xref: /linux/fs/f2fs/super.c (revision 27ffaeb0ab160852c87e2dfa505594020e9a3a06)
1 /*
2  * fs/f2fs/super.c
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/fs.h>
14 #include <linux/statfs.h>
15 #include <linux/buffer_head.h>
16 #include <linux/backing-dev.h>
17 #include <linux/kthread.h>
18 #include <linux/parser.h>
19 #include <linux/mount.h>
20 #include <linux/seq_file.h>
21 #include <linux/proc_fs.h>
22 #include <linux/random.h>
23 #include <linux/exportfs.h>
24 #include <linux/blkdev.h>
25 #include <linux/f2fs_fs.h>
26 #include <linux/sysfs.h>
27 
28 #include "f2fs.h"
29 #include "node.h"
30 #include "segment.h"
31 #include "xattr.h"
32 #include "gc.h"
33 
34 #define CREATE_TRACE_POINTS
35 #include <trace/events/f2fs.h>
36 
37 static struct proc_dir_entry *f2fs_proc_root;
38 static struct kmem_cache *f2fs_inode_cachep;
39 static struct kset *f2fs_kset;
40 
41 enum {
42 	Opt_gc_background,
43 	Opt_disable_roll_forward,
44 	Opt_discard,
45 	Opt_noheap,
46 	Opt_user_xattr,
47 	Opt_nouser_xattr,
48 	Opt_acl,
49 	Opt_noacl,
50 	Opt_active_logs,
51 	Opt_disable_ext_identify,
52 	Opt_inline_xattr,
53 	Opt_inline_data,
54 	Opt_flush_merge,
55 	Opt_nobarrier,
56 	Opt_err,
57 };
58 
59 static match_table_t f2fs_tokens = {
60 	{Opt_gc_background, "background_gc=%s"},
61 	{Opt_disable_roll_forward, "disable_roll_forward"},
62 	{Opt_discard, "discard"},
63 	{Opt_noheap, "no_heap"},
64 	{Opt_user_xattr, "user_xattr"},
65 	{Opt_nouser_xattr, "nouser_xattr"},
66 	{Opt_acl, "acl"},
67 	{Opt_noacl, "noacl"},
68 	{Opt_active_logs, "active_logs=%u"},
69 	{Opt_disable_ext_identify, "disable_ext_identify"},
70 	{Opt_inline_xattr, "inline_xattr"},
71 	{Opt_inline_data, "inline_data"},
72 	{Opt_flush_merge, "flush_merge"},
73 	{Opt_nobarrier, "nobarrier"},
74 	{Opt_err, NULL},
75 };
76 
77 /* Sysfs support for f2fs */
78 enum {
79 	GC_THREAD,	/* struct f2fs_gc_thread */
80 	SM_INFO,	/* struct f2fs_sm_info */
81 	NM_INFO,	/* struct f2fs_nm_info */
82 	F2FS_SBI,	/* struct f2fs_sb_info */
83 };
84 
85 struct f2fs_attr {
86 	struct attribute attr;
87 	ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
88 	ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
89 			 const char *, size_t);
90 	int struct_type;
91 	int offset;
92 };
93 
94 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
95 {
96 	if (struct_type == GC_THREAD)
97 		return (unsigned char *)sbi->gc_thread;
98 	else if (struct_type == SM_INFO)
99 		return (unsigned char *)SM_I(sbi);
100 	else if (struct_type == NM_INFO)
101 		return (unsigned char *)NM_I(sbi);
102 	else if (struct_type == F2FS_SBI)
103 		return (unsigned char *)sbi;
104 	return NULL;
105 }
106 
107 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
108 			struct f2fs_sb_info *sbi, char *buf)
109 {
110 	unsigned char *ptr = NULL;
111 	unsigned int *ui;
112 
113 	ptr = __struct_ptr(sbi, a->struct_type);
114 	if (!ptr)
115 		return -EINVAL;
116 
117 	ui = (unsigned int *)(ptr + a->offset);
118 
119 	return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
120 }
121 
122 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
123 			struct f2fs_sb_info *sbi,
124 			const char *buf, size_t count)
125 {
126 	unsigned char *ptr;
127 	unsigned long t;
128 	unsigned int *ui;
129 	ssize_t ret;
130 
131 	ptr = __struct_ptr(sbi, a->struct_type);
132 	if (!ptr)
133 		return -EINVAL;
134 
135 	ui = (unsigned int *)(ptr + a->offset);
136 
137 	ret = kstrtoul(skip_spaces(buf), 0, &t);
138 	if (ret < 0)
139 		return ret;
140 	*ui = t;
141 	return count;
142 }
143 
144 static ssize_t f2fs_attr_show(struct kobject *kobj,
145 				struct attribute *attr, char *buf)
146 {
147 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
148 								s_kobj);
149 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
150 
151 	return a->show ? a->show(a, sbi, buf) : 0;
152 }
153 
154 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
155 						const char *buf, size_t len)
156 {
157 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
158 									s_kobj);
159 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
160 
161 	return a->store ? a->store(a, sbi, buf, len) : 0;
162 }
163 
164 static void f2fs_sb_release(struct kobject *kobj)
165 {
166 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
167 								s_kobj);
168 	complete(&sbi->s_kobj_unregister);
169 }
170 
171 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
172 static struct f2fs_attr f2fs_attr_##_name = {			\
173 	.attr = {.name = __stringify(_name), .mode = _mode },	\
174 	.show	= _show,					\
175 	.store	= _store,					\
176 	.struct_type = _struct_type,				\
177 	.offset = _offset					\
178 }
179 
180 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)	\
181 	F2FS_ATTR_OFFSET(struct_type, name, 0644,		\
182 		f2fs_sbi_show, f2fs_sbi_store,			\
183 		offsetof(struct struct_name, elname))
184 
185 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
186 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
187 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
188 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
189 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
190 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
191 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
192 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
193 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks);
194 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
195 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
196 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
197 
198 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
199 static struct attribute *f2fs_attrs[] = {
200 	ATTR_LIST(gc_min_sleep_time),
201 	ATTR_LIST(gc_max_sleep_time),
202 	ATTR_LIST(gc_no_gc_sleep_time),
203 	ATTR_LIST(gc_idle),
204 	ATTR_LIST(reclaim_segments),
205 	ATTR_LIST(max_small_discards),
206 	ATTR_LIST(ipu_policy),
207 	ATTR_LIST(min_ipu_util),
208 	ATTR_LIST(min_fsync_blocks),
209 	ATTR_LIST(max_victim_search),
210 	ATTR_LIST(dir_level),
211 	ATTR_LIST(ram_thresh),
212 	NULL,
213 };
214 
215 static const struct sysfs_ops f2fs_attr_ops = {
216 	.show	= f2fs_attr_show,
217 	.store	= f2fs_attr_store,
218 };
219 
220 static struct kobj_type f2fs_ktype = {
221 	.default_attrs	= f2fs_attrs,
222 	.sysfs_ops	= &f2fs_attr_ops,
223 	.release	= f2fs_sb_release,
224 };
225 
226 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
227 {
228 	struct va_format vaf;
229 	va_list args;
230 
231 	va_start(args, fmt);
232 	vaf.fmt = fmt;
233 	vaf.va = &args;
234 	printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
235 	va_end(args);
236 }
237 
238 static void init_once(void *foo)
239 {
240 	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
241 
242 	inode_init_once(&fi->vfs_inode);
243 }
244 
245 static int parse_options(struct super_block *sb, char *options)
246 {
247 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
248 	substring_t args[MAX_OPT_ARGS];
249 	char *p, *name;
250 	int arg = 0;
251 
252 	if (!options)
253 		return 0;
254 
255 	while ((p = strsep(&options, ",")) != NULL) {
256 		int token;
257 		if (!*p)
258 			continue;
259 		/*
260 		 * Initialize args struct so we know whether arg was
261 		 * found; some options take optional arguments.
262 		 */
263 		args[0].to = args[0].from = NULL;
264 		token = match_token(p, f2fs_tokens, args);
265 
266 		switch (token) {
267 		case Opt_gc_background:
268 			name = match_strdup(&args[0]);
269 
270 			if (!name)
271 				return -ENOMEM;
272 			if (strlen(name) == 2 && !strncmp(name, "on", 2))
273 				set_opt(sbi, BG_GC);
274 			else if (strlen(name) == 3 && !strncmp(name, "off", 3))
275 				clear_opt(sbi, BG_GC);
276 			else {
277 				kfree(name);
278 				return -EINVAL;
279 			}
280 			kfree(name);
281 			break;
282 		case Opt_disable_roll_forward:
283 			set_opt(sbi, DISABLE_ROLL_FORWARD);
284 			break;
285 		case Opt_discard:
286 			set_opt(sbi, DISCARD);
287 			break;
288 		case Opt_noheap:
289 			set_opt(sbi, NOHEAP);
290 			break;
291 #ifdef CONFIG_F2FS_FS_XATTR
292 		case Opt_user_xattr:
293 			set_opt(sbi, XATTR_USER);
294 			break;
295 		case Opt_nouser_xattr:
296 			clear_opt(sbi, XATTR_USER);
297 			break;
298 		case Opt_inline_xattr:
299 			set_opt(sbi, INLINE_XATTR);
300 			break;
301 #else
302 		case Opt_user_xattr:
303 			f2fs_msg(sb, KERN_INFO,
304 				"user_xattr options not supported");
305 			break;
306 		case Opt_nouser_xattr:
307 			f2fs_msg(sb, KERN_INFO,
308 				"nouser_xattr options not supported");
309 			break;
310 		case Opt_inline_xattr:
311 			f2fs_msg(sb, KERN_INFO,
312 				"inline_xattr options not supported");
313 			break;
314 #endif
315 #ifdef CONFIG_F2FS_FS_POSIX_ACL
316 		case Opt_acl:
317 			set_opt(sbi, POSIX_ACL);
318 			break;
319 		case Opt_noacl:
320 			clear_opt(sbi, POSIX_ACL);
321 			break;
322 #else
323 		case Opt_acl:
324 			f2fs_msg(sb, KERN_INFO, "acl options not supported");
325 			break;
326 		case Opt_noacl:
327 			f2fs_msg(sb, KERN_INFO, "noacl options not supported");
328 			break;
329 #endif
330 		case Opt_active_logs:
331 			if (args->from && match_int(args, &arg))
332 				return -EINVAL;
333 			if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
334 				return -EINVAL;
335 			sbi->active_logs = arg;
336 			break;
337 		case Opt_disable_ext_identify:
338 			set_opt(sbi, DISABLE_EXT_IDENTIFY);
339 			break;
340 		case Opt_inline_data:
341 			set_opt(sbi, INLINE_DATA);
342 			break;
343 		case Opt_flush_merge:
344 			set_opt(sbi, FLUSH_MERGE);
345 			break;
346 		case Opt_nobarrier:
347 			set_opt(sbi, NOBARRIER);
348 			break;
349 		default:
350 			f2fs_msg(sb, KERN_ERR,
351 				"Unrecognized mount option \"%s\" or missing value",
352 				p);
353 			return -EINVAL;
354 		}
355 	}
356 	return 0;
357 }
358 
359 static struct inode *f2fs_alloc_inode(struct super_block *sb)
360 {
361 	struct f2fs_inode_info *fi;
362 
363 	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
364 	if (!fi)
365 		return NULL;
366 
367 	init_once((void *) fi);
368 
369 	/* Initialize f2fs-specific inode info */
370 	fi->vfs_inode.i_version = 1;
371 	atomic_set(&fi->dirty_pages, 0);
372 	fi->i_current_depth = 1;
373 	fi->i_advise = 0;
374 	rwlock_init(&fi->ext.ext_lock);
375 	init_rwsem(&fi->i_sem);
376 	INIT_LIST_HEAD(&fi->inmem_pages);
377 	mutex_init(&fi->inmem_lock);
378 
379 	set_inode_flag(fi, FI_NEW_INODE);
380 
381 	if (test_opt(F2FS_SB(sb), INLINE_XATTR))
382 		set_inode_flag(fi, FI_INLINE_XATTR);
383 
384 	/* Will be used by directory only */
385 	fi->i_dir_level = F2FS_SB(sb)->dir_level;
386 
387 	return &fi->vfs_inode;
388 }
389 
390 static int f2fs_drop_inode(struct inode *inode)
391 {
392 	/*
393 	 * This is to avoid a deadlock condition like below.
394 	 * writeback_single_inode(inode)
395 	 *  - f2fs_write_data_page
396 	 *    - f2fs_gc -> iput -> evict
397 	 *       - inode_wait_for_writeback(inode)
398 	 */
399 	if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
400 		return 0;
401 	return generic_drop_inode(inode);
402 }
403 
404 /*
405  * f2fs_dirty_inode() is called from __mark_inode_dirty()
406  *
407  * We should call set_dirty_inode to write the dirty inode through write_inode.
408  */
409 static void f2fs_dirty_inode(struct inode *inode, int flags)
410 {
411 	set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
412 }
413 
414 static void f2fs_i_callback(struct rcu_head *head)
415 {
416 	struct inode *inode = container_of(head, struct inode, i_rcu);
417 	kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
418 }
419 
420 static void f2fs_destroy_inode(struct inode *inode)
421 {
422 	call_rcu(&inode->i_rcu, f2fs_i_callback);
423 }
424 
425 static void f2fs_put_super(struct super_block *sb)
426 {
427 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
428 
429 	if (sbi->s_proc) {
430 		remove_proc_entry("segment_info", sbi->s_proc);
431 		remove_proc_entry(sb->s_id, f2fs_proc_root);
432 	}
433 	kobject_del(&sbi->s_kobj);
434 
435 	f2fs_destroy_stats(sbi);
436 	stop_gc_thread(sbi);
437 
438 	/* We don't need to do checkpoint when it's clean */
439 	if (sbi->s_dirty) {
440 		struct cp_control cpc = {
441 			.reason = CP_UMOUNT,
442 		};
443 		write_checkpoint(sbi, &cpc);
444 	}
445 
446 	/*
447 	 * normally superblock is clean, so we need to release this.
448 	 * In addition, EIO will skip do checkpoint, we need this as well.
449 	 */
450 	release_dirty_inode(sbi);
451 	release_discard_addrs(sbi);
452 
453 	iput(sbi->node_inode);
454 	iput(sbi->meta_inode);
455 
456 	/* destroy f2fs internal modules */
457 	destroy_node_manager(sbi);
458 	destroy_segment_manager(sbi);
459 
460 	kfree(sbi->ckpt);
461 	kobject_put(&sbi->s_kobj);
462 	wait_for_completion(&sbi->s_kobj_unregister);
463 
464 	sb->s_fs_info = NULL;
465 	brelse(sbi->raw_super_buf);
466 	kfree(sbi);
467 }
468 
469 int f2fs_sync_fs(struct super_block *sb, int sync)
470 {
471 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
472 
473 	trace_f2fs_sync_fs(sb, sync);
474 
475 	if (sync) {
476 		struct cp_control cpc = {
477 			.reason = CP_SYNC,
478 		};
479 		mutex_lock(&sbi->gc_mutex);
480 		write_checkpoint(sbi, &cpc);
481 		mutex_unlock(&sbi->gc_mutex);
482 	} else {
483 		f2fs_balance_fs(sbi);
484 	}
485 
486 	return 0;
487 }
488 
489 static int f2fs_freeze(struct super_block *sb)
490 {
491 	int err;
492 
493 	if (f2fs_readonly(sb))
494 		return 0;
495 
496 	err = f2fs_sync_fs(sb, 1);
497 	return err;
498 }
499 
500 static int f2fs_unfreeze(struct super_block *sb)
501 {
502 	return 0;
503 }
504 
505 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
506 {
507 	struct super_block *sb = dentry->d_sb;
508 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
509 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
510 	block_t total_count, user_block_count, start_count, ovp_count;
511 
512 	total_count = le64_to_cpu(sbi->raw_super->block_count);
513 	user_block_count = sbi->user_block_count;
514 	start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
515 	ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
516 	buf->f_type = F2FS_SUPER_MAGIC;
517 	buf->f_bsize = sbi->blocksize;
518 
519 	buf->f_blocks = total_count - start_count;
520 	buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
521 	buf->f_bavail = user_block_count - valid_user_blocks(sbi);
522 
523 	buf->f_files = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
524 	buf->f_ffree = buf->f_files - valid_inode_count(sbi);
525 
526 	buf->f_namelen = F2FS_NAME_LEN;
527 	buf->f_fsid.val[0] = (u32)id;
528 	buf->f_fsid.val[1] = (u32)(id >> 32);
529 
530 	return 0;
531 }
532 
533 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
534 {
535 	struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
536 
537 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC))
538 		seq_printf(seq, ",background_gc=%s", "on");
539 	else
540 		seq_printf(seq, ",background_gc=%s", "off");
541 	if (test_opt(sbi, DISABLE_ROLL_FORWARD))
542 		seq_puts(seq, ",disable_roll_forward");
543 	if (test_opt(sbi, DISCARD))
544 		seq_puts(seq, ",discard");
545 	if (test_opt(sbi, NOHEAP))
546 		seq_puts(seq, ",no_heap_alloc");
547 #ifdef CONFIG_F2FS_FS_XATTR
548 	if (test_opt(sbi, XATTR_USER))
549 		seq_puts(seq, ",user_xattr");
550 	else
551 		seq_puts(seq, ",nouser_xattr");
552 	if (test_opt(sbi, INLINE_XATTR))
553 		seq_puts(seq, ",inline_xattr");
554 #endif
555 #ifdef CONFIG_F2FS_FS_POSIX_ACL
556 	if (test_opt(sbi, POSIX_ACL))
557 		seq_puts(seq, ",acl");
558 	else
559 		seq_puts(seq, ",noacl");
560 #endif
561 	if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
562 		seq_puts(seq, ",disable_ext_identify");
563 	if (test_opt(sbi, INLINE_DATA))
564 		seq_puts(seq, ",inline_data");
565 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
566 		seq_puts(seq, ",flush_merge");
567 	if (test_opt(sbi, NOBARRIER))
568 		seq_puts(seq, ",nobarrier");
569 	seq_printf(seq, ",active_logs=%u", sbi->active_logs);
570 
571 	return 0;
572 }
573 
574 static int segment_info_seq_show(struct seq_file *seq, void *offset)
575 {
576 	struct super_block *sb = seq->private;
577 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
578 	unsigned int total_segs =
579 			le32_to_cpu(sbi->raw_super->segment_count_main);
580 	int i;
581 
582 	seq_puts(seq, "format: segment_type|valid_blocks\n"
583 		"segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
584 
585 	for (i = 0; i < total_segs; i++) {
586 		struct seg_entry *se = get_seg_entry(sbi, i);
587 
588 		if ((i % 10) == 0)
589 			seq_printf(seq, "%-5d", i);
590 		seq_printf(seq, "%d|%-3u", se->type,
591 					get_valid_blocks(sbi, i, 1));
592 		if ((i % 10) == 9 || i == (total_segs - 1))
593 			seq_putc(seq, '\n');
594 		else
595 			seq_putc(seq, ' ');
596 	}
597 
598 	return 0;
599 }
600 
601 static int segment_info_open_fs(struct inode *inode, struct file *file)
602 {
603 	return single_open(file, segment_info_seq_show, PDE_DATA(inode));
604 }
605 
606 static const struct file_operations f2fs_seq_segment_info_fops = {
607 	.owner = THIS_MODULE,
608 	.open = segment_info_open_fs,
609 	.read = seq_read,
610 	.llseek = seq_lseek,
611 	.release = single_release,
612 };
613 
614 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
615 {
616 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
617 	struct f2fs_mount_info org_mount_opt;
618 	int err, active_logs;
619 	bool need_restart_gc = false;
620 	bool need_stop_gc = false;
621 
622 	sync_filesystem(sb);
623 
624 	/*
625 	 * Save the old mount options in case we
626 	 * need to restore them.
627 	 */
628 	org_mount_opt = sbi->mount_opt;
629 	active_logs = sbi->active_logs;
630 
631 	sbi->mount_opt.opt = 0;
632 	sbi->active_logs = NR_CURSEG_TYPE;
633 
634 	/* parse mount options */
635 	err = parse_options(sb, data);
636 	if (err)
637 		goto restore_opts;
638 
639 	/*
640 	 * Previous and new state of filesystem is RO,
641 	 * so skip checking GC and FLUSH_MERGE conditions.
642 	 */
643 	if (f2fs_readonly(sb) && (*flags & MS_RDONLY))
644 		goto skip;
645 
646 	/*
647 	 * We stop the GC thread if FS is mounted as RO
648 	 * or if background_gc = off is passed in mount
649 	 * option. Also sync the filesystem.
650 	 */
651 	if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
652 		if (sbi->gc_thread) {
653 			stop_gc_thread(sbi);
654 			f2fs_sync_fs(sb, 1);
655 			need_restart_gc = true;
656 		}
657 	} else if (test_opt(sbi, BG_GC) && !sbi->gc_thread) {
658 		err = start_gc_thread(sbi);
659 		if (err)
660 			goto restore_opts;
661 		need_stop_gc = true;
662 	}
663 
664 	/*
665 	 * We stop issue flush thread if FS is mounted as RO
666 	 * or if flush_merge is not passed in mount option.
667 	 */
668 	if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
669 		destroy_flush_cmd_control(sbi);
670 	} else if (test_opt(sbi, FLUSH_MERGE) && !SM_I(sbi)->cmd_control_info) {
671 		err = create_flush_cmd_control(sbi);
672 		if (err)
673 			goto restore_gc;
674 	}
675 skip:
676 	/* Update the POSIXACL Flag */
677 	 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
678 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
679 	return 0;
680 restore_gc:
681 	if (need_restart_gc) {
682 		if (start_gc_thread(sbi))
683 			f2fs_msg(sbi->sb, KERN_WARNING,
684 				"background gc thread has stopped");
685 	} else if (need_stop_gc) {
686 		stop_gc_thread(sbi);
687 	}
688 restore_opts:
689 	sbi->mount_opt = org_mount_opt;
690 	sbi->active_logs = active_logs;
691 	return err;
692 }
693 
694 static struct super_operations f2fs_sops = {
695 	.alloc_inode	= f2fs_alloc_inode,
696 	.drop_inode	= f2fs_drop_inode,
697 	.destroy_inode	= f2fs_destroy_inode,
698 	.write_inode	= f2fs_write_inode,
699 	.dirty_inode	= f2fs_dirty_inode,
700 	.show_options	= f2fs_show_options,
701 	.evict_inode	= f2fs_evict_inode,
702 	.put_super	= f2fs_put_super,
703 	.sync_fs	= f2fs_sync_fs,
704 	.freeze_fs	= f2fs_freeze,
705 	.unfreeze_fs	= f2fs_unfreeze,
706 	.statfs		= f2fs_statfs,
707 	.remount_fs	= f2fs_remount,
708 };
709 
710 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
711 		u64 ino, u32 generation)
712 {
713 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
714 	struct inode *inode;
715 
716 	if (check_nid_range(sbi, ino))
717 		return ERR_PTR(-ESTALE);
718 
719 	/*
720 	 * f2fs_iget isn't quite right if the inode is currently unallocated!
721 	 * However f2fs_iget currently does appropriate checks to handle stale
722 	 * inodes so everything is OK.
723 	 */
724 	inode = f2fs_iget(sb, ino);
725 	if (IS_ERR(inode))
726 		return ERR_CAST(inode);
727 	if (unlikely(generation && inode->i_generation != generation)) {
728 		/* we didn't find the right inode.. */
729 		iput(inode);
730 		return ERR_PTR(-ESTALE);
731 	}
732 	return inode;
733 }
734 
735 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
736 		int fh_len, int fh_type)
737 {
738 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
739 				    f2fs_nfs_get_inode);
740 }
741 
742 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
743 		int fh_len, int fh_type)
744 {
745 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
746 				    f2fs_nfs_get_inode);
747 }
748 
749 static const struct export_operations f2fs_export_ops = {
750 	.fh_to_dentry = f2fs_fh_to_dentry,
751 	.fh_to_parent = f2fs_fh_to_parent,
752 	.get_parent = f2fs_get_parent,
753 };
754 
755 static loff_t max_file_size(unsigned bits)
756 {
757 	loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
758 	loff_t leaf_count = ADDRS_PER_BLOCK;
759 
760 	/* two direct node blocks */
761 	result += (leaf_count * 2);
762 
763 	/* two indirect node blocks */
764 	leaf_count *= NIDS_PER_BLOCK;
765 	result += (leaf_count * 2);
766 
767 	/* one double indirect node block */
768 	leaf_count *= NIDS_PER_BLOCK;
769 	result += leaf_count;
770 
771 	result <<= bits;
772 	return result;
773 }
774 
775 static int sanity_check_raw_super(struct super_block *sb,
776 			struct f2fs_super_block *raw_super)
777 {
778 	unsigned int blocksize;
779 
780 	if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
781 		f2fs_msg(sb, KERN_INFO,
782 			"Magic Mismatch, valid(0x%x) - read(0x%x)",
783 			F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
784 		return 1;
785 	}
786 
787 	/* Currently, support only 4KB page cache size */
788 	if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
789 		f2fs_msg(sb, KERN_INFO,
790 			"Invalid page_cache_size (%lu), supports only 4KB\n",
791 			PAGE_CACHE_SIZE);
792 		return 1;
793 	}
794 
795 	/* Currently, support only 4KB block size */
796 	blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
797 	if (blocksize != F2FS_BLKSIZE) {
798 		f2fs_msg(sb, KERN_INFO,
799 			"Invalid blocksize (%u), supports only 4KB\n",
800 			blocksize);
801 		return 1;
802 	}
803 
804 	/* Currently, support 512/1024/2048/4096 bytes sector size */
805 	if (le32_to_cpu(raw_super->log_sectorsize) >
806 				F2FS_MAX_LOG_SECTOR_SIZE ||
807 		le32_to_cpu(raw_super->log_sectorsize) <
808 				F2FS_MIN_LOG_SECTOR_SIZE) {
809 		f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize (%u)",
810 			le32_to_cpu(raw_super->log_sectorsize));
811 		return 1;
812 	}
813 	if (le32_to_cpu(raw_super->log_sectors_per_block) +
814 		le32_to_cpu(raw_super->log_sectorsize) !=
815 			F2FS_MAX_LOG_SECTOR_SIZE) {
816 		f2fs_msg(sb, KERN_INFO,
817 			"Invalid log sectors per block(%u) log sectorsize(%u)",
818 			le32_to_cpu(raw_super->log_sectors_per_block),
819 			le32_to_cpu(raw_super->log_sectorsize));
820 		return 1;
821 	}
822 	return 0;
823 }
824 
825 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
826 {
827 	unsigned int total, fsmeta;
828 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
829 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
830 
831 	total = le32_to_cpu(raw_super->segment_count);
832 	fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
833 	fsmeta += le32_to_cpu(raw_super->segment_count_sit);
834 	fsmeta += le32_to_cpu(raw_super->segment_count_nat);
835 	fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
836 	fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
837 
838 	if (unlikely(fsmeta >= total))
839 		return 1;
840 
841 	if (unlikely(f2fs_cp_error(sbi))) {
842 		f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
843 		return 1;
844 	}
845 	return 0;
846 }
847 
848 static void init_sb_info(struct f2fs_sb_info *sbi)
849 {
850 	struct f2fs_super_block *raw_super = sbi->raw_super;
851 	int i;
852 
853 	sbi->log_sectors_per_block =
854 		le32_to_cpu(raw_super->log_sectors_per_block);
855 	sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
856 	sbi->blocksize = 1 << sbi->log_blocksize;
857 	sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
858 	sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
859 	sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
860 	sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
861 	sbi->total_sections = le32_to_cpu(raw_super->section_count);
862 	sbi->total_node_count =
863 		(le32_to_cpu(raw_super->segment_count_nat) / 2)
864 			* sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
865 	sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
866 	sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
867 	sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
868 	sbi->cur_victim_sec = NULL_SECNO;
869 	sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
870 
871 	for (i = 0; i < NR_COUNT_TYPE; i++)
872 		atomic_set(&sbi->nr_pages[i], 0);
873 
874 	sbi->dir_level = DEF_DIR_LEVEL;
875 	sbi->need_fsck = false;
876 }
877 
878 /*
879  * Read f2fs raw super block.
880  * Because we have two copies of super block, so read the first one at first,
881  * if the first one is invalid, move to read the second one.
882  */
883 static int read_raw_super_block(struct super_block *sb,
884 			struct f2fs_super_block **raw_super,
885 			struct buffer_head **raw_super_buf)
886 {
887 	int block = 0;
888 
889 retry:
890 	*raw_super_buf = sb_bread(sb, block);
891 	if (!*raw_super_buf) {
892 		f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
893 				block + 1);
894 		if (block == 0) {
895 			block++;
896 			goto retry;
897 		} else {
898 			return -EIO;
899 		}
900 	}
901 
902 	*raw_super = (struct f2fs_super_block *)
903 		((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
904 
905 	/* sanity checking of raw super */
906 	if (sanity_check_raw_super(sb, *raw_super)) {
907 		brelse(*raw_super_buf);
908 		f2fs_msg(sb, KERN_ERR,
909 			"Can't find valid F2FS filesystem in %dth superblock",
910 								block + 1);
911 		if (block == 0) {
912 			block++;
913 			goto retry;
914 		} else {
915 			return -EINVAL;
916 		}
917 	}
918 
919 	return 0;
920 }
921 
922 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
923 {
924 	struct f2fs_sb_info *sbi;
925 	struct f2fs_super_block *raw_super;
926 	struct buffer_head *raw_super_buf;
927 	struct inode *root;
928 	long err = -EINVAL;
929 	bool retry = true;
930 	int i;
931 
932 try_onemore:
933 	/* allocate memory for f2fs-specific super block info */
934 	sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
935 	if (!sbi)
936 		return -ENOMEM;
937 
938 	/* set a block size */
939 	if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
940 		f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
941 		goto free_sbi;
942 	}
943 
944 	err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
945 	if (err)
946 		goto free_sbi;
947 
948 	sb->s_fs_info = sbi;
949 	/* init some FS parameters */
950 	sbi->active_logs = NR_CURSEG_TYPE;
951 
952 	set_opt(sbi, BG_GC);
953 
954 #ifdef CONFIG_F2FS_FS_XATTR
955 	set_opt(sbi, XATTR_USER);
956 #endif
957 #ifdef CONFIG_F2FS_FS_POSIX_ACL
958 	set_opt(sbi, POSIX_ACL);
959 #endif
960 	/* parse mount options */
961 	err = parse_options(sb, (char *)data);
962 	if (err)
963 		goto free_sb_buf;
964 
965 	sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
966 	sb->s_max_links = F2FS_LINK_MAX;
967 	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
968 
969 	sb->s_op = &f2fs_sops;
970 	sb->s_xattr = f2fs_xattr_handlers;
971 	sb->s_export_op = &f2fs_export_ops;
972 	sb->s_magic = F2FS_SUPER_MAGIC;
973 	sb->s_time_gran = 1;
974 	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
975 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
976 	memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
977 
978 	/* init f2fs-specific super block info */
979 	sbi->sb = sb;
980 	sbi->raw_super = raw_super;
981 	sbi->raw_super_buf = raw_super_buf;
982 	mutex_init(&sbi->gc_mutex);
983 	mutex_init(&sbi->writepages);
984 	mutex_init(&sbi->cp_mutex);
985 	init_rwsem(&sbi->node_write);
986 	sbi->por_doing = false;
987 	spin_lock_init(&sbi->stat_lock);
988 
989 	init_rwsem(&sbi->read_io.io_rwsem);
990 	sbi->read_io.sbi = sbi;
991 	sbi->read_io.bio = NULL;
992 	for (i = 0; i < NR_PAGE_TYPE; i++) {
993 		init_rwsem(&sbi->write_io[i].io_rwsem);
994 		sbi->write_io[i].sbi = sbi;
995 		sbi->write_io[i].bio = NULL;
996 	}
997 
998 	init_rwsem(&sbi->cp_rwsem);
999 	init_waitqueue_head(&sbi->cp_wait);
1000 	init_sb_info(sbi);
1001 
1002 	/* get an inode for meta space */
1003 	sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
1004 	if (IS_ERR(sbi->meta_inode)) {
1005 		f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
1006 		err = PTR_ERR(sbi->meta_inode);
1007 		goto free_sb_buf;
1008 	}
1009 
1010 	err = get_valid_checkpoint(sbi);
1011 	if (err) {
1012 		f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
1013 		goto free_meta_inode;
1014 	}
1015 
1016 	/* sanity checking of checkpoint */
1017 	err = -EINVAL;
1018 	if (sanity_check_ckpt(sbi)) {
1019 		f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
1020 		goto free_cp;
1021 	}
1022 
1023 	sbi->total_valid_node_count =
1024 				le32_to_cpu(sbi->ckpt->valid_node_count);
1025 	sbi->total_valid_inode_count =
1026 				le32_to_cpu(sbi->ckpt->valid_inode_count);
1027 	sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
1028 	sbi->total_valid_block_count =
1029 				le64_to_cpu(sbi->ckpt->valid_block_count);
1030 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1031 	sbi->alloc_valid_block_count = 0;
1032 	INIT_LIST_HEAD(&sbi->dir_inode_list);
1033 	spin_lock_init(&sbi->dir_inode_lock);
1034 
1035 	init_ino_entry_info(sbi);
1036 
1037 	/* setup f2fs internal modules */
1038 	err = build_segment_manager(sbi);
1039 	if (err) {
1040 		f2fs_msg(sb, KERN_ERR,
1041 			"Failed to initialize F2FS segment manager");
1042 		goto free_sm;
1043 	}
1044 	err = build_node_manager(sbi);
1045 	if (err) {
1046 		f2fs_msg(sb, KERN_ERR,
1047 			"Failed to initialize F2FS node manager");
1048 		goto free_nm;
1049 	}
1050 
1051 	build_gc_manager(sbi);
1052 
1053 	/* get an inode for node space */
1054 	sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1055 	if (IS_ERR(sbi->node_inode)) {
1056 		f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1057 		err = PTR_ERR(sbi->node_inode);
1058 		goto free_nm;
1059 	}
1060 
1061 	/* if there are nt orphan nodes free them */
1062 	recover_orphan_inodes(sbi);
1063 
1064 	/* read root inode and dentry */
1065 	root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1066 	if (IS_ERR(root)) {
1067 		f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1068 		err = PTR_ERR(root);
1069 		goto free_node_inode;
1070 	}
1071 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1072 		iput(root);
1073 		err = -EINVAL;
1074 		goto free_node_inode;
1075 	}
1076 
1077 	sb->s_root = d_make_root(root); /* allocate root dentry */
1078 	if (!sb->s_root) {
1079 		err = -ENOMEM;
1080 		goto free_root_inode;
1081 	}
1082 
1083 	err = f2fs_build_stats(sbi);
1084 	if (err)
1085 		goto free_root_inode;
1086 
1087 	if (f2fs_proc_root)
1088 		sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1089 
1090 	if (sbi->s_proc)
1091 		proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1092 				 &f2fs_seq_segment_info_fops, sb);
1093 
1094 	if (test_opt(sbi, DISCARD)) {
1095 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1096 		if (!blk_queue_discard(q))
1097 			f2fs_msg(sb, KERN_WARNING,
1098 					"mounting with \"discard\" option, but "
1099 					"the device does not support discard");
1100 	}
1101 
1102 	sbi->s_kobj.kset = f2fs_kset;
1103 	init_completion(&sbi->s_kobj_unregister);
1104 	err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1105 							"%s", sb->s_id);
1106 	if (err)
1107 		goto free_proc;
1108 
1109 	if (!retry)
1110 		sbi->need_fsck = true;
1111 
1112 	/* recover fsynced data */
1113 	if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1114 		err = recover_fsync_data(sbi);
1115 		if (err) {
1116 			f2fs_msg(sb, KERN_ERR,
1117 				"Cannot recover all fsync data errno=%ld", err);
1118 			goto free_kobj;
1119 		}
1120 	}
1121 
1122 	/*
1123 	 * If filesystem is not mounted as read-only then
1124 	 * do start the gc_thread.
1125 	 */
1126 	if (!f2fs_readonly(sb)) {
1127 		/* After POR, we can run background GC thread.*/
1128 		err = start_gc_thread(sbi);
1129 		if (err)
1130 			goto free_kobj;
1131 	}
1132 	return 0;
1133 
1134 free_kobj:
1135 	kobject_del(&sbi->s_kobj);
1136 free_proc:
1137 	if (sbi->s_proc) {
1138 		remove_proc_entry("segment_info", sbi->s_proc);
1139 		remove_proc_entry(sb->s_id, f2fs_proc_root);
1140 	}
1141 	f2fs_destroy_stats(sbi);
1142 free_root_inode:
1143 	dput(sb->s_root);
1144 	sb->s_root = NULL;
1145 free_node_inode:
1146 	iput(sbi->node_inode);
1147 free_nm:
1148 	destroy_node_manager(sbi);
1149 free_sm:
1150 	destroy_segment_manager(sbi);
1151 free_cp:
1152 	kfree(sbi->ckpt);
1153 free_meta_inode:
1154 	make_bad_inode(sbi->meta_inode);
1155 	iput(sbi->meta_inode);
1156 free_sb_buf:
1157 	brelse(raw_super_buf);
1158 free_sbi:
1159 	kfree(sbi);
1160 
1161 	/* give only one another chance */
1162 	if (retry) {
1163 		retry = 0;
1164 		shrink_dcache_sb(sb);
1165 		goto try_onemore;
1166 	}
1167 	return err;
1168 }
1169 
1170 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1171 			const char *dev_name, void *data)
1172 {
1173 	return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1174 }
1175 
1176 static struct file_system_type f2fs_fs_type = {
1177 	.owner		= THIS_MODULE,
1178 	.name		= "f2fs",
1179 	.mount		= f2fs_mount,
1180 	.kill_sb	= kill_block_super,
1181 	.fs_flags	= FS_REQUIRES_DEV,
1182 };
1183 MODULE_ALIAS_FS("f2fs");
1184 
1185 static int __init init_inodecache(void)
1186 {
1187 	f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1188 			sizeof(struct f2fs_inode_info));
1189 	if (!f2fs_inode_cachep)
1190 		return -ENOMEM;
1191 	return 0;
1192 }
1193 
1194 static void destroy_inodecache(void)
1195 {
1196 	/*
1197 	 * Make sure all delayed rcu free inodes are flushed before we
1198 	 * destroy cache.
1199 	 */
1200 	rcu_barrier();
1201 	kmem_cache_destroy(f2fs_inode_cachep);
1202 }
1203 
1204 static int __init init_f2fs_fs(void)
1205 {
1206 	int err;
1207 
1208 	err = init_inodecache();
1209 	if (err)
1210 		goto fail;
1211 	err = create_node_manager_caches();
1212 	if (err)
1213 		goto free_inodecache;
1214 	err = create_segment_manager_caches();
1215 	if (err)
1216 		goto free_node_manager_caches;
1217 	err = create_gc_caches();
1218 	if (err)
1219 		goto free_segment_manager_caches;
1220 	err = create_checkpoint_caches();
1221 	if (err)
1222 		goto free_gc_caches;
1223 	f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1224 	if (!f2fs_kset) {
1225 		err = -ENOMEM;
1226 		goto free_checkpoint_caches;
1227 	}
1228 	err = register_filesystem(&f2fs_fs_type);
1229 	if (err)
1230 		goto free_kset;
1231 	f2fs_create_root_stats();
1232 	f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1233 	return 0;
1234 
1235 free_kset:
1236 	kset_unregister(f2fs_kset);
1237 free_checkpoint_caches:
1238 	destroy_checkpoint_caches();
1239 free_gc_caches:
1240 	destroy_gc_caches();
1241 free_segment_manager_caches:
1242 	destroy_segment_manager_caches();
1243 free_node_manager_caches:
1244 	destroy_node_manager_caches();
1245 free_inodecache:
1246 	destroy_inodecache();
1247 fail:
1248 	return err;
1249 }
1250 
1251 static void __exit exit_f2fs_fs(void)
1252 {
1253 	remove_proc_entry("fs/f2fs", NULL);
1254 	f2fs_destroy_root_stats();
1255 	unregister_filesystem(&f2fs_fs_type);
1256 	destroy_checkpoint_caches();
1257 	destroy_gc_caches();
1258 	destroy_segment_manager_caches();
1259 	destroy_node_manager_caches();
1260 	destroy_inodecache();
1261 	kset_unregister(f2fs_kset);
1262 }
1263 
1264 module_init(init_f2fs_fs)
1265 module_exit(exit_f2fs_fs)
1266 
1267 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1268 MODULE_DESCRIPTION("Flash Friendly File System");
1269 MODULE_LICENSE("GPL");
1270