xref: /openbmc/linux/fs/f2fs/super.c (revision b3980910f746d885111db7252f664600de2a5ea3)
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 /* f2fs-wide shrinker description */
43 static struct shrinker f2fs_shrinker_info = {
44 	.scan_objects = f2fs_shrink_scan,
45 	.count_objects = f2fs_shrink_count,
46 	.seeks = DEFAULT_SEEKS,
47 };
48 
49 enum {
50 	Opt_gc_background,
51 	Opt_disable_roll_forward,
52 	Opt_norecovery,
53 	Opt_discard,
54 	Opt_noheap,
55 	Opt_user_xattr,
56 	Opt_nouser_xattr,
57 	Opt_acl,
58 	Opt_noacl,
59 	Opt_active_logs,
60 	Opt_disable_ext_identify,
61 	Opt_inline_xattr,
62 	Opt_inline_data,
63 	Opt_inline_dentry,
64 	Opt_flush_merge,
65 	Opt_nobarrier,
66 	Opt_fastboot,
67 	Opt_extent_cache,
68 	Opt_noextent_cache,
69 	Opt_noinline_data,
70 	Opt_err,
71 };
72 
73 static match_table_t f2fs_tokens = {
74 	{Opt_gc_background, "background_gc=%s"},
75 	{Opt_disable_roll_forward, "disable_roll_forward"},
76 	{Opt_norecovery, "norecovery"},
77 	{Opt_discard, "discard"},
78 	{Opt_noheap, "no_heap"},
79 	{Opt_user_xattr, "user_xattr"},
80 	{Opt_nouser_xattr, "nouser_xattr"},
81 	{Opt_acl, "acl"},
82 	{Opt_noacl, "noacl"},
83 	{Opt_active_logs, "active_logs=%u"},
84 	{Opt_disable_ext_identify, "disable_ext_identify"},
85 	{Opt_inline_xattr, "inline_xattr"},
86 	{Opt_inline_data, "inline_data"},
87 	{Opt_inline_dentry, "inline_dentry"},
88 	{Opt_flush_merge, "flush_merge"},
89 	{Opt_nobarrier, "nobarrier"},
90 	{Opt_fastboot, "fastboot"},
91 	{Opt_extent_cache, "extent_cache"},
92 	{Opt_noextent_cache, "noextent_cache"},
93 	{Opt_noinline_data, "noinline_data"},
94 	{Opt_err, NULL},
95 };
96 
97 /* Sysfs support for f2fs */
98 enum {
99 	GC_THREAD,	/* struct f2fs_gc_thread */
100 	SM_INFO,	/* struct f2fs_sm_info */
101 	NM_INFO,	/* struct f2fs_nm_info */
102 	F2FS_SBI,	/* struct f2fs_sb_info */
103 };
104 
105 struct f2fs_attr {
106 	struct attribute attr;
107 	ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
108 	ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
109 			 const char *, size_t);
110 	int struct_type;
111 	int offset;
112 };
113 
114 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
115 {
116 	if (struct_type == GC_THREAD)
117 		return (unsigned char *)sbi->gc_thread;
118 	else if (struct_type == SM_INFO)
119 		return (unsigned char *)SM_I(sbi);
120 	else if (struct_type == NM_INFO)
121 		return (unsigned char *)NM_I(sbi);
122 	else if (struct_type == F2FS_SBI)
123 		return (unsigned char *)sbi;
124 	return NULL;
125 }
126 
127 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
128 			struct f2fs_sb_info *sbi, char *buf)
129 {
130 	unsigned char *ptr = NULL;
131 	unsigned int *ui;
132 
133 	ptr = __struct_ptr(sbi, a->struct_type);
134 	if (!ptr)
135 		return -EINVAL;
136 
137 	ui = (unsigned int *)(ptr + a->offset);
138 
139 	return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
140 }
141 
142 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
143 			struct f2fs_sb_info *sbi,
144 			const char *buf, size_t count)
145 {
146 	unsigned char *ptr;
147 	unsigned long t;
148 	unsigned int *ui;
149 	ssize_t ret;
150 
151 	ptr = __struct_ptr(sbi, a->struct_type);
152 	if (!ptr)
153 		return -EINVAL;
154 
155 	ui = (unsigned int *)(ptr + a->offset);
156 
157 	ret = kstrtoul(skip_spaces(buf), 0, &t);
158 	if (ret < 0)
159 		return ret;
160 	*ui = t;
161 	return count;
162 }
163 
164 static ssize_t f2fs_attr_show(struct kobject *kobj,
165 				struct attribute *attr, char *buf)
166 {
167 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
168 								s_kobj);
169 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
170 
171 	return a->show ? a->show(a, sbi, buf) : 0;
172 }
173 
174 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
175 						const char *buf, size_t len)
176 {
177 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
178 									s_kobj);
179 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
180 
181 	return a->store ? a->store(a, sbi, buf, len) : 0;
182 }
183 
184 static void f2fs_sb_release(struct kobject *kobj)
185 {
186 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
187 								s_kobj);
188 	complete(&sbi->s_kobj_unregister);
189 }
190 
191 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
192 static struct f2fs_attr f2fs_attr_##_name = {			\
193 	.attr = {.name = __stringify(_name), .mode = _mode },	\
194 	.show	= _show,					\
195 	.store	= _store,					\
196 	.struct_type = _struct_type,				\
197 	.offset = _offset					\
198 }
199 
200 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)	\
201 	F2FS_ATTR_OFFSET(struct_type, name, 0644,		\
202 		f2fs_sbi_show, f2fs_sbi_store,			\
203 		offsetof(struct struct_name, elname))
204 
205 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
206 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
207 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
208 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
209 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
210 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
211 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, batched_trim_sections, trim_sections);
212 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
213 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
214 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks);
215 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
216 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ra_nid_pages, ra_nid_pages);
217 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
218 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
219 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, cp_interval, cp_interval);
220 
221 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
222 static struct attribute *f2fs_attrs[] = {
223 	ATTR_LIST(gc_min_sleep_time),
224 	ATTR_LIST(gc_max_sleep_time),
225 	ATTR_LIST(gc_no_gc_sleep_time),
226 	ATTR_LIST(gc_idle),
227 	ATTR_LIST(reclaim_segments),
228 	ATTR_LIST(max_small_discards),
229 	ATTR_LIST(batched_trim_sections),
230 	ATTR_LIST(ipu_policy),
231 	ATTR_LIST(min_ipu_util),
232 	ATTR_LIST(min_fsync_blocks),
233 	ATTR_LIST(max_victim_search),
234 	ATTR_LIST(dir_level),
235 	ATTR_LIST(ram_thresh),
236 	ATTR_LIST(ra_nid_pages),
237 	ATTR_LIST(cp_interval),
238 	NULL,
239 };
240 
241 static const struct sysfs_ops f2fs_attr_ops = {
242 	.show	= f2fs_attr_show,
243 	.store	= f2fs_attr_store,
244 };
245 
246 static struct kobj_type f2fs_ktype = {
247 	.default_attrs	= f2fs_attrs,
248 	.sysfs_ops	= &f2fs_attr_ops,
249 	.release	= f2fs_sb_release,
250 };
251 
252 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
253 {
254 	struct va_format vaf;
255 	va_list args;
256 
257 	va_start(args, fmt);
258 	vaf.fmt = fmt;
259 	vaf.va = &args;
260 	printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
261 	va_end(args);
262 }
263 
264 static void init_once(void *foo)
265 {
266 	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
267 
268 	inode_init_once(&fi->vfs_inode);
269 }
270 
271 static int parse_options(struct super_block *sb, char *options)
272 {
273 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
274 	struct request_queue *q;
275 	substring_t args[MAX_OPT_ARGS];
276 	char *p, *name;
277 	int arg = 0;
278 
279 	if (!options)
280 		return 0;
281 
282 	while ((p = strsep(&options, ",")) != NULL) {
283 		int token;
284 		if (!*p)
285 			continue;
286 		/*
287 		 * Initialize args struct so we know whether arg was
288 		 * found; some options take optional arguments.
289 		 */
290 		args[0].to = args[0].from = NULL;
291 		token = match_token(p, f2fs_tokens, args);
292 
293 		switch (token) {
294 		case Opt_gc_background:
295 			name = match_strdup(&args[0]);
296 
297 			if (!name)
298 				return -ENOMEM;
299 			if (strlen(name) == 2 && !strncmp(name, "on", 2)) {
300 				set_opt(sbi, BG_GC);
301 				clear_opt(sbi, FORCE_FG_GC);
302 			} else if (strlen(name) == 3 && !strncmp(name, "off", 3)) {
303 				clear_opt(sbi, BG_GC);
304 				clear_opt(sbi, FORCE_FG_GC);
305 			} else if (strlen(name) == 4 && !strncmp(name, "sync", 4)) {
306 				set_opt(sbi, BG_GC);
307 				set_opt(sbi, FORCE_FG_GC);
308 			} else {
309 				kfree(name);
310 				return -EINVAL;
311 			}
312 			kfree(name);
313 			break;
314 		case Opt_disable_roll_forward:
315 			set_opt(sbi, DISABLE_ROLL_FORWARD);
316 			break;
317 		case Opt_norecovery:
318 			/* this option mounts f2fs with ro */
319 			set_opt(sbi, DISABLE_ROLL_FORWARD);
320 			if (!f2fs_readonly(sb))
321 				return -EINVAL;
322 			break;
323 		case Opt_discard:
324 			q = bdev_get_queue(sb->s_bdev);
325 			if (blk_queue_discard(q)) {
326 				set_opt(sbi, DISCARD);
327 			} else {
328 				f2fs_msg(sb, KERN_WARNING,
329 					"mounting with \"discard\" option, but "
330 					"the device does not support discard");
331 			}
332 			break;
333 		case Opt_noheap:
334 			set_opt(sbi, NOHEAP);
335 			break;
336 #ifdef CONFIG_F2FS_FS_XATTR
337 		case Opt_user_xattr:
338 			set_opt(sbi, XATTR_USER);
339 			break;
340 		case Opt_nouser_xattr:
341 			clear_opt(sbi, XATTR_USER);
342 			break;
343 		case Opt_inline_xattr:
344 			set_opt(sbi, INLINE_XATTR);
345 			break;
346 #else
347 		case Opt_user_xattr:
348 			f2fs_msg(sb, KERN_INFO,
349 				"user_xattr options not supported");
350 			break;
351 		case Opt_nouser_xattr:
352 			f2fs_msg(sb, KERN_INFO,
353 				"nouser_xattr options not supported");
354 			break;
355 		case Opt_inline_xattr:
356 			f2fs_msg(sb, KERN_INFO,
357 				"inline_xattr options not supported");
358 			break;
359 #endif
360 #ifdef CONFIG_F2FS_FS_POSIX_ACL
361 		case Opt_acl:
362 			set_opt(sbi, POSIX_ACL);
363 			break;
364 		case Opt_noacl:
365 			clear_opt(sbi, POSIX_ACL);
366 			break;
367 #else
368 		case Opt_acl:
369 			f2fs_msg(sb, KERN_INFO, "acl options not supported");
370 			break;
371 		case Opt_noacl:
372 			f2fs_msg(sb, KERN_INFO, "noacl options not supported");
373 			break;
374 #endif
375 		case Opt_active_logs:
376 			if (args->from && match_int(args, &arg))
377 				return -EINVAL;
378 			if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
379 				return -EINVAL;
380 			sbi->active_logs = arg;
381 			break;
382 		case Opt_disable_ext_identify:
383 			set_opt(sbi, DISABLE_EXT_IDENTIFY);
384 			break;
385 		case Opt_inline_data:
386 			set_opt(sbi, INLINE_DATA);
387 			break;
388 		case Opt_inline_dentry:
389 			set_opt(sbi, INLINE_DENTRY);
390 			break;
391 		case Opt_flush_merge:
392 			set_opt(sbi, FLUSH_MERGE);
393 			break;
394 		case Opt_nobarrier:
395 			set_opt(sbi, NOBARRIER);
396 			break;
397 		case Opt_fastboot:
398 			set_opt(sbi, FASTBOOT);
399 			break;
400 		case Opt_extent_cache:
401 			set_opt(sbi, EXTENT_CACHE);
402 			break;
403 		case Opt_noextent_cache:
404 			clear_opt(sbi, EXTENT_CACHE);
405 			break;
406 		case Opt_noinline_data:
407 			clear_opt(sbi, INLINE_DATA);
408 			break;
409 		default:
410 			f2fs_msg(sb, KERN_ERR,
411 				"Unrecognized mount option \"%s\" or missing value",
412 				p);
413 			return -EINVAL;
414 		}
415 	}
416 	return 0;
417 }
418 
419 static struct inode *f2fs_alloc_inode(struct super_block *sb)
420 {
421 	struct f2fs_inode_info *fi;
422 
423 	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
424 	if (!fi)
425 		return NULL;
426 
427 	init_once((void *) fi);
428 
429 	/* Initialize f2fs-specific inode info */
430 	fi->vfs_inode.i_version = 1;
431 	atomic_set(&fi->dirty_pages, 0);
432 	fi->i_current_depth = 1;
433 	fi->i_advise = 0;
434 	init_rwsem(&fi->i_sem);
435 	INIT_LIST_HEAD(&fi->dirty_list);
436 	INIT_LIST_HEAD(&fi->inmem_pages);
437 	mutex_init(&fi->inmem_lock);
438 
439 	set_inode_flag(fi, FI_NEW_INODE);
440 
441 	if (test_opt(F2FS_SB(sb), INLINE_XATTR))
442 		set_inode_flag(fi, FI_INLINE_XATTR);
443 
444 	/* Will be used by directory only */
445 	fi->i_dir_level = F2FS_SB(sb)->dir_level;
446 
447 #ifdef CONFIG_F2FS_FS_ENCRYPTION
448 	fi->i_crypt_info = NULL;
449 #endif
450 	return &fi->vfs_inode;
451 }
452 
453 static int f2fs_drop_inode(struct inode *inode)
454 {
455 	/*
456 	 * This is to avoid a deadlock condition like below.
457 	 * writeback_single_inode(inode)
458 	 *  - f2fs_write_data_page
459 	 *    - f2fs_gc -> iput -> evict
460 	 *       - inode_wait_for_writeback(inode)
461 	 */
462 	if (!inode_unhashed(inode) && inode->i_state & I_SYNC) {
463 		if (!inode->i_nlink && !is_bad_inode(inode)) {
464 			/* to avoid evict_inode call simultaneously */
465 			atomic_inc(&inode->i_count);
466 			spin_unlock(&inode->i_lock);
467 
468 			/* some remained atomic pages should discarded */
469 			if (f2fs_is_atomic_file(inode))
470 				commit_inmem_pages(inode, true);
471 
472 			/* should remain fi->extent_tree for writepage */
473 			f2fs_destroy_extent_node(inode);
474 
475 			sb_start_intwrite(inode->i_sb);
476 			i_size_write(inode, 0);
477 
478 			if (F2FS_HAS_BLOCKS(inode))
479 				f2fs_truncate(inode, true);
480 
481 			sb_end_intwrite(inode->i_sb);
482 
483 #ifdef CONFIG_F2FS_FS_ENCRYPTION
484 			if (F2FS_I(inode)->i_crypt_info)
485 				f2fs_free_encryption_info(inode,
486 					F2FS_I(inode)->i_crypt_info);
487 #endif
488 			spin_lock(&inode->i_lock);
489 			atomic_dec(&inode->i_count);
490 		}
491 		return 0;
492 	}
493 	return generic_drop_inode(inode);
494 }
495 
496 /*
497  * f2fs_dirty_inode() is called from __mark_inode_dirty()
498  *
499  * We should call set_dirty_inode to write the dirty inode through write_inode.
500  */
501 static void f2fs_dirty_inode(struct inode *inode, int flags)
502 {
503 	set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
504 }
505 
506 static void f2fs_i_callback(struct rcu_head *head)
507 {
508 	struct inode *inode = container_of(head, struct inode, i_rcu);
509 	kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
510 }
511 
512 static void f2fs_destroy_inode(struct inode *inode)
513 {
514 	call_rcu(&inode->i_rcu, f2fs_i_callback);
515 }
516 
517 static void f2fs_put_super(struct super_block *sb)
518 {
519 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
520 
521 	if (sbi->s_proc) {
522 		remove_proc_entry("segment_info", sbi->s_proc);
523 		remove_proc_entry(sb->s_id, f2fs_proc_root);
524 	}
525 	kobject_del(&sbi->s_kobj);
526 
527 	stop_gc_thread(sbi);
528 
529 	/* prevent remaining shrinker jobs */
530 	mutex_lock(&sbi->umount_mutex);
531 
532 	/*
533 	 * We don't need to do checkpoint when superblock is clean.
534 	 * But, the previous checkpoint was not done by umount, it needs to do
535 	 * clean checkpoint again.
536 	 */
537 	if (is_sbi_flag_set(sbi, SBI_IS_DIRTY) ||
538 			!is_set_ckpt_flags(F2FS_CKPT(sbi), CP_UMOUNT_FLAG)) {
539 		struct cp_control cpc = {
540 			.reason = CP_UMOUNT,
541 		};
542 		write_checkpoint(sbi, &cpc);
543 	}
544 
545 	/* write_checkpoint can update stat informaion */
546 	f2fs_destroy_stats(sbi);
547 
548 	/*
549 	 * normally superblock is clean, so we need to release this.
550 	 * In addition, EIO will skip do checkpoint, we need this as well.
551 	 */
552 	release_ino_entry(sbi);
553 	release_discard_addrs(sbi);
554 
555 	f2fs_leave_shrinker(sbi);
556 	mutex_unlock(&sbi->umount_mutex);
557 
558 	iput(sbi->node_inode);
559 	iput(sbi->meta_inode);
560 
561 	/* destroy f2fs internal modules */
562 	destroy_node_manager(sbi);
563 	destroy_segment_manager(sbi);
564 
565 	kfree(sbi->ckpt);
566 	kobject_put(&sbi->s_kobj);
567 	wait_for_completion(&sbi->s_kobj_unregister);
568 
569 	sb->s_fs_info = NULL;
570 	kfree(sbi->raw_super);
571 	kfree(sbi);
572 }
573 
574 int f2fs_sync_fs(struct super_block *sb, int sync)
575 {
576 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
577 
578 	trace_f2fs_sync_fs(sb, sync);
579 
580 	if (sync) {
581 		struct cp_control cpc;
582 
583 		cpc.reason = __get_cp_reason(sbi);
584 
585 		mutex_lock(&sbi->gc_mutex);
586 		write_checkpoint(sbi, &cpc);
587 		mutex_unlock(&sbi->gc_mutex);
588 	} else {
589 		f2fs_balance_fs(sbi);
590 	}
591 	f2fs_trace_ios(NULL, 1);
592 
593 	return 0;
594 }
595 
596 static int f2fs_freeze(struct super_block *sb)
597 {
598 	int err;
599 
600 	if (f2fs_readonly(sb))
601 		return 0;
602 
603 	err = f2fs_sync_fs(sb, 1);
604 	return err;
605 }
606 
607 static int f2fs_unfreeze(struct super_block *sb)
608 {
609 	return 0;
610 }
611 
612 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
613 {
614 	struct super_block *sb = dentry->d_sb;
615 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
616 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
617 	block_t total_count, user_block_count, start_count, ovp_count;
618 
619 	total_count = le64_to_cpu(sbi->raw_super->block_count);
620 	user_block_count = sbi->user_block_count;
621 	start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
622 	ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
623 	buf->f_type = F2FS_SUPER_MAGIC;
624 	buf->f_bsize = sbi->blocksize;
625 
626 	buf->f_blocks = total_count - start_count;
627 	buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
628 	buf->f_bavail = user_block_count - valid_user_blocks(sbi);
629 
630 	buf->f_files = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
631 	buf->f_ffree = buf->f_files - valid_inode_count(sbi);
632 
633 	buf->f_namelen = F2FS_NAME_LEN;
634 	buf->f_fsid.val[0] = (u32)id;
635 	buf->f_fsid.val[1] = (u32)(id >> 32);
636 
637 	return 0;
638 }
639 
640 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
641 {
642 	struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
643 
644 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC)) {
645 		if (test_opt(sbi, FORCE_FG_GC))
646 			seq_printf(seq, ",background_gc=%s", "sync");
647 		else
648 			seq_printf(seq, ",background_gc=%s", "on");
649 	} else {
650 		seq_printf(seq, ",background_gc=%s", "off");
651 	}
652 	if (test_opt(sbi, DISABLE_ROLL_FORWARD))
653 		seq_puts(seq, ",disable_roll_forward");
654 	if (test_opt(sbi, DISCARD))
655 		seq_puts(seq, ",discard");
656 	if (test_opt(sbi, NOHEAP))
657 		seq_puts(seq, ",no_heap_alloc");
658 #ifdef CONFIG_F2FS_FS_XATTR
659 	if (test_opt(sbi, XATTR_USER))
660 		seq_puts(seq, ",user_xattr");
661 	else
662 		seq_puts(seq, ",nouser_xattr");
663 	if (test_opt(sbi, INLINE_XATTR))
664 		seq_puts(seq, ",inline_xattr");
665 #endif
666 #ifdef CONFIG_F2FS_FS_POSIX_ACL
667 	if (test_opt(sbi, POSIX_ACL))
668 		seq_puts(seq, ",acl");
669 	else
670 		seq_puts(seq, ",noacl");
671 #endif
672 	if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
673 		seq_puts(seq, ",disable_ext_identify");
674 	if (test_opt(sbi, INLINE_DATA))
675 		seq_puts(seq, ",inline_data");
676 	else
677 		seq_puts(seq, ",noinline_data");
678 	if (test_opt(sbi, INLINE_DENTRY))
679 		seq_puts(seq, ",inline_dentry");
680 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
681 		seq_puts(seq, ",flush_merge");
682 	if (test_opt(sbi, NOBARRIER))
683 		seq_puts(seq, ",nobarrier");
684 	if (test_opt(sbi, FASTBOOT))
685 		seq_puts(seq, ",fastboot");
686 	if (test_opt(sbi, EXTENT_CACHE))
687 		seq_puts(seq, ",extent_cache");
688 	else
689 		seq_puts(seq, ",noextent_cache");
690 	seq_printf(seq, ",active_logs=%u", sbi->active_logs);
691 
692 	return 0;
693 }
694 
695 static int segment_info_seq_show(struct seq_file *seq, void *offset)
696 {
697 	struct super_block *sb = seq->private;
698 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
699 	unsigned int total_segs =
700 			le32_to_cpu(sbi->raw_super->segment_count_main);
701 	int i;
702 
703 	seq_puts(seq, "format: segment_type|valid_blocks\n"
704 		"segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
705 
706 	for (i = 0; i < total_segs; i++) {
707 		struct seg_entry *se = get_seg_entry(sbi, i);
708 
709 		if ((i % 10) == 0)
710 			seq_printf(seq, "%-10d", i);
711 		seq_printf(seq, "%d|%-3u", se->type,
712 					get_valid_blocks(sbi, i, 1));
713 		if ((i % 10) == 9 || i == (total_segs - 1))
714 			seq_putc(seq, '\n');
715 		else
716 			seq_putc(seq, ' ');
717 	}
718 
719 	return 0;
720 }
721 
722 static int segment_info_open_fs(struct inode *inode, struct file *file)
723 {
724 	return single_open(file, segment_info_seq_show, PDE_DATA(inode));
725 }
726 
727 static const struct file_operations f2fs_seq_segment_info_fops = {
728 	.owner = THIS_MODULE,
729 	.open = segment_info_open_fs,
730 	.read = seq_read,
731 	.llseek = seq_lseek,
732 	.release = single_release,
733 };
734 
735 static void default_options(struct f2fs_sb_info *sbi)
736 {
737 	/* init some FS parameters */
738 	sbi->active_logs = NR_CURSEG_TYPE;
739 
740 	set_opt(sbi, BG_GC);
741 	set_opt(sbi, INLINE_DATA);
742 	set_opt(sbi, EXTENT_CACHE);
743 
744 #ifdef CONFIG_F2FS_FS_XATTR
745 	set_opt(sbi, XATTR_USER);
746 #endif
747 #ifdef CONFIG_F2FS_FS_POSIX_ACL
748 	set_opt(sbi, POSIX_ACL);
749 #endif
750 }
751 
752 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
753 {
754 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
755 	struct f2fs_mount_info org_mount_opt;
756 	int err, active_logs;
757 	bool need_restart_gc = false;
758 	bool need_stop_gc = false;
759 	bool no_extent_cache = !test_opt(sbi, EXTENT_CACHE);
760 
761 	sync_filesystem(sb);
762 
763 	/*
764 	 * Save the old mount options in case we
765 	 * need to restore them.
766 	 */
767 	org_mount_opt = sbi->mount_opt;
768 	active_logs = sbi->active_logs;
769 
770 	sbi->mount_opt.opt = 0;
771 	default_options(sbi);
772 
773 	/* parse mount options */
774 	err = parse_options(sb, data);
775 	if (err)
776 		goto restore_opts;
777 
778 	/*
779 	 * Previous and new state of filesystem is RO,
780 	 * so skip checking GC and FLUSH_MERGE conditions.
781 	 */
782 	if (f2fs_readonly(sb) && (*flags & MS_RDONLY))
783 		goto skip;
784 
785 	/* disallow enable/disable extent_cache dynamically */
786 	if (no_extent_cache == !!test_opt(sbi, EXTENT_CACHE)) {
787 		err = -EINVAL;
788 		f2fs_msg(sbi->sb, KERN_WARNING,
789 				"switch extent_cache option is not allowed");
790 		goto restore_opts;
791 	}
792 
793 	/*
794 	 * We stop the GC thread if FS is mounted as RO
795 	 * or if background_gc = off is passed in mount
796 	 * option. Also sync the filesystem.
797 	 */
798 	if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
799 		if (sbi->gc_thread) {
800 			stop_gc_thread(sbi);
801 			f2fs_sync_fs(sb, 1);
802 			need_restart_gc = true;
803 		}
804 	} else if (!sbi->gc_thread) {
805 		err = start_gc_thread(sbi);
806 		if (err)
807 			goto restore_opts;
808 		need_stop_gc = true;
809 	}
810 
811 	/*
812 	 * We stop issue flush thread if FS is mounted as RO
813 	 * or if flush_merge is not passed in mount option.
814 	 */
815 	if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
816 		destroy_flush_cmd_control(sbi);
817 	} else if (!SM_I(sbi)->cmd_control_info) {
818 		err = create_flush_cmd_control(sbi);
819 		if (err)
820 			goto restore_gc;
821 	}
822 skip:
823 	/* Update the POSIXACL Flag */
824 	 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
825 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
826 	return 0;
827 restore_gc:
828 	if (need_restart_gc) {
829 		if (start_gc_thread(sbi))
830 			f2fs_msg(sbi->sb, KERN_WARNING,
831 				"background gc thread has stopped");
832 	} else if (need_stop_gc) {
833 		stop_gc_thread(sbi);
834 	}
835 restore_opts:
836 	sbi->mount_opt = org_mount_opt;
837 	sbi->active_logs = active_logs;
838 	return err;
839 }
840 
841 static struct super_operations f2fs_sops = {
842 	.alloc_inode	= f2fs_alloc_inode,
843 	.drop_inode	= f2fs_drop_inode,
844 	.destroy_inode	= f2fs_destroy_inode,
845 	.write_inode	= f2fs_write_inode,
846 	.dirty_inode	= f2fs_dirty_inode,
847 	.show_options	= f2fs_show_options,
848 	.evict_inode	= f2fs_evict_inode,
849 	.put_super	= f2fs_put_super,
850 	.sync_fs	= f2fs_sync_fs,
851 	.freeze_fs	= f2fs_freeze,
852 	.unfreeze_fs	= f2fs_unfreeze,
853 	.statfs		= f2fs_statfs,
854 	.remount_fs	= f2fs_remount,
855 };
856 
857 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
858 		u64 ino, u32 generation)
859 {
860 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
861 	struct inode *inode;
862 
863 	if (check_nid_range(sbi, ino))
864 		return ERR_PTR(-ESTALE);
865 
866 	/*
867 	 * f2fs_iget isn't quite right if the inode is currently unallocated!
868 	 * However f2fs_iget currently does appropriate checks to handle stale
869 	 * inodes so everything is OK.
870 	 */
871 	inode = f2fs_iget(sb, ino);
872 	if (IS_ERR(inode))
873 		return ERR_CAST(inode);
874 	if (unlikely(generation && inode->i_generation != generation)) {
875 		/* we didn't find the right inode.. */
876 		iput(inode);
877 		return ERR_PTR(-ESTALE);
878 	}
879 	return inode;
880 }
881 
882 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
883 		int fh_len, int fh_type)
884 {
885 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
886 				    f2fs_nfs_get_inode);
887 }
888 
889 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
890 		int fh_len, int fh_type)
891 {
892 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
893 				    f2fs_nfs_get_inode);
894 }
895 
896 static const struct export_operations f2fs_export_ops = {
897 	.fh_to_dentry = f2fs_fh_to_dentry,
898 	.fh_to_parent = f2fs_fh_to_parent,
899 	.get_parent = f2fs_get_parent,
900 };
901 
902 static loff_t max_file_size(unsigned bits)
903 {
904 	loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
905 	loff_t leaf_count = ADDRS_PER_BLOCK;
906 
907 	/* two direct node blocks */
908 	result += (leaf_count * 2);
909 
910 	/* two indirect node blocks */
911 	leaf_count *= NIDS_PER_BLOCK;
912 	result += (leaf_count * 2);
913 
914 	/* one double indirect node block */
915 	leaf_count *= NIDS_PER_BLOCK;
916 	result += leaf_count;
917 
918 	result <<= bits;
919 	return result;
920 }
921 
922 static inline bool sanity_check_area_boundary(struct super_block *sb,
923 					struct f2fs_super_block *raw_super)
924 {
925 	u32 segment0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
926 	u32 cp_blkaddr = le32_to_cpu(raw_super->cp_blkaddr);
927 	u32 sit_blkaddr = le32_to_cpu(raw_super->sit_blkaddr);
928 	u32 nat_blkaddr = le32_to_cpu(raw_super->nat_blkaddr);
929 	u32 ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
930 	u32 main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
931 	u32 segment_count_ckpt = le32_to_cpu(raw_super->segment_count_ckpt);
932 	u32 segment_count_sit = le32_to_cpu(raw_super->segment_count_sit);
933 	u32 segment_count_nat = le32_to_cpu(raw_super->segment_count_nat);
934 	u32 segment_count_ssa = le32_to_cpu(raw_super->segment_count_ssa);
935 	u32 segment_count_main = le32_to_cpu(raw_super->segment_count_main);
936 	u32 segment_count = le32_to_cpu(raw_super->segment_count);
937 	u32 log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
938 
939 	if (segment0_blkaddr != cp_blkaddr) {
940 		f2fs_msg(sb, KERN_INFO,
941 			"Mismatch start address, segment0(%u) cp_blkaddr(%u)",
942 			segment0_blkaddr, cp_blkaddr);
943 		return true;
944 	}
945 
946 	if (cp_blkaddr + (segment_count_ckpt << log_blocks_per_seg) !=
947 							sit_blkaddr) {
948 		f2fs_msg(sb, KERN_INFO,
949 			"Wrong CP boundary, start(%u) end(%u) blocks(%u)",
950 			cp_blkaddr, sit_blkaddr,
951 			segment_count_ckpt << log_blocks_per_seg);
952 		return true;
953 	}
954 
955 	if (sit_blkaddr + (segment_count_sit << log_blocks_per_seg) !=
956 							nat_blkaddr) {
957 		f2fs_msg(sb, KERN_INFO,
958 			"Wrong SIT boundary, start(%u) end(%u) blocks(%u)",
959 			sit_blkaddr, nat_blkaddr,
960 			segment_count_sit << log_blocks_per_seg);
961 		return true;
962 	}
963 
964 	if (nat_blkaddr + (segment_count_nat << log_blocks_per_seg) !=
965 							ssa_blkaddr) {
966 		f2fs_msg(sb, KERN_INFO,
967 			"Wrong NAT boundary, start(%u) end(%u) blocks(%u)",
968 			nat_blkaddr, ssa_blkaddr,
969 			segment_count_nat << log_blocks_per_seg);
970 		return true;
971 	}
972 
973 	if (ssa_blkaddr + (segment_count_ssa << log_blocks_per_seg) !=
974 							main_blkaddr) {
975 		f2fs_msg(sb, KERN_INFO,
976 			"Wrong SSA boundary, start(%u) end(%u) blocks(%u)",
977 			ssa_blkaddr, main_blkaddr,
978 			segment_count_ssa << log_blocks_per_seg);
979 		return true;
980 	}
981 
982 	if (main_blkaddr + (segment_count_main << log_blocks_per_seg) !=
983 		segment0_blkaddr + (segment_count << log_blocks_per_seg)) {
984 		f2fs_msg(sb, KERN_INFO,
985 			"Wrong MAIN_AREA boundary, start(%u) end(%u) blocks(%u)",
986 			main_blkaddr,
987 			segment0_blkaddr + (segment_count << log_blocks_per_seg),
988 			segment_count_main << log_blocks_per_seg);
989 		return true;
990 	}
991 
992 	return false;
993 }
994 
995 static int sanity_check_raw_super(struct super_block *sb,
996 			struct f2fs_super_block *raw_super)
997 {
998 	unsigned int blocksize;
999 
1000 	if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
1001 		f2fs_msg(sb, KERN_INFO,
1002 			"Magic Mismatch, valid(0x%x) - read(0x%x)",
1003 			F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
1004 		return 1;
1005 	}
1006 
1007 	/* Currently, support only 4KB page cache size */
1008 	if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
1009 		f2fs_msg(sb, KERN_INFO,
1010 			"Invalid page_cache_size (%lu), supports only 4KB\n",
1011 			PAGE_CACHE_SIZE);
1012 		return 1;
1013 	}
1014 
1015 	/* Currently, support only 4KB block size */
1016 	blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
1017 	if (blocksize != F2FS_BLKSIZE) {
1018 		f2fs_msg(sb, KERN_INFO,
1019 			"Invalid blocksize (%u), supports only 4KB\n",
1020 			blocksize);
1021 		return 1;
1022 	}
1023 
1024 	/* check log blocks per segment */
1025 	if (le32_to_cpu(raw_super->log_blocks_per_seg) != 9) {
1026 		f2fs_msg(sb, KERN_INFO,
1027 			"Invalid log blocks per segment (%u)\n",
1028 			le32_to_cpu(raw_super->log_blocks_per_seg));
1029 		return 1;
1030 	}
1031 
1032 	/* Currently, support 512/1024/2048/4096 bytes sector size */
1033 	if (le32_to_cpu(raw_super->log_sectorsize) >
1034 				F2FS_MAX_LOG_SECTOR_SIZE ||
1035 		le32_to_cpu(raw_super->log_sectorsize) <
1036 				F2FS_MIN_LOG_SECTOR_SIZE) {
1037 		f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize (%u)",
1038 			le32_to_cpu(raw_super->log_sectorsize));
1039 		return 1;
1040 	}
1041 	if (le32_to_cpu(raw_super->log_sectors_per_block) +
1042 		le32_to_cpu(raw_super->log_sectorsize) !=
1043 			F2FS_MAX_LOG_SECTOR_SIZE) {
1044 		f2fs_msg(sb, KERN_INFO,
1045 			"Invalid log sectors per block(%u) log sectorsize(%u)",
1046 			le32_to_cpu(raw_super->log_sectors_per_block),
1047 			le32_to_cpu(raw_super->log_sectorsize));
1048 		return 1;
1049 	}
1050 
1051 	/* check reserved ino info */
1052 	if (le32_to_cpu(raw_super->node_ino) != 1 ||
1053 		le32_to_cpu(raw_super->meta_ino) != 2 ||
1054 		le32_to_cpu(raw_super->root_ino) != 3) {
1055 		f2fs_msg(sb, KERN_INFO,
1056 			"Invalid Fs Meta Ino: node(%u) meta(%u) root(%u)",
1057 			le32_to_cpu(raw_super->node_ino),
1058 			le32_to_cpu(raw_super->meta_ino),
1059 			le32_to_cpu(raw_super->root_ino));
1060 		return 1;
1061 	}
1062 
1063 	/* check CP/SIT/NAT/SSA/MAIN_AREA area boundary */
1064 	if (sanity_check_area_boundary(sb, raw_super))
1065 		return 1;
1066 
1067 	return 0;
1068 }
1069 
1070 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
1071 {
1072 	unsigned int total, fsmeta;
1073 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
1074 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1075 
1076 	total = le32_to_cpu(raw_super->segment_count);
1077 	fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
1078 	fsmeta += le32_to_cpu(raw_super->segment_count_sit);
1079 	fsmeta += le32_to_cpu(raw_super->segment_count_nat);
1080 	fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
1081 	fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
1082 
1083 	if (unlikely(fsmeta >= total))
1084 		return 1;
1085 
1086 	if (unlikely(f2fs_cp_error(sbi))) {
1087 		f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
1088 		return 1;
1089 	}
1090 	return 0;
1091 }
1092 
1093 static void init_sb_info(struct f2fs_sb_info *sbi)
1094 {
1095 	struct f2fs_super_block *raw_super = sbi->raw_super;
1096 	int i;
1097 
1098 	sbi->log_sectors_per_block =
1099 		le32_to_cpu(raw_super->log_sectors_per_block);
1100 	sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
1101 	sbi->blocksize = 1 << sbi->log_blocksize;
1102 	sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
1103 	sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
1104 	sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
1105 	sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
1106 	sbi->total_sections = le32_to_cpu(raw_super->section_count);
1107 	sbi->total_node_count =
1108 		(le32_to_cpu(raw_super->segment_count_nat) / 2)
1109 			* sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
1110 	sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
1111 	sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
1112 	sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
1113 	sbi->cur_victim_sec = NULL_SECNO;
1114 	sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
1115 
1116 	for (i = 0; i < NR_COUNT_TYPE; i++)
1117 		atomic_set(&sbi->nr_pages[i], 0);
1118 
1119 	sbi->dir_level = DEF_DIR_LEVEL;
1120 	sbi->cp_interval = DEF_CP_INTERVAL;
1121 	clear_sbi_flag(sbi, SBI_NEED_FSCK);
1122 
1123 	INIT_LIST_HEAD(&sbi->s_list);
1124 	mutex_init(&sbi->umount_mutex);
1125 }
1126 
1127 /*
1128  * Read f2fs raw super block.
1129  * Because we have two copies of super block, so read the first one at first,
1130  * if the first one is invalid, move to read the second one.
1131  */
1132 static int read_raw_super_block(struct super_block *sb,
1133 			struct f2fs_super_block **raw_super,
1134 			int *valid_super_block, int *recovery)
1135 {
1136 	int block = 0;
1137 	struct buffer_head *bh;
1138 	struct f2fs_super_block *super, *buf;
1139 	int err = 0;
1140 
1141 	super = kzalloc(sizeof(struct f2fs_super_block), GFP_KERNEL);
1142 	if (!super)
1143 		return -ENOMEM;
1144 retry:
1145 	bh = sb_bread(sb, block);
1146 	if (!bh) {
1147 		*recovery = 1;
1148 		f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
1149 				block + 1);
1150 		err = -EIO;
1151 		goto next;
1152 	}
1153 
1154 	buf = (struct f2fs_super_block *)(bh->b_data + F2FS_SUPER_OFFSET);
1155 
1156 	/* sanity checking of raw super */
1157 	if (sanity_check_raw_super(sb, buf)) {
1158 		brelse(bh);
1159 		*recovery = 1;
1160 		f2fs_msg(sb, KERN_ERR,
1161 			"Can't find valid F2FS filesystem in %dth superblock",
1162 								block + 1);
1163 		err = -EINVAL;
1164 		goto next;
1165 	}
1166 
1167 	if (!*raw_super) {
1168 		memcpy(super, buf, sizeof(*super));
1169 		*valid_super_block = block;
1170 		*raw_super = super;
1171 	}
1172 	brelse(bh);
1173 
1174 next:
1175 	/* check the validity of the second superblock */
1176 	if (block == 0) {
1177 		block++;
1178 		goto retry;
1179 	}
1180 
1181 	/* No valid superblock */
1182 	if (!*raw_super) {
1183 		kfree(super);
1184 		return err;
1185 	}
1186 
1187 	return 0;
1188 }
1189 
1190 int __f2fs_commit_super(struct f2fs_sb_info *sbi, int block)
1191 {
1192 	struct f2fs_super_block *super = F2FS_RAW_SUPER(sbi);
1193 	struct buffer_head *bh;
1194 	int err;
1195 
1196 	bh = sb_getblk(sbi->sb, block);
1197 	if (!bh)
1198 		return -EIO;
1199 
1200 	lock_buffer(bh);
1201 	memcpy(bh->b_data + F2FS_SUPER_OFFSET, super, sizeof(*super));
1202 	set_buffer_uptodate(bh);
1203 	set_buffer_dirty(bh);
1204 	unlock_buffer(bh);
1205 
1206 	/* it's rare case, we can do fua all the time */
1207 	err = __sync_dirty_buffer(bh, WRITE_FLUSH_FUA);
1208 	brelse(bh);
1209 
1210 	return err;
1211 }
1212 
1213 int f2fs_commit_super(struct f2fs_sb_info *sbi, bool recover)
1214 {
1215 	int err;
1216 
1217 	/* write back-up superblock first */
1218 	err = __f2fs_commit_super(sbi, sbi->valid_super_block ? 0 : 1);
1219 
1220 	/* if we are in recovery path, skip writing valid superblock */
1221 	if (recover || err)
1222 		return err;
1223 
1224 	/* write current valid superblock */
1225 	return __f2fs_commit_super(sbi, sbi->valid_super_block);
1226 }
1227 
1228 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
1229 {
1230 	struct f2fs_sb_info *sbi;
1231 	struct f2fs_super_block *raw_super;
1232 	struct inode *root;
1233 	long err;
1234 	bool retry = true, need_fsck = false;
1235 	char *options = NULL;
1236 	int recovery, i, valid_super_block;
1237 
1238 try_onemore:
1239 	err = -EINVAL;
1240 	raw_super = NULL;
1241 	valid_super_block = -1;
1242 	recovery = 0;
1243 
1244 	/* allocate memory for f2fs-specific super block info */
1245 	sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
1246 	if (!sbi)
1247 		return -ENOMEM;
1248 
1249 	/* set a block size */
1250 	if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
1251 		f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
1252 		goto free_sbi;
1253 	}
1254 
1255 	err = read_raw_super_block(sb, &raw_super, &valid_super_block,
1256 								&recovery);
1257 	if (err)
1258 		goto free_sbi;
1259 
1260 	sb->s_fs_info = sbi;
1261 	default_options(sbi);
1262 	/* parse mount options */
1263 	options = kstrdup((const char *)data, GFP_KERNEL);
1264 	if (data && !options) {
1265 		err = -ENOMEM;
1266 		goto free_sb_buf;
1267 	}
1268 
1269 	err = parse_options(sb, options);
1270 	if (err)
1271 		goto free_options;
1272 
1273 	sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
1274 	sb->s_max_links = F2FS_LINK_MAX;
1275 	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1276 
1277 	sb->s_op = &f2fs_sops;
1278 	sb->s_xattr = f2fs_xattr_handlers;
1279 	sb->s_export_op = &f2fs_export_ops;
1280 	sb->s_magic = F2FS_SUPER_MAGIC;
1281 	sb->s_time_gran = 1;
1282 	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1283 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
1284 	memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
1285 
1286 	/* init f2fs-specific super block info */
1287 	sbi->sb = sb;
1288 	sbi->raw_super = raw_super;
1289 	sbi->valid_super_block = valid_super_block;
1290 	mutex_init(&sbi->gc_mutex);
1291 	mutex_init(&sbi->writepages);
1292 	mutex_init(&sbi->cp_mutex);
1293 	init_rwsem(&sbi->node_write);
1294 
1295 	/* disallow all the data/node/meta page writes */
1296 	set_sbi_flag(sbi, SBI_POR_DOING);
1297 	spin_lock_init(&sbi->stat_lock);
1298 
1299 	init_rwsem(&sbi->read_io.io_rwsem);
1300 	sbi->read_io.sbi = sbi;
1301 	sbi->read_io.bio = NULL;
1302 	for (i = 0; i < NR_PAGE_TYPE; i++) {
1303 		init_rwsem(&sbi->write_io[i].io_rwsem);
1304 		sbi->write_io[i].sbi = sbi;
1305 		sbi->write_io[i].bio = NULL;
1306 	}
1307 
1308 	init_rwsem(&sbi->cp_rwsem);
1309 	init_waitqueue_head(&sbi->cp_wait);
1310 	init_sb_info(sbi);
1311 
1312 	/* get an inode for meta space */
1313 	sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
1314 	if (IS_ERR(sbi->meta_inode)) {
1315 		f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
1316 		err = PTR_ERR(sbi->meta_inode);
1317 		goto free_options;
1318 	}
1319 
1320 	err = get_valid_checkpoint(sbi);
1321 	if (err) {
1322 		f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
1323 		goto free_meta_inode;
1324 	}
1325 
1326 	/* sanity checking of checkpoint */
1327 	err = -EINVAL;
1328 	if (sanity_check_ckpt(sbi)) {
1329 		f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
1330 		goto free_cp;
1331 	}
1332 
1333 	sbi->total_valid_node_count =
1334 				le32_to_cpu(sbi->ckpt->valid_node_count);
1335 	sbi->total_valid_inode_count =
1336 				le32_to_cpu(sbi->ckpt->valid_inode_count);
1337 	sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
1338 	sbi->total_valid_block_count =
1339 				le64_to_cpu(sbi->ckpt->valid_block_count);
1340 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1341 	sbi->alloc_valid_block_count = 0;
1342 	INIT_LIST_HEAD(&sbi->dir_inode_list);
1343 	spin_lock_init(&sbi->dir_inode_lock);
1344 
1345 	init_extent_cache_info(sbi);
1346 
1347 	init_ino_entry_info(sbi);
1348 
1349 	/* setup f2fs internal modules */
1350 	err = build_segment_manager(sbi);
1351 	if (err) {
1352 		f2fs_msg(sb, KERN_ERR,
1353 			"Failed to initialize F2FS segment manager");
1354 		goto free_sm;
1355 	}
1356 	err = build_node_manager(sbi);
1357 	if (err) {
1358 		f2fs_msg(sb, KERN_ERR,
1359 			"Failed to initialize F2FS node manager");
1360 		goto free_nm;
1361 	}
1362 
1363 	build_gc_manager(sbi);
1364 
1365 	/* get an inode for node space */
1366 	sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1367 	if (IS_ERR(sbi->node_inode)) {
1368 		f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1369 		err = PTR_ERR(sbi->node_inode);
1370 		goto free_nm;
1371 	}
1372 
1373 	f2fs_join_shrinker(sbi);
1374 
1375 	/* if there are nt orphan nodes free them */
1376 	err = recover_orphan_inodes(sbi);
1377 	if (err)
1378 		goto free_node_inode;
1379 
1380 	/* read root inode and dentry */
1381 	root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1382 	if (IS_ERR(root)) {
1383 		f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1384 		err = PTR_ERR(root);
1385 		goto free_node_inode;
1386 	}
1387 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1388 		iput(root);
1389 		err = -EINVAL;
1390 		goto free_node_inode;
1391 	}
1392 
1393 	sb->s_root = d_make_root(root); /* allocate root dentry */
1394 	if (!sb->s_root) {
1395 		err = -ENOMEM;
1396 		goto free_root_inode;
1397 	}
1398 
1399 	err = f2fs_build_stats(sbi);
1400 	if (err)
1401 		goto free_root_inode;
1402 
1403 	if (f2fs_proc_root)
1404 		sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1405 
1406 	if (sbi->s_proc)
1407 		proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1408 				 &f2fs_seq_segment_info_fops, sb);
1409 
1410 	sbi->s_kobj.kset = f2fs_kset;
1411 	init_completion(&sbi->s_kobj_unregister);
1412 	err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1413 							"%s", sb->s_id);
1414 	if (err)
1415 		goto free_proc;
1416 
1417 	/* recover fsynced data */
1418 	if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1419 		/*
1420 		 * mount should be failed, when device has readonly mode, and
1421 		 * previous checkpoint was not done by clean system shutdown.
1422 		 */
1423 		if (bdev_read_only(sb->s_bdev) &&
1424 				!is_set_ckpt_flags(sbi->ckpt, CP_UMOUNT_FLAG)) {
1425 			err = -EROFS;
1426 			goto free_kobj;
1427 		}
1428 
1429 		if (need_fsck)
1430 			set_sbi_flag(sbi, SBI_NEED_FSCK);
1431 
1432 		err = recover_fsync_data(sbi);
1433 		if (err) {
1434 			need_fsck = true;
1435 			f2fs_msg(sb, KERN_ERR,
1436 				"Cannot recover all fsync data errno=%ld", err);
1437 			goto free_kobj;
1438 		}
1439 	}
1440 	/* recover_fsync_data() cleared this already */
1441 	clear_sbi_flag(sbi, SBI_POR_DOING);
1442 
1443 	/*
1444 	 * If filesystem is not mounted as read-only then
1445 	 * do start the gc_thread.
1446 	 */
1447 	if (test_opt(sbi, BG_GC) && !f2fs_readonly(sb)) {
1448 		/* After POR, we can run background GC thread.*/
1449 		err = start_gc_thread(sbi);
1450 		if (err)
1451 			goto free_kobj;
1452 	}
1453 	kfree(options);
1454 
1455 	/* recover broken superblock */
1456 	if (recovery && !f2fs_readonly(sb) && !bdev_read_only(sb->s_bdev)) {
1457 		f2fs_msg(sb, KERN_INFO, "Recover invalid superblock");
1458 		f2fs_commit_super(sbi, true);
1459 	}
1460 
1461 	sbi->cp_expires = round_jiffies_up(jiffies);
1462 
1463 	return 0;
1464 
1465 free_kobj:
1466 	kobject_del(&sbi->s_kobj);
1467 	kobject_put(&sbi->s_kobj);
1468 	wait_for_completion(&sbi->s_kobj_unregister);
1469 free_proc:
1470 	if (sbi->s_proc) {
1471 		remove_proc_entry("segment_info", sbi->s_proc);
1472 		remove_proc_entry(sb->s_id, f2fs_proc_root);
1473 	}
1474 	f2fs_destroy_stats(sbi);
1475 free_root_inode:
1476 	dput(sb->s_root);
1477 	sb->s_root = NULL;
1478 free_node_inode:
1479 	mutex_lock(&sbi->umount_mutex);
1480 	f2fs_leave_shrinker(sbi);
1481 	iput(sbi->node_inode);
1482 	mutex_unlock(&sbi->umount_mutex);
1483 free_nm:
1484 	destroy_node_manager(sbi);
1485 free_sm:
1486 	destroy_segment_manager(sbi);
1487 free_cp:
1488 	kfree(sbi->ckpt);
1489 free_meta_inode:
1490 	make_bad_inode(sbi->meta_inode);
1491 	iput(sbi->meta_inode);
1492 free_options:
1493 	kfree(options);
1494 free_sb_buf:
1495 	kfree(raw_super);
1496 free_sbi:
1497 	kfree(sbi);
1498 
1499 	/* give only one another chance */
1500 	if (retry) {
1501 		retry = false;
1502 		shrink_dcache_sb(sb);
1503 		goto try_onemore;
1504 	}
1505 	return err;
1506 }
1507 
1508 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1509 			const char *dev_name, void *data)
1510 {
1511 	return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1512 }
1513 
1514 static void kill_f2fs_super(struct super_block *sb)
1515 {
1516 	if (sb->s_root)
1517 		set_sbi_flag(F2FS_SB(sb), SBI_IS_CLOSE);
1518 	kill_block_super(sb);
1519 }
1520 
1521 static struct file_system_type f2fs_fs_type = {
1522 	.owner		= THIS_MODULE,
1523 	.name		= "f2fs",
1524 	.mount		= f2fs_mount,
1525 	.kill_sb	= kill_f2fs_super,
1526 	.fs_flags	= FS_REQUIRES_DEV,
1527 };
1528 MODULE_ALIAS_FS("f2fs");
1529 
1530 static int __init init_inodecache(void)
1531 {
1532 	f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1533 			sizeof(struct f2fs_inode_info));
1534 	if (!f2fs_inode_cachep)
1535 		return -ENOMEM;
1536 	return 0;
1537 }
1538 
1539 static void destroy_inodecache(void)
1540 {
1541 	/*
1542 	 * Make sure all delayed rcu free inodes are flushed before we
1543 	 * destroy cache.
1544 	 */
1545 	rcu_barrier();
1546 	kmem_cache_destroy(f2fs_inode_cachep);
1547 }
1548 
1549 static int __init init_f2fs_fs(void)
1550 {
1551 	int err;
1552 
1553 	f2fs_build_trace_ios();
1554 
1555 	err = init_inodecache();
1556 	if (err)
1557 		goto fail;
1558 	err = create_node_manager_caches();
1559 	if (err)
1560 		goto free_inodecache;
1561 	err = create_segment_manager_caches();
1562 	if (err)
1563 		goto free_node_manager_caches;
1564 	err = create_checkpoint_caches();
1565 	if (err)
1566 		goto free_segment_manager_caches;
1567 	err = create_extent_cache();
1568 	if (err)
1569 		goto free_checkpoint_caches;
1570 	f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1571 	if (!f2fs_kset) {
1572 		err = -ENOMEM;
1573 		goto free_extent_cache;
1574 	}
1575 	err = f2fs_init_crypto();
1576 	if (err)
1577 		goto free_kset;
1578 
1579 	err = register_shrinker(&f2fs_shrinker_info);
1580 	if (err)
1581 		goto free_crypto;
1582 
1583 	err = register_filesystem(&f2fs_fs_type);
1584 	if (err)
1585 		goto free_shrinker;
1586 	err = f2fs_create_root_stats();
1587 	if (err)
1588 		goto free_filesystem;
1589 	f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1590 	return 0;
1591 
1592 free_filesystem:
1593 	unregister_filesystem(&f2fs_fs_type);
1594 free_shrinker:
1595 	unregister_shrinker(&f2fs_shrinker_info);
1596 free_crypto:
1597 	f2fs_exit_crypto();
1598 free_kset:
1599 	kset_unregister(f2fs_kset);
1600 free_extent_cache:
1601 	destroy_extent_cache();
1602 free_checkpoint_caches:
1603 	destroy_checkpoint_caches();
1604 free_segment_manager_caches:
1605 	destroy_segment_manager_caches();
1606 free_node_manager_caches:
1607 	destroy_node_manager_caches();
1608 free_inodecache:
1609 	destroy_inodecache();
1610 fail:
1611 	return err;
1612 }
1613 
1614 static void __exit exit_f2fs_fs(void)
1615 {
1616 	remove_proc_entry("fs/f2fs", NULL);
1617 	f2fs_destroy_root_stats();
1618 	unregister_shrinker(&f2fs_shrinker_info);
1619 	unregister_filesystem(&f2fs_fs_type);
1620 	f2fs_exit_crypto();
1621 	destroy_extent_cache();
1622 	destroy_checkpoint_caches();
1623 	destroy_segment_manager_caches();
1624 	destroy_node_manager_caches();
1625 	destroy_inodecache();
1626 	kset_unregister(f2fs_kset);
1627 	f2fs_destroy_trace_ios();
1628 }
1629 
1630 module_init(init_f2fs_fs)
1631 module_exit(exit_f2fs_fs)
1632 
1633 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1634 MODULE_DESCRIPTION("Flash Friendly File System");
1635 MODULE_LICENSE("GPL");
1636