xref: /openbmc/linux/fs/f2fs/super.c (revision f35e839a)
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/random.h>
22 #include <linux/exportfs.h>
23 #include <linux/blkdev.h>
24 #include <linux/f2fs_fs.h>
25 
26 #include "f2fs.h"
27 #include "node.h"
28 #include "segment.h"
29 #include "xattr.h"
30 
31 #define CREATE_TRACE_POINTS
32 #include <trace/events/f2fs.h>
33 
34 static struct kmem_cache *f2fs_inode_cachep;
35 
36 enum {
37 	Opt_gc_background_off,
38 	Opt_disable_roll_forward,
39 	Opt_discard,
40 	Opt_noheap,
41 	Opt_nouser_xattr,
42 	Opt_noacl,
43 	Opt_active_logs,
44 	Opt_disable_ext_identify,
45 	Opt_err,
46 };
47 
48 static match_table_t f2fs_tokens = {
49 	{Opt_gc_background_off, "background_gc_off"},
50 	{Opt_disable_roll_forward, "disable_roll_forward"},
51 	{Opt_discard, "discard"},
52 	{Opt_noheap, "no_heap"},
53 	{Opt_nouser_xattr, "nouser_xattr"},
54 	{Opt_noacl, "noacl"},
55 	{Opt_active_logs, "active_logs=%u"},
56 	{Opt_disable_ext_identify, "disable_ext_identify"},
57 	{Opt_err, NULL},
58 };
59 
60 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
61 {
62 	struct va_format vaf;
63 	va_list args;
64 
65 	va_start(args, fmt);
66 	vaf.fmt = fmt;
67 	vaf.va = &args;
68 	printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
69 	va_end(args);
70 }
71 
72 static void init_once(void *foo)
73 {
74 	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
75 
76 	inode_init_once(&fi->vfs_inode);
77 }
78 
79 static struct inode *f2fs_alloc_inode(struct super_block *sb)
80 {
81 	struct f2fs_inode_info *fi;
82 
83 	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_NOFS | __GFP_ZERO);
84 	if (!fi)
85 		return NULL;
86 
87 	init_once((void *) fi);
88 
89 	/* Initialize f2fs-specific inode info */
90 	fi->vfs_inode.i_version = 1;
91 	atomic_set(&fi->dirty_dents, 0);
92 	fi->i_current_depth = 1;
93 	fi->i_advise = 0;
94 	rwlock_init(&fi->ext.ext_lock);
95 
96 	set_inode_flag(fi, FI_NEW_INODE);
97 
98 	return &fi->vfs_inode;
99 }
100 
101 static int f2fs_drop_inode(struct inode *inode)
102 {
103 	/*
104 	 * This is to avoid a deadlock condition like below.
105 	 * writeback_single_inode(inode)
106 	 *  - f2fs_write_data_page
107 	 *    - f2fs_gc -> iput -> evict
108 	 *       - inode_wait_for_writeback(inode)
109 	 */
110 	if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
111 		return 0;
112 	return generic_drop_inode(inode);
113 }
114 
115 static void f2fs_i_callback(struct rcu_head *head)
116 {
117 	struct inode *inode = container_of(head, struct inode, i_rcu);
118 	kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
119 }
120 
121 static void f2fs_destroy_inode(struct inode *inode)
122 {
123 	call_rcu(&inode->i_rcu, f2fs_i_callback);
124 }
125 
126 static void f2fs_put_super(struct super_block *sb)
127 {
128 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
129 
130 	f2fs_destroy_stats(sbi);
131 	stop_gc_thread(sbi);
132 
133 	write_checkpoint(sbi, true);
134 
135 	iput(sbi->node_inode);
136 	iput(sbi->meta_inode);
137 
138 	/* destroy f2fs internal modules */
139 	destroy_node_manager(sbi);
140 	destroy_segment_manager(sbi);
141 
142 	kfree(sbi->ckpt);
143 
144 	sb->s_fs_info = NULL;
145 	brelse(sbi->raw_super_buf);
146 	kfree(sbi);
147 }
148 
149 int f2fs_sync_fs(struct super_block *sb, int sync)
150 {
151 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
152 
153 	trace_f2fs_sync_fs(sb, sync);
154 
155 	if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
156 		return 0;
157 
158 	if (sync) {
159 		mutex_lock(&sbi->gc_mutex);
160 		write_checkpoint(sbi, false);
161 		mutex_unlock(&sbi->gc_mutex);
162 	} else {
163 		f2fs_balance_fs(sbi);
164 	}
165 
166 	return 0;
167 }
168 
169 static int f2fs_freeze(struct super_block *sb)
170 {
171 	int err;
172 
173 	if (sb->s_flags & MS_RDONLY)
174 		return 0;
175 
176 	err = f2fs_sync_fs(sb, 1);
177 	return err;
178 }
179 
180 static int f2fs_unfreeze(struct super_block *sb)
181 {
182 	return 0;
183 }
184 
185 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
186 {
187 	struct super_block *sb = dentry->d_sb;
188 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
189 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
190 	block_t total_count, user_block_count, start_count, ovp_count;
191 
192 	total_count = le64_to_cpu(sbi->raw_super->block_count);
193 	user_block_count = sbi->user_block_count;
194 	start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
195 	ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
196 	buf->f_type = F2FS_SUPER_MAGIC;
197 	buf->f_bsize = sbi->blocksize;
198 
199 	buf->f_blocks = total_count - start_count;
200 	buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
201 	buf->f_bavail = user_block_count - valid_user_blocks(sbi);
202 
203 	buf->f_files = sbi->total_node_count;
204 	buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
205 
206 	buf->f_namelen = F2FS_NAME_LEN;
207 	buf->f_fsid.val[0] = (u32)id;
208 	buf->f_fsid.val[1] = (u32)(id >> 32);
209 
210 	return 0;
211 }
212 
213 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
214 {
215 	struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
216 
217 	if (test_opt(sbi, BG_GC))
218 		seq_puts(seq, ",background_gc_on");
219 	else
220 		seq_puts(seq, ",background_gc_off");
221 	if (test_opt(sbi, DISABLE_ROLL_FORWARD))
222 		seq_puts(seq, ",disable_roll_forward");
223 	if (test_opt(sbi, DISCARD))
224 		seq_puts(seq, ",discard");
225 	if (test_opt(sbi, NOHEAP))
226 		seq_puts(seq, ",no_heap_alloc");
227 #ifdef CONFIG_F2FS_FS_XATTR
228 	if (test_opt(sbi, XATTR_USER))
229 		seq_puts(seq, ",user_xattr");
230 	else
231 		seq_puts(seq, ",nouser_xattr");
232 #endif
233 #ifdef CONFIG_F2FS_FS_POSIX_ACL
234 	if (test_opt(sbi, POSIX_ACL))
235 		seq_puts(seq, ",acl");
236 	else
237 		seq_puts(seq, ",noacl");
238 #endif
239 	if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
240 		seq_puts(seq, ",disable_ext_identify");
241 
242 	seq_printf(seq, ",active_logs=%u", sbi->active_logs);
243 
244 	return 0;
245 }
246 
247 static struct super_operations f2fs_sops = {
248 	.alloc_inode	= f2fs_alloc_inode,
249 	.drop_inode	= f2fs_drop_inode,
250 	.destroy_inode	= f2fs_destroy_inode,
251 	.write_inode	= f2fs_write_inode,
252 	.show_options	= f2fs_show_options,
253 	.evict_inode	= f2fs_evict_inode,
254 	.put_super	= f2fs_put_super,
255 	.sync_fs	= f2fs_sync_fs,
256 	.freeze_fs	= f2fs_freeze,
257 	.unfreeze_fs	= f2fs_unfreeze,
258 	.statfs		= f2fs_statfs,
259 };
260 
261 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
262 		u64 ino, u32 generation)
263 {
264 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
265 	struct inode *inode;
266 
267 	if (ino < F2FS_ROOT_INO(sbi))
268 		return ERR_PTR(-ESTALE);
269 
270 	/*
271 	 * f2fs_iget isn't quite right if the inode is currently unallocated!
272 	 * However f2fs_iget currently does appropriate checks to handle stale
273 	 * inodes so everything is OK.
274 	 */
275 	inode = f2fs_iget(sb, ino);
276 	if (IS_ERR(inode))
277 		return ERR_CAST(inode);
278 	if (generation && inode->i_generation != generation) {
279 		/* we didn't find the right inode.. */
280 		iput(inode);
281 		return ERR_PTR(-ESTALE);
282 	}
283 	return inode;
284 }
285 
286 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
287 		int fh_len, int fh_type)
288 {
289 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
290 				    f2fs_nfs_get_inode);
291 }
292 
293 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
294 		int fh_len, int fh_type)
295 {
296 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
297 				    f2fs_nfs_get_inode);
298 }
299 
300 static const struct export_operations f2fs_export_ops = {
301 	.fh_to_dentry = f2fs_fh_to_dentry,
302 	.fh_to_parent = f2fs_fh_to_parent,
303 	.get_parent = f2fs_get_parent,
304 };
305 
306 static int parse_options(struct super_block *sb, struct f2fs_sb_info *sbi,
307 				char *options)
308 {
309 	substring_t args[MAX_OPT_ARGS];
310 	char *p;
311 	int arg = 0;
312 
313 	if (!options)
314 		return 0;
315 
316 	while ((p = strsep(&options, ",")) != NULL) {
317 		int token;
318 		if (!*p)
319 			continue;
320 		/*
321 		 * Initialize args struct so we know whether arg was
322 		 * found; some options take optional arguments.
323 		 */
324 		args[0].to = args[0].from = NULL;
325 		token = match_token(p, f2fs_tokens, args);
326 
327 		switch (token) {
328 		case Opt_gc_background_off:
329 			clear_opt(sbi, BG_GC);
330 			break;
331 		case Opt_disable_roll_forward:
332 			set_opt(sbi, DISABLE_ROLL_FORWARD);
333 			break;
334 		case Opt_discard:
335 			set_opt(sbi, DISCARD);
336 			break;
337 		case Opt_noheap:
338 			set_opt(sbi, NOHEAP);
339 			break;
340 #ifdef CONFIG_F2FS_FS_XATTR
341 		case Opt_nouser_xattr:
342 			clear_opt(sbi, XATTR_USER);
343 			break;
344 #else
345 		case Opt_nouser_xattr:
346 			f2fs_msg(sb, KERN_INFO,
347 				"nouser_xattr options not supported");
348 			break;
349 #endif
350 #ifdef CONFIG_F2FS_FS_POSIX_ACL
351 		case Opt_noacl:
352 			clear_opt(sbi, POSIX_ACL);
353 			break;
354 #else
355 		case Opt_noacl:
356 			f2fs_msg(sb, KERN_INFO, "noacl options not supported");
357 			break;
358 #endif
359 		case Opt_active_logs:
360 			if (args->from && match_int(args, &arg))
361 				return -EINVAL;
362 			if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
363 				return -EINVAL;
364 			sbi->active_logs = arg;
365 			break;
366 		case Opt_disable_ext_identify:
367 			set_opt(sbi, DISABLE_EXT_IDENTIFY);
368 			break;
369 		default:
370 			f2fs_msg(sb, KERN_ERR,
371 				"Unrecognized mount option \"%s\" or missing value",
372 				p);
373 			return -EINVAL;
374 		}
375 	}
376 	return 0;
377 }
378 
379 static loff_t max_file_size(unsigned bits)
380 {
381 	loff_t result = ADDRS_PER_INODE;
382 	loff_t leaf_count = ADDRS_PER_BLOCK;
383 
384 	/* two direct node blocks */
385 	result += (leaf_count * 2);
386 
387 	/* two indirect node blocks */
388 	leaf_count *= NIDS_PER_BLOCK;
389 	result += (leaf_count * 2);
390 
391 	/* one double indirect node block */
392 	leaf_count *= NIDS_PER_BLOCK;
393 	result += leaf_count;
394 
395 	result <<= bits;
396 	return result;
397 }
398 
399 static int sanity_check_raw_super(struct super_block *sb,
400 			struct f2fs_super_block *raw_super)
401 {
402 	unsigned int blocksize;
403 
404 	if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
405 		f2fs_msg(sb, KERN_INFO,
406 			"Magic Mismatch, valid(0x%x) - read(0x%x)",
407 			F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
408 		return 1;
409 	}
410 
411 	/* Currently, support only 4KB page cache size */
412 	if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
413 		f2fs_msg(sb, KERN_INFO,
414 			"Invalid page_cache_size (%lu), supports only 4KB\n",
415 			PAGE_CACHE_SIZE);
416 		return 1;
417 	}
418 
419 	/* Currently, support only 4KB block size */
420 	blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
421 	if (blocksize != F2FS_BLKSIZE) {
422 		f2fs_msg(sb, KERN_INFO,
423 			"Invalid blocksize (%u), supports only 4KB\n",
424 			blocksize);
425 		return 1;
426 	}
427 
428 	if (le32_to_cpu(raw_super->log_sectorsize) !=
429 					F2FS_LOG_SECTOR_SIZE) {
430 		f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
431 		return 1;
432 	}
433 	if (le32_to_cpu(raw_super->log_sectors_per_block) !=
434 					F2FS_LOG_SECTORS_PER_BLOCK) {
435 		f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
436 		return 1;
437 	}
438 	return 0;
439 }
440 
441 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
442 {
443 	unsigned int total, fsmeta;
444 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
445 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
446 
447 	total = le32_to_cpu(raw_super->segment_count);
448 	fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
449 	fsmeta += le32_to_cpu(raw_super->segment_count_sit);
450 	fsmeta += le32_to_cpu(raw_super->segment_count_nat);
451 	fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
452 	fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
453 
454 	if (fsmeta >= total)
455 		return 1;
456 
457 	if (is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) {
458 		f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
459 		return 1;
460 	}
461 	return 0;
462 }
463 
464 static void init_sb_info(struct f2fs_sb_info *sbi)
465 {
466 	struct f2fs_super_block *raw_super = sbi->raw_super;
467 	int i;
468 
469 	sbi->log_sectors_per_block =
470 		le32_to_cpu(raw_super->log_sectors_per_block);
471 	sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
472 	sbi->blocksize = 1 << sbi->log_blocksize;
473 	sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
474 	sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
475 	sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
476 	sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
477 	sbi->total_sections = le32_to_cpu(raw_super->section_count);
478 	sbi->total_node_count =
479 		(le32_to_cpu(raw_super->segment_count_nat) / 2)
480 			* sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
481 	sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
482 	sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
483 	sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
484 	sbi->cur_victim_sec = NULL_SECNO;
485 
486 	for (i = 0; i < NR_COUNT_TYPE; i++)
487 		atomic_set(&sbi->nr_pages[i], 0);
488 }
489 
490 static int validate_superblock(struct super_block *sb,
491 		struct f2fs_super_block **raw_super,
492 		struct buffer_head **raw_super_buf, sector_t block)
493 {
494 	const char *super = (block == 0 ? "first" : "second");
495 
496 	/* read f2fs raw super block */
497 	*raw_super_buf = sb_bread(sb, block);
498 	if (!*raw_super_buf) {
499 		f2fs_msg(sb, KERN_ERR, "unable to read %s superblock",
500 				super);
501 		return -EIO;
502 	}
503 
504 	*raw_super = (struct f2fs_super_block *)
505 		((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
506 
507 	/* sanity checking of raw super */
508 	if (!sanity_check_raw_super(sb, *raw_super))
509 		return 0;
510 
511 	f2fs_msg(sb, KERN_ERR, "Can't find a valid F2FS filesystem "
512 				"in %s superblock", super);
513 	return -EINVAL;
514 }
515 
516 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
517 {
518 	struct f2fs_sb_info *sbi;
519 	struct f2fs_super_block *raw_super;
520 	struct buffer_head *raw_super_buf;
521 	struct inode *root;
522 	long err = -EINVAL;
523 	int i;
524 
525 	/* allocate memory for f2fs-specific super block info */
526 	sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
527 	if (!sbi)
528 		return -ENOMEM;
529 
530 	/* set a block size */
531 	if (!sb_set_blocksize(sb, F2FS_BLKSIZE)) {
532 		f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
533 		goto free_sbi;
534 	}
535 
536 	err = validate_superblock(sb, &raw_super, &raw_super_buf, 0);
537 	if (err) {
538 		brelse(raw_super_buf);
539 		/* check secondary superblock when primary failed */
540 		err = validate_superblock(sb, &raw_super, &raw_super_buf, 1);
541 		if (err)
542 			goto free_sb_buf;
543 	}
544 	/* init some FS parameters */
545 	sbi->active_logs = NR_CURSEG_TYPE;
546 
547 	set_opt(sbi, BG_GC);
548 
549 #ifdef CONFIG_F2FS_FS_XATTR
550 	set_opt(sbi, XATTR_USER);
551 #endif
552 #ifdef CONFIG_F2FS_FS_POSIX_ACL
553 	set_opt(sbi, POSIX_ACL);
554 #endif
555 	/* parse mount options */
556 	err = parse_options(sb, sbi, (char *)data);
557 	if (err)
558 		goto free_sb_buf;
559 
560 	sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
561 	sb->s_max_links = F2FS_LINK_MAX;
562 	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
563 
564 	sb->s_op = &f2fs_sops;
565 	sb->s_xattr = f2fs_xattr_handlers;
566 	sb->s_export_op = &f2fs_export_ops;
567 	sb->s_magic = F2FS_SUPER_MAGIC;
568 	sb->s_fs_info = sbi;
569 	sb->s_time_gran = 1;
570 	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
571 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
572 	memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
573 
574 	/* init f2fs-specific super block info */
575 	sbi->sb = sb;
576 	sbi->raw_super = raw_super;
577 	sbi->raw_super_buf = raw_super_buf;
578 	mutex_init(&sbi->gc_mutex);
579 	mutex_init(&sbi->writepages);
580 	mutex_init(&sbi->cp_mutex);
581 	for (i = 0; i < NR_GLOBAL_LOCKS; i++)
582 		mutex_init(&sbi->fs_lock[i]);
583 	mutex_init(&sbi->node_write);
584 	sbi->por_doing = 0;
585 	spin_lock_init(&sbi->stat_lock);
586 	init_rwsem(&sbi->bio_sem);
587 	init_sb_info(sbi);
588 
589 	/* get an inode for meta space */
590 	sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
591 	if (IS_ERR(sbi->meta_inode)) {
592 		f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
593 		err = PTR_ERR(sbi->meta_inode);
594 		goto free_sb_buf;
595 	}
596 
597 	err = get_valid_checkpoint(sbi);
598 	if (err) {
599 		f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
600 		goto free_meta_inode;
601 	}
602 
603 	/* sanity checking of checkpoint */
604 	err = -EINVAL;
605 	if (sanity_check_ckpt(sbi)) {
606 		f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
607 		goto free_cp;
608 	}
609 
610 	sbi->total_valid_node_count =
611 				le32_to_cpu(sbi->ckpt->valid_node_count);
612 	sbi->total_valid_inode_count =
613 				le32_to_cpu(sbi->ckpt->valid_inode_count);
614 	sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
615 	sbi->total_valid_block_count =
616 				le64_to_cpu(sbi->ckpt->valid_block_count);
617 	sbi->last_valid_block_count = sbi->total_valid_block_count;
618 	sbi->alloc_valid_block_count = 0;
619 	INIT_LIST_HEAD(&sbi->dir_inode_list);
620 	spin_lock_init(&sbi->dir_inode_lock);
621 
622 	init_orphan_info(sbi);
623 
624 	/* setup f2fs internal modules */
625 	err = build_segment_manager(sbi);
626 	if (err) {
627 		f2fs_msg(sb, KERN_ERR,
628 			"Failed to initialize F2FS segment manager");
629 		goto free_sm;
630 	}
631 	err = build_node_manager(sbi);
632 	if (err) {
633 		f2fs_msg(sb, KERN_ERR,
634 			"Failed to initialize F2FS node manager");
635 		goto free_nm;
636 	}
637 
638 	build_gc_manager(sbi);
639 
640 	/* get an inode for node space */
641 	sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
642 	if (IS_ERR(sbi->node_inode)) {
643 		f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
644 		err = PTR_ERR(sbi->node_inode);
645 		goto free_nm;
646 	}
647 
648 	/* if there are nt orphan nodes free them */
649 	err = -EINVAL;
650 	if (recover_orphan_inodes(sbi))
651 		goto free_node_inode;
652 
653 	/* read root inode and dentry */
654 	root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
655 	if (IS_ERR(root)) {
656 		f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
657 		err = PTR_ERR(root);
658 		goto free_node_inode;
659 	}
660 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size)
661 		goto free_root_inode;
662 
663 	sb->s_root = d_make_root(root); /* allocate root dentry */
664 	if (!sb->s_root) {
665 		err = -ENOMEM;
666 		goto free_root_inode;
667 	}
668 
669 	/* recover fsynced data */
670 	if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
671 		err = recover_fsync_data(sbi);
672 		if (err)
673 			f2fs_msg(sb, KERN_ERR,
674 				"Cannot recover all fsync data errno=%ld", err);
675 	}
676 
677 	/* After POR, we can run background GC thread */
678 	err = start_gc_thread(sbi);
679 	if (err)
680 		goto fail;
681 
682 	err = f2fs_build_stats(sbi);
683 	if (err)
684 		goto fail;
685 
686 	if (test_opt(sbi, DISCARD)) {
687 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
688 		if (!blk_queue_discard(q))
689 			f2fs_msg(sb, KERN_WARNING,
690 					"mounting with \"discard\" option, but "
691 					"the device does not support discard");
692 	}
693 
694 	return 0;
695 fail:
696 	stop_gc_thread(sbi);
697 free_root_inode:
698 	dput(sb->s_root);
699 	sb->s_root = NULL;
700 free_node_inode:
701 	iput(sbi->node_inode);
702 free_nm:
703 	destroy_node_manager(sbi);
704 free_sm:
705 	destroy_segment_manager(sbi);
706 free_cp:
707 	kfree(sbi->ckpt);
708 free_meta_inode:
709 	make_bad_inode(sbi->meta_inode);
710 	iput(sbi->meta_inode);
711 free_sb_buf:
712 	brelse(raw_super_buf);
713 free_sbi:
714 	kfree(sbi);
715 	return err;
716 }
717 
718 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
719 			const char *dev_name, void *data)
720 {
721 	return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
722 }
723 
724 static struct file_system_type f2fs_fs_type = {
725 	.owner		= THIS_MODULE,
726 	.name		= "f2fs",
727 	.mount		= f2fs_mount,
728 	.kill_sb	= kill_block_super,
729 	.fs_flags	= FS_REQUIRES_DEV,
730 };
731 MODULE_ALIAS_FS("f2fs");
732 
733 static int __init init_inodecache(void)
734 {
735 	f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
736 			sizeof(struct f2fs_inode_info), NULL);
737 	if (f2fs_inode_cachep == NULL)
738 		return -ENOMEM;
739 	return 0;
740 }
741 
742 static void destroy_inodecache(void)
743 {
744 	/*
745 	 * Make sure all delayed rcu free inodes are flushed before we
746 	 * destroy cache.
747 	 */
748 	rcu_barrier();
749 	kmem_cache_destroy(f2fs_inode_cachep);
750 }
751 
752 static int __init init_f2fs_fs(void)
753 {
754 	int err;
755 
756 	err = init_inodecache();
757 	if (err)
758 		goto fail;
759 	err = create_node_manager_caches();
760 	if (err)
761 		goto fail;
762 	err = create_gc_caches();
763 	if (err)
764 		goto fail;
765 	err = create_checkpoint_caches();
766 	if (err)
767 		goto fail;
768 	err = register_filesystem(&f2fs_fs_type);
769 	if (err)
770 		goto fail;
771 	f2fs_create_root_stats();
772 fail:
773 	return err;
774 }
775 
776 static void __exit exit_f2fs_fs(void)
777 {
778 	f2fs_destroy_root_stats();
779 	unregister_filesystem(&f2fs_fs_type);
780 	destroy_checkpoint_caches();
781 	destroy_gc_caches();
782 	destroy_node_manager_caches();
783 	destroy_inodecache();
784 }
785 
786 module_init(init_f2fs_fs)
787 module_exit(exit_f2fs_fs)
788 
789 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
790 MODULE_DESCRIPTION("Flash Friendly File System");
791 MODULE_LICENSE("GPL");
792