xref: /openbmc/linux/fs/f2fs/super.c (revision caf0047e7e1e60a7ad1d655d3b81b32e2dfb6095)
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 #include "trace.h"
34 
35 #define CREATE_TRACE_POINTS
36 #include <trace/events/f2fs.h>
37 
38 static struct proc_dir_entry *f2fs_proc_root;
39 static struct kmem_cache *f2fs_inode_cachep;
40 static struct kset *f2fs_kset;
41 
42 enum {
43 	Opt_gc_background,
44 	Opt_disable_roll_forward,
45 	Opt_discard,
46 	Opt_noheap,
47 	Opt_user_xattr,
48 	Opt_nouser_xattr,
49 	Opt_acl,
50 	Opt_noacl,
51 	Opt_active_logs,
52 	Opt_disable_ext_identify,
53 	Opt_inline_xattr,
54 	Opt_inline_data,
55 	Opt_inline_dentry,
56 	Opt_flush_merge,
57 	Opt_nobarrier,
58 	Opt_fastboot,
59 	Opt_err,
60 };
61 
62 static match_table_t f2fs_tokens = {
63 	{Opt_gc_background, "background_gc=%s"},
64 	{Opt_disable_roll_forward, "disable_roll_forward"},
65 	{Opt_discard, "discard"},
66 	{Opt_noheap, "no_heap"},
67 	{Opt_user_xattr, "user_xattr"},
68 	{Opt_nouser_xattr, "nouser_xattr"},
69 	{Opt_acl, "acl"},
70 	{Opt_noacl, "noacl"},
71 	{Opt_active_logs, "active_logs=%u"},
72 	{Opt_disable_ext_identify, "disable_ext_identify"},
73 	{Opt_inline_xattr, "inline_xattr"},
74 	{Opt_inline_data, "inline_data"},
75 	{Opt_inline_dentry, "inline_dentry"},
76 	{Opt_flush_merge, "flush_merge"},
77 	{Opt_nobarrier, "nobarrier"},
78 	{Opt_fastboot, "fastboot"},
79 	{Opt_err, NULL},
80 };
81 
82 /* Sysfs support for f2fs */
83 enum {
84 	GC_THREAD,	/* struct f2fs_gc_thread */
85 	SM_INFO,	/* struct f2fs_sm_info */
86 	NM_INFO,	/* struct f2fs_nm_info */
87 	F2FS_SBI,	/* struct f2fs_sb_info */
88 };
89 
90 struct f2fs_attr {
91 	struct attribute attr;
92 	ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
93 	ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
94 			 const char *, size_t);
95 	int struct_type;
96 	int offset;
97 };
98 
99 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
100 {
101 	if (struct_type == GC_THREAD)
102 		return (unsigned char *)sbi->gc_thread;
103 	else if (struct_type == SM_INFO)
104 		return (unsigned char *)SM_I(sbi);
105 	else if (struct_type == NM_INFO)
106 		return (unsigned char *)NM_I(sbi);
107 	else if (struct_type == F2FS_SBI)
108 		return (unsigned char *)sbi;
109 	return NULL;
110 }
111 
112 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
113 			struct f2fs_sb_info *sbi, char *buf)
114 {
115 	unsigned char *ptr = NULL;
116 	unsigned int *ui;
117 
118 	ptr = __struct_ptr(sbi, a->struct_type);
119 	if (!ptr)
120 		return -EINVAL;
121 
122 	ui = (unsigned int *)(ptr + a->offset);
123 
124 	return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
125 }
126 
127 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
128 			struct f2fs_sb_info *sbi,
129 			const char *buf, size_t count)
130 {
131 	unsigned char *ptr;
132 	unsigned long t;
133 	unsigned int *ui;
134 	ssize_t ret;
135 
136 	ptr = __struct_ptr(sbi, a->struct_type);
137 	if (!ptr)
138 		return -EINVAL;
139 
140 	ui = (unsigned int *)(ptr + a->offset);
141 
142 	ret = kstrtoul(skip_spaces(buf), 0, &t);
143 	if (ret < 0)
144 		return ret;
145 	*ui = t;
146 	return count;
147 }
148 
149 static ssize_t f2fs_attr_show(struct kobject *kobj,
150 				struct attribute *attr, char *buf)
151 {
152 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
153 								s_kobj);
154 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
155 
156 	return a->show ? a->show(a, sbi, buf) : 0;
157 }
158 
159 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
160 						const char *buf, size_t len)
161 {
162 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
163 									s_kobj);
164 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
165 
166 	return a->store ? a->store(a, sbi, buf, len) : 0;
167 }
168 
169 static void f2fs_sb_release(struct kobject *kobj)
170 {
171 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
172 								s_kobj);
173 	complete(&sbi->s_kobj_unregister);
174 }
175 
176 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
177 static struct f2fs_attr f2fs_attr_##_name = {			\
178 	.attr = {.name = __stringify(_name), .mode = _mode },	\
179 	.show	= _show,					\
180 	.store	= _store,					\
181 	.struct_type = _struct_type,				\
182 	.offset = _offset					\
183 }
184 
185 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)	\
186 	F2FS_ATTR_OFFSET(struct_type, name, 0644,		\
187 		f2fs_sbi_show, f2fs_sbi_store,			\
188 		offsetof(struct struct_name, elname))
189 
190 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
191 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
192 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
193 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
194 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
195 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
196 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
197 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
198 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks);
199 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
200 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
201 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
202 
203 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
204 static struct attribute *f2fs_attrs[] = {
205 	ATTR_LIST(gc_min_sleep_time),
206 	ATTR_LIST(gc_max_sleep_time),
207 	ATTR_LIST(gc_no_gc_sleep_time),
208 	ATTR_LIST(gc_idle),
209 	ATTR_LIST(reclaim_segments),
210 	ATTR_LIST(max_small_discards),
211 	ATTR_LIST(ipu_policy),
212 	ATTR_LIST(min_ipu_util),
213 	ATTR_LIST(min_fsync_blocks),
214 	ATTR_LIST(max_victim_search),
215 	ATTR_LIST(dir_level),
216 	ATTR_LIST(ram_thresh),
217 	NULL,
218 };
219 
220 static const struct sysfs_ops f2fs_attr_ops = {
221 	.show	= f2fs_attr_show,
222 	.store	= f2fs_attr_store,
223 };
224 
225 static struct kobj_type f2fs_ktype = {
226 	.default_attrs	= f2fs_attrs,
227 	.sysfs_ops	= &f2fs_attr_ops,
228 	.release	= f2fs_sb_release,
229 };
230 
231 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
232 {
233 	struct va_format vaf;
234 	va_list args;
235 
236 	va_start(args, fmt);
237 	vaf.fmt = fmt;
238 	vaf.va = &args;
239 	printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
240 	va_end(args);
241 }
242 
243 static void init_once(void *foo)
244 {
245 	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
246 
247 	inode_init_once(&fi->vfs_inode);
248 }
249 
250 static int parse_options(struct super_block *sb, char *options)
251 {
252 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
253 	substring_t args[MAX_OPT_ARGS];
254 	char *p, *name;
255 	int arg = 0;
256 
257 	if (!options)
258 		return 0;
259 
260 	while ((p = strsep(&options, ",")) != NULL) {
261 		int token;
262 		if (!*p)
263 			continue;
264 		/*
265 		 * Initialize args struct so we know whether arg was
266 		 * found; some options take optional arguments.
267 		 */
268 		args[0].to = args[0].from = NULL;
269 		token = match_token(p, f2fs_tokens, args);
270 
271 		switch (token) {
272 		case Opt_gc_background:
273 			name = match_strdup(&args[0]);
274 
275 			if (!name)
276 				return -ENOMEM;
277 			if (strlen(name) == 2 && !strncmp(name, "on", 2))
278 				set_opt(sbi, BG_GC);
279 			else if (strlen(name) == 3 && !strncmp(name, "off", 3))
280 				clear_opt(sbi, BG_GC);
281 			else {
282 				kfree(name);
283 				return -EINVAL;
284 			}
285 			kfree(name);
286 			break;
287 		case Opt_disable_roll_forward:
288 			set_opt(sbi, DISABLE_ROLL_FORWARD);
289 			break;
290 		case Opt_discard:
291 			set_opt(sbi, DISCARD);
292 			break;
293 		case Opt_noheap:
294 			set_opt(sbi, NOHEAP);
295 			break;
296 #ifdef CONFIG_F2FS_FS_XATTR
297 		case Opt_user_xattr:
298 			set_opt(sbi, XATTR_USER);
299 			break;
300 		case Opt_nouser_xattr:
301 			clear_opt(sbi, XATTR_USER);
302 			break;
303 		case Opt_inline_xattr:
304 			set_opt(sbi, INLINE_XATTR);
305 			break;
306 #else
307 		case Opt_user_xattr:
308 			f2fs_msg(sb, KERN_INFO,
309 				"user_xattr options not supported");
310 			break;
311 		case Opt_nouser_xattr:
312 			f2fs_msg(sb, KERN_INFO,
313 				"nouser_xattr options not supported");
314 			break;
315 		case Opt_inline_xattr:
316 			f2fs_msg(sb, KERN_INFO,
317 				"inline_xattr options not supported");
318 			break;
319 #endif
320 #ifdef CONFIG_F2FS_FS_POSIX_ACL
321 		case Opt_acl:
322 			set_opt(sbi, POSIX_ACL);
323 			break;
324 		case Opt_noacl:
325 			clear_opt(sbi, POSIX_ACL);
326 			break;
327 #else
328 		case Opt_acl:
329 			f2fs_msg(sb, KERN_INFO, "acl options not supported");
330 			break;
331 		case Opt_noacl:
332 			f2fs_msg(sb, KERN_INFO, "noacl options not supported");
333 			break;
334 #endif
335 		case Opt_active_logs:
336 			if (args->from && match_int(args, &arg))
337 				return -EINVAL;
338 			if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
339 				return -EINVAL;
340 			sbi->active_logs = arg;
341 			break;
342 		case Opt_disable_ext_identify:
343 			set_opt(sbi, DISABLE_EXT_IDENTIFY);
344 			break;
345 		case Opt_inline_data:
346 			set_opt(sbi, INLINE_DATA);
347 			break;
348 		case Opt_inline_dentry:
349 			set_opt(sbi, INLINE_DENTRY);
350 			break;
351 		case Opt_flush_merge:
352 			set_opt(sbi, FLUSH_MERGE);
353 			break;
354 		case Opt_nobarrier:
355 			set_opt(sbi, NOBARRIER);
356 			break;
357 		case Opt_fastboot:
358 			set_opt(sbi, FASTBOOT);
359 			break;
360 		default:
361 			f2fs_msg(sb, KERN_ERR,
362 				"Unrecognized mount option \"%s\" or missing value",
363 				p);
364 			return -EINVAL;
365 		}
366 	}
367 	return 0;
368 }
369 
370 static struct inode *f2fs_alloc_inode(struct super_block *sb)
371 {
372 	struct f2fs_inode_info *fi;
373 
374 	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
375 	if (!fi)
376 		return NULL;
377 
378 	init_once((void *) fi);
379 
380 	/* Initialize f2fs-specific inode info */
381 	fi->vfs_inode.i_version = 1;
382 	atomic_set(&fi->dirty_pages, 0);
383 	fi->i_current_depth = 1;
384 	fi->i_advise = 0;
385 	rwlock_init(&fi->ext.ext_lock);
386 	init_rwsem(&fi->i_sem);
387 	INIT_RADIX_TREE(&fi->inmem_root, GFP_NOFS);
388 	INIT_LIST_HEAD(&fi->inmem_pages);
389 	mutex_init(&fi->inmem_lock);
390 
391 	set_inode_flag(fi, FI_NEW_INODE);
392 
393 	if (test_opt(F2FS_SB(sb), INLINE_XATTR))
394 		set_inode_flag(fi, FI_INLINE_XATTR);
395 
396 	/* Will be used by directory only */
397 	fi->i_dir_level = F2FS_SB(sb)->dir_level;
398 
399 	return &fi->vfs_inode;
400 }
401 
402 static int f2fs_drop_inode(struct inode *inode)
403 {
404 	/*
405 	 * This is to avoid a deadlock condition like below.
406 	 * writeback_single_inode(inode)
407 	 *  - f2fs_write_data_page
408 	 *    - f2fs_gc -> iput -> evict
409 	 *       - inode_wait_for_writeback(inode)
410 	 */
411 	if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
412 		return 0;
413 	return generic_drop_inode(inode);
414 }
415 
416 /*
417  * f2fs_dirty_inode() is called from __mark_inode_dirty()
418  *
419  * We should call set_dirty_inode to write the dirty inode through write_inode.
420  */
421 static void f2fs_dirty_inode(struct inode *inode, int flags)
422 {
423 	set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
424 }
425 
426 static void f2fs_i_callback(struct rcu_head *head)
427 {
428 	struct inode *inode = container_of(head, struct inode, i_rcu);
429 	kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
430 }
431 
432 static void f2fs_destroy_inode(struct inode *inode)
433 {
434 	call_rcu(&inode->i_rcu, f2fs_i_callback);
435 }
436 
437 static void f2fs_put_super(struct super_block *sb)
438 {
439 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
440 
441 	if (sbi->s_proc) {
442 		remove_proc_entry("segment_info", sbi->s_proc);
443 		remove_proc_entry(sb->s_id, f2fs_proc_root);
444 	}
445 	kobject_del(&sbi->s_kobj);
446 
447 	f2fs_destroy_stats(sbi);
448 	stop_gc_thread(sbi);
449 
450 	/*
451 	 * We don't need to do checkpoint when superblock is clean.
452 	 * But, the previous checkpoint was not done by umount, it needs to do
453 	 * clean checkpoint again.
454 	 */
455 	if (is_sbi_flag_set(sbi, SBI_IS_DIRTY) ||
456 			!is_set_ckpt_flags(F2FS_CKPT(sbi), CP_UMOUNT_FLAG)) {
457 		struct cp_control cpc = {
458 			.reason = CP_UMOUNT,
459 		};
460 		write_checkpoint(sbi, &cpc);
461 	}
462 
463 	/*
464 	 * normally superblock is clean, so we need to release this.
465 	 * In addition, EIO will skip do checkpoint, we need this as well.
466 	 */
467 	release_dirty_inode(sbi);
468 	release_discard_addrs(sbi);
469 
470 	iput(sbi->node_inode);
471 	iput(sbi->meta_inode);
472 
473 	/* destroy f2fs internal modules */
474 	destroy_node_manager(sbi);
475 	destroy_segment_manager(sbi);
476 
477 	kfree(sbi->ckpt);
478 	kobject_put(&sbi->s_kobj);
479 	wait_for_completion(&sbi->s_kobj_unregister);
480 
481 	sb->s_fs_info = NULL;
482 	brelse(sbi->raw_super_buf);
483 	kfree(sbi);
484 }
485 
486 int f2fs_sync_fs(struct super_block *sb, int sync)
487 {
488 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
489 
490 	trace_f2fs_sync_fs(sb, sync);
491 
492 	if (sync) {
493 		struct cp_control cpc;
494 
495 		cpc.reason = (test_opt(sbi, FASTBOOT) ||
496 					is_sbi_flag_set(sbi, SBI_IS_CLOSE)) ?
497 						CP_UMOUNT : CP_SYNC;
498 		mutex_lock(&sbi->gc_mutex);
499 		write_checkpoint(sbi, &cpc);
500 		mutex_unlock(&sbi->gc_mutex);
501 	} else {
502 		f2fs_balance_fs(sbi);
503 	}
504 	f2fs_trace_ios(NULL, NULL, 1);
505 
506 	return 0;
507 }
508 
509 static int f2fs_freeze(struct super_block *sb)
510 {
511 	int err;
512 
513 	if (f2fs_readonly(sb))
514 		return 0;
515 
516 	err = f2fs_sync_fs(sb, 1);
517 	return err;
518 }
519 
520 static int f2fs_unfreeze(struct super_block *sb)
521 {
522 	return 0;
523 }
524 
525 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
526 {
527 	struct super_block *sb = dentry->d_sb;
528 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
529 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
530 	block_t total_count, user_block_count, start_count, ovp_count;
531 
532 	total_count = le64_to_cpu(sbi->raw_super->block_count);
533 	user_block_count = sbi->user_block_count;
534 	start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
535 	ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
536 	buf->f_type = F2FS_SUPER_MAGIC;
537 	buf->f_bsize = sbi->blocksize;
538 
539 	buf->f_blocks = total_count - start_count;
540 	buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
541 	buf->f_bavail = user_block_count - valid_user_blocks(sbi);
542 
543 	buf->f_files = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
544 	buf->f_ffree = buf->f_files - valid_inode_count(sbi);
545 
546 	buf->f_namelen = F2FS_NAME_LEN;
547 	buf->f_fsid.val[0] = (u32)id;
548 	buf->f_fsid.val[1] = (u32)(id >> 32);
549 
550 	return 0;
551 }
552 
553 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
554 {
555 	struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
556 
557 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC))
558 		seq_printf(seq, ",background_gc=%s", "on");
559 	else
560 		seq_printf(seq, ",background_gc=%s", "off");
561 	if (test_opt(sbi, DISABLE_ROLL_FORWARD))
562 		seq_puts(seq, ",disable_roll_forward");
563 	if (test_opt(sbi, DISCARD))
564 		seq_puts(seq, ",discard");
565 	if (test_opt(sbi, NOHEAP))
566 		seq_puts(seq, ",no_heap_alloc");
567 #ifdef CONFIG_F2FS_FS_XATTR
568 	if (test_opt(sbi, XATTR_USER))
569 		seq_puts(seq, ",user_xattr");
570 	else
571 		seq_puts(seq, ",nouser_xattr");
572 	if (test_opt(sbi, INLINE_XATTR))
573 		seq_puts(seq, ",inline_xattr");
574 #endif
575 #ifdef CONFIG_F2FS_FS_POSIX_ACL
576 	if (test_opt(sbi, POSIX_ACL))
577 		seq_puts(seq, ",acl");
578 	else
579 		seq_puts(seq, ",noacl");
580 #endif
581 	if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
582 		seq_puts(seq, ",disable_ext_identify");
583 	if (test_opt(sbi, INLINE_DATA))
584 		seq_puts(seq, ",inline_data");
585 	if (test_opt(sbi, INLINE_DENTRY))
586 		seq_puts(seq, ",inline_dentry");
587 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
588 		seq_puts(seq, ",flush_merge");
589 	if (test_opt(sbi, NOBARRIER))
590 		seq_puts(seq, ",nobarrier");
591 	if (test_opt(sbi, FASTBOOT))
592 		seq_puts(seq, ",fastboot");
593 	seq_printf(seq, ",active_logs=%u", sbi->active_logs);
594 
595 	return 0;
596 }
597 
598 static int segment_info_seq_show(struct seq_file *seq, void *offset)
599 {
600 	struct super_block *sb = seq->private;
601 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
602 	unsigned int total_segs =
603 			le32_to_cpu(sbi->raw_super->segment_count_main);
604 	int i;
605 
606 	seq_puts(seq, "format: segment_type|valid_blocks\n"
607 		"segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
608 
609 	for (i = 0; i < total_segs; i++) {
610 		struct seg_entry *se = get_seg_entry(sbi, i);
611 
612 		if ((i % 10) == 0)
613 			seq_printf(seq, "%-5d", i);
614 		seq_printf(seq, "%d|%-3u", se->type,
615 					get_valid_blocks(sbi, i, 1));
616 		if ((i % 10) == 9 || i == (total_segs - 1))
617 			seq_putc(seq, '\n');
618 		else
619 			seq_putc(seq, ' ');
620 	}
621 
622 	return 0;
623 }
624 
625 static int segment_info_open_fs(struct inode *inode, struct file *file)
626 {
627 	return single_open(file, segment_info_seq_show, PDE_DATA(inode));
628 }
629 
630 static const struct file_operations f2fs_seq_segment_info_fops = {
631 	.owner = THIS_MODULE,
632 	.open = segment_info_open_fs,
633 	.read = seq_read,
634 	.llseek = seq_lseek,
635 	.release = single_release,
636 };
637 
638 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
639 {
640 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
641 	struct f2fs_mount_info org_mount_opt;
642 	int err, active_logs;
643 	bool need_restart_gc = false;
644 	bool need_stop_gc = false;
645 
646 	sync_filesystem(sb);
647 
648 	/*
649 	 * Save the old mount options in case we
650 	 * need to restore them.
651 	 */
652 	org_mount_opt = sbi->mount_opt;
653 	active_logs = sbi->active_logs;
654 
655 	sbi->mount_opt.opt = 0;
656 	sbi->active_logs = NR_CURSEG_TYPE;
657 
658 	/* parse mount options */
659 	err = parse_options(sb, data);
660 	if (err)
661 		goto restore_opts;
662 
663 	/*
664 	 * Previous and new state of filesystem is RO,
665 	 * so skip checking GC and FLUSH_MERGE conditions.
666 	 */
667 	if (f2fs_readonly(sb) && (*flags & MS_RDONLY))
668 		goto skip;
669 
670 	/*
671 	 * We stop the GC thread if FS is mounted as RO
672 	 * or if background_gc = off is passed in mount
673 	 * option. Also sync the filesystem.
674 	 */
675 	if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
676 		if (sbi->gc_thread) {
677 			stop_gc_thread(sbi);
678 			f2fs_sync_fs(sb, 1);
679 			need_restart_gc = true;
680 		}
681 	} else if (!sbi->gc_thread) {
682 		err = start_gc_thread(sbi);
683 		if (err)
684 			goto restore_opts;
685 		need_stop_gc = true;
686 	}
687 
688 	/*
689 	 * We stop issue flush thread if FS is mounted as RO
690 	 * or if flush_merge is not passed in mount option.
691 	 */
692 	if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
693 		destroy_flush_cmd_control(sbi);
694 	} else if (!SM_I(sbi)->cmd_control_info) {
695 		err = create_flush_cmd_control(sbi);
696 		if (err)
697 			goto restore_gc;
698 	}
699 skip:
700 	/* Update the POSIXACL Flag */
701 	 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
702 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
703 	return 0;
704 restore_gc:
705 	if (need_restart_gc) {
706 		if (start_gc_thread(sbi))
707 			f2fs_msg(sbi->sb, KERN_WARNING,
708 				"background gc thread has stopped");
709 	} else if (need_stop_gc) {
710 		stop_gc_thread(sbi);
711 	}
712 restore_opts:
713 	sbi->mount_opt = org_mount_opt;
714 	sbi->active_logs = active_logs;
715 	return err;
716 }
717 
718 static struct super_operations f2fs_sops = {
719 	.alloc_inode	= f2fs_alloc_inode,
720 	.drop_inode	= f2fs_drop_inode,
721 	.destroy_inode	= f2fs_destroy_inode,
722 	.write_inode	= f2fs_write_inode,
723 	.dirty_inode	= f2fs_dirty_inode,
724 	.show_options	= f2fs_show_options,
725 	.evict_inode	= f2fs_evict_inode,
726 	.put_super	= f2fs_put_super,
727 	.sync_fs	= f2fs_sync_fs,
728 	.freeze_fs	= f2fs_freeze,
729 	.unfreeze_fs	= f2fs_unfreeze,
730 	.statfs		= f2fs_statfs,
731 	.remount_fs	= f2fs_remount,
732 };
733 
734 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
735 		u64 ino, u32 generation)
736 {
737 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
738 	struct inode *inode;
739 
740 	if (check_nid_range(sbi, ino))
741 		return ERR_PTR(-ESTALE);
742 
743 	/*
744 	 * f2fs_iget isn't quite right if the inode is currently unallocated!
745 	 * However f2fs_iget currently does appropriate checks to handle stale
746 	 * inodes so everything is OK.
747 	 */
748 	inode = f2fs_iget(sb, ino);
749 	if (IS_ERR(inode))
750 		return ERR_CAST(inode);
751 	if (unlikely(generation && inode->i_generation != generation)) {
752 		/* we didn't find the right inode.. */
753 		iput(inode);
754 		return ERR_PTR(-ESTALE);
755 	}
756 	return inode;
757 }
758 
759 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
760 		int fh_len, int fh_type)
761 {
762 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
763 				    f2fs_nfs_get_inode);
764 }
765 
766 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
767 		int fh_len, int fh_type)
768 {
769 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
770 				    f2fs_nfs_get_inode);
771 }
772 
773 static const struct export_operations f2fs_export_ops = {
774 	.fh_to_dentry = f2fs_fh_to_dentry,
775 	.fh_to_parent = f2fs_fh_to_parent,
776 	.get_parent = f2fs_get_parent,
777 };
778 
779 static loff_t max_file_size(unsigned bits)
780 {
781 	loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
782 	loff_t leaf_count = ADDRS_PER_BLOCK;
783 
784 	/* two direct node blocks */
785 	result += (leaf_count * 2);
786 
787 	/* two indirect node blocks */
788 	leaf_count *= NIDS_PER_BLOCK;
789 	result += (leaf_count * 2);
790 
791 	/* one double indirect node block */
792 	leaf_count *= NIDS_PER_BLOCK;
793 	result += leaf_count;
794 
795 	result <<= bits;
796 	return result;
797 }
798 
799 static int sanity_check_raw_super(struct super_block *sb,
800 			struct f2fs_super_block *raw_super)
801 {
802 	unsigned int blocksize;
803 
804 	if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
805 		f2fs_msg(sb, KERN_INFO,
806 			"Magic Mismatch, valid(0x%x) - read(0x%x)",
807 			F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
808 		return 1;
809 	}
810 
811 	/* Currently, support only 4KB page cache size */
812 	if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
813 		f2fs_msg(sb, KERN_INFO,
814 			"Invalid page_cache_size (%lu), supports only 4KB\n",
815 			PAGE_CACHE_SIZE);
816 		return 1;
817 	}
818 
819 	/* Currently, support only 4KB block size */
820 	blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
821 	if (blocksize != F2FS_BLKSIZE) {
822 		f2fs_msg(sb, KERN_INFO,
823 			"Invalid blocksize (%u), supports only 4KB\n",
824 			blocksize);
825 		return 1;
826 	}
827 
828 	/* Currently, support 512/1024/2048/4096 bytes sector size */
829 	if (le32_to_cpu(raw_super->log_sectorsize) >
830 				F2FS_MAX_LOG_SECTOR_SIZE ||
831 		le32_to_cpu(raw_super->log_sectorsize) <
832 				F2FS_MIN_LOG_SECTOR_SIZE) {
833 		f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize (%u)",
834 			le32_to_cpu(raw_super->log_sectorsize));
835 		return 1;
836 	}
837 	if (le32_to_cpu(raw_super->log_sectors_per_block) +
838 		le32_to_cpu(raw_super->log_sectorsize) !=
839 			F2FS_MAX_LOG_SECTOR_SIZE) {
840 		f2fs_msg(sb, KERN_INFO,
841 			"Invalid log sectors per block(%u) log sectorsize(%u)",
842 			le32_to_cpu(raw_super->log_sectors_per_block),
843 			le32_to_cpu(raw_super->log_sectorsize));
844 		return 1;
845 	}
846 	return 0;
847 }
848 
849 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
850 {
851 	unsigned int total, fsmeta;
852 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
853 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
854 
855 	total = le32_to_cpu(raw_super->segment_count);
856 	fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
857 	fsmeta += le32_to_cpu(raw_super->segment_count_sit);
858 	fsmeta += le32_to_cpu(raw_super->segment_count_nat);
859 	fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
860 	fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
861 
862 	if (unlikely(fsmeta >= total))
863 		return 1;
864 
865 	if (unlikely(f2fs_cp_error(sbi))) {
866 		f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
867 		return 1;
868 	}
869 	return 0;
870 }
871 
872 static void init_sb_info(struct f2fs_sb_info *sbi)
873 {
874 	struct f2fs_super_block *raw_super = sbi->raw_super;
875 	int i;
876 
877 	sbi->log_sectors_per_block =
878 		le32_to_cpu(raw_super->log_sectors_per_block);
879 	sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
880 	sbi->blocksize = 1 << sbi->log_blocksize;
881 	sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
882 	sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
883 	sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
884 	sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
885 	sbi->total_sections = le32_to_cpu(raw_super->section_count);
886 	sbi->total_node_count =
887 		(le32_to_cpu(raw_super->segment_count_nat) / 2)
888 			* sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
889 	sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
890 	sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
891 	sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
892 	sbi->cur_victim_sec = NULL_SECNO;
893 	sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
894 
895 	for (i = 0; i < NR_COUNT_TYPE; i++)
896 		atomic_set(&sbi->nr_pages[i], 0);
897 
898 	sbi->dir_level = DEF_DIR_LEVEL;
899 	clear_sbi_flag(sbi, SBI_NEED_FSCK);
900 }
901 
902 /*
903  * Read f2fs raw super block.
904  * Because we have two copies of super block, so read the first one at first,
905  * if the first one is invalid, move to read the second one.
906  */
907 static int read_raw_super_block(struct super_block *sb,
908 			struct f2fs_super_block **raw_super,
909 			struct buffer_head **raw_super_buf)
910 {
911 	int block = 0;
912 
913 retry:
914 	*raw_super_buf = sb_bread(sb, block);
915 	if (!*raw_super_buf) {
916 		f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
917 				block + 1);
918 		if (block == 0) {
919 			block++;
920 			goto retry;
921 		} else {
922 			return -EIO;
923 		}
924 	}
925 
926 	*raw_super = (struct f2fs_super_block *)
927 		((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
928 
929 	/* sanity checking of raw super */
930 	if (sanity_check_raw_super(sb, *raw_super)) {
931 		brelse(*raw_super_buf);
932 		f2fs_msg(sb, KERN_ERR,
933 			"Can't find valid F2FS filesystem in %dth superblock",
934 								block + 1);
935 		if (block == 0) {
936 			block++;
937 			goto retry;
938 		} else {
939 			return -EINVAL;
940 		}
941 	}
942 
943 	return 0;
944 }
945 
946 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
947 {
948 	struct f2fs_sb_info *sbi;
949 	struct f2fs_super_block *raw_super = NULL;
950 	struct buffer_head *raw_super_buf;
951 	struct inode *root;
952 	long err = -EINVAL;
953 	bool retry = true;
954 	int i;
955 
956 try_onemore:
957 	/* allocate memory for f2fs-specific super block info */
958 	sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
959 	if (!sbi)
960 		return -ENOMEM;
961 
962 	/* set a block size */
963 	if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
964 		f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
965 		goto free_sbi;
966 	}
967 
968 	err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
969 	if (err)
970 		goto free_sbi;
971 
972 	sb->s_fs_info = sbi;
973 	/* init some FS parameters */
974 	sbi->active_logs = NR_CURSEG_TYPE;
975 
976 	set_opt(sbi, BG_GC);
977 
978 #ifdef CONFIG_F2FS_FS_XATTR
979 	set_opt(sbi, XATTR_USER);
980 #endif
981 #ifdef CONFIG_F2FS_FS_POSIX_ACL
982 	set_opt(sbi, POSIX_ACL);
983 #endif
984 	/* parse mount options */
985 	err = parse_options(sb, (char *)data);
986 	if (err)
987 		goto free_sb_buf;
988 
989 	sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
990 	sb->s_max_links = F2FS_LINK_MAX;
991 	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
992 
993 	sb->s_op = &f2fs_sops;
994 	sb->s_xattr = f2fs_xattr_handlers;
995 	sb->s_export_op = &f2fs_export_ops;
996 	sb->s_magic = F2FS_SUPER_MAGIC;
997 	sb->s_time_gran = 1;
998 	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
999 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
1000 	memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
1001 
1002 	/* init f2fs-specific super block info */
1003 	sbi->sb = sb;
1004 	sbi->raw_super = raw_super;
1005 	sbi->raw_super_buf = raw_super_buf;
1006 	mutex_init(&sbi->gc_mutex);
1007 	mutex_init(&sbi->writepages);
1008 	mutex_init(&sbi->cp_mutex);
1009 	init_rwsem(&sbi->node_write);
1010 	clear_sbi_flag(sbi, SBI_POR_DOING);
1011 	spin_lock_init(&sbi->stat_lock);
1012 
1013 	init_rwsem(&sbi->read_io.io_rwsem);
1014 	sbi->read_io.sbi = sbi;
1015 	sbi->read_io.bio = NULL;
1016 	for (i = 0; i < NR_PAGE_TYPE; i++) {
1017 		init_rwsem(&sbi->write_io[i].io_rwsem);
1018 		sbi->write_io[i].sbi = sbi;
1019 		sbi->write_io[i].bio = NULL;
1020 	}
1021 
1022 	init_rwsem(&sbi->cp_rwsem);
1023 	init_waitqueue_head(&sbi->cp_wait);
1024 	init_sb_info(sbi);
1025 
1026 	/* get an inode for meta space */
1027 	sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
1028 	if (IS_ERR(sbi->meta_inode)) {
1029 		f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
1030 		err = PTR_ERR(sbi->meta_inode);
1031 		goto free_sb_buf;
1032 	}
1033 
1034 	err = get_valid_checkpoint(sbi);
1035 	if (err) {
1036 		f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
1037 		goto free_meta_inode;
1038 	}
1039 
1040 	/* sanity checking of checkpoint */
1041 	err = -EINVAL;
1042 	if (sanity_check_ckpt(sbi)) {
1043 		f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
1044 		goto free_cp;
1045 	}
1046 
1047 	sbi->total_valid_node_count =
1048 				le32_to_cpu(sbi->ckpt->valid_node_count);
1049 	sbi->total_valid_inode_count =
1050 				le32_to_cpu(sbi->ckpt->valid_inode_count);
1051 	sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
1052 	sbi->total_valid_block_count =
1053 				le64_to_cpu(sbi->ckpt->valid_block_count);
1054 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1055 	sbi->alloc_valid_block_count = 0;
1056 	INIT_LIST_HEAD(&sbi->dir_inode_list);
1057 	spin_lock_init(&sbi->dir_inode_lock);
1058 
1059 	init_ino_entry_info(sbi);
1060 
1061 	/* setup f2fs internal modules */
1062 	err = build_segment_manager(sbi);
1063 	if (err) {
1064 		f2fs_msg(sb, KERN_ERR,
1065 			"Failed to initialize F2FS segment manager");
1066 		goto free_sm;
1067 	}
1068 	err = build_node_manager(sbi);
1069 	if (err) {
1070 		f2fs_msg(sb, KERN_ERR,
1071 			"Failed to initialize F2FS node manager");
1072 		goto free_nm;
1073 	}
1074 
1075 	build_gc_manager(sbi);
1076 
1077 	/* get an inode for node space */
1078 	sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1079 	if (IS_ERR(sbi->node_inode)) {
1080 		f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1081 		err = PTR_ERR(sbi->node_inode);
1082 		goto free_nm;
1083 	}
1084 
1085 	/* if there are nt orphan nodes free them */
1086 	recover_orphan_inodes(sbi);
1087 
1088 	/* read root inode and dentry */
1089 	root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1090 	if (IS_ERR(root)) {
1091 		f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1092 		err = PTR_ERR(root);
1093 		goto free_node_inode;
1094 	}
1095 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1096 		iput(root);
1097 		err = -EINVAL;
1098 		goto free_node_inode;
1099 	}
1100 
1101 	sb->s_root = d_make_root(root); /* allocate root dentry */
1102 	if (!sb->s_root) {
1103 		err = -ENOMEM;
1104 		goto free_root_inode;
1105 	}
1106 
1107 	err = f2fs_build_stats(sbi);
1108 	if (err)
1109 		goto free_root_inode;
1110 
1111 	if (f2fs_proc_root)
1112 		sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1113 
1114 	if (sbi->s_proc)
1115 		proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1116 				 &f2fs_seq_segment_info_fops, sb);
1117 
1118 	if (test_opt(sbi, DISCARD)) {
1119 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1120 		if (!blk_queue_discard(q))
1121 			f2fs_msg(sb, KERN_WARNING,
1122 					"mounting with \"discard\" option, but "
1123 					"the device does not support discard");
1124 	}
1125 
1126 	sbi->s_kobj.kset = f2fs_kset;
1127 	init_completion(&sbi->s_kobj_unregister);
1128 	err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1129 							"%s", sb->s_id);
1130 	if (err)
1131 		goto free_proc;
1132 
1133 	if (!retry)
1134 		set_sbi_flag(sbi, SBI_NEED_FSCK);
1135 
1136 	/* recover fsynced data */
1137 	if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1138 		err = recover_fsync_data(sbi);
1139 		if (err) {
1140 			f2fs_msg(sb, KERN_ERR,
1141 				"Cannot recover all fsync data errno=%ld", err);
1142 			goto free_kobj;
1143 		}
1144 	}
1145 
1146 	/*
1147 	 * If filesystem is not mounted as read-only then
1148 	 * do start the gc_thread.
1149 	 */
1150 	if (test_opt(sbi, BG_GC) && !f2fs_readonly(sb)) {
1151 		/* After POR, we can run background GC thread.*/
1152 		err = start_gc_thread(sbi);
1153 		if (err)
1154 			goto free_kobj;
1155 	}
1156 	return 0;
1157 
1158 free_kobj:
1159 	kobject_del(&sbi->s_kobj);
1160 free_proc:
1161 	if (sbi->s_proc) {
1162 		remove_proc_entry("segment_info", sbi->s_proc);
1163 		remove_proc_entry(sb->s_id, f2fs_proc_root);
1164 	}
1165 	f2fs_destroy_stats(sbi);
1166 free_root_inode:
1167 	dput(sb->s_root);
1168 	sb->s_root = NULL;
1169 free_node_inode:
1170 	iput(sbi->node_inode);
1171 free_nm:
1172 	destroy_node_manager(sbi);
1173 free_sm:
1174 	destroy_segment_manager(sbi);
1175 free_cp:
1176 	kfree(sbi->ckpt);
1177 free_meta_inode:
1178 	make_bad_inode(sbi->meta_inode);
1179 	iput(sbi->meta_inode);
1180 free_sb_buf:
1181 	brelse(raw_super_buf);
1182 free_sbi:
1183 	kfree(sbi);
1184 
1185 	/* give only one another chance */
1186 	if (retry) {
1187 		retry = 0;
1188 		shrink_dcache_sb(sb);
1189 		goto try_onemore;
1190 	}
1191 	return err;
1192 }
1193 
1194 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1195 			const char *dev_name, void *data)
1196 {
1197 	return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1198 }
1199 
1200 static void kill_f2fs_super(struct super_block *sb)
1201 {
1202 	if (sb->s_root)
1203 		set_sbi_flag(F2FS_SB(sb), SBI_IS_CLOSE);
1204 	kill_block_super(sb);
1205 }
1206 
1207 static struct file_system_type f2fs_fs_type = {
1208 	.owner		= THIS_MODULE,
1209 	.name		= "f2fs",
1210 	.mount		= f2fs_mount,
1211 	.kill_sb	= kill_f2fs_super,
1212 	.fs_flags	= FS_REQUIRES_DEV,
1213 };
1214 MODULE_ALIAS_FS("f2fs");
1215 
1216 static int __init init_inodecache(void)
1217 {
1218 	f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1219 			sizeof(struct f2fs_inode_info));
1220 	if (!f2fs_inode_cachep)
1221 		return -ENOMEM;
1222 	return 0;
1223 }
1224 
1225 static void destroy_inodecache(void)
1226 {
1227 	/*
1228 	 * Make sure all delayed rcu free inodes are flushed before we
1229 	 * destroy cache.
1230 	 */
1231 	rcu_barrier();
1232 	kmem_cache_destroy(f2fs_inode_cachep);
1233 }
1234 
1235 static int __init init_f2fs_fs(void)
1236 {
1237 	int err;
1238 
1239 	f2fs_build_trace_ios();
1240 
1241 	err = init_inodecache();
1242 	if (err)
1243 		goto fail;
1244 	err = create_node_manager_caches();
1245 	if (err)
1246 		goto free_inodecache;
1247 	err = create_segment_manager_caches();
1248 	if (err)
1249 		goto free_node_manager_caches;
1250 	err = create_checkpoint_caches();
1251 	if (err)
1252 		goto free_segment_manager_caches;
1253 	f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1254 	if (!f2fs_kset) {
1255 		err = -ENOMEM;
1256 		goto free_checkpoint_caches;
1257 	}
1258 	err = register_filesystem(&f2fs_fs_type);
1259 	if (err)
1260 		goto free_kset;
1261 	f2fs_create_root_stats();
1262 	f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1263 	return 0;
1264 
1265 free_kset:
1266 	kset_unregister(f2fs_kset);
1267 free_checkpoint_caches:
1268 	destroy_checkpoint_caches();
1269 free_segment_manager_caches:
1270 	destroy_segment_manager_caches();
1271 free_node_manager_caches:
1272 	destroy_node_manager_caches();
1273 free_inodecache:
1274 	destroy_inodecache();
1275 fail:
1276 	return err;
1277 }
1278 
1279 static void __exit exit_f2fs_fs(void)
1280 {
1281 	remove_proc_entry("fs/f2fs", NULL);
1282 	f2fs_destroy_root_stats();
1283 	unregister_filesystem(&f2fs_fs_type);
1284 	destroy_checkpoint_caches();
1285 	destroy_segment_manager_caches();
1286 	destroy_node_manager_caches();
1287 	destroy_inodecache();
1288 	kset_unregister(f2fs_kset);
1289 	f2fs_destroy_trace_ios();
1290 }
1291 
1292 module_init(init_f2fs_fs)
1293 module_exit(exit_f2fs_fs)
1294 
1295 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1296 MODULE_DESCRIPTION("Flash Friendly File System");
1297 MODULE_LICENSE("GPL");
1298