xref: /openbmc/linux/fs/f2fs/super.c (revision 33ac9dba)
1 /*
2  * fs/f2fs/super.c
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/fs.h>
14 #include <linux/statfs.h>
15 #include <linux/buffer_head.h>
16 #include <linux/backing-dev.h>
17 #include <linux/kthread.h>
18 #include <linux/parser.h>
19 #include <linux/mount.h>
20 #include <linux/seq_file.h>
21 #include <linux/proc_fs.h>
22 #include <linux/random.h>
23 #include <linux/exportfs.h>
24 #include <linux/blkdev.h>
25 #include <linux/f2fs_fs.h>
26 #include <linux/sysfs.h>
27 
28 #include "f2fs.h"
29 #include "node.h"
30 #include "segment.h"
31 #include "xattr.h"
32 #include "gc.h"
33 
34 #define CREATE_TRACE_POINTS
35 #include <trace/events/f2fs.h>
36 
37 static struct proc_dir_entry *f2fs_proc_root;
38 static struct kmem_cache *f2fs_inode_cachep;
39 static struct kset *f2fs_kset;
40 
41 enum {
42 	Opt_gc_background,
43 	Opt_disable_roll_forward,
44 	Opt_discard,
45 	Opt_noheap,
46 	Opt_user_xattr,
47 	Opt_nouser_xattr,
48 	Opt_acl,
49 	Opt_noacl,
50 	Opt_active_logs,
51 	Opt_disable_ext_identify,
52 	Opt_inline_xattr,
53 	Opt_inline_data,
54 	Opt_flush_merge,
55 	Opt_nobarrier,
56 	Opt_err,
57 };
58 
59 static match_table_t f2fs_tokens = {
60 	{Opt_gc_background, "background_gc=%s"},
61 	{Opt_disable_roll_forward, "disable_roll_forward"},
62 	{Opt_discard, "discard"},
63 	{Opt_noheap, "no_heap"},
64 	{Opt_user_xattr, "user_xattr"},
65 	{Opt_nouser_xattr, "nouser_xattr"},
66 	{Opt_acl, "acl"},
67 	{Opt_noacl, "noacl"},
68 	{Opt_active_logs, "active_logs=%u"},
69 	{Opt_disable_ext_identify, "disable_ext_identify"},
70 	{Opt_inline_xattr, "inline_xattr"},
71 	{Opt_inline_data, "inline_data"},
72 	{Opt_flush_merge, "flush_merge"},
73 	{Opt_nobarrier, "nobarrier"},
74 	{Opt_err, NULL},
75 };
76 
77 /* Sysfs support for f2fs */
78 enum {
79 	GC_THREAD,	/* struct f2fs_gc_thread */
80 	SM_INFO,	/* struct f2fs_sm_info */
81 	NM_INFO,	/* struct f2fs_nm_info */
82 	F2FS_SBI,	/* struct f2fs_sb_info */
83 };
84 
85 struct f2fs_attr {
86 	struct attribute attr;
87 	ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
88 	ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
89 			 const char *, size_t);
90 	int struct_type;
91 	int offset;
92 };
93 
94 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
95 {
96 	if (struct_type == GC_THREAD)
97 		return (unsigned char *)sbi->gc_thread;
98 	else if (struct_type == SM_INFO)
99 		return (unsigned char *)SM_I(sbi);
100 	else if (struct_type == NM_INFO)
101 		return (unsigned char *)NM_I(sbi);
102 	else if (struct_type == F2FS_SBI)
103 		return (unsigned char *)sbi;
104 	return NULL;
105 }
106 
107 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
108 			struct f2fs_sb_info *sbi, char *buf)
109 {
110 	unsigned char *ptr = NULL;
111 	unsigned int *ui;
112 
113 	ptr = __struct_ptr(sbi, a->struct_type);
114 	if (!ptr)
115 		return -EINVAL;
116 
117 	ui = (unsigned int *)(ptr + a->offset);
118 
119 	return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
120 }
121 
122 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
123 			struct f2fs_sb_info *sbi,
124 			const char *buf, size_t count)
125 {
126 	unsigned char *ptr;
127 	unsigned long t;
128 	unsigned int *ui;
129 	ssize_t ret;
130 
131 	ptr = __struct_ptr(sbi, a->struct_type);
132 	if (!ptr)
133 		return -EINVAL;
134 
135 	ui = (unsigned int *)(ptr + a->offset);
136 
137 	ret = kstrtoul(skip_spaces(buf), 0, &t);
138 	if (ret < 0)
139 		return ret;
140 	*ui = t;
141 	return count;
142 }
143 
144 static ssize_t f2fs_attr_show(struct kobject *kobj,
145 				struct attribute *attr, char *buf)
146 {
147 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
148 								s_kobj);
149 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
150 
151 	return a->show ? a->show(a, sbi, buf) : 0;
152 }
153 
154 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
155 						const char *buf, size_t len)
156 {
157 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
158 									s_kobj);
159 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
160 
161 	return a->store ? a->store(a, sbi, buf, len) : 0;
162 }
163 
164 static void f2fs_sb_release(struct kobject *kobj)
165 {
166 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
167 								s_kobj);
168 	complete(&sbi->s_kobj_unregister);
169 }
170 
171 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
172 static struct f2fs_attr f2fs_attr_##_name = {			\
173 	.attr = {.name = __stringify(_name), .mode = _mode },	\
174 	.show	= _show,					\
175 	.store	= _store,					\
176 	.struct_type = _struct_type,				\
177 	.offset = _offset					\
178 }
179 
180 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)	\
181 	F2FS_ATTR_OFFSET(struct_type, name, 0644,		\
182 		f2fs_sbi_show, f2fs_sbi_store,			\
183 		offsetof(struct struct_name, elname))
184 
185 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
186 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
187 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
188 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
189 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
190 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
191 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
192 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
193 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
194 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
195 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
196 
197 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
198 static struct attribute *f2fs_attrs[] = {
199 	ATTR_LIST(gc_min_sleep_time),
200 	ATTR_LIST(gc_max_sleep_time),
201 	ATTR_LIST(gc_no_gc_sleep_time),
202 	ATTR_LIST(gc_idle),
203 	ATTR_LIST(reclaim_segments),
204 	ATTR_LIST(max_small_discards),
205 	ATTR_LIST(ipu_policy),
206 	ATTR_LIST(min_ipu_util),
207 	ATTR_LIST(max_victim_search),
208 	ATTR_LIST(dir_level),
209 	ATTR_LIST(ram_thresh),
210 	NULL,
211 };
212 
213 static const struct sysfs_ops f2fs_attr_ops = {
214 	.show	= f2fs_attr_show,
215 	.store	= f2fs_attr_store,
216 };
217 
218 static struct kobj_type f2fs_ktype = {
219 	.default_attrs	= f2fs_attrs,
220 	.sysfs_ops	= &f2fs_attr_ops,
221 	.release	= f2fs_sb_release,
222 };
223 
224 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
225 {
226 	struct va_format vaf;
227 	va_list args;
228 
229 	va_start(args, fmt);
230 	vaf.fmt = fmt;
231 	vaf.va = &args;
232 	printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
233 	va_end(args);
234 }
235 
236 static void init_once(void *foo)
237 {
238 	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
239 
240 	inode_init_once(&fi->vfs_inode);
241 }
242 
243 static int parse_options(struct super_block *sb, char *options)
244 {
245 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
246 	substring_t args[MAX_OPT_ARGS];
247 	char *p, *name;
248 	int arg = 0;
249 
250 	if (!options)
251 		return 0;
252 
253 	while ((p = strsep(&options, ",")) != NULL) {
254 		int token;
255 		if (!*p)
256 			continue;
257 		/*
258 		 * Initialize args struct so we know whether arg was
259 		 * found; some options take optional arguments.
260 		 */
261 		args[0].to = args[0].from = NULL;
262 		token = match_token(p, f2fs_tokens, args);
263 
264 		switch (token) {
265 		case Opt_gc_background:
266 			name = match_strdup(&args[0]);
267 
268 			if (!name)
269 				return -ENOMEM;
270 			if (strlen(name) == 2 && !strncmp(name, "on", 2))
271 				set_opt(sbi, BG_GC);
272 			else if (strlen(name) == 3 && !strncmp(name, "off", 3))
273 				clear_opt(sbi, BG_GC);
274 			else {
275 				kfree(name);
276 				return -EINVAL;
277 			}
278 			kfree(name);
279 			break;
280 		case Opt_disable_roll_forward:
281 			set_opt(sbi, DISABLE_ROLL_FORWARD);
282 			break;
283 		case Opt_discard:
284 			set_opt(sbi, DISCARD);
285 			break;
286 		case Opt_noheap:
287 			set_opt(sbi, NOHEAP);
288 			break;
289 #ifdef CONFIG_F2FS_FS_XATTR
290 		case Opt_user_xattr:
291 			set_opt(sbi, XATTR_USER);
292 			break;
293 		case Opt_nouser_xattr:
294 			clear_opt(sbi, XATTR_USER);
295 			break;
296 		case Opt_inline_xattr:
297 			set_opt(sbi, INLINE_XATTR);
298 			break;
299 #else
300 		case Opt_user_xattr:
301 			f2fs_msg(sb, KERN_INFO,
302 				"user_xattr options not supported");
303 			break;
304 		case Opt_nouser_xattr:
305 			f2fs_msg(sb, KERN_INFO,
306 				"nouser_xattr options not supported");
307 			break;
308 		case Opt_inline_xattr:
309 			f2fs_msg(sb, KERN_INFO,
310 				"inline_xattr options not supported");
311 			break;
312 #endif
313 #ifdef CONFIG_F2FS_FS_POSIX_ACL
314 		case Opt_acl:
315 			set_opt(sbi, POSIX_ACL);
316 			break;
317 		case Opt_noacl:
318 			clear_opt(sbi, POSIX_ACL);
319 			break;
320 #else
321 		case Opt_acl:
322 			f2fs_msg(sb, KERN_INFO, "acl options not supported");
323 			break;
324 		case Opt_noacl:
325 			f2fs_msg(sb, KERN_INFO, "noacl options not supported");
326 			break;
327 #endif
328 		case Opt_active_logs:
329 			if (args->from && match_int(args, &arg))
330 				return -EINVAL;
331 			if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
332 				return -EINVAL;
333 			sbi->active_logs = arg;
334 			break;
335 		case Opt_disable_ext_identify:
336 			set_opt(sbi, DISABLE_EXT_IDENTIFY);
337 			break;
338 		case Opt_inline_data:
339 			set_opt(sbi, INLINE_DATA);
340 			break;
341 		case Opt_flush_merge:
342 			set_opt(sbi, FLUSH_MERGE);
343 			break;
344 		case Opt_nobarrier:
345 			set_opt(sbi, NOBARRIER);
346 			break;
347 		default:
348 			f2fs_msg(sb, KERN_ERR,
349 				"Unrecognized mount option \"%s\" or missing value",
350 				p);
351 			return -EINVAL;
352 		}
353 	}
354 	return 0;
355 }
356 
357 static struct inode *f2fs_alloc_inode(struct super_block *sb)
358 {
359 	struct f2fs_inode_info *fi;
360 
361 	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
362 	if (!fi)
363 		return NULL;
364 
365 	init_once((void *) fi);
366 
367 	/* Initialize f2fs-specific inode info */
368 	fi->vfs_inode.i_version = 1;
369 	atomic_set(&fi->dirty_dents, 0);
370 	fi->i_current_depth = 1;
371 	fi->i_advise = 0;
372 	rwlock_init(&fi->ext.ext_lock);
373 	init_rwsem(&fi->i_sem);
374 
375 	set_inode_flag(fi, FI_NEW_INODE);
376 
377 	if (test_opt(F2FS_SB(sb), INLINE_XATTR))
378 		set_inode_flag(fi, FI_INLINE_XATTR);
379 
380 	/* Will be used by directory only */
381 	fi->i_dir_level = F2FS_SB(sb)->dir_level;
382 
383 	return &fi->vfs_inode;
384 }
385 
386 static int f2fs_drop_inode(struct inode *inode)
387 {
388 	/*
389 	 * This is to avoid a deadlock condition like below.
390 	 * writeback_single_inode(inode)
391 	 *  - f2fs_write_data_page
392 	 *    - f2fs_gc -> iput -> evict
393 	 *       - inode_wait_for_writeback(inode)
394 	 */
395 	if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
396 		return 0;
397 	return generic_drop_inode(inode);
398 }
399 
400 /*
401  * f2fs_dirty_inode() is called from __mark_inode_dirty()
402  *
403  * We should call set_dirty_inode to write the dirty inode through write_inode.
404  */
405 static void f2fs_dirty_inode(struct inode *inode, int flags)
406 {
407 	set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
408 }
409 
410 static void f2fs_i_callback(struct rcu_head *head)
411 {
412 	struct inode *inode = container_of(head, struct inode, i_rcu);
413 	kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
414 }
415 
416 static void f2fs_destroy_inode(struct inode *inode)
417 {
418 	call_rcu(&inode->i_rcu, f2fs_i_callback);
419 }
420 
421 static void f2fs_put_super(struct super_block *sb)
422 {
423 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
424 
425 	if (sbi->s_proc) {
426 		remove_proc_entry("segment_info", sbi->s_proc);
427 		remove_proc_entry(sb->s_id, f2fs_proc_root);
428 	}
429 	kobject_del(&sbi->s_kobj);
430 
431 	f2fs_destroy_stats(sbi);
432 	stop_gc_thread(sbi);
433 
434 	/* We don't need to do checkpoint when it's clean */
435 	if (sbi->s_dirty && get_pages(sbi, F2FS_DIRTY_NODES))
436 		write_checkpoint(sbi, true);
437 
438 	iput(sbi->node_inode);
439 	iput(sbi->meta_inode);
440 
441 	/* destroy f2fs internal modules */
442 	destroy_node_manager(sbi);
443 	destroy_segment_manager(sbi);
444 
445 	kfree(sbi->ckpt);
446 	kobject_put(&sbi->s_kobj);
447 	wait_for_completion(&sbi->s_kobj_unregister);
448 
449 	sb->s_fs_info = NULL;
450 	brelse(sbi->raw_super_buf);
451 	kfree(sbi);
452 }
453 
454 int f2fs_sync_fs(struct super_block *sb, int sync)
455 {
456 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
457 
458 	trace_f2fs_sync_fs(sb, sync);
459 
460 	if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
461 		return 0;
462 
463 	if (sync) {
464 		mutex_lock(&sbi->gc_mutex);
465 		write_checkpoint(sbi, false);
466 		mutex_unlock(&sbi->gc_mutex);
467 	} else {
468 		f2fs_balance_fs(sbi);
469 	}
470 
471 	return 0;
472 }
473 
474 static int f2fs_freeze(struct super_block *sb)
475 {
476 	int err;
477 
478 	if (f2fs_readonly(sb))
479 		return 0;
480 
481 	err = f2fs_sync_fs(sb, 1);
482 	return err;
483 }
484 
485 static int f2fs_unfreeze(struct super_block *sb)
486 {
487 	return 0;
488 }
489 
490 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
491 {
492 	struct super_block *sb = dentry->d_sb;
493 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
494 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
495 	block_t total_count, user_block_count, start_count, ovp_count;
496 
497 	total_count = le64_to_cpu(sbi->raw_super->block_count);
498 	user_block_count = sbi->user_block_count;
499 	start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
500 	ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
501 	buf->f_type = F2FS_SUPER_MAGIC;
502 	buf->f_bsize = sbi->blocksize;
503 
504 	buf->f_blocks = total_count - start_count;
505 	buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
506 	buf->f_bavail = user_block_count - valid_user_blocks(sbi);
507 
508 	buf->f_files = sbi->total_node_count;
509 	buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
510 
511 	buf->f_namelen = F2FS_NAME_LEN;
512 	buf->f_fsid.val[0] = (u32)id;
513 	buf->f_fsid.val[1] = (u32)(id >> 32);
514 
515 	return 0;
516 }
517 
518 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
519 {
520 	struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
521 
522 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC))
523 		seq_printf(seq, ",background_gc=%s", "on");
524 	else
525 		seq_printf(seq, ",background_gc=%s", "off");
526 	if (test_opt(sbi, DISABLE_ROLL_FORWARD))
527 		seq_puts(seq, ",disable_roll_forward");
528 	if (test_opt(sbi, DISCARD))
529 		seq_puts(seq, ",discard");
530 	if (test_opt(sbi, NOHEAP))
531 		seq_puts(seq, ",no_heap_alloc");
532 #ifdef CONFIG_F2FS_FS_XATTR
533 	if (test_opt(sbi, XATTR_USER))
534 		seq_puts(seq, ",user_xattr");
535 	else
536 		seq_puts(seq, ",nouser_xattr");
537 	if (test_opt(sbi, INLINE_XATTR))
538 		seq_puts(seq, ",inline_xattr");
539 #endif
540 #ifdef CONFIG_F2FS_FS_POSIX_ACL
541 	if (test_opt(sbi, POSIX_ACL))
542 		seq_puts(seq, ",acl");
543 	else
544 		seq_puts(seq, ",noacl");
545 #endif
546 	if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
547 		seq_puts(seq, ",disable_ext_identify");
548 	if (test_opt(sbi, INLINE_DATA))
549 		seq_puts(seq, ",inline_data");
550 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
551 		seq_puts(seq, ",flush_merge");
552 	if (test_opt(sbi, NOBARRIER))
553 		seq_puts(seq, ",nobarrier");
554 	seq_printf(seq, ",active_logs=%u", sbi->active_logs);
555 
556 	return 0;
557 }
558 
559 static int segment_info_seq_show(struct seq_file *seq, void *offset)
560 {
561 	struct super_block *sb = seq->private;
562 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
563 	unsigned int total_segs =
564 			le32_to_cpu(sbi->raw_super->segment_count_main);
565 	int i;
566 
567 	seq_puts(seq, "format: segment_type|valid_blocks\n"
568 		"segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
569 
570 	for (i = 0; i < total_segs; i++) {
571 		struct seg_entry *se = get_seg_entry(sbi, i);
572 
573 		if ((i % 10) == 0)
574 			seq_printf(seq, "%-5d", i);
575 		seq_printf(seq, "%d|%-3u", se->type,
576 					get_valid_blocks(sbi, i, 1));
577 		if ((i % 10) == 9 || i == (total_segs - 1))
578 			seq_putc(seq, '\n');
579 		else
580 			seq_putc(seq, ' ');
581 	}
582 
583 	return 0;
584 }
585 
586 static int segment_info_open_fs(struct inode *inode, struct file *file)
587 {
588 	return single_open(file, segment_info_seq_show, PDE_DATA(inode));
589 }
590 
591 static const struct file_operations f2fs_seq_segment_info_fops = {
592 	.owner = THIS_MODULE,
593 	.open = segment_info_open_fs,
594 	.read = seq_read,
595 	.llseek = seq_lseek,
596 	.release = single_release,
597 };
598 
599 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
600 {
601 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
602 	struct f2fs_mount_info org_mount_opt;
603 	int err, active_logs;
604 	bool need_restart_gc = false;
605 	bool need_stop_gc = false;
606 
607 	sync_filesystem(sb);
608 
609 	/*
610 	 * Save the old mount options in case we
611 	 * need to restore them.
612 	 */
613 	org_mount_opt = sbi->mount_opt;
614 	active_logs = sbi->active_logs;
615 
616 	/* parse mount options */
617 	err = parse_options(sb, data);
618 	if (err)
619 		goto restore_opts;
620 
621 	/*
622 	 * Previous and new state of filesystem is RO,
623 	 * so skip checking GC and FLUSH_MERGE conditions.
624 	 */
625 	if (f2fs_readonly(sb) && (*flags & MS_RDONLY))
626 		goto skip;
627 
628 	/*
629 	 * We stop the GC thread if FS is mounted as RO
630 	 * or if background_gc = off is passed in mount
631 	 * option. Also sync the filesystem.
632 	 */
633 	if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
634 		if (sbi->gc_thread) {
635 			stop_gc_thread(sbi);
636 			f2fs_sync_fs(sb, 1);
637 			need_restart_gc = true;
638 		}
639 	} else if (test_opt(sbi, BG_GC) && !sbi->gc_thread) {
640 		err = start_gc_thread(sbi);
641 		if (err)
642 			goto restore_opts;
643 		need_stop_gc = true;
644 	}
645 
646 	/*
647 	 * We stop issue flush thread if FS is mounted as RO
648 	 * or if flush_merge is not passed in mount option.
649 	 */
650 	if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
651 		destroy_flush_cmd_control(sbi);
652 	} else if (test_opt(sbi, FLUSH_MERGE) && !SM_I(sbi)->cmd_control_info) {
653 		err = create_flush_cmd_control(sbi);
654 		if (err)
655 			goto restore_gc;
656 	}
657 skip:
658 	/* Update the POSIXACL Flag */
659 	 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
660 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
661 	return 0;
662 restore_gc:
663 	if (need_restart_gc) {
664 		if (start_gc_thread(sbi))
665 			f2fs_msg(sbi->sb, KERN_WARNING,
666 				"background gc thread is stop");
667 	} else if (need_stop_gc) {
668 		stop_gc_thread(sbi);
669 	}
670 restore_opts:
671 	sbi->mount_opt = org_mount_opt;
672 	sbi->active_logs = active_logs;
673 	return err;
674 }
675 
676 static struct super_operations f2fs_sops = {
677 	.alloc_inode	= f2fs_alloc_inode,
678 	.drop_inode	= f2fs_drop_inode,
679 	.destroy_inode	= f2fs_destroy_inode,
680 	.write_inode	= f2fs_write_inode,
681 	.dirty_inode	= f2fs_dirty_inode,
682 	.show_options	= f2fs_show_options,
683 	.evict_inode	= f2fs_evict_inode,
684 	.put_super	= f2fs_put_super,
685 	.sync_fs	= f2fs_sync_fs,
686 	.freeze_fs	= f2fs_freeze,
687 	.unfreeze_fs	= f2fs_unfreeze,
688 	.statfs		= f2fs_statfs,
689 	.remount_fs	= f2fs_remount,
690 };
691 
692 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
693 		u64 ino, u32 generation)
694 {
695 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
696 	struct inode *inode;
697 
698 	if (check_nid_range(sbi, ino))
699 		return ERR_PTR(-ESTALE);
700 
701 	/*
702 	 * f2fs_iget isn't quite right if the inode is currently unallocated!
703 	 * However f2fs_iget currently does appropriate checks to handle stale
704 	 * inodes so everything is OK.
705 	 */
706 	inode = f2fs_iget(sb, ino);
707 	if (IS_ERR(inode))
708 		return ERR_CAST(inode);
709 	if (unlikely(generation && inode->i_generation != generation)) {
710 		/* we didn't find the right inode.. */
711 		iput(inode);
712 		return ERR_PTR(-ESTALE);
713 	}
714 	return inode;
715 }
716 
717 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
718 		int fh_len, int fh_type)
719 {
720 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
721 				    f2fs_nfs_get_inode);
722 }
723 
724 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
725 		int fh_len, int fh_type)
726 {
727 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
728 				    f2fs_nfs_get_inode);
729 }
730 
731 static const struct export_operations f2fs_export_ops = {
732 	.fh_to_dentry = f2fs_fh_to_dentry,
733 	.fh_to_parent = f2fs_fh_to_parent,
734 	.get_parent = f2fs_get_parent,
735 };
736 
737 static loff_t max_file_size(unsigned bits)
738 {
739 	loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
740 	loff_t leaf_count = ADDRS_PER_BLOCK;
741 
742 	/* two direct node blocks */
743 	result += (leaf_count * 2);
744 
745 	/* two indirect node blocks */
746 	leaf_count *= NIDS_PER_BLOCK;
747 	result += (leaf_count * 2);
748 
749 	/* one double indirect node block */
750 	leaf_count *= NIDS_PER_BLOCK;
751 	result += leaf_count;
752 
753 	result <<= bits;
754 	return result;
755 }
756 
757 static int sanity_check_raw_super(struct super_block *sb,
758 			struct f2fs_super_block *raw_super)
759 {
760 	unsigned int blocksize;
761 
762 	if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
763 		f2fs_msg(sb, KERN_INFO,
764 			"Magic Mismatch, valid(0x%x) - read(0x%x)",
765 			F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
766 		return 1;
767 	}
768 
769 	/* Currently, support only 4KB page cache size */
770 	if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
771 		f2fs_msg(sb, KERN_INFO,
772 			"Invalid page_cache_size (%lu), supports only 4KB\n",
773 			PAGE_CACHE_SIZE);
774 		return 1;
775 	}
776 
777 	/* Currently, support only 4KB block size */
778 	blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
779 	if (blocksize != F2FS_BLKSIZE) {
780 		f2fs_msg(sb, KERN_INFO,
781 			"Invalid blocksize (%u), supports only 4KB\n",
782 			blocksize);
783 		return 1;
784 	}
785 
786 	if (le32_to_cpu(raw_super->log_sectorsize) !=
787 					F2FS_LOG_SECTOR_SIZE) {
788 		f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
789 		return 1;
790 	}
791 	if (le32_to_cpu(raw_super->log_sectors_per_block) !=
792 					F2FS_LOG_SECTORS_PER_BLOCK) {
793 		f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
794 		return 1;
795 	}
796 	return 0;
797 }
798 
799 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
800 {
801 	unsigned int total, fsmeta;
802 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
803 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
804 
805 	total = le32_to_cpu(raw_super->segment_count);
806 	fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
807 	fsmeta += le32_to_cpu(raw_super->segment_count_sit);
808 	fsmeta += le32_to_cpu(raw_super->segment_count_nat);
809 	fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
810 	fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
811 
812 	if (unlikely(fsmeta >= total))
813 		return 1;
814 
815 	if (unlikely(is_set_ckpt_flags(ckpt, CP_ERROR_FLAG))) {
816 		f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
817 		return 1;
818 	}
819 	return 0;
820 }
821 
822 static void init_sb_info(struct f2fs_sb_info *sbi)
823 {
824 	struct f2fs_super_block *raw_super = sbi->raw_super;
825 	int i;
826 
827 	sbi->log_sectors_per_block =
828 		le32_to_cpu(raw_super->log_sectors_per_block);
829 	sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
830 	sbi->blocksize = 1 << sbi->log_blocksize;
831 	sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
832 	sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
833 	sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
834 	sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
835 	sbi->total_sections = le32_to_cpu(raw_super->section_count);
836 	sbi->total_node_count =
837 		(le32_to_cpu(raw_super->segment_count_nat) / 2)
838 			* sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
839 	sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
840 	sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
841 	sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
842 	sbi->cur_victim_sec = NULL_SECNO;
843 	sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
844 
845 	for (i = 0; i < NR_COUNT_TYPE; i++)
846 		atomic_set(&sbi->nr_pages[i], 0);
847 
848 	sbi->dir_level = DEF_DIR_LEVEL;
849 }
850 
851 /*
852  * Read f2fs raw super block.
853  * Because we have two copies of super block, so read the first one at first,
854  * if the first one is invalid, move to read the second one.
855  */
856 static int read_raw_super_block(struct super_block *sb,
857 			struct f2fs_super_block **raw_super,
858 			struct buffer_head **raw_super_buf)
859 {
860 	int block = 0;
861 
862 retry:
863 	*raw_super_buf = sb_bread(sb, block);
864 	if (!*raw_super_buf) {
865 		f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
866 				block + 1);
867 		if (block == 0) {
868 			block++;
869 			goto retry;
870 		} else {
871 			return -EIO;
872 		}
873 	}
874 
875 	*raw_super = (struct f2fs_super_block *)
876 		((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
877 
878 	/* sanity checking of raw super */
879 	if (sanity_check_raw_super(sb, *raw_super)) {
880 		brelse(*raw_super_buf);
881 		f2fs_msg(sb, KERN_ERR,
882 			"Can't find valid F2FS filesystem in %dth superblock",
883 								block + 1);
884 		if (block == 0) {
885 			block++;
886 			goto retry;
887 		} else {
888 			return -EINVAL;
889 		}
890 	}
891 
892 	return 0;
893 }
894 
895 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
896 {
897 	struct f2fs_sb_info *sbi;
898 	struct f2fs_super_block *raw_super;
899 	struct buffer_head *raw_super_buf;
900 	struct inode *root;
901 	long err = -EINVAL;
902 	int i;
903 
904 	/* allocate memory for f2fs-specific super block info */
905 	sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
906 	if (!sbi)
907 		return -ENOMEM;
908 
909 	/* set a block size */
910 	if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
911 		f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
912 		goto free_sbi;
913 	}
914 
915 	err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
916 	if (err)
917 		goto free_sbi;
918 
919 	sb->s_fs_info = sbi;
920 	/* init some FS parameters */
921 	sbi->active_logs = NR_CURSEG_TYPE;
922 
923 	set_opt(sbi, BG_GC);
924 
925 #ifdef CONFIG_F2FS_FS_XATTR
926 	set_opt(sbi, XATTR_USER);
927 #endif
928 #ifdef CONFIG_F2FS_FS_POSIX_ACL
929 	set_opt(sbi, POSIX_ACL);
930 #endif
931 	/* parse mount options */
932 	err = parse_options(sb, (char *)data);
933 	if (err)
934 		goto free_sb_buf;
935 
936 	sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
937 	sb->s_max_links = F2FS_LINK_MAX;
938 	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
939 
940 	sb->s_op = &f2fs_sops;
941 	sb->s_xattr = f2fs_xattr_handlers;
942 	sb->s_export_op = &f2fs_export_ops;
943 	sb->s_magic = F2FS_SUPER_MAGIC;
944 	sb->s_time_gran = 1;
945 	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
946 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
947 	memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
948 
949 	/* init f2fs-specific super block info */
950 	sbi->sb = sb;
951 	sbi->raw_super = raw_super;
952 	sbi->raw_super_buf = raw_super_buf;
953 	mutex_init(&sbi->gc_mutex);
954 	mutex_init(&sbi->writepages);
955 	mutex_init(&sbi->cp_mutex);
956 	init_rwsem(&sbi->node_write);
957 	sbi->por_doing = false;
958 	spin_lock_init(&sbi->stat_lock);
959 
960 	init_rwsem(&sbi->read_io.io_rwsem);
961 	sbi->read_io.sbi = sbi;
962 	sbi->read_io.bio = NULL;
963 	for (i = 0; i < NR_PAGE_TYPE; i++) {
964 		init_rwsem(&sbi->write_io[i].io_rwsem);
965 		sbi->write_io[i].sbi = sbi;
966 		sbi->write_io[i].bio = NULL;
967 	}
968 
969 	init_rwsem(&sbi->cp_rwsem);
970 	init_waitqueue_head(&sbi->cp_wait);
971 	init_sb_info(sbi);
972 
973 	/* get an inode for meta space */
974 	sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
975 	if (IS_ERR(sbi->meta_inode)) {
976 		f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
977 		err = PTR_ERR(sbi->meta_inode);
978 		goto free_sb_buf;
979 	}
980 
981 	err = get_valid_checkpoint(sbi);
982 	if (err) {
983 		f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
984 		goto free_meta_inode;
985 	}
986 
987 	/* sanity checking of checkpoint */
988 	err = -EINVAL;
989 	if (sanity_check_ckpt(sbi)) {
990 		f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
991 		goto free_cp;
992 	}
993 
994 	sbi->total_valid_node_count =
995 				le32_to_cpu(sbi->ckpt->valid_node_count);
996 	sbi->total_valid_inode_count =
997 				le32_to_cpu(sbi->ckpt->valid_inode_count);
998 	sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
999 	sbi->total_valid_block_count =
1000 				le64_to_cpu(sbi->ckpt->valid_block_count);
1001 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1002 	sbi->alloc_valid_block_count = 0;
1003 	INIT_LIST_HEAD(&sbi->dir_inode_list);
1004 	spin_lock_init(&sbi->dir_inode_lock);
1005 
1006 	init_ino_entry_info(sbi);
1007 
1008 	/* setup f2fs internal modules */
1009 	err = build_segment_manager(sbi);
1010 	if (err) {
1011 		f2fs_msg(sb, KERN_ERR,
1012 			"Failed to initialize F2FS segment manager");
1013 		goto free_sm;
1014 	}
1015 	err = build_node_manager(sbi);
1016 	if (err) {
1017 		f2fs_msg(sb, KERN_ERR,
1018 			"Failed to initialize F2FS node manager");
1019 		goto free_nm;
1020 	}
1021 
1022 	build_gc_manager(sbi);
1023 
1024 	/* get an inode for node space */
1025 	sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1026 	if (IS_ERR(sbi->node_inode)) {
1027 		f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1028 		err = PTR_ERR(sbi->node_inode);
1029 		goto free_nm;
1030 	}
1031 
1032 	/* if there are nt orphan nodes free them */
1033 	recover_orphan_inodes(sbi);
1034 
1035 	/* read root inode and dentry */
1036 	root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1037 	if (IS_ERR(root)) {
1038 		f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1039 		err = PTR_ERR(root);
1040 		goto free_node_inode;
1041 	}
1042 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1043 		iput(root);
1044 		err = -EINVAL;
1045 		goto free_node_inode;
1046 	}
1047 
1048 	sb->s_root = d_make_root(root); /* allocate root dentry */
1049 	if (!sb->s_root) {
1050 		err = -ENOMEM;
1051 		goto free_root_inode;
1052 	}
1053 
1054 	err = f2fs_build_stats(sbi);
1055 	if (err)
1056 		goto free_root_inode;
1057 
1058 	if (f2fs_proc_root)
1059 		sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1060 
1061 	if (sbi->s_proc)
1062 		proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1063 				 &f2fs_seq_segment_info_fops, sb);
1064 
1065 	if (test_opt(sbi, DISCARD)) {
1066 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1067 		if (!blk_queue_discard(q))
1068 			f2fs_msg(sb, KERN_WARNING,
1069 					"mounting with \"discard\" option, but "
1070 					"the device does not support discard");
1071 	}
1072 
1073 	sbi->s_kobj.kset = f2fs_kset;
1074 	init_completion(&sbi->s_kobj_unregister);
1075 	err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1076 							"%s", sb->s_id);
1077 	if (err)
1078 		goto free_proc;
1079 
1080 	/* recover fsynced data */
1081 	if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1082 		err = recover_fsync_data(sbi);
1083 		if (err)
1084 			f2fs_msg(sb, KERN_ERR,
1085 				"Cannot recover all fsync data errno=%ld", err);
1086 	}
1087 
1088 	/*
1089 	 * If filesystem is not mounted as read-only then
1090 	 * do start the gc_thread.
1091 	 */
1092 	if (!f2fs_readonly(sb)) {
1093 		/* After POR, we can run background GC thread.*/
1094 		err = start_gc_thread(sbi);
1095 		if (err)
1096 			goto free_kobj;
1097 	}
1098 	return 0;
1099 
1100 free_kobj:
1101 	kobject_del(&sbi->s_kobj);
1102 free_proc:
1103 	if (sbi->s_proc) {
1104 		remove_proc_entry("segment_info", sbi->s_proc);
1105 		remove_proc_entry(sb->s_id, f2fs_proc_root);
1106 	}
1107 	f2fs_destroy_stats(sbi);
1108 free_root_inode:
1109 	dput(sb->s_root);
1110 	sb->s_root = NULL;
1111 free_node_inode:
1112 	iput(sbi->node_inode);
1113 free_nm:
1114 	destroy_node_manager(sbi);
1115 free_sm:
1116 	destroy_segment_manager(sbi);
1117 free_cp:
1118 	kfree(sbi->ckpt);
1119 free_meta_inode:
1120 	make_bad_inode(sbi->meta_inode);
1121 	iput(sbi->meta_inode);
1122 free_sb_buf:
1123 	brelse(raw_super_buf);
1124 free_sbi:
1125 	kfree(sbi);
1126 	return err;
1127 }
1128 
1129 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1130 			const char *dev_name, void *data)
1131 {
1132 	return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1133 }
1134 
1135 static struct file_system_type f2fs_fs_type = {
1136 	.owner		= THIS_MODULE,
1137 	.name		= "f2fs",
1138 	.mount		= f2fs_mount,
1139 	.kill_sb	= kill_block_super,
1140 	.fs_flags	= FS_REQUIRES_DEV,
1141 };
1142 MODULE_ALIAS_FS("f2fs");
1143 
1144 static int __init init_inodecache(void)
1145 {
1146 	f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1147 			sizeof(struct f2fs_inode_info));
1148 	if (!f2fs_inode_cachep)
1149 		return -ENOMEM;
1150 	return 0;
1151 }
1152 
1153 static void destroy_inodecache(void)
1154 {
1155 	/*
1156 	 * Make sure all delayed rcu free inodes are flushed before we
1157 	 * destroy cache.
1158 	 */
1159 	rcu_barrier();
1160 	kmem_cache_destroy(f2fs_inode_cachep);
1161 }
1162 
1163 static int __init init_f2fs_fs(void)
1164 {
1165 	int err;
1166 
1167 	err = init_inodecache();
1168 	if (err)
1169 		goto fail;
1170 	err = create_node_manager_caches();
1171 	if (err)
1172 		goto free_inodecache;
1173 	err = create_segment_manager_caches();
1174 	if (err)
1175 		goto free_node_manager_caches;
1176 	err = create_gc_caches();
1177 	if (err)
1178 		goto free_segment_manager_caches;
1179 	err = create_checkpoint_caches();
1180 	if (err)
1181 		goto free_gc_caches;
1182 	f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1183 	if (!f2fs_kset) {
1184 		err = -ENOMEM;
1185 		goto free_checkpoint_caches;
1186 	}
1187 	err = register_filesystem(&f2fs_fs_type);
1188 	if (err)
1189 		goto free_kset;
1190 	f2fs_create_root_stats();
1191 	f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1192 	return 0;
1193 
1194 free_kset:
1195 	kset_unregister(f2fs_kset);
1196 free_checkpoint_caches:
1197 	destroy_checkpoint_caches();
1198 free_gc_caches:
1199 	destroy_gc_caches();
1200 free_segment_manager_caches:
1201 	destroy_segment_manager_caches();
1202 free_node_manager_caches:
1203 	destroy_node_manager_caches();
1204 free_inodecache:
1205 	destroy_inodecache();
1206 fail:
1207 	return err;
1208 }
1209 
1210 static void __exit exit_f2fs_fs(void)
1211 {
1212 	remove_proc_entry("fs/f2fs", NULL);
1213 	f2fs_destroy_root_stats();
1214 	unregister_filesystem(&f2fs_fs_type);
1215 	destroy_checkpoint_caches();
1216 	destroy_gc_caches();
1217 	destroy_segment_manager_caches();
1218 	destroy_node_manager_caches();
1219 	destroy_inodecache();
1220 	kset_unregister(f2fs_kset);
1221 }
1222 
1223 module_init(init_f2fs_fs)
1224 module_exit(exit_f2fs_fs)
1225 
1226 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1227 MODULE_DESCRIPTION("Flash Friendly File System");
1228 MODULE_LICENSE("GPL");
1229