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linux-next/fs/f2fs/super.c
Jaegeuk Kim 5ec4e49f9b f2fs: change GC bitmaps to apply the section granularity
This patch removes a bitmap for victim segments selected by foreground GC, and
modifies the other bitmap for victim segments selected by background GC.

1) foreground GC bitmap
 : We don't need to manage this, since we just only one previous victim section
   number instead of the whole victim history.
   The f2fs uses the victim section number in order not to allocate currently
   GC'ed section to current active logs.

2) background GC bitmap
 : This bitmap is used to avoid selecting victims repeatedly by background GCs.
   In addition, the victims are able to be selected by foreground GCs, since
   there is no need to read victim blocks during foreground GCs.

   By the fact that the foreground GC reclaims segments in a section unit, it'd
   be better to manage this bitmap based on the section granularity.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:49 +09:00

769 lines
18 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"
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);
if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
return 0;
if (sync)
write_checkpoint(sbi, false);
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 */
if (parse_options(sb, sbi, (char *)data))
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->write_inode);
mutex_init(&sbi->writepages);
mutex_init(&sbi->cp_mutex);
for (i = 0; i < NR_LOCK_TYPE; i++)
mutex_init(&sbi->fs_lock[i]);
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");