linux_dsm_epyc7002/fs/f2fs/super.c
Namjae Jeon a2a4a7e4ab f2fs: add tracepoints for sync & inode operations
Add tracepoints in f2fs for tracing the syncing
operations like filesystem sync, file sync enter/exit.
It will helf to trace the code under debugging scenarios.

Also add tracepoints for tracing the various inode operations
like building inode, eviction of inode, link/unlike of
inodes.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-23 15:30:27 +09:00

778 lines
19 KiB
C

/*
* fs/f2fs/super.c
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/statfs.h>
#include <linux/proc_fs.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/random.h>
#include <linux/exportfs.h>
#include <linux/blkdev.h>
#include <linux/f2fs_fs.h>
#include "f2fs.h"
#include "node.h"
#include "segment.h"
#include "xattr.h"
#define CREATE_TRACE_POINTS
#include <trace/events/f2fs.h>
static struct kmem_cache *f2fs_inode_cachep;
enum {
Opt_gc_background_off,
Opt_disable_roll_forward,
Opt_discard,
Opt_noheap,
Opt_nouser_xattr,
Opt_noacl,
Opt_active_logs,
Opt_disable_ext_identify,
Opt_err,
};
static match_table_t f2fs_tokens = {
{Opt_gc_background_off, "background_gc_off"},
{Opt_disable_roll_forward, "disable_roll_forward"},
{Opt_discard, "discard"},
{Opt_noheap, "no_heap"},
{Opt_nouser_xattr, "nouser_xattr"},
{Opt_noacl, "noacl"},
{Opt_active_logs, "active_logs=%u"},
{Opt_disable_ext_identify, "disable_ext_identify"},
{Opt_err, NULL},
};
void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
{
struct va_format vaf;
va_list args;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
va_end(args);
}
static void init_once(void *foo)
{
struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
inode_init_once(&fi->vfs_inode);
}
static struct inode *f2fs_alloc_inode(struct super_block *sb)
{
struct f2fs_inode_info *fi;
fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_NOFS | __GFP_ZERO);
if (!fi)
return NULL;
init_once((void *) fi);
/* Initialize f2fs-specific inode info */
fi->vfs_inode.i_version = 1;
atomic_set(&fi->dirty_dents, 0);
fi->i_current_depth = 1;
fi->i_advise = 0;
rwlock_init(&fi->ext.ext_lock);
set_inode_flag(fi, FI_NEW_INODE);
return &fi->vfs_inode;
}
static void f2fs_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
}
static void f2fs_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, f2fs_i_callback);
}
static void f2fs_put_super(struct super_block *sb)
{
struct f2fs_sb_info *sbi = F2FS_SB(sb);
f2fs_destroy_stats(sbi);
stop_gc_thread(sbi);
write_checkpoint(sbi, true);
iput(sbi->node_inode);
iput(sbi->meta_inode);
/* destroy f2fs internal modules */
destroy_node_manager(sbi);
destroy_segment_manager(sbi);
kfree(sbi->ckpt);
sb->s_fs_info = NULL;
brelse(sbi->raw_super_buf);
kfree(sbi);
}
int f2fs_sync_fs(struct super_block *sb, int sync)
{
struct f2fs_sb_info *sbi = F2FS_SB(sb);
trace_f2fs_sync_fs(sb, sync);
if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
return 0;
if (sync) {
mutex_lock(&sbi->gc_mutex);
write_checkpoint(sbi, false);
mutex_unlock(&sbi->gc_mutex);
} else {
f2fs_balance_fs(sbi);
}
return 0;
}
static int f2fs_freeze(struct super_block *sb)
{
int err;
if (sb->s_flags & MS_RDONLY)
return 0;
err = f2fs_sync_fs(sb, 1);
return err;
}
static int f2fs_unfreeze(struct super_block *sb)
{
return 0;
}
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, ovp_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);
ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
buf->f_type = F2FS_SUPER_MAGIC;
buf->f_bsize = sbi->blocksize;
buf->f_blocks = total_count - start_count;
buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
buf->f_bavail = user_block_count - valid_user_blocks(sbi);
buf->f_files = sbi->total_node_count;
buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
buf->f_namelen = F2FS_NAME_LEN;
buf->f_fsid.val[0] = (u32)id;
buf->f_fsid.val[1] = (u32)(id >> 32);
return 0;
}
static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
{
struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
if (test_opt(sbi, BG_GC))
seq_puts(seq, ",background_gc_on");
else
seq_puts(seq, ",background_gc_off");
if (test_opt(sbi, DISABLE_ROLL_FORWARD))
seq_puts(seq, ",disable_roll_forward");
if (test_opt(sbi, DISCARD))
seq_puts(seq, ",discard");
if (test_opt(sbi, NOHEAP))
seq_puts(seq, ",no_heap_alloc");
#ifdef CONFIG_F2FS_FS_XATTR
if (test_opt(sbi, XATTR_USER))
seq_puts(seq, ",user_xattr");
else
seq_puts(seq, ",nouser_xattr");
#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");
seq_printf(seq, ",active_logs=%u", sbi->active_logs);
return 0;
}
static struct super_operations f2fs_sops = {
.alloc_inode = f2fs_alloc_inode,
.destroy_inode = f2fs_destroy_inode,
.write_inode = f2fs_write_inode,
.show_options = f2fs_show_options,
.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,
};
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 (ino < F2FS_ROOT_INO(sbi))
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 (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,
};
static int parse_options(struct super_block *sb, struct f2fs_sb_info *sbi,
char *options)
{
substring_t args[MAX_OPT_ARGS];
char *p;
int arg = 0;
if (!options)
return 0;
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_off:
clear_opt(sbi, BG_GC);
break;
case Opt_disable_roll_forward:
set_opt(sbi, DISABLE_ROLL_FORWARD);
break;
case Opt_discard:
set_opt(sbi, DISCARD);
break;
case Opt_noheap:
set_opt(sbi, NOHEAP);
break;
#ifdef CONFIG_F2FS_FS_XATTR
case Opt_nouser_xattr:
clear_opt(sbi, XATTR_USER);
break;
#else
case Opt_nouser_xattr:
f2fs_msg(sb, KERN_INFO,
"nouser_xattr options not supported");
break;
#endif
#ifdef CONFIG_F2FS_FS_POSIX_ACL
case Opt_noacl:
clear_opt(sbi, POSIX_ACL);
break;
#else
case Opt_noacl:
f2fs_msg(sb, KERN_INFO, "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_TYPE)
return -EINVAL;
sbi->active_logs = arg;
break;
case Opt_disable_ext_identify:
set_opt(sbi, DISABLE_EXT_IDENTIFY);
break;
default:
f2fs_msg(sb, KERN_ERR,
"Unrecognized mount option \"%s\" or missing value",
p);
return -EINVAL;
}
}
return 0;
}
static loff_t max_file_size(unsigned bits)
{
loff_t result = ADDRS_PER_INODE;
loff_t leaf_count = 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;
result <<= bits;
return result;
}
static int sanity_check_raw_super(struct super_block *sb,
struct f2fs_super_block *raw_super)
{
unsigned int blocksize;
if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
f2fs_msg(sb, KERN_INFO,
"Magic Mismatch, valid(0x%x) - read(0x%x)",
F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
return 1;
}
/* Currently, support only 4KB page cache size */
if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
f2fs_msg(sb, KERN_INFO,
"Invalid page_cache_size (%lu), supports only 4KB\n",
PAGE_CACHE_SIZE);
return 1;
}
/* Currently, support only 4KB block size */
blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
if (blocksize != F2FS_BLKSIZE) {
f2fs_msg(sb, KERN_INFO,
"Invalid blocksize (%u), supports only 4KB\n",
blocksize);
return 1;
}
if (le32_to_cpu(raw_super->log_sectorsize) !=
F2FS_LOG_SECTOR_SIZE) {
f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
return 1;
}
if (le32_to_cpu(raw_super->log_sectors_per_block) !=
F2FS_LOG_SECTORS_PER_BLOCK) {
f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
return 1;
}
return 0;
}
static int 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);
total = le32_to_cpu(raw_super->segment_count);
fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
fsmeta += le32_to_cpu(raw_super->segment_count_sit);
fsmeta += le32_to_cpu(raw_super->segment_count_nat);
fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
if (fsmeta >= total)
return 1;
if (is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) {
f2fs_msg(sbi->sb, KERN_ERR, "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;
sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
sbi->cur_victim_sec = NULL_SECNO;
for (i = 0; i < NR_COUNT_TYPE; i++)
atomic_set(&sbi->nr_pages[i], 0);
}
static int validate_superblock(struct super_block *sb,
struct f2fs_super_block **raw_super,
struct buffer_head **raw_super_buf, sector_t block)
{
const char *super = (block == 0 ? "first" : "second");
/* read f2fs raw super block */
*raw_super_buf = sb_bread(sb, block);
if (!*raw_super_buf) {
f2fs_msg(sb, KERN_ERR, "unable to read %s superblock",
super);
return -EIO;
}
*raw_super = (struct f2fs_super_block *)
((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
/* sanity checking of raw super */
if (!sanity_check_raw_super(sb, *raw_super))
return 0;
f2fs_msg(sb, KERN_ERR, "Can't find a valid F2FS filesystem "
"in %s superblock", super);
return -EINVAL;
}
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 buffer_head *raw_super_buf;
struct inode *root;
long err = -EINVAL;
int i;
/* allocate memory for f2fs-specific super block info */
sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
if (!sbi)
return -ENOMEM;
/* set a block size */
if (!sb_set_blocksize(sb, F2FS_BLKSIZE)) {
f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
goto free_sbi;
}
err = validate_superblock(sb, &raw_super, &raw_super_buf, 0);
if (err) {
brelse(raw_super_buf);
/* check secondary superblock when primary failed */
err = validate_superblock(sb, &raw_super, &raw_super_buf, 1);
if (err)
goto free_sb_buf;
}
/* init some FS parameters */
sbi->active_logs = NR_CURSEG_TYPE;
set_opt(sbi, BG_GC);
#ifdef CONFIG_F2FS_FS_XATTR
set_opt(sbi, XATTR_USER);
#endif
#ifdef CONFIG_F2FS_FS_POSIX_ACL
set_opt(sbi, POSIX_ACL);
#endif
/* parse mount options */
err = parse_options(sb, sbi, (char *)data);
if (err)
goto free_sb_buf;
sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
sb->s_max_links = F2FS_LINK_MAX;
get_random_bytes(&sbi->s_next_generation, sizeof(u32));
sb->s_op = &f2fs_sops;
sb->s_xattr = f2fs_xattr_handlers;
sb->s_export_op = &f2fs_export_ops;
sb->s_magic = F2FS_SUPER_MAGIC;
sb->s_fs_info = sbi;
sb->s_time_gran = 1;
sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
/* init f2fs-specific super block info */
sbi->sb = sb;
sbi->raw_super = raw_super;
sbi->raw_super_buf = raw_super_buf;
mutex_init(&sbi->gc_mutex);
mutex_init(&sbi->writepages);
mutex_init(&sbi->cp_mutex);
for (i = 0; i < NR_GLOBAL_LOCKS; i++)
mutex_init(&sbi->fs_lock[i]);
mutex_init(&sbi->node_write);
sbi->por_doing = 0;
spin_lock_init(&sbi->stat_lock);
init_rwsem(&sbi->bio_sem);
init_sb_info(sbi);
/* get an inode for meta space */
sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
if (IS_ERR(sbi->meta_inode)) {
f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
err = PTR_ERR(sbi->meta_inode);
goto free_sb_buf;
}
err = get_valid_checkpoint(sbi);
if (err) {
f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
goto free_meta_inode;
}
/* sanity checking of checkpoint */
err = -EINVAL;
if (sanity_check_ckpt(sbi)) {
f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
goto free_cp;
}
sbi->total_valid_node_count =
le32_to_cpu(sbi->ckpt->valid_node_count);
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->alloc_valid_block_count = 0;
INIT_LIST_HEAD(&sbi->dir_inode_list);
spin_lock_init(&sbi->dir_inode_lock);
init_orphan_info(sbi);
/* setup f2fs internal modules */
err = build_segment_manager(sbi);
if (err) {
f2fs_msg(sb, KERN_ERR,
"Failed to initialize F2FS segment manager");
goto free_sm;
}
err = build_node_manager(sbi);
if (err) {
f2fs_msg(sb, KERN_ERR,
"Failed to initialize F2FS node manager");
goto free_nm;
}
build_gc_manager(sbi);
/* get an inode for node space */
sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
if (IS_ERR(sbi->node_inode)) {
f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
err = PTR_ERR(sbi->node_inode);
goto free_nm;
}
/* if there are nt orphan nodes free them */
err = -EINVAL;
if (recover_orphan_inodes(sbi))
goto free_node_inode;
/* read root inode and dentry */
root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
if (IS_ERR(root)) {
f2fs_msg(sb, KERN_ERR, "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)
goto free_root_inode;
sb->s_root = d_make_root(root); /* allocate root dentry */
if (!sb->s_root) {
err = -ENOMEM;
goto free_root_inode;
}
/* recover fsynced data */
if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
err = recover_fsync_data(sbi);
if (err) {
f2fs_msg(sb, KERN_ERR, "Failed to recover fsync data");
goto free_root_inode;
}
}
/* After POR, we can run background GC thread */
err = start_gc_thread(sbi);
if (err)
goto fail;
err = f2fs_build_stats(sbi);
if (err)
goto fail;
if (test_opt(sbi, DISCARD)) {
struct request_queue *q = bdev_get_queue(sb->s_bdev);
if (!blk_queue_discard(q))
f2fs_msg(sb, KERN_WARNING,
"mounting with \"discard\" option, but "
"the device does not support discard");
}
return 0;
fail:
stop_gc_thread(sbi);
free_root_inode:
dput(sb->s_root);
sb->s_root = NULL;
free_node_inode:
iput(sbi->node_inode);
free_nm:
destroy_node_manager(sbi);
free_sm:
destroy_segment_manager(sbi);
free_cp:
kfree(sbi->ckpt);
free_meta_inode:
make_bad_inode(sbi->meta_inode);
iput(sbi->meta_inode);
free_sb_buf:
brelse(raw_super_buf);
free_sbi:
kfree(sbi);
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 struct file_system_type f2fs_fs_type = {
.owner = THIS_MODULE,
.name = "f2fs",
.mount = f2fs_mount,
.kill_sb = kill_block_super,
.fs_flags = FS_REQUIRES_DEV,
};
static int __init init_inodecache(void)
{
f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
sizeof(struct f2fs_inode_info), NULL);
if (f2fs_inode_cachep == NULL)
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;
err = init_inodecache();
if (err)
goto fail;
err = create_node_manager_caches();
if (err)
goto fail;
err = create_gc_caches();
if (err)
goto fail;
err = create_checkpoint_caches();
if (err)
goto fail;
err = register_filesystem(&f2fs_fs_type);
if (err)
goto fail;
f2fs_create_root_stats();
fail:
return err;
}
static void __exit exit_f2fs_fs(void)
{
f2fs_destroy_root_stats();
unregister_filesystem(&f2fs_fs_type);
destroy_checkpoint_caches();
destroy_gc_caches();
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");