xref: /openbmc/linux/fs/ext4/super.c (revision 64288aa9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ext4/super.c
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/fs/minix/inode.c
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  *
16  *  Big-endian to little-endian byte-swapping/bitmaps by
17  *        David S. Miller (davem@caip.rutgers.edu), 1995
18  */
19 
20 #include <linux/module.h>
21 #include <linux/string.h>
22 #include <linux/fs.h>
23 #include <linux/time.h>
24 #include <linux/vmalloc.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/backing-dev.h>
29 #include <linux/parser.h>
30 #include <linux/buffer_head.h>
31 #include <linux/exportfs.h>
32 #include <linux/vfs.h>
33 #include <linux/random.h>
34 #include <linux/mount.h>
35 #include <linux/namei.h>
36 #include <linux/quotaops.h>
37 #include <linux/seq_file.h>
38 #include <linux/ctype.h>
39 #include <linux/log2.h>
40 #include <linux/crc16.h>
41 #include <linux/dax.h>
42 #include <linux/uaccess.h>
43 #include <linux/iversion.h>
44 #include <linux/unicode.h>
45 #include <linux/part_stat.h>
46 #include <linux/kthread.h>
47 #include <linux/freezer.h>
48 #include <linux/fsnotify.h>
49 #include <linux/fs_context.h>
50 #include <linux/fs_parser.h>
51 
52 #include "ext4.h"
53 #include "ext4_extents.h"	/* Needed for trace points definition */
54 #include "ext4_jbd2.h"
55 #include "xattr.h"
56 #include "acl.h"
57 #include "mballoc.h"
58 #include "fsmap.h"
59 
60 #define CREATE_TRACE_POINTS
61 #include <trace/events/ext4.h>
62 
63 static struct ext4_lazy_init *ext4_li_info;
64 static DEFINE_MUTEX(ext4_li_mtx);
65 static struct ratelimit_state ext4_mount_msg_ratelimit;
66 
67 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
68 			     unsigned long journal_devnum);
69 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
70 static void ext4_update_super(struct super_block *sb);
71 static int ext4_commit_super(struct super_block *sb);
72 static int ext4_mark_recovery_complete(struct super_block *sb,
73 					struct ext4_super_block *es);
74 static int ext4_clear_journal_err(struct super_block *sb,
75 				  struct ext4_super_block *es);
76 static int ext4_sync_fs(struct super_block *sb, int wait);
77 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
78 static int ext4_unfreeze(struct super_block *sb);
79 static int ext4_freeze(struct super_block *sb);
80 static inline int ext2_feature_set_ok(struct super_block *sb);
81 static inline int ext3_feature_set_ok(struct super_block *sb);
82 static void ext4_destroy_lazyinit_thread(void);
83 static void ext4_unregister_li_request(struct super_block *sb);
84 static void ext4_clear_request_list(void);
85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
86 					    unsigned int journal_inum);
87 static int ext4_validate_options(struct fs_context *fc);
88 static int ext4_check_opt_consistency(struct fs_context *fc,
89 				      struct super_block *sb);
90 static int ext4_apply_options(struct fs_context *fc, struct super_block *sb);
91 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
92 static int ext4_get_tree(struct fs_context *fc);
93 static int ext4_reconfigure(struct fs_context *fc);
94 static void ext4_fc_free(struct fs_context *fc);
95 static int ext4_init_fs_context(struct fs_context *fc);
96 static const struct fs_parameter_spec ext4_param_specs[];
97 
98 /*
99  * Lock ordering
100  *
101  * page fault path:
102  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
103  *   -> page lock -> i_data_sem (rw)
104  *
105  * buffered write path:
106  * sb_start_write -> i_mutex -> mmap_lock
107  * sb_start_write -> i_mutex -> transaction start -> page lock ->
108  *   i_data_sem (rw)
109  *
110  * truncate:
111  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
112  *   page lock
113  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
114  *   i_data_sem (rw)
115  *
116  * direct IO:
117  * sb_start_write -> i_mutex -> mmap_lock
118  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
119  *
120  * writepages:
121  * transaction start -> page lock(s) -> i_data_sem (rw)
122  */
123 
124 static const struct fs_context_operations ext4_context_ops = {
125 	.parse_param	= ext4_parse_param,
126 	.get_tree	= ext4_get_tree,
127 	.reconfigure	= ext4_reconfigure,
128 	.free		= ext4_fc_free,
129 };
130 
131 
132 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
133 static struct file_system_type ext2_fs_type = {
134 	.owner			= THIS_MODULE,
135 	.name			= "ext2",
136 	.init_fs_context	= ext4_init_fs_context,
137 	.parameters		= ext4_param_specs,
138 	.kill_sb		= kill_block_super,
139 	.fs_flags		= FS_REQUIRES_DEV,
140 };
141 MODULE_ALIAS_FS("ext2");
142 MODULE_ALIAS("ext2");
143 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
144 #else
145 #define IS_EXT2_SB(sb) (0)
146 #endif
147 
148 
149 static struct file_system_type ext3_fs_type = {
150 	.owner			= THIS_MODULE,
151 	.name			= "ext3",
152 	.init_fs_context	= ext4_init_fs_context,
153 	.parameters		= ext4_param_specs,
154 	.kill_sb		= kill_block_super,
155 	.fs_flags		= FS_REQUIRES_DEV,
156 };
157 MODULE_ALIAS_FS("ext3");
158 MODULE_ALIAS("ext3");
159 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
160 
161 
162 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
163 				  bh_end_io_t *end_io)
164 {
165 	/*
166 	 * buffer's verified bit is no longer valid after reading from
167 	 * disk again due to write out error, clear it to make sure we
168 	 * recheck the buffer contents.
169 	 */
170 	clear_buffer_verified(bh);
171 
172 	bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
173 	get_bh(bh);
174 	submit_bh(REQ_OP_READ, op_flags, bh);
175 }
176 
177 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
178 			 bh_end_io_t *end_io)
179 {
180 	BUG_ON(!buffer_locked(bh));
181 
182 	if (ext4_buffer_uptodate(bh)) {
183 		unlock_buffer(bh);
184 		return;
185 	}
186 	__ext4_read_bh(bh, op_flags, end_io);
187 }
188 
189 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
190 {
191 	BUG_ON(!buffer_locked(bh));
192 
193 	if (ext4_buffer_uptodate(bh)) {
194 		unlock_buffer(bh);
195 		return 0;
196 	}
197 
198 	__ext4_read_bh(bh, op_flags, end_io);
199 
200 	wait_on_buffer(bh);
201 	if (buffer_uptodate(bh))
202 		return 0;
203 	return -EIO;
204 }
205 
206 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
207 {
208 	if (trylock_buffer(bh)) {
209 		if (wait)
210 			return ext4_read_bh(bh, op_flags, NULL);
211 		ext4_read_bh_nowait(bh, op_flags, NULL);
212 		return 0;
213 	}
214 	if (wait) {
215 		wait_on_buffer(bh);
216 		if (buffer_uptodate(bh))
217 			return 0;
218 		return -EIO;
219 	}
220 	return 0;
221 }
222 
223 /*
224  * This works like __bread_gfp() except it uses ERR_PTR for error
225  * returns.  Currently with sb_bread it's impossible to distinguish
226  * between ENOMEM and EIO situations (since both result in a NULL
227  * return.
228  */
229 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
230 					       sector_t block, int op_flags,
231 					       gfp_t gfp)
232 {
233 	struct buffer_head *bh;
234 	int ret;
235 
236 	bh = sb_getblk_gfp(sb, block, gfp);
237 	if (bh == NULL)
238 		return ERR_PTR(-ENOMEM);
239 	if (ext4_buffer_uptodate(bh))
240 		return bh;
241 
242 	ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
243 	if (ret) {
244 		put_bh(bh);
245 		return ERR_PTR(ret);
246 	}
247 	return bh;
248 }
249 
250 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
251 				   int op_flags)
252 {
253 	return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
254 }
255 
256 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
257 					    sector_t block)
258 {
259 	return __ext4_sb_bread_gfp(sb, block, 0, 0);
260 }
261 
262 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
263 {
264 	struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
265 
266 	if (likely(bh)) {
267 		ext4_read_bh_lock(bh, REQ_RAHEAD, false);
268 		brelse(bh);
269 	}
270 }
271 
272 static int ext4_verify_csum_type(struct super_block *sb,
273 				 struct ext4_super_block *es)
274 {
275 	if (!ext4_has_feature_metadata_csum(sb))
276 		return 1;
277 
278 	return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
279 }
280 
281 __le32 ext4_superblock_csum(struct super_block *sb,
282 			    struct ext4_super_block *es)
283 {
284 	struct ext4_sb_info *sbi = EXT4_SB(sb);
285 	int offset = offsetof(struct ext4_super_block, s_checksum);
286 	__u32 csum;
287 
288 	csum = ext4_chksum(sbi, ~0, (char *)es, offset);
289 
290 	return cpu_to_le32(csum);
291 }
292 
293 static int ext4_superblock_csum_verify(struct super_block *sb,
294 				       struct ext4_super_block *es)
295 {
296 	if (!ext4_has_metadata_csum(sb))
297 		return 1;
298 
299 	return es->s_checksum == ext4_superblock_csum(sb, es);
300 }
301 
302 void ext4_superblock_csum_set(struct super_block *sb)
303 {
304 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
305 
306 	if (!ext4_has_metadata_csum(sb))
307 		return;
308 
309 	es->s_checksum = ext4_superblock_csum(sb, es);
310 }
311 
312 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
313 			       struct ext4_group_desc *bg)
314 {
315 	return le32_to_cpu(bg->bg_block_bitmap_lo) |
316 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
317 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
318 }
319 
320 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
321 			       struct ext4_group_desc *bg)
322 {
323 	return le32_to_cpu(bg->bg_inode_bitmap_lo) |
324 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
325 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
326 }
327 
328 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
329 			      struct ext4_group_desc *bg)
330 {
331 	return le32_to_cpu(bg->bg_inode_table_lo) |
332 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
333 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
334 }
335 
336 __u32 ext4_free_group_clusters(struct super_block *sb,
337 			       struct ext4_group_desc *bg)
338 {
339 	return le16_to_cpu(bg->bg_free_blocks_count_lo) |
340 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
341 		 (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
342 }
343 
344 __u32 ext4_free_inodes_count(struct super_block *sb,
345 			      struct ext4_group_desc *bg)
346 {
347 	return le16_to_cpu(bg->bg_free_inodes_count_lo) |
348 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
349 		 (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
350 }
351 
352 __u32 ext4_used_dirs_count(struct super_block *sb,
353 			      struct ext4_group_desc *bg)
354 {
355 	return le16_to_cpu(bg->bg_used_dirs_count_lo) |
356 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
357 		 (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
358 }
359 
360 __u32 ext4_itable_unused_count(struct super_block *sb,
361 			      struct ext4_group_desc *bg)
362 {
363 	return le16_to_cpu(bg->bg_itable_unused_lo) |
364 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
365 		 (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
366 }
367 
368 void ext4_block_bitmap_set(struct super_block *sb,
369 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
370 {
371 	bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
372 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
373 		bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
374 }
375 
376 void ext4_inode_bitmap_set(struct super_block *sb,
377 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
378 {
379 	bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
380 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
381 		bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
382 }
383 
384 void ext4_inode_table_set(struct super_block *sb,
385 			  struct ext4_group_desc *bg, ext4_fsblk_t blk)
386 {
387 	bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
388 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
389 		bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
390 }
391 
392 void ext4_free_group_clusters_set(struct super_block *sb,
393 				  struct ext4_group_desc *bg, __u32 count)
394 {
395 	bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
396 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
397 		bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
398 }
399 
400 void ext4_free_inodes_set(struct super_block *sb,
401 			  struct ext4_group_desc *bg, __u32 count)
402 {
403 	bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
404 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
405 		bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
406 }
407 
408 void ext4_used_dirs_set(struct super_block *sb,
409 			  struct ext4_group_desc *bg, __u32 count)
410 {
411 	bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
412 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
413 		bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
414 }
415 
416 void ext4_itable_unused_set(struct super_block *sb,
417 			  struct ext4_group_desc *bg, __u32 count)
418 {
419 	bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
420 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
421 		bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
422 }
423 
424 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
425 {
426 	now = clamp_val(now, 0, (1ull << 40) - 1);
427 
428 	*lo = cpu_to_le32(lower_32_bits(now));
429 	*hi = upper_32_bits(now);
430 }
431 
432 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
433 {
434 	return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
435 }
436 #define ext4_update_tstamp(es, tstamp) \
437 	__ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
438 			     ktime_get_real_seconds())
439 #define ext4_get_tstamp(es, tstamp) \
440 	__ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
441 
442 /*
443  * The del_gendisk() function uninitializes the disk-specific data
444  * structures, including the bdi structure, without telling anyone
445  * else.  Once this happens, any attempt to call mark_buffer_dirty()
446  * (for example, by ext4_commit_super), will cause a kernel OOPS.
447  * This is a kludge to prevent these oops until we can put in a proper
448  * hook in del_gendisk() to inform the VFS and file system layers.
449  */
450 static int block_device_ejected(struct super_block *sb)
451 {
452 	struct inode *bd_inode = sb->s_bdev->bd_inode;
453 	struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
454 
455 	return bdi->dev == NULL;
456 }
457 
458 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
459 {
460 	struct super_block		*sb = journal->j_private;
461 	struct ext4_sb_info		*sbi = EXT4_SB(sb);
462 	int				error = is_journal_aborted(journal);
463 	struct ext4_journal_cb_entry	*jce;
464 
465 	BUG_ON(txn->t_state == T_FINISHED);
466 
467 	ext4_process_freed_data(sb, txn->t_tid);
468 
469 	spin_lock(&sbi->s_md_lock);
470 	while (!list_empty(&txn->t_private_list)) {
471 		jce = list_entry(txn->t_private_list.next,
472 				 struct ext4_journal_cb_entry, jce_list);
473 		list_del_init(&jce->jce_list);
474 		spin_unlock(&sbi->s_md_lock);
475 		jce->jce_func(sb, jce, error);
476 		spin_lock(&sbi->s_md_lock);
477 	}
478 	spin_unlock(&sbi->s_md_lock);
479 }
480 
481 /*
482  * This writepage callback for write_cache_pages()
483  * takes care of a few cases after page cleaning.
484  *
485  * write_cache_pages() already checks for dirty pages
486  * and calls clear_page_dirty_for_io(), which we want,
487  * to write protect the pages.
488  *
489  * However, we may have to redirty a page (see below.)
490  */
491 static int ext4_journalled_writepage_callback(struct page *page,
492 					      struct writeback_control *wbc,
493 					      void *data)
494 {
495 	transaction_t *transaction = (transaction_t *) data;
496 	struct buffer_head *bh, *head;
497 	struct journal_head *jh;
498 
499 	bh = head = page_buffers(page);
500 	do {
501 		/*
502 		 * We have to redirty a page in these cases:
503 		 * 1) If buffer is dirty, it means the page was dirty because it
504 		 * contains a buffer that needs checkpointing. So the dirty bit
505 		 * needs to be preserved so that checkpointing writes the buffer
506 		 * properly.
507 		 * 2) If buffer is not part of the committing transaction
508 		 * (we may have just accidentally come across this buffer because
509 		 * inode range tracking is not exact) or if the currently running
510 		 * transaction already contains this buffer as well, dirty bit
511 		 * needs to be preserved so that the buffer gets writeprotected
512 		 * properly on running transaction's commit.
513 		 */
514 		jh = bh2jh(bh);
515 		if (buffer_dirty(bh) ||
516 		    (jh && (jh->b_transaction != transaction ||
517 			    jh->b_next_transaction))) {
518 			redirty_page_for_writepage(wbc, page);
519 			goto out;
520 		}
521 	} while ((bh = bh->b_this_page) != head);
522 
523 out:
524 	return AOP_WRITEPAGE_ACTIVATE;
525 }
526 
527 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
528 {
529 	struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
530 	struct writeback_control wbc = {
531 		.sync_mode =  WB_SYNC_ALL,
532 		.nr_to_write = LONG_MAX,
533 		.range_start = jinode->i_dirty_start,
534 		.range_end = jinode->i_dirty_end,
535         };
536 
537 	return write_cache_pages(mapping, &wbc,
538 				 ext4_journalled_writepage_callback,
539 				 jinode->i_transaction);
540 }
541 
542 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
543 {
544 	int ret;
545 
546 	if (ext4_should_journal_data(jinode->i_vfs_inode))
547 		ret = ext4_journalled_submit_inode_data_buffers(jinode);
548 	else
549 		ret = jbd2_journal_submit_inode_data_buffers(jinode);
550 
551 	return ret;
552 }
553 
554 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
555 {
556 	int ret = 0;
557 
558 	if (!ext4_should_journal_data(jinode->i_vfs_inode))
559 		ret = jbd2_journal_finish_inode_data_buffers(jinode);
560 
561 	return ret;
562 }
563 
564 static bool system_going_down(void)
565 {
566 	return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
567 		|| system_state == SYSTEM_RESTART;
568 }
569 
570 struct ext4_err_translation {
571 	int code;
572 	int errno;
573 };
574 
575 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
576 
577 static struct ext4_err_translation err_translation[] = {
578 	EXT4_ERR_TRANSLATE(EIO),
579 	EXT4_ERR_TRANSLATE(ENOMEM),
580 	EXT4_ERR_TRANSLATE(EFSBADCRC),
581 	EXT4_ERR_TRANSLATE(EFSCORRUPTED),
582 	EXT4_ERR_TRANSLATE(ENOSPC),
583 	EXT4_ERR_TRANSLATE(ENOKEY),
584 	EXT4_ERR_TRANSLATE(EROFS),
585 	EXT4_ERR_TRANSLATE(EFBIG),
586 	EXT4_ERR_TRANSLATE(EEXIST),
587 	EXT4_ERR_TRANSLATE(ERANGE),
588 	EXT4_ERR_TRANSLATE(EOVERFLOW),
589 	EXT4_ERR_TRANSLATE(EBUSY),
590 	EXT4_ERR_TRANSLATE(ENOTDIR),
591 	EXT4_ERR_TRANSLATE(ENOTEMPTY),
592 	EXT4_ERR_TRANSLATE(ESHUTDOWN),
593 	EXT4_ERR_TRANSLATE(EFAULT),
594 };
595 
596 static int ext4_errno_to_code(int errno)
597 {
598 	int i;
599 
600 	for (i = 0; i < ARRAY_SIZE(err_translation); i++)
601 		if (err_translation[i].errno == errno)
602 			return err_translation[i].code;
603 	return EXT4_ERR_UNKNOWN;
604 }
605 
606 static void save_error_info(struct super_block *sb, int error,
607 			    __u32 ino, __u64 block,
608 			    const char *func, unsigned int line)
609 {
610 	struct ext4_sb_info *sbi = EXT4_SB(sb);
611 
612 	/* We default to EFSCORRUPTED error... */
613 	if (error == 0)
614 		error = EFSCORRUPTED;
615 
616 	spin_lock(&sbi->s_error_lock);
617 	sbi->s_add_error_count++;
618 	sbi->s_last_error_code = error;
619 	sbi->s_last_error_line = line;
620 	sbi->s_last_error_ino = ino;
621 	sbi->s_last_error_block = block;
622 	sbi->s_last_error_func = func;
623 	sbi->s_last_error_time = ktime_get_real_seconds();
624 	if (!sbi->s_first_error_time) {
625 		sbi->s_first_error_code = error;
626 		sbi->s_first_error_line = line;
627 		sbi->s_first_error_ino = ino;
628 		sbi->s_first_error_block = block;
629 		sbi->s_first_error_func = func;
630 		sbi->s_first_error_time = sbi->s_last_error_time;
631 	}
632 	spin_unlock(&sbi->s_error_lock);
633 }
634 
635 /* Deal with the reporting of failure conditions on a filesystem such as
636  * inconsistencies detected or read IO failures.
637  *
638  * On ext2, we can store the error state of the filesystem in the
639  * superblock.  That is not possible on ext4, because we may have other
640  * write ordering constraints on the superblock which prevent us from
641  * writing it out straight away; and given that the journal is about to
642  * be aborted, we can't rely on the current, or future, transactions to
643  * write out the superblock safely.
644  *
645  * We'll just use the jbd2_journal_abort() error code to record an error in
646  * the journal instead.  On recovery, the journal will complain about
647  * that error until we've noted it down and cleared it.
648  *
649  * If force_ro is set, we unconditionally force the filesystem into an
650  * ABORT|READONLY state, unless the error response on the fs has been set to
651  * panic in which case we take the easy way out and panic immediately. This is
652  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
653  * at a critical moment in log management.
654  */
655 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
656 			      __u32 ino, __u64 block,
657 			      const char *func, unsigned int line)
658 {
659 	journal_t *journal = EXT4_SB(sb)->s_journal;
660 	bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
661 
662 	EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
663 	if (test_opt(sb, WARN_ON_ERROR))
664 		WARN_ON_ONCE(1);
665 
666 	if (!continue_fs && !sb_rdonly(sb)) {
667 		ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
668 		if (journal)
669 			jbd2_journal_abort(journal, -EIO);
670 	}
671 
672 	if (!bdev_read_only(sb->s_bdev)) {
673 		save_error_info(sb, error, ino, block, func, line);
674 		/*
675 		 * In case the fs should keep running, we need to writeout
676 		 * superblock through the journal. Due to lock ordering
677 		 * constraints, it may not be safe to do it right here so we
678 		 * defer superblock flushing to a workqueue.
679 		 */
680 		if (continue_fs && journal)
681 			schedule_work(&EXT4_SB(sb)->s_error_work);
682 		else
683 			ext4_commit_super(sb);
684 	}
685 
686 	/*
687 	 * We force ERRORS_RO behavior when system is rebooting. Otherwise we
688 	 * could panic during 'reboot -f' as the underlying device got already
689 	 * disabled.
690 	 */
691 	if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
692 		panic("EXT4-fs (device %s): panic forced after error\n",
693 			sb->s_id);
694 	}
695 
696 	if (sb_rdonly(sb) || continue_fs)
697 		return;
698 
699 	ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
700 	/*
701 	 * Make sure updated value of ->s_mount_flags will be visible before
702 	 * ->s_flags update
703 	 */
704 	smp_wmb();
705 	sb->s_flags |= SB_RDONLY;
706 }
707 
708 static void flush_stashed_error_work(struct work_struct *work)
709 {
710 	struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
711 						s_error_work);
712 	journal_t *journal = sbi->s_journal;
713 	handle_t *handle;
714 
715 	/*
716 	 * If the journal is still running, we have to write out superblock
717 	 * through the journal to avoid collisions of other journalled sb
718 	 * updates.
719 	 *
720 	 * We use directly jbd2 functions here to avoid recursing back into
721 	 * ext4 error handling code during handling of previous errors.
722 	 */
723 	if (!sb_rdonly(sbi->s_sb) && journal) {
724 		struct buffer_head *sbh = sbi->s_sbh;
725 		handle = jbd2_journal_start(journal, 1);
726 		if (IS_ERR(handle))
727 			goto write_directly;
728 		if (jbd2_journal_get_write_access(handle, sbh)) {
729 			jbd2_journal_stop(handle);
730 			goto write_directly;
731 		}
732 		ext4_update_super(sbi->s_sb);
733 		if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
734 			ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
735 				 "superblock detected");
736 			clear_buffer_write_io_error(sbh);
737 			set_buffer_uptodate(sbh);
738 		}
739 
740 		if (jbd2_journal_dirty_metadata(handle, sbh)) {
741 			jbd2_journal_stop(handle);
742 			goto write_directly;
743 		}
744 		jbd2_journal_stop(handle);
745 		ext4_notify_error_sysfs(sbi);
746 		return;
747 	}
748 write_directly:
749 	/*
750 	 * Write through journal failed. Write sb directly to get error info
751 	 * out and hope for the best.
752 	 */
753 	ext4_commit_super(sbi->s_sb);
754 	ext4_notify_error_sysfs(sbi);
755 }
756 
757 #define ext4_error_ratelimit(sb)					\
758 		___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),	\
759 			     "EXT4-fs error")
760 
761 void __ext4_error(struct super_block *sb, const char *function,
762 		  unsigned int line, bool force_ro, int error, __u64 block,
763 		  const char *fmt, ...)
764 {
765 	struct va_format vaf;
766 	va_list args;
767 
768 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
769 		return;
770 
771 	trace_ext4_error(sb, function, line);
772 	if (ext4_error_ratelimit(sb)) {
773 		va_start(args, fmt);
774 		vaf.fmt = fmt;
775 		vaf.va = &args;
776 		printk(KERN_CRIT
777 		       "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
778 		       sb->s_id, function, line, current->comm, &vaf);
779 		va_end(args);
780 	}
781 	fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
782 
783 	ext4_handle_error(sb, force_ro, error, 0, block, function, line);
784 }
785 
786 void __ext4_error_inode(struct inode *inode, const char *function,
787 			unsigned int line, ext4_fsblk_t block, int error,
788 			const char *fmt, ...)
789 {
790 	va_list args;
791 	struct va_format vaf;
792 
793 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
794 		return;
795 
796 	trace_ext4_error(inode->i_sb, function, line);
797 	if (ext4_error_ratelimit(inode->i_sb)) {
798 		va_start(args, fmt);
799 		vaf.fmt = fmt;
800 		vaf.va = &args;
801 		if (block)
802 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
803 			       "inode #%lu: block %llu: comm %s: %pV\n",
804 			       inode->i_sb->s_id, function, line, inode->i_ino,
805 			       block, current->comm, &vaf);
806 		else
807 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
808 			       "inode #%lu: comm %s: %pV\n",
809 			       inode->i_sb->s_id, function, line, inode->i_ino,
810 			       current->comm, &vaf);
811 		va_end(args);
812 	}
813 	fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
814 
815 	ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
816 			  function, line);
817 }
818 
819 void __ext4_error_file(struct file *file, const char *function,
820 		       unsigned int line, ext4_fsblk_t block,
821 		       const char *fmt, ...)
822 {
823 	va_list args;
824 	struct va_format vaf;
825 	struct inode *inode = file_inode(file);
826 	char pathname[80], *path;
827 
828 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
829 		return;
830 
831 	trace_ext4_error(inode->i_sb, function, line);
832 	if (ext4_error_ratelimit(inode->i_sb)) {
833 		path = file_path(file, pathname, sizeof(pathname));
834 		if (IS_ERR(path))
835 			path = "(unknown)";
836 		va_start(args, fmt);
837 		vaf.fmt = fmt;
838 		vaf.va = &args;
839 		if (block)
840 			printk(KERN_CRIT
841 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
842 			       "block %llu: comm %s: path %s: %pV\n",
843 			       inode->i_sb->s_id, function, line, inode->i_ino,
844 			       block, current->comm, path, &vaf);
845 		else
846 			printk(KERN_CRIT
847 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
848 			       "comm %s: path %s: %pV\n",
849 			       inode->i_sb->s_id, function, line, inode->i_ino,
850 			       current->comm, path, &vaf);
851 		va_end(args);
852 	}
853 	fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
854 
855 	ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
856 			  function, line);
857 }
858 
859 const char *ext4_decode_error(struct super_block *sb, int errno,
860 			      char nbuf[16])
861 {
862 	char *errstr = NULL;
863 
864 	switch (errno) {
865 	case -EFSCORRUPTED:
866 		errstr = "Corrupt filesystem";
867 		break;
868 	case -EFSBADCRC:
869 		errstr = "Filesystem failed CRC";
870 		break;
871 	case -EIO:
872 		errstr = "IO failure";
873 		break;
874 	case -ENOMEM:
875 		errstr = "Out of memory";
876 		break;
877 	case -EROFS:
878 		if (!sb || (EXT4_SB(sb)->s_journal &&
879 			    EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
880 			errstr = "Journal has aborted";
881 		else
882 			errstr = "Readonly filesystem";
883 		break;
884 	default:
885 		/* If the caller passed in an extra buffer for unknown
886 		 * errors, textualise them now.  Else we just return
887 		 * NULL. */
888 		if (nbuf) {
889 			/* Check for truncated error codes... */
890 			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
891 				errstr = nbuf;
892 		}
893 		break;
894 	}
895 
896 	return errstr;
897 }
898 
899 /* __ext4_std_error decodes expected errors from journaling functions
900  * automatically and invokes the appropriate error response.  */
901 
902 void __ext4_std_error(struct super_block *sb, const char *function,
903 		      unsigned int line, int errno)
904 {
905 	char nbuf[16];
906 	const char *errstr;
907 
908 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
909 		return;
910 
911 	/* Special case: if the error is EROFS, and we're not already
912 	 * inside a transaction, then there's really no point in logging
913 	 * an error. */
914 	if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
915 		return;
916 
917 	if (ext4_error_ratelimit(sb)) {
918 		errstr = ext4_decode_error(sb, errno, nbuf);
919 		printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
920 		       sb->s_id, function, line, errstr);
921 	}
922 	fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
923 
924 	ext4_handle_error(sb, false, -errno, 0, 0, function, line);
925 }
926 
927 void __ext4_msg(struct super_block *sb,
928 		const char *prefix, const char *fmt, ...)
929 {
930 	struct va_format vaf;
931 	va_list args;
932 
933 	if (sb) {
934 		atomic_inc(&EXT4_SB(sb)->s_msg_count);
935 		if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
936 				  "EXT4-fs"))
937 			return;
938 	}
939 
940 	va_start(args, fmt);
941 	vaf.fmt = fmt;
942 	vaf.va = &args;
943 	if (sb)
944 		printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
945 	else
946 		printk("%sEXT4-fs: %pV\n", prefix, &vaf);
947 	va_end(args);
948 }
949 
950 static int ext4_warning_ratelimit(struct super_block *sb)
951 {
952 	atomic_inc(&EXT4_SB(sb)->s_warning_count);
953 	return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
954 			    "EXT4-fs warning");
955 }
956 
957 void __ext4_warning(struct super_block *sb, const char *function,
958 		    unsigned int line, const char *fmt, ...)
959 {
960 	struct va_format vaf;
961 	va_list args;
962 
963 	if (!ext4_warning_ratelimit(sb))
964 		return;
965 
966 	va_start(args, fmt);
967 	vaf.fmt = fmt;
968 	vaf.va = &args;
969 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
970 	       sb->s_id, function, line, &vaf);
971 	va_end(args);
972 }
973 
974 void __ext4_warning_inode(const struct inode *inode, const char *function,
975 			  unsigned int line, const char *fmt, ...)
976 {
977 	struct va_format vaf;
978 	va_list args;
979 
980 	if (!ext4_warning_ratelimit(inode->i_sb))
981 		return;
982 
983 	va_start(args, fmt);
984 	vaf.fmt = fmt;
985 	vaf.va = &args;
986 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
987 	       "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
988 	       function, line, inode->i_ino, current->comm, &vaf);
989 	va_end(args);
990 }
991 
992 void __ext4_grp_locked_error(const char *function, unsigned int line,
993 			     struct super_block *sb, ext4_group_t grp,
994 			     unsigned long ino, ext4_fsblk_t block,
995 			     const char *fmt, ...)
996 __releases(bitlock)
997 __acquires(bitlock)
998 {
999 	struct va_format vaf;
1000 	va_list args;
1001 
1002 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
1003 		return;
1004 
1005 	trace_ext4_error(sb, function, line);
1006 	if (ext4_error_ratelimit(sb)) {
1007 		va_start(args, fmt);
1008 		vaf.fmt = fmt;
1009 		vaf.va = &args;
1010 		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1011 		       sb->s_id, function, line, grp);
1012 		if (ino)
1013 			printk(KERN_CONT "inode %lu: ", ino);
1014 		if (block)
1015 			printk(KERN_CONT "block %llu:",
1016 			       (unsigned long long) block);
1017 		printk(KERN_CONT "%pV\n", &vaf);
1018 		va_end(args);
1019 	}
1020 
1021 	if (test_opt(sb, ERRORS_CONT)) {
1022 		if (test_opt(sb, WARN_ON_ERROR))
1023 			WARN_ON_ONCE(1);
1024 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1025 		if (!bdev_read_only(sb->s_bdev)) {
1026 			save_error_info(sb, EFSCORRUPTED, ino, block, function,
1027 					line);
1028 			schedule_work(&EXT4_SB(sb)->s_error_work);
1029 		}
1030 		return;
1031 	}
1032 	ext4_unlock_group(sb, grp);
1033 	ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1034 	/*
1035 	 * We only get here in the ERRORS_RO case; relocking the group
1036 	 * may be dangerous, but nothing bad will happen since the
1037 	 * filesystem will have already been marked read/only and the
1038 	 * journal has been aborted.  We return 1 as a hint to callers
1039 	 * who might what to use the return value from
1040 	 * ext4_grp_locked_error() to distinguish between the
1041 	 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1042 	 * aggressively from the ext4 function in question, with a
1043 	 * more appropriate error code.
1044 	 */
1045 	ext4_lock_group(sb, grp);
1046 	return;
1047 }
1048 
1049 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1050 				     ext4_group_t group,
1051 				     unsigned int flags)
1052 {
1053 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1054 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1055 	struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1056 	int ret;
1057 
1058 	if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1059 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1060 					    &grp->bb_state);
1061 		if (!ret)
1062 			percpu_counter_sub(&sbi->s_freeclusters_counter,
1063 					   grp->bb_free);
1064 	}
1065 
1066 	if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1067 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1068 					    &grp->bb_state);
1069 		if (!ret && gdp) {
1070 			int count;
1071 
1072 			count = ext4_free_inodes_count(sb, gdp);
1073 			percpu_counter_sub(&sbi->s_freeinodes_counter,
1074 					   count);
1075 		}
1076 	}
1077 }
1078 
1079 void ext4_update_dynamic_rev(struct super_block *sb)
1080 {
1081 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1082 
1083 	if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1084 		return;
1085 
1086 	ext4_warning(sb,
1087 		     "updating to rev %d because of new feature flag, "
1088 		     "running e2fsck is recommended",
1089 		     EXT4_DYNAMIC_REV);
1090 
1091 	es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1092 	es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1093 	es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1094 	/* leave es->s_feature_*compat flags alone */
1095 	/* es->s_uuid will be set by e2fsck if empty */
1096 
1097 	/*
1098 	 * The rest of the superblock fields should be zero, and if not it
1099 	 * means they are likely already in use, so leave them alone.  We
1100 	 * can leave it up to e2fsck to clean up any inconsistencies there.
1101 	 */
1102 }
1103 
1104 /*
1105  * Open the external journal device
1106  */
1107 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1108 {
1109 	struct block_device *bdev;
1110 
1111 	bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1112 	if (IS_ERR(bdev))
1113 		goto fail;
1114 	return bdev;
1115 
1116 fail:
1117 	ext4_msg(sb, KERN_ERR,
1118 		 "failed to open journal device unknown-block(%u,%u) %ld",
1119 		 MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1120 	return NULL;
1121 }
1122 
1123 /*
1124  * Release the journal device
1125  */
1126 static void ext4_blkdev_put(struct block_device *bdev)
1127 {
1128 	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1129 }
1130 
1131 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1132 {
1133 	struct block_device *bdev;
1134 	bdev = sbi->s_journal_bdev;
1135 	if (bdev) {
1136 		ext4_blkdev_put(bdev);
1137 		sbi->s_journal_bdev = NULL;
1138 	}
1139 }
1140 
1141 static inline struct inode *orphan_list_entry(struct list_head *l)
1142 {
1143 	return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1144 }
1145 
1146 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1147 {
1148 	struct list_head *l;
1149 
1150 	ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1151 		 le32_to_cpu(sbi->s_es->s_last_orphan));
1152 
1153 	printk(KERN_ERR "sb_info orphan list:\n");
1154 	list_for_each(l, &sbi->s_orphan) {
1155 		struct inode *inode = orphan_list_entry(l);
1156 		printk(KERN_ERR "  "
1157 		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1158 		       inode->i_sb->s_id, inode->i_ino, inode,
1159 		       inode->i_mode, inode->i_nlink,
1160 		       NEXT_ORPHAN(inode));
1161 	}
1162 }
1163 
1164 #ifdef CONFIG_QUOTA
1165 static int ext4_quota_off(struct super_block *sb, int type);
1166 
1167 static inline void ext4_quota_off_umount(struct super_block *sb)
1168 {
1169 	int type;
1170 
1171 	/* Use our quota_off function to clear inode flags etc. */
1172 	for (type = 0; type < EXT4_MAXQUOTAS; type++)
1173 		ext4_quota_off(sb, type);
1174 }
1175 
1176 /*
1177  * This is a helper function which is used in the mount/remount
1178  * codepaths (which holds s_umount) to fetch the quota file name.
1179  */
1180 static inline char *get_qf_name(struct super_block *sb,
1181 				struct ext4_sb_info *sbi,
1182 				int type)
1183 {
1184 	return rcu_dereference_protected(sbi->s_qf_names[type],
1185 					 lockdep_is_held(&sb->s_umount));
1186 }
1187 #else
1188 static inline void ext4_quota_off_umount(struct super_block *sb)
1189 {
1190 }
1191 #endif
1192 
1193 static void ext4_put_super(struct super_block *sb)
1194 {
1195 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1196 	struct ext4_super_block *es = sbi->s_es;
1197 	struct buffer_head **group_desc;
1198 	struct flex_groups **flex_groups;
1199 	int aborted = 0;
1200 	int i, err;
1201 
1202 	ext4_unregister_li_request(sb);
1203 	ext4_quota_off_umount(sb);
1204 
1205 	flush_work(&sbi->s_error_work);
1206 	destroy_workqueue(sbi->rsv_conversion_wq);
1207 	ext4_release_orphan_info(sb);
1208 
1209 	/*
1210 	 * Unregister sysfs before destroying jbd2 journal.
1211 	 * Since we could still access attr_journal_task attribute via sysfs
1212 	 * path which could have sbi->s_journal->j_task as NULL
1213 	 */
1214 	ext4_unregister_sysfs(sb);
1215 
1216 	if (sbi->s_journal) {
1217 		aborted = is_journal_aborted(sbi->s_journal);
1218 		err = jbd2_journal_destroy(sbi->s_journal);
1219 		sbi->s_journal = NULL;
1220 		if ((err < 0) && !aborted) {
1221 			ext4_abort(sb, -err, "Couldn't clean up the journal");
1222 		}
1223 	}
1224 
1225 	ext4_es_unregister_shrinker(sbi);
1226 	del_timer_sync(&sbi->s_err_report);
1227 	ext4_release_system_zone(sb);
1228 	ext4_mb_release(sb);
1229 	ext4_ext_release(sb);
1230 
1231 	if (!sb_rdonly(sb) && !aborted) {
1232 		ext4_clear_feature_journal_needs_recovery(sb);
1233 		ext4_clear_feature_orphan_present(sb);
1234 		es->s_state = cpu_to_le16(sbi->s_mount_state);
1235 	}
1236 	if (!sb_rdonly(sb))
1237 		ext4_commit_super(sb);
1238 
1239 	rcu_read_lock();
1240 	group_desc = rcu_dereference(sbi->s_group_desc);
1241 	for (i = 0; i < sbi->s_gdb_count; i++)
1242 		brelse(group_desc[i]);
1243 	kvfree(group_desc);
1244 	flex_groups = rcu_dereference(sbi->s_flex_groups);
1245 	if (flex_groups) {
1246 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1247 			kvfree(flex_groups[i]);
1248 		kvfree(flex_groups);
1249 	}
1250 	rcu_read_unlock();
1251 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
1252 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
1253 	percpu_counter_destroy(&sbi->s_dirs_counter);
1254 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1255 	percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1256 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
1257 #ifdef CONFIG_QUOTA
1258 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
1259 		kfree(get_qf_name(sb, sbi, i));
1260 #endif
1261 
1262 	/* Debugging code just in case the in-memory inode orphan list
1263 	 * isn't empty.  The on-disk one can be non-empty if we've
1264 	 * detected an error and taken the fs readonly, but the
1265 	 * in-memory list had better be clean by this point. */
1266 	if (!list_empty(&sbi->s_orphan))
1267 		dump_orphan_list(sb, sbi);
1268 	ASSERT(list_empty(&sbi->s_orphan));
1269 
1270 	sync_blockdev(sb->s_bdev);
1271 	invalidate_bdev(sb->s_bdev);
1272 	if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1273 		/*
1274 		 * Invalidate the journal device's buffers.  We don't want them
1275 		 * floating about in memory - the physical journal device may
1276 		 * hotswapped, and it breaks the `ro-after' testing code.
1277 		 */
1278 		sync_blockdev(sbi->s_journal_bdev);
1279 		invalidate_bdev(sbi->s_journal_bdev);
1280 		ext4_blkdev_remove(sbi);
1281 	}
1282 
1283 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1284 	sbi->s_ea_inode_cache = NULL;
1285 
1286 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1287 	sbi->s_ea_block_cache = NULL;
1288 
1289 	ext4_stop_mmpd(sbi);
1290 
1291 	brelse(sbi->s_sbh);
1292 	sb->s_fs_info = NULL;
1293 	/*
1294 	 * Now that we are completely done shutting down the
1295 	 * superblock, we need to actually destroy the kobject.
1296 	 */
1297 	kobject_put(&sbi->s_kobj);
1298 	wait_for_completion(&sbi->s_kobj_unregister);
1299 	if (sbi->s_chksum_driver)
1300 		crypto_free_shash(sbi->s_chksum_driver);
1301 	kfree(sbi->s_blockgroup_lock);
1302 	fs_put_dax(sbi->s_daxdev);
1303 	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1304 #ifdef CONFIG_UNICODE
1305 	utf8_unload(sb->s_encoding);
1306 #endif
1307 	kfree(sbi);
1308 }
1309 
1310 static struct kmem_cache *ext4_inode_cachep;
1311 
1312 /*
1313  * Called inside transaction, so use GFP_NOFS
1314  */
1315 static struct inode *ext4_alloc_inode(struct super_block *sb)
1316 {
1317 	struct ext4_inode_info *ei;
1318 
1319 	ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1320 	if (!ei)
1321 		return NULL;
1322 
1323 	inode_set_iversion(&ei->vfs_inode, 1);
1324 	spin_lock_init(&ei->i_raw_lock);
1325 	INIT_LIST_HEAD(&ei->i_prealloc_list);
1326 	atomic_set(&ei->i_prealloc_active, 0);
1327 	spin_lock_init(&ei->i_prealloc_lock);
1328 	ext4_es_init_tree(&ei->i_es_tree);
1329 	rwlock_init(&ei->i_es_lock);
1330 	INIT_LIST_HEAD(&ei->i_es_list);
1331 	ei->i_es_all_nr = 0;
1332 	ei->i_es_shk_nr = 0;
1333 	ei->i_es_shrink_lblk = 0;
1334 	ei->i_reserved_data_blocks = 0;
1335 	spin_lock_init(&(ei->i_block_reservation_lock));
1336 	ext4_init_pending_tree(&ei->i_pending_tree);
1337 #ifdef CONFIG_QUOTA
1338 	ei->i_reserved_quota = 0;
1339 	memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1340 #endif
1341 	ei->jinode = NULL;
1342 	INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1343 	spin_lock_init(&ei->i_completed_io_lock);
1344 	ei->i_sync_tid = 0;
1345 	ei->i_datasync_tid = 0;
1346 	atomic_set(&ei->i_unwritten, 0);
1347 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1348 	ext4_fc_init_inode(&ei->vfs_inode);
1349 	mutex_init(&ei->i_fc_lock);
1350 	return &ei->vfs_inode;
1351 }
1352 
1353 static int ext4_drop_inode(struct inode *inode)
1354 {
1355 	int drop = generic_drop_inode(inode);
1356 
1357 	if (!drop)
1358 		drop = fscrypt_drop_inode(inode);
1359 
1360 	trace_ext4_drop_inode(inode, drop);
1361 	return drop;
1362 }
1363 
1364 static void ext4_free_in_core_inode(struct inode *inode)
1365 {
1366 	fscrypt_free_inode(inode);
1367 	if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1368 		pr_warn("%s: inode %ld still in fc list",
1369 			__func__, inode->i_ino);
1370 	}
1371 	kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1372 }
1373 
1374 static void ext4_destroy_inode(struct inode *inode)
1375 {
1376 	if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1377 		ext4_msg(inode->i_sb, KERN_ERR,
1378 			 "Inode %lu (%p): orphan list check failed!",
1379 			 inode->i_ino, EXT4_I(inode));
1380 		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1381 				EXT4_I(inode), sizeof(struct ext4_inode_info),
1382 				true);
1383 		dump_stack();
1384 	}
1385 
1386 	if (EXT4_I(inode)->i_reserved_data_blocks)
1387 		ext4_msg(inode->i_sb, KERN_ERR,
1388 			 "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1389 			 inode->i_ino, EXT4_I(inode),
1390 			 EXT4_I(inode)->i_reserved_data_blocks);
1391 }
1392 
1393 static void init_once(void *foo)
1394 {
1395 	struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1396 
1397 	INIT_LIST_HEAD(&ei->i_orphan);
1398 	init_rwsem(&ei->xattr_sem);
1399 	init_rwsem(&ei->i_data_sem);
1400 	inode_init_once(&ei->vfs_inode);
1401 	ext4_fc_init_inode(&ei->vfs_inode);
1402 }
1403 
1404 static int __init init_inodecache(void)
1405 {
1406 	ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1407 				sizeof(struct ext4_inode_info), 0,
1408 				(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1409 					SLAB_ACCOUNT),
1410 				offsetof(struct ext4_inode_info, i_data),
1411 				sizeof_field(struct ext4_inode_info, i_data),
1412 				init_once);
1413 	if (ext4_inode_cachep == NULL)
1414 		return -ENOMEM;
1415 	return 0;
1416 }
1417 
1418 static void destroy_inodecache(void)
1419 {
1420 	/*
1421 	 * Make sure all delayed rcu free inodes are flushed before we
1422 	 * destroy cache.
1423 	 */
1424 	rcu_barrier();
1425 	kmem_cache_destroy(ext4_inode_cachep);
1426 }
1427 
1428 void ext4_clear_inode(struct inode *inode)
1429 {
1430 	ext4_fc_del(inode);
1431 	invalidate_inode_buffers(inode);
1432 	clear_inode(inode);
1433 	ext4_discard_preallocations(inode, 0);
1434 	ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1435 	dquot_drop(inode);
1436 	if (EXT4_I(inode)->jinode) {
1437 		jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1438 					       EXT4_I(inode)->jinode);
1439 		jbd2_free_inode(EXT4_I(inode)->jinode);
1440 		EXT4_I(inode)->jinode = NULL;
1441 	}
1442 	fscrypt_put_encryption_info(inode);
1443 	fsverity_cleanup_inode(inode);
1444 }
1445 
1446 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1447 					u64 ino, u32 generation)
1448 {
1449 	struct inode *inode;
1450 
1451 	/*
1452 	 * Currently we don't know the generation for parent directory, so
1453 	 * a generation of 0 means "accept any"
1454 	 */
1455 	inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1456 	if (IS_ERR(inode))
1457 		return ERR_CAST(inode);
1458 	if (generation && inode->i_generation != generation) {
1459 		iput(inode);
1460 		return ERR_PTR(-ESTALE);
1461 	}
1462 
1463 	return inode;
1464 }
1465 
1466 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1467 					int fh_len, int fh_type)
1468 {
1469 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1470 				    ext4_nfs_get_inode);
1471 }
1472 
1473 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1474 					int fh_len, int fh_type)
1475 {
1476 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1477 				    ext4_nfs_get_inode);
1478 }
1479 
1480 static int ext4_nfs_commit_metadata(struct inode *inode)
1481 {
1482 	struct writeback_control wbc = {
1483 		.sync_mode = WB_SYNC_ALL
1484 	};
1485 
1486 	trace_ext4_nfs_commit_metadata(inode);
1487 	return ext4_write_inode(inode, &wbc);
1488 }
1489 
1490 #ifdef CONFIG_FS_ENCRYPTION
1491 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1492 {
1493 	return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1494 				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1495 }
1496 
1497 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1498 							void *fs_data)
1499 {
1500 	handle_t *handle = fs_data;
1501 	int res, res2, credits, retries = 0;
1502 
1503 	/*
1504 	 * Encrypting the root directory is not allowed because e2fsck expects
1505 	 * lost+found to exist and be unencrypted, and encrypting the root
1506 	 * directory would imply encrypting the lost+found directory as well as
1507 	 * the filename "lost+found" itself.
1508 	 */
1509 	if (inode->i_ino == EXT4_ROOT_INO)
1510 		return -EPERM;
1511 
1512 	if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1513 		return -EINVAL;
1514 
1515 	if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1516 		return -EOPNOTSUPP;
1517 
1518 	res = ext4_convert_inline_data(inode);
1519 	if (res)
1520 		return res;
1521 
1522 	/*
1523 	 * If a journal handle was specified, then the encryption context is
1524 	 * being set on a new inode via inheritance and is part of a larger
1525 	 * transaction to create the inode.  Otherwise the encryption context is
1526 	 * being set on an existing inode in its own transaction.  Only in the
1527 	 * latter case should the "retry on ENOSPC" logic be used.
1528 	 */
1529 
1530 	if (handle) {
1531 		res = ext4_xattr_set_handle(handle, inode,
1532 					    EXT4_XATTR_INDEX_ENCRYPTION,
1533 					    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1534 					    ctx, len, 0);
1535 		if (!res) {
1536 			ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1537 			ext4_clear_inode_state(inode,
1538 					EXT4_STATE_MAY_INLINE_DATA);
1539 			/*
1540 			 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1541 			 * S_DAX may be disabled
1542 			 */
1543 			ext4_set_inode_flags(inode, false);
1544 		}
1545 		return res;
1546 	}
1547 
1548 	res = dquot_initialize(inode);
1549 	if (res)
1550 		return res;
1551 retry:
1552 	res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1553 				     &credits);
1554 	if (res)
1555 		return res;
1556 
1557 	handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1558 	if (IS_ERR(handle))
1559 		return PTR_ERR(handle);
1560 
1561 	res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1562 				    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1563 				    ctx, len, 0);
1564 	if (!res) {
1565 		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1566 		/*
1567 		 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1568 		 * S_DAX may be disabled
1569 		 */
1570 		ext4_set_inode_flags(inode, false);
1571 		res = ext4_mark_inode_dirty(handle, inode);
1572 		if (res)
1573 			EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1574 	}
1575 	res2 = ext4_journal_stop(handle);
1576 
1577 	if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1578 		goto retry;
1579 	if (!res)
1580 		res = res2;
1581 	return res;
1582 }
1583 
1584 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1585 {
1586 	return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1587 }
1588 
1589 static bool ext4_has_stable_inodes(struct super_block *sb)
1590 {
1591 	return ext4_has_feature_stable_inodes(sb);
1592 }
1593 
1594 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1595 				       int *ino_bits_ret, int *lblk_bits_ret)
1596 {
1597 	*ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1598 	*lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1599 }
1600 
1601 static const struct fscrypt_operations ext4_cryptops = {
1602 	.key_prefix		= "ext4:",
1603 	.get_context		= ext4_get_context,
1604 	.set_context		= ext4_set_context,
1605 	.get_dummy_policy	= ext4_get_dummy_policy,
1606 	.empty_dir		= ext4_empty_dir,
1607 	.has_stable_inodes	= ext4_has_stable_inodes,
1608 	.get_ino_and_lblk_bits	= ext4_get_ino_and_lblk_bits,
1609 };
1610 #endif
1611 
1612 #ifdef CONFIG_QUOTA
1613 static const char * const quotatypes[] = INITQFNAMES;
1614 #define QTYPE2NAME(t) (quotatypes[t])
1615 
1616 static int ext4_write_dquot(struct dquot *dquot);
1617 static int ext4_acquire_dquot(struct dquot *dquot);
1618 static int ext4_release_dquot(struct dquot *dquot);
1619 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1620 static int ext4_write_info(struct super_block *sb, int type);
1621 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1622 			 const struct path *path);
1623 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1624 			       size_t len, loff_t off);
1625 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1626 				const char *data, size_t len, loff_t off);
1627 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1628 			     unsigned int flags);
1629 
1630 static struct dquot **ext4_get_dquots(struct inode *inode)
1631 {
1632 	return EXT4_I(inode)->i_dquot;
1633 }
1634 
1635 static const struct dquot_operations ext4_quota_operations = {
1636 	.get_reserved_space	= ext4_get_reserved_space,
1637 	.write_dquot		= ext4_write_dquot,
1638 	.acquire_dquot		= ext4_acquire_dquot,
1639 	.release_dquot		= ext4_release_dquot,
1640 	.mark_dirty		= ext4_mark_dquot_dirty,
1641 	.write_info		= ext4_write_info,
1642 	.alloc_dquot		= dquot_alloc,
1643 	.destroy_dquot		= dquot_destroy,
1644 	.get_projid		= ext4_get_projid,
1645 	.get_inode_usage	= ext4_get_inode_usage,
1646 	.get_next_id		= dquot_get_next_id,
1647 };
1648 
1649 static const struct quotactl_ops ext4_qctl_operations = {
1650 	.quota_on	= ext4_quota_on,
1651 	.quota_off	= ext4_quota_off,
1652 	.quota_sync	= dquot_quota_sync,
1653 	.get_state	= dquot_get_state,
1654 	.set_info	= dquot_set_dqinfo,
1655 	.get_dqblk	= dquot_get_dqblk,
1656 	.set_dqblk	= dquot_set_dqblk,
1657 	.get_nextdqblk	= dquot_get_next_dqblk,
1658 };
1659 #endif
1660 
1661 static const struct super_operations ext4_sops = {
1662 	.alloc_inode	= ext4_alloc_inode,
1663 	.free_inode	= ext4_free_in_core_inode,
1664 	.destroy_inode	= ext4_destroy_inode,
1665 	.write_inode	= ext4_write_inode,
1666 	.dirty_inode	= ext4_dirty_inode,
1667 	.drop_inode	= ext4_drop_inode,
1668 	.evict_inode	= ext4_evict_inode,
1669 	.put_super	= ext4_put_super,
1670 	.sync_fs	= ext4_sync_fs,
1671 	.freeze_fs	= ext4_freeze,
1672 	.unfreeze_fs	= ext4_unfreeze,
1673 	.statfs		= ext4_statfs,
1674 	.show_options	= ext4_show_options,
1675 #ifdef CONFIG_QUOTA
1676 	.quota_read	= ext4_quota_read,
1677 	.quota_write	= ext4_quota_write,
1678 	.get_dquots	= ext4_get_dquots,
1679 #endif
1680 };
1681 
1682 static const struct export_operations ext4_export_ops = {
1683 	.fh_to_dentry = ext4_fh_to_dentry,
1684 	.fh_to_parent = ext4_fh_to_parent,
1685 	.get_parent = ext4_get_parent,
1686 	.commit_metadata = ext4_nfs_commit_metadata,
1687 };
1688 
1689 enum {
1690 	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1691 	Opt_resgid, Opt_resuid, Opt_sb,
1692 	Opt_nouid32, Opt_debug, Opt_removed,
1693 	Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1694 	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1695 	Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1696 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1697 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1698 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1699 	Opt_inlinecrypt,
1700 	Opt_usrjquota, Opt_grpjquota, Opt_quota,
1701 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1702 	Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1703 	Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1704 	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1705 	Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1706 	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1707 	Opt_inode_readahead_blks, Opt_journal_ioprio,
1708 	Opt_dioread_nolock, Opt_dioread_lock,
1709 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1710 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1711 	Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1712 	Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1713 #ifdef CONFIG_EXT4_DEBUG
1714 	Opt_fc_debug_max_replay, Opt_fc_debug_force
1715 #endif
1716 };
1717 
1718 static const struct constant_table ext4_param_errors[] = {
1719 	{"continue",	EXT4_MOUNT_ERRORS_CONT},
1720 	{"panic",	EXT4_MOUNT_ERRORS_PANIC},
1721 	{"remount-ro",	EXT4_MOUNT_ERRORS_RO},
1722 	{}
1723 };
1724 
1725 static const struct constant_table ext4_param_data[] = {
1726 	{"journal",	EXT4_MOUNT_JOURNAL_DATA},
1727 	{"ordered",	EXT4_MOUNT_ORDERED_DATA},
1728 	{"writeback",	EXT4_MOUNT_WRITEBACK_DATA},
1729 	{}
1730 };
1731 
1732 static const struct constant_table ext4_param_data_err[] = {
1733 	{"abort",	Opt_data_err_abort},
1734 	{"ignore",	Opt_data_err_ignore},
1735 	{}
1736 };
1737 
1738 static const struct constant_table ext4_param_jqfmt[] = {
1739 	{"vfsold",	QFMT_VFS_OLD},
1740 	{"vfsv0",	QFMT_VFS_V0},
1741 	{"vfsv1",	QFMT_VFS_V1},
1742 	{}
1743 };
1744 
1745 static const struct constant_table ext4_param_dax[] = {
1746 	{"always",	Opt_dax_always},
1747 	{"inode",	Opt_dax_inode},
1748 	{"never",	Opt_dax_never},
1749 	{}
1750 };
1751 
1752 /* String parameter that allows empty argument */
1753 #define fsparam_string_empty(NAME, OPT) \
1754 	__fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1755 
1756 /*
1757  * Mount option specification
1758  * We don't use fsparam_flag_no because of the way we set the
1759  * options and the way we show them in _ext4_show_options(). To
1760  * keep the changes to a minimum, let's keep the negative options
1761  * separate for now.
1762  */
1763 static const struct fs_parameter_spec ext4_param_specs[] = {
1764 	fsparam_flag	("bsddf",		Opt_bsd_df),
1765 	fsparam_flag	("minixdf",		Opt_minix_df),
1766 	fsparam_flag	("grpid",		Opt_grpid),
1767 	fsparam_flag	("bsdgroups",		Opt_grpid),
1768 	fsparam_flag	("nogrpid",		Opt_nogrpid),
1769 	fsparam_flag	("sysvgroups",		Opt_nogrpid),
1770 	fsparam_u32	("resgid",		Opt_resgid),
1771 	fsparam_u32	("resuid",		Opt_resuid),
1772 	fsparam_u32	("sb",			Opt_sb),
1773 	fsparam_enum	("errors",		Opt_errors, ext4_param_errors),
1774 	fsparam_flag	("nouid32",		Opt_nouid32),
1775 	fsparam_flag	("debug",		Opt_debug),
1776 	fsparam_flag	("oldalloc",		Opt_removed),
1777 	fsparam_flag	("orlov",		Opt_removed),
1778 	fsparam_flag	("user_xattr",		Opt_user_xattr),
1779 	fsparam_flag	("nouser_xattr",	Opt_nouser_xattr),
1780 	fsparam_flag	("acl",			Opt_acl),
1781 	fsparam_flag	("noacl",		Opt_noacl),
1782 	fsparam_flag	("norecovery",		Opt_noload),
1783 	fsparam_flag	("noload",		Opt_noload),
1784 	fsparam_flag	("bh",			Opt_removed),
1785 	fsparam_flag	("nobh",		Opt_removed),
1786 	fsparam_u32	("commit",		Opt_commit),
1787 	fsparam_u32	("min_batch_time",	Opt_min_batch_time),
1788 	fsparam_u32	("max_batch_time",	Opt_max_batch_time),
1789 	fsparam_u32	("journal_dev",		Opt_journal_dev),
1790 	fsparam_bdev	("journal_path",	Opt_journal_path),
1791 	fsparam_flag	("journal_checksum",	Opt_journal_checksum),
1792 	fsparam_flag	("nojournal_checksum",	Opt_nojournal_checksum),
1793 	fsparam_flag	("journal_async_commit",Opt_journal_async_commit),
1794 	fsparam_flag	("abort",		Opt_abort),
1795 	fsparam_enum	("data",		Opt_data, ext4_param_data),
1796 	fsparam_enum	("data_err",		Opt_data_err,
1797 						ext4_param_data_err),
1798 	fsparam_string_empty
1799 			("usrjquota",		Opt_usrjquota),
1800 	fsparam_string_empty
1801 			("grpjquota",		Opt_grpjquota),
1802 	fsparam_enum	("jqfmt",		Opt_jqfmt, ext4_param_jqfmt),
1803 	fsparam_flag	("grpquota",		Opt_grpquota),
1804 	fsparam_flag	("quota",		Opt_quota),
1805 	fsparam_flag	("noquota",		Opt_noquota),
1806 	fsparam_flag	("usrquota",		Opt_usrquota),
1807 	fsparam_flag	("prjquota",		Opt_prjquota),
1808 	fsparam_flag	("barrier",		Opt_barrier),
1809 	fsparam_u32	("barrier",		Opt_barrier),
1810 	fsparam_flag	("nobarrier",		Opt_nobarrier),
1811 	fsparam_flag	("i_version",		Opt_i_version),
1812 	fsparam_flag	("dax",			Opt_dax),
1813 	fsparam_enum	("dax",			Opt_dax_type, ext4_param_dax),
1814 	fsparam_u32	("stripe",		Opt_stripe),
1815 	fsparam_flag	("delalloc",		Opt_delalloc),
1816 	fsparam_flag	("nodelalloc",		Opt_nodelalloc),
1817 	fsparam_flag	("warn_on_error",	Opt_warn_on_error),
1818 	fsparam_flag	("nowarn_on_error",	Opt_nowarn_on_error),
1819 	fsparam_u32	("debug_want_extra_isize",
1820 						Opt_debug_want_extra_isize),
1821 	fsparam_flag	("mblk_io_submit",	Opt_removed),
1822 	fsparam_flag	("nomblk_io_submit",	Opt_removed),
1823 	fsparam_flag	("block_validity",	Opt_block_validity),
1824 	fsparam_flag	("noblock_validity",	Opt_noblock_validity),
1825 	fsparam_u32	("inode_readahead_blks",
1826 						Opt_inode_readahead_blks),
1827 	fsparam_u32	("journal_ioprio",	Opt_journal_ioprio),
1828 	fsparam_u32	("auto_da_alloc",	Opt_auto_da_alloc),
1829 	fsparam_flag	("auto_da_alloc",	Opt_auto_da_alloc),
1830 	fsparam_flag	("noauto_da_alloc",	Opt_noauto_da_alloc),
1831 	fsparam_flag	("dioread_nolock",	Opt_dioread_nolock),
1832 	fsparam_flag	("nodioread_nolock",	Opt_dioread_lock),
1833 	fsparam_flag	("dioread_lock",	Opt_dioread_lock),
1834 	fsparam_flag	("discard",		Opt_discard),
1835 	fsparam_flag	("nodiscard",		Opt_nodiscard),
1836 	fsparam_u32	("init_itable",		Opt_init_itable),
1837 	fsparam_flag	("init_itable",		Opt_init_itable),
1838 	fsparam_flag	("noinit_itable",	Opt_noinit_itable),
1839 #ifdef CONFIG_EXT4_DEBUG
1840 	fsparam_flag	("fc_debug_force",	Opt_fc_debug_force),
1841 	fsparam_u32	("fc_debug_max_replay",	Opt_fc_debug_max_replay),
1842 #endif
1843 	fsparam_u32	("max_dir_size_kb",	Opt_max_dir_size_kb),
1844 	fsparam_flag	("test_dummy_encryption",
1845 						Opt_test_dummy_encryption),
1846 	fsparam_string	("test_dummy_encryption",
1847 						Opt_test_dummy_encryption),
1848 	fsparam_flag	("inlinecrypt",		Opt_inlinecrypt),
1849 	fsparam_flag	("nombcache",		Opt_nombcache),
1850 	fsparam_flag	("no_mbcache",		Opt_nombcache),	/* for backward compatibility */
1851 	fsparam_flag	("prefetch_block_bitmaps",
1852 						Opt_removed),
1853 	fsparam_flag	("no_prefetch_block_bitmaps",
1854 						Opt_no_prefetch_block_bitmaps),
1855 	fsparam_s32	("mb_optimize_scan",	Opt_mb_optimize_scan),
1856 	fsparam_string	("check",		Opt_removed),	/* mount option from ext2/3 */
1857 	fsparam_flag	("nocheck",		Opt_removed),	/* mount option from ext2/3 */
1858 	fsparam_flag	("reservation",		Opt_removed),	/* mount option from ext2/3 */
1859 	fsparam_flag	("noreservation",	Opt_removed),	/* mount option from ext2/3 */
1860 	fsparam_u32	("journal",		Opt_removed),	/* mount option from ext2/3 */
1861 	{}
1862 };
1863 
1864 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1865 #define DEFAULT_MB_OPTIMIZE_SCAN	(-1)
1866 
1867 static const char deprecated_msg[] =
1868 	"Mount option \"%s\" will be removed by %s\n"
1869 	"Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1870 
1871 #define MOPT_SET	0x0001
1872 #define MOPT_CLEAR	0x0002
1873 #define MOPT_NOSUPPORT	0x0004
1874 #define MOPT_EXPLICIT	0x0008
1875 #ifdef CONFIG_QUOTA
1876 #define MOPT_Q		0
1877 #define MOPT_QFMT	0x0010
1878 #else
1879 #define MOPT_Q		MOPT_NOSUPPORT
1880 #define MOPT_QFMT	MOPT_NOSUPPORT
1881 #endif
1882 #define MOPT_NO_EXT2	0x0020
1883 #define MOPT_NO_EXT3	0x0040
1884 #define MOPT_EXT4_ONLY	(MOPT_NO_EXT2 | MOPT_NO_EXT3)
1885 #define MOPT_SKIP	0x0080
1886 #define	MOPT_2		0x0100
1887 
1888 static const struct mount_opts {
1889 	int	token;
1890 	int	mount_opt;
1891 	int	flags;
1892 } ext4_mount_opts[] = {
1893 	{Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1894 	{Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1895 	{Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1896 	{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1897 	{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1898 	{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1899 	{Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1900 	 MOPT_EXT4_ONLY | MOPT_SET},
1901 	{Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1902 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1903 	{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1904 	{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1905 	{Opt_delalloc, EXT4_MOUNT_DELALLOC,
1906 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1907 	{Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1908 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1909 	{Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1910 	{Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1911 	{Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1912 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1913 	{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1914 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1915 	{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1916 				    EXT4_MOUNT_JOURNAL_CHECKSUM),
1917 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1918 	{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1919 	{Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1920 	{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1921 	{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1922 	{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1923 	{Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1924 	{Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1925 	{Opt_dax_type, 0, MOPT_EXT4_ONLY},
1926 	{Opt_journal_dev, 0, MOPT_NO_EXT2},
1927 	{Opt_journal_path, 0, MOPT_NO_EXT2},
1928 	{Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1929 	{Opt_data, 0, MOPT_NO_EXT2},
1930 	{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1931 	{Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1932 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1933 	{Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1934 	{Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1935 #else
1936 	{Opt_acl, 0, MOPT_NOSUPPORT},
1937 	{Opt_noacl, 0, MOPT_NOSUPPORT},
1938 #endif
1939 	{Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1940 	{Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1941 	{Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1942 	{Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1943 							MOPT_SET | MOPT_Q},
1944 	{Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1945 							MOPT_SET | MOPT_Q},
1946 	{Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1947 							MOPT_SET | MOPT_Q},
1948 	{Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1949 		       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1950 							MOPT_CLEAR | MOPT_Q},
1951 	{Opt_usrjquota, 0, MOPT_Q},
1952 	{Opt_grpjquota, 0, MOPT_Q},
1953 	{Opt_jqfmt, 0, MOPT_QFMT},
1954 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1955 	{Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1956 	 MOPT_SET},
1957 #ifdef CONFIG_EXT4_DEBUG
1958 	{Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1959 	 MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1960 #endif
1961 	{Opt_err, 0, 0}
1962 };
1963 
1964 #ifdef CONFIG_UNICODE
1965 static const struct ext4_sb_encodings {
1966 	__u16 magic;
1967 	char *name;
1968 	unsigned int version;
1969 } ext4_sb_encoding_map[] = {
1970 	{EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1971 };
1972 
1973 static const struct ext4_sb_encodings *
1974 ext4_sb_read_encoding(const struct ext4_super_block *es)
1975 {
1976 	__u16 magic = le16_to_cpu(es->s_encoding);
1977 	int i;
1978 
1979 	for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1980 		if (magic == ext4_sb_encoding_map[i].magic)
1981 			return &ext4_sb_encoding_map[i];
1982 
1983 	return NULL;
1984 }
1985 #endif
1986 
1987 static int ext4_set_test_dummy_encryption(struct super_block *sb, char *arg)
1988 {
1989 #ifdef CONFIG_FS_ENCRYPTION
1990 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1991 	int err;
1992 
1993 	err = fscrypt_set_test_dummy_encryption(sb, arg,
1994 						&sbi->s_dummy_enc_policy);
1995 	if (err) {
1996 		ext4_msg(sb, KERN_WARNING,
1997 			 "Error while setting test dummy encryption [%d]", err);
1998 		return err;
1999 	}
2000 	ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2001 #endif
2002 	return 0;
2003 }
2004 
2005 #define EXT4_SPEC_JQUOTA			(1 <<  0)
2006 #define EXT4_SPEC_JQFMT				(1 <<  1)
2007 #define EXT4_SPEC_DATAJ				(1 <<  2)
2008 #define EXT4_SPEC_SB_BLOCK			(1 <<  3)
2009 #define EXT4_SPEC_JOURNAL_DEV			(1 <<  4)
2010 #define EXT4_SPEC_JOURNAL_IOPRIO		(1 <<  5)
2011 #define EXT4_SPEC_DUMMY_ENCRYPTION		(1 <<  6)
2012 #define EXT4_SPEC_s_want_extra_isize		(1 <<  7)
2013 #define EXT4_SPEC_s_max_batch_time		(1 <<  8)
2014 #define EXT4_SPEC_s_min_batch_time		(1 <<  9)
2015 #define EXT4_SPEC_s_inode_readahead_blks	(1 << 10)
2016 #define EXT4_SPEC_s_li_wait_mult		(1 << 11)
2017 #define EXT4_SPEC_s_max_dir_size_kb		(1 << 12)
2018 #define EXT4_SPEC_s_stripe			(1 << 13)
2019 #define EXT4_SPEC_s_resuid			(1 << 14)
2020 #define EXT4_SPEC_s_resgid			(1 << 15)
2021 #define EXT4_SPEC_s_commit_interval		(1 << 16)
2022 #define EXT4_SPEC_s_fc_debug_max_replay		(1 << 17)
2023 #define EXT4_SPEC_s_sb_block			(1 << 18)
2024 
2025 struct ext4_fs_context {
2026 	char		*s_qf_names[EXT4_MAXQUOTAS];
2027 	char		*test_dummy_enc_arg;
2028 	int		s_jquota_fmt;	/* Format of quota to use */
2029 	int		mb_optimize_scan;
2030 #ifdef CONFIG_EXT4_DEBUG
2031 	int s_fc_debug_max_replay;
2032 #endif
2033 	unsigned short	qname_spec;
2034 	unsigned long	vals_s_flags;	/* Bits to set in s_flags */
2035 	unsigned long	mask_s_flags;	/* Bits changed in s_flags */
2036 	unsigned long	journal_devnum;
2037 	unsigned long	s_commit_interval;
2038 	unsigned long	s_stripe;
2039 	unsigned int	s_inode_readahead_blks;
2040 	unsigned int	s_want_extra_isize;
2041 	unsigned int	s_li_wait_mult;
2042 	unsigned int	s_max_dir_size_kb;
2043 	unsigned int	journal_ioprio;
2044 	unsigned int	vals_s_mount_opt;
2045 	unsigned int	mask_s_mount_opt;
2046 	unsigned int	vals_s_mount_opt2;
2047 	unsigned int	mask_s_mount_opt2;
2048 	unsigned int	vals_s_mount_flags;
2049 	unsigned int	mask_s_mount_flags;
2050 	unsigned int	opt_flags;	/* MOPT flags */
2051 	unsigned int	spec;
2052 	u32		s_max_batch_time;
2053 	u32		s_min_batch_time;
2054 	kuid_t		s_resuid;
2055 	kgid_t		s_resgid;
2056 	ext4_fsblk_t	s_sb_block;
2057 };
2058 
2059 static void ext4_fc_free(struct fs_context *fc)
2060 {
2061 	struct ext4_fs_context *ctx = fc->fs_private;
2062 	int i;
2063 
2064 	if (!ctx)
2065 		return;
2066 
2067 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
2068 		kfree(ctx->s_qf_names[i]);
2069 
2070 	kfree(ctx->test_dummy_enc_arg);
2071 	kfree(ctx);
2072 }
2073 
2074 int ext4_init_fs_context(struct fs_context *fc)
2075 {
2076 	struct ext4_fs_context *ctx;
2077 
2078 	ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2079 	if (!ctx)
2080 		return -ENOMEM;
2081 
2082 	fc->fs_private = ctx;
2083 	fc->ops = &ext4_context_ops;
2084 
2085 	return 0;
2086 }
2087 
2088 #ifdef CONFIG_QUOTA
2089 /*
2090  * Note the name of the specified quota file.
2091  */
2092 static int note_qf_name(struct fs_context *fc, int qtype,
2093 		       struct fs_parameter *param)
2094 {
2095 	struct ext4_fs_context *ctx = fc->fs_private;
2096 	char *qname;
2097 
2098 	if (param->size < 1) {
2099 		ext4_msg(NULL, KERN_ERR, "Missing quota name");
2100 		return -EINVAL;
2101 	}
2102 	if (strchr(param->string, '/')) {
2103 		ext4_msg(NULL, KERN_ERR,
2104 			 "quotafile must be on filesystem root");
2105 		return -EINVAL;
2106 	}
2107 	if (ctx->s_qf_names[qtype]) {
2108 		if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2109 			ext4_msg(NULL, KERN_ERR,
2110 				 "%s quota file already specified",
2111 				 QTYPE2NAME(qtype));
2112 			return -EINVAL;
2113 		}
2114 		return 0;
2115 	}
2116 
2117 	qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2118 	if (!qname) {
2119 		ext4_msg(NULL, KERN_ERR,
2120 			 "Not enough memory for storing quotafile name");
2121 		return -ENOMEM;
2122 	}
2123 	ctx->s_qf_names[qtype] = qname;
2124 	ctx->qname_spec |= 1 << qtype;
2125 	ctx->spec |= EXT4_SPEC_JQUOTA;
2126 	return 0;
2127 }
2128 
2129 /*
2130  * Clear the name of the specified quota file.
2131  */
2132 static int unnote_qf_name(struct fs_context *fc, int qtype)
2133 {
2134 	struct ext4_fs_context *ctx = fc->fs_private;
2135 
2136 	if (ctx->s_qf_names[qtype])
2137 		kfree(ctx->s_qf_names[qtype]);
2138 
2139 	ctx->s_qf_names[qtype] = NULL;
2140 	ctx->qname_spec |= 1 << qtype;
2141 	ctx->spec |= EXT4_SPEC_JQUOTA;
2142 	return 0;
2143 }
2144 #endif
2145 
2146 #define EXT4_SET_CTX(name)						\
2147 static inline void ctx_set_##name(struct ext4_fs_context *ctx,		\
2148 				  unsigned long flag)			\
2149 {									\
2150 	ctx->mask_s_##name |= flag;					\
2151 	ctx->vals_s_##name |= flag;					\
2152 }									\
2153 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,	\
2154 				    unsigned long flag)			\
2155 {									\
2156 	ctx->mask_s_##name |= flag;					\
2157 	ctx->vals_s_##name &= ~flag;					\
2158 }									\
2159 static inline unsigned long						\
2160 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)	\
2161 {									\
2162 	return (ctx->vals_s_##name & flag);				\
2163 }									\
2164 
2165 EXT4_SET_CTX(flags);
2166 EXT4_SET_CTX(mount_opt);
2167 EXT4_SET_CTX(mount_opt2);
2168 EXT4_SET_CTX(mount_flags);
2169 
2170 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2171 {
2172 	struct ext4_fs_context *ctx = fc->fs_private;
2173 	struct fs_parse_result result;
2174 	const struct mount_opts *m;
2175 	int is_remount;
2176 	kuid_t uid;
2177 	kgid_t gid;
2178 	int token;
2179 
2180 	token = fs_parse(fc, ext4_param_specs, param, &result);
2181 	if (token < 0)
2182 		return token;
2183 	is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2184 
2185 	for (m = ext4_mount_opts; m->token != Opt_err; m++)
2186 		if (token == m->token)
2187 			break;
2188 
2189 	ctx->opt_flags |= m->flags;
2190 
2191 	if (m->flags & MOPT_EXPLICIT) {
2192 		if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2193 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2194 		} else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2195 			ctx_set_mount_opt2(ctx,
2196 				       EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2197 		} else
2198 			return -EINVAL;
2199 	}
2200 
2201 	if (m->flags & MOPT_NOSUPPORT) {
2202 		ext4_msg(NULL, KERN_ERR, "%s option not supported",
2203 			 param->key);
2204 		return 0;
2205 	}
2206 
2207 	switch (token) {
2208 #ifdef CONFIG_QUOTA
2209 	case Opt_usrjquota:
2210 		if (!*param->string)
2211 			return unnote_qf_name(fc, USRQUOTA);
2212 		else
2213 			return note_qf_name(fc, USRQUOTA, param);
2214 	case Opt_grpjquota:
2215 		if (!*param->string)
2216 			return unnote_qf_name(fc, GRPQUOTA);
2217 		else
2218 			return note_qf_name(fc, GRPQUOTA, param);
2219 #endif
2220 	case Opt_noacl:
2221 	case Opt_nouser_xattr:
2222 		ext4_msg(NULL, KERN_WARNING, deprecated_msg, param->key, "3.5");
2223 		break;
2224 	case Opt_sb:
2225 		if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2226 			ext4_msg(NULL, KERN_WARNING,
2227 				 "Ignoring %s option on remount", param->key);
2228 		} else {
2229 			ctx->s_sb_block = result.uint_32;
2230 			ctx->spec |= EXT4_SPEC_s_sb_block;
2231 		}
2232 		return 0;
2233 	case Opt_removed:
2234 		ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2235 			 param->key);
2236 		return 0;
2237 	case Opt_abort:
2238 		ctx_set_mount_flags(ctx, EXT4_MF_FS_ABORTED);
2239 		return 0;
2240 	case Opt_i_version:
2241 		ext4_msg(NULL, KERN_WARNING, deprecated_msg, param->key, "5.20");
2242 		ext4_msg(NULL, KERN_WARNING, "Use iversion instead\n");
2243 		ctx_set_flags(ctx, SB_I_VERSION);
2244 		return 0;
2245 	case Opt_inlinecrypt:
2246 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2247 		ctx_set_flags(ctx, SB_INLINECRYPT);
2248 #else
2249 		ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2250 #endif
2251 		return 0;
2252 	case Opt_errors:
2253 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2254 		ctx_set_mount_opt(ctx, result.uint_32);
2255 		return 0;
2256 #ifdef CONFIG_QUOTA
2257 	case Opt_jqfmt:
2258 		ctx->s_jquota_fmt = result.uint_32;
2259 		ctx->spec |= EXT4_SPEC_JQFMT;
2260 		return 0;
2261 #endif
2262 	case Opt_data:
2263 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2264 		ctx_set_mount_opt(ctx, result.uint_32);
2265 		ctx->spec |= EXT4_SPEC_DATAJ;
2266 		return 0;
2267 	case Opt_commit:
2268 		if (result.uint_32 == 0)
2269 			ctx->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE;
2270 		else if (result.uint_32 > INT_MAX / HZ) {
2271 			ext4_msg(NULL, KERN_ERR,
2272 				 "Invalid commit interval %d, "
2273 				 "must be smaller than %d",
2274 				 result.uint_32, INT_MAX / HZ);
2275 			return -EINVAL;
2276 		}
2277 		ctx->s_commit_interval = HZ * result.uint_32;
2278 		ctx->spec |= EXT4_SPEC_s_commit_interval;
2279 		return 0;
2280 	case Opt_debug_want_extra_isize:
2281 		if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2282 			ext4_msg(NULL, KERN_ERR,
2283 				 "Invalid want_extra_isize %d", result.uint_32);
2284 			return -EINVAL;
2285 		}
2286 		ctx->s_want_extra_isize = result.uint_32;
2287 		ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2288 		return 0;
2289 	case Opt_max_batch_time:
2290 		ctx->s_max_batch_time = result.uint_32;
2291 		ctx->spec |= EXT4_SPEC_s_max_batch_time;
2292 		return 0;
2293 	case Opt_min_batch_time:
2294 		ctx->s_min_batch_time = result.uint_32;
2295 		ctx->spec |= EXT4_SPEC_s_min_batch_time;
2296 		return 0;
2297 	case Opt_inode_readahead_blks:
2298 		if (result.uint_32 &&
2299 		    (result.uint_32 > (1 << 30) ||
2300 		     !is_power_of_2(result.uint_32))) {
2301 			ext4_msg(NULL, KERN_ERR,
2302 				 "EXT4-fs: inode_readahead_blks must be "
2303 				 "0 or a power of 2 smaller than 2^31");
2304 			return -EINVAL;
2305 		}
2306 		ctx->s_inode_readahead_blks = result.uint_32;
2307 		ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2308 		return 0;
2309 	case Opt_init_itable:
2310 		ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2311 		ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2312 		if (param->type == fs_value_is_string)
2313 			ctx->s_li_wait_mult = result.uint_32;
2314 		ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2315 		return 0;
2316 	case Opt_max_dir_size_kb:
2317 		ctx->s_max_dir_size_kb = result.uint_32;
2318 		ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2319 		return 0;
2320 #ifdef CONFIG_EXT4_DEBUG
2321 	case Opt_fc_debug_max_replay:
2322 		ctx->s_fc_debug_max_replay = result.uint_32;
2323 		ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2324 		return 0;
2325 #endif
2326 	case Opt_stripe:
2327 		ctx->s_stripe = result.uint_32;
2328 		ctx->spec |= EXT4_SPEC_s_stripe;
2329 		return 0;
2330 	case Opt_resuid:
2331 		uid = make_kuid(current_user_ns(), result.uint_32);
2332 		if (!uid_valid(uid)) {
2333 			ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2334 				 result.uint_32);
2335 			return -EINVAL;
2336 		}
2337 		ctx->s_resuid = uid;
2338 		ctx->spec |= EXT4_SPEC_s_resuid;
2339 		return 0;
2340 	case Opt_resgid:
2341 		gid = make_kgid(current_user_ns(), result.uint_32);
2342 		if (!gid_valid(gid)) {
2343 			ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2344 				 result.uint_32);
2345 			return -EINVAL;
2346 		}
2347 		ctx->s_resgid = gid;
2348 		ctx->spec |= EXT4_SPEC_s_resgid;
2349 		return 0;
2350 	case Opt_journal_dev:
2351 		if (is_remount) {
2352 			ext4_msg(NULL, KERN_ERR,
2353 				 "Cannot specify journal on remount");
2354 			return -EINVAL;
2355 		}
2356 		ctx->journal_devnum = result.uint_32;
2357 		ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2358 		return 0;
2359 	case Opt_journal_path:
2360 	{
2361 		struct inode *journal_inode;
2362 		struct path path;
2363 		int error;
2364 
2365 		if (is_remount) {
2366 			ext4_msg(NULL, KERN_ERR,
2367 				 "Cannot specify journal on remount");
2368 			return -EINVAL;
2369 		}
2370 
2371 		error = fs_lookup_param(fc, param, 1, &path);
2372 		if (error) {
2373 			ext4_msg(NULL, KERN_ERR, "error: could not find "
2374 				 "journal device path");
2375 			return -EINVAL;
2376 		}
2377 
2378 		journal_inode = d_inode(path.dentry);
2379 		ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2380 		ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2381 		path_put(&path);
2382 		return 0;
2383 	}
2384 	case Opt_journal_ioprio:
2385 		if (result.uint_32 > 7) {
2386 			ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2387 				 " (must be 0-7)");
2388 			return -EINVAL;
2389 		}
2390 		ctx->journal_ioprio =
2391 			IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2392 		ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2393 		return 0;
2394 	case Opt_test_dummy_encryption:
2395 #ifdef CONFIG_FS_ENCRYPTION
2396 		if (param->type == fs_value_is_flag) {
2397 			ctx->spec |= EXT4_SPEC_DUMMY_ENCRYPTION;
2398 			ctx->test_dummy_enc_arg = NULL;
2399 			return 0;
2400 		}
2401 		if (*param->string &&
2402 		    !(!strcmp(param->string, "v1") ||
2403 		      !strcmp(param->string, "v2"))) {
2404 			ext4_msg(NULL, KERN_WARNING,
2405 				 "Value of option \"%s\" is unrecognized",
2406 				 param->key);
2407 			return -EINVAL;
2408 		}
2409 		ctx->spec |= EXT4_SPEC_DUMMY_ENCRYPTION;
2410 		ctx->test_dummy_enc_arg = kmemdup_nul(param->string, param->size,
2411 						      GFP_KERNEL);
2412 #else
2413 		ext4_msg(NULL, KERN_WARNING,
2414 			 "Test dummy encryption mount option ignored");
2415 #endif
2416 		return 0;
2417 	case Opt_dax:
2418 	case Opt_dax_type:
2419 #ifdef CONFIG_FS_DAX
2420 	{
2421 		int type = (token == Opt_dax) ?
2422 			   Opt_dax : result.uint_32;
2423 
2424 		switch (type) {
2425 		case Opt_dax:
2426 		case Opt_dax_always:
2427 			ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2428 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2429 			break;
2430 		case Opt_dax_never:
2431 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2432 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2433 			break;
2434 		case Opt_dax_inode:
2435 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2436 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2437 			/* Strictly for printing options */
2438 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2439 			break;
2440 		}
2441 		return 0;
2442 	}
2443 #else
2444 		ext4_msg(NULL, KERN_INFO, "dax option not supported");
2445 		return -EINVAL;
2446 #endif
2447 	case Opt_data_err:
2448 		if (result.uint_32 == Opt_data_err_abort)
2449 			ctx_set_mount_opt(ctx, m->mount_opt);
2450 		else if (result.uint_32 == Opt_data_err_ignore)
2451 			ctx_clear_mount_opt(ctx, m->mount_opt);
2452 		return 0;
2453 	case Opt_mb_optimize_scan:
2454 		if (result.int_32 != 0 && result.int_32 != 1) {
2455 			ext4_msg(NULL, KERN_WARNING,
2456 				 "mb_optimize_scan should be set to 0 or 1.");
2457 			return -EINVAL;
2458 		}
2459 		ctx->mb_optimize_scan = result.int_32;
2460 		return 0;
2461 	}
2462 
2463 	/*
2464 	 * At this point we should only be getting options requiring MOPT_SET,
2465 	 * or MOPT_CLEAR. Anything else is a bug
2466 	 */
2467 	if (m->token == Opt_err) {
2468 		ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2469 			 param->key);
2470 		WARN_ON(1);
2471 		return -EINVAL;
2472 	}
2473 
2474 	else {
2475 		unsigned int set = 0;
2476 
2477 		if ((param->type == fs_value_is_flag) ||
2478 		    result.uint_32 > 0)
2479 			set = 1;
2480 
2481 		if (m->flags & MOPT_CLEAR)
2482 			set = !set;
2483 		else if (unlikely(!(m->flags & MOPT_SET))) {
2484 			ext4_msg(NULL, KERN_WARNING,
2485 				 "buggy handling of option %s",
2486 				 param->key);
2487 			WARN_ON(1);
2488 			return -EINVAL;
2489 		}
2490 		if (m->flags & MOPT_2) {
2491 			if (set != 0)
2492 				ctx_set_mount_opt2(ctx, m->mount_opt);
2493 			else
2494 				ctx_clear_mount_opt2(ctx, m->mount_opt);
2495 		} else {
2496 			if (set != 0)
2497 				ctx_set_mount_opt(ctx, m->mount_opt);
2498 			else
2499 				ctx_clear_mount_opt(ctx, m->mount_opt);
2500 		}
2501 	}
2502 
2503 	return 0;
2504 }
2505 
2506 static int parse_options(struct fs_context *fc, char *options)
2507 {
2508 	struct fs_parameter param;
2509 	int ret;
2510 	char *key;
2511 
2512 	if (!options)
2513 		return 0;
2514 
2515 	while ((key = strsep(&options, ",")) != NULL) {
2516 		if (*key) {
2517 			size_t v_len = 0;
2518 			char *value = strchr(key, '=');
2519 
2520 			param.type = fs_value_is_flag;
2521 			param.string = NULL;
2522 
2523 			if (value) {
2524 				if (value == key)
2525 					continue;
2526 
2527 				*value++ = 0;
2528 				v_len = strlen(value);
2529 				param.string = kmemdup_nul(value, v_len,
2530 							   GFP_KERNEL);
2531 				if (!param.string)
2532 					return -ENOMEM;
2533 				param.type = fs_value_is_string;
2534 			}
2535 
2536 			param.key = key;
2537 			param.size = v_len;
2538 
2539 			ret = ext4_parse_param(fc, &param);
2540 			if (param.string)
2541 				kfree(param.string);
2542 			if (ret < 0)
2543 				return ret;
2544 		}
2545 	}
2546 
2547 	ret = ext4_validate_options(fc);
2548 	if (ret < 0)
2549 		return ret;
2550 
2551 	return 0;
2552 }
2553 
2554 static int parse_apply_sb_mount_options(struct super_block *sb,
2555 					struct ext4_fs_context *m_ctx)
2556 {
2557 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2558 	char *s_mount_opts = NULL;
2559 	struct ext4_fs_context *s_ctx = NULL;
2560 	struct fs_context *fc = NULL;
2561 	int ret = -ENOMEM;
2562 
2563 	if (!sbi->s_es->s_mount_opts[0])
2564 		return 0;
2565 
2566 	s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2567 				sizeof(sbi->s_es->s_mount_opts),
2568 				GFP_KERNEL);
2569 	if (!s_mount_opts)
2570 		return ret;
2571 
2572 	fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2573 	if (!fc)
2574 		goto out_free;
2575 
2576 	s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2577 	if (!s_ctx)
2578 		goto out_free;
2579 
2580 	fc->fs_private = s_ctx;
2581 	fc->s_fs_info = sbi;
2582 
2583 	ret = parse_options(fc, s_mount_opts);
2584 	if (ret < 0)
2585 		goto parse_failed;
2586 
2587 	ret = ext4_check_opt_consistency(fc, sb);
2588 	if (ret < 0) {
2589 parse_failed:
2590 		ext4_msg(sb, KERN_WARNING,
2591 			 "failed to parse options in superblock: %s",
2592 			 s_mount_opts);
2593 		ret = 0;
2594 		goto out_free;
2595 	}
2596 
2597 	if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2598 		m_ctx->journal_devnum = s_ctx->journal_devnum;
2599 	if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2600 		m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2601 
2602 	ret = ext4_apply_options(fc, sb);
2603 
2604 out_free:
2605 	kfree(s_ctx);
2606 	kfree(fc);
2607 	kfree(s_mount_opts);
2608 	return ret;
2609 }
2610 
2611 static void ext4_apply_quota_options(struct fs_context *fc,
2612 				     struct super_block *sb)
2613 {
2614 #ifdef CONFIG_QUOTA
2615 	bool quota_feature = ext4_has_feature_quota(sb);
2616 	struct ext4_fs_context *ctx = fc->fs_private;
2617 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2618 	char *qname;
2619 	int i;
2620 
2621 	if (quota_feature)
2622 		return;
2623 
2624 	if (ctx->spec & EXT4_SPEC_JQUOTA) {
2625 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2626 			if (!(ctx->qname_spec & (1 << i)))
2627 				continue;
2628 
2629 			qname = ctx->s_qf_names[i]; /* May be NULL */
2630 			if (qname)
2631 				set_opt(sb, QUOTA);
2632 			ctx->s_qf_names[i] = NULL;
2633 			qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2634 						lockdep_is_held(&sb->s_umount));
2635 			if (qname)
2636 				kfree_rcu(qname);
2637 		}
2638 	}
2639 
2640 	if (ctx->spec & EXT4_SPEC_JQFMT)
2641 		sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2642 #endif
2643 }
2644 
2645 /*
2646  * Check quota settings consistency.
2647  */
2648 static int ext4_check_quota_consistency(struct fs_context *fc,
2649 					struct super_block *sb)
2650 {
2651 #ifdef CONFIG_QUOTA
2652 	struct ext4_fs_context *ctx = fc->fs_private;
2653 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2654 	bool quota_feature = ext4_has_feature_quota(sb);
2655 	bool quota_loaded = sb_any_quota_loaded(sb);
2656 	bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2657 	int quota_flags, i;
2658 
2659 	/*
2660 	 * We do the test below only for project quotas. 'usrquota' and
2661 	 * 'grpquota' mount options are allowed even without quota feature
2662 	 * to support legacy quotas in quota files.
2663 	 */
2664 	if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2665 	    !ext4_has_feature_project(sb)) {
2666 		ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2667 			 "Cannot enable project quota enforcement.");
2668 		return -EINVAL;
2669 	}
2670 
2671 	quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2672 		      EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2673 	if (quota_loaded &&
2674 	    ctx->mask_s_mount_opt & quota_flags &&
2675 	    !ctx_test_mount_opt(ctx, quota_flags))
2676 		goto err_quota_change;
2677 
2678 	if (ctx->spec & EXT4_SPEC_JQUOTA) {
2679 
2680 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2681 			if (!(ctx->qname_spec & (1 << i)))
2682 				continue;
2683 
2684 			if (quota_loaded &&
2685 			    !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2686 				goto err_jquota_change;
2687 
2688 			if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2689 			    strcmp(get_qf_name(sb, sbi, i),
2690 				   ctx->s_qf_names[i]) != 0)
2691 				goto err_jquota_specified;
2692 		}
2693 
2694 		if (quota_feature) {
2695 			ext4_msg(NULL, KERN_INFO,
2696 				 "Journaled quota options ignored when "
2697 				 "QUOTA feature is enabled");
2698 			return 0;
2699 		}
2700 	}
2701 
2702 	if (ctx->spec & EXT4_SPEC_JQFMT) {
2703 		if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2704 			goto err_jquota_change;
2705 		if (quota_feature) {
2706 			ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2707 				 "ignored when QUOTA feature is enabled");
2708 			return 0;
2709 		}
2710 	}
2711 
2712 	/* Make sure we don't mix old and new quota format */
2713 	usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2714 		       ctx->s_qf_names[USRQUOTA]);
2715 	grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2716 		       ctx->s_qf_names[GRPQUOTA]);
2717 
2718 	usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2719 		    test_opt(sb, USRQUOTA));
2720 
2721 	grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2722 		    test_opt(sb, GRPQUOTA));
2723 
2724 	if (usr_qf_name) {
2725 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2726 		usrquota = false;
2727 	}
2728 	if (grp_qf_name) {
2729 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2730 		grpquota = false;
2731 	}
2732 
2733 	if (usr_qf_name || grp_qf_name) {
2734 		if (usrquota || grpquota) {
2735 			ext4_msg(NULL, KERN_ERR, "old and new quota "
2736 				 "format mixing");
2737 			return -EINVAL;
2738 		}
2739 
2740 		if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2741 			ext4_msg(NULL, KERN_ERR, "journaled quota format "
2742 				 "not specified");
2743 			return -EINVAL;
2744 		}
2745 	}
2746 
2747 	return 0;
2748 
2749 err_quota_change:
2750 	ext4_msg(NULL, KERN_ERR,
2751 		 "Cannot change quota options when quota turned on");
2752 	return -EINVAL;
2753 err_jquota_change:
2754 	ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2755 		 "options when quota turned on");
2756 	return -EINVAL;
2757 err_jquota_specified:
2758 	ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2759 		 QTYPE2NAME(i));
2760 	return -EINVAL;
2761 #else
2762 	return 0;
2763 #endif
2764 }
2765 
2766 static int ext4_check_opt_consistency(struct fs_context *fc,
2767 				      struct super_block *sb)
2768 {
2769 	struct ext4_fs_context *ctx = fc->fs_private;
2770 	struct ext4_sb_info *sbi = fc->s_fs_info;
2771 	int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2772 
2773 	if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2774 		ext4_msg(NULL, KERN_ERR,
2775 			 "Mount option(s) incompatible with ext2");
2776 		return -EINVAL;
2777 	}
2778 	if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2779 		ext4_msg(NULL, KERN_ERR,
2780 			 "Mount option(s) incompatible with ext3");
2781 		return -EINVAL;
2782 	}
2783 
2784 	if (ctx->s_want_extra_isize >
2785 	    (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2786 		ext4_msg(NULL, KERN_ERR,
2787 			 "Invalid want_extra_isize %d",
2788 			 ctx->s_want_extra_isize);
2789 		return -EINVAL;
2790 	}
2791 
2792 	if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DIOREAD_NOLOCK)) {
2793 		int blocksize =
2794 			BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2795 		if (blocksize < PAGE_SIZE)
2796 			ext4_msg(NULL, KERN_WARNING, "Warning: mounting with an "
2797 				 "experimental mount option 'dioread_nolock' "
2798 				 "for blocksize < PAGE_SIZE");
2799 	}
2800 
2801 #ifdef CONFIG_FS_ENCRYPTION
2802 	/*
2803 	 * This mount option is just for testing, and it's not worthwhile to
2804 	 * implement the extra complexity (e.g. RCU protection) that would be
2805 	 * needed to allow it to be set or changed during remount.  We do allow
2806 	 * it to be specified during remount, but only if there is no change.
2807 	 */
2808 	if ((ctx->spec & EXT4_SPEC_DUMMY_ENCRYPTION) &&
2809 	    is_remount && !sbi->s_dummy_enc_policy.policy) {
2810 		ext4_msg(NULL, KERN_WARNING,
2811 			 "Can't set test_dummy_encryption on remount");
2812 		return -1;
2813 	}
2814 #endif
2815 
2816 	if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2817 		if (!sbi->s_journal) {
2818 			ext4_msg(NULL, KERN_WARNING,
2819 				 "Remounting file system with no journal "
2820 				 "so ignoring journalled data option");
2821 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2822 		} else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2823 			   test_opt(sb, DATA_FLAGS)) {
2824 			ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2825 				 "on remount");
2826 			return -EINVAL;
2827 		}
2828 	}
2829 
2830 	if (is_remount) {
2831 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2832 		    (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2833 			ext4_msg(NULL, KERN_ERR, "can't mount with "
2834 				 "both data=journal and dax");
2835 			return -EINVAL;
2836 		}
2837 
2838 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2839 		    (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2840 		     (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2841 fail_dax_change_remount:
2842 			ext4_msg(NULL, KERN_ERR, "can't change "
2843 				 "dax mount option while remounting");
2844 			return -EINVAL;
2845 		} else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2846 			 (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2847 			  (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2848 			goto fail_dax_change_remount;
2849 		} else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2850 			   ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2851 			    (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2852 			    !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2853 			goto fail_dax_change_remount;
2854 		}
2855 	}
2856 
2857 	return ext4_check_quota_consistency(fc, sb);
2858 }
2859 
2860 static int ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2861 {
2862 	struct ext4_fs_context *ctx = fc->fs_private;
2863 	struct ext4_sb_info *sbi = fc->s_fs_info;
2864 	int ret = 0;
2865 
2866 	sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2867 	sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2868 	sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2869 	sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2870 	sbi->s_mount_flags &= ~ctx->mask_s_mount_flags;
2871 	sbi->s_mount_flags |= ctx->vals_s_mount_flags;
2872 	sb->s_flags &= ~ctx->mask_s_flags;
2873 	sb->s_flags |= ctx->vals_s_flags;
2874 
2875 	/*
2876 	 * i_version differs from common mount option iversion so we have
2877 	 * to let vfs know that it was set, otherwise it would get cleared
2878 	 * on remount
2879 	 */
2880 	if (ctx->mask_s_flags & SB_I_VERSION)
2881 		fc->sb_flags |= SB_I_VERSION;
2882 
2883 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2884 	APPLY(s_commit_interval);
2885 	APPLY(s_stripe);
2886 	APPLY(s_max_batch_time);
2887 	APPLY(s_min_batch_time);
2888 	APPLY(s_want_extra_isize);
2889 	APPLY(s_inode_readahead_blks);
2890 	APPLY(s_max_dir_size_kb);
2891 	APPLY(s_li_wait_mult);
2892 	APPLY(s_resgid);
2893 	APPLY(s_resuid);
2894 
2895 #ifdef CONFIG_EXT4_DEBUG
2896 	APPLY(s_fc_debug_max_replay);
2897 #endif
2898 
2899 	ext4_apply_quota_options(fc, sb);
2900 
2901 	if (ctx->spec & EXT4_SPEC_DUMMY_ENCRYPTION)
2902 		ret = ext4_set_test_dummy_encryption(sb, ctx->test_dummy_enc_arg);
2903 
2904 	return ret;
2905 }
2906 
2907 
2908 static int ext4_validate_options(struct fs_context *fc)
2909 {
2910 #ifdef CONFIG_QUOTA
2911 	struct ext4_fs_context *ctx = fc->fs_private;
2912 	char *usr_qf_name, *grp_qf_name;
2913 
2914 	usr_qf_name = ctx->s_qf_names[USRQUOTA];
2915 	grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2916 
2917 	if (usr_qf_name || grp_qf_name) {
2918 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2919 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2920 
2921 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2922 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2923 
2924 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2925 		    ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2926 			ext4_msg(NULL, KERN_ERR, "old and new quota "
2927 				 "format mixing");
2928 			return -EINVAL;
2929 		}
2930 	}
2931 #endif
2932 	return 1;
2933 }
2934 
2935 static inline void ext4_show_quota_options(struct seq_file *seq,
2936 					   struct super_block *sb)
2937 {
2938 #if defined(CONFIG_QUOTA)
2939 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2940 	char *usr_qf_name, *grp_qf_name;
2941 
2942 	if (sbi->s_jquota_fmt) {
2943 		char *fmtname = "";
2944 
2945 		switch (sbi->s_jquota_fmt) {
2946 		case QFMT_VFS_OLD:
2947 			fmtname = "vfsold";
2948 			break;
2949 		case QFMT_VFS_V0:
2950 			fmtname = "vfsv0";
2951 			break;
2952 		case QFMT_VFS_V1:
2953 			fmtname = "vfsv1";
2954 			break;
2955 		}
2956 		seq_printf(seq, ",jqfmt=%s", fmtname);
2957 	}
2958 
2959 	rcu_read_lock();
2960 	usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2961 	grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2962 	if (usr_qf_name)
2963 		seq_show_option(seq, "usrjquota", usr_qf_name);
2964 	if (grp_qf_name)
2965 		seq_show_option(seq, "grpjquota", grp_qf_name);
2966 	rcu_read_unlock();
2967 #endif
2968 }
2969 
2970 static const char *token2str(int token)
2971 {
2972 	const struct fs_parameter_spec *spec;
2973 
2974 	for (spec = ext4_param_specs; spec->name != NULL; spec++)
2975 		if (spec->opt == token && !spec->type)
2976 			break;
2977 	return spec->name;
2978 }
2979 
2980 /*
2981  * Show an option if
2982  *  - it's set to a non-default value OR
2983  *  - if the per-sb default is different from the global default
2984  */
2985 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2986 			      int nodefs)
2987 {
2988 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2989 	struct ext4_super_block *es = sbi->s_es;
2990 	int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2991 	const struct mount_opts *m;
2992 	char sep = nodefs ? '\n' : ',';
2993 
2994 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2995 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2996 
2997 	if (sbi->s_sb_block != 1)
2998 		SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2999 
3000 	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
3001 		int want_set = m->flags & MOPT_SET;
3002 		if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
3003 		    m->flags & MOPT_SKIP)
3004 			continue;
3005 		if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
3006 			continue; /* skip if same as the default */
3007 		if ((want_set &&
3008 		     (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
3009 		    (!want_set && (sbi->s_mount_opt & m->mount_opt)))
3010 			continue; /* select Opt_noFoo vs Opt_Foo */
3011 		SEQ_OPTS_PRINT("%s", token2str(m->token));
3012 	}
3013 
3014 	if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
3015 	    le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
3016 		SEQ_OPTS_PRINT("resuid=%u",
3017 				from_kuid_munged(&init_user_ns, sbi->s_resuid));
3018 	if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
3019 	    le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
3020 		SEQ_OPTS_PRINT("resgid=%u",
3021 				from_kgid_munged(&init_user_ns, sbi->s_resgid));
3022 	def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
3023 	if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
3024 		SEQ_OPTS_PUTS("errors=remount-ro");
3025 	if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
3026 		SEQ_OPTS_PUTS("errors=continue");
3027 	if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
3028 		SEQ_OPTS_PUTS("errors=panic");
3029 	if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
3030 		SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
3031 	if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
3032 		SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
3033 	if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
3034 		SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
3035 	if (sb->s_flags & SB_I_VERSION)
3036 		SEQ_OPTS_PUTS("i_version");
3037 	if (nodefs || sbi->s_stripe)
3038 		SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
3039 	if (nodefs || EXT4_MOUNT_DATA_FLAGS &
3040 			(sbi->s_mount_opt ^ def_mount_opt)) {
3041 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3042 			SEQ_OPTS_PUTS("data=journal");
3043 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3044 			SEQ_OPTS_PUTS("data=ordered");
3045 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
3046 			SEQ_OPTS_PUTS("data=writeback");
3047 	}
3048 	if (nodefs ||
3049 	    sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3050 		SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3051 			       sbi->s_inode_readahead_blks);
3052 
3053 	if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3054 		       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3055 		SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3056 	if (nodefs || sbi->s_max_dir_size_kb)
3057 		SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3058 	if (test_opt(sb, DATA_ERR_ABORT))
3059 		SEQ_OPTS_PUTS("data_err=abort");
3060 
3061 	fscrypt_show_test_dummy_encryption(seq, sep, sb);
3062 
3063 	if (sb->s_flags & SB_INLINECRYPT)
3064 		SEQ_OPTS_PUTS("inlinecrypt");
3065 
3066 	if (test_opt(sb, DAX_ALWAYS)) {
3067 		if (IS_EXT2_SB(sb))
3068 			SEQ_OPTS_PUTS("dax");
3069 		else
3070 			SEQ_OPTS_PUTS("dax=always");
3071 	} else if (test_opt2(sb, DAX_NEVER)) {
3072 		SEQ_OPTS_PUTS("dax=never");
3073 	} else if (test_opt2(sb, DAX_INODE)) {
3074 		SEQ_OPTS_PUTS("dax=inode");
3075 	}
3076 	ext4_show_quota_options(seq, sb);
3077 	return 0;
3078 }
3079 
3080 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3081 {
3082 	return _ext4_show_options(seq, root->d_sb, 0);
3083 }
3084 
3085 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3086 {
3087 	struct super_block *sb = seq->private;
3088 	int rc;
3089 
3090 	seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3091 	rc = _ext4_show_options(seq, sb, 1);
3092 	seq_puts(seq, "\n");
3093 	return rc;
3094 }
3095 
3096 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3097 			    int read_only)
3098 {
3099 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3100 	int err = 0;
3101 
3102 	if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3103 		ext4_msg(sb, KERN_ERR, "revision level too high, "
3104 			 "forcing read-only mode");
3105 		err = -EROFS;
3106 		goto done;
3107 	}
3108 	if (read_only)
3109 		goto done;
3110 	if (!(sbi->s_mount_state & EXT4_VALID_FS))
3111 		ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3112 			 "running e2fsck is recommended");
3113 	else if (sbi->s_mount_state & EXT4_ERROR_FS)
3114 		ext4_msg(sb, KERN_WARNING,
3115 			 "warning: mounting fs with errors, "
3116 			 "running e2fsck is recommended");
3117 	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3118 		 le16_to_cpu(es->s_mnt_count) >=
3119 		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3120 		ext4_msg(sb, KERN_WARNING,
3121 			 "warning: maximal mount count reached, "
3122 			 "running e2fsck is recommended");
3123 	else if (le32_to_cpu(es->s_checkinterval) &&
3124 		 (ext4_get_tstamp(es, s_lastcheck) +
3125 		  le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3126 		ext4_msg(sb, KERN_WARNING,
3127 			 "warning: checktime reached, "
3128 			 "running e2fsck is recommended");
3129 	if (!sbi->s_journal)
3130 		es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3131 	if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3132 		es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3133 	le16_add_cpu(&es->s_mnt_count, 1);
3134 	ext4_update_tstamp(es, s_mtime);
3135 	if (sbi->s_journal) {
3136 		ext4_set_feature_journal_needs_recovery(sb);
3137 		if (ext4_has_feature_orphan_file(sb))
3138 			ext4_set_feature_orphan_present(sb);
3139 	}
3140 
3141 	err = ext4_commit_super(sb);
3142 done:
3143 	if (test_opt(sb, DEBUG))
3144 		printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3145 				"bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3146 			sb->s_blocksize,
3147 			sbi->s_groups_count,
3148 			EXT4_BLOCKS_PER_GROUP(sb),
3149 			EXT4_INODES_PER_GROUP(sb),
3150 			sbi->s_mount_opt, sbi->s_mount_opt2);
3151 	return err;
3152 }
3153 
3154 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3155 {
3156 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3157 	struct flex_groups **old_groups, **new_groups;
3158 	int size, i, j;
3159 
3160 	if (!sbi->s_log_groups_per_flex)
3161 		return 0;
3162 
3163 	size = ext4_flex_group(sbi, ngroup - 1) + 1;
3164 	if (size <= sbi->s_flex_groups_allocated)
3165 		return 0;
3166 
3167 	new_groups = kvzalloc(roundup_pow_of_two(size *
3168 			      sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3169 	if (!new_groups) {
3170 		ext4_msg(sb, KERN_ERR,
3171 			 "not enough memory for %d flex group pointers", size);
3172 		return -ENOMEM;
3173 	}
3174 	for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3175 		new_groups[i] = kvzalloc(roundup_pow_of_two(
3176 					 sizeof(struct flex_groups)),
3177 					 GFP_KERNEL);
3178 		if (!new_groups[i]) {
3179 			for (j = sbi->s_flex_groups_allocated; j < i; j++)
3180 				kvfree(new_groups[j]);
3181 			kvfree(new_groups);
3182 			ext4_msg(sb, KERN_ERR,
3183 				 "not enough memory for %d flex groups", size);
3184 			return -ENOMEM;
3185 		}
3186 	}
3187 	rcu_read_lock();
3188 	old_groups = rcu_dereference(sbi->s_flex_groups);
3189 	if (old_groups)
3190 		memcpy(new_groups, old_groups,
3191 		       (sbi->s_flex_groups_allocated *
3192 			sizeof(struct flex_groups *)));
3193 	rcu_read_unlock();
3194 	rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3195 	sbi->s_flex_groups_allocated = size;
3196 	if (old_groups)
3197 		ext4_kvfree_array_rcu(old_groups);
3198 	return 0;
3199 }
3200 
3201 static int ext4_fill_flex_info(struct super_block *sb)
3202 {
3203 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3204 	struct ext4_group_desc *gdp = NULL;
3205 	struct flex_groups *fg;
3206 	ext4_group_t flex_group;
3207 	int i, err;
3208 
3209 	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3210 	if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3211 		sbi->s_log_groups_per_flex = 0;
3212 		return 1;
3213 	}
3214 
3215 	err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3216 	if (err)
3217 		goto failed;
3218 
3219 	for (i = 0; i < sbi->s_groups_count; i++) {
3220 		gdp = ext4_get_group_desc(sb, i, NULL);
3221 
3222 		flex_group = ext4_flex_group(sbi, i);
3223 		fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3224 		atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3225 		atomic64_add(ext4_free_group_clusters(sb, gdp),
3226 			     &fg->free_clusters);
3227 		atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3228 	}
3229 
3230 	return 1;
3231 failed:
3232 	return 0;
3233 }
3234 
3235 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3236 				   struct ext4_group_desc *gdp)
3237 {
3238 	int offset = offsetof(struct ext4_group_desc, bg_checksum);
3239 	__u16 crc = 0;
3240 	__le32 le_group = cpu_to_le32(block_group);
3241 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3242 
3243 	if (ext4_has_metadata_csum(sbi->s_sb)) {
3244 		/* Use new metadata_csum algorithm */
3245 		__u32 csum32;
3246 		__u16 dummy_csum = 0;
3247 
3248 		csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3249 				     sizeof(le_group));
3250 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3251 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3252 				     sizeof(dummy_csum));
3253 		offset += sizeof(dummy_csum);
3254 		if (offset < sbi->s_desc_size)
3255 			csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3256 					     sbi->s_desc_size - offset);
3257 
3258 		crc = csum32 & 0xFFFF;
3259 		goto out;
3260 	}
3261 
3262 	/* old crc16 code */
3263 	if (!ext4_has_feature_gdt_csum(sb))
3264 		return 0;
3265 
3266 	crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3267 	crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3268 	crc = crc16(crc, (__u8 *)gdp, offset);
3269 	offset += sizeof(gdp->bg_checksum); /* skip checksum */
3270 	/* for checksum of struct ext4_group_desc do the rest...*/
3271 	if (ext4_has_feature_64bit(sb) &&
3272 	    offset < le16_to_cpu(sbi->s_es->s_desc_size))
3273 		crc = crc16(crc, (__u8 *)gdp + offset,
3274 			    le16_to_cpu(sbi->s_es->s_desc_size) -
3275 				offset);
3276 
3277 out:
3278 	return cpu_to_le16(crc);
3279 }
3280 
3281 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3282 				struct ext4_group_desc *gdp)
3283 {
3284 	if (ext4_has_group_desc_csum(sb) &&
3285 	    (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3286 		return 0;
3287 
3288 	return 1;
3289 }
3290 
3291 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3292 			      struct ext4_group_desc *gdp)
3293 {
3294 	if (!ext4_has_group_desc_csum(sb))
3295 		return;
3296 	gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3297 }
3298 
3299 /* Called at mount-time, super-block is locked */
3300 static int ext4_check_descriptors(struct super_block *sb,
3301 				  ext4_fsblk_t sb_block,
3302 				  ext4_group_t *first_not_zeroed)
3303 {
3304 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3305 	ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3306 	ext4_fsblk_t last_block;
3307 	ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3308 	ext4_fsblk_t block_bitmap;
3309 	ext4_fsblk_t inode_bitmap;
3310 	ext4_fsblk_t inode_table;
3311 	int flexbg_flag = 0;
3312 	ext4_group_t i, grp = sbi->s_groups_count;
3313 
3314 	if (ext4_has_feature_flex_bg(sb))
3315 		flexbg_flag = 1;
3316 
3317 	ext4_debug("Checking group descriptors");
3318 
3319 	for (i = 0; i < sbi->s_groups_count; i++) {
3320 		struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3321 
3322 		if (i == sbi->s_groups_count - 1 || flexbg_flag)
3323 			last_block = ext4_blocks_count(sbi->s_es) - 1;
3324 		else
3325 			last_block = first_block +
3326 				(EXT4_BLOCKS_PER_GROUP(sb) - 1);
3327 
3328 		if ((grp == sbi->s_groups_count) &&
3329 		   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3330 			grp = i;
3331 
3332 		block_bitmap = ext4_block_bitmap(sb, gdp);
3333 		if (block_bitmap == sb_block) {
3334 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3335 				 "Block bitmap for group %u overlaps "
3336 				 "superblock", i);
3337 			if (!sb_rdonly(sb))
3338 				return 0;
3339 		}
3340 		if (block_bitmap >= sb_block + 1 &&
3341 		    block_bitmap <= last_bg_block) {
3342 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3343 				 "Block bitmap for group %u overlaps "
3344 				 "block group descriptors", i);
3345 			if (!sb_rdonly(sb))
3346 				return 0;
3347 		}
3348 		if (block_bitmap < first_block || block_bitmap > last_block) {
3349 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3350 			       "Block bitmap for group %u not in group "
3351 			       "(block %llu)!", i, block_bitmap);
3352 			return 0;
3353 		}
3354 		inode_bitmap = ext4_inode_bitmap(sb, gdp);
3355 		if (inode_bitmap == sb_block) {
3356 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3357 				 "Inode bitmap for group %u overlaps "
3358 				 "superblock", i);
3359 			if (!sb_rdonly(sb))
3360 				return 0;
3361 		}
3362 		if (inode_bitmap >= sb_block + 1 &&
3363 		    inode_bitmap <= last_bg_block) {
3364 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3365 				 "Inode bitmap for group %u overlaps "
3366 				 "block group descriptors", i);
3367 			if (!sb_rdonly(sb))
3368 				return 0;
3369 		}
3370 		if (inode_bitmap < first_block || inode_bitmap > last_block) {
3371 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3372 			       "Inode bitmap for group %u not in group "
3373 			       "(block %llu)!", i, inode_bitmap);
3374 			return 0;
3375 		}
3376 		inode_table = ext4_inode_table(sb, gdp);
3377 		if (inode_table == sb_block) {
3378 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3379 				 "Inode table for group %u overlaps "
3380 				 "superblock", i);
3381 			if (!sb_rdonly(sb))
3382 				return 0;
3383 		}
3384 		if (inode_table >= sb_block + 1 &&
3385 		    inode_table <= last_bg_block) {
3386 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3387 				 "Inode table for group %u overlaps "
3388 				 "block group descriptors", i);
3389 			if (!sb_rdonly(sb))
3390 				return 0;
3391 		}
3392 		if (inode_table < first_block ||
3393 		    inode_table + sbi->s_itb_per_group - 1 > last_block) {
3394 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3395 			       "Inode table for group %u not in group "
3396 			       "(block %llu)!", i, inode_table);
3397 			return 0;
3398 		}
3399 		ext4_lock_group(sb, i);
3400 		if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3401 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3402 				 "Checksum for group %u failed (%u!=%u)",
3403 				 i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3404 				     gdp)), le16_to_cpu(gdp->bg_checksum));
3405 			if (!sb_rdonly(sb)) {
3406 				ext4_unlock_group(sb, i);
3407 				return 0;
3408 			}
3409 		}
3410 		ext4_unlock_group(sb, i);
3411 		if (!flexbg_flag)
3412 			first_block += EXT4_BLOCKS_PER_GROUP(sb);
3413 	}
3414 	if (NULL != first_not_zeroed)
3415 		*first_not_zeroed = grp;
3416 	return 1;
3417 }
3418 
3419 /*
3420  * Maximal extent format file size.
3421  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3422  * extent format containers, within a sector_t, and within i_blocks
3423  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3424  * so that won't be a limiting factor.
3425  *
3426  * However there is other limiting factor. We do store extents in the form
3427  * of starting block and length, hence the resulting length of the extent
3428  * covering maximum file size must fit into on-disk format containers as
3429  * well. Given that length is always by 1 unit bigger than max unit (because
3430  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3431  *
3432  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3433  */
3434 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3435 {
3436 	loff_t res;
3437 	loff_t upper_limit = MAX_LFS_FILESIZE;
3438 
3439 	BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3440 
3441 	if (!has_huge_files) {
3442 		upper_limit = (1LL << 32) - 1;
3443 
3444 		/* total blocks in file system block size */
3445 		upper_limit >>= (blkbits - 9);
3446 		upper_limit <<= blkbits;
3447 	}
3448 
3449 	/*
3450 	 * 32-bit extent-start container, ee_block. We lower the maxbytes
3451 	 * by one fs block, so ee_len can cover the extent of maximum file
3452 	 * size
3453 	 */
3454 	res = (1LL << 32) - 1;
3455 	res <<= blkbits;
3456 
3457 	/* Sanity check against vm- & vfs- imposed limits */
3458 	if (res > upper_limit)
3459 		res = upper_limit;
3460 
3461 	return res;
3462 }
3463 
3464 /*
3465  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3466  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3467  * We need to be 1 filesystem block less than the 2^48 sector limit.
3468  */
3469 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3470 {
3471 	unsigned long long upper_limit, res = EXT4_NDIR_BLOCKS;
3472 	int meta_blocks;
3473 
3474 	/*
3475 	 * This is calculated to be the largest file size for a dense, block
3476 	 * mapped file such that the file's total number of 512-byte sectors,
3477 	 * including data and all indirect blocks, does not exceed (2^48 - 1).
3478 	 *
3479 	 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3480 	 * number of 512-byte sectors of the file.
3481 	 */
3482 	if (!has_huge_files) {
3483 		/*
3484 		 * !has_huge_files or implies that the inode i_block field
3485 		 * represents total file blocks in 2^32 512-byte sectors ==
3486 		 * size of vfs inode i_blocks * 8
3487 		 */
3488 		upper_limit = (1LL << 32) - 1;
3489 
3490 		/* total blocks in file system block size */
3491 		upper_limit >>= (bits - 9);
3492 
3493 	} else {
3494 		/*
3495 		 * We use 48 bit ext4_inode i_blocks
3496 		 * With EXT4_HUGE_FILE_FL set the i_blocks
3497 		 * represent total number of blocks in
3498 		 * file system block size
3499 		 */
3500 		upper_limit = (1LL << 48) - 1;
3501 
3502 	}
3503 
3504 	/* indirect blocks */
3505 	meta_blocks = 1;
3506 	/* double indirect blocks */
3507 	meta_blocks += 1 + (1LL << (bits-2));
3508 	/* tripple indirect blocks */
3509 	meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3510 
3511 	upper_limit -= meta_blocks;
3512 	upper_limit <<= bits;
3513 
3514 	res += 1LL << (bits-2);
3515 	res += 1LL << (2*(bits-2));
3516 	res += 1LL << (3*(bits-2));
3517 	res <<= bits;
3518 	if (res > upper_limit)
3519 		res = upper_limit;
3520 
3521 	if (res > MAX_LFS_FILESIZE)
3522 		res = MAX_LFS_FILESIZE;
3523 
3524 	return (loff_t)res;
3525 }
3526 
3527 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3528 				   ext4_fsblk_t logical_sb_block, int nr)
3529 {
3530 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3531 	ext4_group_t bg, first_meta_bg;
3532 	int has_super = 0;
3533 
3534 	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3535 
3536 	if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3537 		return logical_sb_block + nr + 1;
3538 	bg = sbi->s_desc_per_block * nr;
3539 	if (ext4_bg_has_super(sb, bg))
3540 		has_super = 1;
3541 
3542 	/*
3543 	 * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3544 	 * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3545 	 * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3546 	 * compensate.
3547 	 */
3548 	if (sb->s_blocksize == 1024 && nr == 0 &&
3549 	    le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3550 		has_super++;
3551 
3552 	return (has_super + ext4_group_first_block_no(sb, bg));
3553 }
3554 
3555 /**
3556  * ext4_get_stripe_size: Get the stripe size.
3557  * @sbi: In memory super block info
3558  *
3559  * If we have specified it via mount option, then
3560  * use the mount option value. If the value specified at mount time is
3561  * greater than the blocks per group use the super block value.
3562  * If the super block value is greater than blocks per group return 0.
3563  * Allocator needs it be less than blocks per group.
3564  *
3565  */
3566 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3567 {
3568 	unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3569 	unsigned long stripe_width =
3570 			le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3571 	int ret;
3572 
3573 	if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3574 		ret = sbi->s_stripe;
3575 	else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3576 		ret = stripe_width;
3577 	else if (stride && stride <= sbi->s_blocks_per_group)
3578 		ret = stride;
3579 	else
3580 		ret = 0;
3581 
3582 	/*
3583 	 * If the stripe width is 1, this makes no sense and
3584 	 * we set it to 0 to turn off stripe handling code.
3585 	 */
3586 	if (ret <= 1)
3587 		ret = 0;
3588 
3589 	return ret;
3590 }
3591 
3592 /*
3593  * Check whether this filesystem can be mounted based on
3594  * the features present and the RDONLY/RDWR mount requested.
3595  * Returns 1 if this filesystem can be mounted as requested,
3596  * 0 if it cannot be.
3597  */
3598 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3599 {
3600 	if (ext4_has_unknown_ext4_incompat_features(sb)) {
3601 		ext4_msg(sb, KERN_ERR,
3602 			"Couldn't mount because of "
3603 			"unsupported optional features (%x)",
3604 			(le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3605 			~EXT4_FEATURE_INCOMPAT_SUPP));
3606 		return 0;
3607 	}
3608 
3609 #ifndef CONFIG_UNICODE
3610 	if (ext4_has_feature_casefold(sb)) {
3611 		ext4_msg(sb, KERN_ERR,
3612 			 "Filesystem with casefold feature cannot be "
3613 			 "mounted without CONFIG_UNICODE");
3614 		return 0;
3615 	}
3616 #endif
3617 
3618 	if (readonly)
3619 		return 1;
3620 
3621 	if (ext4_has_feature_readonly(sb)) {
3622 		ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3623 		sb->s_flags |= SB_RDONLY;
3624 		return 1;
3625 	}
3626 
3627 	/* Check that feature set is OK for a read-write mount */
3628 	if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3629 		ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3630 			 "unsupported optional features (%x)",
3631 			 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3632 				~EXT4_FEATURE_RO_COMPAT_SUPP));
3633 		return 0;
3634 	}
3635 	if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3636 		ext4_msg(sb, KERN_ERR,
3637 			 "Can't support bigalloc feature without "
3638 			 "extents feature\n");
3639 		return 0;
3640 	}
3641 
3642 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3643 	if (!readonly && (ext4_has_feature_quota(sb) ||
3644 			  ext4_has_feature_project(sb))) {
3645 		ext4_msg(sb, KERN_ERR,
3646 			 "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3647 		return 0;
3648 	}
3649 #endif  /* CONFIG_QUOTA */
3650 	return 1;
3651 }
3652 
3653 /*
3654  * This function is called once a day if we have errors logged
3655  * on the file system
3656  */
3657 static void print_daily_error_info(struct timer_list *t)
3658 {
3659 	struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3660 	struct super_block *sb = sbi->s_sb;
3661 	struct ext4_super_block *es = sbi->s_es;
3662 
3663 	if (es->s_error_count)
3664 		/* fsck newer than v1.41.13 is needed to clean this condition. */
3665 		ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3666 			 le32_to_cpu(es->s_error_count));
3667 	if (es->s_first_error_time) {
3668 		printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3669 		       sb->s_id,
3670 		       ext4_get_tstamp(es, s_first_error_time),
3671 		       (int) sizeof(es->s_first_error_func),
3672 		       es->s_first_error_func,
3673 		       le32_to_cpu(es->s_first_error_line));
3674 		if (es->s_first_error_ino)
3675 			printk(KERN_CONT ": inode %u",
3676 			       le32_to_cpu(es->s_first_error_ino));
3677 		if (es->s_first_error_block)
3678 			printk(KERN_CONT ": block %llu", (unsigned long long)
3679 			       le64_to_cpu(es->s_first_error_block));
3680 		printk(KERN_CONT "\n");
3681 	}
3682 	if (es->s_last_error_time) {
3683 		printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3684 		       sb->s_id,
3685 		       ext4_get_tstamp(es, s_last_error_time),
3686 		       (int) sizeof(es->s_last_error_func),
3687 		       es->s_last_error_func,
3688 		       le32_to_cpu(es->s_last_error_line));
3689 		if (es->s_last_error_ino)
3690 			printk(KERN_CONT ": inode %u",
3691 			       le32_to_cpu(es->s_last_error_ino));
3692 		if (es->s_last_error_block)
3693 			printk(KERN_CONT ": block %llu", (unsigned long long)
3694 			       le64_to_cpu(es->s_last_error_block));
3695 		printk(KERN_CONT "\n");
3696 	}
3697 	mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3698 }
3699 
3700 /* Find next suitable group and run ext4_init_inode_table */
3701 static int ext4_run_li_request(struct ext4_li_request *elr)
3702 {
3703 	struct ext4_group_desc *gdp = NULL;
3704 	struct super_block *sb = elr->lr_super;
3705 	ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3706 	ext4_group_t group = elr->lr_next_group;
3707 	unsigned int prefetch_ios = 0;
3708 	int ret = 0;
3709 	u64 start_time;
3710 
3711 	if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3712 		elr->lr_next_group = ext4_mb_prefetch(sb, group,
3713 				EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3714 		if (prefetch_ios)
3715 			ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3716 					      prefetch_ios);
3717 		trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3718 					    prefetch_ios);
3719 		if (group >= elr->lr_next_group) {
3720 			ret = 1;
3721 			if (elr->lr_first_not_zeroed != ngroups &&
3722 			    !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3723 				elr->lr_next_group = elr->lr_first_not_zeroed;
3724 				elr->lr_mode = EXT4_LI_MODE_ITABLE;
3725 				ret = 0;
3726 			}
3727 		}
3728 		return ret;
3729 	}
3730 
3731 	for (; group < ngroups; group++) {
3732 		gdp = ext4_get_group_desc(sb, group, NULL);
3733 		if (!gdp) {
3734 			ret = 1;
3735 			break;
3736 		}
3737 
3738 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3739 			break;
3740 	}
3741 
3742 	if (group >= ngroups)
3743 		ret = 1;
3744 
3745 	if (!ret) {
3746 		start_time = ktime_get_real_ns();
3747 		ret = ext4_init_inode_table(sb, group,
3748 					    elr->lr_timeout ? 0 : 1);
3749 		trace_ext4_lazy_itable_init(sb, group);
3750 		if (elr->lr_timeout == 0) {
3751 			elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3752 				EXT4_SB(elr->lr_super)->s_li_wait_mult);
3753 		}
3754 		elr->lr_next_sched = jiffies + elr->lr_timeout;
3755 		elr->lr_next_group = group + 1;
3756 	}
3757 	return ret;
3758 }
3759 
3760 /*
3761  * Remove lr_request from the list_request and free the
3762  * request structure. Should be called with li_list_mtx held
3763  */
3764 static void ext4_remove_li_request(struct ext4_li_request *elr)
3765 {
3766 	if (!elr)
3767 		return;
3768 
3769 	list_del(&elr->lr_request);
3770 	EXT4_SB(elr->lr_super)->s_li_request = NULL;
3771 	kfree(elr);
3772 }
3773 
3774 static void ext4_unregister_li_request(struct super_block *sb)
3775 {
3776 	mutex_lock(&ext4_li_mtx);
3777 	if (!ext4_li_info) {
3778 		mutex_unlock(&ext4_li_mtx);
3779 		return;
3780 	}
3781 
3782 	mutex_lock(&ext4_li_info->li_list_mtx);
3783 	ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3784 	mutex_unlock(&ext4_li_info->li_list_mtx);
3785 	mutex_unlock(&ext4_li_mtx);
3786 }
3787 
3788 static struct task_struct *ext4_lazyinit_task;
3789 
3790 /*
3791  * This is the function where ext4lazyinit thread lives. It walks
3792  * through the request list searching for next scheduled filesystem.
3793  * When such a fs is found, run the lazy initialization request
3794  * (ext4_rn_li_request) and keep track of the time spend in this
3795  * function. Based on that time we compute next schedule time of
3796  * the request. When walking through the list is complete, compute
3797  * next waking time and put itself into sleep.
3798  */
3799 static int ext4_lazyinit_thread(void *arg)
3800 {
3801 	struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3802 	struct list_head *pos, *n;
3803 	struct ext4_li_request *elr;
3804 	unsigned long next_wakeup, cur;
3805 
3806 	BUG_ON(NULL == eli);
3807 
3808 cont_thread:
3809 	while (true) {
3810 		next_wakeup = MAX_JIFFY_OFFSET;
3811 
3812 		mutex_lock(&eli->li_list_mtx);
3813 		if (list_empty(&eli->li_request_list)) {
3814 			mutex_unlock(&eli->li_list_mtx);
3815 			goto exit_thread;
3816 		}
3817 		list_for_each_safe(pos, n, &eli->li_request_list) {
3818 			int err = 0;
3819 			int progress = 0;
3820 			elr = list_entry(pos, struct ext4_li_request,
3821 					 lr_request);
3822 
3823 			if (time_before(jiffies, elr->lr_next_sched)) {
3824 				if (time_before(elr->lr_next_sched, next_wakeup))
3825 					next_wakeup = elr->lr_next_sched;
3826 				continue;
3827 			}
3828 			if (down_read_trylock(&elr->lr_super->s_umount)) {
3829 				if (sb_start_write_trylock(elr->lr_super)) {
3830 					progress = 1;
3831 					/*
3832 					 * We hold sb->s_umount, sb can not
3833 					 * be removed from the list, it is
3834 					 * now safe to drop li_list_mtx
3835 					 */
3836 					mutex_unlock(&eli->li_list_mtx);
3837 					err = ext4_run_li_request(elr);
3838 					sb_end_write(elr->lr_super);
3839 					mutex_lock(&eli->li_list_mtx);
3840 					n = pos->next;
3841 				}
3842 				up_read((&elr->lr_super->s_umount));
3843 			}
3844 			/* error, remove the lazy_init job */
3845 			if (err) {
3846 				ext4_remove_li_request(elr);
3847 				continue;
3848 			}
3849 			if (!progress) {
3850 				elr->lr_next_sched = jiffies +
3851 					(prandom_u32()
3852 					 % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3853 			}
3854 			if (time_before(elr->lr_next_sched, next_wakeup))
3855 				next_wakeup = elr->lr_next_sched;
3856 		}
3857 		mutex_unlock(&eli->li_list_mtx);
3858 
3859 		try_to_freeze();
3860 
3861 		cur = jiffies;
3862 		if ((time_after_eq(cur, next_wakeup)) ||
3863 		    (MAX_JIFFY_OFFSET == next_wakeup)) {
3864 			cond_resched();
3865 			continue;
3866 		}
3867 
3868 		schedule_timeout_interruptible(next_wakeup - cur);
3869 
3870 		if (kthread_should_stop()) {
3871 			ext4_clear_request_list();
3872 			goto exit_thread;
3873 		}
3874 	}
3875 
3876 exit_thread:
3877 	/*
3878 	 * It looks like the request list is empty, but we need
3879 	 * to check it under the li_list_mtx lock, to prevent any
3880 	 * additions into it, and of course we should lock ext4_li_mtx
3881 	 * to atomically free the list and ext4_li_info, because at
3882 	 * this point another ext4 filesystem could be registering
3883 	 * new one.
3884 	 */
3885 	mutex_lock(&ext4_li_mtx);
3886 	mutex_lock(&eli->li_list_mtx);
3887 	if (!list_empty(&eli->li_request_list)) {
3888 		mutex_unlock(&eli->li_list_mtx);
3889 		mutex_unlock(&ext4_li_mtx);
3890 		goto cont_thread;
3891 	}
3892 	mutex_unlock(&eli->li_list_mtx);
3893 	kfree(ext4_li_info);
3894 	ext4_li_info = NULL;
3895 	mutex_unlock(&ext4_li_mtx);
3896 
3897 	return 0;
3898 }
3899 
3900 static void ext4_clear_request_list(void)
3901 {
3902 	struct list_head *pos, *n;
3903 	struct ext4_li_request *elr;
3904 
3905 	mutex_lock(&ext4_li_info->li_list_mtx);
3906 	list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3907 		elr = list_entry(pos, struct ext4_li_request,
3908 				 lr_request);
3909 		ext4_remove_li_request(elr);
3910 	}
3911 	mutex_unlock(&ext4_li_info->li_list_mtx);
3912 }
3913 
3914 static int ext4_run_lazyinit_thread(void)
3915 {
3916 	ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3917 					 ext4_li_info, "ext4lazyinit");
3918 	if (IS_ERR(ext4_lazyinit_task)) {
3919 		int err = PTR_ERR(ext4_lazyinit_task);
3920 		ext4_clear_request_list();
3921 		kfree(ext4_li_info);
3922 		ext4_li_info = NULL;
3923 		printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3924 				 "initialization thread\n",
3925 				 err);
3926 		return err;
3927 	}
3928 	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3929 	return 0;
3930 }
3931 
3932 /*
3933  * Check whether it make sense to run itable init. thread or not.
3934  * If there is at least one uninitialized inode table, return
3935  * corresponding group number, else the loop goes through all
3936  * groups and return total number of groups.
3937  */
3938 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3939 {
3940 	ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3941 	struct ext4_group_desc *gdp = NULL;
3942 
3943 	if (!ext4_has_group_desc_csum(sb))
3944 		return ngroups;
3945 
3946 	for (group = 0; group < ngroups; group++) {
3947 		gdp = ext4_get_group_desc(sb, group, NULL);
3948 		if (!gdp)
3949 			continue;
3950 
3951 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3952 			break;
3953 	}
3954 
3955 	return group;
3956 }
3957 
3958 static int ext4_li_info_new(void)
3959 {
3960 	struct ext4_lazy_init *eli = NULL;
3961 
3962 	eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3963 	if (!eli)
3964 		return -ENOMEM;
3965 
3966 	INIT_LIST_HEAD(&eli->li_request_list);
3967 	mutex_init(&eli->li_list_mtx);
3968 
3969 	eli->li_state |= EXT4_LAZYINIT_QUIT;
3970 
3971 	ext4_li_info = eli;
3972 
3973 	return 0;
3974 }
3975 
3976 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3977 					    ext4_group_t start)
3978 {
3979 	struct ext4_li_request *elr;
3980 
3981 	elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3982 	if (!elr)
3983 		return NULL;
3984 
3985 	elr->lr_super = sb;
3986 	elr->lr_first_not_zeroed = start;
3987 	if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3988 		elr->lr_mode = EXT4_LI_MODE_ITABLE;
3989 		elr->lr_next_group = start;
3990 	} else {
3991 		elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3992 	}
3993 
3994 	/*
3995 	 * Randomize first schedule time of the request to
3996 	 * spread the inode table initialization requests
3997 	 * better.
3998 	 */
3999 	elr->lr_next_sched = jiffies + (prandom_u32() %
4000 				(EXT4_DEF_LI_MAX_START_DELAY * HZ));
4001 	return elr;
4002 }
4003 
4004 int ext4_register_li_request(struct super_block *sb,
4005 			     ext4_group_t first_not_zeroed)
4006 {
4007 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4008 	struct ext4_li_request *elr = NULL;
4009 	ext4_group_t ngroups = sbi->s_groups_count;
4010 	int ret = 0;
4011 
4012 	mutex_lock(&ext4_li_mtx);
4013 	if (sbi->s_li_request != NULL) {
4014 		/*
4015 		 * Reset timeout so it can be computed again, because
4016 		 * s_li_wait_mult might have changed.
4017 		 */
4018 		sbi->s_li_request->lr_timeout = 0;
4019 		goto out;
4020 	}
4021 
4022 	if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4023 	    (first_not_zeroed == ngroups || sb_rdonly(sb) ||
4024 	     !test_opt(sb, INIT_INODE_TABLE)))
4025 		goto out;
4026 
4027 	elr = ext4_li_request_new(sb, first_not_zeroed);
4028 	if (!elr) {
4029 		ret = -ENOMEM;
4030 		goto out;
4031 	}
4032 
4033 	if (NULL == ext4_li_info) {
4034 		ret = ext4_li_info_new();
4035 		if (ret)
4036 			goto out;
4037 	}
4038 
4039 	mutex_lock(&ext4_li_info->li_list_mtx);
4040 	list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4041 	mutex_unlock(&ext4_li_info->li_list_mtx);
4042 
4043 	sbi->s_li_request = elr;
4044 	/*
4045 	 * set elr to NULL here since it has been inserted to
4046 	 * the request_list and the removal and free of it is
4047 	 * handled by ext4_clear_request_list from now on.
4048 	 */
4049 	elr = NULL;
4050 
4051 	if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4052 		ret = ext4_run_lazyinit_thread();
4053 		if (ret)
4054 			goto out;
4055 	}
4056 out:
4057 	mutex_unlock(&ext4_li_mtx);
4058 	if (ret)
4059 		kfree(elr);
4060 	return ret;
4061 }
4062 
4063 /*
4064  * We do not need to lock anything since this is called on
4065  * module unload.
4066  */
4067 static void ext4_destroy_lazyinit_thread(void)
4068 {
4069 	/*
4070 	 * If thread exited earlier
4071 	 * there's nothing to be done.
4072 	 */
4073 	if (!ext4_li_info || !ext4_lazyinit_task)
4074 		return;
4075 
4076 	kthread_stop(ext4_lazyinit_task);
4077 }
4078 
4079 static int set_journal_csum_feature_set(struct super_block *sb)
4080 {
4081 	int ret = 1;
4082 	int compat, incompat;
4083 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4084 
4085 	if (ext4_has_metadata_csum(sb)) {
4086 		/* journal checksum v3 */
4087 		compat = 0;
4088 		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4089 	} else {
4090 		/* journal checksum v1 */
4091 		compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4092 		incompat = 0;
4093 	}
4094 
4095 	jbd2_journal_clear_features(sbi->s_journal,
4096 			JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4097 			JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4098 			JBD2_FEATURE_INCOMPAT_CSUM_V2);
4099 	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4100 		ret = jbd2_journal_set_features(sbi->s_journal,
4101 				compat, 0,
4102 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4103 				incompat);
4104 	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4105 		ret = jbd2_journal_set_features(sbi->s_journal,
4106 				compat, 0,
4107 				incompat);
4108 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4109 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4110 	} else {
4111 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4112 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4113 	}
4114 
4115 	return ret;
4116 }
4117 
4118 /*
4119  * Note: calculating the overhead so we can be compatible with
4120  * historical BSD practice is quite difficult in the face of
4121  * clusters/bigalloc.  This is because multiple metadata blocks from
4122  * different block group can end up in the same allocation cluster.
4123  * Calculating the exact overhead in the face of clustered allocation
4124  * requires either O(all block bitmaps) in memory or O(number of block
4125  * groups**2) in time.  We will still calculate the superblock for
4126  * older file systems --- and if we come across with a bigalloc file
4127  * system with zero in s_overhead_clusters the estimate will be close to
4128  * correct especially for very large cluster sizes --- but for newer
4129  * file systems, it's better to calculate this figure once at mkfs
4130  * time, and store it in the superblock.  If the superblock value is
4131  * present (even for non-bigalloc file systems), we will use it.
4132  */
4133 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4134 			  char *buf)
4135 {
4136 	struct ext4_sb_info	*sbi = EXT4_SB(sb);
4137 	struct ext4_group_desc	*gdp;
4138 	ext4_fsblk_t		first_block, last_block, b;
4139 	ext4_group_t		i, ngroups = ext4_get_groups_count(sb);
4140 	int			s, j, count = 0;
4141 
4142 	if (!ext4_has_feature_bigalloc(sb))
4143 		return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
4144 			sbi->s_itb_per_group + 2);
4145 
4146 	first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4147 		(grp * EXT4_BLOCKS_PER_GROUP(sb));
4148 	last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4149 	for (i = 0; i < ngroups; i++) {
4150 		gdp = ext4_get_group_desc(sb, i, NULL);
4151 		b = ext4_block_bitmap(sb, gdp);
4152 		if (b >= first_block && b <= last_block) {
4153 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4154 			count++;
4155 		}
4156 		b = ext4_inode_bitmap(sb, gdp);
4157 		if (b >= first_block && b <= last_block) {
4158 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4159 			count++;
4160 		}
4161 		b = ext4_inode_table(sb, gdp);
4162 		if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4163 			for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4164 				int c = EXT4_B2C(sbi, b - first_block);
4165 				ext4_set_bit(c, buf);
4166 				count++;
4167 			}
4168 		if (i != grp)
4169 			continue;
4170 		s = 0;
4171 		if (ext4_bg_has_super(sb, grp)) {
4172 			ext4_set_bit(s++, buf);
4173 			count++;
4174 		}
4175 		j = ext4_bg_num_gdb(sb, grp);
4176 		if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4177 			ext4_error(sb, "Invalid number of block group "
4178 				   "descriptor blocks: %d", j);
4179 			j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4180 		}
4181 		count += j;
4182 		for (; j > 0; j--)
4183 			ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4184 	}
4185 	if (!count)
4186 		return 0;
4187 	return EXT4_CLUSTERS_PER_GROUP(sb) -
4188 		ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4189 }
4190 
4191 /*
4192  * Compute the overhead and stash it in sbi->s_overhead
4193  */
4194 int ext4_calculate_overhead(struct super_block *sb)
4195 {
4196 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4197 	struct ext4_super_block *es = sbi->s_es;
4198 	struct inode *j_inode;
4199 	unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4200 	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4201 	ext4_fsblk_t overhead = 0;
4202 	char *buf = (char *) get_zeroed_page(GFP_NOFS);
4203 
4204 	if (!buf)
4205 		return -ENOMEM;
4206 
4207 	/*
4208 	 * Compute the overhead (FS structures).  This is constant
4209 	 * for a given filesystem unless the number of block groups
4210 	 * changes so we cache the previous value until it does.
4211 	 */
4212 
4213 	/*
4214 	 * All of the blocks before first_data_block are overhead
4215 	 */
4216 	overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4217 
4218 	/*
4219 	 * Add the overhead found in each block group
4220 	 */
4221 	for (i = 0; i < ngroups; i++) {
4222 		int blks;
4223 
4224 		blks = count_overhead(sb, i, buf);
4225 		overhead += blks;
4226 		if (blks)
4227 			memset(buf, 0, PAGE_SIZE);
4228 		cond_resched();
4229 	}
4230 
4231 	/*
4232 	 * Add the internal journal blocks whether the journal has been
4233 	 * loaded or not
4234 	 */
4235 	if (sbi->s_journal && !sbi->s_journal_bdev)
4236 		overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4237 	else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4238 		/* j_inum for internal journal is non-zero */
4239 		j_inode = ext4_get_journal_inode(sb, j_inum);
4240 		if (j_inode) {
4241 			j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4242 			overhead += EXT4_NUM_B2C(sbi, j_blocks);
4243 			iput(j_inode);
4244 		} else {
4245 			ext4_msg(sb, KERN_ERR, "can't get journal size");
4246 		}
4247 	}
4248 	sbi->s_overhead = overhead;
4249 	smp_wmb();
4250 	free_page((unsigned long) buf);
4251 	return 0;
4252 }
4253 
4254 static void ext4_set_resv_clusters(struct super_block *sb)
4255 {
4256 	ext4_fsblk_t resv_clusters;
4257 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4258 
4259 	/*
4260 	 * There's no need to reserve anything when we aren't using extents.
4261 	 * The space estimates are exact, there are no unwritten extents,
4262 	 * hole punching doesn't need new metadata... This is needed especially
4263 	 * to keep ext2/3 backward compatibility.
4264 	 */
4265 	if (!ext4_has_feature_extents(sb))
4266 		return;
4267 	/*
4268 	 * By default we reserve 2% or 4096 clusters, whichever is smaller.
4269 	 * This should cover the situations where we can not afford to run
4270 	 * out of space like for example punch hole, or converting
4271 	 * unwritten extents in delalloc path. In most cases such
4272 	 * allocation would require 1, or 2 blocks, higher numbers are
4273 	 * very rare.
4274 	 */
4275 	resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4276 			 sbi->s_cluster_bits);
4277 
4278 	do_div(resv_clusters, 50);
4279 	resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4280 
4281 	atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4282 }
4283 
4284 static const char *ext4_quota_mode(struct super_block *sb)
4285 {
4286 #ifdef CONFIG_QUOTA
4287 	if (!ext4_quota_capable(sb))
4288 		return "none";
4289 
4290 	if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4291 		return "journalled";
4292 	else
4293 		return "writeback";
4294 #else
4295 	return "disabled";
4296 #endif
4297 }
4298 
4299 static void ext4_setup_csum_trigger(struct super_block *sb,
4300 				    enum ext4_journal_trigger_type type,
4301 				    void (*trigger)(
4302 					struct jbd2_buffer_trigger_type *type,
4303 					struct buffer_head *bh,
4304 					void *mapped_data,
4305 					size_t size))
4306 {
4307 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4308 
4309 	sbi->s_journal_triggers[type].sb = sb;
4310 	sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4311 }
4312 
4313 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4314 {
4315 	if (!sbi)
4316 		return;
4317 
4318 	kfree(sbi->s_blockgroup_lock);
4319 	fs_put_dax(sbi->s_daxdev);
4320 	kfree(sbi);
4321 }
4322 
4323 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4324 {
4325 	struct ext4_sb_info *sbi;
4326 
4327 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4328 	if (!sbi)
4329 		return NULL;
4330 
4331 	sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off);
4332 
4333 	sbi->s_blockgroup_lock =
4334 		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4335 
4336 	if (!sbi->s_blockgroup_lock)
4337 		goto err_out;
4338 
4339 	sb->s_fs_info = sbi;
4340 	sbi->s_sb = sb;
4341 	return sbi;
4342 err_out:
4343 	fs_put_dax(sbi->s_daxdev);
4344 	kfree(sbi);
4345 	return NULL;
4346 }
4347 
4348 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
4349 {
4350 	struct buffer_head *bh, **group_desc;
4351 	struct ext4_super_block *es = NULL;
4352 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4353 	struct flex_groups **flex_groups;
4354 	ext4_fsblk_t block;
4355 	ext4_fsblk_t logical_sb_block;
4356 	unsigned long offset = 0;
4357 	unsigned long def_mount_opts;
4358 	struct inode *root;
4359 	int ret = -ENOMEM;
4360 	int blocksize, clustersize;
4361 	unsigned int db_count;
4362 	unsigned int i;
4363 	int needs_recovery, has_huge_files;
4364 	__u64 blocks_count;
4365 	int err = 0;
4366 	ext4_group_t first_not_zeroed;
4367 	struct ext4_fs_context *ctx = fc->fs_private;
4368 	int silent = fc->sb_flags & SB_SILENT;
4369 
4370 	/* Set defaults for the variables that will be set during parsing */
4371 	ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4372 	ctx->mb_optimize_scan = DEFAULT_MB_OPTIMIZE_SCAN;
4373 
4374 	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4375 	sbi->s_sectors_written_start =
4376 		part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
4377 
4378 	/* -EINVAL is default */
4379 	ret = -EINVAL;
4380 	blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4381 	if (!blocksize) {
4382 		ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4383 		goto out_fail;
4384 	}
4385 
4386 	/*
4387 	 * The ext4 superblock will not be buffer aligned for other than 1kB
4388 	 * block sizes.  We need to calculate the offset from buffer start.
4389 	 */
4390 	if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4391 		logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4392 		offset = do_div(logical_sb_block, blocksize);
4393 	} else {
4394 		logical_sb_block = sbi->s_sb_block;
4395 	}
4396 
4397 	bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4398 	if (IS_ERR(bh)) {
4399 		ext4_msg(sb, KERN_ERR, "unable to read superblock");
4400 		ret = PTR_ERR(bh);
4401 		goto out_fail;
4402 	}
4403 	/*
4404 	 * Note: s_es must be initialized as soon as possible because
4405 	 *       some ext4 macro-instructions depend on its value
4406 	 */
4407 	es = (struct ext4_super_block *) (bh->b_data + offset);
4408 	sbi->s_es = es;
4409 	sb->s_magic = le16_to_cpu(es->s_magic);
4410 	if (sb->s_magic != EXT4_SUPER_MAGIC)
4411 		goto cantfind_ext4;
4412 	sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4413 
4414 	/* Warn if metadata_csum and gdt_csum are both set. */
4415 	if (ext4_has_feature_metadata_csum(sb) &&
4416 	    ext4_has_feature_gdt_csum(sb))
4417 		ext4_warning(sb, "metadata_csum and uninit_bg are "
4418 			     "redundant flags; please run fsck.");
4419 
4420 	/* Check for a known checksum algorithm */
4421 	if (!ext4_verify_csum_type(sb, es)) {
4422 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4423 			 "unknown checksum algorithm.");
4424 		silent = 1;
4425 		goto cantfind_ext4;
4426 	}
4427 	ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4428 				ext4_orphan_file_block_trigger);
4429 
4430 	/* Load the checksum driver */
4431 	sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4432 	if (IS_ERR(sbi->s_chksum_driver)) {
4433 		ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4434 		ret = PTR_ERR(sbi->s_chksum_driver);
4435 		sbi->s_chksum_driver = NULL;
4436 		goto failed_mount;
4437 	}
4438 
4439 	/* Check superblock checksum */
4440 	if (!ext4_superblock_csum_verify(sb, es)) {
4441 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4442 			 "invalid superblock checksum.  Run e2fsck?");
4443 		silent = 1;
4444 		ret = -EFSBADCRC;
4445 		goto cantfind_ext4;
4446 	}
4447 
4448 	/* Precompute checksum seed for all metadata */
4449 	if (ext4_has_feature_csum_seed(sb))
4450 		sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4451 	else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4452 		sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4453 					       sizeof(es->s_uuid));
4454 
4455 	/* Set defaults before we parse the mount options */
4456 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4457 	set_opt(sb, INIT_INODE_TABLE);
4458 	if (def_mount_opts & EXT4_DEFM_DEBUG)
4459 		set_opt(sb, DEBUG);
4460 	if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4461 		set_opt(sb, GRPID);
4462 	if (def_mount_opts & EXT4_DEFM_UID16)
4463 		set_opt(sb, NO_UID32);
4464 	/* xattr user namespace & acls are now defaulted on */
4465 	set_opt(sb, XATTR_USER);
4466 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4467 	set_opt(sb, POSIX_ACL);
4468 #endif
4469 	if (ext4_has_feature_fast_commit(sb))
4470 		set_opt2(sb, JOURNAL_FAST_COMMIT);
4471 	/* don't forget to enable journal_csum when metadata_csum is enabled. */
4472 	if (ext4_has_metadata_csum(sb))
4473 		set_opt(sb, JOURNAL_CHECKSUM);
4474 
4475 	if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4476 		set_opt(sb, JOURNAL_DATA);
4477 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4478 		set_opt(sb, ORDERED_DATA);
4479 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4480 		set_opt(sb, WRITEBACK_DATA);
4481 
4482 	if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4483 		set_opt(sb, ERRORS_PANIC);
4484 	else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4485 		set_opt(sb, ERRORS_CONT);
4486 	else
4487 		set_opt(sb, ERRORS_RO);
4488 	/* block_validity enabled by default; disable with noblock_validity */
4489 	set_opt(sb, BLOCK_VALIDITY);
4490 	if (def_mount_opts & EXT4_DEFM_DISCARD)
4491 		set_opt(sb, DISCARD);
4492 
4493 	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4494 	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4495 	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4496 	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4497 	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4498 
4499 	if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4500 		set_opt(sb, BARRIER);
4501 
4502 	/*
4503 	 * enable delayed allocation by default
4504 	 * Use -o nodelalloc to turn it off
4505 	 */
4506 	if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4507 	    ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4508 		set_opt(sb, DELALLOC);
4509 
4510 	/*
4511 	 * set default s_li_wait_mult for lazyinit, for the case there is
4512 	 * no mount option specified.
4513 	 */
4514 	sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4515 
4516 	if (le32_to_cpu(es->s_log_block_size) >
4517 	    (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4518 		ext4_msg(sb, KERN_ERR,
4519 			 "Invalid log block size: %u",
4520 			 le32_to_cpu(es->s_log_block_size));
4521 		goto failed_mount;
4522 	}
4523 	if (le32_to_cpu(es->s_log_cluster_size) >
4524 	    (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4525 		ext4_msg(sb, KERN_ERR,
4526 			 "Invalid log cluster size: %u",
4527 			 le32_to_cpu(es->s_log_cluster_size));
4528 		goto failed_mount;
4529 	}
4530 
4531 	blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4532 
4533 	if (blocksize == PAGE_SIZE)
4534 		set_opt(sb, DIOREAD_NOLOCK);
4535 
4536 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4537 		sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4538 		sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4539 	} else {
4540 		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4541 		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4542 		if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4543 			ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4544 				 sbi->s_first_ino);
4545 			goto failed_mount;
4546 		}
4547 		if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4548 		    (!is_power_of_2(sbi->s_inode_size)) ||
4549 		    (sbi->s_inode_size > blocksize)) {
4550 			ext4_msg(sb, KERN_ERR,
4551 			       "unsupported inode size: %d",
4552 			       sbi->s_inode_size);
4553 			ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4554 			goto failed_mount;
4555 		}
4556 		/*
4557 		 * i_atime_extra is the last extra field available for
4558 		 * [acm]times in struct ext4_inode. Checking for that
4559 		 * field should suffice to ensure we have extra space
4560 		 * for all three.
4561 		 */
4562 		if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4563 			sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4564 			sb->s_time_gran = 1;
4565 			sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4566 		} else {
4567 			sb->s_time_gran = NSEC_PER_SEC;
4568 			sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4569 		}
4570 		sb->s_time_min = EXT4_TIMESTAMP_MIN;
4571 	}
4572 	if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4573 		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4574 			EXT4_GOOD_OLD_INODE_SIZE;
4575 		if (ext4_has_feature_extra_isize(sb)) {
4576 			unsigned v, max = (sbi->s_inode_size -
4577 					   EXT4_GOOD_OLD_INODE_SIZE);
4578 
4579 			v = le16_to_cpu(es->s_want_extra_isize);
4580 			if (v > max) {
4581 				ext4_msg(sb, KERN_ERR,
4582 					 "bad s_want_extra_isize: %d", v);
4583 				goto failed_mount;
4584 			}
4585 			if (sbi->s_want_extra_isize < v)
4586 				sbi->s_want_extra_isize = v;
4587 
4588 			v = le16_to_cpu(es->s_min_extra_isize);
4589 			if (v > max) {
4590 				ext4_msg(sb, KERN_ERR,
4591 					 "bad s_min_extra_isize: %d", v);
4592 				goto failed_mount;
4593 			}
4594 			if (sbi->s_want_extra_isize < v)
4595 				sbi->s_want_extra_isize = v;
4596 		}
4597 	}
4598 
4599 	err = parse_apply_sb_mount_options(sb, ctx);
4600 	if (err < 0)
4601 		goto failed_mount;
4602 
4603 	sbi->s_def_mount_opt = sbi->s_mount_opt;
4604 
4605 	err = ext4_check_opt_consistency(fc, sb);
4606 	if (err < 0)
4607 		goto failed_mount;
4608 
4609 	err = ext4_apply_options(fc, sb);
4610 	if (err < 0)
4611 		goto failed_mount;
4612 
4613 #ifdef CONFIG_UNICODE
4614 	if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4615 		const struct ext4_sb_encodings *encoding_info;
4616 		struct unicode_map *encoding;
4617 		__u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4618 
4619 		encoding_info = ext4_sb_read_encoding(es);
4620 		if (!encoding_info) {
4621 			ext4_msg(sb, KERN_ERR,
4622 				 "Encoding requested by superblock is unknown");
4623 			goto failed_mount;
4624 		}
4625 
4626 		encoding = utf8_load(encoding_info->version);
4627 		if (IS_ERR(encoding)) {
4628 			ext4_msg(sb, KERN_ERR,
4629 				 "can't mount with superblock charset: %s-%u.%u.%u "
4630 				 "not supported by the kernel. flags: 0x%x.",
4631 				 encoding_info->name,
4632 				 unicode_major(encoding_info->version),
4633 				 unicode_minor(encoding_info->version),
4634 				 unicode_rev(encoding_info->version),
4635 				 encoding_flags);
4636 			goto failed_mount;
4637 		}
4638 		ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4639 			 "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4640 			 unicode_major(encoding_info->version),
4641 			 unicode_minor(encoding_info->version),
4642 			 unicode_rev(encoding_info->version),
4643 			 encoding_flags);
4644 
4645 		sb->s_encoding = encoding;
4646 		sb->s_encoding_flags = encoding_flags;
4647 	}
4648 #endif
4649 
4650 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4651 		printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4652 		/* can't mount with both data=journal and dioread_nolock. */
4653 		clear_opt(sb, DIOREAD_NOLOCK);
4654 		clear_opt2(sb, JOURNAL_FAST_COMMIT);
4655 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4656 			ext4_msg(sb, KERN_ERR, "can't mount with "
4657 				 "both data=journal and delalloc");
4658 			goto failed_mount;
4659 		}
4660 		if (test_opt(sb, DAX_ALWAYS)) {
4661 			ext4_msg(sb, KERN_ERR, "can't mount with "
4662 				 "both data=journal and dax");
4663 			goto failed_mount;
4664 		}
4665 		if (ext4_has_feature_encrypt(sb)) {
4666 			ext4_msg(sb, KERN_WARNING,
4667 				 "encrypted files will use data=ordered "
4668 				 "instead of data journaling mode");
4669 		}
4670 		if (test_opt(sb, DELALLOC))
4671 			clear_opt(sb, DELALLOC);
4672 	} else {
4673 		sb->s_iflags |= SB_I_CGROUPWB;
4674 	}
4675 
4676 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4677 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4678 
4679 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4680 	    (ext4_has_compat_features(sb) ||
4681 	     ext4_has_ro_compat_features(sb) ||
4682 	     ext4_has_incompat_features(sb)))
4683 		ext4_msg(sb, KERN_WARNING,
4684 		       "feature flags set on rev 0 fs, "
4685 		       "running e2fsck is recommended");
4686 
4687 	if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4688 		set_opt2(sb, HURD_COMPAT);
4689 		if (ext4_has_feature_64bit(sb)) {
4690 			ext4_msg(sb, KERN_ERR,
4691 				 "The Hurd can't support 64-bit file systems");
4692 			goto failed_mount;
4693 		}
4694 
4695 		/*
4696 		 * ea_inode feature uses l_i_version field which is not
4697 		 * available in HURD_COMPAT mode.
4698 		 */
4699 		if (ext4_has_feature_ea_inode(sb)) {
4700 			ext4_msg(sb, KERN_ERR,
4701 				 "ea_inode feature is not supported for Hurd");
4702 			goto failed_mount;
4703 		}
4704 	}
4705 
4706 	if (IS_EXT2_SB(sb)) {
4707 		if (ext2_feature_set_ok(sb))
4708 			ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4709 				 "using the ext4 subsystem");
4710 		else {
4711 			/*
4712 			 * If we're probing be silent, if this looks like
4713 			 * it's actually an ext[34] filesystem.
4714 			 */
4715 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4716 				goto failed_mount;
4717 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4718 				 "to feature incompatibilities");
4719 			goto failed_mount;
4720 		}
4721 	}
4722 
4723 	if (IS_EXT3_SB(sb)) {
4724 		if (ext3_feature_set_ok(sb))
4725 			ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4726 				 "using the ext4 subsystem");
4727 		else {
4728 			/*
4729 			 * If we're probing be silent, if this looks like
4730 			 * it's actually an ext4 filesystem.
4731 			 */
4732 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4733 				goto failed_mount;
4734 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4735 				 "to feature incompatibilities");
4736 			goto failed_mount;
4737 		}
4738 	}
4739 
4740 	/*
4741 	 * Check feature flags regardless of the revision level, since we
4742 	 * previously didn't change the revision level when setting the flags,
4743 	 * so there is a chance incompat flags are set on a rev 0 filesystem.
4744 	 */
4745 	if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4746 		goto failed_mount;
4747 
4748 	if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4749 		ext4_msg(sb, KERN_ERR,
4750 			 "Number of reserved GDT blocks insanely large: %d",
4751 			 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4752 		goto failed_mount;
4753 	}
4754 
4755 	if (sbi->s_daxdev) {
4756 		if (blocksize == PAGE_SIZE)
4757 			set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4758 		else
4759 			ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4760 	}
4761 
4762 	if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4763 		if (ext4_has_feature_inline_data(sb)) {
4764 			ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4765 					" that may contain inline data");
4766 			goto failed_mount;
4767 		}
4768 		if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4769 			ext4_msg(sb, KERN_ERR,
4770 				"DAX unsupported by block device.");
4771 			goto failed_mount;
4772 		}
4773 	}
4774 
4775 	if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4776 		ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4777 			 es->s_encryption_level);
4778 		goto failed_mount;
4779 	}
4780 
4781 	if (sb->s_blocksize != blocksize) {
4782 		/*
4783 		 * bh must be released before kill_bdev(), otherwise
4784 		 * it won't be freed and its page also. kill_bdev()
4785 		 * is called by sb_set_blocksize().
4786 		 */
4787 		brelse(bh);
4788 		/* Validate the filesystem blocksize */
4789 		if (!sb_set_blocksize(sb, blocksize)) {
4790 			ext4_msg(sb, KERN_ERR, "bad block size %d",
4791 					blocksize);
4792 			bh = NULL;
4793 			goto failed_mount;
4794 		}
4795 
4796 		logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4797 		offset = do_div(logical_sb_block, blocksize);
4798 		bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4799 		if (IS_ERR(bh)) {
4800 			ext4_msg(sb, KERN_ERR,
4801 			       "Can't read superblock on 2nd try");
4802 			ret = PTR_ERR(bh);
4803 			bh = NULL;
4804 			goto failed_mount;
4805 		}
4806 		es = (struct ext4_super_block *)(bh->b_data + offset);
4807 		sbi->s_es = es;
4808 		if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4809 			ext4_msg(sb, KERN_ERR,
4810 			       "Magic mismatch, very weird!");
4811 			goto failed_mount;
4812 		}
4813 	}
4814 
4815 	has_huge_files = ext4_has_feature_huge_file(sb);
4816 	sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4817 						      has_huge_files);
4818 	sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4819 
4820 	sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4821 	if (ext4_has_feature_64bit(sb)) {
4822 		if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4823 		    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4824 		    !is_power_of_2(sbi->s_desc_size)) {
4825 			ext4_msg(sb, KERN_ERR,
4826 			       "unsupported descriptor size %lu",
4827 			       sbi->s_desc_size);
4828 			goto failed_mount;
4829 		}
4830 	} else
4831 		sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4832 
4833 	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4834 	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4835 
4836 	sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4837 	if (sbi->s_inodes_per_block == 0)
4838 		goto cantfind_ext4;
4839 	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4840 	    sbi->s_inodes_per_group > blocksize * 8) {
4841 		ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4842 			 sbi->s_inodes_per_group);
4843 		goto failed_mount;
4844 	}
4845 	sbi->s_itb_per_group = sbi->s_inodes_per_group /
4846 					sbi->s_inodes_per_block;
4847 	sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4848 	sbi->s_sbh = bh;
4849 	sbi->s_mount_state = le16_to_cpu(es->s_state);
4850 	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4851 	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4852 
4853 	for (i = 0; i < 4; i++)
4854 		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4855 	sbi->s_def_hash_version = es->s_def_hash_version;
4856 	if (ext4_has_feature_dir_index(sb)) {
4857 		i = le32_to_cpu(es->s_flags);
4858 		if (i & EXT2_FLAGS_UNSIGNED_HASH)
4859 			sbi->s_hash_unsigned = 3;
4860 		else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4861 #ifdef __CHAR_UNSIGNED__
4862 			if (!sb_rdonly(sb))
4863 				es->s_flags |=
4864 					cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4865 			sbi->s_hash_unsigned = 3;
4866 #else
4867 			if (!sb_rdonly(sb))
4868 				es->s_flags |=
4869 					cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4870 #endif
4871 		}
4872 	}
4873 
4874 	/* Handle clustersize */
4875 	clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4876 	if (ext4_has_feature_bigalloc(sb)) {
4877 		if (clustersize < blocksize) {
4878 			ext4_msg(sb, KERN_ERR,
4879 				 "cluster size (%d) smaller than "
4880 				 "block size (%d)", clustersize, blocksize);
4881 			goto failed_mount;
4882 		}
4883 		sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4884 			le32_to_cpu(es->s_log_block_size);
4885 		sbi->s_clusters_per_group =
4886 			le32_to_cpu(es->s_clusters_per_group);
4887 		if (sbi->s_clusters_per_group > blocksize * 8) {
4888 			ext4_msg(sb, KERN_ERR,
4889 				 "#clusters per group too big: %lu",
4890 				 sbi->s_clusters_per_group);
4891 			goto failed_mount;
4892 		}
4893 		if (sbi->s_blocks_per_group !=
4894 		    (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4895 			ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4896 				 "clusters per group (%lu) inconsistent",
4897 				 sbi->s_blocks_per_group,
4898 				 sbi->s_clusters_per_group);
4899 			goto failed_mount;
4900 		}
4901 	} else {
4902 		if (clustersize != blocksize) {
4903 			ext4_msg(sb, KERN_ERR,
4904 				 "fragment/cluster size (%d) != "
4905 				 "block size (%d)", clustersize, blocksize);
4906 			goto failed_mount;
4907 		}
4908 		if (sbi->s_blocks_per_group > blocksize * 8) {
4909 			ext4_msg(sb, KERN_ERR,
4910 				 "#blocks per group too big: %lu",
4911 				 sbi->s_blocks_per_group);
4912 			goto failed_mount;
4913 		}
4914 		sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4915 		sbi->s_cluster_bits = 0;
4916 	}
4917 	sbi->s_cluster_ratio = clustersize / blocksize;
4918 
4919 	/* Do we have standard group size of clustersize * 8 blocks ? */
4920 	if (sbi->s_blocks_per_group == clustersize << 3)
4921 		set_opt2(sb, STD_GROUP_SIZE);
4922 
4923 	/*
4924 	 * Test whether we have more sectors than will fit in sector_t,
4925 	 * and whether the max offset is addressable by the page cache.
4926 	 */
4927 	err = generic_check_addressable(sb->s_blocksize_bits,
4928 					ext4_blocks_count(es));
4929 	if (err) {
4930 		ext4_msg(sb, KERN_ERR, "filesystem"
4931 			 " too large to mount safely on this system");
4932 		goto failed_mount;
4933 	}
4934 
4935 	if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4936 		goto cantfind_ext4;
4937 
4938 	/* check blocks count against device size */
4939 	blocks_count = sb_bdev_nr_blocks(sb);
4940 	if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4941 		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4942 		       "exceeds size of device (%llu blocks)",
4943 		       ext4_blocks_count(es), blocks_count);
4944 		goto failed_mount;
4945 	}
4946 
4947 	/*
4948 	 * It makes no sense for the first data block to be beyond the end
4949 	 * of the filesystem.
4950 	 */
4951 	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4952 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4953 			 "block %u is beyond end of filesystem (%llu)",
4954 			 le32_to_cpu(es->s_first_data_block),
4955 			 ext4_blocks_count(es));
4956 		goto failed_mount;
4957 	}
4958 	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4959 	    (sbi->s_cluster_ratio == 1)) {
4960 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4961 			 "block is 0 with a 1k block and cluster size");
4962 		goto failed_mount;
4963 	}
4964 
4965 	blocks_count = (ext4_blocks_count(es) -
4966 			le32_to_cpu(es->s_first_data_block) +
4967 			EXT4_BLOCKS_PER_GROUP(sb) - 1);
4968 	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4969 	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4970 		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4971 		       "(block count %llu, first data block %u, "
4972 		       "blocks per group %lu)", blocks_count,
4973 		       ext4_blocks_count(es),
4974 		       le32_to_cpu(es->s_first_data_block),
4975 		       EXT4_BLOCKS_PER_GROUP(sb));
4976 		goto failed_mount;
4977 	}
4978 	sbi->s_groups_count = blocks_count;
4979 	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4980 			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4981 	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4982 	    le32_to_cpu(es->s_inodes_count)) {
4983 		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4984 			 le32_to_cpu(es->s_inodes_count),
4985 			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4986 		ret = -EINVAL;
4987 		goto failed_mount;
4988 	}
4989 	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4990 		   EXT4_DESC_PER_BLOCK(sb);
4991 	if (ext4_has_feature_meta_bg(sb)) {
4992 		if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4993 			ext4_msg(sb, KERN_WARNING,
4994 				 "first meta block group too large: %u "
4995 				 "(group descriptor block count %u)",
4996 				 le32_to_cpu(es->s_first_meta_bg), db_count);
4997 			goto failed_mount;
4998 		}
4999 	}
5000 	rcu_assign_pointer(sbi->s_group_desc,
5001 			   kvmalloc_array(db_count,
5002 					  sizeof(struct buffer_head *),
5003 					  GFP_KERNEL));
5004 	if (sbi->s_group_desc == NULL) {
5005 		ext4_msg(sb, KERN_ERR, "not enough memory");
5006 		ret = -ENOMEM;
5007 		goto failed_mount;
5008 	}
5009 
5010 	bgl_lock_init(sbi->s_blockgroup_lock);
5011 
5012 	/* Pre-read the descriptors into the buffer cache */
5013 	for (i = 0; i < db_count; i++) {
5014 		block = descriptor_loc(sb, logical_sb_block, i);
5015 		ext4_sb_breadahead_unmovable(sb, block);
5016 	}
5017 
5018 	for (i = 0; i < db_count; i++) {
5019 		struct buffer_head *bh;
5020 
5021 		block = descriptor_loc(sb, logical_sb_block, i);
5022 		bh = ext4_sb_bread_unmovable(sb, block);
5023 		if (IS_ERR(bh)) {
5024 			ext4_msg(sb, KERN_ERR,
5025 			       "can't read group descriptor %d", i);
5026 			db_count = i;
5027 			ret = PTR_ERR(bh);
5028 			goto failed_mount2;
5029 		}
5030 		rcu_read_lock();
5031 		rcu_dereference(sbi->s_group_desc)[i] = bh;
5032 		rcu_read_unlock();
5033 	}
5034 	sbi->s_gdb_count = db_count;
5035 	if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
5036 		ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
5037 		ret = -EFSCORRUPTED;
5038 		goto failed_mount2;
5039 	}
5040 
5041 	timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5042 	spin_lock_init(&sbi->s_error_lock);
5043 	INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
5044 
5045 	/* Register extent status tree shrinker */
5046 	if (ext4_es_register_shrinker(sbi))
5047 		goto failed_mount3;
5048 
5049 	sbi->s_stripe = ext4_get_stripe_size(sbi);
5050 	sbi->s_extent_max_zeroout_kb = 32;
5051 
5052 	/*
5053 	 * set up enough so that it can read an inode
5054 	 */
5055 	sb->s_op = &ext4_sops;
5056 	sb->s_export_op = &ext4_export_ops;
5057 	sb->s_xattr = ext4_xattr_handlers;
5058 #ifdef CONFIG_FS_ENCRYPTION
5059 	sb->s_cop = &ext4_cryptops;
5060 #endif
5061 #ifdef CONFIG_FS_VERITY
5062 	sb->s_vop = &ext4_verityops;
5063 #endif
5064 #ifdef CONFIG_QUOTA
5065 	sb->dq_op = &ext4_quota_operations;
5066 	if (ext4_has_feature_quota(sb))
5067 		sb->s_qcop = &dquot_quotactl_sysfile_ops;
5068 	else
5069 		sb->s_qcop = &ext4_qctl_operations;
5070 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5071 #endif
5072 	memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5073 
5074 	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5075 	mutex_init(&sbi->s_orphan_lock);
5076 
5077 	/* Initialize fast commit stuff */
5078 	atomic_set(&sbi->s_fc_subtid, 0);
5079 	INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
5080 	INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
5081 	INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
5082 	INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
5083 	sbi->s_fc_bytes = 0;
5084 	ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
5085 	ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
5086 	spin_lock_init(&sbi->s_fc_lock);
5087 	memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
5088 	sbi->s_fc_replay_state.fc_regions = NULL;
5089 	sbi->s_fc_replay_state.fc_regions_size = 0;
5090 	sbi->s_fc_replay_state.fc_regions_used = 0;
5091 	sbi->s_fc_replay_state.fc_regions_valid = 0;
5092 	sbi->s_fc_replay_state.fc_modified_inodes = NULL;
5093 	sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
5094 	sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
5095 
5096 	sb->s_root = NULL;
5097 
5098 	needs_recovery = (es->s_last_orphan != 0 ||
5099 			  ext4_has_feature_orphan_present(sb) ||
5100 			  ext4_has_feature_journal_needs_recovery(sb));
5101 
5102 	if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
5103 		if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
5104 			goto failed_mount3a;
5105 
5106 	/*
5107 	 * The first inode we look at is the journal inode.  Don't try
5108 	 * root first: it may be modified in the journal!
5109 	 */
5110 	if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5111 		err = ext4_load_journal(sb, es, ctx->journal_devnum);
5112 		if (err)
5113 			goto failed_mount3a;
5114 	} else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5115 		   ext4_has_feature_journal_needs_recovery(sb)) {
5116 		ext4_msg(sb, KERN_ERR, "required journal recovery "
5117 		       "suppressed and not mounted read-only");
5118 		goto failed_mount_wq;
5119 	} else {
5120 		/* Nojournal mode, all journal mount options are illegal */
5121 		if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5122 			ext4_msg(sb, KERN_ERR, "can't mount with "
5123 				 "journal_checksum, fs mounted w/o journal");
5124 			goto failed_mount_wq;
5125 		}
5126 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5127 			ext4_msg(sb, KERN_ERR, "can't mount with "
5128 				 "journal_async_commit, fs mounted w/o journal");
5129 			goto failed_mount_wq;
5130 		}
5131 		if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5132 			ext4_msg(sb, KERN_ERR, "can't mount with "
5133 				 "commit=%lu, fs mounted w/o journal",
5134 				 sbi->s_commit_interval / HZ);
5135 			goto failed_mount_wq;
5136 		}
5137 		if (EXT4_MOUNT_DATA_FLAGS &
5138 		    (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5139 			ext4_msg(sb, KERN_ERR, "can't mount with "
5140 				 "data=, fs mounted w/o journal");
5141 			goto failed_mount_wq;
5142 		}
5143 		sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5144 		clear_opt(sb, JOURNAL_CHECKSUM);
5145 		clear_opt(sb, DATA_FLAGS);
5146 		clear_opt2(sb, JOURNAL_FAST_COMMIT);
5147 		sbi->s_journal = NULL;
5148 		needs_recovery = 0;
5149 		goto no_journal;
5150 	}
5151 
5152 	if (ext4_has_feature_64bit(sb) &&
5153 	    !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
5154 				       JBD2_FEATURE_INCOMPAT_64BIT)) {
5155 		ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
5156 		goto failed_mount_wq;
5157 	}
5158 
5159 	if (!set_journal_csum_feature_set(sb)) {
5160 		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
5161 			 "feature set");
5162 		goto failed_mount_wq;
5163 	}
5164 
5165 	if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
5166 		!jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
5167 					  JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
5168 		ext4_msg(sb, KERN_ERR,
5169 			"Failed to set fast commit journal feature");
5170 		goto failed_mount_wq;
5171 	}
5172 
5173 	/* We have now updated the journal if required, so we can
5174 	 * validate the data journaling mode. */
5175 	switch (test_opt(sb, DATA_FLAGS)) {
5176 	case 0:
5177 		/* No mode set, assume a default based on the journal
5178 		 * capabilities: ORDERED_DATA if the journal can
5179 		 * cope, else JOURNAL_DATA
5180 		 */
5181 		if (jbd2_journal_check_available_features
5182 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
5183 			set_opt(sb, ORDERED_DATA);
5184 			sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
5185 		} else {
5186 			set_opt(sb, JOURNAL_DATA);
5187 			sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
5188 		}
5189 		break;
5190 
5191 	case EXT4_MOUNT_ORDERED_DATA:
5192 	case EXT4_MOUNT_WRITEBACK_DATA:
5193 		if (!jbd2_journal_check_available_features
5194 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
5195 			ext4_msg(sb, KERN_ERR, "Journal does not support "
5196 			       "requested data journaling mode");
5197 			goto failed_mount_wq;
5198 		}
5199 		break;
5200 	default:
5201 		break;
5202 	}
5203 
5204 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
5205 	    test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5206 		ext4_msg(sb, KERN_ERR, "can't mount with "
5207 			"journal_async_commit in data=ordered mode");
5208 		goto failed_mount_wq;
5209 	}
5210 
5211 	set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
5212 
5213 	sbi->s_journal->j_submit_inode_data_buffers =
5214 		ext4_journal_submit_inode_data_buffers;
5215 	sbi->s_journal->j_finish_inode_data_buffers =
5216 		ext4_journal_finish_inode_data_buffers;
5217 
5218 no_journal:
5219 	if (!test_opt(sb, NO_MBCACHE)) {
5220 		sbi->s_ea_block_cache = ext4_xattr_create_cache();
5221 		if (!sbi->s_ea_block_cache) {
5222 			ext4_msg(sb, KERN_ERR,
5223 				 "Failed to create ea_block_cache");
5224 			goto failed_mount_wq;
5225 		}
5226 
5227 		if (ext4_has_feature_ea_inode(sb)) {
5228 			sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5229 			if (!sbi->s_ea_inode_cache) {
5230 				ext4_msg(sb, KERN_ERR,
5231 					 "Failed to create ea_inode_cache");
5232 				goto failed_mount_wq;
5233 			}
5234 		}
5235 	}
5236 
5237 	if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
5238 		ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
5239 		goto failed_mount_wq;
5240 	}
5241 
5242 	if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
5243 	    !ext4_has_feature_encrypt(sb)) {
5244 		ext4_set_feature_encrypt(sb);
5245 		ext4_commit_super(sb);
5246 	}
5247 
5248 	/*
5249 	 * Get the # of file system overhead blocks from the
5250 	 * superblock if present.
5251 	 */
5252 	if (es->s_overhead_clusters)
5253 		sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5254 	else {
5255 		err = ext4_calculate_overhead(sb);
5256 		if (err)
5257 			goto failed_mount_wq;
5258 	}
5259 
5260 	/*
5261 	 * The maximum number of concurrent works can be high and
5262 	 * concurrency isn't really necessary.  Limit it to 1.
5263 	 */
5264 	EXT4_SB(sb)->rsv_conversion_wq =
5265 		alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5266 	if (!EXT4_SB(sb)->rsv_conversion_wq) {
5267 		printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5268 		ret = -ENOMEM;
5269 		goto failed_mount4;
5270 	}
5271 
5272 	/*
5273 	 * The jbd2_journal_load will have done any necessary log recovery,
5274 	 * so we can safely mount the rest of the filesystem now.
5275 	 */
5276 
5277 	root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5278 	if (IS_ERR(root)) {
5279 		ext4_msg(sb, KERN_ERR, "get root inode failed");
5280 		ret = PTR_ERR(root);
5281 		root = NULL;
5282 		goto failed_mount4;
5283 	}
5284 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5285 		ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5286 		iput(root);
5287 		goto failed_mount4;
5288 	}
5289 
5290 	sb->s_root = d_make_root(root);
5291 	if (!sb->s_root) {
5292 		ext4_msg(sb, KERN_ERR, "get root dentry failed");
5293 		ret = -ENOMEM;
5294 		goto failed_mount4;
5295 	}
5296 
5297 	ret = ext4_setup_super(sb, es, sb_rdonly(sb));
5298 	if (ret == -EROFS) {
5299 		sb->s_flags |= SB_RDONLY;
5300 		ret = 0;
5301 	} else if (ret)
5302 		goto failed_mount4a;
5303 
5304 	ext4_set_resv_clusters(sb);
5305 
5306 	if (test_opt(sb, BLOCK_VALIDITY)) {
5307 		err = ext4_setup_system_zone(sb);
5308 		if (err) {
5309 			ext4_msg(sb, KERN_ERR, "failed to initialize system "
5310 				 "zone (%d)", err);
5311 			goto failed_mount4a;
5312 		}
5313 	}
5314 	ext4_fc_replay_cleanup(sb);
5315 
5316 	ext4_ext_init(sb);
5317 
5318 	/*
5319 	 * Enable optimize_scan if number of groups is > threshold. This can be
5320 	 * turned off by passing "mb_optimize_scan=0". This can also be
5321 	 * turned on forcefully by passing "mb_optimize_scan=1".
5322 	 */
5323 	if (ctx->mb_optimize_scan == 1)
5324 		set_opt2(sb, MB_OPTIMIZE_SCAN);
5325 	else if (ctx->mb_optimize_scan == 0)
5326 		clear_opt2(sb, MB_OPTIMIZE_SCAN);
5327 	else if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5328 		set_opt2(sb, MB_OPTIMIZE_SCAN);
5329 
5330 	err = ext4_mb_init(sb);
5331 	if (err) {
5332 		ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5333 			 err);
5334 		goto failed_mount5;
5335 	}
5336 
5337 	/*
5338 	 * We can only set up the journal commit callback once
5339 	 * mballoc is initialized
5340 	 */
5341 	if (sbi->s_journal)
5342 		sbi->s_journal->j_commit_callback =
5343 			ext4_journal_commit_callback;
5344 
5345 	block = ext4_count_free_clusters(sb);
5346 	ext4_free_blocks_count_set(sbi->s_es,
5347 				   EXT4_C2B(sbi, block));
5348 	err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5349 				  GFP_KERNEL);
5350 	if (!err) {
5351 		unsigned long freei = ext4_count_free_inodes(sb);
5352 		sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5353 		err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5354 					  GFP_KERNEL);
5355 	}
5356 	/*
5357 	 * Update the checksum after updating free space/inode
5358 	 * counters.  Otherwise the superblock can have an incorrect
5359 	 * checksum in the buffer cache until it is written out and
5360 	 * e2fsprogs programs trying to open a file system immediately
5361 	 * after it is mounted can fail.
5362 	 */
5363 	ext4_superblock_csum_set(sb);
5364 	if (!err)
5365 		err = percpu_counter_init(&sbi->s_dirs_counter,
5366 					  ext4_count_dirs(sb), GFP_KERNEL);
5367 	if (!err)
5368 		err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5369 					  GFP_KERNEL);
5370 	if (!err)
5371 		err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
5372 					  GFP_KERNEL);
5373 	if (!err)
5374 		err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5375 
5376 	if (err) {
5377 		ext4_msg(sb, KERN_ERR, "insufficient memory");
5378 		goto failed_mount6;
5379 	}
5380 
5381 	if (ext4_has_feature_flex_bg(sb))
5382 		if (!ext4_fill_flex_info(sb)) {
5383 			ext4_msg(sb, KERN_ERR,
5384 			       "unable to initialize "
5385 			       "flex_bg meta info!");
5386 			ret = -ENOMEM;
5387 			goto failed_mount6;
5388 		}
5389 
5390 	err = ext4_register_li_request(sb, first_not_zeroed);
5391 	if (err)
5392 		goto failed_mount6;
5393 
5394 	err = ext4_register_sysfs(sb);
5395 	if (err)
5396 		goto failed_mount7;
5397 
5398 	err = ext4_init_orphan_info(sb);
5399 	if (err)
5400 		goto failed_mount8;
5401 #ifdef CONFIG_QUOTA
5402 	/* Enable quota usage during mount. */
5403 	if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5404 		err = ext4_enable_quotas(sb);
5405 		if (err)
5406 			goto failed_mount9;
5407 	}
5408 #endif  /* CONFIG_QUOTA */
5409 
5410 	/*
5411 	 * Save the original bdev mapping's wb_err value which could be
5412 	 * used to detect the metadata async write error.
5413 	 */
5414 	spin_lock_init(&sbi->s_bdev_wb_lock);
5415 	errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5416 				 &sbi->s_bdev_wb_err);
5417 	sb->s_bdev->bd_super = sb;
5418 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5419 	ext4_orphan_cleanup(sb, es);
5420 	EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5421 	if (needs_recovery) {
5422 		ext4_msg(sb, KERN_INFO, "recovery complete");
5423 		err = ext4_mark_recovery_complete(sb, es);
5424 		if (err)
5425 			goto failed_mount9;
5426 	}
5427 
5428 	if (test_opt(sb, DISCARD)) {
5429 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
5430 		if (!blk_queue_discard(q))
5431 			ext4_msg(sb, KERN_WARNING,
5432 				 "mounting with \"discard\" option, but "
5433 				 "the device does not support discard");
5434 	}
5435 
5436 	if (es->s_error_count)
5437 		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5438 
5439 	/* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5440 	ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5441 	ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5442 	ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5443 	atomic_set(&sbi->s_warning_count, 0);
5444 	atomic_set(&sbi->s_msg_count, 0);
5445 
5446 	return 0;
5447 
5448 cantfind_ext4:
5449 	if (!silent)
5450 		ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5451 	goto failed_mount;
5452 
5453 failed_mount9:
5454 	ext4_release_orphan_info(sb);
5455 failed_mount8:
5456 	ext4_unregister_sysfs(sb);
5457 	kobject_put(&sbi->s_kobj);
5458 failed_mount7:
5459 	ext4_unregister_li_request(sb);
5460 failed_mount6:
5461 	ext4_mb_release(sb);
5462 	rcu_read_lock();
5463 	flex_groups = rcu_dereference(sbi->s_flex_groups);
5464 	if (flex_groups) {
5465 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5466 			kvfree(flex_groups[i]);
5467 		kvfree(flex_groups);
5468 	}
5469 	rcu_read_unlock();
5470 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
5471 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
5472 	percpu_counter_destroy(&sbi->s_dirs_counter);
5473 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5474 	percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
5475 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
5476 failed_mount5:
5477 	ext4_ext_release(sb);
5478 	ext4_release_system_zone(sb);
5479 failed_mount4a:
5480 	dput(sb->s_root);
5481 	sb->s_root = NULL;
5482 failed_mount4:
5483 	ext4_msg(sb, KERN_ERR, "mount failed");
5484 	if (EXT4_SB(sb)->rsv_conversion_wq)
5485 		destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5486 failed_mount_wq:
5487 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5488 	sbi->s_ea_inode_cache = NULL;
5489 
5490 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5491 	sbi->s_ea_block_cache = NULL;
5492 
5493 	if (sbi->s_journal) {
5494 		/* flush s_error_work before journal destroy. */
5495 		flush_work(&sbi->s_error_work);
5496 		jbd2_journal_destroy(sbi->s_journal);
5497 		sbi->s_journal = NULL;
5498 	}
5499 failed_mount3a:
5500 	ext4_es_unregister_shrinker(sbi);
5501 failed_mount3:
5502 	/* flush s_error_work before sbi destroy */
5503 	flush_work(&sbi->s_error_work);
5504 	del_timer_sync(&sbi->s_err_report);
5505 	ext4_stop_mmpd(sbi);
5506 failed_mount2:
5507 	rcu_read_lock();
5508 	group_desc = rcu_dereference(sbi->s_group_desc);
5509 	for (i = 0; i < db_count; i++)
5510 		brelse(group_desc[i]);
5511 	kvfree(group_desc);
5512 	rcu_read_unlock();
5513 failed_mount:
5514 	if (sbi->s_chksum_driver)
5515 		crypto_free_shash(sbi->s_chksum_driver);
5516 
5517 #ifdef CONFIG_UNICODE
5518 	utf8_unload(sb->s_encoding);
5519 #endif
5520 
5521 #ifdef CONFIG_QUOTA
5522 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5523 		kfree(get_qf_name(sb, sbi, i));
5524 #endif
5525 	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5526 	/* ext4_blkdev_remove() calls kill_bdev(), release bh before it. */
5527 	brelse(bh);
5528 	ext4_blkdev_remove(sbi);
5529 out_fail:
5530 	sb->s_fs_info = NULL;
5531 	return err ? err : ret;
5532 }
5533 
5534 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5535 {
5536 	struct ext4_fs_context *ctx = fc->fs_private;
5537 	struct ext4_sb_info *sbi;
5538 	const char *descr;
5539 	int ret;
5540 
5541 	sbi = ext4_alloc_sbi(sb);
5542 	if (!sbi)
5543 		ret = -ENOMEM;
5544 
5545 	fc->s_fs_info = sbi;
5546 
5547 	/* Cleanup superblock name */
5548 	strreplace(sb->s_id, '/', '!');
5549 
5550 	sbi->s_sb_block = 1;	/* Default super block location */
5551 	if (ctx->spec & EXT4_SPEC_s_sb_block)
5552 		sbi->s_sb_block = ctx->s_sb_block;
5553 
5554 	ret = __ext4_fill_super(fc, sb);
5555 	if (ret < 0)
5556 		goto free_sbi;
5557 
5558 	if (sbi->s_journal) {
5559 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5560 			descr = " journalled data mode";
5561 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5562 			descr = " ordered data mode";
5563 		else
5564 			descr = " writeback data mode";
5565 	} else
5566 		descr = "out journal";
5567 
5568 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5569 		ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5570 			 "Quota mode: %s.", descr, ext4_quota_mode(sb));
5571 
5572 	return 0;
5573 
5574 free_sbi:
5575 	ext4_free_sbi(sbi);
5576 	fc->s_fs_info = NULL;
5577 	return ret;
5578 }
5579 
5580 static int ext4_get_tree(struct fs_context *fc)
5581 {
5582 	return get_tree_bdev(fc, ext4_fill_super);
5583 }
5584 
5585 /*
5586  * Setup any per-fs journal parameters now.  We'll do this both on
5587  * initial mount, once the journal has been initialised but before we've
5588  * done any recovery; and again on any subsequent remount.
5589  */
5590 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5591 {
5592 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5593 
5594 	journal->j_commit_interval = sbi->s_commit_interval;
5595 	journal->j_min_batch_time = sbi->s_min_batch_time;
5596 	journal->j_max_batch_time = sbi->s_max_batch_time;
5597 	ext4_fc_init(sb, journal);
5598 
5599 	write_lock(&journal->j_state_lock);
5600 	if (test_opt(sb, BARRIER))
5601 		journal->j_flags |= JBD2_BARRIER;
5602 	else
5603 		journal->j_flags &= ~JBD2_BARRIER;
5604 	if (test_opt(sb, DATA_ERR_ABORT))
5605 		journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5606 	else
5607 		journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5608 	write_unlock(&journal->j_state_lock);
5609 }
5610 
5611 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5612 					     unsigned int journal_inum)
5613 {
5614 	struct inode *journal_inode;
5615 
5616 	/*
5617 	 * Test for the existence of a valid inode on disk.  Bad things
5618 	 * happen if we iget() an unused inode, as the subsequent iput()
5619 	 * will try to delete it.
5620 	 */
5621 	journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5622 	if (IS_ERR(journal_inode)) {
5623 		ext4_msg(sb, KERN_ERR, "no journal found");
5624 		return NULL;
5625 	}
5626 	if (!journal_inode->i_nlink) {
5627 		make_bad_inode(journal_inode);
5628 		iput(journal_inode);
5629 		ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5630 		return NULL;
5631 	}
5632 
5633 	jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5634 		  journal_inode, journal_inode->i_size);
5635 	if (!S_ISREG(journal_inode->i_mode)) {
5636 		ext4_msg(sb, KERN_ERR, "invalid journal inode");
5637 		iput(journal_inode);
5638 		return NULL;
5639 	}
5640 	return journal_inode;
5641 }
5642 
5643 static journal_t *ext4_get_journal(struct super_block *sb,
5644 				   unsigned int journal_inum)
5645 {
5646 	struct inode *journal_inode;
5647 	journal_t *journal;
5648 
5649 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5650 		return NULL;
5651 
5652 	journal_inode = ext4_get_journal_inode(sb, journal_inum);
5653 	if (!journal_inode)
5654 		return NULL;
5655 
5656 	journal = jbd2_journal_init_inode(journal_inode);
5657 	if (!journal) {
5658 		ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5659 		iput(journal_inode);
5660 		return NULL;
5661 	}
5662 	journal->j_private = sb;
5663 	ext4_init_journal_params(sb, journal);
5664 	return journal;
5665 }
5666 
5667 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5668 				       dev_t j_dev)
5669 {
5670 	struct buffer_head *bh;
5671 	journal_t *journal;
5672 	ext4_fsblk_t start;
5673 	ext4_fsblk_t len;
5674 	int hblock, blocksize;
5675 	ext4_fsblk_t sb_block;
5676 	unsigned long offset;
5677 	struct ext4_super_block *es;
5678 	struct block_device *bdev;
5679 
5680 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5681 		return NULL;
5682 
5683 	bdev = ext4_blkdev_get(j_dev, sb);
5684 	if (bdev == NULL)
5685 		return NULL;
5686 
5687 	blocksize = sb->s_blocksize;
5688 	hblock = bdev_logical_block_size(bdev);
5689 	if (blocksize < hblock) {
5690 		ext4_msg(sb, KERN_ERR,
5691 			"blocksize too small for journal device");
5692 		goto out_bdev;
5693 	}
5694 
5695 	sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5696 	offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5697 	set_blocksize(bdev, blocksize);
5698 	if (!(bh = __bread(bdev, sb_block, blocksize))) {
5699 		ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5700 		       "external journal");
5701 		goto out_bdev;
5702 	}
5703 
5704 	es = (struct ext4_super_block *) (bh->b_data + offset);
5705 	if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5706 	    !(le32_to_cpu(es->s_feature_incompat) &
5707 	      EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5708 		ext4_msg(sb, KERN_ERR, "external journal has "
5709 					"bad superblock");
5710 		brelse(bh);
5711 		goto out_bdev;
5712 	}
5713 
5714 	if ((le32_to_cpu(es->s_feature_ro_compat) &
5715 	     EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5716 	    es->s_checksum != ext4_superblock_csum(sb, es)) {
5717 		ext4_msg(sb, KERN_ERR, "external journal has "
5718 				       "corrupt superblock");
5719 		brelse(bh);
5720 		goto out_bdev;
5721 	}
5722 
5723 	if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5724 		ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5725 		brelse(bh);
5726 		goto out_bdev;
5727 	}
5728 
5729 	len = ext4_blocks_count(es);
5730 	start = sb_block + 1;
5731 	brelse(bh);	/* we're done with the superblock */
5732 
5733 	journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5734 					start, len, blocksize);
5735 	if (!journal) {
5736 		ext4_msg(sb, KERN_ERR, "failed to create device journal");
5737 		goto out_bdev;
5738 	}
5739 	journal->j_private = sb;
5740 	if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5741 		ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5742 		goto out_journal;
5743 	}
5744 	if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5745 		ext4_msg(sb, KERN_ERR, "External journal has more than one "
5746 					"user (unsupported) - %d",
5747 			be32_to_cpu(journal->j_superblock->s_nr_users));
5748 		goto out_journal;
5749 	}
5750 	EXT4_SB(sb)->s_journal_bdev = bdev;
5751 	ext4_init_journal_params(sb, journal);
5752 	return journal;
5753 
5754 out_journal:
5755 	jbd2_journal_destroy(journal);
5756 out_bdev:
5757 	ext4_blkdev_put(bdev);
5758 	return NULL;
5759 }
5760 
5761 static int ext4_load_journal(struct super_block *sb,
5762 			     struct ext4_super_block *es,
5763 			     unsigned long journal_devnum)
5764 {
5765 	journal_t *journal;
5766 	unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5767 	dev_t journal_dev;
5768 	int err = 0;
5769 	int really_read_only;
5770 	int journal_dev_ro;
5771 
5772 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5773 		return -EFSCORRUPTED;
5774 
5775 	if (journal_devnum &&
5776 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5777 		ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5778 			"numbers have changed");
5779 		journal_dev = new_decode_dev(journal_devnum);
5780 	} else
5781 		journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5782 
5783 	if (journal_inum && journal_dev) {
5784 		ext4_msg(sb, KERN_ERR,
5785 			 "filesystem has both journal inode and journal device!");
5786 		return -EINVAL;
5787 	}
5788 
5789 	if (journal_inum) {
5790 		journal = ext4_get_journal(sb, journal_inum);
5791 		if (!journal)
5792 			return -EINVAL;
5793 	} else {
5794 		journal = ext4_get_dev_journal(sb, journal_dev);
5795 		if (!journal)
5796 			return -EINVAL;
5797 	}
5798 
5799 	journal_dev_ro = bdev_read_only(journal->j_dev);
5800 	really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5801 
5802 	if (journal_dev_ro && !sb_rdonly(sb)) {
5803 		ext4_msg(sb, KERN_ERR,
5804 			 "journal device read-only, try mounting with '-o ro'");
5805 		err = -EROFS;
5806 		goto err_out;
5807 	}
5808 
5809 	/*
5810 	 * Are we loading a blank journal or performing recovery after a
5811 	 * crash?  For recovery, we need to check in advance whether we
5812 	 * can get read-write access to the device.
5813 	 */
5814 	if (ext4_has_feature_journal_needs_recovery(sb)) {
5815 		if (sb_rdonly(sb)) {
5816 			ext4_msg(sb, KERN_INFO, "INFO: recovery "
5817 					"required on readonly filesystem");
5818 			if (really_read_only) {
5819 				ext4_msg(sb, KERN_ERR, "write access "
5820 					"unavailable, cannot proceed "
5821 					"(try mounting with noload)");
5822 				err = -EROFS;
5823 				goto err_out;
5824 			}
5825 			ext4_msg(sb, KERN_INFO, "write access will "
5826 			       "be enabled during recovery");
5827 		}
5828 	}
5829 
5830 	if (!(journal->j_flags & JBD2_BARRIER))
5831 		ext4_msg(sb, KERN_INFO, "barriers disabled");
5832 
5833 	if (!ext4_has_feature_journal_needs_recovery(sb))
5834 		err = jbd2_journal_wipe(journal, !really_read_only);
5835 	if (!err) {
5836 		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5837 		if (save)
5838 			memcpy(save, ((char *) es) +
5839 			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5840 		err = jbd2_journal_load(journal);
5841 		if (save)
5842 			memcpy(((char *) es) + EXT4_S_ERR_START,
5843 			       save, EXT4_S_ERR_LEN);
5844 		kfree(save);
5845 	}
5846 
5847 	if (err) {
5848 		ext4_msg(sb, KERN_ERR, "error loading journal");
5849 		goto err_out;
5850 	}
5851 
5852 	EXT4_SB(sb)->s_journal = journal;
5853 	err = ext4_clear_journal_err(sb, es);
5854 	if (err) {
5855 		EXT4_SB(sb)->s_journal = NULL;
5856 		jbd2_journal_destroy(journal);
5857 		return err;
5858 	}
5859 
5860 	if (!really_read_only && journal_devnum &&
5861 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5862 		es->s_journal_dev = cpu_to_le32(journal_devnum);
5863 
5864 		/* Make sure we flush the recovery flag to disk. */
5865 		ext4_commit_super(sb);
5866 	}
5867 
5868 	return 0;
5869 
5870 err_out:
5871 	jbd2_journal_destroy(journal);
5872 	return err;
5873 }
5874 
5875 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5876 static void ext4_update_super(struct super_block *sb)
5877 {
5878 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5879 	struct ext4_super_block *es = sbi->s_es;
5880 	struct buffer_head *sbh = sbi->s_sbh;
5881 
5882 	lock_buffer(sbh);
5883 	/*
5884 	 * If the file system is mounted read-only, don't update the
5885 	 * superblock write time.  This avoids updating the superblock
5886 	 * write time when we are mounting the root file system
5887 	 * read/only but we need to replay the journal; at that point,
5888 	 * for people who are east of GMT and who make their clock
5889 	 * tick in localtime for Windows bug-for-bug compatibility,
5890 	 * the clock is set in the future, and this will cause e2fsck
5891 	 * to complain and force a full file system check.
5892 	 */
5893 	if (!(sb->s_flags & SB_RDONLY))
5894 		ext4_update_tstamp(es, s_wtime);
5895 	es->s_kbytes_written =
5896 		cpu_to_le64(sbi->s_kbytes_written +
5897 		    ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5898 		      sbi->s_sectors_written_start) >> 1));
5899 	if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5900 		ext4_free_blocks_count_set(es,
5901 			EXT4_C2B(sbi, percpu_counter_sum_positive(
5902 				&sbi->s_freeclusters_counter)));
5903 	if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5904 		es->s_free_inodes_count =
5905 			cpu_to_le32(percpu_counter_sum_positive(
5906 				&sbi->s_freeinodes_counter));
5907 	/* Copy error information to the on-disk superblock */
5908 	spin_lock(&sbi->s_error_lock);
5909 	if (sbi->s_add_error_count > 0) {
5910 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5911 		if (!es->s_first_error_time && !es->s_first_error_time_hi) {
5912 			__ext4_update_tstamp(&es->s_first_error_time,
5913 					     &es->s_first_error_time_hi,
5914 					     sbi->s_first_error_time);
5915 			strncpy(es->s_first_error_func, sbi->s_first_error_func,
5916 				sizeof(es->s_first_error_func));
5917 			es->s_first_error_line =
5918 				cpu_to_le32(sbi->s_first_error_line);
5919 			es->s_first_error_ino =
5920 				cpu_to_le32(sbi->s_first_error_ino);
5921 			es->s_first_error_block =
5922 				cpu_to_le64(sbi->s_first_error_block);
5923 			es->s_first_error_errcode =
5924 				ext4_errno_to_code(sbi->s_first_error_code);
5925 		}
5926 		__ext4_update_tstamp(&es->s_last_error_time,
5927 				     &es->s_last_error_time_hi,
5928 				     sbi->s_last_error_time);
5929 		strncpy(es->s_last_error_func, sbi->s_last_error_func,
5930 			sizeof(es->s_last_error_func));
5931 		es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
5932 		es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
5933 		es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
5934 		es->s_last_error_errcode =
5935 				ext4_errno_to_code(sbi->s_last_error_code);
5936 		/*
5937 		 * Start the daily error reporting function if it hasn't been
5938 		 * started already
5939 		 */
5940 		if (!es->s_error_count)
5941 			mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
5942 		le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
5943 		sbi->s_add_error_count = 0;
5944 	}
5945 	spin_unlock(&sbi->s_error_lock);
5946 
5947 	ext4_superblock_csum_set(sb);
5948 	unlock_buffer(sbh);
5949 }
5950 
5951 static int ext4_commit_super(struct super_block *sb)
5952 {
5953 	struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5954 	int error = 0;
5955 
5956 	if (!sbh)
5957 		return -EINVAL;
5958 	if (block_device_ejected(sb))
5959 		return -ENODEV;
5960 
5961 	ext4_update_super(sb);
5962 
5963 	if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5964 		/*
5965 		 * Oh, dear.  A previous attempt to write the
5966 		 * superblock failed.  This could happen because the
5967 		 * USB device was yanked out.  Or it could happen to
5968 		 * be a transient write error and maybe the block will
5969 		 * be remapped.  Nothing we can do but to retry the
5970 		 * write and hope for the best.
5971 		 */
5972 		ext4_msg(sb, KERN_ERR, "previous I/O error to "
5973 		       "superblock detected");
5974 		clear_buffer_write_io_error(sbh);
5975 		set_buffer_uptodate(sbh);
5976 	}
5977 	BUFFER_TRACE(sbh, "marking dirty");
5978 	mark_buffer_dirty(sbh);
5979 	error = __sync_dirty_buffer(sbh,
5980 		REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5981 	if (buffer_write_io_error(sbh)) {
5982 		ext4_msg(sb, KERN_ERR, "I/O error while writing "
5983 		       "superblock");
5984 		clear_buffer_write_io_error(sbh);
5985 		set_buffer_uptodate(sbh);
5986 	}
5987 	return error;
5988 }
5989 
5990 /*
5991  * Have we just finished recovery?  If so, and if we are mounting (or
5992  * remounting) the filesystem readonly, then we will end up with a
5993  * consistent fs on disk.  Record that fact.
5994  */
5995 static int ext4_mark_recovery_complete(struct super_block *sb,
5996 				       struct ext4_super_block *es)
5997 {
5998 	int err;
5999 	journal_t *journal = EXT4_SB(sb)->s_journal;
6000 
6001 	if (!ext4_has_feature_journal(sb)) {
6002 		if (journal != NULL) {
6003 			ext4_error(sb, "Journal got removed while the fs was "
6004 				   "mounted!");
6005 			return -EFSCORRUPTED;
6006 		}
6007 		return 0;
6008 	}
6009 	jbd2_journal_lock_updates(journal);
6010 	err = jbd2_journal_flush(journal, 0);
6011 	if (err < 0)
6012 		goto out;
6013 
6014 	if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6015 	    ext4_has_feature_orphan_present(sb))) {
6016 		if (!ext4_orphan_file_empty(sb)) {
6017 			ext4_error(sb, "Orphan file not empty on read-only fs.");
6018 			err = -EFSCORRUPTED;
6019 			goto out;
6020 		}
6021 		ext4_clear_feature_journal_needs_recovery(sb);
6022 		ext4_clear_feature_orphan_present(sb);
6023 		ext4_commit_super(sb);
6024 	}
6025 out:
6026 	jbd2_journal_unlock_updates(journal);
6027 	return err;
6028 }
6029 
6030 /*
6031  * If we are mounting (or read-write remounting) a filesystem whose journal
6032  * has recorded an error from a previous lifetime, move that error to the
6033  * main filesystem now.
6034  */
6035 static int ext4_clear_journal_err(struct super_block *sb,
6036 				   struct ext4_super_block *es)
6037 {
6038 	journal_t *journal;
6039 	int j_errno;
6040 	const char *errstr;
6041 
6042 	if (!ext4_has_feature_journal(sb)) {
6043 		ext4_error(sb, "Journal got removed while the fs was mounted!");
6044 		return -EFSCORRUPTED;
6045 	}
6046 
6047 	journal = EXT4_SB(sb)->s_journal;
6048 
6049 	/*
6050 	 * Now check for any error status which may have been recorded in the
6051 	 * journal by a prior ext4_error() or ext4_abort()
6052 	 */
6053 
6054 	j_errno = jbd2_journal_errno(journal);
6055 	if (j_errno) {
6056 		char nbuf[16];
6057 
6058 		errstr = ext4_decode_error(sb, j_errno, nbuf);
6059 		ext4_warning(sb, "Filesystem error recorded "
6060 			     "from previous mount: %s", errstr);
6061 		ext4_warning(sb, "Marking fs in need of filesystem check.");
6062 
6063 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6064 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6065 		ext4_commit_super(sb);
6066 
6067 		jbd2_journal_clear_err(journal);
6068 		jbd2_journal_update_sb_errno(journal);
6069 	}
6070 	return 0;
6071 }
6072 
6073 /*
6074  * Force the running and committing transactions to commit,
6075  * and wait on the commit.
6076  */
6077 int ext4_force_commit(struct super_block *sb)
6078 {
6079 	journal_t *journal;
6080 
6081 	if (sb_rdonly(sb))
6082 		return 0;
6083 
6084 	journal = EXT4_SB(sb)->s_journal;
6085 	return ext4_journal_force_commit(journal);
6086 }
6087 
6088 static int ext4_sync_fs(struct super_block *sb, int wait)
6089 {
6090 	int ret = 0;
6091 	tid_t target;
6092 	bool needs_barrier = false;
6093 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6094 
6095 	if (unlikely(ext4_forced_shutdown(sbi)))
6096 		return 0;
6097 
6098 	trace_ext4_sync_fs(sb, wait);
6099 	flush_workqueue(sbi->rsv_conversion_wq);
6100 	/*
6101 	 * Writeback quota in non-journalled quota case - journalled quota has
6102 	 * no dirty dquots
6103 	 */
6104 	dquot_writeback_dquots(sb, -1);
6105 	/*
6106 	 * Data writeback is possible w/o journal transaction, so barrier must
6107 	 * being sent at the end of the function. But we can skip it if
6108 	 * transaction_commit will do it for us.
6109 	 */
6110 	if (sbi->s_journal) {
6111 		target = jbd2_get_latest_transaction(sbi->s_journal);
6112 		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6113 		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6114 			needs_barrier = true;
6115 
6116 		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6117 			if (wait)
6118 				ret = jbd2_log_wait_commit(sbi->s_journal,
6119 							   target);
6120 		}
6121 	} else if (wait && test_opt(sb, BARRIER))
6122 		needs_barrier = true;
6123 	if (needs_barrier) {
6124 		int err;
6125 		err = blkdev_issue_flush(sb->s_bdev);
6126 		if (!ret)
6127 			ret = err;
6128 	}
6129 
6130 	return ret;
6131 }
6132 
6133 /*
6134  * LVM calls this function before a (read-only) snapshot is created.  This
6135  * gives us a chance to flush the journal completely and mark the fs clean.
6136  *
6137  * Note that only this function cannot bring a filesystem to be in a clean
6138  * state independently. It relies on upper layer to stop all data & metadata
6139  * modifications.
6140  */
6141 static int ext4_freeze(struct super_block *sb)
6142 {
6143 	int error = 0;
6144 	journal_t *journal;
6145 
6146 	if (sb_rdonly(sb))
6147 		return 0;
6148 
6149 	journal = EXT4_SB(sb)->s_journal;
6150 
6151 	if (journal) {
6152 		/* Now we set up the journal barrier. */
6153 		jbd2_journal_lock_updates(journal);
6154 
6155 		/*
6156 		 * Don't clear the needs_recovery flag if we failed to
6157 		 * flush the journal.
6158 		 */
6159 		error = jbd2_journal_flush(journal, 0);
6160 		if (error < 0)
6161 			goto out;
6162 
6163 		/* Journal blocked and flushed, clear needs_recovery flag. */
6164 		ext4_clear_feature_journal_needs_recovery(sb);
6165 		if (ext4_orphan_file_empty(sb))
6166 			ext4_clear_feature_orphan_present(sb);
6167 	}
6168 
6169 	error = ext4_commit_super(sb);
6170 out:
6171 	if (journal)
6172 		/* we rely on upper layer to stop further updates */
6173 		jbd2_journal_unlock_updates(journal);
6174 	return error;
6175 }
6176 
6177 /*
6178  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6179  * flag here, even though the filesystem is not technically dirty yet.
6180  */
6181 static int ext4_unfreeze(struct super_block *sb)
6182 {
6183 	if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
6184 		return 0;
6185 
6186 	if (EXT4_SB(sb)->s_journal) {
6187 		/* Reset the needs_recovery flag before the fs is unlocked. */
6188 		ext4_set_feature_journal_needs_recovery(sb);
6189 		if (ext4_has_feature_orphan_file(sb))
6190 			ext4_set_feature_orphan_present(sb);
6191 	}
6192 
6193 	ext4_commit_super(sb);
6194 	return 0;
6195 }
6196 
6197 /*
6198  * Structure to save mount options for ext4_remount's benefit
6199  */
6200 struct ext4_mount_options {
6201 	unsigned long s_mount_opt;
6202 	unsigned long s_mount_opt2;
6203 	kuid_t s_resuid;
6204 	kgid_t s_resgid;
6205 	unsigned long s_commit_interval;
6206 	u32 s_min_batch_time, s_max_batch_time;
6207 #ifdef CONFIG_QUOTA
6208 	int s_jquota_fmt;
6209 	char *s_qf_names[EXT4_MAXQUOTAS];
6210 #endif
6211 };
6212 
6213 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6214 {
6215 	struct ext4_fs_context *ctx = fc->fs_private;
6216 	struct ext4_super_block *es;
6217 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6218 	unsigned long old_sb_flags;
6219 	struct ext4_mount_options old_opts;
6220 	ext4_group_t g;
6221 	int err = 0;
6222 #ifdef CONFIG_QUOTA
6223 	int enable_quota = 0;
6224 	int i, j;
6225 	char *to_free[EXT4_MAXQUOTAS];
6226 #endif
6227 
6228 	ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6229 
6230 	/* Store the original options */
6231 	old_sb_flags = sb->s_flags;
6232 	old_opts.s_mount_opt = sbi->s_mount_opt;
6233 	old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6234 	old_opts.s_resuid = sbi->s_resuid;
6235 	old_opts.s_resgid = sbi->s_resgid;
6236 	old_opts.s_commit_interval = sbi->s_commit_interval;
6237 	old_opts.s_min_batch_time = sbi->s_min_batch_time;
6238 	old_opts.s_max_batch_time = sbi->s_max_batch_time;
6239 #ifdef CONFIG_QUOTA
6240 	old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6241 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6242 		if (sbi->s_qf_names[i]) {
6243 			char *qf_name = get_qf_name(sb, sbi, i);
6244 
6245 			old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6246 			if (!old_opts.s_qf_names[i]) {
6247 				for (j = 0; j < i; j++)
6248 					kfree(old_opts.s_qf_names[j]);
6249 				return -ENOMEM;
6250 			}
6251 		} else
6252 			old_opts.s_qf_names[i] = NULL;
6253 #endif
6254 	if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6255 		ctx->journal_ioprio =
6256 			sbi->s_journal->j_task->io_context->ioprio;
6257 
6258 	ext4_apply_options(fc, sb);
6259 
6260 	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6261 	    test_opt(sb, JOURNAL_CHECKSUM)) {
6262 		ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6263 			 "during remount not supported; ignoring");
6264 		sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6265 	}
6266 
6267 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6268 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6269 			ext4_msg(sb, KERN_ERR, "can't mount with "
6270 				 "both data=journal and delalloc");
6271 			err = -EINVAL;
6272 			goto restore_opts;
6273 		}
6274 		if (test_opt(sb, DIOREAD_NOLOCK)) {
6275 			ext4_msg(sb, KERN_ERR, "can't mount with "
6276 				 "both data=journal and dioread_nolock");
6277 			err = -EINVAL;
6278 			goto restore_opts;
6279 		}
6280 	} else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6281 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6282 			ext4_msg(sb, KERN_ERR, "can't mount with "
6283 				"journal_async_commit in data=ordered mode");
6284 			err = -EINVAL;
6285 			goto restore_opts;
6286 		}
6287 	}
6288 
6289 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6290 		ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6291 		err = -EINVAL;
6292 		goto restore_opts;
6293 	}
6294 
6295 	if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
6296 		ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6297 
6298 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6299 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6300 
6301 	es = sbi->s_es;
6302 
6303 	if (sbi->s_journal) {
6304 		ext4_init_journal_params(sb, sbi->s_journal);
6305 		set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6306 	}
6307 
6308 	/* Flush outstanding errors before changing fs state */
6309 	flush_work(&sbi->s_error_work);
6310 
6311 	if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6312 		if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
6313 			err = -EROFS;
6314 			goto restore_opts;
6315 		}
6316 
6317 		if (fc->sb_flags & SB_RDONLY) {
6318 			err = sync_filesystem(sb);
6319 			if (err < 0)
6320 				goto restore_opts;
6321 			err = dquot_suspend(sb, -1);
6322 			if (err < 0)
6323 				goto restore_opts;
6324 
6325 			/*
6326 			 * First of all, the unconditional stuff we have to do
6327 			 * to disable replay of the journal when we next remount
6328 			 */
6329 			sb->s_flags |= SB_RDONLY;
6330 
6331 			/*
6332 			 * OK, test if we are remounting a valid rw partition
6333 			 * readonly, and if so set the rdonly flag and then
6334 			 * mark the partition as valid again.
6335 			 */
6336 			if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6337 			    (sbi->s_mount_state & EXT4_VALID_FS))
6338 				es->s_state = cpu_to_le16(sbi->s_mount_state);
6339 
6340 			if (sbi->s_journal) {
6341 				/*
6342 				 * We let remount-ro finish even if marking fs
6343 				 * as clean failed...
6344 				 */
6345 				ext4_mark_recovery_complete(sb, es);
6346 			}
6347 		} else {
6348 			/* Make sure we can mount this feature set readwrite */
6349 			if (ext4_has_feature_readonly(sb) ||
6350 			    !ext4_feature_set_ok(sb, 0)) {
6351 				err = -EROFS;
6352 				goto restore_opts;
6353 			}
6354 			/*
6355 			 * Make sure the group descriptor checksums
6356 			 * are sane.  If they aren't, refuse to remount r/w.
6357 			 */
6358 			for (g = 0; g < sbi->s_groups_count; g++) {
6359 				struct ext4_group_desc *gdp =
6360 					ext4_get_group_desc(sb, g, NULL);
6361 
6362 				if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6363 					ext4_msg(sb, KERN_ERR,
6364 	       "ext4_remount: Checksum for group %u failed (%u!=%u)",
6365 		g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6366 					       le16_to_cpu(gdp->bg_checksum));
6367 					err = -EFSBADCRC;
6368 					goto restore_opts;
6369 				}
6370 			}
6371 
6372 			/*
6373 			 * If we have an unprocessed orphan list hanging
6374 			 * around from a previously readonly bdev mount,
6375 			 * require a full umount/remount for now.
6376 			 */
6377 			if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6378 				ext4_msg(sb, KERN_WARNING, "Couldn't "
6379 				       "remount RDWR because of unprocessed "
6380 				       "orphan inode list.  Please "
6381 				       "umount/remount instead");
6382 				err = -EINVAL;
6383 				goto restore_opts;
6384 			}
6385 
6386 			/*
6387 			 * Mounting a RDONLY partition read-write, so reread
6388 			 * and store the current valid flag.  (It may have
6389 			 * been changed by e2fsck since we originally mounted
6390 			 * the partition.)
6391 			 */
6392 			if (sbi->s_journal) {
6393 				err = ext4_clear_journal_err(sb, es);
6394 				if (err)
6395 					goto restore_opts;
6396 			}
6397 			sbi->s_mount_state = le16_to_cpu(es->s_state);
6398 
6399 			err = ext4_setup_super(sb, es, 0);
6400 			if (err)
6401 				goto restore_opts;
6402 
6403 			sb->s_flags &= ~SB_RDONLY;
6404 			if (ext4_has_feature_mmp(sb))
6405 				if (ext4_multi_mount_protect(sb,
6406 						le64_to_cpu(es->s_mmp_block))) {
6407 					err = -EROFS;
6408 					goto restore_opts;
6409 				}
6410 #ifdef CONFIG_QUOTA
6411 			enable_quota = 1;
6412 #endif
6413 		}
6414 	}
6415 
6416 	/*
6417 	 * Reinitialize lazy itable initialization thread based on
6418 	 * current settings
6419 	 */
6420 	if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6421 		ext4_unregister_li_request(sb);
6422 	else {
6423 		ext4_group_t first_not_zeroed;
6424 		first_not_zeroed = ext4_has_uninit_itable(sb);
6425 		ext4_register_li_request(sb, first_not_zeroed);
6426 	}
6427 
6428 	/*
6429 	 * Handle creation of system zone data early because it can fail.
6430 	 * Releasing of existing data is done when we are sure remount will
6431 	 * succeed.
6432 	 */
6433 	if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6434 		err = ext4_setup_system_zone(sb);
6435 		if (err)
6436 			goto restore_opts;
6437 	}
6438 
6439 	if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6440 		err = ext4_commit_super(sb);
6441 		if (err)
6442 			goto restore_opts;
6443 	}
6444 
6445 #ifdef CONFIG_QUOTA
6446 	/* Release old quota file names */
6447 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6448 		kfree(old_opts.s_qf_names[i]);
6449 	if (enable_quota) {
6450 		if (sb_any_quota_suspended(sb))
6451 			dquot_resume(sb, -1);
6452 		else if (ext4_has_feature_quota(sb)) {
6453 			err = ext4_enable_quotas(sb);
6454 			if (err)
6455 				goto restore_opts;
6456 		}
6457 	}
6458 #endif
6459 	if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6460 		ext4_release_system_zone(sb);
6461 
6462 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6463 		ext4_stop_mmpd(sbi);
6464 
6465 	return 0;
6466 
6467 restore_opts:
6468 	sb->s_flags = old_sb_flags;
6469 	sbi->s_mount_opt = old_opts.s_mount_opt;
6470 	sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6471 	sbi->s_resuid = old_opts.s_resuid;
6472 	sbi->s_resgid = old_opts.s_resgid;
6473 	sbi->s_commit_interval = old_opts.s_commit_interval;
6474 	sbi->s_min_batch_time = old_opts.s_min_batch_time;
6475 	sbi->s_max_batch_time = old_opts.s_max_batch_time;
6476 	if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6477 		ext4_release_system_zone(sb);
6478 #ifdef CONFIG_QUOTA
6479 	sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6480 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6481 		to_free[i] = get_qf_name(sb, sbi, i);
6482 		rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6483 	}
6484 	synchronize_rcu();
6485 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6486 		kfree(to_free[i]);
6487 #endif
6488 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6489 		ext4_stop_mmpd(sbi);
6490 	return err;
6491 }
6492 
6493 static int ext4_reconfigure(struct fs_context *fc)
6494 {
6495 	struct super_block *sb = fc->root->d_sb;
6496 	int ret;
6497 
6498 	fc->s_fs_info = EXT4_SB(sb);
6499 
6500 	ret = ext4_check_opt_consistency(fc, sb);
6501 	if (ret < 0)
6502 		return ret;
6503 
6504 	ret = __ext4_remount(fc, sb);
6505 	if (ret < 0)
6506 		return ret;
6507 
6508 	ext4_msg(sb, KERN_INFO, "re-mounted. Quota mode: %s.",
6509 		 ext4_quota_mode(sb));
6510 
6511 	return 0;
6512 }
6513 
6514 #ifdef CONFIG_QUOTA
6515 static int ext4_statfs_project(struct super_block *sb,
6516 			       kprojid_t projid, struct kstatfs *buf)
6517 {
6518 	struct kqid qid;
6519 	struct dquot *dquot;
6520 	u64 limit;
6521 	u64 curblock;
6522 
6523 	qid = make_kqid_projid(projid);
6524 	dquot = dqget(sb, qid);
6525 	if (IS_ERR(dquot))
6526 		return PTR_ERR(dquot);
6527 	spin_lock(&dquot->dq_dqb_lock);
6528 
6529 	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6530 			     dquot->dq_dqb.dqb_bhardlimit);
6531 	limit >>= sb->s_blocksize_bits;
6532 
6533 	if (limit && buf->f_blocks > limit) {
6534 		curblock = (dquot->dq_dqb.dqb_curspace +
6535 			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6536 		buf->f_blocks = limit;
6537 		buf->f_bfree = buf->f_bavail =
6538 			(buf->f_blocks > curblock) ?
6539 			 (buf->f_blocks - curblock) : 0;
6540 	}
6541 
6542 	limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6543 			     dquot->dq_dqb.dqb_ihardlimit);
6544 	if (limit && buf->f_files > limit) {
6545 		buf->f_files = limit;
6546 		buf->f_ffree =
6547 			(buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6548 			 (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6549 	}
6550 
6551 	spin_unlock(&dquot->dq_dqb_lock);
6552 	dqput(dquot);
6553 	return 0;
6554 }
6555 #endif
6556 
6557 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6558 {
6559 	struct super_block *sb = dentry->d_sb;
6560 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6561 	struct ext4_super_block *es = sbi->s_es;
6562 	ext4_fsblk_t overhead = 0, resv_blocks;
6563 	s64 bfree;
6564 	resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6565 
6566 	if (!test_opt(sb, MINIX_DF))
6567 		overhead = sbi->s_overhead;
6568 
6569 	buf->f_type = EXT4_SUPER_MAGIC;
6570 	buf->f_bsize = sb->s_blocksize;
6571 	buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6572 	bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6573 		percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6574 	/* prevent underflow in case that few free space is available */
6575 	buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6576 	buf->f_bavail = buf->f_bfree -
6577 			(ext4_r_blocks_count(es) + resv_blocks);
6578 	if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6579 		buf->f_bavail = 0;
6580 	buf->f_files = le32_to_cpu(es->s_inodes_count);
6581 	buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6582 	buf->f_namelen = EXT4_NAME_LEN;
6583 	buf->f_fsid = uuid_to_fsid(es->s_uuid);
6584 
6585 #ifdef CONFIG_QUOTA
6586 	if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6587 	    sb_has_quota_limits_enabled(sb, PRJQUOTA))
6588 		ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6589 #endif
6590 	return 0;
6591 }
6592 
6593 
6594 #ifdef CONFIG_QUOTA
6595 
6596 /*
6597  * Helper functions so that transaction is started before we acquire dqio_sem
6598  * to keep correct lock ordering of transaction > dqio_sem
6599  */
6600 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6601 {
6602 	return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6603 }
6604 
6605 static int ext4_write_dquot(struct dquot *dquot)
6606 {
6607 	int ret, err;
6608 	handle_t *handle;
6609 	struct inode *inode;
6610 
6611 	inode = dquot_to_inode(dquot);
6612 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6613 				    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6614 	if (IS_ERR(handle))
6615 		return PTR_ERR(handle);
6616 	ret = dquot_commit(dquot);
6617 	err = ext4_journal_stop(handle);
6618 	if (!ret)
6619 		ret = err;
6620 	return ret;
6621 }
6622 
6623 static int ext4_acquire_dquot(struct dquot *dquot)
6624 {
6625 	int ret, err;
6626 	handle_t *handle;
6627 
6628 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6629 				    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6630 	if (IS_ERR(handle))
6631 		return PTR_ERR(handle);
6632 	ret = dquot_acquire(dquot);
6633 	err = ext4_journal_stop(handle);
6634 	if (!ret)
6635 		ret = err;
6636 	return ret;
6637 }
6638 
6639 static int ext4_release_dquot(struct dquot *dquot)
6640 {
6641 	int ret, err;
6642 	handle_t *handle;
6643 
6644 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6645 				    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6646 	if (IS_ERR(handle)) {
6647 		/* Release dquot anyway to avoid endless cycle in dqput() */
6648 		dquot_release(dquot);
6649 		return PTR_ERR(handle);
6650 	}
6651 	ret = dquot_release(dquot);
6652 	err = ext4_journal_stop(handle);
6653 	if (!ret)
6654 		ret = err;
6655 	return ret;
6656 }
6657 
6658 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6659 {
6660 	struct super_block *sb = dquot->dq_sb;
6661 
6662 	if (ext4_is_quota_journalled(sb)) {
6663 		dquot_mark_dquot_dirty(dquot);
6664 		return ext4_write_dquot(dquot);
6665 	} else {
6666 		return dquot_mark_dquot_dirty(dquot);
6667 	}
6668 }
6669 
6670 static int ext4_write_info(struct super_block *sb, int type)
6671 {
6672 	int ret, err;
6673 	handle_t *handle;
6674 
6675 	/* Data block + inode block */
6676 	handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6677 	if (IS_ERR(handle))
6678 		return PTR_ERR(handle);
6679 	ret = dquot_commit_info(sb, type);
6680 	err = ext4_journal_stop(handle);
6681 	if (!ret)
6682 		ret = err;
6683 	return ret;
6684 }
6685 
6686 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6687 {
6688 	struct ext4_inode_info *ei = EXT4_I(inode);
6689 
6690 	/* The first argument of lockdep_set_subclass has to be
6691 	 * *exactly* the same as the argument to init_rwsem() --- in
6692 	 * this case, in init_once() --- or lockdep gets unhappy
6693 	 * because the name of the lock is set using the
6694 	 * stringification of the argument to init_rwsem().
6695 	 */
6696 	(void) ei;	/* shut up clang warning if !CONFIG_LOCKDEP */
6697 	lockdep_set_subclass(&ei->i_data_sem, subclass);
6698 }
6699 
6700 /*
6701  * Standard function to be called on quota_on
6702  */
6703 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6704 			 const struct path *path)
6705 {
6706 	int err;
6707 
6708 	if (!test_opt(sb, QUOTA))
6709 		return -EINVAL;
6710 
6711 	/* Quotafile not on the same filesystem? */
6712 	if (path->dentry->d_sb != sb)
6713 		return -EXDEV;
6714 
6715 	/* Quota already enabled for this file? */
6716 	if (IS_NOQUOTA(d_inode(path->dentry)))
6717 		return -EBUSY;
6718 
6719 	/* Journaling quota? */
6720 	if (EXT4_SB(sb)->s_qf_names[type]) {
6721 		/* Quotafile not in fs root? */
6722 		if (path->dentry->d_parent != sb->s_root)
6723 			ext4_msg(sb, KERN_WARNING,
6724 				"Quota file not on filesystem root. "
6725 				"Journaled quota will not work");
6726 		sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6727 	} else {
6728 		/*
6729 		 * Clear the flag just in case mount options changed since
6730 		 * last time.
6731 		 */
6732 		sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6733 	}
6734 
6735 	/*
6736 	 * When we journal data on quota file, we have to flush journal to see
6737 	 * all updates to the file when we bypass pagecache...
6738 	 */
6739 	if (EXT4_SB(sb)->s_journal &&
6740 	    ext4_should_journal_data(d_inode(path->dentry))) {
6741 		/*
6742 		 * We don't need to lock updates but journal_flush() could
6743 		 * otherwise be livelocked...
6744 		 */
6745 		jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6746 		err = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
6747 		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6748 		if (err)
6749 			return err;
6750 	}
6751 
6752 	lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6753 	err = dquot_quota_on(sb, type, format_id, path);
6754 	if (!err) {
6755 		struct inode *inode = d_inode(path->dentry);
6756 		handle_t *handle;
6757 
6758 		/*
6759 		 * Set inode flags to prevent userspace from messing with quota
6760 		 * files. If this fails, we return success anyway since quotas
6761 		 * are already enabled and this is not a hard failure.
6762 		 */
6763 		inode_lock(inode);
6764 		handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6765 		if (IS_ERR(handle))
6766 			goto unlock_inode;
6767 		EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6768 		inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6769 				S_NOATIME | S_IMMUTABLE);
6770 		err = ext4_mark_inode_dirty(handle, inode);
6771 		ext4_journal_stop(handle);
6772 	unlock_inode:
6773 		inode_unlock(inode);
6774 		if (err)
6775 			dquot_quota_off(sb, type);
6776 	}
6777 	if (err)
6778 		lockdep_set_quota_inode(path->dentry->d_inode,
6779 					     I_DATA_SEM_NORMAL);
6780 	return err;
6781 }
6782 
6783 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6784 			     unsigned int flags)
6785 {
6786 	int err;
6787 	struct inode *qf_inode;
6788 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6789 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6790 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6791 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6792 	};
6793 
6794 	BUG_ON(!ext4_has_feature_quota(sb));
6795 
6796 	if (!qf_inums[type])
6797 		return -EPERM;
6798 
6799 	qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6800 	if (IS_ERR(qf_inode)) {
6801 		ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6802 		return PTR_ERR(qf_inode);
6803 	}
6804 
6805 	/* Don't account quota for quota files to avoid recursion */
6806 	qf_inode->i_flags |= S_NOQUOTA;
6807 	lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6808 	err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6809 	if (err)
6810 		lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6811 	iput(qf_inode);
6812 
6813 	return err;
6814 }
6815 
6816 /* Enable usage tracking for all quota types. */
6817 int ext4_enable_quotas(struct super_block *sb)
6818 {
6819 	int type, err = 0;
6820 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6821 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6822 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6823 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6824 	};
6825 	bool quota_mopt[EXT4_MAXQUOTAS] = {
6826 		test_opt(sb, USRQUOTA),
6827 		test_opt(sb, GRPQUOTA),
6828 		test_opt(sb, PRJQUOTA),
6829 	};
6830 
6831 	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6832 	for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6833 		if (qf_inums[type]) {
6834 			err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6835 				DQUOT_USAGE_ENABLED |
6836 				(quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6837 			if (err) {
6838 				ext4_warning(sb,
6839 					"Failed to enable quota tracking "
6840 					"(type=%d, err=%d). Please run "
6841 					"e2fsck to fix.", type, err);
6842 				for (type--; type >= 0; type--) {
6843 					struct inode *inode;
6844 
6845 					inode = sb_dqopt(sb)->files[type];
6846 					if (inode)
6847 						inode = igrab(inode);
6848 					dquot_quota_off(sb, type);
6849 					if (inode) {
6850 						lockdep_set_quota_inode(inode,
6851 							I_DATA_SEM_NORMAL);
6852 						iput(inode);
6853 					}
6854 				}
6855 
6856 				return err;
6857 			}
6858 		}
6859 	}
6860 	return 0;
6861 }
6862 
6863 static int ext4_quota_off(struct super_block *sb, int type)
6864 {
6865 	struct inode *inode = sb_dqopt(sb)->files[type];
6866 	handle_t *handle;
6867 	int err;
6868 
6869 	/* Force all delayed allocation blocks to be allocated.
6870 	 * Caller already holds s_umount sem */
6871 	if (test_opt(sb, DELALLOC))
6872 		sync_filesystem(sb);
6873 
6874 	if (!inode || !igrab(inode))
6875 		goto out;
6876 
6877 	err = dquot_quota_off(sb, type);
6878 	if (err || ext4_has_feature_quota(sb))
6879 		goto out_put;
6880 
6881 	inode_lock(inode);
6882 	/*
6883 	 * Update modification times of quota files when userspace can
6884 	 * start looking at them. If we fail, we return success anyway since
6885 	 * this is not a hard failure and quotas are already disabled.
6886 	 */
6887 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6888 	if (IS_ERR(handle)) {
6889 		err = PTR_ERR(handle);
6890 		goto out_unlock;
6891 	}
6892 	EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6893 	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6894 	inode->i_mtime = inode->i_ctime = current_time(inode);
6895 	err = ext4_mark_inode_dirty(handle, inode);
6896 	ext4_journal_stop(handle);
6897 out_unlock:
6898 	inode_unlock(inode);
6899 out_put:
6900 	lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6901 	iput(inode);
6902 	return err;
6903 out:
6904 	return dquot_quota_off(sb, type);
6905 }
6906 
6907 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6908  * acquiring the locks... As quota files are never truncated and quota code
6909  * itself serializes the operations (and no one else should touch the files)
6910  * we don't have to be afraid of races */
6911 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6912 			       size_t len, loff_t off)
6913 {
6914 	struct inode *inode = sb_dqopt(sb)->files[type];
6915 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6916 	int offset = off & (sb->s_blocksize - 1);
6917 	int tocopy;
6918 	size_t toread;
6919 	struct buffer_head *bh;
6920 	loff_t i_size = i_size_read(inode);
6921 
6922 	if (off > i_size)
6923 		return 0;
6924 	if (off+len > i_size)
6925 		len = i_size-off;
6926 	toread = len;
6927 	while (toread > 0) {
6928 		tocopy = sb->s_blocksize - offset < toread ?
6929 				sb->s_blocksize - offset : toread;
6930 		bh = ext4_bread(NULL, inode, blk, 0);
6931 		if (IS_ERR(bh))
6932 			return PTR_ERR(bh);
6933 		if (!bh)	/* A hole? */
6934 			memset(data, 0, tocopy);
6935 		else
6936 			memcpy(data, bh->b_data+offset, tocopy);
6937 		brelse(bh);
6938 		offset = 0;
6939 		toread -= tocopy;
6940 		data += tocopy;
6941 		blk++;
6942 	}
6943 	return len;
6944 }
6945 
6946 /* Write to quotafile (we know the transaction is already started and has
6947  * enough credits) */
6948 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6949 				const char *data, size_t len, loff_t off)
6950 {
6951 	struct inode *inode = sb_dqopt(sb)->files[type];
6952 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6953 	int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6954 	int retries = 0;
6955 	struct buffer_head *bh;
6956 	handle_t *handle = journal_current_handle();
6957 
6958 	if (!handle) {
6959 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6960 			" cancelled because transaction is not started",
6961 			(unsigned long long)off, (unsigned long long)len);
6962 		return -EIO;
6963 	}
6964 	/*
6965 	 * Since we account only one data block in transaction credits,
6966 	 * then it is impossible to cross a block boundary.
6967 	 */
6968 	if (sb->s_blocksize - offset < len) {
6969 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6970 			" cancelled because not block aligned",
6971 			(unsigned long long)off, (unsigned long long)len);
6972 		return -EIO;
6973 	}
6974 
6975 	do {
6976 		bh = ext4_bread(handle, inode, blk,
6977 				EXT4_GET_BLOCKS_CREATE |
6978 				EXT4_GET_BLOCKS_METADATA_NOFAIL);
6979 	} while (PTR_ERR(bh) == -ENOSPC &&
6980 		 ext4_should_retry_alloc(inode->i_sb, &retries));
6981 	if (IS_ERR(bh))
6982 		return PTR_ERR(bh);
6983 	if (!bh)
6984 		goto out;
6985 	BUFFER_TRACE(bh, "get write access");
6986 	err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
6987 	if (err) {
6988 		brelse(bh);
6989 		return err;
6990 	}
6991 	lock_buffer(bh);
6992 	memcpy(bh->b_data+offset, data, len);
6993 	flush_dcache_page(bh->b_page);
6994 	unlock_buffer(bh);
6995 	err = ext4_handle_dirty_metadata(handle, NULL, bh);
6996 	brelse(bh);
6997 out:
6998 	if (inode->i_size < off + len) {
6999 		i_size_write(inode, off + len);
7000 		EXT4_I(inode)->i_disksize = inode->i_size;
7001 		err2 = ext4_mark_inode_dirty(handle, inode);
7002 		if (unlikely(err2 && !err))
7003 			err = err2;
7004 	}
7005 	return err ? err : len;
7006 }
7007 #endif
7008 
7009 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7010 static inline void register_as_ext2(void)
7011 {
7012 	int err = register_filesystem(&ext2_fs_type);
7013 	if (err)
7014 		printk(KERN_WARNING
7015 		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7016 }
7017 
7018 static inline void unregister_as_ext2(void)
7019 {
7020 	unregister_filesystem(&ext2_fs_type);
7021 }
7022 
7023 static inline int ext2_feature_set_ok(struct super_block *sb)
7024 {
7025 	if (ext4_has_unknown_ext2_incompat_features(sb))
7026 		return 0;
7027 	if (sb_rdonly(sb))
7028 		return 1;
7029 	if (ext4_has_unknown_ext2_ro_compat_features(sb))
7030 		return 0;
7031 	return 1;
7032 }
7033 #else
7034 static inline void register_as_ext2(void) { }
7035 static inline void unregister_as_ext2(void) { }
7036 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7037 #endif
7038 
7039 static inline void register_as_ext3(void)
7040 {
7041 	int err = register_filesystem(&ext3_fs_type);
7042 	if (err)
7043 		printk(KERN_WARNING
7044 		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7045 }
7046 
7047 static inline void unregister_as_ext3(void)
7048 {
7049 	unregister_filesystem(&ext3_fs_type);
7050 }
7051 
7052 static inline int ext3_feature_set_ok(struct super_block *sb)
7053 {
7054 	if (ext4_has_unknown_ext3_incompat_features(sb))
7055 		return 0;
7056 	if (!ext4_has_feature_journal(sb))
7057 		return 0;
7058 	if (sb_rdonly(sb))
7059 		return 1;
7060 	if (ext4_has_unknown_ext3_ro_compat_features(sb))
7061 		return 0;
7062 	return 1;
7063 }
7064 
7065 static struct file_system_type ext4_fs_type = {
7066 	.owner			= THIS_MODULE,
7067 	.name			= "ext4",
7068 	.init_fs_context	= ext4_init_fs_context,
7069 	.parameters		= ext4_param_specs,
7070 	.kill_sb		= kill_block_super,
7071 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7072 };
7073 MODULE_ALIAS_FS("ext4");
7074 
7075 /* Shared across all ext4 file systems */
7076 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7077 
7078 static int __init ext4_init_fs(void)
7079 {
7080 	int i, err;
7081 
7082 	ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7083 	ext4_li_info = NULL;
7084 
7085 	/* Build-time check for flags consistency */
7086 	ext4_check_flag_values();
7087 
7088 	for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7089 		init_waitqueue_head(&ext4__ioend_wq[i]);
7090 
7091 	err = ext4_init_es();
7092 	if (err)
7093 		return err;
7094 
7095 	err = ext4_init_pending();
7096 	if (err)
7097 		goto out7;
7098 
7099 	err = ext4_init_post_read_processing();
7100 	if (err)
7101 		goto out6;
7102 
7103 	err = ext4_init_pageio();
7104 	if (err)
7105 		goto out5;
7106 
7107 	err = ext4_init_system_zone();
7108 	if (err)
7109 		goto out4;
7110 
7111 	err = ext4_init_sysfs();
7112 	if (err)
7113 		goto out3;
7114 
7115 	err = ext4_init_mballoc();
7116 	if (err)
7117 		goto out2;
7118 	err = init_inodecache();
7119 	if (err)
7120 		goto out1;
7121 
7122 	err = ext4_fc_init_dentry_cache();
7123 	if (err)
7124 		goto out05;
7125 
7126 	register_as_ext3();
7127 	register_as_ext2();
7128 	err = register_filesystem(&ext4_fs_type);
7129 	if (err)
7130 		goto out;
7131 
7132 	return 0;
7133 out:
7134 	unregister_as_ext2();
7135 	unregister_as_ext3();
7136 	ext4_fc_destroy_dentry_cache();
7137 out05:
7138 	destroy_inodecache();
7139 out1:
7140 	ext4_exit_mballoc();
7141 out2:
7142 	ext4_exit_sysfs();
7143 out3:
7144 	ext4_exit_system_zone();
7145 out4:
7146 	ext4_exit_pageio();
7147 out5:
7148 	ext4_exit_post_read_processing();
7149 out6:
7150 	ext4_exit_pending();
7151 out7:
7152 	ext4_exit_es();
7153 
7154 	return err;
7155 }
7156 
7157 static void __exit ext4_exit_fs(void)
7158 {
7159 	ext4_destroy_lazyinit_thread();
7160 	unregister_as_ext2();
7161 	unregister_as_ext3();
7162 	unregister_filesystem(&ext4_fs_type);
7163 	ext4_fc_destroy_dentry_cache();
7164 	destroy_inodecache();
7165 	ext4_exit_mballoc();
7166 	ext4_exit_sysfs();
7167 	ext4_exit_system_zone();
7168 	ext4_exit_pageio();
7169 	ext4_exit_post_read_processing();
7170 	ext4_exit_es();
7171 	ext4_exit_pending();
7172 }
7173 
7174 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7175 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7176 MODULE_LICENSE("GPL");
7177 MODULE_SOFTDEP("pre: crc32c");
7178 module_init(ext4_init_fs)
7179 module_exit(ext4_exit_fs)
7180