xref: /openbmc/linux/fs/f2fs/super.c (revision 034f90b3)
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_norecovery,
46 	Opt_discard,
47 	Opt_noheap,
48 	Opt_user_xattr,
49 	Opt_nouser_xattr,
50 	Opt_acl,
51 	Opt_noacl,
52 	Opt_active_logs,
53 	Opt_disable_ext_identify,
54 	Opt_inline_xattr,
55 	Opt_inline_data,
56 	Opt_inline_dentry,
57 	Opt_flush_merge,
58 	Opt_nobarrier,
59 	Opt_fastboot,
60 	Opt_err,
61 };
62 
63 static match_table_t f2fs_tokens = {
64 	{Opt_gc_background, "background_gc=%s"},
65 	{Opt_disable_roll_forward, "disable_roll_forward"},
66 	{Opt_norecovery, "norecovery"},
67 	{Opt_discard, "discard"},
68 	{Opt_noheap, "no_heap"},
69 	{Opt_user_xattr, "user_xattr"},
70 	{Opt_nouser_xattr, "nouser_xattr"},
71 	{Opt_acl, "acl"},
72 	{Opt_noacl, "noacl"},
73 	{Opt_active_logs, "active_logs=%u"},
74 	{Opt_disable_ext_identify, "disable_ext_identify"},
75 	{Opt_inline_xattr, "inline_xattr"},
76 	{Opt_inline_data, "inline_data"},
77 	{Opt_inline_dentry, "inline_dentry"},
78 	{Opt_flush_merge, "flush_merge"},
79 	{Opt_nobarrier, "nobarrier"},
80 	{Opt_fastboot, "fastboot"},
81 	{Opt_err, NULL},
82 };
83 
84 /* Sysfs support for f2fs */
85 enum {
86 	GC_THREAD,	/* struct f2fs_gc_thread */
87 	SM_INFO,	/* struct f2fs_sm_info */
88 	NM_INFO,	/* struct f2fs_nm_info */
89 	F2FS_SBI,	/* struct f2fs_sb_info */
90 };
91 
92 struct f2fs_attr {
93 	struct attribute attr;
94 	ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
95 	ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
96 			 const char *, size_t);
97 	int struct_type;
98 	int offset;
99 };
100 
101 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
102 {
103 	if (struct_type == GC_THREAD)
104 		return (unsigned char *)sbi->gc_thread;
105 	else if (struct_type == SM_INFO)
106 		return (unsigned char *)SM_I(sbi);
107 	else if (struct_type == NM_INFO)
108 		return (unsigned char *)NM_I(sbi);
109 	else if (struct_type == F2FS_SBI)
110 		return (unsigned char *)sbi;
111 	return NULL;
112 }
113 
114 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
115 			struct f2fs_sb_info *sbi, char *buf)
116 {
117 	unsigned char *ptr = NULL;
118 	unsigned int *ui;
119 
120 	ptr = __struct_ptr(sbi, a->struct_type);
121 	if (!ptr)
122 		return -EINVAL;
123 
124 	ui = (unsigned int *)(ptr + a->offset);
125 
126 	return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
127 }
128 
129 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
130 			struct f2fs_sb_info *sbi,
131 			const char *buf, size_t count)
132 {
133 	unsigned char *ptr;
134 	unsigned long t;
135 	unsigned int *ui;
136 	ssize_t ret;
137 
138 	ptr = __struct_ptr(sbi, a->struct_type);
139 	if (!ptr)
140 		return -EINVAL;
141 
142 	ui = (unsigned int *)(ptr + a->offset);
143 
144 	ret = kstrtoul(skip_spaces(buf), 0, &t);
145 	if (ret < 0)
146 		return ret;
147 	*ui = t;
148 	return count;
149 }
150 
151 static ssize_t f2fs_attr_show(struct kobject *kobj,
152 				struct attribute *attr, char *buf)
153 {
154 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
155 								s_kobj);
156 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
157 
158 	return a->show ? a->show(a, sbi, buf) : 0;
159 }
160 
161 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
162 						const char *buf, size_t len)
163 {
164 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
165 									s_kobj);
166 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
167 
168 	return a->store ? a->store(a, sbi, buf, len) : 0;
169 }
170 
171 static void f2fs_sb_release(struct kobject *kobj)
172 {
173 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
174 								s_kobj);
175 	complete(&sbi->s_kobj_unregister);
176 }
177 
178 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
179 static struct f2fs_attr f2fs_attr_##_name = {			\
180 	.attr = {.name = __stringify(_name), .mode = _mode },	\
181 	.show	= _show,					\
182 	.store	= _store,					\
183 	.struct_type = _struct_type,				\
184 	.offset = _offset					\
185 }
186 
187 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)	\
188 	F2FS_ATTR_OFFSET(struct_type, name, 0644,		\
189 		f2fs_sbi_show, f2fs_sbi_store,			\
190 		offsetof(struct struct_name, elname))
191 
192 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
193 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
194 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
195 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
196 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
197 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
198 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, batched_trim_sections, trim_sections);
199 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
200 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
201 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks);
202 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
203 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
204 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
205 
206 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
207 static struct attribute *f2fs_attrs[] = {
208 	ATTR_LIST(gc_min_sleep_time),
209 	ATTR_LIST(gc_max_sleep_time),
210 	ATTR_LIST(gc_no_gc_sleep_time),
211 	ATTR_LIST(gc_idle),
212 	ATTR_LIST(reclaim_segments),
213 	ATTR_LIST(max_small_discards),
214 	ATTR_LIST(batched_trim_sections),
215 	ATTR_LIST(ipu_policy),
216 	ATTR_LIST(min_ipu_util),
217 	ATTR_LIST(min_fsync_blocks),
218 	ATTR_LIST(max_victim_search),
219 	ATTR_LIST(dir_level),
220 	ATTR_LIST(ram_thresh),
221 	NULL,
222 };
223 
224 static const struct sysfs_ops f2fs_attr_ops = {
225 	.show	= f2fs_attr_show,
226 	.store	= f2fs_attr_store,
227 };
228 
229 static struct kobj_type f2fs_ktype = {
230 	.default_attrs	= f2fs_attrs,
231 	.sysfs_ops	= &f2fs_attr_ops,
232 	.release	= f2fs_sb_release,
233 };
234 
235 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
236 {
237 	struct va_format vaf;
238 	va_list args;
239 
240 	va_start(args, fmt);
241 	vaf.fmt = fmt;
242 	vaf.va = &args;
243 	printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
244 	va_end(args);
245 }
246 
247 static void init_once(void *foo)
248 {
249 	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
250 
251 	inode_init_once(&fi->vfs_inode);
252 }
253 
254 static int parse_options(struct super_block *sb, char *options)
255 {
256 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
257 	substring_t args[MAX_OPT_ARGS];
258 	char *p, *name;
259 	int arg = 0;
260 
261 	if (!options)
262 		return 0;
263 
264 	while ((p = strsep(&options, ",")) != NULL) {
265 		int token;
266 		if (!*p)
267 			continue;
268 		/*
269 		 * Initialize args struct so we know whether arg was
270 		 * found; some options take optional arguments.
271 		 */
272 		args[0].to = args[0].from = NULL;
273 		token = match_token(p, f2fs_tokens, args);
274 
275 		switch (token) {
276 		case Opt_gc_background:
277 			name = match_strdup(&args[0]);
278 
279 			if (!name)
280 				return -ENOMEM;
281 			if (strlen(name) == 2 && !strncmp(name, "on", 2))
282 				set_opt(sbi, BG_GC);
283 			else if (strlen(name) == 3 && !strncmp(name, "off", 3))
284 				clear_opt(sbi, BG_GC);
285 			else {
286 				kfree(name);
287 				return -EINVAL;
288 			}
289 			kfree(name);
290 			break;
291 		case Opt_disable_roll_forward:
292 			set_opt(sbi, DISABLE_ROLL_FORWARD);
293 			break;
294 		case Opt_norecovery:
295 			/* this option mounts f2fs with ro */
296 			set_opt(sbi, DISABLE_ROLL_FORWARD);
297 			if (!f2fs_readonly(sb))
298 				return -EINVAL;
299 			break;
300 		case Opt_discard:
301 			set_opt(sbi, DISCARD);
302 			break;
303 		case Opt_noheap:
304 			set_opt(sbi, NOHEAP);
305 			break;
306 #ifdef CONFIG_F2FS_FS_XATTR
307 		case Opt_user_xattr:
308 			set_opt(sbi, XATTR_USER);
309 			break;
310 		case Opt_nouser_xattr:
311 			clear_opt(sbi, XATTR_USER);
312 			break;
313 		case Opt_inline_xattr:
314 			set_opt(sbi, INLINE_XATTR);
315 			break;
316 #else
317 		case Opt_user_xattr:
318 			f2fs_msg(sb, KERN_INFO,
319 				"user_xattr options not supported");
320 			break;
321 		case Opt_nouser_xattr:
322 			f2fs_msg(sb, KERN_INFO,
323 				"nouser_xattr options not supported");
324 			break;
325 		case Opt_inline_xattr:
326 			f2fs_msg(sb, KERN_INFO,
327 				"inline_xattr options not supported");
328 			break;
329 #endif
330 #ifdef CONFIG_F2FS_FS_POSIX_ACL
331 		case Opt_acl:
332 			set_opt(sbi, POSIX_ACL);
333 			break;
334 		case Opt_noacl:
335 			clear_opt(sbi, POSIX_ACL);
336 			break;
337 #else
338 		case Opt_acl:
339 			f2fs_msg(sb, KERN_INFO, "acl options not supported");
340 			break;
341 		case Opt_noacl:
342 			f2fs_msg(sb, KERN_INFO, "noacl options not supported");
343 			break;
344 #endif
345 		case Opt_active_logs:
346 			if (args->from && match_int(args, &arg))
347 				return -EINVAL;
348 			if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
349 				return -EINVAL;
350 			sbi->active_logs = arg;
351 			break;
352 		case Opt_disable_ext_identify:
353 			set_opt(sbi, DISABLE_EXT_IDENTIFY);
354 			break;
355 		case Opt_inline_data:
356 			set_opt(sbi, INLINE_DATA);
357 			break;
358 		case Opt_inline_dentry:
359 			set_opt(sbi, INLINE_DENTRY);
360 			break;
361 		case Opt_flush_merge:
362 			set_opt(sbi, FLUSH_MERGE);
363 			break;
364 		case Opt_nobarrier:
365 			set_opt(sbi, NOBARRIER);
366 			break;
367 		case Opt_fastboot:
368 			set_opt(sbi, FASTBOOT);
369 			break;
370 		default:
371 			f2fs_msg(sb, KERN_ERR,
372 				"Unrecognized mount option \"%s\" or missing value",
373 				p);
374 			return -EINVAL;
375 		}
376 	}
377 	return 0;
378 }
379 
380 static struct inode *f2fs_alloc_inode(struct super_block *sb)
381 {
382 	struct f2fs_inode_info *fi;
383 
384 	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
385 	if (!fi)
386 		return NULL;
387 
388 	init_once((void *) fi);
389 
390 	/* Initialize f2fs-specific inode info */
391 	fi->vfs_inode.i_version = 1;
392 	atomic_set(&fi->dirty_pages, 0);
393 	fi->i_current_depth = 1;
394 	fi->i_advise = 0;
395 	rwlock_init(&fi->ext.ext_lock);
396 	init_rwsem(&fi->i_sem);
397 	INIT_RADIX_TREE(&fi->inmem_root, GFP_NOFS);
398 	INIT_LIST_HEAD(&fi->inmem_pages);
399 	mutex_init(&fi->inmem_lock);
400 
401 	set_inode_flag(fi, FI_NEW_INODE);
402 
403 	if (test_opt(F2FS_SB(sb), INLINE_XATTR))
404 		set_inode_flag(fi, FI_INLINE_XATTR);
405 
406 	/* Will be used by directory only */
407 	fi->i_dir_level = F2FS_SB(sb)->dir_level;
408 
409 	return &fi->vfs_inode;
410 }
411 
412 static int f2fs_drop_inode(struct inode *inode)
413 {
414 	/*
415 	 * This is to avoid a deadlock condition like below.
416 	 * writeback_single_inode(inode)
417 	 *  - f2fs_write_data_page
418 	 *    - f2fs_gc -> iput -> evict
419 	 *       - inode_wait_for_writeback(inode)
420 	 */
421 	if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
422 		return 0;
423 	return generic_drop_inode(inode);
424 }
425 
426 /*
427  * f2fs_dirty_inode() is called from __mark_inode_dirty()
428  *
429  * We should call set_dirty_inode to write the dirty inode through write_inode.
430  */
431 static void f2fs_dirty_inode(struct inode *inode, int flags)
432 {
433 	set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
434 }
435 
436 static void f2fs_i_callback(struct rcu_head *head)
437 {
438 	struct inode *inode = container_of(head, struct inode, i_rcu);
439 	kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
440 }
441 
442 static void f2fs_destroy_inode(struct inode *inode)
443 {
444 	call_rcu(&inode->i_rcu, f2fs_i_callback);
445 }
446 
447 static void f2fs_put_super(struct super_block *sb)
448 {
449 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
450 
451 	if (sbi->s_proc) {
452 		remove_proc_entry("segment_info", sbi->s_proc);
453 		remove_proc_entry(sb->s_id, f2fs_proc_root);
454 	}
455 	kobject_del(&sbi->s_kobj);
456 
457 	f2fs_destroy_stats(sbi);
458 	stop_gc_thread(sbi);
459 
460 	/*
461 	 * We don't need to do checkpoint when superblock is clean.
462 	 * But, the previous checkpoint was not done by umount, it needs to do
463 	 * clean checkpoint again.
464 	 */
465 	if (is_sbi_flag_set(sbi, SBI_IS_DIRTY) ||
466 			!is_set_ckpt_flags(F2FS_CKPT(sbi), CP_UMOUNT_FLAG)) {
467 		struct cp_control cpc = {
468 			.reason = CP_UMOUNT,
469 		};
470 		write_checkpoint(sbi, &cpc);
471 	}
472 
473 	/*
474 	 * normally superblock is clean, so we need to release this.
475 	 * In addition, EIO will skip do checkpoint, we need this as well.
476 	 */
477 	release_dirty_inode(sbi);
478 	release_discard_addrs(sbi);
479 
480 	iput(sbi->node_inode);
481 	iput(sbi->meta_inode);
482 
483 	/* destroy f2fs internal modules */
484 	destroy_node_manager(sbi);
485 	destroy_segment_manager(sbi);
486 
487 	kfree(sbi->ckpt);
488 	kobject_put(&sbi->s_kobj);
489 	wait_for_completion(&sbi->s_kobj_unregister);
490 
491 	sb->s_fs_info = NULL;
492 	brelse(sbi->raw_super_buf);
493 	kfree(sbi);
494 }
495 
496 int f2fs_sync_fs(struct super_block *sb, int sync)
497 {
498 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
499 
500 	trace_f2fs_sync_fs(sb, sync);
501 
502 	if (sync) {
503 		struct cp_control cpc;
504 
505 		cpc.reason = __get_cp_reason(sbi);
506 
507 		mutex_lock(&sbi->gc_mutex);
508 		write_checkpoint(sbi, &cpc);
509 		mutex_unlock(&sbi->gc_mutex);
510 	} else {
511 		f2fs_balance_fs(sbi);
512 	}
513 	f2fs_trace_ios(NULL, NULL, 1);
514 
515 	return 0;
516 }
517 
518 static int f2fs_freeze(struct super_block *sb)
519 {
520 	int err;
521 
522 	if (f2fs_readonly(sb))
523 		return 0;
524 
525 	err = f2fs_sync_fs(sb, 1);
526 	return err;
527 }
528 
529 static int f2fs_unfreeze(struct super_block *sb)
530 {
531 	return 0;
532 }
533 
534 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
535 {
536 	struct super_block *sb = dentry->d_sb;
537 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
538 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
539 	block_t total_count, user_block_count, start_count, ovp_count;
540 
541 	total_count = le64_to_cpu(sbi->raw_super->block_count);
542 	user_block_count = sbi->user_block_count;
543 	start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
544 	ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
545 	buf->f_type = F2FS_SUPER_MAGIC;
546 	buf->f_bsize = sbi->blocksize;
547 
548 	buf->f_blocks = total_count - start_count;
549 	buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
550 	buf->f_bavail = user_block_count - valid_user_blocks(sbi);
551 
552 	buf->f_files = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
553 	buf->f_ffree = buf->f_files - valid_inode_count(sbi);
554 
555 	buf->f_namelen = F2FS_NAME_LEN;
556 	buf->f_fsid.val[0] = (u32)id;
557 	buf->f_fsid.val[1] = (u32)(id >> 32);
558 
559 	return 0;
560 }
561 
562 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
563 {
564 	struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
565 
566 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC))
567 		seq_printf(seq, ",background_gc=%s", "on");
568 	else
569 		seq_printf(seq, ",background_gc=%s", "off");
570 	if (test_opt(sbi, DISABLE_ROLL_FORWARD))
571 		seq_puts(seq, ",disable_roll_forward");
572 	if (test_opt(sbi, DISCARD))
573 		seq_puts(seq, ",discard");
574 	if (test_opt(sbi, NOHEAP))
575 		seq_puts(seq, ",no_heap_alloc");
576 #ifdef CONFIG_F2FS_FS_XATTR
577 	if (test_opt(sbi, XATTR_USER))
578 		seq_puts(seq, ",user_xattr");
579 	else
580 		seq_puts(seq, ",nouser_xattr");
581 	if (test_opt(sbi, INLINE_XATTR))
582 		seq_puts(seq, ",inline_xattr");
583 #endif
584 #ifdef CONFIG_F2FS_FS_POSIX_ACL
585 	if (test_opt(sbi, POSIX_ACL))
586 		seq_puts(seq, ",acl");
587 	else
588 		seq_puts(seq, ",noacl");
589 #endif
590 	if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
591 		seq_puts(seq, ",disable_ext_identify");
592 	if (test_opt(sbi, INLINE_DATA))
593 		seq_puts(seq, ",inline_data");
594 	if (test_opt(sbi, INLINE_DENTRY))
595 		seq_puts(seq, ",inline_dentry");
596 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
597 		seq_puts(seq, ",flush_merge");
598 	if (test_opt(sbi, NOBARRIER))
599 		seq_puts(seq, ",nobarrier");
600 	if (test_opt(sbi, FASTBOOT))
601 		seq_puts(seq, ",fastboot");
602 	seq_printf(seq, ",active_logs=%u", sbi->active_logs);
603 
604 	return 0;
605 }
606 
607 static int segment_info_seq_show(struct seq_file *seq, void *offset)
608 {
609 	struct super_block *sb = seq->private;
610 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
611 	unsigned int total_segs =
612 			le32_to_cpu(sbi->raw_super->segment_count_main);
613 	int i;
614 
615 	seq_puts(seq, "format: segment_type|valid_blocks\n"
616 		"segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
617 
618 	for (i = 0; i < total_segs; i++) {
619 		struct seg_entry *se = get_seg_entry(sbi, i);
620 
621 		if ((i % 10) == 0)
622 			seq_printf(seq, "%-5d", i);
623 		seq_printf(seq, "%d|%-3u", se->type,
624 					get_valid_blocks(sbi, i, 1));
625 		if ((i % 10) == 9 || i == (total_segs - 1))
626 			seq_putc(seq, '\n');
627 		else
628 			seq_putc(seq, ' ');
629 	}
630 
631 	return 0;
632 }
633 
634 static int segment_info_open_fs(struct inode *inode, struct file *file)
635 {
636 	return single_open(file, segment_info_seq_show, PDE_DATA(inode));
637 }
638 
639 static const struct file_operations f2fs_seq_segment_info_fops = {
640 	.owner = THIS_MODULE,
641 	.open = segment_info_open_fs,
642 	.read = seq_read,
643 	.llseek = seq_lseek,
644 	.release = single_release,
645 };
646 
647 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
648 {
649 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
650 	struct f2fs_mount_info org_mount_opt;
651 	int err, active_logs;
652 	bool need_restart_gc = false;
653 	bool need_stop_gc = false;
654 
655 	sync_filesystem(sb);
656 
657 	/*
658 	 * Save the old mount options in case we
659 	 * need to restore them.
660 	 */
661 	org_mount_opt = sbi->mount_opt;
662 	active_logs = sbi->active_logs;
663 
664 	sbi->mount_opt.opt = 0;
665 	sbi->active_logs = NR_CURSEG_TYPE;
666 
667 	/* parse mount options */
668 	err = parse_options(sb, data);
669 	if (err)
670 		goto restore_opts;
671 
672 	/*
673 	 * Previous and new state of filesystem is RO,
674 	 * so skip checking GC and FLUSH_MERGE conditions.
675 	 */
676 	if (f2fs_readonly(sb) && (*flags & MS_RDONLY))
677 		goto skip;
678 
679 	/*
680 	 * We stop the GC thread if FS is mounted as RO
681 	 * or if background_gc = off is passed in mount
682 	 * option. Also sync the filesystem.
683 	 */
684 	if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
685 		if (sbi->gc_thread) {
686 			stop_gc_thread(sbi);
687 			f2fs_sync_fs(sb, 1);
688 			need_restart_gc = true;
689 		}
690 	} else if (!sbi->gc_thread) {
691 		err = start_gc_thread(sbi);
692 		if (err)
693 			goto restore_opts;
694 		need_stop_gc = true;
695 	}
696 
697 	/*
698 	 * We stop issue flush thread if FS is mounted as RO
699 	 * or if flush_merge is not passed in mount option.
700 	 */
701 	if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
702 		destroy_flush_cmd_control(sbi);
703 	} else if (!SM_I(sbi)->cmd_control_info) {
704 		err = create_flush_cmd_control(sbi);
705 		if (err)
706 			goto restore_gc;
707 	}
708 skip:
709 	/* Update the POSIXACL Flag */
710 	 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
711 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
712 	return 0;
713 restore_gc:
714 	if (need_restart_gc) {
715 		if (start_gc_thread(sbi))
716 			f2fs_msg(sbi->sb, KERN_WARNING,
717 				"background gc thread has stopped");
718 	} else if (need_stop_gc) {
719 		stop_gc_thread(sbi);
720 	}
721 restore_opts:
722 	sbi->mount_opt = org_mount_opt;
723 	sbi->active_logs = active_logs;
724 	return err;
725 }
726 
727 static struct super_operations f2fs_sops = {
728 	.alloc_inode	= f2fs_alloc_inode,
729 	.drop_inode	= f2fs_drop_inode,
730 	.destroy_inode	= f2fs_destroy_inode,
731 	.write_inode	= f2fs_write_inode,
732 	.dirty_inode	= f2fs_dirty_inode,
733 	.show_options	= f2fs_show_options,
734 	.evict_inode	= f2fs_evict_inode,
735 	.put_super	= f2fs_put_super,
736 	.sync_fs	= f2fs_sync_fs,
737 	.freeze_fs	= f2fs_freeze,
738 	.unfreeze_fs	= f2fs_unfreeze,
739 	.statfs		= f2fs_statfs,
740 	.remount_fs	= f2fs_remount,
741 };
742 
743 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
744 		u64 ino, u32 generation)
745 {
746 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
747 	struct inode *inode;
748 
749 	if (check_nid_range(sbi, ino))
750 		return ERR_PTR(-ESTALE);
751 
752 	/*
753 	 * f2fs_iget isn't quite right if the inode is currently unallocated!
754 	 * However f2fs_iget currently does appropriate checks to handle stale
755 	 * inodes so everything is OK.
756 	 */
757 	inode = f2fs_iget(sb, ino);
758 	if (IS_ERR(inode))
759 		return ERR_CAST(inode);
760 	if (unlikely(generation && inode->i_generation != generation)) {
761 		/* we didn't find the right inode.. */
762 		iput(inode);
763 		return ERR_PTR(-ESTALE);
764 	}
765 	return inode;
766 }
767 
768 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
769 		int fh_len, int fh_type)
770 {
771 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
772 				    f2fs_nfs_get_inode);
773 }
774 
775 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
776 		int fh_len, int fh_type)
777 {
778 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
779 				    f2fs_nfs_get_inode);
780 }
781 
782 static const struct export_operations f2fs_export_ops = {
783 	.fh_to_dentry = f2fs_fh_to_dentry,
784 	.fh_to_parent = f2fs_fh_to_parent,
785 	.get_parent = f2fs_get_parent,
786 };
787 
788 static loff_t max_file_size(unsigned bits)
789 {
790 	loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
791 	loff_t leaf_count = ADDRS_PER_BLOCK;
792 
793 	/* two direct node blocks */
794 	result += (leaf_count * 2);
795 
796 	/* two indirect node blocks */
797 	leaf_count *= NIDS_PER_BLOCK;
798 	result += (leaf_count * 2);
799 
800 	/* one double indirect node block */
801 	leaf_count *= NIDS_PER_BLOCK;
802 	result += leaf_count;
803 
804 	result <<= bits;
805 	return result;
806 }
807 
808 static int sanity_check_raw_super(struct super_block *sb,
809 			struct f2fs_super_block *raw_super)
810 {
811 	unsigned int blocksize;
812 
813 	if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
814 		f2fs_msg(sb, KERN_INFO,
815 			"Magic Mismatch, valid(0x%x) - read(0x%x)",
816 			F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
817 		return 1;
818 	}
819 
820 	/* Currently, support only 4KB page cache size */
821 	if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
822 		f2fs_msg(sb, KERN_INFO,
823 			"Invalid page_cache_size (%lu), supports only 4KB\n",
824 			PAGE_CACHE_SIZE);
825 		return 1;
826 	}
827 
828 	/* Currently, support only 4KB block size */
829 	blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
830 	if (blocksize != F2FS_BLKSIZE) {
831 		f2fs_msg(sb, KERN_INFO,
832 			"Invalid blocksize (%u), supports only 4KB\n",
833 			blocksize);
834 		return 1;
835 	}
836 
837 	/* Currently, support 512/1024/2048/4096 bytes sector size */
838 	if (le32_to_cpu(raw_super->log_sectorsize) >
839 				F2FS_MAX_LOG_SECTOR_SIZE ||
840 		le32_to_cpu(raw_super->log_sectorsize) <
841 				F2FS_MIN_LOG_SECTOR_SIZE) {
842 		f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize (%u)",
843 			le32_to_cpu(raw_super->log_sectorsize));
844 		return 1;
845 	}
846 	if (le32_to_cpu(raw_super->log_sectors_per_block) +
847 		le32_to_cpu(raw_super->log_sectorsize) !=
848 			F2FS_MAX_LOG_SECTOR_SIZE) {
849 		f2fs_msg(sb, KERN_INFO,
850 			"Invalid log sectors per block(%u) log sectorsize(%u)",
851 			le32_to_cpu(raw_super->log_sectors_per_block),
852 			le32_to_cpu(raw_super->log_sectorsize));
853 		return 1;
854 	}
855 	return 0;
856 }
857 
858 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
859 {
860 	unsigned int total, fsmeta;
861 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
862 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
863 
864 	total = le32_to_cpu(raw_super->segment_count);
865 	fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
866 	fsmeta += le32_to_cpu(raw_super->segment_count_sit);
867 	fsmeta += le32_to_cpu(raw_super->segment_count_nat);
868 	fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
869 	fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
870 
871 	if (unlikely(fsmeta >= total))
872 		return 1;
873 
874 	if (unlikely(f2fs_cp_error(sbi))) {
875 		f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
876 		return 1;
877 	}
878 	return 0;
879 }
880 
881 static void init_sb_info(struct f2fs_sb_info *sbi)
882 {
883 	struct f2fs_super_block *raw_super = sbi->raw_super;
884 	int i;
885 
886 	sbi->log_sectors_per_block =
887 		le32_to_cpu(raw_super->log_sectors_per_block);
888 	sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
889 	sbi->blocksize = 1 << sbi->log_blocksize;
890 	sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
891 	sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
892 	sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
893 	sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
894 	sbi->total_sections = le32_to_cpu(raw_super->section_count);
895 	sbi->total_node_count =
896 		(le32_to_cpu(raw_super->segment_count_nat) / 2)
897 			* sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
898 	sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
899 	sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
900 	sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
901 	sbi->cur_victim_sec = NULL_SECNO;
902 	sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
903 
904 	for (i = 0; i < NR_COUNT_TYPE; i++)
905 		atomic_set(&sbi->nr_pages[i], 0);
906 
907 	sbi->dir_level = DEF_DIR_LEVEL;
908 	clear_sbi_flag(sbi, SBI_NEED_FSCK);
909 }
910 
911 /*
912  * Read f2fs raw super block.
913  * Because we have two copies of super block, so read the first one at first,
914  * if the first one is invalid, move to read the second one.
915  */
916 static int read_raw_super_block(struct super_block *sb,
917 			struct f2fs_super_block **raw_super,
918 			struct buffer_head **raw_super_buf)
919 {
920 	int block = 0;
921 
922 retry:
923 	*raw_super_buf = sb_bread(sb, block);
924 	if (!*raw_super_buf) {
925 		f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
926 				block + 1);
927 		if (block == 0) {
928 			block++;
929 			goto retry;
930 		} else {
931 			return -EIO;
932 		}
933 	}
934 
935 	*raw_super = (struct f2fs_super_block *)
936 		((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
937 
938 	/* sanity checking of raw super */
939 	if (sanity_check_raw_super(sb, *raw_super)) {
940 		brelse(*raw_super_buf);
941 		f2fs_msg(sb, KERN_ERR,
942 			"Can't find valid F2FS filesystem in %dth superblock",
943 								block + 1);
944 		if (block == 0) {
945 			block++;
946 			goto retry;
947 		} else {
948 			return -EINVAL;
949 		}
950 	}
951 
952 	return 0;
953 }
954 
955 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
956 {
957 	struct f2fs_sb_info *sbi;
958 	struct f2fs_super_block *raw_super = NULL;
959 	struct buffer_head *raw_super_buf;
960 	struct inode *root;
961 	long err = -EINVAL;
962 	bool retry = true;
963 	char *options = NULL;
964 	int i;
965 
966 try_onemore:
967 	/* allocate memory for f2fs-specific super block info */
968 	sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
969 	if (!sbi)
970 		return -ENOMEM;
971 
972 	/* set a block size */
973 	if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
974 		f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
975 		goto free_sbi;
976 	}
977 
978 	err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
979 	if (err)
980 		goto free_sbi;
981 
982 	sb->s_fs_info = sbi;
983 	/* init some FS parameters */
984 	sbi->active_logs = NR_CURSEG_TYPE;
985 
986 	set_opt(sbi, BG_GC);
987 
988 #ifdef CONFIG_F2FS_FS_XATTR
989 	set_opt(sbi, XATTR_USER);
990 #endif
991 #ifdef CONFIG_F2FS_FS_POSIX_ACL
992 	set_opt(sbi, POSIX_ACL);
993 #endif
994 	/* parse mount options */
995 	options = kstrdup((const char *)data, GFP_KERNEL);
996 	if (data && !options) {
997 		err = -ENOMEM;
998 		goto free_sb_buf;
999 	}
1000 
1001 	err = parse_options(sb, options);
1002 	if (err)
1003 		goto free_options;
1004 
1005 	sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
1006 	sb->s_max_links = F2FS_LINK_MAX;
1007 	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1008 
1009 	sb->s_op = &f2fs_sops;
1010 	sb->s_xattr = f2fs_xattr_handlers;
1011 	sb->s_export_op = &f2fs_export_ops;
1012 	sb->s_magic = F2FS_SUPER_MAGIC;
1013 	sb->s_time_gran = 1;
1014 	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1015 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
1016 	memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
1017 
1018 	/* init f2fs-specific super block info */
1019 	sbi->sb = sb;
1020 	sbi->raw_super = raw_super;
1021 	sbi->raw_super_buf = raw_super_buf;
1022 	mutex_init(&sbi->gc_mutex);
1023 	mutex_init(&sbi->writepages);
1024 	mutex_init(&sbi->cp_mutex);
1025 	init_rwsem(&sbi->node_write);
1026 	clear_sbi_flag(sbi, SBI_POR_DOING);
1027 	spin_lock_init(&sbi->stat_lock);
1028 
1029 	init_rwsem(&sbi->read_io.io_rwsem);
1030 	sbi->read_io.sbi = sbi;
1031 	sbi->read_io.bio = NULL;
1032 	for (i = 0; i < NR_PAGE_TYPE; i++) {
1033 		init_rwsem(&sbi->write_io[i].io_rwsem);
1034 		sbi->write_io[i].sbi = sbi;
1035 		sbi->write_io[i].bio = NULL;
1036 	}
1037 
1038 	init_rwsem(&sbi->cp_rwsem);
1039 	init_waitqueue_head(&sbi->cp_wait);
1040 	init_sb_info(sbi);
1041 
1042 	/* get an inode for meta space */
1043 	sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
1044 	if (IS_ERR(sbi->meta_inode)) {
1045 		f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
1046 		err = PTR_ERR(sbi->meta_inode);
1047 		goto free_options;
1048 	}
1049 
1050 	err = get_valid_checkpoint(sbi);
1051 	if (err) {
1052 		f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
1053 		goto free_meta_inode;
1054 	}
1055 
1056 	/* sanity checking of checkpoint */
1057 	err = -EINVAL;
1058 	if (sanity_check_ckpt(sbi)) {
1059 		f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
1060 		goto free_cp;
1061 	}
1062 
1063 	sbi->total_valid_node_count =
1064 				le32_to_cpu(sbi->ckpt->valid_node_count);
1065 	sbi->total_valid_inode_count =
1066 				le32_to_cpu(sbi->ckpt->valid_inode_count);
1067 	sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
1068 	sbi->total_valid_block_count =
1069 				le64_to_cpu(sbi->ckpt->valid_block_count);
1070 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1071 	sbi->alloc_valid_block_count = 0;
1072 	INIT_LIST_HEAD(&sbi->dir_inode_list);
1073 	spin_lock_init(&sbi->dir_inode_lock);
1074 
1075 	init_ino_entry_info(sbi);
1076 
1077 	/* setup f2fs internal modules */
1078 	err = build_segment_manager(sbi);
1079 	if (err) {
1080 		f2fs_msg(sb, KERN_ERR,
1081 			"Failed to initialize F2FS segment manager");
1082 		goto free_sm;
1083 	}
1084 	err = build_node_manager(sbi);
1085 	if (err) {
1086 		f2fs_msg(sb, KERN_ERR,
1087 			"Failed to initialize F2FS node manager");
1088 		goto free_nm;
1089 	}
1090 
1091 	build_gc_manager(sbi);
1092 
1093 	/* get an inode for node space */
1094 	sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1095 	if (IS_ERR(sbi->node_inode)) {
1096 		f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1097 		err = PTR_ERR(sbi->node_inode);
1098 		goto free_nm;
1099 	}
1100 
1101 	/* if there are nt orphan nodes free them */
1102 	recover_orphan_inodes(sbi);
1103 
1104 	/* read root inode and dentry */
1105 	root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1106 	if (IS_ERR(root)) {
1107 		f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1108 		err = PTR_ERR(root);
1109 		goto free_node_inode;
1110 	}
1111 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1112 		iput(root);
1113 		err = -EINVAL;
1114 		goto free_node_inode;
1115 	}
1116 
1117 	sb->s_root = d_make_root(root); /* allocate root dentry */
1118 	if (!sb->s_root) {
1119 		err = -ENOMEM;
1120 		goto free_root_inode;
1121 	}
1122 
1123 	err = f2fs_build_stats(sbi);
1124 	if (err)
1125 		goto free_root_inode;
1126 
1127 	if (f2fs_proc_root)
1128 		sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1129 
1130 	if (sbi->s_proc)
1131 		proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1132 				 &f2fs_seq_segment_info_fops, sb);
1133 
1134 	if (test_opt(sbi, DISCARD)) {
1135 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1136 		if (!blk_queue_discard(q))
1137 			f2fs_msg(sb, KERN_WARNING,
1138 					"mounting with \"discard\" option, but "
1139 					"the device does not support discard");
1140 	}
1141 
1142 	sbi->s_kobj.kset = f2fs_kset;
1143 	init_completion(&sbi->s_kobj_unregister);
1144 	err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1145 							"%s", sb->s_id);
1146 	if (err)
1147 		goto free_proc;
1148 
1149 	if (!retry)
1150 		set_sbi_flag(sbi, SBI_NEED_FSCK);
1151 
1152 	/* recover fsynced data */
1153 	if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1154 		/*
1155 		 * mount should be failed, when device has readonly mode, and
1156 		 * previous checkpoint was not done by clean system shutdown.
1157 		 */
1158 		if (bdev_read_only(sb->s_bdev) &&
1159 				!is_set_ckpt_flags(sbi->ckpt, CP_UMOUNT_FLAG)) {
1160 			err = -EROFS;
1161 			goto free_kobj;
1162 		}
1163 		err = recover_fsync_data(sbi);
1164 		if (err) {
1165 			f2fs_msg(sb, KERN_ERR,
1166 				"Cannot recover all fsync data errno=%ld", err);
1167 			goto free_kobj;
1168 		}
1169 	}
1170 
1171 	/*
1172 	 * If filesystem is not mounted as read-only then
1173 	 * do start the gc_thread.
1174 	 */
1175 	if (test_opt(sbi, BG_GC) && !f2fs_readonly(sb)) {
1176 		/* After POR, we can run background GC thread.*/
1177 		err = start_gc_thread(sbi);
1178 		if (err)
1179 			goto free_kobj;
1180 	}
1181 	kfree(options);
1182 	return 0;
1183 
1184 free_kobj:
1185 	kobject_del(&sbi->s_kobj);
1186 free_proc:
1187 	if (sbi->s_proc) {
1188 		remove_proc_entry("segment_info", sbi->s_proc);
1189 		remove_proc_entry(sb->s_id, f2fs_proc_root);
1190 	}
1191 	f2fs_destroy_stats(sbi);
1192 free_root_inode:
1193 	dput(sb->s_root);
1194 	sb->s_root = NULL;
1195 free_node_inode:
1196 	iput(sbi->node_inode);
1197 free_nm:
1198 	destroy_node_manager(sbi);
1199 free_sm:
1200 	destroy_segment_manager(sbi);
1201 free_cp:
1202 	kfree(sbi->ckpt);
1203 free_meta_inode:
1204 	make_bad_inode(sbi->meta_inode);
1205 	iput(sbi->meta_inode);
1206 free_options:
1207 	kfree(options);
1208 free_sb_buf:
1209 	brelse(raw_super_buf);
1210 free_sbi:
1211 	kfree(sbi);
1212 
1213 	/* give only one another chance */
1214 	if (retry) {
1215 		retry = 0;
1216 		shrink_dcache_sb(sb);
1217 		goto try_onemore;
1218 	}
1219 	return err;
1220 }
1221 
1222 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1223 			const char *dev_name, void *data)
1224 {
1225 	return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1226 }
1227 
1228 static void kill_f2fs_super(struct super_block *sb)
1229 {
1230 	if (sb->s_root)
1231 		set_sbi_flag(F2FS_SB(sb), SBI_IS_CLOSE);
1232 	kill_block_super(sb);
1233 }
1234 
1235 static struct file_system_type f2fs_fs_type = {
1236 	.owner		= THIS_MODULE,
1237 	.name		= "f2fs",
1238 	.mount		= f2fs_mount,
1239 	.kill_sb	= kill_f2fs_super,
1240 	.fs_flags	= FS_REQUIRES_DEV,
1241 };
1242 MODULE_ALIAS_FS("f2fs");
1243 
1244 static int __init init_inodecache(void)
1245 {
1246 	f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1247 			sizeof(struct f2fs_inode_info));
1248 	if (!f2fs_inode_cachep)
1249 		return -ENOMEM;
1250 	return 0;
1251 }
1252 
1253 static void destroy_inodecache(void)
1254 {
1255 	/*
1256 	 * Make sure all delayed rcu free inodes are flushed before we
1257 	 * destroy cache.
1258 	 */
1259 	rcu_barrier();
1260 	kmem_cache_destroy(f2fs_inode_cachep);
1261 }
1262 
1263 static int __init init_f2fs_fs(void)
1264 {
1265 	int err;
1266 
1267 	f2fs_build_trace_ios();
1268 
1269 	err = init_inodecache();
1270 	if (err)
1271 		goto fail;
1272 	err = create_node_manager_caches();
1273 	if (err)
1274 		goto free_inodecache;
1275 	err = create_segment_manager_caches();
1276 	if (err)
1277 		goto free_node_manager_caches;
1278 	err = create_checkpoint_caches();
1279 	if (err)
1280 		goto free_segment_manager_caches;
1281 	f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1282 	if (!f2fs_kset) {
1283 		err = -ENOMEM;
1284 		goto free_checkpoint_caches;
1285 	}
1286 	err = register_filesystem(&f2fs_fs_type);
1287 	if (err)
1288 		goto free_kset;
1289 	f2fs_create_root_stats();
1290 	f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1291 	return 0;
1292 
1293 free_kset:
1294 	kset_unregister(f2fs_kset);
1295 free_checkpoint_caches:
1296 	destroy_checkpoint_caches();
1297 free_segment_manager_caches:
1298 	destroy_segment_manager_caches();
1299 free_node_manager_caches:
1300 	destroy_node_manager_caches();
1301 free_inodecache:
1302 	destroy_inodecache();
1303 fail:
1304 	return err;
1305 }
1306 
1307 static void __exit exit_f2fs_fs(void)
1308 {
1309 	remove_proc_entry("fs/f2fs", NULL);
1310 	f2fs_destroy_root_stats();
1311 	unregister_filesystem(&f2fs_fs_type);
1312 	destroy_checkpoint_caches();
1313 	destroy_segment_manager_caches();
1314 	destroy_node_manager_caches();
1315 	destroy_inodecache();
1316 	kset_unregister(f2fs_kset);
1317 	f2fs_destroy_trace_ios();
1318 }
1319 
1320 module_init(init_f2fs_fs)
1321 module_exit(exit_f2fs_fs)
1322 
1323 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1324 MODULE_DESCRIPTION("Flash Friendly File System");
1325 MODULE_LICENSE("GPL");
1326