksize;
1494	buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1495	buf->f_bfree = ext2_count_free_blocks(sb);
1496	es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1497	buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1498	if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1499		buf->f_bavail = 0;
1500	buf->f_files = le32_to_cpu(es->s_inodes_count);
1501	buf->f_ffree = ext2_count_free_inodes(sb);
1502	es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1503	buf->f_namelen = EXT2_NAME_LEN;
1504	buf->f_fsid = uuid_to_fsid(es->s_uuid);
1505	spin_unlock(&sbi->s_lock);
1506	return 0;
1507}
1508
1509static int ext2_get_tree(struct fs_context *fc)
1510{
1511	return get_tree_bdev(fc, ext2_fill_super);
1512}
1513
1514#ifdef CONFIG_QUOTA
1515
1516/* Read data from quotafile - avoid pagecache and such because we cannot afford
1517 * acquiring the locks... As quota files are never truncated and quota code
1518 * itself serializes the operations (and no one else should touch the files)
1519 * we don't have to be afraid of races */
1520static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1521			       size_t len, loff_t off)
1522{
1523	struct inode *inode = sb_dqopt(sb)->files[type];
1524	sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1525	int err = 0;
1526	int offset = off & (sb->s_blocksize - 1);
1527	int tocopy;
1528	size_t toread;
1529	struct buffer_head tmp_bh;
1530	struct buffer_head *bh;
1531	loff_t i_size = i_size_read(inode);
1532
1533	if (off > i_size)
1534		return 0;
1535	if (off+len > i_size)
1536		len = i_size-off;
1537	toread = len;
1538	while (toread > 0) {
1539		tocopy = min_t(size_t, sb->s_blocksize - offset, toread);
1540
1541		tmp_bh.b_state = 0;
1542		tmp_bh.b_size = sb->s_blocksize;
1543		err = ext2_get_block(inode, blk, &tmp_bh, 0);
1544		if (err < 0)
1545			return err;
1546		if (!buffer_mapped(&tmp_bh))	/* A hole? */
1547			memset(data, 0, tocopy);
1548		else {
1549			bh = sb_bread(sb, tmp_bh.b_blocknr);
1550			if (!bh)
1551				return -EIO;
1552			memcpy(data, bh->b_data+offset, tocopy);
1553			brelse(bh);
1554		}
1555		offset = 0;
1556		toread -= tocopy;
1557		data += tocopy;
1558		blk++;
1559	}
1560	return len;
1561}
1562
1563/* Write to quotafile */
1564static ssize_t ext2_quota_write(struct super_block *sb, int type,
1565				const char *data, size_t len, loff_t off)
1566{
1567	struct inode *inode = sb_dqopt(sb)->files[type];
1568	sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1569	int err = 0;
1570	int offset = off & (sb->s_blocksize - 1);
1571	int tocopy;
1572	size_t towrite = len;
1573	struct buffer_head tmp_bh;
1574	struct buffer_head *bh;
1575
1576	while (towrite > 0) {
1577		tocopy = min_t(size_t, sb->s_blocksize - offset, towrite);
1578
1579		tmp_bh.b_state = 0;
1580		tmp_bh.b_size = sb->s_blocksize;
1581		err = ext2_get_block(inode, blk, &tmp_bh, 1);
1582		if (err < 0)
1583			goto out;
1584		if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1585			bh = sb_bread(sb, tmp_bh.b_blocknr);
1586		else
1587			bh = sb_getblk(sb, tmp_bh.b_blocknr);
1588		if (unlikely(!bh)) {
1589			err = -EIO;
1590			goto out;
1591		}
1592		lock_buffer(bh);
1593		memcpy(bh->b_data+offset, data, tocopy);
1594		flush_dcache_folio(bh->b_folio);
1595		set_buffer_uptodate(bh);
1596		mark_buffer_dirty(bh);
1597		unlock_buffer(bh);
1598		brelse(bh);
1599		offset = 0;
1600		towrite -= tocopy;
1601		data += tocopy;
1602		blk++;
1603	}
1604out:
1605	if (len == towrite)
1606		return err;
1607	if (inode->i_size < off+len-towrite)
1608		i_size_write(inode, off+len-towrite);
1609	inode_inc_iversion(inode);
1610	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1611	mark_inode_dirty(inode);
1612	return len - towrite;
1613}
1614
1615static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1616			 const struct path *path)
1617{
1618	int err;
1619	struct inode *inode;
1620
1621	err = dquot_quota_on(sb, type, format_id, path);
1622	if (err)
1623		return err;
1624
1625	inode = d_inode(path->dentry);
1626	inode_lock(inode);
1627	EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1628	inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1629			S_NOATIME | S_IMMUTABLE);
1630	inode_unlock(inode);
1631	mark_inode_dirty(inode);
1632
1633	return 0;
1634}
1635
1636static int ext2_quota_off(struct super_block *sb, int type)
1637{
1638	struct inode *inode = sb_dqopt(sb)->files[type];
1639	int err;
1640
1641	if (!inode || !igrab(inode))
1642		goto out;
1643
1644	err = dquot_quota_off(sb, type);
1645	if (err)
1646		goto out_put;
1647
1648	inode_lock(inode);
1649	EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1650	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1651	inode_unlock(inode);
1652	mark_inode_dirty(inode);
1653out_put:
1654	iput(inode);
1655	return err;
1656out:
1657	return dquot_quota_off(sb, type);
1658}
1659
1660#endif
1661
1662static const struct fs_context_operations ext2_context_ops = {
1663	.parse_param	= ext2_parse_param,
1664	.get_tree	= ext2_get_tree,
1665	.reconfigure	= ext2_reconfigure,
1666	.free		= ext2_free_fc,
1667};
1668
1669static int ext2_init_fs_context(struct fs_context *fc)
1670{
1671	struct ext2_fs_context *ctx;
1672
1673	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1674	if (!ctx)
1675		return -ENOMEM;
1676
1677	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
1678		struct super_block *sb = fc->root->d_sb;
1679		struct ext2_sb_info *sbi = EXT2_SB(sb);
1680
1681		spin_lock(&sbi->s_lock);
1682		ctx->vals_s_mount_opt = sbi->s_mount_opt;
1683		ctx->vals_s_flags = sb->s_flags;
1684		ctx->s_resuid = sbi->s_resuid;
1685		ctx->s_resgid = sbi->s_resgid;
1686		spin_unlock(&sbi->s_lock);
1687	} else {
1688		ctx->s_sb_block = 1;
1689		ctx_set_mount_opt(ctx, EXT2_MOUNT_RESERVATION);
1690	}
1691
1692	fc->fs_private = ctx;
1693	fc->ops = &ext2_context_ops;
1694
1695	return 0;
1696}
1697
1698static struct file_system_type ext2_fs_type = {
1699	.owner		= THIS_MODULE,
1700	.name		= "ext2",
1701	.kill_sb	= kill_block_super,
1702	.fs_flags	= FS_REQUIRES_DEV,
1703	.init_fs_context = ext2_init_fs_context,
1704	.parameters	= ext2_param_spec,
1705};
1706MODULE_ALIAS_FS("ext2");
1707
1708static int __init init_ext2_fs(void)
1709{
1710	int err;
1711
1712	err = init_inodecache();
1713	if (err)
1714		return err;
1715	err = register_filesystem(&ext2_fs_type);
1716	if (err)
1717		goto out;
1718	return 0;
1719out:
1720	destroy_inodecache();
1721	return err;
1722}
1723
1724static void __exit exit_ext2_fs(void)
1725{
1726	unregister_filesystem(&ext2_fs_type);
1727	destroy_inodecache();
1728}
1729
1730MODULE_AUTHOR("Remy Card and others");
1731MODULE_DESCRIPTION("Second Extended Filesystem");
1732MODULE_LICENSE("GPL");
1733module_init(init_ext2_fs)
1734module_exit(exit_ext2_fs)