// SPDX-License-Identifier: GPL-2.0
/*
 * fs/f2fs/super.c
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *             http://www.samsung.com/
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/statfs.h>
#include <linux/buffer_head.h>
#include <linux/backing-dev.h>
#include <linux/kthread.h>
#include <linux/parser.h>
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/proc_fs.h>
#include <linux/random.h>
#include <linux/exportfs.h>
#include <linux/blkdev.h>
#include <linux/quotaops.h>
#include <linux/f2fs_fs.h>
#include <linux/sysfs.h>
#include <linux/quota.h>
#include <linux/unicode.h>
#include <linux/part_stat.h>
#include <linux/zstd.h>
#include <linux/lz4.h>

#include "f2fs.h"
#include "node.h"
#include "segment.h"
#include "xattr.h"
#include "gc.h"
#include "iostat.h"

#define CREATE_TRACE_POINTS
#include <trace/events/f2fs.h>

static struct kmem_cache *f2fs_inode_cachep;

#ifdef CONFIG_F2FS_FAULT_INJECTION

const char *f2fs_fault_name[FAULT_MAX] = {
	[FAULT_KMALLOC]		= "kmalloc",
	[FAULT_KVMALLOC]	= "kvmalloc",
	[FAULT_PAGE_ALLOC]	= "page alloc",
	[FAULT_PAGE_GET]	= "page get",
	[FAULT_ALLOC_NID]	= "alloc nid",
	[FAULT_ORPHAN]		= "orphan",
	[FAULT_BLOCK]		= "no more block",
	[FAULT_DIR_DEPTH]	= "too big dir depth",
	[FAULT_EVICT_INODE]	= "evict_inode fail",
	[FAULT_TRUNCATE]	= "truncate fail",
	[FAULT_READ_IO]		= "read IO error",
	[FAULT_CHECKPOINT]	= "checkpoint error",
	[FAULT_DISCARD]		= "discard error",
	[FAULT_WRITE_IO]	= "write IO error",
	[FAULT_SLAB_ALLOC]	= "slab alloc",
	[FAULT_DQUOT_INIT]	= "dquot initialize",
};

void f2fs_build_fault_attr(struct f2fs_sb_info *sbi, unsigned int rate,
							unsigned int type)
{
	struct f2fs_fault_info *ffi = &F2FS_OPTION(sbi).fault_info;

	if (rate) {
		atomic_set(&ffi->inject_ops, 0);
		ffi->inject_rate = rate;
	}

	if (type)
		ffi->inject_type = type;

	if (!rate && !type)
		memset(ffi, 0, sizeof(struct f2fs_fault_info));
}
#endif

/* f2fs-wide shrinker description */
static struct shrinker f2fs_shrinker_info = {
	.scan_objects = f2fs_shrink_scan,
	.count_objects = f2fs_shrink_count,
	.seeks = DEFAULT_SEEKS,
};

enum {
	Opt_gc_background,
	Opt_disable_roll_forward,
	Opt_norecovery,
	Opt_discard,
	Opt_nodiscard,
	Opt_noheap,
	Opt_heap,
	Opt_user_xattr,
	Opt_nouser_xattr,
	Opt_acl,
	Opt_noacl,
	Opt_active_logs,
	Opt_disable_ext_identify,
	Opt_inline_xattr,
	Opt_noinline_xattr,
	Opt_inline_xattr_size,
	Opt_inline_data,
	Opt_inline_dentry,
	Opt_noinline_dentry,
	Opt_flush_merge,
	Opt_noflush_merge,
	Opt_nobarrier,
	Opt_fastboot,
	Opt_extent_cache,
	Opt_noextent_cache,
	Opt_noinline_data,
	Opt_data_flush,
	Opt_reserve_root,
	Opt_resgid,
	Opt_resuid,
	Opt_mode,
	Opt_io_size_bits,
	Opt_fault_injection,
	Opt_fault_type,
	Opt_lazytime,
	Opt_nolazytime,
	Opt_quota,
	Opt_noquota,
	Opt_usrquota,
	Opt_grpquota,
	Opt_prjquota,
	Opt_usrjquota,
	Opt_grpjquota,
	Opt_prjjquota,
	Opt_offusrjquota,
	Opt_offgrpjquota,
	Opt_offprjjquota,
	Opt_jqfmt_vfsold,
	Opt_jqfmt_vfsv0,
	Opt_jqfmt_vfsv1,
	Opt_whint,
	Opt_alloc,
	Opt_fsync,
	Opt_test_dummy_encryption,
	Opt_inlinecrypt,
	Opt_checkpoint_disable,
	Opt_checkpoint_disable_cap,
	Opt_checkpoint_disable_cap_perc,
	Opt_checkpoint_enable,
	Opt_checkpoint_merge,
	Opt_nocheckpoint_merge,
	Opt_compress_algorithm,
	Opt_compress_log_size,
	Opt_compress_extension,
	Opt_nocompress_extension,
	Opt_compress_chksum,
	Opt_compress_mode,
	Opt_compress_cache,
	Opt_atgc,
	Opt_gc_merge,
	Opt_nogc_merge,
	Opt_discard_unit,
	Opt_err,
};

static match_table_t f2fs_tokens = {
	{Opt_gc_background, "background_gc=%s"},
	{Opt_disable_roll_forward, "disable_roll_forward"},
	{Opt_norecovery, "norecovery"},
	{Opt_discard, "discard"},
	{Opt_nodiscard, "nodiscard"},
	{Opt_noheap, "no_heap"},
	{Opt_heap, "heap"},
	{Opt_user_xattr, "user_xattr"},
	{Opt_nouser_xattr, "nouser_xattr"},
	{Opt_acl, "acl"},
	{Opt_noacl, "noacl"},
	{Opt_active_logs, "active_logs=%u"},
	{Opt_disable_ext_identify, "disable_ext_identify"},
	{Opt_inline_xattr, "inline_xattr"},
	{Opt_noinline_xattr, "noinline_xattr"},
	{Opt_inline_xattr_size, "inline_xattr_size=%u"},
	{Opt_inline_data, "inline_data"},
	{Opt_inline_dentry, "inline_dentry"},
	{Opt_noinline_dentry, "noinline_dentry"},
	{Opt_flush_merge, "flush_merge"},
	{Opt_noflush_merge, "noflush_merge"},
	{Opt_nobarrier, "nobarrier"},
	{Opt_fastboot, "fastboot"},
	{Opt_extent_cache, "extent_cache"},
	{Opt_noextent_cache, "noextent_cache"},
	{Opt_noinline_data, "noinline_data"},
	{Opt_data_flush, "data_flush"},
	{Opt_reserve_root, "reserve_root=%u"},
	{Opt_resgid, "resgid=%u"},
	{Opt_resuid, "resuid=%u"},
	{Opt_mode, "mode=%s"},
	{Opt_io_size_bits, "io_bits=%u"},
	{Opt_fault_injection, "fault_injection=%u"},
	{Opt_fault_type, "fault_type=%u"},
	{Opt_lazytime, "lazytime"},
	{Opt_nolazytime, "nolazytime"},
	{Opt_quota, "quota"},
	{Opt_noquota, "noquota"},
	{Opt_usrquota, "usrquota"},
	{Opt_grpquota, "grpquota"},
	{Opt_prjquota, "prjquota"},
	{Opt_usrjquota, "usrjquota=%s"},
	{Opt_grpjquota, "grpjquota=%s"},
	{Opt_prjjquota, "prjjquota=%s"},
	{Opt_offusrjquota, "usrjquota="},
	{Opt_offgrpjquota, "grpjquota="},
	{Opt_offprjjquota, "prjjquota="},
	{Opt_jqfmt_vfsold, "jqfmt=vfsold"},
	{Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
	{Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
	{Opt_whint, "whint_mode=%s"},
	{Opt_alloc, "alloc_mode=%s"},
	{Opt_fsync, "fsync_mode=%s"},
	{Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
	{Opt_test_dummy_encryption, "test_dummy_encryption"},
	{Opt_inlinecrypt, "inlinecrypt"},
	{Opt_checkpoint_disable, "checkpoint=disable"},
	{Opt_checkpoint_disable_cap, "checkpoint=disable:%u"},
	{Opt_checkpoint_disable_cap_perc, "checkpoint=disable:%u%%"},
	{Opt_checkpoint_enable, "checkpoint=enable"},
	{Opt_checkpoint_merge, "checkpoint_merge"},
	{Opt_nocheckpoint_merge, "nocheckpoint_merge"},
	{Opt_compress_algorithm, "compress_algorithm=%s"},
	{Opt_compress_log_size, "compress_log_size=%u"},
	{Opt_compress_extension, "compress_extension=%s"},
	{Opt_nocompress_extension, "nocompress_extension=%s"},
	{Opt_compress_chksum, "compress_chksum"},
	{Opt_compress_mode, "compress_mode=%s"},
	{Opt_compress_cache, "compress_cache"},
	{Opt_atgc, "atgc"},
	{Opt_gc_merge, "gc_merge"},
	{Opt_nogc_merge, "nogc_merge"},
	{Opt_discard_unit, "discard_unit=%s"},
	{Opt_err, NULL},
};

void f2fs_printk(struct f2fs_sb_info *sbi, const char *fmt, ...)
{
	struct va_format vaf;
	va_list args;
	int level;

	va_start(args, fmt);

	level = printk_get_level(fmt);
	vaf.fmt = printk_skip_level(fmt);
	vaf.va = &args;
	printk("%c%cF2FS-fs (%s): %pV\n",
	       KERN_SOH_ASCII, level, sbi->sb->s_id, &vaf);

	va_end(args);
}

#ifdef CONFIG_UNICODE
static const struct f2fs_sb_encodings {
	__u16 magic;
	char *name;
	char *version;
} f2fs_sb_encoding_map[] = {
	{F2FS_ENC_UTF8_12_1, "utf8", "12.1.0"},
};

static int f2fs_sb_read_encoding(const struct f2fs_super_block *sb,
				 const struct f2fs_sb_encodings **encoding,
				 __u16 *flags)
{
	__u16 magic = le16_to_cpu(sb->s_encoding);
	int i;

	for (i = 0; i < ARRAY_SIZE(f2fs_sb_encoding_map); i++)
		if (magic == f2fs_sb_encoding_map[i].magic)
			break;

	if (i >= ARRAY_SIZE(f2fs_sb_encoding_map))
		return -EINVAL;

	*encoding = &f2fs_sb_encoding_map[i];
	*flags = le16_to_cpu(sb->s_encoding_flags);

	return 0;
}

struct kmem_cache *f2fs_cf_name_slab;
static int __init f2fs_create_casefold_cache(void)
{
	f2fs_cf_name_slab = f2fs_kmem_cache_create("f2fs_casefolded_name",
							F2FS_NAME_LEN);
	if (!f2fs_cf_name_slab)
		return -ENOMEM;
	return 0;
}

static void f2fs_destroy_casefold_cache(void)
{
	kmem_cache_destroy(f2fs_cf_name_slab);
}
#else
static int __init f2fs_create_casefold_cache(void) { return 0; }
static void f2fs_destroy_casefold_cache(void) { }
#endif

static inline void limit_reserve_root(struct f2fs_sb_info *sbi)
{
	block_t limit = min((sbi->user_block_count >> 3),
			sbi->user_block_count - sbi->reserved_blocks);

	/* limit is 12.5% */
	if (test_opt(sbi, RESERVE_ROOT) &&
			F2FS_OPTION(sbi).root_reserved_blocks > limit) {
		F2FS_OPTION(sbi).root_reserved_blocks = limit;
		f2fs_info(sbi, "Reduce reserved blocks for root = %u",
			  F2FS_OPTION(sbi).root_reserved_blocks);
	}
	if (!test_opt(sbi, RESERVE_ROOT) &&
		(!uid_eq(F2FS_OPTION(sbi).s_resuid,
				make_kuid(&init_user_ns, F2FS_DEF_RESUID)) ||
		!gid_eq(F2FS_OPTION(sbi).s_resgid,
				make_kgid(&init_user_ns, F2FS_DEF_RESGID))))
		f2fs_info(sbi, "Ignore s_resuid=%u, s_resgid=%u w/o reserve_root",
			  from_kuid_munged(&init_user_ns,
					   F2FS_OPTION(sbi).s_resuid),
			  from_kgid_munged(&init_user_ns,
					   F2FS_OPTION(sbi).s_resgid));
}

static inline int adjust_reserved_segment(struct f2fs_sb_info *sbi)
{
	unsigned int sec_blks = sbi->blocks_per_seg * sbi->segs_per_sec;
	unsigned int avg_vblocks;
	unsigned int wanted_reserved_segments;
	block_t avail_user_block_count;

	if (!F2FS_IO_ALIGNED(sbi))
		return 0;

	/* average valid block count in section in worst case */
	avg_vblocks = sec_blks / F2FS_IO_SIZE(sbi);

	/*
	 * we need enough free space when migrating one section in worst case
	 */
	wanted_reserved_segments = (F2FS_IO_SIZE(sbi) / avg_vblocks) *
						reserved_segments(sbi);
	wanted_reserved_segments -= reserved_segments(sbi);

	avail_user_block_count = sbi->user_block_count -
				sbi->current_reserved_blocks -
				F2FS_OPTION(sbi).root_reserved_blocks;

	if (wanted_reserved_segments * sbi->blocks_per_seg >
					avail_user_block_count) {
		f2fs_err(sbi, "IO align feature can't grab additional reserved segment: %u, available segments: %u",
			wanted_reserved_segments,
			avail_user_block_count >> sbi->log_blocks_per_seg);
		return -ENOSPC;
	}

	SM_I(sbi)->additional_reserved_segments = wanted_reserved_segments;

	f2fs_info(sbi, "IO align feature needs additional reserved segment: %u",
			 wanted_reserved_segments);

	return 0;
}

static inline void adjust_unusable_cap_perc(struct f2fs_sb_info *sbi)
{
	if (!F2FS_OPTION(sbi).unusable_cap_perc)
		return;

	if (F2FS_OPTION(sbi).unusable_cap_perc == 100)
		F2FS_OPTION(sbi).unusable_cap = sbi->user_block_count;
	else
		F2FS_OPTION(sbi).unusable_cap = (sbi->user_block_count / 100) *
					F2FS_OPTION(sbi).unusable_cap_perc;

	f2fs_info(sbi, "Adjust unusable cap for checkpoint=disable = %u / %u%%",
			F2FS_OPTION(sbi).unusable_cap,
			F2FS_OPTION(sbi).unusable_cap_perc);
}

static void init_once(void *foo)
{
	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;

	inode_init_once(&fi->vfs_inode);
}

#ifdef CONFIG_QUOTA
static const char * const quotatypes[] = INITQFNAMES;
#define QTYPE2NAME(t) (quotatypes[t])
static int f2fs_set_qf_name(struct super_block *sb, int qtype,
							substring_t *args)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	char *qname;
	int ret = -EINVAL;

	if (sb_any_quota_loaded(sb) && !F2FS_OPTION(sbi).s_qf_names[qtype]) {
		f2fs_err(sbi, "Cannot change journaled quota options when quota turned on");
		return -EINVAL;
	}
	if (f2fs_sb_has_quota_ino(sbi)) {
		f2fs_info(sbi, "QUOTA feature is enabled, so ignore qf_name");
		return 0;
	}

	qname = match_strdup(args);
	if (!qname) {
		f2fs_err(sbi, "Not enough memory for storing quotafile name");
		return -ENOMEM;
	}
	if (F2FS_OPTION(sbi).s_qf_names[qtype]) {
		if (strcmp(F2FS_OPTION(sbi).s_qf_names[qtype], qname) == 0)
			ret = 0;
		else
			f2fs_err(sbi, "%s quota file already specified",
				 QTYPE2NAME(qtype));
		goto errout;
	}
	if (strchr(qname, '/')) {
		f2fs_err(sbi, "quotafile must be on filesystem root");
		goto errout;
	}
	F2FS_OPTION(sbi).s_qf_names[qtype] = qname;
	set_opt(sbi, QUOTA);
	return 0;
errout:
	kfree(qname);
	return ret;
}

static int f2fs_clear_qf_name(struct super_block *sb, int qtype)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);

	if (sb_any_quota_loaded(sb) && F2FS_OPTION(sbi).s_qf_names[qtype]) {
		f2fs_err(sbi, "Cannot change journaled quota options when quota turned on");
		return -EINVAL;
	}
	kfree(F2FS_OPTION(sbi).s_qf_names[qtype]);
	F2FS_OPTION(sbi).s_qf_names[qtype] = NULL;
	return 0;
}

static int f2fs_check_quota_options(struct f2fs_sb_info *sbi)
{
	/*
	 * We do the test below only for project quotas. 'usrquota' and
	 * 'grpquota' mount options are allowed even without quota feature
	 * to support legacy quotas in quota files.
	 */
	if (test_opt(sbi, PRJQUOTA) && !f2fs_sb_has_project_quota(sbi)) {
		f2fs_err(sbi, "Project quota feature not enabled. Cannot enable project quota enforcement.");
		return -1;
	}
	if (F2FS_OPTION(sbi).s_qf_names[USRQUOTA] ||
			F2FS_OPTION(sbi).s_qf_names[GRPQUOTA] ||
			F2FS_OPTION(sbi).s_qf_names[PRJQUOTA]) {
		if (test_opt(sbi, USRQUOTA) &&
				F2FS_OPTION(sbi).s_qf_names[USRQUOTA])
			clear_opt(sbi, USRQUOTA);

		if (test_opt(sbi, GRPQUOTA) &&
				F2FS_OPTION(sbi).s_qf_names[GRPQUOTA])
			clear_opt(sbi, GRPQUOTA);

		if (test_opt(sbi, PRJQUOTA) &&
				F2FS_OPTION(sbi).s_qf_names[PRJQUOTA])
			clear_opt(sbi, PRJQUOTA);

		if (test_opt(sbi, GRPQUOTA) || test_opt(sbi, USRQUOTA) ||
				test_opt(sbi, PRJQUOTA)) {
			f2fs_err(sbi, "old and new quota format mixing");
			return -1;
		}

		if (!F2FS_OPTION(sbi).s_jquota_fmt) {
			f2fs_err(sbi, "journaled quota format not specified");
			return -1;
		}
	}

	if (f2fs_sb_has_quota_ino(sbi) && F2FS_OPTION(sbi).s_jquota_fmt) {
		f2fs_info(sbi, "QUOTA feature is enabled, so ignore jquota_fmt");
		F2FS_OPTION(sbi).s_jquota_fmt = 0;
	}
	return 0;
}
#endif

static int f2fs_set_test_dummy_encryption(struct super_block *sb,
					  const char *opt,
					  const substring_t *arg,
					  bool is_remount)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
#ifdef CONFIG_FS_ENCRYPTION
	int err;

	if (!f2fs_sb_has_encrypt(sbi)) {
		f2fs_err(sbi, "Encrypt feature is off");
		return -EINVAL;
	}

	/*
	 * This mount option is just for testing, and it's not worthwhile to
	 * implement the extra complexity (e.g. RCU protection) that would be
	 * needed to allow it to be set or changed during remount.  We do allow
	 * it to be specified during remount, but only if there is no change.
	 */
	if (is_remount && !F2FS_OPTION(sbi).dummy_enc_policy.policy) {
		f2fs_warn(sbi, "Can't set test_dummy_encryption on remount");
		return -EINVAL;
	}
	err = fscrypt_set_test_dummy_encryption(
		sb, arg->from, &F2FS_OPTION(sbi).dummy_enc_policy);
	if (err) {
		if (err == -EEXIST)
			f2fs_warn(sbi,
				  "Can't change test_dummy_encryption on remount");
		else if (err == -EINVAL)
			f2fs_warn(sbi, "Value of option \"%s\" is unrecognized",
				  opt);
		else
			f2fs_warn(sbi, "Error processing option \"%s\" [%d]",
				  opt, err);
		return -EINVAL;
	}
	f2fs_warn(sbi, "Test dummy encryption mode enabled");
#else
	f2fs_warn(sbi, "Test dummy encryption mount option ignored");
#endif
	return 0;
}

#ifdef CONFIG_F2FS_FS_COMPRESSION
static bool is_compress_extension_exist(struct f2fs_sb_info *sbi,
					const char *new_ext, bool is_ext)
{
	unsigned char (*ext)[F2FS_EXTENSION_LEN];
	int ext_cnt;
	int i;

	if (is_ext) {
		ext = F2FS_OPTION(sbi).extensions;
		ext_cnt = F2FS_OPTION(sbi).compress_ext_cnt;
	} else {
		ext = F2FS_OPTION(sbi).noextensions;
		ext_cnt = F2FS_OPTION(sbi).nocompress_ext_cnt;
	}

	for (i = 0; i < ext_cnt; i++) {
		if (!strcasecmp(new_ext, ext[i]))
			return true;
	}

	return false;
}

/*
 * 1. The same extension name cannot not appear in both compress and non-compress extension
 * at the same time.
 * 2. If the compress extension specifies all files, the types specified by the non-compress
 * extension will be treated as special cases and will not be compressed.
 * 3. Don't allow the non-compress extension specifies all files.
 */
static int f2fs_test_compress_extension(struct f2fs_sb_info *sbi)
{
	unsigned char (*ext)[F2FS_EXTENSION_LEN];
	unsigned char (*noext)[F2FS_EXTENSION_LEN];
	int ext_cnt, noext_cnt, index = 0, no_index = 0;

	ext = F2FS_OPTION(sbi).extensions;
	ext_cnt = F2FS_OPTION(sbi).compress_ext_cnt;
	noext = F2FS_OPTION(sbi).noextensions;
	noext_cnt = F2FS_OPTION(sbi).nocompress_ext_cnt;

	if (!noext_cnt)
		return 0;

	for (no_index = 0; no_index < noext_cnt; no_index++) {
		if (!strcasecmp("*", noext[no_index])) {
			f2fs_info(sbi, "Don't allow the nocompress extension specifies all files");
			return -EINVAL;
		}
		for (index = 0; index < ext_cnt; index++) {
			if (!strcasecmp(ext[index], noext[no_index])) {
				f2fs_info(sbi, "Don't allow the same extension %s appear in both compress and nocompress extension",
						ext[index]);
				return -EINVAL;
			}
		}
	}
	return 0;
}

#ifdef CONFIG_F2FS_FS_LZ4
static int f2fs_set_lz4hc_level(struct f2fs_sb_info *sbi, const char *str)
{
#ifdef CONFIG_F2FS_FS_LZ4HC
	unsigned int level;
#endif

	if (strlen(str) == 3) {
		F2FS_OPTION(sbi).compress_level = 0;
		return 0;
	}

#ifdef CONFIG_F2FS_FS_LZ4HC
	str += 3;

	if (str[0] != ':') {
		f2fs_info(sbi, "wrong format, e.g. <alg_name>:<compr_level>");
		return -EINVAL;
	}
	if (kstrtouint(str + 1, 10, &level))
		return -EINVAL;

	if (level < LZ4HC_MIN_CLEVEL || level > LZ4HC_MAX_CLEVEL) {
		f2fs_info(sbi, "invalid lz4hc compress level: %d", level);
		return -EINVAL;
	}

	F2FS_OPTION(sbi).compress_level = level;
	return 0;
#else
	f2fs_info(sbi, "kernel doesn't support lz4hc compression");
	return -EINVAL;
#endif
}
#endif

#ifdef CONFIG_F2FS_FS_ZSTD
static int f2fs_set_zstd_level(struct f2fs_sb_info *sbi, const char *str)
{
	unsigned int level;
	int len = 4;

	if (strlen(str) == len) {
		F2FS_OPTION(sbi).compress_level = 0;
		return 0;
	}

	str += len;

	if (str[0] != ':') {
		f2fs_info(sbi, "wrong format, e.g. <alg_name>:<compr_level>");
		return -EINVAL;
	}
	if (kstrtouint(str + 1, 10, &level))
		return -EINVAL;

	if (!level || level > ZSTD_maxCLevel()) {
		f2fs_info(sbi, "invalid zstd compress level: %d", level);
		return -EINVAL;
	}

	F2FS_OPTION(sbi).compress_level = level;
	return 0;
}
#endif
#endif

static int parse_options(struct super_block *sb, char *options, bool is_remount)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	substring_t args[MAX_OPT_ARGS];
#ifdef CONFIG_F2FS_FS_COMPRESSION
	unsigned char (*ext)[F2FS_EXTENSION_LEN];
	unsigned char (*noext)[F2FS_EXTENSION_LEN];
	int ext_cnt, noext_cnt;
#endif
	char *p, *name;
	int arg = 0;
	kuid_t uid;
	kgid_t gid;
	int ret;

	if (!options)
		goto default_check;

	while ((p = strsep(&options, ",")) != NULL) {
		int token;

		if (!*p)
			continue;
		/*
		 * Initialize args struct so we know whether arg was
		 * found; some options take optional arguments.
		 */
		args[0].to = args[0].from = NULL;
		token = match_token(p, f2fs_tokens, args);

		switch (token) {
		case Opt_gc_background:
			name = match_strdup(&args[0]);

			if (!name)
				return -ENOMEM;
			if (!strcmp(name, "on")) {
				F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_ON;
			} else if (!strcmp(name, "off")) {
				F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_OFF;
			} else if (!strcmp(name, "sync")) {
				F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_SYNC;
			} else {
				kfree(name);
				return -EINVAL;
			}
			kfree(name);
			break;
		case Opt_disable_roll_forward:
			set_opt(sbi, DISABLE_ROLL_FORWARD);
			break;
		case Opt_norecovery:
			/* this option mounts f2fs with ro */
			set_opt(sbi, NORECOVERY);
			if (!f2fs_readonly(sb))
				return -EINVAL;
			break;
		case Opt_discard:
			if (!f2fs_hw_support_discard(sbi)) {
				f2fs_warn(sbi, "device does not support discard");
				break;
			}
			set_opt(sbi, DISCARD);
			break;
		case Opt_nodiscard:
			if (f2fs_hw_should_discard(sbi)) {
				f2fs_warn(sbi, "discard is required for zoned block devices");
				return -EINVAL;
			}
			clear_opt(sbi, DISCARD);
			break;
		case Opt_noheap:
			set_opt(sbi, NOHEAP);
			break;
		case Opt_heap:
			clear_opt(sbi, NOHEAP);
			break;
#ifdef CONFIG_F2FS_FS_XATTR
		case Opt_user_xattr:
			set_opt(sbi, XATTR_USER);
			break;
		case Opt_nouser_xattr:
			clear_opt(sbi, XATTR_USER);
			break;
		case Opt_inline_xattr:
			set_opt(sbi, INLINE_XATTR);
			break;
		case Opt_noinline_xattr:
			clear_opt(sbi, INLINE_XATTR);
			break;
		case Opt_inline_xattr_size:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			set_opt(sbi, INLINE_XATTR_SIZE);
			F2FS_OPTION(sbi).inline_xattr_size = arg;
			break;
#else
		case Opt_user_xattr:
			f2fs_info(sbi, "user_xattr options not supported");
			break;
		case Opt_nouser_xattr:
			f2fs_info(sbi, "nouser_xattr options not supported");
			break;
		case Opt_inline_xattr:
			f2fs_info(sbi, "inline_xattr options not supported");
			break;
		case Opt_noinline_xattr:
			f2fs_info(sbi, "noinline_xattr options not supported");
			break;
#endif
#ifdef CONFIG_F2FS_FS_POSIX_ACL
		case Opt_acl:
			set_opt(sbi, POSIX_ACL);
			break;
		case Opt_noacl:
			clear_opt(sbi, POSIX_ACL);
			break;
#else
		case Opt_acl:
			f2fs_info(sbi, "acl options not supported");
			break;
		case Opt_noacl:
			f2fs_info(sbi, "noacl options not supported");
			break;
#endif
		case Opt_active_logs:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			if (arg != 2 && arg != 4 &&
				arg != NR_CURSEG_PERSIST_TYPE)
				return -EINVAL;
			F2FS_OPTION(sbi).active_logs = arg;
			break;
		case Opt_disable_ext_identify:
			set_opt(sbi, DISABLE_EXT_IDENTIFY);
			break;
		case Opt_inline_data:
			set_opt(sbi, INLINE_DATA);
			break;
		case Opt_inline_dentry:
			set_opt(sbi, INLINE_DENTRY);
			break;
		case Opt_noinline_dentry:
			clear_opt(sbi, INLINE_DENTRY);
			break;
		case Opt_flush_merge:
			set_opt(sbi, FLUSH_MERGE);
			break;
		case Opt_noflush_merge:
			clear_opt(sbi, FLUSH_MERGE);
			break;
		case Opt_nobarrier:
			set_opt(sbi, NOBARRIER);
			break;
		case Opt_fastboot:
			set_opt(sbi, FASTBOOT);
			break;
		case Opt_extent_cache:
			set_opt(sbi, EXTENT_CACHE);
			break;
		case Opt_noextent_cache:
			clear_opt(sbi, EXTENT_CACHE);
			break;
		case Opt_noinline_data:
			clear_opt(sbi, INLINE_DATA);
			break;
		case Opt_data_flush:
			set_opt(sbi, DATA_FLUSH);
			break;
		case Opt_reserve_root:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			if (test_opt(sbi, RESERVE_ROOT)) {
				f2fs_info(sbi, "Preserve previous reserve_root=%u",
					  F2FS_OPTION(sbi).root_reserved_blocks);
			} else {
				F2FS_OPTION(sbi).root_reserved_blocks = arg;
				set_opt(sbi, RESERVE_ROOT);
			}
			break;
		case Opt_resuid:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			uid = make_kuid(current_user_ns(), arg);
			if (!uid_valid(uid)) {
				f2fs_err(sbi, "Invalid uid value %d", arg);
				return -EINVAL;
			}
			F2FS_OPTION(sbi).s_resuid = uid;
			break;
		case Opt_resgid:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			gid = make_kgid(current_user_ns(), arg);
			if (!gid_valid(gid)) {
				f2fs_err(sbi, "Invalid gid value %d", arg);
				return -EINVAL;
			}
			F2FS_OPTION(sbi).s_resgid = gid;
			break;
		case Opt_mode:
			name = match_strdup(&args[0]);

			if (!name)
				return -ENOMEM;
			if (!strcmp(name, "adaptive")) {
				if (f2fs_sb_has_blkzoned(sbi)) {
					f2fs_warn(sbi, "adaptive mode is not allowed with zoned block device feature");
					kfree(name);
					return -EINVAL;
				}
				F2FS_OPTION(sbi).fs_mode = FS_MODE_ADAPTIVE;
			} else if (!strcmp(name, "lfs")) {
				F2FS_OPTION(sbi).fs_mode = FS_MODE_LFS;
			} else {
				kfree(name);
				return -EINVAL;
			}
			kfree(name);
			break;
		case Opt_io_size_bits:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			if (arg <= 0 || arg > __ilog2_u32(BIO_MAX_VECS)) {
				f2fs_warn(sbi, "Not support %d, larger than %d",
					  1 << arg, BIO_MAX_VECS);
				return -EINVAL;
			}
			F2FS_OPTION(sbi).write_io_size_bits = arg;
			break;
#ifdef CONFIG_F2FS_FAULT_INJECTION
		case Opt_fault_injection:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			f2fs_build_fault_attr(sbi, arg, F2FS_ALL_FAULT_TYPE);
			set_opt(sbi, FAULT_INJECTION);
			break;

		case Opt_fault_type:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			f2fs_build_fault_attr(sbi, 0, arg);
			set_opt(sbi, FAULT_INJECTION);
			break;
#else
		case Opt_fault_injection:
			f2fs_info(sbi, "fault_injection options not supported");
			break;

		case Opt_fault_type:
			f2fs_info(sbi, "fault_type options not supported");
			break;
#endif
		case Opt_lazytime:
			sb->s_flags |= SB_LAZYTIME;
			break;
		case Opt_nolazytime:
			sb->s_flags &= ~SB_LAZYTIME;
			break;
#ifdef CONFIG_QUOTA
		case Opt_quota:
		case Opt_usrquota:
			set_opt(sbi, USRQUOTA);
			break;
		case Opt_grpquota:
			set_opt(sbi, GRPQUOTA);
			break;
		case Opt_prjquota:
			set_opt(sbi, PRJQUOTA);
			break;
		case Opt_usrjquota:
			ret = f2fs_set_qf_name(sb, USRQUOTA, &args[0]);
			if (ret)
				return ret;
			break;
		case Opt_grpjquota:
			ret = f2fs_set_qf_name(sb, GRPQUOTA, &args[0]);
			if (ret)
				return ret;
			break;
		case Opt_prjjquota:
			ret = f2fs_set_qf_name(sb, PRJQUOTA, &args[0]);
			if (ret)
				return ret;
			break;
		case Opt_offusrjquota:
			ret = f2fs_clear_qf_name(sb, USRQUOTA);
			if (ret)
				return ret;
			break;
		case Opt_offgrpjquota:
			ret = f2fs_clear_qf_name(sb, GRPQUOTA);
			if (ret)
				return ret;
			break;
		case Opt_offprjjquota:
			ret = f2fs_clear_qf_name(sb, PRJQUOTA);
			if (ret)
				return ret;
			break;
		case Opt_jqfmt_vfsold:
			F2FS_OPTION(sbi).s_jquota_fmt = QFMT_VFS_OLD;
			break;
		case Opt_jqfmt_vfsv0:
			F2FS_OPTION(sbi).s_jquota_fmt = QFMT_VFS_V0;
			break;
		case Opt_jqfmt_vfsv1:
			F2FS_OPTION(sbi).s_jquota_fmt = QFMT_VFS_V1;
			break;
		case Opt_noquota:
			clear_opt(sbi, QUOTA);
			clear_opt(sbi, USRQUOTA);
			clear_opt(sbi, GRPQUOTA);
			clear_opt(sbi, PRJQUOTA);
			break;
#else
		case Opt_quota:
		case Opt_usrquota:
		case Opt_grpquota:
		case Opt_prjquota:
		case Opt_usrjquota:
		case Opt_grpjquota:
		case Opt_prjjquota:
		case Opt_offusrjquota:
		case Opt_offgrpjquota:
		case Opt_offprjjquota:
		case Opt_jqfmt_vfsold:
		case Opt_jqfmt_vfsv0:
		case Opt_jqfmt_vfsv1:
		case Opt_noquota:
			f2fs_info(sbi, "quota operations not supported");
			break;
#endif
		case Opt_whint:
			name = match_strdup(&args[0]);
			if (!name)
				return -ENOMEM;
			if (!strcmp(name, "user-based")) {
				F2FS_OPTION(sbi).whint_mode = WHINT_MODE_USER;
			} else if (!strcmp(name, "off")) {
				F2FS_OPTION(sbi).whint_mode = WHINT_MODE_OFF;
			} else if (!strcmp(name, "fs-based")) {
				F2FS_OPTION(sbi).whint_mode = WHINT_MODE_FS;
			} else {
				kfree(name);
				return -EINVAL;
			}
			kfree(name);
			break;
		case Opt_alloc:
			name = match_strdup(&args[0]);
			if (!name)
				return -ENOMEM;

			if (!strcmp(name, "default")) {
				F2FS_OPTION(sbi).alloc_mode = ALLOC_MODE_DEFAULT;
			} else if (!strcmp(name, "reuse")) {
				F2FS_OPTION(sbi).alloc_mode = ALLOC_MODE_REUSE;
			} else {
				kfree(name);
				return -EINVAL;
			}
			kfree(name);
			break;
		case Opt_fsync:
			name = match_strdup(&args[0]);
			if (!name)
				return -ENOMEM;
			if (!strcmp(name, "posix")) {
				F2FS_OPTION(sbi).fsync_mode = FSYNC_MODE_POSIX;
			} else if (!strcmp(name, "strict")) {
				F2FS_OPTION(sbi).fsync_mode = FSYNC_MODE_STRICT;
			} else if (!strcmp(name, "nobarrier")) {
				F2FS_OPTION(sbi).fsync_mode =
							FSYNC_MODE_NOBARRIER;
			} else {
				kfree(name);
				return -EINVAL;
			}
			kfree(name);
			break;
		case Opt_test_dummy_encryption:
			ret = f2fs_set_test_dummy_encryption(sb, p, &args[0],
							     is_remount);
			if (ret)
				return ret;
			break;
		case Opt_inlinecrypt:
#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
			sb->s_flags |= SB_INLINECRYPT;
#else
			f2fs_info(sbi, "inline encryption not supported");
#endif
			break;
		case Opt_checkpoint_disable_cap_perc:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			if (arg < 0 || arg > 100)
				return -EINVAL;
			F2FS_OPTION(sbi).unusable_cap_perc = arg;
			set_opt(sbi, DISABLE_CHECKPOINT);
			break;
		case Opt_checkpoint_disable_cap:
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			F2FS_OPTION(sbi).unusable_cap = arg;
			set_opt(sbi, DISABLE_CHECKPOINT);
			break;
		case Opt_checkpoint_disable:
			set_opt(sbi, DISABLE_CHECKPOINT);
			break;
		case Opt_checkpoint_enable:
			clear_opt(sbi, DISABLE_CHECKPOINT);
			break;
		case Opt_checkpoint_merge:
			set_opt(sbi, MERGE_CHECKPOINT);
			break;
		case Opt_nocheckpoint_merge:
			clear_opt(sbi, MERGE_CHECKPOINT);
			break;
#ifdef CONFIG_F2FS_FS_COMPRESSION
		case Opt_compress_algorithm:
			if (!f2fs_sb_has_compression(sbi)) {
				f2fs_info(sbi, "Image doesn't support compression");
				break;
			}
			name = match_strdup(&args[0]);
			if (!name)
				return -ENOMEM;
			if (!strcmp(name, "lzo")) {
#ifdef CONFIG_F2FS_FS_LZO
				F2FS_OPTION(sbi).compress_level = 0;
				F2FS_OPTION(sbi).compress_algorithm =
								COMPRESS_LZO;
#else
				f2fs_info(sbi, "kernel doesn't support lzo compression");
#endif
			} else if (!strncmp(name, "lz4", 3)) {
#ifdef CONFIG_F2FS_FS_LZ4
				ret = f2fs_set_lz4hc_level(sbi, name);
				if (ret) {
					kfree(name);
					return -EINVAL;
				}
				F2FS_OPTION(sbi).compress_algorithm =
								COMPRESS_LZ4;
#else
				f2fs_info(sbi, "kernel doesn't support lz4 compression");
#endif
			} else if (!strncmp(name, "zstd", 4)) {
#ifdef CONFIG_F2FS_FS_ZSTD
				ret = f2fs_set_zstd_level(sbi, name);
				if (ret) {
					kfree(name);
					return -EINVAL;
				}
				F2FS_OPTION(sbi).compress_algorithm =
								COMPRESS_ZSTD;
#else
				f2fs_info(sbi, "kernel doesn't support zstd compression");
#endif
			} else if (!strcmp(name, "lzo-rle")) {
#ifdef CONFIG_F2FS_FS_LZORLE
				F2FS_OPTION(sbi).compress_level = 0;
				F2FS_OPTION(sbi).compress_algorithm =
								COMPRESS_LZORLE;
#else
				f2fs_info(sbi, "kernel doesn't support lzorle compression");
#endif
			} else {
				kfree(name);
				return -EINVAL;
			}
			kfree(name);
			break;
		case Opt_compress_log_size:
			if (!f2fs_sb_has_compression(sbi)) {
				f2fs_info(sbi, "Image doesn't support compression");
				break;
			}
			if (args->from && match_int(args, &arg))
				return -EINVAL;
			if (arg < MIN_COMPRESS_LOG_SIZE ||
				arg > MAX_COMPRESS_LOG_SIZE) {
				f2fs_err(sbi,
					"Compress cluster log size is out of range");
				return -EINVAL;
			}
			F2FS_OPTION(sbi).compress_log_size = arg;
			break;
		case Opt_compress_extension:
			if (!f2fs_sb_has_compression(sbi)) {
				f2fs_info(sbi, "Image doesn't support compression");
				break;
			}
			name = match_strdup(&args[0]);
			if (!name)
				return -ENOMEM;

			ext = F2FS_OPTION(sbi).extensions;
			ext_cnt = F2FS_OPTION(sbi).compress_ext_cnt;

			if (strlen(name) >= F2FS_EXTENSION_LEN ||
				ext_cnt >= COMPRESS_EXT_NUM) {
				f2fs_err(sbi,
					"invalid extension length/number");
				kfree(name);
				return -EINVAL;
			}

			if (is_compress_extension_exist(sbi, name, true)) {
				kfree(name);
				break;
			}

			strcpy(ext[ext_cnt], name);
			F2FS_OPTION(sbi).compress_ext_cnt++;
			kfree(name);
			break;
		case Opt_nocompress_extension:
			if (!f2fs_sb_has_compression(sbi)) {
				f2fs_info(sbi, "Image doesn't support compression");
				break;
			}
			name = match_strdup(&args[0]);
			if (!name)
				return -ENOMEM;

			noext = F2FS_OPTION(sbi).noextensions;
			noext_cnt = F2FS_OPTION(sbi).nocompress_ext_cnt;

			if (strlen(name) >= F2FS_EXTENSION_LEN ||
				noext_cnt >= COMPRESS_EXT_NUM) {
				f2fs_err(sbi,
					"invalid extension length/number");
				kfree(name);
				return -EINVAL;
			}

			if (is_compress_extension_exist(sbi, name, false)) {
				kfree(name);
				break;
			}

			strcpy(noext[noext_cnt], name);
			F2FS_OPTION(sbi).nocompress_ext_cnt++;
			kfree(name);
			break;
		case Opt_compress_chksum:
			F2FS_OPTION(sbi).compress_chksum = true;
			break;
		case Opt_compress_mode:
			name = match_strdup(&args[0]);
			if (!name)
				return -ENOMEM;
			if (!strcmp(name, "fs")) {
				F2FS_OPTION(sbi).compress_mode = COMPR_MODE_FS;
			} else if (!strcmp(name, "user")) {
				F2FS_OPTION(sbi).compress_mode = COMPR_MODE_USER;
			} else {
				kfree(name);
				return -EINVAL;
			}
			kfree(name);
			break;
		case Opt_compress_cache:
			set_opt(sbi, COMPRESS_CACHE);
			break;
#else
		case Opt_compress_algorithm:
		case Opt_compress_log_size:
		case Opt_compress_extension:
		case Opt_nocompress_extension:
		case Opt_compress_chksum:
		case Opt_compress_mode:
		case Opt_compress_cache:
			f2fs_info(sbi, "compression options not supported");
			break;
#endif
		case Opt_atgc:
			set_opt(sbi, ATGC);
			break;
		case Opt_gc_merge:
			set_opt(sbi, GC_MERGE);
			break;
		case Opt_nogc_merge:
			clear_opt(sbi, GC_MERGE);
			break;
		case Opt_discard_unit:
			name = match_strdup(&args[0]);
			if (!name)
				return -ENOMEM;
			if (!strcmp(name, "block")) {
				F2FS_OPTION(sbi).discard_unit =
						DISCARD_UNIT_BLOCK;
			} else if (!strcmp(name, "segment")) {
				F2FS_OPTION(sbi).discard_unit =
						DISCARD_UNIT_SEGMENT;
			} else if (!strcmp(name, "section")) {
				F2FS_OPTION(sbi).discard_unit =
						DISCARD_UNIT_SECTION;
			} else {
				kfree(name);
				return -EINVAL;
			}
			kfree(name);
			break;
		default:
			f2fs_err(sbi, "Unrecognized mount option \"%s\" or missing value",
				 p);
			return -EINVAL;
		}
	}
default_check:
#ifdef CONFIG_QUOTA
	if (f2fs_check_quota_options(sbi))
		return -EINVAL;
#else
	if (f2fs_sb_has_quota_ino(sbi) && !f2fs_readonly(sbi->sb)) {
		f2fs_info(sbi, "Filesystem with quota feature cannot be mounted RDWR without CONFIG_QUOTA");
		return -EINVAL;
	}
	if (f2fs_sb_has_project_quota(sbi) && !f2fs_readonly(sbi->sb)) {
		f2fs_err(sbi, "Filesystem with project quota feature cannot be mounted RDWR without CONFIG_QUOTA");
		return -EINVAL;
	}
#endif
#ifndef CONFIG_UNICODE
	if (f2fs_sb_has_casefold(sbi)) {
		f2fs_err(sbi,
			"Filesystem with casefold feature cannot be mounted without CONFIG_UNICODE");
		return -EINVAL;
	}
#endif
	/*
	 * The BLKZONED feature indicates that the drive was formatted with
	 * zone alignment optimization. This is optional for host-aware
	 * devices, but mandatory for host-managed zoned block devices.
	 */
#ifndef CONFIG_BLK_DEV_ZONED
	if (f2fs_sb_has_blkzoned(sbi)) {
		f2fs_err(sbi, "Zoned block device support is not enabled");
		return -EINVAL;
	}
#endif
	if (f2fs_sb_has_blkzoned(sbi)) {
		if (F2FS_OPTION(sbi).discard_unit !=
						DISCARD_UNIT_SECTION) {
			f2fs_info(sbi, "Zoned block device doesn't need small discard, set discard_unit=section by default");
			F2FS_OPTION(sbi).discard_unit =
					DISCARD_UNIT_SECTION;
		}
	}

#ifdef CONFIG_F2FS_FS_COMPRESSION
	if (f2fs_test_compress_extension(sbi)) {
		f2fs_err(sbi, "invalid compress or nocompress extension");
		return -EINVAL;
	}
#endif

	if (F2FS_IO_SIZE_BITS(sbi) && !f2fs_lfs_mode(sbi)) {
		f2fs_err(sbi, "Should set mode=lfs with %uKB-sized IO",
			 F2FS_IO_SIZE_KB(sbi));
		return -EINVAL;
	}

	if (test_opt(sbi, INLINE_XATTR_SIZE)) {
		int min_size, max_size;

		if (!f2fs_sb_has_extra_attr(sbi) ||
			!f2fs_sb_has_flexible_inline_xattr(sbi)) {
			f2fs_err(sbi, "extra_attr or flexible_inline_xattr feature is off");
			return -EINVAL;
		}
		if (!test_opt(sbi, INLINE_XATTR)) {
			f2fs_err(sbi, "inline_xattr_size option should be set with inline_xattr option");
			return -EINVAL;
		}

		min_size = sizeof(struct f2fs_xattr_header) / sizeof(__le32);
		max_size = MAX_INLINE_XATTR_SIZE;

		if (F2FS_OPTION(sbi).inline_xattr_size < min_size ||
				F2FS_OPTION(sbi).inline_xattr_size > max_size) {
			f2fs_err(sbi, "inline xattr size is out of range: %d ~ %d",
				 min_size, max_size);
			return -EINVAL;
		}
	}

	if (test_opt(sbi, DISABLE_CHECKPOINT) && f2fs_lfs_mode(sbi)) {
		f2fs_err(sbi, "LFS not compatible with checkpoint=disable");
		return -EINVAL;
	}

	/* Not pass down write hints if the number of active logs is lesser
	 * than NR_CURSEG_PERSIST_TYPE.
	 */
	if (F2FS_OPTION(sbi).active_logs != NR_CURSEG_PERSIST_TYPE)
		F2FS_OPTION(sbi).whint_mode = WHINT_MODE_OFF;

	if (f2fs_sb_has_readonly(sbi) && !f2fs_readonly(sbi->sb)) {
		f2fs_err(sbi, "Allow to mount readonly mode only");
		return -EROFS;
	}
	return 0;
}

static struct inode *f2fs_alloc_inode(struct super_block *sb)
{
	struct f2fs_inode_info *fi;

	fi = f2fs_kmem_cache_alloc(f2fs_inode_cachep,
				GFP_F2FS_ZERO, false, F2FS_SB(sb));
	if (!fi)
		return NULL;

	init_once((void *) fi);

	/* Initialize f2fs-specific inode info */
	atomic_set(&fi->dirty_pages, 0);
	atomic_set(&fi->i_compr_blocks, 0);
	init_rwsem(&fi->i_sem);
	spin_lock_init(&fi->i_size_lock);
	INIT_LIST_HEAD(&fi->dirty_list);
	INIT_LIST_HEAD(&fi->gdirty_list);
	INIT_LIST_HEAD(&fi->inmem_ilist);
	INIT_LIST_HEAD(&fi->inmem_pages);
	mutex_init(&fi->inmem_lock);
	init_rwsem(&fi->i_gc_rwsem[READ]);
	init_rwsem(&fi->i_gc_rwsem[WRITE]);
	init_rwsem(&fi->i_xattr_sem);

	/* Will be used by directory only */
	fi->i_dir_level = F2FS_SB(sb)->dir_level;

	return &fi->vfs_inode;
}

static int f2fs_drop_inode(struct inode *inode)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	int ret;

	/*
	 * during filesystem shutdown, if checkpoint is disabled,
	 * drop useless meta/node dirty pages.
	 */
	if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED))) {
		if (inode->i_ino == F2FS_NODE_INO(sbi) ||
			inode->i_ino == F2FS_META_INO(sbi)) {
			trace_f2fs_drop_inode(inode, 1);
			return 1;
		}
	}

	/*
	 * This is to avoid a deadlock condition like below.
	 * writeback_single_inode(inode)
	 *  - f2fs_write_data_page
	 *    - f2fs_gc -> iput -> evict
	 *       - inode_wait_for_writeback(inode)
	 */
	if ((!inode_unhashed(inode) && inode->i_state & I_SYNC)) {
		if (!inode->i_nlink && !is_bad_inode(inode)) {
			/* to avoid evict_inode call simultaneously */
			atomic_inc(&inode->i_count);
			spin_unlock(&inode->i_lock);

			/* some remained atomic pages should discarded */
			if (f2fs_is_atomic_file(inode))
				f2fs_drop_inmem_pages(inode);

			/* should remain fi->extent_tree for writepage */
			f2fs_destroy_extent_node(inode);

			sb_start_intwrite(inode->i_sb);
			f2fs_i_size_write(inode, 0);

			f2fs_submit_merged_write_cond(F2FS_I_SB(inode),
					inode, NULL, 0, DATA);
			truncate_inode_pages_final(inode->i_mapping);

			if (F2FS_HAS_BLOCKS(inode))
				f2fs_truncate(inode);

			sb_end_intwrite(inode->i_sb);

			spin_lock(&inode->i_lock);
			atomic_dec(&inode->i_count);
		}
		trace_f2fs_drop_inode(inode, 0);
		return 0;
	}
	ret = generic_drop_inode(inode);
	if (!ret)
		ret = fscrypt_drop_inode(inode);
	trace_f2fs_drop_inode(inode, ret);
	return ret;
}

int f2fs_inode_dirtied(struct inode *inode, bool sync)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	int ret = 0;

	spin_lock(&sbi->inode_lock[DIRTY_META]);
	if (is_inode_flag_set(inode, FI_DIRTY_INODE)) {
		ret = 1;
	} else {
		set_inode_flag(inode, FI_DIRTY_INODE);
		stat_inc_dirty_inode(sbi, DIRTY_META);
	}
	if (sync && list_empty(&F2FS_I(inode)->gdirty_list)) {
		list_add_tail(&F2FS_I(inode)->gdirty_list,
				&sbi->inode_list[DIRTY_META]);
		inc_page_count(sbi, F2FS_DIRTY_IMETA);
	}
	spin_unlock(&sbi->inode_lock[DIRTY_META]);
	return ret;
}

void f2fs_inode_synced(struct inode *inode)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

	spin_lock(&sbi->inode_lock[DIRTY_META]);
	if (!is_inode_flag_set(inode, FI_DIRTY_INODE)) {
		spin_unlock(&sbi->inode_lock[DIRTY_META]);
		return;
	}
	if (!list_empty(&F2FS_I(inode)->gdirty_list)) {
		list_del_init(&F2FS_I(inode)->gdirty_list);
		dec_page_count(sbi, F2FS_DIRTY_IMETA);
	}
	clear_inode_flag(inode, FI_DIRTY_INODE);
	clear_inode_flag(inode, FI_AUTO_RECOVER);
	stat_dec_dirty_inode(F2FS_I_SB(inode), DIRTY_META);
	spin_unlock(&sbi->inode_lock[DIRTY_META]);
}

/*
 * f2fs_dirty_inode() is called from __mark_inode_dirty()
 *
 * We should call set_dirty_inode to write the dirty inode through write_inode.
 */
static void f2fs_dirty_inode(struct inode *inode, int flags)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

	if (inode->i_ino == F2FS_NODE_INO(sbi) ||
			inode->i_ino == F2FS_META_INO(sbi))
		return;

	if (is_inode_flag_set(inode, FI_AUTO_RECOVER))
		clear_inode_flag(inode, FI_AUTO_RECOVER);

	f2fs_inode_dirtied(inode, false);
}

static void f2fs_free_inode(struct inode *inode)
{
	fscrypt_free_inode(inode);
	kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
}

static void destroy_percpu_info(struct f2fs_sb_info *sbi)
{
	percpu_counter_destroy(&sbi->alloc_valid_block_count);
	percpu_counter_destroy(&sbi->total_valid_inode_count);
}

static void destroy_device_list(struct f2fs_sb_info *sbi)
{
	int i;

	for (i = 0; i < sbi->s_ndevs; i++) {
		blkdev_put(FDEV(i).bdev, FMODE_EXCL);
#ifdef CONFIG_BLK_DEV_ZONED
		kvfree(FDEV(i).blkz_seq);
#endif
	}
	kvfree(sbi->devs);
}

static void f2fs_put_super(struct super_block *sb)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	int i;
	bool dropped;

	/* unregister procfs/sysfs entries in advance to avoid race case */
	f2fs_unregister_sysfs(sbi);

	f2fs_quota_off_umount(sb);

	/* prevent remaining shrinker jobs */
	mutex_lock(&sbi->umount_mutex);

	/*
	 * flush all issued checkpoints and stop checkpoint issue thread.
	 * after then, all checkpoints should be done by each process context.
	 */
	f2fs_stop_ckpt_thread(sbi);

	/*
	 * We don't need to do checkpoint when superblock is clean.
	 * But, the previous checkpoint was not done by umount, it needs to do
	 * clean checkpoint again.
	 */
	if ((is_sbi_flag_set(sbi, SBI_IS_DIRTY) ||
			!is_set_ckpt_flags(sbi, CP_UMOUNT_FLAG))) {
		struct cp_control cpc = {
			.reason = CP_UMOUNT,
		};
		f2fs_write_checkpoint(sbi, &cpc);
	}

	/* be sure to wait for any on-going discard commands */
	dropped = f2fs_issue_discard_timeout(sbi);

	if ((f2fs_hw_support_discard(sbi) || f2fs_hw_should_discard(sbi)) &&
					!sbi->discard_blks && !dropped) {
		struct cp_control cpc = {
			.reason = CP_UMOUNT | CP_TRIMMED,
		};
		f2fs_write_checkpoint(sbi, &cpc);
	}

	/*
	 * normally superblock is clean, so we need to release this.
	 * In addition, EIO will skip do checkpoint, we need this as well.
	 */
	f2fs_release_ino_entry(sbi, true);

	f2fs_leave_shrinker(sbi);
	mutex_unlock(&sbi->umount_mutex);

	/* our cp_error case, we can wait for any writeback page */
	f2fs_flush_merged_writes(sbi);

	f2fs_wait_on_all_pages(sbi, F2FS_WB_CP_DATA);

	f2fs_bug_on(sbi, sbi->fsync_node_num);

	f2fs_destroy_compress_inode(sbi);

	iput(sbi->node_inode);
	sbi->node_inode = NULL;

	iput(sbi->meta_inode);
	sbi->meta_inode = NULL;

	/*
	 * iput() can update stat information, if f2fs_write_checkpoint()
	 * above failed with error.
	 */
	f2fs_destroy_stats(sbi);

	/* destroy f2fs internal modules */
	f2fs_destroy_node_manager(sbi);
	f2fs_destroy_segment_manager(sbi);

	f2fs_destroy_post_read_wq(sbi);

	kvfree(sbi->ckpt);

	sb->s_fs_info = NULL;
	if (sbi->s_chksum_driver)
		crypto_free_shash(sbi->s_chksum_driver);
	kfree(sbi->raw_super);

	destroy_device_list(sbi);
	f2fs_destroy_page_array_cache(sbi);
	f2fs_destroy_xattr_caches(sbi);
	mempool_destroy(sbi->write_io_dummy);
#ifdef CONFIG_QUOTA
	for (i = 0; i < MAXQUOTAS; i++)
		kfree(F2FS_OPTION(sbi).s_qf_names[i]);
#endif
	fscrypt_free_dummy_policy(&F2FS_OPTION(sbi).dummy_enc_policy);
	destroy_percpu_info(sbi);
	f2fs_destroy_iostat(sbi);
	for (i = 0; i < NR_PAGE_TYPE; i++)
		kvfree(sbi->write_io[i]);
#ifdef CONFIG_UNICODE
	utf8_unload(sb->s_encoding);
#endif
	kfree(sbi);
}

int f2fs_sync_fs(struct super_block *sb, int sync)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	int err = 0;

	if (unlikely(f2fs_cp_error(sbi)))
		return 0;
	if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED)))
		return 0;

	trace_f2fs_sync_fs(sb, sync);

	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
		return -EAGAIN;

	if (sync)
		err = f2fs_issue_checkpoint(sbi);

	return err;
}

static int f2fs_freeze(struct super_block *sb)
{
	if (f2fs_readonly(sb))
		return 0;

	/* IO error happened before */
	if (unlikely(f2fs_cp_error(F2FS_SB(sb))))
		return -EIO;

	/* must be clean, since sync_filesystem() was already called */
	if (is_sbi_flag_set(F2FS_SB(sb), SBI_IS_DIRTY))
		return -EINVAL;

	/* Let's flush checkpoints and stop the thread. */
	f2fs_flush_ckpt_thread(F2FS_SB(sb));

	/* to avoid deadlock on f2fs_evict_inode->SB_FREEZE_FS */
	set_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING);
	return 0;
}

static int f2fs_unfreeze(struct super_block *sb)
{
	clear_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING);
	return 0;
}

#ifdef CONFIG_QUOTA
static int f2fs_statfs_project(struct super_block *sb,
				kprojid_t projid, struct kstatfs *buf)
{
	struct kqid qid;
	struct dquot *dquot;
	u64 limit;
	u64 curblock;

	qid = make_kqid_projid(projid);
	dquot = dqget(sb, qid);
	if (IS_ERR(dquot))
		return PTR_ERR(dquot);
	spin_lock(&dquot->dq_dqb_lock);

	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
					dquot->dq_dqb.dqb_bhardlimit);
	if (limit)
		limit >>= sb->s_blocksize_bits;

	if (limit && buf->f_blocks > limit) {
		curblock = (dquot->dq_dqb.dqb_curspace +
			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
		buf->f_blocks = limit;
		buf->f_bfree = buf->f_bavail =
			(buf->f_blocks > curblock) ?
			 (buf->f_blocks - curblock) : 0;
	}

	limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
					dquot->dq_dqb.dqb_ihardlimit);

	if (limit && buf->f_files > limit) {
		buf->f_files = limit;
		buf->f_ffree =
			(buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
			 (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
	}

	spin_unlock(&dquot->dq_dqb_lock);
	dqput(dquot);
	return 0;
}
#endif

static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct super_block *sb = dentry->d_sb;
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
	block_t total_count, user_block_count, start_count;
	u64 avail_node_count;

	total_count = le64_to_cpu(sbi->raw_super->block_count);
	user_block_count = sbi->user_block_count;
	start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
	buf->f_type = F2FS_SUPER_MAGIC;
	buf->f_bsize = sbi->blocksize;

	buf->f_blocks = total_count - start_count;
	buf->f_bfree = user_block_count - valid_user_blocks(sbi) -
						sbi->current_reserved_blocks;

	spin_lock(&sbi->stat_lock);
	if (unlikely(buf->f_bfree <= sbi->unusable_block_count))
		buf->f_bfree = 0;
	else
		buf->f_bfree -= sbi->unusable_block_count;
	spin_unlock(&sbi->stat_lock);

	if (buf->f_bfree > F2FS_OPTION(sbi).root_reserved_blocks)
		buf->f_bavail = buf->f_bfree -
				F2FS_OPTION(sbi).root_reserved_blocks;
	else
		buf->f_bavail = 0;

	avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;

	if (avail_node_count > user_block_count) {
		buf->f_files = user_block_count;
		buf->f_ffree = buf->f_bavail;
	} else {
		buf->f_files = avail_node_count;
		buf->f_ffree = min(avail_node_count - valid_node_count(sbi),
					buf->f_bavail);
	}

	buf->f_namelen = F2FS_NAME_LEN;
	buf->f_fsid    = u64_to_fsid(id);

#ifdef CONFIG_QUOTA
	if (is_inode_flag_set(dentry->d_inode, FI_PROJ_INHERIT) &&
			sb_has_quota_limits_enabled(sb, PRJQUOTA)) {
		f2fs_statfs_project(sb, F2FS_I(dentry->d_inode)->i_projid, buf);
	}
#endif
	return 0;
}

static inline void f2fs_show_quota_options(struct seq_file *seq,
					   struct super_block *sb)
{
#ifdef CONFIG_QUOTA
	struct f2fs_sb_info *sbi = F2FS_SB(sb);

	if (F2FS_OPTION(sbi).s_jquota_fmt) {
		char *fmtname = "";

		switch (F2FS_OPTION(sbi).s_jquota_fmt) {
		case QFMT_VFS_OLD:
			fmtname = "vfsold";
			break;
		case QFMT_VFS_V0:
			fmtname = "vfsv0";
			break;
		case QFMT_VFS_V1:
			fmtname = "vfsv1";
			break;
		}
		seq_printf(seq, ",jqfmt=%s", fmtname);
	}

	if (F2FS_OPTION(sbi).s_qf_names[USRQUOTA])
		seq_show_option(seq, "usrjquota",
			F2FS_OPTION(sbi).s_qf_names[USRQUOTA]);

	if (F2FS_OPTION(sbi).s_qf_names[GRPQUOTA])
		seq_show_option(seq, "grpjquota",
			F2FS_OPTION(sbi).s_qf_names[GRPQUOTA]);

	if (F2FS_OPTION(sbi).s_qf_names[PRJQUOTA])
		seq_show_option(seq, "prjjquota",
			F2FS_OPTION(sbi).s_qf_names[PRJQUOTA]);
#endif
}

#ifdef CONFIG_F2FS_FS_COMPRESSION
static inline void f2fs_show_compress_options(struct seq_file *seq,
							struct super_block *sb)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	char *algtype = "";
	int i;

	if (!f2fs_sb_has_compression(sbi))
		return;

	switch (F2FS_OPTION(sbi).compress_algorithm) {
	case COMPRESS_LZO:
		algtype = "lzo";
		break;
	case COMPRESS_LZ4:
		algtype = "lz4";
		break;
	case COMPRESS_ZSTD:
		algtype = "zstd";
		break;
	case COMPRESS_LZORLE:
		algtype = "lzo-rle";
		break;
	}
	seq_printf(seq, ",compress_algorithm=%s", algtype);

	if (F2FS_OPTION(sbi).compress_level)
		seq_printf(seq, ":%d", F2FS_OPTION(sbi).compress_level);

	seq_printf(seq, ",compress_log_size=%u",
			F2FS_OPTION(sbi).compress_log_size);

	for (i = 0; i < F2FS_OPTION(sbi).compress_ext_cnt; i++) {
		seq_printf(seq, ",compress_extension=%s",
			F2FS_OPTION(sbi).extensions[i]);
	}

	for (i = 0; i < F2FS_OPTION(sbi).nocompress_ext_cnt; i++) {
		seq_printf(seq, ",nocompress_extension=%s",
			F2FS_OPTION(sbi).noextensions[i]);
	}

	if (F2FS_OPTION(sbi).compress_chksum)
		seq_puts(seq, ",compress_chksum");

	if (F2FS_OPTION(sbi).compress_mode == COMPR_MODE_FS)
		seq_printf(seq, ",compress_mode=%s", "fs");
	else if (F2FS_OPTION(sbi).compress_mode == COMPR_MODE_USER)
		seq_printf(seq, ",compress_mode=%s", "user");

	if (test_opt(sbi, COMPRESS_CACHE))
		seq_puts(seq, ",compress_cache");
}
#endif

static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
{
	struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);

	if (F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_SYNC)
		seq_printf(seq, ",background_gc=%s", "sync");
	else if (F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_ON)
		seq_printf(seq, ",background_gc=%s", "on");
	else if (F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_OFF)
		seq_printf(seq, ",background_gc=%s", "off");

	if (test_opt(sbi, GC_MERGE))
		seq_puts(seq, ",gc_merge");

	if (test_opt(sbi, DISABLE_ROLL_FORWARD))
		seq_puts(seq, ",disable_roll_forward");
	if (test_opt(sbi, NORECOVERY))
		seq_puts(seq, ",norecovery");
	if (test_opt(sbi, DISCARD))
		seq_puts(seq, ",discard");
	else
		seq_puts(seq, ",nodiscard");
	if (test_opt(sbi, NOHEAP))
		seq_puts(seq, ",no_heap");
	else
		seq_puts(seq, ",heap");
#ifdef CONFIG_F2FS_FS_XATTR
	if (test_opt(sbi, XATTR_USER))
		seq_puts(seq, ",user_xattr");
	else
		seq_puts(seq, ",nouser_xattr");
	if (test_opt(sbi, INLINE_XATTR))
		seq_puts(seq, ",inline_xattr");
	else
		seq_puts(seq, ",noinline_xattr");
	if (test_opt(sbi, INLINE_XATTR_SIZE))
		seq_printf(seq, ",inline_xattr_size=%u",
					F2FS_OPTION(sbi).inline_xattr_size);
#endif
#ifdef CONFIG_F2FS_FS_POSIX_ACL
	if (test_opt(sbi, POSIX_ACL))
		seq_puts(seq, ",acl");
	else
		seq_puts(seq, ",noacl");
#endif
	if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
		seq_puts(seq, ",disable_ext_identify");
	if (test_opt(sbi, INLINE_DATA))
		seq_puts(seq, ",inline_data");
	else
		seq_puts(seq, ",noinline_data");
	if (test_opt(sbi, INLINE_DENTRY))
		seq_puts(seq, ",inline_dentry");
	else
		seq_puts(seq, ",noinline_dentry");
	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
		seq_puts(seq, ",flush_merge");
	if (test_opt(sbi, NOBARRIER))
		seq_puts(seq, ",nobarrier");
	if (test_opt(sbi, FASTBOOT))
		seq_puts(seq, ",fastboot");
	if (test_opt(sbi, EXTENT_CACHE))
		seq_puts(seq, ",extent_cache");
	else
		seq_puts(seq, ",noextent_cache");
	if (test_opt(sbi, DATA_FLUSH))
		seq_puts(seq, ",data_flush");

	seq_puts(seq, ",mode=");
	if (F2FS_OPTION(sbi).fs_mode == FS_MODE_ADAPTIVE)
		seq_puts(seq, "adaptive");
	else if (F2FS_OPTION(sbi).fs_mode == FS_MODE_LFS)
		seq_puts(seq, "lfs");
	seq_printf(seq, ",active_logs=%u", F2FS_OPTION(sbi).active_logs);
	if (test_opt(sbi, RESERVE_ROOT))
		seq_printf(seq, ",reserve_root=%u,resuid=%u,resgid=%u",
				F2FS_OPTION(sbi).root_reserved_blocks,
				from_kuid_munged(&init_user_ns,
					F2FS_OPTION(sbi).s_resuid),
				from_kgid_munged(&init_user_ns,
					F2FS_OPTION(sbi).s_resgid));
	if (F2FS_IO_SIZE_BITS(sbi))
		seq_printf(seq, ",io_bits=%u",
				F2FS_OPTION(sbi).write_io_size_bits);
#ifdef CONFIG_F2FS_FAULT_INJECTION
	if (test_opt(sbi, FAULT_INJECTION)) {
		seq_printf(seq, ",fault_injection=%u",
				F2FS_OPTION(sbi).fault_info.inject_rate);
		seq_printf(seq, ",fault_type=%u",
				F2FS_OPTION(sbi).fault_info.inject_type);
	}
#endif
#ifdef CONFIG_QUOTA
	if (test_opt(sbi, QUOTA))
		seq_puts(seq, ",quota");
	if (test_opt(sbi, USRQUOTA))
		seq_puts(seq, ",usrquota");
	if (test_opt(sbi, GRPQUOTA))
		seq_puts(seq, ",grpquota");
	if (test_opt(sbi, PRJQUOTA))
		seq_puts(seq, ",prjquota");
#endif
	f2fs_show_quota_options(seq, sbi->sb);
	if (F2FS_OPTION(sbi).whint_mode == WHINT_MODE_USER)
		seq_printf(seq, ",whint_mode=%s", "user-based");
	else if (F2FS_OPTION(sbi).whint_mode == WHINT_MODE_FS)
		seq_printf(seq, ",whint_mode=%s", "fs-based");

	fscrypt_show_test_dummy_encryption(seq, ',', sbi->sb);

	if (sbi->sb->s_flags & SB_INLINECRYPT)
		seq_puts(seq, ",inlinecrypt");

	if (F2FS_OPTION(sbi).alloc_mode == ALLOC_MODE_DEFAULT)
		seq_printf(seq, ",alloc_mode=%s", "default");
	else if (F2FS_OPTION(sbi).alloc_mode == ALLOC_MODE_REUSE)
		seq_printf(seq, ",alloc_mode=%s", "reuse");

	if (test_opt(sbi, DISABLE_CHECKPOINT))
		seq_printf(seq, ",checkpoint=disable:%u",
				F2FS_OPTION(sbi).unusable_cap);
	if (test_opt(sbi, MERGE_CHECKPOINT))
		seq_puts(seq, ",checkpoint_merge");
	else
		seq_puts(seq, ",nocheckpoint_merge");
	if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_POSIX)
		seq_printf(seq, ",fsync_mode=%s", "posix");
	else if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_STRICT)
		seq_printf(seq, ",fsync_mode=%s", "strict");
	else if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_NOBARRIER)
		seq_printf(seq, ",fsync_mode=%s", "nobarrier");

#ifdef CONFIG_F2FS_FS_COMPRESSION
	f2fs_show_compress_options(seq, sbi->sb);
#endif

	if (test_opt(sbi, ATGC))
		seq_puts(seq, ",atgc");

	if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_BLOCK)
		seq_printf(seq, ",discard_unit=%s", "block");
	else if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SEGMENT)
		seq_printf(seq, ",discard_unit=%s", "segment");
	else if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SECTION)
		seq_printf(seq, ",discard_unit=%s", "section");

	return 0;
}

static void default_options(struct f2fs_sb_info *sbi)
{
	/* init some FS parameters */
	if (f2fs_sb_has_readonly(sbi))
		F2FS_OPTION(sbi).active_logs = NR_CURSEG_RO_TYPE;
	else
		F2FS_OPTION(sbi).active_logs = NR_CURSEG_PERSIST_TYPE;

	F2FS_OPTION(sbi).inline_xattr_size = DEFAULT_INLINE_XATTR_ADDRS;
	F2FS_OPTION(sbi).whint_mode = WHINT_MODE_OFF;
	F2FS_OPTION(sbi).alloc_mode = ALLOC_MODE_DEFAULT;
	F2FS_OPTION(sbi).fsync_mode = FSYNC_MODE_POSIX;
	F2FS_OPTION(sbi).s_resuid = make_kuid(&init_user_ns, F2FS_DEF_RESUID);
	F2FS_OPTION(sbi).s_resgid = make_kgid(&init_user_ns, F2FS_DEF_RESGID);
	F2FS_OPTION(sbi).compress_algorithm = COMPRESS_LZ4;
	F2FS_OPTION(sbi).compress_log_size = MIN_COMPRESS_LOG_SIZE;
	F2FS_OPTION(sbi).compress_ext_cnt = 0;
	F2FS_OPTION(sbi).compress_mode = COMPR_MODE_FS;
	F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_ON;

	set_opt(sbi, INLINE_XATTR);
	set_opt(sbi, INLINE_DATA);
	set_opt(sbi, INLINE_DENTRY);
	set_opt(sbi, EXTENT_CACHE);
	set_opt(sbi, NOHEAP);
	clear_opt(sbi, DISABLE_CHECKPOINT);
	set_opt(sbi, MERGE_CHECKPOINT);
	F2FS_OPTION(sbi).unusable_cap = 0;
	sbi->sb->s_flags |= SB_LAZYTIME;
	set_opt(sbi, FLUSH_MERGE);
	if (f2fs_hw_support_discard(sbi) || f2fs_hw_should_discard(sbi))
		set_opt(sbi, DISCARD);
	if (f2fs_sb_has_blkzoned(sbi)) {
		F2FS_OPTION(sbi).fs_mode = FS_MODE_LFS;
		F2FS_OPTION(sbi).discard_unit = DISCARD_UNIT_SECTION;
	} else {
		F2FS_OPTION(sbi).fs_mode = FS_MODE_ADAPTIVE;
		F2FS_OPTION(sbi).discard_unit = DISCARD_UNIT_BLOCK;
	}

#ifdef CONFIG_F2FS_FS_XATTR
	set_opt(sbi, XATTR_USER);
#endif
#ifdef CONFIG_F2FS_FS_POSIX_ACL
	set_opt(sbi, POSIX_ACL);
#endif

	f2fs_build_fault_attr(sbi, 0, 0);
}

#ifdef CONFIG_QUOTA
static int f2fs_enable_quotas(struct super_block *sb);
#endif

static int f2fs_disable_checkpoint(struct f2fs_sb_info *sbi)
{
	unsigned int s_flags = sbi->sb->s_flags;
	struct cp_control cpc;
	int err = 0;
	int ret;
	block_t unusable;

	if (s_flags & SB_RDONLY) {
		f2fs_err(sbi, "checkpoint=disable on readonly fs");
		return -EINVAL;
	}
	sbi->sb->s_flags |= SB_ACTIVE;

	f2fs_update_time(sbi, DISABLE_TIME);

	while (!f2fs_time_over(sbi, DISABLE_TIME)) {
		down_write(&sbi->gc_lock);
		err = f2fs_gc(sbi, true, false, false, NULL_SEGNO);
		if (err == -ENODATA) {
			err = 0;
			break;
		}
		if (err && err != -EAGAIN)
			break;
	}

	ret = sync_filesystem(sbi->sb);
	if (ret || err) {
		err = ret ? ret : err;
		goto restore_flag;
	}

	unusable = f2fs_get_unusable_blocks(sbi);
	if (f2fs_disable_cp_again(sbi, unusable)) {
		err = -EAGAIN;
		goto restore_flag;
	}

	down_write(&sbi->gc_lock);
	cpc.reason = CP_PAUSE;
	set_sbi_flag(sbi, SBI_CP_DISABLED);
	err = f2fs_write_checkpoint(sbi, &cpc);
	if (err)
		goto out_unlock;

	spin_lock(&sbi->stat_lock);
	sbi->unusable_block_count = unusable;
	spin_unlock(&sbi->stat_lock);

out_unlock:
	up_write(&sbi->gc_lock);
restore_flag:
	sbi->sb->s_flags = s_flags;	/* Restore SB_RDONLY status */
	return err;
}

static void f2fs_enable_checkpoint(struct f2fs_sb_info *sbi)
{
	int retry = DEFAULT_RETRY_IO_COUNT;

	/* we should flush all the data to keep data consistency */
	do {
		sync_inodes_sb(sbi->sb);
		f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
	} while (get_pages(sbi, F2FS_DIRTY_DATA) && retry--);

	if (unlikely(retry < 0))
		f2fs_warn(sbi, "checkpoint=enable has some unwritten data.");

	down_write(&sbi->gc_lock);
	f2fs_dirty_to_prefree(sbi);

	clear_sbi_flag(sbi, SBI_CP_DISABLED);
	set_sbi_flag(sbi, SBI_IS_DIRTY);
	up_write(&sbi->gc_lock);

	f2fs_sync_fs(sbi->sb, 1);

	/* Let's ensure there's no pending checkpoint anymore */
	f2fs_flush_ckpt_thread(sbi);
}

static int f2fs_remount(struct super_block *sb, int *flags, char *data)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	struct f2fs_mount_info org_mount_opt;
	unsigned long old_sb_flags;
	int err;
	bool need_restart_gc = false, need_stop_gc = false;
	bool need_restart_ckpt = false, need_stop_ckpt = false;
	bool need_restart_flush = false, need_stop_flush = false;
	bool need_restart_discard = false, need_stop_discard = false;
	bool no_extent_cache = !test_opt(sbi, EXTENT_CACHE);
	bool enable_checkpoint = !test_opt(sbi, DISABLE_CHECKPOINT);
	bool no_io_align = !F2FS_IO_ALIGNED(sbi);
	bool no_atgc = !test_opt(sbi, ATGC);
	bool no_discard = !test_opt(sbi, DISCARD);
	bool no_compress_cache = !test_opt(sbi, COMPRESS_CACHE);
	bool block_unit_discard = f2fs_block_unit_discard(sbi);
	struct discard_cmd_control *dcc;
#ifdef CONFIG_QUOTA
	int i, j;
#endif

	/*
	 * Save the old mount options in case we
	 * need to restore them.
	 */
	org_mount_opt = sbi->mount_opt;
	old_sb_flags = sb->s_flags;

#ifdef CONFIG_QUOTA
	org_mount_opt.s_jquota_fmt = F2FS_OPTION(sbi).s_jquota_fmt;
	for (i = 0; i < MAXQUOTAS; i++) {
		if (F2FS_OPTION(sbi).s_qf_names[i]) {
			org_mount_opt.s_qf_names[i] =
				kstrdup(F2FS_OPTION(sbi).s_qf_names[i],
				GFP_KERNEL);
			if (!org_mount_opt.s_qf_names[i]) {
				for (j = 0; j < i; j++)
					kfree(org_mount_opt.s_qf_names[j]);
				return -ENOMEM;
			}
		} else {
			org_mount_opt.s_qf_names[i] = NULL;
		}
	}
#endif

	/* recover superblocks we couldn't write due to previous RO mount */
	if (!(*flags & SB_RDONLY) && is_sbi_flag_set(sbi, SBI_NEED_SB_WRITE)) {
		err = f2fs_commit_super(sbi, false);
		f2fs_info(sbi, "Try to recover all the superblocks, ret: %d",
			  err);
		if (!err)
			clear_sbi_flag(sbi, SBI_NEED_SB_WRITE);
	}

	default_options(sbi);

	/* parse mount options */
	err = parse_options(sb, data, true);
	if (err)
		goto restore_opts;

	/*
	 * Previous and new state of filesystem is RO,
	 * so skip checking GC and FLUSH_MERGE conditions.
	 */
	if (f2fs_readonly(sb) && (*flags & SB_RDONLY))
		goto skip;

	if (f2fs_dev_is_readonly(sbi) && !(*flags & SB_RDONLY)) {
		err = -EROFS;
		goto restore_opts;
	}

#ifdef CONFIG_QUOTA
	if (!f2fs_readonly(sb) && (*flags & SB_RDONLY)) {
		err = dquot_suspend(sb, -1);
		if (err < 0)
			goto restore_opts;
	} else if (f2fs_readonly(sb) && !(*flags & SB_RDONLY)) {
		/* dquot_resume needs RW */
		sb->s_flags &= ~SB_RDONLY;
		if (sb_any_quota_suspended(sb)) {
			dquot_resume(sb, -1);
		} else if (f2fs_sb_has_quota_ino(sbi)) {
			err = f2fs_enable_quotas(sb);
			if (err)
				goto restore_opts;
		}
	}
#endif
	/* disallow enable atgc dynamically */
	if (no_atgc == !!test_opt(sbi, ATGC)) {
		err = -EINVAL;
		f2fs_warn(sbi, "switch atgc option is not allowed");
		goto restore_opts;
	}

	/* disallow enable/disable extent_cache dynamically */
	if (no_extent_cache == !!test_opt(sbi, EXTENT_CACHE)) {
		err = -EINVAL;
		f2fs_warn(sbi, "switch extent_cache option is not allowed");
		goto restore_opts;
	}

	if (no_io_align == !!F2FS_IO_ALIGNED(sbi)) {
		err = -EINVAL;
		f2fs_warn(sbi, "switch io_bits option is not allowed");
		goto restore_opts;
	}

	if (no_compress_cache == !!test_opt(sbi, COMPRESS_CACHE)) {
		err = -EINVAL;
		f2fs_warn(sbi, "switch compress_cache option is not allowed");
		goto restore_opts;
	}

	if (block_unit_discard != f2fs_block_unit_discard(sbi)) {
		err = -EINVAL;
		f2fs_warn(sbi, "switch discard_unit option is not allowed");
		goto restore_opts;
	}

	if ((*flags & SB_RDONLY) && test_opt(sbi, DISABLE_CHECKPOINT)) {
		err = -EINVAL;
		f2fs_warn(sbi, "disabling checkpoint not compatible with read-only");
		goto restore_opts;
	}

	/*
	 * We stop the GC thread if FS is mounted as RO
	 * or if background_gc = off is passed in mount
	 * option. Also sync the filesystem.
	 */
	if ((*flags & SB_RDONLY) ||
			(F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_OFF &&
			!test_opt(sbi, GC_MERGE))) {
		if (sbi->gc_thread) {
			f2fs_stop_gc_thread(sbi);
			need_restart_gc = true;
		}
	} else if (!sbi->gc_thread) {
		err = f2fs_start_gc_thread(sbi);
		if (err)
			goto restore_opts;
		need_stop_gc = true;
	}

	if (*flags & SB_RDONLY ||
		F2FS_OPTION(sbi).whint_mode != org_mount_opt.whint_mode) {
		sync_inodes_sb(sb);

		set_sbi_flag(sbi, SBI_IS_DIRTY);
		set_sbi_flag(sbi, SBI_IS_CLOSE);
		f2fs_sync_fs(sb, 1);
		clear_sbi_flag(sbi, SBI_IS_CLOSE);
	}

	if ((*flags & SB_RDONLY) || test_opt(sbi, DISABLE_CHECKPOINT) ||
			!test_opt(sbi, MERGE_CHECKPOINT)) {
		f2fs_stop_ckpt_thread(sbi);
		need_restart_ckpt = true;
	} else {
		/* Flush if the prevous checkpoint, if exists. */
		f2fs_flush_ckpt_thread(sbi);

		err = f2fs_start_ckpt_thread(sbi);
		if (err) {
			f2fs_err(sbi,
			    "Failed to start F2FS issue_checkpoint_thread (%d)",
			    err);
			goto restore_gc;
		}
		need_stop_ckpt = true;
	}

	/*
	 * We stop issue flush thread if FS is mounted as RO
	 * or if flush_merge is not passed in mount option.
	 */
	if ((*flags & SB_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
		clear_opt(sbi, FLUSH_MERGE);
		f2fs_destroy_flush_cmd_control(sbi, false);
		need_restart_flush = true;
	} else {
		err = f2fs_create_flush_cmd_control(sbi);
		if (err)
			goto restore_ckpt;
		need_stop_flush = true;
	}

	if (no_discard == !!test_opt(sbi, DISCARD)) {
		if (test_opt(sbi, DISCARD)) {
			err = f2fs_start_discard_thread(sbi);
			if (err)
				goto restore_flush;
			need_stop_discard = true;
		} else {
			dcc = SM_I(sbi)->dcc_info;
			f2fs_stop_discard_thread(sbi);
			if (atomic_read(&dcc->discard_cmd_cnt))
				f2fs_issue_discard_timeout(sbi);
			need_restart_discard = true;
		}
	}

	if (enable_checkpoint == !!test_opt(sbi, DISABLE_CHECKPOINT)) {
		if (test_opt(sbi, DISABLE_CHECKPOINT)) {
			err = f2fs_disable_checkpoint(sbi);
			if (err)
				goto restore_discard;
		} else {
			f2fs_enable_checkpoint(sbi);
		}
	}

skip:
#ifdef CONFIG_QUOTA
	/* Release old quota file names */
	for (i = 0; i < MAXQUOTAS; i++)
		kfree(org_mount_opt.s_qf_names[i]);
#endif
	/* Update the POSIXACL Flag */
	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
		(test_opt(sbi, POSIX_ACL) ? SB_POSIXACL : 0);

	limit_reserve_root(sbi);
	adjust_unusable_cap_perc(sbi);
	*flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
	return 0;
restore_discard:
	if (need_restart_discard) {
		if (f2fs_start_discard_thread(sbi))
			f2fs_warn(sbi, "discard has been stopped");
	} else if (need_stop_discard) {
		f2fs_stop_discard_thread(sbi);
	}
restore_flush:
	if (need_restart_flush) {
		if (f2fs_create_flush_cmd_control(sbi))
			f2fs_warn(sbi, "background flush thread has stopped");
	} else if (need_stop_flush) {
		clear_opt(sbi, FLUSH_MERGE);
		f2fs_destroy_flush_cmd_control(sbi, false);
	}
restore_ckpt:
	if (need_restart_ckpt) {
		if (f2fs_start_ckpt_thread(sbi))
			f2fs_warn(sbi, "background ckpt thread has stopped");
	} else if (need_stop_ckpt) {
		f2fs_stop_ckpt_thread(sbi);
	}
restore_gc:
	if (need_restart_gc) {
		if (f2fs_start_gc_thread(sbi))
			f2fs_warn(sbi, "background gc thread has stopped");
	} else if (need_stop_gc) {
		f2fs_stop_gc_thread(sbi);
	}
restore_opts:
#ifdef CONFIG_QUOTA
	F2FS_OPTION(sbi).s_jquota_fmt = org_mount_opt.s_jquota_fmt;
	for (i = 0; i < MAXQUOTAS; i++) {
		kfree(F2FS_OPTION(sbi).s_qf_names[i]);
		F2FS_OPTION(sbi).s_qf_names[i] = org_mount_opt.s_qf_names[i];
	}
#endif
	sbi->mount_opt = org_mount_opt;
	sb->s_flags = old_sb_flags;
	return err;
}

#ifdef CONFIG_QUOTA
/* Read data from quotafile */
static ssize_t f2fs_quota_read(struct super_block *sb, int type, char *data,
			       size_t len, loff_t off)
{
	struct inode *inode = sb_dqopt(sb)->files[type];
	struct address_space *mapping = inode->i_mapping;
	block_t blkidx = F2FS_BYTES_TO_BLK(off);
	int offset = off & (sb->s_blocksize - 1);
	int tocopy;
	size_t toread;
	loff_t i_size = i_size_read(inode);
	struct page *page;

	if (off > i_size)
		return 0;

	if (off + len > i_size)
		len = i_size - off;
	toread = len;
	while (toread > 0) {
		tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
repeat:
		page = read_cache_page_gfp(mapping, blkidx, GFP_NOFS);
		if (IS_ERR(page)) {
			if (PTR_ERR(page) == -ENOMEM) {
				congestion_wait(BLK_RW_ASYNC,
						DEFAULT_IO_TIMEOUT);
				goto repeat;
			}
			set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);
			return PTR_ERR(page);
		}

		lock_page(page);

		if (unlikely(page->mapping != mapping)) {
			f2fs_put_page(page, 1);
			goto repeat;
		}
		if (unlikely(!PageUptodate(page))) {
			f2fs_put_page(page, 1);
			set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);
			return -EIO;
		}

		memcpy_from_page(data, page, offset, tocopy);
		f2fs_put_page(page, 1);

		offset = 0;
		toread -= tocopy;
		data += tocopy;
		blkidx++;
	}
	return len;
}

/* Write to quotafile */
static ssize_t f2fs_quota_write(struct super_block *sb, int type,
				const char *data, size_t len, loff_t off)
{
	struct inode *inode = sb_dqopt(sb)->files[type];
	struct address_space *mapping = inode->i_mapping;
	const struct address_space_operations *a_ops = mapping->a_ops;
	int offset = off & (sb->s_blocksize - 1);
	size_t towrite = len;
	struct page *page;
	void *fsdata = NULL;
	int err = 0;
	int tocopy;

	while (towrite > 0) {
		tocopy = min_t(unsigned long, sb->s_blocksize - offset,
								towrite);
retry:
		err = a_ops->write_begin(NULL, mapping, off, tocopy, 0,
							&page, &fsdata);
		if (unlikely(err)) {
			if (err == -ENOMEM) {
				f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
				goto retry;
			}
			set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);
			break;
		}

		memcpy_to_page(page, offset, data, tocopy);

		a_ops->write_end(NULL, mapping, off, tocopy, tocopy,
						page, fsdata);
		offset = 0;
		towrite -= tocopy;
		off += tocopy;
		data += tocopy;
		cond_resched();
	}

	if (len == towrite)
		return err;
	inode->i_mtime = inode->i_ctime = current_time(inode);
	f2fs_mark_inode_dirty_sync(inode, false);
	return len - towrite;
}

int f2fs_dquot_initialize(struct inode *inode)
{
	if (time_to_inject(F2FS_I_SB(inode), FAULT_DQUOT_INIT)) {
		f2fs_show_injection_info(F2FS_I_SB(inode), FAULT_DQUOT_INIT);
		return -ESRCH;
	}

	return dquot_initialize(inode);
}

static struct dquot **f2fs_get_dquots(struct inode *inode)
{
	return F2FS_I(inode)->i_dquot;
}

static qsize_t *f2fs_get_reserved_space(struct inode *inode)
{
	return &F2FS_I(inode)->i_reserved_quota;
}

static int f2fs_quota_on_mount(struct f2fs_sb_info *sbi, int type)
{
	if (is_set_ckpt_flags(sbi, CP_QUOTA_NEED_FSCK_FLAG)) {
		f2fs_err(sbi, "quota sysfile may be corrupted, skip loading it");
		return 0;
	}

	return dquot_quota_on_mount(sbi->sb, F2FS_OPTION(sbi).s_qf_names[type],
					F2FS_OPTION(sbi).s_jquota_fmt, type);
}

int f2fs_enable_quota_files(struct f2fs_sb_info *sbi, bool rdonly)
{
	int enabled = 0;
	int i, err;

	if (f2fs_sb_has_quota_ino(sbi) && rdonly) {
		err = f2fs_enable_quotas(sbi->sb);
		if (err) {
			f2fs_err(sbi, "Cannot turn on quota_ino: %d", err);
			return 0;
		}
		return 1;
	}

	for (i = 0; i < MAXQUOTAS; i++) {
		if (F2FS_OPTION(sbi).s_qf_names[i]) {
			err = f2fs_quota_on_mount(sbi, i);
			if (!err) {
				enabled = 1;
				continue;
			}
			f2fs_err(sbi, "Cannot turn on quotas: %d on %d",
				 err, i);
		}
	}
	return enabled;
}

static int f2fs_quota_enable(struct super_block *sb, int type, int format_id,
			     unsigned int flags)
{
	struct inode *qf_inode;
	unsigned long qf_inum;
	int err;

	BUG_ON(!f2fs_sb_has_quota_ino(F2FS_SB(sb)));

	qf_inum = f2fs_qf_ino(sb, type);
	if (!qf_inum)
		return -EPERM;

	qf_inode = f2fs_iget(sb, qf_inum);
	if (IS_ERR(qf_inode)) {
		f2fs_err(F2FS_SB(sb), "Bad quota inode %u:%lu", type, qf_inum);
		return PTR_ERR(qf_inode);
	}

	/* Don't account quota for quota files to avoid recursion */
	qf_inode->i_flags |= S_NOQUOTA;
	err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
	iput(qf_inode);
	return err;
}

static int f2fs_enable_quotas(struct super_block *sb)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	int type, err = 0;
	unsigned long qf_inum;
	bool quota_mopt[MAXQUOTAS] = {
		test_opt(sbi, USRQUOTA),
		test_opt(sbi, GRPQUOTA),
		test_opt(sbi, PRJQUOTA),
	};

	if (is_set_ckpt_flags(F2FS_SB(sb), CP_QUOTA_NEED_FSCK_FLAG)) {
		f2fs_err(sbi, "quota file may be corrupted, skip loading it");
		return 0;
	}

	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;

	for (type = 0; type < MAXQUOTAS; type++) {
		qf_inum = f2fs_qf_ino(sb, type);
		if (qf_inum) {
			err = f2fs_quota_enable(sb, type, QFMT_VFS_V1,
				DQUOT_USAGE_ENABLED |
				(quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
			if (err) {
				f2fs_err(sbi, "Failed to enable quota tracking (type=%d, err=%d). Please run fsck to fix.",
					 type, err);
				for (type--; type >= 0; type--)
					dquot_quota_off(sb, type);
				set_sbi_flag(F2FS_SB(sb),
						SBI_QUOTA_NEED_REPAIR);
				return err;
			}
		}
	}
	return 0;
}

static int f2fs_quota_sync_file(struct f2fs_sb_info *sbi, int type)
{
	struct quota_info *dqopt = sb_dqopt(sbi->sb);
	struct address_space *mapping = dqopt->files[type]->i_mapping;
	int ret = 0;

	ret = dquot_writeback_dquots(sbi->sb, type);
	if (ret)
		goto out;

	ret = filemap_fdatawrite(mapping);
	if (ret)
		goto out;

	/* if we are using journalled quota */
	if (is_journalled_quota(sbi))
		goto out;

	ret = filemap_fdatawait(mapping);

	truncate_inode_pages(&dqopt->files[type]->i_data, 0);
out:
	if (ret)
		set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
	return ret;
}

int f2fs_quota_sync(struct super_block *sb, int type)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	struct quota_info *dqopt = sb_dqopt(sb);
	int cnt;
	int ret = 0;

	/*
	 * Now when everything is written we can discard the pagecache so
	 * that userspace sees the changes.
	 */
	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		if (type != -1 && cnt != type)
			continue;

		if (!sb_has_quota_active(sb, cnt))
			continue;

		if (!f2fs_sb_has_quota_ino(sbi))
			inode_lock(dqopt->files[cnt]);

		/*
		 * do_quotactl
		 *  f2fs_quota_sync
		 *  down_read(quota_sem)
		 *  dquot_writeback_dquots()
		 *  f2fs_dquot_commit
		 *			      block_operation
		 *			      down_read(quota_sem)
		 */
		f2fs_lock_op(sbi);
		down_read(&sbi->quota_sem);

		ret = f2fs_quota_sync_file(sbi, cnt);

		up_read(&sbi->quota_sem);
		f2fs_unlock_op(sbi);

		if (!f2fs_sb_has_quota_ino(sbi))
			inode_unlock(dqopt->files[cnt]);

		if (ret)
			break;
	}
	return ret;
}

static int f2fs_quota_on(struct super_block *sb, int type, int format_id,
							const struct path *path)
{
	struct inode *inode;
	int err;

	/* if quota sysfile exists, deny enabling quota with specific file */
	if (f2fs_sb_has_quota_ino(F2FS_SB(sb))) {
		f2fs_err(F2FS_SB(sb), "quota sysfile already exists");
		return -EBUSY;
	}

	err = f2fs_quota_sync(sb, type);
	if (err)
		return err;

	err = dquot_quota_on(sb, type, format_id, path);
	if (err)
		return err;

	inode = d_inode(path->dentry);

	inode_lock(inode);
	F2FS_I(inode)->i_flags |= F2FS_NOATIME_FL | F2FS_IMMUTABLE_FL;
	f2fs_set_inode_flags(inode);
	inode_unlock(inode);
	f2fs_mark_inode_dirty_sync(inode, false);

	return 0;
}

static int __f2fs_quota_off(struct super_block *sb, int type)
{
	struct inode *inode = sb_dqopt(sb)->files[type];
	int err;

	if (!inode || !igrab(inode))
		return dquot_quota_off(sb, type);

	err = f2fs_quota_sync(sb, type);
	if (err)
		goto out_put;

	err = dquot_quota_off(sb, type);
	if (err || f2fs_sb_has_quota_ino(F2FS_SB(sb)))
		goto out_put;

	inode_lock(inode);
	F2FS_I(inode)->i_flags &= ~(F2FS_NOATIME_FL | F2FS_IMMUTABLE_FL);
	f2fs_set_inode_flags(inode);
	inode_unlock(inode);
	f2fs_mark_inode_dirty_sync(inode, false);
out_put:
	iput(inode);
	return err;
}

static int f2fs_quota_off(struct super_block *sb, int type)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	int err;

	err = __f2fs_quota_off(sb, type);

	/*
	 * quotactl can shutdown journalled quota, result in inconsistence
	 * between quota record and fs data by following updates, tag the
	 * flag to let fsck be aware of it.
	 */
	if (is_journalled_quota(sbi))
		set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
	return err;
}

void f2fs_quota_off_umount(struct super_block *sb)
{
	int type;
	int err;

	for (type = 0; type < MAXQUOTAS; type++) {
		err = __f2fs_quota_off(sb, type);
		if (err) {
			int ret = dquot_quota_off(sb, type);

			f2fs_err(F2FS_SB(sb), "Fail to turn off disk quota (type: %d, err: %d, ret:%d), Please run fsck to fix it.",
				 type, err, ret);
			set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);
		}
	}
	/*
	 * In case of checkpoint=disable, we must flush quota blocks.
	 * This can cause NULL exception for node_inode in end_io, since
	 * put_super already dropped it.
	 */
	sync_filesystem(sb);
}

static void f2fs_truncate_quota_inode_pages(struct super_block *sb)
{
	struct quota_info *dqopt = sb_dqopt(sb);
	int type;

	for (type = 0; type < MAXQUOTAS; type++) {
		if (!dqopt->files[type])
			continue;
		f2fs_inode_synced(dqopt->files[type]);
	}
}

static int f2fs_dquot_commit(struct dquot *dquot)
{
	struct f2fs_sb_info *sbi = F2FS_SB(dquot->dq_sb);
	int ret;

	down_read_nested(&sbi->quota_sem, SINGLE_DEPTH_NESTING);
	ret = dquot_commit(dquot);
	if (ret < 0)
		set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
	up_read(&sbi->quota_sem);
	return ret;
}

static int f2fs_dquot_acquire(struct dquot *dquot)
{
	struct f2fs_sb_info *sbi = F2FS_SB(dquot->dq_sb);
	int ret;

	down_read(&sbi->quota_sem);
	ret = dquot_acquire(dquot);
	if (ret < 0)
		set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
	up_read(&sbi->quota_sem);
	return ret;
}

static int f2fs_dquot_release(struct dquot *dquot)
{
	struct f2fs_sb_info *sbi = F2FS_SB(dquot->dq_sb);
	int ret = dquot_release(dquot);

	if (ret < 0)
		set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
	return ret;
}

static int f2fs_dquot_mark_dquot_dirty(struct dquot *dquot)
{
	struct super_block *sb = dquot->dq_sb;
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	int ret = dquot_mark_dquot_dirty(dquot);

	/* if we are using journalled quota */
	if (is_journalled_quota(sbi))
		set_sbi_flag(sbi, SBI_QUOTA_NEED_FLUSH);

	return ret;
}

static int f2fs_dquot_commit_info(struct super_block *sb, int type)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	int ret = dquot_commit_info(sb, type);

	if (ret < 0)
		set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
	return ret;
}

static int f2fs_get_projid(struct inode *inode, kprojid_t *projid)
{
	*projid = F2FS_I(inode)->i_projid;
	return 0;
}

static const struct dquot_operations f2fs_quota_operations = {
	.get_reserved_space = f2fs_get_reserved_space,
	.write_dquot	= f2fs_dquot_commit,
	.acquire_dquot	= f2fs_dquot_acquire,
	.release_dquot	= f2fs_dquot_release,
	.mark_dirty	= f2fs_dquot_mark_dquot_dirty,
	.write_info	= f2fs_dquot_commit_info,
	.alloc_dquot	= dquot_alloc,
	.destroy_dquot	= dquot_destroy,
	.get_projid	= f2fs_get_projid,
	.get_next_id	= dquot_get_next_id,
};

static const struct quotactl_ops f2fs_quotactl_ops = {
	.quota_on	= f2fs_quota_on,
	.quota_off	= f2fs_quota_off,
	.quota_sync	= f2fs_quota_sync,
	.get_state	= dquot_get_state,
	.set_info	= dquot_set_dqinfo,
	.get_dqblk	= dquot_get_dqblk,
	.set_dqblk	= dquot_set_dqblk,
	.get_nextdqblk	= dquot_get_next_dqblk,
};
#else
int f2fs_dquot_initialize(struct inode *inode)
{
	return 0;
}

int f2fs_quota_sync(struct super_block *sb, int type)
{
	return 0;
}

void f2fs_quota_off_umount(struct super_block *sb)
{
}
#endif

static const struct super_operations f2fs_sops = {
	.alloc_inode	= f2fs_alloc_inode,
	.free_inode	= f2fs_free_inode,
	.drop_inode	= f2fs_drop_inode,
	.write_inode	= f2fs_write_inode,
	.dirty_inode	= f2fs_dirty_inode,
	.show_options	= f2fs_show_options,
#ifdef CONFIG_QUOTA
	.quota_read	= f2fs_quota_read,
	.quota_write	= f2fs_quota_write,
	.get_dquots	= f2fs_get_dquots,
#endif
	.evict_inode	= f2fs_evict_inode,
	.put_super	= f2fs_put_super,
	.sync_fs	= f2fs_sync_fs,
	.freeze_fs	= f2fs_freeze,
	.unfreeze_fs	= f2fs_unfreeze,
	.statfs		= f2fs_statfs,
	.remount_fs	= f2fs_remount,
};

#ifdef CONFIG_FS_ENCRYPTION
static int f2fs_get_context(struct inode *inode, void *ctx, size_t len)
{
	return f2fs_getxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
				F2FS_XATTR_NAME_ENCRYPTION_CONTEXT,
				ctx, len, NULL);
}

static int f2fs_set_context(struct inode *inode, const void *ctx, size_t len,
							void *fs_data)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

	/*
	 * Encrypting the root directory is not allowed because fsck
	 * expects lost+found directory to exist and remain unencrypted
	 * if LOST_FOUND feature is enabled.
	 *
	 */
	if (f2fs_sb_has_lost_found(sbi) &&
			inode->i_ino == F2FS_ROOT_INO(sbi))
		return -EPERM;

	return f2fs_setxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
				F2FS_XATTR_NAME_ENCRYPTION_CONTEXT,
				ctx, len, fs_data, XATTR_CREATE);
}

static const union fscrypt_policy *f2fs_get_dummy_policy(struct super_block *sb)
{
	return F2FS_OPTION(F2FS_SB(sb)).dummy_enc_policy.policy;
}

static bool f2fs_has_stable_inodes(struct super_block *sb)
{
	return true;
}

static void f2fs_get_ino_and_lblk_bits(struct super_block *sb,
				       int *ino_bits_ret, int *lblk_bits_ret)
{
	*ino_bits_ret = 8 * sizeof(nid_t);
	*lblk_bits_ret = 8 * sizeof(block_t);
}

static int f2fs_get_num_devices(struct super_block *sb)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);

	if (f2fs_is_multi_device(sbi))
		return sbi->s_ndevs;
	return 1;
}

static void f2fs_get_devices(struct super_block *sb,
			     struct request_queue **devs)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	int i;

	for (i = 0; i < sbi->s_ndevs; i++)
		devs[i] = bdev_get_queue(FDEV(i).bdev);
}

static const struct fscrypt_operations f2fs_cryptops = {
	.key_prefix		= "f2fs:",
	.get_context		= f2fs_get_context,
	.set_context		= f2fs_set_context,
	.get_dummy_policy	= f2fs_get_dummy_policy,
	.empty_dir		= f2fs_empty_dir,
	.max_namelen		= F2FS_NAME_LEN,
	.has_stable_inodes	= f2fs_has_stable_inodes,
	.get_ino_and_lblk_bits	= f2fs_get_ino_and_lblk_bits,
	.get_num_devices	= f2fs_get_num_devices,
	.get_devices		= f2fs_get_devices,
};
#endif

static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
		u64 ino, u32 generation)
{
	struct f2fs_sb_info *sbi = F2FS_SB(sb);
	struct inode *inode;

	if (f2fs_check_nid_range(sbi, ino))
		return ERR_PTR(-ESTALE);

	/*
	 * f2fs_iget isn't quite right if the inode is currently unallocated!
	 * However f2fs_iget currently does appropriate checks to handle stale
	 * inodes so everything is OK.
	 */
	inode = f2fs_iget(sb, ino);
	if (IS_ERR(inode))
		return ERR_CAST(inode);
	if (unlikely(generation && inode->i_generation != generation)) {
		/* we didn't find the right inode.. */
		iput(inode);
		return ERR_PTR(-ESTALE);
	}
	return inode;
}

static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
		int fh_len, int fh_type)
{
	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
				    f2fs_nfs_get_inode);
}

static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
		int fh_len, int fh_type)
{
	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
				    f2fs_nfs_get_inode);
}

static const struct export_operations f2fs_export_ops = {
	.fh_to_dentry = f2fs_fh_to_dentry,
	.fh_to_parent = f2fs_fh_to_parent,
	.get_parent = f2fs_get_parent,
};

loff_t max_file_blocks(struct inode *inode)
{
	loff_t result = 0;
	loff_t leaf_count;

	/*
	 * note: previously, result is equal to (DEF_ADDRS_PER_INODE -
	 * DEFAULT_INLINE_XATTR_ADDRS), but now f2fs try to reserve more
	 * space in inode.i_addr, it will be more safe to reassign
	 * result as zero.
	 */

	if (inode && f2fs_compressed_file(inode))
		leaf_count = ADDRS_PER_BLOCK(inode);
	else
		leaf_count = DEF_ADDRS_PER_BLOCK;

	/* two direct node blocks */
	result += (leaf_count * 2);

	/* two indirect node blocks */
	leaf_count *= NIDS_PER_BLOCK;
	result += (leaf_count * 2);

	/* one double indirect node block */
	leaf_count *= NIDS_PER_BLOCK;
	result += leaf_count;

	return result;
}

static int __f2fs_commit_super(struct buffer_head *bh,
			struct f2fs_super_block *super)
{
	lock_buffer(bh);
	if (super)
		memcpy(bh->b_data + F2FS_SUPER_OFFSET, super, sizeof(*super));
	set_buffer_dirty(bh);
	unlock_buffer(bh);

	/* it's rare case, we can do fua all the time */
	return __sync_dirty_buffer(bh, REQ_SYNC | REQ_PREFLUSH | REQ_FUA);
}

static inline bool sanity_check_area_boundary(struct f2fs_sb_info *sbi,
					struct buffer_head *bh)
{
	struct f2fs_super_block *raw_super = (struct f2fs_super_block *)
					(bh->b_data + F2FS_SUPER_OFFSET);
	struct super_block *sb = sbi->sb;
	u32 segment0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
	u32 cp_blkaddr = le32_to_cpu(raw_super->cp_blkaddr);
	u32 sit_blkaddr = le32_to_cpu(raw_super->sit_blkaddr);
	u32 nat_blkaddr = le32_to_cpu(raw_super->nat_blkaddr);
	u32 ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
	u32 main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
	u32 segment_count_ckpt = le32_to_cpu(raw_super->segment_count_ckpt);
	u32 segment_count_sit = le32_to_cpu(raw_super->segment_count_sit);
	u32 segment_count_nat = le32_to_cpu(raw_super->segment_count_nat);
	u32 segment_count_ssa = le32_to_cpu(raw_super->segment_count_ssa);
	u32 segment_count_main = le32_to_cpu(raw_super->segment_count_main);
	u32 segment_count = le32_to_cpu(raw_super->segment_count);
	u32 log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
	u64 main_end_blkaddr = main_blkaddr +
				(segment_count_main << log_blocks_per_seg);
	u64 seg_end_blkaddr = segment0_blkaddr +
				(segment_count << log_blocks_per_seg);

	if (segment0_blkaddr != cp_blkaddr) {
		f2fs_info(sbi, "Mismatch start address, segment0(%u) cp_blkaddr(%u)",
			  segment0_blkaddr, cp_blkaddr);
		return true;
	}

	if (cp_blkaddr + (segment_count_ckpt << log_blocks_per_seg) !=
							sit_blkaddr) {
		f2fs_info(sbi, "Wrong CP boundary, start(%u) end(%u) blocks(%u)",
			  cp_blkaddr, sit_blkaddr,
			  segment_count_ckpt << log_blocks_per_seg);
		return true;
	}

	if (sit_blkaddr + (segment_count_sit << log_blocks_per_seg) !=
							nat_blkaddr) {
		f2fs_info(sbi, "Wrong SIT boundary, start(%u) end(%u) blocks(%u)",
			  sit_blkaddr, nat_blkaddr,
			  segment_count_sit << log_blocks_per_seg);
		return true;
	}

	if (nat_blkaddr + (segment_count_nat << log_blocks_per_seg) !=
							ssa_blkaddr) {
		f2fs_info(sbi, "Wrong NAT boundary, start(%u) end(%u) blocks(%u)",
			  nat_blkaddr, ssa_blkaddr,
			  segment_count_nat << log_blocks_per_seg);
		return true;
	}

	if (ssa_blkaddr + (segment_count_ssa << log_blocks_per_seg) !=
							main_blkaddr) {
		f2fs_info(sbi, "Wrong SSA boundary, start(%u) end(%u) blocks(%u)",
			  ssa_blkaddr, main_blkaddr,
			  segment_count_ssa << log_blocks_per_seg);
		return true;
	}

	if (main_end_blkaddr > seg_end_blkaddr) {
		f2fs_info(sbi, "Wrong MAIN_AREA boundary, start(%u) end(%llu) block(%u)",
			  main_blkaddr, seg_end_blkaddr,
			  segment_count_main << log_blocks_per_seg);
		return true;
	} else if (main_end_blkaddr < seg_end_blkaddr) {
		int err = 0;
		char *res;

		/* fix in-memory information all the time */
		raw_super->segment_count = cpu_to_le32((main_end_blkaddr -
				segment0_blkaddr) >> log_blocks_per_seg);

		if (f2fs_readonly(sb) || bdev_read_only(sb->s_bdev)) {
			set_sbi_flag(sbi, SBI_NEED_SB_WRITE);
			res = "internally";
		} else {
			err = __f2fs_commit_super(bh, NULL);
			res = err ? "failed" : "done";
		}
		f2fs_info(sbi, "Fix alignment : %s, start(%u) end(%llu) block(%u)",
			  res, main_blkaddr, seg_end_blkaddr,
			  segment_count_main << log_blocks_per_seg);
		if (err)
			return true;
	}
	return false;
}

static int sanity_check_raw_super(struct f2fs_sb_info *sbi,
				struct buffer_head *bh)
{
	block_t segment_count, segs_per_sec, secs_per_zone, segment_count_main;
	block_t total_sections, blocks_per_seg;
	struct f2fs_super_block *raw_super = (struct f2fs_super_block *)
					(bh->b_data + F2FS_SUPER_OFFSET);
	size_t crc_offset = 0;
	__u32 crc = 0;

	if (le32_to_cpu(raw_super->magic) != F2FS_SUPER_MAGIC) {
		f2fs_info(sbi, "Magic Mismatch, valid(0x%x) - read(0x%x)",
			  F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
		return -EINVAL;
	}

	/* Check checksum_offset and crc in superblock */
	if (__F2FS_HAS_FEATURE(raw_super, F2FS_FEATURE_SB_CHKSUM)) {
		crc_offset = le32_to_cpu(raw_super->checksum_offset);
		if (crc_offset !=
			offsetof(struct f2fs_super_block, crc)) {
			f2fs_info(sbi, "Invalid SB checksum offset: %zu",
				  crc_offset);
			return -EFSCORRUPTED;
		}
		crc = le32_to_cpu(raw_super->crc);
		if (!f2fs_crc_valid(sbi, crc, raw_super, crc_offset)) {
			f2fs_info(sbi, "Invalid SB checksum value: %u", crc);
			return -EFSCORRUPTED;
		}
	}

	/* Currently, support only 4KB block size */
	if (le32_to_cpu(raw_super->log_blocksize) != F2FS_BLKSIZE_BITS) {
		f2fs_info(sbi, "Invalid log_blocksize (%u), supports only %u",
			  le32_to_cpu(raw_super->log_blocksize),
			  F2FS_BLKSIZE_BITS);
		return -EFSCORRUPTED;
	}

	/* check log blocks per segment */
	if (le32_to_cpu(raw_super->log_blocks_per_seg) != 9) {
		f2fs_info(sbi, "Invalid log blocks per segment (%u)",
			  le32_to_cpu(raw_super->log_blocks_per_seg));
		return -EFSCORRUPTED;
	}

	/* Currently, support 512/1024/2048/4096 bytes sector size */
	if (le32_to_cpu(raw_super->log_sectorsize) >
				F2FS_MAX_LOG_SECTOR_SIZE ||
		le32_to_cpu(raw_super->log_sectorsize) <
				F2FS_MIN_LOG_SECTOR_SIZE) {
		f2fs_info(sbi, "Invalid log sectorsize (%u)",
			  le32_to_cpu(raw_super->log_sectorsize));
		return -EFSCORRUPTED;
	}
	if (le32_to_cpu(raw_super->log_sectors_per_block) +
		le32_to_cpu(raw_super->log_sectorsize) !=
			F2FS_MAX_LOG_SECTOR_SIZE) {
		f2fs_info(sbi, "Invalid log sectors per block(%u) log sectorsize(%u)",
			  le32_to_cpu(raw_super->log_sectors_per_block),
			  le32_to_cpu(raw_super->log_sectorsize));
		return -EFSCORRUPTED;
	}

	segment_count = le32_to_cpu(raw_super->segment_count);
	segment_count_main = le32_to_cpu(raw_super->segment_count_main);
	segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
	secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
	total_sections = le32_to_cpu(raw_super->section_count);

	/* blocks_per_seg should be 512, given the above check */
	blocks_per_seg = 1 << le32_to_cpu(raw_super->log_blocks_per_seg);

	if (segment_count > F2FS_MAX_SEGMENT ||
				segment_count < F2FS_MIN_SEGMENTS) {
		f2fs_info(sbi, "Invalid segment count (%u)", segment_count);
		return -EFSCORRUPTED;
	}

	if (total_sections > segment_count_main || total_sections < 1 ||
			segs_per_sec > segment_count || !segs_per_sec) {
		f2fs_info(sbi, "Invalid segment/section count (%u, %u x %u)",
			  segment_count, total_sections, segs_per_sec);
		return -EFSCORRUPTED;
	}

	if (segment_count_main != total_sections * segs_per_sec) {
		f2fs_info(sbi, "Invalid segment/section count (%u != %u * %u)",
			  segment_count_main, total_sections, segs_per_sec);
		return -EFSCORRUPTED;
	}

	if ((segment_count / segs_per_sec) < total_sections) {
		f2fs_info(sbi, "Small segment_count (%u < %u * %u)",
			  segment_count, segs_per_sec, total_sections);
		return -EFSCORRUPTED;
	}

	if (segment_count > (le64_to_cpu(raw_super->block_count) >> 9)) {
		f2fs_info(sbi, "Wrong segment_count / block_count (%u > %llu)",
			  segment_count, le64_to_cpu(raw_super->block_count));
		return -EFSCORRUPTED;
	}

	if (RDEV(0).path[0]) {
		block_t dev_seg_count = le32_to_cpu(RDEV(0).total_segments);
		int i = 1;

		while (i < MAX_DEVICES && RDEV(i).path[0]) {
			dev_seg_count += le32_to_cpu(RDEV(i).total_segments);
			i++;
		}
		if (segment_count != dev_seg_count) {
			f2fs_info(sbi, "Segment count (%u) mismatch with total segments from devices (%u)",
					segment_count, dev_seg_count);
			return -EFSCORRUPTED;
		}
	} else {
		if (__F2FS_HAS_FEATURE(raw_super, F2FS_FEATURE_BLKZONED) &&
					!bdev_is_zoned(sbi->sb->s_bdev)) {
			f2fs_info(sbi, "Zoned block device path is missing");
			return -EFSCORRUPTED;
		}
	}

	if (secs_per_zone > total_sections || !secs_per_zone) {
		f2fs_info(sbi, "Wrong secs_per_zone / total_sections (%u, %u)",
			  secs_per_zone, total_sections);
		return -EFSCORRUPTED;
	}
	if (le32_to_cpu(raw_super->extension_count) > F2FS_MAX_EXTENSION ||
			raw_super->hot_ext_count > F2FS_MAX_EXTENSION ||
			(le32_to_cpu(raw_super->extension_count) +
			raw_super->hot_ext_count) > F2FS_MAX_EXTENSION) {
		f2fs_info(sbi, "Corrupted extension count (%u + %u > %u)",
			  le32_to_cpu(raw_super->extension_count),
			  raw_super->hot_ext_count,
			  F2FS_MAX_EXTENSION);
		return -EFSCORRUPTED;
	}

	if (le32_to_cpu(raw_super->cp_payload) >=
				(blocks_per_seg - F2FS_CP_PACKS -
				NR_CURSEG_PERSIST_TYPE)) {
		f2fs_info(sbi, "Insane cp_payload (%u >= %u)",
			  le32_to_cpu(raw_super->cp_payload),
			  blocks_per_seg - F2FS_CP_PACKS -
			  NR_CURSEG_PERSIST_TYPE);
		return -EFSCORRUPTED;
	}

	/* check reserved ino info */
	if (le32_to_cpu(raw_super->node_ino) != 1 ||
		le32_to_cpu(raw_super->meta_ino) != 2 ||
		le32_to_cpu(raw_super->root_ino) != 3) {
		f2fs_info(sbi, "Invalid Fs Meta Ino: node(%u) meta(%u) root(%u)",
			  le32_to_cpu(raw_super->node_ino),
			  le32_to_cpu(raw_super->meta_ino),
			  le32_to_cpu(raw_super->root_ino));
		return -EFSCORRUPTED;
	}

	/* check CP/SIT/NAT/SSA/MAIN_AREA area boundary */
	if (sanity_check_area_boundary(sbi, bh))
		return -EFSCORRUPTED;

	return 0;
}

int f2fs_sanity_check_ckpt(struct f2fs_sb_info *sbi)
{
	unsigned int total, fsmeta;
	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
	unsigned int ovp_segments, reserved_segments;
	unsigned int main_segs, blocks_per_seg;
	unsigned int sit_segs, nat_segs;
	unsigned int sit_bitmap_size, nat_bitmap_size;
	unsigned int log_blocks_per_seg;
	unsigned int segment_count_main;
	unsigned int cp_pack_start_sum, cp_payload;
	block_t user_block_count, valid_user_blocks;
	block_t avail_node_count, valid_node_count;
	unsigned int nat_blocks, nat_bits_bytes, nat_bits_blocks;
	int i, j;

	total = le32_to_cpu(raw_super->segment_count);
	fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
	sit_segs = le32_to_cpu(raw_super->segment_count_sit);
	fsmeta += sit_segs;
	nat_segs = le32_to_cpu(raw_super->segment_count_nat);
	fsmeta += nat_segs;
	fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
	fsmeta += le32_to_cpu(raw_super->segment_count_ssa);

	if (unlikely(fsmeta >= total))
		return 1;

	ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
	reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);

	if (!f2fs_sb_has_readonly(sbi) &&
			unlikely(fsmeta < F2FS_MIN_META_SEGMENTS ||
			ovp_segments == 0 || reserved_segments == 0)) {
		f2fs_err(sbi, "Wrong layout: check mkfs.f2fs version");
		return 1;
	}
	user_block_count = le64_to_cpu(ckpt->user_block_count);
	segment_count_main = le32_to_cpu(raw_super->segment_count_main) +
			(f2fs_sb_has_readonly(sbi) ? 1 : 0);
	log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
	if (!user_block_count || user_block_count >=
			segment_count_main << log_blocks_per_seg) {
		f2fs_err(sbi, "Wrong user_block_count: %u",
			 user_block_count);
		return 1;
	}

	valid_user_blocks = le64_to_cpu(ckpt->valid_block_count);
	if (valid_user_blocks > user_block_count) {
		f2fs_err(sbi, "Wrong valid_user_blocks: %u, user_block_count: %u",
			 valid_user_blocks, user_block_count);
		return 1;
	}

	valid_node_count = le32_to_cpu(ckpt->valid_node_count);
	avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
	if (valid_node_count > avail_node_count) {
		f2fs_err(sbi, "Wrong valid_node_count: %u, avail_node_count: %u",
			 valid_node_count, avail_node_count);
		return 1;
	}

	main_segs = le32_to_cpu(raw_super->segment_count_main);
	blocks_per_seg = sbi->blocks_per_seg;

	for (i = 0; i < NR_CURSEG_NODE_TYPE; i++) {
		if (le32_to_cpu(ckpt->cur_node_segno[i]) >= main_segs ||
			le16_to_cpu(ckpt->cur_node_blkoff[i]) >= blocks_per_seg)
			return 1;

		if (f2fs_sb_has_readonly(sbi))
			goto check_data;

		for (j = i + 1; j < NR_CURSEG_NODE_TYPE; j++) {
			if (le32_to_cpu(ckpt->cur_node_segno[i]) ==
				le32_to_cpu(ckpt->cur_node_segno[j])) {
				f2fs_err(sbi, "Node segment (%u, %u) has the same segno: %u",
					 i, j,
					 le32_to_cpu(ckpt->cur_node_segno[i]));
				return 1;
			}
		}
	}
check_data:
	for (i = 0; i < NR_CURSEG_DATA_TYPE; i++) {
		if (le32_to_cpu(ckpt->cur_data_segno[i]) >= main_segs ||
			le16_to_cpu(ckpt->cur_data_blkoff[i]) >= blocks_per_seg)
			return 1;

		if (f2fs_sb_has_readonly(sbi))
			goto skip_cross;

		for (j = i + 1; j < NR_CURSEG_DATA_TYPE; j++) {
			if (le32_to_cpu(ckpt->cur_data_segno[i]) ==
				le32_to_cpu(ckpt->cur_data_segno[j])) {
				f2fs_err(sbi, "Data segment (%u, %u) has the same segno: %u",
					 i, j,
					 le32_to_cpu(ckpt->cur_data_segno[i]));
				return 1;
			}
		}
	}
	for (i = 0; i < NR_CURSEG_NODE_TYPE; i++) {
		for (j = 0; j < NR_CURSEG_DATA_TYPE; j++) {
			if (le32_to_cpu(ckpt->cur_node_segno[i]) ==
				le32_to_cpu(ckpt->cur_data_segno[j])) {
				f2fs_err(sbi, "Node segment (%u) and Data segment (%u) has the same segno: %u",
					 i, j,
					 le32_to_cpu(ckpt->cur_node_segno[i]));
				return 1;
			}
		}
	}
skip_cross:
	sit_bitmap_size = le32_to_cpu(ckpt->sit_ver_bitmap_bytesize);
	nat_bitmap_size = le32_to_cpu(ckpt->nat_ver_bitmap_bytesize);

	if (sit_bitmap_size != ((sit_segs / 2) << log_blocks_per_seg) / 8 ||
		nat_bitmap_size != ((nat_segs / 2) << log_blocks_per_seg) / 8) {
		f2fs_err(sbi, "Wrong bitmap size: sit: %u, nat:%u",
			 sit_bitmap_size, nat_bitmap_size);
		return 1;
	}

	cp_pack_start_sum = __start_sum_addr(sbi);
	cp_payload = __cp_payload(sbi);
	if (cp_pack_start_sum < cp_payload + 1 ||
		cp_pack_start_sum > blocks_per_seg - 1 -
			NR_CURSEG_PERSIST_TYPE) {
		f2fs_err(sbi, "Wrong cp_pack_start_sum: %u",
			 cp_pack_start_sum);
		return 1;
	}

	if (__is_set_ckpt_flags(ckpt, CP_LARGE_NAT_BITMAP_FLAG) &&
		le32_to_cpu(ckpt->checksum_offset) != CP_MIN_CHKSUM_OFFSET) {
		f2fs_warn(sbi, "using deprecated layout of large_nat_bitmap, "
			  "please run fsck v1.13.0 or higher to repair, chksum_offset: %u, "
			  "fixed with patch: \"f2fs-tools: relocate chksum_offset for large_nat_bitmap feature\"",
			  le32_to_cpu(ckpt->checksum_offset));
		return 1;
	}

	nat_blocks = nat_segs << log_blocks_per_seg;
	nat_bits_bytes = nat_blocks / BITS_PER_BYTE;
	nat_bits_blocks = F2FS_BLK_ALIGN((nat_bits_bytes << 1) + 8);
	if (__is_set_ckpt_flags(ckpt, CP_NAT_BITS_FLAG) &&
		(cp_payload + F2FS_CP_PACKS +
		NR_CURSEG_PERSIST_TYPE + nat_bits_blocks >= blocks_per_seg)) {
		f2fs_warn(sbi, "Insane cp_payload: %u, nat_bits_blocks: %u)",
			  cp_payload, nat_bits_blocks);
		return 1;
	}

	if (unlikely(f2fs_cp_error(sbi))) {
		f2fs_err(sbi, "A bug case: need to run fsck");
		return 1;
	}
	return 0;
}

static void init_sb_info(struct f2fs_sb_info *sbi)
{
	struct f2fs_super_block *raw_super = sbi->raw_super;
	int i;

	sbi->log_sectors_per_block =
		le32_to_cpu(raw_super->log_sectors_per_block);
	sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
	sbi->blocksize = 1 << sbi->log_blocksize;
	sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
	sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
	sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
	sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
	sbi->total_sections = le32_to_cpu(raw_super->section_count);
	sbi->total_node_count =
		(le32_to_cpu(raw_super->segment_count_nat) / 2)
			* sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
	F2FS_ROOT_INO(sbi) = le32_to_cpu(raw_super->root_ino);
	F2FS_NODE_INO(sbi) = le32_to_cpu(raw_super->node_ino);
	F2FS_META_INO(sbi) = le32_to_cpu(raw_super->meta_ino);
	sbi->cur_victim_sec = NULL_SECNO;
	sbi->next_victim_seg[BG_GC] = NULL_SEGNO;
	sbi->next_victim_seg[FG_GC] = NULL_SEGNO;
	sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
	sbi->migration_granularity = sbi->segs_per_sec;
	sbi->seq_file_ra_mul = MIN_RA_MUL;

	sbi->dir_level = DEF_DIR_LEVEL;
	sbi->interval_time[CP_TIME] = DEF_CP_INTERVAL;
	sbi->interval_time[REQ_TIME] = DEF_IDLE_INTERVAL;
	sbi->interval_time[DISCARD_TIME] = DEF_IDLE_INTERVAL;
	sbi->interval_time[GC_TIME] = DEF_IDLE_INTERVAL;
	sbi->interval_time[DISABLE_TIME] = DEF_DISABLE_INTERVAL;
	sbi->interval_time[UMOUNT_DISCARD_TIMEOUT] =
				DEF_UMOUNT_DISCARD_TIMEOUT;
	clear_sbi_flag(sbi, SBI_NEED_FSCK);

	for (i = 0; i < NR_COUNT_TYPE; i++)
		atomic_set(&sbi->nr_pages[i], 0);

	for (i = 0; i < META; i++)
		atomic_set(&sbi->wb_sync_req[i], 0);

	INIT_LIST_HEAD(&sbi->s_list);
	mutex_init(&sbi->umount_mutex);
	init_rwsem(&sbi->io_order_lock);
	spin_lock_init(&sbi->cp_lock);

	sbi->dirty_device = 0;
	spin_lock_init(&sbi->dev_lock);

	init_rwsem(&sbi->sb_lock);
	init_rwsem(&sbi->pin_sem);
}

static int init_percpu_info(struct f2fs_sb_info *sbi)
{
	int err;

	err = percpu_counter_init(&sbi->alloc_valid_block_count, 0, GFP_KERNEL);
	if (err)
		return err;

	err = percpu_counter_init(&sbi->total_valid_inode_count, 0,
								GFP_KERNEL);
	if (err)
		percpu_counter_destroy(&sbi->alloc_valid_block_count);

	return err;
}

#ifdef CONFIG_BLK_DEV_ZONED

struct f2fs_report_zones_args {
	struct f2fs_sb_info *sbi;
	struct f2fs_dev_info *dev;
};

static int f2fs_report_zone_cb(struct blk_zone *zone, unsigned int idx,
			      void *data)
{
	struct f2fs_report_zones_args *rz_args = data;
	block_t unusable_blocks = (zone->len - zone->capacity) >>
					F2FS_LOG_SECTORS_PER_BLOCK;

	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
		return 0;

	set_bit(idx, rz_args->dev->blkz_seq);
	if (!rz_args->sbi->unusable_blocks_per_sec) {
		rz_args->sbi->unusable_blocks_per_sec = unusable_blocks;
		return 0;
	}
	if (rz_args->sbi->unusable_blocks_per_sec != unusable_blocks) {
		f2fs_err(rz_args->sbi, "F2FS supports single zone capacity\n");
		return -EINVAL;
	}
	return 0;
}

static int init_blkz_info(struct f2fs_sb_info *sbi, int devi)
{
	struct block_device *bdev = FDEV(devi).bdev;
	sector_t nr_sectors = bdev_nr_sectors(bdev);
	struct f2fs_report_zones_args rep_zone_arg;
	int ret;

	if (!f2fs_sb_has_blkzoned(sbi))
		return 0;

	if (sbi->blocks_per_blkz && sbi->blocks_per_blkz !=
				SECTOR_TO_BLOCK(bdev_zone_sectors(bdev)))
		return -EINVAL;
	sbi->blocks_per_blkz = SECTOR_TO_BLOCK(bdev_zone_sectors(bdev));
	if (sbi->log_blocks_per_blkz && sbi->log_blocks_per_blkz !=
				__ilog2_u32(sbi->blocks_per_blkz))
		return -EINVAL;
	sbi->log_blocks_per_blkz = __ilog2_u32(sbi->blocks_per_blkz);
	FDEV(devi).nr_blkz = SECTOR_TO_BLOCK(nr_sectors) >>
					sbi->log_blocks_per_blkz;
	if (nr_sectors & (bdev_zone_sectors(bdev) - 1))
		FDEV(devi).nr_blkz++;

	FDEV(devi).blkz_seq = f2fs_kvzalloc(sbi,
					BITS_TO_LONGS(FDEV(devi).nr_blkz)
					* sizeof(unsigned long),
					GFP_KERNEL);
	if (!FDEV(devi).blkz_seq)
		return -ENOMEM;

	rep_zone_arg.sbi = sbi;
	rep_zone_arg.dev = &FDEV(devi);

	ret = blkdev_report_zones(bdev, 0, BLK_ALL_ZONES, f2fs_report_zone_cb,
				  &rep_zone_arg);
	if (ret < 0)
		return ret;
	return 0;
}
#endif

/*
 * Read f2fs raw super block.
 * Because we have two copies of super block, so read both of them
 * to get the first valid one. If any one of them is broken, we pass
 * them recovery flag back to the caller.
 */
static int read_raw_super_block(struct f2fs_sb_info *sbi,
			struct f2fs_super_block **raw_super,
			int *valid_super_block, int *recovery)
{
	struct super_block *sb = sbi->sb;
	int block;
	struct buffer_head *bh;
	struct f2fs_super_block *super;
	int err = 0;

	super = kzalloc(sizeof(struct f2fs_super_block), GFP_KERNEL);
	if (!super)
		return -ENOMEM;

	for (block = 0; block < 2; block++) {
		bh = sb_bread(sb, block);
		if (!bh) {
			f2fs_err(sbi, "Unable to read %dth superblock",
				 block + 1);
			err = -EIO;
			*recovery = 1;
			continue;
		}

		/* sanity checking of raw super */
		err = sanity_check_raw_super(sbi, bh);
		if (err) {
			f2fs_err(sbi, "Can't find valid F2FS filesystem in %dth superblock",
				 block + 1);
			brelse(bh);
			*recovery = 1;
			continue;
		}

		if (!*raw_super) {
			memcpy(super, bh->b_data + F2FS_SUPER_OFFSET,
							sizeof(*super));
			*valid_super_block = block;
			*raw_super = super;
		}
		brelse(bh);
	}

	/* No valid superblock */
	if (!*raw_super)
		kfree(super);
	else
		err = 0;

	return err;
}

int f2fs_commit_super(struct f2fs_sb_info *sbi, bool recover)
{
	struct buffer_head *bh;
	__u32 crc = 0;
	int err;

	if ((recover && f2fs_readonly(sbi->sb)) ||
				bdev_read_only(sbi->sb->s_bdev)) {
		set_sbi_flag(sbi, SBI_NEED_SB_WRITE);
		return -EROFS;
	}

	/* we should update superblock crc here */
	if (!recover && f2fs_sb_has_sb_chksum(sbi)) {
		crc = f2fs_crc32(sbi, F2FS_RAW_SUPER(sbi),
				offsetof(struct f2fs_super_block, crc));
		F2FS_RAW_SUPER(sbi)->crc = cpu_to_le32(crc);
	}

	/* write back-up superblock first */
	bh = sb_bread(sbi->sb, sbi->valid_super_block ? 0 : 1);
	if (!bh)
		return -EIO;
	err = __f2fs_commit_super(bh, F2FS_RAW_SUPER(sbi));
	brelse(bh);

	/* if we are in recovery path, skip writing valid superblock */
	if (recover || err)
		return err;

	/* write current valid superblock */
	bh = sb_bread(sbi->sb, sbi->valid_super_block);
	if (!bh)
		return -EIO;
	err = __f2fs_commit_super(bh, F2FS_RAW_SUPER(sbi));
	brelse(bh);
	return err;
}

static int f2fs_scan_devices(struct f2fs_sb_info *sbi)
{
	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
	unsigned int max_devices = MAX_DEVICES;
	unsigned int logical_blksize;
	int i;

	/* Initialize single device information */
	if (!RDEV(0).path[0]) {
		if (!bdev_is_zoned(sbi->sb->s_bdev))
			return 0;
		max_devices = 1;
	}

	/*
	 * Initialize multiple devices information, or single
	 * zoned block device information.
	 */
	sbi->devs = f2fs_kzalloc(sbi,
				 array_size(max_devices,
					    sizeof(struct f2fs_dev_info)),
				 GFP_KERNEL);
	if (!sbi->devs)
		return -ENOMEM;

	logical_blksize = bdev_logical_block_size(sbi->sb->s_bdev);
	sbi->aligned_blksize = true;

	for (i = 0; i < max_devices; i++) {

		if (i > 0 && !RDEV(i).path[0])
			break;

		if (max_devices == 1) {
			/* Single zoned block device mount */
			FDEV(0).bdev =
				blkdev_get_by_dev(sbi->sb->s_bdev->bd_dev,
					sbi->sb->s_mode, sbi->sb->s_type);
		} else {
			/* Multi-device mount */
			memcpy(FDEV(i).path, RDEV(i).path, MAX_PATH_LEN);
			FDEV(i).total_segments =
				le32_to_cpu(RDEV(i).total_segments);
			if (i == 0) {
				FDEV(i).start_blk = 0;
				FDEV(i).end_blk = FDEV(i).start_blk +
				    (FDEV(i).total_segments <<
				    sbi->log_blocks_per_seg) - 1 +
				    le32_to_cpu(raw_super->segment0_blkaddr);
			} else {
				FDEV(i).start_blk = FDEV(i - 1).end_blk + 1;
				FDEV(i).end_blk = FDEV(i).start_blk +
					(FDEV(i).total_segments <<
					sbi->log_blocks_per_seg) - 1;
			}
			FDEV(i).bdev = blkdev_get_by_path(FDEV(i).path,
					sbi->sb->s_mode, sbi->sb->s_type);
		}
		if (IS_ERR(FDEV(i).bdev))
			return PTR_ERR(FDEV(i).bdev);

		/* to release errored devices */
		sbi->s_ndevs = i + 1;

		if (logical_blksize != bdev_logical_block_size(FDEV(i).bdev))
			sbi->aligned_blksize = false;

#ifdef CONFIG_BLK_DEV_ZONED
		if (bdev_zoned_model(FDEV(i).bdev) == BLK_ZONED_HM &&
				!f2fs_sb_has_blkzoned(sbi)) {
			f2fs_err(sbi, "Zoned block device feature not enabled");
			return -EINVAL;
		}
		if (bdev_zoned_model(FDEV(i).bdev) != BLK_ZONED_NONE) {
			if (init_blkz_info(sbi, i)) {
				f2fs_err(sbi, "Failed to initialize F2FS blkzone information");
				return -EINVAL;
			}
			if (max_devices == 1)
				break;
			f2fs_info(sbi, "Mount Device [%2d]: %20s, %8u, %8x - %8x (zone: %s)",
				  i, FDEV(i).path,
				  FDEV(i).total_segments,
				  FDEV(i).start_blk, FDEV(i).end_blk,
				  bdev_zoned_model(FDEV(i).bdev) == BLK_ZONED_HA ?
				  "Host-aware" : "Host-managed");
			continue;
		}
#endif
		f2fs_info(sbi, "Mount Device [%2d]: %20s, %8u, %8x - %8x",
			  i, FDEV(i).path,
			  FDEV(i).total_segments,
			  FDEV(i).start_blk, FDEV(i).end_blk);
	}
	f2fs_info(sbi,
		  "IO Block Size: %8d KB", F2FS_IO_SIZE_KB(sbi));
	return 0;
}

static int f2fs_setup_casefold(struct f2fs_sb_info *sbi)
{
#ifdef CONFIG_UNICODE
	if (f2fs_sb_has_casefold(sbi) && !sbi->sb->s_encoding) {
		const struct f2fs_sb_encodings *encoding_info;
		struct unicode_map *encoding;
		__u16 encoding_flags;

		if (f2fs_sb_read_encoding(sbi->raw_super, &encoding_info,
					  &encoding_flags)) {
			f2fs_err(sbi,
				 "Encoding requested by superblock is unknown");
			return -EINVAL;
		}

		encoding = utf8_load(encoding_info->version);
		if (IS_ERR(encoding)) {
			f2fs_err(sbi,
				 "can't mount with superblock charset: %s-%s "
				 "not supported by the kernel. flags: 0x%x.",
				 encoding_info->name, encoding_info->version,
				 encoding_flags);
			return PTR_ERR(encoding);
		}
		f2fs_info(sbi, "Using encoding defined by superblock: "
			 "%s-%s with flags 0x%hx", encoding_info->name,
			 encoding_info->version?:"\b", encoding_flags);

		sbi->sb->s_encoding = encoding;
		sbi->sb->s_encoding_flags = encoding_flags;
	}
#else
	if (f2fs_sb_has_casefold(sbi)) {
		f2fs_err(sbi, "Filesystem with casefold feature cannot be mounted without CONFIG_UNICODE");
		return -EINVAL;
	}
#endif
	return 0;
}

static void f2fs_tuning_parameters(struct f2fs_sb_info *sbi)
{
	struct f2fs_sm_info *sm_i = SM_I(sbi);

	/* adjust parameters according to the volume size */
	if (sm_i->main_segments <= SMALL_VOLUME_SEGMENTS) {
		F2FS_OPTION(sbi).alloc_mode = ALLOC_MODE_REUSE;
		if (f2fs_block_unit_discard(sbi))
			sm_i->dcc_info->discard_granularity = 1;
		sm_i->ipu_policy = 1 << F2FS_IPU_FORCE;
	}

	sbi->readdir_ra = 1;
}

static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
{
	struct f2fs_sb_info *sbi;
	struct f2fs_super_block *raw_super;
	struct inode *root;
	int err;
	bool skip_recovery = false, need_fsck = false;
	char *options = NULL;
	int recovery, i, valid_super_block;
	struct curseg_info *seg_i;
	int retry_cnt = 1;

try_onemore:
	err = -EINVAL;
	raw_super = NULL;
	valid_super_block = -1;
	recovery = 0;

	/* allocate memory for f2fs-specific super block info */
	sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
	if (!sbi)
		return -ENOMEM;

	sbi->sb = sb;

	/* Load the checksum driver */
	sbi->s_chksum_driver = crypto_alloc_shash("crc32", 0, 0);
	if (IS_ERR(sbi->s_chksum_driver)) {
		f2fs_err(sbi, "Cannot load crc32 driver.");
		err = PTR_ERR(sbi->s_chksum_driver);
		sbi->s_chksum_driver = NULL;
		goto free_sbi;
	}

	/* set a block size */
	if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
		f2fs_err(sbi, "unable to set blocksize");
		goto free_sbi;
	}

	err = read_raw_super_block(sbi, &raw_super, &valid_super_block,
								&recovery);
	if (err)
		goto free_sbi;

	sb->s_fs_info = sbi;
	sbi->raw_super = raw_super;

	/* precompute checksum seed for metadata */
	if (f2fs_sb_has_inode_chksum(sbi))
		sbi->s_chksum_seed = f2fs_chksum(sbi, ~0, raw_super->uuid,
						sizeof(raw_super->uuid));

	default_options(sbi);
	/* parse mount options */
	options = kstrdup((const char *)data, GFP_KERNEL);
	if (data && !options) {
		err = -ENOMEM;
		goto free_sb_buf;
	}

	err = parse_options(sb, options, false);
	if (err)
		goto free_options;

	sb->s_maxbytes = max_file_blocks(NULL) <<
				le32_to_cpu(raw_super->log_blocksize);
	sb->s_max_links = F2FS_LINK_MAX;

	err = f2fs_setup_casefold(sbi);
	if (err)
		goto free_options;

#ifdef CONFIG_QUOTA
	sb->dq_op = &f2fs_quota_operations;
	sb->s_qcop = &f2fs_quotactl_ops;
	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;

	if (f2fs_sb_has_quota_ino(sbi)) {
		for (i = 0; i < MAXQUOTAS; i++) {
			if (f2fs_qf_ino(sbi->sb, i))
				sbi->nquota_files++;
		}
	}
#endif

	sb->s_op = &f2fs_sops;
#ifdef CONFIG_FS_ENCRYPTION
	sb->s_cop = &f2fs_cryptops;
#endif
#ifdef CONFIG_FS_VERITY
	sb->s_vop = &f2fs_verityops;
#endif
	sb->s_xattr = f2fs_xattr_handlers;
	sb->s_export_op = &f2fs_export_ops;
	sb->s_magic = F2FS_SUPER_MAGIC;
	sb->s_time_gran = 1;
	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
		(test_opt(sbi, POSIX_ACL) ? SB_POSIXACL : 0);
	memcpy(&sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
	sb->s_iflags |= SB_I_CGROUPWB;

	/* init f2fs-specific super block info */
	sbi->valid_super_block = valid_super_block;
	init_rwsem(&sbi->gc_lock);
	mutex_init(&sbi->writepages);
	init_rwsem(&sbi->cp_global_sem);
	init_rwsem(&sbi->node_write);
	init_rwsem(&sbi->node_change);

	/* disallow all the data/node/meta page writes */
	set_sbi_flag(sbi, SBI_POR_DOING);
	spin_lock_init(&sbi->stat_lock);

	for (i = 0; i < NR_PAGE_TYPE; i++) {
		int n = (i == META) ? 1 : NR_TEMP_TYPE;
		int j;

		sbi->write_io[i] =
			f2fs_kmalloc(sbi,
				     array_size(n,
						sizeof(struct f2fs_bio_info)),
				     GFP_KERNEL);
		if (!sbi->write_io[i]) {
			err = -ENOMEM;
			goto free_bio_info;
		}

		for (j = HOT; j < n; j++) {
			init_rwsem(&sbi->write_io[i][j].io_rwsem);
			sbi->write_io[i][j].sbi = sbi;
			sbi->write_io[i][j].bio = NULL;
			spin_lock_init(&sbi->write_io[i][j].io_lock);
			INIT_LIST_HEAD(&sbi->write_io[i][j].io_list);
			INIT_LIST_HEAD(&sbi->write_io[i][j].bio_list);
			init_rwsem(&sbi->write_io[i][j].bio_list_lock);
		}
	}

	init_rwsem(&sbi->cp_rwsem);
	init_rwsem(&sbi->quota_sem);
	init_waitqueue_head(&sbi->cp_wait);
	init_sb_info(sbi);

	err = f2fs_init_iostat(sbi);
	if (err)
		goto free_bio_info;

	err = init_percpu_info(sbi);
	if (err)
		goto free_iostat;

	if (F2FS_IO_ALIGNED(sbi)) {
		sbi->write_io_dummy =
			mempool_create_page_pool(2 * (F2FS_IO_SIZE(sbi) - 1), 0);
		if (!sbi->write_io_dummy) {
			err = -ENOMEM;
			goto free_percpu;
		}
	}

	/* init per sbi slab cache */
	err = f2fs_init_xattr_caches(sbi);
	if (err)
		goto free_io_dummy;
	err = f2fs_init_page_array_cache(sbi);
	if (err)
		goto free_xattr_cache;

	/* get an inode for meta space */
	sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
	if (IS_ERR(sbi->meta_inode)) {
		f2fs_err(sbi, "Failed to read F2FS meta data inode");
		err = PTR_ERR(sbi->meta_inode);
		goto free_page_array_cache;
	}

	err = f2fs_get_valid_checkpoint(sbi);
	if (err) {
		f2fs_err(sbi, "Failed to get valid F2FS checkpoint");
		goto free_meta_inode;
	}

	if (__is_set_ckpt_flags(F2FS_CKPT(sbi), CP_QUOTA_NEED_FSCK_FLAG))
		set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
	if (__is_set_ckpt_flags(F2FS_CKPT(sbi), CP_DISABLED_QUICK_FLAG)) {
		set_sbi_flag(sbi, SBI_CP_DISABLED_QUICK);
		sbi->interval_time[DISABLE_TIME] = DEF_DISABLE_QUICK_INTERVAL;
	}

	if (__is_set_ckpt_flags(F2FS_CKPT(sbi), CP_FSCK_FLAG))
		set_sbi_flag(sbi, SBI_NEED_FSCK);

	/* Initialize device list */
	err = f2fs_scan_devices(sbi);
	if (err) {
		f2fs_err(sbi, "Failed to find devices");
		goto free_devices;
	}

	err = f2fs_init_post_read_wq(sbi);
	if (err) {
		f2fs_err(sbi, "Failed to initialize post read workqueue");
		goto free_devices;
	}

	sbi->total_valid_node_count =
				le32_to_cpu(sbi->ckpt->valid_node_count);
	percpu_counter_set(&sbi->total_valid_inode_count,
				le32_to_cpu(sbi->ckpt->valid_inode_count));
	sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
	sbi->total_valid_block_count =
				le64_to_cpu(sbi->ckpt->valid_block_count);
	sbi->last_valid_block_count = sbi->total_valid_block_count;
	sbi->reserved_blocks = 0;
	sbi->current_reserved_blocks = 0;
	limit_reserve_root(sbi);
	adjust_unusable_cap_perc(sbi);

	for (i = 0; i < NR_INODE_TYPE; i++) {
		INIT_LIST_HEAD(&sbi->inode_list[i]);
		spin_lock_init(&sbi->inode_lock[i]);
	}
	mutex_init(&sbi->flush_lock);

	f2fs_init_extent_cache_info(sbi);

	f2fs_init_ino_entry_info(sbi);

	f2fs_init_fsync_node_info(sbi);

	/* setup checkpoint request control and start checkpoint issue thread */
	f2fs_init_ckpt_req_control(sbi);
	if (!f2fs_readonly(sb) && !test_opt(sbi, DISABLE_CHECKPOINT) &&
			test_opt(sbi, MERGE_CHECKPOINT)) {
		err = f2fs_start_ckpt_thread(sbi);
		if (err) {
			f2fs_err(sbi,
			    "Failed to start F2FS issue_checkpoint_thread (%d)",
			    err);
			goto stop_ckpt_thread;
		}
	}

	/* setup f2fs internal modules */
	err = f2fs_build_segment_manager(sbi);
	if (err) {
		f2fs_err(sbi, "Failed to initialize F2FS segment manager (%d)",
			 err);
		goto free_sm;
	}
	err = f2fs_build_node_manager(sbi);
	if (err) {
		f2fs_err(sbi, "Failed to initialize F2FS node manager (%d)",
			 err);
		goto free_nm;
	}

	err = adjust_reserved_segment(sbi);
	if (err)
		goto free_nm;

	/* For write statistics */
	sbi->sectors_written_start = f2fs_get_sectors_written(sbi);

	/* Read accumulated write IO statistics if exists */
	seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
	if (__exist_node_summaries(sbi))
		sbi->kbytes_written =
			le64_to_cpu(seg_i->journal->info.kbytes_written);

	f2fs_build_gc_manager(sbi);

	err = f2fs_build_stats(sbi);
	if (err)
		goto free_nm;

	/* get an inode for node space */
	sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
	if (IS_ERR(sbi->node_inode)) {
		f2fs_err(sbi, "Failed to read node inode");
		err = PTR_ERR(sbi->node_inode);
		goto free_stats;
	}

	/* read root inode and dentry */
	root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
	if (IS_ERR(root)) {
		f2fs_err(sbi, "Failed to read root inode");
		err = PTR_ERR(root);
		goto free_node_inode;
	}
	if (!S_ISDIR(root->i_mode) || !root->i_blocks ||
			!root->i_size || !root->i_nlink) {
		iput(root);
		err = -EINVAL;
		goto free_node_inode;
	}

	sb->s_root = d_make_root(root); /* allocate root dentry */
	if (!sb->s_root) {
		err = -ENOMEM;
		goto free_node_inode;
	}

	err = f2fs_init_compress_inode(sbi);
	if (err)
		goto free_root_inode;

	err = f2fs_register_sysfs(sbi);
	if (err)
		goto free_compress_inode;

#ifdef CONFIG_QUOTA
	/* Enable quota usage during mount */
	if (f2fs_sb_has_quota_ino(sbi) && !f2fs_readonly(sb)) {
		err = f2fs_enable_quotas(sb);
		if (err)
			f2fs_err(sbi, "Cannot turn on quotas: error %d", err);
	}
#endif
	/* if there are any orphan inodes, free them */
	err = f2fs_recover_orphan_inodes(sbi);
	if (err)
		goto free_meta;

	if (unlikely(is_set_ckpt_flags(sbi, CP_DISABLED_FLAG)))
		goto reset_checkpoint;

	/* recover fsynced data */
	if (!test_opt(sbi, DISABLE_ROLL_FORWARD) &&
			!test_opt(sbi, NORECOVERY)) {
		/*
		 * mount should be failed, when device has readonly mode, and
		 * previous checkpoint was not done by clean system shutdown.
		 */
		if (f2fs_hw_is_readonly(sbi)) {
			if (!is_set_ckpt_flags(sbi, CP_UMOUNT_FLAG)) {
				err = f2fs_recover_fsync_data(sbi, true);
				if (err > 0) {
					err = -EROFS;
					f2fs_err(sbi, "Need to recover fsync data, but "
						"write access unavailable, please try "
						"mount w/ disable_roll_forward or norecovery");
				}
				if (err < 0)
					goto free_meta;
			}
			f2fs_info(sbi, "write access unavailable, skipping recovery");
			goto reset_checkpoint;
		}

		if (need_fsck)
			set_sbi_flag(sbi, SBI_NEED_FSCK);

		if (skip_recovery)
			goto reset_checkpoint;

		err = f2fs_recover_fsync_data(sbi, false);
		if (err < 0) {
			if (err != -ENOMEM)
				skip_recovery = true;
			need_fsck = true;
			f2fs_err(sbi, "Cannot recover all fsync data errno=%d",
				 err);
			goto free_meta;
		}
	} else {
		err = f2fs_recover_fsync_data(sbi, true);

		if (!f2fs_readonly(sb) && err > 0) {
			err = -EINVAL;
			f2fs_err(sbi, "Need to recover fsync data");
			goto free_meta;
		}
	}

	/*
	 * If the f2fs is not readonly and fsync data recovery succeeds,
	 * check zoned block devices' write pointer consistency.
	 */
	if (!err && !f2fs_readonly(sb) && f2fs_sb_has_blkzoned(sbi)) {
		err = f2fs_check_write_pointer(sbi);
		if (err)
			goto free_meta;
	}

reset_checkpoint:
	f2fs_init_inmem_curseg(sbi);

	/* f2fs_recover_fsync_data() cleared this already */
	clear_sbi_flag(sbi, SBI_POR_DOING);

	if (test_opt(sbi, DISABLE_CHECKPOINT)) {
		err = f2fs_disable_checkpoint(sbi);
		if (err)
			goto sync_free_meta;
	} else if (is_set_ckpt_flags(sbi, CP_DISABLED_FLAG)) {
		f2fs_enable_checkpoint(sbi);
	}

	/*
	 * If filesystem is not mounted as read-only then
	 * do start the gc_thread.
	 */
	if ((F2FS_OPTION(sbi).bggc_mode != BGGC_MODE_OFF ||
		test_opt(sbi, GC_MERGE)) && !f2fs_readonly(sb)) {
		/* After POR, we can run background GC thread.*/
		err = f2fs_start_gc_thread(sbi);
		if (err)
			goto sync_free_meta;
	}
	kvfree(options);

	/* recover broken superblock */
	if (recovery) {
		err = f2fs_commit_super(sbi, true);
		f2fs_info(sbi, "Try to recover %dth superblock, ret: %d",
			  sbi->valid_super_block ? 1 : 2, err);
	}

	f2fs_join_shrinker(sbi);

	f2fs_tuning_parameters(sbi);

	f2fs_notice(sbi, "Mounted with checkpoint version = %llx",
		    cur_cp_version(F2FS_CKPT(sbi)));
	f2fs_update_time(sbi, CP_TIME);
	f2fs_update_time(sbi, REQ_TIME);
	clear_sbi_flag(sbi, SBI_CP_DISABLED_QUICK);
	return 0;

sync_free_meta:
	/* safe to flush all the data */
	sync_filesystem(sbi->sb);
	retry_cnt = 0;

free_meta:
#ifdef CONFIG_QUOTA
	f2fs_truncate_quota_inode_pages(sb);
	if (f2fs_sb_has_quota_ino(sbi) && !f2fs_readonly(sb))
		f2fs_quota_off_umount(sbi->sb);
#endif
	/*
	 * Some dirty meta pages can be produced by f2fs_recover_orphan_inodes()
	 * failed by EIO. Then, iput(node_inode) can trigger balance_fs_bg()
	 * followed by f2fs_write_checkpoint() through f2fs_write_node_pages(), which
	 * falls into an infinite loop in f2fs_sync_meta_pages().
	 */
	truncate_inode_pages_final(META_MAPPING(sbi));
	/* evict some inodes being cached by GC */
	evict_inodes(sb);
	f2fs_unregister_sysfs(sbi);
free_compress_inode:
	f2fs_destroy_compress_inode(sbi);
free_root_inode:
	dput(sb->s_root);
	sb->s_root = NULL;
free_node_inode:
	f2fs_release_ino_entry(sbi, true);
	truncate_inode_pages_final(NODE_MAPPING(sbi));
	iput(sbi->node_inode);
	sbi->node_inode = NULL;
free_stats:
	f2fs_destroy_stats(sbi);
free_nm:
	/* stop discard thread before destroying node manager */
	f2fs_stop_discard_thread(sbi);
	f2fs_destroy_node_manager(sbi);
free_sm:
	f2fs_destroy_segment_manager(sbi);
stop_ckpt_thread:
	f2fs_stop_ckpt_thread(sbi);
	f2fs_destroy_post_read_wq(sbi);
free_devices:
	destroy_device_list(sbi);
	kvfree(sbi->ckpt);
free_meta_inode:
	make_bad_inode(sbi->meta_inode);
	iput(sbi->meta_inode);
	sbi->meta_inode = NULL;
free_page_array_cache:
	f2fs_destroy_page_array_cache(sbi);
free_xattr_cache:
	f2fs_destroy_xattr_caches(sbi);
free_io_dummy:
	mempool_destroy(sbi->write_io_dummy);
free_percpu:
	destroy_percpu_info(sbi);
free_iostat:
	f2fs_destroy_iostat(sbi);
free_bio_info:
	for (i = 0; i < NR_PAGE_TYPE; i++)
		kvfree(sbi->write_io[i]);

#ifdef CONFIG_UNICODE
	utf8_unload(sb->s_encoding);
	sb->s_encoding = NULL;
#endif
free_options:
#ifdef CONFIG_QUOTA
	for (i = 0; i < MAXQUOTAS; i++)
		kfree(F2FS_OPTION(sbi).s_qf_names[i]);
#endif
	fscrypt_free_dummy_policy(&F2FS_OPTION(sbi).dummy_enc_policy);
	kvfree(options);
free_sb_buf:
	kfree(raw_super);
free_sbi:
	if (sbi->s_chksum_driver)
		crypto_free_shash(sbi->s_chksum_driver);
	kfree(sbi);

	/* give only one another chance */
	if (retry_cnt > 0 && skip_recovery) {
		retry_cnt--;
		shrink_dcache_sb(sb);
		goto try_onemore;
	}
	return err;
}

static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
			const char *dev_name, void *data)
{
	return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
}

static void kill_f2fs_super(struct super_block *sb)
{
	if (sb->s_root) {
		struct f2fs_sb_info *sbi = F2FS_SB(sb);

		set_sbi_flag(sbi, SBI_IS_CLOSE);
		f2fs_stop_gc_thread(sbi);
		f2fs_stop_discard_thread(sbi);

#ifdef CONFIG_F2FS_FS_COMPRESSION
		/*
		 * latter evict_inode() can bypass checking and invalidating
		 * compress inode cache.
		 */
		if (test_opt(sbi, COMPRESS_CACHE))
			truncate_inode_pages_final(COMPRESS_MAPPING(sbi));
#endif

		if (is_sbi_flag_set(sbi, SBI_IS_DIRTY) ||
				!is_set_ckpt_flags(sbi, CP_UMOUNT_FLAG)) {
			struct cp_control cpc = {
				.reason = CP_UMOUNT,
			};
			f2fs_write_checkpoint(sbi, &cpc);
		}

		if (is_sbi_flag_set(sbi, SBI_IS_RECOVERED) && f2fs_readonly(sb))
			sb->s_flags &= ~SB_RDONLY;
	}
	kill_block_super(sb);
}

static struct file_system_type f2fs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "f2fs",
	.mount		= f2fs_mount,
	.kill_sb	= kill_f2fs_super,
	.fs_flags	= FS_REQUIRES_DEV,
};
MODULE_ALIAS_FS("f2fs");

static int __init init_inodecache(void)
{
	f2fs_inode_cachep = kmem_cache_create("f2fs_inode_cache",
			sizeof(struct f2fs_inode_info), 0,
			SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT, NULL);
	if (!f2fs_inode_cachep)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	/*
	 * Make sure all delayed rcu free inodes are flushed before we
	 * destroy cache.
	 */
	rcu_barrier();
	kmem_cache_destroy(f2fs_inode_cachep);
}

static int __init init_f2fs_fs(void)
{
	int err;

	if (PAGE_SIZE != F2FS_BLKSIZE) {
		printk("F2FS not supported on PAGE_SIZE(%lu) != %d\n",
				PAGE_SIZE, F2FS_BLKSIZE);
		return -EINVAL;
	}

	err = init_inodecache();
	if (err)
		goto fail;
	err = f2fs_create_node_manager_caches();
	if (err)
		goto free_inodecache;
	err = f2fs_create_segment_manager_caches();
	if (err)
		goto free_node_manager_caches;
	err = f2fs_create_checkpoint_caches();
	if (err)
		goto free_segment_manager_caches;
	err = f2fs_create_recovery_cache();
	if (err)
		goto free_checkpoint_caches;
	err = f2fs_create_extent_cache();
	if (err)
		goto free_recovery_cache;
	err = f2fs_create_garbage_collection_cache();
	if (err)
		goto free_extent_cache;
	err = f2fs_init_sysfs();
	if (err)
		goto free_garbage_collection_cache;
	err = register_shrinker(&f2fs_shrinker_info);
	if (err)
		goto free_sysfs;
	err = register_filesystem(&f2fs_fs_type);
	if (err)
		goto free_shrinker;
	f2fs_create_root_stats();
	err = f2fs_init_post_read_processing();
	if (err)
		goto free_root_stats;
	err = f2fs_init_iostat_processing();
	if (err)
		goto free_post_read;
	err = f2fs_init_bio_entry_cache();
	if (err)
		goto free_iostat;
	err = f2fs_init_bioset();
	if (err)
		goto free_bio_enrty_cache;
	err = f2fs_init_compress_mempool();
	if (err)
		goto free_bioset;
	err = f2fs_init_compress_cache();
	if (err)
		goto free_compress_mempool;
	err = f2fs_create_casefold_cache();
	if (err)
		goto free_compress_cache;
	return 0;
free_compress_cache:
	f2fs_destroy_compress_cache();
free_compress_mempool:
	f2fs_destroy_compress_mempool();
free_bioset:
	f2fs_destroy_bioset();
free_bio_enrty_cache:
	f2fs_destroy_bio_entry_cache();
free_iostat:
	f2fs_destroy_iostat_processing();
free_post_read:
	f2fs_destroy_post_read_processing();
free_root_stats:
	f2fs_destroy_root_stats();
	unregister_filesystem(&f2fs_fs_type);
free_shrinker:
	unregister_shrinker(&f2fs_shrinker_info);
free_sysfs:
	f2fs_exit_sysfs();
free_garbage_collection_cache:
	f2fs_destroy_garbage_collection_cache();
free_extent_cache:
	f2fs_destroy_extent_cache();
free_recovery_cache:
	f2fs_destroy_recovery_cache();
free_checkpoint_caches:
	f2fs_destroy_checkpoint_caches();
free_segment_manager_caches:
	f2fs_destroy_segment_manager_caches();
free_node_manager_caches:
	f2fs_destroy_node_manager_caches();
free_inodecache:
	destroy_inodecache();
fail:
	return err;
}

static void __exit exit_f2fs_fs(void)
{
	f2fs_destroy_casefold_cache();
	f2fs_destroy_compress_cache();
	f2fs_destroy_compress_mempool();
	f2fs_destroy_bioset();
	f2fs_destroy_bio_entry_cache();
	f2fs_destroy_iostat_processing();
	f2fs_destroy_post_read_processing();
	f2fs_destroy_root_stats();
	unregister_filesystem(&f2fs_fs_type);
	unregister_shrinker(&f2fs_shrinker_info);
	f2fs_exit_sysfs();
	f2fs_destroy_garbage_collection_cache();
	f2fs_destroy_extent_cache();
	f2fs_destroy_recovery_cache();
	f2fs_destroy_checkpoint_caches();
	f2fs_destroy_segment_manager_caches();
	f2fs_destroy_node_manager_caches();
	destroy_inodecache();
}

module_init(init_f2fs_fs)
module_exit(exit_f2fs_fs)

MODULE_AUTHOR("Samsung Electronics's Praesto Team");
MODULE_DESCRIPTION("Flash Friendly File System");
MODULE_LICENSE("GPL");
MODULE_SOFTDEP("pre: crc32");