xref: /openbmc/linux/fs/ext4/super.c (revision 34fa67e7)
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/cleancache.h>
43 #include <linux/uaccess.h>
44 #include <linux/iversion.h>
45 #include <linux/unicode.h>
46 #include <linux/part_stat.h>
47 #include <linux/kthread.h>
48 #include <linux/freezer.h>
49 #include <linux/fsnotify.h>
50 #include <linux/fs_context.h>
51 #include <linux/fs_parser.h>
52 
53 #include "ext4.h"
54 #include "ext4_extents.h"	/* Needed for trace points definition */
55 #include "ext4_jbd2.h"
56 #include "xattr.h"
57 #include "acl.h"
58 #include "mballoc.h"
59 #include "fsmap.h"
60 
61 #define CREATE_TRACE_POINTS
62 #include <trace/events/ext4.h>
63 
64 static struct ext4_lazy_init *ext4_li_info;
65 static DEFINE_MUTEX(ext4_li_mtx);
66 static struct ratelimit_state ext4_mount_msg_ratelimit;
67 
68 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
69 			     unsigned long journal_devnum);
70 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
71 static void ext4_update_super(struct super_block *sb);
72 static int ext4_commit_super(struct super_block *sb);
73 static int ext4_mark_recovery_complete(struct super_block *sb,
74 					struct ext4_super_block *es);
75 static int ext4_clear_journal_err(struct super_block *sb,
76 				  struct ext4_super_block *es);
77 static int ext4_sync_fs(struct super_block *sb, int wait);
78 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
79 static int ext4_unfreeze(struct super_block *sb);
80 static int ext4_freeze(struct super_block *sb);
81 static inline int ext2_feature_set_ok(struct super_block *sb);
82 static inline int ext3_feature_set_ok(struct super_block *sb);
83 static void ext4_destroy_lazyinit_thread(void);
84 static void ext4_unregister_li_request(struct super_block *sb);
85 static void ext4_clear_request_list(void);
86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
87 					    unsigned int journal_inum);
88 static int ext4_validate_options(struct fs_context *fc);
89 static int ext4_check_opt_consistency(struct fs_context *fc,
90 				      struct super_block *sb);
91 static int ext4_apply_options(struct fs_context *fc, struct super_block *sb);
92 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
93 static int ext4_get_tree(struct fs_context *fc);
94 static int ext4_reconfigure(struct fs_context *fc);
95 static void ext4_fc_free(struct fs_context *fc);
96 static int ext4_init_fs_context(struct fs_context *fc);
97 static const struct fs_parameter_spec ext4_param_specs[];
98 
99 /*
100  * Lock ordering
101  *
102  * page fault path:
103  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
104  *   -> page lock -> i_data_sem (rw)
105  *
106  * buffered write path:
107  * sb_start_write -> i_mutex -> mmap_lock
108  * sb_start_write -> i_mutex -> transaction start -> page lock ->
109  *   i_data_sem (rw)
110  *
111  * truncate:
112  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
113  *   page lock
114  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
115  *   i_data_sem (rw)
116  *
117  * direct IO:
118  * sb_start_write -> i_mutex -> mmap_lock
119  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
120  *
121  * writepages:
122  * transaction start -> page lock(s) -> i_data_sem (rw)
123  */
124 
125 static const struct fs_context_operations ext4_context_ops = {
126 	.parse_param	= ext4_parse_param,
127 	.get_tree	= ext4_get_tree,
128 	.reconfigure	= ext4_reconfigure,
129 	.free		= ext4_fc_free,
130 };
131 
132 
133 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
134 static struct file_system_type ext2_fs_type = {
135 	.owner			= THIS_MODULE,
136 	.name			= "ext2",
137 	.init_fs_context	= ext4_init_fs_context,
138 	.parameters		= ext4_param_specs,
139 	.kill_sb		= kill_block_super,
140 	.fs_flags		= FS_REQUIRES_DEV,
141 };
142 MODULE_ALIAS_FS("ext2");
143 MODULE_ALIAS("ext2");
144 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
145 #else
146 #define IS_EXT2_SB(sb) (0)
147 #endif
148 
149 
150 static struct file_system_type ext3_fs_type = {
151 	.owner			= THIS_MODULE,
152 	.name			= "ext3",
153 	.init_fs_context	= ext4_init_fs_context,
154 	.parameters		= ext4_param_specs,
155 	.kill_sb		= kill_block_super,
156 	.fs_flags		= FS_REQUIRES_DEV,
157 };
158 MODULE_ALIAS_FS("ext3");
159 MODULE_ALIAS("ext3");
160 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
161 
162 
163 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
164 				  bh_end_io_t *end_io)
165 {
166 	/*
167 	 * buffer's verified bit is no longer valid after reading from
168 	 * disk again due to write out error, clear it to make sure we
169 	 * recheck the buffer contents.
170 	 */
171 	clear_buffer_verified(bh);
172 
173 	bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
174 	get_bh(bh);
175 	submit_bh(REQ_OP_READ, op_flags, bh);
176 }
177 
178 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
179 			 bh_end_io_t *end_io)
180 {
181 	BUG_ON(!buffer_locked(bh));
182 
183 	if (ext4_buffer_uptodate(bh)) {
184 		unlock_buffer(bh);
185 		return;
186 	}
187 	__ext4_read_bh(bh, op_flags, end_io);
188 }
189 
190 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
191 {
192 	BUG_ON(!buffer_locked(bh));
193 
194 	if (ext4_buffer_uptodate(bh)) {
195 		unlock_buffer(bh);
196 		return 0;
197 	}
198 
199 	__ext4_read_bh(bh, op_flags, end_io);
200 
201 	wait_on_buffer(bh);
202 	if (buffer_uptodate(bh))
203 		return 0;
204 	return -EIO;
205 }
206 
207 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
208 {
209 	if (trylock_buffer(bh)) {
210 		if (wait)
211 			return ext4_read_bh(bh, op_flags, NULL);
212 		ext4_read_bh_nowait(bh, op_flags, NULL);
213 		return 0;
214 	}
215 	if (wait) {
216 		wait_on_buffer(bh);
217 		if (buffer_uptodate(bh))
218 			return 0;
219 		return -EIO;
220 	}
221 	return 0;
222 }
223 
224 /*
225  * This works like __bread_gfp() except it uses ERR_PTR for error
226  * returns.  Currently with sb_bread it's impossible to distinguish
227  * between ENOMEM and EIO situations (since both result in a NULL
228  * return.
229  */
230 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
231 					       sector_t block, int op_flags,
232 					       gfp_t gfp)
233 {
234 	struct buffer_head *bh;
235 	int ret;
236 
237 	bh = sb_getblk_gfp(sb, block, gfp);
238 	if (bh == NULL)
239 		return ERR_PTR(-ENOMEM);
240 	if (ext4_buffer_uptodate(bh))
241 		return bh;
242 
243 	ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
244 	if (ret) {
245 		put_bh(bh);
246 		return ERR_PTR(ret);
247 	}
248 	return bh;
249 }
250 
251 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
252 				   int op_flags)
253 {
254 	return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
255 }
256 
257 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
258 					    sector_t block)
259 {
260 	return __ext4_sb_bread_gfp(sb, block, 0, 0);
261 }
262 
263 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
264 {
265 	struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
266 
267 	if (likely(bh)) {
268 		ext4_read_bh_lock(bh, REQ_RAHEAD, false);
269 		brelse(bh);
270 	}
271 }
272 
273 static int ext4_verify_csum_type(struct super_block *sb,
274 				 struct ext4_super_block *es)
275 {
276 	if (!ext4_has_feature_metadata_csum(sb))
277 		return 1;
278 
279 	return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
280 }
281 
282 __le32 ext4_superblock_csum(struct super_block *sb,
283 			    struct ext4_super_block *es)
284 {
285 	struct ext4_sb_info *sbi = EXT4_SB(sb);
286 	int offset = offsetof(struct ext4_super_block, s_checksum);
287 	__u32 csum;
288 
289 	csum = ext4_chksum(sbi, ~0, (char *)es, offset);
290 
291 	return cpu_to_le32(csum);
292 }
293 
294 static int ext4_superblock_csum_verify(struct super_block *sb,
295 				       struct ext4_super_block *es)
296 {
297 	if (!ext4_has_metadata_csum(sb))
298 		return 1;
299 
300 	return es->s_checksum == ext4_superblock_csum(sb, es);
301 }
302 
303 void ext4_superblock_csum_set(struct super_block *sb)
304 {
305 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
306 
307 	if (!ext4_has_metadata_csum(sb))
308 		return;
309 
310 	es->s_checksum = ext4_superblock_csum(sb, es);
311 }
312 
313 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
314 			       struct ext4_group_desc *bg)
315 {
316 	return le32_to_cpu(bg->bg_block_bitmap_lo) |
317 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
318 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
319 }
320 
321 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
322 			       struct ext4_group_desc *bg)
323 {
324 	return le32_to_cpu(bg->bg_inode_bitmap_lo) |
325 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
326 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
327 }
328 
329 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
330 			      struct ext4_group_desc *bg)
331 {
332 	return le32_to_cpu(bg->bg_inode_table_lo) |
333 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
334 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
335 }
336 
337 __u32 ext4_free_group_clusters(struct super_block *sb,
338 			       struct ext4_group_desc *bg)
339 {
340 	return le16_to_cpu(bg->bg_free_blocks_count_lo) |
341 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
342 		 (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
343 }
344 
345 __u32 ext4_free_inodes_count(struct super_block *sb,
346 			      struct ext4_group_desc *bg)
347 {
348 	return le16_to_cpu(bg->bg_free_inodes_count_lo) |
349 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
350 		 (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
351 }
352 
353 __u32 ext4_used_dirs_count(struct super_block *sb,
354 			      struct ext4_group_desc *bg)
355 {
356 	return le16_to_cpu(bg->bg_used_dirs_count_lo) |
357 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
358 		 (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
359 }
360 
361 __u32 ext4_itable_unused_count(struct super_block *sb,
362 			      struct ext4_group_desc *bg)
363 {
364 	return le16_to_cpu(bg->bg_itable_unused_lo) |
365 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
366 		 (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
367 }
368 
369 void ext4_block_bitmap_set(struct super_block *sb,
370 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
371 {
372 	bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
373 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
374 		bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
375 }
376 
377 void ext4_inode_bitmap_set(struct super_block *sb,
378 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
379 {
380 	bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
381 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
382 		bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
383 }
384 
385 void ext4_inode_table_set(struct super_block *sb,
386 			  struct ext4_group_desc *bg, ext4_fsblk_t blk)
387 {
388 	bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
389 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
390 		bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
391 }
392 
393 void ext4_free_group_clusters_set(struct super_block *sb,
394 				  struct ext4_group_desc *bg, __u32 count)
395 {
396 	bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
397 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
398 		bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
399 }
400 
401 void ext4_free_inodes_set(struct super_block *sb,
402 			  struct ext4_group_desc *bg, __u32 count)
403 {
404 	bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
405 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
406 		bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
407 }
408 
409 void ext4_used_dirs_set(struct super_block *sb,
410 			  struct ext4_group_desc *bg, __u32 count)
411 {
412 	bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
413 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
414 		bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
415 }
416 
417 void ext4_itable_unused_set(struct super_block *sb,
418 			  struct ext4_group_desc *bg, __u32 count)
419 {
420 	bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
421 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
422 		bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
423 }
424 
425 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
426 {
427 	now = clamp_val(now, 0, (1ull << 40) - 1);
428 
429 	*lo = cpu_to_le32(lower_32_bits(now));
430 	*hi = upper_32_bits(now);
431 }
432 
433 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
434 {
435 	return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
436 }
437 #define ext4_update_tstamp(es, tstamp) \
438 	__ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
439 			     ktime_get_real_seconds())
440 #define ext4_get_tstamp(es, tstamp) \
441 	__ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
442 
443 /*
444  * The del_gendisk() function uninitializes the disk-specific data
445  * structures, including the bdi structure, without telling anyone
446  * else.  Once this happens, any attempt to call mark_buffer_dirty()
447  * (for example, by ext4_commit_super), will cause a kernel OOPS.
448  * This is a kludge to prevent these oops until we can put in a proper
449  * hook in del_gendisk() to inform the VFS and file system layers.
450  */
451 static int block_device_ejected(struct super_block *sb)
452 {
453 	struct inode *bd_inode = sb->s_bdev->bd_inode;
454 	struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
455 
456 	return bdi->dev == NULL;
457 }
458 
459 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
460 {
461 	struct super_block		*sb = journal->j_private;
462 	struct ext4_sb_info		*sbi = EXT4_SB(sb);
463 	int				error = is_journal_aborted(journal);
464 	struct ext4_journal_cb_entry	*jce;
465 
466 	BUG_ON(txn->t_state == T_FINISHED);
467 
468 	ext4_process_freed_data(sb, txn->t_tid);
469 
470 	spin_lock(&sbi->s_md_lock);
471 	while (!list_empty(&txn->t_private_list)) {
472 		jce = list_entry(txn->t_private_list.next,
473 				 struct ext4_journal_cb_entry, jce_list);
474 		list_del_init(&jce->jce_list);
475 		spin_unlock(&sbi->s_md_lock);
476 		jce->jce_func(sb, jce, error);
477 		spin_lock(&sbi->s_md_lock);
478 	}
479 	spin_unlock(&sbi->s_md_lock);
480 }
481 
482 /*
483  * This writepage callback for write_cache_pages()
484  * takes care of a few cases after page cleaning.
485  *
486  * write_cache_pages() already checks for dirty pages
487  * and calls clear_page_dirty_for_io(), which we want,
488  * to write protect the pages.
489  *
490  * However, we may have to redirty a page (see below.)
491  */
492 static int ext4_journalled_writepage_callback(struct page *page,
493 					      struct writeback_control *wbc,
494 					      void *data)
495 {
496 	transaction_t *transaction = (transaction_t *) data;
497 	struct buffer_head *bh, *head;
498 	struct journal_head *jh;
499 
500 	bh = head = page_buffers(page);
501 	do {
502 		/*
503 		 * We have to redirty a page in these cases:
504 		 * 1) If buffer is dirty, it means the page was dirty because it
505 		 * contains a buffer that needs checkpointing. So the dirty bit
506 		 * needs to be preserved so that checkpointing writes the buffer
507 		 * properly.
508 		 * 2) If buffer is not part of the committing transaction
509 		 * (we may have just accidentally come across this buffer because
510 		 * inode range tracking is not exact) or if the currently running
511 		 * transaction already contains this buffer as well, dirty bit
512 		 * needs to be preserved so that the buffer gets writeprotected
513 		 * properly on running transaction's commit.
514 		 */
515 		jh = bh2jh(bh);
516 		if (buffer_dirty(bh) ||
517 		    (jh && (jh->b_transaction != transaction ||
518 			    jh->b_next_transaction))) {
519 			redirty_page_for_writepage(wbc, page);
520 			goto out;
521 		}
522 	} while ((bh = bh->b_this_page) != head);
523 
524 out:
525 	return AOP_WRITEPAGE_ACTIVATE;
526 }
527 
528 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
529 {
530 	struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
531 	struct writeback_control wbc = {
532 		.sync_mode =  WB_SYNC_ALL,
533 		.nr_to_write = LONG_MAX,
534 		.range_start = jinode->i_dirty_start,
535 		.range_end = jinode->i_dirty_end,
536         };
537 
538 	return write_cache_pages(mapping, &wbc,
539 				 ext4_journalled_writepage_callback,
540 				 jinode->i_transaction);
541 }
542 
543 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
544 {
545 	int ret;
546 
547 	if (ext4_should_journal_data(jinode->i_vfs_inode))
548 		ret = ext4_journalled_submit_inode_data_buffers(jinode);
549 	else
550 		ret = jbd2_journal_submit_inode_data_buffers(jinode);
551 
552 	return ret;
553 }
554 
555 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
556 {
557 	int ret = 0;
558 
559 	if (!ext4_should_journal_data(jinode->i_vfs_inode))
560 		ret = jbd2_journal_finish_inode_data_buffers(jinode);
561 
562 	return ret;
563 }
564 
565 static bool system_going_down(void)
566 {
567 	return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
568 		|| system_state == SYSTEM_RESTART;
569 }
570 
571 struct ext4_err_translation {
572 	int code;
573 	int errno;
574 };
575 
576 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
577 
578 static struct ext4_err_translation err_translation[] = {
579 	EXT4_ERR_TRANSLATE(EIO),
580 	EXT4_ERR_TRANSLATE(ENOMEM),
581 	EXT4_ERR_TRANSLATE(EFSBADCRC),
582 	EXT4_ERR_TRANSLATE(EFSCORRUPTED),
583 	EXT4_ERR_TRANSLATE(ENOSPC),
584 	EXT4_ERR_TRANSLATE(ENOKEY),
585 	EXT4_ERR_TRANSLATE(EROFS),
586 	EXT4_ERR_TRANSLATE(EFBIG),
587 	EXT4_ERR_TRANSLATE(EEXIST),
588 	EXT4_ERR_TRANSLATE(ERANGE),
589 	EXT4_ERR_TRANSLATE(EOVERFLOW),
590 	EXT4_ERR_TRANSLATE(EBUSY),
591 	EXT4_ERR_TRANSLATE(ENOTDIR),
592 	EXT4_ERR_TRANSLATE(ENOTEMPTY),
593 	EXT4_ERR_TRANSLATE(ESHUTDOWN),
594 	EXT4_ERR_TRANSLATE(EFAULT),
595 };
596 
597 static int ext4_errno_to_code(int errno)
598 {
599 	int i;
600 
601 	for (i = 0; i < ARRAY_SIZE(err_translation); i++)
602 		if (err_translation[i].errno == errno)
603 			return err_translation[i].code;
604 	return EXT4_ERR_UNKNOWN;
605 }
606 
607 static void save_error_info(struct super_block *sb, int error,
608 			    __u32 ino, __u64 block,
609 			    const char *func, unsigned int line)
610 {
611 	struct ext4_sb_info *sbi = EXT4_SB(sb);
612 
613 	/* We default to EFSCORRUPTED error... */
614 	if (error == 0)
615 		error = EFSCORRUPTED;
616 
617 	spin_lock(&sbi->s_error_lock);
618 	sbi->s_add_error_count++;
619 	sbi->s_last_error_code = error;
620 	sbi->s_last_error_line = line;
621 	sbi->s_last_error_ino = ino;
622 	sbi->s_last_error_block = block;
623 	sbi->s_last_error_func = func;
624 	sbi->s_last_error_time = ktime_get_real_seconds();
625 	if (!sbi->s_first_error_time) {
626 		sbi->s_first_error_code = error;
627 		sbi->s_first_error_line = line;
628 		sbi->s_first_error_ino = ino;
629 		sbi->s_first_error_block = block;
630 		sbi->s_first_error_func = func;
631 		sbi->s_first_error_time = sbi->s_last_error_time;
632 	}
633 	spin_unlock(&sbi->s_error_lock);
634 }
635 
636 /* Deal with the reporting of failure conditions on a filesystem such as
637  * inconsistencies detected or read IO failures.
638  *
639  * On ext2, we can store the error state of the filesystem in the
640  * superblock.  That is not possible on ext4, because we may have other
641  * write ordering constraints on the superblock which prevent us from
642  * writing it out straight away; and given that the journal is about to
643  * be aborted, we can't rely on the current, or future, transactions to
644  * write out the superblock safely.
645  *
646  * We'll just use the jbd2_journal_abort() error code to record an error in
647  * the journal instead.  On recovery, the journal will complain about
648  * that error until we've noted it down and cleared it.
649  *
650  * If force_ro is set, we unconditionally force the filesystem into an
651  * ABORT|READONLY state, unless the error response on the fs has been set to
652  * panic in which case we take the easy way out and panic immediately. This is
653  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
654  * at a critical moment in log management.
655  */
656 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
657 			      __u32 ino, __u64 block,
658 			      const char *func, unsigned int line)
659 {
660 	journal_t *journal = EXT4_SB(sb)->s_journal;
661 	bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
662 
663 	EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
664 	if (test_opt(sb, WARN_ON_ERROR))
665 		WARN_ON_ONCE(1);
666 
667 	if (!continue_fs && !sb_rdonly(sb)) {
668 		ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
669 		if (journal)
670 			jbd2_journal_abort(journal, -EIO);
671 	}
672 
673 	if (!bdev_read_only(sb->s_bdev)) {
674 		save_error_info(sb, error, ino, block, func, line);
675 		/*
676 		 * In case the fs should keep running, we need to writeout
677 		 * superblock through the journal. Due to lock ordering
678 		 * constraints, it may not be safe to do it right here so we
679 		 * defer superblock flushing to a workqueue.
680 		 */
681 		if (continue_fs && journal)
682 			schedule_work(&EXT4_SB(sb)->s_error_work);
683 		else
684 			ext4_commit_super(sb);
685 	}
686 
687 	/*
688 	 * We force ERRORS_RO behavior when system is rebooting. Otherwise we
689 	 * could panic during 'reboot -f' as the underlying device got already
690 	 * disabled.
691 	 */
692 	if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
693 		panic("EXT4-fs (device %s): panic forced after error\n",
694 			sb->s_id);
695 	}
696 
697 	if (sb_rdonly(sb) || continue_fs)
698 		return;
699 
700 	ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
701 	/*
702 	 * Make sure updated value of ->s_mount_flags will be visible before
703 	 * ->s_flags update
704 	 */
705 	smp_wmb();
706 	sb->s_flags |= SB_RDONLY;
707 }
708 
709 static void flush_stashed_error_work(struct work_struct *work)
710 {
711 	struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
712 						s_error_work);
713 	journal_t *journal = sbi->s_journal;
714 	handle_t *handle;
715 
716 	/*
717 	 * If the journal is still running, we have to write out superblock
718 	 * through the journal to avoid collisions of other journalled sb
719 	 * updates.
720 	 *
721 	 * We use directly jbd2 functions here to avoid recursing back into
722 	 * ext4 error handling code during handling of previous errors.
723 	 */
724 	if (!sb_rdonly(sbi->s_sb) && journal) {
725 		struct buffer_head *sbh = sbi->s_sbh;
726 		handle = jbd2_journal_start(journal, 1);
727 		if (IS_ERR(handle))
728 			goto write_directly;
729 		if (jbd2_journal_get_write_access(handle, sbh)) {
730 			jbd2_journal_stop(handle);
731 			goto write_directly;
732 		}
733 		ext4_update_super(sbi->s_sb);
734 		if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
735 			ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
736 				 "superblock detected");
737 			clear_buffer_write_io_error(sbh);
738 			set_buffer_uptodate(sbh);
739 		}
740 
741 		if (jbd2_journal_dirty_metadata(handle, sbh)) {
742 			jbd2_journal_stop(handle);
743 			goto write_directly;
744 		}
745 		jbd2_journal_stop(handle);
746 		ext4_notify_error_sysfs(sbi);
747 		return;
748 	}
749 write_directly:
750 	/*
751 	 * Write through journal failed. Write sb directly to get error info
752 	 * out and hope for the best.
753 	 */
754 	ext4_commit_super(sbi->s_sb);
755 	ext4_notify_error_sysfs(sbi);
756 }
757 
758 #define ext4_error_ratelimit(sb)					\
759 		___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),	\
760 			     "EXT4-fs error")
761 
762 void __ext4_error(struct super_block *sb, const char *function,
763 		  unsigned int line, bool force_ro, int error, __u64 block,
764 		  const char *fmt, ...)
765 {
766 	struct va_format vaf;
767 	va_list args;
768 
769 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
770 		return;
771 
772 	trace_ext4_error(sb, function, line);
773 	if (ext4_error_ratelimit(sb)) {
774 		va_start(args, fmt);
775 		vaf.fmt = fmt;
776 		vaf.va = &args;
777 		printk(KERN_CRIT
778 		       "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
779 		       sb->s_id, function, line, current->comm, &vaf);
780 		va_end(args);
781 	}
782 	fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
783 
784 	ext4_handle_error(sb, force_ro, error, 0, block, function, line);
785 }
786 
787 void __ext4_error_inode(struct inode *inode, const char *function,
788 			unsigned int line, ext4_fsblk_t block, int error,
789 			const char *fmt, ...)
790 {
791 	va_list args;
792 	struct va_format vaf;
793 
794 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
795 		return;
796 
797 	trace_ext4_error(inode->i_sb, function, line);
798 	if (ext4_error_ratelimit(inode->i_sb)) {
799 		va_start(args, fmt);
800 		vaf.fmt = fmt;
801 		vaf.va = &args;
802 		if (block)
803 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
804 			       "inode #%lu: block %llu: comm %s: %pV\n",
805 			       inode->i_sb->s_id, function, line, inode->i_ino,
806 			       block, current->comm, &vaf);
807 		else
808 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
809 			       "inode #%lu: comm %s: %pV\n",
810 			       inode->i_sb->s_id, function, line, inode->i_ino,
811 			       current->comm, &vaf);
812 		va_end(args);
813 	}
814 	fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
815 
816 	ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
817 			  function, line);
818 }
819 
820 void __ext4_error_file(struct file *file, const char *function,
821 		       unsigned int line, ext4_fsblk_t block,
822 		       const char *fmt, ...)
823 {
824 	va_list args;
825 	struct va_format vaf;
826 	struct inode *inode = file_inode(file);
827 	char pathname[80], *path;
828 
829 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
830 		return;
831 
832 	trace_ext4_error(inode->i_sb, function, line);
833 	if (ext4_error_ratelimit(inode->i_sb)) {
834 		path = file_path(file, pathname, sizeof(pathname));
835 		if (IS_ERR(path))
836 			path = "(unknown)";
837 		va_start(args, fmt);
838 		vaf.fmt = fmt;
839 		vaf.va = &args;
840 		if (block)
841 			printk(KERN_CRIT
842 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
843 			       "block %llu: comm %s: path %s: %pV\n",
844 			       inode->i_sb->s_id, function, line, inode->i_ino,
845 			       block, current->comm, path, &vaf);
846 		else
847 			printk(KERN_CRIT
848 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
849 			       "comm %s: path %s: %pV\n",
850 			       inode->i_sb->s_id, function, line, inode->i_ino,
851 			       current->comm, path, &vaf);
852 		va_end(args);
853 	}
854 	fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
855 
856 	ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
857 			  function, line);
858 }
859 
860 const char *ext4_decode_error(struct super_block *sb, int errno,
861 			      char nbuf[16])
862 {
863 	char *errstr = NULL;
864 
865 	switch (errno) {
866 	case -EFSCORRUPTED:
867 		errstr = "Corrupt filesystem";
868 		break;
869 	case -EFSBADCRC:
870 		errstr = "Filesystem failed CRC";
871 		break;
872 	case -EIO:
873 		errstr = "IO failure";
874 		break;
875 	case -ENOMEM:
876 		errstr = "Out of memory";
877 		break;
878 	case -EROFS:
879 		if (!sb || (EXT4_SB(sb)->s_journal &&
880 			    EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
881 			errstr = "Journal has aborted";
882 		else
883 			errstr = "Readonly filesystem";
884 		break;
885 	default:
886 		/* If the caller passed in an extra buffer for unknown
887 		 * errors, textualise them now.  Else we just return
888 		 * NULL. */
889 		if (nbuf) {
890 			/* Check for truncated error codes... */
891 			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
892 				errstr = nbuf;
893 		}
894 		break;
895 	}
896 
897 	return errstr;
898 }
899 
900 /* __ext4_std_error decodes expected errors from journaling functions
901  * automatically and invokes the appropriate error response.  */
902 
903 void __ext4_std_error(struct super_block *sb, const char *function,
904 		      unsigned int line, int errno)
905 {
906 	char nbuf[16];
907 	const char *errstr;
908 
909 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
910 		return;
911 
912 	/* Special case: if the error is EROFS, and we're not already
913 	 * inside a transaction, then there's really no point in logging
914 	 * an error. */
915 	if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
916 		return;
917 
918 	if (ext4_error_ratelimit(sb)) {
919 		errstr = ext4_decode_error(sb, errno, nbuf);
920 		printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
921 		       sb->s_id, function, line, errstr);
922 	}
923 	fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
924 
925 	ext4_handle_error(sb, false, -errno, 0, 0, function, line);
926 }
927 
928 void __ext4_msg(struct super_block *sb,
929 		const char *prefix, const char *fmt, ...)
930 {
931 	struct va_format vaf;
932 	va_list args;
933 
934 	if (sb) {
935 		atomic_inc(&EXT4_SB(sb)->s_msg_count);
936 		if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
937 				  "EXT4-fs"))
938 			return;
939 	}
940 
941 	va_start(args, fmt);
942 	vaf.fmt = fmt;
943 	vaf.va = &args;
944 	if (sb)
945 		printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
946 	else
947 		printk("%sEXT4-fs: %pV\n", prefix, &vaf);
948 	va_end(args);
949 }
950 
951 static int ext4_warning_ratelimit(struct super_block *sb)
952 {
953 	atomic_inc(&EXT4_SB(sb)->s_warning_count);
954 	return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
955 			    "EXT4-fs warning");
956 }
957 
958 void __ext4_warning(struct super_block *sb, const char *function,
959 		    unsigned int line, const char *fmt, ...)
960 {
961 	struct va_format vaf;
962 	va_list args;
963 
964 	if (!ext4_warning_ratelimit(sb))
965 		return;
966 
967 	va_start(args, fmt);
968 	vaf.fmt = fmt;
969 	vaf.va = &args;
970 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
971 	       sb->s_id, function, line, &vaf);
972 	va_end(args);
973 }
974 
975 void __ext4_warning_inode(const struct inode *inode, const char *function,
976 			  unsigned int line, const char *fmt, ...)
977 {
978 	struct va_format vaf;
979 	va_list args;
980 
981 	if (!ext4_warning_ratelimit(inode->i_sb))
982 		return;
983 
984 	va_start(args, fmt);
985 	vaf.fmt = fmt;
986 	vaf.va = &args;
987 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
988 	       "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
989 	       function, line, inode->i_ino, current->comm, &vaf);
990 	va_end(args);
991 }
992 
993 void __ext4_grp_locked_error(const char *function, unsigned int line,
994 			     struct super_block *sb, ext4_group_t grp,
995 			     unsigned long ino, ext4_fsblk_t block,
996 			     const char *fmt, ...)
997 __releases(bitlock)
998 __acquires(bitlock)
999 {
1000 	struct va_format vaf;
1001 	va_list args;
1002 
1003 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
1004 		return;
1005 
1006 	trace_ext4_error(sb, function, line);
1007 	if (ext4_error_ratelimit(sb)) {
1008 		va_start(args, fmt);
1009 		vaf.fmt = fmt;
1010 		vaf.va = &args;
1011 		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1012 		       sb->s_id, function, line, grp);
1013 		if (ino)
1014 			printk(KERN_CONT "inode %lu: ", ino);
1015 		if (block)
1016 			printk(KERN_CONT "block %llu:",
1017 			       (unsigned long long) block);
1018 		printk(KERN_CONT "%pV\n", &vaf);
1019 		va_end(args);
1020 	}
1021 
1022 	if (test_opt(sb, ERRORS_CONT)) {
1023 		if (test_opt(sb, WARN_ON_ERROR))
1024 			WARN_ON_ONCE(1);
1025 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1026 		if (!bdev_read_only(sb->s_bdev)) {
1027 			save_error_info(sb, EFSCORRUPTED, ino, block, function,
1028 					line);
1029 			schedule_work(&EXT4_SB(sb)->s_error_work);
1030 		}
1031 		return;
1032 	}
1033 	ext4_unlock_group(sb, grp);
1034 	ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1035 	/*
1036 	 * We only get here in the ERRORS_RO case; relocking the group
1037 	 * may be dangerous, but nothing bad will happen since the
1038 	 * filesystem will have already been marked read/only and the
1039 	 * journal has been aborted.  We return 1 as a hint to callers
1040 	 * who might what to use the return value from
1041 	 * ext4_grp_locked_error() to distinguish between the
1042 	 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1043 	 * aggressively from the ext4 function in question, with a
1044 	 * more appropriate error code.
1045 	 */
1046 	ext4_lock_group(sb, grp);
1047 	return;
1048 }
1049 
1050 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1051 				     ext4_group_t group,
1052 				     unsigned int flags)
1053 {
1054 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1055 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1056 	struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1057 	int ret;
1058 
1059 	if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1060 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1061 					    &grp->bb_state);
1062 		if (!ret)
1063 			percpu_counter_sub(&sbi->s_freeclusters_counter,
1064 					   grp->bb_free);
1065 	}
1066 
1067 	if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1068 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1069 					    &grp->bb_state);
1070 		if (!ret && gdp) {
1071 			int count;
1072 
1073 			count = ext4_free_inodes_count(sb, gdp);
1074 			percpu_counter_sub(&sbi->s_freeinodes_counter,
1075 					   count);
1076 		}
1077 	}
1078 }
1079 
1080 void ext4_update_dynamic_rev(struct super_block *sb)
1081 {
1082 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1083 
1084 	if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1085 		return;
1086 
1087 	ext4_warning(sb,
1088 		     "updating to rev %d because of new feature flag, "
1089 		     "running e2fsck is recommended",
1090 		     EXT4_DYNAMIC_REV);
1091 
1092 	es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1093 	es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1094 	es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1095 	/* leave es->s_feature_*compat flags alone */
1096 	/* es->s_uuid will be set by e2fsck if empty */
1097 
1098 	/*
1099 	 * The rest of the superblock fields should be zero, and if not it
1100 	 * means they are likely already in use, so leave them alone.  We
1101 	 * can leave it up to e2fsck to clean up any inconsistencies there.
1102 	 */
1103 }
1104 
1105 /*
1106  * Open the external journal device
1107  */
1108 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1109 {
1110 	struct block_device *bdev;
1111 
1112 	bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1113 	if (IS_ERR(bdev))
1114 		goto fail;
1115 	return bdev;
1116 
1117 fail:
1118 	ext4_msg(sb, KERN_ERR,
1119 		 "failed to open journal device unknown-block(%u,%u) %ld",
1120 		 MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1121 	return NULL;
1122 }
1123 
1124 /*
1125  * Release the journal device
1126  */
1127 static void ext4_blkdev_put(struct block_device *bdev)
1128 {
1129 	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1130 }
1131 
1132 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1133 {
1134 	struct block_device *bdev;
1135 	bdev = sbi->s_journal_bdev;
1136 	if (bdev) {
1137 		ext4_blkdev_put(bdev);
1138 		sbi->s_journal_bdev = NULL;
1139 	}
1140 }
1141 
1142 static inline struct inode *orphan_list_entry(struct list_head *l)
1143 {
1144 	return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1145 }
1146 
1147 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1148 {
1149 	struct list_head *l;
1150 
1151 	ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1152 		 le32_to_cpu(sbi->s_es->s_last_orphan));
1153 
1154 	printk(KERN_ERR "sb_info orphan list:\n");
1155 	list_for_each(l, &sbi->s_orphan) {
1156 		struct inode *inode = orphan_list_entry(l);
1157 		printk(KERN_ERR "  "
1158 		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1159 		       inode->i_sb->s_id, inode->i_ino, inode,
1160 		       inode->i_mode, inode->i_nlink,
1161 		       NEXT_ORPHAN(inode));
1162 	}
1163 }
1164 
1165 #ifdef CONFIG_QUOTA
1166 static int ext4_quota_off(struct super_block *sb, int type);
1167 
1168 static inline void ext4_quota_off_umount(struct super_block *sb)
1169 {
1170 	int type;
1171 
1172 	/* Use our quota_off function to clear inode flags etc. */
1173 	for (type = 0; type < EXT4_MAXQUOTAS; type++)
1174 		ext4_quota_off(sb, type);
1175 }
1176 
1177 /*
1178  * This is a helper function which is used in the mount/remount
1179  * codepaths (which holds s_umount) to fetch the quota file name.
1180  */
1181 static inline char *get_qf_name(struct super_block *sb,
1182 				struct ext4_sb_info *sbi,
1183 				int type)
1184 {
1185 	return rcu_dereference_protected(sbi->s_qf_names[type],
1186 					 lockdep_is_held(&sb->s_umount));
1187 }
1188 #else
1189 static inline void ext4_quota_off_umount(struct super_block *sb)
1190 {
1191 }
1192 #endif
1193 
1194 static void ext4_put_super(struct super_block *sb)
1195 {
1196 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1197 	struct ext4_super_block *es = sbi->s_es;
1198 	struct buffer_head **group_desc;
1199 	struct flex_groups **flex_groups;
1200 	int aborted = 0;
1201 	int i, err;
1202 
1203 	ext4_unregister_li_request(sb);
1204 	ext4_quota_off_umount(sb);
1205 
1206 	flush_work(&sbi->s_error_work);
1207 	destroy_workqueue(sbi->rsv_conversion_wq);
1208 	ext4_release_orphan_info(sb);
1209 
1210 	/*
1211 	 * Unregister sysfs before destroying jbd2 journal.
1212 	 * Since we could still access attr_journal_task attribute via sysfs
1213 	 * path which could have sbi->s_journal->j_task as NULL
1214 	 */
1215 	ext4_unregister_sysfs(sb);
1216 
1217 	if (sbi->s_journal) {
1218 		aborted = is_journal_aborted(sbi->s_journal);
1219 		err = jbd2_journal_destroy(sbi->s_journal);
1220 		sbi->s_journal = NULL;
1221 		if ((err < 0) && !aborted) {
1222 			ext4_abort(sb, -err, "Couldn't clean up the journal");
1223 		}
1224 	}
1225 
1226 	ext4_es_unregister_shrinker(sbi);
1227 	del_timer_sync(&sbi->s_err_report);
1228 	ext4_release_system_zone(sb);
1229 	ext4_mb_release(sb);
1230 	ext4_ext_release(sb);
1231 
1232 	if (!sb_rdonly(sb) && !aborted) {
1233 		ext4_clear_feature_journal_needs_recovery(sb);
1234 		ext4_clear_feature_orphan_present(sb);
1235 		es->s_state = cpu_to_le16(sbi->s_mount_state);
1236 	}
1237 	if (!sb_rdonly(sb))
1238 		ext4_commit_super(sb);
1239 
1240 	rcu_read_lock();
1241 	group_desc = rcu_dereference(sbi->s_group_desc);
1242 	for (i = 0; i < sbi->s_gdb_count; i++)
1243 		brelse(group_desc[i]);
1244 	kvfree(group_desc);
1245 	flex_groups = rcu_dereference(sbi->s_flex_groups);
1246 	if (flex_groups) {
1247 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1248 			kvfree(flex_groups[i]);
1249 		kvfree(flex_groups);
1250 	}
1251 	rcu_read_unlock();
1252 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
1253 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
1254 	percpu_counter_destroy(&sbi->s_dirs_counter);
1255 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1256 	percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1257 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
1258 #ifdef CONFIG_QUOTA
1259 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
1260 		kfree(get_qf_name(sb, sbi, i));
1261 #endif
1262 
1263 	/* Debugging code just in case the in-memory inode orphan list
1264 	 * isn't empty.  The on-disk one can be non-empty if we've
1265 	 * detected an error and taken the fs readonly, but the
1266 	 * in-memory list had better be clean by this point. */
1267 	if (!list_empty(&sbi->s_orphan))
1268 		dump_orphan_list(sb, sbi);
1269 	ASSERT(list_empty(&sbi->s_orphan));
1270 
1271 	sync_blockdev(sb->s_bdev);
1272 	invalidate_bdev(sb->s_bdev);
1273 	if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1274 		/*
1275 		 * Invalidate the journal device's buffers.  We don't want them
1276 		 * floating about in memory - the physical journal device may
1277 		 * hotswapped, and it breaks the `ro-after' testing code.
1278 		 */
1279 		sync_blockdev(sbi->s_journal_bdev);
1280 		invalidate_bdev(sbi->s_journal_bdev);
1281 		ext4_blkdev_remove(sbi);
1282 	}
1283 
1284 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1285 	sbi->s_ea_inode_cache = NULL;
1286 
1287 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1288 	sbi->s_ea_block_cache = NULL;
1289 
1290 	ext4_stop_mmpd(sbi);
1291 
1292 	brelse(sbi->s_sbh);
1293 	sb->s_fs_info = NULL;
1294 	/*
1295 	 * Now that we are completely done shutting down the
1296 	 * superblock, we need to actually destroy the kobject.
1297 	 */
1298 	kobject_put(&sbi->s_kobj);
1299 	wait_for_completion(&sbi->s_kobj_unregister);
1300 	if (sbi->s_chksum_driver)
1301 		crypto_free_shash(sbi->s_chksum_driver);
1302 	kfree(sbi->s_blockgroup_lock);
1303 	fs_put_dax(sbi->s_daxdev);
1304 	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1305 #ifdef CONFIG_UNICODE
1306 	utf8_unload(sb->s_encoding);
1307 #endif
1308 	kfree(sbi);
1309 }
1310 
1311 static struct kmem_cache *ext4_inode_cachep;
1312 
1313 /*
1314  * Called inside transaction, so use GFP_NOFS
1315  */
1316 static struct inode *ext4_alloc_inode(struct super_block *sb)
1317 {
1318 	struct ext4_inode_info *ei;
1319 
1320 	ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1321 	if (!ei)
1322 		return NULL;
1323 
1324 	inode_set_iversion(&ei->vfs_inode, 1);
1325 	spin_lock_init(&ei->i_raw_lock);
1326 	INIT_LIST_HEAD(&ei->i_prealloc_list);
1327 	atomic_set(&ei->i_prealloc_active, 0);
1328 	spin_lock_init(&ei->i_prealloc_lock);
1329 	ext4_es_init_tree(&ei->i_es_tree);
1330 	rwlock_init(&ei->i_es_lock);
1331 	INIT_LIST_HEAD(&ei->i_es_list);
1332 	ei->i_es_all_nr = 0;
1333 	ei->i_es_shk_nr = 0;
1334 	ei->i_es_shrink_lblk = 0;
1335 	ei->i_reserved_data_blocks = 0;
1336 	spin_lock_init(&(ei->i_block_reservation_lock));
1337 	ext4_init_pending_tree(&ei->i_pending_tree);
1338 #ifdef CONFIG_QUOTA
1339 	ei->i_reserved_quota = 0;
1340 	memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1341 #endif
1342 	ei->jinode = NULL;
1343 	INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1344 	spin_lock_init(&ei->i_completed_io_lock);
1345 	ei->i_sync_tid = 0;
1346 	ei->i_datasync_tid = 0;
1347 	atomic_set(&ei->i_unwritten, 0);
1348 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1349 	ext4_fc_init_inode(&ei->vfs_inode);
1350 	mutex_init(&ei->i_fc_lock);
1351 	return &ei->vfs_inode;
1352 }
1353 
1354 static int ext4_drop_inode(struct inode *inode)
1355 {
1356 	int drop = generic_drop_inode(inode);
1357 
1358 	if (!drop)
1359 		drop = fscrypt_drop_inode(inode);
1360 
1361 	trace_ext4_drop_inode(inode, drop);
1362 	return drop;
1363 }
1364 
1365 static void ext4_free_in_core_inode(struct inode *inode)
1366 {
1367 	fscrypt_free_inode(inode);
1368 	if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1369 		pr_warn("%s: inode %ld still in fc list",
1370 			__func__, inode->i_ino);
1371 	}
1372 	kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1373 }
1374 
1375 static void ext4_destroy_inode(struct inode *inode)
1376 {
1377 	if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1378 		ext4_msg(inode->i_sb, KERN_ERR,
1379 			 "Inode %lu (%p): orphan list check failed!",
1380 			 inode->i_ino, EXT4_I(inode));
1381 		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1382 				EXT4_I(inode), sizeof(struct ext4_inode_info),
1383 				true);
1384 		dump_stack();
1385 	}
1386 
1387 	if (EXT4_I(inode)->i_reserved_data_blocks)
1388 		ext4_msg(inode->i_sb, KERN_ERR,
1389 			 "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1390 			 inode->i_ino, EXT4_I(inode),
1391 			 EXT4_I(inode)->i_reserved_data_blocks);
1392 }
1393 
1394 static void init_once(void *foo)
1395 {
1396 	struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1397 
1398 	INIT_LIST_HEAD(&ei->i_orphan);
1399 	init_rwsem(&ei->xattr_sem);
1400 	init_rwsem(&ei->i_data_sem);
1401 	inode_init_once(&ei->vfs_inode);
1402 	ext4_fc_init_inode(&ei->vfs_inode);
1403 }
1404 
1405 static int __init init_inodecache(void)
1406 {
1407 	ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1408 				sizeof(struct ext4_inode_info), 0,
1409 				(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1410 					SLAB_ACCOUNT),
1411 				offsetof(struct ext4_inode_info, i_data),
1412 				sizeof_field(struct ext4_inode_info, i_data),
1413 				init_once);
1414 	if (ext4_inode_cachep == NULL)
1415 		return -ENOMEM;
1416 	return 0;
1417 }
1418 
1419 static void destroy_inodecache(void)
1420 {
1421 	/*
1422 	 * Make sure all delayed rcu free inodes are flushed before we
1423 	 * destroy cache.
1424 	 */
1425 	rcu_barrier();
1426 	kmem_cache_destroy(ext4_inode_cachep);
1427 }
1428 
1429 void ext4_clear_inode(struct inode *inode)
1430 {
1431 	ext4_fc_del(inode);
1432 	invalidate_inode_buffers(inode);
1433 	clear_inode(inode);
1434 	ext4_discard_preallocations(inode, 0);
1435 	ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1436 	dquot_drop(inode);
1437 	if (EXT4_I(inode)->jinode) {
1438 		jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1439 					       EXT4_I(inode)->jinode);
1440 		jbd2_free_inode(EXT4_I(inode)->jinode);
1441 		EXT4_I(inode)->jinode = NULL;
1442 	}
1443 	fscrypt_put_encryption_info(inode);
1444 	fsverity_cleanup_inode(inode);
1445 }
1446 
1447 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1448 					u64 ino, u32 generation)
1449 {
1450 	struct inode *inode;
1451 
1452 	/*
1453 	 * Currently we don't know the generation for parent directory, so
1454 	 * a generation of 0 means "accept any"
1455 	 */
1456 	inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1457 	if (IS_ERR(inode))
1458 		return ERR_CAST(inode);
1459 	if (generation && inode->i_generation != generation) {
1460 		iput(inode);
1461 		return ERR_PTR(-ESTALE);
1462 	}
1463 
1464 	return inode;
1465 }
1466 
1467 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1468 					int fh_len, int fh_type)
1469 {
1470 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1471 				    ext4_nfs_get_inode);
1472 }
1473 
1474 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1475 					int fh_len, int fh_type)
1476 {
1477 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1478 				    ext4_nfs_get_inode);
1479 }
1480 
1481 static int ext4_nfs_commit_metadata(struct inode *inode)
1482 {
1483 	struct writeback_control wbc = {
1484 		.sync_mode = WB_SYNC_ALL
1485 	};
1486 
1487 	trace_ext4_nfs_commit_metadata(inode);
1488 	return ext4_write_inode(inode, &wbc);
1489 }
1490 
1491 #ifdef CONFIG_FS_ENCRYPTION
1492 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1493 {
1494 	return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1495 				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1496 }
1497 
1498 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1499 							void *fs_data)
1500 {
1501 	handle_t *handle = fs_data;
1502 	int res, res2, credits, retries = 0;
1503 
1504 	/*
1505 	 * Encrypting the root directory is not allowed because e2fsck expects
1506 	 * lost+found to exist and be unencrypted, and encrypting the root
1507 	 * directory would imply encrypting the lost+found directory as well as
1508 	 * the filename "lost+found" itself.
1509 	 */
1510 	if (inode->i_ino == EXT4_ROOT_INO)
1511 		return -EPERM;
1512 
1513 	if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1514 		return -EINVAL;
1515 
1516 	if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1517 		return -EOPNOTSUPP;
1518 
1519 	res = ext4_convert_inline_data(inode);
1520 	if (res)
1521 		return res;
1522 
1523 	/*
1524 	 * If a journal handle was specified, then the encryption context is
1525 	 * being set on a new inode via inheritance and is part of a larger
1526 	 * transaction to create the inode.  Otherwise the encryption context is
1527 	 * being set on an existing inode in its own transaction.  Only in the
1528 	 * latter case should the "retry on ENOSPC" logic be used.
1529 	 */
1530 
1531 	if (handle) {
1532 		res = ext4_xattr_set_handle(handle, inode,
1533 					    EXT4_XATTR_INDEX_ENCRYPTION,
1534 					    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1535 					    ctx, len, 0);
1536 		if (!res) {
1537 			ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1538 			ext4_clear_inode_state(inode,
1539 					EXT4_STATE_MAY_INLINE_DATA);
1540 			/*
1541 			 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1542 			 * S_DAX may be disabled
1543 			 */
1544 			ext4_set_inode_flags(inode, false);
1545 		}
1546 		return res;
1547 	}
1548 
1549 	res = dquot_initialize(inode);
1550 	if (res)
1551 		return res;
1552 retry:
1553 	res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1554 				     &credits);
1555 	if (res)
1556 		return res;
1557 
1558 	handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1559 	if (IS_ERR(handle))
1560 		return PTR_ERR(handle);
1561 
1562 	res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1563 				    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1564 				    ctx, len, 0);
1565 	if (!res) {
1566 		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1567 		/*
1568 		 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1569 		 * S_DAX may be disabled
1570 		 */
1571 		ext4_set_inode_flags(inode, false);
1572 		res = ext4_mark_inode_dirty(handle, inode);
1573 		if (res)
1574 			EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1575 	}
1576 	res2 = ext4_journal_stop(handle);
1577 
1578 	if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1579 		goto retry;
1580 	if (!res)
1581 		res = res2;
1582 	return res;
1583 }
1584 
1585 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1586 {
1587 	return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1588 }
1589 
1590 static bool ext4_has_stable_inodes(struct super_block *sb)
1591 {
1592 	return ext4_has_feature_stable_inodes(sb);
1593 }
1594 
1595 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1596 				       int *ino_bits_ret, int *lblk_bits_ret)
1597 {
1598 	*ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1599 	*lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1600 }
1601 
1602 static const struct fscrypt_operations ext4_cryptops = {
1603 	.key_prefix		= "ext4:",
1604 	.get_context		= ext4_get_context,
1605 	.set_context		= ext4_set_context,
1606 	.get_dummy_policy	= ext4_get_dummy_policy,
1607 	.empty_dir		= ext4_empty_dir,
1608 	.has_stable_inodes	= ext4_has_stable_inodes,
1609 	.get_ino_and_lblk_bits	= ext4_get_ino_and_lblk_bits,
1610 };
1611 #endif
1612 
1613 #ifdef CONFIG_QUOTA
1614 static const char * const quotatypes[] = INITQFNAMES;
1615 #define QTYPE2NAME(t) (quotatypes[t])
1616 
1617 static int ext4_write_dquot(struct dquot *dquot);
1618 static int ext4_acquire_dquot(struct dquot *dquot);
1619 static int ext4_release_dquot(struct dquot *dquot);
1620 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1621 static int ext4_write_info(struct super_block *sb, int type);
1622 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1623 			 const struct path *path);
1624 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1625 			       size_t len, loff_t off);
1626 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1627 				const char *data, size_t len, loff_t off);
1628 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1629 			     unsigned int flags);
1630 
1631 static struct dquot **ext4_get_dquots(struct inode *inode)
1632 {
1633 	return EXT4_I(inode)->i_dquot;
1634 }
1635 
1636 static const struct dquot_operations ext4_quota_operations = {
1637 	.get_reserved_space	= ext4_get_reserved_space,
1638 	.write_dquot		= ext4_write_dquot,
1639 	.acquire_dquot		= ext4_acquire_dquot,
1640 	.release_dquot		= ext4_release_dquot,
1641 	.mark_dirty		= ext4_mark_dquot_dirty,
1642 	.write_info		= ext4_write_info,
1643 	.alloc_dquot		= dquot_alloc,
1644 	.destroy_dquot		= dquot_destroy,
1645 	.get_projid		= ext4_get_projid,
1646 	.get_inode_usage	= ext4_get_inode_usage,
1647 	.get_next_id		= dquot_get_next_id,
1648 };
1649 
1650 static const struct quotactl_ops ext4_qctl_operations = {
1651 	.quota_on	= ext4_quota_on,
1652 	.quota_off	= ext4_quota_off,
1653 	.quota_sync	= dquot_quota_sync,
1654 	.get_state	= dquot_get_state,
1655 	.set_info	= dquot_set_dqinfo,
1656 	.get_dqblk	= dquot_get_dqblk,
1657 	.set_dqblk	= dquot_set_dqblk,
1658 	.get_nextdqblk	= dquot_get_next_dqblk,
1659 };
1660 #endif
1661 
1662 static const struct super_operations ext4_sops = {
1663 	.alloc_inode	= ext4_alloc_inode,
1664 	.free_inode	= ext4_free_in_core_inode,
1665 	.destroy_inode	= ext4_destroy_inode,
1666 	.write_inode	= ext4_write_inode,
1667 	.dirty_inode	= ext4_dirty_inode,
1668 	.drop_inode	= ext4_drop_inode,
1669 	.evict_inode	= ext4_evict_inode,
1670 	.put_super	= ext4_put_super,
1671 	.sync_fs	= ext4_sync_fs,
1672 	.freeze_fs	= ext4_freeze,
1673 	.unfreeze_fs	= ext4_unfreeze,
1674 	.statfs		= ext4_statfs,
1675 	.show_options	= ext4_show_options,
1676 #ifdef CONFIG_QUOTA
1677 	.quota_read	= ext4_quota_read,
1678 	.quota_write	= ext4_quota_write,
1679 	.get_dquots	= ext4_get_dquots,
1680 #endif
1681 };
1682 
1683 static const struct export_operations ext4_export_ops = {
1684 	.fh_to_dentry = ext4_fh_to_dentry,
1685 	.fh_to_parent = ext4_fh_to_parent,
1686 	.get_parent = ext4_get_parent,
1687 	.commit_metadata = ext4_nfs_commit_metadata,
1688 };
1689 
1690 enum {
1691 	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1692 	Opt_resgid, Opt_resuid, Opt_sb,
1693 	Opt_nouid32, Opt_debug, Opt_removed,
1694 	Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1695 	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1696 	Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1697 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1698 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1699 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1700 	Opt_inlinecrypt,
1701 	Opt_usrjquota, Opt_grpjquota, Opt_quota,
1702 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1703 	Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1704 	Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1705 	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1706 	Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1707 	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1708 	Opt_inode_readahead_blks, Opt_journal_ioprio,
1709 	Opt_dioread_nolock, Opt_dioread_lock,
1710 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1711 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1712 	Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1713 	Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1714 #ifdef CONFIG_EXT4_DEBUG
1715 	Opt_fc_debug_max_replay, Opt_fc_debug_force
1716 #endif
1717 };
1718 
1719 static const struct constant_table ext4_param_errors[] = {
1720 	{"continue",	EXT4_MOUNT_ERRORS_CONT},
1721 	{"panic",	EXT4_MOUNT_ERRORS_PANIC},
1722 	{"remount-ro",	EXT4_MOUNT_ERRORS_RO},
1723 	{}
1724 };
1725 
1726 static const struct constant_table ext4_param_data[] = {
1727 	{"journal",	EXT4_MOUNT_JOURNAL_DATA},
1728 	{"ordered",	EXT4_MOUNT_ORDERED_DATA},
1729 	{"writeback",	EXT4_MOUNT_WRITEBACK_DATA},
1730 	{}
1731 };
1732 
1733 static const struct constant_table ext4_param_data_err[] = {
1734 	{"abort",	Opt_data_err_abort},
1735 	{"ignore",	Opt_data_err_ignore},
1736 	{}
1737 };
1738 
1739 static const struct constant_table ext4_param_jqfmt[] = {
1740 	{"vfsold",	QFMT_VFS_OLD},
1741 	{"vfsv0",	QFMT_VFS_V0},
1742 	{"vfsv1",	QFMT_VFS_V1},
1743 	{}
1744 };
1745 
1746 static const struct constant_table ext4_param_dax[] = {
1747 	{"always",	Opt_dax_always},
1748 	{"inode",	Opt_dax_inode},
1749 	{"never",	Opt_dax_never},
1750 	{}
1751 };
1752 
1753 /* String parameter that allows empty argument */
1754 #define fsparam_string_empty(NAME, OPT) \
1755 	__fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1756 
1757 /*
1758  * Mount option specification
1759  * We don't use fsparam_flag_no because of the way we set the
1760  * options and the way we show them in _ext4_show_options(). To
1761  * keep the changes to a minimum, let's keep the negative options
1762  * separate for now.
1763  */
1764 static const struct fs_parameter_spec ext4_param_specs[] = {
1765 	fsparam_flag	("bsddf",		Opt_bsd_df),
1766 	fsparam_flag	("minixdf",		Opt_minix_df),
1767 	fsparam_flag	("grpid",		Opt_grpid),
1768 	fsparam_flag	("bsdgroups",		Opt_grpid),
1769 	fsparam_flag	("nogrpid",		Opt_nogrpid),
1770 	fsparam_flag	("sysvgroups",		Opt_nogrpid),
1771 	fsparam_u32	("resgid",		Opt_resgid),
1772 	fsparam_u32	("resuid",		Opt_resuid),
1773 	fsparam_u32	("sb",			Opt_sb),
1774 	fsparam_enum	("errors",		Opt_errors, ext4_param_errors),
1775 	fsparam_flag	("nouid32",		Opt_nouid32),
1776 	fsparam_flag	("debug",		Opt_debug),
1777 	fsparam_flag	("oldalloc",		Opt_removed),
1778 	fsparam_flag	("orlov",		Opt_removed),
1779 	fsparam_flag	("user_xattr",		Opt_user_xattr),
1780 	fsparam_flag	("nouser_xattr",	Opt_nouser_xattr),
1781 	fsparam_flag	("acl",			Opt_acl),
1782 	fsparam_flag	("noacl",		Opt_noacl),
1783 	fsparam_flag	("norecovery",		Opt_noload),
1784 	fsparam_flag	("noload",		Opt_noload),
1785 	fsparam_flag	("bh",			Opt_removed),
1786 	fsparam_flag	("nobh",		Opt_removed),
1787 	fsparam_u32	("commit",		Opt_commit),
1788 	fsparam_u32	("min_batch_time",	Opt_min_batch_time),
1789 	fsparam_u32	("max_batch_time",	Opt_max_batch_time),
1790 	fsparam_u32	("journal_dev",		Opt_journal_dev),
1791 	fsparam_bdev	("journal_path",	Opt_journal_path),
1792 	fsparam_flag	("journal_checksum",	Opt_journal_checksum),
1793 	fsparam_flag	("nojournal_checksum",	Opt_nojournal_checksum),
1794 	fsparam_flag	("journal_async_commit",Opt_journal_async_commit),
1795 	fsparam_flag	("abort",		Opt_abort),
1796 	fsparam_enum	("data",		Opt_data, ext4_param_data),
1797 	fsparam_enum	("data_err",		Opt_data_err,
1798 						ext4_param_data_err),
1799 	fsparam_string_empty
1800 			("usrjquota",		Opt_usrjquota),
1801 	fsparam_string_empty
1802 			("grpjquota",		Opt_grpjquota),
1803 	fsparam_enum	("jqfmt",		Opt_jqfmt, ext4_param_jqfmt),
1804 	fsparam_flag	("grpquota",		Opt_grpquota),
1805 	fsparam_flag	("quota",		Opt_quota),
1806 	fsparam_flag	("noquota",		Opt_noquota),
1807 	fsparam_flag	("usrquota",		Opt_usrquota),
1808 	fsparam_flag	("prjquota",		Opt_prjquota),
1809 	fsparam_flag	("barrier",		Opt_barrier),
1810 	fsparam_u32	("barrier",		Opt_barrier),
1811 	fsparam_flag	("nobarrier",		Opt_nobarrier),
1812 	fsparam_flag	("i_version",		Opt_i_version),
1813 	fsparam_flag	("dax",			Opt_dax),
1814 	fsparam_enum	("dax",			Opt_dax_type, ext4_param_dax),
1815 	fsparam_u32	("stripe",		Opt_stripe),
1816 	fsparam_flag	("delalloc",		Opt_delalloc),
1817 	fsparam_flag	("nodelalloc",		Opt_nodelalloc),
1818 	fsparam_flag	("warn_on_error",	Opt_warn_on_error),
1819 	fsparam_flag	("nowarn_on_error",	Opt_nowarn_on_error),
1820 	fsparam_u32	("debug_want_extra_isize",
1821 						Opt_debug_want_extra_isize),
1822 	fsparam_flag	("mblk_io_submit",	Opt_removed),
1823 	fsparam_flag	("nomblk_io_submit",	Opt_removed),
1824 	fsparam_flag	("block_validity",	Opt_block_validity),
1825 	fsparam_flag	("noblock_validity",	Opt_noblock_validity),
1826 	fsparam_u32	("inode_readahead_blks",
1827 						Opt_inode_readahead_blks),
1828 	fsparam_u32	("journal_ioprio",	Opt_journal_ioprio),
1829 	fsparam_u32	("auto_da_alloc",	Opt_auto_da_alloc),
1830 	fsparam_flag	("auto_da_alloc",	Opt_auto_da_alloc),
1831 	fsparam_flag	("noauto_da_alloc",	Opt_noauto_da_alloc),
1832 	fsparam_flag	("dioread_nolock",	Opt_dioread_nolock),
1833 	fsparam_flag	("nodioread_nolock",	Opt_dioread_lock),
1834 	fsparam_flag	("dioread_lock",	Opt_dioread_lock),
1835 	fsparam_flag	("discard",		Opt_discard),
1836 	fsparam_flag	("nodiscard",		Opt_nodiscard),
1837 	fsparam_u32	("init_itable",		Opt_init_itable),
1838 	fsparam_flag	("init_itable",		Opt_init_itable),
1839 	fsparam_flag	("noinit_itable",	Opt_noinit_itable),
1840 #ifdef CONFIG_EXT4_DEBUG
1841 	fsparam_flag	("fc_debug_force",	Opt_fc_debug_force),
1842 	fsparam_u32	("fc_debug_max_replay",	Opt_fc_debug_max_replay),
1843 #endif
1844 	fsparam_u32	("max_dir_size_kb",	Opt_max_dir_size_kb),
1845 	fsparam_flag	("test_dummy_encryption",
1846 						Opt_test_dummy_encryption),
1847 	fsparam_string	("test_dummy_encryption",
1848 						Opt_test_dummy_encryption),
1849 	fsparam_flag	("inlinecrypt",		Opt_inlinecrypt),
1850 	fsparam_flag	("nombcache",		Opt_nombcache),
1851 	fsparam_flag	("no_mbcache",		Opt_nombcache),	/* for backward compatibility */
1852 	fsparam_flag	("prefetch_block_bitmaps",
1853 						Opt_removed),
1854 	fsparam_flag	("no_prefetch_block_bitmaps",
1855 						Opt_no_prefetch_block_bitmaps),
1856 	fsparam_s32	("mb_optimize_scan",	Opt_mb_optimize_scan),
1857 	fsparam_string	("check",		Opt_removed),	/* mount option from ext2/3 */
1858 	fsparam_flag	("nocheck",		Opt_removed),	/* mount option from ext2/3 */
1859 	fsparam_flag	("reservation",		Opt_removed),	/* mount option from ext2/3 */
1860 	fsparam_flag	("noreservation",	Opt_removed),	/* mount option from ext2/3 */
1861 	fsparam_u32	("journal",		Opt_removed),	/* mount option from ext2/3 */
1862 	{}
1863 };
1864 
1865 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1866 #define DEFAULT_MB_OPTIMIZE_SCAN	(-1)
1867 
1868 static const char deprecated_msg[] =
1869 	"Mount option \"%s\" will be removed by %s\n"
1870 	"Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1871 
1872 #define MOPT_SET	0x0001
1873 #define MOPT_CLEAR	0x0002
1874 #define MOPT_NOSUPPORT	0x0004
1875 #define MOPT_EXPLICIT	0x0008
1876 #ifdef CONFIG_QUOTA
1877 #define MOPT_Q		0
1878 #define MOPT_QFMT	0x0010
1879 #else
1880 #define MOPT_Q		MOPT_NOSUPPORT
1881 #define MOPT_QFMT	MOPT_NOSUPPORT
1882 #endif
1883 #define MOPT_NO_EXT2	0x0020
1884 #define MOPT_NO_EXT3	0x0040
1885 #define MOPT_EXT4_ONLY	(MOPT_NO_EXT2 | MOPT_NO_EXT3)
1886 #define MOPT_SKIP	0x0080
1887 #define	MOPT_2		0x0100
1888 
1889 static const struct mount_opts {
1890 	int	token;
1891 	int	mount_opt;
1892 	int	flags;
1893 } ext4_mount_opts[] = {
1894 	{Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1895 	{Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1896 	{Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1897 	{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1898 	{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1899 	{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1900 	{Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1901 	 MOPT_EXT4_ONLY | MOPT_SET},
1902 	{Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1903 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1904 	{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1905 	{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1906 	{Opt_delalloc, EXT4_MOUNT_DELALLOC,
1907 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1908 	{Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1909 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1910 	{Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1911 	{Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1912 	{Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1913 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1914 	{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1915 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1916 	{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1917 				    EXT4_MOUNT_JOURNAL_CHECKSUM),
1918 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1919 	{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1920 	{Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1921 	{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1922 	{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1923 	{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1924 	{Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1925 	{Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1926 	{Opt_dax_type, 0, MOPT_EXT4_ONLY},
1927 	{Opt_journal_dev, 0, MOPT_NO_EXT2},
1928 	{Opt_journal_path, 0, MOPT_NO_EXT2},
1929 	{Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1930 	{Opt_data, 0, MOPT_NO_EXT2},
1931 	{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1932 	{Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1933 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1934 	{Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1935 	{Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1936 #else
1937 	{Opt_acl, 0, MOPT_NOSUPPORT},
1938 	{Opt_noacl, 0, MOPT_NOSUPPORT},
1939 #endif
1940 	{Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1941 	{Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1942 	{Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1943 	{Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1944 							MOPT_SET | MOPT_Q},
1945 	{Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1946 							MOPT_SET | MOPT_Q},
1947 	{Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1948 							MOPT_SET | MOPT_Q},
1949 	{Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1950 		       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1951 							MOPT_CLEAR | MOPT_Q},
1952 	{Opt_usrjquota, 0, MOPT_Q},
1953 	{Opt_grpjquota, 0, MOPT_Q},
1954 	{Opt_jqfmt, 0, MOPT_QFMT},
1955 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1956 	{Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1957 	 MOPT_SET},
1958 #ifdef CONFIG_EXT4_DEBUG
1959 	{Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1960 	 MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1961 #endif
1962 	{Opt_err, 0, 0}
1963 };
1964 
1965 #ifdef CONFIG_UNICODE
1966 static const struct ext4_sb_encodings {
1967 	__u16 magic;
1968 	char *name;
1969 	unsigned int version;
1970 } ext4_sb_encoding_map[] = {
1971 	{EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1972 };
1973 
1974 static const struct ext4_sb_encodings *
1975 ext4_sb_read_encoding(const struct ext4_super_block *es)
1976 {
1977 	__u16 magic = le16_to_cpu(es->s_encoding);
1978 	int i;
1979 
1980 	for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1981 		if (magic == ext4_sb_encoding_map[i].magic)
1982 			return &ext4_sb_encoding_map[i];
1983 
1984 	return NULL;
1985 }
1986 #endif
1987 
1988 static int ext4_set_test_dummy_encryption(struct super_block *sb, char *arg)
1989 {
1990 #ifdef CONFIG_FS_ENCRYPTION
1991 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1992 	int err;
1993 
1994 	err = fscrypt_set_test_dummy_encryption(sb, arg,
1995 						&sbi->s_dummy_enc_policy);
1996 	if (err) {
1997 		ext4_msg(sb, KERN_WARNING,
1998 			 "Error while setting test dummy encryption [%d]", err);
1999 		return err;
2000 	}
2001 	ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2002 #endif
2003 	return 0;
2004 }
2005 
2006 #define EXT4_SPEC_JQUOTA			(1 <<  0)
2007 #define EXT4_SPEC_JQFMT				(1 <<  1)
2008 #define EXT4_SPEC_DATAJ				(1 <<  2)
2009 #define EXT4_SPEC_SB_BLOCK			(1 <<  3)
2010 #define EXT4_SPEC_JOURNAL_DEV			(1 <<  4)
2011 #define EXT4_SPEC_JOURNAL_IOPRIO		(1 <<  5)
2012 #define EXT4_SPEC_DUMMY_ENCRYPTION		(1 <<  6)
2013 #define EXT4_SPEC_s_want_extra_isize		(1 <<  7)
2014 #define EXT4_SPEC_s_max_batch_time		(1 <<  8)
2015 #define EXT4_SPEC_s_min_batch_time		(1 <<  9)
2016 #define EXT4_SPEC_s_inode_readahead_blks	(1 << 10)
2017 #define EXT4_SPEC_s_li_wait_mult		(1 << 11)
2018 #define EXT4_SPEC_s_max_dir_size_kb		(1 << 12)
2019 #define EXT4_SPEC_s_stripe			(1 << 13)
2020 #define EXT4_SPEC_s_resuid			(1 << 14)
2021 #define EXT4_SPEC_s_resgid			(1 << 15)
2022 #define EXT4_SPEC_s_commit_interval		(1 << 16)
2023 #define EXT4_SPEC_s_fc_debug_max_replay		(1 << 17)
2024 #define EXT4_SPEC_s_sb_block			(1 << 18)
2025 
2026 struct ext4_fs_context {
2027 	char		*s_qf_names[EXT4_MAXQUOTAS];
2028 	char		*test_dummy_enc_arg;
2029 	int		s_jquota_fmt;	/* Format of quota to use */
2030 	int		mb_optimize_scan;
2031 #ifdef CONFIG_EXT4_DEBUG
2032 	int s_fc_debug_max_replay;
2033 #endif
2034 	unsigned short	qname_spec;
2035 	unsigned long	vals_s_flags;	/* Bits to set in s_flags */
2036 	unsigned long	mask_s_flags;	/* Bits changed in s_flags */
2037 	unsigned long	journal_devnum;
2038 	unsigned long	s_commit_interval;
2039 	unsigned long	s_stripe;
2040 	unsigned int	s_inode_readahead_blks;
2041 	unsigned int	s_want_extra_isize;
2042 	unsigned int	s_li_wait_mult;
2043 	unsigned int	s_max_dir_size_kb;
2044 	unsigned int	journal_ioprio;
2045 	unsigned int	vals_s_mount_opt;
2046 	unsigned int	mask_s_mount_opt;
2047 	unsigned int	vals_s_mount_opt2;
2048 	unsigned int	mask_s_mount_opt2;
2049 	unsigned int	vals_s_mount_flags;
2050 	unsigned int	mask_s_mount_flags;
2051 	unsigned int	opt_flags;	/* MOPT flags */
2052 	unsigned int	spec;
2053 	u32		s_max_batch_time;
2054 	u32		s_min_batch_time;
2055 	kuid_t		s_resuid;
2056 	kgid_t		s_resgid;
2057 	ext4_fsblk_t	s_sb_block;
2058 };
2059 
2060 static void ext4_fc_free(struct fs_context *fc)
2061 {
2062 	struct ext4_fs_context *ctx = fc->fs_private;
2063 	int i;
2064 
2065 	if (!ctx)
2066 		return;
2067 
2068 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
2069 		kfree(ctx->s_qf_names[i]);
2070 
2071 	kfree(ctx->test_dummy_enc_arg);
2072 	kfree(ctx);
2073 }
2074 
2075 int ext4_init_fs_context(struct fs_context *fc)
2076 {
2077 	struct ext4_fs_context *ctx;
2078 
2079 	ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2080 	if (!ctx)
2081 		return -ENOMEM;
2082 
2083 	fc->fs_private = ctx;
2084 	fc->ops = &ext4_context_ops;
2085 
2086 	return 0;
2087 }
2088 
2089 #ifdef CONFIG_QUOTA
2090 /*
2091  * Note the name of the specified quota file.
2092  */
2093 static int note_qf_name(struct fs_context *fc, int qtype,
2094 		       struct fs_parameter *param)
2095 {
2096 	struct ext4_fs_context *ctx = fc->fs_private;
2097 	char *qname;
2098 
2099 	if (param->size < 1) {
2100 		ext4_msg(NULL, KERN_ERR, "Missing quota name");
2101 		return -EINVAL;
2102 	}
2103 	if (strchr(param->string, '/')) {
2104 		ext4_msg(NULL, KERN_ERR,
2105 			 "quotafile must be on filesystem root");
2106 		return -EINVAL;
2107 	}
2108 	if (ctx->s_qf_names[qtype]) {
2109 		if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2110 			ext4_msg(NULL, KERN_ERR,
2111 				 "%s quota file already specified",
2112 				 QTYPE2NAME(qtype));
2113 			return -EINVAL;
2114 		}
2115 		return 0;
2116 	}
2117 
2118 	qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2119 	if (!qname) {
2120 		ext4_msg(NULL, KERN_ERR,
2121 			 "Not enough memory for storing quotafile name");
2122 		return -ENOMEM;
2123 	}
2124 	ctx->s_qf_names[qtype] = qname;
2125 	ctx->qname_spec |= 1 << qtype;
2126 	ctx->spec |= EXT4_SPEC_JQUOTA;
2127 	return 0;
2128 }
2129 
2130 /*
2131  * Clear the name of the specified quota file.
2132  */
2133 static int unnote_qf_name(struct fs_context *fc, int qtype)
2134 {
2135 	struct ext4_fs_context *ctx = fc->fs_private;
2136 
2137 	if (ctx->s_qf_names[qtype])
2138 		kfree(ctx->s_qf_names[qtype]);
2139 
2140 	ctx->s_qf_names[qtype] = NULL;
2141 	ctx->qname_spec |= 1 << qtype;
2142 	ctx->spec |= EXT4_SPEC_JQUOTA;
2143 	return 0;
2144 }
2145 #endif
2146 
2147 #define EXT4_SET_CTX(name)						\
2148 static inline void ctx_set_##name(struct ext4_fs_context *ctx,		\
2149 				  unsigned long flag)			\
2150 {									\
2151 	ctx->mask_s_##name |= flag;					\
2152 	ctx->vals_s_##name |= flag;					\
2153 }									\
2154 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,	\
2155 				    unsigned long flag)			\
2156 {									\
2157 	ctx->mask_s_##name |= flag;					\
2158 	ctx->vals_s_##name &= ~flag;					\
2159 }									\
2160 static inline unsigned long						\
2161 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)	\
2162 {									\
2163 	return (ctx->vals_s_##name & flag);				\
2164 }									\
2165 
2166 EXT4_SET_CTX(flags);
2167 EXT4_SET_CTX(mount_opt);
2168 EXT4_SET_CTX(mount_opt2);
2169 EXT4_SET_CTX(mount_flags);
2170 
2171 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2172 {
2173 	struct ext4_fs_context *ctx = fc->fs_private;
2174 	struct fs_parse_result result;
2175 	const struct mount_opts *m;
2176 	int is_remount;
2177 	kuid_t uid;
2178 	kgid_t gid;
2179 	int token;
2180 
2181 	token = fs_parse(fc, ext4_param_specs, param, &result);
2182 	if (token < 0)
2183 		return token;
2184 	is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2185 
2186 	for (m = ext4_mount_opts; m->token != Opt_err; m++)
2187 		if (token == m->token)
2188 			break;
2189 
2190 	ctx->opt_flags |= m->flags;
2191 
2192 	if (m->flags & MOPT_EXPLICIT) {
2193 		if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2194 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2195 		} else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2196 			ctx_set_mount_opt2(ctx,
2197 				       EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2198 		} else
2199 			return -EINVAL;
2200 	}
2201 
2202 	if (m->flags & MOPT_NOSUPPORT) {
2203 		ext4_msg(NULL, KERN_ERR, "%s option not supported",
2204 			 param->key);
2205 		return 0;
2206 	}
2207 
2208 	switch (token) {
2209 #ifdef CONFIG_QUOTA
2210 	case Opt_usrjquota:
2211 		if (!*param->string)
2212 			return unnote_qf_name(fc, USRQUOTA);
2213 		else
2214 			return note_qf_name(fc, USRQUOTA, param);
2215 	case Opt_grpjquota:
2216 		if (!*param->string)
2217 			return unnote_qf_name(fc, GRPQUOTA);
2218 		else
2219 			return note_qf_name(fc, GRPQUOTA, param);
2220 #endif
2221 	case Opt_noacl:
2222 	case Opt_nouser_xattr:
2223 		ext4_msg(NULL, KERN_WARNING, deprecated_msg, param->key, "3.5");
2224 		break;
2225 	case Opt_sb:
2226 		if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2227 			ext4_msg(NULL, KERN_WARNING,
2228 				 "Ignoring %s option on remount", param->key);
2229 		} else {
2230 			ctx->s_sb_block = result.uint_32;
2231 			ctx->spec |= EXT4_SPEC_s_sb_block;
2232 		}
2233 		return 0;
2234 	case Opt_removed:
2235 		ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2236 			 param->key);
2237 		return 0;
2238 	case Opt_abort:
2239 		ctx_set_mount_flags(ctx, EXT4_MF_FS_ABORTED);
2240 		return 0;
2241 	case Opt_i_version:
2242 		ext4_msg(NULL, KERN_WARNING, deprecated_msg, param->key, "5.20");
2243 		ext4_msg(NULL, KERN_WARNING, "Use iversion instead\n");
2244 		ctx_set_flags(ctx, SB_I_VERSION);
2245 		return 0;
2246 	case Opt_inlinecrypt:
2247 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2248 		ctx_set_flags(ctx, SB_INLINECRYPT);
2249 #else
2250 		ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2251 #endif
2252 		return 0;
2253 	case Opt_errors:
2254 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2255 		ctx_set_mount_opt(ctx, result.uint_32);
2256 		return 0;
2257 #ifdef CONFIG_QUOTA
2258 	case Opt_jqfmt:
2259 		ctx->s_jquota_fmt = result.uint_32;
2260 		ctx->spec |= EXT4_SPEC_JQFMT;
2261 		return 0;
2262 #endif
2263 	case Opt_data:
2264 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2265 		ctx_set_mount_opt(ctx, result.uint_32);
2266 		ctx->spec |= EXT4_SPEC_DATAJ;
2267 		return 0;
2268 	case Opt_commit:
2269 		if (result.uint_32 == 0)
2270 			ctx->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE;
2271 		else if (result.uint_32 > INT_MAX / HZ) {
2272 			ext4_msg(NULL, KERN_ERR,
2273 				 "Invalid commit interval %d, "
2274 				 "must be smaller than %d",
2275 				 result.uint_32, INT_MAX / HZ);
2276 			return -EINVAL;
2277 		}
2278 		ctx->s_commit_interval = HZ * result.uint_32;
2279 		ctx->spec |= EXT4_SPEC_s_commit_interval;
2280 		return 0;
2281 	case Opt_debug_want_extra_isize:
2282 		if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2283 			ext4_msg(NULL, KERN_ERR,
2284 				 "Invalid want_extra_isize %d", result.uint_32);
2285 			return -EINVAL;
2286 		}
2287 		ctx->s_want_extra_isize = result.uint_32;
2288 		ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2289 		return 0;
2290 	case Opt_max_batch_time:
2291 		ctx->s_max_batch_time = result.uint_32;
2292 		ctx->spec |= EXT4_SPEC_s_max_batch_time;
2293 		return 0;
2294 	case Opt_min_batch_time:
2295 		ctx->s_min_batch_time = result.uint_32;
2296 		ctx->spec |= EXT4_SPEC_s_min_batch_time;
2297 		return 0;
2298 	case Opt_inode_readahead_blks:
2299 		if (result.uint_32 &&
2300 		    (result.uint_32 > (1 << 30) ||
2301 		     !is_power_of_2(result.uint_32))) {
2302 			ext4_msg(NULL, KERN_ERR,
2303 				 "EXT4-fs: inode_readahead_blks must be "
2304 				 "0 or a power of 2 smaller than 2^31");
2305 			return -EINVAL;
2306 		}
2307 		ctx->s_inode_readahead_blks = result.uint_32;
2308 		ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2309 		return 0;
2310 	case Opt_init_itable:
2311 		ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2312 		ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2313 		if (param->type == fs_value_is_string)
2314 			ctx->s_li_wait_mult = result.uint_32;
2315 		ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2316 		return 0;
2317 	case Opt_max_dir_size_kb:
2318 		ctx->s_max_dir_size_kb = result.uint_32;
2319 		ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2320 		return 0;
2321 #ifdef CONFIG_EXT4_DEBUG
2322 	case Opt_fc_debug_max_replay:
2323 		ctx->s_fc_debug_max_replay = result.uint_32;
2324 		ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2325 		return 0;
2326 #endif
2327 	case Opt_stripe:
2328 		ctx->s_stripe = result.uint_32;
2329 		ctx->spec |= EXT4_SPEC_s_stripe;
2330 		return 0;
2331 	case Opt_resuid:
2332 		uid = make_kuid(current_user_ns(), result.uint_32);
2333 		if (!uid_valid(uid)) {
2334 			ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2335 				 result.uint_32);
2336 			return -EINVAL;
2337 		}
2338 		ctx->s_resuid = uid;
2339 		ctx->spec |= EXT4_SPEC_s_resuid;
2340 		return 0;
2341 	case Opt_resgid:
2342 		gid = make_kgid(current_user_ns(), result.uint_32);
2343 		if (!gid_valid(gid)) {
2344 			ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2345 				 result.uint_32);
2346 			return -EINVAL;
2347 		}
2348 		ctx->s_resgid = gid;
2349 		ctx->spec |= EXT4_SPEC_s_resgid;
2350 		return 0;
2351 	case Opt_journal_dev:
2352 		if (is_remount) {
2353 			ext4_msg(NULL, KERN_ERR,
2354 				 "Cannot specify journal on remount");
2355 			return -EINVAL;
2356 		}
2357 		ctx->journal_devnum = result.uint_32;
2358 		ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2359 		return 0;
2360 	case Opt_journal_path:
2361 	{
2362 		struct inode *journal_inode;
2363 		struct path path;
2364 		int error;
2365 
2366 		if (is_remount) {
2367 			ext4_msg(NULL, KERN_ERR,
2368 				 "Cannot specify journal on remount");
2369 			return -EINVAL;
2370 		}
2371 
2372 		error = fs_lookup_param(fc, param, 1, &path);
2373 		if (error) {
2374 			ext4_msg(NULL, KERN_ERR, "error: could not find "
2375 				 "journal device path");
2376 			return -EINVAL;
2377 		}
2378 
2379 		journal_inode = d_inode(path.dentry);
2380 		ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2381 		ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2382 		path_put(&path);
2383 		return 0;
2384 	}
2385 	case Opt_journal_ioprio:
2386 		if (result.uint_32 > 7) {
2387 			ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2388 				 " (must be 0-7)");
2389 			return -EINVAL;
2390 		}
2391 		ctx->journal_ioprio =
2392 			IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2393 		ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2394 		return 0;
2395 	case Opt_test_dummy_encryption:
2396 #ifdef CONFIG_FS_ENCRYPTION
2397 		if (param->type == fs_value_is_flag) {
2398 			ctx->spec |= EXT4_SPEC_DUMMY_ENCRYPTION;
2399 			ctx->test_dummy_enc_arg = NULL;
2400 			return 0;
2401 		}
2402 		if (*param->string &&
2403 		    !(!strcmp(param->string, "v1") ||
2404 		      !strcmp(param->string, "v2"))) {
2405 			ext4_msg(NULL, KERN_WARNING,
2406 				 "Value of option \"%s\" is unrecognized",
2407 				 param->key);
2408 			return -EINVAL;
2409 		}
2410 		ctx->spec |= EXT4_SPEC_DUMMY_ENCRYPTION;
2411 		ctx->test_dummy_enc_arg = kmemdup_nul(param->string, param->size,
2412 						      GFP_KERNEL);
2413 #else
2414 		ext4_msg(NULL, KERN_WARNING,
2415 			 "Test dummy encryption mount option ignored");
2416 #endif
2417 		return 0;
2418 	case Opt_dax:
2419 	case Opt_dax_type:
2420 #ifdef CONFIG_FS_DAX
2421 	{
2422 		int type = (token == Opt_dax) ?
2423 			   Opt_dax : result.uint_32;
2424 
2425 		switch (type) {
2426 		case Opt_dax:
2427 		case Opt_dax_always:
2428 			ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2429 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2430 			break;
2431 		case Opt_dax_never:
2432 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2433 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2434 			break;
2435 		case Opt_dax_inode:
2436 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2437 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2438 			/* Strictly for printing options */
2439 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2440 			break;
2441 		}
2442 		return 0;
2443 	}
2444 #else
2445 		ext4_msg(NULL, KERN_INFO, "dax option not supported");
2446 		return -EINVAL;
2447 #endif
2448 	case Opt_data_err:
2449 		if (result.uint_32 == Opt_data_err_abort)
2450 			ctx_set_mount_opt(ctx, m->mount_opt);
2451 		else if (result.uint_32 == Opt_data_err_ignore)
2452 			ctx_clear_mount_opt(ctx, m->mount_opt);
2453 		return 0;
2454 	case Opt_mb_optimize_scan:
2455 		if (result.int_32 != 0 && result.int_32 != 1) {
2456 			ext4_msg(NULL, KERN_WARNING,
2457 				 "mb_optimize_scan should be set to 0 or 1.");
2458 			return -EINVAL;
2459 		}
2460 		ctx->mb_optimize_scan = result.int_32;
2461 		return 0;
2462 	}
2463 
2464 	/*
2465 	 * At this point we should only be getting options requiring MOPT_SET,
2466 	 * or MOPT_CLEAR. Anything else is a bug
2467 	 */
2468 	if (m->token == Opt_err) {
2469 		ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2470 			 param->key);
2471 		WARN_ON(1);
2472 		return -EINVAL;
2473 	}
2474 
2475 	else {
2476 		unsigned int set = 0;
2477 
2478 		if ((param->type == fs_value_is_flag) ||
2479 		    result.uint_32 > 0)
2480 			set = 1;
2481 
2482 		if (m->flags & MOPT_CLEAR)
2483 			set = !set;
2484 		else if (unlikely(!(m->flags & MOPT_SET))) {
2485 			ext4_msg(NULL, KERN_WARNING,
2486 				 "buggy handling of option %s",
2487 				 param->key);
2488 			WARN_ON(1);
2489 			return -EINVAL;
2490 		}
2491 		if (m->flags & MOPT_2) {
2492 			if (set != 0)
2493 				ctx_set_mount_opt2(ctx, m->mount_opt);
2494 			else
2495 				ctx_clear_mount_opt2(ctx, m->mount_opt);
2496 		} else {
2497 			if (set != 0)
2498 				ctx_set_mount_opt(ctx, m->mount_opt);
2499 			else
2500 				ctx_clear_mount_opt(ctx, m->mount_opt);
2501 		}
2502 	}
2503 
2504 	return 0;
2505 }
2506 
2507 static int parse_options(struct fs_context *fc, char *options)
2508 {
2509 	struct fs_parameter param;
2510 	int ret;
2511 	char *key;
2512 
2513 	if (!options)
2514 		return 0;
2515 
2516 	while ((key = strsep(&options, ",")) != NULL) {
2517 		if (*key) {
2518 			size_t v_len = 0;
2519 			char *value = strchr(key, '=');
2520 
2521 			param.type = fs_value_is_flag;
2522 			param.string = NULL;
2523 
2524 			if (value) {
2525 				if (value == key)
2526 					continue;
2527 
2528 				*value++ = 0;
2529 				v_len = strlen(value);
2530 				param.string = kmemdup_nul(value, v_len,
2531 							   GFP_KERNEL);
2532 				if (!param.string)
2533 					return -ENOMEM;
2534 				param.type = fs_value_is_string;
2535 			}
2536 
2537 			param.key = key;
2538 			param.size = v_len;
2539 
2540 			ret = ext4_parse_param(fc, &param);
2541 			if (param.string)
2542 				kfree(param.string);
2543 			if (ret < 0)
2544 				return ret;
2545 		}
2546 	}
2547 
2548 	ret = ext4_validate_options(fc);
2549 	if (ret < 0)
2550 		return ret;
2551 
2552 	return 0;
2553 }
2554 
2555 static int parse_apply_sb_mount_options(struct super_block *sb,
2556 					struct ext4_fs_context *m_ctx)
2557 {
2558 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2559 	char *s_mount_opts = NULL;
2560 	struct ext4_fs_context *s_ctx = NULL;
2561 	struct fs_context *fc = NULL;
2562 	int ret = -ENOMEM;
2563 
2564 	if (!sbi->s_es->s_mount_opts[0])
2565 		return 0;
2566 
2567 	s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2568 				sizeof(sbi->s_es->s_mount_opts),
2569 				GFP_KERNEL);
2570 	if (!s_mount_opts)
2571 		return ret;
2572 
2573 	fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2574 	if (!fc)
2575 		goto out_free;
2576 
2577 	s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2578 	if (!s_ctx)
2579 		goto out_free;
2580 
2581 	fc->fs_private = s_ctx;
2582 	fc->s_fs_info = sbi;
2583 
2584 	ret = parse_options(fc, s_mount_opts);
2585 	if (ret < 0)
2586 		goto parse_failed;
2587 
2588 	ret = ext4_check_opt_consistency(fc, sb);
2589 	if (ret < 0) {
2590 parse_failed:
2591 		ext4_msg(sb, KERN_WARNING,
2592 			 "failed to parse options in superblock: %s",
2593 			 s_mount_opts);
2594 		ret = 0;
2595 		goto out_free;
2596 	}
2597 
2598 	if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2599 		m_ctx->journal_devnum = s_ctx->journal_devnum;
2600 	if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2601 		m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2602 
2603 	ret = ext4_apply_options(fc, sb);
2604 
2605 out_free:
2606 	kfree(s_ctx);
2607 	kfree(fc);
2608 	kfree(s_mount_opts);
2609 	return ret;
2610 }
2611 
2612 static void ext4_apply_quota_options(struct fs_context *fc,
2613 				     struct super_block *sb)
2614 {
2615 #ifdef CONFIG_QUOTA
2616 	bool quota_feature = ext4_has_feature_quota(sb);
2617 	struct ext4_fs_context *ctx = fc->fs_private;
2618 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2619 	char *qname;
2620 	int i;
2621 
2622 	if (quota_feature)
2623 		return;
2624 
2625 	if (ctx->spec & EXT4_SPEC_JQUOTA) {
2626 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2627 			if (!(ctx->qname_spec & (1 << i)))
2628 				continue;
2629 
2630 			qname = ctx->s_qf_names[i]; /* May be NULL */
2631 			if (qname)
2632 				set_opt(sb, QUOTA);
2633 			ctx->s_qf_names[i] = NULL;
2634 			qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2635 						lockdep_is_held(&sb->s_umount));
2636 			if (qname)
2637 				kfree_rcu(qname);
2638 		}
2639 	}
2640 
2641 	if (ctx->spec & EXT4_SPEC_JQFMT)
2642 		sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2643 #endif
2644 }
2645 
2646 /*
2647  * Check quota settings consistency.
2648  */
2649 static int ext4_check_quota_consistency(struct fs_context *fc,
2650 					struct super_block *sb)
2651 {
2652 #ifdef CONFIG_QUOTA
2653 	struct ext4_fs_context *ctx = fc->fs_private;
2654 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2655 	bool quota_feature = ext4_has_feature_quota(sb);
2656 	bool quota_loaded = sb_any_quota_loaded(sb);
2657 	bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2658 	int quota_flags, i;
2659 
2660 	/*
2661 	 * We do the test below only for project quotas. 'usrquota' and
2662 	 * 'grpquota' mount options are allowed even without quota feature
2663 	 * to support legacy quotas in quota files.
2664 	 */
2665 	if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2666 	    !ext4_has_feature_project(sb)) {
2667 		ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2668 			 "Cannot enable project quota enforcement.");
2669 		return -EINVAL;
2670 	}
2671 
2672 	quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2673 		      EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2674 	if (quota_loaded &&
2675 	    ctx->mask_s_mount_opt & quota_flags &&
2676 	    !ctx_test_mount_opt(ctx, quota_flags))
2677 		goto err_quota_change;
2678 
2679 	if (ctx->spec & EXT4_SPEC_JQUOTA) {
2680 
2681 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2682 			if (!(ctx->qname_spec & (1 << i)))
2683 				continue;
2684 
2685 			if (quota_loaded &&
2686 			    !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2687 				goto err_jquota_change;
2688 
2689 			if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2690 			    strcmp(get_qf_name(sb, sbi, i),
2691 				   ctx->s_qf_names[i]) != 0)
2692 				goto err_jquota_specified;
2693 		}
2694 
2695 		if (quota_feature) {
2696 			ext4_msg(NULL, KERN_INFO,
2697 				 "Journaled quota options ignored when "
2698 				 "QUOTA feature is enabled");
2699 			return 0;
2700 		}
2701 	}
2702 
2703 	if (ctx->spec & EXT4_SPEC_JQFMT) {
2704 		if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2705 			goto err_jquota_change;
2706 		if (quota_feature) {
2707 			ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2708 				 "ignored when QUOTA feature is enabled");
2709 			return 0;
2710 		}
2711 	}
2712 
2713 	/* Make sure we don't mix old and new quota format */
2714 	usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2715 		       ctx->s_qf_names[USRQUOTA]);
2716 	grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2717 		       ctx->s_qf_names[GRPQUOTA]);
2718 
2719 	usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2720 		    test_opt(sb, USRQUOTA));
2721 
2722 	grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2723 		    test_opt(sb, GRPQUOTA));
2724 
2725 	if (usr_qf_name) {
2726 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2727 		usrquota = false;
2728 	}
2729 	if (grp_qf_name) {
2730 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2731 		grpquota = false;
2732 	}
2733 
2734 	if (usr_qf_name || grp_qf_name) {
2735 		if (usrquota || grpquota) {
2736 			ext4_msg(NULL, KERN_ERR, "old and new quota "
2737 				 "format mixing");
2738 			return -EINVAL;
2739 		}
2740 
2741 		if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2742 			ext4_msg(NULL, KERN_ERR, "journaled quota format "
2743 				 "not specified");
2744 			return -EINVAL;
2745 		}
2746 	}
2747 
2748 	return 0;
2749 
2750 err_quota_change:
2751 	ext4_msg(NULL, KERN_ERR,
2752 		 "Cannot change quota options when quota turned on");
2753 	return -EINVAL;
2754 err_jquota_change:
2755 	ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2756 		 "options when quota turned on");
2757 	return -EINVAL;
2758 err_jquota_specified:
2759 	ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2760 		 QTYPE2NAME(i));
2761 	return -EINVAL;
2762 #else
2763 	return 0;
2764 #endif
2765 }
2766 
2767 static int ext4_check_opt_consistency(struct fs_context *fc,
2768 				      struct super_block *sb)
2769 {
2770 	struct ext4_fs_context *ctx = fc->fs_private;
2771 	struct ext4_sb_info *sbi = fc->s_fs_info;
2772 	int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2773 
2774 	if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2775 		ext4_msg(NULL, KERN_ERR,
2776 			 "Mount option(s) incompatible with ext2");
2777 		return -EINVAL;
2778 	}
2779 	if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2780 		ext4_msg(NULL, KERN_ERR,
2781 			 "Mount option(s) incompatible with ext3");
2782 		return -EINVAL;
2783 	}
2784 
2785 	if (ctx->s_want_extra_isize >
2786 	    (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2787 		ext4_msg(NULL, KERN_ERR,
2788 			 "Invalid want_extra_isize %d",
2789 			 ctx->s_want_extra_isize);
2790 		return -EINVAL;
2791 	}
2792 
2793 	if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DIOREAD_NOLOCK)) {
2794 		int blocksize =
2795 			BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2796 		if (blocksize < PAGE_SIZE)
2797 			ext4_msg(NULL, KERN_WARNING, "Warning: mounting with an "
2798 				 "experimental mount option 'dioread_nolock' "
2799 				 "for blocksize < PAGE_SIZE");
2800 	}
2801 
2802 #ifdef CONFIG_FS_ENCRYPTION
2803 	/*
2804 	 * This mount option is just for testing, and it's not worthwhile to
2805 	 * implement the extra complexity (e.g. RCU protection) that would be
2806 	 * needed to allow it to be set or changed during remount.  We do allow
2807 	 * it to be specified during remount, but only if there is no change.
2808 	 */
2809 	if ((ctx->spec & EXT4_SPEC_DUMMY_ENCRYPTION) &&
2810 	    is_remount && !sbi->s_dummy_enc_policy.policy) {
2811 		ext4_msg(NULL, KERN_WARNING,
2812 			 "Can't set test_dummy_encryption on remount");
2813 		return -1;
2814 	}
2815 #endif
2816 
2817 	if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2818 		if (!sbi->s_journal) {
2819 			ext4_msg(NULL, KERN_WARNING,
2820 				 "Remounting file system with no journal "
2821 				 "so ignoring journalled data option");
2822 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2823 		} else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2824 			   test_opt(sb, DATA_FLAGS)) {
2825 			ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2826 				 "on remount");
2827 			return -EINVAL;
2828 		}
2829 	}
2830 
2831 	if (is_remount) {
2832 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2833 		    (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2834 			ext4_msg(NULL, KERN_ERR, "can't mount with "
2835 				 "both data=journal and dax");
2836 			return -EINVAL;
2837 		}
2838 
2839 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2840 		    (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2841 		     (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2842 fail_dax_change_remount:
2843 			ext4_msg(NULL, KERN_ERR, "can't change "
2844 				 "dax mount option while remounting");
2845 			return -EINVAL;
2846 		} else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2847 			 (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2848 			  (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2849 			goto fail_dax_change_remount;
2850 		} else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2851 			   ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2852 			    (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2853 			    !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2854 			goto fail_dax_change_remount;
2855 		}
2856 	}
2857 
2858 	return ext4_check_quota_consistency(fc, sb);
2859 }
2860 
2861 static int ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2862 {
2863 	struct ext4_fs_context *ctx = fc->fs_private;
2864 	struct ext4_sb_info *sbi = fc->s_fs_info;
2865 	int ret = 0;
2866 
2867 	sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2868 	sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2869 	sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2870 	sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2871 	sbi->s_mount_flags &= ~ctx->mask_s_mount_flags;
2872 	sbi->s_mount_flags |= ctx->vals_s_mount_flags;
2873 	sb->s_flags &= ~ctx->mask_s_flags;
2874 	sb->s_flags |= ctx->vals_s_flags;
2875 
2876 	/*
2877 	 * i_version differs from common mount option iversion so we have
2878 	 * to let vfs know that it was set, otherwise it would get cleared
2879 	 * on remount
2880 	 */
2881 	if (ctx->mask_s_flags & SB_I_VERSION)
2882 		fc->sb_flags |= SB_I_VERSION;
2883 
2884 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2885 	APPLY(s_commit_interval);
2886 	APPLY(s_stripe);
2887 	APPLY(s_max_batch_time);
2888 	APPLY(s_min_batch_time);
2889 	APPLY(s_want_extra_isize);
2890 	APPLY(s_inode_readahead_blks);
2891 	APPLY(s_max_dir_size_kb);
2892 	APPLY(s_li_wait_mult);
2893 	APPLY(s_resgid);
2894 	APPLY(s_resuid);
2895 
2896 #ifdef CONFIG_EXT4_DEBUG
2897 	APPLY(s_fc_debug_max_replay);
2898 #endif
2899 
2900 	ext4_apply_quota_options(fc, sb);
2901 
2902 	if (ctx->spec & EXT4_SPEC_DUMMY_ENCRYPTION)
2903 		ret = ext4_set_test_dummy_encryption(sb, ctx->test_dummy_enc_arg);
2904 
2905 	return ret;
2906 }
2907 
2908 
2909 static int ext4_validate_options(struct fs_context *fc)
2910 {
2911 #ifdef CONFIG_QUOTA
2912 	struct ext4_fs_context *ctx = fc->fs_private;
2913 	char *usr_qf_name, *grp_qf_name;
2914 
2915 	usr_qf_name = ctx->s_qf_names[USRQUOTA];
2916 	grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2917 
2918 	if (usr_qf_name || grp_qf_name) {
2919 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2920 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2921 
2922 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2923 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2924 
2925 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2926 		    ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2927 			ext4_msg(NULL, KERN_ERR, "old and new quota "
2928 				 "format mixing");
2929 			return -EINVAL;
2930 		}
2931 	}
2932 #endif
2933 	return 1;
2934 }
2935 
2936 static inline void ext4_show_quota_options(struct seq_file *seq,
2937 					   struct super_block *sb)
2938 {
2939 #if defined(CONFIG_QUOTA)
2940 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2941 	char *usr_qf_name, *grp_qf_name;
2942 
2943 	if (sbi->s_jquota_fmt) {
2944 		char *fmtname = "";
2945 
2946 		switch (sbi->s_jquota_fmt) {
2947 		case QFMT_VFS_OLD:
2948 			fmtname = "vfsold";
2949 			break;
2950 		case QFMT_VFS_V0:
2951 			fmtname = "vfsv0";
2952 			break;
2953 		case QFMT_VFS_V1:
2954 			fmtname = "vfsv1";
2955 			break;
2956 		}
2957 		seq_printf(seq, ",jqfmt=%s", fmtname);
2958 	}
2959 
2960 	rcu_read_lock();
2961 	usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2962 	grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2963 	if (usr_qf_name)
2964 		seq_show_option(seq, "usrjquota", usr_qf_name);
2965 	if (grp_qf_name)
2966 		seq_show_option(seq, "grpjquota", grp_qf_name);
2967 	rcu_read_unlock();
2968 #endif
2969 }
2970 
2971 static const char *token2str(int token)
2972 {
2973 	const struct fs_parameter_spec *spec;
2974 
2975 	for (spec = ext4_param_specs; spec->name != NULL; spec++)
2976 		if (spec->opt == token && !spec->type)
2977 			break;
2978 	return spec->name;
2979 }
2980 
2981 /*
2982  * Show an option if
2983  *  - it's set to a non-default value OR
2984  *  - if the per-sb default is different from the global default
2985  */
2986 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2987 			      int nodefs)
2988 {
2989 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2990 	struct ext4_super_block *es = sbi->s_es;
2991 	int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2992 	const struct mount_opts *m;
2993 	char sep = nodefs ? '\n' : ',';
2994 
2995 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2996 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2997 
2998 	if (sbi->s_sb_block != 1)
2999 		SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
3000 
3001 	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
3002 		int want_set = m->flags & MOPT_SET;
3003 		if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
3004 		    m->flags & MOPT_SKIP)
3005 			continue;
3006 		if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
3007 			continue; /* skip if same as the default */
3008 		if ((want_set &&
3009 		     (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
3010 		    (!want_set && (sbi->s_mount_opt & m->mount_opt)))
3011 			continue; /* select Opt_noFoo vs Opt_Foo */
3012 		SEQ_OPTS_PRINT("%s", token2str(m->token));
3013 	}
3014 
3015 	if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
3016 	    le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
3017 		SEQ_OPTS_PRINT("resuid=%u",
3018 				from_kuid_munged(&init_user_ns, sbi->s_resuid));
3019 	if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
3020 	    le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
3021 		SEQ_OPTS_PRINT("resgid=%u",
3022 				from_kgid_munged(&init_user_ns, sbi->s_resgid));
3023 	def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
3024 	if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
3025 		SEQ_OPTS_PUTS("errors=remount-ro");
3026 	if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
3027 		SEQ_OPTS_PUTS("errors=continue");
3028 	if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
3029 		SEQ_OPTS_PUTS("errors=panic");
3030 	if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
3031 		SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
3032 	if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
3033 		SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
3034 	if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
3035 		SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
3036 	if (sb->s_flags & SB_I_VERSION)
3037 		SEQ_OPTS_PUTS("i_version");
3038 	if (nodefs || sbi->s_stripe)
3039 		SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
3040 	if (nodefs || EXT4_MOUNT_DATA_FLAGS &
3041 			(sbi->s_mount_opt ^ def_mount_opt)) {
3042 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3043 			SEQ_OPTS_PUTS("data=journal");
3044 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3045 			SEQ_OPTS_PUTS("data=ordered");
3046 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
3047 			SEQ_OPTS_PUTS("data=writeback");
3048 	}
3049 	if (nodefs ||
3050 	    sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3051 		SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3052 			       sbi->s_inode_readahead_blks);
3053 
3054 	if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3055 		       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3056 		SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3057 	if (nodefs || sbi->s_max_dir_size_kb)
3058 		SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3059 	if (test_opt(sb, DATA_ERR_ABORT))
3060 		SEQ_OPTS_PUTS("data_err=abort");
3061 
3062 	fscrypt_show_test_dummy_encryption(seq, sep, sb);
3063 
3064 	if (sb->s_flags & SB_INLINECRYPT)
3065 		SEQ_OPTS_PUTS("inlinecrypt");
3066 
3067 	if (test_opt(sb, DAX_ALWAYS)) {
3068 		if (IS_EXT2_SB(sb))
3069 			SEQ_OPTS_PUTS("dax");
3070 		else
3071 			SEQ_OPTS_PUTS("dax=always");
3072 	} else if (test_opt2(sb, DAX_NEVER)) {
3073 		SEQ_OPTS_PUTS("dax=never");
3074 	} else if (test_opt2(sb, DAX_INODE)) {
3075 		SEQ_OPTS_PUTS("dax=inode");
3076 	}
3077 	ext4_show_quota_options(seq, sb);
3078 	return 0;
3079 }
3080 
3081 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3082 {
3083 	return _ext4_show_options(seq, root->d_sb, 0);
3084 }
3085 
3086 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3087 {
3088 	struct super_block *sb = seq->private;
3089 	int rc;
3090 
3091 	seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3092 	rc = _ext4_show_options(seq, sb, 1);
3093 	seq_puts(seq, "\n");
3094 	return rc;
3095 }
3096 
3097 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3098 			    int read_only)
3099 {
3100 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3101 	int err = 0;
3102 
3103 	if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3104 		ext4_msg(sb, KERN_ERR, "revision level too high, "
3105 			 "forcing read-only mode");
3106 		err = -EROFS;
3107 		goto done;
3108 	}
3109 	if (read_only)
3110 		goto done;
3111 	if (!(sbi->s_mount_state & EXT4_VALID_FS))
3112 		ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3113 			 "running e2fsck is recommended");
3114 	else if (sbi->s_mount_state & EXT4_ERROR_FS)
3115 		ext4_msg(sb, KERN_WARNING,
3116 			 "warning: mounting fs with errors, "
3117 			 "running e2fsck is recommended");
3118 	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3119 		 le16_to_cpu(es->s_mnt_count) >=
3120 		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3121 		ext4_msg(sb, KERN_WARNING,
3122 			 "warning: maximal mount count reached, "
3123 			 "running e2fsck is recommended");
3124 	else if (le32_to_cpu(es->s_checkinterval) &&
3125 		 (ext4_get_tstamp(es, s_lastcheck) +
3126 		  le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3127 		ext4_msg(sb, KERN_WARNING,
3128 			 "warning: checktime reached, "
3129 			 "running e2fsck is recommended");
3130 	if (!sbi->s_journal)
3131 		es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3132 	if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3133 		es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3134 	le16_add_cpu(&es->s_mnt_count, 1);
3135 	ext4_update_tstamp(es, s_mtime);
3136 	if (sbi->s_journal) {
3137 		ext4_set_feature_journal_needs_recovery(sb);
3138 		if (ext4_has_feature_orphan_file(sb))
3139 			ext4_set_feature_orphan_present(sb);
3140 	}
3141 
3142 	err = ext4_commit_super(sb);
3143 done:
3144 	if (test_opt(sb, DEBUG))
3145 		printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3146 				"bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3147 			sb->s_blocksize,
3148 			sbi->s_groups_count,
3149 			EXT4_BLOCKS_PER_GROUP(sb),
3150 			EXT4_INODES_PER_GROUP(sb),
3151 			sbi->s_mount_opt, sbi->s_mount_opt2);
3152 
3153 	cleancache_init_fs(sb);
3154 	return err;
3155 }
3156 
3157 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3158 {
3159 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3160 	struct flex_groups **old_groups, **new_groups;
3161 	int size, i, j;
3162 
3163 	if (!sbi->s_log_groups_per_flex)
3164 		return 0;
3165 
3166 	size = ext4_flex_group(sbi, ngroup - 1) + 1;
3167 	if (size <= sbi->s_flex_groups_allocated)
3168 		return 0;
3169 
3170 	new_groups = kvzalloc(roundup_pow_of_two(size *
3171 			      sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3172 	if (!new_groups) {
3173 		ext4_msg(sb, KERN_ERR,
3174 			 "not enough memory for %d flex group pointers", size);
3175 		return -ENOMEM;
3176 	}
3177 	for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3178 		new_groups[i] = kvzalloc(roundup_pow_of_two(
3179 					 sizeof(struct flex_groups)),
3180 					 GFP_KERNEL);
3181 		if (!new_groups[i]) {
3182 			for (j = sbi->s_flex_groups_allocated; j < i; j++)
3183 				kvfree(new_groups[j]);
3184 			kvfree(new_groups);
3185 			ext4_msg(sb, KERN_ERR,
3186 				 "not enough memory for %d flex groups", size);
3187 			return -ENOMEM;
3188 		}
3189 	}
3190 	rcu_read_lock();
3191 	old_groups = rcu_dereference(sbi->s_flex_groups);
3192 	if (old_groups)
3193 		memcpy(new_groups, old_groups,
3194 		       (sbi->s_flex_groups_allocated *
3195 			sizeof(struct flex_groups *)));
3196 	rcu_read_unlock();
3197 	rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3198 	sbi->s_flex_groups_allocated = size;
3199 	if (old_groups)
3200 		ext4_kvfree_array_rcu(old_groups);
3201 	return 0;
3202 }
3203 
3204 static int ext4_fill_flex_info(struct super_block *sb)
3205 {
3206 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3207 	struct ext4_group_desc *gdp = NULL;
3208 	struct flex_groups *fg;
3209 	ext4_group_t flex_group;
3210 	int i, err;
3211 
3212 	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3213 	if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3214 		sbi->s_log_groups_per_flex = 0;
3215 		return 1;
3216 	}
3217 
3218 	err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3219 	if (err)
3220 		goto failed;
3221 
3222 	for (i = 0; i < sbi->s_groups_count; i++) {
3223 		gdp = ext4_get_group_desc(sb, i, NULL);
3224 
3225 		flex_group = ext4_flex_group(sbi, i);
3226 		fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3227 		atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3228 		atomic64_add(ext4_free_group_clusters(sb, gdp),
3229 			     &fg->free_clusters);
3230 		atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3231 	}
3232 
3233 	return 1;
3234 failed:
3235 	return 0;
3236 }
3237 
3238 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3239 				   struct ext4_group_desc *gdp)
3240 {
3241 	int offset = offsetof(struct ext4_group_desc, bg_checksum);
3242 	__u16 crc = 0;
3243 	__le32 le_group = cpu_to_le32(block_group);
3244 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3245 
3246 	if (ext4_has_metadata_csum(sbi->s_sb)) {
3247 		/* Use new metadata_csum algorithm */
3248 		__u32 csum32;
3249 		__u16 dummy_csum = 0;
3250 
3251 		csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3252 				     sizeof(le_group));
3253 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3254 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3255 				     sizeof(dummy_csum));
3256 		offset += sizeof(dummy_csum);
3257 		if (offset < sbi->s_desc_size)
3258 			csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3259 					     sbi->s_desc_size - offset);
3260 
3261 		crc = csum32 & 0xFFFF;
3262 		goto out;
3263 	}
3264 
3265 	/* old crc16 code */
3266 	if (!ext4_has_feature_gdt_csum(sb))
3267 		return 0;
3268 
3269 	crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3270 	crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3271 	crc = crc16(crc, (__u8 *)gdp, offset);
3272 	offset += sizeof(gdp->bg_checksum); /* skip checksum */
3273 	/* for checksum of struct ext4_group_desc do the rest...*/
3274 	if (ext4_has_feature_64bit(sb) &&
3275 	    offset < le16_to_cpu(sbi->s_es->s_desc_size))
3276 		crc = crc16(crc, (__u8 *)gdp + offset,
3277 			    le16_to_cpu(sbi->s_es->s_desc_size) -
3278 				offset);
3279 
3280 out:
3281 	return cpu_to_le16(crc);
3282 }
3283 
3284 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3285 				struct ext4_group_desc *gdp)
3286 {
3287 	if (ext4_has_group_desc_csum(sb) &&
3288 	    (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3289 		return 0;
3290 
3291 	return 1;
3292 }
3293 
3294 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3295 			      struct ext4_group_desc *gdp)
3296 {
3297 	if (!ext4_has_group_desc_csum(sb))
3298 		return;
3299 	gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3300 }
3301 
3302 /* Called at mount-time, super-block is locked */
3303 static int ext4_check_descriptors(struct super_block *sb,
3304 				  ext4_fsblk_t sb_block,
3305 				  ext4_group_t *first_not_zeroed)
3306 {
3307 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3308 	ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3309 	ext4_fsblk_t last_block;
3310 	ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3311 	ext4_fsblk_t block_bitmap;
3312 	ext4_fsblk_t inode_bitmap;
3313 	ext4_fsblk_t inode_table;
3314 	int flexbg_flag = 0;
3315 	ext4_group_t i, grp = sbi->s_groups_count;
3316 
3317 	if (ext4_has_feature_flex_bg(sb))
3318 		flexbg_flag = 1;
3319 
3320 	ext4_debug("Checking group descriptors");
3321 
3322 	for (i = 0; i < sbi->s_groups_count; i++) {
3323 		struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3324 
3325 		if (i == sbi->s_groups_count - 1 || flexbg_flag)
3326 			last_block = ext4_blocks_count(sbi->s_es) - 1;
3327 		else
3328 			last_block = first_block +
3329 				(EXT4_BLOCKS_PER_GROUP(sb) - 1);
3330 
3331 		if ((grp == sbi->s_groups_count) &&
3332 		   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3333 			grp = i;
3334 
3335 		block_bitmap = ext4_block_bitmap(sb, gdp);
3336 		if (block_bitmap == sb_block) {
3337 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3338 				 "Block bitmap for group %u overlaps "
3339 				 "superblock", i);
3340 			if (!sb_rdonly(sb))
3341 				return 0;
3342 		}
3343 		if (block_bitmap >= sb_block + 1 &&
3344 		    block_bitmap <= last_bg_block) {
3345 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3346 				 "Block bitmap for group %u overlaps "
3347 				 "block group descriptors", i);
3348 			if (!sb_rdonly(sb))
3349 				return 0;
3350 		}
3351 		if (block_bitmap < first_block || block_bitmap > last_block) {
3352 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3353 			       "Block bitmap for group %u not in group "
3354 			       "(block %llu)!", i, block_bitmap);
3355 			return 0;
3356 		}
3357 		inode_bitmap = ext4_inode_bitmap(sb, gdp);
3358 		if (inode_bitmap == sb_block) {
3359 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3360 				 "Inode bitmap for group %u overlaps "
3361 				 "superblock", i);
3362 			if (!sb_rdonly(sb))
3363 				return 0;
3364 		}
3365 		if (inode_bitmap >= sb_block + 1 &&
3366 		    inode_bitmap <= last_bg_block) {
3367 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3368 				 "Inode bitmap for group %u overlaps "
3369 				 "block group descriptors", i);
3370 			if (!sb_rdonly(sb))
3371 				return 0;
3372 		}
3373 		if (inode_bitmap < first_block || inode_bitmap > last_block) {
3374 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3375 			       "Inode bitmap for group %u not in group "
3376 			       "(block %llu)!", i, inode_bitmap);
3377 			return 0;
3378 		}
3379 		inode_table = ext4_inode_table(sb, gdp);
3380 		if (inode_table == sb_block) {
3381 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3382 				 "Inode table for group %u overlaps "
3383 				 "superblock", i);
3384 			if (!sb_rdonly(sb))
3385 				return 0;
3386 		}
3387 		if (inode_table >= sb_block + 1 &&
3388 		    inode_table <= last_bg_block) {
3389 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3390 				 "Inode table for group %u overlaps "
3391 				 "block group descriptors", i);
3392 			if (!sb_rdonly(sb))
3393 				return 0;
3394 		}
3395 		if (inode_table < first_block ||
3396 		    inode_table + sbi->s_itb_per_group - 1 > last_block) {
3397 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3398 			       "Inode table for group %u not in group "
3399 			       "(block %llu)!", i, inode_table);
3400 			return 0;
3401 		}
3402 		ext4_lock_group(sb, i);
3403 		if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3404 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3405 				 "Checksum for group %u failed (%u!=%u)",
3406 				 i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3407 				     gdp)), le16_to_cpu(gdp->bg_checksum));
3408 			if (!sb_rdonly(sb)) {
3409 				ext4_unlock_group(sb, i);
3410 				return 0;
3411 			}
3412 		}
3413 		ext4_unlock_group(sb, i);
3414 		if (!flexbg_flag)
3415 			first_block += EXT4_BLOCKS_PER_GROUP(sb);
3416 	}
3417 	if (NULL != first_not_zeroed)
3418 		*first_not_zeroed = grp;
3419 	return 1;
3420 }
3421 
3422 /*
3423  * Maximal extent format file size.
3424  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3425  * extent format containers, within a sector_t, and within i_blocks
3426  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3427  * so that won't be a limiting factor.
3428  *
3429  * However there is other limiting factor. We do store extents in the form
3430  * of starting block and length, hence the resulting length of the extent
3431  * covering maximum file size must fit into on-disk format containers as
3432  * well. Given that length is always by 1 unit bigger than max unit (because
3433  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3434  *
3435  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3436  */
3437 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3438 {
3439 	loff_t res;
3440 	loff_t upper_limit = MAX_LFS_FILESIZE;
3441 
3442 	BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3443 
3444 	if (!has_huge_files) {
3445 		upper_limit = (1LL << 32) - 1;
3446 
3447 		/* total blocks in file system block size */
3448 		upper_limit >>= (blkbits - 9);
3449 		upper_limit <<= blkbits;
3450 	}
3451 
3452 	/*
3453 	 * 32-bit extent-start container, ee_block. We lower the maxbytes
3454 	 * by one fs block, so ee_len can cover the extent of maximum file
3455 	 * size
3456 	 */
3457 	res = (1LL << 32) - 1;
3458 	res <<= blkbits;
3459 
3460 	/* Sanity check against vm- & vfs- imposed limits */
3461 	if (res > upper_limit)
3462 		res = upper_limit;
3463 
3464 	return res;
3465 }
3466 
3467 /*
3468  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3469  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3470  * We need to be 1 filesystem block less than the 2^48 sector limit.
3471  */
3472 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3473 {
3474 	unsigned long long upper_limit, res = EXT4_NDIR_BLOCKS;
3475 	int meta_blocks;
3476 
3477 	/*
3478 	 * This is calculated to be the largest file size for a dense, block
3479 	 * mapped file such that the file's total number of 512-byte sectors,
3480 	 * including data and all indirect blocks, does not exceed (2^48 - 1).
3481 	 *
3482 	 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3483 	 * number of 512-byte sectors of the file.
3484 	 */
3485 	if (!has_huge_files) {
3486 		/*
3487 		 * !has_huge_files or implies that the inode i_block field
3488 		 * represents total file blocks in 2^32 512-byte sectors ==
3489 		 * size of vfs inode i_blocks * 8
3490 		 */
3491 		upper_limit = (1LL << 32) - 1;
3492 
3493 		/* total blocks in file system block size */
3494 		upper_limit >>= (bits - 9);
3495 
3496 	} else {
3497 		/*
3498 		 * We use 48 bit ext4_inode i_blocks
3499 		 * With EXT4_HUGE_FILE_FL set the i_blocks
3500 		 * represent total number of blocks in
3501 		 * file system block size
3502 		 */
3503 		upper_limit = (1LL << 48) - 1;
3504 
3505 	}
3506 
3507 	/* indirect blocks */
3508 	meta_blocks = 1;
3509 	/* double indirect blocks */
3510 	meta_blocks += 1 + (1LL << (bits-2));
3511 	/* tripple indirect blocks */
3512 	meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3513 
3514 	upper_limit -= meta_blocks;
3515 	upper_limit <<= bits;
3516 
3517 	res += 1LL << (bits-2);
3518 	res += 1LL << (2*(bits-2));
3519 	res += 1LL << (3*(bits-2));
3520 	res <<= bits;
3521 	if (res > upper_limit)
3522 		res = upper_limit;
3523 
3524 	if (res > MAX_LFS_FILESIZE)
3525 		res = MAX_LFS_FILESIZE;
3526 
3527 	return (loff_t)res;
3528 }
3529 
3530 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3531 				   ext4_fsblk_t logical_sb_block, int nr)
3532 {
3533 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3534 	ext4_group_t bg, first_meta_bg;
3535 	int has_super = 0;
3536 
3537 	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3538 
3539 	if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3540 		return logical_sb_block + nr + 1;
3541 	bg = sbi->s_desc_per_block * nr;
3542 	if (ext4_bg_has_super(sb, bg))
3543 		has_super = 1;
3544 
3545 	/*
3546 	 * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3547 	 * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3548 	 * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3549 	 * compensate.
3550 	 */
3551 	if (sb->s_blocksize == 1024 && nr == 0 &&
3552 	    le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3553 		has_super++;
3554 
3555 	return (has_super + ext4_group_first_block_no(sb, bg));
3556 }
3557 
3558 /**
3559  * ext4_get_stripe_size: Get the stripe size.
3560  * @sbi: In memory super block info
3561  *
3562  * If we have specified it via mount option, then
3563  * use the mount option value. If the value specified at mount time is
3564  * greater than the blocks per group use the super block value.
3565  * If the super block value is greater than blocks per group return 0.
3566  * Allocator needs it be less than blocks per group.
3567  *
3568  */
3569 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3570 {
3571 	unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3572 	unsigned long stripe_width =
3573 			le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3574 	int ret;
3575 
3576 	if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3577 		ret = sbi->s_stripe;
3578 	else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3579 		ret = stripe_width;
3580 	else if (stride && stride <= sbi->s_blocks_per_group)
3581 		ret = stride;
3582 	else
3583 		ret = 0;
3584 
3585 	/*
3586 	 * If the stripe width is 1, this makes no sense and
3587 	 * we set it to 0 to turn off stripe handling code.
3588 	 */
3589 	if (ret <= 1)
3590 		ret = 0;
3591 
3592 	return ret;
3593 }
3594 
3595 /*
3596  * Check whether this filesystem can be mounted based on
3597  * the features present and the RDONLY/RDWR mount requested.
3598  * Returns 1 if this filesystem can be mounted as requested,
3599  * 0 if it cannot be.
3600  */
3601 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3602 {
3603 	if (ext4_has_unknown_ext4_incompat_features(sb)) {
3604 		ext4_msg(sb, KERN_ERR,
3605 			"Couldn't mount because of "
3606 			"unsupported optional features (%x)",
3607 			(le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3608 			~EXT4_FEATURE_INCOMPAT_SUPP));
3609 		return 0;
3610 	}
3611 
3612 #ifndef CONFIG_UNICODE
3613 	if (ext4_has_feature_casefold(sb)) {
3614 		ext4_msg(sb, KERN_ERR,
3615 			 "Filesystem with casefold feature cannot be "
3616 			 "mounted without CONFIG_UNICODE");
3617 		return 0;
3618 	}
3619 #endif
3620 
3621 	if (readonly)
3622 		return 1;
3623 
3624 	if (ext4_has_feature_readonly(sb)) {
3625 		ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3626 		sb->s_flags |= SB_RDONLY;
3627 		return 1;
3628 	}
3629 
3630 	/* Check that feature set is OK for a read-write mount */
3631 	if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3632 		ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3633 			 "unsupported optional features (%x)",
3634 			 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3635 				~EXT4_FEATURE_RO_COMPAT_SUPP));
3636 		return 0;
3637 	}
3638 	if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3639 		ext4_msg(sb, KERN_ERR,
3640 			 "Can't support bigalloc feature without "
3641 			 "extents feature\n");
3642 		return 0;
3643 	}
3644 
3645 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3646 	if (!readonly && (ext4_has_feature_quota(sb) ||
3647 			  ext4_has_feature_project(sb))) {
3648 		ext4_msg(sb, KERN_ERR,
3649 			 "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3650 		return 0;
3651 	}
3652 #endif  /* CONFIG_QUOTA */
3653 	return 1;
3654 }
3655 
3656 /*
3657  * This function is called once a day if we have errors logged
3658  * on the file system
3659  */
3660 static void print_daily_error_info(struct timer_list *t)
3661 {
3662 	struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3663 	struct super_block *sb = sbi->s_sb;
3664 	struct ext4_super_block *es = sbi->s_es;
3665 
3666 	if (es->s_error_count)
3667 		/* fsck newer than v1.41.13 is needed to clean this condition. */
3668 		ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3669 			 le32_to_cpu(es->s_error_count));
3670 	if (es->s_first_error_time) {
3671 		printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3672 		       sb->s_id,
3673 		       ext4_get_tstamp(es, s_first_error_time),
3674 		       (int) sizeof(es->s_first_error_func),
3675 		       es->s_first_error_func,
3676 		       le32_to_cpu(es->s_first_error_line));
3677 		if (es->s_first_error_ino)
3678 			printk(KERN_CONT ": inode %u",
3679 			       le32_to_cpu(es->s_first_error_ino));
3680 		if (es->s_first_error_block)
3681 			printk(KERN_CONT ": block %llu", (unsigned long long)
3682 			       le64_to_cpu(es->s_first_error_block));
3683 		printk(KERN_CONT "\n");
3684 	}
3685 	if (es->s_last_error_time) {
3686 		printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3687 		       sb->s_id,
3688 		       ext4_get_tstamp(es, s_last_error_time),
3689 		       (int) sizeof(es->s_last_error_func),
3690 		       es->s_last_error_func,
3691 		       le32_to_cpu(es->s_last_error_line));
3692 		if (es->s_last_error_ino)
3693 			printk(KERN_CONT ": inode %u",
3694 			       le32_to_cpu(es->s_last_error_ino));
3695 		if (es->s_last_error_block)
3696 			printk(KERN_CONT ": block %llu", (unsigned long long)
3697 			       le64_to_cpu(es->s_last_error_block));
3698 		printk(KERN_CONT "\n");
3699 	}
3700 	mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3701 }
3702 
3703 /* Find next suitable group and run ext4_init_inode_table */
3704 static int ext4_run_li_request(struct ext4_li_request *elr)
3705 {
3706 	struct ext4_group_desc *gdp = NULL;
3707 	struct super_block *sb = elr->lr_super;
3708 	ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3709 	ext4_group_t group = elr->lr_next_group;
3710 	unsigned int prefetch_ios = 0;
3711 	int ret = 0;
3712 	u64 start_time;
3713 
3714 	if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3715 		elr->lr_next_group = ext4_mb_prefetch(sb, group,
3716 				EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3717 		if (prefetch_ios)
3718 			ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3719 					      prefetch_ios);
3720 		trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3721 					    prefetch_ios);
3722 		if (group >= elr->lr_next_group) {
3723 			ret = 1;
3724 			if (elr->lr_first_not_zeroed != ngroups &&
3725 			    !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3726 				elr->lr_next_group = elr->lr_first_not_zeroed;
3727 				elr->lr_mode = EXT4_LI_MODE_ITABLE;
3728 				ret = 0;
3729 			}
3730 		}
3731 		return ret;
3732 	}
3733 
3734 	for (; group < ngroups; group++) {
3735 		gdp = ext4_get_group_desc(sb, group, NULL);
3736 		if (!gdp) {
3737 			ret = 1;
3738 			break;
3739 		}
3740 
3741 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3742 			break;
3743 	}
3744 
3745 	if (group >= ngroups)
3746 		ret = 1;
3747 
3748 	if (!ret) {
3749 		start_time = ktime_get_real_ns();
3750 		ret = ext4_init_inode_table(sb, group,
3751 					    elr->lr_timeout ? 0 : 1);
3752 		trace_ext4_lazy_itable_init(sb, group);
3753 		if (elr->lr_timeout == 0) {
3754 			elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3755 				EXT4_SB(elr->lr_super)->s_li_wait_mult);
3756 		}
3757 		elr->lr_next_sched = jiffies + elr->lr_timeout;
3758 		elr->lr_next_group = group + 1;
3759 	}
3760 	return ret;
3761 }
3762 
3763 /*
3764  * Remove lr_request from the list_request and free the
3765  * request structure. Should be called with li_list_mtx held
3766  */
3767 static void ext4_remove_li_request(struct ext4_li_request *elr)
3768 {
3769 	if (!elr)
3770 		return;
3771 
3772 	list_del(&elr->lr_request);
3773 	EXT4_SB(elr->lr_super)->s_li_request = NULL;
3774 	kfree(elr);
3775 }
3776 
3777 static void ext4_unregister_li_request(struct super_block *sb)
3778 {
3779 	mutex_lock(&ext4_li_mtx);
3780 	if (!ext4_li_info) {
3781 		mutex_unlock(&ext4_li_mtx);
3782 		return;
3783 	}
3784 
3785 	mutex_lock(&ext4_li_info->li_list_mtx);
3786 	ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3787 	mutex_unlock(&ext4_li_info->li_list_mtx);
3788 	mutex_unlock(&ext4_li_mtx);
3789 }
3790 
3791 static struct task_struct *ext4_lazyinit_task;
3792 
3793 /*
3794  * This is the function where ext4lazyinit thread lives. It walks
3795  * through the request list searching for next scheduled filesystem.
3796  * When such a fs is found, run the lazy initialization request
3797  * (ext4_rn_li_request) and keep track of the time spend in this
3798  * function. Based on that time we compute next schedule time of
3799  * the request. When walking through the list is complete, compute
3800  * next waking time and put itself into sleep.
3801  */
3802 static int ext4_lazyinit_thread(void *arg)
3803 {
3804 	struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3805 	struct list_head *pos, *n;
3806 	struct ext4_li_request *elr;
3807 	unsigned long next_wakeup, cur;
3808 
3809 	BUG_ON(NULL == eli);
3810 
3811 cont_thread:
3812 	while (true) {
3813 		next_wakeup = MAX_JIFFY_OFFSET;
3814 
3815 		mutex_lock(&eli->li_list_mtx);
3816 		if (list_empty(&eli->li_request_list)) {
3817 			mutex_unlock(&eli->li_list_mtx);
3818 			goto exit_thread;
3819 		}
3820 		list_for_each_safe(pos, n, &eli->li_request_list) {
3821 			int err = 0;
3822 			int progress = 0;
3823 			elr = list_entry(pos, struct ext4_li_request,
3824 					 lr_request);
3825 
3826 			if (time_before(jiffies, elr->lr_next_sched)) {
3827 				if (time_before(elr->lr_next_sched, next_wakeup))
3828 					next_wakeup = elr->lr_next_sched;
3829 				continue;
3830 			}
3831 			if (down_read_trylock(&elr->lr_super->s_umount)) {
3832 				if (sb_start_write_trylock(elr->lr_super)) {
3833 					progress = 1;
3834 					/*
3835 					 * We hold sb->s_umount, sb can not
3836 					 * be removed from the list, it is
3837 					 * now safe to drop li_list_mtx
3838 					 */
3839 					mutex_unlock(&eli->li_list_mtx);
3840 					err = ext4_run_li_request(elr);
3841 					sb_end_write(elr->lr_super);
3842 					mutex_lock(&eli->li_list_mtx);
3843 					n = pos->next;
3844 				}
3845 				up_read((&elr->lr_super->s_umount));
3846 			}
3847 			/* error, remove the lazy_init job */
3848 			if (err) {
3849 				ext4_remove_li_request(elr);
3850 				continue;
3851 			}
3852 			if (!progress) {
3853 				elr->lr_next_sched = jiffies +
3854 					(prandom_u32()
3855 					 % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3856 			}
3857 			if (time_before(elr->lr_next_sched, next_wakeup))
3858 				next_wakeup = elr->lr_next_sched;
3859 		}
3860 		mutex_unlock(&eli->li_list_mtx);
3861 
3862 		try_to_freeze();
3863 
3864 		cur = jiffies;
3865 		if ((time_after_eq(cur, next_wakeup)) ||
3866 		    (MAX_JIFFY_OFFSET == next_wakeup)) {
3867 			cond_resched();
3868 			continue;
3869 		}
3870 
3871 		schedule_timeout_interruptible(next_wakeup - cur);
3872 
3873 		if (kthread_should_stop()) {
3874 			ext4_clear_request_list();
3875 			goto exit_thread;
3876 		}
3877 	}
3878 
3879 exit_thread:
3880 	/*
3881 	 * It looks like the request list is empty, but we need
3882 	 * to check it under the li_list_mtx lock, to prevent any
3883 	 * additions into it, and of course we should lock ext4_li_mtx
3884 	 * to atomically free the list and ext4_li_info, because at
3885 	 * this point another ext4 filesystem could be registering
3886 	 * new one.
3887 	 */
3888 	mutex_lock(&ext4_li_mtx);
3889 	mutex_lock(&eli->li_list_mtx);
3890 	if (!list_empty(&eli->li_request_list)) {
3891 		mutex_unlock(&eli->li_list_mtx);
3892 		mutex_unlock(&ext4_li_mtx);
3893 		goto cont_thread;
3894 	}
3895 	mutex_unlock(&eli->li_list_mtx);
3896 	kfree(ext4_li_info);
3897 	ext4_li_info = NULL;
3898 	mutex_unlock(&ext4_li_mtx);
3899 
3900 	return 0;
3901 }
3902 
3903 static void ext4_clear_request_list(void)
3904 {
3905 	struct list_head *pos, *n;
3906 	struct ext4_li_request *elr;
3907 
3908 	mutex_lock(&ext4_li_info->li_list_mtx);
3909 	list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3910 		elr = list_entry(pos, struct ext4_li_request,
3911 				 lr_request);
3912 		ext4_remove_li_request(elr);
3913 	}
3914 	mutex_unlock(&ext4_li_info->li_list_mtx);
3915 }
3916 
3917 static int ext4_run_lazyinit_thread(void)
3918 {
3919 	ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3920 					 ext4_li_info, "ext4lazyinit");
3921 	if (IS_ERR(ext4_lazyinit_task)) {
3922 		int err = PTR_ERR(ext4_lazyinit_task);
3923 		ext4_clear_request_list();
3924 		kfree(ext4_li_info);
3925 		ext4_li_info = NULL;
3926 		printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3927 				 "initialization thread\n",
3928 				 err);
3929 		return err;
3930 	}
3931 	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3932 	return 0;
3933 }
3934 
3935 /*
3936  * Check whether it make sense to run itable init. thread or not.
3937  * If there is at least one uninitialized inode table, return
3938  * corresponding group number, else the loop goes through all
3939  * groups and return total number of groups.
3940  */
3941 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3942 {
3943 	ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3944 	struct ext4_group_desc *gdp = NULL;
3945 
3946 	if (!ext4_has_group_desc_csum(sb))
3947 		return ngroups;
3948 
3949 	for (group = 0; group < ngroups; group++) {
3950 		gdp = ext4_get_group_desc(sb, group, NULL);
3951 		if (!gdp)
3952 			continue;
3953 
3954 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3955 			break;
3956 	}
3957 
3958 	return group;
3959 }
3960 
3961 static int ext4_li_info_new(void)
3962 {
3963 	struct ext4_lazy_init *eli = NULL;
3964 
3965 	eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3966 	if (!eli)
3967 		return -ENOMEM;
3968 
3969 	INIT_LIST_HEAD(&eli->li_request_list);
3970 	mutex_init(&eli->li_list_mtx);
3971 
3972 	eli->li_state |= EXT4_LAZYINIT_QUIT;
3973 
3974 	ext4_li_info = eli;
3975 
3976 	return 0;
3977 }
3978 
3979 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3980 					    ext4_group_t start)
3981 {
3982 	struct ext4_li_request *elr;
3983 
3984 	elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3985 	if (!elr)
3986 		return NULL;
3987 
3988 	elr->lr_super = sb;
3989 	elr->lr_first_not_zeroed = start;
3990 	if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3991 		elr->lr_mode = EXT4_LI_MODE_ITABLE;
3992 		elr->lr_next_group = start;
3993 	} else {
3994 		elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3995 	}
3996 
3997 	/*
3998 	 * Randomize first schedule time of the request to
3999 	 * spread the inode table initialization requests
4000 	 * better.
4001 	 */
4002 	elr->lr_next_sched = jiffies + (prandom_u32() %
4003 				(EXT4_DEF_LI_MAX_START_DELAY * HZ));
4004 	return elr;
4005 }
4006 
4007 int ext4_register_li_request(struct super_block *sb,
4008 			     ext4_group_t first_not_zeroed)
4009 {
4010 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4011 	struct ext4_li_request *elr = NULL;
4012 	ext4_group_t ngroups = sbi->s_groups_count;
4013 	int ret = 0;
4014 
4015 	mutex_lock(&ext4_li_mtx);
4016 	if (sbi->s_li_request != NULL) {
4017 		/*
4018 		 * Reset timeout so it can be computed again, because
4019 		 * s_li_wait_mult might have changed.
4020 		 */
4021 		sbi->s_li_request->lr_timeout = 0;
4022 		goto out;
4023 	}
4024 
4025 	if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4026 	    (first_not_zeroed == ngroups || sb_rdonly(sb) ||
4027 	     !test_opt(sb, INIT_INODE_TABLE)))
4028 		goto out;
4029 
4030 	elr = ext4_li_request_new(sb, first_not_zeroed);
4031 	if (!elr) {
4032 		ret = -ENOMEM;
4033 		goto out;
4034 	}
4035 
4036 	if (NULL == ext4_li_info) {
4037 		ret = ext4_li_info_new();
4038 		if (ret)
4039 			goto out;
4040 	}
4041 
4042 	mutex_lock(&ext4_li_info->li_list_mtx);
4043 	list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4044 	mutex_unlock(&ext4_li_info->li_list_mtx);
4045 
4046 	sbi->s_li_request = elr;
4047 	/*
4048 	 * set elr to NULL here since it has been inserted to
4049 	 * the request_list and the removal and free of it is
4050 	 * handled by ext4_clear_request_list from now on.
4051 	 */
4052 	elr = NULL;
4053 
4054 	if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4055 		ret = ext4_run_lazyinit_thread();
4056 		if (ret)
4057 			goto out;
4058 	}
4059 out:
4060 	mutex_unlock(&ext4_li_mtx);
4061 	if (ret)
4062 		kfree(elr);
4063 	return ret;
4064 }
4065 
4066 /*
4067  * We do not need to lock anything since this is called on
4068  * module unload.
4069  */
4070 static void ext4_destroy_lazyinit_thread(void)
4071 {
4072 	/*
4073 	 * If thread exited earlier
4074 	 * there's nothing to be done.
4075 	 */
4076 	if (!ext4_li_info || !ext4_lazyinit_task)
4077 		return;
4078 
4079 	kthread_stop(ext4_lazyinit_task);
4080 }
4081 
4082 static int set_journal_csum_feature_set(struct super_block *sb)
4083 {
4084 	int ret = 1;
4085 	int compat, incompat;
4086 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4087 
4088 	if (ext4_has_metadata_csum(sb)) {
4089 		/* journal checksum v3 */
4090 		compat = 0;
4091 		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4092 	} else {
4093 		/* journal checksum v1 */
4094 		compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4095 		incompat = 0;
4096 	}
4097 
4098 	jbd2_journal_clear_features(sbi->s_journal,
4099 			JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4100 			JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4101 			JBD2_FEATURE_INCOMPAT_CSUM_V2);
4102 	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4103 		ret = jbd2_journal_set_features(sbi->s_journal,
4104 				compat, 0,
4105 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4106 				incompat);
4107 	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4108 		ret = jbd2_journal_set_features(sbi->s_journal,
4109 				compat, 0,
4110 				incompat);
4111 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4112 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4113 	} else {
4114 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4115 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4116 	}
4117 
4118 	return ret;
4119 }
4120 
4121 /*
4122  * Note: calculating the overhead so we can be compatible with
4123  * historical BSD practice is quite difficult in the face of
4124  * clusters/bigalloc.  This is because multiple metadata blocks from
4125  * different block group can end up in the same allocation cluster.
4126  * Calculating the exact overhead in the face of clustered allocation
4127  * requires either O(all block bitmaps) in memory or O(number of block
4128  * groups**2) in time.  We will still calculate the superblock for
4129  * older file systems --- and if we come across with a bigalloc file
4130  * system with zero in s_overhead_clusters the estimate will be close to
4131  * correct especially for very large cluster sizes --- but for newer
4132  * file systems, it's better to calculate this figure once at mkfs
4133  * time, and store it in the superblock.  If the superblock value is
4134  * present (even for non-bigalloc file systems), we will use it.
4135  */
4136 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4137 			  char *buf)
4138 {
4139 	struct ext4_sb_info	*sbi = EXT4_SB(sb);
4140 	struct ext4_group_desc	*gdp;
4141 	ext4_fsblk_t		first_block, last_block, b;
4142 	ext4_group_t		i, ngroups = ext4_get_groups_count(sb);
4143 	int			s, j, count = 0;
4144 
4145 	if (!ext4_has_feature_bigalloc(sb))
4146 		return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
4147 			sbi->s_itb_per_group + 2);
4148 
4149 	first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4150 		(grp * EXT4_BLOCKS_PER_GROUP(sb));
4151 	last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4152 	for (i = 0; i < ngroups; i++) {
4153 		gdp = ext4_get_group_desc(sb, i, NULL);
4154 		b = ext4_block_bitmap(sb, gdp);
4155 		if (b >= first_block && b <= last_block) {
4156 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4157 			count++;
4158 		}
4159 		b = ext4_inode_bitmap(sb, gdp);
4160 		if (b >= first_block && b <= last_block) {
4161 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4162 			count++;
4163 		}
4164 		b = ext4_inode_table(sb, gdp);
4165 		if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4166 			for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4167 				int c = EXT4_B2C(sbi, b - first_block);
4168 				ext4_set_bit(c, buf);
4169 				count++;
4170 			}
4171 		if (i != grp)
4172 			continue;
4173 		s = 0;
4174 		if (ext4_bg_has_super(sb, grp)) {
4175 			ext4_set_bit(s++, buf);
4176 			count++;
4177 		}
4178 		j = ext4_bg_num_gdb(sb, grp);
4179 		if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4180 			ext4_error(sb, "Invalid number of block group "
4181 				   "descriptor blocks: %d", j);
4182 			j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4183 		}
4184 		count += j;
4185 		for (; j > 0; j--)
4186 			ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4187 	}
4188 	if (!count)
4189 		return 0;
4190 	return EXT4_CLUSTERS_PER_GROUP(sb) -
4191 		ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4192 }
4193 
4194 /*
4195  * Compute the overhead and stash it in sbi->s_overhead
4196  */
4197 int ext4_calculate_overhead(struct super_block *sb)
4198 {
4199 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4200 	struct ext4_super_block *es = sbi->s_es;
4201 	struct inode *j_inode;
4202 	unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4203 	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4204 	ext4_fsblk_t overhead = 0;
4205 	char *buf = (char *) get_zeroed_page(GFP_NOFS);
4206 
4207 	if (!buf)
4208 		return -ENOMEM;
4209 
4210 	/*
4211 	 * Compute the overhead (FS structures).  This is constant
4212 	 * for a given filesystem unless the number of block groups
4213 	 * changes so we cache the previous value until it does.
4214 	 */
4215 
4216 	/*
4217 	 * All of the blocks before first_data_block are overhead
4218 	 */
4219 	overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4220 
4221 	/*
4222 	 * Add the overhead found in each block group
4223 	 */
4224 	for (i = 0; i < ngroups; i++) {
4225 		int blks;
4226 
4227 		blks = count_overhead(sb, i, buf);
4228 		overhead += blks;
4229 		if (blks)
4230 			memset(buf, 0, PAGE_SIZE);
4231 		cond_resched();
4232 	}
4233 
4234 	/*
4235 	 * Add the internal journal blocks whether the journal has been
4236 	 * loaded or not
4237 	 */
4238 	if (sbi->s_journal && !sbi->s_journal_bdev)
4239 		overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4240 	else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4241 		/* j_inum for internal journal is non-zero */
4242 		j_inode = ext4_get_journal_inode(sb, j_inum);
4243 		if (j_inode) {
4244 			j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4245 			overhead += EXT4_NUM_B2C(sbi, j_blocks);
4246 			iput(j_inode);
4247 		} else {
4248 			ext4_msg(sb, KERN_ERR, "can't get journal size");
4249 		}
4250 	}
4251 	sbi->s_overhead = overhead;
4252 	smp_wmb();
4253 	free_page((unsigned long) buf);
4254 	return 0;
4255 }
4256 
4257 static void ext4_set_resv_clusters(struct super_block *sb)
4258 {
4259 	ext4_fsblk_t resv_clusters;
4260 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4261 
4262 	/*
4263 	 * There's no need to reserve anything when we aren't using extents.
4264 	 * The space estimates are exact, there are no unwritten extents,
4265 	 * hole punching doesn't need new metadata... This is needed especially
4266 	 * to keep ext2/3 backward compatibility.
4267 	 */
4268 	if (!ext4_has_feature_extents(sb))
4269 		return;
4270 	/*
4271 	 * By default we reserve 2% or 4096 clusters, whichever is smaller.
4272 	 * This should cover the situations where we can not afford to run
4273 	 * out of space like for example punch hole, or converting
4274 	 * unwritten extents in delalloc path. In most cases such
4275 	 * allocation would require 1, or 2 blocks, higher numbers are
4276 	 * very rare.
4277 	 */
4278 	resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4279 			 sbi->s_cluster_bits);
4280 
4281 	do_div(resv_clusters, 50);
4282 	resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4283 
4284 	atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4285 }
4286 
4287 static const char *ext4_quota_mode(struct super_block *sb)
4288 {
4289 #ifdef CONFIG_QUOTA
4290 	if (!ext4_quota_capable(sb))
4291 		return "none";
4292 
4293 	if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4294 		return "journalled";
4295 	else
4296 		return "writeback";
4297 #else
4298 	return "disabled";
4299 #endif
4300 }
4301 
4302 static void ext4_setup_csum_trigger(struct super_block *sb,
4303 				    enum ext4_journal_trigger_type type,
4304 				    void (*trigger)(
4305 					struct jbd2_buffer_trigger_type *type,
4306 					struct buffer_head *bh,
4307 					void *mapped_data,
4308 					size_t size))
4309 {
4310 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4311 
4312 	sbi->s_journal_triggers[type].sb = sb;
4313 	sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4314 }
4315 
4316 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4317 {
4318 	if (!sbi)
4319 		return;
4320 
4321 	kfree(sbi->s_blockgroup_lock);
4322 	fs_put_dax(sbi->s_daxdev);
4323 	kfree(sbi);
4324 }
4325 
4326 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4327 {
4328 	struct ext4_sb_info *sbi;
4329 
4330 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4331 	if (!sbi)
4332 		return NULL;
4333 
4334 	sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off);
4335 
4336 	sbi->s_blockgroup_lock =
4337 		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4338 
4339 	if (!sbi->s_blockgroup_lock)
4340 		goto err_out;
4341 
4342 	sb->s_fs_info = sbi;
4343 	sbi->s_sb = sb;
4344 	return sbi;
4345 err_out:
4346 	fs_put_dax(sbi->s_daxdev);
4347 	kfree(sbi);
4348 	return NULL;
4349 }
4350 
4351 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
4352 {
4353 	struct buffer_head *bh, **group_desc;
4354 	struct ext4_super_block *es = NULL;
4355 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4356 	struct flex_groups **flex_groups;
4357 	ext4_fsblk_t block;
4358 	ext4_fsblk_t logical_sb_block;
4359 	unsigned long offset = 0;
4360 	unsigned long def_mount_opts;
4361 	struct inode *root;
4362 	int ret = -ENOMEM;
4363 	int blocksize, clustersize;
4364 	unsigned int db_count;
4365 	unsigned int i;
4366 	int needs_recovery, has_huge_files;
4367 	__u64 blocks_count;
4368 	int err = 0;
4369 	ext4_group_t first_not_zeroed;
4370 	struct ext4_fs_context *ctx = fc->fs_private;
4371 	int silent = fc->sb_flags & SB_SILENT;
4372 
4373 	/* Set defaults for the variables that will be set during parsing */
4374 	ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4375 	ctx->mb_optimize_scan = DEFAULT_MB_OPTIMIZE_SCAN;
4376 
4377 	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4378 	sbi->s_sectors_written_start =
4379 		part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
4380 
4381 	/* -EINVAL is default */
4382 	ret = -EINVAL;
4383 	blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4384 	if (!blocksize) {
4385 		ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4386 		goto out_fail;
4387 	}
4388 
4389 	/*
4390 	 * The ext4 superblock will not be buffer aligned for other than 1kB
4391 	 * block sizes.  We need to calculate the offset from buffer start.
4392 	 */
4393 	if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4394 		logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4395 		offset = do_div(logical_sb_block, blocksize);
4396 	} else {
4397 		logical_sb_block = sbi->s_sb_block;
4398 	}
4399 
4400 	bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4401 	if (IS_ERR(bh)) {
4402 		ext4_msg(sb, KERN_ERR, "unable to read superblock");
4403 		ret = PTR_ERR(bh);
4404 		goto out_fail;
4405 	}
4406 	/*
4407 	 * Note: s_es must be initialized as soon as possible because
4408 	 *       some ext4 macro-instructions depend on its value
4409 	 */
4410 	es = (struct ext4_super_block *) (bh->b_data + offset);
4411 	sbi->s_es = es;
4412 	sb->s_magic = le16_to_cpu(es->s_magic);
4413 	if (sb->s_magic != EXT4_SUPER_MAGIC)
4414 		goto cantfind_ext4;
4415 	sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4416 
4417 	/* Warn if metadata_csum and gdt_csum are both set. */
4418 	if (ext4_has_feature_metadata_csum(sb) &&
4419 	    ext4_has_feature_gdt_csum(sb))
4420 		ext4_warning(sb, "metadata_csum and uninit_bg are "
4421 			     "redundant flags; please run fsck.");
4422 
4423 	/* Check for a known checksum algorithm */
4424 	if (!ext4_verify_csum_type(sb, es)) {
4425 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4426 			 "unknown checksum algorithm.");
4427 		silent = 1;
4428 		goto cantfind_ext4;
4429 	}
4430 	ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4431 				ext4_orphan_file_block_trigger);
4432 
4433 	/* Load the checksum driver */
4434 	sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4435 	if (IS_ERR(sbi->s_chksum_driver)) {
4436 		ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4437 		ret = PTR_ERR(sbi->s_chksum_driver);
4438 		sbi->s_chksum_driver = NULL;
4439 		goto failed_mount;
4440 	}
4441 
4442 	/* Check superblock checksum */
4443 	if (!ext4_superblock_csum_verify(sb, es)) {
4444 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4445 			 "invalid superblock checksum.  Run e2fsck?");
4446 		silent = 1;
4447 		ret = -EFSBADCRC;
4448 		goto cantfind_ext4;
4449 	}
4450 
4451 	/* Precompute checksum seed for all metadata */
4452 	if (ext4_has_feature_csum_seed(sb))
4453 		sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4454 	else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4455 		sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4456 					       sizeof(es->s_uuid));
4457 
4458 	/* Set defaults before we parse the mount options */
4459 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4460 	set_opt(sb, INIT_INODE_TABLE);
4461 	if (def_mount_opts & EXT4_DEFM_DEBUG)
4462 		set_opt(sb, DEBUG);
4463 	if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4464 		set_opt(sb, GRPID);
4465 	if (def_mount_opts & EXT4_DEFM_UID16)
4466 		set_opt(sb, NO_UID32);
4467 	/* xattr user namespace & acls are now defaulted on */
4468 	set_opt(sb, XATTR_USER);
4469 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4470 	set_opt(sb, POSIX_ACL);
4471 #endif
4472 	if (ext4_has_feature_fast_commit(sb))
4473 		set_opt2(sb, JOURNAL_FAST_COMMIT);
4474 	/* don't forget to enable journal_csum when metadata_csum is enabled. */
4475 	if (ext4_has_metadata_csum(sb))
4476 		set_opt(sb, JOURNAL_CHECKSUM);
4477 
4478 	if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4479 		set_opt(sb, JOURNAL_DATA);
4480 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4481 		set_opt(sb, ORDERED_DATA);
4482 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4483 		set_opt(sb, WRITEBACK_DATA);
4484 
4485 	if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4486 		set_opt(sb, ERRORS_PANIC);
4487 	else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4488 		set_opt(sb, ERRORS_CONT);
4489 	else
4490 		set_opt(sb, ERRORS_RO);
4491 	/* block_validity enabled by default; disable with noblock_validity */
4492 	set_opt(sb, BLOCK_VALIDITY);
4493 	if (def_mount_opts & EXT4_DEFM_DISCARD)
4494 		set_opt(sb, DISCARD);
4495 
4496 	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4497 	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4498 	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4499 	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4500 	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4501 
4502 	if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4503 		set_opt(sb, BARRIER);
4504 
4505 	/*
4506 	 * enable delayed allocation by default
4507 	 * Use -o nodelalloc to turn it off
4508 	 */
4509 	if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4510 	    ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4511 		set_opt(sb, DELALLOC);
4512 
4513 	/*
4514 	 * set default s_li_wait_mult for lazyinit, for the case there is
4515 	 * no mount option specified.
4516 	 */
4517 	sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4518 
4519 	if (le32_to_cpu(es->s_log_block_size) >
4520 	    (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4521 		ext4_msg(sb, KERN_ERR,
4522 			 "Invalid log block size: %u",
4523 			 le32_to_cpu(es->s_log_block_size));
4524 		goto failed_mount;
4525 	}
4526 	if (le32_to_cpu(es->s_log_cluster_size) >
4527 	    (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4528 		ext4_msg(sb, KERN_ERR,
4529 			 "Invalid log cluster size: %u",
4530 			 le32_to_cpu(es->s_log_cluster_size));
4531 		goto failed_mount;
4532 	}
4533 
4534 	blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4535 
4536 	if (blocksize == PAGE_SIZE)
4537 		set_opt(sb, DIOREAD_NOLOCK);
4538 
4539 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4540 		sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4541 		sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4542 	} else {
4543 		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4544 		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4545 		if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4546 			ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4547 				 sbi->s_first_ino);
4548 			goto failed_mount;
4549 		}
4550 		if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4551 		    (!is_power_of_2(sbi->s_inode_size)) ||
4552 		    (sbi->s_inode_size > blocksize)) {
4553 			ext4_msg(sb, KERN_ERR,
4554 			       "unsupported inode size: %d",
4555 			       sbi->s_inode_size);
4556 			ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4557 			goto failed_mount;
4558 		}
4559 		/*
4560 		 * i_atime_extra is the last extra field available for
4561 		 * [acm]times in struct ext4_inode. Checking for that
4562 		 * field should suffice to ensure we have extra space
4563 		 * for all three.
4564 		 */
4565 		if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4566 			sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4567 			sb->s_time_gran = 1;
4568 			sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4569 		} else {
4570 			sb->s_time_gran = NSEC_PER_SEC;
4571 			sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4572 		}
4573 		sb->s_time_min = EXT4_TIMESTAMP_MIN;
4574 	}
4575 	if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4576 		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4577 			EXT4_GOOD_OLD_INODE_SIZE;
4578 		if (ext4_has_feature_extra_isize(sb)) {
4579 			unsigned v, max = (sbi->s_inode_size -
4580 					   EXT4_GOOD_OLD_INODE_SIZE);
4581 
4582 			v = le16_to_cpu(es->s_want_extra_isize);
4583 			if (v > max) {
4584 				ext4_msg(sb, KERN_ERR,
4585 					 "bad s_want_extra_isize: %d", v);
4586 				goto failed_mount;
4587 			}
4588 			if (sbi->s_want_extra_isize < v)
4589 				sbi->s_want_extra_isize = v;
4590 
4591 			v = le16_to_cpu(es->s_min_extra_isize);
4592 			if (v > max) {
4593 				ext4_msg(sb, KERN_ERR,
4594 					 "bad s_min_extra_isize: %d", v);
4595 				goto failed_mount;
4596 			}
4597 			if (sbi->s_want_extra_isize < v)
4598 				sbi->s_want_extra_isize = v;
4599 		}
4600 	}
4601 
4602 	err = parse_apply_sb_mount_options(sb, ctx);
4603 	if (err < 0)
4604 		goto failed_mount;
4605 
4606 	sbi->s_def_mount_opt = sbi->s_mount_opt;
4607 
4608 	err = ext4_check_opt_consistency(fc, sb);
4609 	if (err < 0)
4610 		goto failed_mount;
4611 
4612 	err = ext4_apply_options(fc, sb);
4613 	if (err < 0)
4614 		goto failed_mount;
4615 
4616 #ifdef CONFIG_UNICODE
4617 	if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4618 		const struct ext4_sb_encodings *encoding_info;
4619 		struct unicode_map *encoding;
4620 		__u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4621 
4622 		encoding_info = ext4_sb_read_encoding(es);
4623 		if (!encoding_info) {
4624 			ext4_msg(sb, KERN_ERR,
4625 				 "Encoding requested by superblock is unknown");
4626 			goto failed_mount;
4627 		}
4628 
4629 		encoding = utf8_load(encoding_info->version);
4630 		if (IS_ERR(encoding)) {
4631 			ext4_msg(sb, KERN_ERR,
4632 				 "can't mount with superblock charset: %s-%u.%u.%u "
4633 				 "not supported by the kernel. flags: 0x%x.",
4634 				 encoding_info->name,
4635 				 unicode_major(encoding_info->version),
4636 				 unicode_minor(encoding_info->version),
4637 				 unicode_rev(encoding_info->version),
4638 				 encoding_flags);
4639 			goto failed_mount;
4640 		}
4641 		ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4642 			 "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4643 			 unicode_major(encoding_info->version),
4644 			 unicode_minor(encoding_info->version),
4645 			 unicode_rev(encoding_info->version),
4646 			 encoding_flags);
4647 
4648 		sb->s_encoding = encoding;
4649 		sb->s_encoding_flags = encoding_flags;
4650 	}
4651 #endif
4652 
4653 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4654 		printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4655 		/* can't mount with both data=journal and dioread_nolock. */
4656 		clear_opt(sb, DIOREAD_NOLOCK);
4657 		clear_opt2(sb, JOURNAL_FAST_COMMIT);
4658 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4659 			ext4_msg(sb, KERN_ERR, "can't mount with "
4660 				 "both data=journal and delalloc");
4661 			goto failed_mount;
4662 		}
4663 		if (test_opt(sb, DAX_ALWAYS)) {
4664 			ext4_msg(sb, KERN_ERR, "can't mount with "
4665 				 "both data=journal and dax");
4666 			goto failed_mount;
4667 		}
4668 		if (ext4_has_feature_encrypt(sb)) {
4669 			ext4_msg(sb, KERN_WARNING,
4670 				 "encrypted files will use data=ordered "
4671 				 "instead of data journaling mode");
4672 		}
4673 		if (test_opt(sb, DELALLOC))
4674 			clear_opt(sb, DELALLOC);
4675 	} else {
4676 		sb->s_iflags |= SB_I_CGROUPWB;
4677 	}
4678 
4679 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4680 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4681 
4682 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4683 	    (ext4_has_compat_features(sb) ||
4684 	     ext4_has_ro_compat_features(sb) ||
4685 	     ext4_has_incompat_features(sb)))
4686 		ext4_msg(sb, KERN_WARNING,
4687 		       "feature flags set on rev 0 fs, "
4688 		       "running e2fsck is recommended");
4689 
4690 	if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4691 		set_opt2(sb, HURD_COMPAT);
4692 		if (ext4_has_feature_64bit(sb)) {
4693 			ext4_msg(sb, KERN_ERR,
4694 				 "The Hurd can't support 64-bit file systems");
4695 			goto failed_mount;
4696 		}
4697 
4698 		/*
4699 		 * ea_inode feature uses l_i_version field which is not
4700 		 * available in HURD_COMPAT mode.
4701 		 */
4702 		if (ext4_has_feature_ea_inode(sb)) {
4703 			ext4_msg(sb, KERN_ERR,
4704 				 "ea_inode feature is not supported for Hurd");
4705 			goto failed_mount;
4706 		}
4707 	}
4708 
4709 	if (IS_EXT2_SB(sb)) {
4710 		if (ext2_feature_set_ok(sb))
4711 			ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4712 				 "using the ext4 subsystem");
4713 		else {
4714 			/*
4715 			 * If we're probing be silent, if this looks like
4716 			 * it's actually an ext[34] filesystem.
4717 			 */
4718 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4719 				goto failed_mount;
4720 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4721 				 "to feature incompatibilities");
4722 			goto failed_mount;
4723 		}
4724 	}
4725 
4726 	if (IS_EXT3_SB(sb)) {
4727 		if (ext3_feature_set_ok(sb))
4728 			ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4729 				 "using the ext4 subsystem");
4730 		else {
4731 			/*
4732 			 * If we're probing be silent, if this looks like
4733 			 * it's actually an ext4 filesystem.
4734 			 */
4735 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4736 				goto failed_mount;
4737 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4738 				 "to feature incompatibilities");
4739 			goto failed_mount;
4740 		}
4741 	}
4742 
4743 	/*
4744 	 * Check feature flags regardless of the revision level, since we
4745 	 * previously didn't change the revision level when setting the flags,
4746 	 * so there is a chance incompat flags are set on a rev 0 filesystem.
4747 	 */
4748 	if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4749 		goto failed_mount;
4750 
4751 	if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4752 		ext4_msg(sb, KERN_ERR,
4753 			 "Number of reserved GDT blocks insanely large: %d",
4754 			 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4755 		goto failed_mount;
4756 	}
4757 
4758 	if (sbi->s_daxdev) {
4759 		if (blocksize == PAGE_SIZE)
4760 			set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4761 		else
4762 			ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4763 	}
4764 
4765 	if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4766 		if (ext4_has_feature_inline_data(sb)) {
4767 			ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4768 					" that may contain inline data");
4769 			goto failed_mount;
4770 		}
4771 		if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4772 			ext4_msg(sb, KERN_ERR,
4773 				"DAX unsupported by block device.");
4774 			goto failed_mount;
4775 		}
4776 	}
4777 
4778 	if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4779 		ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4780 			 es->s_encryption_level);
4781 		goto failed_mount;
4782 	}
4783 
4784 	if (sb->s_blocksize != blocksize) {
4785 		/*
4786 		 * bh must be released before kill_bdev(), otherwise
4787 		 * it won't be freed and its page also. kill_bdev()
4788 		 * is called by sb_set_blocksize().
4789 		 */
4790 		brelse(bh);
4791 		/* Validate the filesystem blocksize */
4792 		if (!sb_set_blocksize(sb, blocksize)) {
4793 			ext4_msg(sb, KERN_ERR, "bad block size %d",
4794 					blocksize);
4795 			bh = NULL;
4796 			goto failed_mount;
4797 		}
4798 
4799 		logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4800 		offset = do_div(logical_sb_block, blocksize);
4801 		bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4802 		if (IS_ERR(bh)) {
4803 			ext4_msg(sb, KERN_ERR,
4804 			       "Can't read superblock on 2nd try");
4805 			ret = PTR_ERR(bh);
4806 			bh = NULL;
4807 			goto failed_mount;
4808 		}
4809 		es = (struct ext4_super_block *)(bh->b_data + offset);
4810 		sbi->s_es = es;
4811 		if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4812 			ext4_msg(sb, KERN_ERR,
4813 			       "Magic mismatch, very weird!");
4814 			goto failed_mount;
4815 		}
4816 	}
4817 
4818 	has_huge_files = ext4_has_feature_huge_file(sb);
4819 	sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4820 						      has_huge_files);
4821 	sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4822 
4823 	sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4824 	if (ext4_has_feature_64bit(sb)) {
4825 		if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4826 		    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4827 		    !is_power_of_2(sbi->s_desc_size)) {
4828 			ext4_msg(sb, KERN_ERR,
4829 			       "unsupported descriptor size %lu",
4830 			       sbi->s_desc_size);
4831 			goto failed_mount;
4832 		}
4833 	} else
4834 		sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4835 
4836 	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4837 	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4838 
4839 	sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4840 	if (sbi->s_inodes_per_block == 0)
4841 		goto cantfind_ext4;
4842 	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4843 	    sbi->s_inodes_per_group > blocksize * 8) {
4844 		ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4845 			 sbi->s_inodes_per_group);
4846 		goto failed_mount;
4847 	}
4848 	sbi->s_itb_per_group = sbi->s_inodes_per_group /
4849 					sbi->s_inodes_per_block;
4850 	sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4851 	sbi->s_sbh = bh;
4852 	sbi->s_mount_state = le16_to_cpu(es->s_state);
4853 	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4854 	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4855 
4856 	for (i = 0; i < 4; i++)
4857 		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4858 	sbi->s_def_hash_version = es->s_def_hash_version;
4859 	if (ext4_has_feature_dir_index(sb)) {
4860 		i = le32_to_cpu(es->s_flags);
4861 		if (i & EXT2_FLAGS_UNSIGNED_HASH)
4862 			sbi->s_hash_unsigned = 3;
4863 		else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4864 #ifdef __CHAR_UNSIGNED__
4865 			if (!sb_rdonly(sb))
4866 				es->s_flags |=
4867 					cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4868 			sbi->s_hash_unsigned = 3;
4869 #else
4870 			if (!sb_rdonly(sb))
4871 				es->s_flags |=
4872 					cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4873 #endif
4874 		}
4875 	}
4876 
4877 	/* Handle clustersize */
4878 	clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4879 	if (ext4_has_feature_bigalloc(sb)) {
4880 		if (clustersize < blocksize) {
4881 			ext4_msg(sb, KERN_ERR,
4882 				 "cluster size (%d) smaller than "
4883 				 "block size (%d)", clustersize, blocksize);
4884 			goto failed_mount;
4885 		}
4886 		sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4887 			le32_to_cpu(es->s_log_block_size);
4888 		sbi->s_clusters_per_group =
4889 			le32_to_cpu(es->s_clusters_per_group);
4890 		if (sbi->s_clusters_per_group > blocksize * 8) {
4891 			ext4_msg(sb, KERN_ERR,
4892 				 "#clusters per group too big: %lu",
4893 				 sbi->s_clusters_per_group);
4894 			goto failed_mount;
4895 		}
4896 		if (sbi->s_blocks_per_group !=
4897 		    (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4898 			ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4899 				 "clusters per group (%lu) inconsistent",
4900 				 sbi->s_blocks_per_group,
4901 				 sbi->s_clusters_per_group);
4902 			goto failed_mount;
4903 		}
4904 	} else {
4905 		if (clustersize != blocksize) {
4906 			ext4_msg(sb, KERN_ERR,
4907 				 "fragment/cluster size (%d) != "
4908 				 "block size (%d)", clustersize, blocksize);
4909 			goto failed_mount;
4910 		}
4911 		if (sbi->s_blocks_per_group > blocksize * 8) {
4912 			ext4_msg(sb, KERN_ERR,
4913 				 "#blocks per group too big: %lu",
4914 				 sbi->s_blocks_per_group);
4915 			goto failed_mount;
4916 		}
4917 		sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4918 		sbi->s_cluster_bits = 0;
4919 	}
4920 	sbi->s_cluster_ratio = clustersize / blocksize;
4921 
4922 	/* Do we have standard group size of clustersize * 8 blocks ? */
4923 	if (sbi->s_blocks_per_group == clustersize << 3)
4924 		set_opt2(sb, STD_GROUP_SIZE);
4925 
4926 	/*
4927 	 * Test whether we have more sectors than will fit in sector_t,
4928 	 * and whether the max offset is addressable by the page cache.
4929 	 */
4930 	err = generic_check_addressable(sb->s_blocksize_bits,
4931 					ext4_blocks_count(es));
4932 	if (err) {
4933 		ext4_msg(sb, KERN_ERR, "filesystem"
4934 			 " too large to mount safely on this system");
4935 		goto failed_mount;
4936 	}
4937 
4938 	if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4939 		goto cantfind_ext4;
4940 
4941 	/* check blocks count against device size */
4942 	blocks_count = sb_bdev_nr_blocks(sb);
4943 	if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4944 		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4945 		       "exceeds size of device (%llu blocks)",
4946 		       ext4_blocks_count(es), blocks_count);
4947 		goto failed_mount;
4948 	}
4949 
4950 	/*
4951 	 * It makes no sense for the first data block to be beyond the end
4952 	 * of the filesystem.
4953 	 */
4954 	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4955 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4956 			 "block %u is beyond end of filesystem (%llu)",
4957 			 le32_to_cpu(es->s_first_data_block),
4958 			 ext4_blocks_count(es));
4959 		goto failed_mount;
4960 	}
4961 	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4962 	    (sbi->s_cluster_ratio == 1)) {
4963 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4964 			 "block is 0 with a 1k block and cluster size");
4965 		goto failed_mount;
4966 	}
4967 
4968 	blocks_count = (ext4_blocks_count(es) -
4969 			le32_to_cpu(es->s_first_data_block) +
4970 			EXT4_BLOCKS_PER_GROUP(sb) - 1);
4971 	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4972 	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4973 		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4974 		       "(block count %llu, first data block %u, "
4975 		       "blocks per group %lu)", blocks_count,
4976 		       ext4_blocks_count(es),
4977 		       le32_to_cpu(es->s_first_data_block),
4978 		       EXT4_BLOCKS_PER_GROUP(sb));
4979 		goto failed_mount;
4980 	}
4981 	sbi->s_groups_count = blocks_count;
4982 	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4983 			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4984 	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4985 	    le32_to_cpu(es->s_inodes_count)) {
4986 		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4987 			 le32_to_cpu(es->s_inodes_count),
4988 			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4989 		ret = -EINVAL;
4990 		goto failed_mount;
4991 	}
4992 	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4993 		   EXT4_DESC_PER_BLOCK(sb);
4994 	if (ext4_has_feature_meta_bg(sb)) {
4995 		if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4996 			ext4_msg(sb, KERN_WARNING,
4997 				 "first meta block group too large: %u "
4998 				 "(group descriptor block count %u)",
4999 				 le32_to_cpu(es->s_first_meta_bg), db_count);
5000 			goto failed_mount;
5001 		}
5002 	}
5003 	rcu_assign_pointer(sbi->s_group_desc,
5004 			   kvmalloc_array(db_count,
5005 					  sizeof(struct buffer_head *),
5006 					  GFP_KERNEL));
5007 	if (sbi->s_group_desc == NULL) {
5008 		ext4_msg(sb, KERN_ERR, "not enough memory");
5009 		ret = -ENOMEM;
5010 		goto failed_mount;
5011 	}
5012 
5013 	bgl_lock_init(sbi->s_blockgroup_lock);
5014 
5015 	/* Pre-read the descriptors into the buffer cache */
5016 	for (i = 0; i < db_count; i++) {
5017 		block = descriptor_loc(sb, logical_sb_block, i);
5018 		ext4_sb_breadahead_unmovable(sb, block);
5019 	}
5020 
5021 	for (i = 0; i < db_count; i++) {
5022 		struct buffer_head *bh;
5023 
5024 		block = descriptor_loc(sb, logical_sb_block, i);
5025 		bh = ext4_sb_bread_unmovable(sb, block);
5026 		if (IS_ERR(bh)) {
5027 			ext4_msg(sb, KERN_ERR,
5028 			       "can't read group descriptor %d", i);
5029 			db_count = i;
5030 			ret = PTR_ERR(bh);
5031 			goto failed_mount2;
5032 		}
5033 		rcu_read_lock();
5034 		rcu_dereference(sbi->s_group_desc)[i] = bh;
5035 		rcu_read_unlock();
5036 	}
5037 	sbi->s_gdb_count = db_count;
5038 	if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
5039 		ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
5040 		ret = -EFSCORRUPTED;
5041 		goto failed_mount2;
5042 	}
5043 
5044 	timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5045 	spin_lock_init(&sbi->s_error_lock);
5046 	INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
5047 
5048 	/* Register extent status tree shrinker */
5049 	if (ext4_es_register_shrinker(sbi))
5050 		goto failed_mount3;
5051 
5052 	sbi->s_stripe = ext4_get_stripe_size(sbi);
5053 	sbi->s_extent_max_zeroout_kb = 32;
5054 
5055 	/*
5056 	 * set up enough so that it can read an inode
5057 	 */
5058 	sb->s_op = &ext4_sops;
5059 	sb->s_export_op = &ext4_export_ops;
5060 	sb->s_xattr = ext4_xattr_handlers;
5061 #ifdef CONFIG_FS_ENCRYPTION
5062 	sb->s_cop = &ext4_cryptops;
5063 #endif
5064 #ifdef CONFIG_FS_VERITY
5065 	sb->s_vop = &ext4_verityops;
5066 #endif
5067 #ifdef CONFIG_QUOTA
5068 	sb->dq_op = &ext4_quota_operations;
5069 	if (ext4_has_feature_quota(sb))
5070 		sb->s_qcop = &dquot_quotactl_sysfile_ops;
5071 	else
5072 		sb->s_qcop = &ext4_qctl_operations;
5073 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5074 #endif
5075 	memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5076 
5077 	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5078 	mutex_init(&sbi->s_orphan_lock);
5079 
5080 	/* Initialize fast commit stuff */
5081 	atomic_set(&sbi->s_fc_subtid, 0);
5082 	INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
5083 	INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
5084 	INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
5085 	INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
5086 	sbi->s_fc_bytes = 0;
5087 	ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
5088 	ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
5089 	spin_lock_init(&sbi->s_fc_lock);
5090 	memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
5091 	sbi->s_fc_replay_state.fc_regions = NULL;
5092 	sbi->s_fc_replay_state.fc_regions_size = 0;
5093 	sbi->s_fc_replay_state.fc_regions_used = 0;
5094 	sbi->s_fc_replay_state.fc_regions_valid = 0;
5095 	sbi->s_fc_replay_state.fc_modified_inodes = NULL;
5096 	sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
5097 	sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
5098 
5099 	sb->s_root = NULL;
5100 
5101 	needs_recovery = (es->s_last_orphan != 0 ||
5102 			  ext4_has_feature_orphan_present(sb) ||
5103 			  ext4_has_feature_journal_needs_recovery(sb));
5104 
5105 	if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
5106 		if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
5107 			goto failed_mount3a;
5108 
5109 	/*
5110 	 * The first inode we look at is the journal inode.  Don't try
5111 	 * root first: it may be modified in the journal!
5112 	 */
5113 	if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5114 		err = ext4_load_journal(sb, es, ctx->journal_devnum);
5115 		if (err)
5116 			goto failed_mount3a;
5117 	} else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5118 		   ext4_has_feature_journal_needs_recovery(sb)) {
5119 		ext4_msg(sb, KERN_ERR, "required journal recovery "
5120 		       "suppressed and not mounted read-only");
5121 		goto failed_mount_wq;
5122 	} else {
5123 		/* Nojournal mode, all journal mount options are illegal */
5124 		if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5125 			ext4_msg(sb, KERN_ERR, "can't mount with "
5126 				 "journal_checksum, fs mounted w/o journal");
5127 			goto failed_mount_wq;
5128 		}
5129 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5130 			ext4_msg(sb, KERN_ERR, "can't mount with "
5131 				 "journal_async_commit, fs mounted w/o journal");
5132 			goto failed_mount_wq;
5133 		}
5134 		if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5135 			ext4_msg(sb, KERN_ERR, "can't mount with "
5136 				 "commit=%lu, fs mounted w/o journal",
5137 				 sbi->s_commit_interval / HZ);
5138 			goto failed_mount_wq;
5139 		}
5140 		if (EXT4_MOUNT_DATA_FLAGS &
5141 		    (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5142 			ext4_msg(sb, KERN_ERR, "can't mount with "
5143 				 "data=, fs mounted w/o journal");
5144 			goto failed_mount_wq;
5145 		}
5146 		sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5147 		clear_opt(sb, JOURNAL_CHECKSUM);
5148 		clear_opt(sb, DATA_FLAGS);
5149 		clear_opt2(sb, JOURNAL_FAST_COMMIT);
5150 		sbi->s_journal = NULL;
5151 		needs_recovery = 0;
5152 		goto no_journal;
5153 	}
5154 
5155 	if (ext4_has_feature_64bit(sb) &&
5156 	    !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
5157 				       JBD2_FEATURE_INCOMPAT_64BIT)) {
5158 		ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
5159 		goto failed_mount_wq;
5160 	}
5161 
5162 	if (!set_journal_csum_feature_set(sb)) {
5163 		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
5164 			 "feature set");
5165 		goto failed_mount_wq;
5166 	}
5167 
5168 	if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
5169 		!jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
5170 					  JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
5171 		ext4_msg(sb, KERN_ERR,
5172 			"Failed to set fast commit journal feature");
5173 		goto failed_mount_wq;
5174 	}
5175 
5176 	/* We have now updated the journal if required, so we can
5177 	 * validate the data journaling mode. */
5178 	switch (test_opt(sb, DATA_FLAGS)) {
5179 	case 0:
5180 		/* No mode set, assume a default based on the journal
5181 		 * capabilities: ORDERED_DATA if the journal can
5182 		 * cope, else JOURNAL_DATA
5183 		 */
5184 		if (jbd2_journal_check_available_features
5185 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
5186 			set_opt(sb, ORDERED_DATA);
5187 			sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
5188 		} else {
5189 			set_opt(sb, JOURNAL_DATA);
5190 			sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
5191 		}
5192 		break;
5193 
5194 	case EXT4_MOUNT_ORDERED_DATA:
5195 	case EXT4_MOUNT_WRITEBACK_DATA:
5196 		if (!jbd2_journal_check_available_features
5197 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
5198 			ext4_msg(sb, KERN_ERR, "Journal does not support "
5199 			       "requested data journaling mode");
5200 			goto failed_mount_wq;
5201 		}
5202 		break;
5203 	default:
5204 		break;
5205 	}
5206 
5207 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
5208 	    test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5209 		ext4_msg(sb, KERN_ERR, "can't mount with "
5210 			"journal_async_commit in data=ordered mode");
5211 		goto failed_mount_wq;
5212 	}
5213 
5214 	set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
5215 
5216 	sbi->s_journal->j_submit_inode_data_buffers =
5217 		ext4_journal_submit_inode_data_buffers;
5218 	sbi->s_journal->j_finish_inode_data_buffers =
5219 		ext4_journal_finish_inode_data_buffers;
5220 
5221 no_journal:
5222 	if (!test_opt(sb, NO_MBCACHE)) {
5223 		sbi->s_ea_block_cache = ext4_xattr_create_cache();
5224 		if (!sbi->s_ea_block_cache) {
5225 			ext4_msg(sb, KERN_ERR,
5226 				 "Failed to create ea_block_cache");
5227 			goto failed_mount_wq;
5228 		}
5229 
5230 		if (ext4_has_feature_ea_inode(sb)) {
5231 			sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5232 			if (!sbi->s_ea_inode_cache) {
5233 				ext4_msg(sb, KERN_ERR,
5234 					 "Failed to create ea_inode_cache");
5235 				goto failed_mount_wq;
5236 			}
5237 		}
5238 	}
5239 
5240 	if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
5241 		ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
5242 		goto failed_mount_wq;
5243 	}
5244 
5245 	if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
5246 	    !ext4_has_feature_encrypt(sb)) {
5247 		ext4_set_feature_encrypt(sb);
5248 		ext4_commit_super(sb);
5249 	}
5250 
5251 	/*
5252 	 * Get the # of file system overhead blocks from the
5253 	 * superblock if present.
5254 	 */
5255 	if (es->s_overhead_clusters)
5256 		sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5257 	else {
5258 		err = ext4_calculate_overhead(sb);
5259 		if (err)
5260 			goto failed_mount_wq;
5261 	}
5262 
5263 	/*
5264 	 * The maximum number of concurrent works can be high and
5265 	 * concurrency isn't really necessary.  Limit it to 1.
5266 	 */
5267 	EXT4_SB(sb)->rsv_conversion_wq =
5268 		alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5269 	if (!EXT4_SB(sb)->rsv_conversion_wq) {
5270 		printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5271 		ret = -ENOMEM;
5272 		goto failed_mount4;
5273 	}
5274 
5275 	/*
5276 	 * The jbd2_journal_load will have done any necessary log recovery,
5277 	 * so we can safely mount the rest of the filesystem now.
5278 	 */
5279 
5280 	root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5281 	if (IS_ERR(root)) {
5282 		ext4_msg(sb, KERN_ERR, "get root inode failed");
5283 		ret = PTR_ERR(root);
5284 		root = NULL;
5285 		goto failed_mount4;
5286 	}
5287 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5288 		ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5289 		iput(root);
5290 		goto failed_mount4;
5291 	}
5292 
5293 	sb->s_root = d_make_root(root);
5294 	if (!sb->s_root) {
5295 		ext4_msg(sb, KERN_ERR, "get root dentry failed");
5296 		ret = -ENOMEM;
5297 		goto failed_mount4;
5298 	}
5299 
5300 	ret = ext4_setup_super(sb, es, sb_rdonly(sb));
5301 	if (ret == -EROFS) {
5302 		sb->s_flags |= SB_RDONLY;
5303 		ret = 0;
5304 	} else if (ret)
5305 		goto failed_mount4a;
5306 
5307 	ext4_set_resv_clusters(sb);
5308 
5309 	if (test_opt(sb, BLOCK_VALIDITY)) {
5310 		err = ext4_setup_system_zone(sb);
5311 		if (err) {
5312 			ext4_msg(sb, KERN_ERR, "failed to initialize system "
5313 				 "zone (%d)", err);
5314 			goto failed_mount4a;
5315 		}
5316 	}
5317 	ext4_fc_replay_cleanup(sb);
5318 
5319 	ext4_ext_init(sb);
5320 
5321 	/*
5322 	 * Enable optimize_scan if number of groups is > threshold. This can be
5323 	 * turned off by passing "mb_optimize_scan=0". This can also be
5324 	 * turned on forcefully by passing "mb_optimize_scan=1".
5325 	 */
5326 	if (ctx->mb_optimize_scan == 1)
5327 		set_opt2(sb, MB_OPTIMIZE_SCAN);
5328 	else if (ctx->mb_optimize_scan == 0)
5329 		clear_opt2(sb, MB_OPTIMIZE_SCAN);
5330 	else if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5331 		set_opt2(sb, MB_OPTIMIZE_SCAN);
5332 
5333 	err = ext4_mb_init(sb);
5334 	if (err) {
5335 		ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5336 			 err);
5337 		goto failed_mount5;
5338 	}
5339 
5340 	/*
5341 	 * We can only set up the journal commit callback once
5342 	 * mballoc is initialized
5343 	 */
5344 	if (sbi->s_journal)
5345 		sbi->s_journal->j_commit_callback =
5346 			ext4_journal_commit_callback;
5347 
5348 	block = ext4_count_free_clusters(sb);
5349 	ext4_free_blocks_count_set(sbi->s_es,
5350 				   EXT4_C2B(sbi, block));
5351 	err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5352 				  GFP_KERNEL);
5353 	if (!err) {
5354 		unsigned long freei = ext4_count_free_inodes(sb);
5355 		sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5356 		err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5357 					  GFP_KERNEL);
5358 	}
5359 	/*
5360 	 * Update the checksum after updating free space/inode
5361 	 * counters.  Otherwise the superblock can have an incorrect
5362 	 * checksum in the buffer cache until it is written out and
5363 	 * e2fsprogs programs trying to open a file system immediately
5364 	 * after it is mounted can fail.
5365 	 */
5366 	ext4_superblock_csum_set(sb);
5367 	if (!err)
5368 		err = percpu_counter_init(&sbi->s_dirs_counter,
5369 					  ext4_count_dirs(sb), GFP_KERNEL);
5370 	if (!err)
5371 		err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5372 					  GFP_KERNEL);
5373 	if (!err)
5374 		err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
5375 					  GFP_KERNEL);
5376 	if (!err)
5377 		err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5378 
5379 	if (err) {
5380 		ext4_msg(sb, KERN_ERR, "insufficient memory");
5381 		goto failed_mount6;
5382 	}
5383 
5384 	if (ext4_has_feature_flex_bg(sb))
5385 		if (!ext4_fill_flex_info(sb)) {
5386 			ext4_msg(sb, KERN_ERR,
5387 			       "unable to initialize "
5388 			       "flex_bg meta info!");
5389 			ret = -ENOMEM;
5390 			goto failed_mount6;
5391 		}
5392 
5393 	err = ext4_register_li_request(sb, first_not_zeroed);
5394 	if (err)
5395 		goto failed_mount6;
5396 
5397 	err = ext4_register_sysfs(sb);
5398 	if (err)
5399 		goto failed_mount7;
5400 
5401 	err = ext4_init_orphan_info(sb);
5402 	if (err)
5403 		goto failed_mount8;
5404 #ifdef CONFIG_QUOTA
5405 	/* Enable quota usage during mount. */
5406 	if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5407 		err = ext4_enable_quotas(sb);
5408 		if (err)
5409 			goto failed_mount9;
5410 	}
5411 #endif  /* CONFIG_QUOTA */
5412 
5413 	/*
5414 	 * Save the original bdev mapping's wb_err value which could be
5415 	 * used to detect the metadata async write error.
5416 	 */
5417 	spin_lock_init(&sbi->s_bdev_wb_lock);
5418 	errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5419 				 &sbi->s_bdev_wb_err);
5420 	sb->s_bdev->bd_super = sb;
5421 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5422 	ext4_orphan_cleanup(sb, es);
5423 	EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5424 	if (needs_recovery) {
5425 		ext4_msg(sb, KERN_INFO, "recovery complete");
5426 		err = ext4_mark_recovery_complete(sb, es);
5427 		if (err)
5428 			goto failed_mount9;
5429 	}
5430 
5431 	if (test_opt(sb, DISCARD)) {
5432 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
5433 		if (!blk_queue_discard(q))
5434 			ext4_msg(sb, KERN_WARNING,
5435 				 "mounting with \"discard\" option, but "
5436 				 "the device does not support discard");
5437 	}
5438 
5439 	if (es->s_error_count)
5440 		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5441 
5442 	/* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5443 	ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5444 	ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5445 	ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5446 	atomic_set(&sbi->s_warning_count, 0);
5447 	atomic_set(&sbi->s_msg_count, 0);
5448 
5449 	return 0;
5450 
5451 cantfind_ext4:
5452 	if (!silent)
5453 		ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5454 	goto failed_mount;
5455 
5456 failed_mount9:
5457 	ext4_release_orphan_info(sb);
5458 failed_mount8:
5459 	ext4_unregister_sysfs(sb);
5460 	kobject_put(&sbi->s_kobj);
5461 failed_mount7:
5462 	ext4_unregister_li_request(sb);
5463 failed_mount6:
5464 	ext4_mb_release(sb);
5465 	rcu_read_lock();
5466 	flex_groups = rcu_dereference(sbi->s_flex_groups);
5467 	if (flex_groups) {
5468 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5469 			kvfree(flex_groups[i]);
5470 		kvfree(flex_groups);
5471 	}
5472 	rcu_read_unlock();
5473 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
5474 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
5475 	percpu_counter_destroy(&sbi->s_dirs_counter);
5476 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5477 	percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
5478 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
5479 failed_mount5:
5480 	ext4_ext_release(sb);
5481 	ext4_release_system_zone(sb);
5482 failed_mount4a:
5483 	dput(sb->s_root);
5484 	sb->s_root = NULL;
5485 failed_mount4:
5486 	ext4_msg(sb, KERN_ERR, "mount failed");
5487 	if (EXT4_SB(sb)->rsv_conversion_wq)
5488 		destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5489 failed_mount_wq:
5490 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5491 	sbi->s_ea_inode_cache = NULL;
5492 
5493 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5494 	sbi->s_ea_block_cache = NULL;
5495 
5496 	if (sbi->s_journal) {
5497 		/* flush s_error_work before journal destroy. */
5498 		flush_work(&sbi->s_error_work);
5499 		jbd2_journal_destroy(sbi->s_journal);
5500 		sbi->s_journal = NULL;
5501 	}
5502 failed_mount3a:
5503 	ext4_es_unregister_shrinker(sbi);
5504 failed_mount3:
5505 	/* flush s_error_work before sbi destroy */
5506 	flush_work(&sbi->s_error_work);
5507 	del_timer_sync(&sbi->s_err_report);
5508 	ext4_stop_mmpd(sbi);
5509 failed_mount2:
5510 	rcu_read_lock();
5511 	group_desc = rcu_dereference(sbi->s_group_desc);
5512 	for (i = 0; i < db_count; i++)
5513 		brelse(group_desc[i]);
5514 	kvfree(group_desc);
5515 	rcu_read_unlock();
5516 failed_mount:
5517 	if (sbi->s_chksum_driver)
5518 		crypto_free_shash(sbi->s_chksum_driver);
5519 
5520 #ifdef CONFIG_UNICODE
5521 	utf8_unload(sb->s_encoding);
5522 #endif
5523 
5524 #ifdef CONFIG_QUOTA
5525 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5526 		kfree(get_qf_name(sb, sbi, i));
5527 #endif
5528 	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5529 	/* ext4_blkdev_remove() calls kill_bdev(), release bh before it. */
5530 	brelse(bh);
5531 	ext4_blkdev_remove(sbi);
5532 out_fail:
5533 	sb->s_fs_info = NULL;
5534 	return err ? err : ret;
5535 }
5536 
5537 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5538 {
5539 	struct ext4_fs_context *ctx = fc->fs_private;
5540 	struct ext4_sb_info *sbi;
5541 	const char *descr;
5542 	int ret;
5543 
5544 	sbi = ext4_alloc_sbi(sb);
5545 	if (!sbi)
5546 		ret = -ENOMEM;
5547 
5548 	fc->s_fs_info = sbi;
5549 
5550 	/* Cleanup superblock name */
5551 	strreplace(sb->s_id, '/', '!');
5552 
5553 	sbi->s_sb_block = 1;	/* Default super block location */
5554 	if (ctx->spec & EXT4_SPEC_s_sb_block)
5555 		sbi->s_sb_block = ctx->s_sb_block;
5556 
5557 	ret = __ext4_fill_super(fc, sb);
5558 	if (ret < 0)
5559 		goto free_sbi;
5560 
5561 	if (sbi->s_journal) {
5562 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5563 			descr = " journalled data mode";
5564 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5565 			descr = " ordered data mode";
5566 		else
5567 			descr = " writeback data mode";
5568 	} else
5569 		descr = "out journal";
5570 
5571 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5572 		ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5573 			 "Quota mode: %s.", descr, ext4_quota_mode(sb));
5574 
5575 	return 0;
5576 
5577 free_sbi:
5578 	ext4_free_sbi(sbi);
5579 	fc->s_fs_info = NULL;
5580 	return ret;
5581 }
5582 
5583 static int ext4_get_tree(struct fs_context *fc)
5584 {
5585 	return get_tree_bdev(fc, ext4_fill_super);
5586 }
5587 
5588 /*
5589  * Setup any per-fs journal parameters now.  We'll do this both on
5590  * initial mount, once the journal has been initialised but before we've
5591  * done any recovery; and again on any subsequent remount.
5592  */
5593 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5594 {
5595 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5596 
5597 	journal->j_commit_interval = sbi->s_commit_interval;
5598 	journal->j_min_batch_time = sbi->s_min_batch_time;
5599 	journal->j_max_batch_time = sbi->s_max_batch_time;
5600 	ext4_fc_init(sb, journal);
5601 
5602 	write_lock(&journal->j_state_lock);
5603 	if (test_opt(sb, BARRIER))
5604 		journal->j_flags |= JBD2_BARRIER;
5605 	else
5606 		journal->j_flags &= ~JBD2_BARRIER;
5607 	if (test_opt(sb, DATA_ERR_ABORT))
5608 		journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5609 	else
5610 		journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5611 	write_unlock(&journal->j_state_lock);
5612 }
5613 
5614 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5615 					     unsigned int journal_inum)
5616 {
5617 	struct inode *journal_inode;
5618 
5619 	/*
5620 	 * Test for the existence of a valid inode on disk.  Bad things
5621 	 * happen if we iget() an unused inode, as the subsequent iput()
5622 	 * will try to delete it.
5623 	 */
5624 	journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5625 	if (IS_ERR(journal_inode)) {
5626 		ext4_msg(sb, KERN_ERR, "no journal found");
5627 		return NULL;
5628 	}
5629 	if (!journal_inode->i_nlink) {
5630 		make_bad_inode(journal_inode);
5631 		iput(journal_inode);
5632 		ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5633 		return NULL;
5634 	}
5635 
5636 	jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5637 		  journal_inode, journal_inode->i_size);
5638 	if (!S_ISREG(journal_inode->i_mode)) {
5639 		ext4_msg(sb, KERN_ERR, "invalid journal inode");
5640 		iput(journal_inode);
5641 		return NULL;
5642 	}
5643 	return journal_inode;
5644 }
5645 
5646 static journal_t *ext4_get_journal(struct super_block *sb,
5647 				   unsigned int journal_inum)
5648 {
5649 	struct inode *journal_inode;
5650 	journal_t *journal;
5651 
5652 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5653 		return NULL;
5654 
5655 	journal_inode = ext4_get_journal_inode(sb, journal_inum);
5656 	if (!journal_inode)
5657 		return NULL;
5658 
5659 	journal = jbd2_journal_init_inode(journal_inode);
5660 	if (!journal) {
5661 		ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5662 		iput(journal_inode);
5663 		return NULL;
5664 	}
5665 	journal->j_private = sb;
5666 	ext4_init_journal_params(sb, journal);
5667 	return journal;
5668 }
5669 
5670 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5671 				       dev_t j_dev)
5672 {
5673 	struct buffer_head *bh;
5674 	journal_t *journal;
5675 	ext4_fsblk_t start;
5676 	ext4_fsblk_t len;
5677 	int hblock, blocksize;
5678 	ext4_fsblk_t sb_block;
5679 	unsigned long offset;
5680 	struct ext4_super_block *es;
5681 	struct block_device *bdev;
5682 
5683 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5684 		return NULL;
5685 
5686 	bdev = ext4_blkdev_get(j_dev, sb);
5687 	if (bdev == NULL)
5688 		return NULL;
5689 
5690 	blocksize = sb->s_blocksize;
5691 	hblock = bdev_logical_block_size(bdev);
5692 	if (blocksize < hblock) {
5693 		ext4_msg(sb, KERN_ERR,
5694 			"blocksize too small for journal device");
5695 		goto out_bdev;
5696 	}
5697 
5698 	sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5699 	offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5700 	set_blocksize(bdev, blocksize);
5701 	if (!(bh = __bread(bdev, sb_block, blocksize))) {
5702 		ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5703 		       "external journal");
5704 		goto out_bdev;
5705 	}
5706 
5707 	es = (struct ext4_super_block *) (bh->b_data + offset);
5708 	if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5709 	    !(le32_to_cpu(es->s_feature_incompat) &
5710 	      EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5711 		ext4_msg(sb, KERN_ERR, "external journal has "
5712 					"bad superblock");
5713 		brelse(bh);
5714 		goto out_bdev;
5715 	}
5716 
5717 	if ((le32_to_cpu(es->s_feature_ro_compat) &
5718 	     EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5719 	    es->s_checksum != ext4_superblock_csum(sb, es)) {
5720 		ext4_msg(sb, KERN_ERR, "external journal has "
5721 				       "corrupt superblock");
5722 		brelse(bh);
5723 		goto out_bdev;
5724 	}
5725 
5726 	if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5727 		ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5728 		brelse(bh);
5729 		goto out_bdev;
5730 	}
5731 
5732 	len = ext4_blocks_count(es);
5733 	start = sb_block + 1;
5734 	brelse(bh);	/* we're done with the superblock */
5735 
5736 	journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5737 					start, len, blocksize);
5738 	if (!journal) {
5739 		ext4_msg(sb, KERN_ERR, "failed to create device journal");
5740 		goto out_bdev;
5741 	}
5742 	journal->j_private = sb;
5743 	if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5744 		ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5745 		goto out_journal;
5746 	}
5747 	if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5748 		ext4_msg(sb, KERN_ERR, "External journal has more than one "
5749 					"user (unsupported) - %d",
5750 			be32_to_cpu(journal->j_superblock->s_nr_users));
5751 		goto out_journal;
5752 	}
5753 	EXT4_SB(sb)->s_journal_bdev = bdev;
5754 	ext4_init_journal_params(sb, journal);
5755 	return journal;
5756 
5757 out_journal:
5758 	jbd2_journal_destroy(journal);
5759 out_bdev:
5760 	ext4_blkdev_put(bdev);
5761 	return NULL;
5762 }
5763 
5764 static int ext4_load_journal(struct super_block *sb,
5765 			     struct ext4_super_block *es,
5766 			     unsigned long journal_devnum)
5767 {
5768 	journal_t *journal;
5769 	unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5770 	dev_t journal_dev;
5771 	int err = 0;
5772 	int really_read_only;
5773 	int journal_dev_ro;
5774 
5775 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5776 		return -EFSCORRUPTED;
5777 
5778 	if (journal_devnum &&
5779 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5780 		ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5781 			"numbers have changed");
5782 		journal_dev = new_decode_dev(journal_devnum);
5783 	} else
5784 		journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5785 
5786 	if (journal_inum && journal_dev) {
5787 		ext4_msg(sb, KERN_ERR,
5788 			 "filesystem has both journal inode and journal device!");
5789 		return -EINVAL;
5790 	}
5791 
5792 	if (journal_inum) {
5793 		journal = ext4_get_journal(sb, journal_inum);
5794 		if (!journal)
5795 			return -EINVAL;
5796 	} else {
5797 		journal = ext4_get_dev_journal(sb, journal_dev);
5798 		if (!journal)
5799 			return -EINVAL;
5800 	}
5801 
5802 	journal_dev_ro = bdev_read_only(journal->j_dev);
5803 	really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5804 
5805 	if (journal_dev_ro && !sb_rdonly(sb)) {
5806 		ext4_msg(sb, KERN_ERR,
5807 			 "journal device read-only, try mounting with '-o ro'");
5808 		err = -EROFS;
5809 		goto err_out;
5810 	}
5811 
5812 	/*
5813 	 * Are we loading a blank journal or performing recovery after a
5814 	 * crash?  For recovery, we need to check in advance whether we
5815 	 * can get read-write access to the device.
5816 	 */
5817 	if (ext4_has_feature_journal_needs_recovery(sb)) {
5818 		if (sb_rdonly(sb)) {
5819 			ext4_msg(sb, KERN_INFO, "INFO: recovery "
5820 					"required on readonly filesystem");
5821 			if (really_read_only) {
5822 				ext4_msg(sb, KERN_ERR, "write access "
5823 					"unavailable, cannot proceed "
5824 					"(try mounting with noload)");
5825 				err = -EROFS;
5826 				goto err_out;
5827 			}
5828 			ext4_msg(sb, KERN_INFO, "write access will "
5829 			       "be enabled during recovery");
5830 		}
5831 	}
5832 
5833 	if (!(journal->j_flags & JBD2_BARRIER))
5834 		ext4_msg(sb, KERN_INFO, "barriers disabled");
5835 
5836 	if (!ext4_has_feature_journal_needs_recovery(sb))
5837 		err = jbd2_journal_wipe(journal, !really_read_only);
5838 	if (!err) {
5839 		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5840 		if (save)
5841 			memcpy(save, ((char *) es) +
5842 			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5843 		err = jbd2_journal_load(journal);
5844 		if (save)
5845 			memcpy(((char *) es) + EXT4_S_ERR_START,
5846 			       save, EXT4_S_ERR_LEN);
5847 		kfree(save);
5848 	}
5849 
5850 	if (err) {
5851 		ext4_msg(sb, KERN_ERR, "error loading journal");
5852 		goto err_out;
5853 	}
5854 
5855 	EXT4_SB(sb)->s_journal = journal;
5856 	err = ext4_clear_journal_err(sb, es);
5857 	if (err) {
5858 		EXT4_SB(sb)->s_journal = NULL;
5859 		jbd2_journal_destroy(journal);
5860 		return err;
5861 	}
5862 
5863 	if (!really_read_only && journal_devnum &&
5864 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5865 		es->s_journal_dev = cpu_to_le32(journal_devnum);
5866 
5867 		/* Make sure we flush the recovery flag to disk. */
5868 		ext4_commit_super(sb);
5869 	}
5870 
5871 	return 0;
5872 
5873 err_out:
5874 	jbd2_journal_destroy(journal);
5875 	return err;
5876 }
5877 
5878 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5879 static void ext4_update_super(struct super_block *sb)
5880 {
5881 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5882 	struct ext4_super_block *es = sbi->s_es;
5883 	struct buffer_head *sbh = sbi->s_sbh;
5884 
5885 	lock_buffer(sbh);
5886 	/*
5887 	 * If the file system is mounted read-only, don't update the
5888 	 * superblock write time.  This avoids updating the superblock
5889 	 * write time when we are mounting the root file system
5890 	 * read/only but we need to replay the journal; at that point,
5891 	 * for people who are east of GMT and who make their clock
5892 	 * tick in localtime for Windows bug-for-bug compatibility,
5893 	 * the clock is set in the future, and this will cause e2fsck
5894 	 * to complain and force a full file system check.
5895 	 */
5896 	if (!(sb->s_flags & SB_RDONLY))
5897 		ext4_update_tstamp(es, s_wtime);
5898 	es->s_kbytes_written =
5899 		cpu_to_le64(sbi->s_kbytes_written +
5900 		    ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5901 		      sbi->s_sectors_written_start) >> 1));
5902 	if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5903 		ext4_free_blocks_count_set(es,
5904 			EXT4_C2B(sbi, percpu_counter_sum_positive(
5905 				&sbi->s_freeclusters_counter)));
5906 	if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5907 		es->s_free_inodes_count =
5908 			cpu_to_le32(percpu_counter_sum_positive(
5909 				&sbi->s_freeinodes_counter));
5910 	/* Copy error information to the on-disk superblock */
5911 	spin_lock(&sbi->s_error_lock);
5912 	if (sbi->s_add_error_count > 0) {
5913 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5914 		if (!es->s_first_error_time && !es->s_first_error_time_hi) {
5915 			__ext4_update_tstamp(&es->s_first_error_time,
5916 					     &es->s_first_error_time_hi,
5917 					     sbi->s_first_error_time);
5918 			strncpy(es->s_first_error_func, sbi->s_first_error_func,
5919 				sizeof(es->s_first_error_func));
5920 			es->s_first_error_line =
5921 				cpu_to_le32(sbi->s_first_error_line);
5922 			es->s_first_error_ino =
5923 				cpu_to_le32(sbi->s_first_error_ino);
5924 			es->s_first_error_block =
5925 				cpu_to_le64(sbi->s_first_error_block);
5926 			es->s_first_error_errcode =
5927 				ext4_errno_to_code(sbi->s_first_error_code);
5928 		}
5929 		__ext4_update_tstamp(&es->s_last_error_time,
5930 				     &es->s_last_error_time_hi,
5931 				     sbi->s_last_error_time);
5932 		strncpy(es->s_last_error_func, sbi->s_last_error_func,
5933 			sizeof(es->s_last_error_func));
5934 		es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
5935 		es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
5936 		es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
5937 		es->s_last_error_errcode =
5938 				ext4_errno_to_code(sbi->s_last_error_code);
5939 		/*
5940 		 * Start the daily error reporting function if it hasn't been
5941 		 * started already
5942 		 */
5943 		if (!es->s_error_count)
5944 			mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
5945 		le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
5946 		sbi->s_add_error_count = 0;
5947 	}
5948 	spin_unlock(&sbi->s_error_lock);
5949 
5950 	ext4_superblock_csum_set(sb);
5951 	unlock_buffer(sbh);
5952 }
5953 
5954 static int ext4_commit_super(struct super_block *sb)
5955 {
5956 	struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5957 	int error = 0;
5958 
5959 	if (!sbh)
5960 		return -EINVAL;
5961 	if (block_device_ejected(sb))
5962 		return -ENODEV;
5963 
5964 	ext4_update_super(sb);
5965 
5966 	if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5967 		/*
5968 		 * Oh, dear.  A previous attempt to write the
5969 		 * superblock failed.  This could happen because the
5970 		 * USB device was yanked out.  Or it could happen to
5971 		 * be a transient write error and maybe the block will
5972 		 * be remapped.  Nothing we can do but to retry the
5973 		 * write and hope for the best.
5974 		 */
5975 		ext4_msg(sb, KERN_ERR, "previous I/O error to "
5976 		       "superblock detected");
5977 		clear_buffer_write_io_error(sbh);
5978 		set_buffer_uptodate(sbh);
5979 	}
5980 	BUFFER_TRACE(sbh, "marking dirty");
5981 	mark_buffer_dirty(sbh);
5982 	error = __sync_dirty_buffer(sbh,
5983 		REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5984 	if (buffer_write_io_error(sbh)) {
5985 		ext4_msg(sb, KERN_ERR, "I/O error while writing "
5986 		       "superblock");
5987 		clear_buffer_write_io_error(sbh);
5988 		set_buffer_uptodate(sbh);
5989 	}
5990 	return error;
5991 }
5992 
5993 /*
5994  * Have we just finished recovery?  If so, and if we are mounting (or
5995  * remounting) the filesystem readonly, then we will end up with a
5996  * consistent fs on disk.  Record that fact.
5997  */
5998 static int ext4_mark_recovery_complete(struct super_block *sb,
5999 				       struct ext4_super_block *es)
6000 {
6001 	int err;
6002 	journal_t *journal = EXT4_SB(sb)->s_journal;
6003 
6004 	if (!ext4_has_feature_journal(sb)) {
6005 		if (journal != NULL) {
6006 			ext4_error(sb, "Journal got removed while the fs was "
6007 				   "mounted!");
6008 			return -EFSCORRUPTED;
6009 		}
6010 		return 0;
6011 	}
6012 	jbd2_journal_lock_updates(journal);
6013 	err = jbd2_journal_flush(journal, 0);
6014 	if (err < 0)
6015 		goto out;
6016 
6017 	if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6018 	    ext4_has_feature_orphan_present(sb))) {
6019 		if (!ext4_orphan_file_empty(sb)) {
6020 			ext4_error(sb, "Orphan file not empty on read-only fs.");
6021 			err = -EFSCORRUPTED;
6022 			goto out;
6023 		}
6024 		ext4_clear_feature_journal_needs_recovery(sb);
6025 		ext4_clear_feature_orphan_present(sb);
6026 		ext4_commit_super(sb);
6027 	}
6028 out:
6029 	jbd2_journal_unlock_updates(journal);
6030 	return err;
6031 }
6032 
6033 /*
6034  * If we are mounting (or read-write remounting) a filesystem whose journal
6035  * has recorded an error from a previous lifetime, move that error to the
6036  * main filesystem now.
6037  */
6038 static int ext4_clear_journal_err(struct super_block *sb,
6039 				   struct ext4_super_block *es)
6040 {
6041 	journal_t *journal;
6042 	int j_errno;
6043 	const char *errstr;
6044 
6045 	if (!ext4_has_feature_journal(sb)) {
6046 		ext4_error(sb, "Journal got removed while the fs was mounted!");
6047 		return -EFSCORRUPTED;
6048 	}
6049 
6050 	journal = EXT4_SB(sb)->s_journal;
6051 
6052 	/*
6053 	 * Now check for any error status which may have been recorded in the
6054 	 * journal by a prior ext4_error() or ext4_abort()
6055 	 */
6056 
6057 	j_errno = jbd2_journal_errno(journal);
6058 	if (j_errno) {
6059 		char nbuf[16];
6060 
6061 		errstr = ext4_decode_error(sb, j_errno, nbuf);
6062 		ext4_warning(sb, "Filesystem error recorded "
6063 			     "from previous mount: %s", errstr);
6064 		ext4_warning(sb, "Marking fs in need of filesystem check.");
6065 
6066 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6067 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6068 		ext4_commit_super(sb);
6069 
6070 		jbd2_journal_clear_err(journal);
6071 		jbd2_journal_update_sb_errno(journal);
6072 	}
6073 	return 0;
6074 }
6075 
6076 /*
6077  * Force the running and committing transactions to commit,
6078  * and wait on the commit.
6079  */
6080 int ext4_force_commit(struct super_block *sb)
6081 {
6082 	journal_t *journal;
6083 
6084 	if (sb_rdonly(sb))
6085 		return 0;
6086 
6087 	journal = EXT4_SB(sb)->s_journal;
6088 	return ext4_journal_force_commit(journal);
6089 }
6090 
6091 static int ext4_sync_fs(struct super_block *sb, int wait)
6092 {
6093 	int ret = 0;
6094 	tid_t target;
6095 	bool needs_barrier = false;
6096 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6097 
6098 	if (unlikely(ext4_forced_shutdown(sbi)))
6099 		return 0;
6100 
6101 	trace_ext4_sync_fs(sb, wait);
6102 	flush_workqueue(sbi->rsv_conversion_wq);
6103 	/*
6104 	 * Writeback quota in non-journalled quota case - journalled quota has
6105 	 * no dirty dquots
6106 	 */
6107 	dquot_writeback_dquots(sb, -1);
6108 	/*
6109 	 * Data writeback is possible w/o journal transaction, so barrier must
6110 	 * being sent at the end of the function. But we can skip it if
6111 	 * transaction_commit will do it for us.
6112 	 */
6113 	if (sbi->s_journal) {
6114 		target = jbd2_get_latest_transaction(sbi->s_journal);
6115 		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6116 		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6117 			needs_barrier = true;
6118 
6119 		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6120 			if (wait)
6121 				ret = jbd2_log_wait_commit(sbi->s_journal,
6122 							   target);
6123 		}
6124 	} else if (wait && test_opt(sb, BARRIER))
6125 		needs_barrier = true;
6126 	if (needs_barrier) {
6127 		int err;
6128 		err = blkdev_issue_flush(sb->s_bdev);
6129 		if (!ret)
6130 			ret = err;
6131 	}
6132 
6133 	return ret;
6134 }
6135 
6136 /*
6137  * LVM calls this function before a (read-only) snapshot is created.  This
6138  * gives us a chance to flush the journal completely and mark the fs clean.
6139  *
6140  * Note that only this function cannot bring a filesystem to be in a clean
6141  * state independently. It relies on upper layer to stop all data & metadata
6142  * modifications.
6143  */
6144 static int ext4_freeze(struct super_block *sb)
6145 {
6146 	int error = 0;
6147 	journal_t *journal;
6148 
6149 	if (sb_rdonly(sb))
6150 		return 0;
6151 
6152 	journal = EXT4_SB(sb)->s_journal;
6153 
6154 	if (journal) {
6155 		/* Now we set up the journal barrier. */
6156 		jbd2_journal_lock_updates(journal);
6157 
6158 		/*
6159 		 * Don't clear the needs_recovery flag if we failed to
6160 		 * flush the journal.
6161 		 */
6162 		error = jbd2_journal_flush(journal, 0);
6163 		if (error < 0)
6164 			goto out;
6165 
6166 		/* Journal blocked and flushed, clear needs_recovery flag. */
6167 		ext4_clear_feature_journal_needs_recovery(sb);
6168 		if (ext4_orphan_file_empty(sb))
6169 			ext4_clear_feature_orphan_present(sb);
6170 	}
6171 
6172 	error = ext4_commit_super(sb);
6173 out:
6174 	if (journal)
6175 		/* we rely on upper layer to stop further updates */
6176 		jbd2_journal_unlock_updates(journal);
6177 	return error;
6178 }
6179 
6180 /*
6181  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6182  * flag here, even though the filesystem is not technically dirty yet.
6183  */
6184 static int ext4_unfreeze(struct super_block *sb)
6185 {
6186 	if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
6187 		return 0;
6188 
6189 	if (EXT4_SB(sb)->s_journal) {
6190 		/* Reset the needs_recovery flag before the fs is unlocked. */
6191 		ext4_set_feature_journal_needs_recovery(sb);
6192 		if (ext4_has_feature_orphan_file(sb))
6193 			ext4_set_feature_orphan_present(sb);
6194 	}
6195 
6196 	ext4_commit_super(sb);
6197 	return 0;
6198 }
6199 
6200 /*
6201  * Structure to save mount options for ext4_remount's benefit
6202  */
6203 struct ext4_mount_options {
6204 	unsigned long s_mount_opt;
6205 	unsigned long s_mount_opt2;
6206 	kuid_t s_resuid;
6207 	kgid_t s_resgid;
6208 	unsigned long s_commit_interval;
6209 	u32 s_min_batch_time, s_max_batch_time;
6210 #ifdef CONFIG_QUOTA
6211 	int s_jquota_fmt;
6212 	char *s_qf_names[EXT4_MAXQUOTAS];
6213 #endif
6214 };
6215 
6216 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6217 {
6218 	struct ext4_fs_context *ctx = fc->fs_private;
6219 	struct ext4_super_block *es;
6220 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6221 	unsigned long old_sb_flags;
6222 	struct ext4_mount_options old_opts;
6223 	ext4_group_t g;
6224 	int err = 0;
6225 #ifdef CONFIG_QUOTA
6226 	int enable_quota = 0;
6227 	int i, j;
6228 	char *to_free[EXT4_MAXQUOTAS];
6229 #endif
6230 
6231 	ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6232 
6233 	/* Store the original options */
6234 	old_sb_flags = sb->s_flags;
6235 	old_opts.s_mount_opt = sbi->s_mount_opt;
6236 	old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6237 	old_opts.s_resuid = sbi->s_resuid;
6238 	old_opts.s_resgid = sbi->s_resgid;
6239 	old_opts.s_commit_interval = sbi->s_commit_interval;
6240 	old_opts.s_min_batch_time = sbi->s_min_batch_time;
6241 	old_opts.s_max_batch_time = sbi->s_max_batch_time;
6242 #ifdef CONFIG_QUOTA
6243 	old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6244 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6245 		if (sbi->s_qf_names[i]) {
6246 			char *qf_name = get_qf_name(sb, sbi, i);
6247 
6248 			old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6249 			if (!old_opts.s_qf_names[i]) {
6250 				for (j = 0; j < i; j++)
6251 					kfree(old_opts.s_qf_names[j]);
6252 				return -ENOMEM;
6253 			}
6254 		} else
6255 			old_opts.s_qf_names[i] = NULL;
6256 #endif
6257 	if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6258 		ctx->journal_ioprio =
6259 			sbi->s_journal->j_task->io_context->ioprio;
6260 
6261 	ext4_apply_options(fc, sb);
6262 
6263 	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6264 	    test_opt(sb, JOURNAL_CHECKSUM)) {
6265 		ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6266 			 "during remount not supported; ignoring");
6267 		sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6268 	}
6269 
6270 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6271 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6272 			ext4_msg(sb, KERN_ERR, "can't mount with "
6273 				 "both data=journal and delalloc");
6274 			err = -EINVAL;
6275 			goto restore_opts;
6276 		}
6277 		if (test_opt(sb, DIOREAD_NOLOCK)) {
6278 			ext4_msg(sb, KERN_ERR, "can't mount with "
6279 				 "both data=journal and dioread_nolock");
6280 			err = -EINVAL;
6281 			goto restore_opts;
6282 		}
6283 	} else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6284 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6285 			ext4_msg(sb, KERN_ERR, "can't mount with "
6286 				"journal_async_commit in data=ordered mode");
6287 			err = -EINVAL;
6288 			goto restore_opts;
6289 		}
6290 	}
6291 
6292 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6293 		ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6294 		err = -EINVAL;
6295 		goto restore_opts;
6296 	}
6297 
6298 	if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
6299 		ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6300 
6301 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6302 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6303 
6304 	es = sbi->s_es;
6305 
6306 	if (sbi->s_journal) {
6307 		ext4_init_journal_params(sb, sbi->s_journal);
6308 		set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6309 	}
6310 
6311 	/* Flush outstanding errors before changing fs state */
6312 	flush_work(&sbi->s_error_work);
6313 
6314 	if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6315 		if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
6316 			err = -EROFS;
6317 			goto restore_opts;
6318 		}
6319 
6320 		if (fc->sb_flags & SB_RDONLY) {
6321 			err = sync_filesystem(sb);
6322 			if (err < 0)
6323 				goto restore_opts;
6324 			err = dquot_suspend(sb, -1);
6325 			if (err < 0)
6326 				goto restore_opts;
6327 
6328 			/*
6329 			 * First of all, the unconditional stuff we have to do
6330 			 * to disable replay of the journal when we next remount
6331 			 */
6332 			sb->s_flags |= SB_RDONLY;
6333 
6334 			/*
6335 			 * OK, test if we are remounting a valid rw partition
6336 			 * readonly, and if so set the rdonly flag and then
6337 			 * mark the partition as valid again.
6338 			 */
6339 			if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6340 			    (sbi->s_mount_state & EXT4_VALID_FS))
6341 				es->s_state = cpu_to_le16(sbi->s_mount_state);
6342 
6343 			if (sbi->s_journal) {
6344 				/*
6345 				 * We let remount-ro finish even if marking fs
6346 				 * as clean failed...
6347 				 */
6348 				ext4_mark_recovery_complete(sb, es);
6349 			}
6350 		} else {
6351 			/* Make sure we can mount this feature set readwrite */
6352 			if (ext4_has_feature_readonly(sb) ||
6353 			    !ext4_feature_set_ok(sb, 0)) {
6354 				err = -EROFS;
6355 				goto restore_opts;
6356 			}
6357 			/*
6358 			 * Make sure the group descriptor checksums
6359 			 * are sane.  If they aren't, refuse to remount r/w.
6360 			 */
6361 			for (g = 0; g < sbi->s_groups_count; g++) {
6362 				struct ext4_group_desc *gdp =
6363 					ext4_get_group_desc(sb, g, NULL);
6364 
6365 				if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6366 					ext4_msg(sb, KERN_ERR,
6367 	       "ext4_remount: Checksum for group %u failed (%u!=%u)",
6368 		g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6369 					       le16_to_cpu(gdp->bg_checksum));
6370 					err = -EFSBADCRC;
6371 					goto restore_opts;
6372 				}
6373 			}
6374 
6375 			/*
6376 			 * If we have an unprocessed orphan list hanging
6377 			 * around from a previously readonly bdev mount,
6378 			 * require a full umount/remount for now.
6379 			 */
6380 			if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6381 				ext4_msg(sb, KERN_WARNING, "Couldn't "
6382 				       "remount RDWR because of unprocessed "
6383 				       "orphan inode list.  Please "
6384 				       "umount/remount instead");
6385 				err = -EINVAL;
6386 				goto restore_opts;
6387 			}
6388 
6389 			/*
6390 			 * Mounting a RDONLY partition read-write, so reread
6391 			 * and store the current valid flag.  (It may have
6392 			 * been changed by e2fsck since we originally mounted
6393 			 * the partition.)
6394 			 */
6395 			if (sbi->s_journal) {
6396 				err = ext4_clear_journal_err(sb, es);
6397 				if (err)
6398 					goto restore_opts;
6399 			}
6400 			sbi->s_mount_state = le16_to_cpu(es->s_state);
6401 
6402 			err = ext4_setup_super(sb, es, 0);
6403 			if (err)
6404 				goto restore_opts;
6405 
6406 			sb->s_flags &= ~SB_RDONLY;
6407 			if (ext4_has_feature_mmp(sb))
6408 				if (ext4_multi_mount_protect(sb,
6409 						le64_to_cpu(es->s_mmp_block))) {
6410 					err = -EROFS;
6411 					goto restore_opts;
6412 				}
6413 #ifdef CONFIG_QUOTA
6414 			enable_quota = 1;
6415 #endif
6416 		}
6417 	}
6418 
6419 	/*
6420 	 * Reinitialize lazy itable initialization thread based on
6421 	 * current settings
6422 	 */
6423 	if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6424 		ext4_unregister_li_request(sb);
6425 	else {
6426 		ext4_group_t first_not_zeroed;
6427 		first_not_zeroed = ext4_has_uninit_itable(sb);
6428 		ext4_register_li_request(sb, first_not_zeroed);
6429 	}
6430 
6431 	/*
6432 	 * Handle creation of system zone data early because it can fail.
6433 	 * Releasing of existing data is done when we are sure remount will
6434 	 * succeed.
6435 	 */
6436 	if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6437 		err = ext4_setup_system_zone(sb);
6438 		if (err)
6439 			goto restore_opts;
6440 	}
6441 
6442 	if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6443 		err = ext4_commit_super(sb);
6444 		if (err)
6445 			goto restore_opts;
6446 	}
6447 
6448 #ifdef CONFIG_QUOTA
6449 	/* Release old quota file names */
6450 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6451 		kfree(old_opts.s_qf_names[i]);
6452 	if (enable_quota) {
6453 		if (sb_any_quota_suspended(sb))
6454 			dquot_resume(sb, -1);
6455 		else if (ext4_has_feature_quota(sb)) {
6456 			err = ext4_enable_quotas(sb);
6457 			if (err)
6458 				goto restore_opts;
6459 		}
6460 	}
6461 #endif
6462 	if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6463 		ext4_release_system_zone(sb);
6464 
6465 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6466 		ext4_stop_mmpd(sbi);
6467 
6468 	return 0;
6469 
6470 restore_opts:
6471 	sb->s_flags = old_sb_flags;
6472 	sbi->s_mount_opt = old_opts.s_mount_opt;
6473 	sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6474 	sbi->s_resuid = old_opts.s_resuid;
6475 	sbi->s_resgid = old_opts.s_resgid;
6476 	sbi->s_commit_interval = old_opts.s_commit_interval;
6477 	sbi->s_min_batch_time = old_opts.s_min_batch_time;
6478 	sbi->s_max_batch_time = old_opts.s_max_batch_time;
6479 	if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6480 		ext4_release_system_zone(sb);
6481 #ifdef CONFIG_QUOTA
6482 	sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6483 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6484 		to_free[i] = get_qf_name(sb, sbi, i);
6485 		rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6486 	}
6487 	synchronize_rcu();
6488 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6489 		kfree(to_free[i]);
6490 #endif
6491 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6492 		ext4_stop_mmpd(sbi);
6493 	return err;
6494 }
6495 
6496 static int ext4_reconfigure(struct fs_context *fc)
6497 {
6498 	struct super_block *sb = fc->root->d_sb;
6499 	int ret;
6500 
6501 	fc->s_fs_info = EXT4_SB(sb);
6502 
6503 	ret = ext4_check_opt_consistency(fc, sb);
6504 	if (ret < 0)
6505 		return ret;
6506 
6507 	ret = __ext4_remount(fc, sb);
6508 	if (ret < 0)
6509 		return ret;
6510 
6511 	ext4_msg(sb, KERN_INFO, "re-mounted. Quota mode: %s.",
6512 		 ext4_quota_mode(sb));
6513 
6514 	return 0;
6515 }
6516 
6517 #ifdef CONFIG_QUOTA
6518 static int ext4_statfs_project(struct super_block *sb,
6519 			       kprojid_t projid, struct kstatfs *buf)
6520 {
6521 	struct kqid qid;
6522 	struct dquot *dquot;
6523 	u64 limit;
6524 	u64 curblock;
6525 
6526 	qid = make_kqid_projid(projid);
6527 	dquot = dqget(sb, qid);
6528 	if (IS_ERR(dquot))
6529 		return PTR_ERR(dquot);
6530 	spin_lock(&dquot->dq_dqb_lock);
6531 
6532 	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6533 			     dquot->dq_dqb.dqb_bhardlimit);
6534 	limit >>= sb->s_blocksize_bits;
6535 
6536 	if (limit && buf->f_blocks > limit) {
6537 		curblock = (dquot->dq_dqb.dqb_curspace +
6538 			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6539 		buf->f_blocks = limit;
6540 		buf->f_bfree = buf->f_bavail =
6541 			(buf->f_blocks > curblock) ?
6542 			 (buf->f_blocks - curblock) : 0;
6543 	}
6544 
6545 	limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6546 			     dquot->dq_dqb.dqb_ihardlimit);
6547 	if (limit && buf->f_files > limit) {
6548 		buf->f_files = limit;
6549 		buf->f_ffree =
6550 			(buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6551 			 (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6552 	}
6553 
6554 	spin_unlock(&dquot->dq_dqb_lock);
6555 	dqput(dquot);
6556 	return 0;
6557 }
6558 #endif
6559 
6560 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6561 {
6562 	struct super_block *sb = dentry->d_sb;
6563 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6564 	struct ext4_super_block *es = sbi->s_es;
6565 	ext4_fsblk_t overhead = 0, resv_blocks;
6566 	s64 bfree;
6567 	resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6568 
6569 	if (!test_opt(sb, MINIX_DF))
6570 		overhead = sbi->s_overhead;
6571 
6572 	buf->f_type = EXT4_SUPER_MAGIC;
6573 	buf->f_bsize = sb->s_blocksize;
6574 	buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6575 	bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6576 		percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6577 	/* prevent underflow in case that few free space is available */
6578 	buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6579 	buf->f_bavail = buf->f_bfree -
6580 			(ext4_r_blocks_count(es) + resv_blocks);
6581 	if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6582 		buf->f_bavail = 0;
6583 	buf->f_files = le32_to_cpu(es->s_inodes_count);
6584 	buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6585 	buf->f_namelen = EXT4_NAME_LEN;
6586 	buf->f_fsid = uuid_to_fsid(es->s_uuid);
6587 
6588 #ifdef CONFIG_QUOTA
6589 	if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6590 	    sb_has_quota_limits_enabled(sb, PRJQUOTA))
6591 		ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6592 #endif
6593 	return 0;
6594 }
6595 
6596 
6597 #ifdef CONFIG_QUOTA
6598 
6599 /*
6600  * Helper functions so that transaction is started before we acquire dqio_sem
6601  * to keep correct lock ordering of transaction > dqio_sem
6602  */
6603 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6604 {
6605 	return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6606 }
6607 
6608 static int ext4_write_dquot(struct dquot *dquot)
6609 {
6610 	int ret, err;
6611 	handle_t *handle;
6612 	struct inode *inode;
6613 
6614 	inode = dquot_to_inode(dquot);
6615 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6616 				    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6617 	if (IS_ERR(handle))
6618 		return PTR_ERR(handle);
6619 	ret = dquot_commit(dquot);
6620 	err = ext4_journal_stop(handle);
6621 	if (!ret)
6622 		ret = err;
6623 	return ret;
6624 }
6625 
6626 static int ext4_acquire_dquot(struct dquot *dquot)
6627 {
6628 	int ret, err;
6629 	handle_t *handle;
6630 
6631 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6632 				    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6633 	if (IS_ERR(handle))
6634 		return PTR_ERR(handle);
6635 	ret = dquot_acquire(dquot);
6636 	err = ext4_journal_stop(handle);
6637 	if (!ret)
6638 		ret = err;
6639 	return ret;
6640 }
6641 
6642 static int ext4_release_dquot(struct dquot *dquot)
6643 {
6644 	int ret, err;
6645 	handle_t *handle;
6646 
6647 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6648 				    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6649 	if (IS_ERR(handle)) {
6650 		/* Release dquot anyway to avoid endless cycle in dqput() */
6651 		dquot_release(dquot);
6652 		return PTR_ERR(handle);
6653 	}
6654 	ret = dquot_release(dquot);
6655 	err = ext4_journal_stop(handle);
6656 	if (!ret)
6657 		ret = err;
6658 	return ret;
6659 }
6660 
6661 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6662 {
6663 	struct super_block *sb = dquot->dq_sb;
6664 
6665 	if (ext4_is_quota_journalled(sb)) {
6666 		dquot_mark_dquot_dirty(dquot);
6667 		return ext4_write_dquot(dquot);
6668 	} else {
6669 		return dquot_mark_dquot_dirty(dquot);
6670 	}
6671 }
6672 
6673 static int ext4_write_info(struct super_block *sb, int type)
6674 {
6675 	int ret, err;
6676 	handle_t *handle;
6677 
6678 	/* Data block + inode block */
6679 	handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6680 	if (IS_ERR(handle))
6681 		return PTR_ERR(handle);
6682 	ret = dquot_commit_info(sb, type);
6683 	err = ext4_journal_stop(handle);
6684 	if (!ret)
6685 		ret = err;
6686 	return ret;
6687 }
6688 
6689 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6690 {
6691 	struct ext4_inode_info *ei = EXT4_I(inode);
6692 
6693 	/* The first argument of lockdep_set_subclass has to be
6694 	 * *exactly* the same as the argument to init_rwsem() --- in
6695 	 * this case, in init_once() --- or lockdep gets unhappy
6696 	 * because the name of the lock is set using the
6697 	 * stringification of the argument to init_rwsem().
6698 	 */
6699 	(void) ei;	/* shut up clang warning if !CONFIG_LOCKDEP */
6700 	lockdep_set_subclass(&ei->i_data_sem, subclass);
6701 }
6702 
6703 /*
6704  * Standard function to be called on quota_on
6705  */
6706 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6707 			 const struct path *path)
6708 {
6709 	int err;
6710 
6711 	if (!test_opt(sb, QUOTA))
6712 		return -EINVAL;
6713 
6714 	/* Quotafile not on the same filesystem? */
6715 	if (path->dentry->d_sb != sb)
6716 		return -EXDEV;
6717 
6718 	/* Quota already enabled for this file? */
6719 	if (IS_NOQUOTA(d_inode(path->dentry)))
6720 		return -EBUSY;
6721 
6722 	/* Journaling quota? */
6723 	if (EXT4_SB(sb)->s_qf_names[type]) {
6724 		/* Quotafile not in fs root? */
6725 		if (path->dentry->d_parent != sb->s_root)
6726 			ext4_msg(sb, KERN_WARNING,
6727 				"Quota file not on filesystem root. "
6728 				"Journaled quota will not work");
6729 		sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6730 	} else {
6731 		/*
6732 		 * Clear the flag just in case mount options changed since
6733 		 * last time.
6734 		 */
6735 		sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6736 	}
6737 
6738 	/*
6739 	 * When we journal data on quota file, we have to flush journal to see
6740 	 * all updates to the file when we bypass pagecache...
6741 	 */
6742 	if (EXT4_SB(sb)->s_journal &&
6743 	    ext4_should_journal_data(d_inode(path->dentry))) {
6744 		/*
6745 		 * We don't need to lock updates but journal_flush() could
6746 		 * otherwise be livelocked...
6747 		 */
6748 		jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6749 		err = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
6750 		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6751 		if (err)
6752 			return err;
6753 	}
6754 
6755 	lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6756 	err = dquot_quota_on(sb, type, format_id, path);
6757 	if (!err) {
6758 		struct inode *inode = d_inode(path->dentry);
6759 		handle_t *handle;
6760 
6761 		/*
6762 		 * Set inode flags to prevent userspace from messing with quota
6763 		 * files. If this fails, we return success anyway since quotas
6764 		 * are already enabled and this is not a hard failure.
6765 		 */
6766 		inode_lock(inode);
6767 		handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6768 		if (IS_ERR(handle))
6769 			goto unlock_inode;
6770 		EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6771 		inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6772 				S_NOATIME | S_IMMUTABLE);
6773 		err = ext4_mark_inode_dirty(handle, inode);
6774 		ext4_journal_stop(handle);
6775 	unlock_inode:
6776 		inode_unlock(inode);
6777 		if (err)
6778 			dquot_quota_off(sb, type);
6779 	}
6780 	if (err)
6781 		lockdep_set_quota_inode(path->dentry->d_inode,
6782 					     I_DATA_SEM_NORMAL);
6783 	return err;
6784 }
6785 
6786 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6787 			     unsigned int flags)
6788 {
6789 	int err;
6790 	struct inode *qf_inode;
6791 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6792 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6793 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6794 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6795 	};
6796 
6797 	BUG_ON(!ext4_has_feature_quota(sb));
6798 
6799 	if (!qf_inums[type])
6800 		return -EPERM;
6801 
6802 	qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6803 	if (IS_ERR(qf_inode)) {
6804 		ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6805 		return PTR_ERR(qf_inode);
6806 	}
6807 
6808 	/* Don't account quota for quota files to avoid recursion */
6809 	qf_inode->i_flags |= S_NOQUOTA;
6810 	lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6811 	err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6812 	if (err)
6813 		lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6814 	iput(qf_inode);
6815 
6816 	return err;
6817 }
6818 
6819 /* Enable usage tracking for all quota types. */
6820 int ext4_enable_quotas(struct super_block *sb)
6821 {
6822 	int type, err = 0;
6823 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6824 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6825 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6826 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6827 	};
6828 	bool quota_mopt[EXT4_MAXQUOTAS] = {
6829 		test_opt(sb, USRQUOTA),
6830 		test_opt(sb, GRPQUOTA),
6831 		test_opt(sb, PRJQUOTA),
6832 	};
6833 
6834 	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6835 	for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6836 		if (qf_inums[type]) {
6837 			err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6838 				DQUOT_USAGE_ENABLED |
6839 				(quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6840 			if (err) {
6841 				ext4_warning(sb,
6842 					"Failed to enable quota tracking "
6843 					"(type=%d, err=%d). Please run "
6844 					"e2fsck to fix.", type, err);
6845 				for (type--; type >= 0; type--) {
6846 					struct inode *inode;
6847 
6848 					inode = sb_dqopt(sb)->files[type];
6849 					if (inode)
6850 						inode = igrab(inode);
6851 					dquot_quota_off(sb, type);
6852 					if (inode) {
6853 						lockdep_set_quota_inode(inode,
6854 							I_DATA_SEM_NORMAL);
6855 						iput(inode);
6856 					}
6857 				}
6858 
6859 				return err;
6860 			}
6861 		}
6862 	}
6863 	return 0;
6864 }
6865 
6866 static int ext4_quota_off(struct super_block *sb, int type)
6867 {
6868 	struct inode *inode = sb_dqopt(sb)->files[type];
6869 	handle_t *handle;
6870 	int err;
6871 
6872 	/* Force all delayed allocation blocks to be allocated.
6873 	 * Caller already holds s_umount sem */
6874 	if (test_opt(sb, DELALLOC))
6875 		sync_filesystem(sb);
6876 
6877 	if (!inode || !igrab(inode))
6878 		goto out;
6879 
6880 	err = dquot_quota_off(sb, type);
6881 	if (err || ext4_has_feature_quota(sb))
6882 		goto out_put;
6883 
6884 	inode_lock(inode);
6885 	/*
6886 	 * Update modification times of quota files when userspace can
6887 	 * start looking at them. If we fail, we return success anyway since
6888 	 * this is not a hard failure and quotas are already disabled.
6889 	 */
6890 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6891 	if (IS_ERR(handle)) {
6892 		err = PTR_ERR(handle);
6893 		goto out_unlock;
6894 	}
6895 	EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6896 	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6897 	inode->i_mtime = inode->i_ctime = current_time(inode);
6898 	err = ext4_mark_inode_dirty(handle, inode);
6899 	ext4_journal_stop(handle);
6900 out_unlock:
6901 	inode_unlock(inode);
6902 out_put:
6903 	lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6904 	iput(inode);
6905 	return err;
6906 out:
6907 	return dquot_quota_off(sb, type);
6908 }
6909 
6910 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6911  * acquiring the locks... As quota files are never truncated and quota code
6912  * itself serializes the operations (and no one else should touch the files)
6913  * we don't have to be afraid of races */
6914 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6915 			       size_t len, loff_t off)
6916 {
6917 	struct inode *inode = sb_dqopt(sb)->files[type];
6918 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6919 	int offset = off & (sb->s_blocksize - 1);
6920 	int tocopy;
6921 	size_t toread;
6922 	struct buffer_head *bh;
6923 	loff_t i_size = i_size_read(inode);
6924 
6925 	if (off > i_size)
6926 		return 0;
6927 	if (off+len > i_size)
6928 		len = i_size-off;
6929 	toread = len;
6930 	while (toread > 0) {
6931 		tocopy = sb->s_blocksize - offset < toread ?
6932 				sb->s_blocksize - offset : toread;
6933 		bh = ext4_bread(NULL, inode, blk, 0);
6934 		if (IS_ERR(bh))
6935 			return PTR_ERR(bh);
6936 		if (!bh)	/* A hole? */
6937 			memset(data, 0, tocopy);
6938 		else
6939 			memcpy(data, bh->b_data+offset, tocopy);
6940 		brelse(bh);
6941 		offset = 0;
6942 		toread -= tocopy;
6943 		data += tocopy;
6944 		blk++;
6945 	}
6946 	return len;
6947 }
6948 
6949 /* Write to quotafile (we know the transaction is already started and has
6950  * enough credits) */
6951 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6952 				const char *data, size_t len, loff_t off)
6953 {
6954 	struct inode *inode = sb_dqopt(sb)->files[type];
6955 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6956 	int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6957 	int retries = 0;
6958 	struct buffer_head *bh;
6959 	handle_t *handle = journal_current_handle();
6960 
6961 	if (!handle) {
6962 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6963 			" cancelled because transaction is not started",
6964 			(unsigned long long)off, (unsigned long long)len);
6965 		return -EIO;
6966 	}
6967 	/*
6968 	 * Since we account only one data block in transaction credits,
6969 	 * then it is impossible to cross a block boundary.
6970 	 */
6971 	if (sb->s_blocksize - offset < len) {
6972 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6973 			" cancelled because not block aligned",
6974 			(unsigned long long)off, (unsigned long long)len);
6975 		return -EIO;
6976 	}
6977 
6978 	do {
6979 		bh = ext4_bread(handle, inode, blk,
6980 				EXT4_GET_BLOCKS_CREATE |
6981 				EXT4_GET_BLOCKS_METADATA_NOFAIL);
6982 	} while (PTR_ERR(bh) == -ENOSPC &&
6983 		 ext4_should_retry_alloc(inode->i_sb, &retries));
6984 	if (IS_ERR(bh))
6985 		return PTR_ERR(bh);
6986 	if (!bh)
6987 		goto out;
6988 	BUFFER_TRACE(bh, "get write access");
6989 	err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
6990 	if (err) {
6991 		brelse(bh);
6992 		return err;
6993 	}
6994 	lock_buffer(bh);
6995 	memcpy(bh->b_data+offset, data, len);
6996 	flush_dcache_page(bh->b_page);
6997 	unlock_buffer(bh);
6998 	err = ext4_handle_dirty_metadata(handle, NULL, bh);
6999 	brelse(bh);
7000 out:
7001 	if (inode->i_size < off + len) {
7002 		i_size_write(inode, off + len);
7003 		EXT4_I(inode)->i_disksize = inode->i_size;
7004 		err2 = ext4_mark_inode_dirty(handle, inode);
7005 		if (unlikely(err2 && !err))
7006 			err = err2;
7007 	}
7008 	return err ? err : len;
7009 }
7010 #endif
7011 
7012 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7013 static inline void register_as_ext2(void)
7014 {
7015 	int err = register_filesystem(&ext2_fs_type);
7016 	if (err)
7017 		printk(KERN_WARNING
7018 		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7019 }
7020 
7021 static inline void unregister_as_ext2(void)
7022 {
7023 	unregister_filesystem(&ext2_fs_type);
7024 }
7025 
7026 static inline int ext2_feature_set_ok(struct super_block *sb)
7027 {
7028 	if (ext4_has_unknown_ext2_incompat_features(sb))
7029 		return 0;
7030 	if (sb_rdonly(sb))
7031 		return 1;
7032 	if (ext4_has_unknown_ext2_ro_compat_features(sb))
7033 		return 0;
7034 	return 1;
7035 }
7036 #else
7037 static inline void register_as_ext2(void) { }
7038 static inline void unregister_as_ext2(void) { }
7039 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7040 #endif
7041 
7042 static inline void register_as_ext3(void)
7043 {
7044 	int err = register_filesystem(&ext3_fs_type);
7045 	if (err)
7046 		printk(KERN_WARNING
7047 		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7048 }
7049 
7050 static inline void unregister_as_ext3(void)
7051 {
7052 	unregister_filesystem(&ext3_fs_type);
7053 }
7054 
7055 static inline int ext3_feature_set_ok(struct super_block *sb)
7056 {
7057 	if (ext4_has_unknown_ext3_incompat_features(sb))
7058 		return 0;
7059 	if (!ext4_has_feature_journal(sb))
7060 		return 0;
7061 	if (sb_rdonly(sb))
7062 		return 1;
7063 	if (ext4_has_unknown_ext3_ro_compat_features(sb))
7064 		return 0;
7065 	return 1;
7066 }
7067 
7068 static struct file_system_type ext4_fs_type = {
7069 	.owner			= THIS_MODULE,
7070 	.name			= "ext4",
7071 	.init_fs_context	= ext4_init_fs_context,
7072 	.parameters		= ext4_param_specs,
7073 	.kill_sb		= kill_block_super,
7074 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7075 };
7076 MODULE_ALIAS_FS("ext4");
7077 
7078 /* Shared across all ext4 file systems */
7079 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7080 
7081 static int __init ext4_init_fs(void)
7082 {
7083 	int i, err;
7084 
7085 	ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7086 	ext4_li_info = NULL;
7087 
7088 	/* Build-time check for flags consistency */
7089 	ext4_check_flag_values();
7090 
7091 	for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7092 		init_waitqueue_head(&ext4__ioend_wq[i]);
7093 
7094 	err = ext4_init_es();
7095 	if (err)
7096 		return err;
7097 
7098 	err = ext4_init_pending();
7099 	if (err)
7100 		goto out7;
7101 
7102 	err = ext4_init_post_read_processing();
7103 	if (err)
7104 		goto out6;
7105 
7106 	err = ext4_init_pageio();
7107 	if (err)
7108 		goto out5;
7109 
7110 	err = ext4_init_system_zone();
7111 	if (err)
7112 		goto out4;
7113 
7114 	err = ext4_init_sysfs();
7115 	if (err)
7116 		goto out3;
7117 
7118 	err = ext4_init_mballoc();
7119 	if (err)
7120 		goto out2;
7121 	err = init_inodecache();
7122 	if (err)
7123 		goto out1;
7124 
7125 	err = ext4_fc_init_dentry_cache();
7126 	if (err)
7127 		goto out05;
7128 
7129 	register_as_ext3();
7130 	register_as_ext2();
7131 	err = register_filesystem(&ext4_fs_type);
7132 	if (err)
7133 		goto out;
7134 
7135 	return 0;
7136 out:
7137 	unregister_as_ext2();
7138 	unregister_as_ext3();
7139 	ext4_fc_destroy_dentry_cache();
7140 out05:
7141 	destroy_inodecache();
7142 out1:
7143 	ext4_exit_mballoc();
7144 out2:
7145 	ext4_exit_sysfs();
7146 out3:
7147 	ext4_exit_system_zone();
7148 out4:
7149 	ext4_exit_pageio();
7150 out5:
7151 	ext4_exit_post_read_processing();
7152 out6:
7153 	ext4_exit_pending();
7154 out7:
7155 	ext4_exit_es();
7156 
7157 	return err;
7158 }
7159 
7160 static void __exit ext4_exit_fs(void)
7161 {
7162 	ext4_destroy_lazyinit_thread();
7163 	unregister_as_ext2();
7164 	unregister_as_ext3();
7165 	unregister_filesystem(&ext4_fs_type);
7166 	ext4_fc_destroy_dentry_cache();
7167 	destroy_inodecache();
7168 	ext4_exit_mballoc();
7169 	ext4_exit_sysfs();
7170 	ext4_exit_system_zone();
7171 	ext4_exit_pageio();
7172 	ext4_exit_post_read_processing();
7173 	ext4_exit_es();
7174 	ext4_exit_pending();
7175 }
7176 
7177 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7178 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7179 MODULE_LICENSE("GPL");
7180 MODULE_SOFTDEP("pre: crc32c");
7181 module_init(ext4_init_fs)
7182 module_exit(ext4_exit_fs)
7183